Coverage Report

Created: 2017-11-12 13:27

/home/liu/buildslave/linux-x64-runtests/build/lib/3rdparty/sqlite3/sqlite3.h
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/*
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** 2001 September 15
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**
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** The author disclaims copyright to this source code.  In place of
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** a legal notice, here is a blessing:
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**
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**    May you do good and not evil.
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**    May you find forgiveness for yourself and forgive others.
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**    May you share freely, never taking more than you give.
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**
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*************************************************************************
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** This header file defines the interface that the SQLite library
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** presents to client programs.  If a C-function, structure, datatype,
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** or constant definition does not appear in this file, then it is
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** not a published API of SQLite, is subject to change without
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** notice, and should not be referenced by programs that use SQLite.
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**
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** Some of the definitions that are in this file are marked as
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** "experimental".  Experimental interfaces are normally new
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** features recently added to SQLite.  We do not anticipate changes
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** to experimental interfaces but reserve the right to make minor changes
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** if experience from use "in the wild" suggest such changes are prudent.
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**
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** The official C-language API documentation for SQLite is derived
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** from comments in this file.  This file is the authoritative source
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** on how SQLite interfaces are suppose to operate.
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**
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** The name of this file under configuration management is "sqlite.h.in".
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** The makefile makes some minor changes to this file (such as inserting
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** the version number) and changes its name to "sqlite3.h" as
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** part of the build process.
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*/
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#ifndef _SQLITE3_H_
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#define _SQLITE3_H_
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#include <stdarg.h>     /* Needed for the definition of va_list */
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37
/*
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** Make sure we can call this stuff from C++.
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*/
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#ifdef __cplusplus
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extern "C" {
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#endif
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/*
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** Add the ability to override 'extern'
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*/
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#ifndef SQLITE_EXTERN
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# define SQLITE_EXTERN extern
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#endif
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#ifndef SQLITE_API
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# define SQLITE_API
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#endif
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56
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/*
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** These no-op macros are used in front of interfaces to mark those
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** interfaces as either deprecated or experimental.  New applications
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** should not use deprecated interfaces - they are support for backwards
61
** compatibility only.  Application writers should be aware that
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** experimental interfaces are subject to change in point releases.
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**
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** These macros used to resolve to various kinds of compiler magic that
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** would generate warning messages when they were used.  But that
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** compiler magic ended up generating such a flurry of bug reports
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** that we have taken it all out and gone back to using simple
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** noop macros.
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*/
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#define SQLITE_DEPRECATED
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#define SQLITE_EXPERIMENTAL
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/*
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** Ensure these symbols were not defined by some previous header file.
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*/
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#ifdef SQLITE_VERSION
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# undef SQLITE_VERSION
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#endif
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#ifdef SQLITE_VERSION_NUMBER
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# undef SQLITE_VERSION_NUMBER
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#endif
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/*
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** CAPI3REF: Compile-Time Library Version Numbers
85
**
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** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
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** evaluates to a string literal that is the SQLite version in the
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** format "X.Y.Z" where X is the major version number (always 3 for
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** SQLite3) and Y is the minor version number and Z is the release number.)^
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** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
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** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
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** numbers used in [SQLITE_VERSION].)^
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** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
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** be larger than the release from which it is derived.  Either Y will
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** be held constant and Z will be incremented or else Y will be incremented
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** and Z will be reset to zero.
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**
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** Since version 3.6.18, SQLite source code has been stored in the
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** <a href="http://www.fossil-scm.org/">Fossil configuration management
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** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
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** a string which identifies a particular check-in of SQLite
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** within its configuration management system.  ^The SQLITE_SOURCE_ID
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** string contains the date and time of the check-in (UTC) and an SHA1
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** hash of the entire source tree.
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**
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** See also: [sqlite3_libversion()],
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** [sqlite3_libversion_number()], [sqlite3_sourceid()],
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** [sqlite_version()] and [sqlite_source_id()].
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*/
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#define SQLITE_VERSION        "3.8.2"
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#define SQLITE_VERSION_NUMBER 3008002
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#define SQLITE_SOURCE_ID      "2013-12-06 14:53:30 27392118af4c38c5203a04b8013e1afdb1cebd0d"
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/*
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** CAPI3REF: Run-Time Library Version Numbers
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** KEYWORDS: sqlite3_version, sqlite3_sourceid
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**
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** These interfaces provide the same information as the [SQLITE_VERSION],
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** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
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** but are associated with the library instead of the header file.  ^(Cautious
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** programmers might include assert() statements in their application to
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** verify that values returned by these interfaces match the macros in
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** the header, and thus insure that the application is
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** compiled with matching library and header files.
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**
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** <blockquote><pre>
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** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
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** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
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** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
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** </pre></blockquote>)^
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**
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** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
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** macro.  ^The sqlite3_libversion() function returns a pointer to the
134
** to the sqlite3_version[] string constant.  The sqlite3_libversion()
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** function is provided for use in DLLs since DLL users usually do not have
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** direct access to string constants within the DLL.  ^The
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** sqlite3_libversion_number() function returns an integer equal to
138
** [SQLITE_VERSION_NUMBER].  ^The sqlite3_sourceid() function returns 
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** a pointer to a string constant whose value is the same as the 
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** [SQLITE_SOURCE_ID] C preprocessor macro.
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**
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** See also: [sqlite_version()] and [sqlite_source_id()].
143
*/
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SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
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SQLITE_API const char *sqlite3_libversion(void);
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SQLITE_API const char *sqlite3_sourceid(void);
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SQLITE_API int sqlite3_libversion_number(void);
148
149
/*
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** CAPI3REF: Run-Time Library Compilation Options Diagnostics
151
**
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** ^The sqlite3_compileoption_used() function returns 0 or 1 
153
** indicating whether the specified option was defined at 
154
** compile time.  ^The SQLITE_ prefix may be omitted from the 
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** option name passed to sqlite3_compileoption_used().  
156
**
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** ^The sqlite3_compileoption_get() function allows iterating
158
** over the list of options that were defined at compile time by
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** returning the N-th compile time option string.  ^If N is out of range,
160
** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_ 
161
** prefix is omitted from any strings returned by 
162
** sqlite3_compileoption_get().
163
**
164
** ^Support for the diagnostic functions sqlite3_compileoption_used()
165
** and sqlite3_compileoption_get() may be omitted by specifying the 
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** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
167
**
168
** See also: SQL functions [sqlite_compileoption_used()] and
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** [sqlite_compileoption_get()] and the [compile_options pragma].
170
*/
171
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
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SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
173
SQLITE_API const char *sqlite3_compileoption_get(int N);
174
#endif
175
176
/*
177
** CAPI3REF: Test To See If The Library Is Threadsafe
178
**
179
** ^The sqlite3_threadsafe() function returns zero if and only if
180
** SQLite was compiled with mutexing code omitted due to the
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** [SQLITE_THREADSAFE] compile-time option being set to 0.
182
**
183
** SQLite can be compiled with or without mutexes.  When
184
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
185
** are enabled and SQLite is threadsafe.  When the
186
** [SQLITE_THREADSAFE] macro is 0, 
187
** the mutexes are omitted.  Without the mutexes, it is not safe
188
** to use SQLite concurrently from more than one thread.
189
**
190
** Enabling mutexes incurs a measurable performance penalty.
191
** So if speed is of utmost importance, it makes sense to disable
192
** the mutexes.  But for maximum safety, mutexes should be enabled.
193
** ^The default behavior is for mutexes to be enabled.
194
**
195
** This interface can be used by an application to make sure that the
196
** version of SQLite that it is linking against was compiled with
197
** the desired setting of the [SQLITE_THREADSAFE] macro.
198
**
199
** This interface only reports on the compile-time mutex setting
200
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
201
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
202
** can be fully or partially disabled using a call to [sqlite3_config()]
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** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
204
** or [SQLITE_CONFIG_MUTEX].  ^(The return value of the
205
** sqlite3_threadsafe() function shows only the compile-time setting of
206
** thread safety, not any run-time changes to that setting made by
207
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
208
** is unchanged by calls to sqlite3_config().)^
209
**
210
** See the [threading mode] documentation for additional information.
211
*/
212
SQLITE_API int sqlite3_threadsafe(void);
213
214
/*
215
** CAPI3REF: Database Connection Handle
216
** KEYWORDS: {database connection} {database connections}
217
**
218
** Each open SQLite database is represented by a pointer to an instance of
219
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
220
** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
221
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
222
** and [sqlite3_close_v2()] are its destructors.  There are many other
223
** interfaces (such as
224
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
225
** [sqlite3_busy_timeout()] to name but three) that are methods on an
226
** sqlite3 object.
227
*/
228
typedef struct sqlite3 sqlite3;
229
230
/*
231
** CAPI3REF: 64-Bit Integer Types
232
** KEYWORDS: sqlite_int64 sqlite_uint64
233
**
234
** Because there is no cross-platform way to specify 64-bit integer types
235
** SQLite includes typedefs for 64-bit signed and unsigned integers.
236
**
237
** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
238
** The sqlite_int64 and sqlite_uint64 types are supported for backwards
239
** compatibility only.
240
**
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** ^The sqlite3_int64 and sqlite_int64 types can store integer values
242
** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
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** sqlite3_uint64 and sqlite_uint64 types can store integer values 
244
** between 0 and +18446744073709551615 inclusive.
245
*/
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#ifdef SQLITE_INT64_TYPE
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  typedef SQLITE_INT64_TYPE sqlite_int64;
248
  typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
249
#elif defined(_MSC_VER) || defined(__BORLANDC__)
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  typedef __int64 sqlite_int64;
251
  typedef unsigned __int64 sqlite_uint64;
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#else
253
  typedef long long int sqlite_int64;
254
  typedef unsigned long long int sqlite_uint64;
255
#endif
256
typedef sqlite_int64 sqlite3_int64;
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typedef sqlite_uint64 sqlite3_uint64;
258
259
/*
260
** If compiling for a processor that lacks floating point support,
261
** substitute integer for floating-point.
262
*/
263
#ifdef SQLITE_OMIT_FLOATING_POINT
264
# define double sqlite3_int64
265
#endif
266
267
/*
268
** CAPI3REF: Closing A Database Connection
269
**
270
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
271
** for the [sqlite3] object.
272
** ^Calls to sqlite3_close() and sqlite3_close_v2() return SQLITE_OK if
273
** the [sqlite3] object is successfully destroyed and all associated
274
** resources are deallocated.
275
**
276
** ^If the database connection is associated with unfinalized prepared
277
** statements or unfinished sqlite3_backup objects then sqlite3_close()
278
** will leave the database connection open and return [SQLITE_BUSY].
279
** ^If sqlite3_close_v2() is called with unfinalized prepared statements
280
** and unfinished sqlite3_backups, then the database connection becomes
281
** an unusable "zombie" which will automatically be deallocated when the
282
** last prepared statement is finalized or the last sqlite3_backup is
283
** finished.  The sqlite3_close_v2() interface is intended for use with
284
** host languages that are garbage collected, and where the order in which
285
** destructors are called is arbitrary.
286
**
287
** Applications should [sqlite3_finalize | finalize] all [prepared statements],
288
** [sqlite3_blob_close | close] all [BLOB handles], and 
289
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
290
** with the [sqlite3] object prior to attempting to close the object.  ^If
291
** sqlite3_close_v2() is called on a [database connection] that still has
292
** outstanding [prepared statements], [BLOB handles], and/or
293
** [sqlite3_backup] objects then it returns SQLITE_OK but the deallocation
294
** of resources is deferred until all [prepared statements], [BLOB handles],
295
** and [sqlite3_backup] objects are also destroyed.
296
**
297
** ^If an [sqlite3] object is destroyed while a transaction is open,
298
** the transaction is automatically rolled back.
299
**
300
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
301
** must be either a NULL
302
** pointer or an [sqlite3] object pointer obtained
303
** from [sqlite3_open()], [sqlite3_open16()], or
304
** [sqlite3_open_v2()], and not previously closed.
305
** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
306
** argument is a harmless no-op.
307
*/
308
SQLITE_API int sqlite3_close(sqlite3*);
309
SQLITE_API int sqlite3_close_v2(sqlite3*);
310
311
/*
312
** The type for a callback function.
313
** This is legacy and deprecated.  It is included for historical
314
** compatibility and is not documented.
315
*/
316
typedef int (*sqlite3_callback)(void*,int,char**, char**);
317
318
/*
319
** CAPI3REF: One-Step Query Execution Interface
320
**
321
** The sqlite3_exec() interface is a convenience wrapper around
322
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
323
** that allows an application to run multiple statements of SQL
324
** without having to use a lot of C code. 
325
**
326
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
327
** semicolon-separate SQL statements passed into its 2nd argument,
328
** in the context of the [database connection] passed in as its 1st
329
** argument.  ^If the callback function of the 3rd argument to
330
** sqlite3_exec() is not NULL, then it is invoked for each result row
331
** coming out of the evaluated SQL statements.  ^The 4th argument to
332
** sqlite3_exec() is relayed through to the 1st argument of each
333
** callback invocation.  ^If the callback pointer to sqlite3_exec()
334
** is NULL, then no callback is ever invoked and result rows are
335
** ignored.
336
**
337
** ^If an error occurs while evaluating the SQL statements passed into
338
** sqlite3_exec(), then execution of the current statement stops and
339
** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
340
** is not NULL then any error message is written into memory obtained
341
** from [sqlite3_malloc()] and passed back through the 5th parameter.
342
** To avoid memory leaks, the application should invoke [sqlite3_free()]
343
** on error message strings returned through the 5th parameter of
344
** of sqlite3_exec() after the error message string is no longer needed.
345
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
346
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
347
** NULL before returning.
348
**
349
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
350
** routine returns SQLITE_ABORT without invoking the callback again and
351
** without running any subsequent SQL statements.
352
**
353
** ^The 2nd argument to the sqlite3_exec() callback function is the
354
** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
355
** callback is an array of pointers to strings obtained as if from
356
** [sqlite3_column_text()], one for each column.  ^If an element of a
357
** result row is NULL then the corresponding string pointer for the
358
** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
359
** sqlite3_exec() callback is an array of pointers to strings where each
360
** entry represents the name of corresponding result column as obtained
361
** from [sqlite3_column_name()].
362
**
363
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
364
** to an empty string, or a pointer that contains only whitespace and/or 
365
** SQL comments, then no SQL statements are evaluated and the database
366
** is not changed.
367
**
368
** Restrictions:
369
**
370
** <ul>
371
** <li> The application must insure that the 1st parameter to sqlite3_exec()
372
**      is a valid and open [database connection].
373
** <li> The application must not close the [database connection] specified by
374
**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
375
** <li> The application must not modify the SQL statement text passed into
376
**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
377
** </ul>
378
*/
379
SQLITE_API int sqlite3_exec(
380
  sqlite3*,                                  /* An open database */
381
  const char *sql,                           /* SQL to be evaluated */
382
  int (*callback)(void*,int,char**,char**),  /* Callback function */
383
  void *,                                    /* 1st argument to callback */
384
  char **errmsg                              /* Error msg written here */
385
);
386
387
/*
388
** CAPI3REF: Result Codes
389
** KEYWORDS: SQLITE_OK {error code} {error codes}
390
** KEYWORDS: {result code} {result codes}
391
**
392
** Many SQLite functions return an integer result code from the set shown
393
** here in order to indicate success or failure.
394
**
395
** New error codes may be added in future versions of SQLite.
396
**
397
** See also: [SQLITE_IOERR_READ | extended result codes],
398
** [sqlite3_vtab_on_conflict()] [SQLITE_ROLLBACK | result codes].
399
*/
400
10
#define SQLITE_OK           0   /* Successful result */
401
/* beginning-of-error-codes */
402
#define SQLITE_ERROR        1   /* SQL error or missing database */
403
#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
404
#define SQLITE_PERM         3   /* Access permission denied */
405
#define SQLITE_ABORT        4   /* Callback routine requested an abort */
406
#define SQLITE_BUSY         5   /* The database file is locked */
407
#define SQLITE_LOCKED       6   /* A table in the database is locked */
408
#define SQLITE_NOMEM        7   /* A malloc() failed */
409
#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
410
#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
411
#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
412
#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
413
#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
414
#define SQLITE_FULL        13   /* Insertion failed because database is full */
415
#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
416
#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
417
#define SQLITE_EMPTY       16   /* Database is empty */
418
#define SQLITE_SCHEMA      17   /* The database schema changed */
419
#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
420
#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
421
#define SQLITE_MISMATCH    20   /* Data type mismatch */
422
#define SQLITE_MISUSE      21   /* Library used incorrectly */
423
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
424
#define SQLITE_AUTH        23   /* Authorization denied */
425
#define SQLITE_FORMAT      24   /* Auxiliary database format error */
426
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
427
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
428
#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
429
#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
430
82
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
431
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
432
/* end-of-error-codes */
433
434
/*
435
** CAPI3REF: Extended Result Codes
436
** KEYWORDS: {extended error code} {extended error codes}
437
** KEYWORDS: {extended result code} {extended result codes}
438
**
439
** In its default configuration, SQLite API routines return one of 26 integer
440
** [SQLITE_OK | result codes].  However, experience has shown that many of
441
** these result codes are too coarse-grained.  They do not provide as
442
** much information about problems as programmers might like.  In an effort to
443
** address this, newer versions of SQLite (version 3.3.8 and later) include
444
** support for additional result codes that provide more detailed information
445
** about errors. The extended result codes are enabled or disabled
446
** on a per database connection basis using the
447
** [sqlite3_extended_result_codes()] API.
448
**
449
** Some of the available extended result codes are listed here.
450
** One may expect the number of extended result codes will increase
451
** over time.  Software that uses extended result codes should expect
452
** to see new result codes in future releases of SQLite.
453
**
454
** The SQLITE_OK result code will never be extended.  It will always
455
** be exactly zero.
456
*/
457
#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
458
#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
459
#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
460
#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
461
#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
462
#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
463
#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
464
#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
465
#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
466
#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
467
#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
468
#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
469
#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
470
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
471
#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
472
#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
473
#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
474
#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
475
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
476
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
477
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
478
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
479
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
480
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
481
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
482
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
483
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
484
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
485
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
486
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
487
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
488
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
489
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
490
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
491
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
492
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
493
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
494
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
495
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
496
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
497
#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
498
#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
499
#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
500
#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
501
#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
502
#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
503
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
504
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
505
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
506
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
507
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
508
509
/*
510
** CAPI3REF: Flags For File Open Operations
511
**
512
** These bit values are intended for use in the
513
** 3rd parameter to the [sqlite3_open_v2()] interface and
514
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
515
*/
516
#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
517
#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
518
#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
519
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
520
#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
521
#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
522
#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
523
#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
524
#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
525
#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
526
#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
527
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
528
#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
529
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
530
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
531
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
532
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
533
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
534
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
535
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
536
537
/* Reserved:                         0x00F00000 */
538
539
/*
540
** CAPI3REF: Device Characteristics
541
**
542
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
543
** object returns an integer which is a vector of these
544
** bit values expressing I/O characteristics of the mass storage
545
** device that holds the file that the [sqlite3_io_methods]
546
** refers to.
547
**
548
** The SQLITE_IOCAP_ATOMIC property means that all writes of
549
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
550
** mean that writes of blocks that are nnn bytes in size and
551
** are aligned to an address which is an integer multiple of
552
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
553
** that when data is appended to a file, the data is appended
554
** first then the size of the file is extended, never the other
555
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
556
** information is written to disk in the same order as calls
557
** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
558
** after reboot following a crash or power loss, the only bytes in a
559
** file that were written at the application level might have changed
560
** and that adjacent bytes, even bytes within the same sector are
561
** guaranteed to be unchanged.
562
*/
563
#define SQLITE_IOCAP_ATOMIC                 0x00000001
564
#define SQLITE_IOCAP_ATOMIC512              0x00000002
565
#define SQLITE_IOCAP_ATOMIC1K               0x00000004
566
#define SQLITE_IOCAP_ATOMIC2K               0x00000008
567
#define SQLITE_IOCAP_ATOMIC4K               0x00000010
568
#define SQLITE_IOCAP_ATOMIC8K               0x00000020
569
#define SQLITE_IOCAP_ATOMIC16K              0x00000040
570
#define SQLITE_IOCAP_ATOMIC32K              0x00000080
571
#define SQLITE_IOCAP_ATOMIC64K              0x00000100
572
#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
573
#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
574
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
575
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
576
577
/*
578
** CAPI3REF: File Locking Levels
579
**
580
** SQLite uses one of these integer values as the second
581
** argument to calls it makes to the xLock() and xUnlock() methods
582
** of an [sqlite3_io_methods] object.
583
*/
584
#define SQLITE_LOCK_NONE          0
585
#define SQLITE_LOCK_SHARED        1
586
#define SQLITE_LOCK_RESERVED      2
587
#define SQLITE_LOCK_PENDING       3
588
#define SQLITE_LOCK_EXCLUSIVE     4
589
590
/*
591
** CAPI3REF: Synchronization Type Flags
592
**
593
** When SQLite invokes the xSync() method of an
594
** [sqlite3_io_methods] object it uses a combination of
595
** these integer values as the second argument.
596
**
597
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
598
** sync operation only needs to flush data to mass storage.  Inode
599
** information need not be flushed. If the lower four bits of the flag
600
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
601
** If the lower four bits equal SQLITE_SYNC_FULL, that means
602
** to use Mac OS X style fullsync instead of fsync().
603
**
604
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
605
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
606
** settings.  The [synchronous pragma] determines when calls to the
607
** xSync VFS method occur and applies uniformly across all platforms.
608
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
609
** energetic or rigorous or forceful the sync operations are and
610
** only make a difference on Mac OSX for the default SQLite code.
611
** (Third-party VFS implementations might also make the distinction
612
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
613
** operating systems natively supported by SQLite, only Mac OSX
614
** cares about the difference.)
615
*/
616
#define SQLITE_SYNC_NORMAL        0x00002
617
#define SQLITE_SYNC_FULL          0x00003
618
#define SQLITE_SYNC_DATAONLY      0x00010
619
620
/*
621
** CAPI3REF: OS Interface Open File Handle
622
**
623
** An [sqlite3_file] object represents an open file in the 
624
** [sqlite3_vfs | OS interface layer].  Individual OS interface
625
** implementations will
626
** want to subclass this object by appending additional fields
627
** for their own use.  The pMethods entry is a pointer to an
628
** [sqlite3_io_methods] object that defines methods for performing
629
** I/O operations on the open file.
630
*/
631
typedef struct sqlite3_file sqlite3_file;
632
struct sqlite3_file {
633
  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
634
};
635
636
/*
637
** CAPI3REF: OS Interface File Virtual Methods Object
638
**
639
** Every file opened by the [sqlite3_vfs.xOpen] method populates an
640
** [sqlite3_file] object (or, more commonly, a subclass of the
641
** [sqlite3_file] object) with a pointer to an instance of this object.
642
** This object defines the methods used to perform various operations
643
** against the open file represented by the [sqlite3_file] object.
644
**
645
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 
646
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
647
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
648
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
649
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
650
** to NULL.
651
**
652
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
653
** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
654
** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
655
** flag may be ORed in to indicate that only the data of the file
656
** and not its inode needs to be synced.
657
**
658
** The integer values to xLock() and xUnlock() are one of
659
** <ul>
660
** <li> [SQLITE_LOCK_NONE],
661
** <li> [SQLITE_LOCK_SHARED],
662
** <li> [SQLITE_LOCK_RESERVED],
663
** <li> [SQLITE_LOCK_PENDING], or
664
** <li> [SQLITE_LOCK_EXCLUSIVE].
665
** </ul>
666
** xLock() increases the lock. xUnlock() decreases the lock.
667
** The xCheckReservedLock() method checks whether any database connection,
668
** either in this process or in some other process, is holding a RESERVED,
669
** PENDING, or EXCLUSIVE lock on the file.  It returns true
670
** if such a lock exists and false otherwise.
671
**
672
** The xFileControl() method is a generic interface that allows custom
673
** VFS implementations to directly control an open file using the
674
** [sqlite3_file_control()] interface.  The second "op" argument is an
675
** integer opcode.  The third argument is a generic pointer intended to
676
** point to a structure that may contain arguments or space in which to
677
** write return values.  Potential uses for xFileControl() might be
678
** functions to enable blocking locks with timeouts, to change the
679
** locking strategy (for example to use dot-file locks), to inquire
680
** about the status of a lock, or to break stale locks.  The SQLite
681
** core reserves all opcodes less than 100 for its own use.
682
** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
683
** Applications that define a custom xFileControl method should use opcodes
684
** greater than 100 to avoid conflicts.  VFS implementations should
685
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
686
** recognize.
687
**
688
** The xSectorSize() method returns the sector size of the
689
** device that underlies the file.  The sector size is the
690
** minimum write that can be performed without disturbing
691
** other bytes in the file.  The xDeviceCharacteristics()
692
** method returns a bit vector describing behaviors of the
693
** underlying device:
694
**
695
** <ul>
696
** <li> [SQLITE_IOCAP_ATOMIC]
697
** <li> [SQLITE_IOCAP_ATOMIC512]
698
** <li> [SQLITE_IOCAP_ATOMIC1K]
699
** <li> [SQLITE_IOCAP_ATOMIC2K]
700
** <li> [SQLITE_IOCAP_ATOMIC4K]
701
** <li> [SQLITE_IOCAP_ATOMIC8K]
702
** <li> [SQLITE_IOCAP_ATOMIC16K]
703
** <li> [SQLITE_IOCAP_ATOMIC32K]
704
** <li> [SQLITE_IOCAP_ATOMIC64K]
705
** <li> [SQLITE_IOCAP_SAFE_APPEND]
706
** <li> [SQLITE_IOCAP_SEQUENTIAL]
707
** </ul>
708
**
709
** The SQLITE_IOCAP_ATOMIC property means that all writes of
710
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
711
** mean that writes of blocks that are nnn bytes in size and
712
** are aligned to an address which is an integer multiple of
713
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
714
** that when data is appended to a file, the data is appended
715
** first then the size of the file is extended, never the other
716
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
717
** information is written to disk in the same order as calls
718
** to xWrite().
719
**
720
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
721
** in the unread portions of the buffer with zeros.  A VFS that
722
** fails to zero-fill short reads might seem to work.  However,
723
** failure to zero-fill short reads will eventually lead to
724
** database corruption.
725
*/
726
typedef struct sqlite3_io_methods sqlite3_io_methods;
727
struct sqlite3_io_methods {
728
  int iVersion;
729
  int (*xClose)(sqlite3_file*);
730
  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
731
  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
732
  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
733
  int (*xSync)(sqlite3_file*, int flags);
734
  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
735
  int (*xLock)(sqlite3_file*, int);
736
  int (*xUnlock)(sqlite3_file*, int);
737
  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
738
  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
739
  int (*xSectorSize)(sqlite3_file*);
740
  int (*xDeviceCharacteristics)(sqlite3_file*);
741
  /* Methods above are valid for version 1 */
742
  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
743
  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
744
  void (*xShmBarrier)(sqlite3_file*);
745
  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
746
  /* Methods above are valid for version 2 */
747
  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
748
  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
749
  /* Methods above are valid for version 3 */
750
  /* Additional methods may be added in future releases */
751
};
752
753
/*
754
** CAPI3REF: Standard File Control Opcodes
755
**
756
** These integer constants are opcodes for the xFileControl method
757
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
758
** interface.
759
**
760
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
761
** opcode causes the xFileControl method to write the current state of
762
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
763
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
764
** into an integer that the pArg argument points to. This capability
765
** is used during testing and only needs to be supported when SQLITE_TEST
766
** is defined.
767
** <ul>
768
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
769
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
770
** layer a hint of how large the database file will grow to be during the
771
** current transaction.  This hint is not guaranteed to be accurate but it
772
** is often close.  The underlying VFS might choose to preallocate database
773
** file space based on this hint in order to help writes to the database
774
** file run faster.
775
**
776
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
777
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
778
** extends and truncates the database file in chunks of a size specified
779
** by the user. The fourth argument to [sqlite3_file_control()] should 
780
** point to an integer (type int) containing the new chunk-size to use
781
** for the nominated database. Allocating database file space in large
782
** chunks (say 1MB at a time), may reduce file-system fragmentation and
783
** improve performance on some systems.
784
**
785
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
786
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
787
** to the [sqlite3_file] object associated with a particular database
788
** connection.  See the [sqlite3_file_control()] documentation for
789
** additional information.
790
**
791
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
792
** ^(The [SQLITE_FCNTL_SYNC_OMITTED] opcode is generated internally by
793
** SQLite and sent to all VFSes in place of a call to the xSync method
794
** when the database connection has [PRAGMA synchronous] set to OFF.)^
795
** Some specialized VFSes need this signal in order to operate correctly
796
** when [PRAGMA synchronous | PRAGMA synchronous=OFF] is set, but most 
797
** VFSes do not need this signal and should silently ignore this opcode.
798
** Applications should not call [sqlite3_file_control()] with this
799
** opcode as doing so may disrupt the operation of the specialized VFSes
800
** that do require it.  
801
**
802
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
803
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
804
** retry counts and intervals for certain disk I/O operations for the
805
** windows [VFS] in order to provide robustness in the presence of
806
** anti-virus programs.  By default, the windows VFS will retry file read,
807
** file write, and file delete operations up to 10 times, with a delay
808
** of 25 milliseconds before the first retry and with the delay increasing
809
** by an additional 25 milliseconds with each subsequent retry.  This
810
** opcode allows these two values (10 retries and 25 milliseconds of delay)
811
** to be adjusted.  The values are changed for all database connections
812
** within the same process.  The argument is a pointer to an array of two
813
** integers where the first integer i the new retry count and the second
814
** integer is the delay.  If either integer is negative, then the setting
815
** is not changed but instead the prior value of that setting is written
816
** into the array entry, allowing the current retry settings to be
817
** interrogated.  The zDbName parameter is ignored.
818
**
819
** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
820
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
821
** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
822
** write ahead log and shared memory files used for transaction control
823
** are automatically deleted when the latest connection to the database
824
** closes.  Setting persistent WAL mode causes those files to persist after
825
** close.  Persisting the files is useful when other processes that do not
826
** have write permission on the directory containing the database file want
827
** to read the database file, as the WAL and shared memory files must exist
828
** in order for the database to be readable.  The fourth parameter to
829
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
830
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
831
** WAL mode.  If the integer is -1, then it is overwritten with the current
832
** WAL persistence setting.
833
**
834
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
835
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
836
** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
837
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
838
** xDeviceCharacteristics methods. The fourth parameter to
839
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
840
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
841
** mode.  If the integer is -1, then it is overwritten with the current
842
** zero-damage mode setting.
843
**
844
** <li>[[SQLITE_FCNTL_OVERWRITE]]
845
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
846
** a write transaction to indicate that, unless it is rolled back for some
847
** reason, the entire database file will be overwritten by the current 
848
** transaction. This is used by VACUUM operations.
849
**
850
** <li>[[SQLITE_FCNTL_VFSNAME]]
851
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
852
** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
853
** final bottom-level VFS are written into memory obtained from 
854
** [sqlite3_malloc()] and the result is stored in the char* variable
855
** that the fourth parameter of [sqlite3_file_control()] points to.
856
** The caller is responsible for freeing the memory when done.  As with
857
** all file-control actions, there is no guarantee that this will actually
858
** do anything.  Callers should initialize the char* variable to a NULL
859
** pointer in case this file-control is not implemented.  This file-control
860
** is intended for diagnostic use only.
861
**
862
** <li>[[SQLITE_FCNTL_PRAGMA]]
863
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 
864
** file control is sent to the open [sqlite3_file] object corresponding
865
** to the database file to which the pragma statement refers. ^The argument
866
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
867
** pointers to strings (char**) in which the second element of the array
868
** is the name of the pragma and the third element is the argument to the
869
** pragma or NULL if the pragma has no argument.  ^The handler for an
870
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
871
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
872
** or the equivalent and that string will become the result of the pragma or
873
** the error message if the pragma fails. ^If the
874
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 
875
** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
876
** file control returns [SQLITE_OK], then the parser assumes that the
877
** VFS has handled the PRAGMA itself and the parser generates a no-op
878
** prepared statement.  ^If the [SQLITE_FCNTL_PRAGMA] file control returns
879
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
880
** that the VFS encountered an error while handling the [PRAGMA] and the
881
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
882
** file control occurs at the beginning of pragma statement analysis and so
883
** it is able to override built-in [PRAGMA] statements.
884
**
885
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
886
** ^The [SQLITE_FCNTL_BUSYHANDLER]
887
** file-control may be invoked by SQLite on the database file handle
888
** shortly after it is opened in order to provide a custom VFS with access
889
** to the connections busy-handler callback. The argument is of type (void **)
890
** - an array of two (void *) values. The first (void *) actually points
891
** to a function of type (int (*)(void *)). In order to invoke the connections
892
** busy-handler, this function should be invoked with the second (void *) in
893
** the array as the only argument. If it returns non-zero, then the operation
894
** should be retried. If it returns zero, the custom VFS should abandon the
895
** current operation.
896
**
897
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
898
** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
899
** to have SQLite generate a
900
** temporary filename using the same algorithm that is followed to generate
901
** temporary filenames for TEMP tables and other internal uses.  The
902
** argument should be a char** which will be filled with the filename
903
** written into memory obtained from [sqlite3_malloc()].  The caller should
904
** invoke [sqlite3_free()] on the result to avoid a memory leak.
905
**
906
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
907
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
908
** maximum number of bytes that will be used for memory-mapped I/O.
909
** The argument is a pointer to a value of type sqlite3_int64 that
910
** is an advisory maximum number of bytes in the file to memory map.  The
911
** pointer is overwritten with the old value.  The limit is not changed if
912
** the value originally pointed to is negative, and so the current limit 
913
** can be queried by passing in a pointer to a negative number.  This
914
** file-control is used internally to implement [PRAGMA mmap_size].
915
**
916
** <li>[[SQLITE_FCNTL_TRACE]]
917
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
918
** to the VFS about what the higher layers of the SQLite stack are doing.
919
** This file control is used by some VFS activity tracing [shims].
920
** The argument is a zero-terminated string.  Higher layers in the
921
** SQLite stack may generate instances of this file control if
922
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
923
**
924
** </ul>
925
*/
926
#define SQLITE_FCNTL_LOCKSTATE               1
927
#define SQLITE_GET_LOCKPROXYFILE             2
928
#define SQLITE_SET_LOCKPROXYFILE             3
929
#define SQLITE_LAST_ERRNO                    4
930
#define SQLITE_FCNTL_SIZE_HINT               5
931
#define SQLITE_FCNTL_CHUNK_SIZE              6
932
#define SQLITE_FCNTL_FILE_POINTER            7
933
#define SQLITE_FCNTL_SYNC_OMITTED            8
934
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
935
#define SQLITE_FCNTL_PERSIST_WAL            10
936
#define SQLITE_FCNTL_OVERWRITE              11
937
#define SQLITE_FCNTL_VFSNAME                12
938
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
939
#define SQLITE_FCNTL_PRAGMA                 14
940
#define SQLITE_FCNTL_BUSYHANDLER            15
941
#define SQLITE_FCNTL_TEMPFILENAME           16
942
#define SQLITE_FCNTL_MMAP_SIZE              18
943
#define SQLITE_FCNTL_TRACE                  19
944
945
/*
946
** CAPI3REF: Mutex Handle
947
**
948
** The mutex module within SQLite defines [sqlite3_mutex] to be an
949
** abstract type for a mutex object.  The SQLite core never looks
950
** at the internal representation of an [sqlite3_mutex].  It only
951
** deals with pointers to the [sqlite3_mutex] object.
952
**
953
** Mutexes are created using [sqlite3_mutex_alloc()].
954
*/
955
typedef struct sqlite3_mutex sqlite3_mutex;
956
957
/*
958
** CAPI3REF: OS Interface Object
959
**
960
** An instance of the sqlite3_vfs object defines the interface between
961
** the SQLite core and the underlying operating system.  The "vfs"
962
** in the name of the object stands for "virtual file system".  See
963
** the [VFS | VFS documentation] for further information.
964
**
965
** The value of the iVersion field is initially 1 but may be larger in
966
** future versions of SQLite.  Additional fields may be appended to this
967
** object when the iVersion value is increased.  Note that the structure
968
** of the sqlite3_vfs object changes in the transaction between
969
** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
970
** modified.
971
**
972
** The szOsFile field is the size of the subclassed [sqlite3_file]
973
** structure used by this VFS.  mxPathname is the maximum length of
974
** a pathname in this VFS.
975
**
976
** Registered sqlite3_vfs objects are kept on a linked list formed by
977
** the pNext pointer.  The [sqlite3_vfs_register()]
978
** and [sqlite3_vfs_unregister()] interfaces manage this list
979
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
980
** searches the list.  Neither the application code nor the VFS
981
** implementation should use the pNext pointer.
982
**
983
** The pNext field is the only field in the sqlite3_vfs
984
** structure that SQLite will ever modify.  SQLite will only access
985
** or modify this field while holding a particular static mutex.
986
** The application should never modify anything within the sqlite3_vfs
987
** object once the object has been registered.
988
**
989
** The zName field holds the name of the VFS module.  The name must
990
** be unique across all VFS modules.
991
**
992
** [[sqlite3_vfs.xOpen]]
993
** ^SQLite guarantees that the zFilename parameter to xOpen
994
** is either a NULL pointer or string obtained
995
** from xFullPathname() with an optional suffix added.
996
** ^If a suffix is added to the zFilename parameter, it will
997
** consist of a single "-" character followed by no more than
998
** 11 alphanumeric and/or "-" characters.
999
** ^SQLite further guarantees that
1000
** the string will be valid and unchanged until xClose() is
1001
** called. Because of the previous sentence,
1002
** the [sqlite3_file] can safely store a pointer to the
1003
** filename if it needs to remember the filename for some reason.
1004
** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1005
** must invent its own temporary name for the file.  ^Whenever the 
1006
** xFilename parameter is NULL it will also be the case that the
1007
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1008
**
1009
** The flags argument to xOpen() includes all bits set in
1010
** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
1011
** or [sqlite3_open16()] is used, then flags includes at least
1012
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 
1013
** If xOpen() opens a file read-only then it sets *pOutFlags to
1014
** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1015
**
1016
** ^(SQLite will also add one of the following flags to the xOpen()
1017
** call, depending on the object being opened:
1018
**
1019
** <ul>
1020
** <li>  [SQLITE_OPEN_MAIN_DB]
1021
** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
1022
** <li>  [SQLITE_OPEN_TEMP_DB]
1023
** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
1024
** <li>  [SQLITE_OPEN_TRANSIENT_DB]
1025
** <li>  [SQLITE_OPEN_SUBJOURNAL]
1026
** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
1027
** <li>  [SQLITE_OPEN_WAL]
1028
** </ul>)^
1029
**
1030
** The file I/O implementation can use the object type flags to
1031
** change the way it deals with files.  For example, an application
1032
** that does not care about crash recovery or rollback might make
1033
** the open of a journal file a no-op.  Writes to this journal would
1034
** also be no-ops, and any attempt to read the journal would return
1035
** SQLITE_IOERR.  Or the implementation might recognize that a database
1036
** file will be doing page-aligned sector reads and writes in a random
1037
** order and set up its I/O subsystem accordingly.
1038
**
1039
** SQLite might also add one of the following flags to the xOpen method:
1040
**
1041
** <ul>
1042
** <li> [SQLITE_OPEN_DELETEONCLOSE]
1043
** <li> [SQLITE_OPEN_EXCLUSIVE]
1044
** </ul>
1045
**
1046
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1047
** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1048
** will be set for TEMP databases and their journals, transient
1049
** databases, and subjournals.
1050
**
1051
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1052
** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1053
** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1054
** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
1055
** SQLITE_OPEN_CREATE, is used to indicate that file should always
1056
** be created, and that it is an error if it already exists.
1057
** It is <i>not</i> used to indicate the file should be opened 
1058
** for exclusive access.
1059
**
1060
** ^At least szOsFile bytes of memory are allocated by SQLite
1061
** to hold the  [sqlite3_file] structure passed as the third
1062
** argument to xOpen.  The xOpen method does not have to
1063
** allocate the structure; it should just fill it in.  Note that
1064
** the xOpen method must set the sqlite3_file.pMethods to either
1065
** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1066
** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1067
** element will be valid after xOpen returns regardless of the success
1068
** or failure of the xOpen call.
1069
**
1070
** [[sqlite3_vfs.xAccess]]
1071
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1072
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1073
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1074
** to test whether a file is at least readable.   The file can be a
1075
** directory.
1076
**
1077
** ^SQLite will always allocate at least mxPathname+1 bytes for the
1078
** output buffer xFullPathname.  The exact size of the output buffer
1079
** is also passed as a parameter to both  methods. If the output buffer
1080
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1081
** handled as a fatal error by SQLite, vfs implementations should endeavor
1082
** to prevent this by setting mxPathname to a sufficiently large value.
1083
**
1084
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1085
** interfaces are not strictly a part of the filesystem, but they are
1086
** included in the VFS structure for completeness.
1087
** The xRandomness() function attempts to return nBytes bytes
1088
** of good-quality randomness into zOut.  The return value is
1089
** the actual number of bytes of randomness obtained.
1090
** The xSleep() method causes the calling thread to sleep for at
1091
** least the number of microseconds given.  ^The xCurrentTime()
1092
** method returns a Julian Day Number for the current date and time as
1093
** a floating point value.
1094
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1095
** Day Number multiplied by 86400000 (the number of milliseconds in 
1096
** a 24-hour day).  
1097
** ^SQLite will use the xCurrentTimeInt64() method to get the current
1098
** date and time if that method is available (if iVersion is 2 or 
1099
** greater and the function pointer is not NULL) and will fall back
1100
** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1101
**
1102
** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1103
** are not used by the SQLite core.  These optional interfaces are provided
1104
** by some VFSes to facilitate testing of the VFS code. By overriding 
1105
** system calls with functions under its control, a test program can
1106
** simulate faults and error conditions that would otherwise be difficult
1107
** or impossible to induce.  The set of system calls that can be overridden
1108
** varies from one VFS to another, and from one version of the same VFS to the
1109
** next.  Applications that use these interfaces must be prepared for any
1110
** or all of these interfaces to be NULL or for their behavior to change
1111
** from one release to the next.  Applications must not attempt to access
1112
** any of these methods if the iVersion of the VFS is less than 3.
1113
*/
1114
typedef struct sqlite3_vfs sqlite3_vfs;
1115
typedef void (*sqlite3_syscall_ptr)(void);
1116
struct sqlite3_vfs {
1117
  int iVersion;            /* Structure version number (currently 3) */
1118
  int szOsFile;            /* Size of subclassed sqlite3_file */
1119
  int mxPathname;          /* Maximum file pathname length */
1120
  sqlite3_vfs *pNext;      /* Next registered VFS */
1121
  const char *zName;       /* Name of this virtual file system */
1122
  void *pAppData;          /* Pointer to application-specific data */
1123
  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1124
               int flags, int *pOutFlags);
1125
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1126
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1127
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1128
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1129
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1130
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1131
  void (*xDlClose)(sqlite3_vfs*, void*);
1132
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1133
  int (*xSleep)(sqlite3_vfs*, int microseconds);
1134
  int (*xCurrentTime)(sqlite3_vfs*, double*);
1135
  int (*xGetLastError)(sqlite3_vfs*, int, char *);
1136
  /*
1137
  ** The methods above are in version 1 of the sqlite_vfs object
1138
  ** definition.  Those that follow are added in version 2 or later
1139
  */
1140
  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1141
  /*
1142
  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1143
  ** Those below are for version 3 and greater.
1144
  */
1145
  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1146
  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1147
  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1148
  /*
1149
  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1150
  ** New fields may be appended in figure versions.  The iVersion
1151
  ** value will increment whenever this happens. 
1152
  */
1153
};
1154
1155
/*
1156
** CAPI3REF: Flags for the xAccess VFS method
1157
**
1158
** These integer constants can be used as the third parameter to
1159
** the xAccess method of an [sqlite3_vfs] object.  They determine
1160
** what kind of permissions the xAccess method is looking for.
1161
** With SQLITE_ACCESS_EXISTS, the xAccess method
1162
** simply checks whether the file exists.
1163
** With SQLITE_ACCESS_READWRITE, the xAccess method
1164
** checks whether the named directory is both readable and writable
1165
** (in other words, if files can be added, removed, and renamed within
1166
** the directory).
1167
** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1168
** [temp_store_directory pragma], though this could change in a future
1169
** release of SQLite.
1170
** With SQLITE_ACCESS_READ, the xAccess method
1171
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1172
** currently unused, though it might be used in a future release of
1173
** SQLite.
1174
*/
1175
#define SQLITE_ACCESS_EXISTS    0
1176
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
1177
#define SQLITE_ACCESS_READ      2   /* Unused */
1178
1179
/*
1180
** CAPI3REF: Flags for the xShmLock VFS method
1181
**
1182
** These integer constants define the various locking operations
1183
** allowed by the xShmLock method of [sqlite3_io_methods].  The
1184
** following are the only legal combinations of flags to the
1185
** xShmLock method:
1186
**
1187
** <ul>
1188
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1189
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1190
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1191
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1192
** </ul>
1193
**
1194
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1195
** was given no the corresponding lock.  
1196
**
1197
** The xShmLock method can transition between unlocked and SHARED or
1198
** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
1199
** and EXCLUSIVE.
1200
*/
1201
#define SQLITE_SHM_UNLOCK       1
1202
#define SQLITE_SHM_LOCK         2
1203
#define SQLITE_SHM_SHARED       4
1204
#define SQLITE_SHM_EXCLUSIVE    8
1205
1206
/*
1207
** CAPI3REF: Maximum xShmLock index
1208
**
1209
** The xShmLock method on [sqlite3_io_methods] may use values
1210
** between 0 and this upper bound as its "offset" argument.
1211
** The SQLite core will never attempt to acquire or release a
1212
** lock outside of this range
1213
*/
1214
#define SQLITE_SHM_NLOCK        8
1215
1216
1217
/*
1218
** CAPI3REF: Initialize The SQLite Library
1219
**
1220
** ^The sqlite3_initialize() routine initializes the
1221
** SQLite library.  ^The sqlite3_shutdown() routine
1222
** deallocates any resources that were allocated by sqlite3_initialize().
1223
** These routines are designed to aid in process initialization and
1224
** shutdown on embedded systems.  Workstation applications using
1225
** SQLite normally do not need to invoke either of these routines.
1226
**
1227
** A call to sqlite3_initialize() is an "effective" call if it is
1228
** the first time sqlite3_initialize() is invoked during the lifetime of
1229
** the process, or if it is the first time sqlite3_initialize() is invoked
1230
** following a call to sqlite3_shutdown().  ^(Only an effective call
1231
** of sqlite3_initialize() does any initialization.  All other calls
1232
** are harmless no-ops.)^
1233
**
1234
** A call to sqlite3_shutdown() is an "effective" call if it is the first
1235
** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1236
** an effective call to sqlite3_shutdown() does any deinitialization.
1237
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1238
**
1239
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1240
** is not.  The sqlite3_shutdown() interface must only be called from a
1241
** single thread.  All open [database connections] must be closed and all
1242
** other SQLite resources must be deallocated prior to invoking
1243
** sqlite3_shutdown().
1244
**
1245
** Among other things, ^sqlite3_initialize() will invoke
1246
** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1247
** will invoke sqlite3_os_end().
1248
**
1249
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1250
** ^If for some reason, sqlite3_initialize() is unable to initialize
1251
** the library (perhaps it is unable to allocate a needed resource such
1252
** as a mutex) it returns an [error code] other than [SQLITE_OK].
1253
**
1254
** ^The sqlite3_initialize() routine is called internally by many other
1255
** SQLite interfaces so that an application usually does not need to
1256
** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1257
** calls sqlite3_initialize() so the SQLite library will be automatically
1258
** initialized when [sqlite3_open()] is called if it has not be initialized
1259
** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1260
** compile-time option, then the automatic calls to sqlite3_initialize()
1261
** are omitted and the application must call sqlite3_initialize() directly
1262
** prior to using any other SQLite interface.  For maximum portability,
1263
** it is recommended that applications always invoke sqlite3_initialize()
1264
** directly prior to using any other SQLite interface.  Future releases
1265
** of SQLite may require this.  In other words, the behavior exhibited
1266
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1267
** default behavior in some future release of SQLite.
1268
**
1269
** The sqlite3_os_init() routine does operating-system specific
1270
** initialization of the SQLite library.  The sqlite3_os_end()
1271
** routine undoes the effect of sqlite3_os_init().  Typical tasks
1272
** performed by these routines include allocation or deallocation
1273
** of static resources, initialization of global variables,
1274
** setting up a default [sqlite3_vfs] module, or setting up
1275
** a default configuration using [sqlite3_config()].
1276
**
1277
** The application should never invoke either sqlite3_os_init()
1278
** or sqlite3_os_end() directly.  The application should only invoke
1279
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1280
** interface is called automatically by sqlite3_initialize() and
1281
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1282
** implementations for sqlite3_os_init() and sqlite3_os_end()
1283
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1284
** When [custom builds | built for other platforms]
1285
** (using the [SQLITE_OS_OTHER=1] compile-time
1286
** option) the application must supply a suitable implementation for
1287
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1288
** implementation of sqlite3_os_init() or sqlite3_os_end()
1289
** must return [SQLITE_OK] on success and some other [error code] upon
1290
** failure.
1291
*/
1292
SQLITE_API int sqlite3_initialize(void);
1293
SQLITE_API int sqlite3_shutdown(void);
1294
SQLITE_API int sqlite3_os_init(void);
1295
SQLITE_API int sqlite3_os_end(void);
1296
1297
/*
1298
** CAPI3REF: Configuring The SQLite Library
1299
**
1300
** The sqlite3_config() interface is used to make global configuration
1301
** changes to SQLite in order to tune SQLite to the specific needs of
1302
** the application.  The default configuration is recommended for most
1303
** applications and so this routine is usually not necessary.  It is
1304
** provided to support rare applications with unusual needs.
1305
**
1306
** The sqlite3_config() interface is not threadsafe.  The application
1307
** must insure that no other SQLite interfaces are invoked by other
1308
** threads while sqlite3_config() is running.  Furthermore, sqlite3_config()
1309
** may only be invoked prior to library initialization using
1310
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1311
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1312
** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1313
** Note, however, that ^sqlite3_config() can be called as part of the
1314
** implementation of an application-defined [sqlite3_os_init()].
1315
**
1316
** The first argument to sqlite3_config() is an integer
1317
** [configuration option] that determines
1318
** what property of SQLite is to be configured.  Subsequent arguments
1319
** vary depending on the [configuration option]
1320
** in the first argument.
1321
**
1322
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1323
** ^If the option is unknown or SQLite is unable to set the option
1324
** then this routine returns a non-zero [error code].
1325
*/
1326
SQLITE_API int sqlite3_config(int, ...);
1327
1328
/*
1329
** CAPI3REF: Configure database connections
1330
**
1331
** The sqlite3_db_config() interface is used to make configuration
1332
** changes to a [database connection].  The interface is similar to
1333
** [sqlite3_config()] except that the changes apply to a single
1334
** [database connection] (specified in the first argument).
1335
**
1336
** The second argument to sqlite3_db_config(D,V,...)  is the
1337
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 
1338
** that indicates what aspect of the [database connection] is being configured.
1339
** Subsequent arguments vary depending on the configuration verb.
1340
**
1341
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1342
** the call is considered successful.
1343
*/
1344
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1345
1346
/*
1347
** CAPI3REF: Memory Allocation Routines
1348
**
1349
** An instance of this object defines the interface between SQLite
1350
** and low-level memory allocation routines.
1351
**
1352
** This object is used in only one place in the SQLite interface.
1353
** A pointer to an instance of this object is the argument to
1354
** [sqlite3_config()] when the configuration option is
1355
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].  
1356
** By creating an instance of this object
1357
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1358
** during configuration, an application can specify an alternative
1359
** memory allocation subsystem for SQLite to use for all of its
1360
** dynamic memory needs.
1361
**
1362
** Note that SQLite comes with several [built-in memory allocators]
1363
** that are perfectly adequate for the overwhelming majority of applications
1364
** and that this object is only useful to a tiny minority of applications
1365
** with specialized memory allocation requirements.  This object is
1366
** also used during testing of SQLite in order to specify an alternative
1367
** memory allocator that simulates memory out-of-memory conditions in
1368
** order to verify that SQLite recovers gracefully from such
1369
** conditions.
1370
**
1371
** The xMalloc, xRealloc, and xFree methods must work like the
1372
** malloc(), realloc() and free() functions from the standard C library.
1373
** ^SQLite guarantees that the second argument to
1374
** xRealloc is always a value returned by a prior call to xRoundup.
1375
**
1376
** xSize should return the allocated size of a memory allocation
1377
** previously obtained from xMalloc or xRealloc.  The allocated size
1378
** is always at least as big as the requested size but may be larger.
1379
**
1380
** The xRoundup method returns what would be the allocated size of
1381
** a memory allocation given a particular requested size.  Most memory
1382
** allocators round up memory allocations at least to the next multiple
1383
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1384
** Every memory allocation request coming in through [sqlite3_malloc()]
1385
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
1386
** that causes the corresponding memory allocation to fail.
1387
**
1388
** The xInit method initializes the memory allocator.  For example,
1389
** it might allocate any require mutexes or initialize internal data
1390
** structures.  The xShutdown method is invoked (indirectly) by
1391
** [sqlite3_shutdown()] and should deallocate any resources acquired
1392
** by xInit.  The pAppData pointer is used as the only parameter to
1393
** xInit and xShutdown.
1394
**
1395
** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1396
** the xInit method, so the xInit method need not be threadsafe.  The
1397
** xShutdown method is only called from [sqlite3_shutdown()] so it does
1398
** not need to be threadsafe either.  For all other methods, SQLite
1399
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1400
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1401
** it is by default) and so the methods are automatically serialized.
1402
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1403
** methods must be threadsafe or else make their own arrangements for
1404
** serialization.
1405
**
1406
** SQLite will never invoke xInit() more than once without an intervening
1407
** call to xShutdown().
1408
*/
1409
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1410
struct sqlite3_mem_methods {
1411
  void *(*xMalloc)(int);         /* Memory allocation function */
1412
  void (*xFree)(void*);          /* Free a prior allocation */
1413
  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1414
  int (*xSize)(void*);           /* Return the size of an allocation */
1415
  int (*xRoundup)(int);          /* Round up request size to allocation size */
1416
  int (*xInit)(void*);           /* Initialize the memory allocator */
1417
  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1418
  void *pAppData;                /* Argument to xInit() and xShutdown() */
1419
};
1420
1421
/*
1422
** CAPI3REF: Configuration Options
1423
** KEYWORDS: {configuration option}
1424
**
1425
** These constants are the available integer configuration options that
1426
** can be passed as the first argument to the [sqlite3_config()] interface.
1427
**
1428
** New configuration options may be added in future releases of SQLite.
1429
** Existing configuration options might be discontinued.  Applications
1430
** should check the return code from [sqlite3_config()] to make sure that
1431
** the call worked.  The [sqlite3_config()] interface will return a
1432
** non-zero [error code] if a discontinued or unsupported configuration option
1433
** is invoked.
1434
**
1435
** <dl>
1436
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1437
** <dd>There are no arguments to this option.  ^This option sets the
1438
** [threading mode] to Single-thread.  In other words, it disables
1439
** all mutexing and puts SQLite into a mode where it can only be used
1440
** by a single thread.   ^If SQLite is compiled with
1441
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1442
** it is not possible to change the [threading mode] from its default
1443
** value of Single-thread and so [sqlite3_config()] will return 
1444
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1445
** configuration option.</dd>
1446
**
1447
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1448
** <dd>There are no arguments to this option.  ^This option sets the
1449
** [threading mode] to Multi-thread.  In other words, it disables
1450
** mutexing on [database connection] and [prepared statement] objects.
1451
** The application is responsible for serializing access to
1452
** [database connections] and [prepared statements].  But other mutexes
1453
** are enabled so that SQLite will be safe to use in a multi-threaded
1454
** environment as long as no two threads attempt to use the same
1455
** [database connection] at the same time.  ^If SQLite is compiled with
1456
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1457
** it is not possible to set the Multi-thread [threading mode] and
1458
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1459
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1460
**
1461
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1462
** <dd>There are no arguments to this option.  ^This option sets the
1463
** [threading mode] to Serialized. In other words, this option enables
1464
** all mutexes including the recursive
1465
** mutexes on [database connection] and [prepared statement] objects.
1466
** In this mode (which is the default when SQLite is compiled with
1467
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1468
** to [database connections] and [prepared statements] so that the
1469
** application is free to use the same [database connection] or the
1470
** same [prepared statement] in different threads at the same time.
1471
** ^If SQLite is compiled with
1472
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1473
** it is not possible to set the Serialized [threading mode] and
1474
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1475
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1476
**
1477
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1478
** <dd> ^(This option takes a single argument which is a pointer to an
1479
** instance of the [sqlite3_mem_methods] structure.  The argument specifies
1480
** alternative low-level memory allocation routines to be used in place of
1481
** the memory allocation routines built into SQLite.)^ ^SQLite makes
1482
** its own private copy of the content of the [sqlite3_mem_methods] structure
1483
** before the [sqlite3_config()] call returns.</dd>
1484
**
1485
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1486
** <dd> ^(This option takes a single argument which is a pointer to an
1487
** instance of the [sqlite3_mem_methods] structure.  The [sqlite3_mem_methods]
1488
** structure is filled with the currently defined memory allocation routines.)^
1489
** This option can be used to overload the default memory allocation
1490
** routines with a wrapper that simulations memory allocation failure or
1491
** tracks memory usage, for example. </dd>
1492
**
1493
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1494
** <dd> ^This option takes single argument of type int, interpreted as a 
1495
** boolean, which enables or disables the collection of memory allocation 
1496
** statistics. ^(When memory allocation statistics are disabled, the 
1497
** following SQLite interfaces become non-operational:
1498
**   <ul>
1499
**   <li> [sqlite3_memory_used()]
1500
**   <li> [sqlite3_memory_highwater()]
1501
**   <li> [sqlite3_soft_heap_limit64()]
1502
**   <li> [sqlite3_status()]
1503
**   </ul>)^
1504
** ^Memory allocation statistics are enabled by default unless SQLite is
1505
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1506
** allocation statistics are disabled by default.
1507
** </dd>
1508
**
1509
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1510
** <dd> ^This option specifies a static memory buffer that SQLite can use for
1511
** scratch memory.  There are three arguments:  A pointer an 8-byte
1512
** aligned memory buffer from which the scratch allocations will be
1513
** drawn, the size of each scratch allocation (sz),
1514
** and the maximum number of scratch allocations (N).  The sz
1515
** argument must be a multiple of 16.
1516
** The first argument must be a pointer to an 8-byte aligned buffer
1517
** of at least sz*N bytes of memory.
1518
** ^SQLite will use no more than two scratch buffers per thread.  So
1519
** N should be set to twice the expected maximum number of threads.
1520
** ^SQLite will never require a scratch buffer that is more than 6
1521
** times the database page size. ^If SQLite needs needs additional
1522
** scratch memory beyond what is provided by this configuration option, then 
1523
** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
1524
**
1525
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1526
** <dd> ^This option specifies a static memory buffer that SQLite can use for
1527
** the database page cache with the default page cache implementation.  
1528
** This configuration should not be used if an application-define page
1529
** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
1530
** There are three arguments to this option: A pointer to 8-byte aligned
1531
** memory, the size of each page buffer (sz), and the number of pages (N).
1532
** The sz argument should be the size of the largest database page
1533
** (a power of two between 512 and 32768) plus a little extra for each
1534
** page header.  ^The page header size is 20 to 40 bytes depending on
1535
** the host architecture.  ^It is harmless, apart from the wasted memory,
1536
** to make sz a little too large.  The first
1537
** argument should point to an allocation of at least sz*N bytes of memory.
1538
** ^SQLite will use the memory provided by the first argument to satisfy its
1539
** memory needs for the first N pages that it adds to cache.  ^If additional
1540
** page cache memory is needed beyond what is provided by this option, then
1541
** SQLite goes to [sqlite3_malloc()] for the additional storage space.
1542
** The pointer in the first argument must
1543
** be aligned to an 8-byte boundary or subsequent behavior of SQLite
1544
** will be undefined.</dd>
1545
**
1546
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1547
** <dd> ^This option specifies a static memory buffer that SQLite will use
1548
** for all of its dynamic memory allocation needs beyond those provided
1549
** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
1550
** There are three arguments: An 8-byte aligned pointer to the memory,
1551
** the number of bytes in the memory buffer, and the minimum allocation size.
1552
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1553
** to using its default memory allocator (the system malloc() implementation),
1554
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1555
** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1556
** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
1557
** allocator is engaged to handle all of SQLites memory allocation needs.
1558
** The first pointer (the memory pointer) must be aligned to an 8-byte
1559
** boundary or subsequent behavior of SQLite will be undefined.
1560
** The minimum allocation size is capped at 2**12. Reasonable values
1561
** for the minimum allocation size are 2**5 through 2**8.</dd>
1562
**
1563
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1564
** <dd> ^(This option takes a single argument which is a pointer to an
1565
** instance of the [sqlite3_mutex_methods] structure.  The argument specifies
1566
** alternative low-level mutex routines to be used in place
1567
** the mutex routines built into SQLite.)^  ^SQLite makes a copy of the
1568
** content of the [sqlite3_mutex_methods] structure before the call to
1569
** [sqlite3_config()] returns. ^If SQLite is compiled with
1570
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1571
** the entire mutexing subsystem is omitted from the build and hence calls to
1572
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1573
** return [SQLITE_ERROR].</dd>
1574
**
1575
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1576
** <dd> ^(This option takes a single argument which is a pointer to an
1577
** instance of the [sqlite3_mutex_methods] structure.  The
1578
** [sqlite3_mutex_methods]
1579
** structure is filled with the currently defined mutex routines.)^
1580
** This option can be used to overload the default mutex allocation
1581
** routines with a wrapper used to track mutex usage for performance
1582
** profiling or testing, for example.   ^If SQLite is compiled with
1583
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1584
** the entire mutexing subsystem is omitted from the build and hence calls to
1585
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1586
** return [SQLITE_ERROR].</dd>
1587
**
1588
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1589
** <dd> ^(This option takes two arguments that determine the default
1590
** memory allocation for the lookaside memory allocator on each
1591
** [database connection].  The first argument is the
1592
** size of each lookaside buffer slot and the second is the number of
1593
** slots allocated to each database connection.)^  ^(This option sets the
1594
** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1595
** verb to [sqlite3_db_config()] can be used to change the lookaside
1596
** configuration on individual connections.)^ </dd>
1597
**
1598
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1599
** <dd> ^(This option takes a single argument which is a pointer to
1600
** an [sqlite3_pcache_methods2] object.  This object specifies the interface
1601
** to a custom page cache implementation.)^  ^SQLite makes a copy of the
1602
** object and uses it for page cache memory allocations.</dd>
1603
**
1604
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1605
** <dd> ^(This option takes a single argument which is a pointer to an
1606
** [sqlite3_pcache_methods2] object.  SQLite copies of the current
1607
** page cache implementation into that object.)^ </dd>
1608
**
1609
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1610
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1611
** global [error log].
1612
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1613
** function with a call signature of void(*)(void*,int,const char*), 
1614
** and a pointer to void. ^If the function pointer is not NULL, it is
1615
** invoked by [sqlite3_log()] to process each logging event.  ^If the
1616
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1617
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1618
** passed through as the first parameter to the application-defined logger
1619
** function whenever that function is invoked.  ^The second parameter to
1620
** the logger function is a copy of the first parameter to the corresponding
1621
** [sqlite3_log()] call and is intended to be a [result code] or an
1622
** [extended result code].  ^The third parameter passed to the logger is
1623
** log message after formatting via [sqlite3_snprintf()].
1624
** The SQLite logging interface is not reentrant; the logger function
1625
** supplied by the application must not invoke any SQLite interface.
1626
** In a multi-threaded application, the application-defined logger
1627
** function must be threadsafe. </dd>
1628
**
1629
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1630
** <dd>^(This option takes a single argument of type int. If non-zero, then
1631
** URI handling is globally enabled. If the parameter is zero, then URI handling
1632
** is globally disabled.)^ ^If URI handling is globally enabled, all filenames
1633
** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
1634
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1635
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1636
** connection is opened. ^If it is globally disabled, filenames are
1637
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1638
** database connection is opened. ^(By default, URI handling is globally
1639
** disabled. The default value may be changed by compiling with the
1640
** [SQLITE_USE_URI] symbol defined.)^
1641
**
1642
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1643
** <dd>^This option takes a single integer argument which is interpreted as
1644
** a boolean in order to enable or disable the use of covering indices for
1645
** full table scans in the query optimizer.  ^The default setting is determined
1646
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1647
** if that compile-time option is omitted.
1648
** The ability to disable the use of covering indices for full table scans
1649
** is because some incorrectly coded legacy applications might malfunction
1650
** when the optimization is enabled.  Providing the ability to
1651
** disable the optimization allows the older, buggy application code to work
1652
** without change even with newer versions of SQLite.
1653
**
1654
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1655
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1656
** <dd> These options are obsolete and should not be used by new code.
1657
** They are retained for backwards compatibility but are now no-ops.
1658
** </dd>
1659
**
1660
** [[SQLITE_CONFIG_SQLLOG]]
1661
** <dt>SQLITE_CONFIG_SQLLOG
1662
** <dd>This option is only available if sqlite is compiled with the
1663
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1664
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1665
** The second should be of type (void*). The callback is invoked by the library
1666
** in three separate circumstances, identified by the value passed as the
1667
** fourth parameter. If the fourth parameter is 0, then the database connection
1668
** passed as the second argument has just been opened. The third argument
1669
** points to a buffer containing the name of the main database file. If the
1670
** fourth parameter is 1, then the SQL statement that the third parameter
1671
** points to has just been executed. Or, if the fourth parameter is 2, then
1672
** the connection being passed as the second parameter is being closed. The
1673
** third parameter is passed NULL In this case.  An example of using this
1674
** configuration option can be seen in the "test_sqllog.c" source file in
1675
** the canonical SQLite source tree.</dd>
1676
**
1677
** [[SQLITE_CONFIG_MMAP_SIZE]]
1678
** <dt>SQLITE_CONFIG_MMAP_SIZE
1679
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
1680
** that are the default mmap size limit (the default setting for
1681
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
1682
** ^The default setting can be overridden by each database connection using
1683
** either the [PRAGMA mmap_size] command, or by using the
1684
** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
1685
** cannot be changed at run-time.  Nor may the maximum allowed mmap size
1686
** exceed the compile-time maximum mmap size set by the
1687
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
1688
** ^If either argument to this option is negative, then that argument is
1689
** changed to its compile-time default.
1690
**
1691
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
1692
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
1693
** <dd>^This option is only available if SQLite is compiled for Windows
1694
** with the [SQLITE_WIN32_MALLOC] pre-processor macro defined.
1695
** SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
1696
** that specifies the maximum size of the created heap.
1697
** </dl>
1698
*/
1699
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
1700
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
1701
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
1702
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
1703
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
1704
#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
1705
#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
1706
#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
1707
#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
1708
#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
1709
#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
1710
/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 
1711
#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
1712
#define SQLITE_CONFIG_PCACHE       14  /* no-op */
1713
#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
1714
#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
1715
#define SQLITE_CONFIG_URI          17  /* int */
1716
#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
1717
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
1718
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
1719
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
1720
#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
1721
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
1722
1723
/*
1724
** CAPI3REF: Database Connection Configuration Options
1725
**
1726
** These constants are the available integer configuration options that
1727
** can be passed as the second argument to the [sqlite3_db_config()] interface.
1728
**
1729
** New configuration options may be added in future releases of SQLite.
1730
** Existing configuration options might be discontinued.  Applications
1731
** should check the return code from [sqlite3_db_config()] to make sure that
1732
** the call worked.  ^The [sqlite3_db_config()] interface will return a
1733
** non-zero [error code] if a discontinued or unsupported configuration option
1734
** is invoked.
1735
**
1736
** <dl>
1737
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1738
** <dd> ^This option takes three additional arguments that determine the 
1739
** [lookaside memory allocator] configuration for the [database connection].
1740
** ^The first argument (the third parameter to [sqlite3_db_config()] is a
1741
** pointer to a memory buffer to use for lookaside memory.
1742
** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1743
** may be NULL in which case SQLite will allocate the
1744
** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1745
** size of each lookaside buffer slot.  ^The third argument is the number of
1746
** slots.  The size of the buffer in the first argument must be greater than
1747
** or equal to the product of the second and third arguments.  The buffer
1748
** must be aligned to an 8-byte boundary.  ^If the second argument to
1749
** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1750
** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
1751
** configuration for a database connection can only be changed when that
1752
** connection is not currently using lookaside memory, or in other words
1753
** when the "current value" returned by
1754
** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
1755
** Any attempt to change the lookaside memory configuration when lookaside
1756
** memory is in use leaves the configuration unchanged and returns 
1757
** [SQLITE_BUSY].)^</dd>
1758
**
1759
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
1760
** <dd> ^This option is used to enable or disable the enforcement of
1761
** [foreign key constraints].  There should be two additional arguments.
1762
** The first argument is an integer which is 0 to disable FK enforcement,
1763
** positive to enable FK enforcement or negative to leave FK enforcement
1764
** unchanged.  The second parameter is a pointer to an integer into which
1765
** is written 0 or 1 to indicate whether FK enforcement is off or on
1766
** following this call.  The second parameter may be a NULL pointer, in
1767
** which case the FK enforcement setting is not reported back. </dd>
1768
**
1769
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
1770
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
1771
** There should be two additional arguments.
1772
** The first argument is an integer which is 0 to disable triggers,
1773
** positive to enable triggers or negative to leave the setting unchanged.
1774
** The second parameter is a pointer to an integer into which
1775
** is written 0 or 1 to indicate whether triggers are disabled or enabled
1776
** following this call.  The second parameter may be a NULL pointer, in
1777
** which case the trigger setting is not reported back. </dd>
1778
**
1779
** </dl>
1780
*/
1781
#define SQLITE_DBCONFIG_LOOKASIDE       1001  /* void* int int */
1782
#define SQLITE_DBCONFIG_ENABLE_FKEY     1002  /* int int* */
1783
#define SQLITE_DBCONFIG_ENABLE_TRIGGER  1003  /* int int* */
1784
1785
1786
/*
1787
** CAPI3REF: Enable Or Disable Extended Result Codes
1788
**
1789
** ^The sqlite3_extended_result_codes() routine enables or disables the
1790
** [extended result codes] feature of SQLite. ^The extended result
1791
** codes are disabled by default for historical compatibility.
1792
*/
1793
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
1794
1795
/*
1796
** CAPI3REF: Last Insert Rowid
1797
**
1798
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
1799
** has a unique 64-bit signed
1800
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
1801
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
1802
** names are not also used by explicitly declared columns. ^If
1803
** the table has a column of type [INTEGER PRIMARY KEY] then that column
1804
** is another alias for the rowid.
1805
**
1806
** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the 
1807
** most recent successful [INSERT] into a rowid table or [virtual table]
1808
** on database connection D.
1809
** ^Inserts into [WITHOUT ROWID] tables are not recorded.
1810
** ^If no successful [INSERT]s into rowid tables
1811
** have ever occurred on the database connection D, 
1812
** then sqlite3_last_insert_rowid(D) returns zero.
1813
**
1814
** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
1815
** method, then this routine will return the [rowid] of the inserted
1816
** row as long as the trigger or virtual table method is running.
1817
** But once the trigger or virtual table method ends, the value returned 
1818
** by this routine reverts to what it was before the trigger or virtual
1819
** table method began.)^
1820
**
1821
** ^An [INSERT] that fails due to a constraint violation is not a
1822
** successful [INSERT] and does not change the value returned by this
1823
** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
1824
** and INSERT OR ABORT make no changes to the return value of this
1825
** routine when their insertion fails.  ^(When INSERT OR REPLACE
1826
** encounters a constraint violation, it does not fail.  The
1827
** INSERT continues to completion after deleting rows that caused
1828
** the constraint problem so INSERT OR REPLACE will always change
1829
** the return value of this interface.)^
1830
**
1831
** ^For the purposes of this routine, an [INSERT] is considered to
1832
** be successful even if it is subsequently rolled back.
1833
**
1834
** This function is accessible to SQL statements via the
1835
** [last_insert_rowid() SQL function].
1836
**
1837
** If a separate thread performs a new [INSERT] on the same
1838
** database connection while the [sqlite3_last_insert_rowid()]
1839
** function is running and thus changes the last insert [rowid],
1840
** then the value returned by [sqlite3_last_insert_rowid()] is
1841
** unpredictable and might not equal either the old or the new
1842
** last insert [rowid].
1843
*/
1844
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
1845
1846
/*
1847
** CAPI3REF: Count The Number Of Rows Modified
1848
**
1849
** ^This function returns the number of database rows that were changed
1850
** or inserted or deleted by the most recently completed SQL statement
1851
** on the [database connection] specified by the first parameter.
1852
** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
1853
** or [DELETE] statement are counted.  Auxiliary changes caused by
1854
** triggers or [foreign key actions] are not counted.)^ Use the
1855
** [sqlite3_total_changes()] function to find the total number of changes
1856
** including changes caused by triggers and foreign key actions.
1857
**
1858
** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
1859
** are not counted.  Only real table changes are counted.
1860
**
1861
** ^(A "row change" is a change to a single row of a single table
1862
** caused by an INSERT, DELETE, or UPDATE statement.  Rows that
1863
** are changed as side effects of [REPLACE] constraint resolution,
1864
** rollback, ABORT processing, [DROP TABLE], or by any other
1865
** mechanisms do not count as direct row changes.)^
1866
**
1867
** A "trigger context" is a scope of execution that begins and
1868
** ends with the script of a [CREATE TRIGGER | trigger]. 
1869
** Most SQL statements are
1870
** evaluated outside of any trigger.  This is the "top level"
1871
** trigger context.  If a trigger fires from the top level, a
1872
** new trigger context is entered for the duration of that one
1873
** trigger.  Subtriggers create subcontexts for their duration.
1874
**
1875
** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
1876
** not create a new trigger context.
1877
**
1878
** ^This function returns the number of direct row changes in the
1879
** most recent INSERT, UPDATE, or DELETE statement within the same
1880
** trigger context.
1881
**
1882
** ^Thus, when called from the top level, this function returns the
1883
** number of changes in the most recent INSERT, UPDATE, or DELETE
1884
** that also occurred at the top level.  ^(Within the body of a trigger,
1885
** the sqlite3_changes() interface can be called to find the number of
1886
** changes in the most recently completed INSERT, UPDATE, or DELETE
1887
** statement within the body of the same trigger.
1888
** However, the number returned does not include changes
1889
** caused by subtriggers since those have their own context.)^
1890
**
1891
** See also the [sqlite3_total_changes()] interface, the
1892
** [count_changes pragma], and the [changes() SQL function].
1893
**
1894
** If a separate thread makes changes on the same database connection
1895
** while [sqlite3_changes()] is running then the value returned
1896
** is unpredictable and not meaningful.
1897
*/
1898
SQLITE_API int sqlite3_changes(sqlite3*);
1899
1900
/*
1901
** CAPI3REF: Total Number Of Rows Modified
1902
**
1903
** ^This function returns the number of row changes caused by [INSERT],
1904
** [UPDATE] or [DELETE] statements since the [database connection] was opened.
1905
** ^(The count returned by sqlite3_total_changes() includes all changes
1906
** from all [CREATE TRIGGER | trigger] contexts and changes made by
1907
** [foreign key actions]. However,
1908
** the count does not include changes used to implement [REPLACE] constraints,
1909
** do rollbacks or ABORT processing, or [DROP TABLE] processing.  The
1910
** count does not include rows of views that fire an [INSTEAD OF trigger],
1911
** though if the INSTEAD OF trigger makes changes of its own, those changes 
1912
** are counted.)^
1913
** ^The sqlite3_total_changes() function counts the changes as soon as
1914
** the statement that makes them is completed (when the statement handle
1915
** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
1916
**
1917
** See also the [sqlite3_changes()] interface, the
1918
** [count_changes pragma], and the [total_changes() SQL function].
1919
**
1920
** If a separate thread makes changes on the same database connection
1921
** while [sqlite3_total_changes()] is running then the value
1922
** returned is unpredictable and not meaningful.
1923
*/
1924
SQLITE_API int sqlite3_total_changes(sqlite3*);
1925
1926
/*
1927
** CAPI3REF: Interrupt A Long-Running Query
1928
**
1929
** ^This function causes any pending database operation to abort and
1930
** return at its earliest opportunity. This routine is typically
1931
** called in response to a user action such as pressing "Cancel"
1932
** or Ctrl-C where the user wants a long query operation to halt
1933
** immediately.
1934
**
1935
** ^It is safe to call this routine from a thread different from the
1936
** thread that is currently running the database operation.  But it
1937
** is not safe to call this routine with a [database connection] that
1938
** is closed or might close before sqlite3_interrupt() returns.
1939
**
1940
** ^If an SQL operation is very nearly finished at the time when
1941
** sqlite3_interrupt() is called, then it might not have an opportunity
1942
** to be interrupted and might continue to completion.
1943
**
1944
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1945
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
1946
** that is inside an explicit transaction, then the entire transaction
1947
** will be rolled back automatically.
1948
**
1949
** ^The sqlite3_interrupt(D) call is in effect until all currently running
1950
** SQL statements on [database connection] D complete.  ^Any new SQL statements
1951
** that are started after the sqlite3_interrupt() call and before the 
1952
** running statements reaches zero are interrupted as if they had been
1953
** running prior to the sqlite3_interrupt() call.  ^New SQL statements
1954
** that are started after the running statement count reaches zero are
1955
** not effected by the sqlite3_interrupt().
1956
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
1957
** SQL statements is a no-op and has no effect on SQL statements
1958
** that are started after the sqlite3_interrupt() call returns.
1959
**
1960
** If the database connection closes while [sqlite3_interrupt()]
1961
** is running then bad things will likely happen.
1962
*/
1963
SQLITE_API void sqlite3_interrupt(sqlite3*);
1964
1965
/*
1966
** CAPI3REF: Determine If An SQL Statement Is Complete
1967
**
1968
** These routines are useful during command-line input to determine if the
1969
** currently entered text seems to form a complete SQL statement or
1970
** if additional input is needed before sending the text into
1971
** SQLite for parsing.  ^These routines return 1 if the input string
1972
** appears to be a complete SQL statement.  ^A statement is judged to be
1973
** complete if it ends with a semicolon token and is not a prefix of a
1974
** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
1975
** string literals or quoted identifier names or comments are not
1976
** independent tokens (they are part of the token in which they are
1977
** embedded) and thus do not count as a statement terminator.  ^Whitespace
1978
** and comments that follow the final semicolon are ignored.
1979
**
1980
** ^These routines return 0 if the statement is incomplete.  ^If a
1981
** memory allocation fails, then SQLITE_NOMEM is returned.
1982
**
1983
** ^These routines do not parse the SQL statements thus
1984
** will not detect syntactically incorrect SQL.
1985
**
1986
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 
1987
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
1988
** automatically by sqlite3_complete16().  If that initialization fails,
1989
** then the return value from sqlite3_complete16() will be non-zero
1990
** regardless of whether or not the input SQL is complete.)^
1991
**
1992
** The input to [sqlite3_complete()] must be a zero-terminated
1993
** UTF-8 string.
1994
**
1995
** The input to [sqlite3_complete16()] must be a zero-terminated
1996
** UTF-16 string in native byte order.
1997
*/
1998
SQLITE_API int sqlite3_complete(const char *sql);
1999
SQLITE_API int sqlite3_complete16(const void *sql);
2000
2001
/*
2002
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2003
**
2004
** ^This routine sets a callback function that might be invoked whenever
2005
** an attempt is made to open a database table that another thread
2006
** or process has locked.
2007
**
2008
** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
2009
** is returned immediately upon encountering the lock.  ^If the busy callback
2010
** is not NULL, then the callback might be invoked with two arguments.
2011
**
2012
** ^The first argument to the busy handler is a copy of the void* pointer which
2013
** is the third argument to sqlite3_busy_handler().  ^The second argument to
2014
** the busy handler callback is the number of times that the busy handler has
2015
** been invoked for this locking event.  ^If the
2016
** busy callback returns 0, then no additional attempts are made to
2017
** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
2018
** ^If the callback returns non-zero, then another attempt
2019
** is made to open the database for reading and the cycle repeats.
2020
**
2021
** The presence of a busy handler does not guarantee that it will be invoked
2022
** when there is lock contention. ^If SQLite determines that invoking the busy
2023
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2024
** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
2025
** Consider a scenario where one process is holding a read lock that
2026
** it is trying to promote to a reserved lock and
2027
** a second process is holding a reserved lock that it is trying
2028
** to promote to an exclusive lock.  The first process cannot proceed
2029
** because it is blocked by the second and the second process cannot
2030
** proceed because it is blocked by the first.  If both processes
2031
** invoke the busy handlers, neither will make any progress.  Therefore,
2032
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2033
** will induce the first process to release its read lock and allow
2034
** the second process to proceed.
2035
**
2036
** ^The default busy callback is NULL.
2037
**
2038
** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
2039
** when SQLite is in the middle of a large transaction where all the
2040
** changes will not fit into the in-memory cache.  SQLite will
2041
** already hold a RESERVED lock on the database file, but it needs
2042
** to promote this lock to EXCLUSIVE so that it can spill cache
2043
** pages into the database file without harm to concurrent
2044
** readers.  ^If it is unable to promote the lock, then the in-memory
2045
** cache will be left in an inconsistent state and so the error
2046
** code is promoted from the relatively benign [SQLITE_BUSY] to
2047
** the more severe [SQLITE_IOERR_BLOCKED].  ^This error code promotion
2048
** forces an automatic rollback of the changes.  See the
2049
** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
2050
** CorruptionFollowingBusyError</a> wiki page for a discussion of why
2051
** this is important.
2052
**
2053
** ^(There can only be a single busy handler defined for each
2054
** [database connection].  Setting a new busy handler clears any
2055
** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
2056
** will also set or clear the busy handler.
2057
**
2058
** The busy callback should not take any actions which modify the
2059
** database connection that invoked the busy handler.  Any such actions
2060
** result in undefined behavior.
2061
** 
2062
** A busy handler must not close the database connection
2063
** or [prepared statement] that invoked the busy handler.
2064
*/
2065
SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
2066
2067
/*
2068
** CAPI3REF: Set A Busy Timeout
2069
**
2070
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2071
** for a specified amount of time when a table is locked.  ^The handler
2072
** will sleep multiple times until at least "ms" milliseconds of sleeping
2073
** have accumulated.  ^After at least "ms" milliseconds of sleeping,
2074
** the handler returns 0 which causes [sqlite3_step()] to return
2075
** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
2076
**
2077
** ^Calling this routine with an argument less than or equal to zero
2078
** turns off all busy handlers.
2079
**
2080
** ^(There can only be a single busy handler for a particular
2081
** [database connection] any any given moment.  If another busy handler
2082
** was defined  (using [sqlite3_busy_handler()]) prior to calling
2083
** this routine, that other busy handler is cleared.)^
2084
*/
2085
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
2086
2087
/*
2088
** CAPI3REF: Convenience Routines For Running Queries
2089
**
2090
** This is a legacy interface that is preserved for backwards compatibility.
2091
** Use of this interface is not recommended.
2092
**
2093
** Definition: A <b>result table</b> is memory data structure created by the
2094
** [sqlite3_get_table()] interface.  A result table records the
2095
** complete query results from one or more queries.
2096
**
2097
** The table conceptually has a number of rows and columns.  But
2098
** these numbers are not part of the result table itself.  These
2099
** numbers are obtained separately.  Let N be the number of rows
2100
** and M be the number of columns.
2101
**
2102
** A result table is an array of pointers to zero-terminated UTF-8 strings.
2103
** There are (N+1)*M elements in the array.  The first M pointers point
2104
** to zero-terminated strings that  contain the names of the columns.
2105
** The remaining entries all point to query results.  NULL values result
2106
** in NULL pointers.  All other values are in their UTF-8 zero-terminated
2107
** string representation as returned by [sqlite3_column_text()].
2108
**
2109
** A result table might consist of one or more memory allocations.
2110
** It is not safe to pass a result table directly to [sqlite3_free()].
2111
** A result table should be deallocated using [sqlite3_free_table()].
2112
**
2113
** ^(As an example of the result table format, suppose a query result
2114
** is as follows:
2115
**
2116
** <blockquote><pre>
2117
**        Name        | Age
2118
**        -----------------------
2119
**        Alice       | 43
2120
**        Bob         | 28
2121
**        Cindy       | 21
2122
** </pre></blockquote>
2123
**
2124
** There are two column (M==2) and three rows (N==3).  Thus the
2125
** result table has 8 entries.  Suppose the result table is stored
2126
** in an array names azResult.  Then azResult holds this content:
2127
**
2128
** <blockquote><pre>
2129
**        azResult&#91;0] = "Name";
2130
**        azResult&#91;1] = "Age";
2131
**        azResult&#91;2] = "Alice";
2132
**        azResult&#91;3] = "43";
2133
**        azResult&#91;4] = "Bob";
2134
**        azResult&#91;5] = "28";
2135
**        azResult&#91;6] = "Cindy";
2136
**        azResult&#91;7] = "21";
2137
** </pre></blockquote>)^
2138
**
2139
** ^The sqlite3_get_table() function evaluates one or more
2140
** semicolon-separated SQL statements in the zero-terminated UTF-8
2141
** string of its 2nd parameter and returns a result table to the
2142
** pointer given in its 3rd parameter.
2143
**
2144
** After the application has finished with the result from sqlite3_get_table(),
2145
** it must pass the result table pointer to sqlite3_free_table() in order to
2146
** release the memory that was malloced.  Because of the way the
2147
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2148
** function must not try to call [sqlite3_free()] directly.  Only
2149
** [sqlite3_free_table()] is able to release the memory properly and safely.
2150
**
2151
** The sqlite3_get_table() interface is implemented as a wrapper around
2152
** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
2153
** to any internal data structures of SQLite.  It uses only the public
2154
** interface defined here.  As a consequence, errors that occur in the
2155
** wrapper layer outside of the internal [sqlite3_exec()] call are not
2156
** reflected in subsequent calls to [sqlite3_errcode()] or
2157
** [sqlite3_errmsg()].
2158
*/
2159
SQLITE_API int sqlite3_get_table(
2160
  sqlite3 *db,          /* An open database */
2161
  const char *zSql,     /* SQL to be evaluated */
2162
  char ***pazResult,    /* Results of the query */
2163
  int *pnRow,           /* Number of result rows written here */
2164
  int *pnColumn,        /* Number of result columns written here */
2165
  char **pzErrmsg       /* Error msg written here */
2166
);
2167
SQLITE_API void sqlite3_free_table(char **result);
2168
2169
/*
2170
** CAPI3REF: Formatted String Printing Functions
2171
**
2172
** These routines are work-alikes of the "printf()" family of functions
2173
** from the standard C library.
2174
**
2175
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2176
** results into memory obtained from [sqlite3_malloc()].
2177
** The strings returned by these two routines should be
2178
** released by [sqlite3_free()].  ^Both routines return a
2179
** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
2180
** memory to hold the resulting string.
2181
**
2182
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2183
** the standard C library.  The result is written into the
2184
** buffer supplied as the second parameter whose size is given by
2185
** the first parameter. Note that the order of the
2186
** first two parameters is reversed from snprintf().)^  This is an
2187
** historical accident that cannot be fixed without breaking
2188
** backwards compatibility.  ^(Note also that sqlite3_snprintf()
2189
** returns a pointer to its buffer instead of the number of
2190
** characters actually written into the buffer.)^  We admit that
2191
** the number of characters written would be a more useful return
2192
** value but we cannot change the implementation of sqlite3_snprintf()
2193
** now without breaking compatibility.
2194
**
2195
** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2196
** guarantees that the buffer is always zero-terminated.  ^The first
2197
** parameter "n" is the total size of the buffer, including space for
2198
** the zero terminator.  So the longest string that can be completely
2199
** written will be n-1 characters.
2200
**
2201
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2202
**
2203
** These routines all implement some additional formatting
2204
** options that are useful for constructing SQL statements.
2205
** All of the usual printf() formatting options apply.  In addition, there
2206
** is are "%q", "%Q", and "%z" options.
2207
**
2208
** ^(The %q option works like %s in that it substitutes a nul-terminated
2209
** string from the argument list.  But %q also doubles every '\'' character.
2210
** %q is designed for use inside a string literal.)^  By doubling each '\''
2211
** character it escapes that character and allows it to be inserted into
2212
** the string.
2213
**
2214
** For example, assume the string variable zText contains text as follows:
2215
**
2216
** <blockquote><pre>
2217
**  char *zText = "It's a happy day!";
2218
** </pre></blockquote>
2219
**
2220
** One can use this text in an SQL statement as follows:
2221
**
2222
** <blockquote><pre>
2223
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
2224
**  sqlite3_exec(db, zSQL, 0, 0, 0);
2225
**  sqlite3_free(zSQL);
2226
** </pre></blockquote>
2227
**
2228
** Because the %q format string is used, the '\'' character in zText
2229
** is escaped and the SQL generated is as follows:
2230
**
2231
** <blockquote><pre>
2232
**  INSERT INTO table1 VALUES('It''s a happy day!')
2233
** </pre></blockquote>
2234
**
2235
** This is correct.  Had we used %s instead of %q, the generated SQL
2236
** would have looked like this:
2237
**
2238
** <blockquote><pre>
2239
**  INSERT INTO table1 VALUES('It's a happy day!');
2240
** </pre></blockquote>
2241
**
2242
** This second example is an SQL syntax error.  As a general rule you should
2243
** always use %q instead of %s when inserting text into a string literal.
2244
**
2245
** ^(The %Q option works like %q except it also adds single quotes around
2246
** the outside of the total string.  Additionally, if the parameter in the
2247
** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
2248
** single quotes).)^  So, for example, one could say:
2249
**
2250
** <blockquote><pre>
2251
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
2252
**  sqlite3_exec(db, zSQL, 0, 0, 0);
2253
**  sqlite3_free(zSQL);
2254
** </pre></blockquote>
2255
**
2256
** The code above will render a correct SQL statement in the zSQL
2257
** variable even if the zText variable is a NULL pointer.
2258
**
2259
** ^(The "%z" formatting option works like "%s" but with the
2260
** addition that after the string has been read and copied into
2261
** the result, [sqlite3_free()] is called on the input string.)^
2262
*/
2263
SQLITE_API char *sqlite3_mprintf(const char*,...);
2264
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
2265
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
2266
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
2267
2268
/*
2269
** CAPI3REF: Memory Allocation Subsystem
2270
**
2271
** The SQLite core uses these three routines for all of its own
2272
** internal memory allocation needs. "Core" in the previous sentence
2273
** does not include operating-system specific VFS implementation.  The
2274
** Windows VFS uses native malloc() and free() for some operations.
2275
**
2276
** ^The sqlite3_malloc() routine returns a pointer to a block
2277
** of memory at least N bytes in length, where N is the parameter.
2278
** ^If sqlite3_malloc() is unable to obtain sufficient free
2279
** memory, it returns a NULL pointer.  ^If the parameter N to
2280
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2281
** a NULL pointer.
2282
**
2283
** ^Calling sqlite3_free() with a pointer previously returned
2284
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2285
** that it might be reused.  ^The sqlite3_free() routine is
2286
** a no-op if is called with a NULL pointer.  Passing a NULL pointer
2287
** to sqlite3_free() is harmless.  After being freed, memory
2288
** should neither be read nor written.  Even reading previously freed
2289
** memory might result in a segmentation fault or other severe error.
2290
** Memory corruption, a segmentation fault, or other severe error
2291
** might result if sqlite3_free() is called with a non-NULL pointer that
2292
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2293
**
2294
** ^(The sqlite3_realloc() interface attempts to resize a
2295
** prior memory allocation to be at least N bytes, where N is the
2296
** second parameter.  The memory allocation to be resized is the first
2297
** parameter.)^ ^ If the first parameter to sqlite3_realloc()
2298
** is a NULL pointer then its behavior is identical to calling
2299
** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
2300
** ^If the second parameter to sqlite3_realloc() is zero or
2301
** negative then the behavior is exactly the same as calling
2302
** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
2303
** ^sqlite3_realloc() returns a pointer to a memory allocation
2304
** of at least N bytes in size or NULL if sufficient memory is unavailable.
2305
** ^If M is the size of the prior allocation, then min(N,M) bytes
2306
** of the prior allocation are copied into the beginning of buffer returned
2307
** by sqlite3_realloc() and the prior allocation is freed.
2308
** ^If sqlite3_realloc() returns NULL, then the prior allocation
2309
** is not freed.
2310
**
2311
** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
2312
** is always aligned to at least an 8 byte boundary, or to a
2313
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2314
** option is used.
2315
**
2316
** In SQLite version 3.5.0 and 3.5.1, it was possible to define
2317
** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
2318
** implementation of these routines to be omitted.  That capability
2319
** is no longer provided.  Only built-in memory allocators can be used.
2320
**
2321
** Prior to SQLite version 3.7.10, the Windows OS interface layer called
2322
** the system malloc() and free() directly when converting
2323
** filenames between the UTF-8 encoding used by SQLite
2324
** and whatever filename encoding is used by the particular Windows
2325
** installation.  Memory allocation errors were detected, but
2326
** they were reported back as [SQLITE_CANTOPEN] or
2327
** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
2328
**
2329
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2330
** must be either NULL or else pointers obtained from a prior
2331
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2332
** not yet been released.
2333
**
2334
** The application must not read or write any part of
2335
** a block of memory after it has been released using
2336
** [sqlite3_free()] or [sqlite3_realloc()].
2337
*/
2338
SQLITE_API void *sqlite3_malloc(int);
2339
SQLITE_API void *sqlite3_realloc(void*, int);
2340
SQLITE_API void sqlite3_free(void*);
2341
2342
/*
2343
** CAPI3REF: Memory Allocator Statistics
2344
**
2345
** SQLite provides these two interfaces for reporting on the status
2346
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2347
** routines, which form the built-in memory allocation subsystem.
2348
**
2349
** ^The [sqlite3_memory_used()] routine returns the number of bytes
2350
** of memory currently outstanding (malloced but not freed).
2351
** ^The [sqlite3_memory_highwater()] routine returns the maximum
2352
** value of [sqlite3_memory_used()] since the high-water mark
2353
** was last reset.  ^The values returned by [sqlite3_memory_used()] and
2354
** [sqlite3_memory_highwater()] include any overhead
2355
** added by SQLite in its implementation of [sqlite3_malloc()],
2356
** but not overhead added by the any underlying system library
2357
** routines that [sqlite3_malloc()] may call.
2358
**
2359
** ^The memory high-water mark is reset to the current value of
2360
** [sqlite3_memory_used()] if and only if the parameter to
2361
** [sqlite3_memory_highwater()] is true.  ^The value returned
2362
** by [sqlite3_memory_highwater(1)] is the high-water mark
2363
** prior to the reset.
2364
*/
2365
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
2366
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
2367
2368
/*
2369
** CAPI3REF: Pseudo-Random Number Generator
2370
**
2371
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
2372
** select random [ROWID | ROWIDs] when inserting new records into a table that
2373
** already uses the largest possible [ROWID].  The PRNG is also used for
2374
** the build-in random() and randomblob() SQL functions.  This interface allows
2375
** applications to access the same PRNG for other purposes.
2376
**
2377
** ^A call to this routine stores N bytes of randomness into buffer P.
2378
**
2379
** ^The first time this routine is invoked (either internally or by
2380
** the application) the PRNG is seeded using randomness obtained
2381
** from the xRandomness method of the default [sqlite3_vfs] object.
2382
** ^On all subsequent invocations, the pseudo-randomness is generated
2383
** internally and without recourse to the [sqlite3_vfs] xRandomness
2384
** method.
2385
*/
2386
SQLITE_API void sqlite3_randomness(int N, void *P);
2387
2388
/*
2389
** CAPI3REF: Compile-Time Authorization Callbacks
2390
**
2391
** ^This routine registers an authorizer callback with a particular
2392
** [database connection], supplied in the first argument.
2393
** ^The authorizer callback is invoked as SQL statements are being compiled
2394
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
2395
** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  ^At various
2396
** points during the compilation process, as logic is being created
2397
** to perform various actions, the authorizer callback is invoked to
2398
** see if those actions are allowed.  ^The authorizer callback should
2399
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
2400
** specific action but allow the SQL statement to continue to be
2401
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2402
** rejected with an error.  ^If the authorizer callback returns
2403
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2404
** then the [sqlite3_prepare_v2()] or equivalent call that triggered
2405
** the authorizer will fail with an error message.
2406
**
2407
** When the callback returns [SQLITE_OK], that means the operation
2408
** requested is ok.  ^When the callback returns [SQLITE_DENY], the
2409
** [sqlite3_prepare_v2()] or equivalent call that triggered the
2410
** authorizer will fail with an error message explaining that
2411
** access is denied. 
2412
**
2413
** ^The first parameter to the authorizer callback is a copy of the third
2414
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
2415
** to the callback is an integer [SQLITE_COPY | action code] that specifies
2416
** the particular action to be authorized. ^The third through sixth parameters
2417
** to the callback are zero-terminated strings that contain additional
2418
** details about the action to be authorized.
2419
**
2420
** ^If the action code is [SQLITE_READ]
2421
** and the callback returns [SQLITE_IGNORE] then the
2422
** [prepared statement] statement is constructed to substitute
2423
** a NULL value in place of the table column that would have
2424
** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
2425
** return can be used to deny an untrusted user access to individual
2426
** columns of a table.
2427
** ^If the action code is [SQLITE_DELETE] and the callback returns
2428
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2429
** [truncate optimization] is disabled and all rows are deleted individually.
2430
**
2431
** An authorizer is used when [sqlite3_prepare | preparing]
2432
** SQL statements from an untrusted source, to ensure that the SQL statements
2433
** do not try to access data they are not allowed to see, or that they do not
2434
** try to execute malicious statements that damage the database.  For
2435
** example, an application may allow a user to enter arbitrary
2436
** SQL queries for evaluation by a database.  But the application does
2437
** not want the user to be able to make arbitrary changes to the
2438
** database.  An authorizer could then be put in place while the
2439
** user-entered SQL is being [sqlite3_prepare | prepared] that
2440
** disallows everything except [SELECT] statements.
2441
**
2442
** Applications that need to process SQL from untrusted sources
2443
** might also consider lowering resource limits using [sqlite3_limit()]
2444
** and limiting database size using the [max_page_count] [PRAGMA]
2445
** in addition to using an authorizer.
2446
**
2447
** ^(Only a single authorizer can be in place on a database connection
2448
** at a time.  Each call to sqlite3_set_authorizer overrides the
2449
** previous call.)^  ^Disable the authorizer by installing a NULL callback.
2450
** The authorizer is disabled by default.
2451
**
2452
** The authorizer callback must not do anything that will modify
2453
** the database connection that invoked the authorizer callback.
2454
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2455
** database connections for the meaning of "modify" in this paragraph.
2456
**
2457
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
2458
** statement might be re-prepared during [sqlite3_step()] due to a 
2459
** schema change.  Hence, the application should ensure that the
2460
** correct authorizer callback remains in place during the [sqlite3_step()].
2461
**
2462
** ^Note that the authorizer callback is invoked only during
2463
** [sqlite3_prepare()] or its variants.  Authorization is not
2464
** performed during statement evaluation in [sqlite3_step()], unless
2465
** as stated in the previous paragraph, sqlite3_step() invokes
2466
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
2467
*/
2468
SQLITE_API int sqlite3_set_authorizer(
2469
  sqlite3*,
2470
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
2471
  void *pUserData
2472
);
2473
2474
/*
2475
** CAPI3REF: Authorizer Return Codes
2476
**
2477
** The [sqlite3_set_authorizer | authorizer callback function] must
2478
** return either [SQLITE_OK] or one of these two constants in order
2479
** to signal SQLite whether or not the action is permitted.  See the
2480
** [sqlite3_set_authorizer | authorizer documentation] for additional
2481
** information.
2482
**
2483
** Note that SQLITE_IGNORE is also used as a [SQLITE_ROLLBACK | return code]
2484
** from the [sqlite3_vtab_on_conflict()] interface.
2485
*/
2486
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
2487
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
2488
2489
/*
2490
** CAPI3REF: Authorizer Action Codes
2491
**
2492
** The [sqlite3_set_authorizer()] interface registers a callback function
2493
** that is invoked to authorize certain SQL statement actions.  The
2494
** second parameter to the callback is an integer code that specifies
2495
** what action is being authorized.  These are the integer action codes that
2496
** the authorizer callback may be passed.
2497
**
2498
** These action code values signify what kind of operation is to be
2499
** authorized.  The 3rd and 4th parameters to the authorization
2500
** callback function will be parameters or NULL depending on which of these
2501
** codes is used as the second parameter.  ^(The 5th parameter to the
2502
** authorizer callback is the name of the database ("main", "temp",
2503
** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
2504
** is the name of the inner-most trigger or view that is responsible for
2505
** the access attempt or NULL if this access attempt is directly from
2506
** top-level SQL code.
2507
*/
2508
/******************************************* 3rd ************ 4th ***********/
2509
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
2510
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
2511
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
2512
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
2513
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
2514
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
2515
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
2516
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
2517
#define SQLITE_DELETE                9   /* Table Name      NULL            */
2518
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
2519
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
2520
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
2521
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
2522
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
2523
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
2524
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
2525
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
2526
#define SQLITE_INSERT               18   /* Table Name      NULL            */
2527
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
2528
#define SQLITE_READ                 20   /* Table Name      Column Name     */
2529
#define SQLITE_SELECT               21   /* NULL            NULL            */
2530
#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
2531
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
2532
#define SQLITE_ATTACH               24   /* Filename        NULL            */
2533
#define SQLITE_DETACH               25   /* Database Name   NULL            */
2534
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
2535
#define SQLITE_REINDEX              27   /* Index Name      NULL            */
2536
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
2537
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
2538
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
2539
#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
2540
#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
2541
#define SQLITE_COPY                  0   /* No longer used */
2542
2543
/*
2544
** CAPI3REF: Tracing And Profiling Functions
2545
**
2546
** These routines register callback functions that can be used for
2547
** tracing and profiling the execution of SQL statements.
2548
**
2549
** ^The callback function registered by sqlite3_trace() is invoked at
2550
** various times when an SQL statement is being run by [sqlite3_step()].
2551
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2552
** SQL statement text as the statement first begins executing.
2553
** ^(Additional sqlite3_trace() callbacks might occur
2554
** as each triggered subprogram is entered.  The callbacks for triggers
2555
** contain a UTF-8 SQL comment that identifies the trigger.)^
2556
**
2557
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
2558
** the length of [bound parameter] expansion in the output of sqlite3_trace().
2559
**
2560
** ^The callback function registered by sqlite3_profile() is invoked
2561
** as each SQL statement finishes.  ^The profile callback contains
2562
** the original statement text and an estimate of wall-clock time
2563
** of how long that statement took to run.  ^The profile callback
2564
** time is in units of nanoseconds, however the current implementation
2565
** is only capable of millisecond resolution so the six least significant
2566
** digits in the time are meaningless.  Future versions of SQLite
2567
** might provide greater resolution on the profiler callback.  The
2568
** sqlite3_profile() function is considered experimental and is
2569
** subject to change in future versions of SQLite.
2570
*/
2571
SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
2572
SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
2573
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
2574
2575
/*
2576
** CAPI3REF: Query Progress Callbacks
2577
**
2578
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
2579
** function X to be invoked periodically during long running calls to
2580
** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
2581
** database connection D.  An example use for this
2582
** interface is to keep a GUI updated during a large query.
2583
**
2584
** ^The parameter P is passed through as the only parameter to the 
2585
** callback function X.  ^The parameter N is the approximate number of 
2586
** [virtual machine instructions] that are evaluated between successive
2587
** invocations of the callback X.  ^If N is less than one then the progress
2588
** handler is disabled.
2589
**
2590
** ^Only a single progress handler may be defined at one time per
2591
** [database connection]; setting a new progress handler cancels the
2592
** old one.  ^Setting parameter X to NULL disables the progress handler.
2593
** ^The progress handler is also disabled by setting N to a value less
2594
** than 1.
2595
**
2596
** ^If the progress callback returns non-zero, the operation is
2597
** interrupted.  This feature can be used to implement a
2598
** "Cancel" button on a GUI progress dialog box.
2599
**
2600
** The progress handler callback must not do anything that will modify
2601
** the database connection that invoked the progress handler.
2602
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2603
** database connections for the meaning of "modify" in this paragraph.
2604
**
2605
*/
2606
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
2607
2608
/*
2609
** CAPI3REF: Opening A New Database Connection
2610
**
2611
** ^These routines open an SQLite database file as specified by the 
2612
** filename argument. ^The filename argument is interpreted as UTF-8 for
2613
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
2614
** order for sqlite3_open16(). ^(A [database connection] handle is usually
2615
** returned in *ppDb, even if an error occurs.  The only exception is that
2616
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
2617
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
2618
** object.)^ ^(If the database is opened (and/or created) successfully, then
2619
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
2620
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
2621
** an English language description of the error following a failure of any
2622
** of the sqlite3_open() routines.
2623
**
2624
** ^The default encoding for the database will be UTF-8 if
2625
** sqlite3_open() or sqlite3_open_v2() is called and
2626
** UTF-16 in the native byte order if sqlite3_open16() is used.
2627
**
2628
** Whether or not an error occurs when it is opened, resources
2629
** associated with the [database connection] handle should be released by
2630
** passing it to [sqlite3_close()] when it is no longer required.
2631
**
2632
** The sqlite3_open_v2() interface works like sqlite3_open()
2633
** except that it accepts two additional parameters for additional control
2634
** over the new database connection.  ^(The flags parameter to
2635
** sqlite3_open_v2() can take one of
2636
** the following three values, optionally combined with the 
2637
** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
2638
** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
2639
**
2640
** <dl>
2641
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
2642
** <dd>The database is opened in read-only mode.  If the database does not
2643
** already exist, an error is returned.</dd>)^
2644
**
2645
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
2646
** <dd>The database is opened for reading and writing if possible, or reading
2647
** only if the file is write protected by the operating system.  In either
2648
** case the database must already exist, otherwise an error is returned.</dd>)^
2649
**
2650
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
2651
** <dd>The database is opened for reading and writing, and is created if
2652
** it does not already exist. This is the behavior that is always used for
2653
** sqlite3_open() and sqlite3_open16().</dd>)^
2654
** </dl>
2655
**
2656
** If the 3rd parameter to sqlite3_open_v2() is not one of the
2657
** combinations shown above optionally combined with other
2658
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
2659
** then the behavior is undefined.
2660
**
2661
** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
2662
** opens in the multi-thread [threading mode] as long as the single-thread
2663
** mode has not been set at compile-time or start-time.  ^If the
2664
** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
2665
** in the serialized [threading mode] unless single-thread was
2666
** previously selected at compile-time or start-time.
2667
** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
2668
** eligible to use [shared cache mode], regardless of whether or not shared
2669
** cache is enabled using [sqlite3_enable_shared_cache()].  ^The
2670
** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
2671
** participate in [shared cache mode] even if it is enabled.
2672
**
2673
** ^The fourth parameter to sqlite3_open_v2() is the name of the
2674
** [sqlite3_vfs] object that defines the operating system interface that
2675
** the new database connection should use.  ^If the fourth parameter is
2676
** a NULL pointer then the default [sqlite3_vfs] object is used.
2677
**
2678
** ^If the filename is ":memory:", then a private, temporary in-memory database
2679
** is created for the connection.  ^This in-memory database will vanish when
2680
** the database connection is closed.  Future versions of SQLite might
2681
** make use of additional special filenames that begin with the ":" character.
2682
** It is recommended that when a database filename actually does begin with
2683
** a ":" character you should prefix the filename with a pathname such as
2684
** "./" to avoid ambiguity.
2685
**
2686
** ^If the filename is an empty string, then a private, temporary
2687
** on-disk database will be created.  ^This private database will be
2688
** automatically deleted as soon as the database connection is closed.
2689
**
2690
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
2691
**
2692
** ^If [URI filename] interpretation is enabled, and the filename argument
2693
** begins with "file:", then the filename is interpreted as a URI. ^URI
2694
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
2695
** set in the fourth argument to sqlite3_open_v2(), or if it has
2696
** been enabled globally using the [SQLITE_CONFIG_URI] option with the
2697
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
2698
** As of SQLite version 3.7.7, URI filename interpretation is turned off
2699
** by default, but future releases of SQLite might enable URI filename
2700
** interpretation by default.  See "[URI filenames]" for additional
2701
** information.
2702
**
2703
** URI filenames are parsed according to RFC 3986. ^If the URI contains an
2704
** authority, then it must be either an empty string or the string 
2705
** "localhost". ^If the authority is not an empty string or "localhost", an 
2706
** error is returned to the caller. ^The fragment component of a URI, if 
2707
** present, is ignored.
2708
**
2709
** ^SQLite uses the path component of the URI as the name of the disk file
2710
** which contains the database. ^If the path begins with a '/' character, 
2711
** then it is interpreted as an absolute path. ^If the path does not begin 
2712
** with a '/' (meaning that the authority section is omitted from the URI)
2713
** then the path is interpreted as a relative path. 
2714
** ^On windows, the first component of an absolute path 
2715
** is a drive specification (e.g. "C:").
2716
**
2717
** [[core URI query parameters]]
2718
** The query component of a URI may contain parameters that are interpreted
2719
** either by SQLite itself, or by a [VFS | custom VFS implementation].
2720
** SQLite interprets the following three query parameters:
2721
**
2722
** <ul>
2723
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
2724
**     a VFS object that provides the operating system interface that should
2725
**     be used to access the database file on disk. ^If this option is set to
2726
**     an empty string the default VFS object is used. ^Specifying an unknown
2727
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
2728
**     present, then the VFS specified by the option takes precedence over
2729
**     the value passed as the fourth parameter to sqlite3_open_v2().
2730
**
2731
**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
2732
**     "rwc", or "memory". Attempting to set it to any other value is
2733
**     an error)^. 
2734
**     ^If "ro" is specified, then the database is opened for read-only 
2735
**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 
2736
**     third argument to sqlite3_open_v2(). ^If the mode option is set to 
2737
**     "rw", then the database is opened for read-write (but not create) 
2738
**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 
2739
**     been set. ^Value "rwc" is equivalent to setting both 
2740
**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
2741
**     set to "memory" then a pure [in-memory database] that never reads
2742
**     or writes from disk is used. ^It is an error to specify a value for
2743
**     the mode parameter that is less restrictive than that specified by
2744
**     the flags passed in the third parameter to sqlite3_open_v2().
2745
**
2746
**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
2747
**     "private". ^Setting it to "shared" is equivalent to setting the
2748
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
2749
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
2750
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
2751
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
2752
**     a URI filename, its value overrides any behavior requested by setting
2753
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
2754
** </ul>
2755
**
2756
** ^Specifying an unknown parameter in the query component of a URI is not an
2757
** error.  Future versions of SQLite might understand additional query
2758
** parameters.  See "[query parameters with special meaning to SQLite]" for
2759
** additional information.
2760
**
2761
** [[URI filename examples]] <h3>URI filename examples</h3>
2762
**
2763
** <table border="1" align=center cellpadding=5>
2764
** <tr><th> URI filenames <th> Results
2765
** <tr><td> file:data.db <td> 
2766
**          Open the file "data.db" in the current directory.
2767
** <tr><td> file:/home/fred/data.db<br>
2768
**          file:///home/fred/data.db <br> 
2769
**          file://localhost/home/fred/data.db <br> <td> 
2770
**          Open the database file "/home/fred/data.db".
2771
** <tr><td> file://darkstar/home/fred/data.db <td> 
2772
**          An error. "darkstar" is not a recognized authority.
2773
** <tr><td style="white-space:nowrap"> 
2774
**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
2775
**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
2776
**          C:. Note that the %20 escaping in this example is not strictly 
2777
**          necessary - space characters can be used literally
2778
**          in URI filenames.
2779
** <tr><td> file:data.db?mode=ro&cache=private <td> 
2780
**          Open file "data.db" in the current directory for read-only access.
2781
**          Regardless of whether or not shared-cache mode is enabled by
2782
**          default, use a private cache.
2783
** <tr><td> file:/home/fred/data.db?vfs=unix-nolock <td>
2784
**          Open file "/home/fred/data.db". Use the special VFS "unix-nolock".
2785
** <tr><td> file:data.db?mode=readonly <td> 
2786
**          An error. "readonly" is not a valid option for the "mode" parameter.
2787
** </table>
2788
**
2789
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
2790
** query components of a URI. A hexadecimal escape sequence consists of a
2791
** percent sign - "%" - followed by exactly two hexadecimal digits 
2792
** specifying an octet value. ^Before the path or query components of a
2793
** URI filename are interpreted, they are encoded using UTF-8 and all 
2794
** hexadecimal escape sequences replaced by a single byte containing the
2795
** corresponding octet. If this process generates an invalid UTF-8 encoding,
2796
** the results are undefined.
2797
**
2798
** <b>Note to Windows users:</b>  The encoding used for the filename argument
2799
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
2800
** codepage is currently defined.  Filenames containing international
2801
** characters must be converted to UTF-8 prior to passing them into
2802
** sqlite3_open() or sqlite3_open_v2().
2803
**
2804
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
2805
** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
2806
** features that require the use of temporary files may fail.
2807
**
2808
** See also: [sqlite3_temp_directory]
2809
*/
2810
SQLITE_API int sqlite3_open(
2811
  const char *filename,   /* Database filename (UTF-8) */
2812
  sqlite3 **ppDb          /* OUT: SQLite db handle */
2813
);
2814
SQLITE_API int sqlite3_open16(
2815
  const void *filename,   /* Database filename (UTF-16) */
2816
  sqlite3 **ppDb          /* OUT: SQLite db handle */
2817
);
2818
SQLITE_API int sqlite3_open_v2(
2819
  const char *filename,   /* Database filename (UTF-8) */
2820
  sqlite3 **ppDb,         /* OUT: SQLite db handle */
2821
  int flags,              /* Flags */
2822
  const char *zVfs        /* Name of VFS module to use */
2823
);
2824
2825
/*
2826
** CAPI3REF: Obtain Values For URI Parameters
2827
**
2828
** These are utility routines, useful to VFS implementations, that check
2829
** to see if a database file was a URI that contained a specific query 
2830
** parameter, and if so obtains the value of that query parameter.
2831
**
2832
** If F is the database filename pointer passed into the xOpen() method of 
2833
** a VFS implementation when the flags parameter to xOpen() has one or 
2834
** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
2835
** P is the name of the query parameter, then
2836
** sqlite3_uri_parameter(F,P) returns the value of the P
2837
** parameter if it exists or a NULL pointer if P does not appear as a 
2838
** query parameter on F.  If P is a query parameter of F
2839
** has no explicit value, then sqlite3_uri_parameter(F,P) returns
2840
** a pointer to an empty string.
2841
**
2842
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
2843
** parameter and returns true (1) or false (0) according to the value
2844
** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
2845
** value of query parameter P is one of "yes", "true", or "on" in any
2846
** case or if the value begins with a non-zero number.  The 
2847
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
2848
** query parameter P is one of "no", "false", or "off" in any case or
2849
** if the value begins with a numeric zero.  If P is not a query
2850
** parameter on F or if the value of P is does not match any of the
2851
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
2852
**
2853
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
2854
** 64-bit signed integer and returns that integer, or D if P does not
2855
** exist.  If the value of P is something other than an integer, then
2856
** zero is returned.
2857
** 
2858
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
2859
** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
2860
** is not a database file pathname pointer that SQLite passed into the xOpen
2861
** VFS method, then the behavior of this routine is undefined and probably
2862
** undesirable.
2863
*/
2864
SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
2865
SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
2866
SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
2867
2868
2869
/*
2870
** CAPI3REF: Error Codes And Messages
2871
**
2872
** ^The sqlite3_errcode() interface returns the numeric [result code] or
2873
** [extended result code] for the most recent failed sqlite3_* API call
2874
** associated with a [database connection]. If a prior API call failed
2875
** but the most recent API call succeeded, the return value from
2876
** sqlite3_errcode() is undefined.  ^The sqlite3_extended_errcode()
2877
** interface is the same except that it always returns the 
2878
** [extended result code] even when extended result codes are
2879
** disabled.
2880
**
2881
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
2882
** text that describes the error, as either UTF-8 or UTF-16 respectively.
2883
** ^(Memory to hold the error message string is managed internally.
2884
** The application does not need to worry about freeing the result.
2885
** However, the error string might be overwritten or deallocated by
2886
** subsequent calls to other SQLite interface functions.)^
2887
**
2888
** ^The sqlite3_errstr() interface returns the English-language text
2889
** that describes the [result code], as UTF-8.
2890
** ^(Memory to hold the error message string is managed internally
2891
** and must not be freed by the application)^.
2892
**
2893
** When the serialized [threading mode] is in use, it might be the
2894
** case that a second error occurs on a separate thread in between
2895
** the time of the first error and the call to these interfaces.
2896
** When that happens, the second error will be reported since these
2897
** interfaces always report the most recent result.  To avoid
2898
** this, each thread can obtain exclusive use of the [database connection] D
2899
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
2900
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
2901
** all calls to the interfaces listed here are completed.
2902
**
2903
** If an interface fails with SQLITE_MISUSE, that means the interface
2904
** was invoked incorrectly by the application.  In that case, the
2905
** error code and message may or may not be set.
2906
*/
2907
SQLITE_API int sqlite3_errcode(sqlite3 *db);
2908
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
2909
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
2910
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
2911
SQLITE_API const char *sqlite3_errstr(int);
2912
2913
/*
2914
** CAPI3REF: SQL Statement Object
2915
** KEYWORDS: {prepared statement} {prepared statements}
2916
**
2917
** An instance of this object represents a single SQL statement.
2918
** This object is variously known as a "prepared statement" or a
2919
** "compiled SQL statement" or simply as a "statement".
2920
**
2921
** The life of a statement object goes something like this:
2922
**
2923
** <ol>
2924
** <li> Create the object using [sqlite3_prepare_v2()] or a related
2925
**      function.
2926
** <li> Bind values to [host parameters] using the sqlite3_bind_*()
2927
**      interfaces.
2928
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
2929
** <li> Reset the statement using [sqlite3_reset()] then go back
2930
**      to step 2.  Do this zero or more times.
2931
** <li> Destroy the object using [sqlite3_finalize()].
2932
** </ol>
2933
**
2934
** Refer to documentation on individual methods above for additional
2935
** information.
2936
*/
2937
typedef struct sqlite3_stmt sqlite3_stmt;
2938
2939
/*
2940
** CAPI3REF: Run-time Limits
2941
**
2942
** ^(This interface allows the size of various constructs to be limited
2943
** on a connection by connection basis.  The first parameter is the
2944
** [database connection] whose limit is to be set or queried.  The
2945
** second parameter is one of the [limit categories] that define a
2946
** class of constructs to be size limited.  The third parameter is the
2947
** new limit for that construct.)^
2948
**
2949
** ^If the new limit is a negative number, the limit is unchanged.
2950
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 
2951
** [limits | hard upper bound]
2952
** set at compile-time by a C preprocessor macro called
2953
** [limits | SQLITE_MAX_<i>NAME</i>].
2954
** (The "_LIMIT_" in the name is changed to "_MAX_".))^
2955
** ^Attempts to increase a limit above its hard upper bound are
2956
** silently truncated to the hard upper bound.
2957
**
2958
** ^Regardless of whether or not the limit was changed, the 
2959
** [sqlite3_limit()] interface returns the prior value of the limit.
2960
** ^Hence, to find the current value of a limit without changing it,
2961
** simply invoke this interface with the third parameter set to -1.
2962
**
2963
** Run-time limits are intended for use in applications that manage
2964
** both their own internal database and also databases that are controlled
2965
** by untrusted external sources.  An example application might be a
2966
** web browser that has its own databases for storing history and
2967
** separate databases controlled by JavaScript applications downloaded
2968
** off the Internet.  The internal databases can be given the
2969
** large, default limits.  Databases managed by external sources can
2970
** be given much smaller limits designed to prevent a denial of service
2971
** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
2972
** interface to further control untrusted SQL.  The size of the database
2973
** created by an untrusted script can be contained using the
2974
** [max_page_count] [PRAGMA].
2975
**
2976
** New run-time limit categories may be added in future releases.
2977
*/
2978
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
2979
2980
/*
2981
** CAPI3REF: Run-Time Limit Categories
2982
** KEYWORDS: {limit category} {*limit categories}
2983
**
2984
** These constants define various performance limits
2985
** that can be lowered at run-time using [sqlite3_limit()].
2986
** The synopsis of the meanings of the various limits is shown below.
2987
** Additional information is available at [limits | Limits in SQLite].
2988
**
2989
** <dl>
2990
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
2991
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
2992
**
2993
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
2994
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
2995
**
2996
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
2997
** <dd>The maximum number of columns in a table definition or in the
2998
** result set of a [SELECT] or the maximum number of columns in an index
2999
** or in an ORDER BY or GROUP BY clause.</dd>)^
3000
**
3001
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3002
** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3003
**
3004
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3005
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3006
**
3007
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3008
** <dd>The maximum number of instructions in a virtual machine program
3009
** used to implement an SQL statement.  This limit is not currently
3010
** enforced, though that might be added in some future release of
3011
** SQLite.</dd>)^
3012
**
3013
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3014
** <dd>The maximum number of arguments on a function.</dd>)^
3015
**
3016
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3017
** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3018
**
3019
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3020
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3021
** <dd>The maximum length of the pattern argument to the [LIKE] or
3022
** [GLOB] operators.</dd>)^
3023
**
3024
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3025
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3026
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3027
**
3028
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3029
** <dd>The maximum depth of recursion for triggers.</dd>)^
3030
** </dl>
3031
*/
3032
#define SQLITE_LIMIT_LENGTH                    0
3033
#define SQLITE_LIMIT_SQL_LENGTH                1
3034
#define SQLITE_LIMIT_COLUMN                    2
3035
#define SQLITE_LIMIT_EXPR_DEPTH                3
3036
#define SQLITE_LIMIT_COMPOUND_SELECT           4
3037
#define SQLITE_LIMIT_VDBE_OP                   5
3038
#define SQLITE_LIMIT_FUNCTION_ARG              6
3039
#define SQLITE_LIMIT_ATTACHED                  7
3040
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
3041
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
3042
#define SQLITE_LIMIT_TRIGGER_DEPTH            10
3043
3044
/*
3045
** CAPI3REF: Compiling An SQL Statement
3046
** KEYWORDS: {SQL statement compiler}
3047
**
3048
** To execute an SQL query, it must first be compiled into a byte-code
3049
** program using one of these routines.
3050
**
3051
** The first argument, "db", is a [database connection] obtained from a
3052
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
3053
** [sqlite3_open16()].  The database connection must not have been closed.
3054
**
3055
** The second argument, "zSql", is the statement to be compiled, encoded
3056
** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
3057
** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
3058
** use UTF-16.
3059
**
3060
** ^If the nByte argument is less than zero, then zSql is read up to the
3061
** first zero terminator. ^If nByte is non-negative, then it is the maximum
3062
** number of  bytes read from zSql.  ^When nByte is non-negative, the
3063
** zSql string ends at either the first '\000' or '\u0000' character or
3064
** the nByte-th byte, whichever comes first. If the caller knows
3065
** that the supplied string is nul-terminated, then there is a small
3066
** performance advantage to be gained by passing an nByte parameter that
3067
** is equal to the number of bytes in the input string <i>including</i>
3068
** the nul-terminator bytes as this saves SQLite from having to
3069
** make a copy of the input string.
3070
**
3071
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
3072
** past the end of the first SQL statement in zSql.  These routines only
3073
** compile the first statement in zSql, so *pzTail is left pointing to
3074
** what remains uncompiled.
3075
**
3076
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
3077
** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
3078
** to NULL.  ^If the input text contains no SQL (if the input is an empty
3079
** string or a comment) then *ppStmt is set to NULL.
3080
** The calling procedure is responsible for deleting the compiled
3081
** SQL statement using [sqlite3_finalize()] after it has finished with it.
3082
** ppStmt may not be NULL.
3083
**
3084
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
3085
** otherwise an [error code] is returned.
3086
**
3087
** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
3088
** recommended for all new programs. The two older interfaces are retained
3089
** for backwards compatibility, but their use is discouraged.
3090
** ^In the "v2" interfaces, the prepared statement
3091
** that is returned (the [sqlite3_stmt] object) contains a copy of the
3092
** original SQL text. This causes the [sqlite3_step()] interface to
3093
** behave differently in three ways:
3094
**
3095
** <ol>
3096
** <li>
3097
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
3098
** always used to do, [sqlite3_step()] will automatically recompile the SQL
3099
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
3100
** retries will occur before sqlite3_step() gives up and returns an error.
3101
** </li>
3102
**
3103
** <li>
3104
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
3105
** [error codes] or [extended error codes].  ^The legacy behavior was that
3106
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
3107
** and the application would have to make a second call to [sqlite3_reset()]
3108
** in order to find the underlying cause of the problem. With the "v2" prepare
3109
** interfaces, the underlying reason for the error is returned immediately.
3110
** </li>
3111
**
3112
** <li>
3113
** ^If the specific value bound to [parameter | host parameter] in the 
3114
** WHERE clause might influence the choice of query plan for a statement,
3115
** then the statement will be automatically recompiled, as if there had been 
3116
** a schema change, on the first  [sqlite3_step()] call following any change
3117
** to the [sqlite3_bind_text | bindings] of that [parameter]. 
3118
** ^The specific value of WHERE-clause [parameter] might influence the 
3119
** choice of query plan if the parameter is the left-hand side of a [LIKE]
3120
** or [GLOB] operator or if the parameter is compared to an indexed column
3121
** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
3122
** </li>
3123
** </ol>
3124
*/
3125
SQLITE_API int sqlite3_prepare(
3126
  sqlite3 *db,            /* Database handle */
3127
  const char *zSql,       /* SQL statement, UTF-8 encoded */
3128
  int nByte,              /* Maximum length of zSql in bytes. */
3129
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3130
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
3131
);
3132
SQLITE_API int sqlite3_prepare_v2(
3133
  sqlite3 *db,            /* Database handle */
3134
  const char *zSql,       /* SQL statement, UTF-8 encoded */
3135
  int nByte,              /* Maximum length of zSql in bytes. */
3136
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3137
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
3138
);
3139
SQLITE_API int sqlite3_prepare16(
3140
  sqlite3 *db,            /* Database handle */
3141
  const void *zSql,       /* SQL statement, UTF-16 encoded */
3142
  int nByte,              /* Maximum length of zSql in bytes. */
3143
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3144
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
3145
);
3146
SQLITE_API int sqlite3_prepare16_v2(
3147
  sqlite3 *db,            /* Database handle */
3148
  const void *zSql,       /* SQL statement, UTF-16 encoded */
3149
  int nByte,              /* Maximum length of zSql in bytes. */
3150
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3151
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
3152
);
3153
3154
/*
3155
** CAPI3REF: Retrieving Statement SQL
3156
**
3157
** ^This interface can be used to retrieve a saved copy of the original
3158
** SQL text used to create a [prepared statement] if that statement was
3159
** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
3160
*/
3161
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
3162
3163
/*
3164
** CAPI3REF: Determine If An SQL Statement Writes The Database
3165
**
3166
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
3167
** and only if the [prepared statement] X makes no direct changes to
3168
** the content of the database file.
3169
**
3170
** Note that [application-defined SQL functions] or
3171
** [virtual tables] might change the database indirectly as a side effect.  
3172
** ^(For example, if an application defines a function "eval()" that 
3173
** calls [sqlite3_exec()], then the following SQL statement would
3174
** change the database file through side-effects:
3175
**
3176
** <blockquote><pre>
3177
**    SELECT eval('DELETE FROM t1') FROM t2;
3178
** </pre></blockquote>
3179
**
3180
** But because the [SELECT] statement does not change the database file
3181
** directly, sqlite3_stmt_readonly() would still return true.)^
3182
**
3183
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
3184
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
3185
** since the statements themselves do not actually modify the database but
3186
** rather they control the timing of when other statements modify the 
3187
** database.  ^The [ATTACH] and [DETACH] statements also cause
3188
** sqlite3_stmt_readonly() to return true since, while those statements
3189
** change the configuration of a database connection, they do not make 
3190
** changes to the content of the database files on disk.
3191
*/
3192
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
3193
3194
/*
3195
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
3196
**
3197
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
3198
** [prepared statement] S has been stepped at least once using 
3199
** [sqlite3_step(S)] but has not run to completion and/or has not 
3200
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
3201
** interface returns false if S is a NULL pointer.  If S is not a 
3202
** NULL pointer and is not a pointer to a valid [prepared statement]
3203
** object, then the behavior is undefined and probably undesirable.
3204
**
3205
** This interface can be used in combination [sqlite3_next_stmt()]
3206
** to locate all prepared statements associated with a database 
3207
** connection that are in need of being reset.  This can be used,
3208
** for example, in diagnostic routines to search for prepared 
3209
** statements that are holding a transaction open.
3210
*/
3211
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
3212
3213
/*
3214
** CAPI3REF: Dynamically Typed Value Object
3215
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
3216
**
3217
** SQLite uses the sqlite3_value object to represent all values
3218
** that can be stored in a database table. SQLite uses dynamic typing
3219
** for the values it stores.  ^Values stored in sqlite3_value objects
3220
** can be integers, floating point values, strings, BLOBs, or NULL.
3221
**
3222
** An sqlite3_value object may be either "protected" or "unprotected".
3223
** Some interfaces require a protected sqlite3_value.  Other interfaces
3224
** will accept either a protected or an unprotected sqlite3_value.
3225
** Every interface that accepts sqlite3_value arguments specifies
3226
** whether or not it requires a protected sqlite3_value.
3227
**
3228
** The terms "protected" and "unprotected" refer to whether or not
3229
** a mutex is held.  An internal mutex is held for a protected
3230
** sqlite3_value object but no mutex is held for an unprotected
3231
** sqlite3_value object.  If SQLite is compiled to be single-threaded
3232
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
3233
** or if SQLite is run in one of reduced mutex modes 
3234
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
3235
** then there is no distinction between protected and unprotected
3236
** sqlite3_value objects and they can be used interchangeably.  However,
3237
** for maximum code portability it is recommended that applications
3238
** still make the distinction between protected and unprotected
3239
** sqlite3_value objects even when not strictly required.
3240
**
3241
** ^The sqlite3_value objects that are passed as parameters into the
3242
** implementation of [application-defined SQL functions] are protected.
3243
** ^The sqlite3_value object returned by
3244
** [sqlite3_column_value()] is unprotected.
3245
** Unprotected sqlite3_value objects may only be used with
3246
** [sqlite3_result_value()] and [sqlite3_bind_value()].
3247
** The [sqlite3_value_blob | sqlite3_value_type()] family of
3248
** interfaces require protected sqlite3_value objects.
3249
*/
3250
typedef struct Mem sqlite3_value;
3251
3252
/*
3253
** CAPI3REF: SQL Function Context Object
3254
**
3255
** The context in which an SQL function executes is stored in an
3256
** sqlite3_context object.  ^A pointer to an sqlite3_context object
3257
** is always first parameter to [application-defined SQL functions].
3258
** The application-defined SQL function implementation will pass this
3259
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
3260
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
3261
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
3262
** and/or [sqlite3_set_auxdata()].
3263
*/
3264
typedef struct sqlite3_context sqlite3_context;
3265
3266
/*
3267
** CAPI3REF: Binding Values To Prepared Statements
3268
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
3269
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
3270
**
3271
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
3272
** literals may be replaced by a [parameter] that matches one of following
3273
** templates:
3274
**
3275
** <ul>
3276
** <li>  ?
3277
** <li>  ?NNN
3278
** <li>  :VVV
3279
** <li>  @VVV
3280
** <li>  $VVV
3281
** </ul>
3282
**
3283
** In the templates above, NNN represents an integer literal,
3284
** and VVV represents an alphanumeric identifier.)^  ^The values of these
3285
** parameters (also called "host parameter names" or "SQL parameters")
3286
** can be set using the sqlite3_bind_*() routines defined here.
3287
**
3288
** ^The first argument to the sqlite3_bind_*() routines is always
3289
** a pointer to the [sqlite3_stmt] object returned from
3290
** [sqlite3_prepare_v2()] or its variants.
3291
**
3292
** ^The second argument is the index of the SQL parameter to be set.
3293
** ^The leftmost SQL parameter has an index of 1.  ^When the same named
3294
** SQL parameter is used more than once, second and subsequent
3295
** occurrences have the same index as the first occurrence.
3296
** ^The index for named parameters can be looked up using the
3297
** [sqlite3_bind_parameter_index()] API if desired.  ^The index
3298
** for "?NNN" parameters is the value of NNN.
3299
** ^The NNN value must be between 1 and the [sqlite3_limit()]
3300
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
3301
**
3302
** ^The third argument is the value to bind to the parameter.
3303
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3304
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
3305
** is ignored and the end result is the same as sqlite3_bind_null().
3306
**
3307
** ^(In those routines that have a fourth argument, its value is the
3308
** number of bytes in the parameter.  To be clear: the value is the
3309
** number of <u>bytes</u> in the value, not the number of characters.)^
3310
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3311
** is negative, then the length of the string is
3312
** the number of bytes up to the first zero terminator.
3313
** If the fourth parameter to sqlite3_bind_blob() is negative, then
3314
** the behavior is undefined.
3315
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
3316
** or sqlite3_bind_text16() then that parameter must be the byte offset
3317
** where the NUL terminator would occur assuming the string were NUL
3318
** terminated.  If any NUL characters occur at byte offsets less than 
3319
** the value of the fourth parameter then the resulting string value will
3320
** contain embedded NULs.  The result of expressions involving strings
3321
** with embedded NULs is undefined.
3322
**
3323
** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
3324
** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
3325
** string after SQLite has finished with it.  ^The destructor is called
3326
** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
3327
** sqlite3_bind_text(), or sqlite3_bind_text16() fails.  
3328
** ^If the fifth argument is
3329
** the special value [SQLITE_STATIC], then SQLite assumes that the
3330
** information is in static, unmanaged space and does not need to be freed.
3331
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
3332
** SQLite makes its own private copy of the data immediately, before
3333
** the sqlite3_bind_*() routine returns.
3334
**
3335
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
3336
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
3337
** (just an integer to hold its size) while it is being processed.
3338
** Zeroblobs are intended to serve as placeholders for BLOBs whose
3339
** content is later written using
3340
** [sqlite3_blob_open | incremental BLOB I/O] routines.
3341
** ^A negative value for the zeroblob results in a zero-length BLOB.
3342
**
3343
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
3344
** for the [prepared statement] or with a prepared statement for which
3345
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
3346
** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
3347
** routine is passed a [prepared statement] that has been finalized, the
3348
** result is undefined and probably harmful.
3349
**
3350
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
3351
** ^Unbound parameters are interpreted as NULL.
3352
**
3353
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
3354
** [error code] if anything goes wrong.
3355
** ^[SQLITE_RANGE] is returned if the parameter
3356
** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
3357
**
3358
** See also: [sqlite3_bind_parameter_count()],
3359
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
3360
*/
3361
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
3362
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
3363
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
3364
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
3365
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
3366
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
3367
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
3368
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
3369
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
3370
3371
/*
3372
** CAPI3REF: Number Of SQL Parameters
3373
**
3374
** ^This routine can be used to find the number of [SQL parameters]
3375
** in a [prepared statement].  SQL parameters are tokens of the
3376
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
3377
** placeholders for values that are [sqlite3_bind_blob | bound]
3378
** to the parameters at a later time.
3379
**
3380
** ^(This routine actually returns the index of the largest (rightmost)
3381
** parameter. For all forms except ?NNN, this will correspond to the
3382
** number of unique parameters.  If parameters of the ?NNN form are used,
3383
** there may be gaps in the list.)^
3384
**
3385
** See also: [sqlite3_bind_blob|sqlite3_bind()],
3386
** [sqlite3_bind_parameter_name()], and
3387
** [sqlite3_bind_parameter_index()].
3388
*/
3389
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
3390
3391
/*
3392
** CAPI3REF: Name Of A Host Parameter
3393
**
3394
** ^The sqlite3_bind_parameter_name(P,N) interface returns
3395
** the name of the N-th [SQL parameter] in the [prepared statement] P.
3396
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
3397
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
3398
** respectively.
3399
** In other words, the initial ":" or "$" or "@" or "?"
3400
** is included as part of the name.)^
3401
** ^Parameters of the form "?" without a following integer have no name
3402
** and are referred to as "nameless" or "anonymous parameters".
3403
**
3404
** ^The first host parameter has an index of 1, not 0.
3405
**
3406
** ^If the value N is out of range or if the N-th parameter is
3407
** nameless, then NULL is returned.  ^The returned string is
3408
** always in UTF-8 encoding even if the named parameter was
3409
** originally specified as UTF-16 in [sqlite3_prepare16()] or
3410
** [sqlite3_prepare16_v2()].
3411
**
3412
** See also: [sqlite3_bind_blob|sqlite3_bind()],
3413
** [sqlite3_bind_parameter_count()], and
3414
** [sqlite3_bind_parameter_index()].
3415
*/
3416
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
3417
3418
/*
3419
** CAPI3REF: Index Of A Parameter With A Given Name
3420
**
3421
** ^Return the index of an SQL parameter given its name.  ^The
3422
** index value returned is suitable for use as the second
3423
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
3424
** is returned if no matching parameter is found.  ^The parameter
3425
** name must be given in UTF-8 even if the original statement
3426
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
3427
**
3428
** See also: [sqlite3_bind_blob|sqlite3_bind()],
3429
** [sqlite3_bind_parameter_count()], and
3430
** [sqlite3_bind_parameter_index()].
3431
*/
3432
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
3433
3434
/*
3435
** CAPI3REF: Reset All Bindings On A Prepared Statement
3436
**
3437
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
3438
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
3439
** ^Use this routine to reset all host parameters to NULL.
3440
*/
3441
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
3442
3443
/*
3444
** CAPI3REF: Number Of Columns In A Result Set
3445
**
3446
** ^Return the number of columns in the result set returned by the
3447
** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
3448
** statement that does not return data (for example an [UPDATE]).
3449
**
3450
** See also: [sqlite3_data_count()]
3451
*/
3452
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
3453
3454
/*
3455
** CAPI3REF: Column Names In A Result Set
3456
**
3457
** ^These routines return the name assigned to a particular column
3458
** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
3459
** interface returns a pointer to a zero-terminated UTF-8 string
3460
** and sqlite3_column_name16() returns a pointer to a zero-terminated
3461
** UTF-16 string.  ^The first parameter is the [prepared statement]
3462
** that implements the [SELECT] statement. ^The second parameter is the
3463
** column number.  ^The leftmost column is number 0.
3464
**
3465
** ^The returned string pointer is valid until either the [prepared statement]
3466
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
3467
** reprepared by the first call to [sqlite3_step()] for a particular run
3468
** or until the next call to
3469
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
3470
**
3471
** ^If sqlite3_malloc() fails during the processing of either routine
3472
** (for example during a conversion from UTF-8 to UTF-16) then a
3473
** NULL pointer is returned.
3474
**
3475
** ^The name of a result column is the value of the "AS" clause for
3476
** that column, if there is an AS clause.  If there is no AS clause
3477
** then the name of the column is unspecified and may change from
3478
** one release of SQLite to the next.
3479
*/
3480
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
3481
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
3482
3483
/*
3484
** CAPI3REF: Source Of Data In A Query Result
3485
**
3486
** ^These routines provide a means to determine the database, table, and
3487
** table column that is the origin of a particular result column in
3488
** [SELECT] statement.
3489
** ^The name of the database or table or column can be returned as
3490
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
3491
** the database name, the _table_ routines return the table name, and
3492
** the origin_ routines return the column name.
3493
** ^The returned string is valid until the [prepared statement] is destroyed
3494
** using [sqlite3_finalize()] or until the statement is automatically
3495
** reprepared by the first call to [sqlite3_step()] for a particular run
3496
** or until the same information is requested
3497
** again in a different encoding.
3498
**
3499
** ^The names returned are the original un-aliased names of the
3500
** database, table, and column.
3501
**
3502
** ^The first argument to these interfaces is a [prepared statement].
3503
** ^These functions return information about the Nth result column returned by
3504
** the statement, where N is the second function argument.
3505
** ^The left-most column is column 0 for these routines.
3506
**
3507
** ^If the Nth column returned by the statement is an expression or
3508
** subquery and is not a column value, then all of these functions return
3509
** NULL.  ^These routine might also return NULL if a memory allocation error
3510
** occurs.  ^Otherwise, they return the name of the attached database, table,
3511
** or column that query result column was extracted from.
3512
**
3513
** ^As with all other SQLite APIs, those whose names end with "16" return
3514
** UTF-16 encoded strings and the other functions return UTF-8.
3515
**
3516
** ^These APIs are only available if the library was compiled with the
3517
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
3518
**
3519
** If two or more threads call one or more of these routines against the same
3520
** prepared statement and column at the same time then the results are
3521
** undefined.
3522
**
3523
** If two or more threads call one or more
3524
** [sqlite3_column_database_name | column metadata interfaces]
3525
** for the same [prepared statement] and result column
3526
** at the same time then the results are undefined.
3527
*/
3528
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
3529
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
3530
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
3531
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
3532
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
3533
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
3534
3535
/*
3536
** CAPI3REF: Declared Datatype Of A Query Result
3537
**
3538
** ^(The first parameter is a [prepared statement].
3539
** If this statement is a [SELECT] statement and the Nth column of the
3540
** returned result set of that [SELECT] is a table column (not an
3541
** expression or subquery) then the declared type of the table
3542
** column is returned.)^  ^If the Nth column of the result set is an
3543
** expression or subquery, then a NULL pointer is returned.
3544
** ^The returned string is always UTF-8 encoded.
3545
**
3546
** ^(For example, given the database schema:
3547
**
3548
** CREATE TABLE t1(c1 VARIANT);
3549
**
3550
** and the following statement to be compiled:
3551
**
3552
** SELECT c1 + 1, c1 FROM t1;
3553
**
3554
** this routine would return the string "VARIANT" for the second result
3555
** column (i==1), and a NULL pointer for the first result column (i==0).)^
3556
**
3557
** ^SQLite uses dynamic run-time typing.  ^So just because a column
3558
** is declared to contain a particular type does not mean that the
3559
** data stored in that column is of the declared type.  SQLite is
3560
** strongly typed, but the typing is dynamic not static.  ^Type
3561
** is associated with individual values, not with the containers
3562
** used to hold those values.
3563
*/
3564
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
3565
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
3566
3567
/*
3568
** CAPI3REF: Evaluate An SQL Statement
3569
**
3570
** After a [prepared statement] has been prepared using either
3571
** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
3572
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
3573
** must be called one or more times to evaluate the statement.
3574
**
3575
** The details of the behavior of the sqlite3_step() interface depend
3576
** on whether the statement was prepared using the newer "v2" interface
3577
** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
3578
** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
3579
** new "v2" interface is recommended for new applications but the legacy
3580
** interface will continue to be supported.
3581
**
3582
** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
3583
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
3584
** ^With the "v2" interface, any of the other [result codes] or
3585
** [extended result codes] might be returned as well.
3586
**
3587
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
3588
** database locks it needs to do its job.  ^If the statement is a [COMMIT]
3589
** or occurs outside of an explicit transaction, then you can retry the
3590
** statement.  If the statement is not a [COMMIT] and occurs within an
3591
** explicit transaction then you should rollback the transaction before
3592
** continuing.
3593
**
3594
** ^[SQLITE_DONE] means that the statement has finished executing
3595
** successfully.  sqlite3_step() should not be called again on this virtual
3596
** machine without first calling [sqlite3_reset()] to reset the virtual
3597
** machine back to its initial state.
3598
**
3599
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
3600
** is returned each time a new row of data is ready for processing by the
3601
** caller. The values may be accessed using the [column access functions].
3602
** sqlite3_step() is called again to retrieve the next row of data.
3603
**
3604
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
3605
** violation) has occurred.  sqlite3_step() should not be called again on
3606
** the VM. More information may be found by calling [sqlite3_errmsg()].
3607
** ^With the legacy interface, a more specific error code (for example,
3608
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
3609
** can be obtained by calling [sqlite3_reset()] on the
3610
** [prepared statement].  ^In the "v2" interface,
3611
** the more specific error code is returned directly by sqlite3_step().
3612
**
3613
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
3614
** Perhaps it was called on a [prepared statement] that has
3615
** already been [sqlite3_finalize | finalized] or on one that had
3616
** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
3617
** be the case that the same database connection is being used by two or
3618
** more threads at the same moment in time.
3619
**
3620
** For all versions of SQLite up to and including 3.6.23.1, a call to
3621
** [sqlite3_reset()] was required after sqlite3_step() returned anything
3622
** other than [SQLITE_ROW] before any subsequent invocation of
3623
** sqlite3_step().  Failure to reset the prepared statement using 
3624
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
3625
** sqlite3_step().  But after version 3.6.23.1, sqlite3_step() began
3626
** calling [sqlite3_reset()] automatically in this circumstance rather
3627
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
3628
** break because any application that ever receives an SQLITE_MISUSE error
3629
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
3630
** can be used to restore the legacy behavior.
3631
**
3632
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
3633
** API always returns a generic error code, [SQLITE_ERROR], following any
3634
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
3635
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
3636
** specific [error codes] that better describes the error.
3637
** We admit that this is a goofy design.  The problem has been fixed
3638
** with the "v2" interface.  If you prepare all of your SQL statements
3639
** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
3640
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
3641
** then the more specific [error codes] are returned directly
3642
** by sqlite3_step().  The use of the "v2" interface is recommended.
3643
*/
3644
SQLITE_API int sqlite3_step(sqlite3_stmt*);
3645
3646
/*
3647
** CAPI3REF: Number of columns in a result set
3648
**
3649
** ^The sqlite3_data_count(P) interface returns the number of columns in the
3650
** current row of the result set of [prepared statement] P.
3651
** ^If prepared statement P does not have results ready to return
3652
** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
3653
** interfaces) then sqlite3_data_count(P) returns 0.
3654
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
3655
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
3656
** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
3657
** will return non-zero if previous call to [sqlite3_step](P) returned
3658
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
3659
** where it always returns zero since each step of that multi-step
3660
** pragma returns 0 columns of data.
3661
**
3662
** See also: [sqlite3_column_count()]
3663
*/
3664
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
3665
3666
/*
3667
** CAPI3REF: Fundamental Datatypes
3668
** KEYWORDS: SQLITE_TEXT
3669
**
3670
** ^(Every value in SQLite has one of five fundamental datatypes:
3671
**
3672
** <ul>
3673
** <li> 64-bit signed integer
3674
** <li> 64-bit IEEE floating point number
3675
** <li> string
3676
** <li> BLOB
3677
** <li> NULL
3678
** </ul>)^
3679
**
3680
** These constants are codes for each of those types.
3681
**
3682
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
3683
** for a completely different meaning.  Software that links against both
3684
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
3685
** SQLITE_TEXT.
3686
*/
3687
#define SQLITE_INTEGER  1
3688
#define SQLITE_FLOAT    2
3689
#define SQLITE_BLOB     4
3690
#define SQLITE_NULL     5
3691
#ifdef SQLITE_TEXT
3692
# undef SQLITE_TEXT
3693
#else
3694
# define SQLITE_TEXT     3
3695
#endif
3696
#define SQLITE3_TEXT     3
3697
3698
/*
3699
** CAPI3REF: Result Values From A Query
3700
** KEYWORDS: {column access functions}
3701
**
3702
** These routines form the "result set" interface.
3703
**
3704
** ^These routines return information about a single column of the current
3705
** result row of a query.  ^In every case the first argument is a pointer
3706
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
3707
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
3708
** and the second argument is the index of the column for which information
3709
** should be returned. ^The leftmost column of the result set has the index 0.
3710
** ^The number of columns in the result can be determined using
3711
** [sqlite3_column_count()].
3712
**
3713
** If the SQL statement does not currently point to a valid row, or if the
3714
** column index is out of range, the result is undefined.
3715
** These routines may only be called when the most recent call to
3716
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
3717
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
3718
** If any of these routines are called after [sqlite3_reset()] or
3719
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
3720
** something other than [SQLITE_ROW], the results are undefined.
3721
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
3722
** are called from a different thread while any of these routines
3723
** are pending, then the results are undefined.
3724
**
3725
** ^The sqlite3_column_type() routine returns the
3726
** [SQLITE_INTEGER | datatype code] for the initial data type
3727
** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
3728
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
3729
** returned by sqlite3_column_type() is only meaningful if no type
3730
** conversions have occurred as described below.  After a type conversion,
3731
** the value returned by sqlite3_column_type() is undefined.  Future
3732
** versions of SQLite may change the behavior of sqlite3_column_type()
3733
** following a type conversion.
3734
**
3735
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
3736
** routine returns the number of bytes in that BLOB or string.
3737
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
3738
** the string to UTF-8 and then returns the number of bytes.
3739
** ^If the result is a numeric value then sqlite3_column_bytes() uses
3740
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
3741
** the number of bytes in that string.
3742
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
3743
**
3744
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
3745
** routine returns the number of bytes in that BLOB or string.
3746
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
3747
** the string to UTF-16 and then returns the number of bytes.
3748
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
3749
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
3750
** the number of bytes in that string.
3751
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
3752
**
3753
** ^The values returned by [sqlite3_column_bytes()] and 
3754
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
3755
** of the string.  ^For clarity: the values returned by
3756
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
3757
** bytes in the string, not the number of characters.
3758
**
3759
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
3760
** even empty strings, are always zero-terminated.  ^The return
3761
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
3762
**
3763
** ^The object returned by [sqlite3_column_value()] is an
3764
** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
3765
** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
3766
** If the [unprotected sqlite3_value] object returned by
3767
** [sqlite3_column_value()] is used in any other way, including calls
3768
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
3769
** or [sqlite3_value_bytes()], then the behavior is undefined.
3770
**
3771
** These routines attempt to convert the value where appropriate.  ^For
3772
** example, if the internal representation is FLOAT and a text result
3773
** is requested, [sqlite3_snprintf()] is used internally to perform the
3774
** conversion automatically.  ^(The following table details the conversions
3775
** that are applied:
3776
**
3777
** <blockquote>
3778
** <table border="1">
3779
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
3780
**
3781
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
3782
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
3783
** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
3784
** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
3785
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
3786
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
3787
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
3788
** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
3789
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
3790
** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
3791
** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
3792
** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
3793
** <tr><td>  TEXT    <td>   BLOB    <td> No change
3794
** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
3795
** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
3796
** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
3797
** </table>
3798
** </blockquote>)^
3799
**
3800
** The table above makes reference to standard C library functions atoi()
3801
** and atof().  SQLite does not really use these functions.  It has its
3802
** own equivalent internal routines.  The atoi() and atof() names are
3803
** used in the table for brevity and because they are familiar to most
3804
** C programmers.
3805
**
3806
** Note that when type conversions occur, pointers returned by prior
3807
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
3808
** sqlite3_column_text16() may be invalidated.
3809
** Type conversions and pointer invalidations might occur
3810
** in the following cases:
3811
**
3812
** <ul>
3813
** <li> The initial content is a BLOB and sqlite3_column_text() or
3814
**      sqlite3_column_text16() is called.  A zero-terminator might
3815
**      need to be added to the string.</li>
3816
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
3817
**      sqlite3_column_text16() is called.  The content must be converted
3818
**      to UTF-16.</li>
3819
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
3820
**      sqlite3_column_text() is called.  The content must be converted
3821
**      to UTF-8.</li>
3822
** </ul>
3823
**
3824
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
3825
** not invalidate a prior pointer, though of course the content of the buffer
3826
** that the prior pointer references will have been modified.  Other kinds
3827
** of conversion are done in place when it is possible, but sometimes they
3828
** are not possible and in those cases prior pointers are invalidated.
3829
**
3830
** The safest and easiest to remember policy is to invoke these routines
3831
** in one of the following ways:
3832
**
3833
** <ul>
3834
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
3835
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
3836
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
3837
** </ul>
3838
**
3839
** In other words, you should call sqlite3_column_text(),
3840
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
3841
** into the desired format, then invoke sqlite3_column_bytes() or
3842
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
3843
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
3844
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
3845
** with calls to sqlite3_column_bytes().
3846
**
3847
** ^The pointers returned are valid until a type conversion occurs as
3848
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
3849
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
3850
** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
3851
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
3852
** [sqlite3_free()].
3853
**
3854
** ^(If a memory allocation error occurs during the evaluation of any
3855
** of these routines, a default value is returned.  The default value
3856
** is either the integer 0, the floating point number 0.0, or a NULL
3857
** pointer.  Subsequent calls to [sqlite3_errcode()] will return
3858
** [SQLITE_NOMEM].)^
3859
*/
3860
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
3861
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
3862
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
3863
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
3864
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
3865
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
3866
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
3867
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
3868
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
3869
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
3870
3871
/*
3872
** CAPI3REF: Destroy A Prepared Statement Object
3873
**
3874
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
3875
** ^If the most recent evaluation of the statement encountered no errors
3876
** or if the statement is never been evaluated, then sqlite3_finalize() returns
3877
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
3878
** sqlite3_finalize(S) returns the appropriate [error code] or
3879
** [extended error code].
3880
**
3881
** ^The sqlite3_finalize(S) routine can be called at any point during
3882
** the life cycle of [prepared statement] S:
3883
** before statement S is ever evaluated, after
3884
** one or more calls to [sqlite3_reset()], or after any call
3885
** to [sqlite3_step()] regardless of whether or not the statement has
3886
** completed execution.
3887
**
3888
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
3889
**
3890
** The application must finalize every [prepared statement] in order to avoid
3891
** resource leaks.  It is a grievous error for the application to try to use
3892
** a prepared statement after it has been finalized.  Any use of a prepared
3893
** statement after it has been finalized can result in undefined and
3894
** undesirable behavior such as segfaults and heap corruption.
3895
*/
3896
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
3897
3898
/*
3899
** CAPI3REF: Reset A Prepared Statement Object
3900
**
3901
** The sqlite3_reset() function is called to reset a [prepared statement]
3902
** object back to its initial state, ready to be re-executed.
3903
** ^Any SQL statement variables that had values bound to them using
3904
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
3905
** Use [sqlite3_clear_bindings()] to reset the bindings.
3906
**
3907
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
3908
** back to the beginning of its program.
3909
**
3910
** ^If the most recent call to [sqlite3_step(S)] for the
3911
** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
3912
** or if [sqlite3_step(S)] has never before been called on S,
3913
** then [sqlite3_reset(S)] returns [SQLITE_OK].
3914
**
3915
** ^If the most recent call to [sqlite3_step(S)] for the
3916
** [prepared statement] S indicated an error, then
3917
** [sqlite3_reset(S)] returns an appropriate [error code].
3918
**
3919
** ^The [sqlite3_reset(S)] interface does not change the values
3920
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
3921
*/
3922
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
3923
3924
/*
3925
** CAPI3REF: Create Or Redefine SQL Functions
3926
** KEYWORDS: {function creation routines}
3927
** KEYWORDS: {application-defined SQL function}
3928
** KEYWORDS: {application-defined SQL functions}
3929
**
3930
** ^These functions (collectively known as "function creation routines")
3931
** are used to add SQL functions or aggregates or to redefine the behavior
3932
** of existing SQL functions or aggregates.  The only differences between
3933
** these routines are the text encoding expected for
3934
** the second parameter (the name of the function being created)
3935
** and the presence or absence of a destructor callback for
3936
** the application data pointer.
3937
**
3938
** ^The first parameter is the [database connection] to which the SQL
3939
** function is to be added.  ^If an application uses more than one database
3940
** connection then application-defined SQL functions must be added
3941
** to each database connection separately.
3942
**
3943
** ^The second parameter is the name of the SQL function to be created or
3944
** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
3945
** representation, exclusive of the zero-terminator.  ^Note that the name
3946
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
3947
** ^Any attempt to create a function with a longer name
3948
** will result in [SQLITE_MISUSE] being returned.
3949
**
3950
** ^The third parameter (nArg)
3951
** is the number of arguments that the SQL function or
3952
** aggregate takes. ^If this parameter is -1, then the SQL function or
3953
** aggregate may take any number of arguments between 0 and the limit
3954
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
3955
** parameter is less than -1 or greater than 127 then the behavior is
3956
** undefined.
3957
**
3958
** ^The fourth parameter, eTextRep, specifies what
3959
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
3960
** its parameters.  Every SQL function implementation must be able to work
3961
** with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
3962
** more efficient with one encoding than another.  ^An application may
3963
** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
3964
** times with the same function but with different values of eTextRep.
3965
** ^When multiple implementations of the same function are available, SQLite
3966
** will pick the one that involves the least amount of data conversion.
3967
** If there is only a single implementation which does not care what text
3968
** encoding is used, then the fourth argument should be [SQLITE_ANY].
3969
**
3970
** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
3971
** function can gain access to this pointer using [sqlite3_user_data()].)^
3972
**
3973
** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
3974
** pointers to C-language functions that implement the SQL function or
3975
** aggregate. ^A scalar SQL function requires an implementation of the xFunc
3976
** callback only; NULL pointers must be passed as the xStep and xFinal
3977
** parameters. ^An aggregate SQL function requires an implementation of xStep
3978
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
3979
** SQL function or aggregate, pass NULL pointers for all three function
3980
** callbacks.
3981
**
3982
** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
3983
** then it is destructor for the application data pointer. 
3984
** The destructor is invoked when the function is deleted, either by being
3985
** overloaded or when the database connection closes.)^
3986
** ^The destructor is also invoked if the call to
3987
** sqlite3_create_function_v2() fails.
3988
** ^When the destructor callback of the tenth parameter is invoked, it
3989
** is passed a single argument which is a copy of the application data 
3990
** pointer which was the fifth parameter to sqlite3_create_function_v2().
3991
**
3992
** ^It is permitted to register multiple implementations of the same
3993
** functions with the same name but with either differing numbers of
3994
** arguments or differing preferred text encodings.  ^SQLite will use
3995
** the implementation that most closely matches the way in which the
3996
** SQL function is used.  ^A function implementation with a non-negative
3997
** nArg parameter is a better match than a function implementation with
3998
** a negative nArg.  ^A function where the preferred text encoding
3999
** matches the database encoding is a better
4000
** match than a function where the encoding is different.  
4001
** ^A function where the encoding difference is between UTF16le and UTF16be
4002
** is a closer match than a function where the encoding difference is
4003
** between UTF8 and UTF16.
4004
**
4005
** ^Built-in functions may be overloaded by new application-defined functions.
4006
**
4007
** ^An application-defined function is permitted to call other
4008
** SQLite interfaces.  However, such calls must not
4009
** close the database connection nor finalize or reset the prepared
4010
** statement in which the function is running.
4011
*/
4012
SQLITE_API int sqlite3_create_function(
4013
  sqlite3 *db,
4014
  const char *zFunctionName,
4015
  int nArg,
4016
  int eTextRep,
4017
  void *pApp,
4018
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4019
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4020
  void (*xFinal)(sqlite3_context*)
4021
);
4022
SQLITE_API int sqlite3_create_function16(
4023
  sqlite3 *db,
4024
  const void *zFunctionName,
4025
  int nArg,
4026
  int eTextRep,
4027
  void *pApp,
4028
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4029
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4030
  void (*xFinal)(sqlite3_context*)
4031
);
4032
SQLITE_API int sqlite3_create_function_v2(
4033
  sqlite3 *db,
4034
  const char *zFunctionName,
4035
  int nArg,
4036
  int eTextRep,
4037
  void *pApp,
4038
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4039
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4040
  void (*xFinal)(sqlite3_context*),
4041
  void(*xDestroy)(void*)
4042
);
4043
4044
/*
4045
** CAPI3REF: Text Encodings
4046
**
4047
** These constant define integer codes that represent the various
4048
** text encodings supported by SQLite.
4049
*/
4050
#define SQLITE_UTF8           1
4051
#define SQLITE_UTF16LE        2
4052
#define SQLITE_UTF16BE        3
4053
#define SQLITE_UTF16          4    /* Use native byte order */
4054
#define SQLITE_ANY            5    /* sqlite3_create_function only */
4055
#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
4056
4057
/*
4058
** CAPI3REF: Deprecated Functions
4059
** DEPRECATED
4060
**
4061
** These functions are [deprecated].  In order to maintain
4062
** backwards compatibility with older code, these functions continue 
4063
** to be supported.  However, new applications should avoid
4064
** the use of these functions.  To help encourage people to avoid
4065
** using these functions, we are not going to tell you what they do.
4066
*/
4067
#ifndef SQLITE_OMIT_DEPRECATED
4068
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
4069
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
4070
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
4071
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
4072
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
4073
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
4074
                      void*,sqlite3_int64);
4075
#endif
4076
4077
/*
4078
** CAPI3REF: Obtaining SQL Function Parameter Values
4079
**
4080
** The C-language implementation of SQL functions and aggregates uses
4081
** this set of interface routines to access the parameter values on
4082
** the function or aggregate.
4083
**
4084
** The xFunc (for scalar functions) or xStep (for aggregates) parameters
4085
** to [sqlite3_create_function()] and [sqlite3_create_function16()]
4086
** define callbacks that implement the SQL functions and aggregates.
4087
** The 3rd parameter to these callbacks is an array of pointers to
4088
** [protected sqlite3_value] objects.  There is one [sqlite3_value] object for
4089
** each parameter to the SQL function.  These routines are used to
4090
** extract values from the [sqlite3_value] objects.
4091
**
4092
** These routines work only with [protected sqlite3_value] objects.
4093
** Any attempt to use these routines on an [unprotected sqlite3_value]
4094
** object results in undefined behavior.
4095
**
4096
** ^These routines work just like the corresponding [column access functions]
4097
** except that  these routines take a single [protected sqlite3_value] object
4098
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
4099
**
4100
** ^The sqlite3_value_text16() interface extracts a UTF-16 string
4101
** in the native byte-order of the host machine.  ^The
4102
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
4103
** extract UTF-16 strings as big-endian and little-endian respectively.
4104
**
4105
** ^(The sqlite3_value_numeric_type() interface attempts to apply
4106
** numeric affinity to the value.  This means that an attempt is
4107
** made to convert the value to an integer or floating point.  If
4108
** such a conversion is possible without loss of information (in other
4109
** words, if the value is a string that looks like a number)
4110
** then the conversion is performed.  Otherwise no conversion occurs.
4111
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
4112
**
4113
** Please pay particular attention to the fact that the pointer returned
4114
** from [sqlite3_value_blob()], [sqlite3_value_text()], or
4115
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
4116
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
4117
** or [sqlite3_value_text16()].
4118
**
4119
** These routines must be called from the same thread as
4120
** the SQL function that supplied the [sqlite3_value*] parameters.
4121
*/
4122
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
4123
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
4124
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
4125
SQLITE_API double sqlite3_value_double(sqlite3_value*);
4126
SQLITE_API int sqlite3_value_int(sqlite3_value*);
4127
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
4128
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
4129
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
4130
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
4131
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
4132
SQLITE_API int sqlite3_value_type(sqlite3_value*);
4133
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
4134
4135
/*
4136
** CAPI3REF: Obtain Aggregate Function Context
4137
**
4138
** Implementations of aggregate SQL functions use this
4139
** routine to allocate memory for storing their state.
4140
**
4141
** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
4142
** for a particular aggregate function, SQLite
4143
** allocates N of memory, zeroes out that memory, and returns a pointer
4144
** to the new memory. ^On second and subsequent calls to
4145
** sqlite3_aggregate_context() for the same aggregate function instance,
4146
** the same buffer is returned.  Sqlite3_aggregate_context() is normally
4147
** called once for each invocation of the xStep callback and then one
4148
** last time when the xFinal callback is invoked.  ^(When no rows match
4149
** an aggregate query, the xStep() callback of the aggregate function
4150
** implementation is never called and xFinal() is called exactly once.
4151
** In those cases, sqlite3_aggregate_context() might be called for the
4152
** first time from within xFinal().)^
4153
**
4154
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 
4155
** when first called if N is less than or equal to zero or if a memory
4156
** allocate error occurs.
4157
**
4158
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
4159
** determined by the N parameter on first successful call.  Changing the
4160
** value of N in subsequent call to sqlite3_aggregate_context() within
4161
** the same aggregate function instance will not resize the memory
4162
** allocation.)^  Within the xFinal callback, it is customary to set
4163
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 
4164
** pointless memory allocations occur.
4165
**
4166
** ^SQLite automatically frees the memory allocated by 
4167
** sqlite3_aggregate_context() when the aggregate query concludes.
4168
**
4169
** The first parameter must be a copy of the
4170
** [sqlite3_context | SQL function context] that is the first parameter
4171
** to the xStep or xFinal callback routine that implements the aggregate
4172
** function.
4173
**
4174
** This routine must be called from the same thread in which
4175
** the aggregate SQL function is running.
4176
*/
4177
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
4178
4179
/*
4180
** CAPI3REF: User Data For Functions
4181
**
4182
** ^The sqlite3_user_data() interface returns a copy of
4183
** the pointer that was the pUserData parameter (the 5th parameter)
4184
** of the [sqlite3_create_function()]
4185
** and [sqlite3_create_function16()] routines that originally
4186
** registered the application defined function.
4187
**
4188
** This routine must be called from the same thread in which
4189
** the application-defined function is running.
4190
*/
4191
SQLITE_API void *sqlite3_user_data(sqlite3_context*);
4192
4193
/*
4194
** CAPI3REF: Database Connection For Functions
4195
**
4196
** ^The sqlite3_context_db_handle() interface returns a copy of
4197
** the pointer to the [database connection] (the 1st parameter)
4198
** of the [sqlite3_create_function()]
4199
** and [sqlite3_create_function16()] routines that originally
4200
** registered the application defined function.
4201
*/
4202
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
4203
4204
/*
4205
** CAPI3REF: Function Auxiliary Data
4206
**
4207
** These functions may be used by (non-aggregate) SQL functions to
4208
** associate metadata with argument values. If the same value is passed to
4209
** multiple invocations of the same SQL function during query execution, under
4210
** some circumstances the associated metadata may be preserved.  An example
4211
** of where this might be useful is in a regular-expression matching
4212
** function. The compiled version of the regular expression can be stored as
4213
** metadata associated with the pattern string.  
4214
** Then as long as the pattern string remains the same,
4215
** the compiled regular expression can be reused on multiple
4216
** invocations of the same function.
4217
**
4218
** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
4219
** associated by the sqlite3_set_auxdata() function with the Nth argument
4220
** value to the application-defined function. ^If there is no metadata
4221
** associated with the function argument, this sqlite3_get_auxdata() interface
4222
** returns a NULL pointer.
4223
**
4224
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
4225
** argument of the application-defined function.  ^Subsequent
4226
** calls to sqlite3_get_auxdata(C,N) return P from the most recent
4227
** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
4228
** NULL if the metadata has been discarded.
4229
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
4230
** SQLite will invoke the destructor function X with parameter P exactly
4231
** once, when the metadata is discarded.
4232
** SQLite is free to discard the metadata at any time, including: <ul>
4233
** <li> when the corresponding function parameter changes, or
4234
** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
4235
**      SQL statement, or
4236
** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
4237
** <li> during the original sqlite3_set_auxdata() call when a memory 
4238
**      allocation error occurs. </ul>)^
4239
**
4240
** Note the last bullet in particular.  The destructor X in 
4241
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
4242
** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
4243
** should be called near the end of the function implementation and the
4244
** function implementation should not make any use of P after
4245
** sqlite3_set_auxdata() has been called.
4246
**
4247
** ^(In practice, metadata is preserved between function calls for
4248
** function parameters that are compile-time constants, including literal
4249
** values and [parameters] and expressions composed from the same.)^
4250
**
4251
** These routines must be called from the same thread in which
4252
** the SQL function is running.
4253
*/
4254
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
4255
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
4256
4257
4258
/*
4259
** CAPI3REF: Constants Defining Special Destructor Behavior
4260
**
4261
** These are special values for the destructor that is passed in as the
4262
** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
4263
** argument is SQLITE_STATIC, it means that the content pointer is constant
4264
** and will never change.  It does not need to be destroyed.  ^The
4265
** SQLITE_TRANSIENT value means that the content will likely change in
4266
** the near future and that SQLite should make its own private copy of
4267
** the content before returning.
4268
**
4269
** The typedef is necessary to work around problems in certain
4270
** C++ compilers.
4271
*/
4272
typedef void (*sqlite3_destructor_type)(void*);
4273
0
#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
4274
#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
4275
4276
/*
4277
** CAPI3REF: Setting The Result Of An SQL Function
4278
**
4279
** These routines are used by the xFunc or xFinal callbacks that
4280
** implement SQL functions and aggregates.  See
4281
** [sqlite3_create_function()] and [sqlite3_create_function16()]
4282
** for additional information.
4283
**
4284
** These functions work very much like the [parameter binding] family of
4285
** functions used to bind values to host parameters in prepared statements.
4286
** Refer to the [SQL parameter] documentation for additional information.
4287
**
4288
** ^The sqlite3_result_blob() interface sets the result from
4289
** an application-defined function to be the BLOB whose content is pointed
4290
** to by the second parameter and which is N bytes long where N is the
4291
** third parameter.
4292
**
4293
** ^The sqlite3_result_zeroblob() interfaces set the result of
4294
** the application-defined function to be a BLOB containing all zero
4295
** bytes and N bytes in size, where N is the value of the 2nd parameter.
4296
**
4297
** ^The sqlite3_result_double() interface sets the result from
4298
** an application-defined function to be a floating point value specified
4299
** by its 2nd argument.
4300
**
4301
** ^The sqlite3_result_error() and sqlite3_result_error16() functions
4302
** cause the implemented SQL function to throw an exception.
4303
** ^SQLite uses the string pointed to by the
4304
** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
4305
** as the text of an error message.  ^SQLite interprets the error
4306
** message string from sqlite3_result_error() as UTF-8. ^SQLite
4307
** interprets the string from sqlite3_result_error16() as UTF-16 in native
4308
** byte order.  ^If the third parameter to sqlite3_result_error()
4309
** or sqlite3_result_error16() is negative then SQLite takes as the error
4310
** message all text up through the first zero character.
4311
** ^If the third parameter to sqlite3_result_error() or
4312
** sqlite3_result_error16() is non-negative then SQLite takes that many
4313
** bytes (not characters) from the 2nd parameter as the error message.
4314
** ^The sqlite3_result_error() and sqlite3_result_error16()
4315
** routines make a private copy of the error message text before
4316
** they return.  Hence, the calling function can deallocate or
4317
** modify the text after they return without harm.
4318
** ^The sqlite3_result_error_code() function changes the error code
4319
** returned by SQLite as a result of an error in a function.  ^By default,
4320
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
4321
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
4322
**
4323
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
4324
** error indicating that a string or BLOB is too long to represent.
4325
**
4326
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
4327
** error indicating that a memory allocation failed.
4328
**
4329
** ^The sqlite3_result_int() interface sets the return value
4330
** of the application-defined function to be the 32-bit signed integer
4331
** value given in the 2nd argument.
4332
** ^The sqlite3_result_int64() interface sets the return value
4333
** of the application-defined function to be the 64-bit signed integer
4334
** value given in the 2nd argument.
4335
**
4336
** ^The sqlite3_result_null() interface sets the return value
4337
** of the application-defined function to be NULL.
4338
**
4339
** ^The sqlite3_result_text(), sqlite3_result_text16(),
4340
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
4341
** set the return value of the application-defined function to be
4342
** a text string which is represented as UTF-8, UTF-16 native byte order,
4343
** UTF-16 little endian, or UTF-16 big endian, respectively.
4344
** ^SQLite takes the text result from the application from
4345
** the 2nd parameter of the sqlite3_result_text* interfaces.
4346
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
4347
** is negative, then SQLite takes result text from the 2nd parameter
4348
** through the first zero character.
4349
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
4350
** is non-negative, then as many bytes (not characters) of the text
4351
** pointed to by the 2nd parameter are taken as the application-defined
4352
** function result.  If the 3rd parameter is non-negative, then it
4353
** must be the byte offset into the string where the NUL terminator would
4354
** appear if the string where NUL terminated.  If any NUL characters occur
4355
** in the string at a byte offset that is less than the value of the 3rd
4356
** parameter, then the resulting string will contain embedded NULs and the
4357
** result of expressions operating on strings with embedded NULs is undefined.
4358
** ^If the 4th parameter to the sqlite3_result_text* interfaces
4359
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
4360
** function as the destructor on the text or BLOB result when it has
4361
** finished using that result.
4362
** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
4363
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
4364
** assumes that the text or BLOB result is in constant space and does not
4365
** copy the content of the parameter nor call a destructor on the content
4366
** when it has finished using that result.
4367
** ^If the 4th parameter to the sqlite3_result_text* interfaces
4368
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
4369
** then SQLite makes a copy of the result into space obtained from
4370
** from [sqlite3_malloc()] before it returns.
4371
**
4372
** ^The sqlite3_result_value() interface sets the result of
4373
** the application-defined function to be a copy the
4374
** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
4375
** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
4376
** so that the [sqlite3_value] specified in the parameter may change or
4377
** be deallocated after sqlite3_result_value() returns without harm.
4378
** ^A [protected sqlite3_value] object may always be used where an
4379
** [unprotected sqlite3_value] object is required, so either
4380
** kind of [sqlite3_value] object can be used with this interface.
4381
**
4382
** If these routines are called from within the different thread
4383
** than the one containing the application-defined function that received
4384
** the [sqlite3_context] pointer, the results are undefined.
4385
*/
4386
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
4387
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
4388
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
4389
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
4390
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
4391
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
4392
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
4393
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
4394
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
4395
SQLITE_API void sqlite3_result_null(sqlite3_context*);
4396
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
4397
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
4398
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
4399
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
4400
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
4401
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
4402
4403
/*
4404
** CAPI3REF: Define New Collating Sequences
4405
**
4406
** ^These functions add, remove, or modify a [collation] associated
4407
** with the [database connection] specified as the first argument.
4408
**
4409
** ^The name of the collation is a UTF-8 string
4410
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
4411
** and a UTF-16 string in native byte order for sqlite3_create_collation16().
4412
** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
4413
** considered to be the same name.
4414
**
4415
** ^(The third argument (eTextRep) must be one of the constants:
4416
** <ul>
4417
** <li> [SQLITE_UTF8],
4418
** <li> [SQLITE_UTF16LE],
4419
** <li> [SQLITE_UTF16BE],
4420
** <li> [SQLITE_UTF16], or
4421
** <li> [SQLITE_UTF16_ALIGNED].
4422
** </ul>)^
4423
** ^The eTextRep argument determines the encoding of strings passed
4424
** to the collating function callback, xCallback.
4425
** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
4426
** force strings to be UTF16 with native byte order.
4427
** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
4428
** on an even byte address.
4429
**
4430
** ^The fourth argument, pArg, is an application data pointer that is passed
4431
** through as the first argument to the collating function callback.
4432
**
4433
** ^The fifth argument, xCallback, is a pointer to the collating function.
4434
** ^Multiple collating functions can be registered using the same name but
4435
** with different eTextRep parameters and SQLite will use whichever
4436
** function requires the least amount of data transformation.
4437
** ^If the xCallback argument is NULL then the collating function is
4438
** deleted.  ^When all collating functions having the same name are deleted,
4439
** that collation is no longer usable.
4440
**
4441
** ^The collating function callback is invoked with a copy of the pArg 
4442
** application data pointer and with two strings in the encoding specified
4443
** by the eTextRep argument.  The collating function must return an
4444
** integer that is negative, zero, or positive
4445
** if the first string is less than, equal to, or greater than the second,
4446
** respectively.  A collating function must always return the same answer
4447
** given the same inputs.  If two or more collating functions are registered
4448
** to the same collation name (using different eTextRep values) then all
4449
** must give an equivalent answer when invoked with equivalent strings.
4450
** The collating function must obey the following properties for all
4451
** strings A, B, and C:
4452
**
4453
** <ol>
4454
** <li> If A==B then B==A.
4455
** <li> If A==B and B==C then A==C.
4456
** <li> If A&lt;B THEN B&gt;A.
4457
** <li> If A&lt;B and B&lt;C then A&lt;C.
4458
** </ol>
4459
**
4460
** If a collating function fails any of the above constraints and that
4461
** collating function is  registered and used, then the behavior of SQLite
4462
** is undefined.
4463
**
4464
** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
4465
** with the addition that the xDestroy callback is invoked on pArg when
4466
** the collating function is deleted.
4467
** ^Collating functions are deleted when they are overridden by later
4468
** calls to the collation creation functions or when the
4469
** [database connection] is closed using [sqlite3_close()].
4470
**
4471
** ^The xDestroy callback is <u>not</u> called if the 
4472
** sqlite3_create_collation_v2() function fails.  Applications that invoke
4473
** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 
4474
** check the return code and dispose of the application data pointer
4475
** themselves rather than expecting SQLite to deal with it for them.
4476
** This is different from every other SQLite interface.  The inconsistency 
4477
** is unfortunate but cannot be changed without breaking backwards 
4478
** compatibility.
4479
**
4480
** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
4481
*/
4482
SQLITE_API int sqlite3_create_collation(
4483
  sqlite3*, 
4484
  const char *zName, 
4485
  int eTextRep, 
4486
  void *pArg,
4487
  int(*xCompare)(void*,int,const void*,int,const void*)
4488
);
4489
SQLITE_API int sqlite3_create_collation_v2(
4490
  sqlite3*, 
4491
  const char *zName, 
4492
  int eTextRep, 
4493
  void *pArg,
4494
  int(*xCompare)(void*,int,const void*,int,const void*),
4495
  void(*xDestroy)(void*)
4496
);
4497
SQLITE_API int sqlite3_create_collation16(
4498
  sqlite3*, 
4499
  const void *zName,
4500
  int eTextRep, 
4501
  void *pArg,
4502
  int(*xCompare)(void*,int,const void*,int,const void*)
4503
);
4504
4505
/*
4506
** CAPI3REF: Collation Needed Callbacks
4507
**
4508
** ^To avoid having to register all collation sequences before a database
4509
** can be used, a single callback function may be registered with the
4510
** [database connection] to be invoked whenever an undefined collation
4511
** sequence is required.
4512
**
4513
** ^If the function is registered using the sqlite3_collation_needed() API,
4514
** then it is passed the names of undefined collation sequences as strings
4515
** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
4516
** the names are passed as UTF-16 in machine native byte order.
4517
** ^A call to either function replaces the existing collation-needed callback.
4518
**
4519
** ^(When the callback is invoked, the first argument passed is a copy
4520
** of the second argument to sqlite3_collation_needed() or
4521
** sqlite3_collation_needed16().  The second argument is the database
4522
** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
4523
** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
4524
** sequence function required.  The fourth parameter is the name of the
4525
** required collation sequence.)^
4526
**
4527
** The callback function should register the desired collation using
4528
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
4529
** [sqlite3_create_collation_v2()].
4530
*/
4531
SQLITE_API int sqlite3_collation_needed(
4532
  sqlite3*, 
4533
  void*, 
4534
  void(*)(void*,sqlite3*,int eTextRep,const char*)
4535
);
4536
SQLITE_API int sqlite3_collation_needed16(
4537
  sqlite3*, 
4538
  void*,
4539
  void(*)(void*,sqlite3*,int eTextRep,const void*)
4540
);
4541
4542
#ifdef SQLITE_HAS_CODEC
4543
/*
4544
** Specify the key for an encrypted database.  This routine should be
4545
** called right after sqlite3_open().
4546
**
4547
** The code to implement this API is not available in the public release
4548
** of SQLite.
4549
*/
4550
SQLITE_API int sqlite3_key(
4551
  sqlite3 *db,                   /* Database to be rekeyed */
4552
  const void *pKey, int nKey     /* The key */
4553
);
4554
SQLITE_API int sqlite3_key_v2(
4555
  sqlite3 *db,                   /* Database to be rekeyed */
4556
  const char *zDbName,           /* Name of the database */
4557
  const void *pKey, int nKey     /* The key */
4558
);
4559
4560
/*
4561
** Change the key on an open database.  If the current database is not
4562
** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
4563
** database is decrypted.
4564
**
4565
** The code to implement this API is not available in the public release
4566
** of SQLite.
4567
*/
4568
SQLITE_API int sqlite3_rekey(
4569
  sqlite3 *db,                   /* Database to be rekeyed */
4570
  const void *pKey, int nKey     /* The new key */
4571
);
4572
SQLITE_API int sqlite3_rekey_v2(
4573
  sqlite3 *db,                   /* Database to be rekeyed */
4574
  const char *zDbName,           /* Name of the database */
4575
  const void *pKey, int nKey     /* The new key */
4576
);
4577
4578
/*
4579
** Specify the activation key for a SEE database.  Unless 
4580
** activated, none of the SEE routines will work.
4581
*/
4582
SQLITE_API void sqlite3_activate_see(
4583
  const char *zPassPhrase        /* Activation phrase */
4584
);
4585
#endif
4586
4587
#ifdef SQLITE_ENABLE_CEROD
4588
/*
4589
** Specify the activation key for a CEROD database.  Unless 
4590
** activated, none of the CEROD routines will work.
4591
*/
4592
SQLITE_API void sqlite3_activate_cerod(
4593
  const char *zPassPhrase        /* Activation phrase */
4594
);
4595
#endif
4596
4597
/*
4598
** CAPI3REF: Suspend Execution For A Short Time
4599
**
4600
** The sqlite3_sleep() function causes the current thread to suspend execution
4601
** for at least a number of milliseconds specified in its parameter.
4602
**
4603
** If the operating system does not support sleep requests with
4604
** millisecond time resolution, then the time will be rounded up to
4605
** the nearest second. The number of milliseconds of sleep actually
4606
** requested from the operating system is returned.
4607
**
4608
** ^SQLite implements this interface by calling the xSleep()
4609
** method of the default [sqlite3_vfs] object.  If the xSleep() method
4610
** of the default VFS is not implemented correctly, or not implemented at
4611
** all, then the behavior of sqlite3_sleep() may deviate from the description
4612
** in the previous paragraphs.
4613
*/
4614
SQLITE_API int sqlite3_sleep(int);
4615
4616
/*
4617
** CAPI3REF: Name Of The Folder Holding Temporary Files
4618
**
4619
** ^(If this global variable is made to point to a string which is
4620
** the name of a folder (a.k.a. directory), then all temporary files
4621
** created by SQLite when using a built-in [sqlite3_vfs | VFS]
4622
** will be placed in that directory.)^  ^If this variable
4623
** is a NULL pointer, then SQLite performs a search for an appropriate
4624
** temporary file directory.
4625
**
4626
** It is not safe to read or modify this variable in more than one
4627
** thread at a time.  It is not safe to read or modify this variable
4628
** if a [database connection] is being used at the same time in a separate
4629
** thread.
4630
** It is intended that this variable be set once
4631
** as part of process initialization and before any SQLite interface
4632
** routines have been called and that this variable remain unchanged
4633
** thereafter.
4634
**
4635
** ^The [temp_store_directory pragma] may modify this variable and cause
4636
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
4637
** the [temp_store_directory pragma] always assumes that any string
4638
** that this variable points to is held in memory obtained from 
4639
** [sqlite3_malloc] and the pragma may attempt to free that memory
4640
** using [sqlite3_free].
4641
** Hence, if this variable is modified directly, either it should be
4642
** made NULL or made to point to memory obtained from [sqlite3_malloc]
4643
** or else the use of the [temp_store_directory pragma] should be avoided.
4644
**
4645
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
4646
** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
4647
** features that require the use of temporary files may fail.  Here is an
4648
** example of how to do this using C++ with the Windows Runtime:
4649
**
4650
** <blockquote><pre>
4651
** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
4652
** &nbsp;     TemporaryFolder->Path->Data();
4653
** char zPathBuf&#91;MAX_PATH + 1&#93;;
4654
** memset(zPathBuf, 0, sizeof(zPathBuf));
4655
** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
4656
** &nbsp;     NULL, NULL);
4657
** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
4658
** </pre></blockquote>
4659
*/
4660
SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
4661
4662
/*
4663
** CAPI3REF: Name Of The Folder Holding Database Files
4664
**
4665
** ^(If this global variable is made to point to a string which is
4666
** the name of a folder (a.k.a. directory), then all database files
4667
** specified with a relative pathname and created or accessed by
4668
** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
4669
** to be relative to that directory.)^ ^If this variable is a NULL
4670
** pointer, then SQLite assumes that all database files specified
4671
** with a relative pathname are relative to the current directory
4672
** for the process.  Only the windows VFS makes use of this global
4673
** variable; it is ignored by the unix VFS.
4674
**
4675
** Changing the value of this variable while a database connection is
4676
** open can result in a corrupt database.
4677
**
4678
** It is not safe to read or modify this variable in more than one
4679
** thread at a time.  It is not safe to read or modify this variable
4680
** if a [database connection] is being used at the same time in a separate
4681
** thread.
4682
** It is intended that this variable be set once
4683
** as part of process initialization and before any SQLite interface
4684
** routines have been called and that this variable remain unchanged
4685
** thereafter.
4686
**
4687
** ^The [data_store_directory pragma] may modify this variable and cause
4688
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
4689
** the [data_store_directory pragma] always assumes that any string
4690
** that this variable points to is held in memory obtained from 
4691
** [sqlite3_malloc] and the pragma may attempt to free that memory
4692
** using [sqlite3_free].
4693
** Hence, if this variable is modified directly, either it should be
4694
** made NULL or made to point to memory obtained from [sqlite3_malloc]
4695
** or else the use of the [data_store_directory pragma] should be avoided.
4696
*/
4697
SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
4698
4699
/*
4700
** CAPI3REF: Test For Auto-Commit Mode
4701
** KEYWORDS: {autocommit mode}
4702
**
4703
** ^The sqlite3_get_autocommit() interface returns non-zero or
4704
** zero if the given database connection is or is not in autocommit mode,
4705
** respectively.  ^Autocommit mode is on by default.
4706
** ^Autocommit mode is disabled by a [BEGIN] statement.
4707
** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
4708
**
4709
** If certain kinds of errors occur on a statement within a multi-statement
4710
** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
4711
** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
4712
** transaction might be rolled back automatically.  The only way to
4713
** find out whether SQLite automatically rolled back the transaction after
4714
** an error is to use this function.
4715
**
4716
** If another thread changes the autocommit status of the database
4717
** connection while this routine is running, then the return value
4718
** is undefined.
4719
*/
4720
SQLITE_API int sqlite3_get_autocommit(sqlite3*);
4721
4722
/*
4723
** CAPI3REF: Find The Database Handle Of A Prepared Statement
4724
**
4725
** ^The sqlite3_db_handle interface returns the [database connection] handle
4726
** to which a [prepared statement] belongs.  ^The [database connection]
4727
** returned by sqlite3_db_handle is the same [database connection]
4728
** that was the first argument
4729
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
4730
** create the statement in the first place.
4731
*/
4732
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
4733
4734
/*
4735
** CAPI3REF: Return The Filename For A Database Connection
4736
**
4737
** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
4738
** associated with database N of connection D.  ^The main database file
4739
** has the name "main".  If there is no attached database N on the database
4740
** connection D, or if database N is a temporary or in-memory database, then
4741
** a NULL pointer is returned.
4742
**
4743
** ^The filename returned by this function is the output of the
4744
** xFullPathname method of the [VFS].  ^In other words, the filename
4745
** will be an absolute pathname, even if the filename used
4746
** to open the database originally was a URI or relative pathname.
4747
*/
4748
SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
4749
4750
/*
4751
** CAPI3REF: Determine if a database is read-only
4752
**
4753
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
4754
** of connection D is read-only, 0 if it is read/write, or -1 if N is not
4755
** the name of a database on connection D.
4756
*/
4757
SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
4758
4759
/*
4760
** CAPI3REF: Find the next prepared statement
4761
**
4762
** ^This interface returns a pointer to the next [prepared statement] after
4763
** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
4764
** then this interface returns a pointer to the first prepared statement
4765
** associated with the database connection pDb.  ^If no prepared statement
4766
** satisfies the conditions of this routine, it returns NULL.
4767
**
4768
** The [database connection] pointer D in a call to
4769
** [sqlite3_next_stmt(D,S)] must refer to an open database
4770
** connection and in particular must not be a NULL pointer.
4771
*/
4772
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
4773
4774
/*
4775
** CAPI3REF: Commit And Rollback Notification Callbacks
4776
**
4777
** ^The sqlite3_commit_hook() interface registers a callback
4778
** function to be invoked whenever a transaction is [COMMIT | committed].
4779
** ^Any callback set by a previous call to sqlite3_commit_hook()
4780
** for the same database connection is overridden.
4781
** ^The sqlite3_rollback_hook() interface registers a callback
4782
** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
4783
** ^Any callback set by a previous call to sqlite3_rollback_hook()
4784
** for the same database connection is overridden.
4785
** ^The pArg argument is passed through to the callback.
4786
** ^If the callback on a commit hook function returns non-zero,
4787
** then the commit is converted into a rollback.
4788
**
4789
** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
4790
** return the P argument from the previous call of the same function
4791
** on the same [database connection] D, or NULL for
4792
** the first call for each function on D.
4793
**
4794
** The commit and rollback hook callbacks are not reentrant.
4795
** The callback implementation must not do anything that will modify
4796
** the database connection that invoked the callback.  Any actions
4797
** to modify the database connection must be deferred until after the
4798
** completion of the [sqlite3_step()] call that triggered the commit
4799
** or rollback hook in the first place.
4800
** Note that running any other SQL statements, including SELECT statements,
4801
** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
4802
** the database connections for the meaning of "modify" in this paragraph.
4803
**
4804
** ^Registering a NULL function disables the callback.
4805
**
4806
** ^When the commit hook callback routine returns zero, the [COMMIT]
4807
** operation is allowed to continue normally.  ^If the commit hook
4808
** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
4809
** ^The rollback hook is invoked on a rollback that results from a commit
4810
** hook returning non-zero, just as it would be with any other rollback.
4811
**
4812
** ^For the purposes of this API, a transaction is said to have been
4813
** rolled back if an explicit "ROLLBACK" statement is executed, or
4814
** an error or constraint causes an implicit rollback to occur.
4815
** ^The rollback callback is not invoked if a transaction is
4816
** automatically rolled back because the database connection is closed.
4817
**
4818
** See also the [sqlite3_update_hook()] interface.
4819
*/
4820
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
4821
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
4822
4823
/*
4824
** CAPI3REF: Data Change Notification Callbacks
4825
**
4826
** ^The sqlite3_update_hook() interface registers a callback function
4827
** with the [database connection] identified by the first argument
4828
** to be invoked whenever a row is updated, inserted or deleted in
4829
** a rowid table.
4830
** ^Any callback set by a previous call to this function
4831
** for the same database connection is overridden.
4832
**
4833
** ^The second argument is a pointer to the function to invoke when a
4834
** row is updated, inserted or deleted in a rowid table.
4835
** ^The first argument to the callback is a copy of the third argument
4836
** to sqlite3_update_hook().
4837
** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
4838
** or [SQLITE_UPDATE], depending on the operation that caused the callback
4839
** to be invoked.
4840
** ^The third and fourth arguments to the callback contain pointers to the
4841
** database and table name containing the affected row.
4842
** ^The final callback parameter is the [rowid] of the row.
4843
** ^In the case of an update, this is the [rowid] after the update takes place.
4844
**
4845
** ^(The update hook is not invoked when internal system tables are
4846
** modified (i.e. sqlite_master and sqlite_sequence).)^
4847
** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
4848
**
4849
** ^In the current implementation, the update hook
4850
** is not invoked when duplication rows are deleted because of an
4851
** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
4852
** invoked when rows are deleted using the [truncate optimization].
4853
** The exceptions defined in this paragraph might change in a future
4854
** release of SQLite.
4855
**
4856
** The update hook implementation must not do anything that will modify
4857
** the database connection that invoked the update hook.  Any actions
4858
** to modify the database connection must be deferred until after the
4859
** completion of the [sqlite3_step()] call that triggered the update hook.
4860
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
4861
** database connections for the meaning of "modify" in this paragraph.
4862
**
4863
** ^The sqlite3_update_hook(D,C,P) function
4864
** returns the P argument from the previous call
4865
** on the same [database connection] D, or NULL for
4866
** the first call on D.
4867
**
4868
** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
4869
** interfaces.
4870
*/
4871
SQLITE_API void *sqlite3_update_hook(
4872
  sqlite3*, 
4873
  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
4874
  void*
4875
);
4876
4877
/*
4878
** CAPI3REF: Enable Or Disable Shared Pager Cache
4879
**
4880
** ^(This routine enables or disables the sharing of the database cache
4881
** and schema data structures between [database connection | connections]
4882
** to the same database. Sharing is enabled if the argument is true
4883
** and disabled if the argument is false.)^
4884
**
4885
** ^Cache sharing is enabled and disabled for an entire process.
4886
** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
4887
** sharing was enabled or disabled for each thread separately.
4888
**
4889
** ^(The cache sharing mode set by this interface effects all subsequent
4890
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
4891
** Existing database connections continue use the sharing mode
4892
** that was in effect at the time they were opened.)^
4893
**
4894
** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
4895
** successfully.  An [error code] is returned otherwise.)^
4896
**
4897
** ^Shared cache is disabled by default. But this might change in
4898
** future releases of SQLite.  Applications that care about shared
4899
** cache setting should set it explicitly.
4900
**
4901
** This interface is threadsafe on processors where writing a
4902
** 32-bit integer is atomic.
4903
**
4904
** See Also:  [SQLite Shared-Cache Mode]
4905
*/
4906
SQLITE_API int sqlite3_enable_shared_cache(int);
4907
4908
/*
4909
** CAPI3REF: Attempt To Free Heap Memory
4910
**
4911
** ^The sqlite3_release_memory() interface attempts to free N bytes
4912
** of heap memory by deallocating non-essential memory allocations
4913
** held by the database library.   Memory used to cache database
4914
** pages to improve performance is an example of non-essential memory.
4915
** ^sqlite3_release_memory() returns the number of bytes actually freed,
4916
** which might be more or less than the amount requested.
4917
** ^The sqlite3_release_memory() routine is a no-op returning zero
4918
** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
4919
**
4920
** See also: [sqlite3_db_release_memory()]
4921
*/
4922
SQLITE_API int sqlite3_release_memory(int);
4923
4924
/*
4925
** CAPI3REF: Free Memory Used By A Database Connection
4926
**
4927
** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
4928
** memory as possible from database connection D. Unlike the
4929
** [sqlite3_release_memory()] interface, this interface is in effect even
4930
** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
4931
** omitted.
4932
**
4933
** See also: [sqlite3_release_memory()]
4934
*/
4935
SQLITE_API int sqlite3_db_release_memory(sqlite3*);
4936
4937
/*
4938
** CAPI3REF: Impose A Limit On Heap Size
4939
**
4940
** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
4941
** soft limit on the amount of heap memory that may be allocated by SQLite.
4942
** ^SQLite strives to keep heap memory utilization below the soft heap
4943
** limit by reducing the number of pages held in the page cache
4944
** as heap memory usages approaches the limit.
4945
** ^The soft heap limit is "soft" because even though SQLite strives to stay
4946
** below the limit, it will exceed the limit rather than generate
4947
** an [SQLITE_NOMEM] error.  In other words, the soft heap limit 
4948
** is advisory only.
4949
**
4950
** ^The return value from sqlite3_soft_heap_limit64() is the size of
4951
** the soft heap limit prior to the call, or negative in the case of an
4952
** error.  ^If the argument N is negative
4953
** then no change is made to the soft heap limit.  Hence, the current
4954
** size of the soft heap limit can be determined by invoking
4955
** sqlite3_soft_heap_limit64() with a negative argument.
4956
**
4957
** ^If the argument N is zero then the soft heap limit is disabled.
4958
**
4959
** ^(The soft heap limit is not enforced in the current implementation
4960
** if one or more of following conditions are true:
4961
**
4962
** <ul>
4963
** <li> The soft heap limit is set to zero.
4964
** <li> Memory accounting is disabled using a combination of the
4965
**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
4966
**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
4967
** <li> An alternative page cache implementation is specified using
4968
**      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
4969
** <li> The page cache allocates from its own memory pool supplied
4970
**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
4971
**      from the heap.
4972
** </ul>)^
4973
**
4974
** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
4975
** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
4976
** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
4977
** the soft heap limit is enforced on every memory allocation.  Without
4978
** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
4979
** when memory is allocated by the page cache.  Testing suggests that because
4980
** the page cache is the predominate memory user in SQLite, most
4981
** applications will achieve adequate soft heap limit enforcement without
4982
** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
4983
**
4984
** The circumstances under which SQLite will enforce the soft heap limit may
4985
** changes in future releases of SQLite.
4986
*/
4987
SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
4988
4989
/*
4990
** CAPI3REF: Deprecated Soft Heap Limit Interface
4991
** DEPRECATED
4992
**
4993
** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
4994
** interface.  This routine is provided for historical compatibility
4995
** only.  All new applications should use the
4996
** [sqlite3_soft_heap_limit64()] interface rather than this one.
4997
*/
4998
SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
4999
5000
5001
/*
5002
** CAPI3REF: Extract Metadata About A Column Of A Table
5003
**
5004
** ^This routine returns metadata about a specific column of a specific
5005
** database table accessible using the [database connection] handle
5006
** passed as the first function argument.
5007
**
5008
** ^The column is identified by the second, third and fourth parameters to
5009
** this function. ^The second parameter is either the name of the database
5010
** (i.e. "main", "temp", or an attached database) containing the specified
5011
** table or NULL. ^If it is NULL, then all attached databases are searched
5012
** for the table using the same algorithm used by the database engine to
5013
** resolve unqualified table references.
5014
**
5015
** ^The third and fourth parameters to this function are the table and column
5016
** name of the desired column, respectively. Neither of these parameters
5017
** may be NULL.
5018
**
5019
** ^Metadata is returned by writing to the memory locations passed as the 5th
5020
** and subsequent parameters to this function. ^Any of these arguments may be
5021
** NULL, in which case the corresponding element of metadata is omitted.
5022
**
5023
** ^(<blockquote>
5024
** <table border="1">
5025
** <tr><th> Parameter <th> Output<br>Type <th>  Description
5026
**
5027
** <tr><td> 5th <td> const char* <td> Data type
5028
** <tr><td> 6th <td> const char* <td> Name of default collation sequence
5029
** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
5030
** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
5031
** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
5032
** </table>
5033
** </blockquote>)^
5034
**
5035
** ^The memory pointed to by the character pointers returned for the
5036
** declaration type and collation sequence is valid only until the next
5037
** call to any SQLite API function.
5038
**
5039
** ^If the specified table is actually a view, an [error code] is returned.
5040
**
5041
** ^If the specified column is "rowid", "oid" or "_rowid_" and an
5042
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
5043
** parameters are set for the explicitly declared column. ^(If there is no
5044
** explicitly declared [INTEGER PRIMARY KEY] column, then the output
5045
** parameters are set as follows:
5046
**
5047
** <pre>
5048
**     data type: "INTEGER"
5049
**     collation sequence: "BINARY"
5050
**     not null: 0
5051
**     primary key: 1
5052
**     auto increment: 0
5053
** </pre>)^
5054
**
5055
** ^(This function may load one or more schemas from database files. If an
5056
** error occurs during this process, or if the requested table or column
5057
** cannot be found, an [error code] is returned and an error message left
5058
** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
5059
**
5060
** ^This API is only available if the library was compiled with the
5061
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
5062
*/
5063
SQLITE_API int sqlite3_table_column_metadata(
5064
  sqlite3 *db,                /* Connection handle */
5065
  const char *zDbName,        /* Database name or NULL */
5066
  const char *zTableName,     /* Table name */
5067
  const char *zColumnName,    /* Column name */
5068
  char const **pzDataType,    /* OUTPUT: Declared data type */
5069
  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
5070
  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
5071
  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
5072
  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
5073
);
5074
5075
/*
5076
** CAPI3REF: Load An Extension
5077
**
5078
** ^This interface loads an SQLite extension library from the named file.
5079
**
5080
** ^The sqlite3_load_extension() interface attempts to load an
5081
** [SQLite extension] library contained in the file zFile.  If
5082
** the file cannot be loaded directly, attempts are made to load
5083
** with various operating-system specific extensions added.
5084
** So for example, if "samplelib" cannot be loaded, then names like
5085
** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
5086
** be tried also.
5087
**
5088
** ^The entry point is zProc.
5089
** ^(zProc may be 0, in which case SQLite will try to come up with an
5090
** entry point name on its own.  It first tries "sqlite3_extension_init".
5091
** If that does not work, it constructs a name "sqlite3_X_init" where the
5092
** X is consists of the lower-case equivalent of all ASCII alphabetic
5093
** characters in the filename from the last "/" to the first following
5094
** "." and omitting any initial "lib".)^
5095
** ^The sqlite3_load_extension() interface returns
5096
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
5097
** ^If an error occurs and pzErrMsg is not 0, then the
5098
** [sqlite3_load_extension()] interface shall attempt to
5099
** fill *pzErrMsg with error message text stored in memory
5100
** obtained from [sqlite3_malloc()]. The calling function
5101
** should free this memory by calling [sqlite3_free()].
5102
**
5103
** ^Extension loading must be enabled using
5104
** [sqlite3_enable_load_extension()] prior to calling this API,
5105
** otherwise an error will be returned.
5106
**
5107
** See also the [load_extension() SQL function].
5108
*/
5109
SQLITE_API int sqlite3_load_extension(
5110
  sqlite3 *db,          /* Load the extension into this database connection */
5111
  const char *zFile,    /* Name of the shared library containing extension */
5112
  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
5113
  char **pzErrMsg       /* Put error message here if not 0 */
5114
);
5115
5116
/*
5117
** CAPI3REF: Enable Or Disable Extension Loading
5118
**
5119
** ^So as not to open security holes in older applications that are
5120
** unprepared to deal with [extension loading], and as a means of disabling
5121
** [extension loading] while evaluating user-entered SQL, the following API
5122
** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
5123
**
5124
** ^Extension loading is off by default.
5125
** ^Call the sqlite3_enable_load_extension() routine with onoff==1
5126
** to turn extension loading on and call it with onoff==0 to turn
5127
** it back off again.
5128
*/
5129
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
5130
5131
/*
5132
** CAPI3REF: Automatically Load Statically Linked Extensions
5133
**
5134
** ^This interface causes the xEntryPoint() function to be invoked for
5135
** each new [database connection] that is created.  The idea here is that
5136
** xEntryPoint() is the entry point for a statically linked [SQLite extension]
5137
** that is to be automatically loaded into all new database connections.
5138
**
5139
** ^(Even though the function prototype shows that xEntryPoint() takes
5140
** no arguments and returns void, SQLite invokes xEntryPoint() with three
5141
** arguments and expects and integer result as if the signature of the
5142
** entry point where as follows:
5143
**
5144
** <blockquote><pre>
5145
** &nbsp;  int xEntryPoint(
5146
** &nbsp;    sqlite3 *db,
5147
** &nbsp;    const char **pzErrMsg,
5148
** &nbsp;    const struct sqlite3_api_routines *pThunk
5149
** &nbsp;  );
5150
** </pre></blockquote>)^
5151
**
5152
** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
5153
** point to an appropriate error message (obtained from [sqlite3_mprintf()])
5154
** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
5155
** is NULL before calling the xEntryPoint().  ^SQLite will invoke
5156
** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
5157
** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
5158
** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
5159
**
5160
** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
5161
** on the list of automatic extensions is a harmless no-op. ^No entry point
5162
** will be called more than once for each database connection that is opened.
5163
**
5164
** See also: [sqlite3_reset_auto_extension()]
5165
** and [sqlite3_cancel_auto_extension()]
5166
*/
5167
SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
5168
5169
/*
5170
** CAPI3REF: Cancel Automatic Extension Loading
5171
**
5172
** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
5173
** initialization routine X that was registered using a prior call to
5174
** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
5175
** routine returns 1 if initialization routine X was successfully 
5176
** unregistered and it returns 0 if X was not on the list of initialization
5177
** routines.
5178
*/
5179
SQLITE_API int sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
5180
5181
/*
5182
** CAPI3REF: Reset Automatic Extension Loading
5183
**
5184
** ^This interface disables all automatic extensions previously
5185
** registered using [sqlite3_auto_extension()].
5186
*/
5187
SQLITE_API void sqlite3_reset_auto_extension(void);
5188
5189
/*
5190
** The interface to the virtual-table mechanism is currently considered
5191
** to be experimental.  The interface might change in incompatible ways.
5192
** If this is a problem for you, do not use the interface at this time.
5193
**
5194
** When the virtual-table mechanism stabilizes, we will declare the
5195
** interface fixed, support it indefinitely, and remove this comment.
5196
*/
5197
5198
/*
5199
** Structures used by the virtual table interface
5200
*/
5201
typedef struct sqlite3_vtab sqlite3_vtab;
5202
typedef struct sqlite3_index_info sqlite3_index_info;
5203
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
5204
typedef struct sqlite3_module sqlite3_module;
5205
5206
/*
5207
** CAPI3REF: Virtual Table Object
5208
** KEYWORDS: sqlite3_module {virtual table module}
5209
**
5210
** This structure, sometimes called a "virtual table module", 
5211
** defines the implementation of a [virtual tables].  
5212
** This structure consists mostly of methods for the module.
5213
**
5214
** ^A virtual table module is created by filling in a persistent
5215
** instance of this structure and passing a pointer to that instance
5216
** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
5217
** ^The registration remains valid until it is replaced by a different
5218
** module or until the [database connection] closes.  The content
5219
** of this structure must not change while it is registered with
5220
** any database connection.
5221
*/
5222
struct sqlite3_module {
5223
  int iVersion;
5224
  int (*xCreate)(sqlite3*, void *pAux,
5225
               int argc, const char *const*argv,
5226
               sqlite3_vtab **ppVTab, char**);
5227
  int (*xConnect)(sqlite3*, void *pAux,
5228
               int argc, const char *const*argv,
5229
               sqlite3_vtab **ppVTab, char**);
5230
  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
5231
  int (*xDisconnect)(sqlite3_vtab *pVTab);
5232
  int (*xDestroy)(sqlite3_vtab *pVTab);
5233
  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
5234
  int (*xClose)(sqlite3_vtab_cursor*);
5235
  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
5236
                int argc, sqlite3_value **argv);
5237
  int (*xNext)(sqlite3_vtab_cursor*);