Coverage Report

Created: 2026-04-18 18:15

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/home/liu/actions-runner/_work/ccv/ccv/lib/3rdparty/sqlite3/sqlite3.h
Line
Count
Source
1
/*
2
** 2001-09-15
3
**
4
** The author disclaims copyright to this source code.  In place of
5
** a legal notice, here is a blessing:
6
**
7
**    May you do good and not evil.
8
**    May you find forgiveness for yourself and forgive others.
9
**    May you share freely, never taking more than you give.
10
**
11
*************************************************************************
12
** This header file defines the interface that the SQLite library
13
** presents to client programs.  If a C-function, structure, datatype,
14
** or constant definition does not appear in this file, then it is
15
** not a published API of SQLite, is subject to change without
16
** notice, and should not be referenced by programs that use SQLite.
17
**
18
** Some of the definitions that are in this file are marked as
19
** "experimental".  Experimental interfaces are normally new
20
** features recently added to SQLite.  We do not anticipate changes
21
** to experimental interfaces but reserve the right to make minor changes
22
** if experience from use "in the wild" suggest such changes are prudent.
23
**
24
** The official C-language API documentation for SQLite is derived
25
** from comments in this file.  This file is the authoritative source
26
** on how SQLite interfaces are supposed to operate.
27
**
28
** The name of this file under configuration management is "sqlite.h.in".
29
** The makefile makes some minor changes to this file (such as inserting
30
** the version number) and changes its name to "sqlite3.h" as
31
** part of the build process.
32
*/
33
#ifndef SQLITE3_H
34
#define SQLITE3_H
35
#include <stdarg.h>     /* Needed for the definition of va_list */
36
37
/*
38
** Make sure we can call this stuff from C++.
39
*/
40
#ifdef __cplusplus
41
extern "C" {
42
#endif
43
44
45
/*
46
** Facilitate override of interface linkage and calling conventions.
47
** Be aware that these macros may not be used within this particular
48
** translation of the amalgamation and its associated header file.
49
**
50
** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the
51
** compiler that the target identifier should have external linkage.
52
**
53
** The SQLITE_CDECL macro is used to set the calling convention for
54
** public functions that accept a variable number of arguments.
55
**
56
** The SQLITE_APICALL macro is used to set the calling convention for
57
** public functions that accept a fixed number of arguments.
58
**
59
** The SQLITE_STDCALL macro is no longer used and is now deprecated.
60
**
61
** The SQLITE_CALLBACK macro is used to set the calling convention for
62
** function pointers.
63
**
64
** The SQLITE_SYSAPI macro is used to set the calling convention for
65
** functions provided by the operating system.
66
**
67
** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and
68
** SQLITE_SYSAPI macros are used only when building for environments
69
** that require non-default calling conventions.
70
*/
71
#ifndef SQLITE_EXTERN
72
# define SQLITE_EXTERN extern
73
#endif
74
#ifndef SQLITE_API
75
# define SQLITE_API
76
#endif
77
#ifndef SQLITE_CDECL
78
# define SQLITE_CDECL
79
#endif
80
#ifndef SQLITE_APICALL
81
# define SQLITE_APICALL
82
#endif
83
#ifndef SQLITE_STDCALL
84
# define SQLITE_STDCALL SQLITE_APICALL
85
#endif
86
#ifndef SQLITE_CALLBACK
87
# define SQLITE_CALLBACK
88
#endif
89
#ifndef SQLITE_SYSAPI
90
# define SQLITE_SYSAPI
91
#endif
92
93
/*
94
** These no-op macros are used in front of interfaces to mark those
95
** interfaces as either deprecated or experimental.  New applications
96
** should not use deprecated interfaces - they are supported for backwards
97
** compatibility only.  Application writers should be aware that
98
** experimental interfaces are subject to change in point releases.
99
**
100
** These macros used to resolve to various kinds of compiler magic that
101
** would generate warning messages when they were used.  But that
102
** compiler magic ended up generating such a flurry of bug reports
103
** that we have taken it all out and gone back to using simple
104
** noop macros.
105
*/
106
#define SQLITE_DEPRECATED
107
#define SQLITE_EXPERIMENTAL
108
109
/*
110
** Ensure these symbols were not defined by some previous header file.
111
*/
112
#ifdef SQLITE_VERSION
113
# undef SQLITE_VERSION
114
#endif
115
#ifdef SQLITE_VERSION_NUMBER
116
# undef SQLITE_VERSION_NUMBER
117
#endif
118
119
/*
120
** CAPI3REF: Compile-Time Library Version Numbers
121
**
122
** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
123
** evaluates to a string literal that is the SQLite version in the
124
** format "X.Y.Z" where X is the major version number (always 3 for
125
** SQLite3) and Y is the minor version number and Z is the release number.)^
126
** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
127
** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
128
** numbers used in [SQLITE_VERSION].)^
129
** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
130
** be larger than the release from which it is derived.  Either Y will
131
** be held constant and Z will be incremented or else Y will be incremented
132
** and Z will be reset to zero.
133
**
134
** Since [version 3.6.18] ([dateof:3.6.18]),
135
** SQLite source code has been stored in the
136
** <a href="http://fossil-scm.org/">Fossil configuration management
137
** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
138
** a string which identifies a particular check-in of SQLite
139
** within its configuration management system.  ^The SQLITE_SOURCE_ID
140
** string contains the date and time of the check-in (UTC) and a SHA1
141
** or SHA3-256 hash of the entire source tree.  If the source code has
142
** been edited in any way since it was last checked in, then the last
143
** four hexadecimal digits of the hash may be modified.
144
**
145
** See also: [sqlite3_libversion()],
146
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
147
** [sqlite_version()] and [sqlite_source_id()].
148
*/
149
#define SQLITE_VERSION        "3.50.3"
150
#define SQLITE_VERSION_NUMBER 3050003
151
#define SQLITE_SOURCE_ID      "2025-07-17 13:25:10 3ce993b8657d6d9deda380a93cdd6404a8c8ba1b185b2bc423703e41ae5f2543"
152
153
/*
154
** CAPI3REF: Run-Time Library Version Numbers
155
** KEYWORDS: sqlite3_version sqlite3_sourceid
156
**
157
** These interfaces provide the same information as the [SQLITE_VERSION],
158
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
159
** but are associated with the library instead of the header file.  ^(Cautious
160
** programmers might include assert() statements in their application to
161
** verify that values returned by these interfaces match the macros in
162
** the header, and thus ensure that the application is
163
** compiled with matching library and header files.
164
**
165
** <blockquote><pre>
166
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
167
** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
168
** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
169
** </pre></blockquote>)^
170
**
171
** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
172
** macro.  ^The sqlite3_libversion() function returns a pointer to the
173
** to the sqlite3_version[] string constant.  The sqlite3_libversion()
174
** function is provided for use in DLLs since DLL users usually do not have
175
** direct access to string constants within the DLL.  ^The
176
** sqlite3_libversion_number() function returns an integer equal to
177
** [SQLITE_VERSION_NUMBER].  ^(The sqlite3_sourceid() function returns
178
** a pointer to a string constant whose value is the same as the
179
** [SQLITE_SOURCE_ID] C preprocessor macro.  Except if SQLite is built
180
** using an edited copy of [the amalgamation], then the last four characters
181
** of the hash might be different from [SQLITE_SOURCE_ID].)^
182
**
183
** See also: [sqlite_version()] and [sqlite_source_id()].
184
*/
185
SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
186
SQLITE_API const char *sqlite3_libversion(void);
187
SQLITE_API const char *sqlite3_sourceid(void);
188
SQLITE_API int sqlite3_libversion_number(void);
189
190
/*
191
** CAPI3REF: Run-Time Library Compilation Options Diagnostics
192
**
193
** ^The sqlite3_compileoption_used() function returns 0 or 1
194
** indicating whether the specified option was defined at
195
** compile time.  ^The SQLITE_ prefix may be omitted from the
196
** option name passed to sqlite3_compileoption_used().
197
**
198
** ^The sqlite3_compileoption_get() function allows iterating
199
** over the list of options that were defined at compile time by
200
** returning the N-th compile time option string.  ^If N is out of range,
201
** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_
202
** prefix is omitted from any strings returned by
203
** sqlite3_compileoption_get().
204
**
205
** ^Support for the diagnostic functions sqlite3_compileoption_used()
206
** and sqlite3_compileoption_get() may be omitted by specifying the
207
** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
208
**
209
** See also: SQL functions [sqlite_compileoption_used()] and
210
** [sqlite_compileoption_get()] and the [compile_options pragma].
211
*/
212
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
213
SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
214
SQLITE_API const char *sqlite3_compileoption_get(int N);
215
#else
216
# define sqlite3_compileoption_used(X) 0
217
# define sqlite3_compileoption_get(X)  ((void*)0)
218
#endif
219
220
/*
221
** CAPI3REF: Test To See If The Library Is Threadsafe
222
**
223
** ^The sqlite3_threadsafe() function returns zero if and only if
224
** SQLite was compiled with mutexing code omitted due to the
225
** [SQLITE_THREADSAFE] compile-time option being set to 0.
226
**
227
** SQLite can be compiled with or without mutexes.  When
228
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
229
** are enabled and SQLite is threadsafe.  When the
230
** [SQLITE_THREADSAFE] macro is 0,
231
** the mutexes are omitted.  Without the mutexes, it is not safe
232
** to use SQLite concurrently from more than one thread.
233
**
234
** Enabling mutexes incurs a measurable performance penalty.
235
** So if speed is of utmost importance, it makes sense to disable
236
** the mutexes.  But for maximum safety, mutexes should be enabled.
237
** ^The default behavior is for mutexes to be enabled.
238
**
239
** This interface can be used by an application to make sure that the
240
** version of SQLite that it is linking against was compiled with
241
** the desired setting of the [SQLITE_THREADSAFE] macro.
242
**
243
** This interface only reports on the compile-time mutex setting
244
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
245
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
246
** can be fully or partially disabled using a call to [sqlite3_config()]
247
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
248
** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
249
** sqlite3_threadsafe() function shows only the compile-time setting of
250
** thread safety, not any run-time changes to that setting made by
251
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
252
** is unchanged by calls to sqlite3_config().)^
253
**
254
** See the [threading mode] documentation for additional information.
255
*/
256
SQLITE_API int sqlite3_threadsafe(void);
257
258
/*
259
** CAPI3REF: Database Connection Handle
260
** KEYWORDS: {database connection} {database connections}
261
**
262
** Each open SQLite database is represented by a pointer to an instance of
263
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
264
** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
265
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
266
** and [sqlite3_close_v2()] are its destructors.  There are many other
267
** interfaces (such as
268
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
269
** [sqlite3_busy_timeout()] to name but three) that are methods on an
270
** sqlite3 object.
271
*/
272
typedef struct sqlite3 sqlite3;
273
274
/*
275
** CAPI3REF: 64-Bit Integer Types
276
** KEYWORDS: sqlite_int64 sqlite_uint64
277
**
278
** Because there is no cross-platform way to specify 64-bit integer types
279
** SQLite includes typedefs for 64-bit signed and unsigned integers.
280
**
281
** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
282
** The sqlite_int64 and sqlite_uint64 types are supported for backwards
283
** compatibility only.
284
**
285
** ^The sqlite3_int64 and sqlite_int64 types can store integer values
286
** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
287
** sqlite3_uint64 and sqlite_uint64 types can store integer values
288
** between 0 and +18446744073709551615 inclusive.
289
*/
290
#ifdef SQLITE_INT64_TYPE
291
  typedef SQLITE_INT64_TYPE sqlite_int64;
292
# ifdef SQLITE_UINT64_TYPE
293
    typedef SQLITE_UINT64_TYPE sqlite_uint64;
294
# else
295
    typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
296
# endif
297
#elif defined(_MSC_VER) || defined(__BORLANDC__)
298
  typedef __int64 sqlite_int64;
299
  typedef unsigned __int64 sqlite_uint64;
300
#else
301
  typedef long long int sqlite_int64;
302
  typedef unsigned long long int sqlite_uint64;
303
#endif
304
typedef sqlite_int64 sqlite3_int64;
305
typedef sqlite_uint64 sqlite3_uint64;
306
307
/*
308
** If compiling for a processor that lacks floating point support,
309
** substitute integer for floating-point.
310
*/
311
#ifdef SQLITE_OMIT_FLOATING_POINT
312
# define double sqlite3_int64
313
#endif
314
315
/*
316
** CAPI3REF: Closing A Database Connection
317
** DESTRUCTOR: sqlite3
318
**
319
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
320
** for the [sqlite3] object.
321
** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
322
** the [sqlite3] object is successfully destroyed and all associated
323
** resources are deallocated.
324
**
325
** Ideally, applications should [sqlite3_finalize | finalize] all
326
** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
327
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
328
** with the [sqlite3] object prior to attempting to close the object.
329
** ^If the database connection is associated with unfinalized prepared
330
** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
331
** sqlite3_close() will leave the database connection open and return
332
** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
333
** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
334
** it returns [SQLITE_OK] regardless, but instead of deallocating the database
335
** connection immediately, it marks the database connection as an unusable
336
** "zombie" and makes arrangements to automatically deallocate the database
337
** connection after all prepared statements are finalized, all BLOB handles
338
** are closed, and all backups have finished. The sqlite3_close_v2() interface
339
** is intended for use with host languages that are garbage collected, and
340
** where the order in which destructors are called is arbitrary.
341
**
342
** ^If an [sqlite3] object is destroyed while a transaction is open,
343
** the transaction is automatically rolled back.
344
**
345
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
346
** must be either a NULL
347
** pointer or an [sqlite3] object pointer obtained
348
** from [sqlite3_open()], [sqlite3_open16()], or
349
** [sqlite3_open_v2()], and not previously closed.
350
** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
351
** argument is a harmless no-op.
352
*/
353
SQLITE_API int sqlite3_close(sqlite3*);
354
SQLITE_API int sqlite3_close_v2(sqlite3*);
355
356
/*
357
** The type for a callback function.
358
** This is legacy and deprecated.  It is included for historical
359
** compatibility and is not documented.
360
*/
361
typedef int (*sqlite3_callback)(void*,int,char**, char**);
362
363
/*
364
** CAPI3REF: One-Step Query Execution Interface
365
** METHOD: sqlite3
366
**
367
** The sqlite3_exec() interface is a convenience wrapper around
368
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
369
** that allows an application to run multiple statements of SQL
370
** without having to use a lot of C code.
371
**
372
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
373
** semicolon-separate SQL statements passed into its 2nd argument,
374
** in the context of the [database connection] passed in as its 1st
375
** argument.  ^If the callback function of the 3rd argument to
376
** sqlite3_exec() is not NULL, then it is invoked for each result row
377
** coming out of the evaluated SQL statements.  ^The 4th argument to
378
** sqlite3_exec() is relayed through to the 1st argument of each
379
** callback invocation.  ^If the callback pointer to sqlite3_exec()
380
** is NULL, then no callback is ever invoked and result rows are
381
** ignored.
382
**
383
** ^If an error occurs while evaluating the SQL statements passed into
384
** sqlite3_exec(), then execution of the current statement stops and
385
** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
386
** is not NULL then any error message is written into memory obtained
387
** from [sqlite3_malloc()] and passed back through the 5th parameter.
388
** To avoid memory leaks, the application should invoke [sqlite3_free()]
389
** on error message strings returned through the 5th parameter of
390
** sqlite3_exec() after the error message string is no longer needed.
391
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
392
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
393
** NULL before returning.
394
**
395
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
396
** routine returns SQLITE_ABORT without invoking the callback again and
397
** without running any subsequent SQL statements.
398
**
399
** ^The 2nd argument to the sqlite3_exec() callback function is the
400
** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
401
** callback is an array of pointers to strings obtained as if from
402
** [sqlite3_column_text()], one for each column.  ^If an element of a
403
** result row is NULL then the corresponding string pointer for the
404
** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
405
** sqlite3_exec() callback is an array of pointers to strings where each
406
** entry represents the name of corresponding result column as obtained
407
** from [sqlite3_column_name()].
408
**
409
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
410
** to an empty string, or a pointer that contains only whitespace and/or
411
** SQL comments, then no SQL statements are evaluated and the database
412
** is not changed.
413
**
414
** Restrictions:
415
**
416
** <ul>
417
** <li> The application must ensure that the 1st parameter to sqlite3_exec()
418
**      is a valid and open [database connection].
419
** <li> The application must not close the [database connection] specified by
420
**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
421
** <li> The application must not modify the SQL statement text passed into
422
**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
423
** <li> The application must not dereference the arrays or string pointers
424
**       passed as the 3rd and 4th callback parameters after it returns.
425
** </ul>
426
*/
427
SQLITE_API int sqlite3_exec(
428
  sqlite3*,                                  /* An open database */
429
  const char *sql,                           /* SQL to be evaluated */
430
  int (*callback)(void*,int,char**,char**),  /* Callback function */
431
  void *,                                    /* 1st argument to callback */
432
  char **errmsg                              /* Error msg written here */
433
);
434
435
/*
436
** CAPI3REF: Result Codes
437
** KEYWORDS: {result code definitions}
438
**
439
** Many SQLite functions return an integer result code from the set shown
440
** here in order to indicate success or failure.
441
**
442
** New error codes may be added in future versions of SQLite.
443
**
444
** See also: [extended result code definitions]
445
*/
446
50
#define SQLITE_OK           0   /* Successful result */
447
/* beginning-of-error-codes */
448
#define SQLITE_ERROR        1   /* Generic error */
449
#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
450
#define SQLITE_PERM         3   /* Access permission denied */
451
#define SQLITE_ABORT        4   /* Callback routine requested an abort */
452
#define SQLITE_BUSY         5   /* The database file is locked */
453
#define SQLITE_LOCKED       6   /* A table in the database is locked */
454
#define SQLITE_NOMEM        7   /* A malloc() failed */
455
#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
456
#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
457
#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
458
#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
459
#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
460
#define SQLITE_FULL        13   /* Insertion failed because database is full */
461
#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
462
#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
463
#define SQLITE_EMPTY       16   /* Internal use only */
464
#define SQLITE_SCHEMA      17   /* The database schema changed */
465
#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
466
#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
467
#define SQLITE_MISMATCH    20   /* Data type mismatch */
468
#define SQLITE_MISUSE      21   /* Library used incorrectly */
469
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
470
#define SQLITE_AUTH        23   /* Authorization denied */
471
#define SQLITE_FORMAT      24   /* Not used */
472
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
473
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
474
#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
475
#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
476
134
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
477
30
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
478
/* end-of-error-codes */
479
480
/*
481
** CAPI3REF: Extended Result Codes
482
** KEYWORDS: {extended result code definitions}
483
**
484
** In its default configuration, SQLite API routines return one of 30 integer
485
** [result codes].  However, experience has shown that many of
486
** these result codes are too coarse-grained.  They do not provide as
487
** much information about problems as programmers might like.  In an effort to
488
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
489
** and later) include
490
** support for additional result codes that provide more detailed information
491
** about errors. These [extended result codes] are enabled or disabled
492
** on a per database connection basis using the
493
** [sqlite3_extended_result_codes()] API.  Or, the extended code for
494
** the most recent error can be obtained using
495
** [sqlite3_extended_errcode()].
496
*/
497
#define SQLITE_ERROR_MISSING_COLLSEQ   (SQLITE_ERROR | (1<<8))
498
#define SQLITE_ERROR_RETRY             (SQLITE_ERROR | (2<<8))
499
#define SQLITE_ERROR_SNAPSHOT          (SQLITE_ERROR | (3<<8))
500
#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
501
#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
502
#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
503
#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
504
#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
505
#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
506
#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
507
#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
508
#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
509
#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
510
#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
511
#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
512
#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
513
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
514
#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
515
#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
516
#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
517
#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
518
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
519
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
520
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
521
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
522
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
523
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
524
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
525
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
526
#define SQLITE_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
527
#define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<8))
528
#define SQLITE_IOERR_BEGIN_ATOMIC      (SQLITE_IOERR | (29<<8))
529
#define SQLITE_IOERR_COMMIT_ATOMIC     (SQLITE_IOERR | (30<<8))
530
#define SQLITE_IOERR_ROLLBACK_ATOMIC   (SQLITE_IOERR | (31<<8))
531
#define SQLITE_IOERR_DATA              (SQLITE_IOERR | (32<<8))
532
#define SQLITE_IOERR_CORRUPTFS         (SQLITE_IOERR | (33<<8))
533
#define SQLITE_IOERR_IN_PAGE           (SQLITE_IOERR | (34<<8))
534
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
535
#define SQLITE_LOCKED_VTAB             (SQLITE_LOCKED |  (2<<8))
536
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
537
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
538
#define SQLITE_BUSY_TIMEOUT            (SQLITE_BUSY   |  (3<<8))
539
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
540
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
541
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
542
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
543
#define SQLITE_CANTOPEN_DIRTYWAL       (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
544
#define SQLITE_CANTOPEN_SYMLINK        (SQLITE_CANTOPEN | (6<<8))
545
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
546
#define SQLITE_CORRUPT_SEQUENCE        (SQLITE_CORRUPT | (2<<8))
547
#define SQLITE_CORRUPT_INDEX           (SQLITE_CORRUPT | (3<<8))
548
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
549
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
550
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
551
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
552
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
553
#define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))
554
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
555
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
556
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
557
#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
558
#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
559
#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
560
#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
561
#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
562
#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
563
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
564
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
565
#define SQLITE_CONSTRAINT_PINNED       (SQLITE_CONSTRAINT |(11<<8))
566
#define SQLITE_CONSTRAINT_DATATYPE     (SQLITE_CONSTRAINT |(12<<8))
567
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
568
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
569
#define SQLITE_NOTICE_RBU              (SQLITE_NOTICE | (3<<8))
570
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
571
#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
572
#define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))
573
#define SQLITE_OK_SYMLINK              (SQLITE_OK | (2<<8)) /* internal use only */
574
575
/*
576
** CAPI3REF: Flags For File Open Operations
577
**
578
** These bit values are intended for use in the
579
** 3rd parameter to the [sqlite3_open_v2()] interface and
580
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
581
**
582
** Only those flags marked as "Ok for sqlite3_open_v2()" may be
583
** used as the third argument to the [sqlite3_open_v2()] interface.
584
** The other flags have historically been ignored by sqlite3_open_v2(),
585
** though future versions of SQLite might change so that an error is
586
** raised if any of the disallowed bits are passed into sqlite3_open_v2().
587
** Applications should not depend on the historical behavior.
588
**
589
** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into
590
** [sqlite3_open_v2()] does *not* cause the underlying database file
591
** to be opened using O_EXCL.  Passing SQLITE_OPEN_EXCLUSIVE into
592
** [sqlite3_open_v2()] has historically be a no-op and might become an
593
** error in future versions of SQLite.
594
*/
595
#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
596
#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
597
#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
598
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
599
#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
600
#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
601
#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
602
#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
603
#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
604
#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
605
#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
606
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
607
#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
608
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
609
#define SQLITE_OPEN_SUPER_JOURNAL    0x00004000  /* VFS only */
610
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
611
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
612
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
613
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
614
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
615
#define SQLITE_OPEN_NOFOLLOW         0x01000000  /* Ok for sqlite3_open_v2() */
616
#define SQLITE_OPEN_EXRESCODE        0x02000000  /* Extended result codes */
617
618
/* Reserved:                         0x00F00000 */
619
/* Legacy compatibility: */
620
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
621
622
623
/*
624
** CAPI3REF: Device Characteristics
625
**
626
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
627
** object returns an integer which is a vector of these
628
** bit values expressing I/O characteristics of the mass storage
629
** device that holds the file that the [sqlite3_io_methods]
630
** refers to.
631
**
632
** The SQLITE_IOCAP_ATOMIC property means that all writes of
633
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
634
** mean that writes of blocks that are nnn bytes in size and
635
** are aligned to an address which is an integer multiple of
636
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
637
** that when data is appended to a file, the data is appended
638
** first then the size of the file is extended, never the other
639
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
640
** information is written to disk in the same order as calls
641
** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
642
** after reboot following a crash or power loss, the only bytes in a
643
** file that were written at the application level might have changed
644
** and that adjacent bytes, even bytes within the same sector are
645
** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
646
** flag indicates that a file cannot be deleted when open.  The
647
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
648
** read-only media and cannot be changed even by processes with
649
** elevated privileges.
650
**
651
** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
652
** filesystem supports doing multiple write operations atomically when those
653
** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
654
** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
655
**
656
** The SQLITE_IOCAP_SUBPAGE_READ property means that it is ok to read
657
** from the database file in amounts that are not a multiple of the
658
** page size and that do not begin at a page boundary.  Without this
659
** property, SQLite is careful to only do full-page reads and write
660
** on aligned pages, with the one exception that it will do a sub-page
661
** read of the first page to access the database header.
662
*/
663
#define SQLITE_IOCAP_ATOMIC                 0x00000001
664
#define SQLITE_IOCAP_ATOMIC512              0x00000002
665
#define SQLITE_IOCAP_ATOMIC1K               0x00000004
666
#define SQLITE_IOCAP_ATOMIC2K               0x00000008
667
#define SQLITE_IOCAP_ATOMIC4K               0x00000010
668
#define SQLITE_IOCAP_ATOMIC8K               0x00000020
669
#define SQLITE_IOCAP_ATOMIC16K              0x00000040
670
#define SQLITE_IOCAP_ATOMIC32K              0x00000080
671
#define SQLITE_IOCAP_ATOMIC64K              0x00000100
672
#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
673
#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
674
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
675
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
676
#define SQLITE_IOCAP_IMMUTABLE              0x00002000
677
#define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000
678
#define SQLITE_IOCAP_SUBPAGE_READ           0x00008000
679
680
/*
681
** CAPI3REF: File Locking Levels
682
**
683
** SQLite uses one of these integer values as the second
684
** argument to calls it makes to the xLock() and xUnlock() methods
685
** of an [sqlite3_io_methods] object.  These values are ordered from
686
** lest restrictive to most restrictive.
687
**
688
** The argument to xLock() is always SHARED or higher.  The argument to
689
** xUnlock is either SHARED or NONE.
690
*/
691
#define SQLITE_LOCK_NONE          0       /* xUnlock() only */
692
#define SQLITE_LOCK_SHARED        1       /* xLock() or xUnlock() */
693
#define SQLITE_LOCK_RESERVED      2       /* xLock() only */
694
#define SQLITE_LOCK_PENDING       3       /* xLock() only */
695
#define SQLITE_LOCK_EXCLUSIVE     4       /* xLock() only */
696
697
/*
698
** CAPI3REF: Synchronization Type Flags
699
**
700
** When SQLite invokes the xSync() method of an
701
** [sqlite3_io_methods] object it uses a combination of
702
** these integer values as the second argument.
703
**
704
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
705
** sync operation only needs to flush data to mass storage.  Inode
706
** information need not be flushed. If the lower four bits of the flag
707
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
708
** If the lower four bits equal SQLITE_SYNC_FULL, that means
709
** to use Mac OS X style fullsync instead of fsync().
710
**
711
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
712
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
713
** settings.  The [synchronous pragma] determines when calls to the
714
** xSync VFS method occur and applies uniformly across all platforms.
715
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
716
** energetic or rigorous or forceful the sync operations are and
717
** only make a difference on Mac OSX for the default SQLite code.
718
** (Third-party VFS implementations might also make the distinction
719
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
720
** operating systems natively supported by SQLite, only Mac OSX
721
** cares about the difference.)
722
*/
723
#define SQLITE_SYNC_NORMAL        0x00002
724
#define SQLITE_SYNC_FULL          0x00003
725
#define SQLITE_SYNC_DATAONLY      0x00010
726
727
/*
728
** CAPI3REF: OS Interface Open File Handle
729
**
730
** An [sqlite3_file] object represents an open file in the
731
** [sqlite3_vfs | OS interface layer].  Individual OS interface
732
** implementations will
733
** want to subclass this object by appending additional fields
734
** for their own use.  The pMethods entry is a pointer to an
735
** [sqlite3_io_methods] object that defines methods for performing
736
** I/O operations on the open file.
737
*/
738
typedef struct sqlite3_file sqlite3_file;
739
struct sqlite3_file {
740
  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
741
};
742
743
/*
744
** CAPI3REF: OS Interface File Virtual Methods Object
745
**
746
** Every file opened by the [sqlite3_vfs.xOpen] method populates an
747
** [sqlite3_file] object (or, more commonly, a subclass of the
748
** [sqlite3_file] object) with a pointer to an instance of this object.
749
** This object defines the methods used to perform various operations
750
** against the open file represented by the [sqlite3_file] object.
751
**
752
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
753
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
754
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
755
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
756
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
757
** to NULL.
758
**
759
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
760
** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
761
** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
762
** flag may be ORed in to indicate that only the data of the file
763
** and not its inode needs to be synced.
764
**
765
** The integer values to xLock() and xUnlock() are one of
766
** <ul>
767
** <li> [SQLITE_LOCK_NONE],
768
** <li> [SQLITE_LOCK_SHARED],
769
** <li> [SQLITE_LOCK_RESERVED],
770
** <li> [SQLITE_LOCK_PENDING], or
771
** <li> [SQLITE_LOCK_EXCLUSIVE].
772
** </ul>
773
** xLock() upgrades the database file lock.  In other words, xLock() moves the
774
** database file lock in the direction NONE toward EXCLUSIVE. The argument to
775
** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never
776
** SQLITE_LOCK_NONE.  If the database file lock is already at or above the
777
** requested lock, then the call to xLock() is a no-op.
778
** xUnlock() downgrades the database file lock to either SHARED or NONE.
779
** If the lock is already at or below the requested lock state, then the call
780
** to xUnlock() is a no-op.
781
** The xCheckReservedLock() method checks whether any database connection,
782
** either in this process or in some other process, is holding a RESERVED,
783
** PENDING, or EXCLUSIVE lock on the file.  It returns, via its output
784
** pointer parameter, true if such a lock exists and false otherwise.
785
**
786
** The xFileControl() method is a generic interface that allows custom
787
** VFS implementations to directly control an open file using the
788
** [sqlite3_file_control()] interface.  The second "op" argument is an
789
** integer opcode.  The third argument is a generic pointer intended to
790
** point to a structure that may contain arguments or space in which to
791
** write return values.  Potential uses for xFileControl() might be
792
** functions to enable blocking locks with timeouts, to change the
793
** locking strategy (for example to use dot-file locks), to inquire
794
** about the status of a lock, or to break stale locks.  The SQLite
795
** core reserves all opcodes less than 100 for its own use.
796
** A [file control opcodes | list of opcodes] less than 100 is available.
797
** Applications that define a custom xFileControl method should use opcodes
798
** greater than 100 to avoid conflicts.  VFS implementations should
799
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
800
** recognize.
801
**
802
** The xSectorSize() method returns the sector size of the
803
** device that underlies the file.  The sector size is the
804
** minimum write that can be performed without disturbing
805
** other bytes in the file.  The xDeviceCharacteristics()
806
** method returns a bit vector describing behaviors of the
807
** underlying device:
808
**
809
** <ul>
810
** <li> [SQLITE_IOCAP_ATOMIC]
811
** <li> [SQLITE_IOCAP_ATOMIC512]
812
** <li> [SQLITE_IOCAP_ATOMIC1K]
813
** <li> [SQLITE_IOCAP_ATOMIC2K]
814
** <li> [SQLITE_IOCAP_ATOMIC4K]
815
** <li> [SQLITE_IOCAP_ATOMIC8K]
816
** <li> [SQLITE_IOCAP_ATOMIC16K]
817
** <li> [SQLITE_IOCAP_ATOMIC32K]
818
** <li> [SQLITE_IOCAP_ATOMIC64K]
819
** <li> [SQLITE_IOCAP_SAFE_APPEND]
820
** <li> [SQLITE_IOCAP_SEQUENTIAL]
821
** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
822
** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
823
** <li> [SQLITE_IOCAP_IMMUTABLE]
824
** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
825
** <li> [SQLITE_IOCAP_SUBPAGE_READ]
826
** </ul>
827
**
828
** The SQLITE_IOCAP_ATOMIC property means that all writes of
829
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
830
** mean that writes of blocks that are nnn bytes in size and
831
** are aligned to an address which is an integer multiple of
832
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
833
** that when data is appended to a file, the data is appended
834
** first then the size of the file is extended, never the other
835
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
836
** information is written to disk in the same order as calls
837
** to xWrite().
838
**
839
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
840
** in the unread portions of the buffer with zeros.  A VFS that
841
** fails to zero-fill short reads might seem to work.  However,
842
** failure to zero-fill short reads will eventually lead to
843
** database corruption.
844
*/
845
typedef struct sqlite3_io_methods sqlite3_io_methods;
846
struct sqlite3_io_methods {
847
  int iVersion;
848
  int (*xClose)(sqlite3_file*);
849
  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
850
  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
851
  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
852
  int (*xSync)(sqlite3_file*, int flags);
853
  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
854
  int (*xLock)(sqlite3_file*, int);
855
  int (*xUnlock)(sqlite3_file*, int);
856
  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
857
  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
858
  int (*xSectorSize)(sqlite3_file*);
859
  int (*xDeviceCharacteristics)(sqlite3_file*);
860
  /* Methods above are valid for version 1 */
861
  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
862
  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
863
  void (*xShmBarrier)(sqlite3_file*);
864
  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
865
  /* Methods above are valid for version 2 */
866
  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
867
  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
868
  /* Methods above are valid for version 3 */
869
  /* Additional methods may be added in future releases */
870
};
871
872
/*
873
** CAPI3REF: Standard File Control Opcodes
874
** KEYWORDS: {file control opcodes} {file control opcode}
875
**
876
** These integer constants are opcodes for the xFileControl method
877
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
878
** interface.
879
**
880
** <ul>
881
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
882
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
883
** opcode causes the xFileControl method to write the current state of
884
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
885
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
886
** into an integer that the pArg argument points to.
887
** This capability is only available if SQLite is compiled with [SQLITE_DEBUG].
888
**
889
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
890
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
891
** layer a hint of how large the database file will grow to be during the
892
** current transaction.  This hint is not guaranteed to be accurate but it
893
** is often close.  The underlying VFS might choose to preallocate database
894
** file space based on this hint in order to help writes to the database
895
** file run faster.
896
**
897
** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
898
** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
899
** implements [sqlite3_deserialize()] to set an upper bound on the size
900
** of the in-memory database.  The argument is a pointer to a [sqlite3_int64].
901
** If the integer pointed to is negative, then it is filled in with the
902
** current limit.  Otherwise the limit is set to the larger of the value
903
** of the integer pointed to and the current database size.  The integer
904
** pointed to is set to the new limit.
905
**
906
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
907
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
908
** extends and truncates the database file in chunks of a size specified
909
** by the user. The fourth argument to [sqlite3_file_control()] should
910
** point to an integer (type int) containing the new chunk-size to use
911
** for the nominated database. Allocating database file space in large
912
** chunks (say 1MB at a time), may reduce file-system fragmentation and
913
** improve performance on some systems.
914
**
915
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
916
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
917
** to the [sqlite3_file] object associated with a particular database
918
** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
919
**
920
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
921
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
922
** to the [sqlite3_file] object associated with the journal file (either
923
** the [rollback journal] or the [write-ahead log]) for a particular database
924
** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
925
**
926
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
927
** No longer in use.
928
**
929
** <li>[[SQLITE_FCNTL_SYNC]]
930
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
931
** sent to the VFS immediately before the xSync method is invoked on a
932
** database file descriptor. Or, if the xSync method is not invoked
933
** because the user has configured SQLite with
934
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
935
** of the xSync method. In most cases, the pointer argument passed with
936
** this file-control is NULL. However, if the database file is being synced
937
** as part of a multi-database commit, the argument points to a nul-terminated
938
** string containing the transactions super-journal file name. VFSes that
939
** do not need this signal should silently ignore this opcode. Applications
940
** should not call [sqlite3_file_control()] with this opcode as doing so may
941
** disrupt the operation of the specialized VFSes that do require it.
942
**
943
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
944
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
945
** and sent to the VFS after a transaction has been committed immediately
946
** but before the database is unlocked. VFSes that do not need this signal
947
** should silently ignore this opcode. Applications should not call
948
** [sqlite3_file_control()] with this opcode as doing so may disrupt the
949
** operation of the specialized VFSes that do require it.
950
**
951
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
952
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
953
** retry counts and intervals for certain disk I/O operations for the
954
** windows [VFS] in order to provide robustness in the presence of
955
** anti-virus programs.  By default, the windows VFS will retry file read,
956
** file write, and file delete operations up to 10 times, with a delay
957
** of 25 milliseconds before the first retry and with the delay increasing
958
** by an additional 25 milliseconds with each subsequent retry.  This
959
** opcode allows these two values (10 retries and 25 milliseconds of delay)
960
** to be adjusted.  The values are changed for all database connections
961
** within the same process.  The argument is a pointer to an array of two
962
** integers where the first integer is the new retry count and the second
963
** integer is the delay.  If either integer is negative, then the setting
964
** is not changed but instead the prior value of that setting is written
965
** into the array entry, allowing the current retry settings to be
966
** interrogated.  The zDbName parameter is ignored.
967
**
968
** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
969
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
970
** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
971
** write ahead log ([WAL file]) and shared memory
972
** files used for transaction control
973
** are automatically deleted when the latest connection to the database
974
** closes.  Setting persistent WAL mode causes those files to persist after
975
** close.  Persisting the files is useful when other processes that do not
976
** have write permission on the directory containing the database file want
977
** to read the database file, as the WAL and shared memory files must exist
978
** in order for the database to be readable.  The fourth parameter to
979
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
980
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
981
** WAL mode.  If the integer is -1, then it is overwritten with the current
982
** WAL persistence setting.
983
**
984
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
985
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
986
** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
987
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
988
** xDeviceCharacteristics methods. The fourth parameter to
989
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
990
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
991
** mode.  If the integer is -1, then it is overwritten with the current
992
** zero-damage mode setting.
993
**
994
** <li>[[SQLITE_FCNTL_OVERWRITE]]
995
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
996
** a write transaction to indicate that, unless it is rolled back for some
997
** reason, the entire database file will be overwritten by the current
998
** transaction. This is used by VACUUM operations.
999
**
1000
** <li>[[SQLITE_FCNTL_VFSNAME]]
1001
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
1002
** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
1003
** final bottom-level VFS are written into memory obtained from
1004
** [sqlite3_malloc()] and the result is stored in the char* variable
1005
** that the fourth parameter of [sqlite3_file_control()] points to.
1006
** The caller is responsible for freeing the memory when done.  As with
1007
** all file-control actions, there is no guarantee that this will actually
1008
** do anything.  Callers should initialize the char* variable to a NULL
1009
** pointer in case this file-control is not implemented.  This file-control
1010
** is intended for diagnostic use only.
1011
**
1012
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
1013
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
1014
** [VFSes] currently in use.  ^(The argument X in
1015
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
1016
** of type "[sqlite3_vfs] **".  This opcodes will set *X
1017
** to a pointer to the top-level VFS.)^
1018
** ^When there are multiple VFS shims in the stack, this opcode finds the
1019
** upper-most shim only.
1020
**
1021
** <li>[[SQLITE_FCNTL_PRAGMA]]
1022
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1023
** file control is sent to the open [sqlite3_file] object corresponding
1024
** to the database file to which the pragma statement refers. ^The argument
1025
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1026
** pointers to strings (char**) in which the second element of the array
1027
** is the name of the pragma and the third element is the argument to the
1028
** pragma or NULL if the pragma has no argument.  ^The handler for an
1029
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1030
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1031
** or the equivalent and that string will become the result of the pragma or
1032
** the error message if the pragma fails. ^If the
1033
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1034
** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
1035
** file control returns [SQLITE_OK], then the parser assumes that the
1036
** VFS has handled the PRAGMA itself and the parser generates a no-op
1037
** prepared statement if result string is NULL, or that returns a copy
1038
** of the result string if the string is non-NULL.
1039
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1040
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1041
** that the VFS encountered an error while handling the [PRAGMA] and the
1042
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
1043
** file control occurs at the beginning of pragma statement analysis and so
1044
** it is able to override built-in [PRAGMA] statements.
1045
**
1046
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1047
** ^The [SQLITE_FCNTL_BUSYHANDLER]
1048
** file-control may be invoked by SQLite on the database file handle
1049
** shortly after it is opened in order to provide a custom VFS with access
1050
** to the connection's busy-handler callback. The argument is of type (void**)
1051
** - an array of two (void *) values. The first (void *) actually points
1052
** to a function of type (int (*)(void *)). In order to invoke the connection's
1053
** busy-handler, this function should be invoked with the second (void *) in
1054
** the array as the only argument. If it returns non-zero, then the operation
1055
** should be retried. If it returns zero, the custom VFS should abandon the
1056
** current operation.
1057
**
1058
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1059
** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1060
** to have SQLite generate a
1061
** temporary filename using the same algorithm that is followed to generate
1062
** temporary filenames for TEMP tables and other internal uses.  The
1063
** argument should be a char** which will be filled with the filename
1064
** written into memory obtained from [sqlite3_malloc()].  The caller should
1065
** invoke [sqlite3_free()] on the result to avoid a memory leak.
1066
**
1067
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1068
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1069
** maximum number of bytes that will be used for memory-mapped I/O.
1070
** The argument is a pointer to a value of type sqlite3_int64 that
1071
** is an advisory maximum number of bytes in the file to memory map.  The
1072
** pointer is overwritten with the old value.  The limit is not changed if
1073
** the value originally pointed to is negative, and so the current limit
1074
** can be queried by passing in a pointer to a negative number.  This
1075
** file-control is used internally to implement [PRAGMA mmap_size].
1076
**
1077
** <li>[[SQLITE_FCNTL_TRACE]]
1078
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1079
** to the VFS about what the higher layers of the SQLite stack are doing.
1080
** This file control is used by some VFS activity tracing [shims].
1081
** The argument is a zero-terminated string.  Higher layers in the
1082
** SQLite stack may generate instances of this file control if
1083
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1084
**
1085
** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1086
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1087
** pointer to an integer and it writes a boolean into that integer depending
1088
** on whether or not the file has been renamed, moved, or deleted since it
1089
** was first opened.
1090
**
1091
** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1092
** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1093
** underlying native file handle associated with a file handle.  This file
1094
** control interprets its argument as a pointer to a native file handle and
1095
** writes the resulting value there.
1096
**
1097
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1098
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
1099
** opcode causes the xFileControl method to swap the file handle with the one
1100
** pointed to by the pArg argument.  This capability is used during testing
1101
** and only needs to be supported when SQLITE_TEST is defined.
1102
**
1103
** <li>[[SQLITE_FCNTL_NULL_IO]]
1104
** The [SQLITE_FCNTL_NULL_IO] opcode sets the low-level file descriptor
1105
** or file handle for the [sqlite3_file] object such that it will no longer
1106
** read or write to the database file.
1107
**
1108
** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1109
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1110
** be advantageous to block on the next WAL lock if the lock is not immediately
1111
** available.  The WAL subsystem issues this signal during rare
1112
** circumstances in order to fix a problem with priority inversion.
1113
** Applications should <em>not</em> use this file-control.
1114
**
1115
** <li>[[SQLITE_FCNTL_ZIPVFS]]
1116
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1117
** VFS should return SQLITE_NOTFOUND for this opcode.
1118
**
1119
** <li>[[SQLITE_FCNTL_RBU]]
1120
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1121
** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
1122
** this opcode.
1123
**
1124
** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1125
** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1126
** the file descriptor is placed in "batch write mode", which
1127
** means all subsequent write operations will be deferred and done
1128
** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].  Systems
1129
** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1130
** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1131
** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1132
** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1133
** no VFS interface calls on the same [sqlite3_file] file descriptor
1134
** except for calls to the xWrite method and the xFileControl method
1135
** with [SQLITE_FCNTL_SIZE_HINT].
1136
**
1137
** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1138
** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1139
** operations since the previous successful call to
1140
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1141
** This file control returns [SQLITE_OK] if and only if the writes were
1142
** all performed successfully and have been committed to persistent storage.
1143
** ^Regardless of whether or not it is successful, this file control takes
1144
** the file descriptor out of batch write mode so that all subsequent
1145
** write operations are independent.
1146
** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1147
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1148
**
1149
** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1150
** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1151
** operations since the previous successful call to
1152
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1153
** ^This file control takes the file descriptor out of batch write mode
1154
** so that all subsequent write operations are independent.
1155
** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1156
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1157
**
1158
** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1159
** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
1160
** to block for up to M milliseconds before failing when attempting to
1161
** obtain a file lock using the xLock or xShmLock methods of the VFS.
1162
** The parameter is a pointer to a 32-bit signed integer that contains
1163
** the value that M is to be set to. Before returning, the 32-bit signed
1164
** integer is overwritten with the previous value of M.
1165
**
1166
** <li>[[SQLITE_FCNTL_BLOCK_ON_CONNECT]]
1167
** The [SQLITE_FCNTL_BLOCK_ON_CONNECT] opcode is used to configure the
1168
** VFS to block when taking a SHARED lock to connect to a wal mode database.
1169
** This is used to implement the functionality associated with
1170
** SQLITE_SETLK_BLOCK_ON_CONNECT.
1171
**
1172
** <li>[[SQLITE_FCNTL_DATA_VERSION]]
1173
** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
1174
** a database file.  The argument is a pointer to a 32-bit unsigned integer.
1175
** The "data version" for the pager is written into the pointer.  The
1176
** "data version" changes whenever any change occurs to the corresponding
1177
** database file, either through SQL statements on the same database
1178
** connection or through transactions committed by separate database
1179
** connections possibly in other processes. The [sqlite3_total_changes()]
1180
** interface can be used to find if any database on the connection has changed,
1181
** but that interface responds to changes on TEMP as well as MAIN and does
1182
** not provide a mechanism to detect changes to MAIN only.  Also, the
1183
** [sqlite3_total_changes()] interface responds to internal changes only and
1184
** omits changes made by other database connections.  The
1185
** [PRAGMA data_version] command provides a mechanism to detect changes to
1186
** a single attached database that occur due to other database connections,
1187
** but omits changes implemented by the database connection on which it is
1188
** called.  This file control is the only mechanism to detect changes that
1189
** happen either internally or externally and that are associated with
1190
** a particular attached database.
1191
**
1192
** <li>[[SQLITE_FCNTL_CKPT_START]]
1193
** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
1194
** in wal mode before the client starts to copy pages from the wal
1195
** file to the database file.
1196
**
1197
** <li>[[SQLITE_FCNTL_CKPT_DONE]]
1198
** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
1199
** in wal mode after the client has finished copying pages from the wal
1200
** file to the database file, but before the *-shm file is updated to
1201
** record the fact that the pages have been checkpointed.
1202
**
1203
** <li>[[SQLITE_FCNTL_EXTERNAL_READER]]
1204
** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect
1205
** whether or not there is a database client in another process with a wal-mode
1206
** transaction open on the database or not. It is only available on unix.The
1207
** (void*) argument passed with this file-control should be a pointer to a
1208
** value of type (int). The integer value is set to 1 if the database is a wal
1209
** mode database and there exists at least one client in another process that
1210
** currently has an SQL transaction open on the database. It is set to 0 if
1211
** the database is not a wal-mode db, or if there is no such connection in any
1212
** other process. This opcode cannot be used to detect transactions opened
1213
** by clients within the current process, only within other processes.
1214
**
1215
** <li>[[SQLITE_FCNTL_CKSM_FILE]]
1216
** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the
1217
** [checksum VFS shim] only.
1218
**
1219
** <li>[[SQLITE_FCNTL_RESET_CACHE]]
1220
** If there is currently no transaction open on the database, and the
1221
** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control
1222
** purges the contents of the in-memory page cache. If there is an open
1223
** transaction, or if the db is a temp-db, this opcode is a no-op, not an error.
1224
** </ul>
1225
*/
1226
#define SQLITE_FCNTL_LOCKSTATE               1
1227
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
1228
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
1229
#define SQLITE_FCNTL_LAST_ERRNO              4
1230
#define SQLITE_FCNTL_SIZE_HINT               5
1231
#define SQLITE_FCNTL_CHUNK_SIZE              6
1232
#define SQLITE_FCNTL_FILE_POINTER            7
1233
#define SQLITE_FCNTL_SYNC_OMITTED            8
1234
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
1235
#define SQLITE_FCNTL_PERSIST_WAL            10
1236
#define SQLITE_FCNTL_OVERWRITE              11
1237
#define SQLITE_FCNTL_VFSNAME                12
1238
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
1239
#define SQLITE_FCNTL_PRAGMA                 14
1240
#define SQLITE_FCNTL_BUSYHANDLER            15
1241
#define SQLITE_FCNTL_TEMPFILENAME           16
1242
#define SQLITE_FCNTL_MMAP_SIZE              18
1243
#define SQLITE_FCNTL_TRACE                  19
1244
#define SQLITE_FCNTL_HAS_MOVED              20
1245
#define SQLITE_FCNTL_SYNC                   21
1246
#define SQLITE_FCNTL_COMMIT_PHASETWO        22
1247
#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
1248
#define SQLITE_FCNTL_WAL_BLOCK              24
1249
#define SQLITE_FCNTL_ZIPVFS                 25
1250
#define SQLITE_FCNTL_RBU                    26
1251
#define SQLITE_FCNTL_VFS_POINTER            27
1252
#define SQLITE_FCNTL_JOURNAL_POINTER        28
1253
#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
1254
#define SQLITE_FCNTL_PDB                    30
1255
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
1256
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
1257
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
1258
#define SQLITE_FCNTL_LOCK_TIMEOUT           34
1259
#define SQLITE_FCNTL_DATA_VERSION           35
1260
#define SQLITE_FCNTL_SIZE_LIMIT             36
1261
#define SQLITE_FCNTL_CKPT_DONE              37
1262
#define SQLITE_FCNTL_RESERVE_BYTES          38
1263
#define SQLITE_FCNTL_CKPT_START             39
1264
#define SQLITE_FCNTL_EXTERNAL_READER        40
1265
#define SQLITE_FCNTL_CKSM_FILE              41
1266
#define SQLITE_FCNTL_RESET_CACHE            42
1267
#define SQLITE_FCNTL_NULL_IO                43
1268
#define SQLITE_FCNTL_BLOCK_ON_CONNECT       44
1269
1270
/* deprecated names */
1271
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
1272
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
1273
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO
1274
1275
1276
/*
1277
** CAPI3REF: Mutex Handle
1278
**
1279
** The mutex module within SQLite defines [sqlite3_mutex] to be an
1280
** abstract type for a mutex object.  The SQLite core never looks
1281
** at the internal representation of an [sqlite3_mutex].  It only
1282
** deals with pointers to the [sqlite3_mutex] object.
1283
**
1284
** Mutexes are created using [sqlite3_mutex_alloc()].
1285
*/
1286
typedef struct sqlite3_mutex sqlite3_mutex;
1287
1288
/*
1289
** CAPI3REF: Loadable Extension Thunk
1290
**
1291
** A pointer to the opaque sqlite3_api_routines structure is passed as
1292
** the third parameter to entry points of [loadable extensions].  This
1293
** structure must be typedefed in order to work around compiler warnings
1294
** on some platforms.
1295
*/
1296
typedef struct sqlite3_api_routines sqlite3_api_routines;
1297
1298
/*
1299
** CAPI3REF: File Name
1300
**
1301
** Type [sqlite3_filename] is used by SQLite to pass filenames to the
1302
** xOpen method of a [VFS]. It may be cast to (const char*) and treated
1303
** as a normal, nul-terminated, UTF-8 buffer containing the filename, but
1304
** may also be passed to special APIs such as:
1305
**
1306
** <ul>
1307
** <li>  sqlite3_filename_database()
1308
** <li>  sqlite3_filename_journal()
1309
** <li>  sqlite3_filename_wal()
1310
** <li>  sqlite3_uri_parameter()
1311
** <li>  sqlite3_uri_boolean()
1312
** <li>  sqlite3_uri_int64()
1313
** <li>  sqlite3_uri_key()
1314
** </ul>
1315
*/
1316
typedef const char *sqlite3_filename;
1317
1318
/*
1319
** CAPI3REF: OS Interface Object
1320
**
1321
** An instance of the sqlite3_vfs object defines the interface between
1322
** the SQLite core and the underlying operating system.  The "vfs"
1323
** in the name of the object stands for "virtual file system".  See
1324
** the [VFS | VFS documentation] for further information.
1325
**
1326
** The VFS interface is sometimes extended by adding new methods onto
1327
** the end.  Each time such an extension occurs, the iVersion field
1328
** is incremented.  The iVersion value started out as 1 in
1329
** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1330
** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1331
** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6].  Additional fields
1332
** may be appended to the sqlite3_vfs object and the iVersion value
1333
** may increase again in future versions of SQLite.
1334
** Note that due to an oversight, the structure
1335
** of the sqlite3_vfs object changed in the transition from
1336
** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1337
** and yet the iVersion field was not increased.
1338
**
1339
** The szOsFile field is the size of the subclassed [sqlite3_file]
1340
** structure used by this VFS.  mxPathname is the maximum length of
1341
** a pathname in this VFS.
1342
**
1343
** Registered sqlite3_vfs objects are kept on a linked list formed by
1344
** the pNext pointer.  The [sqlite3_vfs_register()]
1345
** and [sqlite3_vfs_unregister()] interfaces manage this list
1346
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
1347
** searches the list.  Neither the application code nor the VFS
1348
** implementation should use the pNext pointer.
1349
**
1350
** The pNext field is the only field in the sqlite3_vfs
1351
** structure that SQLite will ever modify.  SQLite will only access
1352
** or modify this field while holding a particular static mutex.
1353
** The application should never modify anything within the sqlite3_vfs
1354
** object once the object has been registered.
1355
**
1356
** The zName field holds the name of the VFS module.  The name must
1357
** be unique across all VFS modules.
1358
**
1359
** [[sqlite3_vfs.xOpen]]
1360
** ^SQLite guarantees that the zFilename parameter to xOpen
1361
** is either a NULL pointer or string obtained
1362
** from xFullPathname() with an optional suffix added.
1363
** ^If a suffix is added to the zFilename parameter, it will
1364
** consist of a single "-" character followed by no more than
1365
** 11 alphanumeric and/or "-" characters.
1366
** ^SQLite further guarantees that
1367
** the string will be valid and unchanged until xClose() is
1368
** called. Because of the previous sentence,
1369
** the [sqlite3_file] can safely store a pointer to the
1370
** filename if it needs to remember the filename for some reason.
1371
** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1372
** must invent its own temporary name for the file.  ^Whenever the
1373
** xFilename parameter is NULL it will also be the case that the
1374
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1375
**
1376
** The flags argument to xOpen() includes all bits set in
1377
** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
1378
** or [sqlite3_open16()] is used, then flags includes at least
1379
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1380
** If xOpen() opens a file read-only then it sets *pOutFlags to
1381
** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1382
**
1383
** ^(SQLite will also add one of the following flags to the xOpen()
1384
** call, depending on the object being opened:
1385
**
1386
** <ul>
1387
** <li>  [SQLITE_OPEN_MAIN_DB]
1388
** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
1389
** <li>  [SQLITE_OPEN_TEMP_DB]
1390
** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
1391
** <li>  [SQLITE_OPEN_TRANSIENT_DB]
1392
** <li>  [SQLITE_OPEN_SUBJOURNAL]
1393
** <li>  [SQLITE_OPEN_SUPER_JOURNAL]
1394
** <li>  [SQLITE_OPEN_WAL]
1395
** </ul>)^
1396
**
1397
** The file I/O implementation can use the object type flags to
1398
** change the way it deals with files.  For example, an application
1399
** that does not care about crash recovery or rollback might make
1400
** the open of a journal file a no-op.  Writes to this journal would
1401
** also be no-ops, and any attempt to read the journal would return
1402
** SQLITE_IOERR.  Or the implementation might recognize that a database
1403
** file will be doing page-aligned sector reads and writes in a random
1404
** order and set up its I/O subsystem accordingly.
1405
**
1406
** SQLite might also add one of the following flags to the xOpen method:
1407
**
1408
** <ul>
1409
** <li> [SQLITE_OPEN_DELETEONCLOSE]
1410
** <li> [SQLITE_OPEN_EXCLUSIVE]
1411
** </ul>
1412
**
1413
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1414
** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1415
** will be set for TEMP databases and their journals, transient
1416
** databases, and subjournals.
1417
**
1418
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1419
** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1420
** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1421
** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1422
** SQLITE_OPEN_CREATE, is used to indicate that file should always
1423
** be created, and that it is an error if it already exists.
1424
** It is <i>not</i> used to indicate the file should be opened
1425
** for exclusive access.
1426
**
1427
** ^At least szOsFile bytes of memory are allocated by SQLite
1428
** to hold the [sqlite3_file] structure passed as the third
1429
** argument to xOpen.  The xOpen method does not have to
1430
** allocate the structure; it should just fill it in.  Note that
1431
** the xOpen method must set the sqlite3_file.pMethods to either
1432
** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1433
** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1434
** element will be valid after xOpen returns regardless of the success
1435
** or failure of the xOpen call.
1436
**
1437
** [[sqlite3_vfs.xAccess]]
1438
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1439
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1440
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1441
** to test whether a file is at least readable.  The SQLITE_ACCESS_READ
1442
** flag is never actually used and is not implemented in the built-in
1443
** VFSes of SQLite.  The file is named by the second argument and can be a
1444
** directory. The xAccess method returns [SQLITE_OK] on success or some
1445
** non-zero error code if there is an I/O error or if the name of
1446
** the file given in the second argument is illegal.  If SQLITE_OK
1447
** is returned, then non-zero or zero is written into *pResOut to indicate
1448
** whether or not the file is accessible.
1449
**
1450
** ^SQLite will always allocate at least mxPathname+1 bytes for the
1451
** output buffer xFullPathname.  The exact size of the output buffer
1452
** is also passed as a parameter to both  methods. If the output buffer
1453
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1454
** handled as a fatal error by SQLite, vfs implementations should endeavor
1455
** to prevent this by setting mxPathname to a sufficiently large value.
1456
**
1457
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1458
** interfaces are not strictly a part of the filesystem, but they are
1459
** included in the VFS structure for completeness.
1460
** The xRandomness() function attempts to return nBytes bytes
1461
** of good-quality randomness into zOut.  The return value is
1462
** the actual number of bytes of randomness obtained.
1463
** The xSleep() method causes the calling thread to sleep for at
1464
** least the number of microseconds given.  ^The xCurrentTime()
1465
** method returns a Julian Day Number for the current date and time as
1466
** a floating point value.
1467
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1468
** Day Number multiplied by 86400000 (the number of milliseconds in
1469
** a 24-hour day).
1470
** ^SQLite will use the xCurrentTimeInt64() method to get the current
1471
** date and time if that method is available (if iVersion is 2 or
1472
** greater and the function pointer is not NULL) and will fall back
1473
** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1474
**
1475
** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1476
** are not used by the SQLite core.  These optional interfaces are provided
1477
** by some VFSes to facilitate testing of the VFS code. By overriding
1478
** system calls with functions under its control, a test program can
1479
** simulate faults and error conditions that would otherwise be difficult
1480
** or impossible to induce.  The set of system calls that can be overridden
1481
** varies from one VFS to another, and from one version of the same VFS to the
1482
** next.  Applications that use these interfaces must be prepared for any
1483
** or all of these interfaces to be NULL or for their behavior to change
1484
** from one release to the next.  Applications must not attempt to access
1485
** any of these methods if the iVersion of the VFS is less than 3.
1486
*/
1487
typedef struct sqlite3_vfs sqlite3_vfs;
1488
typedef void (*sqlite3_syscall_ptr)(void);
1489
struct sqlite3_vfs {
1490
  int iVersion;            /* Structure version number (currently 3) */
1491
  int szOsFile;            /* Size of subclassed sqlite3_file */
1492
  int mxPathname;          /* Maximum file pathname length */
1493
  sqlite3_vfs *pNext;      /* Next registered VFS */
1494
  const char *zName;       /* Name of this virtual file system */
1495
  void *pAppData;          /* Pointer to application-specific data */
1496
  int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*,
1497
               int flags, int *pOutFlags);
1498
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1499
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1500
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1501
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1502
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1503
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1504
  void (*xDlClose)(sqlite3_vfs*, void*);
1505
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1506
  int (*xSleep)(sqlite3_vfs*, int microseconds);
1507
  int (*xCurrentTime)(sqlite3_vfs*, double*);
1508
  int (*xGetLastError)(sqlite3_vfs*, int, char *);
1509
  /*
1510
  ** The methods above are in version 1 of the sqlite_vfs object
1511
  ** definition.  Those that follow are added in version 2 or later
1512
  */
1513
  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1514
  /*
1515
  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1516
  ** Those below are for version 3 and greater.
1517
  */
1518
  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1519
  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1520
  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1521
  /*
1522
  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1523
  ** New fields may be appended in future versions.  The iVersion
1524
  ** value will increment whenever this happens.
1525
  */
1526
};
1527
1528
/*
1529
** CAPI3REF: Flags for the xAccess VFS method
1530
**
1531
** These integer constants can be used as the third parameter to
1532
** the xAccess method of an [sqlite3_vfs] object.  They determine
1533
** what kind of permissions the xAccess method is looking for.
1534
** With SQLITE_ACCESS_EXISTS, the xAccess method
1535
** simply checks whether the file exists.
1536
** With SQLITE_ACCESS_READWRITE, the xAccess method
1537
** checks whether the named directory is both readable and writable
1538
** (in other words, if files can be added, removed, and renamed within
1539
** the directory).
1540
** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1541
** [temp_store_directory pragma], though this could change in a future
1542
** release of SQLite.
1543
** With SQLITE_ACCESS_READ, the xAccess method
1544
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1545
** currently unused, though it might be used in a future release of
1546
** SQLite.
1547
*/
1548
#define SQLITE_ACCESS_EXISTS    0
1549
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
1550
#define SQLITE_ACCESS_READ      2   /* Unused */
1551
1552
/*
1553
** CAPI3REF: Flags for the xShmLock VFS method
1554
**
1555
** These integer constants define the various locking operations
1556
** allowed by the xShmLock method of [sqlite3_io_methods].  The
1557
** following are the only legal combinations of flags to the
1558
** xShmLock method:
1559
**
1560
** <ul>
1561
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1562
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1563
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1564
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1565
** </ul>
1566
**
1567
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1568
** was given on the corresponding lock.
1569
**
1570
** The xShmLock method can transition between unlocked and SHARED or
1571
** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
1572
** and EXCLUSIVE.
1573
*/
1574
#define SQLITE_SHM_UNLOCK       1
1575
#define SQLITE_SHM_LOCK         2
1576
#define SQLITE_SHM_SHARED       4
1577
#define SQLITE_SHM_EXCLUSIVE    8
1578
1579
/*
1580
** CAPI3REF: Maximum xShmLock index
1581
**
1582
** The xShmLock method on [sqlite3_io_methods] may use values
1583
** between 0 and this upper bound as its "offset" argument.
1584
** The SQLite core will never attempt to acquire or release a
1585
** lock outside of this range
1586
*/
1587
#define SQLITE_SHM_NLOCK        8
1588
1589
1590
/*
1591
** CAPI3REF: Initialize The SQLite Library
1592
**
1593
** ^The sqlite3_initialize() routine initializes the
1594
** SQLite library.  ^The sqlite3_shutdown() routine
1595
** deallocates any resources that were allocated by sqlite3_initialize().
1596
** These routines are designed to aid in process initialization and
1597
** shutdown on embedded systems.  Workstation applications using
1598
** SQLite normally do not need to invoke either of these routines.
1599
**
1600
** A call to sqlite3_initialize() is an "effective" call if it is
1601
** the first time sqlite3_initialize() is invoked during the lifetime of
1602
** the process, or if it is the first time sqlite3_initialize() is invoked
1603
** following a call to sqlite3_shutdown().  ^(Only an effective call
1604
** of sqlite3_initialize() does any initialization.  All other calls
1605
** are harmless no-ops.)^
1606
**
1607
** A call to sqlite3_shutdown() is an "effective" call if it is the first
1608
** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1609
** an effective call to sqlite3_shutdown() does any deinitialization.
1610
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1611
**
1612
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1613
** is not.  The sqlite3_shutdown() interface must only be called from a
1614
** single thread.  All open [database connections] must be closed and all
1615
** other SQLite resources must be deallocated prior to invoking
1616
** sqlite3_shutdown().
1617
**
1618
** Among other things, ^sqlite3_initialize() will invoke
1619
** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1620
** will invoke sqlite3_os_end().
1621
**
1622
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1623
** ^If for some reason, sqlite3_initialize() is unable to initialize
1624
** the library (perhaps it is unable to allocate a needed resource such
1625
** as a mutex) it returns an [error code] other than [SQLITE_OK].
1626
**
1627
** ^The sqlite3_initialize() routine is called internally by many other
1628
** SQLite interfaces so that an application usually does not need to
1629
** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1630
** calls sqlite3_initialize() so the SQLite library will be automatically
1631
** initialized when [sqlite3_open()] is called if it has not be initialized
1632
** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1633
** compile-time option, then the automatic calls to sqlite3_initialize()
1634
** are omitted and the application must call sqlite3_initialize() directly
1635
** prior to using any other SQLite interface.  For maximum portability,
1636
** it is recommended that applications always invoke sqlite3_initialize()
1637
** directly prior to using any other SQLite interface.  Future releases
1638
** of SQLite may require this.  In other words, the behavior exhibited
1639
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1640
** default behavior in some future release of SQLite.
1641
**
1642
** The sqlite3_os_init() routine does operating-system specific
1643
** initialization of the SQLite library.  The sqlite3_os_end()
1644
** routine undoes the effect of sqlite3_os_init().  Typical tasks
1645
** performed by these routines include allocation or deallocation
1646
** of static resources, initialization of global variables,
1647
** setting up a default [sqlite3_vfs] module, or setting up
1648
** a default configuration using [sqlite3_config()].
1649
**
1650
** The application should never invoke either sqlite3_os_init()
1651
** or sqlite3_os_end() directly.  The application should only invoke
1652
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1653
** interface is called automatically by sqlite3_initialize() and
1654
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1655
** implementations for sqlite3_os_init() and sqlite3_os_end()
1656
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1657
** When [custom builds | built for other platforms]
1658
** (using the [SQLITE_OS_OTHER=1] compile-time
1659
** option) the application must supply a suitable implementation for
1660
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1661
** implementation of sqlite3_os_init() or sqlite3_os_end()
1662
** must return [SQLITE_OK] on success and some other [error code] upon
1663
** failure.
1664
*/
1665
SQLITE_API int sqlite3_initialize(void);
1666
SQLITE_API int sqlite3_shutdown(void);
1667
SQLITE_API int sqlite3_os_init(void);
1668
SQLITE_API int sqlite3_os_end(void);
1669
1670
/*
1671
** CAPI3REF: Configuring The SQLite Library
1672
**
1673
** The sqlite3_config() interface is used to make global configuration
1674
** changes to SQLite in order to tune SQLite to the specific needs of
1675
** the application.  The default configuration is recommended for most
1676
** applications and so this routine is usually not necessary.  It is
1677
** provided to support rare applications with unusual needs.
1678
**
1679
** <b>The sqlite3_config() interface is not threadsafe. The application
1680
** must ensure that no other SQLite interfaces are invoked by other
1681
** threads while sqlite3_config() is running.</b>
1682
**
1683
** The first argument to sqlite3_config() is an integer
1684
** [configuration option] that determines
1685
** what property of SQLite is to be configured.  Subsequent arguments
1686
** vary depending on the [configuration option]
1687
** in the first argument.
1688
**
1689
** For most configuration options, the sqlite3_config() interface
1690
** may only be invoked prior to library initialization using
1691
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1692
** The exceptional configuration options that may be invoked at any time
1693
** are called "anytime configuration options".
1694
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1695
** [sqlite3_shutdown()] with a first argument that is not an anytime
1696
** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE.
1697
** Note, however, that ^sqlite3_config() can be called as part of the
1698
** implementation of an application-defined [sqlite3_os_init()].
1699
**
1700
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1701
** ^If the option is unknown or SQLite is unable to set the option
1702
** then this routine returns a non-zero [error code].
1703
*/
1704
SQLITE_API int sqlite3_config(int, ...);
1705
1706
/*
1707
** CAPI3REF: Configure database connections
1708
** METHOD: sqlite3
1709
**
1710
** The sqlite3_db_config() interface is used to make configuration
1711
** changes to a [database connection].  The interface is similar to
1712
** [sqlite3_config()] except that the changes apply to a single
1713
** [database connection] (specified in the first argument).
1714
**
1715
** The second argument to sqlite3_db_config(D,V,...)  is the
1716
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1717
** that indicates what aspect of the [database connection] is being configured.
1718
** Subsequent arguments vary depending on the configuration verb.
1719
**
1720
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1721
** the call is considered successful.
1722
*/
1723
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1724
1725
/*
1726
** CAPI3REF: Memory Allocation Routines
1727
**
1728
** An instance of this object defines the interface between SQLite
1729
** and low-level memory allocation routines.
1730
**
1731
** This object is used in only one place in the SQLite interface.
1732
** A pointer to an instance of this object is the argument to
1733
** [sqlite3_config()] when the configuration option is
1734
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1735
** By creating an instance of this object
1736
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1737
** during configuration, an application can specify an alternative
1738
** memory allocation subsystem for SQLite to use for all of its
1739
** dynamic memory needs.
1740
**
1741
** Note that SQLite comes with several [built-in memory allocators]
1742
** that are perfectly adequate for the overwhelming majority of applications
1743
** and that this object is only useful to a tiny minority of applications
1744
** with specialized memory allocation requirements.  This object is
1745
** also used during testing of SQLite in order to specify an alternative
1746
** memory allocator that simulates memory out-of-memory conditions in
1747
** order to verify that SQLite recovers gracefully from such
1748
** conditions.
1749
**
1750
** The xMalloc, xRealloc, and xFree methods must work like the
1751
** malloc(), realloc() and free() functions from the standard C library.
1752
** ^SQLite guarantees that the second argument to
1753
** xRealloc is always a value returned by a prior call to xRoundup.
1754
**
1755
** xSize should return the allocated size of a memory allocation
1756
** previously obtained from xMalloc or xRealloc.  The allocated size
1757
** is always at least as big as the requested size but may be larger.
1758
**
1759
** The xRoundup method returns what would be the allocated size of
1760
** a memory allocation given a particular requested size.  Most memory
1761
** allocators round up memory allocations at least to the next multiple
1762
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1763
** Every memory allocation request coming in through [sqlite3_malloc()]
1764
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0,
1765
** that causes the corresponding memory allocation to fail.
1766
**
1767
** The xInit method initializes the memory allocator.  For example,
1768
** it might allocate any required mutexes or initialize internal data
1769
** structures.  The xShutdown method is invoked (indirectly) by
1770
** [sqlite3_shutdown()] and should deallocate any resources acquired
1771
** by xInit.  The pAppData pointer is used as the only parameter to
1772
** xInit and xShutdown.
1773
**
1774
** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
1775
** the xInit method, so the xInit method need not be threadsafe.  The
1776
** xShutdown method is only called from [sqlite3_shutdown()] so it does
1777
** not need to be threadsafe either.  For all other methods, SQLite
1778
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1779
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1780
** it is by default) and so the methods are automatically serialized.
1781
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1782
** methods must be threadsafe or else make their own arrangements for
1783
** serialization.
1784
**
1785
** SQLite will never invoke xInit() more than once without an intervening
1786
** call to xShutdown().
1787
*/
1788
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1789
struct sqlite3_mem_methods {
1790
  void *(*xMalloc)(int);         /* Memory allocation function */
1791
  void (*xFree)(void*);          /* Free a prior allocation */
1792
  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1793
  int (*xSize)(void*);           /* Return the size of an allocation */
1794
  int (*xRoundup)(int);          /* Round up request size to allocation size */
1795
  int (*xInit)(void*);           /* Initialize the memory allocator */
1796
  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1797
  void *pAppData;                /* Argument to xInit() and xShutdown() */
1798
};
1799
1800
/*
1801
** CAPI3REF: Configuration Options
1802
** KEYWORDS: {configuration option}
1803
**
1804
** These constants are the available integer configuration options that
1805
** can be passed as the first argument to the [sqlite3_config()] interface.
1806
**
1807
** Most of the configuration options for sqlite3_config()
1808
** will only work if invoked prior to [sqlite3_initialize()] or after
1809
** [sqlite3_shutdown()].  The few exceptions to this rule are called
1810
** "anytime configuration options".
1811
** ^Calling [sqlite3_config()] with a first argument that is not an
1812
** anytime configuration option in between calls to [sqlite3_initialize()] and
1813
** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE.
1814
**
1815
** The set of anytime configuration options can change (by insertions
1816
** and/or deletions) from one release of SQLite to the next.
1817
** As of SQLite version 3.42.0, the complete set of anytime configuration
1818
** options is:
1819
** <ul>
1820
** <li> SQLITE_CONFIG_LOG
1821
** <li> SQLITE_CONFIG_PCACHE_HDRSZ
1822
** </ul>
1823
**
1824
** New configuration options may be added in future releases of SQLite.
1825
** Existing configuration options might be discontinued.  Applications
1826
** should check the return code from [sqlite3_config()] to make sure that
1827
** the call worked.  The [sqlite3_config()] interface will return a
1828
** non-zero [error code] if a discontinued or unsupported configuration option
1829
** is invoked.
1830
**
1831
** <dl>
1832
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1833
** <dd>There are no arguments to this option.  ^This option sets the
1834
** [threading mode] to Single-thread.  In other words, it disables
1835
** all mutexing and puts SQLite into a mode where it can only be used
1836
** by a single thread.   ^If SQLite is compiled with
1837
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1838
** it is not possible to change the [threading mode] from its default
1839
** value of Single-thread and so [sqlite3_config()] will return
1840
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1841
** configuration option.</dd>
1842
**
1843
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1844
** <dd>There are no arguments to this option.  ^This option sets the
1845
** [threading mode] to Multi-thread.  In other words, it disables
1846
** mutexing on [database connection] and [prepared statement] objects.
1847
** The application is responsible for serializing access to
1848
** [database connections] and [prepared statements].  But other mutexes
1849
** are enabled so that SQLite will be safe to use in a multi-threaded
1850
** environment as long as no two threads attempt to use the same
1851
** [database connection] at the same time.  ^If SQLite is compiled with
1852
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1853
** it is not possible to set the Multi-thread [threading mode] and
1854
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1855
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1856
**
1857
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1858
** <dd>There are no arguments to this option.  ^This option sets the
1859
** [threading mode] to Serialized. In other words, this option enables
1860
** all mutexes including the recursive
1861
** mutexes on [database connection] and [prepared statement] objects.
1862
** In this mode (which is the default when SQLite is compiled with
1863
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1864
** to [database connections] and [prepared statements] so that the
1865
** application is free to use the same [database connection] or the
1866
** same [prepared statement] in different threads at the same time.
1867
** ^If SQLite is compiled with
1868
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1869
** it is not possible to set the Serialized [threading mode] and
1870
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1871
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1872
**
1873
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1874
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1875
** a pointer to an instance of the [sqlite3_mem_methods] structure.
1876
** The argument specifies
1877
** alternative low-level memory allocation routines to be used in place of
1878
** the memory allocation routines built into SQLite.)^ ^SQLite makes
1879
** its own private copy of the content of the [sqlite3_mem_methods] structure
1880
** before the [sqlite3_config()] call returns.</dd>
1881
**
1882
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1883
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1884
** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1885
** The [sqlite3_mem_methods]
1886
** structure is filled with the currently defined memory allocation routines.)^
1887
** This option can be used to overload the default memory allocation
1888
** routines with a wrapper that simulations memory allocation failure or
1889
** tracks memory usage, for example. </dd>
1890
**
1891
** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1892
** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
1893
** type int, interpreted as a boolean, which if true provides a hint to
1894
** SQLite that it should avoid large memory allocations if possible.
1895
** SQLite will run faster if it is free to make large memory allocations,
1896
** but some application might prefer to run slower in exchange for
1897
** guarantees about memory fragmentation that are possible if large
1898
** allocations are avoided.  This hint is normally off.
1899
** </dd>
1900
**
1901
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1902
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1903
** interpreted as a boolean, which enables or disables the collection of
1904
** memory allocation statistics. ^(When memory allocation statistics are
1905
** disabled, the following SQLite interfaces become non-operational:
1906
**   <ul>
1907
**   <li> [sqlite3_hard_heap_limit64()]
1908
**   <li> [sqlite3_memory_used()]
1909
**   <li> [sqlite3_memory_highwater()]
1910
**   <li> [sqlite3_soft_heap_limit64()]
1911
**   <li> [sqlite3_status64()]
1912
**   </ul>)^
1913
** ^Memory allocation statistics are enabled by default unless SQLite is
1914
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1915
** allocation statistics are disabled by default.
1916
** </dd>
1917
**
1918
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1919
** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1920
** </dd>
1921
**
1922
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1923
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1924
** that SQLite can use for the database page cache with the default page
1925
** cache implementation.
1926
** This configuration option is a no-op if an application-defined page
1927
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1928
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1929
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1930
** and the number of cache lines (N).
1931
** The sz argument should be the size of the largest database page
1932
** (a power of two between 512 and 65536) plus some extra bytes for each
1933
** page header.  ^The number of extra bytes needed by the page header
1934
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1935
** ^It is harmless, apart from the wasted memory,
1936
** for the sz parameter to be larger than necessary.  The pMem
1937
** argument must be either a NULL pointer or a pointer to an 8-byte
1938
** aligned block of memory of at least sz*N bytes, otherwise
1939
** subsequent behavior is undefined.
1940
** ^When pMem is not NULL, SQLite will strive to use the memory provided
1941
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1942
** a page cache line is larger than sz bytes or if all of the pMem buffer
1943
** is exhausted.
1944
** ^If pMem is NULL and N is non-zero, then each database connection
1945
** does an initial bulk allocation for page cache memory
1946
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1947
** of -1024*N bytes if N is negative, . ^If additional
1948
** page cache memory is needed beyond what is provided by the initial
1949
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1950
** additional cache line. </dd>
1951
**
1952
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1953
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1954
** that SQLite will use for all of its dynamic memory allocation needs
1955
** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1956
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1957
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1958
** [SQLITE_ERROR] if invoked otherwise.
1959
** ^There are three arguments to SQLITE_CONFIG_HEAP:
1960
** An 8-byte aligned pointer to the memory,
1961
** the number of bytes in the memory buffer, and the minimum allocation size.
1962
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1963
** to using its default memory allocator (the system malloc() implementation),
1964
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1965
** memory pointer is not NULL then the alternative memory
1966
** allocator is engaged to handle all of SQLites memory allocation needs.
1967
** The first pointer (the memory pointer) must be aligned to an 8-byte
1968
** boundary or subsequent behavior of SQLite will be undefined.
1969
** The minimum allocation size is capped at 2**12. Reasonable values
1970
** for the minimum allocation size are 2**5 through 2**8.</dd>
1971
**
1972
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1973
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1974
** pointer to an instance of the [sqlite3_mutex_methods] structure.
1975
** The argument specifies alternative low-level mutex routines to be used
1976
** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
1977
** the content of the [sqlite3_mutex_methods] structure before the call to
1978
** [sqlite3_config()] returns. ^If SQLite is compiled with
1979
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1980
** the entire mutexing subsystem is omitted from the build and hence calls to
1981
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1982
** return [SQLITE_ERROR].</dd>
1983
**
1984
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1985
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1986
** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1987
** [sqlite3_mutex_methods]
1988
** structure is filled with the currently defined mutex routines.)^
1989
** This option can be used to overload the default mutex allocation
1990
** routines with a wrapper used to track mutex usage for performance
1991
** profiling or testing, for example.   ^If SQLite is compiled with
1992
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1993
** the entire mutexing subsystem is omitted from the build and hence calls to
1994
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1995
** return [SQLITE_ERROR].</dd>
1996
**
1997
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1998
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1999
** the default size of [lookaside memory] on each [database connection].
2000
** The first argument is the
2001
** size of each lookaside buffer slot ("sz") and the second is the number of
2002
** slots allocated to each database connection ("cnt").)^
2003
** ^(SQLITE_CONFIG_LOOKASIDE sets the <i>default</i> lookaside size.
2004
** The [SQLITE_DBCONFIG_LOOKASIDE] option to [sqlite3_db_config()] can
2005
** be used to change the lookaside configuration on individual connections.)^
2006
** The [-DSQLITE_DEFAULT_LOOKASIDE] option can be used to change the
2007
** default lookaside configuration at compile-time.
2008
** </dd>
2009
**
2010
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
2011
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
2012
** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
2013
** the interface to a custom page cache implementation.)^
2014
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
2015
**
2016
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
2017
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
2018
** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
2019
** the current page cache implementation into that object.)^ </dd>
2020
**
2021
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
2022
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
2023
** global [error log].
2024
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
2025
** function with a call signature of void(*)(void*,int,const char*),
2026
** and a pointer to void. ^If the function pointer is not NULL, it is
2027
** invoked by [sqlite3_log()] to process each logging event.  ^If the
2028
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
2029
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
2030
** passed through as the first parameter to the application-defined logger
2031
** function whenever that function is invoked.  ^The second parameter to
2032
** the logger function is a copy of the first parameter to the corresponding
2033
** [sqlite3_log()] call and is intended to be a [result code] or an
2034
** [extended result code].  ^The third parameter passed to the logger is
2035
** log message after formatting via [sqlite3_snprintf()].
2036
** The SQLite logging interface is not reentrant; the logger function
2037
** supplied by the application must not invoke any SQLite interface.
2038
** In a multi-threaded application, the application-defined logger
2039
** function must be threadsafe. </dd>
2040
**
2041
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
2042
** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
2043
** If non-zero, then URI handling is globally enabled. If the parameter is zero,
2044
** then URI handling is globally disabled.)^ ^If URI handling is globally
2045
** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
2046
** [sqlite3_open16()] or
2047
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
2048
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
2049
** connection is opened. ^If it is globally disabled, filenames are
2050
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
2051
** database connection is opened. ^(By default, URI handling is globally
2052
** disabled. The default value may be changed by compiling with the
2053
** [SQLITE_USE_URI] symbol defined.)^
2054
**
2055
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
2056
** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
2057
** argument which is interpreted as a boolean in order to enable or disable
2058
** the use of covering indices for full table scans in the query optimizer.
2059
** ^The default setting is determined
2060
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
2061
** if that compile-time option is omitted.
2062
** The ability to disable the use of covering indices for full table scans
2063
** is because some incorrectly coded legacy applications might malfunction
2064
** when the optimization is enabled.  Providing the ability to
2065
** disable the optimization allows the older, buggy application code to work
2066
** without change even with newer versions of SQLite.
2067
**
2068
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
2069
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
2070
** <dd> These options are obsolete and should not be used by new code.
2071
** They are retained for backwards compatibility but are now no-ops.
2072
** </dd>
2073
**
2074
** [[SQLITE_CONFIG_SQLLOG]]
2075
** <dt>SQLITE_CONFIG_SQLLOG
2076
** <dd>This option is only available if sqlite is compiled with the
2077
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
2078
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
2079
** The second should be of type (void*). The callback is invoked by the library
2080
** in three separate circumstances, identified by the value passed as the
2081
** fourth parameter. If the fourth parameter is 0, then the database connection
2082
** passed as the second argument has just been opened. The third argument
2083
** points to a buffer containing the name of the main database file. If the
2084
** fourth parameter is 1, then the SQL statement that the third parameter
2085
** points to has just been executed. Or, if the fourth parameter is 2, then
2086
** the connection being passed as the second parameter is being closed. The
2087
** third parameter is passed NULL In this case.  An example of using this
2088
** configuration option can be seen in the "test_sqllog.c" source file in
2089
** the canonical SQLite source tree.</dd>
2090
**
2091
** [[SQLITE_CONFIG_MMAP_SIZE]]
2092
** <dt>SQLITE_CONFIG_MMAP_SIZE
2093
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
2094
** that are the default mmap size limit (the default setting for
2095
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
2096
** ^The default setting can be overridden by each database connection using
2097
** either the [PRAGMA mmap_size] command, or by using the
2098
** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
2099
** will be silently truncated if necessary so that it does not exceed the
2100
** compile-time maximum mmap size set by the
2101
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
2102
** ^If either argument to this option is negative, then that argument is
2103
** changed to its compile-time default.
2104
**
2105
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
2106
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
2107
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
2108
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
2109
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
2110
** that specifies the maximum size of the created heap.
2111
**
2112
** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
2113
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
2114
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
2115
** is a pointer to an integer and writes into that integer the number of extra
2116
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
2117
** The amount of extra space required can change depending on the compiler,
2118
** target platform, and SQLite version.
2119
**
2120
** [[SQLITE_CONFIG_PMASZ]]
2121
** <dt>SQLITE_CONFIG_PMASZ
2122
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
2123
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
2124
** sorter to that integer.  The default minimum PMA Size is set by the
2125
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
2126
** to help with sort operations when multithreaded sorting
2127
** is enabled (using the [PRAGMA threads] command) and the amount of content
2128
** to be sorted exceeds the page size times the minimum of the
2129
** [PRAGMA cache_size] setting and this value.
2130
**
2131
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
2132
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
2133
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
2134
** becomes the [statement journal] spill-to-disk threshold.
2135
** [Statement journals] are held in memory until their size (in bytes)
2136
** exceeds this threshold, at which point they are written to disk.
2137
** Or if the threshold is -1, statement journals are always held
2138
** exclusively in memory.
2139
** Since many statement journals never become large, setting the spill
2140
** threshold to a value such as 64KiB can greatly reduce the amount of
2141
** I/O required to support statement rollback.
2142
** The default value for this setting is controlled by the
2143
** [SQLITE_STMTJRNL_SPILL] compile-time option.
2144
**
2145
** [[SQLITE_CONFIG_SORTERREF_SIZE]]
2146
** <dt>SQLITE_CONFIG_SORTERREF_SIZE
2147
** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
2148
** of type (int) - the new value of the sorter-reference size threshold.
2149
** Usually, when SQLite uses an external sort to order records according
2150
** to an ORDER BY clause, all fields required by the caller are present in the
2151
** sorted records. However, if SQLite determines based on the declared type
2152
** of a table column that its values are likely to be very large - larger
2153
** than the configured sorter-reference size threshold - then a reference
2154
** is stored in each sorted record and the required column values loaded
2155
** from the database as records are returned in sorted order. The default
2156
** value for this option is to never use this optimization. Specifying a
2157
** negative value for this option restores the default behavior.
2158
** This option is only available if SQLite is compiled with the
2159
** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
2160
**
2161
** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
2162
** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
2163
** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
2164
** [sqlite3_int64] parameter which is the default maximum size for an in-memory
2165
** database created using [sqlite3_deserialize()].  This default maximum
2166
** size can be adjusted up or down for individual databases using the
2167
** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control].  If this
2168
** configuration setting is never used, then the default maximum is determined
2169
** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option.  If that
2170
** compile-time option is not set, then the default maximum is 1073741824.
2171
**
2172
** [[SQLITE_CONFIG_ROWID_IN_VIEW]]
2173
** <dt>SQLITE_CONFIG_ROWID_IN_VIEW
2174
** <dd>The SQLITE_CONFIG_ROWID_IN_VIEW option enables or disables the ability
2175
** for VIEWs to have a ROWID.  The capability can only be enabled if SQLite is
2176
** compiled with -DSQLITE_ALLOW_ROWID_IN_VIEW, in which case the capability
2177
** defaults to on.  This configuration option queries the current setting or
2178
** changes the setting to off or on.  The argument is a pointer to an integer.
2179
** If that integer initially holds a value of 1, then the ability for VIEWs to
2180
** have ROWIDs is activated.  If the integer initially holds zero, then the
2181
** ability is deactivated.  Any other initial value for the integer leaves the
2182
** setting unchanged.  After changes, if any, the integer is written with
2183
** a 1 or 0, if the ability for VIEWs to have ROWIDs is on or off.  If SQLite
2184
** is compiled without -DSQLITE_ALLOW_ROWID_IN_VIEW (which is the usual and
2185
** recommended case) then the integer is always filled with zero, regardless
2186
** if its initial value.
2187
** </dl>
2188
*/
2189
#define SQLITE_CONFIG_SINGLETHREAD         1  /* nil */
2190
#define SQLITE_CONFIG_MULTITHREAD          2  /* nil */
2191
#define SQLITE_CONFIG_SERIALIZED           3  /* nil */
2192
#define SQLITE_CONFIG_MALLOC               4  /* sqlite3_mem_methods* */
2193
#define SQLITE_CONFIG_GETMALLOC            5  /* sqlite3_mem_methods* */
2194
#define SQLITE_CONFIG_SCRATCH              6  /* No longer used */
2195
#define SQLITE_CONFIG_PAGECACHE            7  /* void*, int sz, int N */
2196
#define SQLITE_CONFIG_HEAP                 8  /* void*, int nByte, int min */
2197
#define SQLITE_CONFIG_MEMSTATUS            9  /* boolean */
2198
#define SQLITE_CONFIG_MUTEX               10  /* sqlite3_mutex_methods* */
2199
#define SQLITE_CONFIG_GETMUTEX            11  /* sqlite3_mutex_methods* */
2200
/* previously SQLITE_CONFIG_CHUNKALLOC    12 which is now unused. */
2201
#define SQLITE_CONFIG_LOOKASIDE           13  /* int int */
2202
#define SQLITE_CONFIG_PCACHE              14  /* no-op */
2203
#define SQLITE_CONFIG_GETPCACHE           15  /* no-op */
2204
#define SQLITE_CONFIG_LOG                 16  /* xFunc, void* */
2205
#define SQLITE_CONFIG_URI                 17  /* int */
2206
#define SQLITE_CONFIG_PCACHE2             18  /* sqlite3_pcache_methods2* */
2207
#define SQLITE_CONFIG_GETPCACHE2          19  /* sqlite3_pcache_methods2* */
2208
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
2209
#define SQLITE_CONFIG_SQLLOG              21  /* xSqllog, void* */
2210
#define SQLITE_CONFIG_MMAP_SIZE           22  /* sqlite3_int64, sqlite3_int64 */
2211
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
2212
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
2213
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
2214
#define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */
2215
#define SQLITE_CONFIG_SMALL_MALLOC        27  /* boolean */
2216
#define SQLITE_CONFIG_SORTERREF_SIZE      28  /* int nByte */
2217
#define SQLITE_CONFIG_MEMDB_MAXSIZE       29  /* sqlite3_int64 */
2218
#define SQLITE_CONFIG_ROWID_IN_VIEW       30  /* int* */
2219
2220
/*
2221
** CAPI3REF: Database Connection Configuration Options
2222
**
2223
** These constants are the available integer configuration options that
2224
** can be passed as the second parameter to the [sqlite3_db_config()] interface.
2225
**
2226
** The [sqlite3_db_config()] interface is a var-args functions.  It takes a
2227
** variable number of parameters, though always at least two.  The number of
2228
** parameters passed into sqlite3_db_config() depends on which of these
2229
** constants is given as the second parameter.  This documentation page
2230
** refers to parameters beyond the second as "arguments".  Thus, when this
2231
** page says "the N-th argument" it means "the N-th parameter past the
2232
** configuration option" or "the (N+2)-th parameter to sqlite3_db_config()".
2233
**
2234
** New configuration options may be added in future releases of SQLite.
2235
** Existing configuration options might be discontinued.  Applications
2236
** should check the return code from [sqlite3_db_config()] to make sure that
2237
** the call worked.  ^The [sqlite3_db_config()] interface will return a
2238
** non-zero [error code] if a discontinued or unsupported configuration option
2239
** is invoked.
2240
**
2241
** <dl>
2242
** [[SQLITE_DBCONFIG_LOOKASIDE]]
2243
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
2244
** <dd> The SQLITE_DBCONFIG_LOOKASIDE option is used to adjust the
2245
** configuration of the [lookaside memory allocator] within a database
2246
** connection.
2247
** The arguments to the SQLITE_DBCONFIG_LOOKASIDE option are <i>not</i>
2248
** in the [DBCONFIG arguments|usual format].
2249
** The SQLITE_DBCONFIG_LOOKASIDE option takes three arguments, not two,
2250
** so that a call to [sqlite3_db_config()] that uses SQLITE_DBCONFIG_LOOKASIDE
2251
** should have a total of five parameters.
2252
** <ol>
2253
** <li><p>The first argument ("buf") is a
2254
** pointer to a memory buffer to use for lookaside memory.
2255
** The first argument may be NULL in which case SQLite will allocate the
2256
** lookaside buffer itself using [sqlite3_malloc()].
2257
** <li><P>The second argument ("sz") is the
2258
** size of each lookaside buffer slot.  Lookaside is disabled if "sz"
2259
** is less than 8.  The "sz" argument should be a multiple of 8 less than
2260
** 65536.  If "sz" does not meet this constraint, it is reduced in size until
2261
** it does.
2262
** <li><p>The third argument ("cnt") is the number of slots. Lookaside is disabled
2263
** if "cnt"is less than 1.  The "cnt" value will be reduced, if necessary, so
2264
** that the product of "sz" and "cnt" does not exceed 2,147,418,112.  The "cnt"
2265
** parameter is usually chosen so that the product of "sz" and "cnt" is less
2266
** than 1,000,000.
2267
** </ol>
2268
** <p>If the "buf" argument is not NULL, then it must
2269
** point to a memory buffer with a size that is greater than
2270
** or equal to the product of "sz" and "cnt".
2271
** The buffer must be aligned to an 8-byte boundary.
2272
** The lookaside memory
2273
** configuration for a database connection can only be changed when that
2274
** connection is not currently using lookaside memory, or in other words
2275
** when the value returned by [SQLITE_DBSTATUS_LOOKASIDE_USED] is zero.
2276
** Any attempt to change the lookaside memory configuration when lookaside
2277
** memory is in use leaves the configuration unchanged and returns
2278
** [SQLITE_BUSY].
2279
** If the "buf" argument is NULL and an attempt
2280
** to allocate memory based on "sz" and "cnt" fails, then
2281
** lookaside is silently disabled.
2282
** <p>
2283
** The [SQLITE_CONFIG_LOOKASIDE] configuration option can be used to set the
2284
** default lookaside configuration at initialization.  The
2285
** [-DSQLITE_DEFAULT_LOOKASIDE] option can be used to set the default lookaside
2286
** configuration at compile-time.  Typical values for lookaside are 1200 for
2287
** "sz" and 40 to 100 for "cnt".
2288
** </dd>
2289
**
2290
** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
2291
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2292
** <dd> ^This option is used to enable or disable the enforcement of
2293
** [foreign key constraints].  This is the same setting that is
2294
** enabled or disabled by the [PRAGMA foreign_keys] statement.
2295
** The first argument is an integer which is 0 to disable FK enforcement,
2296
** positive to enable FK enforcement or negative to leave FK enforcement
2297
** unchanged.  The second parameter is a pointer to an integer into which
2298
** is written 0 or 1 to indicate whether FK enforcement is off or on
2299
** following this call.  The second parameter may be a NULL pointer, in
2300
** which case the FK enforcement setting is not reported back. </dd>
2301
**
2302
** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
2303
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2304
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2305
** There should be two additional arguments.
2306
** The first argument is an integer which is 0 to disable triggers,
2307
** positive to enable triggers or negative to leave the setting unchanged.
2308
** The second parameter is a pointer to an integer into which
2309
** is written 0 or 1 to indicate whether triggers are disabled or enabled
2310
** following this call.  The second parameter may be a NULL pointer, in
2311
** which case the trigger setting is not reported back.
2312
**
2313
** <p>Originally this option disabled all triggers.  ^(However, since
2314
** SQLite version 3.35.0, TEMP triggers are still allowed even if
2315
** this option is off.  So, in other words, this option now only disables
2316
** triggers in the main database schema or in the schemas of [ATTACH]-ed
2317
** databases.)^ </dd>
2318
**
2319
** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
2320
** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
2321
** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
2322
** There must be two additional arguments.
2323
** The first argument is an integer which is 0 to disable views,
2324
** positive to enable views or negative to leave the setting unchanged.
2325
** The second parameter is a pointer to an integer into which
2326
** is written 0 or 1 to indicate whether views are disabled or enabled
2327
** following this call.  The second parameter may be a NULL pointer, in
2328
** which case the view setting is not reported back.
2329
**
2330
** <p>Originally this option disabled all views.  ^(However, since
2331
** SQLite version 3.35.0, TEMP views are still allowed even if
2332
** this option is off.  So, in other words, this option now only disables
2333
** views in the main database schema or in the schemas of ATTACH-ed
2334
** databases.)^ </dd>
2335
**
2336
** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
2337
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
2338
** <dd> ^This option is used to enable or disable the
2339
** [fts3_tokenizer()] function which is part of the
2340
** [FTS3] full-text search engine extension.
2341
** There must be two additional arguments.
2342
** The first argument is an integer which is 0 to disable fts3_tokenizer() or
2343
** positive to enable fts3_tokenizer() or negative to leave the setting
2344
** unchanged.
2345
** The second parameter is a pointer to an integer into which
2346
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2347
** following this call.  The second parameter may be a NULL pointer, in
2348
** which case the new setting is not reported back. </dd>
2349
**
2350
** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
2351
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2352
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2353
** interface independently of the [load_extension()] SQL function.
2354
** The [sqlite3_enable_load_extension()] API enables or disables both the
2355
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2356
** There must be two additional arguments.
2357
** When the first argument to this interface is 1, then only the C-API is
2358
** enabled and the SQL function remains disabled.  If the first argument to
2359
** this interface is 0, then both the C-API and the SQL function are disabled.
2360
** If the first argument is -1, then no changes are made to state of either the
2361
** C-API or the SQL function.
2362
** The second parameter is a pointer to an integer into which
2363
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2364
** is disabled or enabled following this call.  The second parameter may
2365
** be a NULL pointer, in which case the new setting is not reported back.
2366
** </dd>
2367
**
2368
** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2369
** <dd> ^This option is used to change the name of the "main" database
2370
** schema.  This option does not follow the
2371
** [DBCONFIG arguments|usual SQLITE_DBCONFIG argument format].
2372
** This option takes exactly one additional argument so that the
2373
** [sqlite3_db_config()] call has a total of three parameters.  The
2374
** extra argument must be a pointer to a constant UTF8 string which
2375
** will become the new schema name in place of "main".  ^SQLite does
2376
** not make a copy of the new main schema name string, so the application
2377
** must ensure that the argument passed into SQLITE_DBCONFIG MAINDBNAME
2378
** is unchanged until after the database connection closes.
2379
** </dd>
2380
**
2381
** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
2382
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2383
** <dd> Usually, when a database in [WAL mode] is closed or detached from a
2384
** database handle, SQLite checks if if there are other connections to the
2385
** same database, and if there are no other database connection (if the
2386
** connection being closed is the last open connection to the database),
2387
** then SQLite performs a [checkpoint] before closing the connection and
2388
** deletes the WAL file.  The SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE option can
2389
** be used to override that behavior. The first argument passed to this
2390
** operation (the third parameter to [sqlite3_db_config()]) is an integer
2391
** which is positive to disable checkpoints-on-close, or zero (the default)
2392
** to enable them, and negative to leave the setting unchanged.
2393
** The second argument (the fourth parameter) is a pointer to an integer
2394
** into which is written 0 or 1 to indicate whether checkpoints-on-close
2395
** have been disabled - 0 if they are not disabled, 1 if they are.
2396
** </dd>
2397
**
2398
** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2399
** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2400
** the [query planner stability guarantee] (QPSG).  When the QPSG is active,
2401
** a single SQL query statement will always use the same algorithm regardless
2402
** of values of [bound parameters].)^ The QPSG disables some query optimizations
2403
** that look at the values of bound parameters, which can make some queries
2404
** slower.  But the QPSG has the advantage of more predictable behavior.  With
2405
** the QPSG active, SQLite will always use the same query plan in the field as
2406
** was used during testing in the lab.
2407
** The first argument to this setting is an integer which is 0 to disable
2408
** the QPSG, positive to enable QPSG, or negative to leave the setting
2409
** unchanged. The second parameter is a pointer to an integer into which
2410
** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2411
** following this call.
2412
** </dd>
2413
**
2414
** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
2415
** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
2416
** include output for any operations performed by trigger programs. This
2417
** option is used to set or clear (the default) a flag that governs this
2418
** behavior. The first parameter passed to this operation is an integer -
2419
** positive to enable output for trigger programs, or zero to disable it,
2420
** or negative to leave the setting unchanged.
2421
** The second parameter is a pointer to an integer into which is written
2422
** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
2423
** it is not disabled, 1 if it is.
2424
** </dd>
2425
**
2426
** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
2427
** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
2428
** [VACUUM] in order to reset a database back to an empty database
2429
** with no schema and no content. The following process works even for
2430
** a badly corrupted database file:
2431
** <ol>
2432
** <li> If the database connection is newly opened, make sure it has read the
2433
**      database schema by preparing then discarding some query against the
2434
**      database, or calling sqlite3_table_column_metadata(), ignoring any
2435
**      errors.  This step is only necessary if the application desires to keep
2436
**      the database in WAL mode after the reset if it was in WAL mode before
2437
**      the reset.
2438
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
2439
** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
2440
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
2441
** </ol>
2442
** Because resetting a database is destructive and irreversible, the
2443
** process requires the use of this obscure API and multiple steps to
2444
** help ensure that it does not happen by accident. Because this
2445
** feature must be capable of resetting corrupt databases, and
2446
** shutting down virtual tables may require access to that corrupt
2447
** storage, the library must abandon any installed virtual tables
2448
** without calling their xDestroy() methods.
2449
**
2450
** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
2451
** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
2452
** "defensive" flag for a database connection.  When the defensive
2453
** flag is enabled, language features that allow ordinary SQL to
2454
** deliberately corrupt the database file are disabled.  The disabled
2455
** features include but are not limited to the following:
2456
** <ul>
2457
** <li> The [PRAGMA writable_schema=ON] statement.
2458
** <li> The [PRAGMA journal_mode=OFF] statement.
2459
** <li> The [PRAGMA schema_version=N] statement.
2460
** <li> Writes to the [sqlite_dbpage] virtual table.
2461
** <li> Direct writes to [shadow tables].
2462
** </ul>
2463
** </dd>
2464
**
2465
** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
2466
** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
2467
** "writable_schema" flag. This has the same effect and is logically equivalent
2468
** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
2469
** The first argument to this setting is an integer which is 0 to disable
2470
** the writable_schema, positive to enable writable_schema, or negative to
2471
** leave the setting unchanged. The second parameter is a pointer to an
2472
** integer into which is written 0 or 1 to indicate whether the writable_schema
2473
** is enabled or disabled following this call.
2474
** </dd>
2475
**
2476
** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
2477
** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
2478
** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
2479
** the legacy behavior of the [ALTER TABLE RENAME] command such it
2480
** behaves as it did prior to [version 3.24.0] (2018-06-04).  See the
2481
** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
2482
** additional information. This feature can also be turned on and off
2483
** using the [PRAGMA legacy_alter_table] statement.
2484
** </dd>
2485
**
2486
** [[SQLITE_DBCONFIG_DQS_DML]]
2487
** <dt>SQLITE_DBCONFIG_DQS_DML</dt>
2488
** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
2489
** the legacy [double-quoted string literal] misfeature for DML statements
2490
** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
2491
** default value of this setting is determined by the [-DSQLITE_DQS]
2492
** compile-time option.
2493
** </dd>
2494
**
2495
** [[SQLITE_DBCONFIG_DQS_DDL]]
2496
** <dt>SQLITE_DBCONFIG_DQS_DDL</dt>
2497
** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
2498
** the legacy [double-quoted string literal] misfeature for DDL statements,
2499
** such as CREATE TABLE and CREATE INDEX. The
2500
** default value of this setting is determined by the [-DSQLITE_DQS]
2501
** compile-time option.
2502
** </dd>
2503
**
2504
** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
2505
** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt>
2506
** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
2507
** assume that database schemas are untainted by malicious content.
2508
** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
2509
** takes additional defensive steps to protect the application from harm
2510
** including:
2511
** <ul>
2512
** <li> Prohibit the use of SQL functions inside triggers, views,
2513
** CHECK constraints, DEFAULT clauses, expression indexes,
2514
** partial indexes, or generated columns
2515
** unless those functions are tagged with [SQLITE_INNOCUOUS].
2516
** <li> Prohibit the use of virtual tables inside of triggers or views
2517
** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
2518
** </ul>
2519
** This setting defaults to "on" for legacy compatibility, however
2520
** all applications are advised to turn it off if possible. This setting
2521
** can also be controlled using the [PRAGMA trusted_schema] statement.
2522
** </dd>
2523
**
2524
** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
2525
** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt>
2526
** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
2527
** the legacy file format flag.  When activated, this flag causes all newly
2528
** created database file to have a schema format version number (the 4-byte
2529
** integer found at offset 44 into the database header) of 1.  This in turn
2530
** means that the resulting database file will be readable and writable by
2531
** any SQLite version back to 3.0.0 ([dateof:3.0.0]).  Without this setting,
2532
** newly created databases are generally not understandable by SQLite versions
2533
** prior to 3.3.0 ([dateof:3.3.0]).  As these words are written, there
2534
** is now scarcely any need to generate database files that are compatible
2535
** all the way back to version 3.0.0, and so this setting is of little
2536
** practical use, but is provided so that SQLite can continue to claim the
2537
** ability to generate new database files that are compatible with  version
2538
** 3.0.0.
2539
** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
2540
** the [VACUUM] command will fail with an obscure error when attempting to
2541
** process a table with generated columns and a descending index.  This is
2542
** not considered a bug since SQLite versions 3.3.0 and earlier do not support
2543
** either generated columns or descending indexes.
2544
** </dd>
2545
**
2546
** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]]
2547
** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt>
2548
** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in
2549
** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears
2550
** a flag that enables collection of the sqlite3_stmt_scanstatus_v2()
2551
** statistics. For statistics to be collected, the flag must be set on
2552
** the database handle both when the SQL statement is prepared and when it
2553
** is stepped. The flag is set (collection of statistics is enabled)
2554
** by default. <p>This option takes two arguments: an integer and a pointer to
2555
** an integer..  The first argument is 1, 0, or -1 to enable, disable, or
2556
** leave unchanged the statement scanstatus option.  If the second argument
2557
** is not NULL, then the value of the statement scanstatus setting after
2558
** processing the first argument is written into the integer that the second
2559
** argument points to.
2560
** </dd>
2561
**
2562
** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]]
2563
** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt>
2564
** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order
2565
** in which tables and indexes are scanned so that the scans start at the end
2566
** and work toward the beginning rather than starting at the beginning and
2567
** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the
2568
** same as setting [PRAGMA reverse_unordered_selects]. <p>This option takes
2569
** two arguments which are an integer and a pointer to an integer.  The first
2570
** argument is 1, 0, or -1 to enable, disable, or leave unchanged the
2571
** reverse scan order flag, respectively.  If the second argument is not NULL,
2572
** then 0 or 1 is written into the integer that the second argument points to
2573
** depending on if the reverse scan order flag is set after processing the
2574
** first argument.
2575
** </dd>
2576
**
2577
** [[SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE]]
2578
** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE</dt>
2579
** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE option enables or disables
2580
** the ability of the [ATTACH DATABASE] SQL command to create a new database
2581
** file if the database filed named in the ATTACH command does not already
2582
** exist.  This ability of ATTACH to create a new database is enabled by
2583
** default.  Applications can disable or reenable the ability for ATTACH to
2584
** create new database files using this DBCONFIG option.<p>
2585
** This option takes two arguments which are an integer and a pointer
2586
** to an integer.  The first argument is 1, 0, or -1 to enable, disable, or
2587
** leave unchanged the attach-create flag, respectively.  If the second
2588
** argument is not NULL, then 0 or 1 is written into the integer that the
2589
** second argument points to depending on if the attach-create flag is set
2590
** after processing the first argument.
2591
** </dd>
2592
**
2593
** [[SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE]]
2594
** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE</dt>
2595
** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE option enables or disables the
2596
** ability of the [ATTACH DATABASE] SQL command to open a database for writing.
2597
** This capability is enabled by default.  Applications can disable or
2598
** reenable this capability using the current DBCONFIG option.  If the
2599
** the this capability is disabled, the [ATTACH] command will still work,
2600
** but the database will be opened read-only.  If this option is disabled,
2601
** then the ability to create a new database using [ATTACH] is also disabled,
2602
** regardless of the value of the [SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE]
2603
** option.<p>
2604
** This option takes two arguments which are an integer and a pointer
2605
** to an integer.  The first argument is 1, 0, or -1 to enable, disable, or
2606
** leave unchanged the ability to ATTACH another database for writing,
2607
** respectively.  If the second argument is not NULL, then 0 or 1 is written
2608
** into the integer to which the second argument points, depending on whether
2609
** the ability to ATTACH a read/write database is enabled or disabled
2610
** after processing the first argument.
2611
** </dd>
2612
**
2613
** [[SQLITE_DBCONFIG_ENABLE_COMMENTS]]
2614
** <dt>SQLITE_DBCONFIG_ENABLE_COMMENTS</dt>
2615
** <dd>The SQLITE_DBCONFIG_ENABLE_COMMENTS option enables or disables the
2616
** ability to include comments in SQL text.  Comments are enabled by default.
2617
** An application can disable or reenable comments in SQL text using this
2618
** DBCONFIG option.<p>
2619
** This option takes two arguments which are an integer and a pointer
2620
** to an integer.  The first argument is 1, 0, or -1 to enable, disable, or
2621
** leave unchanged the ability to use comments in SQL text,
2622
** respectively.  If the second argument is not NULL, then 0 or 1 is written
2623
** into the integer that the second argument points to depending on if
2624
** comments are allowed in SQL text after processing the first argument.
2625
** </dd>
2626
**
2627
** </dl>
2628
**
2629
** [[DBCONFIG arguments]] <h3>Arguments To SQLITE_DBCONFIG Options</h3>
2630
**
2631
** <p>Most of the SQLITE_DBCONFIG options take two arguments, so that the
2632
** overall call to [sqlite3_db_config()] has a total of four parameters.
2633
** The first argument (the third parameter to sqlite3_db_config()) is a integer.
2634
** The second argument is a pointer to an integer.  If the first argument is 1,
2635
** then the option becomes enabled.  If the first integer argument is 0, then the
2636
** option is disabled.  If the first argument is -1, then the option setting
2637
** is unchanged.  The second argument, the pointer to an integer, may be NULL.
2638
** If the second argument is not NULL, then a value of 0 or 1 is written into
2639
** the integer to which the second argument points, depending on whether the
2640
** setting is disabled or enabled after applying any changes specified by
2641
** the first argument.
2642
**
2643
** <p>While most SQLITE_DBCONFIG options use the argument format
2644
** described in the previous paragraph, the [SQLITE_DBCONFIG_MAINDBNAME]
2645
** and [SQLITE_DBCONFIG_LOOKASIDE] options are different.  See the
2646
** documentation of those exceptional options for details.
2647
*/
2648
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
2649
#define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
2650
#define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
2651
#define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
2652
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2653
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
2654
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */
2655
#define SQLITE_DBCONFIG_ENABLE_QPSG           1007 /* int int* */
2656
#define SQLITE_DBCONFIG_TRIGGER_EQP           1008 /* int int* */
2657
#define SQLITE_DBCONFIG_RESET_DATABASE        1009 /* int int* */
2658
#define SQLITE_DBCONFIG_DEFENSIVE             1010 /* int int* */
2659
#define SQLITE_DBCONFIG_WRITABLE_SCHEMA       1011 /* int int* */
2660
#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE    1012 /* int int* */
2661
#define SQLITE_DBCONFIG_DQS_DML               1013 /* int int* */
2662
#define SQLITE_DBCONFIG_DQS_DDL               1014 /* int int* */
2663
#define SQLITE_DBCONFIG_ENABLE_VIEW           1015 /* int int* */
2664
#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT    1016 /* int int* */
2665
#define SQLITE_DBCONFIG_TRUSTED_SCHEMA        1017 /* int int* */
2666
#define SQLITE_DBCONFIG_STMT_SCANSTATUS       1018 /* int int* */
2667
#define SQLITE_DBCONFIG_REVERSE_SCANORDER     1019 /* int int* */
2668
#define SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE  1020 /* int int* */
2669
#define SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE   1021 /* int int* */
2670
#define SQLITE_DBCONFIG_ENABLE_COMMENTS       1022 /* int int* */
2671
#define SQLITE_DBCONFIG_MAX                   1022 /* Largest DBCONFIG */
2672
2673
/*
2674
** CAPI3REF: Enable Or Disable Extended Result Codes
2675
** METHOD: sqlite3
2676
**
2677
** ^The sqlite3_extended_result_codes() routine enables or disables the
2678
** [extended result codes] feature of SQLite. ^The extended result
2679
** codes are disabled by default for historical compatibility.
2680
*/
2681
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2682
2683
/*
2684
** CAPI3REF: Last Insert Rowid
2685
** METHOD: sqlite3
2686
**
2687
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2688
** has a unique 64-bit signed
2689
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2690
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2691
** names are not also used by explicitly declared columns. ^If
2692
** the table has a column of type [INTEGER PRIMARY KEY] then that column
2693
** is another alias for the rowid.
2694
**
2695
** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2696
** the most recent successful [INSERT] into a rowid table or [virtual table]
2697
** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2698
** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
2699
** on the database connection D, then sqlite3_last_insert_rowid(D) returns
2700
** zero.
2701
**
2702
** As well as being set automatically as rows are inserted into database
2703
** tables, the value returned by this function may be set explicitly by
2704
** [sqlite3_set_last_insert_rowid()]
2705
**
2706
** Some virtual table implementations may INSERT rows into rowid tables as
2707
** part of committing a transaction (e.g. to flush data accumulated in memory
2708
** to disk). In this case subsequent calls to this function return the rowid
2709
** associated with these internal INSERT operations, which leads to
2710
** unintuitive results. Virtual table implementations that do write to rowid
2711
** tables in this way can avoid this problem by restoring the original
2712
** rowid value using [sqlite3_set_last_insert_rowid()] before returning
2713
** control to the user.
2714
**
2715
** ^(If an [INSERT] occurs within a trigger then this routine will
2716
** return the [rowid] of the inserted row as long as the trigger is
2717
** running. Once the trigger program ends, the value returned
2718
** by this routine reverts to what it was before the trigger was fired.)^
2719
**
2720
** ^An [INSERT] that fails due to a constraint violation is not a
2721
** successful [INSERT] and does not change the value returned by this
2722
** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2723
** and INSERT OR ABORT make no changes to the return value of this
2724
** routine when their insertion fails.  ^(When INSERT OR REPLACE
2725
** encounters a constraint violation, it does not fail.  The
2726
** INSERT continues to completion after deleting rows that caused
2727
** the constraint problem so INSERT OR REPLACE will always change
2728
** the return value of this interface.)^
2729
**
2730
** ^For the purposes of this routine, an [INSERT] is considered to
2731
** be successful even if it is subsequently rolled back.
2732
**
2733
** This function is accessible to SQL statements via the
2734
** [last_insert_rowid() SQL function].
2735
**
2736
** If a separate thread performs a new [INSERT] on the same
2737
** database connection while the [sqlite3_last_insert_rowid()]
2738
** function is running and thus changes the last insert [rowid],
2739
** then the value returned by [sqlite3_last_insert_rowid()] is
2740
** unpredictable and might not equal either the old or the new
2741
** last insert [rowid].
2742
*/
2743
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2744
2745
/*
2746
** CAPI3REF: Set the Last Insert Rowid value.
2747
** METHOD: sqlite3
2748
**
2749
** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2750
** set the value returned by calling sqlite3_last_insert_rowid(D) to R
2751
** without inserting a row into the database.
2752
*/
2753
SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2754
2755
/*
2756
** CAPI3REF: Count The Number Of Rows Modified
2757
** METHOD: sqlite3
2758
**
2759
** ^These functions return the number of rows modified, inserted or
2760
** deleted by the most recently completed INSERT, UPDATE or DELETE
2761
** statement on the database connection specified by the only parameter.
2762
** The two functions are identical except for the type of the return value
2763
** and that if the number of rows modified by the most recent INSERT, UPDATE,
2764
** or DELETE is greater than the maximum value supported by type "int", then
2765
** the return value of sqlite3_changes() is undefined. ^Executing any other
2766
** type of SQL statement does not modify the value returned by these functions.
2767
** For the purposes of this interface, a CREATE TABLE AS SELECT statement
2768
** does not count as an INSERT, UPDATE or DELETE statement and hence the rows
2769
** added to the new table by the CREATE TABLE AS SELECT statement are not
2770
** counted.
2771
**
2772
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2773
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2774
** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2775
**
2776
** Changes to a view that are intercepted by
2777
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2778
** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2779
** DELETE statement run on a view is always zero. Only changes made to real
2780
** tables are counted.
2781
**
2782
** Things are more complicated if the sqlite3_changes() function is
2783
** executed while a trigger program is running. This may happen if the
2784
** program uses the [changes() SQL function], or if some other callback
2785
** function invokes sqlite3_changes() directly. Essentially:
2786
**
2787
** <ul>
2788
**   <li> ^(Before entering a trigger program the value returned by
2789
**        sqlite3_changes() function is saved. After the trigger program
2790
**        has finished, the original value is restored.)^
2791
**
2792
**   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2793
**        statement sets the value returned by sqlite3_changes()
2794
**        upon completion as normal. Of course, this value will not include
2795
**        any changes performed by sub-triggers, as the sqlite3_changes()
2796
**        value will be saved and restored after each sub-trigger has run.)^
2797
** </ul>
2798
**
2799
** ^This means that if the changes() SQL function (or similar) is used
2800
** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2801
** returns the value as set when the calling statement began executing.
2802
** ^If it is used by the second or subsequent such statement within a trigger
2803
** program, the value returned reflects the number of rows modified by the
2804
** previous INSERT, UPDATE or DELETE statement within the same trigger.
2805
**
2806
** If a separate thread makes changes on the same database connection
2807
** while [sqlite3_changes()] is running then the value returned
2808
** is unpredictable and not meaningful.
2809
**
2810
** See also:
2811
** <ul>
2812
** <li> the [sqlite3_total_changes()] interface
2813
** <li> the [count_changes pragma]
2814
** <li> the [changes() SQL function]
2815
** <li> the [data_version pragma]
2816
** </ul>
2817
*/
2818
SQLITE_API int sqlite3_changes(sqlite3*);
2819
SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);
2820
2821
/*
2822
** CAPI3REF: Total Number Of Rows Modified
2823
** METHOD: sqlite3
2824
**
2825
** ^These functions return the total number of rows inserted, modified or
2826
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2827
** since the database connection was opened, including those executed as
2828
** part of trigger programs. The two functions are identical except for the
2829
** type of the return value and that if the number of rows modified by the
2830
** connection exceeds the maximum value supported by type "int", then
2831
** the return value of sqlite3_total_changes() is undefined. ^Executing
2832
** any other type of SQL statement does not affect the value returned by
2833
** sqlite3_total_changes().
2834
**
2835
** ^Changes made as part of [foreign key actions] are included in the
2836
** count, but those made as part of REPLACE constraint resolution are
2837
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2838
** are not counted.
2839
**
2840
** The [sqlite3_total_changes(D)] interface only reports the number
2841
** of rows that changed due to SQL statement run against database
2842
** connection D.  Any changes by other database connections are ignored.
2843
** To detect changes against a database file from other database
2844
** connections use the [PRAGMA data_version] command or the
2845
** [SQLITE_FCNTL_DATA_VERSION] [file control].
2846
**
2847
** If a separate thread makes changes on the same database connection
2848
** while [sqlite3_total_changes()] is running then the value
2849
** returned is unpredictable and not meaningful.
2850
**
2851
** See also:
2852
** <ul>
2853
** <li> the [sqlite3_changes()] interface
2854
** <li> the [count_changes pragma]
2855
** <li> the [changes() SQL function]
2856
** <li> the [data_version pragma]
2857
** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
2858
** </ul>
2859
*/
2860
SQLITE_API int sqlite3_total_changes(sqlite3*);
2861
SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*);
2862
2863
/*
2864
** CAPI3REF: Interrupt A Long-Running Query
2865
** METHOD: sqlite3
2866
**
2867
** ^This function causes any pending database operation to abort and
2868
** return at its earliest opportunity. This routine is typically
2869
** called in response to a user action such as pressing "Cancel"
2870
** or Ctrl-C where the user wants a long query operation to halt
2871
** immediately.
2872
**
2873
** ^It is safe to call this routine from a thread different from the
2874
** thread that is currently running the database operation.  But it
2875
** is not safe to call this routine with a [database connection] that
2876
** is closed or might close before sqlite3_interrupt() returns.
2877
**
2878
** ^If an SQL operation is very nearly finished at the time when
2879
** sqlite3_interrupt() is called, then it might not have an opportunity
2880
** to be interrupted and might continue to completion.
2881
**
2882
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2883
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2884
** that is inside an explicit transaction, then the entire transaction
2885
** will be rolled back automatically.
2886
**
2887
** ^The sqlite3_interrupt(D) call is in effect until all currently running
2888
** SQL statements on [database connection] D complete.  ^Any new SQL statements
2889
** that are started after the sqlite3_interrupt() call and before the
2890
** running statement count reaches zero are interrupted as if they had been
2891
** running prior to the sqlite3_interrupt() call.  ^New SQL statements
2892
** that are started after the running statement count reaches zero are
2893
** not effected by the sqlite3_interrupt().
2894
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2895
** SQL statements is a no-op and has no effect on SQL statements
2896
** that are started after the sqlite3_interrupt() call returns.
2897
**
2898
** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether
2899
** or not an interrupt is currently in effect for [database connection] D.
2900
** It returns 1 if an interrupt is currently in effect, or 0 otherwise.
2901
*/
2902
SQLITE_API void sqlite3_interrupt(sqlite3*);
2903
SQLITE_API int sqlite3_is_interrupted(sqlite3*);
2904
2905
/*
2906
** CAPI3REF: Determine If An SQL Statement Is Complete
2907
**
2908
** These routines are useful during command-line input to determine if the
2909
** currently entered text seems to form a complete SQL statement or
2910
** if additional input is needed before sending the text into
2911
** SQLite for parsing.  ^These routines return 1 if the input string
2912
** appears to be a complete SQL statement.  ^A statement is judged to be
2913
** complete if it ends with a semicolon token and is not a prefix of a
2914
** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
2915
** string literals or quoted identifier names or comments are not
2916
** independent tokens (they are part of the token in which they are
2917
** embedded) and thus do not count as a statement terminator.  ^Whitespace
2918
** and comments that follow the final semicolon are ignored.
2919
**
2920
** ^These routines return 0 if the statement is incomplete.  ^If a
2921
** memory allocation fails, then SQLITE_NOMEM is returned.
2922
**
2923
** ^These routines do not parse the SQL statements thus
2924
** will not detect syntactically incorrect SQL.
2925
**
2926
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2927
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2928
** automatically by sqlite3_complete16().  If that initialization fails,
2929
** then the return value from sqlite3_complete16() will be non-zero
2930
** regardless of whether or not the input SQL is complete.)^
2931
**
2932
** The input to [sqlite3_complete()] must be a zero-terminated
2933
** UTF-8 string.
2934
**
2935
** The input to [sqlite3_complete16()] must be a zero-terminated
2936
** UTF-16 string in native byte order.
2937
*/
2938
SQLITE_API int sqlite3_complete(const char *sql);
2939
SQLITE_API int sqlite3_complete16(const void *sql);
2940
2941
/*
2942
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2943
** KEYWORDS: {busy-handler callback} {busy handler}
2944
** METHOD: sqlite3
2945
**
2946
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2947
** that might be invoked with argument P whenever
2948
** an attempt is made to access a database table associated with
2949
** [database connection] D when another thread
2950
** or process has the table locked.
2951
** The sqlite3_busy_handler() interface is used to implement
2952
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
2953
**
2954
** ^If the busy callback is NULL, then [SQLITE_BUSY]
2955
** is returned immediately upon encountering the lock.  ^If the busy callback
2956
** is not NULL, then the callback might be invoked with two arguments.
2957
**
2958
** ^The first argument to the busy handler is a copy of the void* pointer which
2959
** is the third argument to sqlite3_busy_handler().  ^The second argument to
2960
** the busy handler callback is the number of times that the busy handler has
2961
** been invoked previously for the same locking event.  ^If the
2962
** busy callback returns 0, then no additional attempts are made to
2963
** access the database and [SQLITE_BUSY] is returned
2964
** to the application.
2965
** ^If the callback returns non-zero, then another attempt
2966
** is made to access the database and the cycle repeats.
2967
**
2968
** The presence of a busy handler does not guarantee that it will be invoked
2969
** when there is lock contention. ^If SQLite determines that invoking the busy
2970
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2971
** to the application instead of invoking the
2972
** busy handler.
2973
** Consider a scenario where one process is holding a read lock that
2974
** it is trying to promote to a reserved lock and
2975
** a second process is holding a reserved lock that it is trying
2976
** to promote to an exclusive lock.  The first process cannot proceed
2977
** because it is blocked by the second and the second process cannot
2978
** proceed because it is blocked by the first.  If both processes
2979
** invoke the busy handlers, neither will make any progress.  Therefore,
2980
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2981
** will induce the first process to release its read lock and allow
2982
** the second process to proceed.
2983
**
2984
** ^The default busy callback is NULL.
2985
**
2986
** ^(There can only be a single busy handler defined for each
2987
** [database connection].  Setting a new busy handler clears any
2988
** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
2989
** or evaluating [PRAGMA busy_timeout=N] will change the
2990
** busy handler and thus clear any previously set busy handler.
2991
**
2992
** The busy callback should not take any actions which modify the
2993
** database connection that invoked the busy handler.  In other words,
2994
** the busy handler is not reentrant.  Any such actions
2995
** result in undefined behavior.
2996
**
2997
** A busy handler must not close the database connection
2998
** or [prepared statement] that invoked the busy handler.
2999
*/
3000
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
3001
3002
/*
3003
** CAPI3REF: Set A Busy Timeout
3004
** METHOD: sqlite3
3005
**
3006
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
3007
** for a specified amount of time when a table is locked.  ^The handler
3008
** will sleep multiple times until at least "ms" milliseconds of sleeping
3009
** have accumulated.  ^After at least "ms" milliseconds of sleeping,
3010
** the handler returns 0 which causes [sqlite3_step()] to return
3011
** [SQLITE_BUSY].
3012
**
3013
** ^Calling this routine with an argument less than or equal to zero
3014
** turns off all busy handlers.
3015
**
3016
** ^(There can only be a single busy handler for a particular
3017
** [database connection] at any given moment.  If another busy handler
3018
** was defined  (using [sqlite3_busy_handler()]) prior to calling
3019
** this routine, that other busy handler is cleared.)^
3020
**
3021
** See also:  [PRAGMA busy_timeout]
3022
*/
3023
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
3024
3025
/*
3026
** CAPI3REF: Set the Setlk Timeout
3027
** METHOD: sqlite3
3028
**
3029
** This routine is only useful in SQLITE_ENABLE_SETLK_TIMEOUT builds. If
3030
** the VFS supports blocking locks, it sets the timeout in ms used by
3031
** eligible locks taken on wal mode databases by the specified database
3032
** handle. In non-SQLITE_ENABLE_SETLK_TIMEOUT builds, or if the VFS does
3033
** not support blocking locks, this function is a no-op.
3034
**
3035
** Passing 0 to this function disables blocking locks altogether. Passing
3036
** -1 to this function requests that the VFS blocks for a long time -
3037
** indefinitely if possible. The results of passing any other negative value
3038
** are undefined.
3039
**
3040
** Internally, each SQLite database handle store two timeout values - the
3041
** busy-timeout (used for rollback mode databases, or if the VFS does not
3042
** support blocking locks) and the setlk-timeout (used for blocking locks
3043
** on wal-mode databases). The sqlite3_busy_timeout() method sets both
3044
** values, this function sets only the setlk-timeout value. Therefore,
3045
** to configure separate busy-timeout and setlk-timeout values for a single
3046
** database handle, call sqlite3_busy_timeout() followed by this function.
3047
**
3048
** Whenever the number of connections to a wal mode database falls from
3049
** 1 to 0, the last connection takes an exclusive lock on the database,
3050
** then checkpoints and deletes the wal file. While it is doing this, any
3051
** new connection that tries to read from the database fails with an
3052
** SQLITE_BUSY error. Or, if the SQLITE_SETLK_BLOCK_ON_CONNECT flag is
3053
** passed to this API, the new connection blocks until the exclusive lock
3054
** has been released.
3055
*/
3056
SQLITE_API int sqlite3_setlk_timeout(sqlite3*, int ms, int flags);
3057
3058
/*
3059
** CAPI3REF: Flags for sqlite3_setlk_timeout()
3060
*/
3061
#define SQLITE_SETLK_BLOCK_ON_CONNECT 0x01
3062
3063
/*
3064
** CAPI3REF: Convenience Routines For Running Queries
3065
** METHOD: sqlite3
3066
**
3067
** This is a legacy interface that is preserved for backwards compatibility.
3068
** Use of this interface is not recommended.
3069
**
3070
** Definition: A <b>result table</b> is memory data structure created by the
3071
** [sqlite3_get_table()] interface.  A result table records the
3072
** complete query results from one or more queries.
3073
**
3074
** The table conceptually has a number of rows and columns.  But
3075
** these numbers are not part of the result table itself.  These
3076
** numbers are obtained separately.  Let N be the number of rows
3077
** and M be the number of columns.
3078
**
3079
** A result table is an array of pointers to zero-terminated UTF-8 strings.
3080
** There are (N+1)*M elements in the array.  The first M pointers point
3081
** to zero-terminated strings that  contain the names of the columns.
3082
** The remaining entries all point to query results.  NULL values result
3083
** in NULL pointers.  All other values are in their UTF-8 zero-terminated
3084
** string representation as returned by [sqlite3_column_text()].
3085
**
3086
** A result table might consist of one or more memory allocations.
3087
** It is not safe to pass a result table directly to [sqlite3_free()].
3088
** A result table should be deallocated using [sqlite3_free_table()].
3089
**
3090
** ^(As an example of the result table format, suppose a query result
3091
** is as follows:
3092
**
3093
** <blockquote><pre>
3094
**        Name        | Age
3095
**        -----------------------
3096
**        Alice       | 43
3097
**        Bob         | 28
3098
**        Cindy       | 21
3099
** </pre></blockquote>
3100
**
3101
** There are two columns (M==2) and three rows (N==3).  Thus the
3102
** result table has 8 entries.  Suppose the result table is stored
3103
** in an array named azResult.  Then azResult holds this content:
3104
**
3105
** <blockquote><pre>
3106
**        azResult&#91;0] = "Name";
3107
**        azResult&#91;1] = "Age";
3108
**        azResult&#91;2] = "Alice";
3109
**        azResult&#91;3] = "43";
3110
**        azResult&#91;4] = "Bob";
3111
**        azResult&#91;5] = "28";
3112
**        azResult&#91;6] = "Cindy";
3113
**        azResult&#91;7] = "21";
3114
** </pre></blockquote>)^
3115
**
3116
** ^The sqlite3_get_table() function evaluates one or more
3117
** semicolon-separated SQL statements in the zero-terminated UTF-8
3118
** string of its 2nd parameter and returns a result table to the
3119
** pointer given in its 3rd parameter.
3120
**
3121
** After the application has finished with the result from sqlite3_get_table(),
3122
** it must pass the result table pointer to sqlite3_free_table() in order to
3123
** release the memory that was malloced.  Because of the way the
3124
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
3125
** function must not try to call [sqlite3_free()] directly.  Only
3126
** [sqlite3_free_table()] is able to release the memory properly and safely.
3127
**
3128
** The sqlite3_get_table() interface is implemented as a wrapper around
3129
** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
3130
** to any internal data structures of SQLite.  It uses only the public
3131
** interface defined here.  As a consequence, errors that occur in the
3132
** wrapper layer outside of the internal [sqlite3_exec()] call are not
3133
** reflected in subsequent calls to [sqlite3_errcode()] or
3134
** [sqlite3_errmsg()].
3135
*/
3136
SQLITE_API int sqlite3_get_table(
3137
  sqlite3 *db,          /* An open database */
3138
  const char *zSql,     /* SQL to be evaluated */
3139
  char ***pazResult,    /* Results of the query */
3140
  int *pnRow,           /* Number of result rows written here */
3141
  int *pnColumn,        /* Number of result columns written here */
3142
  char **pzErrmsg       /* Error msg written here */
3143
);
3144
SQLITE_API void sqlite3_free_table(char **result);
3145
3146
/*
3147
** CAPI3REF: Formatted String Printing Functions
3148
**
3149
** These routines are work-alikes of the "printf()" family of functions
3150
** from the standard C library.
3151
** These routines understand most of the common formatting options from
3152
** the standard library printf()
3153
** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
3154
** See the [built-in printf()] documentation for details.
3155
**
3156
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
3157
** results into memory obtained from [sqlite3_malloc64()].
3158
** The strings returned by these two routines should be
3159
** released by [sqlite3_free()].  ^Both routines return a
3160
** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
3161
** memory to hold the resulting string.
3162
**
3163
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
3164
** the standard C library.  The result is written into the
3165
** buffer supplied as the second parameter whose size is given by
3166
** the first parameter. Note that the order of the
3167
** first two parameters is reversed from snprintf().)^  This is an
3168
** historical accident that cannot be fixed without breaking
3169
** backwards compatibility.  ^(Note also that sqlite3_snprintf()
3170
** returns a pointer to its buffer instead of the number of
3171
** characters actually written into the buffer.)^  We admit that
3172
** the number of characters written would be a more useful return
3173
** value but we cannot change the implementation of sqlite3_snprintf()
3174
** now without breaking compatibility.
3175
**
3176
** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
3177
** guarantees that the buffer is always zero-terminated.  ^The first
3178
** parameter "n" is the total size of the buffer, including space for
3179
** the zero terminator.  So the longest string that can be completely
3180
** written will be n-1 characters.
3181
**
3182
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
3183
**
3184
** See also:  [built-in printf()], [printf() SQL function]
3185
*/
3186
SQLITE_API char *sqlite3_mprintf(const char*,...);
3187
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
3188
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
3189
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
3190
3191
/*
3192
** CAPI3REF: Memory Allocation Subsystem
3193
**
3194
** The SQLite core uses these three routines for all of its own
3195
** internal memory allocation needs. "Core" in the previous sentence
3196
** does not include operating-system specific [VFS] implementation.  The
3197
** Windows VFS uses native malloc() and free() for some operations.
3198
**
3199
** ^The sqlite3_malloc() routine returns a pointer to a block
3200
** of memory at least N bytes in length, where N is the parameter.
3201
** ^If sqlite3_malloc() is unable to obtain sufficient free
3202
** memory, it returns a NULL pointer.  ^If the parameter N to
3203
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
3204
** a NULL pointer.
3205
**
3206
** ^The sqlite3_malloc64(N) routine works just like
3207
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
3208
** of a signed 32-bit integer.
3209
**
3210
** ^Calling sqlite3_free() with a pointer previously returned
3211
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
3212
** that it might be reused.  ^The sqlite3_free() routine is
3213
** a no-op if is called with a NULL pointer.  Passing a NULL pointer
3214
** to sqlite3_free() is harmless.  After being freed, memory
3215
** should neither be read nor written.  Even reading previously freed
3216
** memory might result in a segmentation fault or other severe error.
3217
** Memory corruption, a segmentation fault, or other severe error
3218
** might result if sqlite3_free() is called with a non-NULL pointer that
3219
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
3220
**
3221
** ^The sqlite3_realloc(X,N) interface attempts to resize a
3222
** prior memory allocation X to be at least N bytes.
3223
** ^If the X parameter to sqlite3_realloc(X,N)
3224
** is a NULL pointer then its behavior is identical to calling
3225
** sqlite3_malloc(N).
3226
** ^If the N parameter to sqlite3_realloc(X,N) is zero or
3227
** negative then the behavior is exactly the same as calling
3228
** sqlite3_free(X).
3229
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
3230
** of at least N bytes in size or NULL if insufficient memory is available.
3231
** ^If M is the size of the prior allocation, then min(N,M) bytes
3232
** of the prior allocation are copied into the beginning of buffer returned
3233
** by sqlite3_realloc(X,N) and the prior allocation is freed.
3234
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
3235
** prior allocation is not freed.
3236
**
3237
** ^The sqlite3_realloc64(X,N) interfaces works the same as
3238
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
3239
** of a 32-bit signed integer.
3240
**
3241
** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
3242
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
3243
** sqlite3_msize(X) returns the size of that memory allocation in bytes.
3244
** ^The value returned by sqlite3_msize(X) might be larger than the number
3245
** of bytes requested when X was allocated.  ^If X is a NULL pointer then
3246
** sqlite3_msize(X) returns zero.  If X points to something that is not
3247
** the beginning of memory allocation, or if it points to a formerly
3248
** valid memory allocation that has now been freed, then the behavior
3249
** of sqlite3_msize(X) is undefined and possibly harmful.
3250
**
3251
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
3252
** sqlite3_malloc64(), and sqlite3_realloc64()
3253
** is always aligned to at least an 8 byte boundary, or to a
3254
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
3255
** option is used.
3256
**
3257
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
3258
** must be either NULL or else pointers obtained from a prior
3259
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
3260
** not yet been released.
3261
**
3262
** The application must not read or write any part of
3263
** a block of memory after it has been released using
3264
** [sqlite3_free()] or [sqlite3_realloc()].
3265
*/
3266
SQLITE_API void *sqlite3_malloc(int);
3267
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
3268
SQLITE_API void *sqlite3_realloc(void*, int);
3269
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
3270
SQLITE_API void sqlite3_free(void*);
3271
SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
3272
3273
/*
3274
** CAPI3REF: Memory Allocator Statistics
3275
**
3276
** SQLite provides these two interfaces for reporting on the status
3277
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
3278
** routines, which form the built-in memory allocation subsystem.
3279
**
3280
** ^The [sqlite3_memory_used()] routine returns the number of bytes
3281
** of memory currently outstanding (malloced but not freed).
3282
** ^The [sqlite3_memory_highwater()] routine returns the maximum
3283
** value of [sqlite3_memory_used()] since the high-water mark
3284
** was last reset.  ^The values returned by [sqlite3_memory_used()] and
3285
** [sqlite3_memory_highwater()] include any overhead
3286
** added by SQLite in its implementation of [sqlite3_malloc()],
3287
** but not overhead added by the any underlying system library
3288
** routines that [sqlite3_malloc()] may call.
3289
**
3290
** ^The memory high-water mark is reset to the current value of
3291
** [sqlite3_memory_used()] if and only if the parameter to
3292
** [sqlite3_memory_highwater()] is true.  ^The value returned
3293
** by [sqlite3_memory_highwater(1)] is the high-water mark
3294
** prior to the reset.
3295
*/
3296
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
3297
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
3298
3299
/*
3300
** CAPI3REF: Pseudo-Random Number Generator
3301
**
3302
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
3303
** select random [ROWID | ROWIDs] when inserting new records into a table that
3304
** already uses the largest possible [ROWID].  The PRNG is also used for
3305
** the built-in random() and randomblob() SQL functions.  This interface allows
3306
** applications to access the same PRNG for other purposes.
3307
**
3308
** ^A call to this routine stores N bytes of randomness into buffer P.
3309
** ^The P parameter can be a NULL pointer.
3310
**
3311
** ^If this routine has not been previously called or if the previous
3312
** call had N less than one or a NULL pointer for P, then the PRNG is
3313
** seeded using randomness obtained from the xRandomness method of
3314
** the default [sqlite3_vfs] object.
3315
** ^If the previous call to this routine had an N of 1 or more and a
3316
** non-NULL P then the pseudo-randomness is generated
3317
** internally and without recourse to the [sqlite3_vfs] xRandomness
3318
** method.
3319
*/
3320
SQLITE_API void sqlite3_randomness(int N, void *P);
3321
3322
/*
3323
** CAPI3REF: Compile-Time Authorization Callbacks
3324
** METHOD: sqlite3
3325
** KEYWORDS: {authorizer callback}
3326
**
3327
** ^This routine registers an authorizer callback with a particular
3328
** [database connection], supplied in the first argument.
3329
** ^The authorizer callback is invoked as SQL statements are being compiled
3330
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
3331
** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
3332
** and [sqlite3_prepare16_v3()].  ^At various
3333
** points during the compilation process, as logic is being created
3334
** to perform various actions, the authorizer callback is invoked to
3335
** see if those actions are allowed.  ^The authorizer callback should
3336
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
3337
** specific action but allow the SQL statement to continue to be
3338
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
3339
** rejected with an error.  ^If the authorizer callback returns
3340
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
3341
** then the [sqlite3_prepare_v2()] or equivalent call that triggered
3342
** the authorizer will fail with an error message.
3343
**
3344
** When the callback returns [SQLITE_OK], that means the operation
3345
** requested is ok.  ^When the callback returns [SQLITE_DENY], the
3346
** [sqlite3_prepare_v2()] or equivalent call that triggered the
3347
** authorizer will fail with an error message explaining that
3348
** access is denied.
3349
**
3350
** ^The first parameter to the authorizer callback is a copy of the third
3351
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
3352
** to the callback is an integer [SQLITE_COPY | action code] that specifies
3353
** the particular action to be authorized. ^The third through sixth parameters
3354
** to the callback are either NULL pointers or zero-terminated strings
3355
** that contain additional details about the action to be authorized.
3356
** Applications must always be prepared to encounter a NULL pointer in any
3357
** of the third through the sixth parameters of the authorization callback.
3358
**
3359
** ^If the action code is [SQLITE_READ]
3360
** and the callback returns [SQLITE_IGNORE] then the
3361
** [prepared statement] statement is constructed to substitute
3362
** a NULL value in place of the table column that would have
3363
** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
3364
** return can be used to deny an untrusted user access to individual
3365
** columns of a table.
3366
** ^When a table is referenced by a [SELECT] but no column values are
3367
** extracted from that table (for example in a query like
3368
** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
3369
** is invoked once for that table with a column name that is an empty string.
3370
** ^If the action code is [SQLITE_DELETE] and the callback returns
3371
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
3372
** [truncate optimization] is disabled and all rows are deleted individually.
3373
**
3374
** An authorizer is used when [sqlite3_prepare | preparing]
3375
** SQL statements from an untrusted source, to ensure that the SQL statements
3376
** do not try to access data they are not allowed to see, or that they do not
3377
** try to execute malicious statements that damage the database.  For
3378
** example, an application may allow a user to enter arbitrary
3379
** SQL queries for evaluation by a database.  But the application does
3380
** not want the user to be able to make arbitrary changes to the
3381
** database.  An authorizer could then be put in place while the
3382
** user-entered SQL is being [sqlite3_prepare | prepared] that
3383
** disallows everything except [SELECT] statements.
3384
**
3385
** Applications that need to process SQL from untrusted sources
3386
** might also consider lowering resource limits using [sqlite3_limit()]
3387
** and limiting database size using the [max_page_count] [PRAGMA]
3388
** in addition to using an authorizer.
3389
**
3390
** ^(Only a single authorizer can be in place on a database connection
3391
** at a time.  Each call to sqlite3_set_authorizer overrides the
3392
** previous call.)^  ^Disable the authorizer by installing a NULL callback.
3393
** The authorizer is disabled by default.
3394
**
3395
** The authorizer callback must not do anything that will modify
3396
** the database connection that invoked the authorizer callback.
3397
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3398
** database connections for the meaning of "modify" in this paragraph.
3399
**
3400
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
3401
** statement might be re-prepared during [sqlite3_step()] due to a
3402
** schema change.  Hence, the application should ensure that the
3403
** correct authorizer callback remains in place during the [sqlite3_step()].
3404
**
3405
** ^Note that the authorizer callback is invoked only during
3406
** [sqlite3_prepare()] or its variants.  Authorization is not
3407
** performed during statement evaluation in [sqlite3_step()], unless
3408
** as stated in the previous paragraph, sqlite3_step() invokes
3409
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
3410
*/
3411
SQLITE_API int sqlite3_set_authorizer(
3412
  sqlite3*,
3413
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
3414
  void *pUserData
3415
);
3416
3417
/*
3418
** CAPI3REF: Authorizer Return Codes
3419
**
3420
** The [sqlite3_set_authorizer | authorizer callback function] must
3421
** return either [SQLITE_OK] or one of these two constants in order
3422
** to signal SQLite whether or not the action is permitted.  See the
3423
** [sqlite3_set_authorizer | authorizer documentation] for additional
3424
** information.
3425
**
3426
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
3427
** returned from the [sqlite3_vtab_on_conflict()] interface.
3428
*/
3429
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
3430
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
3431
3432
/*
3433
** CAPI3REF: Authorizer Action Codes
3434
**
3435
** The [sqlite3_set_authorizer()] interface registers a callback function
3436
** that is invoked to authorize certain SQL statement actions.  The
3437
** second parameter to the callback is an integer code that specifies
3438
** what action is being authorized.  These are the integer action codes that
3439
** the authorizer callback may be passed.
3440
**
3441
** These action code values signify what kind of operation is to be
3442
** authorized.  The 3rd and 4th parameters to the authorization
3443
** callback function will be parameters or NULL depending on which of these
3444
** codes is used as the second parameter.  ^(The 5th parameter to the
3445
** authorizer callback is the name of the database ("main", "temp",
3446
** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
3447
** is the name of the inner-most trigger or view that is responsible for
3448
** the access attempt or NULL if this access attempt is directly from
3449
** top-level SQL code.
3450
*/
3451
/******************************************* 3rd ************ 4th ***********/
3452
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
3453
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
3454
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
3455
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
3456
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
3457
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
3458
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
3459
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
3460
#define SQLITE_DELETE                9   /* Table Name      NULL            */
3461
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
3462
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
3463
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
3464
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
3465
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
3466
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
3467
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
3468
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
3469
#define SQLITE_INSERT               18   /* Table Name      NULL            */
3470
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
3471
#define SQLITE_READ                 20   /* Table Name      Column Name     */
3472
#define SQLITE_SELECT               21   /* NULL            NULL            */
3473
#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
3474
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
3475
#define SQLITE_ATTACH               24   /* Filename        NULL            */
3476
#define SQLITE_DETACH               25   /* Database Name   NULL            */
3477
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
3478
#define SQLITE_REINDEX              27   /* Index Name      NULL            */
3479
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
3480
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
3481
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
3482
#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
3483
#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
3484
#define SQLITE_COPY                  0   /* No longer used */
3485
#define SQLITE_RECURSIVE            33   /* NULL            NULL            */
3486
3487
/*
3488
** CAPI3REF: Deprecated Tracing And Profiling Functions
3489
** DEPRECATED
3490
**
3491
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
3492
** instead of the routines described here.
3493
**
3494
** These routines register callback functions that can be used for
3495
** tracing and profiling the execution of SQL statements.
3496
**
3497
** ^The callback function registered by sqlite3_trace() is invoked at
3498
** various times when an SQL statement is being run by [sqlite3_step()].
3499
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
3500
** SQL statement text as the statement first begins executing.
3501
** ^(Additional sqlite3_trace() callbacks might occur
3502
** as each triggered subprogram is entered.  The callbacks for triggers
3503
** contain a UTF-8 SQL comment that identifies the trigger.)^
3504
**
3505
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
3506
** the length of [bound parameter] expansion in the output of sqlite3_trace().
3507
**
3508
** ^The callback function registered by sqlite3_profile() is invoked
3509
** as each SQL statement finishes.  ^The profile callback contains
3510
** the original statement text and an estimate of wall-clock time
3511
** of how long that statement took to run.  ^The profile callback
3512
** time is in units of nanoseconds, however the current implementation
3513
** is only capable of millisecond resolution so the six least significant
3514
** digits in the time are meaningless.  Future versions of SQLite
3515
** might provide greater resolution on the profiler callback.  Invoking
3516
** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
3517
** profile callback.
3518
*/
3519
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
3520
   void(*xTrace)(void*,const char*), void*);
3521
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
3522
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
3523
3524
/*
3525
** CAPI3REF: SQL Trace Event Codes
3526
** KEYWORDS: SQLITE_TRACE
3527
**
3528
** These constants identify classes of events that can be monitored
3529
** using the [sqlite3_trace_v2()] tracing logic.  The M argument
3530
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
3531
** the following constants.  ^The first argument to the trace callback
3532
** is one of the following constants.
3533
**
3534
** New tracing constants may be added in future releases.
3535
**
3536
** ^A trace callback has four arguments: xCallback(T,C,P,X).
3537
** ^The T argument is one of the integer type codes above.
3538
** ^The C argument is a copy of the context pointer passed in as the
3539
** fourth argument to [sqlite3_trace_v2()].
3540
** The P and X arguments are pointers whose meanings depend on T.
3541
**
3542
** <dl>
3543
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
3544
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
3545
** first begins running and possibly at other times during the
3546
** execution of the prepared statement, such as at the start of each
3547
** trigger subprogram. ^The P argument is a pointer to the
3548
** [prepared statement]. ^The X argument is a pointer to a string which
3549
** is the unexpanded SQL text of the prepared statement or an SQL comment
3550
** that indicates the invocation of a trigger.  ^The callback can compute
3551
** the same text that would have been returned by the legacy [sqlite3_trace()]
3552
** interface by using the X argument when X begins with "--" and invoking
3553
** [sqlite3_expanded_sql(P)] otherwise.
3554
**
3555
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
3556
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
3557
** information as is provided by the [sqlite3_profile()] callback.
3558
** ^The P argument is a pointer to the [prepared statement] and the
3559
** X argument points to a 64-bit integer which is approximately
3560
** the number of nanoseconds that the prepared statement took to run.
3561
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
3562
**
3563
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
3564
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
3565
** statement generates a single row of result.
3566
** ^The P argument is a pointer to the [prepared statement] and the
3567
** X argument is unused.
3568
**
3569
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
3570
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
3571
** connection closes.
3572
** ^The P argument is a pointer to the [database connection] object
3573
** and the X argument is unused.
3574
** </dl>
3575
*/
3576
#define SQLITE_TRACE_STMT       0x01
3577
#define SQLITE_TRACE_PROFILE    0x02
3578
#define SQLITE_TRACE_ROW        0x04
3579
#define SQLITE_TRACE_CLOSE      0x08
3580
3581
/*
3582
** CAPI3REF: SQL Trace Hook
3583
** METHOD: sqlite3
3584
**
3585
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
3586
** function X against [database connection] D, using property mask M
3587
** and context pointer P.  ^If the X callback is
3588
** NULL or if the M mask is zero, then tracing is disabled.  The
3589
** M argument should be the bitwise OR-ed combination of
3590
** zero or more [SQLITE_TRACE] constants.
3591
**
3592
** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P)
3593
** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or
3594
** sqlite3_trace_v2(D,M,X,P) for the [database connection] D.  Each
3595
** database connection may have at most one trace callback.
3596
**
3597
** ^The X callback is invoked whenever any of the events identified by
3598
** mask M occur.  ^The integer return value from the callback is currently
3599
** ignored, though this may change in future releases.  Callback
3600
** implementations should return zero to ensure future compatibility.
3601
**
3602
** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
3603
** ^The T argument is one of the [SQLITE_TRACE]
3604
** constants to indicate why the callback was invoked.
3605
** ^The C argument is a copy of the context pointer.
3606
** The P and X arguments are pointers whose meanings depend on T.
3607
**
3608
** The sqlite3_trace_v2() interface is intended to replace the legacy
3609
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3610
** are deprecated.
3611
*/
3612
SQLITE_API int sqlite3_trace_v2(
3613
  sqlite3*,
3614
  unsigned uMask,
3615
  int(*xCallback)(unsigned,void*,void*,void*),
3616
  void *pCtx
3617
);
3618
3619
/*
3620
** CAPI3REF: Query Progress Callbacks
3621
** METHOD: sqlite3
3622
**
3623
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3624
** function X to be invoked periodically during long running calls to
3625
** [sqlite3_step()] and [sqlite3_prepare()] and similar for
3626
** database connection D.  An example use for this
3627
** interface is to keep a GUI updated during a large query.
3628
**
3629
** ^The parameter P is passed through as the only parameter to the
3630
** callback function X.  ^The parameter N is the approximate number of
3631
** [virtual machine instructions] that are evaluated between successive
3632
** invocations of the callback X.  ^If N is less than one then the progress
3633
** handler is disabled.
3634
**
3635
** ^Only a single progress handler may be defined at one time per
3636
** [database connection]; setting a new progress handler cancels the
3637
** old one.  ^Setting parameter X to NULL disables the progress handler.
3638
** ^The progress handler is also disabled by setting N to a value less
3639
** than 1.
3640
**
3641
** ^If the progress callback returns non-zero, the operation is
3642
** interrupted.  This feature can be used to implement a
3643
** "Cancel" button on a GUI progress dialog box.
3644
**
3645
** The progress handler callback must not do anything that will modify
3646
** the database connection that invoked the progress handler.
3647
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3648
** database connections for the meaning of "modify" in this paragraph.
3649
**
3650
** The progress handler callback would originally only be invoked from the
3651
** bytecode engine.  It still might be invoked during [sqlite3_prepare()]
3652
** and similar because those routines might force a reparse of the schema
3653
** which involves running the bytecode engine.  However, beginning with
3654
** SQLite version 3.41.0, the progress handler callback might also be
3655
** invoked directly from [sqlite3_prepare()] while analyzing and generating
3656
** code for complex queries.
3657
*/
3658
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3659
3660
/*
3661
** CAPI3REF: Opening A New Database Connection
3662
** CONSTRUCTOR: sqlite3
3663
**
3664
** ^These routines open an SQLite database file as specified by the
3665
** filename argument. ^The filename argument is interpreted as UTF-8 for
3666
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3667
** order for sqlite3_open16(). ^(A [database connection] handle is usually
3668
** returned in *ppDb, even if an error occurs.  The only exception is that
3669
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3670
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3671
** object.)^ ^(If the database is opened (and/or created) successfully, then
3672
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
3673
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3674
** an English language description of the error following a failure of any
3675
** of the sqlite3_open() routines.
3676
**
3677
** ^The default encoding will be UTF-8 for databases created using
3678
** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
3679
** created using sqlite3_open16() will be UTF-16 in the native byte order.
3680
**
3681
** Whether or not an error occurs when it is opened, resources
3682
** associated with the [database connection] handle should be released by
3683
** passing it to [sqlite3_close()] when it is no longer required.
3684
**
3685
** The sqlite3_open_v2() interface works like sqlite3_open()
3686
** except that it accepts two additional parameters for additional control
3687
** over the new database connection.  ^(The flags parameter to
3688
** sqlite3_open_v2() must include, at a minimum, one of the following
3689
** three flag combinations:)^
3690
**
3691
** <dl>
3692
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3693
** <dd>The database is opened in read-only mode.  If the database does
3694
** not already exist, an error is returned.</dd>)^
3695
**
3696
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3697
** <dd>The database is opened for reading and writing if possible, or
3698
** reading only if the file is write protected by the operating
3699
** system.  In either case the database must already exist, otherwise
3700
** an error is returned.  For historical reasons, if opening in
3701
** read-write mode fails due to OS-level permissions, an attempt is
3702
** made to open it in read-only mode. [sqlite3_db_readonly()] can be
3703
** used to determine whether the database is actually
3704
** read-write.</dd>)^
3705
**
3706
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3707
** <dd>The database is opened for reading and writing, and is created if
3708
** it does not already exist. This is the behavior that is always used for
3709
** sqlite3_open() and sqlite3_open16().</dd>)^
3710
** </dl>
3711
**
3712
** In addition to the required flags, the following optional flags are
3713
** also supported:
3714
**
3715
** <dl>
3716
** ^(<dt>[SQLITE_OPEN_URI]</dt>
3717
** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
3718
**
3719
** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
3720
** <dd>The database will be opened as an in-memory database.  The database
3721
** is named by the "filename" argument for the purposes of cache-sharing,
3722
** if shared cache mode is enabled, but the "filename" is otherwise ignored.
3723
** </dd>)^
3724
**
3725
** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
3726
** <dd>The new database connection will use the "multi-thread"
3727
** [threading mode].)^  This means that separate threads are allowed
3728
** to use SQLite at the same time, as long as each thread is using
3729
** a different [database connection].
3730
**
3731
** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
3732
** <dd>The new database connection will use the "serialized"
3733
** [threading mode].)^  This means the multiple threads can safely
3734
** attempt to use the same database connection at the same time.
3735
** (Mutexes will block any actual concurrency, but in this mode
3736
** there is no harm in trying.)
3737
**
3738
** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
3739
** <dd>The database is opened [shared cache] enabled, overriding
3740
** the default shared cache setting provided by
3741
** [sqlite3_enable_shared_cache()].)^
3742
** The [use of shared cache mode is discouraged] and hence shared cache
3743
** capabilities may be omitted from many builds of SQLite.  In such cases,
3744
** this option is a no-op.
3745
**
3746
** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
3747
** <dd>The database is opened [shared cache] disabled, overriding
3748
** the default shared cache setting provided by
3749
** [sqlite3_enable_shared_cache()].)^
3750
**
3751
** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
3752
** <dd>The database connection comes up in "extended result code mode".
3753
** In other words, the database behaves as if
3754
** [sqlite3_extended_result_codes(db,1)] were called on the database
3755
** connection as soon as the connection is created. In addition to setting
3756
** the extended result code mode, this flag also causes [sqlite3_open_v2()]
3757
** to return an extended result code.</dd>
3758
**
3759
** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
3760
** <dd>The database filename is not allowed to contain a symbolic link</dd>
3761
** </dl>)^
3762
**
3763
** If the 3rd parameter to sqlite3_open_v2() is not one of the
3764
** required combinations shown above optionally combined with other
3765
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3766
** then the behavior is undefined.  Historic versions of SQLite
3767
** have silently ignored surplus bits in the flags parameter to
3768
** sqlite3_open_v2(), however that behavior might not be carried through
3769
** into future versions of SQLite and so applications should not rely
3770
** upon it.  Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op
3771
** for sqlite3_open_v2().  The SQLITE_OPEN_EXCLUSIVE does *not* cause
3772
** the open to fail if the database already exists.  The SQLITE_OPEN_EXCLUSIVE
3773
** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not
3774
** by sqlite3_open_v2().
3775
**
3776
** ^The fourth parameter to sqlite3_open_v2() is the name of the
3777
** [sqlite3_vfs] object that defines the operating system interface that
3778
** the new database connection should use.  ^If the fourth parameter is
3779
** a NULL pointer then the default [sqlite3_vfs] object is used.
3780
**
3781
** ^If the filename is ":memory:", then a private, temporary in-memory database
3782
** is created for the connection.  ^This in-memory database will vanish when
3783
** the database connection is closed.  Future versions of SQLite might
3784
** make use of additional special filenames that begin with the ":" character.
3785
** It is recommended that when a database filename actually does begin with
3786
** a ":" character you should prefix the filename with a pathname such as
3787
** "./" to avoid ambiguity.
3788
**
3789
** ^If the filename is an empty string, then a private, temporary
3790
** on-disk database will be created.  ^This private database will be
3791
** automatically deleted as soon as the database connection is closed.
3792
**
3793
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3794
**
3795
** ^If [URI filename] interpretation is enabled, and the filename argument
3796
** begins with "file:", then the filename is interpreted as a URI. ^URI
3797
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3798
** set in the third argument to sqlite3_open_v2(), or if it has
3799
** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3800
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3801
** URI filename interpretation is turned off
3802
** by default, but future releases of SQLite might enable URI filename
3803
** interpretation by default.  See "[URI filenames]" for additional
3804
** information.
3805
**
3806
** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3807
** authority, then it must be either an empty string or the string
3808
** "localhost". ^If the authority is not an empty string or "localhost", an
3809
** error is returned to the caller. ^The fragment component of a URI, if
3810
** present, is ignored.
3811
**
3812
** ^SQLite uses the path component of the URI as the name of the disk file
3813
** which contains the database. ^If the path begins with a '/' character,
3814
** then it is interpreted as an absolute path. ^If the path does not begin
3815
** with a '/' (meaning that the authority section is omitted from the URI)
3816
** then the path is interpreted as a relative path.
3817
** ^(On windows, the first component of an absolute path
3818
** is a drive specification (e.g. "C:").)^
3819
**
3820
** [[core URI query parameters]]
3821
** The query component of a URI may contain parameters that are interpreted
3822
** either by SQLite itself, or by a [VFS | custom VFS implementation].
3823
** SQLite and its built-in [VFSes] interpret the
3824
** following query parameters:
3825
**
3826
** <ul>
3827
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3828
**     a VFS object that provides the operating system interface that should
3829
**     be used to access the database file on disk. ^If this option is set to
3830
**     an empty string the default VFS object is used. ^Specifying an unknown
3831
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3832
**     present, then the VFS specified by the option takes precedence over
3833
**     the value passed as the fourth parameter to sqlite3_open_v2().
3834
**
3835
**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3836
**     "rwc", or "memory". Attempting to set it to any other value is
3837
**     an error)^.
3838
**     ^If "ro" is specified, then the database is opened for read-only
3839
**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3840
**     third argument to sqlite3_open_v2(). ^If the mode option is set to
3841
**     "rw", then the database is opened for read-write (but not create)
3842
**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3843
**     been set. ^Value "rwc" is equivalent to setting both
3844
**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
3845
**     set to "memory" then a pure [in-memory database] that never reads
3846
**     or writes from disk is used. ^It is an error to specify a value for
3847
**     the mode parameter that is less restrictive than that specified by
3848
**     the flags passed in the third parameter to sqlite3_open_v2().
3849
**
3850
**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3851
**     "private". ^Setting it to "shared" is equivalent to setting the
3852
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3853
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3854
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3855
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3856
**     a URI filename, its value overrides any behavior requested by setting
3857
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3858
**
3859
**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3860
**     [powersafe overwrite] property does or does not apply to the
3861
**     storage media on which the database file resides.
3862
**
3863
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3864
**     which if set disables file locking in rollback journal modes.  This
3865
**     is useful for accessing a database on a filesystem that does not
3866
**     support locking.  Caution:  Database corruption might result if two
3867
**     or more processes write to the same database and any one of those
3868
**     processes uses nolock=1.
3869
**
3870
**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3871
**     parameter that indicates that the database file is stored on
3872
**     read-only media.  ^When immutable is set, SQLite assumes that the
3873
**     database file cannot be changed, even by a process with higher
3874
**     privilege, and so the database is opened read-only and all locking
3875
**     and change detection is disabled.  Caution: Setting the immutable
3876
**     property on a database file that does in fact change can result
3877
**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
3878
**     See also: [SQLITE_IOCAP_IMMUTABLE].
3879
**
3880
** </ul>
3881
**
3882
** ^Specifying an unknown parameter in the query component of a URI is not an
3883
** error.  Future versions of SQLite might understand additional query
3884
** parameters.  See "[query parameters with special meaning to SQLite]" for
3885
** additional information.
3886
**
3887
** [[URI filename examples]] <h3>URI filename examples</h3>
3888
**
3889
** <table border="1" align=center cellpadding=5>
3890
** <tr><th> URI filenames <th> Results
3891
** <tr><td> file:data.db <td>
3892
**          Open the file "data.db" in the current directory.
3893
** <tr><td> file:/home/fred/data.db<br>
3894
**          file:///home/fred/data.db <br>
3895
**          file://localhost/home/fred/data.db <br> <td>
3896
**          Open the database file "/home/fred/data.db".
3897
** <tr><td> file://darkstar/home/fred/data.db <td>
3898
**          An error. "darkstar" is not a recognized authority.
3899
** <tr><td style="white-space:nowrap">
3900
**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3901
**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
3902
**          C:. Note that the %20 escaping in this example is not strictly
3903
**          necessary - space characters can be used literally
3904
**          in URI filenames.
3905
** <tr><td> file:data.db?mode=ro&cache=private <td>
3906
**          Open file "data.db" in the current directory for read-only access.
3907
**          Regardless of whether or not shared-cache mode is enabled by
3908
**          default, use a private cache.
3909
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3910
**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3911
**          that uses dot-files in place of posix advisory locking.
3912
** <tr><td> file:data.db?mode=readonly <td>
3913
**          An error. "readonly" is not a valid option for the "mode" parameter.
3914
**          Use "ro" instead:  "file:data.db?mode=ro".
3915
** </table>
3916
**
3917
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3918
** query components of a URI. A hexadecimal escape sequence consists of a
3919
** percent sign - "%" - followed by exactly two hexadecimal digits
3920
** specifying an octet value. ^Before the path or query components of a
3921
** URI filename are interpreted, they are encoded using UTF-8 and all
3922
** hexadecimal escape sequences replaced by a single byte containing the
3923
** corresponding octet. If this process generates an invalid UTF-8 encoding,
3924
** the results are undefined.
3925
**
3926
** <b>Note to Windows users:</b>  The encoding used for the filename argument
3927
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3928
** codepage is currently defined.  Filenames containing international
3929
** characters must be converted to UTF-8 prior to passing them into
3930
** sqlite3_open() or sqlite3_open_v2().
3931
**
3932
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
3933
** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
3934
** features that require the use of temporary files may fail.
3935
**
3936
** See also: [sqlite3_temp_directory]
3937
*/
3938
SQLITE_API int sqlite3_open(
3939
  const char *filename,   /* Database filename (UTF-8) */
3940
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3941
);
3942
SQLITE_API int sqlite3_open16(
3943
  const void *filename,   /* Database filename (UTF-16) */
3944
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3945
);
3946
SQLITE_API int sqlite3_open_v2(
3947
  const char *filename,   /* Database filename (UTF-8) */
3948
  sqlite3 **ppDb,         /* OUT: SQLite db handle */
3949
  int flags,              /* Flags */
3950
  const char *zVfs        /* Name of VFS module to use */
3951
);
3952
3953
/*
3954
** CAPI3REF: Obtain Values For URI Parameters
3955
**
3956
** These are utility routines, useful to [VFS|custom VFS implementations],
3957
** that check if a database file was a URI that contained a specific query
3958
** parameter, and if so obtains the value of that query parameter.
3959
**
3960
** The first parameter to these interfaces (hereafter referred to
3961
** as F) must be one of:
3962
** <ul>
3963
** <li> A database filename pointer created by the SQLite core and
3964
** passed into the xOpen() method of a VFS implementation, or
3965
** <li> A filename obtained from [sqlite3_db_filename()], or
3966
** <li> A new filename constructed using [sqlite3_create_filename()].
3967
** </ul>
3968
** If the F parameter is not one of the above, then the behavior is
3969
** undefined and probably undesirable.  Older versions of SQLite were
3970
** more tolerant of invalid F parameters than newer versions.
3971
**
3972
** If F is a suitable filename (as described in the previous paragraph)
3973
** and if P is the name of the query parameter, then
3974
** sqlite3_uri_parameter(F,P) returns the value of the P
3975
** parameter if it exists or a NULL pointer if P does not appear as a
3976
** query parameter on F.  If P is a query parameter of F and it
3977
** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3978
** a pointer to an empty string.
3979
**
3980
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3981
** parameter and returns true (1) or false (0) according to the value
3982
** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3983
** value of query parameter P is one of "yes", "true", or "on" in any
3984
** case or if the value begins with a non-zero number.  The
3985
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3986
** query parameter P is one of "no", "false", or "off" in any case or
3987
** if the value begins with a numeric zero.  If P is not a query
3988
** parameter on F or if the value of P does not match any of the
3989
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
3990
**
3991
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3992
** 64-bit signed integer and returns that integer, or D if P does not
3993
** exist.  If the value of P is something other than an integer, then
3994
** zero is returned.
3995
**
3996
** The sqlite3_uri_key(F,N) returns a pointer to the name (not
3997
** the value) of the N-th query parameter for filename F, or a NULL
3998
** pointer if N is less than zero or greater than the number of query
3999
** parameters minus 1.  The N value is zero-based so N should be 0 to obtain
4000
** the name of the first query parameter, 1 for the second parameter, and
4001
** so forth.
4002
**
4003
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
4004
** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
4005
** is not a database file pathname pointer that the SQLite core passed
4006
** into the xOpen VFS method, then the behavior of this routine is undefined
4007
** and probably undesirable.
4008
**
4009
** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
4010
** parameter can also be the name of a rollback journal file or WAL file
4011
** in addition to the main database file.  Prior to version 3.31.0, these
4012
** routines would only work if F was the name of the main database file.
4013
** When the F parameter is the name of the rollback journal or WAL file,
4014
** it has access to all the same query parameters as were found on the
4015
** main database file.
4016
**
4017
** See the [URI filename] documentation for additional information.
4018
*/
4019
SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam);
4020
SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault);
4021
SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64);
4022
SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N);
4023
4024
/*
4025
** CAPI3REF:  Translate filenames
4026
**
4027
** These routines are available to [VFS|custom VFS implementations] for
4028
** translating filenames between the main database file, the journal file,
4029
** and the WAL file.
4030
**
4031
** If F is the name of an sqlite database file, journal file, or WAL file
4032
** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
4033
** returns the name of the corresponding database file.
4034
**
4035
** If F is the name of an sqlite database file, journal file, or WAL file
4036
** passed by the SQLite core into the VFS, or if F is a database filename
4037
** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
4038
** returns the name of the corresponding rollback journal file.
4039
**
4040
** If F is the name of an sqlite database file, journal file, or WAL file
4041
** that was passed by the SQLite core into the VFS, or if F is a database
4042
** filename obtained from [sqlite3_db_filename()], then
4043
** sqlite3_filename_wal(F) returns the name of the corresponding
4044
** WAL file.
4045
**
4046
** In all of the above, if F is not the name of a database, journal or WAL
4047
** filename passed into the VFS from the SQLite core and F is not the
4048
** return value from [sqlite3_db_filename()], then the result is
4049
** undefined and is likely a memory access violation.
4050
*/
4051
SQLITE_API const char *sqlite3_filename_database(sqlite3_filename);
4052
SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename);
4053
SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename);
4054
4055
/*
4056
** CAPI3REF:  Database File Corresponding To A Journal
4057
**
4058
** ^If X is the name of a rollback or WAL-mode journal file that is
4059
** passed into the xOpen method of [sqlite3_vfs], then
4060
** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
4061
** object that represents the main database file.
4062
**
4063
** This routine is intended for use in custom [VFS] implementations
4064
** only.  It is not a general-purpose interface.
4065
** The argument sqlite3_file_object(X) must be a filename pointer that
4066
** has been passed into [sqlite3_vfs].xOpen method where the
4067
** flags parameter to xOpen contains one of the bits
4068
** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL].  Any other use
4069
** of this routine results in undefined and probably undesirable
4070
** behavior.
4071
*/
4072
SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
4073
4074
/*
4075
** CAPI3REF: Create and Destroy VFS Filenames
4076
**
4077
** These interfaces are provided for use by [VFS shim] implementations and
4078
** are not useful outside of that context.
4079
**
4080
** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
4081
** database filename D with corresponding journal file J and WAL file W and
4082
** an array P of N URI Key/Value pairs.  The result from
4083
** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
4084
** is safe to pass to routines like:
4085
** <ul>
4086
** <li> [sqlite3_uri_parameter()],
4087
** <li> [sqlite3_uri_boolean()],
4088
** <li> [sqlite3_uri_int64()],
4089
** <li> [sqlite3_uri_key()],
4090
** <li> [sqlite3_filename_database()],
4091
** <li> [sqlite3_filename_journal()], or
4092
** <li> [sqlite3_filename_wal()].
4093
** </ul>
4094
** If a memory allocation error occurs, sqlite3_create_filename() might
4095
** return a NULL pointer.  The memory obtained from sqlite3_create_filename(X)
4096
** must be released by a corresponding call to sqlite3_free_filename(Y).
4097
**
4098
** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
4099
** of 2*N pointers to strings.  Each pair of pointers in this array corresponds
4100
** to a key and value for a query parameter.  The P parameter may be a NULL
4101
** pointer if N is zero.  None of the 2*N pointers in the P array may be
4102
** NULL pointers and key pointers should not be empty strings.
4103
** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
4104
** be NULL pointers, though they can be empty strings.
4105
**
4106
** The sqlite3_free_filename(Y) routine releases a memory allocation
4107
** previously obtained from sqlite3_create_filename().  Invoking
4108
** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
4109
**
4110
** If the Y parameter to sqlite3_free_filename(Y) is anything other
4111
** than a NULL pointer or a pointer previously acquired from
4112
** sqlite3_create_filename(), then bad things such as heap
4113
** corruption or segfaults may occur. The value Y should not be
4114
** used again after sqlite3_free_filename(Y) has been called.  This means
4115
** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
4116
** then the corresponding [sqlite3_module.xClose() method should also be
4117
** invoked prior to calling sqlite3_free_filename(Y).
4118
*/
4119
SQLITE_API sqlite3_filename sqlite3_create_filename(
4120
  const char *zDatabase,
4121
  const char *zJournal,
4122
  const char *zWal,
4123
  int nParam,
4124
  const char **azParam
4125
);
4126
SQLITE_API void sqlite3_free_filename(sqlite3_filename);
4127
4128
/*
4129
** CAPI3REF: Error Codes And Messages
4130
** METHOD: sqlite3
4131
**
4132
** ^If the most recent sqlite3_* API call associated with
4133
** [database connection] D failed, then the sqlite3_errcode(D) interface
4134
** returns the numeric [result code] or [extended result code] for that
4135
** API call.
4136
** ^The sqlite3_extended_errcode()
4137
** interface is the same except that it always returns the
4138
** [extended result code] even when extended result codes are
4139
** disabled.
4140
**
4141
** The values returned by sqlite3_errcode() and/or
4142
** sqlite3_extended_errcode() might change with each API call.
4143
** Except, there are some interfaces that are guaranteed to never
4144
** change the value of the error code.  The error-code preserving
4145
** interfaces include the following:
4146
**
4147
** <ul>
4148
** <li> sqlite3_errcode()
4149
** <li> sqlite3_extended_errcode()
4150
** <li> sqlite3_errmsg()
4151
** <li> sqlite3_errmsg16()
4152
** <li> sqlite3_error_offset()
4153
** </ul>
4154
**
4155
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
4156
** text that describes the error, as either UTF-8 or UTF-16 respectively,
4157
** or NULL if no error message is available.
4158
** (See how SQLite handles [invalid UTF] for exceptions to this rule.)
4159
** ^(Memory to hold the error message string is managed internally.
4160
** The application does not need to worry about freeing the result.
4161
** However, the error string might be overwritten or deallocated by
4162
** subsequent calls to other SQLite interface functions.)^
4163
**
4164
** ^The sqlite3_errstr(E) interface returns the English-language text
4165
** that describes the [result code] E, as UTF-8, or NULL if E is not an
4166
** result code for which a text error message is available.
4167
** ^(Memory to hold the error message string is managed internally
4168
** and must not be freed by the application)^.
4169
**
4170
** ^If the most recent error references a specific token in the input
4171
** SQL, the sqlite3_error_offset() interface returns the byte offset
4172
** of the start of that token.  ^The byte offset returned by
4173
** sqlite3_error_offset() assumes that the input SQL is UTF8.
4174
** ^If the most recent error does not reference a specific token in the input
4175
** SQL, then the sqlite3_error_offset() function returns -1.
4176
**
4177
** When the serialized [threading mode] is in use, it might be the
4178
** case that a second error occurs on a separate thread in between
4179
** the time of the first error and the call to these interfaces.
4180
** When that happens, the second error will be reported since these
4181
** interfaces always report the most recent result.  To avoid
4182
** this, each thread can obtain exclusive use of the [database connection] D
4183
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
4184
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
4185
** all calls to the interfaces listed here are completed.
4186
**
4187
** If an interface fails with SQLITE_MISUSE, that means the interface
4188
** was invoked incorrectly by the application.  In that case, the
4189
** error code and message may or may not be set.
4190
*/
4191
SQLITE_API int sqlite3_errcode(sqlite3 *db);
4192
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
4193
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
4194
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
4195
SQLITE_API const char *sqlite3_errstr(int);
4196
SQLITE_API int sqlite3_error_offset(sqlite3 *db);
4197
4198
/*
4199
** CAPI3REF: Prepared Statement Object
4200
** KEYWORDS: {prepared statement} {prepared statements}
4201
**
4202
** An instance of this object represents a single SQL statement that
4203
** has been compiled into binary form and is ready to be evaluated.
4204
**
4205
** Think of each SQL statement as a separate computer program.  The
4206
** original SQL text is source code.  A prepared statement object
4207
** is the compiled object code.  All SQL must be converted into a
4208
** prepared statement before it can be run.
4209
**
4210
** The life-cycle of a prepared statement object usually goes like this:
4211
**
4212
** <ol>
4213
** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
4214
** <li> Bind values to [parameters] using the sqlite3_bind_*()
4215
**      interfaces.
4216
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
4217
** <li> Reset the prepared statement using [sqlite3_reset()] then go back
4218
**      to step 2.  Do this zero or more times.
4219
** <li> Destroy the object using [sqlite3_finalize()].
4220
** </ol>
4221
*/
4222
typedef struct sqlite3_stmt sqlite3_stmt;
4223
4224
/*
4225
** CAPI3REF: Run-time Limits
4226
** METHOD: sqlite3
4227
**
4228
** ^(This interface allows the size of various constructs to be limited
4229
** on a connection by connection basis.  The first parameter is the
4230
** [database connection] whose limit is to be set or queried.  The
4231
** second parameter is one of the [limit categories] that define a
4232
** class of constructs to be size limited.  The third parameter is the
4233
** new limit for that construct.)^
4234
**
4235
** ^If the new limit is a negative number, the limit is unchanged.
4236
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
4237
** [limits | hard upper bound]
4238
** set at compile-time by a C preprocessor macro called
4239
** [limits | SQLITE_MAX_<i>NAME</i>].
4240
** (The "_LIMIT_" in the name is changed to "_MAX_".))^
4241
** ^Attempts to increase a limit above its hard upper bound are
4242
** silently truncated to the hard upper bound.
4243
**
4244
** ^Regardless of whether or not the limit was changed, the
4245
** [sqlite3_limit()] interface returns the prior value of the limit.
4246
** ^Hence, to find the current value of a limit without changing it,
4247
** simply invoke this interface with the third parameter set to -1.
4248
**
4249
** Run-time limits are intended for use in applications that manage
4250
** both their own internal database and also databases that are controlled
4251
** by untrusted external sources.  An example application might be a
4252
** web browser that has its own databases for storing history and
4253
** separate databases controlled by JavaScript applications downloaded
4254
** off the Internet.  The internal databases can be given the
4255
** large, default limits.  Databases managed by external sources can
4256
** be given much smaller limits designed to prevent a denial of service
4257
** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
4258
** interface to further control untrusted SQL.  The size of the database
4259
** created by an untrusted script can be contained using the
4260
** [max_page_count] [PRAGMA].
4261
**
4262
** New run-time limit categories may be added in future releases.
4263
*/
4264
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
4265
4266
/*
4267
** CAPI3REF: Run-Time Limit Categories
4268
** KEYWORDS: {limit category} {*limit categories}
4269
**
4270
** These constants define various performance limits
4271
** that can be lowered at run-time using [sqlite3_limit()].
4272
** The synopsis of the meanings of the various limits is shown below.
4273
** Additional information is available at [limits | Limits in SQLite].
4274
**
4275
** <dl>
4276
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
4277
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
4278
**
4279
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
4280
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
4281
**
4282
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
4283
** <dd>The maximum number of columns in a table definition or in the
4284
** result set of a [SELECT] or the maximum number of columns in an index
4285
** or in an ORDER BY or GROUP BY clause.</dd>)^
4286
**
4287
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
4288
** <dd>The maximum depth of the parse tree on any expression.</dd>)^
4289
**
4290
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
4291
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
4292
**
4293
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
4294
** <dd>The maximum number of instructions in a virtual machine program
4295
** used to implement an SQL statement.  If [sqlite3_prepare_v2()] or
4296
** the equivalent tries to allocate space for more than this many opcodes
4297
** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
4298
**
4299
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
4300
** <dd>The maximum number of arguments on a function.</dd>)^
4301
**
4302
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
4303
** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
4304
**
4305
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
4306
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
4307
** <dd>The maximum length of the pattern argument to the [LIKE] or
4308
** [GLOB] operators.</dd>)^
4309
**
4310
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
4311
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
4312
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
4313
**
4314
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
4315
** <dd>The maximum depth of recursion for triggers.</dd>)^
4316
**
4317
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
4318
** <dd>The maximum number of auxiliary worker threads that a single
4319
** [prepared statement] may start.</dd>)^
4320
** </dl>
4321
*/
4322
#define SQLITE_LIMIT_LENGTH                    0
4323
#define SQLITE_LIMIT_SQL_LENGTH                1
4324
#define SQLITE_LIMIT_COLUMN                    2
4325
#define SQLITE_LIMIT_EXPR_DEPTH                3
4326
#define SQLITE_LIMIT_COMPOUND_SELECT           4
4327
#define SQLITE_LIMIT_VDBE_OP                   5
4328
#define SQLITE_LIMIT_FUNCTION_ARG              6
4329
#define SQLITE_LIMIT_ATTACHED                  7
4330
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
4331
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
4332
#define SQLITE_LIMIT_TRIGGER_DEPTH            10
4333
#define SQLITE_LIMIT_WORKER_THREADS           11
4334
4335
/*
4336
** CAPI3REF: Prepare Flags
4337
**
4338
** These constants define various flags that can be passed into
4339
** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
4340
** [sqlite3_prepare16_v3()] interfaces.
4341
**
4342
** New flags may be added in future releases of SQLite.
4343
**
4344
** <dl>
4345
** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
4346
** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
4347
** that the prepared statement will be retained for a long time and
4348
** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
4349
** and [sqlite3_prepare16_v3()] assume that the prepared statement will
4350
** be used just once or at most a few times and then destroyed using
4351
** [sqlite3_finalize()] relatively soon. The current implementation acts
4352
** on this hint by avoiding the use of [lookaside memory] so as not to
4353
** deplete the limited store of lookaside memory. Future versions of
4354
** SQLite may act on this hint differently.
4355
**
4356
** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
4357
** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
4358
** to be required for any prepared statement that wanted to use the
4359
** [sqlite3_normalized_sql()] interface.  However, the
4360
** [sqlite3_normalized_sql()] interface is now available to all
4361
** prepared statements, regardless of whether or not they use this
4362
** flag.
4363
**
4364
** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
4365
** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
4366
** to return an error (error code SQLITE_ERROR) if the statement uses
4367
** any virtual tables.
4368
**
4369
** [[SQLITE_PREPARE_DONT_LOG]] <dt>SQLITE_PREPARE_DONT_LOG</dt>
4370
** <dd>The SQLITE_PREPARE_DONT_LOG flag prevents SQL compiler
4371
** errors from being sent to the error log defined by
4372
** [SQLITE_CONFIG_LOG].  This can be used, for example, to do test
4373
** compiles to see if some SQL syntax is well-formed, without generating
4374
** messages on the global error log when it is not.  If the test compile
4375
** fails, the sqlite3_prepare_v3() call returns the same error indications
4376
** with or without this flag; it just omits the call to [sqlite3_log()] that
4377
** logs the error.
4378
** </dl>
4379
*/
4380
#define SQLITE_PREPARE_PERSISTENT              0x01
4381
#define SQLITE_PREPARE_NORMALIZE               0x02
4382
#define SQLITE_PREPARE_NO_VTAB                 0x04
4383
#define SQLITE_PREPARE_DONT_LOG                0x10
4384
4385
/*
4386
** CAPI3REF: Compiling An SQL Statement
4387
** KEYWORDS: {SQL statement compiler}
4388
** METHOD: sqlite3
4389
** CONSTRUCTOR: sqlite3_stmt
4390
**
4391
** To execute an SQL statement, it must first be compiled into a byte-code
4392
** program using one of these routines.  Or, in other words, these routines
4393
** are constructors for the [prepared statement] object.
4394
**
4395
** The preferred routine to use is [sqlite3_prepare_v2()].  The
4396
** [sqlite3_prepare()] interface is legacy and should be avoided.
4397
** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
4398
** for special purposes.
4399
**
4400
** The use of the UTF-8 interfaces is preferred, as SQLite currently
4401
** does all parsing using UTF-8.  The UTF-16 interfaces are provided
4402
** as a convenience.  The UTF-16 interfaces work by converting the
4403
** input text into UTF-8, then invoking the corresponding UTF-8 interface.
4404
**
4405
** The first argument, "db", is a [database connection] obtained from a
4406
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
4407
** [sqlite3_open16()].  The database connection must not have been closed.
4408
**
4409
** The second argument, "zSql", is the statement to be compiled, encoded
4410
** as either UTF-8 or UTF-16.  The sqlite3_prepare(), sqlite3_prepare_v2(),
4411
** and sqlite3_prepare_v3()
4412
** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
4413
** and sqlite3_prepare16_v3() use UTF-16.
4414
**
4415
** ^If the nByte argument is negative, then zSql is read up to the
4416
** first zero terminator. ^If nByte is positive, then it is the maximum
4417
** number of bytes read from zSql.  When nByte is positive, zSql is read
4418
** up to the first zero terminator or until the nByte bytes have been read,
4419
** whichever comes first.  ^If nByte is zero, then no prepared
4420
** statement is generated.
4421
** If the caller knows that the supplied string is nul-terminated, then
4422
** there is a small performance advantage to passing an nByte parameter that
4423
** is the number of bytes in the input string <i>including</i>
4424
** the nul-terminator.
4425
** Note that nByte measure the length of the input in bytes, not
4426
** characters, even for the UTF-16 interfaces.
4427
**
4428
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
4429
** past the end of the first SQL statement in zSql.  These routines only
4430
** compile the first statement in zSql, so *pzTail is left pointing to
4431
** what remains uncompiled.
4432
**
4433
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
4434
** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
4435
** to NULL.  ^If the input text contains no SQL (if the input is an empty
4436
** string or a comment) then *ppStmt is set to NULL.
4437
** The calling procedure is responsible for deleting the compiled
4438
** SQL statement using [sqlite3_finalize()] after it has finished with it.
4439
** ppStmt may not be NULL.
4440
**
4441
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
4442
** otherwise an [error code] is returned.
4443
**
4444
** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
4445
** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
4446
** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
4447
** are retained for backwards compatibility, but their use is discouraged.
4448
** ^In the "vX" interfaces, the prepared statement
4449
** that is returned (the [sqlite3_stmt] object) contains a copy of the
4450
** original SQL text. This causes the [sqlite3_step()] interface to
4451
** behave differently in three ways:
4452
**
4453
** <ol>
4454
** <li>
4455
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
4456
** always used to do, [sqlite3_step()] will automatically recompile the SQL
4457
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
4458
** retries will occur before sqlite3_step() gives up and returns an error.
4459
** </li>
4460
**
4461
** <li>
4462
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
4463
** [error codes] or [extended error codes].  ^The legacy behavior was that
4464
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
4465
** and the application would have to make a second call to [sqlite3_reset()]
4466
** in order to find the underlying cause of the problem. With the "v2" prepare
4467
** interfaces, the underlying reason for the error is returned immediately.
4468
** </li>
4469
**
4470
** <li>
4471
** ^If the specific value bound to a [parameter | host parameter] in the
4472
** WHERE clause might influence the choice of query plan for a statement,
4473
** then the statement will be automatically recompiled, as if there had been
4474
** a schema change, on the first [sqlite3_step()] call following any change
4475
** to the [sqlite3_bind_text | bindings] of that [parameter].
4476
** ^The specific value of a WHERE-clause [parameter] might influence the
4477
** choice of query plan if the parameter is the left-hand side of a [LIKE]
4478
** or [GLOB] operator or if the parameter is compared to an indexed column
4479
** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
4480
** </li>
4481
** </ol>
4482
**
4483
** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
4484
** the extra prepFlags parameter, which is a bit array consisting of zero or
4485
** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags.  ^The
4486
** sqlite3_prepare_v2() interface works exactly the same as
4487
** sqlite3_prepare_v3() with a zero prepFlags parameter.
4488
*/
4489
SQLITE_API int sqlite3_prepare(
4490
  sqlite3 *db,            /* Database handle */
4491
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4492
  int nByte,              /* Maximum length of zSql in bytes. */
4493
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4494
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4495
);
4496
SQLITE_API int sqlite3_prepare_v2(
4497
  sqlite3 *db,            /* Database handle */
4498
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4499
  int nByte,              /* Maximum length of zSql in bytes. */
4500
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4501
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4502
);
4503
SQLITE_API int sqlite3_prepare_v3(
4504
  sqlite3 *db,            /* Database handle */
4505
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4506
  int nByte,              /* Maximum length of zSql in bytes. */
4507
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4508
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4509
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4510
);
4511
SQLITE_API int sqlite3_prepare16(
4512
  sqlite3 *db,            /* Database handle */
4513
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4514
  int nByte,              /* Maximum length of zSql in bytes. */
4515
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4516
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4517
);
4518
SQLITE_API int sqlite3_prepare16_v2(
4519
  sqlite3 *db,            /* Database handle */
4520
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4521
  int nByte,              /* Maximum length of zSql in bytes. */
4522
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4523
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4524
);
4525
SQLITE_API int sqlite3_prepare16_v3(
4526
  sqlite3 *db,            /* Database handle */
4527
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4528
  int nByte,              /* Maximum length of zSql in bytes. */
4529
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4530
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4531
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4532
);
4533
4534
/*
4535
** CAPI3REF: Retrieving Statement SQL
4536
** METHOD: sqlite3_stmt
4537
**
4538
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
4539
** SQL text used to create [prepared statement] P if P was
4540
** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
4541
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4542
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
4543
** string containing the SQL text of prepared statement P with
4544
** [bound parameters] expanded.
4545
** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
4546
** string containing the normalized SQL text of prepared statement P.  The
4547
** semantics used to normalize a SQL statement are unspecified and subject
4548
** to change.  At a minimum, literal values will be replaced with suitable
4549
** placeholders.
4550
**
4551
** ^(For example, if a prepared statement is created using the SQL
4552
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
4553
** and parameter :xyz is unbound, then sqlite3_sql() will return
4554
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
4555
** will return "SELECT 2345,NULL".)^
4556
**
4557
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
4558
** is available to hold the result, or if the result would exceed the
4559
** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
4560
**
4561
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
4562
** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
4563
** option causes sqlite3_expanded_sql() to always return NULL.
4564
**
4565
** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
4566
** are managed by SQLite and are automatically freed when the prepared
4567
** statement is finalized.
4568
** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
4569
** is obtained from [sqlite3_malloc()] and must be freed by the application
4570
** by passing it to [sqlite3_free()].
4571
**
4572
** ^The sqlite3_normalized_sql() interface is only available if
4573
** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined.
4574
*/
4575
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
4576
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
4577
#ifdef SQLITE_ENABLE_NORMALIZE
4578
SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
4579
#endif
4580
4581
/*
4582
** CAPI3REF: Determine If An SQL Statement Writes The Database
4583
** METHOD: sqlite3_stmt
4584
**
4585
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
4586
** and only if the [prepared statement] X makes no direct changes to
4587
** the content of the database file.
4588
**
4589
** Note that [application-defined SQL functions] or
4590
** [virtual tables] might change the database indirectly as a side effect.
4591
** ^(For example, if an application defines a function "eval()" that
4592
** calls [sqlite3_exec()], then the following SQL statement would
4593
** change the database file through side-effects:
4594
**
4595
** <blockquote><pre>
4596
**    SELECT eval('DELETE FROM t1') FROM t2;
4597
** </pre></blockquote>
4598
**
4599
** But because the [SELECT] statement does not change the database file
4600
** directly, sqlite3_stmt_readonly() would still return true.)^
4601
**
4602
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
4603
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
4604
** since the statements themselves do not actually modify the database but
4605
** rather they control the timing of when other statements modify the
4606
** database.  ^The [ATTACH] and [DETACH] statements also cause
4607
** sqlite3_stmt_readonly() to return true since, while those statements
4608
** change the configuration of a database connection, they do not make
4609
** changes to the content of the database files on disk.
4610
** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
4611
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
4612
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
4613
** sqlite3_stmt_readonly() returns false for those commands.
4614
**
4615
** ^This routine returns false if there is any possibility that the
4616
** statement might change the database file.  ^A false return does
4617
** not guarantee that the statement will change the database file.
4618
** ^For example, an UPDATE statement might have a WHERE clause that
4619
** makes it a no-op, but the sqlite3_stmt_readonly() result would still
4620
** be false.  ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a
4621
** read-only no-op if the table already exists, but
4622
** sqlite3_stmt_readonly() still returns false for such a statement.
4623
**
4624
** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN]
4625
** statement, then sqlite3_stmt_readonly(X) returns the same value as
4626
** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted.
4627
*/
4628
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
4629
4630
/*
4631
** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
4632
** METHOD: sqlite3_stmt
4633
**
4634
** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
4635
** prepared statement S is an EXPLAIN statement, or 2 if the
4636
** statement S is an EXPLAIN QUERY PLAN.
4637
** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
4638
** an ordinary statement or a NULL pointer.
4639
*/
4640
SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
4641
4642
/*
4643
** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement
4644
** METHOD: sqlite3_stmt
4645
**
4646
** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN
4647
** setting for [prepared statement] S.  If E is zero, then S becomes
4648
** a normal prepared statement.  If E is 1, then S behaves as if
4649
** its SQL text began with "[EXPLAIN]".  If E is 2, then S behaves as if
4650
** its SQL text began with "[EXPLAIN QUERY PLAN]".
4651
**
4652
** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared.
4653
** SQLite tries to avoid a reprepare, but a reprepare might be necessary
4654
** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode.
4655
**
4656
** Because of the potential need to reprepare, a call to
4657
** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be
4658
** reprepared because it was created using [sqlite3_prepare()] instead of
4659
** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and
4660
** hence has no saved SQL text with which to reprepare.
4661
**
4662
** Changing the explain setting for a prepared statement does not change
4663
** the original SQL text for the statement.  Hence, if the SQL text originally
4664
** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0)
4665
** is called to convert the statement into an ordinary statement, the EXPLAIN
4666
** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S)
4667
** output, even though the statement now acts like a normal SQL statement.
4668
**
4669
** This routine returns SQLITE_OK if the explain mode is successfully
4670
** changed, or an error code if the explain mode could not be changed.
4671
** The explain mode cannot be changed while a statement is active.
4672
** Hence, it is good practice to call [sqlite3_reset(S)]
4673
** immediately prior to calling sqlite3_stmt_explain(S,E).
4674
*/
4675
SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode);
4676
4677
/*
4678
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
4679
** METHOD: sqlite3_stmt
4680
**
4681
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
4682
** [prepared statement] S has been stepped at least once using
4683
** [sqlite3_step(S)] but has neither run to completion (returned
4684
** [SQLITE_DONE] from [sqlite3_step(S)]) nor
4685
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
4686
** interface returns false if S is a NULL pointer.  If S is not a
4687
** NULL pointer and is not a pointer to a valid [prepared statement]
4688
** object, then the behavior is undefined and probably undesirable.
4689
**
4690
** This interface can be used in combination [sqlite3_next_stmt()]
4691
** to locate all prepared statements associated with a database
4692
** connection that are in need of being reset.  This can be used,
4693
** for example, in diagnostic routines to search for prepared
4694
** statements that are holding a transaction open.
4695
*/
4696
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
4697
4698
/*
4699
** CAPI3REF: Dynamically Typed Value Object
4700
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
4701
**
4702
** SQLite uses the sqlite3_value object to represent all values
4703
** that can be stored in a database table. SQLite uses dynamic typing
4704
** for the values it stores.  ^Values stored in sqlite3_value objects
4705
** can be integers, floating point values, strings, BLOBs, or NULL.
4706
**
4707
** An sqlite3_value object may be either "protected" or "unprotected".
4708
** Some interfaces require a protected sqlite3_value.  Other interfaces
4709
** will accept either a protected or an unprotected sqlite3_value.
4710
** Every interface that accepts sqlite3_value arguments specifies
4711
** whether or not it requires a protected sqlite3_value.  The
4712
** [sqlite3_value_dup()] interface can be used to construct a new
4713
** protected sqlite3_value from an unprotected sqlite3_value.
4714
**
4715
** The terms "protected" and "unprotected" refer to whether or not
4716
** a mutex is held.  An internal mutex is held for a protected
4717
** sqlite3_value object but no mutex is held for an unprotected
4718
** sqlite3_value object.  If SQLite is compiled to be single-threaded
4719
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
4720
** or if SQLite is run in one of reduced mutex modes
4721
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
4722
** then there is no distinction between protected and unprotected
4723
** sqlite3_value objects and they can be used interchangeably.  However,
4724
** for maximum code portability it is recommended that applications
4725
** still make the distinction between protected and unprotected
4726
** sqlite3_value objects even when not strictly required.
4727
**
4728
** ^The sqlite3_value objects that are passed as parameters into the
4729
** implementation of [application-defined SQL functions] are protected.
4730
** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()]
4731
** are protected.
4732
** ^The sqlite3_value object returned by
4733
** [sqlite3_column_value()] is unprotected.
4734
** Unprotected sqlite3_value objects may only be used as arguments
4735
** to [sqlite3_result_value()], [sqlite3_bind_value()], and
4736
** [sqlite3_value_dup()].
4737
** The [sqlite3_value_blob | sqlite3_value_type()] family of
4738
** interfaces require protected sqlite3_value objects.
4739
*/
4740
typedef struct sqlite3_value sqlite3_value;
4741
4742
/*
4743
** CAPI3REF: SQL Function Context Object
4744
**
4745
** The context in which an SQL function executes is stored in an
4746
** sqlite3_context object.  ^A pointer to an sqlite3_context object
4747
** is always first parameter to [application-defined SQL functions].
4748
** The application-defined SQL function implementation will pass this
4749
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
4750
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
4751
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
4752
** and/or [sqlite3_set_auxdata()].
4753
*/
4754
typedef struct sqlite3_context sqlite3_context;
4755
4756
/*
4757
** CAPI3REF: Binding Values To Prepared Statements
4758
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
4759
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
4760
** METHOD: sqlite3_stmt
4761
**
4762
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
4763
** literals may be replaced by a [parameter] that matches one of the following
4764
** templates:
4765
**
4766
** <ul>
4767
** <li>  ?
4768
** <li>  ?NNN
4769
** <li>  :VVV
4770
** <li>  @VVV
4771
** <li>  $VVV
4772
** </ul>
4773
**
4774
** In the templates above, NNN represents an integer literal,
4775
** and VVV represents an alphanumeric identifier.)^  ^The values of these
4776
** parameters (also called "host parameter names" or "SQL parameters")
4777
** can be set using the sqlite3_bind_*() routines defined here.
4778
**
4779
** ^The first argument to the sqlite3_bind_*() routines is always
4780
** a pointer to the [sqlite3_stmt] object returned from
4781
** [sqlite3_prepare_v2()] or its variants.
4782
**
4783
** ^The second argument is the index of the SQL parameter to be set.
4784
** ^The leftmost SQL parameter has an index of 1.  ^When the same named
4785
** SQL parameter is used more than once, second and subsequent
4786
** occurrences have the same index as the first occurrence.
4787
** ^The index for named parameters can be looked up using the
4788
** [sqlite3_bind_parameter_index()] API if desired.  ^The index
4789
** for "?NNN" parameters is the value of NNN.
4790
** ^The NNN value must be between 1 and the [sqlite3_limit()]
4791
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
4792
**
4793
** ^The third argument is the value to bind to the parameter.
4794
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4795
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
4796
** is ignored and the end result is the same as sqlite3_bind_null().
4797
** ^If the third parameter to sqlite3_bind_text() is not NULL, then
4798
** it should be a pointer to well-formed UTF8 text.
4799
** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
4800
** it should be a pointer to well-formed UTF16 text.
4801
** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
4802
** it should be a pointer to a well-formed unicode string that is
4803
** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16
4804
** otherwise.
4805
**
4806
** [[byte-order determination rules]] ^The byte-order of
4807
** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
4808
** found in the first character, which is removed, or in the absence of a BOM
4809
** the byte order is the native byte order of the host
4810
** machine for sqlite3_bind_text16() or the byte order specified in
4811
** the 6th parameter for sqlite3_bind_text64().)^
4812
** ^If UTF16 input text contains invalid unicode
4813
** characters, then SQLite might change those invalid characters
4814
** into the unicode replacement character: U+FFFD.
4815
**
4816
** ^(In those routines that have a fourth argument, its value is the
4817
** number of bytes in the parameter.  To be clear: the value is the
4818
** number of <u>bytes</u> in the value, not the number of characters.)^
4819
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4820
** is negative, then the length of the string is
4821
** the number of bytes up to the first zero terminator.
4822
** If the fourth parameter to sqlite3_bind_blob() is negative, then
4823
** the behavior is undefined.
4824
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
4825
** or sqlite3_bind_text16() or sqlite3_bind_text64() then
4826
** that parameter must be the byte offset
4827
** where the NUL terminator would occur assuming the string were NUL
4828
** terminated.  If any NUL characters occur at byte offsets less than
4829
** the value of the fourth parameter then the resulting string value will
4830
** contain embedded NULs.  The result of expressions involving strings
4831
** with embedded NULs is undefined.
4832
**
4833
** ^The fifth argument to the BLOB and string binding interfaces controls
4834
** or indicates the lifetime of the object referenced by the third parameter.
4835
** These three options exist:
4836
** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished
4837
** with it may be passed. ^It is called to dispose of the BLOB or string even
4838
** if the call to the bind API fails, except the destructor is not called if
4839
** the third parameter is a NULL pointer or the fourth parameter is negative.
4840
** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that
4841
** the application remains responsible for disposing of the object. ^In this
4842
** case, the object and the provided pointer to it must remain valid until
4843
** either the prepared statement is finalized or the same SQL parameter is
4844
** bound to something else, whichever occurs sooner.
4845
** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the
4846
** object is to be copied prior to the return from sqlite3_bind_*(). ^The
4847
** object and pointer to it must remain valid until then. ^SQLite will then
4848
** manage the lifetime of its private copy.
4849
**
4850
** ^The sixth argument to sqlite3_bind_text64() must be one of
4851
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
4852
** to specify the encoding of the text in the third parameter.  If
4853
** the sixth argument to sqlite3_bind_text64() is not one of the
4854
** allowed values shown above, or if the text encoding is different
4855
** from the encoding specified by the sixth parameter, then the behavior
4856
** is undefined.
4857
**
4858
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
4859
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
4860
** (just an integer to hold its size) while it is being processed.
4861
** Zeroblobs are intended to serve as placeholders for BLOBs whose
4862
** content is later written using
4863
** [sqlite3_blob_open | incremental BLOB I/O] routines.
4864
** ^A negative value for the zeroblob results in a zero-length BLOB.
4865
**
4866
** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
4867
** [prepared statement] S to have an SQL value of NULL, but to also be
4868
** associated with the pointer P of type T.  ^D is either a NULL pointer or
4869
** a pointer to a destructor function for P. ^SQLite will invoke the
4870
** destructor D with a single argument of P when it is finished using
4871
** P.  The T parameter should be a static string, preferably a string
4872
** literal. The sqlite3_bind_pointer() routine is part of the
4873
** [pointer passing interface] added for SQLite 3.20.0.
4874
**
4875
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
4876
** for the [prepared statement] or with a prepared statement for which
4877
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
4878
** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
4879
** routine is passed a [prepared statement] that has been finalized, the
4880
** result is undefined and probably harmful.
4881
**
4882
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
4883
** ^Unbound parameters are interpreted as NULL.
4884
**
4885
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
4886
** [error code] if anything goes wrong.
4887
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
4888
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
4889
** [SQLITE_MAX_LENGTH].
4890
** ^[SQLITE_RANGE] is returned if the parameter
4891
** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
4892
**
4893
** See also: [sqlite3_bind_parameter_count()],
4894
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
4895
*/
4896
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
4897
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
4898
                        void(*)(void*));
4899
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
4900
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
4901
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
4902
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
4903
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
4904
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
4905
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
4906
                         void(*)(void*), unsigned char encoding);
4907
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
4908
SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
4909
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
4910
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
4911
4912
/*
4913
** CAPI3REF: Number Of SQL Parameters
4914
** METHOD: sqlite3_stmt
4915
**
4916
** ^This routine can be used to find the number of [SQL parameters]
4917
** in a [prepared statement].  SQL parameters are tokens of the
4918
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
4919
** placeholders for values that are [sqlite3_bind_blob | bound]
4920
** to the parameters at a later time.
4921
**
4922
** ^(This routine actually returns the index of the largest (rightmost)
4923
** parameter. For all forms except ?NNN, this will correspond to the
4924
** number of unique parameters.  If parameters of the ?NNN form are used,
4925
** there may be gaps in the list.)^
4926
**
4927
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4928
** [sqlite3_bind_parameter_name()], and
4929
** [sqlite3_bind_parameter_index()].
4930
*/
4931
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
4932
4933
/*
4934
** CAPI3REF: Name Of A Host Parameter
4935
** METHOD: sqlite3_stmt
4936
**
4937
** ^The sqlite3_bind_parameter_name(P,N) interface returns
4938
** the name of the N-th [SQL parameter] in the [prepared statement] P.
4939
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
4940
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
4941
** respectively.
4942
** In other words, the initial ":" or "$" or "@" or "?"
4943
** is included as part of the name.)^
4944
** ^Parameters of the form "?" without a following integer have no name
4945
** and are referred to as "nameless" or "anonymous parameters".
4946
**
4947
** ^The first host parameter has an index of 1, not 0.
4948
**
4949
** ^If the value N is out of range or if the N-th parameter is
4950
** nameless, then NULL is returned.  ^The returned string is
4951
** always in UTF-8 encoding even if the named parameter was
4952
** originally specified as UTF-16 in [sqlite3_prepare16()],
4953
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4954
**
4955
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4956
** [sqlite3_bind_parameter_count()], and
4957
** [sqlite3_bind_parameter_index()].
4958
*/
4959
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
4960
4961
/*
4962
** CAPI3REF: Index Of A Parameter With A Given Name
4963
** METHOD: sqlite3_stmt
4964
**
4965
** ^Return the index of an SQL parameter given its name.  ^The
4966
** index value returned is suitable for use as the second
4967
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
4968
** is returned if no matching parameter is found.  ^The parameter
4969
** name must be given in UTF-8 even if the original statement
4970
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
4971
** [sqlite3_prepare16_v3()].
4972
**
4973
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4974
** [sqlite3_bind_parameter_count()], and
4975
** [sqlite3_bind_parameter_name()].
4976
*/
4977
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
4978
4979
/*
4980
** CAPI3REF: Reset All Bindings On A Prepared Statement
4981
** METHOD: sqlite3_stmt
4982
**
4983
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
4984
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
4985
** ^Use this routine to reset all host parameters to NULL.
4986
*/
4987
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
4988
4989
/*
4990
** CAPI3REF: Number Of Columns In A Result Set
4991
** METHOD: sqlite3_stmt
4992
**
4993
** ^Return the number of columns in the result set returned by the
4994
** [prepared statement]. ^If this routine returns 0, that means the
4995
** [prepared statement] returns no data (for example an [UPDATE]).
4996
** ^However, just because this routine returns a positive number does not
4997
** mean that one or more rows of data will be returned.  ^A SELECT statement
4998
** will always have a positive sqlite3_column_count() but depending on the
4999
** WHERE clause constraints and the table content, it might return no rows.
5000
**
5001
** See also: [sqlite3_data_count()]
5002
*/
5003
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
5004
5005
/*
5006
** CAPI3REF: Column Names In A Result Set
5007
** METHOD: sqlite3_stmt
5008
**
5009
** ^These routines return the name assigned to a particular column
5010
** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
5011
** interface returns a pointer to a zero-terminated UTF-8 string
5012
** and sqlite3_column_name16() returns a pointer to a zero-terminated
5013
** UTF-16 string.  ^The first parameter is the [prepared statement]
5014
** that implements the [SELECT] statement. ^The second parameter is the
5015
** column number.  ^The leftmost column is number 0.
5016
**
5017
** ^The returned string pointer is valid until either the [prepared statement]
5018
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
5019
** reprepared by the first call to [sqlite3_step()] for a particular run
5020
** or until the next call to
5021
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
5022
**
5023
** ^If sqlite3_malloc() fails during the processing of either routine
5024
** (for example during a conversion from UTF-8 to UTF-16) then a
5025
** NULL pointer is returned.
5026
**
5027
** ^The name of a result column is the value of the "AS" clause for
5028
** that column, if there is an AS clause.  If there is no AS clause
5029
** then the name of the column is unspecified and may change from
5030
** one release of SQLite to the next.
5031
*/
5032
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
5033
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
5034
5035
/*
5036
** CAPI3REF: Source Of Data In A Query Result
5037
** METHOD: sqlite3_stmt
5038
**
5039
** ^These routines provide a means to determine the database, table, and
5040
** table column that is the origin of a particular result column in a
5041
** [SELECT] statement.
5042
** ^The name of the database or table or column can be returned as
5043
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
5044
** the database name, the _table_ routines return the table name, and
5045
** the origin_ routines return the column name.
5046
** ^The returned string is valid until the [prepared statement] is destroyed
5047
** using [sqlite3_finalize()] or until the statement is automatically
5048
** reprepared by the first call to [sqlite3_step()] for a particular run
5049
** or until the same information is requested
5050
** again in a different encoding.
5051
**
5052
** ^The names returned are the original un-aliased names of the
5053
** database, table, and column.
5054
**
5055
** ^The first argument to these interfaces is a [prepared statement].
5056
** ^These functions return information about the Nth result column returned by
5057
** the statement, where N is the second function argument.
5058
** ^The left-most column is column 0 for these routines.
5059
**
5060
** ^If the Nth column returned by the statement is an expression or
5061
** subquery and is not a column value, then all of these functions return
5062
** NULL.  ^These routines might also return NULL if a memory allocation error
5063
** occurs.  ^Otherwise, they return the name of the attached database, table,
5064
** or column that query result column was extracted from.
5065
**
5066
** ^As with all other SQLite APIs, those whose names end with "16" return
5067
** UTF-16 encoded strings and the other functions return UTF-8.
5068
**
5069
** ^These APIs are only available if the library was compiled with the
5070
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
5071
**
5072
** If two or more threads call one or more
5073
** [sqlite3_column_database_name | column metadata interfaces]
5074
** for the same [prepared statement] and result column
5075
** at the same time then the results are undefined.
5076
*/
5077
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
5078
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
5079
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
5080
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
5081
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
5082
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
5083
5084
/*
5085
** CAPI3REF: Declared Datatype Of A Query Result
5086
** METHOD: sqlite3_stmt
5087
**
5088
** ^(The first parameter is a [prepared statement].
5089
** If this statement is a [SELECT] statement and the Nth column of the
5090
** returned result set of that [SELECT] is a table column (not an
5091
** expression or subquery) then the declared type of the table
5092
** column is returned.)^  ^If the Nth column of the result set is an
5093
** expression or subquery, then a NULL pointer is returned.
5094
** ^The returned string is always UTF-8 encoded.
5095
**
5096
** ^(For example, given the database schema:
5097
**
5098
** CREATE TABLE t1(c1 VARIANT);
5099
**
5100
** and the following statement to be compiled:
5101
**
5102
** SELECT c1 + 1, c1 FROM t1;
5103
**
5104
** this routine would return the string "VARIANT" for the second result
5105
** column (i==1), and a NULL pointer for the first result column (i==0).)^
5106
**
5107
** ^SQLite uses dynamic run-time typing.  ^So just because a column
5108
** is declared to contain a particular type does not mean that the
5109
** data stored in that column is of the declared type.  SQLite is
5110
** strongly typed, but the typing is dynamic not static.  ^Type
5111
** is associated with individual values, not with the containers
5112
** used to hold those values.
5113
*/
5114
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
5115
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
5116
5117
/*
5118
** CAPI3REF: Evaluate An SQL Statement
5119
** METHOD: sqlite3_stmt
5120
**
5121
** After a [prepared statement] has been prepared using any of
5122
** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
5123
** or [sqlite3_prepare16_v3()] or one of the legacy
5124
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
5125
** must be called one or more times to evaluate the statement.
5126
**
5127
** The details of the behavior of the sqlite3_step() interface depend
5128
** on whether the statement was prepared using the newer "vX" interfaces
5129
** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
5130
** [sqlite3_prepare16_v2()] or the older legacy
5131
** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
5132
** new "vX" interface is recommended for new applications but the legacy
5133
** interface will continue to be supported.
5134
**
5135
** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
5136
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
5137
** ^With the "v2" interface, any of the other [result codes] or
5138
** [extended result codes] might be returned as well.
5139
**
5140
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
5141
** database locks it needs to do its job.  ^If the statement is a [COMMIT]
5142
** or occurs outside of an explicit transaction, then you can retry the
5143
** statement.  If the statement is not a [COMMIT] and occurs within an
5144
** explicit transaction then you should rollback the transaction before
5145
** continuing.
5146
**
5147
** ^[SQLITE_DONE] means that the statement has finished executing
5148
** successfully.  sqlite3_step() should not be called again on this virtual
5149
** machine without first calling [sqlite3_reset()] to reset the virtual
5150
** machine back to its initial state.
5151
**
5152
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
5153
** is returned each time a new row of data is ready for processing by the
5154
** caller. The values may be accessed using the [column access functions].
5155
** sqlite3_step() is called again to retrieve the next row of data.
5156
**
5157
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
5158
** violation) has occurred.  sqlite3_step() should not be called again on
5159
** the VM. More information may be found by calling [sqlite3_errmsg()].
5160
** ^With the legacy interface, a more specific error code (for example,
5161
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
5162
** can be obtained by calling [sqlite3_reset()] on the
5163
** [prepared statement].  ^In the "v2" interface,
5164
** the more specific error code is returned directly by sqlite3_step().
5165
**
5166
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
5167
** Perhaps it was called on a [prepared statement] that has
5168
** already been [sqlite3_finalize | finalized] or on one that had
5169
** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
5170
** be the case that the same database connection is being used by two or
5171
** more threads at the same moment in time.
5172
**
5173
** For all versions of SQLite up to and including 3.6.23.1, a call to
5174
** [sqlite3_reset()] was required after sqlite3_step() returned anything
5175
** other than [SQLITE_ROW] before any subsequent invocation of
5176
** sqlite3_step().  Failure to reset the prepared statement using
5177
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
5178
** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1]),
5179
** sqlite3_step() began
5180
** calling [sqlite3_reset()] automatically in this circumstance rather
5181
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
5182
** break because any application that ever receives an SQLITE_MISUSE error
5183
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
5184
** can be used to restore the legacy behavior.
5185
**
5186
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
5187
** API always returns a generic error code, [SQLITE_ERROR], following any
5188
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
5189
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
5190
** specific [error codes] that better describes the error.
5191
** We admit that this is a goofy design.  The problem has been fixed
5192
** with the "v2" interface.  If you prepare all of your SQL statements
5193
** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
5194
** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
5195
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
5196
** then the more specific [error codes] are returned directly
5197
** by sqlite3_step().  The use of the "vX" interfaces is recommended.
5198
*/
5199
SQLITE_API int sqlite3_step(sqlite3_stmt*);
5200
5201
/*
5202
** CAPI3REF: Number of columns in a result set
5203
** METHOD: sqlite3_stmt
5204
**
5205
** ^The sqlite3_data_count(P) interface returns the number of columns in the
5206
** current row of the result set of [prepared statement] P.
5207
** ^If prepared statement P does not have results ready to return
5208
** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
5209
** interfaces) then sqlite3_data_count(P) returns 0.
5210
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
5211
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
5212
** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
5213
** will return non-zero if previous call to [sqlite3_step](P) returned
5214
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
5215
** where it always returns zero since each step of that multi-step
5216
** pragma returns 0 columns of data.
5217
**
5218
** See also: [sqlite3_column_count()]
5219
*/
5220
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
5221
5222
/*
5223
** CAPI3REF: Fundamental Datatypes
5224
** KEYWORDS: SQLITE_TEXT
5225
**
5226
** ^(Every value in SQLite has one of five fundamental datatypes:
5227
**
5228
** <ul>
5229
** <li> 64-bit signed integer
5230
** <li> 64-bit IEEE floating point number
5231
** <li> string
5232
** <li> BLOB
5233
** <li> NULL
5234
** </ul>)^
5235
**
5236
** These constants are codes for each of those types.
5237
**
5238
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
5239
** for a completely different meaning.  Software that links against both
5240
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
5241
** SQLITE_TEXT.
5242
*/
5243
#define SQLITE_INTEGER  1
5244
#define SQLITE_FLOAT    2
5245
#define SQLITE_BLOB     4
5246
#define SQLITE_NULL     5
5247
#ifdef SQLITE_TEXT
5248
# undef SQLITE_TEXT
5249
#else
5250
# define SQLITE_TEXT     3
5251
#endif
5252
#define SQLITE3_TEXT     3
5253
5254
/*
5255
** CAPI3REF: Result Values From A Query
5256
** KEYWORDS: {column access functions}
5257
** METHOD: sqlite3_stmt
5258
**
5259
** <b>Summary:</b>
5260
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5261
** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
5262
** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
5263
** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
5264
** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
5265
** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
5266
** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
5267
** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
5268
** [sqlite3_value|unprotected sqlite3_value] object.
5269
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5270
** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
5271
** or a UTF-8 TEXT result in bytes
5272
** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
5273
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5274
** TEXT in bytes
5275
** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
5276
** datatype of the result
5277
** </table></blockquote>
5278
**
5279
** <b>Details:</b>
5280
**
5281
** ^These routines return information about a single column of the current
5282
** result row of a query.  ^In every case the first argument is a pointer
5283
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
5284
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
5285
** and the second argument is the index of the column for which information
5286
** should be returned. ^The leftmost column of the result set has the index 0.
5287
** ^The number of columns in the result can be determined using
5288
** [sqlite3_column_count()].
5289
**
5290
** If the SQL statement does not currently point to a valid row, or if the
5291
** column index is out of range, the result is undefined.
5292
** These routines may only be called when the most recent call to
5293
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
5294
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
5295
** If any of these routines are called after [sqlite3_reset()] or
5296
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
5297
** something other than [SQLITE_ROW], the results are undefined.
5298
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
5299
** are called from a different thread while any of these routines
5300
** are pending, then the results are undefined.
5301
**
5302
** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
5303
** each return the value of a result column in a specific data format.  If
5304
** the result column is not initially in the requested format (for example,
5305
** if the query returns an integer but the sqlite3_column_text() interface
5306
** is used to extract the value) then an automatic type conversion is performed.
5307
**
5308
** ^The sqlite3_column_type() routine returns the
5309
** [SQLITE_INTEGER | datatype code] for the initial data type
5310
** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
5311
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
5312
** The return value of sqlite3_column_type() can be used to decide which
5313
** of the first six interface should be used to extract the column value.
5314
** The value returned by sqlite3_column_type() is only meaningful if no
5315
** automatic type conversions have occurred for the value in question.
5316
** After a type conversion, the result of calling sqlite3_column_type()
5317
** is undefined, though harmless.  Future
5318
** versions of SQLite may change the behavior of sqlite3_column_type()
5319
** following a type conversion.
5320
**
5321
** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
5322
** or sqlite3_column_bytes16() interfaces can be used to determine the size
5323
** of that BLOB or string.
5324
**
5325
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
5326
** routine returns the number of bytes in that BLOB or string.
5327
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
5328
** the string to UTF-8 and then returns the number of bytes.
5329
** ^If the result is a numeric value then sqlite3_column_bytes() uses
5330
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
5331
** the number of bytes in that string.
5332
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
5333
**
5334
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
5335
** routine returns the number of bytes in that BLOB or string.
5336
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
5337
** the string to UTF-16 and then returns the number of bytes.
5338
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
5339
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
5340
** the number of bytes in that string.
5341
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
5342
**
5343
** ^The values returned by [sqlite3_column_bytes()] and
5344
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
5345
** of the string.  ^For clarity: the values returned by
5346
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
5347
** bytes in the string, not the number of characters.
5348
**
5349
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
5350
** even empty strings, are always zero-terminated.  ^The return
5351
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
5352
**
5353
** ^Strings returned by sqlite3_column_text16() always have the endianness
5354
** which is native to the platform, regardless of the text encoding set
5355
** for the database.
5356
**
5357
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
5358
** [unprotected sqlite3_value] object.  In a multithreaded environment,
5359
** an unprotected sqlite3_value object may only be used safely with
5360
** [sqlite3_bind_value()] and [sqlite3_result_value()].
5361
** If the [unprotected sqlite3_value] object returned by
5362
** [sqlite3_column_value()] is used in any other way, including calls
5363
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
5364
** or [sqlite3_value_bytes()], the behavior is not threadsafe.
5365
** Hence, the sqlite3_column_value() interface
5366
** is normally only useful within the implementation of
5367
** [application-defined SQL functions] or [virtual tables], not within
5368
** top-level application code.
5369
**
5370
** These routines may attempt to convert the datatype of the result.
5371
** ^For example, if the internal representation is FLOAT and a text result
5372
** is requested, [sqlite3_snprintf()] is used internally to perform the
5373
** conversion automatically.  ^(The following table details the conversions
5374
** that are applied:
5375
**
5376
** <blockquote>
5377
** <table border="1">
5378
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
5379
**
5380
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
5381
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
5382
** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
5383
** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
5384
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
5385
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
5386
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
5387
** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
5388
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
5389
** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
5390
** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
5391
** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
5392
** <tr><td>  TEXT    <td>   BLOB    <td> No change
5393
** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
5394
** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
5395
** <tr><td>  BLOB    <td>   TEXT    <td> [CAST] to TEXT, ensure zero terminator
5396
** </table>
5397
** </blockquote>)^
5398
**
5399
** Note that when type conversions occur, pointers returned by prior
5400
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
5401
** sqlite3_column_text16() may be invalidated.
5402
** Type conversions and pointer invalidations might occur
5403
** in the following cases:
5404
**
5405
** <ul>
5406
** <li> The initial content is a BLOB and sqlite3_column_text() or
5407
**      sqlite3_column_text16() is called.  A zero-terminator might
5408
**      need to be added to the string.</li>
5409
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
5410
**      sqlite3_column_text16() is called.  The content must be converted
5411
**      to UTF-16.</li>
5412
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
5413
**      sqlite3_column_text() is called.  The content must be converted
5414
**      to UTF-8.</li>
5415
** </ul>
5416
**
5417
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
5418
** not invalidate a prior pointer, though of course the content of the buffer
5419
** that the prior pointer references will have been modified.  Other kinds
5420
** of conversion are done in place when it is possible, but sometimes they
5421
** are not possible and in those cases prior pointers are invalidated.
5422
**
5423
** The safest policy is to invoke these routines
5424
** in one of the following ways:
5425
**
5426
** <ul>
5427
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
5428
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
5429
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
5430
** </ul>
5431
**
5432
** In other words, you should call sqlite3_column_text(),
5433
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
5434
** into the desired format, then invoke sqlite3_column_bytes() or
5435
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
5436
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
5437
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
5438
** with calls to sqlite3_column_bytes().
5439
**
5440
** ^The pointers returned are valid until a type conversion occurs as
5441
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
5442
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
5443
** and BLOBs is freed automatically.  Do not pass the pointers returned
5444
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
5445
** [sqlite3_free()].
5446
**
5447
** As long as the input parameters are correct, these routines will only
5448
** fail if an out-of-memory error occurs during a format conversion.
5449
** Only the following subset of interfaces are subject to out-of-memory
5450
** errors:
5451
**
5452
** <ul>
5453
** <li> sqlite3_column_blob()
5454
** <li> sqlite3_column_text()
5455
** <li> sqlite3_column_text16()
5456
** <li> sqlite3_column_bytes()
5457
** <li> sqlite3_column_bytes16()
5458
** </ul>
5459
**
5460
** If an out-of-memory error occurs, then the return value from these
5461
** routines is the same as if the column had contained an SQL NULL value.
5462
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5463
** by invoking the [sqlite3_errcode()] immediately after the suspect
5464
** return value is obtained and before any
5465
** other SQLite interface is called on the same [database connection].
5466
*/
5467
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
5468
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
5469
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
5470
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
5471
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
5472
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
5473
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
5474
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
5475
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
5476
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
5477
5478
/*
5479
** CAPI3REF: Destroy A Prepared Statement Object
5480
** DESTRUCTOR: sqlite3_stmt
5481
**
5482
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
5483
** ^If the most recent evaluation of the statement encountered no errors
5484
** or if the statement is never been evaluated, then sqlite3_finalize() returns
5485
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
5486
** sqlite3_finalize(S) returns the appropriate [error code] or
5487
** [extended error code].
5488
**
5489
** ^The sqlite3_finalize(S) routine can be called at any point during
5490
** the life cycle of [prepared statement] S:
5491
** before statement S is ever evaluated, after
5492
** one or more calls to [sqlite3_reset()], or after any call
5493
** to [sqlite3_step()] regardless of whether or not the statement has
5494
** completed execution.
5495
**
5496
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
5497
**
5498
** The application must finalize every [prepared statement] in order to avoid
5499
** resource leaks.  It is a grievous error for the application to try to use
5500
** a prepared statement after it has been finalized.  Any use of a prepared
5501
** statement after it has been finalized can result in undefined and
5502
** undesirable behavior such as segfaults and heap corruption.
5503
*/
5504
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
5505
5506
/*
5507
** CAPI3REF: Reset A Prepared Statement Object
5508
** METHOD: sqlite3_stmt
5509
**
5510
** The sqlite3_reset() function is called to reset a [prepared statement]
5511
** object back to its initial state, ready to be re-executed.
5512
** ^Any SQL statement variables that had values bound to them using
5513
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
5514
** Use [sqlite3_clear_bindings()] to reset the bindings.
5515
**
5516
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
5517
** back to the beginning of its program.
5518
**
5519
** ^The return code from [sqlite3_reset(S)] indicates whether or not
5520
** the previous evaluation of prepared statement S completed successfully.
5521
** ^If [sqlite3_step(S)] has never before been called on S or if
5522
** [sqlite3_step(S)] has not been called since the previous call
5523
** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return
5524
** [SQLITE_OK].
5525
**
5526
** ^If the most recent call to [sqlite3_step(S)] for the
5527
** [prepared statement] S indicated an error, then
5528
** [sqlite3_reset(S)] returns an appropriate [error code].
5529
** ^The [sqlite3_reset(S)] interface might also return an [error code]
5530
** if there were no prior errors but the process of resetting
5531
** the prepared statement caused a new error. ^For example, if an
5532
** [INSERT] statement with a [RETURNING] clause is only stepped one time,
5533
** that one call to [sqlite3_step(S)] might return SQLITE_ROW but
5534
** the overall statement might still fail and the [sqlite3_reset(S)] call
5535
** might return SQLITE_BUSY if locking constraints prevent the
5536
** database change from committing.  Therefore, it is important that
5537
** applications check the return code from [sqlite3_reset(S)] even if
5538
** no prior call to [sqlite3_step(S)] indicated a problem.
5539
**
5540
** ^The [sqlite3_reset(S)] interface does not change the values
5541
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
5542
*/
5543
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
5544
5545
5546
/*
5547
** CAPI3REF: Create Or Redefine SQL Functions
5548
** KEYWORDS: {function creation routines}
5549
** METHOD: sqlite3
5550
**
5551
** ^These functions (collectively known as "function creation routines")
5552
** are used to add SQL functions or aggregates or to redefine the behavior
5553
** of existing SQL functions or aggregates. The only differences between
5554
** the three "sqlite3_create_function*" routines are the text encoding
5555
** expected for the second parameter (the name of the function being
5556
** created) and the presence or absence of a destructor callback for
5557
** the application data pointer. Function sqlite3_create_window_function()
5558
** is similar, but allows the user to supply the extra callback functions
5559
** needed by [aggregate window functions].
5560
**
5561
** ^The first parameter is the [database connection] to which the SQL
5562
** function is to be added.  ^If an application uses more than one database
5563
** connection then application-defined SQL functions must be added
5564
** to each database connection separately.
5565
**
5566
** ^The second parameter is the name of the SQL function to be created or
5567
** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
5568
** representation, exclusive of the zero-terminator.  ^Note that the name
5569
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
5570
** ^Any attempt to create a function with a longer name
5571
** will result in [SQLITE_MISUSE] being returned.
5572
**
5573
** ^The third parameter (nArg)
5574
** is the number of arguments that the SQL function or
5575
** aggregate takes. ^If this parameter is -1, then the SQL function or
5576
** aggregate may take any number of arguments between 0 and the limit
5577
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
5578
** parameter is less than -1 or greater than 127 then the behavior is
5579
** undefined.
5580
**
5581
** ^The fourth parameter, eTextRep, specifies what
5582
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
5583
** its parameters.  The application should set this parameter to
5584
** [SQLITE_UTF16LE] if the function implementation invokes
5585
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
5586
** implementation invokes [sqlite3_value_text16be()] on an input, or
5587
** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
5588
** otherwise.  ^The same SQL function may be registered multiple times using
5589
** different preferred text encodings, with different implementations for
5590
** each encoding.
5591
** ^When multiple implementations of the same function are available, SQLite
5592
** will pick the one that involves the least amount of data conversion.
5593
**
5594
** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
5595
** to signal that the function will always return the same result given
5596
** the same inputs within a single SQL statement.  Most SQL functions are
5597
** deterministic.  The built-in [random()] SQL function is an example of a
5598
** function that is not deterministic.  The SQLite query planner is able to
5599
** perform additional optimizations on deterministic functions, so use
5600
** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
5601
**
5602
** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY]
5603
** flag, which if present prevents the function from being invoked from
5604
** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions,
5605
** index expressions, or the WHERE clause of partial indexes.
5606
**
5607
** For best security, the [SQLITE_DIRECTONLY] flag is recommended for
5608
** all application-defined SQL functions that do not need to be
5609
** used inside of triggers, views, CHECK constraints, or other elements of
5610
** the database schema.  This flag is especially recommended for SQL
5611
** functions that have side effects or reveal internal application state.
5612
** Without this flag, an attacker might be able to modify the schema of
5613
** a database file to include invocations of the function with parameters
5614
** chosen by the attacker, which the application will then execute when
5615
** the database file is opened and read.
5616
**
5617
** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
5618
** function can gain access to this pointer using [sqlite3_user_data()].)^
5619
**
5620
** ^The sixth, seventh and eighth parameters passed to the three
5621
** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
5622
** pointers to C-language functions that implement the SQL function or
5623
** aggregate. ^A scalar SQL function requires an implementation of the xFunc
5624
** callback only; NULL pointers must be passed as the xStep and xFinal
5625
** parameters. ^An aggregate SQL function requires an implementation of xStep
5626
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
5627
** SQL function or aggregate, pass NULL pointers for all three function
5628
** callbacks.
5629
**
5630
** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
5631
** and xInverse) passed to sqlite3_create_window_function are pointers to
5632
** C-language callbacks that implement the new function. xStep and xFinal
5633
** must both be non-NULL. xValue and xInverse may either both be NULL, in
5634
** which case a regular aggregate function is created, or must both be
5635
** non-NULL, in which case the new function may be used as either an aggregate
5636
** or aggregate window function. More details regarding the implementation
5637
** of aggregate window functions are
5638
** [user-defined window functions|available here].
5639
**
5640
** ^(If the final parameter to sqlite3_create_function_v2() or
5641
** sqlite3_create_window_function() is not NULL, then it is the destructor for
5642
** the application data pointer. The destructor is invoked when the function
5643
** is deleted, either by being overloaded or when the database connection
5644
** closes.)^ ^The destructor is also invoked if the call to
5645
** sqlite3_create_function_v2() fails.  ^When the destructor callback is
5646
** invoked, it is passed a single argument which is a copy of the application
5647
** data pointer which was the fifth parameter to sqlite3_create_function_v2().
5648
**
5649
** ^It is permitted to register multiple implementations of the same
5650
** functions with the same name but with either differing numbers of
5651
** arguments or differing preferred text encodings.  ^SQLite will use
5652
** the implementation that most closely matches the way in which the
5653
** SQL function is used.  ^A function implementation with a non-negative
5654
** nArg parameter is a better match than a function implementation with
5655
** a negative nArg.  ^A function where the preferred text encoding
5656
** matches the database encoding is a better
5657
** match than a function where the encoding is different.
5658
** ^A function where the encoding difference is between UTF16le and UTF16be
5659
** is a closer match than a function where the encoding difference is
5660
** between UTF8 and UTF16.
5661
**
5662
** ^Built-in functions may be overloaded by new application-defined functions.
5663
**
5664
** ^An application-defined function is permitted to call other
5665
** SQLite interfaces.  However, such calls must not
5666
** close the database connection nor finalize or reset the prepared
5667
** statement in which the function is running.
5668
*/
5669
SQLITE_API int sqlite3_create_function(
5670
  sqlite3 *db,
5671
  const char *zFunctionName,
5672
  int nArg,
5673
  int eTextRep,
5674
  void *pApp,
5675
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5676
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5677
  void (*xFinal)(sqlite3_context*)
5678
);
5679
SQLITE_API int sqlite3_create_function16(
5680
  sqlite3 *db,
5681
  const void *zFunctionName,
5682
  int nArg,
5683
  int eTextRep,
5684
  void *pApp,
5685
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5686
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5687
  void (*xFinal)(sqlite3_context*)
5688
);
5689
SQLITE_API int sqlite3_create_function_v2(
5690
  sqlite3 *db,
5691
  const char *zFunctionName,
5692
  int nArg,
5693
  int eTextRep,
5694
  void *pApp,
5695
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5696
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5697
  void (*xFinal)(sqlite3_context*),
5698
  void(*xDestroy)(void*)
5699
);
5700
SQLITE_API int sqlite3_create_window_function(
5701
  sqlite3 *db,
5702
  const char *zFunctionName,
5703
  int nArg,
5704
  int eTextRep,
5705
  void *pApp,
5706
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5707
  void (*xFinal)(sqlite3_context*),
5708
  void (*xValue)(sqlite3_context*),
5709
  void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
5710
  void(*xDestroy)(void*)
5711
);
5712
5713
/*
5714
** CAPI3REF: Text Encodings
5715
**
5716
** These constant define integer codes that represent the various
5717
** text encodings supported by SQLite.
5718
*/
5719
#define SQLITE_UTF8           1    /* IMP: R-37514-35566 */
5720
#define SQLITE_UTF16LE        2    /* IMP: R-03371-37637 */
5721
#define SQLITE_UTF16BE        3    /* IMP: R-51971-34154 */
5722
#define SQLITE_UTF16          4    /* Use native byte order */
5723
#define SQLITE_ANY            5    /* Deprecated */
5724
#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
5725
5726
/*
5727
** CAPI3REF: Function Flags
5728
**
5729
** These constants may be ORed together with the
5730
** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
5731
** to [sqlite3_create_function()], [sqlite3_create_function16()], or
5732
** [sqlite3_create_function_v2()].
5733
**
5734
** <dl>
5735
** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd>
5736
** The SQLITE_DETERMINISTIC flag means that the new function always gives
5737
** the same output when the input parameters are the same.
5738
** The [abs|abs() function] is deterministic, for example, but
5739
** [randomblob|randomblob()] is not.  Functions must
5740
** be deterministic in order to be used in certain contexts such as
5741
** with the WHERE clause of [partial indexes] or in [generated columns].
5742
** SQLite might also optimize deterministic functions by factoring them
5743
** out of inner loops.
5744
** </dd>
5745
**
5746
** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
5747
** The SQLITE_DIRECTONLY flag means that the function may only be invoked
5748
** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
5749
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5750
** [expression indexes], [partial indexes], or [generated columns].
5751
** <p>
5752
** The SQLITE_DIRECTONLY flag is recommended for any
5753
** [application-defined SQL function]
5754
** that has side-effects or that could potentially leak sensitive information.
5755
** This will prevent attacks in which an application is tricked
5756
** into using a database file that has had its schema surreptitiously
5757
** modified to invoke the application-defined function in ways that are
5758
** harmful.
5759
** <p>
5760
** Some people say it is good practice to set SQLITE_DIRECTONLY on all
5761
** [application-defined SQL functions], regardless of whether or not they
5762
** are security sensitive, as doing so prevents those functions from being used
5763
** inside of the database schema, and thus ensures that the database
5764
** can be inspected and modified using generic tools (such as the [CLI])
5765
** that do not have access to the application-defined functions.
5766
** </dd>
5767
**
5768
** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
5769
** The SQLITE_INNOCUOUS flag means that the function is unlikely
5770
** to cause problems even if misused.  An innocuous function should have
5771
** no side effects and should not depend on any values other than its
5772
** input parameters. The [abs|abs() function] is an example of an
5773
** innocuous function.
5774
** The [load_extension() SQL function] is not innocuous because of its
5775
** side effects.
5776
** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not
5777
** exactly the same.  The [random|random() function] is an example of a
5778
** function that is innocuous but not deterministic.
5779
** <p>Some heightened security settings
5780
** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF])
5781
** disable the use of SQL functions inside views and triggers and in
5782
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5783
** [expression indexes], [partial indexes], and [generated columns] unless
5784
** the function is tagged with SQLITE_INNOCUOUS.  Most built-in functions
5785
** are innocuous.  Developers are advised to avoid using the
5786
** SQLITE_INNOCUOUS flag for application-defined functions unless the
5787
** function has been carefully audited and found to be free of potentially
5788
** security-adverse side-effects and information-leaks.
5789
** </dd>
5790
**
5791
** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
5792
** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call
5793
** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
5794
** This flag instructs SQLite to omit some corner-case optimizations that
5795
** might disrupt the operation of the [sqlite3_value_subtype()] function,
5796
** causing it to return zero rather than the correct subtype().
5797
** All SQL functions that invoke [sqlite3_value_subtype()] should have this
5798
** property.  If the SQLITE_SUBTYPE property is omitted, then the return
5799
** value from [sqlite3_value_subtype()] might sometimes be zero even though
5800
** a non-zero subtype was specified by the function argument expression.
5801
**
5802
** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd>
5803
** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call
5804
** [sqlite3_result_subtype()] to cause a sub-type to be associated with its
5805
** result.
5806
** Every function that invokes [sqlite3_result_subtype()] should have this
5807
** property.  If it does not, then the call to [sqlite3_result_subtype()]
5808
** might become a no-op if the function is used as term in an
5809
** [expression index].  On the other hand, SQL functions that never invoke
5810
** [sqlite3_result_subtype()] should avoid setting this property, as the
5811
** purpose of this property is to disable certain optimizations that are
5812
** incompatible with subtypes.
5813
**
5814
** [[SQLITE_SELFORDER1]] <dt>SQLITE_SELFORDER1</dt><dd>
5815
** The SQLITE_SELFORDER1 flag indicates that the function is an aggregate
5816
** that internally orders the values provided to the first argument.  The
5817
** ordered-set aggregate SQL notation with a single ORDER BY term can be
5818
** used to invoke this function.  If the ordered-set aggregate notation is
5819
** used on a function that lacks this flag, then an error is raised. Note
5820
** that the ordered-set aggregate syntax is only available if SQLite is
5821
** built using the -DSQLITE_ENABLE_ORDERED_SET_AGGREGATES compile-time option.
5822
** </dd>
5823
** </dl>
5824
*/
5825
#define SQLITE_DETERMINISTIC    0x000000800
5826
#define SQLITE_DIRECTONLY       0x000080000
5827
#define SQLITE_SUBTYPE          0x000100000
5828
#define SQLITE_INNOCUOUS        0x000200000
5829
#define SQLITE_RESULT_SUBTYPE   0x001000000
5830
#define SQLITE_SELFORDER1       0x002000000
5831
5832
/*
5833
** CAPI3REF: Deprecated Functions
5834
** DEPRECATED
5835
**
5836
** These functions are [deprecated].  In order to maintain
5837
** backwards compatibility with older code, these functions continue
5838
** to be supported.  However, new applications should avoid
5839
** the use of these functions.  To encourage programmers to avoid
5840
** these functions, we will not explain what they do.
5841
*/
5842
#ifndef SQLITE_OMIT_DEPRECATED
5843
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
5844
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
5845
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
5846
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
5847
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
5848
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
5849
                      void*,sqlite3_int64);
5850
#endif
5851
5852
/*
5853
** CAPI3REF: Obtaining SQL Values
5854
** METHOD: sqlite3_value
5855
**
5856
** <b>Summary:</b>
5857
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5858
** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
5859
** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
5860
** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
5861
** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
5862
** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
5863
** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
5864
** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
5865
** the native byteorder
5866
** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
5867
** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
5868
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5869
** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
5870
** or a UTF-8 TEXT in bytes
5871
** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
5872
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5873
** TEXT in bytes
5874
** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
5875
** datatype of the value
5876
** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
5877
** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
5878
** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
5879
** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
5880
** against a virtual table.
5881
** <tr><td><b>sqlite3_value_frombind&nbsp;&nbsp;</b>
5882
** <td>&rarr;&nbsp;&nbsp;<td>True if value originated from a [bound parameter]
5883
** </table></blockquote>
5884
**
5885
** <b>Details:</b>
5886
**
5887
** These routines extract type, size, and content information from
5888
** [protected sqlite3_value] objects.  Protected sqlite3_value objects
5889
** are used to pass parameter information into the functions that
5890
** implement [application-defined SQL functions] and [virtual tables].
5891
**
5892
** These routines work only with [protected sqlite3_value] objects.
5893
** Any attempt to use these routines on an [unprotected sqlite3_value]
5894
** is not threadsafe.
5895
**
5896
** ^These routines work just like the corresponding [column access functions]
5897
** except that these routines take a single [protected sqlite3_value] object
5898
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
5899
**
5900
** ^The sqlite3_value_text16() interface extracts a UTF-16 string
5901
** in the native byte-order of the host machine.  ^The
5902
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
5903
** extract UTF-16 strings as big-endian and little-endian respectively.
5904
**
5905
** ^If [sqlite3_value] object V was initialized
5906
** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
5907
** and if X and Y are strings that compare equal according to strcmp(X,Y),
5908
** then sqlite3_value_pointer(V,Y) will return the pointer P.  ^Otherwise,
5909
** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
5910
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5911
**
5912
** ^(The sqlite3_value_type(V) interface returns the
5913
** [SQLITE_INTEGER | datatype code] for the initial datatype of the
5914
** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
5915
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
5916
** Other interfaces might change the datatype for an sqlite3_value object.
5917
** For example, if the datatype is initially SQLITE_INTEGER and
5918
** sqlite3_value_text(V) is called to extract a text value for that
5919
** integer, then subsequent calls to sqlite3_value_type(V) might return
5920
** SQLITE_TEXT.  Whether or not a persistent internal datatype conversion
5921
** occurs is undefined and may change from one release of SQLite to the next.
5922
**
5923
** ^(The sqlite3_value_numeric_type() interface attempts to apply
5924
** numeric affinity to the value.  This means that an attempt is
5925
** made to convert the value to an integer or floating point.  If
5926
** such a conversion is possible without loss of information (in other
5927
** words, if the value is a string that looks like a number)
5928
** then the conversion is performed.  Otherwise no conversion occurs.
5929
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
5930
**
5931
** ^Within the [xUpdate] method of a [virtual table], the
5932
** sqlite3_value_nochange(X) interface returns true if and only if
5933
** the column corresponding to X is unchanged by the UPDATE operation
5934
** that the xUpdate method call was invoked to implement and if
5935
** and the prior [xColumn] method call that was invoked to extracted
5936
** the value for that column returned without setting a result (probably
5937
** because it queried [sqlite3_vtab_nochange()] and found that the column
5938
** was unchanging).  ^Within an [xUpdate] method, any value for which
5939
** sqlite3_value_nochange(X) is true will in all other respects appear
5940
** to be a NULL value.  If sqlite3_value_nochange(X) is invoked anywhere other
5941
** than within an [xUpdate] method call for an UPDATE statement, then
5942
** the return value is arbitrary and meaningless.
5943
**
5944
** ^The sqlite3_value_frombind(X) interface returns non-zero if the
5945
** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
5946
** interfaces.  ^If X comes from an SQL literal value, or a table column,
5947
** or an expression, then sqlite3_value_frombind(X) returns zero.
5948
**
5949
** Please pay particular attention to the fact that the pointer returned
5950
** from [sqlite3_value_blob()], [sqlite3_value_text()], or
5951
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
5952
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
5953
** or [sqlite3_value_text16()].
5954
**
5955
** These routines must be called from the same thread as
5956
** the SQL function that supplied the [sqlite3_value*] parameters.
5957
**
5958
** As long as the input parameter is correct, these routines can only
5959
** fail if an out-of-memory error occurs during a format conversion.
5960
** Only the following subset of interfaces are subject to out-of-memory
5961
** errors:
5962
**
5963
** <ul>
5964
** <li> sqlite3_value_blob()
5965
** <li> sqlite3_value_text()
5966
** <li> sqlite3_value_text16()
5967
** <li> sqlite3_value_text16le()
5968
** <li> sqlite3_value_text16be()
5969
** <li> sqlite3_value_bytes()
5970
** <li> sqlite3_value_bytes16()
5971
** </ul>
5972
**
5973
** If an out-of-memory error occurs, then the return value from these
5974
** routines is the same as if the column had contained an SQL NULL value.
5975
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5976
** by invoking the [sqlite3_errcode()] immediately after the suspect
5977
** return value is obtained and before any
5978
** other SQLite interface is called on the same [database connection].
5979
*/
5980
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
5981
SQLITE_API double sqlite3_value_double(sqlite3_value*);
5982
SQLITE_API int sqlite3_value_int(sqlite3_value*);
5983
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
5984
SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
5985
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
5986
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
5987
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
5988
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
5989
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
5990
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
5991
SQLITE_API int sqlite3_value_type(sqlite3_value*);
5992
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
5993
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
5994
SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
5995
5996
/*
5997
** CAPI3REF: Report the internal text encoding state of an sqlite3_value object
5998
** METHOD: sqlite3_value
5999
**
6000
** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8],
6001
** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding
6002
** of the value X, assuming that X has type TEXT.)^  If sqlite3_value_type(X)
6003
** returns something other than SQLITE_TEXT, then the return value from
6004
** sqlite3_value_encoding(X) is meaningless.  ^Calls to
6005
** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)],
6006
** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or
6007
** [sqlite3_value_bytes16(X)] might change the encoding of the value X and
6008
** thus change the return from subsequent calls to sqlite3_value_encoding(X).
6009
**
6010
** This routine is intended for used by applications that test and validate
6011
** the SQLite implementation.  This routine is inquiring about the opaque
6012
** internal state of an [sqlite3_value] object.  Ordinary applications should
6013
** not need to know what the internal state of an sqlite3_value object is and
6014
** hence should not need to use this interface.
6015
*/
6016
SQLITE_API int sqlite3_value_encoding(sqlite3_value*);
6017
6018
/*
6019
** CAPI3REF: Finding The Subtype Of SQL Values
6020
** METHOD: sqlite3_value
6021
**
6022
** The sqlite3_value_subtype(V) function returns the subtype for
6023
** an [application-defined SQL function] argument V.  The subtype
6024
** information can be used to pass a limited amount of context from
6025
** one SQL function to another.  Use the [sqlite3_result_subtype()]
6026
** routine to set the subtype for the return value of an SQL function.
6027
**
6028
** Every [application-defined SQL function] that invokes this interface
6029
** should include the [SQLITE_SUBTYPE] property in the text
6030
** encoding argument when the function is [sqlite3_create_function|registered].
6031
** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype()
6032
** might return zero instead of the upstream subtype in some corner cases.
6033
*/
6034
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
6035
6036
/*
6037
** CAPI3REF: Copy And Free SQL Values
6038
** METHOD: sqlite3_value
6039
**
6040
** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
6041
** object V and returns a pointer to that copy.  ^The [sqlite3_value] returned
6042
** is a [protected sqlite3_value] object even if the input is not.
6043
** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
6044
** memory allocation fails. ^If V is a [pointer value], then the result
6045
** of sqlite3_value_dup(V) is a NULL value.
6046
**
6047
** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
6048
** previously obtained from [sqlite3_value_dup()].  ^If V is a NULL pointer
6049
** then sqlite3_value_free(V) is a harmless no-op.
6050
*/
6051
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
6052
SQLITE_API void sqlite3_value_free(sqlite3_value*);
6053
6054
/*
6055
** CAPI3REF: Obtain Aggregate Function Context
6056
** METHOD: sqlite3_context
6057
**
6058
** Implementations of aggregate SQL functions use this
6059
** routine to allocate memory for storing their state.
6060
**
6061
** ^The first time the sqlite3_aggregate_context(C,N) routine is called
6062
** for a particular aggregate function, SQLite allocates
6063
** N bytes of memory, zeroes out that memory, and returns a pointer
6064
** to the new memory. ^On second and subsequent calls to
6065
** sqlite3_aggregate_context() for the same aggregate function instance,
6066
** the same buffer is returned.  Sqlite3_aggregate_context() is normally
6067
** called once for each invocation of the xStep callback and then one
6068
** last time when the xFinal callback is invoked.  ^(When no rows match
6069
** an aggregate query, the xStep() callback of the aggregate function
6070
** implementation is never called and xFinal() is called exactly once.
6071
** In those cases, sqlite3_aggregate_context() might be called for the
6072
** first time from within xFinal().)^
6073
**
6074
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
6075
** when first called if N is less than or equal to zero or if a memory
6076
** allocation error occurs.
6077
**
6078
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
6079
** determined by the N parameter on the first successful call.  Changing the
6080
** value of N in any subsequent call to sqlite3_aggregate_context() within
6081
** the same aggregate function instance will not resize the memory
6082
** allocation.)^  Within the xFinal callback, it is customary to set
6083
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
6084
** pointless memory allocations occur.
6085
**
6086
** ^SQLite automatically frees the memory allocated by
6087
** sqlite3_aggregate_context() when the aggregate query concludes.
6088
**
6089
** The first parameter must be a copy of the
6090
** [sqlite3_context | SQL function context] that is the first parameter
6091
** to the xStep or xFinal callback routine that implements the aggregate
6092
** function.
6093
**
6094
** This routine must be called from the same thread in which
6095
** the aggregate SQL function is running.
6096
*/
6097
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
6098
6099
/*
6100
** CAPI3REF: User Data For Functions
6101
** METHOD: sqlite3_context
6102
**
6103
** ^The sqlite3_user_data() interface returns a copy of
6104
** the pointer that was the pUserData parameter (the 5th parameter)
6105
** of the [sqlite3_create_function()]
6106
** and [sqlite3_create_function16()] routines that originally
6107
** registered the application defined function.
6108
**
6109
** This routine must be called from the same thread in which
6110
** the application-defined function is running.
6111
*/
6112
SQLITE_API void *sqlite3_user_data(sqlite3_context*);
6113
6114
/*
6115
** CAPI3REF: Database Connection For Functions
6116
** METHOD: sqlite3_context
6117
**
6118
** ^The sqlite3_context_db_handle() interface returns a copy of
6119
** the pointer to the [database connection] (the 1st parameter)
6120
** of the [sqlite3_create_function()]
6121
** and [sqlite3_create_function16()] routines that originally
6122
** registered the application defined function.
6123
*/
6124
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
6125
6126
/*
6127
** CAPI3REF: Function Auxiliary Data
6128
** METHOD: sqlite3_context
6129
**
6130
** These functions may be used by (non-aggregate) SQL functions to
6131
** associate auxiliary data with argument values. If the same argument
6132
** value is passed to multiple invocations of the same SQL function during
6133
** query execution, under some circumstances the associated auxiliary data
6134
** might be preserved.  An example of where this might be useful is in a
6135
** regular-expression matching function. The compiled version of the regular
6136
** expression can be stored as auxiliary data associated with the pattern string.
6137
** Then as long as the pattern string remains the same,
6138
** the compiled regular expression can be reused on multiple
6139
** invocations of the same function.
6140
**
6141
** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the auxiliary data
6142
** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
6143
** value to the application-defined function.  ^N is zero for the left-most
6144
** function argument.  ^If there is no auxiliary data
6145
** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
6146
** returns a NULL pointer.
6147
**
6148
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as auxiliary data for the
6149
** N-th argument of the application-defined function.  ^Subsequent
6150
** calls to sqlite3_get_auxdata(C,N) return P from the most recent
6151
** sqlite3_set_auxdata(C,N,P,X) call if the auxiliary data is still valid or
6152
** NULL if the auxiliary data has been discarded.
6153
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
6154
** SQLite will invoke the destructor function X with parameter P exactly
6155
** once, when the auxiliary data is discarded.
6156
** SQLite is free to discard the auxiliary data at any time, including: <ul>
6157
** <li> ^(when the corresponding function parameter changes)^, or
6158
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
6159
**      SQL statement)^, or
6160
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
6161
**       parameter)^, or
6162
** <li> ^(during the original sqlite3_set_auxdata() call when a memory
6163
**      allocation error occurs.)^
6164
** <li> ^(during the original sqlite3_set_auxdata() call if the function
6165
**      is evaluated during query planning instead of during query execution,
6166
**      as sometimes happens with [SQLITE_ENABLE_STAT4].)^ </ul>
6167
**
6168
** Note the last two bullets in particular.  The destructor X in
6169
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
6170
** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
6171
** should be called near the end of the function implementation and the
6172
** function implementation should not make any use of P after
6173
** sqlite3_set_auxdata() has been called.  Furthermore, a call to
6174
** sqlite3_get_auxdata() that occurs immediately after a corresponding call
6175
** to sqlite3_set_auxdata() might still return NULL if an out-of-memory
6176
** condition occurred during the sqlite3_set_auxdata() call or if the
6177
** function is being evaluated during query planning rather than during
6178
** query execution.
6179
**
6180
** ^(In practice, auxiliary data is preserved between function calls for
6181
** function parameters that are compile-time constants, including literal
6182
** values and [parameters] and expressions composed from the same.)^
6183
**
6184
** The value of the N parameter to these interfaces should be non-negative.
6185
** Future enhancements may make use of negative N values to define new
6186
** kinds of function caching behavior.
6187
**
6188
** These routines must be called from the same thread in which
6189
** the SQL function is running.
6190
**
6191
** See also: [sqlite3_get_clientdata()] and [sqlite3_set_clientdata()].
6192
*/
6193
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
6194
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
6195
6196
/*
6197
** CAPI3REF: Database Connection Client Data
6198
** METHOD: sqlite3
6199
**
6200
** These functions are used to associate one or more named pointers
6201
** with a [database connection].
6202
** A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P
6203
** to be attached to [database connection] D using name N.  Subsequent
6204
** calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P
6205
** or a NULL pointer if there were no prior calls to
6206
** sqlite3_set_clientdata() with the same values of D and N.
6207
** Names are compared using strcmp() and are thus case sensitive.
6208
**
6209
** If P and X are both non-NULL, then the destructor X is invoked with
6210
** argument P on the first of the following occurrences:
6211
** <ul>
6212
** <li> An out-of-memory error occurs during the call to
6213
**      sqlite3_set_clientdata() which attempts to register pointer P.
6214
** <li> A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made
6215
**      with the same D and N parameters.
6216
** <li> The database connection closes.  SQLite does not make any guarantees
6217
**      about the order in which destructors are called, only that all
6218
**      destructors will be called exactly once at some point during the
6219
**      database connection closing process.
6220
** </ul>
6221
**
6222
** SQLite does not do anything with client data other than invoke
6223
** destructors on the client data at the appropriate time.  The intended
6224
** use for client data is to provide a mechanism for wrapper libraries
6225
** to store additional information about an SQLite database connection.
6226
**
6227
** There is no limit (other than available memory) on the number of different
6228
** client data pointers (with different names) that can be attached to a
6229
** single database connection.  However, the implementation is optimized
6230
** for the case of having only one or two different client data names.
6231
** Applications and wrapper libraries are discouraged from using more than
6232
** one client data name each.
6233
**
6234
** There is no way to enumerate the client data pointers
6235
** associated with a database connection.  The N parameter can be thought
6236
** of as a secret key such that only code that knows the secret key is able
6237
** to access the associated data.
6238
**
6239
** Security Warning:  These interfaces should not be exposed in scripting
6240
** languages or in other circumstances where it might be possible for an
6241
** attacker to invoke them.  Any agent that can invoke these interfaces
6242
** can probably also take control of the process.
6243
**
6244
** Database connection client data is only available for SQLite
6245
** version 3.44.0 ([dateof:3.44.0]) and later.
6246
**
6247
** See also: [sqlite3_set_auxdata()] and [sqlite3_get_auxdata()].
6248
*/
6249
SQLITE_API void *sqlite3_get_clientdata(sqlite3*,const char*);
6250
SQLITE_API int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*));
6251
6252
/*
6253
** CAPI3REF: Constants Defining Special Destructor Behavior
6254
**
6255
** These are special values for the destructor that is passed in as the
6256
** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
6257
** argument is SQLITE_STATIC, it means that the content pointer is constant
6258
** and will never change.  It does not need to be destroyed.  ^The
6259
** SQLITE_TRANSIENT value means that the content will likely change in
6260
** the near future and that SQLite should make its own private copy of
6261
** the content before returning.
6262
**
6263
** The typedef is necessary to work around problems in certain
6264
** C++ compilers.
6265
*/
6266
typedef void (*sqlite3_destructor_type)(void*);
6267
0
#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
6268
#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
6269
6270
/*
6271
** CAPI3REF: Setting The Result Of An SQL Function
6272
** METHOD: sqlite3_context
6273
**
6274
** These routines are used by the xFunc or xFinal callbacks that
6275
** implement SQL functions and aggregates.  See
6276
** [sqlite3_create_function()] and [sqlite3_create_function16()]
6277
** for additional information.
6278
**
6279
** These functions work very much like the [parameter binding] family of
6280
** functions used to bind values to host parameters in prepared statements.
6281
** Refer to the [SQL parameter] documentation for additional information.
6282
**
6283
** ^The sqlite3_result_blob() interface sets the result from
6284
** an application-defined function to be the BLOB whose content is pointed
6285
** to by the second parameter and which is N bytes long where N is the
6286
** third parameter.
6287
**
6288
** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
6289
** interfaces set the result of the application-defined function to be
6290
** a BLOB containing all zero bytes and N bytes in size.
6291
**
6292
** ^The sqlite3_result_double() interface sets the result from
6293
** an application-defined function to be a floating point value specified
6294
** by its 2nd argument.
6295
**
6296
** ^The sqlite3_result_error() and sqlite3_result_error16() functions
6297
** cause the implemented SQL function to throw an exception.
6298
** ^SQLite uses the string pointed to by the
6299
** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
6300
** as the text of an error message.  ^SQLite interprets the error
6301
** message string from sqlite3_result_error() as UTF-8. ^SQLite
6302
** interprets the string from sqlite3_result_error16() as UTF-16 using
6303
** the same [byte-order determination rules] as [sqlite3_bind_text16()].
6304
** ^If the third parameter to sqlite3_result_error()
6305
** or sqlite3_result_error16() is negative then SQLite takes as the error
6306
** message all text up through the first zero character.
6307
** ^If the third parameter to sqlite3_result_error() or
6308
** sqlite3_result_error16() is non-negative then SQLite takes that many
6309
** bytes (not characters) from the 2nd parameter as the error message.
6310
** ^The sqlite3_result_error() and sqlite3_result_error16()
6311
** routines make a private copy of the error message text before
6312
** they return.  Hence, the calling function can deallocate or
6313
** modify the text after they return without harm.
6314
** ^The sqlite3_result_error_code() function changes the error code
6315
** returned by SQLite as a result of an error in a function.  ^By default,
6316
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
6317
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
6318
**
6319
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
6320
** error indicating that a string or BLOB is too long to represent.
6321
**
6322
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
6323
** error indicating that a memory allocation failed.
6324
**
6325
** ^The sqlite3_result_int() interface sets the return value
6326
** of the application-defined function to be the 32-bit signed integer
6327
** value given in the 2nd argument.
6328
** ^The sqlite3_result_int64() interface sets the return value
6329
** of the application-defined function to be the 64-bit signed integer
6330
** value given in the 2nd argument.
6331
**
6332
** ^The sqlite3_result_null() interface sets the return value
6333
** of the application-defined function to be NULL.
6334
**
6335
** ^The sqlite3_result_text(), sqlite3_result_text16(),
6336
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
6337
** set the return value of the application-defined function to be
6338
** a text string which is represented as UTF-8, UTF-16 native byte order,
6339
** UTF-16 little endian, or UTF-16 big endian, respectively.
6340
** ^The sqlite3_result_text64() interface sets the return value of an
6341
** application-defined function to be a text string in an encoding
6342
** specified by the fifth (and last) parameter, which must be one
6343
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
6344
** ^SQLite takes the text result from the application from
6345
** the 2nd parameter of the sqlite3_result_text* interfaces.
6346
** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces
6347
** other than sqlite3_result_text64() is negative, then SQLite computes
6348
** the string length itself by searching the 2nd parameter for the first
6349
** zero character.
6350
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
6351
** is non-negative, then as many bytes (not characters) of the text
6352
** pointed to by the 2nd parameter are taken as the application-defined
6353
** function result.  If the 3rd parameter is non-negative, then it
6354
** must be the byte offset into the string where the NUL terminator would
6355
** appear if the string were NUL terminated.  If any NUL characters occur
6356
** in the string at a byte offset that is less than the value of the 3rd
6357
** parameter, then the resulting string will contain embedded NULs and the
6358
** result of expressions operating on strings with embedded NULs is undefined.
6359
** ^If the 4th parameter to the sqlite3_result_text* interfaces
6360
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
6361
** function as the destructor on the text or BLOB result when it has
6362
** finished using that result.
6363
** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
6364
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
6365
** assumes that the text or BLOB result is in constant space and does not
6366
** copy the content of the parameter nor call a destructor on the content
6367
** when it has finished using that result.
6368
** ^If the 4th parameter to the sqlite3_result_text* interfaces
6369
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
6370
** then SQLite makes a copy of the result into space obtained
6371
** from [sqlite3_malloc()] before it returns.
6372
**
6373
** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and
6374
** sqlite3_result_text16be() routines, and for sqlite3_result_text64()
6375
** when the encoding is not UTF8, if the input UTF16 begins with a
6376
** byte-order mark (BOM, U+FEFF) then the BOM is removed from the
6377
** string and the rest of the string is interpreted according to the
6378
** byte-order specified by the BOM.  ^The byte-order specified by
6379
** the BOM at the beginning of the text overrides the byte-order
6380
** specified by the interface procedure.  ^So, for example, if
6381
** sqlite3_result_text16le() is invoked with text that begins
6382
** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the
6383
** first two bytes of input are skipped and the remaining input
6384
** is interpreted as UTF16BE text.
6385
**
6386
** ^For UTF16 input text to the sqlite3_result_text16(),
6387
** sqlite3_result_text16be(), sqlite3_result_text16le(), and
6388
** sqlite3_result_text64() routines, if the text contains invalid
6389
** UTF16 characters, the invalid characters might be converted
6390
** into the unicode replacement character, U+FFFD.
6391
**
6392
** ^The sqlite3_result_value() interface sets the result of
6393
** the application-defined function to be a copy of the
6394
** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
6395
** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
6396
** so that the [sqlite3_value] specified in the parameter may change or
6397
** be deallocated after sqlite3_result_value() returns without harm.
6398
** ^A [protected sqlite3_value] object may always be used where an
6399
** [unprotected sqlite3_value] object is required, so either
6400
** kind of [sqlite3_value] object can be used with this interface.
6401
**
6402
** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
6403
** SQL NULL value, just like [sqlite3_result_null(C)], except that it
6404
** also associates the host-language pointer P or type T with that
6405
** NULL value such that the pointer can be retrieved within an
6406
** [application-defined SQL function] using [sqlite3_value_pointer()].
6407
** ^If the D parameter is not NULL, then it is a pointer to a destructor
6408
** for the P parameter.  ^SQLite invokes D with P as its only argument
6409
** when SQLite is finished with P.  The T parameter should be a static
6410
** string and preferably a string literal. The sqlite3_result_pointer()
6411
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
6412
**
6413
** If these routines are called from within a different thread
6414
** than the one containing the application-defined function that received
6415
** the [sqlite3_context] pointer, the results are undefined.
6416
*/
6417
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
6418
SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
6419
                           sqlite3_uint64,void(*)(void*));
6420
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
6421
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
6422
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
6423
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
6424
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
6425
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
6426
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
6427
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
6428
SQLITE_API void sqlite3_result_null(sqlite3_context*);
6429
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
6430
SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
6431
                           void(*)(void*), unsigned char encoding);
6432
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
6433
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
6434
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
6435
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
6436
SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
6437
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
6438
SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
6439
6440
6441
/*
6442
** CAPI3REF: Setting The Subtype Of An SQL Function
6443
** METHOD: sqlite3_context
6444
**
6445
** The sqlite3_result_subtype(C,T) function causes the subtype of
6446
** the result from the [application-defined SQL function] with
6447
** [sqlite3_context] C to be the value T.  Only the lower 8 bits
6448
** of the subtype T are preserved in current versions of SQLite;
6449
** higher order bits are discarded.
6450
** The number of subtype bytes preserved by SQLite might increase
6451
** in future releases of SQLite.
6452
**
6453
** Every [application-defined SQL function] that invokes this interface
6454
** should include the [SQLITE_RESULT_SUBTYPE] property in its
6455
** text encoding argument when the SQL function is
6456
** [sqlite3_create_function|registered].  If the [SQLITE_RESULT_SUBTYPE]
6457
** property is omitted from the function that invokes sqlite3_result_subtype(),
6458
** then in some cases the sqlite3_result_subtype() might fail to set
6459
** the result subtype.
6460
**
6461
** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any
6462
** SQL function that invokes the sqlite3_result_subtype() interface
6463
** and that does not have the SQLITE_RESULT_SUBTYPE property will raise
6464
** an error.  Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1
6465
** by default.
6466
*/
6467
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
6468
6469
/*
6470
** CAPI3REF: Define New Collating Sequences
6471
** METHOD: sqlite3
6472
**
6473
** ^These functions add, remove, or modify a [collation] associated
6474
** with the [database connection] specified as the first argument.
6475
**
6476
** ^The name of the collation is a UTF-8 string
6477
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
6478
** and a UTF-16 string in native byte order for sqlite3_create_collation16().
6479
** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
6480
** considered to be the same name.
6481
**
6482
** ^(The third argument (eTextRep) must be one of the constants:
6483
** <ul>
6484
** <li> [SQLITE_UTF8],
6485
** <li> [SQLITE_UTF16LE],
6486
** <li> [SQLITE_UTF16BE],
6487
** <li> [SQLITE_UTF16], or
6488
** <li> [SQLITE_UTF16_ALIGNED].
6489
** </ul>)^
6490
** ^The eTextRep argument determines the encoding of strings passed
6491
** to the collating function callback, xCompare.
6492
** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
6493
** force strings to be UTF16 with native byte order.
6494
** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
6495
** on an even byte address.
6496
**
6497
** ^The fourth argument, pArg, is an application data pointer that is passed
6498
** through as the first argument to the collating function callback.
6499
**
6500
** ^The fifth argument, xCompare, is a pointer to the collating function.
6501
** ^Multiple collating functions can be registered using the same name but
6502
** with different eTextRep parameters and SQLite will use whichever
6503
** function requires the least amount of data transformation.
6504
** ^If the xCompare argument is NULL then the collating function is
6505
** deleted.  ^When all collating functions having the same name are deleted,
6506
** that collation is no longer usable.
6507
**
6508
** ^The collating function callback is invoked with a copy of the pArg
6509
** application data pointer and with two strings in the encoding specified
6510
** by the eTextRep argument.  The two integer parameters to the collating
6511
** function callback are the length of the two strings, in bytes. The collating
6512
** function must return an integer that is negative, zero, or positive
6513
** if the first string is less than, equal to, or greater than the second,
6514
** respectively.  A collating function must always return the same answer
6515
** given the same inputs.  If two or more collating functions are registered
6516
** to the same collation name (using different eTextRep values) then all
6517
** must give an equivalent answer when invoked with equivalent strings.
6518
** The collating function must obey the following properties for all
6519
** strings A, B, and C:
6520
**
6521
** <ol>
6522
** <li> If A==B then B==A.
6523
** <li> If A==B and B==C then A==C.
6524
** <li> If A&lt;B THEN B&gt;A.
6525
** <li> If A&lt;B and B&lt;C then A&lt;C.
6526
** </ol>
6527
**
6528
** If a collating function fails any of the above constraints and that
6529
** collating function is registered and used, then the behavior of SQLite
6530
** is undefined.
6531
**
6532
** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
6533
** with the addition that the xDestroy callback is invoked on pArg when
6534
** the collating function is deleted.
6535
** ^Collating functions are deleted when they are overridden by later
6536
** calls to the collation creation functions or when the
6537
** [database connection] is closed using [sqlite3_close()].
6538
**
6539
** ^The xDestroy callback is <u>not</u> called if the
6540
** sqlite3_create_collation_v2() function fails.  Applications that invoke
6541
** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
6542
** check the return code and dispose of the application data pointer
6543
** themselves rather than expecting SQLite to deal with it for them.
6544
** This is different from every other SQLite interface.  The inconsistency
6545
** is unfortunate but cannot be changed without breaking backwards
6546
** compatibility.
6547
**
6548
** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
6549
*/
6550
SQLITE_API int sqlite3_create_collation(
6551
  sqlite3*,
6552
  const char *zName,
6553
  int eTextRep,
6554
  void *pArg,
6555
  int(*xCompare)(void*,int,const void*,int,const void*)
6556
);
6557
SQLITE_API int sqlite3_create_collation_v2(
6558
  sqlite3*,
6559
  const char *zName,
6560
  int eTextRep,
6561
  void *pArg,
6562
  int(*xCompare)(void*,int,const void*,int,const void*),
6563
  void(*xDestroy)(void*)
6564
);
6565
SQLITE_API int sqlite3_create_collation16(
6566
  sqlite3*,
6567
  const void *zName,
6568
  int eTextRep,
6569
  void *pArg,
6570
  int(*xCompare)(void*,int,const void*,int,const void*)
6571
);
6572
6573
/*
6574
** CAPI3REF: Collation Needed Callbacks
6575
** METHOD: sqlite3
6576
**
6577
** ^To avoid having to register all collation sequences before a database
6578
** can be used, a single callback function may be registered with the
6579
** [database connection] to be invoked whenever an undefined collation
6580
** sequence is required.
6581
**
6582
** ^If the function is registered using the sqlite3_collation_needed() API,
6583
** then it is passed the names of undefined collation sequences as strings
6584
** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
6585
** the names are passed as UTF-16 in machine native byte order.
6586
** ^A call to either function replaces the existing collation-needed callback.
6587
**
6588
** ^(When the callback is invoked, the first argument passed is a copy
6589
** of the second argument to sqlite3_collation_needed() or
6590
** sqlite3_collation_needed16().  The second argument is the database
6591
** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
6592
** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
6593
** sequence function required.  The fourth parameter is the name of the
6594
** required collation sequence.)^
6595
**
6596
** The callback function should register the desired collation using
6597
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
6598
** [sqlite3_create_collation_v2()].
6599
*/
6600
SQLITE_API int sqlite3_collation_needed(
6601
  sqlite3*,
6602
  void*,
6603
  void(*)(void*,sqlite3*,int eTextRep,const char*)
6604
);
6605
SQLITE_API int sqlite3_collation_needed16(
6606
  sqlite3*,
6607
  void*,
6608
  void(*)(void*,sqlite3*,int eTextRep,const void*)
6609
);
6610
6611
#ifdef SQLITE_ENABLE_CEROD
6612
/*
6613
** Specify the activation key for a CEROD database.  Unless
6614
** activated, none of the CEROD routines will work.
6615
*/
6616
SQLITE_API void sqlite3_activate_cerod(
6617
  const char *zPassPhrase        /* Activation phrase */
6618
);
6619
#endif
6620
6621
/*
6622
** CAPI3REF: Suspend Execution For A Short Time
6623
**
6624
** The sqlite3_sleep() function causes the current thread to suspend execution
6625
** for at least a number of milliseconds specified in its parameter.
6626
**
6627
** If the operating system does not support sleep requests with
6628
** millisecond time resolution, then the time will be rounded up to
6629
** the nearest second. The number of milliseconds of sleep actually
6630
** requested from the operating system is returned.
6631
**
6632
** ^SQLite implements this interface by calling the xSleep()
6633
** method of the default [sqlite3_vfs] object.  If the xSleep() method
6634
** of the default VFS is not implemented correctly, or not implemented at
6635
** all, then the behavior of sqlite3_sleep() may deviate from the description
6636
** in the previous paragraphs.
6637
**
6638
** If a negative argument is passed to sqlite3_sleep() the results vary by
6639
** VFS and operating system.  Some system treat a negative argument as an
6640
** instruction to sleep forever.  Others understand it to mean do not sleep
6641
** at all. ^In SQLite version 3.42.0 and later, a negative
6642
** argument passed into sqlite3_sleep() is changed to zero before it is relayed
6643
** down into the xSleep method of the VFS.
6644
*/
6645
SQLITE_API int sqlite3_sleep(int);
6646
6647
/*
6648
** CAPI3REF: Name Of The Folder Holding Temporary Files
6649
**
6650
** ^(If this global variable is made to point to a string which is
6651
** the name of a folder (a.k.a. directory), then all temporary files
6652
** created by SQLite when using a built-in [sqlite3_vfs | VFS]
6653
** will be placed in that directory.)^  ^If this variable
6654
** is a NULL pointer, then SQLite performs a search for an appropriate
6655
** temporary file directory.
6656
**
6657
** Applications are strongly discouraged from using this global variable.
6658
** It is required to set a temporary folder on Windows Runtime (WinRT).
6659
** But for all other platforms, it is highly recommended that applications
6660
** neither read nor write this variable.  This global variable is a relic
6661
** that exists for backwards compatibility of legacy applications and should
6662
** be avoided in new projects.
6663
**
6664
** It is not safe to read or modify this variable in more than one
6665
** thread at a time.  It is not safe to read or modify this variable
6666
** if a [database connection] is being used at the same time in a separate
6667
** thread.
6668
** It is intended that this variable be set once
6669
** as part of process initialization and before any SQLite interface
6670
** routines have been called and that this variable remain unchanged
6671
** thereafter.
6672
**
6673
** ^The [temp_store_directory pragma] may modify this variable and cause
6674
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
6675
** the [temp_store_directory pragma] always assumes that any string
6676
** that this variable points to is held in memory obtained from
6677
** [sqlite3_malloc] and the pragma may attempt to free that memory
6678
** using [sqlite3_free].
6679
** Hence, if this variable is modified directly, either it should be
6680
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6681
** or else the use of the [temp_store_directory pragma] should be avoided.
6682
** Except when requested by the [temp_store_directory pragma], SQLite
6683
** does not free the memory that sqlite3_temp_directory points to.  If
6684
** the application wants that memory to be freed, it must do
6685
** so itself, taking care to only do so after all [database connection]
6686
** objects have been destroyed.
6687
**
6688
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
6689
** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
6690
** features that require the use of temporary files may fail.  Here is an
6691
** example of how to do this using C++ with the Windows Runtime:
6692
**
6693
** <blockquote><pre>
6694
** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
6695
** &nbsp;     TemporaryFolder->Path->Data();
6696
** char zPathBuf&#91;MAX_PATH + 1&#93;;
6697
** memset(zPathBuf, 0, sizeof(zPathBuf));
6698
** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
6699
** &nbsp;     NULL, NULL);
6700
** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
6701
** </pre></blockquote>
6702
*/
6703
SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
6704
6705
/*
6706
** CAPI3REF: Name Of The Folder Holding Database Files
6707
**
6708
** ^(If this global variable is made to point to a string which is
6709
** the name of a folder (a.k.a. directory), then all database files
6710
** specified with a relative pathname and created or accessed by
6711
** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
6712
** to be relative to that directory.)^ ^If this variable is a NULL
6713
** pointer, then SQLite assumes that all database files specified
6714
** with a relative pathname are relative to the current directory
6715
** for the process.  Only the windows VFS makes use of this global
6716
** variable; it is ignored by the unix VFS.
6717
**
6718
** Changing the value of this variable while a database connection is
6719
** open can result in a corrupt database.
6720
**
6721
** It is not safe to read or modify this variable in more than one
6722
** thread at a time.  It is not safe to read or modify this variable
6723
** if a [database connection] is being used at the same time in a separate
6724
** thread.
6725
** It is intended that this variable be set once
6726
** as part of process initialization and before any SQLite interface
6727
** routines have been called and that this variable remain unchanged
6728
** thereafter.
6729
**
6730
** ^The [data_store_directory pragma] may modify this variable and cause
6731
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
6732
** the [data_store_directory pragma] always assumes that any string
6733
** that this variable points to is held in memory obtained from
6734
** [sqlite3_malloc] and the pragma may attempt to free that memory
6735
** using [sqlite3_free].
6736
** Hence, if this variable is modified directly, either it should be
6737
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6738
** or else the use of the [data_store_directory pragma] should be avoided.
6739
*/
6740
SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
6741
6742
/*
6743
** CAPI3REF: Win32 Specific Interface
6744
**
6745
** These interfaces are available only on Windows.  The
6746
** [sqlite3_win32_set_directory] interface is used to set the value associated
6747
** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
6748
** zValue, depending on the value of the type parameter.  The zValue parameter
6749
** should be NULL to cause the previous value to be freed via [sqlite3_free];
6750
** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
6751
** prior to being used.  The [sqlite3_win32_set_directory] interface returns
6752
** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
6753
** or [SQLITE_NOMEM] if memory could not be allocated.  The value of the
6754
** [sqlite3_data_directory] variable is intended to act as a replacement for
6755
** the current directory on the sub-platforms of Win32 where that concept is
6756
** not present, e.g. WinRT and UWP.  The [sqlite3_win32_set_directory8] and
6757
** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
6758
** sqlite3_win32_set_directory interface except the string parameter must be
6759
** UTF-8 or UTF-16, respectively.
6760
*/
6761
SQLITE_API int sqlite3_win32_set_directory(
6762
  unsigned long type, /* Identifier for directory being set or reset */
6763
  void *zValue        /* New value for directory being set or reset */
6764
);
6765
SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
6766
SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
6767
6768
/*
6769
** CAPI3REF: Win32 Directory Types
6770
**
6771
** These macros are only available on Windows.  They define the allowed values
6772
** for the type argument to the [sqlite3_win32_set_directory] interface.
6773
*/
6774
#define SQLITE_WIN32_DATA_DIRECTORY_TYPE  1
6775
#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE  2
6776
6777
/*
6778
** CAPI3REF: Test For Auto-Commit Mode
6779
** KEYWORDS: {autocommit mode}
6780
** METHOD: sqlite3
6781
**
6782
** ^The sqlite3_get_autocommit() interface returns non-zero or
6783
** zero if the given database connection is or is not in autocommit mode,
6784
** respectively.  ^Autocommit mode is on by default.
6785
** ^Autocommit mode is disabled by a [BEGIN] statement.
6786
** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
6787
**
6788
** If certain kinds of errors occur on a statement within a multi-statement
6789
** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
6790
** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
6791
** transaction might be rolled back automatically.  The only way to
6792
** find out whether SQLite automatically rolled back the transaction after
6793
** an error is to use this function.
6794
**
6795
** If another thread changes the autocommit status of the database
6796
** connection while this routine is running, then the return value
6797
** is undefined.
6798
*/
6799
SQLITE_API int sqlite3_get_autocommit(sqlite3*);
6800
6801
/*
6802
** CAPI3REF: Find The Database Handle Of A Prepared Statement
6803
** METHOD: sqlite3_stmt
6804
**
6805
** ^The sqlite3_db_handle interface returns the [database connection] handle
6806
** to which a [prepared statement] belongs.  ^The [database connection]
6807
** returned by sqlite3_db_handle is the same [database connection]
6808
** that was the first argument
6809
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
6810
** create the statement in the first place.
6811
*/
6812
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
6813
6814
/*
6815
** CAPI3REF: Return The Schema Name For A Database Connection
6816
** METHOD: sqlite3
6817
**
6818
** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name
6819
** for the N-th database on database connection D, or a NULL pointer if N is
6820
** out of range.  An N value of 0 means the main database file.  An N of 1 is
6821
** the "temp" schema.  Larger values of N correspond to various ATTACH-ed
6822
** databases.
6823
**
6824
** Space to hold the string that is returned by sqlite3_db_name() is managed
6825
** by SQLite itself.  The string might be deallocated by any operation that
6826
** changes the schema, including [ATTACH] or [DETACH] or calls to
6827
** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that
6828
** occur on a different thread.  Applications that need to
6829
** remember the string long-term should make their own copy.  Applications that
6830
** are accessing the same database connection simultaneously on multiple
6831
** threads should mutex-protect calls to this API and should make their own
6832
** private copy of the result prior to releasing the mutex.
6833
*/
6834
SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N);
6835
6836
/*
6837
** CAPI3REF: Return The Filename For A Database Connection
6838
** METHOD: sqlite3
6839
**
6840
** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename
6841
** associated with database N of connection D.
6842
** ^If there is no attached database N on the database
6843
** connection D, or if database N is a temporary or in-memory database, then
6844
** this function will return either a NULL pointer or an empty string.
6845
**
6846
** ^The string value returned by this routine is owned and managed by
6847
** the database connection.  ^The value will be valid until the database N
6848
** is [DETACH]-ed or until the database connection closes.
6849
**
6850
** ^The filename returned by this function is the output of the
6851
** xFullPathname method of the [VFS].  ^In other words, the filename
6852
** will be an absolute pathname, even if the filename used
6853
** to open the database originally was a URI or relative pathname.
6854
**
6855
** If the filename pointer returned by this routine is not NULL, then it
6856
** can be used as the filename input parameter to these routines:
6857
** <ul>
6858
** <li> [sqlite3_uri_parameter()]
6859
** <li> [sqlite3_uri_boolean()]
6860
** <li> [sqlite3_uri_int64()]
6861
** <li> [sqlite3_filename_database()]
6862
** <li> [sqlite3_filename_journal()]
6863
** <li> [sqlite3_filename_wal()]
6864
** </ul>
6865
*/
6866
SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName);
6867
6868
/*
6869
** CAPI3REF: Determine if a database is read-only
6870
** METHOD: sqlite3
6871
**
6872
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
6873
** of connection D is read-only, 0 if it is read/write, or -1 if N is not
6874
** the name of a database on connection D.
6875
*/
6876
SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
6877
6878
/*
6879
** CAPI3REF: Determine the transaction state of a database
6880
** METHOD: sqlite3
6881
**
6882
** ^The sqlite3_txn_state(D,S) interface returns the current
6883
** [transaction state] of schema S in database connection D.  ^If S is NULL,
6884
** then the highest transaction state of any schema on database connection D
6885
** is returned.  Transaction states are (in order of lowest to highest):
6886
** <ol>
6887
** <li value="0"> SQLITE_TXN_NONE
6888
** <li value="1"> SQLITE_TXN_READ
6889
** <li value="2"> SQLITE_TXN_WRITE
6890
** </ol>
6891
** ^If the S argument to sqlite3_txn_state(D,S) is not the name of
6892
** a valid schema, then -1 is returned.
6893
*/
6894
SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema);
6895
6896
/*
6897
** CAPI3REF: Allowed return values from sqlite3_txn_state()
6898
** KEYWORDS: {transaction state}
6899
**
6900
** These constants define the current transaction state of a database file.
6901
** ^The [sqlite3_txn_state(D,S)] interface returns one of these
6902
** constants in order to describe the transaction state of schema S
6903
** in [database connection] D.
6904
**
6905
** <dl>
6906
** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt>
6907
** <dd>The SQLITE_TXN_NONE state means that no transaction is currently
6908
** pending.</dd>
6909
**
6910
** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt>
6911
** <dd>The SQLITE_TXN_READ state means that the database is currently
6912
** in a read transaction.  Content has been read from the database file
6913
** but nothing in the database file has changed.  The transaction state
6914
** will be advanced to SQLITE_TXN_WRITE if any changes occur and there are
6915
** no other conflicting concurrent write transactions.  The transaction
6916
** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or
6917
** [COMMIT].</dd>
6918
**
6919
** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt>
6920
** <dd>The SQLITE_TXN_WRITE state means that the database is currently
6921
** in a write transaction.  Content has been written to the database file
6922
** but has not yet committed.  The transaction state will change to
6923
** SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd>
6924
*/
6925
#define SQLITE_TXN_NONE  0
6926
#define SQLITE_TXN_READ  1
6927
#define SQLITE_TXN_WRITE 2
6928
6929
/*
6930
** CAPI3REF: Find the next prepared statement
6931
** METHOD: sqlite3
6932
**
6933
** ^This interface returns a pointer to the next [prepared statement] after
6934
** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
6935
** then this interface returns a pointer to the first prepared statement
6936
** associated with the database connection pDb.  ^If no prepared statement
6937
** satisfies the conditions of this routine, it returns NULL.
6938
**
6939
** The [database connection] pointer D in a call to
6940
** [sqlite3_next_stmt(D,S)] must refer to an open database
6941
** connection and in particular must not be a NULL pointer.
6942
*/
6943
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
6944
6945
/*
6946
** CAPI3REF: Commit And Rollback Notification Callbacks
6947
** METHOD: sqlite3
6948
**
6949
** ^The sqlite3_commit_hook() interface registers a callback
6950
** function to be invoked whenever a transaction is [COMMIT | committed].
6951
** ^Any callback set by a previous call to sqlite3_commit_hook()
6952
** for the same database connection is overridden.
6953
** ^The sqlite3_rollback_hook() interface registers a callback
6954
** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
6955
** ^Any callback set by a previous call to sqlite3_rollback_hook()
6956
** for the same database connection is overridden.
6957
** ^The pArg argument is passed through to the callback.
6958
** ^If the callback on a commit hook function returns non-zero,
6959
** then the commit is converted into a rollback.
6960
**
6961
** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
6962
** return the P argument from the previous call of the same function
6963
** on the same [database connection] D, or NULL for
6964
** the first call for each function on D.
6965
**
6966
** The commit and rollback hook callbacks are not reentrant.
6967
** The callback implementation must not do anything that will modify
6968
** the database connection that invoked the callback.  Any actions
6969
** to modify the database connection must be deferred until after the
6970
** completion of the [sqlite3_step()] call that triggered the commit
6971
** or rollback hook in the first place.
6972
** Note that running any other SQL statements, including SELECT statements,
6973
** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
6974
** the database connections for the meaning of "modify" in this paragraph.
6975
**
6976
** ^Registering a NULL function disables the callback.
6977
**
6978
** ^When the commit hook callback routine returns zero, the [COMMIT]
6979
** operation is allowed to continue normally.  ^If the commit hook
6980
** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
6981
** ^The rollback hook is invoked on a rollback that results from a commit
6982
** hook returning non-zero, just as it would be with any other rollback.
6983
**
6984
** ^For the purposes of this API, a transaction is said to have been
6985
** rolled back if an explicit "ROLLBACK" statement is executed, or
6986
** an error or constraint causes an implicit rollback to occur.
6987
** ^The rollback callback is not invoked if a transaction is
6988
** automatically rolled back because the database connection is closed.
6989
**
6990
** See also the [sqlite3_update_hook()] interface.
6991
*/
6992
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
6993
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
6994
6995
/*
6996
** CAPI3REF: Autovacuum Compaction Amount Callback
6997
** METHOD: sqlite3
6998
**
6999
** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback
7000
** function C that is invoked prior to each autovacuum of the database
7001
** file.  ^The callback is passed a copy of the generic data pointer (P),
7002
** the schema-name of the attached database that is being autovacuumed,
7003
** the size of the database file in pages, the number of free pages,
7004
** and the number of bytes per page, respectively.  The callback should
7005
** return the number of free pages that should be removed by the
7006
** autovacuum.  ^If the callback returns zero, then no autovacuum happens.
7007
** ^If the value returned is greater than or equal to the number of
7008
** free pages, then a complete autovacuum happens.
7009
**
7010
** <p>^If there are multiple ATTACH-ed database files that are being
7011
** modified as part of a transaction commit, then the autovacuum pages
7012
** callback is invoked separately for each file.
7013
**
7014
** <p><b>The callback is not reentrant.</b> The callback function should
7015
** not attempt to invoke any other SQLite interface.  If it does, bad
7016
** things may happen, including segmentation faults and corrupt database
7017
** files.  The callback function should be a simple function that
7018
** does some arithmetic on its input parameters and returns a result.
7019
**
7020
** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional
7021
** destructor for the P parameter.  ^If X is not NULL, then X(P) is
7022
** invoked whenever the database connection closes or when the callback
7023
** is overwritten by another invocation of sqlite3_autovacuum_pages().
7024
**
7025
** <p>^There is only one autovacuum pages callback per database connection.
7026
** ^Each call to the sqlite3_autovacuum_pages() interface overrides all
7027
** previous invocations for that database connection.  ^If the callback
7028
** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer,
7029
** then the autovacuum steps callback is canceled.  The return value
7030
** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might
7031
** be some other error code if something goes wrong.  The current
7032
** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other
7033
** return codes might be added in future releases.
7034
**
7035
** <p>If no autovacuum pages callback is specified (the usual case) or
7036
** a NULL pointer is provided for the callback,
7037
** then the default behavior is to vacuum all free pages.  So, in other
7038
** words, the default behavior is the same as if the callback function
7039
** were something like this:
7040
**
7041
** <blockquote><pre>
7042
** &nbsp;   unsigned int demonstration_autovac_pages_callback(
7043
** &nbsp;     void *pClientData,
7044
** &nbsp;     const char *zSchema,
7045
** &nbsp;     unsigned int nDbPage,
7046
** &nbsp;     unsigned int nFreePage,
7047
** &nbsp;     unsigned int nBytePerPage
7048
** &nbsp;   ){
7049
** &nbsp;     return nFreePage;
7050
** &nbsp;   }
7051
** </pre></blockquote>
7052
*/
7053
SQLITE_API int sqlite3_autovacuum_pages(
7054
  sqlite3 *db,
7055
  unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int),
7056
  void*,
7057
  void(*)(void*)
7058
);
7059
7060
7061
/*
7062
** CAPI3REF: Data Change Notification Callbacks
7063
** METHOD: sqlite3
7064
**
7065
** ^The sqlite3_update_hook() interface registers a callback function
7066
** with the [database connection] identified by the first argument
7067
** to be invoked whenever a row is updated, inserted or deleted in
7068
** a [rowid table].
7069
** ^Any callback set by a previous call to this function
7070
** for the same database connection is overridden.
7071
**
7072
** ^The second argument is a pointer to the function to invoke when a
7073
** row is updated, inserted or deleted in a rowid table.
7074
** ^The update hook is disabled by invoking sqlite3_update_hook()
7075
** with a NULL pointer as the second parameter.
7076
** ^The first argument to the callback is a copy of the third argument
7077
** to sqlite3_update_hook().
7078
** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
7079
** or [SQLITE_UPDATE], depending on the operation that caused the callback
7080
** to be invoked.
7081
** ^The third and fourth arguments to the callback contain pointers to the
7082
** database and table name containing the affected row.
7083
** ^The final callback parameter is the [rowid] of the row.
7084
** ^In the case of an update, this is the [rowid] after the update takes place.
7085
**
7086
** ^(The update hook is not invoked when internal system tables are
7087
** modified (i.e. sqlite_sequence).)^
7088
** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
7089
**
7090
** ^In the current implementation, the update hook
7091
** is not invoked when conflicting rows are deleted because of an
7092
** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
7093
** invoked when rows are deleted using the [truncate optimization].
7094
** The exceptions defined in this paragraph might change in a future
7095
** release of SQLite.
7096
**
7097
** Whether the update hook is invoked before or after the
7098
** corresponding change is currently unspecified and may differ
7099
** depending on the type of change. Do not rely on the order of the
7100
** hook call with regards to the final result of the operation which
7101
** triggers the hook.
7102
**
7103
** The update hook implementation must not do anything that will modify
7104
** the database connection that invoked the update hook.  Any actions
7105
** to modify the database connection must be deferred until after the
7106
** completion of the [sqlite3_step()] call that triggered the update hook.
7107
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
7108
** database connections for the meaning of "modify" in this paragraph.
7109
**
7110
** ^The sqlite3_update_hook(D,C,P) function
7111
** returns the P argument from the previous call
7112
** on the same [database connection] D, or NULL for
7113
** the first call on D.
7114
**
7115
** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
7116
** and [sqlite3_preupdate_hook()] interfaces.
7117
*/
7118
SQLITE_API void *sqlite3_update_hook(
7119
  sqlite3*,
7120
  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
7121
  void*
7122
);
7123
7124
/*
7125
** CAPI3REF: Enable Or Disable Shared Pager Cache
7126
**
7127
** ^(This routine enables or disables the sharing of the database cache
7128
** and schema data structures between [database connection | connections]
7129
** to the same database. Sharing is enabled if the argument is true
7130
** and disabled if the argument is false.)^
7131
**
7132
** This interface is omitted if SQLite is compiled with
7133
** [-DSQLITE_OMIT_SHARED_CACHE].  The [-DSQLITE_OMIT_SHARED_CACHE]
7134
** compile-time option is recommended because the
7135
** [use of shared cache mode is discouraged].
7136
**
7137
** ^Cache sharing is enabled and disabled for an entire process.
7138
** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
7139
** In prior versions of SQLite,
7140
** sharing was enabled or disabled for each thread separately.
7141
**
7142
** ^(The cache sharing mode set by this interface effects all subsequent
7143
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
7144
** Existing database connections continue to use the sharing mode
7145
** that was in effect at the time they were opened.)^
7146
**
7147
** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
7148
** successfully.  An [error code] is returned otherwise.)^
7149
**
7150
** ^Shared cache is disabled by default. It is recommended that it stay
7151
** that way.  In other words, do not use this routine.  This interface
7152
** continues to be provided for historical compatibility, but its use is
7153
** discouraged.  Any use of shared cache is discouraged.  If shared cache
7154
** must be used, it is recommended that shared cache only be enabled for
7155
** individual database connections using the [sqlite3_open_v2()] interface
7156
** with the [SQLITE_OPEN_SHAREDCACHE] flag.
7157
**
7158
** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
7159
** and will always return SQLITE_MISUSE. On those systems,
7160
** shared cache mode should be enabled per-database connection via
7161
** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
7162
**
7163
** This interface is threadsafe on processors where writing a
7164
** 32-bit integer is atomic.
7165
**
7166
** See Also:  [SQLite Shared-Cache Mode]
7167
*/
7168
SQLITE_API int sqlite3_enable_shared_cache(int);
7169
7170
/*
7171
** CAPI3REF: Attempt To Free Heap Memory
7172
**
7173
** ^The sqlite3_release_memory() interface attempts to free N bytes
7174
** of heap memory by deallocating non-essential memory allocations
7175
** held by the database library.   Memory used to cache database
7176
** pages to improve performance is an example of non-essential memory.
7177
** ^sqlite3_release_memory() returns the number of bytes actually freed,
7178
** which might be more or less than the amount requested.
7179
** ^The sqlite3_release_memory() routine is a no-op returning zero
7180
** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
7181
**
7182
** See also: [sqlite3_db_release_memory()]
7183
*/
7184
SQLITE_API int sqlite3_release_memory(int);
7185
7186
/*
7187
** CAPI3REF: Free Memory Used By A Database Connection
7188
** METHOD: sqlite3
7189
**
7190
** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
7191
** memory as possible from database connection D. Unlike the
7192
** [sqlite3_release_memory()] interface, this interface is in effect even
7193
** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
7194
** omitted.
7195
**
7196
** See also: [sqlite3_release_memory()]
7197
*/
7198
SQLITE_API int sqlite3_db_release_memory(sqlite3*);
7199
7200
/*
7201
** CAPI3REF: Impose A Limit On Heap Size
7202
**
7203
** These interfaces impose limits on the amount of heap memory that will be
7204
** used by all database connections within a single process.
7205
**
7206
** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
7207
** soft limit on the amount of heap memory that may be allocated by SQLite.
7208
** ^SQLite strives to keep heap memory utilization below the soft heap
7209
** limit by reducing the number of pages held in the page cache
7210
** as heap memory usages approaches the limit.
7211
** ^The soft heap limit is "soft" because even though SQLite strives to stay
7212
** below the limit, it will exceed the limit rather than generate
7213
** an [SQLITE_NOMEM] error.  In other words, the soft heap limit
7214
** is advisory only.
7215
**
7216
** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of
7217
** N bytes on the amount of memory that will be allocated.  ^The
7218
** sqlite3_hard_heap_limit64(N) interface is similar to
7219
** sqlite3_soft_heap_limit64(N) except that memory allocations will fail
7220
** when the hard heap limit is reached.
7221
**
7222
** ^The return value from both sqlite3_soft_heap_limit64() and
7223
** sqlite3_hard_heap_limit64() is the size of
7224
** the heap limit prior to the call, or negative in the case of an
7225
** error.  ^If the argument N is negative
7226
** then no change is made to the heap limit.  Hence, the current
7227
** size of heap limits can be determined by invoking
7228
** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
7229
**
7230
** ^Setting the heap limits to zero disables the heap limiter mechanism.
7231
**
7232
** ^The soft heap limit may not be greater than the hard heap limit.
7233
** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
7234
** is invoked with a value of N that is greater than the hard heap limit,
7235
** the soft heap limit is set to the value of the hard heap limit.
7236
** ^The soft heap limit is automatically enabled whenever the hard heap
7237
** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
7238
** the soft heap limit is outside the range of 1..N, then the soft heap
7239
** limit is set to N.  ^Invoking sqlite3_soft_heap_limit64(0) when the
7240
** hard heap limit is enabled makes the soft heap limit equal to the
7241
** hard heap limit.
7242
**
7243
** The memory allocation limits can also be adjusted using
7244
** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit].
7245
**
7246
** ^(The heap limits are not enforced in the current implementation
7247
** if one or more of following conditions are true:
7248
**
7249
** <ul>
7250
** <li> The limit value is set to zero.
7251
** <li> Memory accounting is disabled using a combination of the
7252
**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
7253
**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
7254
** <li> An alternative page cache implementation is specified using
7255
**      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
7256
** <li> The page cache allocates from its own memory pool supplied
7257
**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
7258
**      from the heap.
7259
** </ul>)^
7260
**
7261
** The circumstances under which SQLite will enforce the heap limits may
7262
** change in future releases of SQLite.
7263
*/
7264
SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
7265
SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N);
7266
7267
/*
7268
** CAPI3REF: Deprecated Soft Heap Limit Interface
7269
** DEPRECATED
7270
**
7271
** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
7272
** interface.  This routine is provided for historical compatibility
7273
** only.  All new applications should use the
7274
** [sqlite3_soft_heap_limit64()] interface rather than this one.
7275
*/
7276
SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
7277
7278
7279
/*
7280
** CAPI3REF: Extract Metadata About A Column Of A Table
7281
** METHOD: sqlite3
7282
**
7283
** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
7284
** information about column C of table T in database D
7285
** on [database connection] X.)^  ^The sqlite3_table_column_metadata()
7286
** interface returns SQLITE_OK and fills in the non-NULL pointers in
7287
** the final five arguments with appropriate values if the specified
7288
** column exists.  ^The sqlite3_table_column_metadata() interface returns
7289
** SQLITE_ERROR if the specified column does not exist.
7290
** ^If the column-name parameter to sqlite3_table_column_metadata() is a
7291
** NULL pointer, then this routine simply checks for the existence of the
7292
** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
7293
** does not.  If the table name parameter T in a call to
7294
** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
7295
** undefined behavior.
7296
**
7297
** ^The column is identified by the second, third and fourth parameters to
7298
** this function. ^(The second parameter is either the name of the database
7299
** (i.e. "main", "temp", or an attached database) containing the specified
7300
** table or NULL.)^ ^If it is NULL, then all attached databases are searched
7301
** for the table using the same algorithm used by the database engine to
7302
** resolve unqualified table references.
7303
**
7304
** ^The third and fourth parameters to this function are the table and column
7305
** name of the desired column, respectively.
7306
**
7307
** ^Metadata is returned by writing to the memory locations passed as the 5th
7308
** and subsequent parameters to this function. ^Any of these arguments may be
7309
** NULL, in which case the corresponding element of metadata is omitted.
7310
**
7311
** ^(<blockquote>
7312
** <table border="1">
7313
** <tr><th> Parameter <th> Output<br>Type <th>  Description
7314
**
7315
** <tr><td> 5th <td> const char* <td> Data type
7316
** <tr><td> 6th <td> const char* <td> Name of default collation sequence
7317
** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
7318
** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
7319
** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
7320
** </table>
7321
** </blockquote>)^
7322
**
7323
** ^The memory pointed to by the character pointers returned for the
7324
** declaration type and collation sequence is valid until the next
7325
** call to any SQLite API function.
7326
**
7327
** ^If the specified table is actually a view, an [error code] is returned.
7328
**
7329
** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
7330
** is not a [WITHOUT ROWID] table and an
7331
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
7332
** parameters are set for the explicitly declared column. ^(If there is no
7333
** [INTEGER PRIMARY KEY] column, then the outputs
7334
** for the [rowid] are set as follows:
7335
**
7336
** <pre>
7337
**     data type: "INTEGER"
7338
**     collation sequence: "BINARY"
7339
**     not null: 0
7340
**     primary key: 1
7341
**     auto increment: 0
7342
** </pre>)^
7343
**
7344
** ^This function causes all database schemas to be read from disk and
7345
** parsed, if that has not already been done, and returns an error if
7346
** any errors are encountered while loading the schema.
7347
*/
7348
SQLITE_API int sqlite3_table_column_metadata(
7349
  sqlite3 *db,                /* Connection handle */
7350
  const char *zDbName,        /* Database name or NULL */
7351
  const char *zTableName,     /* Table name */
7352
  const char *zColumnName,    /* Column name */
7353
  char const **pzDataType,    /* OUTPUT: Declared data type */
7354
  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
7355
  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
7356
  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
7357
  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
7358
);
7359
7360
/*
7361
** CAPI3REF: Load An Extension
7362
** METHOD: sqlite3
7363
**
7364
** ^This interface loads an SQLite extension library from the named file.
7365
**
7366
** ^The sqlite3_load_extension() interface attempts to load an
7367
** [SQLite extension] library contained in the file zFile.  If
7368
** the file cannot be loaded directly, attempts are made to load
7369
** with various operating-system specific extensions added.
7370
** So for example, if "samplelib" cannot be loaded, then names like
7371
** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
7372
** be tried also.
7373
**
7374
** ^The entry point is zProc.
7375
** ^(zProc may be 0, in which case SQLite will try to come up with an
7376
** entry point name on its own.  It first tries "sqlite3_extension_init".
7377
** If that does not work, it constructs a name "sqlite3_X_init" where
7378
** X consists of the lower-case equivalent of all ASCII alphabetic
7379
** characters in the filename from the last "/" to the first following
7380
** "." and omitting any initial "lib".)^
7381
** ^The sqlite3_load_extension() interface returns
7382
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
7383
** ^If an error occurs and pzErrMsg is not 0, then the
7384
** [sqlite3_load_extension()] interface shall attempt to
7385
** fill *pzErrMsg with error message text stored in memory
7386
** obtained from [sqlite3_malloc()]. The calling function
7387
** should free this memory by calling [sqlite3_free()].
7388
**
7389
** ^Extension loading must be enabled using
7390
** [sqlite3_enable_load_extension()] or
7391
** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
7392
** prior to calling this API,
7393
** otherwise an error will be returned.
7394
**
7395
** <b>Security warning:</b> It is recommended that the
7396
** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
7397
** interface.  The use of the [sqlite3_enable_load_extension()] interface
7398
** should be avoided.  This will keep the SQL function [load_extension()]
7399
** disabled and prevent SQL injections from giving attackers
7400
** access to extension loading capabilities.
7401
**
7402
** See also the [load_extension() SQL function].
7403
*/
7404
SQLITE_API int sqlite3_load_extension(
7405
  sqlite3 *db,          /* Load the extension into this database connection */
7406
  const char *zFile,    /* Name of the shared library containing extension */
7407
  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
7408
  char **pzErrMsg       /* Put error message here if not 0 */
7409
);
7410
7411
/*
7412
** CAPI3REF: Enable Or Disable Extension Loading
7413
** METHOD: sqlite3
7414
**
7415
** ^So as not to open security holes in older applications that are
7416
** unprepared to deal with [extension loading], and as a means of disabling
7417
** [extension loading] while evaluating user-entered SQL, the following API
7418
** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
7419
**
7420
** ^Extension loading is off by default.
7421
** ^Call the sqlite3_enable_load_extension() routine with onoff==1
7422
** to turn extension loading on and call it with onoff==0 to turn
7423
** it back off again.
7424
**
7425
** ^This interface enables or disables both the C-API
7426
** [sqlite3_load_extension()] and the SQL function [load_extension()].
7427
** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
7428
** to enable or disable only the C-API.)^
7429
**
7430
** <b>Security warning:</b> It is recommended that extension loading
7431
** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
7432
** rather than this interface, so the [load_extension()] SQL function
7433
** remains disabled. This will prevent SQL injections from giving attackers
7434
** access to extension loading capabilities.
7435
*/
7436
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
7437
7438
/*
7439
** CAPI3REF: Automatically Load Statically Linked Extensions
7440
**
7441
** ^This interface causes the xEntryPoint() function to be invoked for
7442
** each new [database connection] that is created.  The idea here is that
7443
** xEntryPoint() is the entry point for a statically linked [SQLite extension]
7444
** that is to be automatically loaded into all new database connections.
7445
**
7446
** ^(Even though the function prototype shows that xEntryPoint() takes
7447
** no arguments and returns void, SQLite invokes xEntryPoint() with three
7448
** arguments and expects an integer result as if the signature of the
7449
** entry point were as follows:
7450
**
7451
** <blockquote><pre>
7452
** &nbsp;  int xEntryPoint(
7453
** &nbsp;    sqlite3 *db,
7454
** &nbsp;    const char **pzErrMsg,
7455
** &nbsp;    const struct sqlite3_api_routines *pThunk
7456
** &nbsp;  );
7457
** </pre></blockquote>)^
7458
**
7459
** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
7460
** point to an appropriate error message (obtained from [sqlite3_mprintf()])
7461
** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
7462
** is NULL before calling the xEntryPoint().  ^SQLite will invoke
7463
** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
7464
** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
7465
** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
7466
**
7467
** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
7468
** on the list of automatic extensions is a harmless no-op. ^No entry point
7469
** will be called more than once for each database connection that is opened.
7470
**
7471
** See also: [sqlite3_reset_auto_extension()]
7472
** and [sqlite3_cancel_auto_extension()]
7473
*/
7474
SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
7475
7476
/*
7477
** CAPI3REF: Cancel Automatic Extension Loading
7478
**
7479
** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
7480
** initialization routine X that was registered using a prior call to
7481
** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
7482
** routine returns 1 if initialization routine X was successfully
7483
** unregistered and it returns 0 if X was not on the list of initialization
7484
** routines.
7485
*/
7486
SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
7487
7488
/*
7489
** CAPI3REF: Reset Automatic Extension Loading
7490
**
7491
** ^This interface disables all automatic extensions previously
7492
** registered using [sqlite3_auto_extension()].
7493
*/
7494
SQLITE_API void sqlite3_reset_auto_extension(void);
7495
7496
/*
7497
** Structures used by the virtual table interface
7498
*/
7499
typedef struct sqlite3_vtab sqlite3_vtab;
7500
typedef struct sqlite3_index_info sqlite3_index_info;
7501
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
7502
typedef struct sqlite3_module sqlite3_module;
7503
7504
/*
7505
** CAPI3REF: Virtual Table Object
7506
** KEYWORDS: sqlite3_module {virtual table module}
7507
**
7508
** This structure, sometimes called a "virtual table module",
7509
** defines the implementation of a [virtual table].
7510
** This structure consists mostly of methods for the module.
7511
**
7512
** ^A virtual table module is created by filling in a persistent
7513
** instance of this structure and passing a pointer to that instance
7514
** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
7515
** ^The registration remains valid until it is replaced by a different
7516
** module or until the [database connection] closes.  The content
7517
** of this structure must not change while it is registered with
7518
** any database connection.
7519
*/
7520
struct sqlite3_module {
7521
  int iVersion;
7522
  int (*xCreate)(sqlite3*, void *pAux,
7523
               int argc, const char *const*argv,
7524
               sqlite3_vtab **ppVTab, char**);
7525
  int (*xConnect)(sqlite3*, void *pAux,
7526
               int argc, const char *const*argv,
7527
               sqlite3_vtab **ppVTab, char**);
7528
  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
7529
  int (*xDisconnect)(sqlite3_vtab *pVTab);
7530
  int (*xDestroy)(sqlite3_vtab *pVTab);
7531
  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
7532
  int (*xClose)(sqlite3_vtab_cursor*);
7533
  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
7534
                int argc, sqlite3_value **argv);
7535
  int (*xNext)(sqlite3_vtab_cursor*);
7536
  int (*xEof)(sqlite3_vtab_cursor*);
7537
  int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
7538
  int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
7539
  int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
7540
  int (*xBegin)(sqlite3_vtab *pVTab);
7541
  int (*xSync)(sqlite3_vtab *pVTab);
7542
  int (*xCommit)(sqlite3_vtab *pVTab);
7543
  int (*xRollback)(sqlite3_vtab *pVTab);
7544
  int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
7545
                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
7546
                       void **ppArg);
7547
  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
7548
  /* The methods above are in version 1 of the sqlite_module object. Those
7549
  ** below are for version 2 and greater. */
7550
  int (*xSavepoint)(sqlite3_vtab *pVTab, int);
7551
  int (*xRelease)(sqlite3_vtab *pVTab, int);
7552
  int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
7553
  /* The methods above are in versions 1 and 2 of the sqlite_module object.
7554
  ** Those below are for version 3 and greater. */
7555
  int (*xShadowName)(const char*);
7556
  /* The methods above are in versions 1 through 3 of the sqlite_module object.
7557
  ** Those below are for version 4 and greater. */
7558
  int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema,
7559
                    const char *zTabName, int mFlags, char **pzErr);
7560
};
7561
7562
/*
7563
** CAPI3REF: Virtual Table Indexing Information
7564
** KEYWORDS: sqlite3_index_info
7565
**
7566
** The sqlite3_index_info structure and its substructures is used as part
7567
** of the [virtual table] interface to
7568
** pass information into and receive the reply from the [xBestIndex]
7569
** method of a [virtual table module].  The fields under **Inputs** are the
7570
** inputs to xBestIndex and are read-only.  xBestIndex inserts its
7571
** results into the **Outputs** fields.
7572
**
7573
** ^(The aConstraint[] array records WHERE clause constraints of the form:
7574
**
7575
** <blockquote>column OP expr</blockquote>
7576
**
7577
** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
7578
** stored in aConstraint[].op using one of the
7579
** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
7580
** ^(The index of the column is stored in
7581
** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
7582
** expr on the right-hand side can be evaluated (and thus the constraint
7583
** is usable) and false if it cannot.)^
7584
**
7585
** ^The optimizer automatically inverts terms of the form "expr OP column"
7586
** and makes other simplifications to the WHERE clause in an attempt to
7587
** get as many WHERE clause terms into the form shown above as possible.
7588
** ^The aConstraint[] array only reports WHERE clause terms that are
7589
** relevant to the particular virtual table being queried.
7590
**
7591
** ^Information about the ORDER BY clause is stored in aOrderBy[].
7592
** ^Each term of aOrderBy records a column of the ORDER BY clause.
7593
**
7594
** The colUsed field indicates which columns of the virtual table may be
7595
** required by the current scan. Virtual table columns are numbered from
7596
** zero in the order in which they appear within the CREATE TABLE statement
7597
** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
7598
** the corresponding bit is set within the colUsed mask if the column may be
7599
** required by SQLite. If the table has at least 64 columns and any column
7600
** to the right of the first 63 is required, then bit 63 of colUsed is also
7601
** set. In other words, column iCol may be required if the expression
7602
** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
7603
** non-zero.
7604
**
7605
** The [xBestIndex] method must fill aConstraintUsage[] with information
7606
** about what parameters to pass to xFilter.  ^If argvIndex>0 then
7607
** the right-hand side of the corresponding aConstraint[] is evaluated
7608
** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
7609
** is true, then the constraint is assumed to be fully handled by the
7610
** virtual table and might not be checked again by the byte code.)^ ^(The
7611
** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
7612
** is left in its default setting of false, the constraint will always be
7613
** checked separately in byte code.  If the omit flag is changed to true, then
7614
** the constraint may or may not be checked in byte code.  In other words,
7615
** when the omit flag is true there is no guarantee that the constraint will
7616
** not be checked again using byte code.)^
7617
**
7618
** ^The idxNum and idxStr values are recorded and passed into the
7619
** [xFilter] method.
7620
** ^[sqlite3_free()] is used to free idxStr if and only if
7621
** needToFreeIdxStr is true.
7622
**
7623
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
7624
** the correct order to satisfy the ORDER BY clause so that no separate
7625
** sorting step is required.
7626
**
7627
** ^The estimatedCost value is an estimate of the cost of a particular
7628
** strategy. A cost of N indicates that the cost of the strategy is similar
7629
** to a linear scan of an SQLite table with N rows. A cost of log(N)
7630
** indicates that the expense of the operation is similar to that of a
7631
** binary search on a unique indexed field of an SQLite table with N rows.
7632
**
7633
** ^The estimatedRows value is an estimate of the number of rows that
7634
** will be returned by the strategy.
7635
**
7636
** The xBestIndex method may optionally populate the idxFlags field with a
7637
** mask of SQLITE_INDEX_SCAN_* flags. One such flag is
7638
** [SQLITE_INDEX_SCAN_HEX], which if set causes the [EXPLAIN QUERY PLAN]
7639
** output to show the idxNum as hex instead of as decimal.  Another flag is
7640
** SQLITE_INDEX_SCAN_UNIQUE, which if set indicates that the query plan will
7641
** return at most one row.
7642
**
7643
** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
7644
** SQLite also assumes that if a call to the xUpdate() method is made as
7645
** part of the same statement to delete or update a virtual table row and the
7646
** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
7647
** any database changes. In other words, if the xUpdate() returns
7648
** SQLITE_CONSTRAINT, the database contents must be exactly as they were
7649
** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
7650
** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
7651
** the xUpdate method are automatically rolled back by SQLite.
7652
**
7653
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
7654
** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
7655
** If a virtual table extension is
7656
** used with an SQLite version earlier than 3.8.2, the results of attempting
7657
** to read or write the estimatedRows field are undefined (but are likely
7658
** to include crashing the application). The estimatedRows field should
7659
** therefore only be used if [sqlite3_libversion_number()] returns a
7660
** value greater than or equal to 3008002. Similarly, the idxFlags field
7661
** was added for [version 3.9.0] ([dateof:3.9.0]).
7662
** It may therefore only be used if
7663
** sqlite3_libversion_number() returns a value greater than or equal to
7664
** 3009000.
7665
*/
7666
struct sqlite3_index_info {
7667
  /* Inputs */
7668
  int nConstraint;           /* Number of entries in aConstraint */
7669
  struct sqlite3_index_constraint {
7670
     int iColumn;              /* Column constrained.  -1 for ROWID */
7671
     unsigned char op;         /* Constraint operator */
7672
     unsigned char usable;     /* True if this constraint is usable */
7673
     int iTermOffset;          /* Used internally - xBestIndex should ignore */
7674
  } *aConstraint;            /* Table of WHERE clause constraints */
7675
  int nOrderBy;              /* Number of terms in the ORDER BY clause */
7676
  struct sqlite3_index_orderby {
7677
     int iColumn;              /* Column number */
7678
     unsigned char desc;       /* True for DESC.  False for ASC. */
7679
  } *aOrderBy;               /* The ORDER BY clause */
7680
  /* Outputs */
7681
  struct sqlite3_index_constraint_usage {
7682
    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
7683
    unsigned char omit;      /* Do not code a test for this constraint */
7684
  } *aConstraintUsage;
7685
  int idxNum;                /* Number used to identify the index */
7686
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
7687
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
7688
  int orderByConsumed;       /* True if output is already ordered */
7689
  double estimatedCost;           /* Estimated cost of using this index */
7690
  /* Fields below are only available in SQLite 3.8.2 and later */
7691
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
7692
  /* Fields below are only available in SQLite 3.9.0 and later */
7693
  int idxFlags;              /* Mask of SQLITE_INDEX_SCAN_* flags */
7694
  /* Fields below are only available in SQLite 3.10.0 and later */
7695
  sqlite3_uint64 colUsed;    /* Input: Mask of columns used by statement */
7696
};
7697
7698
/*
7699
** CAPI3REF: Virtual Table Scan Flags
7700
**
7701
** Virtual table implementations are allowed to set the
7702
** [sqlite3_index_info].idxFlags field to some combination of
7703
** these bits.
7704
*/
7705
#define SQLITE_INDEX_SCAN_UNIQUE 0x00000001 /* Scan visits at most 1 row */
7706
#define SQLITE_INDEX_SCAN_HEX    0x00000002 /* Display idxNum as hex */
7707
                                            /* in EXPLAIN QUERY PLAN */
7708
7709
/*
7710
** CAPI3REF: Virtual Table Constraint Operator Codes
7711
**
7712
** These macros define the allowed values for the
7713
** [sqlite3_index_info].aConstraint[].op field.  Each value represents
7714
** an operator that is part of a constraint term in the WHERE clause of
7715
** a query that uses a [virtual table].
7716
**
7717
** ^The left-hand operand of the operator is given by the corresponding
7718
** aConstraint[].iColumn field.  ^An iColumn of -1 indicates the left-hand
7719
** operand is the rowid.
7720
** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET
7721
** operators have no left-hand operand, and so for those operators the
7722
** corresponding aConstraint[].iColumn is meaningless and should not be
7723
** used.
7724
**
7725
** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through
7726
** value 255 are reserved to represent functions that are overloaded
7727
** by the [xFindFunction|xFindFunction method] of the virtual table
7728
** implementation.
7729
**
7730
** The right-hand operands for each constraint might be accessible using
7731
** the [sqlite3_vtab_rhs_value()] interface.  Usually the right-hand
7732
** operand is only available if it appears as a single constant literal
7733
** in the input SQL.  If the right-hand operand is another column or an
7734
** expression (even a constant expression) or a parameter, then the
7735
** sqlite3_vtab_rhs_value() probably will not be able to extract it.
7736
** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and
7737
** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand
7738
** and hence calls to sqlite3_vtab_rhs_value() for those operators will
7739
** always return SQLITE_NOTFOUND.
7740
**
7741
** The collating sequence to be used for comparison can be found using
7742
** the [sqlite3_vtab_collation()] interface.  For most real-world virtual
7743
** tables, the collating sequence of constraints does not matter (for example
7744
** because the constraints are numeric) and so the sqlite3_vtab_collation()
7745
** interface is not commonly needed.
7746
*/
7747
#define SQLITE_INDEX_CONSTRAINT_EQ          2
7748
#define SQLITE_INDEX_CONSTRAINT_GT          4
7749
#define SQLITE_INDEX_CONSTRAINT_LE          8
7750
#define SQLITE_INDEX_CONSTRAINT_LT         16
7751
#define SQLITE_INDEX_CONSTRAINT_GE         32
7752
#define SQLITE_INDEX_CONSTRAINT_MATCH      64
7753
#define SQLITE_INDEX_CONSTRAINT_LIKE       65
7754
#define SQLITE_INDEX_CONSTRAINT_GLOB       66
7755
#define SQLITE_INDEX_CONSTRAINT_REGEXP     67
7756
#define SQLITE_INDEX_CONSTRAINT_NE         68
7757
#define SQLITE_INDEX_CONSTRAINT_ISNOT      69
7758
#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL  70
7759
#define SQLITE_INDEX_CONSTRAINT_ISNULL     71
7760
#define SQLITE_INDEX_CONSTRAINT_IS         72
7761
#define SQLITE_INDEX_CONSTRAINT_LIMIT      73
7762
#define SQLITE_INDEX_CONSTRAINT_OFFSET     74
7763
#define SQLITE_INDEX_CONSTRAINT_FUNCTION  150
7764
7765
/*
7766
** CAPI3REF: Register A Virtual Table Implementation
7767
** METHOD: sqlite3
7768
**
7769
** ^These routines are used to register a new [virtual table module] name.
7770
** ^Module names must be registered before
7771
** creating a new [virtual table] using the module and before using a
7772
** preexisting [virtual table] for the module.
7773
**
7774
** ^The module name is registered on the [database connection] specified
7775
** by the first parameter.  ^The name of the module is given by the
7776
** second parameter.  ^The third parameter is a pointer to
7777
** the implementation of the [virtual table module].   ^The fourth
7778
** parameter is an arbitrary client data pointer that is passed through
7779
** into the [xCreate] and [xConnect] methods of the virtual table module
7780
** when a new virtual table is being created or reinitialized.
7781
**
7782
** ^The sqlite3_create_module_v2() interface has a fifth parameter which
7783
** is a pointer to a destructor for the pClientData.  ^SQLite will
7784
** invoke the destructor function (if it is not NULL) when SQLite
7785
** no longer needs the pClientData pointer.  ^The destructor will also
7786
** be invoked if the call to sqlite3_create_module_v2() fails.
7787
** ^The sqlite3_create_module()
7788
** interface is equivalent to sqlite3_create_module_v2() with a NULL
7789
** destructor.
7790
**
7791
** ^If the third parameter (the pointer to the sqlite3_module object) is
7792
** NULL then no new module is created and any existing modules with the
7793
** same name are dropped.
7794
**
7795
** See also: [sqlite3_drop_modules()]
7796
*/
7797
SQLITE_API int sqlite3_create_module(
7798
  sqlite3 *db,               /* SQLite connection to register module with */
7799
  const char *zName,         /* Name of the module */
7800
  const sqlite3_module *p,   /* Methods for the module */
7801
  void *pClientData          /* Client data for xCreate/xConnect */
7802
);
7803
SQLITE_API int sqlite3_create_module_v2(
7804
  sqlite3 *db,               /* SQLite connection to register module with */
7805
  const char *zName,         /* Name of the module */
7806
  const sqlite3_module *p,   /* Methods for the module */
7807
  void *pClientData,         /* Client data for xCreate/xConnect */
7808
  void(*xDestroy)(void*)     /* Module destructor function */
7809
);
7810
7811
/*
7812
** CAPI3REF: Remove Unnecessary Virtual Table Implementations
7813
** METHOD: sqlite3
7814
**
7815
** ^The sqlite3_drop_modules(D,L) interface removes all virtual
7816
** table modules from database connection D except those named on list L.
7817
** The L parameter must be either NULL or a pointer to an array of pointers
7818
** to strings where the array is terminated by a single NULL pointer.
7819
** ^If the L parameter is NULL, then all virtual table modules are removed.
7820
**
7821
** See also: [sqlite3_create_module()]
7822
*/
7823
SQLITE_API int sqlite3_drop_modules(
7824
  sqlite3 *db,                /* Remove modules from this connection */
7825
  const char **azKeep         /* Except, do not remove the ones named here */
7826
);
7827
7828
/*
7829
** CAPI3REF: Virtual Table Instance Object
7830
** KEYWORDS: sqlite3_vtab
7831
**
7832
** Every [virtual table module] implementation uses a subclass
7833
** of this object to describe a particular instance
7834
** of the [virtual table].  Each subclass will
7835
** be tailored to the specific needs of the module implementation.
7836
** The purpose of this superclass is to define certain fields that are
7837
** common to all module implementations.
7838
**
7839
** ^Virtual tables methods can set an error message by assigning a
7840
** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
7841
** take care that any prior string is freed by a call to [sqlite3_free()]
7842
** prior to assigning a new string to zErrMsg.  ^After the error message
7843
** is delivered up to the client application, the string will be automatically
7844
** freed by sqlite3_free() and the zErrMsg field will be zeroed.
7845
*/
7846
struct sqlite3_vtab {
7847
  const sqlite3_module *pModule;  /* The module for this virtual table */
7848
  int nRef;                       /* Number of open cursors */
7849
  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
7850
  /* Virtual table implementations will typically add additional fields */
7851
};
7852
7853
/*
7854
** CAPI3REF: Virtual Table Cursor Object
7855
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
7856
**
7857
** Every [virtual table module] implementation uses a subclass of the
7858
** following structure to describe cursors that point into the
7859
** [virtual table] and are used
7860
** to loop through the virtual table.  Cursors are created using the
7861
** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
7862
** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
7863
** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
7864
** of the module.  Each module implementation will define
7865
** the content of a cursor structure to suit its own needs.
7866
**
7867
** This superclass exists in order to define fields of the cursor that
7868
** are common to all implementations.
7869
*/
7870
struct sqlite3_vtab_cursor {
7871
  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
7872
  /* Virtual table implementations will typically add additional fields */
7873
};
7874
7875
/*
7876
** CAPI3REF: Declare The Schema Of A Virtual Table
7877
**
7878
** ^The [xCreate] and [xConnect] methods of a
7879
** [virtual table module] call this interface
7880
** to declare the format (the names and datatypes of the columns) of
7881
** the virtual tables they implement.
7882
*/
7883
SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
7884
7885
/*
7886
** CAPI3REF: Overload A Function For A Virtual Table
7887
** METHOD: sqlite3
7888
**
7889
** ^(Virtual tables can provide alternative implementations of functions
7890
** using the [xFindFunction] method of the [virtual table module].
7891
** But global versions of those functions
7892
** must exist in order to be overloaded.)^
7893
**
7894
** ^(This API makes sure a global version of a function with a particular
7895
** name and number of parameters exists.  If no such function exists
7896
** before this API is called, a new function is created.)^  ^The implementation
7897
** of the new function always causes an exception to be thrown.  So
7898
** the new function is not good for anything by itself.  Its only
7899
** purpose is to be a placeholder function that can be overloaded
7900
** by a [virtual table].
7901
*/
7902
SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
7903
7904
/*
7905
** CAPI3REF: A Handle To An Open BLOB
7906
** KEYWORDS: {BLOB handle} {BLOB handles}
7907
**
7908
** An instance of this object represents an open BLOB on which
7909
** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
7910
** ^Objects of this type are created by [sqlite3_blob_open()]
7911
** and destroyed by [sqlite3_blob_close()].
7912
** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
7913
** can be used to read or write small subsections of the BLOB.
7914
** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
7915
*/
7916
typedef struct sqlite3_blob sqlite3_blob;
7917
7918
/*
7919
** CAPI3REF: Open A BLOB For Incremental I/O
7920
** METHOD: sqlite3
7921
** CONSTRUCTOR: sqlite3_blob
7922
**
7923
** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
7924
** in row iRow, column zColumn, table zTable in database zDb;
7925
** in other words, the same BLOB that would be selected by:
7926
**
7927
** <pre>
7928
**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
7929
** </pre>)^
7930
**
7931
** ^(Parameter zDb is not the filename that contains the database, but
7932
** rather the symbolic name of the database. For attached databases, this is
7933
** the name that appears after the AS keyword in the [ATTACH] statement.
7934
** For the main database file, the database name is "main". For TEMP
7935
** tables, the database name is "temp".)^
7936
**
7937
** ^If the flags parameter is non-zero, then the BLOB is opened for read
7938
** and write access. ^If the flags parameter is zero, the BLOB is opened for
7939
** read-only access.
7940
**
7941
** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
7942
** in *ppBlob. Otherwise an [error code] is returned and, unless the error
7943
** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
7944
** the API is not misused, it is always safe to call [sqlite3_blob_close()]
7945
** on *ppBlob after this function returns.
7946
**
7947
** This function fails with SQLITE_ERROR if any of the following are true:
7948
** <ul>
7949
**   <li> ^(Database zDb does not exist)^,
7950
**   <li> ^(Table zTable does not exist within database zDb)^,
7951
**   <li> ^(Table zTable is a WITHOUT ROWID table)^,
7952
**   <li> ^(Column zColumn does not exist)^,
7953
**   <li> ^(Row iRow is not present in the table)^,
7954
**   <li> ^(The specified column of row iRow contains a value that is not
7955
**         a TEXT or BLOB value)^,
7956
**   <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
7957
**         constraint and the blob is being opened for read/write access)^,
7958
**   <li> ^([foreign key constraints | Foreign key constraints] are enabled,
7959
**         column zColumn is part of a [child key] definition and the blob is
7960
**         being opened for read/write access)^.
7961
** </ul>
7962
**
7963
** ^Unless it returns SQLITE_MISUSE, this function sets the
7964
** [database connection] error code and message accessible via
7965
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
7966
**
7967
** A BLOB referenced by sqlite3_blob_open() may be read using the
7968
** [sqlite3_blob_read()] interface and modified by using
7969
** [sqlite3_blob_write()].  The [BLOB handle] can be moved to a
7970
** different row of the same table using the [sqlite3_blob_reopen()]
7971
** interface.  However, the column, table, or database of a [BLOB handle]
7972
** cannot be changed after the [BLOB handle] is opened.
7973
**
7974
** ^(If the row that a BLOB handle points to is modified by an
7975
** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
7976
** then the BLOB handle is marked as "expired".
7977
** This is true if any column of the row is changed, even a column
7978
** other than the one the BLOB handle is open on.)^
7979
** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
7980
** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
7981
** ^(Changes written into a BLOB prior to the BLOB expiring are not
7982
** rolled back by the expiration of the BLOB.  Such changes will eventually
7983
** commit if the transaction continues to completion.)^
7984
**
7985
** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
7986
** the opened blob.  ^The size of a blob may not be changed by this
7987
** interface.  Use the [UPDATE] SQL command to change the size of a
7988
** blob.
7989
**
7990
** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
7991
** and the built-in [zeroblob] SQL function may be used to create a
7992
** zero-filled blob to read or write using the incremental-blob interface.
7993
**
7994
** To avoid a resource leak, every open [BLOB handle] should eventually
7995
** be released by a call to [sqlite3_blob_close()].
7996
**
7997
** See also: [sqlite3_blob_close()],
7998
** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
7999
** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
8000
*/
8001
SQLITE_API int sqlite3_blob_open(
8002
  sqlite3*,
8003
  const char *zDb,
8004
  const char *zTable,
8005
  const char *zColumn,
8006
  sqlite3_int64 iRow,
8007
  int flags,
8008
  sqlite3_blob **ppBlob
8009
);
8010
8011
/*
8012
** CAPI3REF: Move a BLOB Handle to a New Row
8013
** METHOD: sqlite3_blob
8014
**
8015
** ^This function is used to move an existing [BLOB handle] so that it points
8016
** to a different row of the same database table. ^The new row is identified
8017
** by the rowid value passed as the second argument. Only the row can be
8018
** changed. ^The database, table and column on which the blob handle is open
8019
** remain the same. Moving an existing [BLOB handle] to a new row is
8020
** faster than closing the existing handle and opening a new one.
8021
**
8022
** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
8023
** it must exist and there must be either a blob or text value stored in
8024
** the nominated column.)^ ^If the new row is not present in the table, or if
8025
** it does not contain a blob or text value, or if another error occurs, an
8026
** SQLite error code is returned and the blob handle is considered aborted.
8027
** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
8028
** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
8029
** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
8030
** always returns zero.
8031
**
8032
** ^This function sets the database handle error code and message.
8033
*/
8034
SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
8035
8036
/*
8037
** CAPI3REF: Close A BLOB Handle
8038
** DESTRUCTOR: sqlite3_blob
8039
**
8040
** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
8041
** unconditionally.  Even if this routine returns an error code, the
8042
** handle is still closed.)^
8043
**
8044
** ^If the blob handle being closed was opened for read-write access, and if
8045
** the database is in auto-commit mode and there are no other open read-write
8046
** blob handles or active write statements, the current transaction is
8047
** committed. ^If an error occurs while committing the transaction, an error
8048
** code is returned and the transaction rolled back.
8049
**
8050
** Calling this function with an argument that is not a NULL pointer or an
8051
** open blob handle results in undefined behavior. ^Calling this routine
8052
** with a null pointer (such as would be returned by a failed call to
8053
** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
8054
** is passed a valid open blob handle, the values returned by the
8055
** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
8056
*/
8057
SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
8058
8059
/*
8060
** CAPI3REF: Return The Size Of An Open BLOB
8061
** METHOD: sqlite3_blob
8062
**
8063
** ^Returns the size in bytes of the BLOB accessible via the
8064
** successfully opened [BLOB handle] in its only argument.  ^The
8065
** incremental blob I/O routines can only read or overwrite existing
8066
** blob content; they cannot change the size of a blob.
8067
**
8068
** This routine only works on a [BLOB handle] which has been created
8069
** by a prior successful call to [sqlite3_blob_open()] and which has not
8070
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
8071
** to this routine results in undefined and probably undesirable behavior.
8072
*/
8073
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
8074
8075
/*
8076
** CAPI3REF: Read Data From A BLOB Incrementally
8077
** METHOD: sqlite3_blob
8078
**
8079
** ^(This function is used to read data from an open [BLOB handle] into a
8080
** caller-supplied buffer. N bytes of data are copied into buffer Z
8081
** from the open BLOB, starting at offset iOffset.)^
8082
**
8083
** ^If offset iOffset is less than N bytes from the end of the BLOB,
8084
** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
8085
** less than zero, [SQLITE_ERROR] is returned and no data is read.
8086
** ^The size of the blob (and hence the maximum value of N+iOffset)
8087
** can be determined using the [sqlite3_blob_bytes()] interface.
8088
**
8089
** ^An attempt to read from an expired [BLOB handle] fails with an
8090
** error code of [SQLITE_ABORT].
8091
**
8092
** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
8093
** Otherwise, an [error code] or an [extended error code] is returned.)^
8094
**
8095
** This routine only works on a [BLOB handle] which has been created
8096
** by a prior successful call to [sqlite3_blob_open()] and which has not
8097
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
8098
** to this routine results in undefined and probably undesirable behavior.
8099
**
8100
** See also: [sqlite3_blob_write()].
8101
*/
8102
SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
8103
8104
/*
8105
** CAPI3REF: Write Data Into A BLOB Incrementally
8106
** METHOD: sqlite3_blob
8107
**
8108
** ^(This function is used to write data into an open [BLOB handle] from a
8109
** caller-supplied buffer. N bytes of data are copied from the buffer Z
8110
** into the open BLOB, starting at offset iOffset.)^
8111
**
8112
** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
8113
** Otherwise, an  [error code] or an [extended error code] is returned.)^
8114
** ^Unless SQLITE_MISUSE is returned, this function sets the
8115
** [database connection] error code and message accessible via
8116
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
8117
**
8118
** ^If the [BLOB handle] passed as the first argument was not opened for
8119
** writing (the flags parameter to [sqlite3_blob_open()] was zero),
8120
** this function returns [SQLITE_READONLY].
8121
**
8122
** This function may only modify the contents of the BLOB; it is
8123
** not possible to increase the size of a BLOB using this API.
8124
** ^If offset iOffset is less than N bytes from the end of the BLOB,
8125
** [SQLITE_ERROR] is returned and no data is written. The size of the
8126
** BLOB (and hence the maximum value of N+iOffset) can be determined
8127
** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
8128
** than zero [SQLITE_ERROR] is returned and no data is written.
8129
**
8130
** ^An attempt to write to an expired [BLOB handle] fails with an
8131
** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
8132
** before the [BLOB handle] expired are not rolled back by the
8133
** expiration of the handle, though of course those changes might
8134
** have been overwritten by the statement that expired the BLOB handle
8135
** or by other independent statements.
8136
**
8137
** This routine only works on a [BLOB handle] which has been created
8138
** by a prior successful call to [sqlite3_blob_open()] and which has not
8139
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
8140
** to this routine results in undefined and probably undesirable behavior.
8141
**
8142
** See also: [sqlite3_blob_read()].
8143
*/
8144
SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
8145
8146
/*
8147
** CAPI3REF: Virtual File System Objects
8148
**
8149
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
8150
** that SQLite uses to interact
8151
** with the underlying operating system.  Most SQLite builds come with a
8152
** single default VFS that is appropriate for the host computer.
8153
** New VFSes can be registered and existing VFSes can be unregistered.
8154
** The following interfaces are provided.
8155
**
8156
** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
8157
** ^Names are case sensitive.
8158
** ^Names are zero-terminated UTF-8 strings.
8159
** ^If there is no match, a NULL pointer is returned.
8160
** ^If zVfsName is NULL then the default VFS is returned.
8161
**
8162
** ^New VFSes are registered with sqlite3_vfs_register().
8163
** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
8164
** ^The same VFS can be registered multiple times without injury.
8165
** ^To make an existing VFS into the default VFS, register it again
8166
** with the makeDflt flag set.  If two different VFSes with the
8167
** same name are registered, the behavior is undefined.  If a
8168
** VFS is registered with a name that is NULL or an empty string,
8169
** then the behavior is undefined.
8170
**
8171
** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
8172
** ^(If the default VFS is unregistered, another VFS is chosen as
8173
** the default.  The choice for the new VFS is arbitrary.)^
8174
*/
8175
SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
8176
SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
8177
SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
8178
8179
/*
8180
** CAPI3REF: Mutexes
8181
**
8182
** The SQLite core uses these routines for thread
8183
** synchronization. Though they are intended for internal
8184
** use by SQLite, code that links against SQLite is
8185
** permitted to use any of these routines.
8186
**
8187
** The SQLite source code contains multiple implementations
8188
** of these mutex routines.  An appropriate implementation
8189
** is selected automatically at compile-time.  The following
8190
** implementations are available in the SQLite core:
8191
**
8192
** <ul>
8193
** <li>   SQLITE_MUTEX_PTHREADS
8194
** <li>   SQLITE_MUTEX_W32
8195
** <li>   SQLITE_MUTEX_NOOP
8196
** </ul>
8197
**
8198
** The SQLITE_MUTEX_NOOP implementation is a set of routines
8199
** that does no real locking and is appropriate for use in
8200
** a single-threaded application.  The SQLITE_MUTEX_PTHREADS and
8201
** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
8202
** and Windows.
8203
**
8204
** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
8205
** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
8206
** implementation is included with the library. In this case the
8207
** application must supply a custom mutex implementation using the
8208
** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
8209
** before calling sqlite3_initialize() or any other public sqlite3_
8210
** function that calls sqlite3_initialize().
8211
**
8212
** ^The sqlite3_mutex_alloc() routine allocates a new
8213
** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
8214
** routine returns NULL if it is unable to allocate the requested
8215
** mutex.  The argument to sqlite3_mutex_alloc() must be one of these
8216
** integer constants:
8217
**
8218
** <ul>
8219
** <li>  SQLITE_MUTEX_FAST
8220
** <li>  SQLITE_MUTEX_RECURSIVE
8221
** <li>  SQLITE_MUTEX_STATIC_MAIN
8222
** <li>  SQLITE_MUTEX_STATIC_MEM
8223
** <li>  SQLITE_MUTEX_STATIC_OPEN
8224
** <li>  SQLITE_MUTEX_STATIC_PRNG
8225
** <li>  SQLITE_MUTEX_STATIC_LRU
8226
** <li>  SQLITE_MUTEX_STATIC_PMEM
8227
** <li>  SQLITE_MUTEX_STATIC_APP1
8228
** <li>  SQLITE_MUTEX_STATIC_APP2
8229
** <li>  SQLITE_MUTEX_STATIC_APP3
8230
** <li>  SQLITE_MUTEX_STATIC_VFS1
8231
** <li>  SQLITE_MUTEX_STATIC_VFS2
8232
** <li>  SQLITE_MUTEX_STATIC_VFS3
8233
** </ul>
8234
**
8235
** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
8236
** cause sqlite3_mutex_alloc() to create
8237
** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
8238
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
8239
** The mutex implementation does not need to make a distinction
8240
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
8241
** not want to.  SQLite will only request a recursive mutex in
8242
** cases where it really needs one.  If a faster non-recursive mutex
8243
** implementation is available on the host platform, the mutex subsystem
8244
** might return such a mutex in response to SQLITE_MUTEX_FAST.
8245
**
8246
** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
8247
** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
8248
** a pointer to a static preexisting mutex.  ^Nine static mutexes are
8249
** used by the current version of SQLite.  Future versions of SQLite
8250
** may add additional static mutexes.  Static mutexes are for internal
8251
** use by SQLite only.  Applications that use SQLite mutexes should
8252
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
8253
** SQLITE_MUTEX_RECURSIVE.
8254
**
8255
** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
8256
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
8257
** returns a different mutex on every call.  ^For the static
8258
** mutex types, the same mutex is returned on every call that has
8259
** the same type number.
8260
**
8261
** ^The sqlite3_mutex_free() routine deallocates a previously
8262
** allocated dynamic mutex.  Attempting to deallocate a static
8263
** mutex results in undefined behavior.
8264
**
8265
** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
8266
** to enter a mutex.  ^If another thread is already within the mutex,
8267
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
8268
** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
8269
** upon successful entry.  ^(Mutexes created using
8270
** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
8271
** In such cases, the
8272
** mutex must be exited an equal number of times before another thread
8273
** can enter.)^  If the same thread tries to enter any mutex other
8274
** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
8275
**
8276
** ^(Some systems (for example, Windows 95) do not support the operation
8277
** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
8278
** will always return SQLITE_BUSY. In most cases the SQLite core only uses
8279
** sqlite3_mutex_try() as an optimization, so this is acceptable
8280
** behavior. The exceptions are unix builds that set the
8281
** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working
8282
** sqlite3_mutex_try() is required.)^
8283
**
8284
** ^The sqlite3_mutex_leave() routine exits a mutex that was
8285
** previously entered by the same thread.   The behavior
8286
** is undefined if the mutex is not currently entered by the
8287
** calling thread or is not currently allocated.
8288
**
8289
** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(),
8290
** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer,
8291
** then any of the four routines behaves as a no-op.
8292
**
8293
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
8294
*/
8295
SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
8296
SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
8297
SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
8298
SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
8299
SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
8300
8301
/*
8302
** CAPI3REF: Mutex Methods Object
8303
**
8304
** An instance of this structure defines the low-level routines
8305
** used to allocate and use mutexes.
8306
**
8307
** Usually, the default mutex implementations provided by SQLite are
8308
** sufficient, however the application has the option of substituting a custom
8309
** implementation for specialized deployments or systems for which SQLite
8310
** does not provide a suitable implementation. In this case, the application
8311
** creates and populates an instance of this structure to pass
8312
** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
8313
** Additionally, an instance of this structure can be used as an
8314
** output variable when querying the system for the current mutex
8315
** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
8316
**
8317
** ^The xMutexInit method defined by this structure is invoked as
8318
** part of system initialization by the sqlite3_initialize() function.
8319
** ^The xMutexInit routine is called by SQLite exactly once for each
8320
** effective call to [sqlite3_initialize()].
8321
**
8322
** ^The xMutexEnd method defined by this structure is invoked as
8323
** part of system shutdown by the sqlite3_shutdown() function. The
8324
** implementation of this method is expected to release all outstanding
8325
** resources obtained by the mutex methods implementation, especially
8326
** those obtained by the xMutexInit method.  ^The xMutexEnd()
8327
** interface is invoked exactly once for each call to [sqlite3_shutdown()].
8328
**
8329
** ^(The remaining seven methods defined by this structure (xMutexAlloc,
8330
** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
8331
** xMutexNotheld) implement the following interfaces (respectively):
8332
**
8333
** <ul>
8334
**   <li>  [sqlite3_mutex_alloc()] </li>
8335
**   <li>  [sqlite3_mutex_free()] </li>
8336
**   <li>  [sqlite3_mutex_enter()] </li>
8337
**   <li>  [sqlite3_mutex_try()] </li>
8338
**   <li>  [sqlite3_mutex_leave()] </li>
8339
**   <li>  [sqlite3_mutex_held()] </li>
8340
**   <li>  [sqlite3_mutex_notheld()] </li>
8341
** </ul>)^
8342
**
8343
** The only difference is that the public sqlite3_XXX functions enumerated
8344
** above silently ignore any invocations that pass a NULL pointer instead
8345
** of a valid mutex handle. The implementations of the methods defined
8346
** by this structure are not required to handle this case. The results
8347
** of passing a NULL pointer instead of a valid mutex handle are undefined
8348
** (i.e. it is acceptable to provide an implementation that segfaults if
8349
** it is passed a NULL pointer).
8350
**
8351
** The xMutexInit() method must be threadsafe.  It must be harmless to
8352
** invoke xMutexInit() multiple times within the same process and without
8353
** intervening calls to xMutexEnd().  Second and subsequent calls to
8354
** xMutexInit() must be no-ops.
8355
**
8356
** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
8357
** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
8358
** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
8359
** memory allocation for a fast or recursive mutex.
8360
**
8361
** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
8362
** called, but only if the prior call to xMutexInit returned SQLITE_OK.
8363
** If xMutexInit fails in any way, it is expected to clean up after itself
8364
** prior to returning.
8365
*/
8366
typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
8367
struct sqlite3_mutex_methods {
8368
  int (*xMutexInit)(void);
8369
  int (*xMutexEnd)(void);
8370
  sqlite3_mutex *(*xMutexAlloc)(int);
8371
  void (*xMutexFree)(sqlite3_mutex *);
8372
  void (*xMutexEnter)(sqlite3_mutex *);
8373
  int (*xMutexTry)(sqlite3_mutex *);
8374
  void (*xMutexLeave)(sqlite3_mutex *);
8375
  int (*xMutexHeld)(sqlite3_mutex *);
8376
  int (*xMutexNotheld)(sqlite3_mutex *);
8377
};
8378
8379
/*
8380
** CAPI3REF: Mutex Verification Routines
8381
**
8382
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
8383
** are intended for use inside assert() statements.  The SQLite core
8384
** never uses these routines except inside an assert() and applications
8385
** are advised to follow the lead of the core.  The SQLite core only
8386
** provides implementations for these routines when it is compiled
8387
** with the SQLITE_DEBUG flag.  External mutex implementations
8388
** are only required to provide these routines if SQLITE_DEBUG is
8389
** defined and if NDEBUG is not defined.
8390
**
8391
** These routines should return true if the mutex in their argument
8392
** is held or not held, respectively, by the calling thread.
8393
**
8394
** The implementation is not required to provide versions of these
8395
** routines that actually work. If the implementation does not provide working
8396
** versions of these routines, it should at least provide stubs that always
8397
** return true so that one does not get spurious assertion failures.
8398
**
8399
** If the argument to sqlite3_mutex_held() is a NULL pointer then
8400
** the routine should return 1.   This seems counter-intuitive since
8401
** clearly the mutex cannot be held if it does not exist.  But
8402
** the reason the mutex does not exist is because the build is not
8403
** using mutexes.  And we do not want the assert() containing the
8404
** call to sqlite3_mutex_held() to fail, so a non-zero return is
8405
** the appropriate thing to do.  The sqlite3_mutex_notheld()
8406
** interface should also return 1 when given a NULL pointer.
8407
*/
8408
#ifndef NDEBUG
8409
SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
8410
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
8411
#endif
8412
8413
/*
8414
** CAPI3REF: Mutex Types
8415
**
8416
** The [sqlite3_mutex_alloc()] interface takes a single argument
8417
** which is one of these integer constants.
8418
**
8419
** The set of static mutexes may change from one SQLite release to the
8420
** next.  Applications that override the built-in mutex logic must be
8421
** prepared to accommodate additional static mutexes.
8422
*/
8423
#define SQLITE_MUTEX_FAST             0
8424
#define SQLITE_MUTEX_RECURSIVE        1
8425
#define SQLITE_MUTEX_STATIC_MAIN      2
8426
#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
8427
#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
8428
#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
8429
#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_randomness() */
8430
#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
8431
#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
8432
#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
8433
#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
8434
#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
8435
#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
8436
#define SQLITE_MUTEX_STATIC_VFS1     11  /* For use by built-in VFS */
8437
#define SQLITE_MUTEX_STATIC_VFS2     12  /* For use by extension VFS */
8438
#define SQLITE_MUTEX_STATIC_VFS3     13  /* For use by application VFS */
8439
8440
/* Legacy compatibility: */
8441
#define SQLITE_MUTEX_STATIC_MASTER    2
8442
8443
8444
/*
8445
** CAPI3REF: Retrieve the mutex for a database connection
8446
** METHOD: sqlite3
8447
**
8448
** ^This interface returns a pointer to the [sqlite3_mutex] object that
8449
** serializes access to the [database connection] given in the argument
8450
** when the [threading mode] is Serialized.
8451
** ^If the [threading mode] is Single-thread or Multi-thread then this
8452
** routine returns a NULL pointer.
8453
*/
8454
SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
8455
8456
/*
8457
** CAPI3REF: Low-Level Control Of Database Files
8458
** METHOD: sqlite3
8459
** KEYWORDS: {file control}
8460
**
8461
** ^The [sqlite3_file_control()] interface makes a direct call to the
8462
** xFileControl method for the [sqlite3_io_methods] object associated
8463
** with a particular database identified by the second argument. ^The
8464
** name of the database is "main" for the main database or "temp" for the
8465
** TEMP database, or the name that appears after the AS keyword for
8466
** databases that are added using the [ATTACH] SQL command.
8467
** ^A NULL pointer can be used in place of "main" to refer to the
8468
** main database file.
8469
** ^The third and fourth parameters to this routine
8470
** are passed directly through to the second and third parameters of
8471
** the xFileControl method.  ^The return value of the xFileControl
8472
** method becomes the return value of this routine.
8473
**
8474
** A few opcodes for [sqlite3_file_control()] are handled directly
8475
** by the SQLite core and never invoke the
8476
** sqlite3_io_methods.xFileControl method.
8477
** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
8478
** a pointer to the underlying [sqlite3_file] object to be written into
8479
** the space pointed to by the 4th parameter.  The
8480
** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
8481
** the [sqlite3_file] object associated with the journal file instead of
8482
** the main database.  The [SQLITE_FCNTL_VFS_POINTER] opcode returns
8483
** a pointer to the underlying [sqlite3_vfs] object for the file.
8484
** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
8485
** from the pager.
8486
**
8487
** ^If the second parameter (zDbName) does not match the name of any
8488
** open database file, then SQLITE_ERROR is returned.  ^This error
8489
** code is not remembered and will not be recalled by [sqlite3_errcode()]
8490
** or [sqlite3_errmsg()].  The underlying xFileControl method might
8491
** also return SQLITE_ERROR.  There is no way to distinguish between
8492
** an incorrect zDbName and an SQLITE_ERROR return from the underlying
8493
** xFileControl method.
8494
**
8495
** See also: [file control opcodes]
8496
*/
8497
SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
8498
8499
/*
8500
** CAPI3REF: Testing Interface
8501
**
8502
** ^The sqlite3_test_control() interface is used to read out internal
8503
** state of SQLite and to inject faults into SQLite for testing
8504
** purposes.  ^The first parameter is an operation code that determines
8505
** the number, meaning, and operation of all subsequent parameters.
8506
**
8507
** This interface is not for use by applications.  It exists solely
8508
** for verifying the correct operation of the SQLite library.  Depending
8509
** on how the SQLite library is compiled, this interface might not exist.
8510
**
8511
** The details of the operation codes, their meanings, the parameters
8512
** they take, and what they do are all subject to change without notice.
8513
** Unlike most of the SQLite API, this function is not guaranteed to
8514
** operate consistently from one release to the next.
8515
*/
8516
SQLITE_API int sqlite3_test_control(int op, ...);
8517
8518
/*
8519
** CAPI3REF: Testing Interface Operation Codes
8520
**
8521
** These constants are the valid operation code parameters used
8522
** as the first argument to [sqlite3_test_control()].
8523
**
8524
** These parameters and their meanings are subject to change
8525
** without notice.  These values are for testing purposes only.
8526
** Applications should not use any of these parameters or the
8527
** [sqlite3_test_control()] interface.
8528
*/
8529
#define SQLITE_TESTCTRL_FIRST                    5
8530
#define SQLITE_TESTCTRL_PRNG_SAVE                5
8531
#define SQLITE_TESTCTRL_PRNG_RESTORE             6
8532
#define SQLITE_TESTCTRL_PRNG_RESET               7  /* NOT USED */
8533
#define SQLITE_TESTCTRL_FK_NO_ACTION             7
8534
#define SQLITE_TESTCTRL_BITVEC_TEST              8
8535
#define SQLITE_TESTCTRL_FAULT_INSTALL            9
8536
#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
8537
#define SQLITE_TESTCTRL_PENDING_BYTE            11
8538
#define SQLITE_TESTCTRL_ASSERT                  12
8539
#define SQLITE_TESTCTRL_ALWAYS                  13
8540
#define SQLITE_TESTCTRL_RESERVE                 14  /* NOT USED */
8541
#define SQLITE_TESTCTRL_JSON_SELFCHECK          14
8542
#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
8543
#define SQLITE_TESTCTRL_ISKEYWORD               16  /* NOT USED */
8544
#define SQLITE_TESTCTRL_GETOPT                  16
8545
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17  /* NOT USED */
8546
#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS      17
8547
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
8548
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
8549
#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD    19
8550
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
8551
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
8552
#define SQLITE_TESTCTRL_BYTEORDER               22
8553
#define SQLITE_TESTCTRL_ISINIT                  23
8554
#define SQLITE_TESTCTRL_SORTER_MMAP             24
8555
#define SQLITE_TESTCTRL_IMPOSTER                25
8556
#define SQLITE_TESTCTRL_PARSER_COVERAGE         26
8557
#define SQLITE_TESTCTRL_RESULT_INTREAL          27
8558
#define SQLITE_TESTCTRL_PRNG_SEED               28
8559
#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS     29
8560
#define SQLITE_TESTCTRL_SEEK_COUNT              30
8561
#define SQLITE_TESTCTRL_TRACEFLAGS              31
8562
#define SQLITE_TESTCTRL_TUNE                    32
8563
#define SQLITE_TESTCTRL_LOGEST                  33
8564
#define SQLITE_TESTCTRL_USELONGDOUBLE           34  /* NOT USED */
8565
#define SQLITE_TESTCTRL_LAST                    34  /* Largest TESTCTRL */
8566
8567
/*
8568
** CAPI3REF: SQL Keyword Checking
8569
**
8570
** These routines provide access to the set of SQL language keywords
8571
** recognized by SQLite.  Applications can use these routines to determine
8572
** whether or not a specific identifier needs to be escaped (for example,
8573
** by enclosing in double-quotes) so as not to confuse the parser.
8574
**
8575
** The sqlite3_keyword_count() interface returns the number of distinct
8576
** keywords understood by SQLite.
8577
**
8578
** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and
8579
** makes *Z point to that keyword expressed as UTF8 and writes the number
8580
** of bytes in the keyword into *L.  The string that *Z points to is not
8581
** zero-terminated.  The sqlite3_keyword_name(N,Z,L) routine returns
8582
** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
8583
** or L are NULL or invalid pointers then calls to
8584
** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
8585
**
8586
** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
8587
** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
8588
** if it is and zero if not.
8589
**
8590
** The parser used by SQLite is forgiving.  It is often possible to use
8591
** a keyword as an identifier as long as such use does not result in a
8592
** parsing ambiguity.  For example, the statement
8593
** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
8594
** creates a new table named "BEGIN" with three columns named
8595
** "REPLACE", "PRAGMA", and "END".  Nevertheless, best practice is to avoid
8596
** using keywords as identifiers.  Common techniques used to avoid keyword
8597
** name collisions include:
8598
** <ul>
8599
** <li> Put all identifier names inside double-quotes.  This is the official
8600
**      SQL way to escape identifier names.
8601
** <li> Put identifier names inside &#91;...&#93;.  This is not standard SQL,
8602
**      but it is what SQL Server does and so lots of programmers use this
8603
**      technique.
8604
** <li> Begin every identifier with the letter "Z" as no SQL keywords start
8605
**      with "Z".
8606
** <li> Include a digit somewhere in every identifier name.
8607
** </ul>
8608
**
8609
** Note that the number of keywords understood by SQLite can depend on
8610
** compile-time options.  For example, "VACUUM" is not a keyword if
8611
** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option.  Also,
8612
** new keywords may be added to future releases of SQLite.
8613
*/
8614
SQLITE_API int sqlite3_keyword_count(void);
8615
SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
8616
SQLITE_API int sqlite3_keyword_check(const char*,int);
8617
8618
/*
8619
** CAPI3REF: Dynamic String Object
8620
** KEYWORDS: {dynamic string}
8621
**
8622
** An instance of the sqlite3_str object contains a dynamically-sized
8623
** string under construction.
8624
**
8625
** The lifecycle of an sqlite3_str object is as follows:
8626
** <ol>
8627
** <li> ^The sqlite3_str object is created using [sqlite3_str_new()].
8628
** <li> ^Text is appended to the sqlite3_str object using various
8629
** methods, such as [sqlite3_str_appendf()].
8630
** <li> ^The sqlite3_str object is destroyed and the string it created
8631
** is returned using the [sqlite3_str_finish()] interface.
8632
** </ol>
8633
*/
8634
typedef struct sqlite3_str sqlite3_str;
8635
8636
/*
8637
** CAPI3REF: Create A New Dynamic String Object
8638
** CONSTRUCTOR: sqlite3_str
8639
**
8640
** ^The [sqlite3_str_new(D)] interface allocates and initializes
8641
** a new [sqlite3_str] object.  To avoid memory leaks, the object returned by
8642
** [sqlite3_str_new()] must be freed by a subsequent call to
8643
** [sqlite3_str_finish(X)].
8644
**
8645
** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
8646
** valid [sqlite3_str] object, though in the event of an out-of-memory
8647
** error the returned object might be a special singleton that will
8648
** silently reject new text, always return SQLITE_NOMEM from
8649
** [sqlite3_str_errcode()], always return 0 for
8650
** [sqlite3_str_length()], and always return NULL from
8651
** [sqlite3_str_finish(X)].  It is always safe to use the value
8652
** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
8653
** to any of the other [sqlite3_str] methods.
8654
**
8655
** The D parameter to [sqlite3_str_new(D)] may be NULL.  If the
8656
** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
8657
** length of the string contained in the [sqlite3_str] object will be
8658
** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
8659
** of [SQLITE_MAX_LENGTH].
8660
*/
8661
SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
8662
8663
/*
8664
** CAPI3REF: Finalize A Dynamic String
8665
** DESTRUCTOR: sqlite3_str
8666
**
8667
** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
8668
** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
8669
** that contains the constructed string.  The calling application should
8670
** pass the returned value to [sqlite3_free()] to avoid a memory leak.
8671
** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
8672
** errors were encountered during construction of the string.  ^The
8673
** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the
8674
** string in [sqlite3_str] object X is zero bytes long.
8675
*/
8676
SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
8677
8678
/*
8679
** CAPI3REF: Add Content To A Dynamic String
8680
** METHOD: sqlite3_str
8681
**
8682
** These interfaces add content to an sqlite3_str object previously obtained
8683
** from [sqlite3_str_new()].
8684
**
8685
** ^The [sqlite3_str_appendf(X,F,...)] and
8686
** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
8687
** functionality of SQLite to append formatted text onto the end of
8688
** [sqlite3_str] object X.
8689
**
8690
** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
8691
** onto the end of the [sqlite3_str] object X.  N must be non-negative.
8692
** S must contain at least N non-zero bytes of content.  To append a
8693
** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
8694
** method instead.
8695
**
8696
** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
8697
** zero-terminated string S onto the end of [sqlite3_str] object X.
8698
**
8699
** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
8700
** single-byte character C onto the end of [sqlite3_str] object X.
8701
** ^This method can be used, for example, to add whitespace indentation.
8702
**
8703
** ^The [sqlite3_str_reset(X)] method resets the string under construction
8704
** inside [sqlite3_str] object X back to zero bytes in length.
8705
**
8706
** These methods do not return a result code.  ^If an error occurs, that fact
8707
** is recorded in the [sqlite3_str] object and can be recovered by a
8708
** subsequent call to [sqlite3_str_errcode(X)].
8709
*/
8710
SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
8711
SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list);
8712
SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N);
8713
SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn);
8714
SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C);
8715
SQLITE_API void sqlite3_str_reset(sqlite3_str*);
8716
8717
/*
8718
** CAPI3REF: Status Of A Dynamic String
8719
** METHOD: sqlite3_str
8720
**
8721
** These interfaces return the current status of an [sqlite3_str] object.
8722
**
8723
** ^If any prior errors have occurred while constructing the dynamic string
8724
** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return
8725
** an appropriate error code.  ^The [sqlite3_str_errcode(X)] method returns
8726
** [SQLITE_NOMEM] following any out-of-memory error, or
8727
** [SQLITE_TOOBIG] if the size of the dynamic string exceeds
8728
** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors.
8729
**
8730
** ^The [sqlite3_str_length(X)] method returns the current length, in bytes,
8731
** of the dynamic string under construction in [sqlite3_str] object X.
8732
** ^The length returned by [sqlite3_str_length(X)] does not include the
8733
** zero-termination byte.
8734
**
8735
** ^The [sqlite3_str_value(X)] method returns a pointer to the current
8736
** content of the dynamic string under construction in X.  The value
8737
** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X
8738
** and might be freed or altered by any subsequent method on the same
8739
** [sqlite3_str] object.  Applications must not use the pointer returned by
8740
** [sqlite3_str_value(X)] after any subsequent method call on the same
8741
** object.  ^Applications may change the content of the string returned
8742
** by [sqlite3_str_value(X)] as long as they do not write into any bytes
8743
** outside the range of 0 to [sqlite3_str_length(X)] and do not read or
8744
** write any byte after any subsequent sqlite3_str method call.
8745
*/
8746
SQLITE_API int sqlite3_str_errcode(sqlite3_str*);
8747
SQLITE_API int sqlite3_str_length(sqlite3_str*);
8748
SQLITE_API char *sqlite3_str_value(sqlite3_str*);
8749
8750
/*
8751
** CAPI3REF: SQLite Runtime Status
8752
**
8753
** ^These interfaces are used to retrieve runtime status information
8754
** about the performance of SQLite, and optionally to reset various
8755
** highwater marks.  ^The first argument is an integer code for
8756
** the specific parameter to measure.  ^(Recognized integer codes
8757
** are of the form [status parameters | SQLITE_STATUS_...].)^
8758
** ^The current value of the parameter is returned into *pCurrent.
8759
** ^The highest recorded value is returned in *pHighwater.  ^If the
8760
** resetFlag is true, then the highest record value is reset after
8761
** *pHighwater is written.  ^(Some parameters do not record the highest
8762
** value.  For those parameters
8763
** nothing is written into *pHighwater and the resetFlag is ignored.)^
8764
** ^(Other parameters record only the highwater mark and not the current
8765
** value.  For these latter parameters nothing is written into *pCurrent.)^
8766
**
8767
** ^The sqlite3_status() and sqlite3_status64() routines return
8768
** SQLITE_OK on success and a non-zero [error code] on failure.
8769
**
8770
** If either the current value or the highwater mark is too large to
8771
** be represented by a 32-bit integer, then the values returned by
8772
** sqlite3_status() are undefined.
8773
**
8774
** See also: [sqlite3_db_status()]
8775
*/
8776
SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
8777
SQLITE_API int sqlite3_status64(
8778
  int op,
8779
  sqlite3_int64 *pCurrent,
8780
  sqlite3_int64 *pHighwater,
8781
  int resetFlag
8782
);
8783
8784
8785
/*
8786
** CAPI3REF: Status Parameters
8787
** KEYWORDS: {status parameters}
8788
**
8789
** These integer constants designate various run-time status parameters
8790
** that can be returned by [sqlite3_status()].
8791
**
8792
** <dl>
8793
** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
8794
** <dd>This parameter is the current amount of memory checked out
8795
** using [sqlite3_malloc()], either directly or indirectly.  The
8796
** figure includes calls made to [sqlite3_malloc()] by the application
8797
** and internal memory usage by the SQLite library.  Auxiliary page-cache
8798
** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
8799
** this parameter.  The amount returned is the sum of the allocation
8800
** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
8801
**
8802
** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
8803
** <dd>This parameter records the largest memory allocation request
8804
** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
8805
** internal equivalents).  Only the value returned in the
8806
** *pHighwater parameter to [sqlite3_status()] is of interest.
8807
** The value written into the *pCurrent parameter is undefined.</dd>)^
8808
**
8809
** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
8810
** <dd>This parameter records the number of separate memory allocations
8811
** currently checked out.</dd>)^
8812
**
8813
** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
8814
** <dd>This parameter returns the number of pages used out of the
8815
** [pagecache memory allocator] that was configured using
8816
** [SQLITE_CONFIG_PAGECACHE].  The
8817
** value returned is in pages, not in bytes.</dd>)^
8818
**
8819
** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
8820
** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
8821
** <dd>This parameter returns the number of bytes of page cache
8822
** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
8823
** buffer and where forced to overflow to [sqlite3_malloc()].  The
8824
** returned value includes allocations that overflowed because they
8825
** were too large (they were larger than the "sz" parameter to
8826
** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
8827
** no space was left in the page cache.</dd>)^
8828
**
8829
** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
8830
** <dd>This parameter records the largest memory allocation request
8831
** handed to the [pagecache memory allocator].  Only the value returned in the
8832
** *pHighwater parameter to [sqlite3_status()] is of interest.
8833
** The value written into the *pCurrent parameter is undefined.</dd>)^
8834
**
8835
** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt>
8836
** <dd>No longer used.</dd>
8837
**
8838
** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
8839
** <dd>No longer used.</dd>
8840
**
8841
** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
8842
** <dd>No longer used.</dd>
8843
**
8844
** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
8845
** <dd>The *pHighwater parameter records the deepest parser stack.
8846
** The *pCurrent value is undefined.  The *pHighwater value is only
8847
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
8848
** </dl>
8849
**
8850
** New status parameters may be added from time to time.
8851
*/
8852
#define SQLITE_STATUS_MEMORY_USED          0
8853
#define SQLITE_STATUS_PAGECACHE_USED       1
8854
#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
8855
#define SQLITE_STATUS_SCRATCH_USED         3  /* NOT USED */
8856
#define SQLITE_STATUS_SCRATCH_OVERFLOW     4  /* NOT USED */
8857
#define SQLITE_STATUS_MALLOC_SIZE          5
8858
#define SQLITE_STATUS_PARSER_STACK         6
8859
#define SQLITE_STATUS_PAGECACHE_SIZE       7
8860
#define SQLITE_STATUS_SCRATCH_SIZE         8  /* NOT USED */
8861
#define SQLITE_STATUS_MALLOC_COUNT         9
8862
8863
/*
8864
** CAPI3REF: Database Connection Status
8865
** METHOD: sqlite3
8866
**
8867
** ^This interface is used to retrieve runtime status information
8868
** about a single [database connection].  ^The first argument is the
8869
** database connection object to be interrogated.  ^The second argument
8870
** is an integer constant, taken from the set of
8871
** [SQLITE_DBSTATUS options], that
8872
** determines the parameter to interrogate.  The set of
8873
** [SQLITE_DBSTATUS options] is likely
8874
** to grow in future releases of SQLite.
8875
**
8876
** ^The current value of the requested parameter is written into *pCur
8877
** and the highest instantaneous value is written into *pHiwtr.  ^If
8878
** the resetFlg is true, then the highest instantaneous value is
8879
** reset back down to the current value.
8880
**
8881
** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
8882
** non-zero [error code] on failure.
8883
**
8884
** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
8885
*/
8886
SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
8887
8888
/*
8889
** CAPI3REF: Status Parameters for database connections
8890
** KEYWORDS: {SQLITE_DBSTATUS options}
8891
**
8892
** These constants are the available integer "verbs" that can be passed as
8893
** the second argument to the [sqlite3_db_status()] interface.
8894
**
8895
** New verbs may be added in future releases of SQLite. Existing verbs
8896
** might be discontinued. Applications should check the return code from
8897
** [sqlite3_db_status()] to make sure that the call worked.
8898
** The [sqlite3_db_status()] interface will return a non-zero error code
8899
** if a discontinued or unsupported verb is invoked.
8900
**
8901
** <dl>
8902
** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
8903
** <dd>This parameter returns the number of lookaside memory slots currently
8904
** checked out.</dd>)^
8905
**
8906
** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
8907
** <dd>This parameter returns the number of malloc attempts that were
8908
** satisfied using lookaside memory. Only the high-water value is meaningful;
8909
** the current value is always zero.</dd>)^
8910
**
8911
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
8912
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
8913
** <dd>This parameter returns the number of malloc attempts that might have
8914
** been satisfied using lookaside memory but failed due to the amount of
8915
** memory requested being larger than the lookaside slot size.
8916
** Only the high-water value is meaningful;
8917
** the current value is always zero.</dd>)^
8918
**
8919
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
8920
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
8921
** <dd>This parameter returns the number of malloc attempts that might have
8922
** been satisfied using lookaside memory but failed due to all lookaside
8923
** memory already being in use.
8924
** Only the high-water value is meaningful;
8925
** the current value is always zero.</dd>)^
8926
**
8927
** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
8928
** <dd>This parameter returns the approximate number of bytes of heap
8929
** memory used by all pager caches associated with the database connection.)^
8930
** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
8931
** </dd>
8932
**
8933
** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
8934
** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
8935
** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
8936
** pager cache is shared between two or more connections the bytes of heap
8937
** memory used by that pager cache is divided evenly between the attached
8938
** connections.)^  In other words, if none of the pager caches associated
8939
** with the database connection are shared, this request returns the same
8940
** value as DBSTATUS_CACHE_USED. Or, if one or more of the pager caches are
8941
** shared, the value returned by this call will be smaller than that returned
8942
** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
8943
** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.</dd>
8944
**
8945
** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
8946
** <dd>This parameter returns the approximate number of bytes of heap
8947
** memory used to store the schema for all databases associated
8948
** with the connection - main, temp, and any [ATTACH]-ed databases.)^
8949
** ^The full amount of memory used by the schemas is reported, even if the
8950
** schema memory is shared with other database connections due to
8951
** [shared cache mode] being enabled.
8952
** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
8953
** </dd>
8954
**
8955
** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
8956
** <dd>This parameter returns the approximate number of bytes of heap
8957
** and lookaside memory used by all prepared statements associated with
8958
** the database connection.)^
8959
** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
8960
** </dd>
8961
**
8962
** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
8963
** <dd>This parameter returns the number of pager cache hits that have
8964
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
8965
** is always 0.
8966
** </dd>
8967
**
8968
** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
8969
** <dd>This parameter returns the number of pager cache misses that have
8970
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
8971
** is always 0.
8972
** </dd>
8973
**
8974
** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
8975
** <dd>This parameter returns the number of dirty cache entries that have
8976
** been written to disk. Specifically, the number of pages written to the
8977
** wal file in wal mode databases, or the number of pages written to the
8978
** database file in rollback mode databases. Any pages written as part of
8979
** transaction rollback or database recovery operations are not included.
8980
** If an IO or other error occurs while writing a page to disk, the effect
8981
** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
8982
** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
8983
** </dd>
8984
**
8985
** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt>
8986
** <dd>This parameter returns the number of dirty cache entries that have
8987
** been written to disk in the middle of a transaction due to the page
8988
** cache overflowing. Transactions are more efficient if they are written
8989
** to disk all at once. When pages spill mid-transaction, that introduces
8990
** additional overhead. This parameter can be used to help identify
8991
** inefficiencies that can be resolved by increasing the cache size.
8992
** </dd>
8993
**
8994
** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
8995
** <dd>This parameter returns zero for the current value if and only if
8996
** all foreign key constraints (deferred or immediate) have been
8997
** resolved.)^  ^The highwater mark is always 0.
8998
** </dd>
8999
** </dl>
9000
*/
9001
#define SQLITE_DBSTATUS_LOOKASIDE_USED       0
9002
#define SQLITE_DBSTATUS_CACHE_USED           1
9003
#define SQLITE_DBSTATUS_SCHEMA_USED          2
9004
#define SQLITE_DBSTATUS_STMT_USED            3
9005
#define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
9006
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
9007
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
9008
#define SQLITE_DBSTATUS_CACHE_HIT            7
9009
#define SQLITE_DBSTATUS_CACHE_MISS           8
9010
#define SQLITE_DBSTATUS_CACHE_WRITE          9
9011
#define SQLITE_DBSTATUS_DEFERRED_FKS        10
9012
#define SQLITE_DBSTATUS_CACHE_USED_SHARED   11
9013
#define SQLITE_DBSTATUS_CACHE_SPILL         12
9014
#define SQLITE_DBSTATUS_MAX                 12   /* Largest defined DBSTATUS */
9015
9016
9017
/*
9018
** CAPI3REF: Prepared Statement Status
9019
** METHOD: sqlite3_stmt
9020
**
9021
** ^(Each prepared statement maintains various
9022
** [SQLITE_STMTSTATUS counters] that measure the number
9023
** of times it has performed specific operations.)^  These counters can
9024
** be used to monitor the performance characteristics of the prepared
9025
** statements.  For example, if the number of table steps greatly exceeds
9026
** the number of table searches or result rows, that would tend to indicate
9027
** that the prepared statement is using a full table scan rather than
9028
** an index.
9029
**
9030
** ^(This interface is used to retrieve and reset counter values from
9031
** a [prepared statement].  The first argument is the prepared statement
9032
** object to be interrogated.  The second argument
9033
** is an integer code for a specific [SQLITE_STMTSTATUS counter]
9034
** to be interrogated.)^
9035
** ^The current value of the requested counter is returned.
9036
** ^If the resetFlg is true, then the counter is reset to zero after this
9037
** interface call returns.
9038
**
9039
** See also: [sqlite3_status()] and [sqlite3_db_status()].
9040
*/
9041
SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
9042
9043
/*
9044
** CAPI3REF: Status Parameters for prepared statements
9045
** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
9046
**
9047
** These preprocessor macros define integer codes that name counter
9048
** values associated with the [sqlite3_stmt_status()] interface.
9049
** The meanings of the various counters are as follows:
9050
**
9051
** <dl>
9052
** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
9053
** <dd>^This is the number of times that SQLite has stepped forward in
9054
** a table as part of a full table scan.  Large numbers for this counter
9055
** may indicate opportunities for performance improvement through
9056
** careful use of indices.</dd>
9057
**
9058
** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
9059
** <dd>^This is the number of sort operations that have occurred.
9060
** A non-zero value in this counter may indicate an opportunity to
9061
** improve performance through careful use of indices.</dd>
9062
**
9063
** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
9064
** <dd>^This is the number of rows inserted into transient indices that
9065
** were created automatically in order to help joins run faster.
9066
** A non-zero value in this counter may indicate an opportunity to
9067
** improve performance by adding permanent indices that do not
9068
** need to be reinitialized each time the statement is run.</dd>
9069
**
9070
** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
9071
** <dd>^This is the number of virtual machine operations executed
9072
** by the prepared statement if that number is less than or equal
9073
** to 2147483647.  The number of virtual machine operations can be
9074
** used as a proxy for the total work done by the prepared statement.
9075
** If the number of virtual machine operations exceeds 2147483647
9076
** then the value returned by this statement status code is undefined.</dd>
9077
**
9078
** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
9079
** <dd>^This is the number of times that the prepare statement has been
9080
** automatically regenerated due to schema changes or changes to
9081
** [bound parameters] that might affect the query plan.</dd>
9082
**
9083
** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
9084
** <dd>^This is the number of times that the prepared statement has
9085
** been run.  A single "run" for the purposes of this counter is one
9086
** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
9087
** The counter is incremented on the first [sqlite3_step()] call of each
9088
** cycle.</dd>
9089
**
9090
** [[SQLITE_STMTSTATUS_FILTER_MISS]]
9091
** [[SQLITE_STMTSTATUS_FILTER HIT]]
9092
** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br>
9093
** SQLITE_STMTSTATUS_FILTER_MISS</dt>
9094
** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join
9095
** step was bypassed because a Bloom filter returned not-found.  The
9096
** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of
9097
** times that the Bloom filter returned a find, and thus the join step
9098
** had to be processed as normal.</dd>
9099
**
9100
** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
9101
** <dd>^This is the approximate number of bytes of heap memory
9102
** used to store the prepared statement.  ^This value is not actually
9103
** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
9104
** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
9105
** </dd>
9106
** </dl>
9107
*/
9108
#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
9109
#define SQLITE_STMTSTATUS_SORT              2
9110
#define SQLITE_STMTSTATUS_AUTOINDEX         3
9111
#define SQLITE_STMTSTATUS_VM_STEP           4
9112
#define SQLITE_STMTSTATUS_REPREPARE         5
9113
#define SQLITE_STMTSTATUS_RUN               6
9114
#define SQLITE_STMTSTATUS_FILTER_MISS       7
9115
#define SQLITE_STMTSTATUS_FILTER_HIT        8
9116
#define SQLITE_STMTSTATUS_MEMUSED           99
9117
9118
/*
9119
** CAPI3REF: Custom Page Cache Object
9120
**
9121
** The sqlite3_pcache type is opaque.  It is implemented by
9122
** the pluggable module.  The SQLite core has no knowledge of
9123
** its size or internal structure and never deals with the
9124
** sqlite3_pcache object except by holding and passing pointers
9125
** to the object.
9126
**
9127
** See [sqlite3_pcache_methods2] for additional information.
9128
*/
9129
typedef struct sqlite3_pcache sqlite3_pcache;
9130
9131
/*
9132
** CAPI3REF: Custom Page Cache Object
9133
**
9134
** The sqlite3_pcache_page object represents a single page in the
9135
** page cache.  The page cache will allocate instances of this
9136
** object.  Various methods of the page cache use pointers to instances
9137
** of this object as parameters or as their return value.
9138
**
9139
** See [sqlite3_pcache_methods2] for additional information.
9140
*/
9141
typedef struct sqlite3_pcache_page sqlite3_pcache_page;
9142
struct sqlite3_pcache_page {
9143
  void *pBuf;        /* The content of the page */
9144
  void *pExtra;      /* Extra information associated with the page */
9145
};
9146
9147
/*
9148
** CAPI3REF: Application Defined Page Cache.
9149
** KEYWORDS: {page cache}
9150
**
9151
** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
9152
** register an alternative page cache implementation by passing in an
9153
** instance of the sqlite3_pcache_methods2 structure.)^
9154
** In many applications, most of the heap memory allocated by
9155
** SQLite is used for the page cache.
9156
** By implementing a
9157
** custom page cache using this API, an application can better control
9158
** the amount of memory consumed by SQLite, the way in which
9159
** that memory is allocated and released, and the policies used to
9160
** determine exactly which parts of a database file are cached and for
9161
** how long.
9162
**
9163
** The alternative page cache mechanism is an
9164
** extreme measure that is only needed by the most demanding applications.
9165
** The built-in page cache is recommended for most uses.
9166
**
9167
** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
9168
** internal buffer by SQLite within the call to [sqlite3_config].  Hence
9169
** the application may discard the parameter after the call to
9170
** [sqlite3_config()] returns.)^
9171
**
9172
** [[the xInit() page cache method]]
9173
** ^(The xInit() method is called once for each effective
9174
** call to [sqlite3_initialize()])^
9175
** (usually only once during the lifetime of the process). ^(The xInit()
9176
** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
9177
** The intent of the xInit() method is to set up global data structures
9178
** required by the custom page cache implementation.
9179
** ^(If the xInit() method is NULL, then the
9180
** built-in default page cache is used instead of the application defined
9181
** page cache.)^
9182
**
9183
** [[the xShutdown() page cache method]]
9184
** ^The xShutdown() method is called by [sqlite3_shutdown()].
9185
** It can be used to clean up
9186
** any outstanding resources before process shutdown, if required.
9187
** ^The xShutdown() method may be NULL.
9188
**
9189
** ^SQLite automatically serializes calls to the xInit method,
9190
** so the xInit method need not be threadsafe.  ^The
9191
** xShutdown method is only called from [sqlite3_shutdown()] so it does
9192
** not need to be threadsafe either.  All other methods must be threadsafe
9193
** in multithreaded applications.
9194
**
9195
** ^SQLite will never invoke xInit() more than once without an intervening
9196
** call to xShutdown().
9197
**
9198
** [[the xCreate() page cache methods]]
9199
** ^SQLite invokes the xCreate() method to construct a new cache instance.
9200
** SQLite will typically create one cache instance for each open database file,
9201
** though this is not guaranteed. ^The
9202
** first parameter, szPage, is the size in bytes of the pages that must
9203
** be allocated by the cache.  ^szPage will always be a power of two.  ^The
9204
** second parameter szExtra is a number of bytes of extra storage
9205
** associated with each page cache entry.  ^The szExtra parameter will be
9206
** a number less than 250.  SQLite will use the
9207
** extra szExtra bytes on each page to store metadata about the underlying
9208
** database page on disk.  The value passed into szExtra depends
9209
** on the SQLite version, the target platform, and how SQLite was compiled.
9210
** ^The third argument to xCreate(), bPurgeable, is true if the cache being
9211
** created will be used to cache database pages of a file stored on disk, or
9212
** false if it is used for an in-memory database. The cache implementation
9213
** does not have to do anything special based upon the value of bPurgeable;
9214
** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
9215
** never invoke xUnpin() except to deliberately delete a page.
9216
** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
9217
** false will always have the "discard" flag set to true.
9218
** ^Hence, a cache created with bPurgeable set to false will
9219
** never contain any unpinned pages.
9220
**
9221
** [[the xCachesize() page cache method]]
9222
** ^(The xCachesize() method may be called at any time by SQLite to set the
9223
** suggested maximum cache-size (number of pages stored) for the cache
9224
** instance passed as the first argument. This is the value configured using
9225
** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
9226
** parameter, the implementation is not required to do anything with this
9227
** value; it is advisory only.
9228
**
9229
** [[the xPagecount() page cache methods]]
9230
** The xPagecount() method must return the number of pages currently
9231
** stored in the cache, both pinned and unpinned.
9232
**
9233
** [[the xFetch() page cache methods]]
9234
** The xFetch() method locates a page in the cache and returns a pointer to
9235
** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
9236
** The pBuf element of the returned sqlite3_pcache_page object will be a
9237
** pointer to a buffer of szPage bytes used to store the content of a
9238
** single database page.  The pExtra element of sqlite3_pcache_page will be
9239
** a pointer to the szExtra bytes of extra storage that SQLite has requested
9240
** for each entry in the page cache.
9241
**
9242
** The page to be fetched is determined by the key. ^The minimum key value
9243
** is 1.  After it has been retrieved using xFetch, the page is considered
9244
** to be "pinned".
9245
**
9246
** If the requested page is already in the page cache, then the page cache
9247
** implementation must return a pointer to the page buffer with its content
9248
** intact.  If the requested page is not already in the cache, then the
9249
** cache implementation should use the value of the createFlag
9250
** parameter to help it determine what action to take:
9251
**
9252
** <table border=1 width=85% align=center>
9253
** <tr><th> createFlag <th> Behavior when page is not already in cache
9254
** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
9255
** <tr><td> 1 <td> Allocate a new page if it is easy and convenient to do so.
9256
**                 Otherwise return NULL.
9257
** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
9258
**                 NULL if allocating a new page is effectively impossible.
9259
** </table>
9260
**
9261
** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
9262
** will only use a createFlag of 2 after a prior call with a createFlag of 1
9263
** failed.)^  In between the xFetch() calls, SQLite may
9264
** attempt to unpin one or more cache pages by spilling the content of
9265
** pinned pages to disk and synching the operating system disk cache.
9266
**
9267
** [[the xUnpin() page cache method]]
9268
** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
9269
** as its second argument.  If the third parameter, discard, is non-zero,
9270
** then the page must be evicted from the cache.
9271
** ^If the discard parameter is
9272
** zero, then the page may be discarded or retained at the discretion of the
9273
** page cache implementation. ^The page cache implementation
9274
** may choose to evict unpinned pages at any time.
9275
**
9276
** The cache must not perform any reference counting. A single
9277
** call to xUnpin() unpins the page regardless of the number of prior calls
9278
** to xFetch().
9279
**
9280
** [[the xRekey() page cache methods]]
9281
** The xRekey() method is used to change the key value associated with the
9282
** page passed as the second argument. If the cache
9283
** previously contains an entry associated with newKey, it must be
9284
** discarded. ^Any prior cache entry associated with newKey is guaranteed not
9285
** to be pinned.
9286
**
9287
** When SQLite calls the xTruncate() method, the cache must discard all
9288
** existing cache entries with page numbers (keys) greater than or equal
9289
** to the value of the iLimit parameter passed to xTruncate(). If any
9290
** of these pages are pinned, they become implicitly unpinned, meaning that
9291
** they can be safely discarded.
9292
**
9293
** [[the xDestroy() page cache method]]
9294
** ^The xDestroy() method is used to delete a cache allocated by xCreate().
9295
** All resources associated with the specified cache should be freed. ^After
9296
** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
9297
** handle invalid, and will not use it with any other sqlite3_pcache_methods2
9298
** functions.
9299
**
9300
** [[the xShrink() page cache method]]
9301
** ^SQLite invokes the xShrink() method when it wants the page cache to
9302
** free up as much of heap memory as possible.  The page cache implementation
9303
** is not obligated to free any memory, but well-behaved implementations should
9304
** do their best.
9305
*/
9306
typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
9307
struct sqlite3_pcache_methods2 {
9308
  int iVersion;
9309
  void *pArg;
9310
  int (*xInit)(void*);
9311
  void (*xShutdown)(void*);
9312
  sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
9313
  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
9314
  int (*xPagecount)(sqlite3_pcache*);
9315
  sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
9316
  void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
9317
  void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
9318
      unsigned oldKey, unsigned newKey);
9319
  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
9320
  void (*xDestroy)(sqlite3_pcache*);
9321
  void (*xShrink)(sqlite3_pcache*);
9322
};
9323
9324
/*
9325
** This is the obsolete pcache_methods object that has now been replaced
9326
** by sqlite3_pcache_methods2.  This object is not used by SQLite.  It is
9327
** retained in the header file for backwards compatibility only.
9328
*/
9329
typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
9330
struct sqlite3_pcache_methods {
9331
  void *pArg;
9332
  int (*xInit)(void*);
9333
  void (*xShutdown)(void*);
9334
  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
9335
  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
9336
  int (*xPagecount)(sqlite3_pcache*);
9337
  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
9338
  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
9339
  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
9340
  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
9341
  void (*xDestroy)(sqlite3_pcache*);
9342
};
9343
9344
9345
/*
9346
** CAPI3REF: Online Backup Object
9347
**
9348
** The sqlite3_backup object records state information about an ongoing
9349
** online backup operation.  ^The sqlite3_backup object is created by
9350
** a call to [sqlite3_backup_init()] and is destroyed by a call to
9351
** [sqlite3_backup_finish()].
9352
**
9353
** See Also: [Using the SQLite Online Backup API]
9354
*/
9355
typedef struct sqlite3_backup sqlite3_backup;
9356
9357
/*
9358
** CAPI3REF: Online Backup API.
9359
**
9360
** The backup API copies the content of one database into another.
9361
** It is useful either for creating backups of databases or
9362
** for copying in-memory databases to or from persistent files.
9363
**
9364
** See Also: [Using the SQLite Online Backup API]
9365
**
9366
** ^SQLite holds a write transaction open on the destination database file
9367
** for the duration of the backup operation.
9368
** ^The source database is read-locked only while it is being read;
9369
** it is not locked continuously for the entire backup operation.
9370
** ^Thus, the backup may be performed on a live source database without
9371
** preventing other database connections from
9372
** reading or writing to the source database while the backup is underway.
9373
**
9374
** ^(To perform a backup operation:
9375
**   <ol>
9376
**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
9377
**         backup,
9378
**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
9379
**         the data between the two databases, and finally
9380
**     <li><b>sqlite3_backup_finish()</b> is called to release all resources
9381
**         associated with the backup operation.
9382
**   </ol>)^
9383
** There should be exactly one call to sqlite3_backup_finish() for each
9384
** successful call to sqlite3_backup_init().
9385
**
9386
** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
9387
**
9388
** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
9389
** [database connection] associated with the destination database
9390
** and the database name, respectively.
9391
** ^The database name is "main" for the main database, "temp" for the
9392
** temporary database, or the name specified after the AS keyword in
9393
** an [ATTACH] statement for an attached database.
9394
** ^The S and M arguments passed to
9395
** sqlite3_backup_init(D,N,S,M) identify the [database connection]
9396
** and database name of the source database, respectively.
9397
** ^The source and destination [database connections] (parameters S and D)
9398
** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
9399
** an error.
9400
**
9401
** ^A call to sqlite3_backup_init() will fail, returning NULL, if
9402
** there is already a read or read-write transaction open on the
9403
** destination database.
9404
**
9405
** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
9406
** returned and an error code and error message are stored in the
9407
** destination [database connection] D.
9408
** ^The error code and message for the failed call to sqlite3_backup_init()
9409
** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
9410
** [sqlite3_errmsg16()] functions.
9411
** ^A successful call to sqlite3_backup_init() returns a pointer to an
9412
** [sqlite3_backup] object.
9413
** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
9414
** sqlite3_backup_finish() functions to perform the specified backup
9415
** operation.
9416
**
9417
** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
9418
**
9419
** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
9420
** the source and destination databases specified by [sqlite3_backup] object B.
9421
** ^If N is negative, all remaining source pages are copied.
9422
** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
9423
** are still more pages to be copied, then the function returns [SQLITE_OK].
9424
** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
9425
** from source to destination, then it returns [SQLITE_DONE].
9426
** ^If an error occurs while running sqlite3_backup_step(B,N),
9427
** then an [error code] is returned. ^As well as [SQLITE_OK] and
9428
** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
9429
** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
9430
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
9431
**
9432
** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
9433
** <ol>
9434
** <li> the destination database was opened read-only, or
9435
** <li> the destination database is using write-ahead-log journaling
9436
** and the destination and source page sizes differ, or
9437
** <li> the destination database is an in-memory database and the
9438
** destination and source page sizes differ.
9439
** </ol>)^
9440
**
9441
** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
9442
** the [sqlite3_busy_handler | busy-handler function]
9443
** is invoked (if one is specified). ^If the
9444
** busy-handler returns non-zero before the lock is available, then
9445
** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
9446
** sqlite3_backup_step() can be retried later. ^If the source
9447
** [database connection]
9448
** is being used to write to the source database when sqlite3_backup_step()
9449
** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
9450
** case the call to sqlite3_backup_step() can be retried later on. ^(If
9451
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
9452
** [SQLITE_READONLY] is returned, then
9453
** there is no point in retrying the call to sqlite3_backup_step(). These
9454
** errors are considered fatal.)^  The application must accept
9455
** that the backup operation has failed and pass the backup operation handle
9456
** to the sqlite3_backup_finish() to release associated resources.
9457
**
9458
** ^The first call to sqlite3_backup_step() obtains an exclusive lock
9459
** on the destination file. ^The exclusive lock is not released until either
9460
** sqlite3_backup_finish() is called or the backup operation is complete
9461
** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
9462
** sqlite3_backup_step() obtains a [shared lock] on the source database that
9463
** lasts for the duration of the sqlite3_backup_step() call.
9464
** ^Because the source database is not locked between calls to
9465
** sqlite3_backup_step(), the source database may be modified mid-way
9466
** through the backup process.  ^If the source database is modified by an
9467
** external process or via a database connection other than the one being
9468
** used by the backup operation, then the backup will be automatically
9469
** restarted by the next call to sqlite3_backup_step(). ^If the source
9470
** database is modified by using the same database connection as is used
9471
** by the backup operation, then the backup database is automatically
9472
** updated at the same time.
9473
**
9474
** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
9475
**
9476
** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
9477
** application wishes to abandon the backup operation, the application
9478
** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
9479
** ^The sqlite3_backup_finish() interfaces releases all
9480
** resources associated with the [sqlite3_backup] object.
9481
** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
9482
** active write-transaction on the destination database is rolled back.
9483
** The [sqlite3_backup] object is invalid
9484
** and may not be used following a call to sqlite3_backup_finish().
9485
**
9486
** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
9487
** sqlite3_backup_step() errors occurred, regardless of whether or not
9488
** sqlite3_backup_step() completed.
9489
** ^If an out-of-memory condition or IO error occurred during any prior
9490
** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
9491
** sqlite3_backup_finish() returns the corresponding [error code].
9492
**
9493
** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
9494
** is not a permanent error and does not affect the return value of
9495
** sqlite3_backup_finish().
9496
**
9497
** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
9498
** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
9499
**
9500
** ^The sqlite3_backup_remaining() routine returns the number of pages still
9501
** to be backed up at the conclusion of the most recent sqlite3_backup_step().
9502
** ^The sqlite3_backup_pagecount() routine returns the total number of pages
9503
** in the source database at the conclusion of the most recent
9504
** sqlite3_backup_step().
9505
** ^(The values returned by these functions are only updated by
9506
** sqlite3_backup_step(). If the source database is modified in a way that
9507
** changes the size of the source database or the number of pages remaining,
9508
** those changes are not reflected in the output of sqlite3_backup_pagecount()
9509
** and sqlite3_backup_remaining() until after the next
9510
** sqlite3_backup_step().)^
9511
**
9512
** <b>Concurrent Usage of Database Handles</b>
9513
**
9514
** ^The source [database connection] may be used by the application for other
9515
** purposes while a backup operation is underway or being initialized.
9516
** ^If SQLite is compiled and configured to support threadsafe database
9517
** connections, then the source database connection may be used concurrently
9518
** from within other threads.
9519
**
9520
** However, the application must guarantee that the destination
9521
** [database connection] is not passed to any other API (by any thread) after
9522
** sqlite3_backup_init() is called and before the corresponding call to
9523
** sqlite3_backup_finish().  SQLite does not currently check to see
9524
** if the application incorrectly accesses the destination [database connection]
9525
** and so no error code is reported, but the operations may malfunction
9526
** nevertheless.  Use of the destination database connection while a
9527
** backup is in progress might also cause a mutex deadlock.
9528
**
9529
** If running in [shared cache mode], the application must
9530
** guarantee that the shared cache used by the destination database
9531
** is not accessed while the backup is running. In practice this means
9532
** that the application must guarantee that the disk file being
9533
** backed up to is not accessed by any connection within the process,
9534
** not just the specific connection that was passed to sqlite3_backup_init().
9535
**
9536
** The [sqlite3_backup] object itself is partially threadsafe. Multiple
9537
** threads may safely make multiple concurrent calls to sqlite3_backup_step().
9538
** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
9539
** APIs are not strictly speaking threadsafe. If they are invoked at the
9540
** same time as another thread is invoking sqlite3_backup_step() it is
9541
** possible that they return invalid values.
9542
**
9543
** <b>Alternatives To Using The Backup API</b>
9544
**
9545
** Other techniques for safely creating a consistent backup of an SQLite
9546
** database include:
9547
**
9548
** <ul>
9549
** <li> The [VACUUM INTO] command.
9550
** <li> The [sqlite3_rsync] utility program.
9551
** </ul>
9552
*/
9553
SQLITE_API sqlite3_backup *sqlite3_backup_init(
9554
  sqlite3 *pDest,                        /* Destination database handle */
9555
  const char *zDestName,                 /* Destination database name */
9556
  sqlite3 *pSource,                      /* Source database handle */
9557
  const char *zSourceName                /* Source database name */
9558
);
9559
SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
9560
SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
9561
SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
9562
SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
9563
9564
/*
9565
** CAPI3REF: Unlock Notification
9566
** METHOD: sqlite3
9567
**
9568
** ^When running in shared-cache mode, a database operation may fail with
9569
** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
9570
** individual tables within the shared-cache cannot be obtained. See
9571
** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
9572
** ^This API may be used to register a callback that SQLite will invoke
9573
** when the connection currently holding the required lock relinquishes it.
9574
** ^This API is only available if the library was compiled with the
9575
** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
9576
**
9577
** See Also: [Using the SQLite Unlock Notification Feature].
9578
**
9579
** ^Shared-cache locks are released when a database connection concludes
9580
** its current transaction, either by committing it or rolling it back.
9581
**
9582
** ^When a connection (known as the blocked connection) fails to obtain a
9583
** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
9584
** identity of the database connection (the blocking connection) that
9585
** has locked the required resource is stored internally. ^After an
9586
** application receives an SQLITE_LOCKED error, it may call the
9587
** sqlite3_unlock_notify() method with the blocked connection handle as
9588
** the first argument to register for a callback that will be invoked
9589
** when the blocking connection's current transaction is concluded. ^The
9590
** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
9591
** call that concludes the blocking connection's transaction.
9592
**
9593
** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
9594
** there is a chance that the blocking connection will have already
9595
** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
9596
** If this happens, then the specified callback is invoked immediately,
9597
** from within the call to sqlite3_unlock_notify().)^
9598
**
9599
** ^If the blocked connection is attempting to obtain a write-lock on a
9600
** shared-cache table, and more than one other connection currently holds
9601
** a read-lock on the same table, then SQLite arbitrarily selects one of
9602
** the other connections to use as the blocking connection.
9603
**
9604
** ^(There may be at most one unlock-notify callback registered by a
9605
** blocked connection. If sqlite3_unlock_notify() is called when the
9606
** blocked connection already has a registered unlock-notify callback,
9607
** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
9608
** called with a NULL pointer as its second argument, then any existing
9609
** unlock-notify callback is canceled. ^The blocked connection's
9610
** unlock-notify callback may also be canceled by closing the blocked
9611
** connection using [sqlite3_close()].
9612
**
9613
** The unlock-notify callback is not reentrant. If an application invokes
9614
** any sqlite3_xxx API functions from within an unlock-notify callback, a
9615
** crash or deadlock may be the result.
9616
**
9617
** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
9618
** returns SQLITE_OK.
9619
**
9620
** <b>Callback Invocation Details</b>
9621
**
9622
** When an unlock-notify callback is registered, the application provides a
9623
** single void* pointer that is passed to the callback when it is invoked.
9624
** However, the signature of the callback function allows SQLite to pass
9625
** it an array of void* context pointers. The first argument passed to
9626
** an unlock-notify callback is a pointer to an array of void* pointers,
9627
** and the second is the number of entries in the array.
9628
**
9629
** When a blocking connection's transaction is concluded, there may be
9630
** more than one blocked connection that has registered for an unlock-notify
9631
** callback. ^If two or more such blocked connections have specified the
9632
** same callback function, then instead of invoking the callback function
9633
** multiple times, it is invoked once with the set of void* context pointers
9634
** specified by the blocked connections bundled together into an array.
9635
** This gives the application an opportunity to prioritize any actions
9636
** related to the set of unblocked database connections.
9637
**
9638
** <b>Deadlock Detection</b>
9639
**
9640
** Assuming that after registering for an unlock-notify callback a
9641
** database waits for the callback to be issued before taking any further
9642
** action (a reasonable assumption), then using this API may cause the
9643
** application to deadlock. For example, if connection X is waiting for
9644
** connection Y's transaction to be concluded, and similarly connection
9645
** Y is waiting on connection X's transaction, then neither connection
9646
** will proceed and the system may remain deadlocked indefinitely.
9647
**
9648
** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
9649
** detection. ^If a given call to sqlite3_unlock_notify() would put the
9650
** system in a deadlocked state, then SQLITE_LOCKED is returned and no
9651
** unlock-notify callback is registered. The system is said to be in
9652
** a deadlocked state if connection A has registered for an unlock-notify
9653
** callback on the conclusion of connection B's transaction, and connection
9654
** B has itself registered for an unlock-notify callback when connection
9655
** A's transaction is concluded. ^Indirect deadlock is also detected, so
9656
** the system is also considered to be deadlocked if connection B has
9657
** registered for an unlock-notify callback on the conclusion of connection
9658
** C's transaction, where connection C is waiting on connection A. ^Any
9659
** number of levels of indirection are allowed.
9660
**
9661
** <b>The "DROP TABLE" Exception</b>
9662
**
9663
** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
9664
** always appropriate to call sqlite3_unlock_notify(). There is however,
9665
** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
9666
** SQLite checks if there are any currently executing SELECT statements
9667
** that belong to the same connection. If there are, SQLITE_LOCKED is
9668
** returned. In this case there is no "blocking connection", so invoking
9669
** sqlite3_unlock_notify() results in the unlock-notify callback being
9670
** invoked immediately. If the application then re-attempts the "DROP TABLE"
9671
** or "DROP INDEX" query, an infinite loop might be the result.
9672
**
9673
** One way around this problem is to check the extended error code returned
9674
** by an sqlite3_step() call. ^(If there is a blocking connection, then the
9675
** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
9676
** the special "DROP TABLE/INDEX" case, the extended error code is just
9677
** SQLITE_LOCKED.)^
9678
*/
9679
SQLITE_API int sqlite3_unlock_notify(
9680
  sqlite3 *pBlocked,                          /* Waiting connection */
9681
  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
9682
  void *pNotifyArg                            /* Argument to pass to xNotify */
9683
);
9684
9685
9686
/*
9687
** CAPI3REF: String Comparison
9688
**
9689
** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
9690
** and extensions to compare the contents of two buffers containing UTF-8
9691
** strings in a case-independent fashion, using the same definition of "case
9692
** independence" that SQLite uses internally when comparing identifiers.
9693
*/
9694
SQLITE_API int sqlite3_stricmp(const char *, const char *);
9695
SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
9696
9697
/*
9698
** CAPI3REF: String Globbing
9699
*
9700
** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
9701
** string X matches the [GLOB] pattern P.
9702
** ^The definition of [GLOB] pattern matching used in
9703
** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
9704
** SQL dialect understood by SQLite.  ^The [sqlite3_strglob(P,X)] function
9705
** is case sensitive.
9706
**
9707
** Note that this routine returns zero on a match and non-zero if the strings
9708
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9709
**
9710
** See also: [sqlite3_strlike()].
9711
*/
9712
SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
9713
9714
/*
9715
** CAPI3REF: String LIKE Matching
9716
*
9717
** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
9718
** string X matches the [LIKE] pattern P with escape character E.
9719
** ^The definition of [LIKE] pattern matching used in
9720
** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
9721
** operator in the SQL dialect understood by SQLite.  ^For "X LIKE P" without
9722
** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
9723
** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
9724
** insensitive - equivalent upper and lower case ASCII characters match
9725
** one another.
9726
**
9727
** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
9728
** only ASCII characters are case folded.
9729
**
9730
** Note that this routine returns zero on a match and non-zero if the strings
9731
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9732
**
9733
** See also: [sqlite3_strglob()].
9734
*/
9735
SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
9736
9737
/*
9738
** CAPI3REF: Error Logging Interface
9739
**
9740
** ^The [sqlite3_log()] interface writes a message into the [error log]
9741
** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
9742
** ^If logging is enabled, the zFormat string and subsequent arguments are
9743
** used with [sqlite3_snprintf()] to generate the final output string.
9744
**
9745
** The sqlite3_log() interface is intended for use by extensions such as
9746
** virtual tables, collating functions, and SQL functions.  While there is
9747
** nothing to prevent an application from calling sqlite3_log(), doing so
9748
** is considered bad form.
9749
**
9750
** The zFormat string must not be NULL.
9751
**
9752
** To avoid deadlocks and other threading problems, the sqlite3_log() routine
9753
** will not use dynamically allocated memory.  The log message is stored in
9754
** a fixed-length buffer on the stack.  If the log message is longer than
9755
** a few hundred characters, it will be truncated to the length of the
9756
** buffer.
9757
*/
9758
SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
9759
9760
/*
9761
** CAPI3REF: Write-Ahead Log Commit Hook
9762
** METHOD: sqlite3
9763
**
9764
** ^The [sqlite3_wal_hook()] function is used to register a callback that
9765
** is invoked each time data is committed to a database in wal mode.
9766
**
9767
** ^(The callback is invoked by SQLite after the commit has taken place and
9768
** the associated write-lock on the database released)^, so the implementation
9769
** may read, write or [checkpoint] the database as required.
9770
**
9771
** ^The first parameter passed to the callback function when it is invoked
9772
** is a copy of the third parameter passed to sqlite3_wal_hook() when
9773
** registering the callback. ^The second is a copy of the database handle.
9774
** ^The third parameter is the name of the database that was written to -
9775
** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
9776
** is the number of pages currently in the write-ahead log file,
9777
** including those that were just committed.
9778
**
9779
** The callback function should normally return [SQLITE_OK].  ^If an error
9780
** code is returned, that error will propagate back up through the
9781
** SQLite code base to cause the statement that provoked the callback
9782
** to report an error, though the commit will have still occurred. If the
9783
** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
9784
** that does not correspond to any valid SQLite error code, the results
9785
** are undefined.
9786
**
9787
** A single database handle may have at most a single write-ahead log callback
9788
** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
9789
** previously registered write-ahead log callback. ^The return value is
9790
** a copy of the third parameter from the previous call, if any, or 0.
9791
** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the
9792
** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
9793
** overwrite any prior [sqlite3_wal_hook()] settings.
9794
*/
9795
SQLITE_API void *sqlite3_wal_hook(
9796
  sqlite3*,
9797
  int(*)(void *,sqlite3*,const char*,int),
9798
  void*
9799
);
9800
9801
/*
9802
** CAPI3REF: Configure an auto-checkpoint
9803
** METHOD: sqlite3
9804
**
9805
** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
9806
** [sqlite3_wal_hook()] that causes any database on [database connection] D
9807
** to automatically [checkpoint]
9808
** after committing a transaction if there are N or
9809
** more frames in the [write-ahead log] file.  ^Passing zero or
9810
** a negative value as the nFrame parameter disables automatic
9811
** checkpoints entirely.
9812
**
9813
** ^The callback registered by this function replaces any existing callback
9814
** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
9815
** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
9816
** configured by this function.
9817
**
9818
** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
9819
** from SQL.
9820
**
9821
** ^Checkpoints initiated by this mechanism are
9822
** [sqlite3_wal_checkpoint_v2|PASSIVE].
9823
**
9824
** ^Every new [database connection] defaults to having the auto-checkpoint
9825
** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
9826
** pages.  The use of this interface
9827
** is only necessary if the default setting is found to be suboptimal
9828
** for a particular application.
9829
*/
9830
SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
9831
9832
/*
9833
** CAPI3REF: Checkpoint a database
9834
** METHOD: sqlite3
9835
**
9836
** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
9837
** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
9838
**
9839
** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
9840
** [write-ahead log] for database X on [database connection] D to be
9841
** transferred into the database file and for the write-ahead log to
9842
** be reset.  See the [checkpointing] documentation for addition
9843
** information.
9844
**
9845
** This interface used to be the only way to cause a checkpoint to
9846
** occur.  But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
9847
** interface was added.  This interface is retained for backwards
9848
** compatibility and as a convenience for applications that need to manually
9849
** start a callback but which do not need the full power (and corresponding
9850
** complication) of [sqlite3_wal_checkpoint_v2()].
9851
*/
9852
SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
9853
9854
/*
9855
** CAPI3REF: Checkpoint a database
9856
** METHOD: sqlite3
9857
**
9858
** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
9859
** operation on database X of [database connection] D in mode M.  Status
9860
** information is written back into integers pointed to by L and C.)^
9861
** ^(The M parameter must be a valid [checkpoint mode]:)^
9862
**
9863
** <dl>
9864
** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
9865
**   ^Checkpoint as many frames as possible without waiting for any database
9866
**   readers or writers to finish, then sync the database file if all frames
9867
**   in the log were checkpointed. ^The [busy-handler callback]
9868
**   is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
9869
**   ^On the other hand, passive mode might leave the checkpoint unfinished
9870
**   if there are concurrent readers or writers.
9871
**
9872
** <dt>SQLITE_CHECKPOINT_FULL<dd>
9873
**   ^This mode blocks (it invokes the
9874
**   [sqlite3_busy_handler|busy-handler callback]) until there is no
9875
**   database writer and all readers are reading from the most recent database
9876
**   snapshot. ^It then checkpoints all frames in the log file and syncs the
9877
**   database file. ^This mode blocks new database writers while it is pending,
9878
**   but new database readers are allowed to continue unimpeded.
9879
**
9880
** <dt>SQLITE_CHECKPOINT_RESTART<dd>
9881
**   ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
9882
**   that after checkpointing the log file it blocks (calls the
9883
**   [busy-handler callback])
9884
**   until all readers are reading from the database file only. ^This ensures
9885
**   that the next writer will restart the log file from the beginning.
9886
**   ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
9887
**   database writer attempts while it is pending, but does not impede readers.
9888
**
9889
** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
9890
**   ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
9891
**   addition that it also truncates the log file to zero bytes just prior
9892
**   to a successful return.
9893
** </dl>
9894
**
9895
** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
9896
** the log file or to -1 if the checkpoint could not run because
9897
** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
9898
** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
9899
** log file (including any that were already checkpointed before the function
9900
** was called) or to -1 if the checkpoint could not run due to an error or
9901
** because the database is not in WAL mode. ^Note that upon successful
9902
** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
9903
** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
9904
**
9905
** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
9906
** any other process is running a checkpoint operation at the same time, the
9907
** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
9908
** busy-handler configured, it will not be invoked in this case.
9909
**
9910
** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
9911
** exclusive "writer" lock on the database file. ^If the writer lock cannot be
9912
** obtained immediately, and a busy-handler is configured, it is invoked and
9913
** the writer lock retried until either the busy-handler returns 0 or the lock
9914
** is successfully obtained. ^The busy-handler is also invoked while waiting for
9915
** database readers as described above. ^If the busy-handler returns 0 before
9916
** the writer lock is obtained or while waiting for database readers, the
9917
** checkpoint operation proceeds from that point in the same way as
9918
** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
9919
** without blocking any further. ^SQLITE_BUSY is returned in this case.
9920
**
9921
** ^If parameter zDb is NULL or points to a zero length string, then the
9922
** specified operation is attempted on all WAL databases [attached] to
9923
** [database connection] db.  In this case the
9924
** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
9925
** an SQLITE_BUSY error is encountered when processing one or more of the
9926
** attached WAL databases, the operation is still attempted on any remaining
9927
** attached databases and SQLITE_BUSY is returned at the end. ^If any other
9928
** error occurs while processing an attached database, processing is abandoned
9929
** and the error code is returned to the caller immediately. ^If no error
9930
** (SQLITE_BUSY or otherwise) is encountered while processing the attached
9931
** databases, SQLITE_OK is returned.
9932
**
9933
** ^If database zDb is the name of an attached database that is not in WAL
9934
** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
9935
** zDb is not NULL (or a zero length string) and is not the name of any
9936
** attached database, SQLITE_ERROR is returned to the caller.
9937
**
9938
** ^Unless it returns SQLITE_MISUSE,
9939
** the sqlite3_wal_checkpoint_v2() interface
9940
** sets the error information that is queried by
9941
** [sqlite3_errcode()] and [sqlite3_errmsg()].
9942
**
9943
** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
9944
** from SQL.
9945
*/
9946
SQLITE_API int sqlite3_wal_checkpoint_v2(
9947
  sqlite3 *db,                    /* Database handle */
9948
  const char *zDb,                /* Name of attached database (or NULL) */
9949
  int eMode,                      /* SQLITE_CHECKPOINT_* value */
9950
  int *pnLog,                     /* OUT: Size of WAL log in frames */
9951
  int *pnCkpt                     /* OUT: Total number of frames checkpointed */
9952
);
9953
9954
/*
9955
** CAPI3REF: Checkpoint Mode Values
9956
** KEYWORDS: {checkpoint mode}
9957
**
9958
** These constants define all valid values for the "checkpoint mode" passed
9959
** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
9960
** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
9961
** meaning of each of these checkpoint modes.
9962
*/
9963
#define SQLITE_CHECKPOINT_PASSIVE  0  /* Do as much as possible w/o blocking */
9964
#define SQLITE_CHECKPOINT_FULL     1  /* Wait for writers, then checkpoint */
9965
#define SQLITE_CHECKPOINT_RESTART  2  /* Like FULL but wait for readers */
9966
#define SQLITE_CHECKPOINT_TRUNCATE 3  /* Like RESTART but also truncate WAL */
9967
9968
/*
9969
** CAPI3REF: Virtual Table Interface Configuration
9970
**
9971
** This function may be called by either the [xConnect] or [xCreate] method
9972
** of a [virtual table] implementation to configure
9973
** various facets of the virtual table interface.
9974
**
9975
** If this interface is invoked outside the context of an xConnect or
9976
** xCreate virtual table method then the behavior is undefined.
9977
**
9978
** In the call sqlite3_vtab_config(D,C,...) the D parameter is the
9979
** [database connection] in which the virtual table is being created and
9980
** which is passed in as the first argument to the [xConnect] or [xCreate]
9981
** method that is invoking sqlite3_vtab_config().  The C parameter is one
9982
** of the [virtual table configuration options].  The presence and meaning
9983
** of parameters after C depend on which [virtual table configuration option]
9984
** is used.
9985
*/
9986
SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
9987
9988
/*
9989
** CAPI3REF: Virtual Table Configuration Options
9990
** KEYWORDS: {virtual table configuration options}
9991
** KEYWORDS: {virtual table configuration option}
9992
**
9993
** These macros define the various options to the
9994
** [sqlite3_vtab_config()] interface that [virtual table] implementations
9995
** can use to customize and optimize their behavior.
9996
**
9997
** <dl>
9998
** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]]
9999
** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt>
10000
** <dd>Calls of the form
10001
** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
10002
** where X is an integer.  If X is zero, then the [virtual table] whose
10003
** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
10004
** support constraints.  In this configuration (which is the default) if
10005
** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
10006
** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
10007
** specified as part of the user's SQL statement, regardless of the actual
10008
** ON CONFLICT mode specified.
10009
**
10010
** If X is non-zero, then the virtual table implementation guarantees
10011
** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
10012
** any modifications to internal or persistent data structures have been made.
10013
** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
10014
** is able to roll back a statement or database transaction, and abandon
10015
** or continue processing the current SQL statement as appropriate.
10016
** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
10017
** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
10018
** had been ABORT.
10019
**
10020
** Virtual table implementations that are required to handle OR REPLACE
10021
** must do so within the [xUpdate] method. If a call to the
10022
** [sqlite3_vtab_on_conflict()] function indicates that the current ON
10023
** CONFLICT policy is REPLACE, the virtual table implementation should
10024
** silently replace the appropriate rows within the xUpdate callback and
10025
** return SQLITE_OK. Or, if this is not possible, it may return
10026
** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
10027
** constraint handling.
10028
** </dd>
10029
**
10030
** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt>
10031
** <dd>Calls of the form
10032
** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the
10033
** the [xConnect] or [xCreate] methods of a [virtual table] implementation
10034
** prohibits that virtual table from being used from within triggers and
10035
** views.
10036
** </dd>
10037
**
10038
** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt>
10039
** <dd>Calls of the form
10040
** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the
10041
** [xConnect] or [xCreate] methods of a [virtual table] implementation
10042
** identify that virtual table as being safe to use from within triggers
10043
** and views.  Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the
10044
** virtual table can do no serious harm even if it is controlled by a
10045
** malicious hacker.  Developers should avoid setting the SQLITE_VTAB_INNOCUOUS
10046
** flag unless absolutely necessary.
10047
** </dd>
10048
**
10049
** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]<dt>SQLITE_VTAB_USES_ALL_SCHEMAS</dt>
10050
** <dd>Calls of the form
10051
** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the
10052
** the [xConnect] or [xCreate] methods of a [virtual table] implementation
10053
** instruct the query planner to begin at least a read transaction on
10054
** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the
10055
** virtual table is used.
10056
** </dd>
10057
** </dl>
10058
*/
10059
#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
10060
#define SQLITE_VTAB_INNOCUOUS          2
10061
#define SQLITE_VTAB_DIRECTONLY         3
10062
#define SQLITE_VTAB_USES_ALL_SCHEMAS   4
10063
10064
/*
10065
** CAPI3REF: Determine The Virtual Table Conflict Policy
10066
**
10067
** This function may only be called from within a call to the [xUpdate] method
10068
** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
10069
** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
10070
** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
10071
** of the SQL statement that triggered the call to the [xUpdate] method of the
10072
** [virtual table].
10073
*/
10074
SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
10075
10076
/*
10077
** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE
10078
**
10079
** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn]
10080
** method of a [virtual table], then it might return true if the
10081
** column is being fetched as part of an UPDATE operation during which the
10082
** column value will not change.  The virtual table implementation can use
10083
** this hint as permission to substitute a return value that is less
10084
** expensive to compute and that the corresponding
10085
** [xUpdate] method understands as a "no-change" value.
10086
**
10087
** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that
10088
** the column is not changed by the UPDATE statement, then the xColumn
10089
** method can optionally return without setting a result, without calling
10090
** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces].
10091
** In that case, [sqlite3_value_nochange(X)] will return true for the
10092
** same column in the [xUpdate] method.
10093
**
10094
** The sqlite3_vtab_nochange() routine is an optimization.  Virtual table
10095
** implementations should continue to give a correct answer even if the
10096
** sqlite3_vtab_nochange() interface were to always return false.  In the
10097
** current implementation, the sqlite3_vtab_nochange() interface does always
10098
** returns false for the enhanced [UPDATE FROM] statement.
10099
*/
10100
SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*);
10101
10102
/*
10103
** CAPI3REF: Determine The Collation For a Virtual Table Constraint
10104
** METHOD: sqlite3_index_info
10105
**
10106
** This function may only be called from within a call to the [xBestIndex]
10107
** method of a [virtual table].  This function returns a pointer to a string
10108
** that is the name of the appropriate collation sequence to use for text
10109
** comparisons on the constraint identified by its arguments.
10110
**
10111
** The first argument must be the pointer to the [sqlite3_index_info] object
10112
** that is the first parameter to the xBestIndex() method. The second argument
10113
** must be an index into the aConstraint[] array belonging to the
10114
** sqlite3_index_info structure passed to xBestIndex.
10115
**
10116
** Important:
10117
** The first parameter must be the same pointer that is passed into the
10118
** xBestMethod() method.  The first parameter may not be a pointer to a
10119
** different [sqlite3_index_info] object, even an exact copy.
10120
**
10121
** The return value is computed as follows:
10122
**
10123
** <ol>
10124
** <li><p> If the constraint comes from a WHERE clause expression that contains
10125
**         a [COLLATE operator], then the name of the collation specified by
10126
**         that COLLATE operator is returned.
10127
** <li><p> If there is no COLLATE operator, but the column that is the subject
10128
**         of the constraint specifies an alternative collating sequence via
10129
**         a [COLLATE clause] on the column definition within the CREATE TABLE
10130
**         statement that was passed into [sqlite3_declare_vtab()], then the
10131
**         name of that alternative collating sequence is returned.
10132
** <li><p> Otherwise, "BINARY" is returned.
10133
** </ol>
10134
*/
10135
SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int);
10136
10137
/*
10138
** CAPI3REF: Determine if a virtual table query is DISTINCT
10139
** METHOD: sqlite3_index_info
10140
**
10141
** This API may only be used from within an [xBestIndex|xBestIndex method]
10142
** of a [virtual table] implementation. The result of calling this
10143
** interface from outside of xBestIndex() is undefined and probably harmful.
10144
**
10145
** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and
10146
** 3.  The integer returned by sqlite3_vtab_distinct()
10147
** gives the virtual table additional information about how the query
10148
** planner wants the output to be ordered. As long as the virtual table
10149
** can meet the ordering requirements of the query planner, it may set
10150
** the "orderByConsumed" flag.
10151
**
10152
** <ol><li value="0"><p>
10153
** ^If the sqlite3_vtab_distinct() interface returns 0, that means
10154
** that the query planner needs the virtual table to return all rows in the
10155
** sort order defined by the "nOrderBy" and "aOrderBy" fields of the
10156
** [sqlite3_index_info] object.  This is the default expectation.  If the
10157
** virtual table outputs all rows in sorted order, then it is always safe for
10158
** the xBestIndex method to set the "orderByConsumed" flag, regardless of
10159
** the return value from sqlite3_vtab_distinct().
10160
** <li value="1"><p>
10161
** ^(If the sqlite3_vtab_distinct() interface returns 1, that means
10162
** that the query planner does not need the rows to be returned in sorted order
10163
** as long as all rows with the same values in all columns identified by the
10164
** "aOrderBy" field are adjacent.)^  This mode is used when the query planner
10165
** is doing a GROUP BY.
10166
** <li value="2"><p>
10167
** ^(If the sqlite3_vtab_distinct() interface returns 2, that means
10168
** that the query planner does not need the rows returned in any particular
10169
** order, as long as rows with the same values in all columns identified
10170
** by "aOrderBy" are adjacent.)^  ^(Furthermore, when two or more rows
10171
** contain the same values for all columns identified by "colUsed", all but
10172
** one such row may optionally be omitted from the result.)^
10173
** The virtual table is not required to omit rows that are duplicates
10174
** over the "colUsed" columns, but if the virtual table can do that without
10175
** too much extra effort, it could potentially help the query to run faster.
10176
** This mode is used for a DISTINCT query.
10177
** <li value="3"><p>
10178
** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the
10179
** virtual table must return rows in the order defined by "aOrderBy" as
10180
** if the sqlite3_vtab_distinct() interface had returned 0.  However if
10181
** two or more rows in the result have the same values for all columns
10182
** identified by "colUsed", then all but one such row may optionally be
10183
** omitted.)^  Like when the return value is 2, the virtual table
10184
** is not required to omit rows that are duplicates over the "colUsed"
10185
** columns, but if the virtual table can do that without
10186
** too much extra effort, it could potentially help the query to run faster.
10187
** This mode is used for queries
10188
** that have both DISTINCT and ORDER BY clauses.
10189
** </ol>
10190
**
10191
** <p>The following table summarizes the conditions under which the
10192
** virtual table is allowed to set the "orderByConsumed" flag based on
10193
** the value returned by sqlite3_vtab_distinct().  This table is a
10194
** restatement of the previous four paragraphs:
10195
**
10196
** <table border=1 cellspacing=0 cellpadding=10 width="90%">
10197
** <tr>
10198
** <td valign="top">sqlite3_vtab_distinct() return value
10199
** <td valign="top">Rows are returned in aOrderBy order
10200
** <td valign="top">Rows with the same value in all aOrderBy columns are adjacent
10201
** <td valign="top">Duplicates over all colUsed columns may be omitted
10202
** <tr><td>0<td>yes<td>yes<td>no
10203
** <tr><td>1<td>no<td>yes<td>no
10204
** <tr><td>2<td>no<td>yes<td>yes
10205
** <tr><td>3<td>yes<td>yes<td>yes
10206
** </table>
10207
**
10208
** ^For the purposes of comparing virtual table output values to see if the
10209
** values are the same value for sorting purposes, two NULL values are considered
10210
** to be the same.  In other words, the comparison operator is "IS"
10211
** (or "IS NOT DISTINCT FROM") and not "==".
10212
**
10213
** If a virtual table implementation is unable to meet the requirements
10214
** specified above, then it must not set the "orderByConsumed" flag in the
10215
** [sqlite3_index_info] object or an incorrect answer may result.
10216
**
10217
** ^A virtual table implementation is always free to return rows in any order
10218
** it wants, as long as the "orderByConsumed" flag is not set.  ^When the
10219
** "orderByConsumed" flag is unset, the query planner will add extra
10220
** [bytecode] to ensure that the final results returned by the SQL query are
10221
** ordered correctly.  The use of the "orderByConsumed" flag and the
10222
** sqlite3_vtab_distinct() interface is merely an optimization.  ^Careful
10223
** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed"
10224
** flag might help queries against a virtual table to run faster.  Being
10225
** overly aggressive and setting the "orderByConsumed" flag when it is not
10226
** valid to do so, on the other hand, might cause SQLite to return incorrect
10227
** results.
10228
*/
10229
SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*);
10230
10231
/*
10232
** CAPI3REF: Identify and handle IN constraints in xBestIndex
10233
**
10234
** This interface may only be used from within an
10235
** [xBestIndex|xBestIndex() method] of a [virtual table] implementation.
10236
** The result of invoking this interface from any other context is
10237
** undefined and probably harmful.
10238
**
10239
** ^(A constraint on a virtual table of the form
10240
** "[IN operator|column IN (...)]" is
10241
** communicated to the xBestIndex method as a
10242
** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^  If xBestIndex wants to use
10243
** this constraint, it must set the corresponding
10244
** aConstraintUsage[].argvIndex to a positive integer.  ^(Then, under
10245
** the usual mode of handling IN operators, SQLite generates [bytecode]
10246
** that invokes the [xFilter|xFilter() method] once for each value
10247
** on the right-hand side of the IN operator.)^  Thus the virtual table
10248
** only sees a single value from the right-hand side of the IN operator
10249
** at a time.
10250
**
10251
** In some cases, however, it would be advantageous for the virtual
10252
** table to see all values on the right-hand of the IN operator all at
10253
** once.  The sqlite3_vtab_in() interfaces facilitates this in two ways:
10254
**
10255
** <ol>
10256
** <li><p>
10257
**   ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero)
10258
**   if and only if the [sqlite3_index_info|P->aConstraint][N] constraint
10259
**   is an [IN operator] that can be processed all at once.  ^In other words,
10260
**   sqlite3_vtab_in() with -1 in the third argument is a mechanism
10261
**   by which the virtual table can ask SQLite if all-at-once processing
10262
**   of the IN operator is even possible.
10263
**
10264
** <li><p>
10265
**   ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates
10266
**   to SQLite that the virtual table does or does not want to process
10267
**   the IN operator all-at-once, respectively.  ^Thus when the third
10268
**   parameter (F) is non-negative, this interface is the mechanism by
10269
**   which the virtual table tells SQLite how it wants to process the
10270
**   IN operator.
10271
** </ol>
10272
**
10273
** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times
10274
** within the same xBestIndex method call.  ^For any given P,N pair,
10275
** the return value from sqlite3_vtab_in(P,N,F) will always be the same
10276
** within the same xBestIndex call.  ^If the interface returns true
10277
** (non-zero), that means that the constraint is an IN operator
10278
** that can be processed all-at-once.  ^If the constraint is not an IN
10279
** operator or cannot be processed all-at-once, then the interface returns
10280
** false.
10281
**
10282
** ^(All-at-once processing of the IN operator is selected if both of the
10283
** following conditions are met:
10284
**
10285
** <ol>
10286
** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive
10287
** integer.  This is how the virtual table tells SQLite that it wants to
10288
** use the N-th constraint.
10289
**
10290
** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was
10291
** non-negative had F>=1.
10292
** </ol>)^
10293
**
10294
** ^If either or both of the conditions above are false, then SQLite uses
10295
** the traditional one-at-a-time processing strategy for the IN constraint.
10296
** ^If both conditions are true, then the argvIndex-th parameter to the
10297
** xFilter method will be an [sqlite3_value] that appears to be NULL,
10298
** but which can be passed to [sqlite3_vtab_in_first()] and
10299
** [sqlite3_vtab_in_next()] to find all values on the right-hand side
10300
** of the IN constraint.
10301
*/
10302
SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle);
10303
10304
/*
10305
** CAPI3REF: Find all elements on the right-hand side of an IN constraint.
10306
**
10307
** These interfaces are only useful from within the
10308
** [xFilter|xFilter() method] of a [virtual table] implementation.
10309
** The result of invoking these interfaces from any other context
10310
** is undefined and probably harmful.
10311
**
10312
** The X parameter in a call to sqlite3_vtab_in_first(X,P) or
10313
** sqlite3_vtab_in_next(X,P) should be one of the parameters to the
10314
** xFilter method which invokes these routines, and specifically
10315
** a parameter that was previously selected for all-at-once IN constraint
10316
** processing using the [sqlite3_vtab_in()] interface in the
10317
** [xBestIndex|xBestIndex method].  ^(If the X parameter is not
10318
** an xFilter argument that was selected for all-at-once IN constraint
10319
** processing, then these routines return [SQLITE_ERROR].)^
10320
**
10321
** ^(Use these routines to access all values on the right-hand side
10322
** of the IN constraint using code like the following:
10323
**
10324
** <blockquote><pre>
10325
** &nbsp;  for(rc=sqlite3_vtab_in_first(pList, &pVal);
10326
** &nbsp;      rc==SQLITE_OK && pVal;
10327
** &nbsp;      rc=sqlite3_vtab_in_next(pList, &pVal)
10328
** &nbsp;  ){
10329
** &nbsp;    // do something with pVal
10330
** &nbsp;  }
10331
** &nbsp;  if( rc!=SQLITE_OK ){
10332
** &nbsp;    // an error has occurred
10333
** &nbsp;  }
10334
** </pre></blockquote>)^
10335
**
10336
** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P)
10337
** routines return SQLITE_OK and set *P to point to the first or next value
10338
** on the RHS of the IN constraint.  ^If there are no more values on the
10339
** right hand side of the IN constraint, then *P is set to NULL and these
10340
** routines return [SQLITE_DONE].  ^The return value might be
10341
** some other value, such as SQLITE_NOMEM, in the event of a malfunction.
10342
**
10343
** The *ppOut values returned by these routines are only valid until the
10344
** next call to either of these routines or until the end of the xFilter
10345
** method from which these routines were called.  If the virtual table
10346
** implementation needs to retain the *ppOut values for longer, it must make
10347
** copies.  The *ppOut values are [protected sqlite3_value|protected].
10348
*/
10349
SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut);
10350
SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut);
10351
10352
/*
10353
** CAPI3REF: Constraint values in xBestIndex()
10354
** METHOD: sqlite3_index_info
10355
**
10356
** This API may only be used from within the [xBestIndex|xBestIndex method]
10357
** of a [virtual table] implementation. The result of calling this interface
10358
** from outside of an xBestIndex method are undefined and probably harmful.
10359
**
10360
** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within
10361
** the [xBestIndex] method of a [virtual table] implementation, with P being
10362
** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and
10363
** J being a 0-based index into P->aConstraint[], then this routine
10364
** attempts to set *V to the value of the right-hand operand of
10365
** that constraint if the right-hand operand is known.  ^If the
10366
** right-hand operand is not known, then *V is set to a NULL pointer.
10367
** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if
10368
** and only if *V is set to a value.  ^The sqlite3_vtab_rhs_value(P,J,V)
10369
** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th
10370
** constraint is not available.  ^The sqlite3_vtab_rhs_value() interface
10371
** can return a result code other than SQLITE_OK or SQLITE_NOTFOUND if
10372
** something goes wrong.
10373
**
10374
** The sqlite3_vtab_rhs_value() interface is usually only successful if
10375
** the right-hand operand of a constraint is a literal value in the original
10376
** SQL statement.  If the right-hand operand is an expression or a reference
10377
** to some other column or a [host parameter], then sqlite3_vtab_rhs_value()
10378
** will probably return [SQLITE_NOTFOUND].
10379
**
10380
** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and
10381
** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand.  For such
10382
** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^
10383
**
10384
** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value
10385
** and remains valid for the duration of the xBestIndex method call.
10386
** ^When xBestIndex returns, the sqlite3_value object returned by
10387
** sqlite3_vtab_rhs_value() is automatically deallocated.
10388
**
10389
** The "_rhs_" in the name of this routine is an abbreviation for
10390
** "Right-Hand Side".
10391
*/
10392
SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal);
10393
10394
/*
10395
** CAPI3REF: Conflict resolution modes
10396
** KEYWORDS: {conflict resolution mode}
10397
**
10398
** These constants are returned by [sqlite3_vtab_on_conflict()] to
10399
** inform a [virtual table] implementation of the [ON CONFLICT] mode
10400
** for the SQL statement being evaluated.
10401
**
10402
** Note that the [SQLITE_IGNORE] constant is also used as a potential
10403
** return value from the [sqlite3_set_authorizer()] callback and that
10404
** [SQLITE_ABORT] is also a [result code].
10405
*/
10406
#define SQLITE_ROLLBACK 1
10407
/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
10408
#define SQLITE_FAIL     3
10409
/* #define SQLITE_ABORT 4  // Also an error code */
10410
#define SQLITE_REPLACE  5
10411
10412
/*
10413
** CAPI3REF: Prepared Statement Scan Status Opcodes
10414
** KEYWORDS: {scanstatus options}
10415
**
10416
** The following constants can be used for the T parameter to the
10417
** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
10418
** different metric for sqlite3_stmt_scanstatus() to return.
10419
**
10420
** When the value returned to V is a string, space to hold that string is
10421
** managed by the prepared statement S and will be automatically freed when
10422
** S is finalized.
10423
**
10424
** Not all values are available for all query elements. When a value is
10425
** not available, the output variable is set to -1 if the value is numeric,
10426
** or to NULL if it is a string (SQLITE_SCANSTAT_NAME).
10427
**
10428
** <dl>
10429
** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
10430
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be
10431
** set to the total number of times that the X-th loop has run.</dd>
10432
**
10433
** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
10434
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set
10435
** to the total number of rows examined by all iterations of the X-th loop.</dd>
10436
**
10437
** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
10438
** <dd>^The "double" variable pointed to by the V parameter will be set to the
10439
** query planner's estimate for the average number of rows output from each
10440
** iteration of the X-th loop.  If the query planner's estimate was accurate,
10441
** then this value will approximate the quotient NVISIT/NLOOP and the
10442
** product of this value for all prior loops with the same SELECTID will
10443
** be the NLOOP value for the current loop.</dd>
10444
**
10445
** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
10446
** <dd>^The "const char *" variable pointed to by the V parameter will be set
10447
** to a zero-terminated UTF-8 string containing the name of the index or table
10448
** used for the X-th loop.</dd>
10449
**
10450
** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
10451
** <dd>^The "const char *" variable pointed to by the V parameter will be set
10452
** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
10453
** description for the X-th loop.</dd>
10454
**
10455
** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECTID</dt>
10456
** <dd>^The "int" variable pointed to by the V parameter will be set to the
10457
** id for the X-th query plan element. The id value is unique within the
10458
** statement. The select-id is the same value as is output in the first
10459
** column of an [EXPLAIN QUERY PLAN] query.</dd>
10460
**
10461
** [[SQLITE_SCANSTAT_PARENTID]] <dt>SQLITE_SCANSTAT_PARENTID</dt>
10462
** <dd>The "int" variable pointed to by the V parameter will be set to the
10463
** id of the parent of the current query element, if applicable, or
10464
** to zero if the query element has no parent. This is the same value as
10465
** returned in the second column of an [EXPLAIN QUERY PLAN] query.</dd>
10466
**
10467
** [[SQLITE_SCANSTAT_NCYCLE]] <dt>SQLITE_SCANSTAT_NCYCLE</dt>
10468
** <dd>The sqlite3_int64 output value is set to the number of cycles,
10469
** according to the processor time-stamp counter, that elapsed while the
10470
** query element was being processed. This value is not available for
10471
** all query elements - if it is unavailable the output variable is
10472
** set to -1.</dd>
10473
** </dl>
10474
*/
10475
#define SQLITE_SCANSTAT_NLOOP    0
10476
#define SQLITE_SCANSTAT_NVISIT   1
10477
#define SQLITE_SCANSTAT_EST      2
10478
#define SQLITE_SCANSTAT_NAME     3
10479
#define SQLITE_SCANSTAT_EXPLAIN  4
10480
#define SQLITE_SCANSTAT_SELECTID 5
10481
#define SQLITE_SCANSTAT_PARENTID 6
10482
#define SQLITE_SCANSTAT_NCYCLE   7
10483
10484
/*
10485
** CAPI3REF: Prepared Statement Scan Status
10486
** METHOD: sqlite3_stmt
10487
**
10488
** These interfaces return information about the predicted and measured
10489
** performance for pStmt.  Advanced applications can use this
10490
** interface to compare the predicted and the measured performance and
10491
** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
10492
**
10493
** Since this interface is expected to be rarely used, it is only
10494
** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
10495
** compile-time option.
10496
**
10497
** The "iScanStatusOp" parameter determines which status information to return.
10498
** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
10499
** of this interface is undefined. ^The requested measurement is written into
10500
** a variable pointed to by the "pOut" parameter.
10501
**
10502
** The "flags" parameter must be passed a mask of flags. At present only
10503
** one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX
10504
** is specified, then status information is available for all elements
10505
** of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If
10506
** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements
10507
** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of
10508
** the EXPLAIN QUERY PLAN output) are available. Invoking API
10509
** sqlite3_stmt_scanstatus() is equivalent to calling
10510
** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter.
10511
**
10512
** Parameter "idx" identifies the specific query element to retrieve statistics
10513
** for. Query elements are numbered starting from zero. A value of -1 may
10514
** retrieve statistics for the entire query. ^If idx is out of range
10515
** - less than -1 or greater than or equal to the total number of query
10516
** elements used to implement the statement - a non-zero value is returned and
10517
** the variable that pOut points to is unchanged.
10518
**
10519
** See also: [sqlite3_stmt_scanstatus_reset()]
10520
*/
10521
SQLITE_API int sqlite3_stmt_scanstatus(
10522
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
10523
  int idx,                  /* Index of loop to report on */
10524
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
10525
  void *pOut                /* Result written here */
10526
);
10527
SQLITE_API int sqlite3_stmt_scanstatus_v2(
10528
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
10529
  int idx,                  /* Index of loop to report on */
10530
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
10531
  int flags,                /* Mask of flags defined below */
10532
  void *pOut                /* Result written here */
10533
);
10534
10535
/*
10536
** CAPI3REF: Prepared Statement Scan Status
10537
** KEYWORDS: {scan status flags}
10538
*/
10539
#define SQLITE_SCANSTAT_COMPLEX 0x0001
10540
10541
/*
10542
** CAPI3REF: Zero Scan-Status Counters
10543
** METHOD: sqlite3_stmt
10544
**
10545
** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
10546
**
10547
** This API is only available if the library is built with pre-processor
10548
** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
10549
*/
10550
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
10551
10552
/*
10553
** CAPI3REF: Flush caches to disk mid-transaction
10554
** METHOD: sqlite3
10555
**
10556
** ^If a write-transaction is open on [database connection] D when the
10557
** [sqlite3_db_cacheflush(D)] interface is invoked, any dirty
10558
** pages in the pager-cache that are not currently in use are written out
10559
** to disk. A dirty page may be in use if a database cursor created by an
10560
** active SQL statement is reading from it, or if it is page 1 of a database
10561
** file (page 1 is always "in use").  ^The [sqlite3_db_cacheflush(D)]
10562
** interface flushes caches for all schemas - "main", "temp", and
10563
** any [attached] databases.
10564
**
10565
** ^If this function needs to obtain extra database locks before dirty pages
10566
** can be flushed to disk, it does so. ^If those locks cannot be obtained
10567
** immediately and there is a busy-handler callback configured, it is invoked
10568
** in the usual manner. ^If the required lock still cannot be obtained, then
10569
** the database is skipped and an attempt made to flush any dirty pages
10570
** belonging to the next (if any) database. ^If any databases are skipped
10571
** because locks cannot be obtained, but no other error occurs, this
10572
** function returns SQLITE_BUSY.
10573
**
10574
** ^If any other error occurs while flushing dirty pages to disk (for
10575
** example an IO error or out-of-memory condition), then processing is
10576
** abandoned and an SQLite [error code] is returned to the caller immediately.
10577
**
10578
** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
10579
**
10580
** ^This function does not set the database handle error code or message
10581
** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
10582
*/
10583
SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
10584
10585
/*
10586
** CAPI3REF: The pre-update hook.
10587
** METHOD: sqlite3
10588
**
10589
** ^These interfaces are only available if SQLite is compiled using the
10590
** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
10591
**
10592
** ^The [sqlite3_preupdate_hook()] interface registers a callback function
10593
** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
10594
** on a database table.
10595
** ^At most one preupdate hook may be registered at a time on a single
10596
** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
10597
** the previous setting.
10598
** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
10599
** with a NULL pointer as the second parameter.
10600
** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
10601
** the first parameter to callbacks.
10602
**
10603
** ^The preupdate hook only fires for changes to real database tables; the
10604
** preupdate hook is not invoked for changes to [virtual tables] or to
10605
** system tables like sqlite_sequence or sqlite_stat1.
10606
**
10607
** ^The second parameter to the preupdate callback is a pointer to
10608
** the [database connection] that registered the preupdate hook.
10609
** ^The third parameter to the preupdate callback is one of the constants
10610
** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
10611
** kind of update operation that is about to occur.
10612
** ^(The fourth parameter to the preupdate callback is the name of the
10613
** database within the database connection that is being modified.  This
10614
** will be "main" for the main database or "temp" for TEMP tables or
10615
** the name given after the AS keyword in the [ATTACH] statement for attached
10616
** databases.)^
10617
** ^The fifth parameter to the preupdate callback is the name of the
10618
** table that is being modified.
10619
**
10620
** For an UPDATE or DELETE operation on a [rowid table], the sixth
10621
** parameter passed to the preupdate callback is the initial [rowid] of the
10622
** row being modified or deleted. For an INSERT operation on a rowid table,
10623
** or any operation on a WITHOUT ROWID table, the value of the sixth
10624
** parameter is undefined. For an INSERT or UPDATE on a rowid table the
10625
** seventh parameter is the final rowid value of the row being inserted
10626
** or updated. The value of the seventh parameter passed to the callback
10627
** function is not defined for operations on WITHOUT ROWID tables, or for
10628
** DELETE operations on rowid tables.
10629
**
10630
** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from
10631
** the previous call on the same [database connection] D, or NULL for
10632
** the first call on D.
10633
**
10634
** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
10635
** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
10636
** provide additional information about a preupdate event. These routines
10637
** may only be called from within a preupdate callback.  Invoking any of
10638
** these routines from outside of a preupdate callback or with a
10639
** [database connection] pointer that is different from the one supplied
10640
** to the preupdate callback results in undefined and probably undesirable
10641
** behavior.
10642
**
10643
** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
10644
** in the row that is being inserted, updated, or deleted.
10645
**
10646
** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
10647
** a [protected sqlite3_value] that contains the value of the Nth column of
10648
** the table row before it is updated.  The N parameter must be between 0
10649
** and one less than the number of columns or the behavior will be
10650
** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
10651
** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
10652
** behavior is undefined.  The [sqlite3_value] that P points to
10653
** will be destroyed when the preupdate callback returns.
10654
**
10655
** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
10656
** a [protected sqlite3_value] that contains the value of the Nth column of
10657
** the table row after it is updated.  The N parameter must be between 0
10658
** and one less than the number of columns or the behavior will be
10659
** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
10660
** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
10661
** behavior is undefined.  The [sqlite3_value] that P points to
10662
** will be destroyed when the preupdate callback returns.
10663
**
10664
** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
10665
** callback was invoked as a result of a direct insert, update, or delete
10666
** operation; or 1 for inserts, updates, or deletes invoked by top-level
10667
** triggers; or 2 for changes resulting from triggers called by top-level
10668
** triggers; and so forth.
10669
**
10670
** When the [sqlite3_blob_write()] API is used to update a blob column,
10671
** the pre-update hook is invoked with SQLITE_DELETE, because
10672
** the new values are not yet available. In this case, when a
10673
** callback made with op==SQLITE_DELETE is actually a write using the
10674
** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns
10675
** the index of the column being written. In other cases, where the
10676
** pre-update hook is being invoked for some other reason, including a
10677
** regular DELETE, sqlite3_preupdate_blobwrite() returns -1.
10678
**
10679
** See also:  [sqlite3_update_hook()]
10680
*/
10681
#if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
10682
SQLITE_API void *sqlite3_preupdate_hook(
10683
  sqlite3 *db,
10684
  void(*xPreUpdate)(
10685
    void *pCtx,                   /* Copy of third arg to preupdate_hook() */
10686
    sqlite3 *db,                  /* Database handle */
10687
    int op,                       /* SQLITE_UPDATE, DELETE or INSERT */
10688
    char const *zDb,              /* Database name */
10689
    char const *zName,            /* Table name */
10690
    sqlite3_int64 iKey1,          /* Rowid of row about to be deleted/updated */
10691
    sqlite3_int64 iKey2           /* New rowid value (for a rowid UPDATE) */
10692
  ),
10693
  void*
10694
);
10695
SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
10696
SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
10697
SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
10698
SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
10699
SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *);
10700
#endif
10701
10702
/*
10703
** CAPI3REF: Low-level system error code
10704
** METHOD: sqlite3
10705
**
10706
** ^Attempt to return the underlying operating system error code or error
10707
** number that caused the most recent I/O error or failure to open a file.
10708
** The return value is OS-dependent.  For example, on unix systems, after
10709
** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
10710
** called to get back the underlying "errno" that caused the problem, such
10711
** as ENOSPC, EAUTH, EISDIR, and so forth.
10712
*/
10713
SQLITE_API int sqlite3_system_errno(sqlite3*);
10714
10715
/*
10716
** CAPI3REF: Database Snapshot
10717
** KEYWORDS: {snapshot} {sqlite3_snapshot}
10718
**
10719
** An instance of the snapshot object records the state of a [WAL mode]
10720
** database for some specific point in history.
10721
**
10722
** In [WAL mode], multiple [database connections] that are open on the
10723
** same database file can each be reading a different historical version
10724
** of the database file.  When a [database connection] begins a read
10725
** transaction, that connection sees an unchanging copy of the database
10726
** as it existed for the point in time when the transaction first started.
10727
** Subsequent changes to the database from other connections are not seen
10728
** by the reader until a new read transaction is started.
10729
**
10730
** The sqlite3_snapshot object records state information about an historical
10731
** version of the database file so that it is possible to later open a new read
10732
** transaction that sees that historical version of the database rather than
10733
** the most recent version.
10734
*/
10735
typedef struct sqlite3_snapshot {
10736
  unsigned char hidden[48];
10737
} sqlite3_snapshot;
10738
10739
/*
10740
** CAPI3REF: Record A Database Snapshot
10741
** CONSTRUCTOR: sqlite3_snapshot
10742
**
10743
** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
10744
** new [sqlite3_snapshot] object that records the current state of
10745
** schema S in database connection D.  ^On success, the
10746
** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
10747
** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
10748
** If there is not already a read-transaction open on schema S when
10749
** this function is called, one is opened automatically.
10750
**
10751
** If a read-transaction is opened by this function, then it is guaranteed
10752
** that the returned snapshot object may not be invalidated by a database
10753
** writer or checkpointer until after the read-transaction is closed. This
10754
** is not guaranteed if a read-transaction is already open when this
10755
** function is called. In that case, any subsequent write or checkpoint
10756
** operation on the database may invalidate the returned snapshot handle,
10757
** even while the read-transaction remains open.
10758
**
10759
** The following must be true for this function to succeed. If any of
10760
** the following statements are false when sqlite3_snapshot_get() is
10761
** called, SQLITE_ERROR is returned. The final value of *P is undefined
10762
** in this case.
10763
**
10764
** <ul>
10765
**   <li> The database handle must not be in [autocommit mode].
10766
**
10767
**   <li> Schema S of [database connection] D must be a [WAL mode] database.
10768
**
10769
**   <li> There must not be a write transaction open on schema S of database
10770
**        connection D.
10771
**
10772
**   <li> One or more transactions must have been written to the current wal
10773
**        file since it was created on disk (by any connection). This means
10774
**        that a snapshot cannot be taken on a wal mode database with no wal
10775
**        file immediately after it is first opened. At least one transaction
10776
**        must be written to it first.
10777
** </ul>
10778
**
10779
** This function may also return SQLITE_NOMEM.  If it is called with the
10780
** database handle in autocommit mode but fails for some other reason,
10781
** whether or not a read transaction is opened on schema S is undefined.
10782
**
10783
** The [sqlite3_snapshot] object returned from a successful call to
10784
** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
10785
** to avoid a memory leak.
10786
**
10787
** The [sqlite3_snapshot_get()] interface is only available when the
10788
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10789
*/
10790
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
10791
  sqlite3 *db,
10792
  const char *zSchema,
10793
  sqlite3_snapshot **ppSnapshot
10794
);
10795
10796
/*
10797
** CAPI3REF: Start a read transaction on an historical snapshot
10798
** METHOD: sqlite3_snapshot
10799
**
10800
** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read
10801
** transaction or upgrades an existing one for schema S of
10802
** [database connection] D such that the read transaction refers to
10803
** historical [snapshot] P, rather than the most recent change to the
10804
** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK
10805
** on success or an appropriate [error code] if it fails.
10806
**
10807
** ^In order to succeed, the database connection must not be in
10808
** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there
10809
** is already a read transaction open on schema S, then the database handle
10810
** must have no active statements (SELECT statements that have been passed
10811
** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()).
10812
** SQLITE_ERROR is returned if either of these conditions is violated, or
10813
** if schema S does not exist, or if the snapshot object is invalid.
10814
**
10815
** ^A call to sqlite3_snapshot_open() will fail to open if the specified
10816
** snapshot has been overwritten by a [checkpoint]. In this case
10817
** SQLITE_ERROR_SNAPSHOT is returned.
10818
**
10819
** If there is already a read transaction open when this function is
10820
** invoked, then the same read transaction remains open (on the same
10821
** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT
10822
** is returned. If another error code - for example SQLITE_PROTOCOL or an
10823
** SQLITE_IOERR error code - is returned, then the final state of the
10824
** read transaction is undefined. If SQLITE_OK is returned, then the
10825
** read transaction is now open on database snapshot P.
10826
**
10827
** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
10828
** database connection D does not know that the database file for
10829
** schema S is in [WAL mode].  A database connection might not know
10830
** that the database file is in [WAL mode] if there has been no prior
10831
** I/O on that database connection, or if the database entered [WAL mode]
10832
** after the most recent I/O on the database connection.)^
10833
** (Hint: Run "[PRAGMA application_id]" against a newly opened
10834
** database connection in order to make it ready to use snapshots.)
10835
**
10836
** The [sqlite3_snapshot_open()] interface is only available when the
10837
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10838
*/
10839
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
10840
  sqlite3 *db,
10841
  const char *zSchema,
10842
  sqlite3_snapshot *pSnapshot
10843
);
10844
10845
/*
10846
** CAPI3REF: Destroy a snapshot
10847
** DESTRUCTOR: sqlite3_snapshot
10848
**
10849
** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
10850
** The application must eventually free every [sqlite3_snapshot] object
10851
** using this routine to avoid a memory leak.
10852
**
10853
** The [sqlite3_snapshot_free()] interface is only available when the
10854
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10855
*/
10856
SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
10857
10858
/*
10859
** CAPI3REF: Compare the ages of two snapshot handles.
10860
** METHOD: sqlite3_snapshot
10861
**
10862
** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
10863
** of two valid snapshot handles.
10864
**
10865
** If the two snapshot handles are not associated with the same database
10866
** file, the result of the comparison is undefined.
10867
**
10868
** Additionally, the result of the comparison is only valid if both of the
10869
** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
10870
** last time the wal file was deleted. The wal file is deleted when the
10871
** database is changed back to rollback mode or when the number of database
10872
** clients drops to zero. If either snapshot handle was obtained before the
10873
** wal file was last deleted, the value returned by this function
10874
** is undefined.
10875
**
10876
** Otherwise, this API returns a negative value if P1 refers to an older
10877
** snapshot than P2, zero if the two handles refer to the same database
10878
** snapshot, and a positive value if P1 is a newer snapshot than P2.
10879
**
10880
** This interface is only available if SQLite is compiled with the
10881
** [SQLITE_ENABLE_SNAPSHOT] option.
10882
*/
10883
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
10884
  sqlite3_snapshot *p1,
10885
  sqlite3_snapshot *p2
10886
);
10887
10888
/*
10889
** CAPI3REF: Recover snapshots from a wal file
10890
** METHOD: sqlite3_snapshot
10891
**
10892
** If a [WAL file] remains on disk after all database connections close
10893
** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control]
10894
** or because the last process to have the database opened exited without
10895
** calling [sqlite3_close()]) and a new connection is subsequently opened
10896
** on that database and [WAL file], the [sqlite3_snapshot_open()] interface
10897
** will only be able to open the last transaction added to the WAL file
10898
** even though the WAL file contains other valid transactions.
10899
**
10900
** This function attempts to scan the WAL file associated with database zDb
10901
** of database handle db and make all valid snapshots available to
10902
** sqlite3_snapshot_open(). It is an error if there is already a read
10903
** transaction open on the database, or if the database is not a WAL mode
10904
** database.
10905
**
10906
** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
10907
**
10908
** This interface is only available if SQLite is compiled with the
10909
** [SQLITE_ENABLE_SNAPSHOT] option.
10910
*/
10911
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
10912
10913
/*
10914
** CAPI3REF: Serialize a database
10915
**
10916
** The sqlite3_serialize(D,S,P,F) interface returns a pointer to
10917
** memory that is a serialization of the S database on
10918
** [database connection] D.  If S is a NULL pointer, the main database is used.
10919
** If P is not a NULL pointer, then the size of the database in bytes
10920
** is written into *P.
10921
**
10922
** For an ordinary on-disk database file, the serialization is just a
10923
** copy of the disk file.  For an in-memory database or a "TEMP" database,
10924
** the serialization is the same sequence of bytes which would be written
10925
** to disk if that database were backed up to disk.
10926
**
10927
** The usual case is that sqlite3_serialize() copies the serialization of
10928
** the database into memory obtained from [sqlite3_malloc64()] and returns
10929
** a pointer to that memory.  The caller is responsible for freeing the
10930
** returned value to avoid a memory leak.  However, if the F argument
10931
** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
10932
** are made, and the sqlite3_serialize() function will return a pointer
10933
** to the contiguous memory representation of the database that SQLite
10934
** is currently using for that database, or NULL if no such contiguous
10935
** memory representation of the database exists.  A contiguous memory
10936
** representation of the database will usually only exist if there has
10937
** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
10938
** values of D and S.
10939
** The size of the database is written into *P even if the
10940
** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy
10941
** of the database exists.
10942
**
10943
** After the call, if the SQLITE_SERIALIZE_NOCOPY bit had been set,
10944
** the returned buffer content will remain accessible and unchanged
10945
** until either the next write operation on the connection or when
10946
** the connection is closed, and applications must not modify the
10947
** buffer. If the bit had been clear, the returned buffer will not
10948
** be accessed by SQLite after the call.
10949
**
10950
** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
10951
** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
10952
** allocation error occurs.
10953
**
10954
** This interface is omitted if SQLite is compiled with the
10955
** [SQLITE_OMIT_DESERIALIZE] option.
10956
*/
10957
SQLITE_API unsigned char *sqlite3_serialize(
10958
  sqlite3 *db,           /* The database connection */
10959
  const char *zSchema,   /* Which DB to serialize. ex: "main", "temp", ... */
10960
  sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
10961
  unsigned int mFlags    /* Zero or more SQLITE_SERIALIZE_* flags */
10962
);
10963
10964
/*
10965
** CAPI3REF: Flags for sqlite3_serialize
10966
**
10967
** Zero or more of the following constants can be OR-ed together for
10968
** the F argument to [sqlite3_serialize(D,S,P,F)].
10969
**
10970
** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return
10971
** a pointer to contiguous in-memory database that it is currently using,
10972
** without making a copy of the database.  If SQLite is not currently using
10973
** a contiguous in-memory database, then this option causes
10974
** [sqlite3_serialize()] to return a NULL pointer.  SQLite will only be
10975
** using a contiguous in-memory database if it has been initialized by a
10976
** prior call to [sqlite3_deserialize()].
10977
*/
10978
#define SQLITE_SERIALIZE_NOCOPY 0x001   /* Do no memory allocations */
10979
10980
/*
10981
** CAPI3REF: Deserialize a database
10982
**
10983
** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the
10984
** [database connection] D to disconnect from database S and then
10985
** reopen S as an in-memory database based on the serialization contained
10986
** in P.  The serialized database P is N bytes in size.  M is the size of
10987
** the buffer P, which might be larger than N.  If M is larger than N, and
10988
** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is
10989
** permitted to add content to the in-memory database as long as the total
10990
** size does not exceed M bytes.
10991
**
10992
** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
10993
** invoke sqlite3_free() on the serialization buffer when the database
10994
** connection closes.  If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
10995
** SQLite will try to increase the buffer size using sqlite3_realloc64()
10996
** if writes on the database cause it to grow larger than M bytes.
10997
**
10998
** Applications must not modify the buffer P or invalidate it before
10999
** the database connection D is closed.
11000
**
11001
** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
11002
** database is currently in a read transaction or is involved in a backup
11003
** operation.
11004
**
11005
** It is not possible to deserialize into the TEMP database.  If the
11006
** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the
11007
** function returns SQLITE_ERROR.
11008
**
11009
** The deserialized database should not be in [WAL mode].  If the database
11010
** is in WAL mode, then any attempt to use the database file will result
11011
** in an [SQLITE_CANTOPEN] error.  The application can set the
11012
** [file format version numbers] (bytes 18 and 19) of the input database P
11013
** to 0x01 prior to invoking sqlite3_deserialize(D,S,P,N,M,F) to force the
11014
** database file into rollback mode and work around this limitation.
11015
**
11016
** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the
11017
** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
11018
** [sqlite3_free()] is invoked on argument P prior to returning.
11019
**
11020
** This interface is omitted if SQLite is compiled with the
11021
** [SQLITE_OMIT_DESERIALIZE] option.
11022
*/
11023
SQLITE_API int sqlite3_deserialize(
11024
  sqlite3 *db,            /* The database connection */
11025
  const char *zSchema,    /* Which DB to reopen with the deserialization */
11026
  unsigned char *pData,   /* The serialized database content */
11027
  sqlite3_int64 szDb,     /* Number of bytes in the deserialization */
11028
  sqlite3_int64 szBuf,    /* Total size of buffer pData[] */
11029
  unsigned mFlags         /* Zero or more SQLITE_DESERIALIZE_* flags */
11030
);
11031
11032
/*
11033
** CAPI3REF: Flags for sqlite3_deserialize()
11034
**
11035
** The following are allowed values for the 6th argument (the F argument) to
11036
** the [sqlite3_deserialize(D,S,P,N,M,F)] interface.
11037
**
11038
** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization
11039
** in the P argument is held in memory obtained from [sqlite3_malloc64()]
11040
** and that SQLite should take ownership of this memory and automatically
11041
** free it when it has finished using it.  Without this flag, the caller
11042
** is responsible for freeing any dynamically allocated memory.
11043
**
11044
** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to
11045
** grow the size of the database using calls to [sqlite3_realloc64()].  This
11046
** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used.
11047
** Without this flag, the deserialized database cannot increase in size beyond
11048
** the number of bytes specified by the M parameter.
11049
**
11050
** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database
11051
** should be treated as read-only.
11052
*/
11053
#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
11054
#define SQLITE_DESERIALIZE_RESIZEABLE  2 /* Resize using sqlite3_realloc64() */
11055
#define SQLITE_DESERIALIZE_READONLY    4 /* Database is read-only */
11056
11057
/*
11058
** Undo the hack that converts floating point types to integer for
11059
** builds on processors without floating point support.
11060
*/
11061
#ifdef SQLITE_OMIT_FLOATING_POINT
11062
# undef double
11063
#endif
11064
11065
#if defined(__wasi__)
11066
# undef SQLITE_WASI
11067
# define SQLITE_WASI 1
11068
# ifndef SQLITE_OMIT_LOAD_EXTENSION
11069
#  define SQLITE_OMIT_LOAD_EXTENSION
11070
# endif
11071
# ifndef SQLITE_THREADSAFE
11072
#  define SQLITE_THREADSAFE 0
11073
# endif
11074
#endif
11075
11076
#ifdef __cplusplus
11077
}  /* End of the 'extern "C"' block */
11078
#endif
11079
/* #endif for SQLITE3_H will be added by mksqlite3.tcl */
11080
11081
/******** Begin file sqlite3rtree.h *********/
11082
/*
11083
** 2010 August 30
11084
**
11085
** The author disclaims copyright to this source code.  In place of
11086
** a legal notice, here is a blessing:
11087
**
11088
**    May you do good and not evil.
11089
**    May you find forgiveness for yourself and forgive others.
11090
**    May you share freely, never taking more than you give.
11091
**
11092
*************************************************************************
11093
*/
11094
11095
#ifndef _SQLITE3RTREE_H_
11096
#define _SQLITE3RTREE_H_
11097
11098
11099
#ifdef __cplusplus
11100
extern "C" {
11101
#endif
11102
11103
typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
11104
typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
11105
11106
/* The double-precision datatype used by RTree depends on the
11107
** SQLITE_RTREE_INT_ONLY compile-time option.
11108
*/
11109
#ifdef SQLITE_RTREE_INT_ONLY
11110
  typedef sqlite3_int64 sqlite3_rtree_dbl;
11111
#else
11112
  typedef double sqlite3_rtree_dbl;
11113
#endif
11114
11115
/*
11116
** Register a geometry callback named zGeom that can be used as part of an
11117
** R-Tree geometry query as follows:
11118
**
11119
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
11120
*/
11121
SQLITE_API int sqlite3_rtree_geometry_callback(
11122
  sqlite3 *db,
11123
  const char *zGeom,
11124
  int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
11125
  void *pContext
11126
);
11127
11128
11129
/*
11130
** A pointer to a structure of the following type is passed as the first
11131
** argument to callbacks registered using rtree_geometry_callback().
11132
*/
11133
struct sqlite3_rtree_geometry {
11134
  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
11135
  int nParam;                     /* Size of array aParam[] */
11136
  sqlite3_rtree_dbl *aParam;      /* Parameters passed to SQL geom function */
11137
  void *pUser;                    /* Callback implementation user data */
11138
  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
11139
};
11140
11141
/*
11142
** Register a 2nd-generation geometry callback named zScore that can be
11143
** used as part of an R-Tree geometry query as follows:
11144
**
11145
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
11146
*/
11147
SQLITE_API int sqlite3_rtree_query_callback(
11148
  sqlite3 *db,
11149
  const char *zQueryFunc,
11150
  int (*xQueryFunc)(sqlite3_rtree_query_info*),
11151
  void *pContext,
11152
  void (*xDestructor)(void*)
11153
);
11154
11155
11156
/*
11157
** A pointer to a structure of the following type is passed as the
11158
** argument to scored geometry callback registered using
11159
** sqlite3_rtree_query_callback().
11160
**
11161
** Note that the first 5 fields of this structure are identical to
11162
** sqlite3_rtree_geometry.  This structure is a subclass of
11163
** sqlite3_rtree_geometry.
11164
*/
11165
struct sqlite3_rtree_query_info {
11166
  void *pContext;                   /* pContext from when function registered */
11167
  int nParam;                       /* Number of function parameters */
11168
  sqlite3_rtree_dbl *aParam;        /* value of function parameters */
11169
  void *pUser;                      /* callback can use this, if desired */
11170
  void (*xDelUser)(void*);          /* function to free pUser */
11171
  sqlite3_rtree_dbl *aCoord;        /* Coordinates of node or entry to check */
11172
  unsigned int *anQueue;            /* Number of pending entries in the queue */
11173
  int nCoord;                       /* Number of coordinates */
11174
  int iLevel;                       /* Level of current node or entry */
11175
  int mxLevel;                      /* The largest iLevel value in the tree */
11176
  sqlite3_int64 iRowid;             /* Rowid for current entry */
11177
  sqlite3_rtree_dbl rParentScore;   /* Score of parent node */
11178
  int eParentWithin;                /* Visibility of parent node */
11179
  int eWithin;                      /* OUT: Visibility */
11180
  sqlite3_rtree_dbl rScore;         /* OUT: Write the score here */
11181
  /* The following fields are only available in 3.8.11 and later */
11182
  sqlite3_value **apSqlParam;       /* Original SQL values of parameters */
11183
};
11184
11185
/*
11186
** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
11187
*/
11188
#define NOT_WITHIN       0   /* Object completely outside of query region */
11189
#define PARTLY_WITHIN    1   /* Object partially overlaps query region */
11190
#define FULLY_WITHIN     2   /* Object fully contained within query region */
11191
11192
11193
#ifdef __cplusplus
11194
}  /* end of the 'extern "C"' block */
11195
#endif
11196
11197
#endif  /* ifndef _SQLITE3RTREE_H_ */
11198
11199
/******** End of sqlite3rtree.h *********/
11200
/******** Begin file sqlite3session.h *********/
11201
11202
#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
11203
#define __SQLITESESSION_H_ 1
11204
11205
/*
11206
** Make sure we can call this stuff from C++.
11207
*/
11208
#ifdef __cplusplus
11209
extern "C" {
11210
#endif
11211
11212
11213
/*
11214
** CAPI3REF: Session Object Handle
11215
**
11216
** An instance of this object is a [session] that can be used to
11217
** record changes to a database.
11218
*/
11219
typedef struct sqlite3_session sqlite3_session;
11220
11221
/*
11222
** CAPI3REF: Changeset Iterator Handle
11223
**
11224
** An instance of this object acts as a cursor for iterating
11225
** over the elements of a [changeset] or [patchset].
11226
*/
11227
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
11228
11229
/*
11230
** CAPI3REF: Create A New Session Object
11231
** CONSTRUCTOR: sqlite3_session
11232
**
11233
** Create a new session object attached to database handle db. If successful,
11234
** a pointer to the new object is written to *ppSession and SQLITE_OK is
11235
** returned. If an error occurs, *ppSession is set to NULL and an SQLite
11236
** error code (e.g. SQLITE_NOMEM) is returned.
11237
**
11238
** It is possible to create multiple session objects attached to a single
11239
** database handle.
11240
**
11241
** Session objects created using this function should be deleted using the
11242
** [sqlite3session_delete()] function before the database handle that they
11243
** are attached to is itself closed. If the database handle is closed before
11244
** the session object is deleted, then the results of calling any session
11245
** module function, including [sqlite3session_delete()] on the session object
11246
** are undefined.
11247
**
11248
** Because the session module uses the [sqlite3_preupdate_hook()] API, it
11249
** is not possible for an application to register a pre-update hook on a
11250
** database handle that has one or more session objects attached. Nor is
11251
** it possible to create a session object attached to a database handle for
11252
** which a pre-update hook is already defined. The results of attempting
11253
** either of these things are undefined.
11254
**
11255
** The session object will be used to create changesets for tables in
11256
** database zDb, where zDb is either "main", or "temp", or the name of an
11257
** attached database. It is not an error if database zDb is not attached
11258
** to the database when the session object is created.
11259
*/
11260
SQLITE_API int sqlite3session_create(
11261
  sqlite3 *db,                    /* Database handle */
11262
  const char *zDb,                /* Name of db (e.g. "main") */
11263
  sqlite3_session **ppSession     /* OUT: New session object */
11264
);
11265
11266
/*
11267
** CAPI3REF: Delete A Session Object
11268
** DESTRUCTOR: sqlite3_session
11269
**
11270
** Delete a session object previously allocated using
11271
** [sqlite3session_create()]. Once a session object has been deleted, the
11272
** results of attempting to use pSession with any other session module
11273
** function are undefined.
11274
**
11275
** Session objects must be deleted before the database handle to which they
11276
** are attached is closed. Refer to the documentation for
11277
** [sqlite3session_create()] for details.
11278
*/
11279
SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
11280
11281
/*
11282
** CAPI3REF: Configure a Session Object
11283
** METHOD: sqlite3_session
11284
**
11285
** This method is used to configure a session object after it has been
11286
** created. At present the only valid values for the second parameter are
11287
** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID].
11288
**
11289
*/
11290
SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg);
11291
11292
/*
11293
** CAPI3REF: Options for sqlite3session_object_config
11294
**
11295
** The following values may passed as the the 2nd parameter to
11296
** sqlite3session_object_config().
11297
**
11298
** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd>
11299
**   This option is used to set, clear or query the flag that enables
11300
**   the [sqlite3session_changeset_size()] API. Because it imposes some
11301
**   computational overhead, this API is disabled by default. Argument
11302
**   pArg must point to a value of type (int). If the value is initially
11303
**   0, then the sqlite3session_changeset_size() API is disabled. If it
11304
**   is greater than 0, then the same API is enabled. Or, if the initial
11305
**   value is less than zero, no change is made. In all cases the (int)
11306
**   variable is set to 1 if the sqlite3session_changeset_size() API is
11307
**   enabled following the current call, or 0 otherwise.
11308
**
11309
**   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
11310
**   the first table has been attached to the session object.
11311
**
11312
** <dt>SQLITE_SESSION_OBJCONFIG_ROWID <dd>
11313
**   This option is used to set, clear or query the flag that enables
11314
**   collection of data for tables with no explicit PRIMARY KEY.
11315
**
11316
**   Normally, tables with no explicit PRIMARY KEY are simply ignored
11317
**   by the sessions module. However, if this flag is set, it behaves
11318
**   as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted
11319
**   as their leftmost columns.
11320
**
11321
**   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
11322
**   the first table has been attached to the session object.
11323
*/
11324
#define SQLITE_SESSION_OBJCONFIG_SIZE  1
11325
#define SQLITE_SESSION_OBJCONFIG_ROWID 2
11326
11327
/*
11328
** CAPI3REF: Enable Or Disable A Session Object
11329
** METHOD: sqlite3_session
11330
**
11331
** Enable or disable the recording of changes by a session object. When
11332
** enabled, a session object records changes made to the database. When
11333
** disabled - it does not. A newly created session object is enabled.
11334
** Refer to the documentation for [sqlite3session_changeset()] for further
11335
** details regarding how enabling and disabling a session object affects
11336
** the eventual changesets.
11337
**
11338
** Passing zero to this function disables the session. Passing a value
11339
** greater than zero enables it. Passing a value less than zero is a
11340
** no-op, and may be used to query the current state of the session.
11341
**
11342
** The return value indicates the final state of the session object: 0 if
11343
** the session is disabled, or 1 if it is enabled.
11344
*/
11345
SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
11346
11347
/*
11348
** CAPI3REF: Set Or Clear the Indirect Change Flag
11349
** METHOD: sqlite3_session
11350
**
11351
** Each change recorded by a session object is marked as either direct or
11352
** indirect. A change is marked as indirect if either:
11353
**
11354
** <ul>
11355
**   <li> The session object "indirect" flag is set when the change is
11356
**        made, or
11357
**   <li> The change is made by an SQL trigger or foreign key action
11358
**        instead of directly as a result of a users SQL statement.
11359
** </ul>
11360
**
11361
** If a single row is affected by more than one operation within a session,
11362
** then the change is considered indirect if all operations meet the criteria
11363
** for an indirect change above, or direct otherwise.
11364
**
11365
** This function is used to set, clear or query the session object indirect
11366
** flag.  If the second argument passed to this function is zero, then the
11367
** indirect flag is cleared. If it is greater than zero, the indirect flag
11368
** is set. Passing a value less than zero does not modify the current value
11369
** of the indirect flag, and may be used to query the current state of the
11370
** indirect flag for the specified session object.
11371
**
11372
** The return value indicates the final state of the indirect flag: 0 if
11373
** it is clear, or 1 if it is set.
11374
*/
11375
SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
11376
11377
/*
11378
** CAPI3REF: Attach A Table To A Session Object
11379
** METHOD: sqlite3_session
11380
**
11381
** If argument zTab is not NULL, then it is the name of a table to attach
11382
** to the session object passed as the first argument. All subsequent changes
11383
** made to the table while the session object is enabled will be recorded. See
11384
** documentation for [sqlite3session_changeset()] for further details.
11385
**
11386
** Or, if argument zTab is NULL, then changes are recorded for all tables
11387
** in the database. If additional tables are added to the database (by
11388
** executing "CREATE TABLE" statements) after this call is made, changes for
11389
** the new tables are also recorded.
11390
**
11391
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
11392
** defined as part of their CREATE TABLE statement. It does not matter if the
11393
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
11394
** KEY may consist of a single column, or may be a composite key.
11395
**
11396
** It is not an error if the named table does not exist in the database. Nor
11397
** is it an error if the named table does not have a PRIMARY KEY. However,
11398
** no changes will be recorded in either of these scenarios.
11399
**
11400
** Changes are not recorded for individual rows that have NULL values stored
11401
** in one or more of their PRIMARY KEY columns.
11402
**
11403
** SQLITE_OK is returned if the call completes without error. Or, if an error
11404
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
11405
**
11406
** <h3>Special sqlite_stat1 Handling</h3>
11407
**
11408
** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to
11409
** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
11410
**  <pre>
11411
**  &nbsp;     CREATE TABLE sqlite_stat1(tbl,idx,stat)
11412
**  </pre>
11413
**
11414
** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are
11415
** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes
11416
** are recorded for rows for which (idx IS NULL) is true. However, for such
11417
** rows a zero-length blob (SQL value X'') is stored in the changeset or
11418
** patchset instead of a NULL value. This allows such changesets to be
11419
** manipulated by legacy implementations of sqlite3changeset_invert(),
11420
** concat() and similar.
11421
**
11422
** The sqlite3changeset_apply() function automatically converts the
11423
** zero-length blob back to a NULL value when updating the sqlite_stat1
11424
** table. However, if the application calls sqlite3changeset_new(),
11425
** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset
11426
** iterator directly (including on a changeset iterator passed to a
11427
** conflict-handler callback) then the X'' value is returned. The application
11428
** must translate X'' to NULL itself if required.
11429
**
11430
** Legacy (older than 3.22.0) versions of the sessions module cannot capture
11431
** changes made to the sqlite_stat1 table. Legacy versions of the
11432
** sqlite3changeset_apply() function silently ignore any modifications to the
11433
** sqlite_stat1 table that are part of a changeset or patchset.
11434
*/
11435
SQLITE_API int sqlite3session_attach(
11436
  sqlite3_session *pSession,      /* Session object */
11437
  const char *zTab                /* Table name */
11438
);
11439
11440
/*
11441
** CAPI3REF: Set a table filter on a Session Object.
11442
** METHOD: sqlite3_session
11443
**
11444
** The second argument (xFilter) is the "filter callback". For changes to rows
11445
** in tables that are not attached to the Session object, the filter is called
11446
** to determine whether changes to the table's rows should be tracked or not.
11447
** If xFilter returns 0, changes are not tracked. Note that once a table is
11448
** attached, xFilter will not be called again.
11449
*/
11450
SQLITE_API void sqlite3session_table_filter(
11451
  sqlite3_session *pSession,      /* Session object */
11452
  int(*xFilter)(
11453
    void *pCtx,                   /* Copy of third arg to _filter_table() */
11454
    const char *zTab              /* Table name */
11455
  ),
11456
  void *pCtx                      /* First argument passed to xFilter */
11457
);
11458
11459
/*
11460
** CAPI3REF: Generate A Changeset From A Session Object
11461
** METHOD: sqlite3_session
11462
**
11463
** Obtain a changeset containing changes to the tables attached to the
11464
** session object passed as the first argument. If successful,
11465
** set *ppChangeset to point to a buffer containing the changeset
11466
** and *pnChangeset to the size of the changeset in bytes before returning
11467
** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
11468
** zero and return an SQLite error code.
11469
**
11470
** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
11471
** each representing a change to a single row of an attached table. An INSERT
11472
** change contains the values of each field of a new database row. A DELETE
11473
** contains the original values of each field of a deleted database row. An
11474
** UPDATE change contains the original values of each field of an updated
11475
** database row along with the updated values for each updated non-primary-key
11476
** column. It is not possible for an UPDATE change to represent a change that
11477
** modifies the values of primary key columns. If such a change is made, it
11478
** is represented in a changeset as a DELETE followed by an INSERT.
11479
**
11480
** Changes are not recorded for rows that have NULL values stored in one or
11481
** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
11482
** no corresponding change is present in the changesets returned by this
11483
** function. If an existing row with one or more NULL values stored in
11484
** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
11485
** only an INSERT is appears in the changeset. Similarly, if an existing row
11486
** with non-NULL PRIMARY KEY values is updated so that one or more of its
11487
** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
11488
** DELETE change only.
11489
**
11490
** The contents of a changeset may be traversed using an iterator created
11491
** using the [sqlite3changeset_start()] API. A changeset may be applied to
11492
** a database with a compatible schema using the [sqlite3changeset_apply()]
11493
** API.
11494
**
11495
** Within a changeset generated by this function, all changes related to a
11496
** single table are grouped together. In other words, when iterating through
11497
** a changeset or when applying a changeset to a database, all changes related
11498
** to a single table are processed before moving on to the next table. Tables
11499
** are sorted in the same order in which they were attached (or auto-attached)
11500
** to the sqlite3_session object. The order in which the changes related to
11501
** a single table are stored is undefined.
11502
**
11503
** Following a successful call to this function, it is the responsibility of
11504
** the caller to eventually free the buffer that *ppChangeset points to using
11505
** [sqlite3_free()].
11506
**
11507
** <h3>Changeset Generation</h3>
11508
**
11509
** Once a table has been attached to a session object, the session object
11510
** records the primary key values of all new rows inserted into the table.
11511
** It also records the original primary key and other column values of any
11512
** deleted or updated rows. For each unique primary key value, data is only
11513
** recorded once - the first time a row with said primary key is inserted,
11514
** updated or deleted in the lifetime of the session.
11515
**
11516
** There is one exception to the previous paragraph: when a row is inserted,
11517
** updated or deleted, if one or more of its primary key columns contain a
11518
** NULL value, no record of the change is made.
11519
**
11520
** The session object therefore accumulates two types of records - those
11521
** that consist of primary key values only (created when the user inserts
11522
** a new record) and those that consist of the primary key values and the
11523
** original values of other table columns (created when the users deletes
11524
** or updates a record).
11525
**
11526
** When this function is called, the requested changeset is created using
11527
** both the accumulated records and the current contents of the database
11528
** file. Specifically:
11529
**
11530
** <ul>
11531
**   <li> For each record generated by an insert, the database is queried
11532
**        for a row with a matching primary key. If one is found, an INSERT
11533
**        change is added to the changeset. If no such row is found, no change
11534
**        is added to the changeset.
11535
**
11536
**   <li> For each record generated by an update or delete, the database is
11537
**        queried for a row with a matching primary key. If such a row is
11538
**        found and one or more of the non-primary key fields have been
11539
**        modified from their original values, an UPDATE change is added to
11540
**        the changeset. Or, if no such row is found in the table, a DELETE
11541
**        change is added to the changeset. If there is a row with a matching
11542
**        primary key in the database, but all fields contain their original
11543
**        values, no change is added to the changeset.
11544
** </ul>
11545
**
11546
** This means, amongst other things, that if a row is inserted and then later
11547
** deleted while a session object is active, neither the insert nor the delete
11548
** will be present in the changeset. Or if a row is deleted and then later a
11549
** row with the same primary key values inserted while a session object is
11550
** active, the resulting changeset will contain an UPDATE change instead of
11551
** a DELETE and an INSERT.
11552
**
11553
** When a session object is disabled (see the [sqlite3session_enable()] API),
11554
** it does not accumulate records when rows are inserted, updated or deleted.
11555
** This may appear to have some counter-intuitive effects if a single row
11556
** is written to more than once during a session. For example, if a row
11557
** is inserted while a session object is enabled, then later deleted while
11558
** the same session object is disabled, no INSERT record will appear in the
11559
** changeset, even though the delete took place while the session was disabled.
11560
** Or, if one field of a row is updated while a session is enabled, and
11561
** then another field of the same row is updated while the session is disabled,
11562
** the resulting changeset will contain an UPDATE change that updates both
11563
** fields.
11564
*/
11565
SQLITE_API int sqlite3session_changeset(
11566
  sqlite3_session *pSession,      /* Session object */
11567
  int *pnChangeset,               /* OUT: Size of buffer at *ppChangeset */
11568
  void **ppChangeset              /* OUT: Buffer containing changeset */
11569
);
11570
11571
/*
11572
** CAPI3REF: Return An Upper-limit For The Size Of The Changeset
11573
** METHOD: sqlite3_session
11574
**
11575
** By default, this function always returns 0. For it to return
11576
** a useful result, the sqlite3_session object must have been configured
11577
** to enable this API using sqlite3session_object_config() with the
11578
** SQLITE_SESSION_OBJCONFIG_SIZE verb.
11579
**
11580
** When enabled, this function returns an upper limit, in bytes, for the size
11581
** of the changeset that might be produced if sqlite3session_changeset() were
11582
** called. The final changeset size might be equal to or smaller than the
11583
** size in bytes returned by this function.
11584
*/
11585
SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession);
11586
11587
/*
11588
** CAPI3REF: Load The Difference Between Tables Into A Session
11589
** METHOD: sqlite3_session
11590
**
11591
** If it is not already attached to the session object passed as the first
11592
** argument, this function attaches table zTbl in the same manner as the
11593
** [sqlite3session_attach()] function. If zTbl does not exist, or if it
11594
** does not have a primary key, this function is a no-op (but does not return
11595
** an error).
11596
**
11597
** Argument zFromDb must be the name of a database ("main", "temp" etc.)
11598
** attached to the same database handle as the session object that contains
11599
** a table compatible with the table attached to the session by this function.
11600
** A table is considered compatible if it:
11601
**
11602
** <ul>
11603
**   <li> Has the same name,
11604
**   <li> Has the same set of columns declared in the same order, and
11605
**   <li> Has the same PRIMARY KEY definition.
11606
** </ul>
11607
**
11608
** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
11609
** are compatible but do not have any PRIMARY KEY columns, it is not an error
11610
** but no changes are added to the session object. As with other session
11611
** APIs, tables without PRIMARY KEYs are simply ignored.
11612
**
11613
** This function adds a set of changes to the session object that could be
11614
** used to update the table in database zFrom (call this the "from-table")
11615
** so that its content is the same as the table attached to the session
11616
** object (call this the "to-table"). Specifically:
11617
**
11618
** <ul>
11619
**   <li> For each row (primary key) that exists in the to-table but not in
11620
**     the from-table, an INSERT record is added to the session object.
11621
**
11622
**   <li> For each row (primary key) that exists in the to-table but not in
11623
**     the from-table, a DELETE record is added to the session object.
11624
**
11625
**   <li> For each row (primary key) that exists in both tables, but features
11626
**     different non-PK values in each, an UPDATE record is added to the
11627
**     session.
11628
** </ul>
11629
**
11630
** To clarify, if this function is called and then a changeset constructed
11631
** using [sqlite3session_changeset()], then after applying that changeset to
11632
** database zFrom the contents of the two compatible tables would be
11633
** identical.
11634
**
11635
** Unless the call to this function is a no-op as described above, it is an
11636
** error if database zFrom does not exist or does not contain the required
11637
** compatible table.
11638
**
11639
** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite
11640
** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
11641
** may be set to point to a buffer containing an English language error
11642
** message. It is the responsibility of the caller to free this buffer using
11643
** sqlite3_free().
11644
*/
11645
SQLITE_API int sqlite3session_diff(
11646
  sqlite3_session *pSession,
11647
  const char *zFromDb,
11648
  const char *zTbl,
11649
  char **pzErrMsg
11650
);
11651
11652
11653
/*
11654
** CAPI3REF: Generate A Patchset From A Session Object
11655
** METHOD: sqlite3_session
11656
**
11657
** The differences between a patchset and a changeset are that:
11658
**
11659
** <ul>
11660
**   <li> DELETE records consist of the primary key fields only. The
11661
**        original values of other fields are omitted.
11662
**   <li> The original values of any modified fields are omitted from
11663
**        UPDATE records.
11664
** </ul>
11665
**
11666
** A patchset blob may be used with up to date versions of all
11667
** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
11668
** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
11669
** attempting to use a patchset blob with old versions of the
11670
** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
11671
**
11672
** Because the non-primary key "old.*" fields are omitted, no
11673
** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
11674
** is passed to the sqlite3changeset_apply() API. Other conflict types work
11675
** in the same way as for changesets.
11676
**
11677
** Changes within a patchset are ordered in the same way as for changesets
11678
** generated by the sqlite3session_changeset() function (i.e. all changes for
11679
** a single table are grouped together, tables appear in the order in which
11680
** they were attached to the session object).
11681
*/
11682
SQLITE_API int sqlite3session_patchset(
11683
  sqlite3_session *pSession,      /* Session object */
11684
  int *pnPatchset,                /* OUT: Size of buffer at *ppPatchset */
11685
  void **ppPatchset               /* OUT: Buffer containing patchset */
11686
);
11687
11688
/*
11689
** CAPI3REF: Test if a changeset has recorded any changes.
11690
**
11691
** Return non-zero if no changes to attached tables have been recorded by
11692
** the session object passed as the first argument. Otherwise, if one or
11693
** more changes have been recorded, return zero.
11694
**
11695
** Even if this function returns zero, it is possible that calling
11696
** [sqlite3session_changeset()] on the session handle may still return a
11697
** changeset that contains no changes. This can happen when a row in
11698
** an attached table is modified and then later on the original values
11699
** are restored. However, if this function returns non-zero, then it is
11700
** guaranteed that a call to sqlite3session_changeset() will return a
11701
** changeset containing zero changes.
11702
*/
11703
SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
11704
11705
/*
11706
** CAPI3REF: Query for the amount of heap memory used by a session object.
11707
**
11708
** This API returns the total amount of heap memory in bytes currently
11709
** used by the session object passed as the only argument.
11710
*/
11711
SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession);
11712
11713
/*
11714
** CAPI3REF: Create An Iterator To Traverse A Changeset
11715
** CONSTRUCTOR: sqlite3_changeset_iter
11716
**
11717
** Create an iterator used to iterate through the contents of a changeset.
11718
** If successful, *pp is set to point to the iterator handle and SQLITE_OK
11719
** is returned. Otherwise, if an error occurs, *pp is set to zero and an
11720
** SQLite error code is returned.
11721
**
11722
** The following functions can be used to advance and query a changeset
11723
** iterator created by this function:
11724
**
11725
** <ul>
11726
**   <li> [sqlite3changeset_next()]
11727
**   <li> [sqlite3changeset_op()]
11728
**   <li> [sqlite3changeset_new()]
11729
**   <li> [sqlite3changeset_old()]
11730
** </ul>
11731
**
11732
** It is the responsibility of the caller to eventually destroy the iterator
11733
** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
11734
** changeset (pChangeset) must remain valid until after the iterator is
11735
** destroyed.
11736
**
11737
** Assuming the changeset blob was created by one of the
11738
** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
11739
** [sqlite3changeset_invert()] functions, all changes within the changeset
11740
** that apply to a single table are grouped together. This means that when
11741
** an application iterates through a changeset using an iterator created by
11742
** this function, all changes that relate to a single table are visited
11743
** consecutively. There is no chance that the iterator will visit a change
11744
** the applies to table X, then one for table Y, and then later on visit
11745
** another change for table X.
11746
**
11747
** The behavior of sqlite3changeset_start_v2() and its streaming equivalent
11748
** may be modified by passing a combination of
11749
** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter.
11750
**
11751
** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b>
11752
** and therefore subject to change.
11753
*/
11754
SQLITE_API int sqlite3changeset_start(
11755
  sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
11756
  int nChangeset,                 /* Size of changeset blob in bytes */
11757
  void *pChangeset                /* Pointer to blob containing changeset */
11758
);
11759
SQLITE_API int sqlite3changeset_start_v2(
11760
  sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
11761
  int nChangeset,                 /* Size of changeset blob in bytes */
11762
  void *pChangeset,               /* Pointer to blob containing changeset */
11763
  int flags                       /* SESSION_CHANGESETSTART_* flags */
11764
);
11765
11766
/*
11767
** CAPI3REF: Flags for sqlite3changeset_start_v2
11768
**
11769
** The following flags may passed via the 4th parameter to
11770
** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]:
11771
**
11772
** <dt>SQLITE_CHANGESETSTART_INVERT <dd>
11773
**   Invert the changeset while iterating through it. This is equivalent to
11774
**   inverting a changeset using sqlite3changeset_invert() before applying it.
11775
**   It is an error to specify this flag with a patchset.
11776
*/
11777
#define SQLITE_CHANGESETSTART_INVERT        0x0002
11778
11779
11780
/*
11781
** CAPI3REF: Advance A Changeset Iterator
11782
** METHOD: sqlite3_changeset_iter
11783
**
11784
** This function may only be used with iterators created by the function
11785
** [sqlite3changeset_start()]. If it is called on an iterator passed to
11786
** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
11787
** is returned and the call has no effect.
11788
**
11789
** Immediately after an iterator is created by sqlite3changeset_start(), it
11790
** does not point to any change in the changeset. Assuming the changeset
11791
** is not empty, the first call to this function advances the iterator to
11792
** point to the first change in the changeset. Each subsequent call advances
11793
** the iterator to point to the next change in the changeset (if any). If
11794
** no error occurs and the iterator points to a valid change after a call
11795
** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
11796
** Otherwise, if all changes in the changeset have already been visited,
11797
** SQLITE_DONE is returned.
11798
**
11799
** If an error occurs, an SQLite error code is returned. Possible error
11800
** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
11801
** SQLITE_NOMEM.
11802
*/
11803
SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
11804
11805
/*
11806
** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
11807
** METHOD: sqlite3_changeset_iter
11808
**
11809
** The pIter argument passed to this function may either be an iterator
11810
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11811
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11812
** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
11813
** is not the case, this function returns [SQLITE_MISUSE].
11814
**
11815
** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three
11816
** outputs are set through these pointers:
11817
**
11818
** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
11819
** depending on the type of change that the iterator currently points to;
11820
**
11821
** *pnCol is set to the number of columns in the table affected by the change; and
11822
**
11823
** *pzTab is set to point to a nul-terminated utf-8 encoded string containing
11824
** the name of the table affected by the current change. The buffer remains
11825
** valid until either sqlite3changeset_next() is called on the iterator
11826
** or until the conflict-handler function returns.
11827
**
11828
** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change
11829
** is an indirect change, or false (0) otherwise. See the documentation for
11830
** [sqlite3session_indirect()] for a description of direct and indirect
11831
** changes.
11832
**
11833
** If no error occurs, SQLITE_OK is returned. If an error does occur, an
11834
** SQLite error code is returned. The values of the output variables may not
11835
** be trusted in this case.
11836
*/
11837
SQLITE_API int sqlite3changeset_op(
11838
  sqlite3_changeset_iter *pIter,  /* Iterator object */
11839
  const char **pzTab,             /* OUT: Pointer to table name */
11840
  int *pnCol,                     /* OUT: Number of columns in table */
11841
  int *pOp,                       /* OUT: SQLITE_INSERT, DELETE or UPDATE */
11842
  int *pbIndirect                 /* OUT: True for an 'indirect' change */
11843
);
11844
11845
/*
11846
** CAPI3REF: Obtain The Primary Key Definition Of A Table
11847
** METHOD: sqlite3_changeset_iter
11848
**
11849
** For each modified table, a changeset includes the following:
11850
**
11851
** <ul>
11852
**   <li> The number of columns in the table, and
11853
**   <li> Which of those columns make up the tables PRIMARY KEY.
11854
** </ul>
11855
**
11856
** This function is used to find which columns comprise the PRIMARY KEY of
11857
** the table modified by the change that iterator pIter currently points to.
11858
** If successful, *pabPK is set to point to an array of nCol entries, where
11859
** nCol is the number of columns in the table. Elements of *pabPK are set to
11860
** 0x01 if the corresponding column is part of the tables primary key, or
11861
** 0x00 if it is not.
11862
**
11863
** If argument pnCol is not NULL, then *pnCol is set to the number of columns
11864
** in the table.
11865
**
11866
** If this function is called when the iterator does not point to a valid
11867
** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
11868
** SQLITE_OK is returned and the output variables populated as described
11869
** above.
11870
*/
11871
SQLITE_API int sqlite3changeset_pk(
11872
  sqlite3_changeset_iter *pIter,  /* Iterator object */
11873
  unsigned char **pabPK,          /* OUT: Array of boolean - true for PK cols */
11874
  int *pnCol                      /* OUT: Number of entries in output array */
11875
);
11876
11877
/*
11878
** CAPI3REF: Obtain old.* Values From A Changeset Iterator
11879
** METHOD: sqlite3_changeset_iter
11880
**
11881
** The pIter argument passed to this function may either be an iterator
11882
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11883
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11884
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
11885
** Furthermore, it may only be called if the type of change that the iterator
11886
** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
11887
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
11888
**
11889
** Argument iVal must be greater than or equal to 0, and less than the number
11890
** of columns in the table affected by the current change. Otherwise,
11891
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11892
**
11893
** If successful, this function sets *ppValue to point to a protected
11894
** sqlite3_value object containing the iVal'th value from the vector of
11895
** original row values stored as part of the UPDATE or DELETE change and
11896
** returns SQLITE_OK. The name of the function comes from the fact that this
11897
** is similar to the "old.*" columns available to update or delete triggers.
11898
**
11899
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11900
** is returned and *ppValue is set to NULL.
11901
*/
11902
SQLITE_API int sqlite3changeset_old(
11903
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11904
  int iVal,                       /* Column number */
11905
  sqlite3_value **ppValue         /* OUT: Old value (or NULL pointer) */
11906
);
11907
11908
/*
11909
** CAPI3REF: Obtain new.* Values From A Changeset Iterator
11910
** METHOD: sqlite3_changeset_iter
11911
**
11912
** The pIter argument passed to this function may either be an iterator
11913
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11914
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11915
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
11916
** Furthermore, it may only be called if the type of change that the iterator
11917
** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
11918
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
11919
**
11920
** Argument iVal must be greater than or equal to 0, and less than the number
11921
** of columns in the table affected by the current change. Otherwise,
11922
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11923
**
11924
** If successful, this function sets *ppValue to point to a protected
11925
** sqlite3_value object containing the iVal'th value from the vector of
11926
** new row values stored as part of the UPDATE or INSERT change and
11927
** returns SQLITE_OK. If the change is an UPDATE and does not include
11928
** a new value for the requested column, *ppValue is set to NULL and
11929
** SQLITE_OK returned. The name of the function comes from the fact that
11930
** this is similar to the "new.*" columns available to update or delete
11931
** triggers.
11932
**
11933
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11934
** is returned and *ppValue is set to NULL.
11935
*/
11936
SQLITE_API int sqlite3changeset_new(
11937
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11938
  int iVal,                       /* Column number */
11939
  sqlite3_value **ppValue         /* OUT: New value (or NULL pointer) */
11940
);
11941
11942
/*
11943
** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
11944
** METHOD: sqlite3_changeset_iter
11945
**
11946
** This function should only be used with iterator objects passed to a
11947
** conflict-handler callback by [sqlite3changeset_apply()] with either
11948
** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
11949
** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
11950
** is set to NULL.
11951
**
11952
** Argument iVal must be greater than or equal to 0, and less than the number
11953
** of columns in the table affected by the current change. Otherwise,
11954
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11955
**
11956
** If successful, this function sets *ppValue to point to a protected
11957
** sqlite3_value object containing the iVal'th value from the
11958
** "conflicting row" associated with the current conflict-handler callback
11959
** and returns SQLITE_OK.
11960
**
11961
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11962
** is returned and *ppValue is set to NULL.
11963
*/
11964
SQLITE_API int sqlite3changeset_conflict(
11965
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11966
  int iVal,                       /* Column number */
11967
  sqlite3_value **ppValue         /* OUT: Value from conflicting row */
11968
);
11969
11970
/*
11971
** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
11972
** METHOD: sqlite3_changeset_iter
11973
**
11974
** This function may only be called with an iterator passed to an
11975
** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
11976
** it sets the output variable to the total number of known foreign key
11977
** violations in the destination database and returns SQLITE_OK.
11978
**
11979
** In all other cases this function returns SQLITE_MISUSE.
11980
*/
11981
SQLITE_API int sqlite3changeset_fk_conflicts(
11982
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11983
  int *pnOut                      /* OUT: Number of FK violations */
11984
);
11985
11986
11987
/*
11988
** CAPI3REF: Finalize A Changeset Iterator
11989
** METHOD: sqlite3_changeset_iter
11990
**
11991
** This function is used to finalize an iterator allocated with
11992
** [sqlite3changeset_start()].
11993
**
11994
** This function should only be called on iterators created using the
11995
** [sqlite3changeset_start()] function. If an application calls this
11996
** function with an iterator passed to a conflict-handler by
11997
** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
11998
** call has no effect.
11999
**
12000
** If an error was encountered within a call to an sqlite3changeset_xxx()
12001
** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
12002
** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
12003
** to that error is returned by this function. Otherwise, SQLITE_OK is
12004
** returned. This is to allow the following pattern (pseudo-code):
12005
**
12006
** <pre>
12007
**   sqlite3changeset_start();
12008
**   while( SQLITE_ROW==sqlite3changeset_next() ){
12009
**     // Do something with change.
12010
**   }
12011
**   rc = sqlite3changeset_finalize();
12012
**   if( rc!=SQLITE_OK ){
12013
**     // An error has occurred
12014
**   }
12015
** </pre>
12016
*/
12017
SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
12018
12019
/*
12020
** CAPI3REF: Invert A Changeset
12021
**
12022
** This function is used to "invert" a changeset object. Applying an inverted
12023
** changeset to a database reverses the effects of applying the uninverted
12024
** changeset. Specifically:
12025
**
12026
** <ul>
12027
**   <li> Each DELETE change is changed to an INSERT, and
12028
**   <li> Each INSERT change is changed to a DELETE, and
12029
**   <li> For each UPDATE change, the old.* and new.* values are exchanged.
12030
** </ul>
12031
**
12032
** This function does not change the order in which changes appear within
12033
** the changeset. It merely reverses the sense of each individual change.
12034
**
12035
** If successful, a pointer to a buffer containing the inverted changeset
12036
** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
12037
** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
12038
** zeroed and an SQLite error code returned.
12039
**
12040
** It is the responsibility of the caller to eventually call sqlite3_free()
12041
** on the *ppOut pointer to free the buffer allocation following a successful
12042
** call to this function.
12043
**
12044
** WARNING/TODO: This function currently assumes that the input is a valid
12045
** changeset. If it is not, the results are undefined.
12046
*/
12047
SQLITE_API int sqlite3changeset_invert(
12048
  int nIn, const void *pIn,       /* Input changeset */
12049
  int *pnOut, void **ppOut        /* OUT: Inverse of input */
12050
);
12051
12052
/*
12053
** CAPI3REF: Concatenate Two Changeset Objects
12054
**
12055
** This function is used to concatenate two changesets, A and B, into a
12056
** single changeset. The result is a changeset equivalent to applying
12057
** changeset A followed by changeset B.
12058
**
12059
** This function combines the two input changesets using an
12060
** sqlite3_changegroup object. Calling it produces similar results as the
12061
** following code fragment:
12062
**
12063
** <pre>
12064
**   sqlite3_changegroup *pGrp;
12065
**   rc = sqlite3_changegroup_new(&pGrp);
12066
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
12067
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
12068
**   if( rc==SQLITE_OK ){
12069
**     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
12070
**   }else{
12071
**     *ppOut = 0;
12072
**     *pnOut = 0;
12073
**   }
12074
** </pre>
12075
**
12076
** Refer to the sqlite3_changegroup documentation below for details.
12077
*/
12078
SQLITE_API int sqlite3changeset_concat(
12079
  int nA,                         /* Number of bytes in buffer pA */
12080
  void *pA,                       /* Pointer to buffer containing changeset A */
12081
  int nB,                         /* Number of bytes in buffer pB */
12082
  void *pB,                       /* Pointer to buffer containing changeset B */
12083
  int *pnOut,                     /* OUT: Number of bytes in output changeset */
12084
  void **ppOut                    /* OUT: Buffer containing output changeset */
12085
);
12086
12087
/*
12088
** CAPI3REF: Changegroup Handle
12089
**
12090
** A changegroup is an object used to combine two or more
12091
** [changesets] or [patchsets]
12092
*/
12093
typedef struct sqlite3_changegroup sqlite3_changegroup;
12094
12095
/*
12096
** CAPI3REF: Create A New Changegroup Object
12097
** CONSTRUCTOR: sqlite3_changegroup
12098
**
12099
** An sqlite3_changegroup object is used to combine two or more changesets
12100
** (or patchsets) into a single changeset (or patchset). A single changegroup
12101
** object may combine changesets or patchsets, but not both. The output is
12102
** always in the same format as the input.
12103
**
12104
** If successful, this function returns SQLITE_OK and populates (*pp) with
12105
** a pointer to a new sqlite3_changegroup object before returning. The caller
12106
** should eventually free the returned object using a call to
12107
** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
12108
** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
12109
**
12110
** The usual usage pattern for an sqlite3_changegroup object is as follows:
12111
**
12112
** <ul>
12113
**   <li> It is created using a call to sqlite3changegroup_new().
12114
**
12115
**   <li> Zero or more changesets (or patchsets) are added to the object
12116
**        by calling sqlite3changegroup_add().
12117
**
12118
**   <li> The result of combining all input changesets together is obtained
12119
**        by the application via a call to sqlite3changegroup_output().
12120
**
12121
**   <li> The object is deleted using a call to sqlite3changegroup_delete().
12122
** </ul>
12123
**
12124
** Any number of calls to add() and output() may be made between the calls to
12125
** new() and delete(), and in any order.
12126
**
12127
** As well as the regular sqlite3changegroup_add() and
12128
** sqlite3changegroup_output() functions, also available are the streaming
12129
** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
12130
*/
12131
SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
12132
12133
/*
12134
** CAPI3REF: Add a Schema to a Changegroup
12135
** METHOD: sqlite3_changegroup_schema
12136
**
12137
** This method may be used to optionally enforce the rule that the changesets
12138
** added to the changegroup handle must match the schema of database zDb
12139
** ("main", "temp", or the name of an attached database). If
12140
** sqlite3changegroup_add() is called to add a changeset that is not compatible
12141
** with the configured schema, SQLITE_SCHEMA is returned and the changegroup
12142
** object is left in an undefined state.
12143
**
12144
** A changeset schema is considered compatible with the database schema in
12145
** the same way as for sqlite3changeset_apply(). Specifically, for each
12146
** table in the changeset, there exists a database table with:
12147
**
12148
** <ul>
12149
**   <li> The name identified by the changeset, and
12150
**   <li> at least as many columns as recorded in the changeset, and
12151
**   <li> the primary key columns in the same position as recorded in
12152
**        the changeset.
12153
** </ul>
12154
**
12155
** The output of the changegroup object always has the same schema as the
12156
** database nominated using this function. In cases where changesets passed
12157
** to sqlite3changegroup_add() have fewer columns than the corresponding table
12158
** in the database schema, these are filled in using the default column
12159
** values from the database schema. This makes it possible to combined
12160
** changesets that have different numbers of columns for a single table
12161
** within a changegroup, provided that they are otherwise compatible.
12162
*/
12163
SQLITE_API int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb);
12164
12165
/*
12166
** CAPI3REF: Add A Changeset To A Changegroup
12167
** METHOD: sqlite3_changegroup
12168
**
12169
** Add all changes within the changeset (or patchset) in buffer pData (size
12170
** nData bytes) to the changegroup.
12171
**
12172
** If the buffer contains a patchset, then all prior calls to this function
12173
** on the same changegroup object must also have specified patchsets. Or, if
12174
** the buffer contains a changeset, so must have the earlier calls to this
12175
** function. Otherwise, SQLITE_ERROR is returned and no changes are added
12176
** to the changegroup.
12177
**
12178
** Rows within the changeset and changegroup are identified by the values in
12179
** their PRIMARY KEY columns. A change in the changeset is considered to
12180
** apply to the same row as a change already present in the changegroup if
12181
** the two rows have the same primary key.
12182
**
12183
** Changes to rows that do not already appear in the changegroup are
12184
** simply copied into it. Or, if both the new changeset and the changegroup
12185
** contain changes that apply to a single row, the final contents of the
12186
** changegroup depends on the type of each change, as follows:
12187
**
12188
** <table border=1 style="margin-left:8ex;margin-right:8ex">
12189
**   <tr><th style="white-space:pre">Existing Change  </th>
12190
**       <th style="white-space:pre">New Change       </th>
12191
**       <th>Output Change
12192
**   <tr><td>INSERT <td>INSERT <td>
12193
**       The new change is ignored. This case does not occur if the new
12194
**       changeset was recorded immediately after the changesets already
12195
**       added to the changegroup.
12196
**   <tr><td>INSERT <td>UPDATE <td>
12197
**       The INSERT change remains in the changegroup. The values in the
12198
**       INSERT change are modified as if the row was inserted by the
12199
**       existing change and then updated according to the new change.
12200
**   <tr><td>INSERT <td>DELETE <td>
12201
**       The existing INSERT is removed from the changegroup. The DELETE is
12202
**       not added.
12203
**   <tr><td>UPDATE <td>INSERT <td>
12204
**       The new change is ignored. This case does not occur if the new
12205
**       changeset was recorded immediately after the changesets already
12206
**       added to the changegroup.
12207
**   <tr><td>UPDATE <td>UPDATE <td>
12208
**       The existing UPDATE remains within the changegroup. It is amended
12209
**       so that the accompanying values are as if the row was updated once
12210
**       by the existing change and then again by the new change.
12211
**   <tr><td>UPDATE <td>DELETE <td>
12212
**       The existing UPDATE is replaced by the new DELETE within the
12213
**       changegroup.
12214
**   <tr><td>DELETE <td>INSERT <td>
12215
**       If one or more of the column values in the row inserted by the
12216
**       new change differ from those in the row deleted by the existing
12217
**       change, the existing DELETE is replaced by an UPDATE within the
12218
**       changegroup. Otherwise, if the inserted row is exactly the same
12219
**       as the deleted row, the existing DELETE is simply discarded.
12220
**   <tr><td>DELETE <td>UPDATE <td>
12221
**       The new change is ignored. This case does not occur if the new
12222
**       changeset was recorded immediately after the changesets already
12223
**       added to the changegroup.
12224
**   <tr><td>DELETE <td>DELETE <td>
12225
**       The new change is ignored. This case does not occur if the new
12226
**       changeset was recorded immediately after the changesets already
12227
**       added to the changegroup.
12228
** </table>
12229
**
12230
** If the new changeset contains changes to a table that is already present
12231
** in the changegroup, then the number of columns and the position of the
12232
** primary key columns for the table must be consistent. If this is not the
12233
** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup
12234
** object has been configured with a database schema using the
12235
** sqlite3changegroup_schema() API, then it is possible to combine changesets
12236
** with different numbers of columns for a single table, provided that
12237
** they are otherwise compatible.
12238
**
12239
** If the input changeset appears to be corrupt and the corruption is
12240
** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition
12241
** occurs during processing, this function returns SQLITE_NOMEM.
12242
**
12243
** In all cases, if an error occurs the state of the final contents of the
12244
** changegroup is undefined. If no error occurs, SQLITE_OK is returned.
12245
*/
12246
SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
12247
12248
/*
12249
** CAPI3REF: Add A Single Change To A Changegroup
12250
** METHOD: sqlite3_changegroup
12251
**
12252
** This function adds the single change currently indicated by the iterator
12253
** passed as the second argument to the changegroup object. The rules for
12254
** adding the change are just as described for [sqlite3changegroup_add()].
12255
**
12256
** If the change is successfully added to the changegroup, SQLITE_OK is
12257
** returned. Otherwise, an SQLite error code is returned.
12258
**
12259
** The iterator must point to a valid entry when this function is called.
12260
** If it does not, SQLITE_ERROR is returned and no change is added to the
12261
** changegroup. Additionally, the iterator must not have been opened with
12262
** the SQLITE_CHANGESETAPPLY_INVERT flag. In this case SQLITE_ERROR is also
12263
** returned.
12264
*/
12265
SQLITE_API int sqlite3changegroup_add_change(
12266
  sqlite3_changegroup*,
12267
  sqlite3_changeset_iter*
12268
);
12269
12270
12271
12272
/*
12273
** CAPI3REF: Obtain A Composite Changeset From A Changegroup
12274
** METHOD: sqlite3_changegroup
12275
**
12276
** Obtain a buffer containing a changeset (or patchset) representing the
12277
** current contents of the changegroup. If the inputs to the changegroup
12278
** were themselves changesets, the output is a changeset. Or, if the
12279
** inputs were patchsets, the output is also a patchset.
12280
**
12281
** As with the output of the sqlite3session_changeset() and
12282
** sqlite3session_patchset() functions, all changes related to a single
12283
** table are grouped together in the output of this function. Tables appear
12284
** in the same order as for the very first changeset added to the changegroup.
12285
** If the second or subsequent changesets added to the changegroup contain
12286
** changes for tables that do not appear in the first changeset, they are
12287
** appended onto the end of the output changeset, again in the order in
12288
** which they are first encountered.
12289
**
12290
** If an error occurs, an SQLite error code is returned and the output
12291
** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
12292
** is returned and the output variables are set to the size of and a
12293
** pointer to the output buffer, respectively. In this case it is the
12294
** responsibility of the caller to eventually free the buffer using a
12295
** call to sqlite3_free().
12296
*/
12297
SQLITE_API int sqlite3changegroup_output(
12298
  sqlite3_changegroup*,
12299
  int *pnData,                    /* OUT: Size of output buffer in bytes */
12300
  void **ppData                   /* OUT: Pointer to output buffer */
12301
);
12302
12303
/*
12304
** CAPI3REF: Delete A Changegroup Object
12305
** DESTRUCTOR: sqlite3_changegroup
12306
*/
12307
SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
12308
12309
/*
12310
** CAPI3REF: Apply A Changeset To A Database
12311
**
12312
** Apply a changeset or patchset to a database. These functions attempt to
12313
** update the "main" database attached to handle db with the changes found in
12314
** the changeset passed via the second and third arguments.
12315
**
12316
** The fourth argument (xFilter) passed to these functions is the "filter
12317
** callback". If it is not NULL, then for each table affected by at least one
12318
** change in the changeset, the filter callback is invoked with
12319
** the table name as the second argument, and a copy of the context pointer
12320
** passed as the sixth argument as the first. If the "filter callback"
12321
** returns zero, then no attempt is made to apply any changes to the table.
12322
** Otherwise, if the return value is non-zero or the xFilter argument to
12323
** is NULL, all changes related to the table are attempted.
12324
**
12325
** For each table that is not excluded by the filter callback, this function
12326
** tests that the target database contains a compatible table. A table is
12327
** considered compatible if all of the following are true:
12328
**
12329
** <ul>
12330
**   <li> The table has the same name as the name recorded in the
12331
**        changeset, and
12332
**   <li> The table has at least as many columns as recorded in the
12333
**        changeset, and
12334
**   <li> The table has primary key columns in the same position as
12335
**        recorded in the changeset.
12336
** </ul>
12337
**
12338
** If there is no compatible table, it is not an error, but none of the
12339
** changes associated with the table are applied. A warning message is issued
12340
** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
12341
** one such warning is issued for each table in the changeset.
12342
**
12343
** For each change for which there is a compatible table, an attempt is made
12344
** to modify the table contents according to the UPDATE, INSERT or DELETE
12345
** change. If a change cannot be applied cleanly, the conflict handler
12346
** function passed as the fifth argument to sqlite3changeset_apply() may be
12347
** invoked. A description of exactly when the conflict handler is invoked for
12348
** each type of change is below.
12349
**
12350
** Unlike the xFilter argument, xConflict may not be passed NULL. The results
12351
** of passing anything other than a valid function pointer as the xConflict
12352
** argument are undefined.
12353
**
12354
** Each time the conflict handler function is invoked, it must return one
12355
** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
12356
** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
12357
** if the second argument passed to the conflict handler is either
12358
** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
12359
** returns an illegal value, any changes already made are rolled back and
12360
** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
12361
** actions are taken by sqlite3changeset_apply() depending on the value
12362
** returned by each invocation of the conflict-handler function. Refer to
12363
** the documentation for the three
12364
** [SQLITE_CHANGESET_OMIT|available return values] for details.
12365
**
12366
** <dl>
12367
** <dt>DELETE Changes<dd>
12368
**   For each DELETE change, the function checks if the target database
12369
**   contains a row with the same primary key value (or values) as the
12370
**   original row values stored in the changeset. If it does, and the values
12371
**   stored in all non-primary key columns also match the values stored in
12372
**   the changeset the row is deleted from the target database.
12373
**
12374
**   If a row with matching primary key values is found, but one or more of
12375
**   the non-primary key fields contains a value different from the original
12376
**   row value stored in the changeset, the conflict-handler function is
12377
**   invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
12378
**   database table has more columns than are recorded in the changeset,
12379
**   only the values of those non-primary key fields are compared against
12380
**   the current database contents - any trailing database table columns
12381
**   are ignored.
12382
**
12383
**   If no row with matching primary key values is found in the database,
12384
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
12385
**   passed as the second argument.
12386
**
12387
**   If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
12388
**   (which can only happen if a foreign key constraint is violated), the
12389
**   conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
12390
**   passed as the second argument. This includes the case where the DELETE
12391
**   operation is attempted because an earlier call to the conflict handler
12392
**   function returned [SQLITE_CHANGESET_REPLACE].
12393
**
12394
** <dt>INSERT Changes<dd>
12395
**   For each INSERT change, an attempt is made to insert the new row into
12396
**   the database. If the changeset row contains fewer fields than the
12397
**   database table, the trailing fields are populated with their default
12398
**   values.
12399
**
12400
**   If the attempt to insert the row fails because the database already
12401
**   contains a row with the same primary key values, the conflict handler
12402
**   function is invoked with the second argument set to
12403
**   [SQLITE_CHANGESET_CONFLICT].
12404
**
12405
**   If the attempt to insert the row fails because of some other constraint
12406
**   violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
12407
**   invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
12408
**   This includes the case where the INSERT operation is re-attempted because
12409
**   an earlier call to the conflict handler function returned
12410
**   [SQLITE_CHANGESET_REPLACE].
12411
**
12412
** <dt>UPDATE Changes<dd>
12413
**   For each UPDATE change, the function checks if the target database
12414
**   contains a row with the same primary key value (or values) as the
12415
**   original row values stored in the changeset. If it does, and the values
12416
**   stored in all modified non-primary key columns also match the values
12417
**   stored in the changeset the row is updated within the target database.
12418
**
12419
**   If a row with matching primary key values is found, but one or more of
12420
**   the modified non-primary key fields contains a value different from an
12421
**   original row value stored in the changeset, the conflict-handler function
12422
**   is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
12423
**   UPDATE changes only contain values for non-primary key fields that are
12424
**   to be modified, only those fields need to match the original values to
12425
**   avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
12426
**
12427
**   If no row with matching primary key values is found in the database,
12428
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
12429
**   passed as the second argument.
12430
**
12431
**   If the UPDATE operation is attempted, but SQLite returns
12432
**   SQLITE_CONSTRAINT, the conflict-handler function is invoked with
12433
**   [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
12434
**   This includes the case where the UPDATE operation is attempted after
12435
**   an earlier call to the conflict handler function returned
12436
**   [SQLITE_CHANGESET_REPLACE].
12437
** </dl>
12438
**
12439
** It is safe to execute SQL statements, including those that write to the
12440
** table that the callback related to, from within the xConflict callback.
12441
** This can be used to further customize the application's conflict
12442
** resolution strategy.
12443
**
12444
** All changes made by these functions are enclosed in a savepoint transaction.
12445
** If any other error (aside from a constraint failure when attempting to
12446
** write to the target database) occurs, then the savepoint transaction is
12447
** rolled back, restoring the target database to its original state, and an
12448
** SQLite error code returned.
12449
**
12450
** If the output parameters (ppRebase) and (pnRebase) are non-NULL and
12451
** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2()
12452
** may set (*ppRebase) to point to a "rebase" that may be used with the
12453
** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase)
12454
** is set to the size of the buffer in bytes. It is the responsibility of the
12455
** caller to eventually free any such buffer using sqlite3_free(). The buffer
12456
** is only allocated and populated if one or more conflicts were encountered
12457
** while applying the patchset. See comments surrounding the sqlite3_rebaser
12458
** APIs for further details.
12459
**
12460
** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent
12461
** may be modified by passing a combination of
12462
** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter.
12463
**
12464
** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b>
12465
** and therefore subject to change.
12466
*/
12467
SQLITE_API int sqlite3changeset_apply(
12468
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12469
  int nChangeset,                 /* Size of changeset in bytes */
12470
  void *pChangeset,               /* Changeset blob */
12471
  int(*xFilter)(
12472
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12473
    const char *zTab              /* Table name */
12474
  ),
12475
  int(*xConflict)(
12476
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12477
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12478
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12479
  ),
12480
  void *pCtx                      /* First argument passed to xConflict */
12481
);
12482
SQLITE_API int sqlite3changeset_apply_v2(
12483
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12484
  int nChangeset,                 /* Size of changeset in bytes */
12485
  void *pChangeset,               /* Changeset blob */
12486
  int(*xFilter)(
12487
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12488
    const char *zTab              /* Table name */
12489
  ),
12490
  int(*xConflict)(
12491
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12492
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12493
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12494
  ),
12495
  void *pCtx,                     /* First argument passed to xConflict */
12496
  void **ppRebase, int *pnRebase, /* OUT: Rebase data */
12497
  int flags                       /* SESSION_CHANGESETAPPLY_* flags */
12498
);
12499
12500
/*
12501
** CAPI3REF: Flags for sqlite3changeset_apply_v2
12502
**
12503
** The following flags may passed via the 9th parameter to
12504
** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]:
12505
**
12506
** <dl>
12507
** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd>
12508
**   Usually, the sessions module encloses all operations performed by
12509
**   a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The
12510
**   SAVEPOINT is committed if the changeset or patchset is successfully
12511
**   applied, or rolled back if an error occurs. Specifying this flag
12512
**   causes the sessions module to omit this savepoint. In this case, if the
12513
**   caller has an open transaction or savepoint when apply_v2() is called,
12514
**   it may revert the partially applied changeset by rolling it back.
12515
**
12516
** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
12517
**   Invert the changeset before applying it. This is equivalent to inverting
12518
**   a changeset using sqlite3changeset_invert() before applying it. It is
12519
**   an error to specify this flag with a patchset.
12520
**
12521
** <dt>SQLITE_CHANGESETAPPLY_IGNORENOOP <dd>
12522
**   Do not invoke the conflict handler callback for any changes that
12523
**   would not actually modify the database even if they were applied.
12524
**   Specifically, this means that the conflict handler is not invoked
12525
**   for:
12526
**    <ul>
12527
**    <li>a delete change if the row being deleted cannot be found,
12528
**    <li>an update change if the modified fields are already set to
12529
**        their new values in the conflicting row, or
12530
**    <li>an insert change if all fields of the conflicting row match
12531
**        the row being inserted.
12532
**    </ul>
12533
**
12534
** <dt>SQLITE_CHANGESETAPPLY_FKNOACTION <dd>
12535
**   If this flag it set, then all foreign key constraints in the target
12536
**   database behave as if they were declared with "ON UPDATE NO ACTION ON
12537
**   DELETE NO ACTION", even if they are actually CASCADE, RESTRICT, SET NULL
12538
**   or SET DEFAULT.
12539
*/
12540
#define SQLITE_CHANGESETAPPLY_NOSAVEPOINT   0x0001
12541
#define SQLITE_CHANGESETAPPLY_INVERT        0x0002
12542
#define SQLITE_CHANGESETAPPLY_IGNORENOOP    0x0004
12543
#define SQLITE_CHANGESETAPPLY_FKNOACTION    0x0008
12544
12545
/*
12546
** CAPI3REF: Constants Passed To The Conflict Handler
12547
**
12548
** Values that may be passed as the second argument to a conflict-handler.
12549
**
12550
** <dl>
12551
** <dt>SQLITE_CHANGESET_DATA<dd>
12552
**   The conflict handler is invoked with CHANGESET_DATA as the second argument
12553
**   when processing a DELETE or UPDATE change if a row with the required
12554
**   PRIMARY KEY fields is present in the database, but one or more other
12555
**   (non primary-key) fields modified by the update do not contain the
12556
**   expected "before" values.
12557
**
12558
**   The conflicting row, in this case, is the database row with the matching
12559
**   primary key.
12560
**
12561
** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
12562
**   The conflict handler is invoked with CHANGESET_NOTFOUND as the second
12563
**   argument when processing a DELETE or UPDATE change if a row with the
12564
**   required PRIMARY KEY fields is not present in the database.
12565
**
12566
**   There is no conflicting row in this case. The results of invoking the
12567
**   sqlite3changeset_conflict() API are undefined.
12568
**
12569
** <dt>SQLITE_CHANGESET_CONFLICT<dd>
12570
**   CHANGESET_CONFLICT is passed as the second argument to the conflict
12571
**   handler while processing an INSERT change if the operation would result
12572
**   in duplicate primary key values.
12573
**
12574
**   The conflicting row in this case is the database row with the matching
12575
**   primary key.
12576
**
12577
** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
12578
**   If foreign key handling is enabled, and applying a changeset leaves the
12579
**   database in a state containing foreign key violations, the conflict
12580
**   handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
12581
**   exactly once before the changeset is committed. If the conflict handler
12582
**   returns CHANGESET_OMIT, the changes, including those that caused the
12583
**   foreign key constraint violation, are committed. Or, if it returns
12584
**   CHANGESET_ABORT, the changeset is rolled back.
12585
**
12586
**   No current or conflicting row information is provided. The only function
12587
**   it is possible to call on the supplied sqlite3_changeset_iter handle
12588
**   is sqlite3changeset_fk_conflicts().
12589
**
12590
** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
12591
**   If any other constraint violation occurs while applying a change (i.e.
12592
**   a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
12593
**   invoked with CHANGESET_CONSTRAINT as the second argument.
12594
**
12595
**   There is no conflicting row in this case. The results of invoking the
12596
**   sqlite3changeset_conflict() API are undefined.
12597
**
12598
** </dl>
12599
*/
12600
#define SQLITE_CHANGESET_DATA        1
12601
#define SQLITE_CHANGESET_NOTFOUND    2
12602
#define SQLITE_CHANGESET_CONFLICT    3
12603
#define SQLITE_CHANGESET_CONSTRAINT  4
12604
#define SQLITE_CHANGESET_FOREIGN_KEY 5
12605
12606
/*
12607
** CAPI3REF: Constants Returned By The Conflict Handler
12608
**
12609
** A conflict handler callback must return one of the following three values.
12610
**
12611
** <dl>
12612
** <dt>SQLITE_CHANGESET_OMIT<dd>
12613
**   If a conflict handler returns this value no special action is taken. The
12614
**   change that caused the conflict is not applied. The session module
12615
**   continues to the next change in the changeset.
12616
**
12617
** <dt>SQLITE_CHANGESET_REPLACE<dd>
12618
**   This value may only be returned if the second argument to the conflict
12619
**   handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
12620
**   is not the case, any changes applied so far are rolled back and the
12621
**   call to sqlite3changeset_apply() returns SQLITE_MISUSE.
12622
**
12623
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
12624
**   handler, then the conflicting row is either updated or deleted, depending
12625
**   on the type of change.
12626
**
12627
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
12628
**   handler, then the conflicting row is removed from the database and a
12629
**   second attempt to apply the change is made. If this second attempt fails,
12630
**   the original row is restored to the database before continuing.
12631
**
12632
** <dt>SQLITE_CHANGESET_ABORT<dd>
12633
**   If this value is returned, any changes applied so far are rolled back
12634
**   and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
12635
** </dl>
12636
*/
12637
#define SQLITE_CHANGESET_OMIT       0
12638
#define SQLITE_CHANGESET_REPLACE    1
12639
#define SQLITE_CHANGESET_ABORT      2
12640
12641
/*
12642
** CAPI3REF: Rebasing changesets
12643
** EXPERIMENTAL
12644
**
12645
** Suppose there is a site hosting a database in state S0. And that
12646
** modifications are made that move that database to state S1 and a
12647
** changeset recorded (the "local" changeset). Then, a changeset based
12648
** on S0 is received from another site (the "remote" changeset) and
12649
** applied to the database. The database is then in state
12650
** (S1+"remote"), where the exact state depends on any conflict
12651
** resolution decisions (OMIT or REPLACE) made while applying "remote".
12652
** Rebasing a changeset is to update it to take those conflict
12653
** resolution decisions into account, so that the same conflicts
12654
** do not have to be resolved elsewhere in the network.
12655
**
12656
** For example, if both the local and remote changesets contain an
12657
** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)":
12658
**
12659
**   local:  INSERT INTO t1 VALUES(1, 'v1');
12660
**   remote: INSERT INTO t1 VALUES(1, 'v2');
12661
**
12662
** and the conflict resolution is REPLACE, then the INSERT change is
12663
** removed from the local changeset (it was overridden). Or, if the
12664
** conflict resolution was "OMIT", then the local changeset is modified
12665
** to instead contain:
12666
**
12667
**           UPDATE t1 SET b = 'v2' WHERE a=1;
12668
**
12669
** Changes within the local changeset are rebased as follows:
12670
**
12671
** <dl>
12672
** <dt>Local INSERT<dd>
12673
**   This may only conflict with a remote INSERT. If the conflict
12674
**   resolution was OMIT, then add an UPDATE change to the rebased
12675
**   changeset. Or, if the conflict resolution was REPLACE, add
12676
**   nothing to the rebased changeset.
12677
**
12678
** <dt>Local DELETE<dd>
12679
**   This may conflict with a remote UPDATE or DELETE. In both cases the
12680
**   only possible resolution is OMIT. If the remote operation was a
12681
**   DELETE, then add no change to the rebased changeset. If the remote
12682
**   operation was an UPDATE, then the old.* fields of change are updated
12683
**   to reflect the new.* values in the UPDATE.
12684
**
12685
** <dt>Local UPDATE<dd>
12686
**   This may conflict with a remote UPDATE or DELETE. If it conflicts
12687
**   with a DELETE, and the conflict resolution was OMIT, then the update
12688
**   is changed into an INSERT. Any undefined values in the new.* record
12689
**   from the update change are filled in using the old.* values from
12690
**   the conflicting DELETE. Or, if the conflict resolution was REPLACE,
12691
**   the UPDATE change is simply omitted from the rebased changeset.
12692
**
12693
**   If conflict is with a remote UPDATE and the resolution is OMIT, then
12694
**   the old.* values are rebased using the new.* values in the remote
12695
**   change. Or, if the resolution is REPLACE, then the change is copied
12696
**   into the rebased changeset with updates to columns also updated by
12697
**   the conflicting remote UPDATE removed. If this means no columns would
12698
**   be updated, the change is omitted.
12699
** </dl>
12700
**
12701
** A local change may be rebased against multiple remote changes
12702
** simultaneously. If a single key is modified by multiple remote
12703
** changesets, they are combined as follows before the local changeset
12704
** is rebased:
12705
**
12706
** <ul>
12707
**    <li> If there has been one or more REPLACE resolutions on a
12708
**         key, it is rebased according to a REPLACE.
12709
**
12710
**    <li> If there have been no REPLACE resolutions on a key, then
12711
**         the local changeset is rebased according to the most recent
12712
**         of the OMIT resolutions.
12713
** </ul>
12714
**
12715
** Note that conflict resolutions from multiple remote changesets are
12716
** combined on a per-field basis, not per-row. This means that in the
12717
** case of multiple remote UPDATE operations, some fields of a single
12718
** local change may be rebased for REPLACE while others are rebased for
12719
** OMIT.
12720
**
12721
** In order to rebase a local changeset, the remote changeset must first
12722
** be applied to the local database using sqlite3changeset_apply_v2() and
12723
** the buffer of rebase information captured. Then:
12724
**
12725
** <ol>
12726
**   <li> An sqlite3_rebaser object is created by calling
12727
**        sqlite3rebaser_create().
12728
**   <li> The new object is configured with the rebase buffer obtained from
12729
**        sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure().
12730
**        If the local changeset is to be rebased against multiple remote
12731
**        changesets, then sqlite3rebaser_configure() should be called
12732
**        multiple times, in the same order that the multiple
12733
**        sqlite3changeset_apply_v2() calls were made.
12734
**   <li> Each local changeset is rebased by calling sqlite3rebaser_rebase().
12735
**   <li> The sqlite3_rebaser object is deleted by calling
12736
**        sqlite3rebaser_delete().
12737
** </ol>
12738
*/
12739
typedef struct sqlite3_rebaser sqlite3_rebaser;
12740
12741
/*
12742
** CAPI3REF: Create a changeset rebaser object.
12743
** EXPERIMENTAL
12744
**
12745
** Allocate a new changeset rebaser object. If successful, set (*ppNew) to
12746
** point to the new object and return SQLITE_OK. Otherwise, if an error
12747
** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew)
12748
** to NULL.
12749
*/
12750
SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew);
12751
12752
/*
12753
** CAPI3REF: Configure a changeset rebaser object.
12754
** EXPERIMENTAL
12755
**
12756
** Configure the changeset rebaser object to rebase changesets according
12757
** to the conflict resolutions described by buffer pRebase (size nRebase
12758
** bytes), which must have been obtained from a previous call to
12759
** sqlite3changeset_apply_v2().
12760
*/
12761
SQLITE_API int sqlite3rebaser_configure(
12762
  sqlite3_rebaser*,
12763
  int nRebase, const void *pRebase
12764
);
12765
12766
/*
12767
** CAPI3REF: Rebase a changeset
12768
** EXPERIMENTAL
12769
**
12770
** Argument pIn must point to a buffer containing a changeset nIn bytes
12771
** in size. This function allocates and populates a buffer with a copy
12772
** of the changeset rebased according to the configuration of the
12773
** rebaser object passed as the first argument. If successful, (*ppOut)
12774
** is set to point to the new buffer containing the rebased changeset and
12775
** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
12776
** responsibility of the caller to eventually free the new buffer using
12777
** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
12778
** are set to zero and an SQLite error code returned.
12779
*/
12780
SQLITE_API int sqlite3rebaser_rebase(
12781
  sqlite3_rebaser*,
12782
  int nIn, const void *pIn,
12783
  int *pnOut, void **ppOut
12784
);
12785
12786
/*
12787
** CAPI3REF: Delete a changeset rebaser object.
12788
** EXPERIMENTAL
12789
**
12790
** Delete the changeset rebaser object and all associated resources. There
12791
** should be one call to this function for each successful invocation
12792
** of sqlite3rebaser_create().
12793
*/
12794
SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p);
12795
12796
/*
12797
** CAPI3REF: Streaming Versions of API functions.
12798
**
12799
** The six streaming API xxx_strm() functions serve similar purposes to the
12800
** corresponding non-streaming API functions:
12801
**
12802
** <table border=1 style="margin-left:8ex;margin-right:8ex">
12803
**   <tr><th>Streaming function<th>Non-streaming equivalent</th>
12804
**   <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
12805
**   <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2]
12806
**   <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
12807
**   <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
12808
**   <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
12809
**   <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
12810
**   <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
12811
** </table>
12812
**
12813
** Non-streaming functions that accept changesets (or patchsets) as input
12814
** require that the entire changeset be stored in a single buffer in memory.
12815
** Similarly, those that return a changeset or patchset do so by returning
12816
** a pointer to a single large buffer allocated using sqlite3_malloc().
12817
** Normally this is convenient. However, if an application running in a
12818
** low-memory environment is required to handle very large changesets, the
12819
** large contiguous memory allocations required can become onerous.
12820
**
12821
** In order to avoid this problem, instead of a single large buffer, input
12822
** is passed to a streaming API functions by way of a callback function that
12823
** the sessions module invokes to incrementally request input data as it is
12824
** required. In all cases, a pair of API function parameters such as
12825
**
12826
**  <pre>
12827
**  &nbsp;     int nChangeset,
12828
**  &nbsp;     void *pChangeset,
12829
**  </pre>
12830
**
12831
** Is replaced by:
12832
**
12833
**  <pre>
12834
**  &nbsp;     int (*xInput)(void *pIn, void *pData, int *pnData),
12835
**  &nbsp;     void *pIn,
12836
**  </pre>
12837
**
12838
** Each time the xInput callback is invoked by the sessions module, the first
12839
** argument passed is a copy of the supplied pIn context pointer. The second
12840
** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
12841
** error occurs the xInput method should copy up to (*pnData) bytes of data
12842
** into the buffer and set (*pnData) to the actual number of bytes copied
12843
** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
12844
** should be set to zero to indicate this. Or, if an error occurs, an SQLite
12845
** error code should be returned. In all cases, if an xInput callback returns
12846
** an error, all processing is abandoned and the streaming API function
12847
** returns a copy of the error code to the caller.
12848
**
12849
** In the case of sqlite3changeset_start_strm(), the xInput callback may be
12850
** invoked by the sessions module at any point during the lifetime of the
12851
** iterator. If such an xInput callback returns an error, the iterator enters
12852
** an error state, whereby all subsequent calls to iterator functions
12853
** immediately fail with the same error code as returned by xInput.
12854
**
12855
** Similarly, streaming API functions that return changesets (or patchsets)
12856
** return them in chunks by way of a callback function instead of via a
12857
** pointer to a single large buffer. In this case, a pair of parameters such
12858
** as:
12859
**
12860
**  <pre>
12861
**  &nbsp;     int *pnChangeset,
12862
**  &nbsp;     void **ppChangeset,
12863
**  </pre>
12864
**
12865
** Is replaced by:
12866
**
12867
**  <pre>
12868
**  &nbsp;     int (*xOutput)(void *pOut, const void *pData, int nData),
12869
**  &nbsp;     void *pOut
12870
**  </pre>
12871
**
12872
** The xOutput callback is invoked zero or more times to return data to
12873
** the application. The first parameter passed to each call is a copy of the
12874
** pOut pointer supplied by the application. The second parameter, pData,
12875
** points to a buffer nData bytes in size containing the chunk of output
12876
** data being returned. If the xOutput callback successfully processes the
12877
** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
12878
** it should return some other SQLite error code. In this case processing
12879
** is immediately abandoned and the streaming API function returns a copy
12880
** of the xOutput error code to the application.
12881
**
12882
** The sessions module never invokes an xOutput callback with the third
12883
** parameter set to a value less than or equal to zero. Other than this,
12884
** no guarantees are made as to the size of the chunks of data returned.
12885
*/
12886
SQLITE_API int sqlite3changeset_apply_strm(
12887
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12888
  int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
12889
  void *pIn,                                          /* First arg for xInput */
12890
  int(*xFilter)(
12891
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12892
    const char *zTab              /* Table name */
12893
  ),
12894
  int(*xConflict)(
12895
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12896
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12897
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12898
  ),
12899
  void *pCtx                      /* First argument passed to xConflict */
12900
);
12901
SQLITE_API int sqlite3changeset_apply_v2_strm(
12902
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12903
  int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
12904
  void *pIn,                                          /* First arg for xInput */
12905
  int(*xFilter)(
12906
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12907
    const char *zTab              /* Table name */
12908
  ),
12909
  int(*xConflict)(
12910
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12911
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12912
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12913
  ),
12914
  void *pCtx,                     /* First argument passed to xConflict */
12915
  void **ppRebase, int *pnRebase,
12916
  int flags
12917
);
12918
SQLITE_API int sqlite3changeset_concat_strm(
12919
  int (*xInputA)(void *pIn, void *pData, int *pnData),
12920
  void *pInA,
12921
  int (*xInputB)(void *pIn, void *pData, int *pnData),
12922
  void *pInB,
12923
  int (*xOutput)(void *pOut, const void *pData, int nData),
12924
  void *pOut
12925
);
12926
SQLITE_API int sqlite3changeset_invert_strm(
12927
  int (*xInput)(void *pIn, void *pData, int *pnData),
12928
  void *pIn,
12929
  int (*xOutput)(void *pOut, const void *pData, int nData),
12930
  void *pOut
12931
);
12932
SQLITE_API int sqlite3changeset_start_strm(
12933
  sqlite3_changeset_iter **pp,
12934
  int (*xInput)(void *pIn, void *pData, int *pnData),
12935
  void *pIn
12936
);
12937
SQLITE_API int sqlite3changeset_start_v2_strm(
12938
  sqlite3_changeset_iter **pp,
12939
  int (*xInput)(void *pIn, void *pData, int *pnData),
12940
  void *pIn,
12941
  int flags
12942
);
12943
SQLITE_API int sqlite3session_changeset_strm(
12944
  sqlite3_session *pSession,
12945
  int (*xOutput)(void *pOut, const void *pData, int nData),
12946
  void *pOut
12947
);
12948
SQLITE_API int sqlite3session_patchset_strm(
12949
  sqlite3_session *pSession,
12950
  int (*xOutput)(void *pOut, const void *pData, int nData),
12951
  void *pOut
12952
);
12953
SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
12954
    int (*xInput)(void *pIn, void *pData, int *pnData),
12955
    void *pIn
12956
);
12957
SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
12958
    int (*xOutput)(void *pOut, const void *pData, int nData),
12959
    void *pOut
12960
);
12961
SQLITE_API int sqlite3rebaser_rebase_strm(
12962
  sqlite3_rebaser *pRebaser,
12963
  int (*xInput)(void *pIn, void *pData, int *pnData),
12964
  void *pIn,
12965
  int (*xOutput)(void *pOut, const void *pData, int nData),
12966
  void *pOut
12967
);
12968
12969
/*
12970
** CAPI3REF: Configure global parameters
12971
**
12972
** The sqlite3session_config() interface is used to make global configuration
12973
** changes to the sessions module in order to tune it to the specific needs
12974
** of the application.
12975
**
12976
** The sqlite3session_config() interface is not threadsafe. If it is invoked
12977
** while any other thread is inside any other sessions method then the
12978
** results are undefined. Furthermore, if it is invoked after any sessions
12979
** related objects have been created, the results are also undefined.
12980
**
12981
** The first argument to the sqlite3session_config() function must be one
12982
** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The
12983
** interpretation of the (void*) value passed as the second parameter and
12984
** the effect of calling this function depends on the value of the first
12985
** parameter.
12986
**
12987
** <dl>
12988
** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd>
12989
**    By default, the sessions module streaming interfaces attempt to input
12990
**    and output data in approximately 1 KiB chunks. This operand may be used
12991
**    to set and query the value of this configuration setting. The pointer
12992
**    passed as the second argument must point to a value of type (int).
12993
**    If this value is greater than 0, it is used as the new streaming data
12994
**    chunk size for both input and output. Before returning, the (int) value
12995
**    pointed to by pArg is set to the final value of the streaming interface
12996
**    chunk size.
12997
** </dl>
12998
**
12999
** This function returns SQLITE_OK if successful, or an SQLite error code
13000
** otherwise.
13001
*/
13002
SQLITE_API int sqlite3session_config(int op, void *pArg);
13003
13004
/*
13005
** CAPI3REF: Values for sqlite3session_config().
13006
*/
13007
#define SQLITE_SESSION_CONFIG_STRMSIZE 1
13008
13009
/*
13010
** Make sure we can call this stuff from C++.
13011
*/
13012
#ifdef __cplusplus
13013
}
13014
#endif
13015
13016
#endif  /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
13017
13018
/******** End of sqlite3session.h *********/
13019
/******** Begin file fts5.h *********/
13020
/*
13021
** 2014 May 31
13022
**
13023
** The author disclaims copyright to this source code.  In place of
13024
** a legal notice, here is a blessing:
13025
**
13026
**    May you do good and not evil.
13027
**    May you find forgiveness for yourself and forgive others.
13028
**    May you share freely, never taking more than you give.
13029
**
13030
******************************************************************************
13031
**
13032
** Interfaces to extend FTS5. Using the interfaces defined in this file,
13033
** FTS5 may be extended with:
13034
**
13035
**     * custom tokenizers, and
13036
**     * custom auxiliary functions.
13037
*/
13038
13039
13040
#ifndef _FTS5_H
13041
#define _FTS5_H
13042
13043
13044
#ifdef __cplusplus
13045
extern "C" {
13046
#endif
13047
13048
/*************************************************************************
13049
** CUSTOM AUXILIARY FUNCTIONS
13050
**
13051
** Virtual table implementations may overload SQL functions by implementing
13052
** the sqlite3_module.xFindFunction() method.
13053
*/
13054
13055
typedef struct Fts5ExtensionApi Fts5ExtensionApi;
13056
typedef struct Fts5Context Fts5Context;
13057
typedef struct Fts5PhraseIter Fts5PhraseIter;
13058
13059
typedef void (*fts5_extension_function)(
13060
  const Fts5ExtensionApi *pApi,   /* API offered by current FTS version */
13061
  Fts5Context *pFts,              /* First arg to pass to pApi functions */
13062
  sqlite3_context *pCtx,          /* Context for returning result/error */
13063
  int nVal,                       /* Number of values in apVal[] array */
13064
  sqlite3_value **apVal           /* Array of trailing arguments */
13065
);
13066
13067
struct Fts5PhraseIter {
13068
  const unsigned char *a;
13069
  const unsigned char *b;
13070
};
13071
13072
/*
13073
** EXTENSION API FUNCTIONS
13074
**
13075
** xUserData(pFts):
13076
**   Return a copy of the pUserData pointer passed to the xCreateFunction()
13077
**   API when the extension function was registered.
13078
**
13079
** xColumnTotalSize(pFts, iCol, pnToken):
13080
**   If parameter iCol is less than zero, set output variable *pnToken
13081
**   to the total number of tokens in the FTS5 table. Or, if iCol is
13082
**   non-negative but less than the number of columns in the table, return
13083
**   the total number of tokens in column iCol, considering all rows in
13084
**   the FTS5 table.
13085
**
13086
**   If parameter iCol is greater than or equal to the number of columns
13087
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
13088
**   an OOM condition or IO error), an appropriate SQLite error code is
13089
**   returned.
13090
**
13091
** xColumnCount(pFts):
13092
**   Return the number of columns in the table.
13093
**
13094
** xColumnSize(pFts, iCol, pnToken):
13095
**   If parameter iCol is less than zero, set output variable *pnToken
13096
**   to the total number of tokens in the current row. Or, if iCol is
13097
**   non-negative but less than the number of columns in the table, set
13098
**   *pnToken to the number of tokens in column iCol of the current row.
13099
**
13100
**   If parameter iCol is greater than or equal to the number of columns
13101
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
13102
**   an OOM condition or IO error), an appropriate SQLite error code is
13103
**   returned.
13104
**
13105
**   This function may be quite inefficient if used with an FTS5 table
13106
**   created with the "columnsize=0" option.
13107
**
13108
** xColumnText:
13109
**   If parameter iCol is less than zero, or greater than or equal to the
13110
**   number of columns in the table, SQLITE_RANGE is returned.
13111
**
13112
**   Otherwise, this function attempts to retrieve the text of column iCol of
13113
**   the current document. If successful, (*pz) is set to point to a buffer
13114
**   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
13115
**   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
13116
**   if an error occurs, an SQLite error code is returned and the final values
13117
**   of (*pz) and (*pn) are undefined.
13118
**
13119
** xPhraseCount:
13120
**   Returns the number of phrases in the current query expression.
13121
**
13122
** xPhraseSize:
13123
**   If parameter iCol is less than zero, or greater than or equal to the
13124
**   number of phrases in the current query, as returned by xPhraseCount,
13125
**   0 is returned. Otherwise, this function returns the number of tokens in
13126
**   phrase iPhrase of the query. Phrases are numbered starting from zero.
13127
**
13128
** xInstCount:
13129
**   Set *pnInst to the total number of occurrences of all phrases within
13130
**   the query within the current row. Return SQLITE_OK if successful, or
13131
**   an error code (i.e. SQLITE_NOMEM) if an error occurs.
13132
**
13133
**   This API can be quite slow if used with an FTS5 table created with the
13134
**   "detail=none" or "detail=column" option. If the FTS5 table is created
13135
**   with either "detail=none" or "detail=column" and "content=" option
13136
**   (i.e. if it is a contentless table), then this API always returns 0.
13137
**
13138
** xInst:
13139
**   Query for the details of phrase match iIdx within the current row.
13140
**   Phrase matches are numbered starting from zero, so the iIdx argument
13141
**   should be greater than or equal to zero and smaller than the value
13142
**   output by xInstCount(). If iIdx is less than zero or greater than
13143
**   or equal to the value returned by xInstCount(), SQLITE_RANGE is returned.
13144
**
13145
**   Otherwise, output parameter *piPhrase is set to the phrase number, *piCol
13146
**   to the column in which it occurs and *piOff the token offset of the
13147
**   first token of the phrase. SQLITE_OK is returned if successful, or an
13148
**   error code (i.e. SQLITE_NOMEM) if an error occurs.
13149
**
13150
**   This API can be quite slow if used with an FTS5 table created with the
13151
**   "detail=none" or "detail=column" option.
13152
**
13153
** xRowid:
13154
**   Returns the rowid of the current row.
13155
**
13156
** xTokenize:
13157
**   Tokenize text using the tokenizer belonging to the FTS5 table.
13158
**
13159
** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
13160
**   This API function is used to query the FTS table for phrase iPhrase
13161
**   of the current query. Specifically, a query equivalent to:
13162
**
13163
**       ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
13164
**
13165
**   with $p set to a phrase equivalent to the phrase iPhrase of the
13166
**   current query is executed. Any column filter that applies to
13167
**   phrase iPhrase of the current query is included in $p. For each
13168
**   row visited, the callback function passed as the fourth argument
13169
**   is invoked. The context and API objects passed to the callback
13170
**   function may be used to access the properties of each matched row.
13171
**   Invoking Api.xUserData() returns a copy of the pointer passed as
13172
**   the third argument to pUserData.
13173
**
13174
**   If parameter iPhrase is less than zero, or greater than or equal to
13175
**   the number of phrases in the query, as returned by xPhraseCount(),
13176
**   this function returns SQLITE_RANGE.
13177
**
13178
**   If the callback function returns any value other than SQLITE_OK, the
13179
**   query is abandoned and the xQueryPhrase function returns immediately.
13180
**   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
13181
**   Otherwise, the error code is propagated upwards.
13182
**
13183
**   If the query runs to completion without incident, SQLITE_OK is returned.
13184
**   Or, if some error occurs before the query completes or is aborted by
13185
**   the callback, an SQLite error code is returned.
13186
**
13187
**
13188
** xSetAuxdata(pFts5, pAux, xDelete)
13189
**
13190
**   Save the pointer passed as the second argument as the extension function's
13191
**   "auxiliary data". The pointer may then be retrieved by the current or any
13192
**   future invocation of the same fts5 extension function made as part of
13193
**   the same MATCH query using the xGetAuxdata() API.
13194
**
13195
**   Each extension function is allocated a single auxiliary data slot for
13196
**   each FTS query (MATCH expression). If the extension function is invoked
13197
**   more than once for a single FTS query, then all invocations share a
13198
**   single auxiliary data context.
13199
**
13200
**   If there is already an auxiliary data pointer when this function is
13201
**   invoked, then it is replaced by the new pointer. If an xDelete callback
13202
**   was specified along with the original pointer, it is invoked at this
13203
**   point.
13204
**
13205
**   The xDelete callback, if one is specified, is also invoked on the
13206
**   auxiliary data pointer after the FTS5 query has finished.
13207
**
13208
**   If an error (e.g. an OOM condition) occurs within this function,
13209
**   the auxiliary data is set to NULL and an error code returned. If the
13210
**   xDelete parameter was not NULL, it is invoked on the auxiliary data
13211
**   pointer before returning.
13212
**
13213
**
13214
** xGetAuxdata(pFts5, bClear)
13215
**
13216
**   Returns the current auxiliary data pointer for the fts5 extension
13217
**   function. See the xSetAuxdata() method for details.
13218
**
13219
**   If the bClear argument is non-zero, then the auxiliary data is cleared
13220
**   (set to NULL) before this function returns. In this case the xDelete,
13221
**   if any, is not invoked.
13222
**
13223
**
13224
** xRowCount(pFts5, pnRow)
13225
**
13226
**   This function is used to retrieve the total number of rows in the table.
13227
**   In other words, the same value that would be returned by:
13228
**
13229
**        SELECT count(*) FROM ftstable;
13230
**
13231
** xPhraseFirst()
13232
**   This function is used, along with type Fts5PhraseIter and the xPhraseNext
13233
**   method, to iterate through all instances of a single query phrase within
13234
**   the current row. This is the same information as is accessible via the
13235
**   xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
13236
**   to use, this API may be faster under some circumstances. To iterate
13237
**   through instances of phrase iPhrase, use the following code:
13238
**
13239
**       Fts5PhraseIter iter;
13240
**       int iCol, iOff;
13241
**       for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
13242
**           iCol>=0;
13243
**           pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
13244
**       ){
13245
**         // An instance of phrase iPhrase at offset iOff of column iCol
13246
**       }
13247
**
13248
**   The Fts5PhraseIter structure is defined above. Applications should not
13249
**   modify this structure directly - it should only be used as shown above
13250
**   with the xPhraseFirst() and xPhraseNext() API methods (and by
13251
**   xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
13252
**
13253
**   This API can be quite slow if used with an FTS5 table created with the
13254
**   "detail=none" or "detail=column" option. If the FTS5 table is created
13255
**   with either "detail=none" or "detail=column" and "content=" option
13256
**   (i.e. if it is a contentless table), then this API always iterates
13257
**   through an empty set (all calls to xPhraseFirst() set iCol to -1).
13258
**
13259
**   In all cases, matches are visited in (column ASC, offset ASC) order.
13260
**   i.e. all those in column 0, sorted by offset, followed by those in
13261
**   column 1, etc.
13262
**
13263
** xPhraseNext()
13264
**   See xPhraseFirst above.
13265
**
13266
** xPhraseFirstColumn()
13267
**   This function and xPhraseNextColumn() are similar to the xPhraseFirst()
13268
**   and xPhraseNext() APIs described above. The difference is that instead
13269
**   of iterating through all instances of a phrase in the current row, these
13270
**   APIs are used to iterate through the set of columns in the current row
13271
**   that contain one or more instances of a specified phrase. For example:
13272
**
13273
**       Fts5PhraseIter iter;
13274
**       int iCol;
13275
**       for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
13276
**           iCol>=0;
13277
**           pApi->xPhraseNextColumn(pFts, &iter, &iCol)
13278
**       ){
13279
**         // Column iCol contains at least one instance of phrase iPhrase
13280
**       }
13281
**
13282
**   This API can be quite slow if used with an FTS5 table created with the
13283
**   "detail=none" option. If the FTS5 table is created with either
13284
**   "detail=none" "content=" option (i.e. if it is a contentless table),
13285
**   then this API always iterates through an empty set (all calls to
13286
**   xPhraseFirstColumn() set iCol to -1).
13287
**
13288
**   The information accessed using this API and its companion
13289
**   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
13290
**   (or xInst/xInstCount). The chief advantage of this API is that it is
13291
**   significantly more efficient than those alternatives when used with
13292
**   "detail=column" tables.
13293
**
13294
** xPhraseNextColumn()
13295
**   See xPhraseFirstColumn above.
13296
**
13297
** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken)
13298
**   This is used to access token iToken of phrase iPhrase of the current
13299
**   query. Before returning, output parameter *ppToken is set to point
13300
**   to a buffer containing the requested token, and *pnToken to the
13301
**   size of this buffer in bytes.
13302
**
13303
**   If iPhrase or iToken are less than zero, or if iPhrase is greater than
13304
**   or equal to the number of phrases in the query as reported by
13305
**   xPhraseCount(), or if iToken is equal to or greater than the number of
13306
**   tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken
13307
     are both zeroed.
13308
**
13309
**   The output text is not a copy of the query text that specified the
13310
**   token. It is the output of the tokenizer module. For tokendata=1
13311
**   tables, this includes any embedded 0x00 and trailing data.
13312
**
13313
** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken)
13314
**   This is used to access token iToken of phrase hit iIdx within the
13315
**   current row. If iIdx is less than zero or greater than or equal to the
13316
**   value returned by xInstCount(), SQLITE_RANGE is returned.  Otherwise,
13317
**   output variable (*ppToken) is set to point to a buffer containing the
13318
**   matching document token, and (*pnToken) to the size of that buffer in
13319
**   bytes.
13320
**
13321
**   The output text is not a copy of the document text that was tokenized.
13322
**   It is the output of the tokenizer module. For tokendata=1 tables, this
13323
**   includes any embedded 0x00 and trailing data.
13324
**
13325
**   This API may be slow in some cases if the token identified by parameters
13326
**   iIdx and iToken matched a prefix token in the query. In most cases, the
13327
**   first call to this API for each prefix token in the query is forced
13328
**   to scan the portion of the full-text index that matches the prefix
13329
**   token to collect the extra data required by this API. If the prefix
13330
**   token matches a large number of token instances in the document set,
13331
**   this may be a performance problem.
13332
**
13333
**   If the user knows in advance that a query may use this API for a
13334
**   prefix token, FTS5 may be configured to collect all required data as part
13335
**   of the initial querying of the full-text index, avoiding the second scan
13336
**   entirely. This also causes prefix queries that do not use this API to
13337
**   run more slowly and use more memory. FTS5 may be configured in this way
13338
**   either on a per-table basis using the [FTS5 insttoken | 'insttoken']
13339
**   option, or on a per-query basis using the
13340
**   [fts5_insttoken | fts5_insttoken()] user function.
13341
**
13342
**   This API can be quite slow if used with an FTS5 table created with the
13343
**   "detail=none" or "detail=column" option.
13344
**
13345
** xColumnLocale(pFts5, iIdx, pzLocale, pnLocale)
13346
**   If parameter iCol is less than zero, or greater than or equal to the
13347
**   number of columns in the table, SQLITE_RANGE is returned.
13348
**
13349
**   Otherwise, this function attempts to retrieve the locale associated
13350
**   with column iCol of the current row. Usually, there is no associated
13351
**   locale, and output parameters (*pzLocale) and (*pnLocale) are set
13352
**   to NULL and 0, respectively. However, if the fts5_locale() function
13353
**   was used to associate a locale with the value when it was inserted
13354
**   into the fts5 table, then (*pzLocale) is set to point to a nul-terminated
13355
**   buffer containing the name of the locale in utf-8 encoding. (*pnLocale)
13356
**   is set to the size in bytes of the buffer, not including the
13357
**   nul-terminator.
13358
**
13359
**   If successful, SQLITE_OK is returned. Or, if an error occurs, an
13360
**   SQLite error code is returned. The final value of the output parameters
13361
**   is undefined in this case.
13362
**
13363
** xTokenize_v2:
13364
**   Tokenize text using the tokenizer belonging to the FTS5 table. This
13365
**   API is the same as the xTokenize() API, except that it allows a tokenizer
13366
**   locale to be specified.
13367
*/
13368
struct Fts5ExtensionApi {
13369
  int iVersion;                   /* Currently always set to 4 */
13370
13371
  void *(*xUserData)(Fts5Context*);
13372
13373
  int (*xColumnCount)(Fts5Context*);
13374
  int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
13375
  int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
13376
13377
  int (*xTokenize)(Fts5Context*,
13378
    const char *pText, int nText, /* Text to tokenize */
13379
    void *pCtx,                   /* Context passed to xToken() */
13380
    int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
13381
  );
13382
13383
  int (*xPhraseCount)(Fts5Context*);
13384
  int (*xPhraseSize)(Fts5Context*, int iPhrase);
13385
13386
  int (*xInstCount)(Fts5Context*, int *pnInst);
13387
  int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
13388
13389
  sqlite3_int64 (*xRowid)(Fts5Context*);
13390
  int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
13391
  int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
13392
13393
  int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
13394
    int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
13395
  );
13396
  int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
13397
  void *(*xGetAuxdata)(Fts5Context*, int bClear);
13398
13399
  int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
13400
  void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
13401
13402
  int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
13403
  void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
13404
13405
  /* Below this point are iVersion>=3 only */
13406
  int (*xQueryToken)(Fts5Context*,
13407
      int iPhrase, int iToken,
13408
      const char **ppToken, int *pnToken
13409
  );
13410
  int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*);
13411
13412
  /* Below this point are iVersion>=4 only */
13413
  int (*xColumnLocale)(Fts5Context*, int iCol, const char **pz, int *pn);
13414
  int (*xTokenize_v2)(Fts5Context*,
13415
    const char *pText, int nText,      /* Text to tokenize */
13416
    const char *pLocale, int nLocale,  /* Locale to pass to tokenizer */
13417
    void *pCtx,                        /* Context passed to xToken() */
13418
    int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
13419
  );
13420
};
13421
13422
/*
13423
** CUSTOM AUXILIARY FUNCTIONS
13424
*************************************************************************/
13425
13426
/*************************************************************************
13427
** CUSTOM TOKENIZERS
13428
**
13429
** Applications may also register custom tokenizer types. A tokenizer
13430
** is registered by providing fts5 with a populated instance of the
13431
** following structure. All structure methods must be defined, setting
13432
** any member of the fts5_tokenizer struct to NULL leads to undefined
13433
** behaviour. The structure methods are expected to function as follows:
13434
**
13435
** xCreate:
13436
**   This function is used to allocate and initialize a tokenizer instance.
13437
**   A tokenizer instance is required to actually tokenize text.
13438
**
13439
**   The first argument passed to this function is a copy of the (void*)
13440
**   pointer provided by the application when the fts5_tokenizer_v2 object
13441
**   was registered with FTS5 (the third argument to xCreateTokenizer()).
13442
**   The second and third arguments are an array of nul-terminated strings
13443
**   containing the tokenizer arguments, if any, specified following the
13444
**   tokenizer name as part of the CREATE VIRTUAL TABLE statement used
13445
**   to create the FTS5 table.
13446
**
13447
**   The final argument is an output variable. If successful, (*ppOut)
13448
**   should be set to point to the new tokenizer handle and SQLITE_OK
13449
**   returned. If an error occurs, some value other than SQLITE_OK should
13450
**   be returned. In this case, fts5 assumes that the final value of *ppOut
13451
**   is undefined.
13452
**
13453
** xDelete:
13454
**   This function is invoked to delete a tokenizer handle previously
13455
**   allocated using xCreate(). Fts5 guarantees that this function will
13456
**   be invoked exactly once for each successful call to xCreate().
13457
**
13458
** xTokenize:
13459
**   This function is expected to tokenize the nText byte string indicated
13460
**   by argument pText. pText may or may not be nul-terminated. The first
13461
**   argument passed to this function is a pointer to an Fts5Tokenizer object
13462
**   returned by an earlier call to xCreate().
13463
**
13464
**   The third argument indicates the reason that FTS5 is requesting
13465
**   tokenization of the supplied text. This is always one of the following
13466
**   four values:
13467
**
13468
**   <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
13469
**            or removed from the FTS table. The tokenizer is being invoked to
13470
**            determine the set of tokens to add to (or delete from) the
13471
**            FTS index.
13472
**
13473
**       <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
13474
**            against the FTS index. The tokenizer is being called to tokenize
13475
**            a bareword or quoted string specified as part of the query.
13476
**
13477
**       <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
13478
**            FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
13479
**            followed by a "*" character, indicating that the last token
13480
**            returned by the tokenizer will be treated as a token prefix.
13481
**
13482
**       <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
13483
**            satisfy an fts5_api.xTokenize() request made by an auxiliary
13484
**            function. Or an fts5_api.xColumnSize() request made by the same
13485
**            on a columnsize=0 database.
13486
**   </ul>
13487
**
13488
**   The sixth and seventh arguments passed to xTokenize() - pLocale and
13489
**   nLocale - are a pointer to a buffer containing the locale to use for
13490
**   tokenization (e.g. "en_US") and its size in bytes, respectively. The
13491
**   pLocale buffer is not nul-terminated. pLocale may be passed NULL (in
13492
**   which case nLocale is always 0) to indicate that the tokenizer should
13493
**   use its default locale.
13494
**
13495
**   For each token in the input string, the supplied callback xToken() must
13496
**   be invoked. The first argument to it should be a copy of the pointer
13497
**   passed as the second argument to xTokenize(). The third and fourth
13498
**   arguments are a pointer to a buffer containing the token text, and the
13499
**   size of the token in bytes. The 4th and 5th arguments are the byte offsets
13500
**   of the first byte of and first byte immediately following the text from
13501
**   which the token is derived within the input.
13502
**
13503
**   The second argument passed to the xToken() callback ("tflags") should
13504
**   normally be set to 0. The exception is if the tokenizer supports
13505
**   synonyms. In this case see the discussion below for details.
13506
**
13507
**   FTS5 assumes the xToken() callback is invoked for each token in the
13508
**   order that they occur within the input text.
13509
**
13510
**   If an xToken() callback returns any value other than SQLITE_OK, then
13511
**   the tokenization should be abandoned and the xTokenize() method should
13512
**   immediately return a copy of the xToken() return value. Or, if the
13513
**   input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
13514
**   if an error occurs with the xTokenize() implementation itself, it
13515
**   may abandon the tokenization and return any error code other than
13516
**   SQLITE_OK or SQLITE_DONE.
13517
**
13518
**   If the tokenizer is registered using an fts5_tokenizer_v2 object,
13519
**   then the xTokenize() method has two additional arguments - pLocale
13520
**   and nLocale. These specify the locale that the tokenizer should use
13521
**   for the current request. If pLocale and nLocale are both 0, then the
13522
**   tokenizer should use its default locale. Otherwise, pLocale points to
13523
**   an nLocale byte buffer containing the name of the locale to use as utf-8
13524
**   text. pLocale is not nul-terminated.
13525
**
13526
** FTS5_TOKENIZER
13527
**
13528
** There is also an fts5_tokenizer object. This is an older, deprecated,
13529
** version of fts5_tokenizer_v2. It is similar except that:
13530
**
13531
**  <ul>
13532
**    <li> There is no "iVersion" field, and
13533
**    <li> The xTokenize() method does not take a locale argument.
13534
**  </ul>
13535
**
13536
** Legacy fts5_tokenizer tokenizers must be registered using the
13537
** legacy xCreateTokenizer() function, instead of xCreateTokenizer_v2().
13538
**
13539
** Tokenizer implementations registered using either API may be retrieved
13540
** using both xFindTokenizer() and xFindTokenizer_v2().
13541
**
13542
** SYNONYM SUPPORT
13543
**
13544
**   Custom tokenizers may also support synonyms. Consider a case in which a
13545
**   user wishes to query for a phrase such as "first place". Using the
13546
**   built-in tokenizers, the FTS5 query 'first + place' will match instances
13547
**   of "first place" within the document set, but not alternative forms
13548
**   such as "1st place". In some applications, it would be better to match
13549
**   all instances of "first place" or "1st place" regardless of which form
13550
**   the user specified in the MATCH query text.
13551
**
13552
**   There are several ways to approach this in FTS5:
13553
**
13554
**   <ol><li> By mapping all synonyms to a single token. In this case, using
13555
**            the above example, this means that the tokenizer returns the
13556
**            same token for inputs "first" and "1st". Say that token is in
13557
**            fact "first", so that when the user inserts the document "I won
13558
**            1st place" entries are added to the index for tokens "i", "won",
13559
**            "first" and "place". If the user then queries for '1st + place',
13560
**            the tokenizer substitutes "first" for "1st" and the query works
13561
**            as expected.
13562
**
13563
**       <li> By querying the index for all synonyms of each query term
13564
**            separately. In this case, when tokenizing query text, the
13565
**            tokenizer may provide multiple synonyms for a single term
13566
**            within the document. FTS5 then queries the index for each
13567
**            synonym individually. For example, faced with the query:
13568
**
13569
**   <codeblock>
13570
**     ... MATCH 'first place'</codeblock>
13571
**
13572
**            the tokenizer offers both "1st" and "first" as synonyms for the
13573
**            first token in the MATCH query and FTS5 effectively runs a query
13574
**            similar to:
13575
**
13576
**   <codeblock>
13577
**     ... MATCH '(first OR 1st) place'</codeblock>
13578
**
13579
**            except that, for the purposes of auxiliary functions, the query
13580
**            still appears to contain just two phrases - "(first OR 1st)"
13581
**            being treated as a single phrase.
13582
**
13583
**       <li> By adding multiple synonyms for a single term to the FTS index.
13584
**            Using this method, when tokenizing document text, the tokenizer
13585
**            provides multiple synonyms for each token. So that when a
13586
**            document such as "I won first place" is tokenized, entries are
13587
**            added to the FTS index for "i", "won", "first", "1st" and
13588
**            "place".
13589
**
13590
**            This way, even if the tokenizer does not provide synonyms
13591
**            when tokenizing query text (it should not - to do so would be
13592
**            inefficient), it doesn't matter if the user queries for
13593
**            'first + place' or '1st + place', as there are entries in the
13594
**            FTS index corresponding to both forms of the first token.
13595
**   </ol>
13596
**
13597
**   Whether it is parsing document or query text, any call to xToken that
13598
**   specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
13599
**   is considered to supply a synonym for the previous token. For example,
13600
**   when parsing the document "I won first place", a tokenizer that supports
13601
**   synonyms would call xToken() 5 times, as follows:
13602
**
13603
**   <codeblock>
13604
**       xToken(pCtx, 0, "i",                      1,  0,  1);
13605
**       xToken(pCtx, 0, "won",                    3,  2,  5);
13606
**       xToken(pCtx, 0, "first",                  5,  6, 11);
13607
**       xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3,  6, 11);
13608
**       xToken(pCtx, 0, "place",                  5, 12, 17);
13609
**</codeblock>
13610
**
13611
**   It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
13612
**   xToken() is called. Multiple synonyms may be specified for a single token
13613
**   by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
13614
**   There is no limit to the number of synonyms that may be provided for a
13615
**   single token.
13616
**
13617
**   In many cases, method (1) above is the best approach. It does not add
13618
**   extra data to the FTS index or require FTS5 to query for multiple terms,
13619
**   so it is efficient in terms of disk space and query speed. However, it
13620
**   does not support prefix queries very well. If, as suggested above, the
13621
**   token "first" is substituted for "1st" by the tokenizer, then the query:
13622
**
13623
**   <codeblock>
13624
**     ... MATCH '1s*'</codeblock>
13625
**
13626
**   will not match documents that contain the token "1st" (as the tokenizer
13627
**   will probably not map "1s" to any prefix of "first").
13628
**
13629
**   For full prefix support, method (3) may be preferred. In this case,
13630
**   because the index contains entries for both "first" and "1st", prefix
13631
**   queries such as 'fi*' or '1s*' will match correctly. However, because
13632
**   extra entries are added to the FTS index, this method uses more space
13633
**   within the database.
13634
**
13635
**   Method (2) offers a midpoint between (1) and (3). Using this method,
13636
**   a query such as '1s*' will match documents that contain the literal
13637
**   token "1st", but not "first" (assuming the tokenizer is not able to
13638
**   provide synonyms for prefixes). However, a non-prefix query like '1st'
13639
**   will match against "1st" and "first". This method does not require
13640
**   extra disk space, as no extra entries are added to the FTS index.
13641
**   On the other hand, it may require more CPU cycles to run MATCH queries,
13642
**   as separate queries of the FTS index are required for each synonym.
13643
**
13644
**   When using methods (2) or (3), it is important that the tokenizer only
13645
**   provide synonyms when tokenizing document text (method (3)) or query
13646
**   text (method (2)), not both. Doing so will not cause any errors, but is
13647
**   inefficient.
13648
*/
13649
typedef struct Fts5Tokenizer Fts5Tokenizer;
13650
typedef struct fts5_tokenizer_v2 fts5_tokenizer_v2;
13651
struct fts5_tokenizer_v2 {
13652
  int iVersion;             /* Currently always 2 */
13653
13654
  int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
13655
  void (*xDelete)(Fts5Tokenizer*);
13656
  int (*xTokenize)(Fts5Tokenizer*,
13657
      void *pCtx,
13658
      int flags,            /* Mask of FTS5_TOKENIZE_* flags */
13659
      const char *pText, int nText,
13660
      const char *pLocale, int nLocale,
13661
      int (*xToken)(
13662
        void *pCtx,         /* Copy of 2nd argument to xTokenize() */
13663
        int tflags,         /* Mask of FTS5_TOKEN_* flags */
13664
        const char *pToken, /* Pointer to buffer containing token */
13665
        int nToken,         /* Size of token in bytes */
13666
        int iStart,         /* Byte offset of token within input text */
13667
        int iEnd            /* Byte offset of end of token within input text */
13668
      )
13669
  );
13670
};
13671
13672
/*
13673
** New code should use the fts5_tokenizer_v2 type to define tokenizer
13674
** implementations. The following type is included for legacy applications
13675
** that still use it.
13676
*/
13677
typedef struct fts5_tokenizer fts5_tokenizer;
13678
struct fts5_tokenizer {
13679
  int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
13680
  void (*xDelete)(Fts5Tokenizer*);
13681
  int (*xTokenize)(Fts5Tokenizer*,
13682
      void *pCtx,
13683
      int flags,            /* Mask of FTS5_TOKENIZE_* flags */
13684
      const char *pText, int nText,
13685
      int (*xToken)(
13686
        void *pCtx,         /* Copy of 2nd argument to xTokenize() */
13687
        int tflags,         /* Mask of FTS5_TOKEN_* flags */
13688
        const char *pToken, /* Pointer to buffer containing token */
13689
        int nToken,         /* Size of token in bytes */
13690
        int iStart,         /* Byte offset of token within input text */
13691
        int iEnd            /* Byte offset of end of token within input text */
13692
      )
13693
  );
13694
};
13695
13696
13697
/* Flags that may be passed as the third argument to xTokenize() */
13698
#define FTS5_TOKENIZE_QUERY     0x0001
13699
#define FTS5_TOKENIZE_PREFIX    0x0002
13700
#define FTS5_TOKENIZE_DOCUMENT  0x0004
13701
#define FTS5_TOKENIZE_AUX       0x0008
13702
13703
/* Flags that may be passed by the tokenizer implementation back to FTS5
13704
** as the third argument to the supplied xToken callback. */
13705
#define FTS5_TOKEN_COLOCATED    0x0001      /* Same position as prev. token */
13706
13707
/*
13708
** END OF CUSTOM TOKENIZERS
13709
*************************************************************************/
13710
13711
/*************************************************************************
13712
** FTS5 EXTENSION REGISTRATION API
13713
*/
13714
typedef struct fts5_api fts5_api;
13715
struct fts5_api {
13716
  int iVersion;                   /* Currently always set to 3 */
13717
13718
  /* Create a new tokenizer */
13719
  int (*xCreateTokenizer)(
13720
    fts5_api *pApi,
13721
    const char *zName,
13722
    void *pUserData,
13723
    fts5_tokenizer *pTokenizer,
13724
    void (*xDestroy)(void*)
13725
  );
13726
13727
  /* Find an existing tokenizer */
13728
  int (*xFindTokenizer)(
13729
    fts5_api *pApi,
13730
    const char *zName,
13731
    void **ppUserData,
13732
    fts5_tokenizer *pTokenizer
13733
  );
13734
13735
  /* Create a new auxiliary function */
13736
  int (*xCreateFunction)(
13737
    fts5_api *pApi,
13738
    const char *zName,
13739
    void *pUserData,
13740
    fts5_extension_function xFunction,
13741
    void (*xDestroy)(void*)
13742
  );
13743
13744
  /* APIs below this point are only available if iVersion>=3 */
13745
13746
  /* Create a new tokenizer */
13747
  int (*xCreateTokenizer_v2)(
13748
    fts5_api *pApi,
13749
    const char *zName,
13750
    void *pUserData,
13751
    fts5_tokenizer_v2 *pTokenizer,
13752
    void (*xDestroy)(void*)
13753
  );
13754
13755
  /* Find an existing tokenizer */
13756
  int (*xFindTokenizer_v2)(
13757
    fts5_api *pApi,
13758
    const char *zName,
13759
    void **ppUserData,
13760
    fts5_tokenizer_v2 **ppTokenizer
13761
  );
13762
};
13763
13764
/*
13765
** END OF REGISTRATION API
13766
*************************************************************************/
13767
13768
#ifdef __cplusplus
13769
}  /* end of the 'extern "C"' block */
13770
#endif
13771
13772
#endif /* _FTS5_H */
13773
13774
/******** End of fts5.h *********/
13775
#endif /* SQLITE3_H */