1/******************************************************************************
2** This file is an amalgamation of many separate C source files from SQLite
3** version 3.43.1. By combining all the individual C code files into this
4** single large file, the entire code can be compiled as a single translation
5** unit. This allows many compilers to do optimizations that would not be
6** possible if the files were compiled separately. Performance improvements
7** of 5% or more are commonly seen when SQLite is compiled as a single
8** translation unit.
9**
10** This file is all you need to compile SQLite. To use SQLite in other
11** programs, you need this file and the "sqlite3.h" header file that defines
12** the programming interface to the SQLite library. (If you do not have
13** the "sqlite3.h" header file at hand, you will find a copy embedded within
14** the text of this file. Search for "Begin file sqlite3.h" to find the start
15** of the embedded sqlite3.h header file.) Additional code files may be needed
16** if you want a wrapper to interface SQLite with your choice of programming
17** language. The code for the "sqlite3" command-line shell is also in a
18** separate file. This file contains only code for the core SQLite library.
19**
20** The content in this amalgamation comes from Fossil check-in
21** d3a40c05c49e1a49264912b1a05bc2143ac.
22*/
23#define SQLITE_CORE 1
24#define SQLITE_AMALGAMATION 1
25#ifndef SQLITE_PRIVATE
26# define SQLITE_PRIVATE static
27#endif
28/************** Begin file sqliteInt.h ***************************************/
29/*
30** 2001 September 15
31**
32** The author disclaims copyright to this source code. In place of
33** a legal notice, here is a blessing:
34**
35** May you do good and not evil.
36** May you find forgiveness for yourself and forgive others.
37** May you share freely, never taking more than you give.
38**
39*************************************************************************
40** Internal interface definitions for SQLite.
41**
42*/
43#ifndef SQLITEINT_H
44#define SQLITEINT_H
45
46/* Special Comments:
47**
48** Some comments have special meaning to the tools that measure test
49** coverage:
50**
51** NO_TEST - The branches on this line are not
52** measured by branch coverage. This is
53** used on lines of code that actually
54** implement parts of coverage testing.
55**
56** OPTIMIZATION-IF-TRUE - This branch is allowed to always be false
57** and the correct answer is still obtained,
58** though perhaps more slowly.
59**
60** OPTIMIZATION-IF-FALSE - This branch is allowed to always be true
61** and the correct answer is still obtained,
62** though perhaps more slowly.
63**
64** PREVENTS-HARMLESS-OVERREAD - This branch prevents a buffer overread
65** that would be harmless and undetectable
66** if it did occur.
67**
68** In all cases, the special comment must be enclosed in the usual
69** slash-asterisk...asterisk-slash comment marks, with no spaces between the
70** asterisks and the comment text.
71*/
72
73/*
74** Make sure the Tcl calling convention macro is defined. This macro is
75** only used by test code and Tcl integration code.
76*/
77#ifndef SQLITE_TCLAPI
78# define SQLITE_TCLAPI
79#endif
80
81/*
82** Include the header file used to customize the compiler options for MSVC.
83** This should be done first so that it can successfully prevent spurious
84** compiler warnings due to subsequent content in this file and other files
85** that are included by this file.
86*/
87/************** Include msvc.h in the middle of sqliteInt.h ******************/
88/************** Begin file msvc.h ********************************************/
89/*
90** 2015 January 12
91**
92** The author disclaims copyright to this source code. In place of
93** a legal notice, here is a blessing:
94**
95** May you do good and not evil.
96** May you find forgiveness for yourself and forgive others.
97** May you share freely, never taking more than you give.
98**
99******************************************************************************
100**
101** This file contains code that is specific to MSVC.
102*/
103#ifndef SQLITE_MSVC_H
104#define SQLITE_MSVC_H
105
106#if defined(_MSC_VER)
107#pragma warning(disable : 4054)
108#pragma warning(disable : 4055)
109#pragma warning(disable : 4100)
110#pragma warning(disable : 4127)
111#pragma warning(disable : 4130)
112#pragma warning(disable : 4152)
113#pragma warning(disable : 4189)
114#pragma warning(disable : 4206)
115#pragma warning(disable : 4210)
116#pragma warning(disable : 4232)
117#pragma warning(disable : 4244)
118#pragma warning(disable : 4305)
119#pragma warning(disable : 4306)
120#pragma warning(disable : 4702)
121#pragma warning(disable : 4706)
122#endif /* defined(_MSC_VER) */
123
124#if defined(_MSC_VER) && !defined(_WIN64)
125#undef SQLITE_4_BYTE_ALIGNED_MALLOC
126#define SQLITE_4_BYTE_ALIGNED_MALLOC
127#endif /* defined(_MSC_VER) && !defined(_WIN64) */
128
129#if !defined(HAVE_LOG2) && defined(_MSC_VER) && _MSC_VER<1800
130#define HAVE_LOG2 0
131#endif /* !defined(HAVE_LOG2) && defined(_MSC_VER) && _MSC_VER<1800 */
132
133#endif /* SQLITE_MSVC_H */
134
135/************** End of msvc.h ************************************************/
136/************** Continuing where we left off in sqliteInt.h ******************/
137
138/*
139** Special setup for VxWorks
140*/
141/************** Include vxworks.h in the middle of sqliteInt.h ***************/
142/************** Begin file vxworks.h *****************************************/
143/*
144** 2015-03-02
145**
146** The author disclaims copyright to this source code. In place of
147** a legal notice, here is a blessing:
148**
149** May you do good and not evil.
150** May you find forgiveness for yourself and forgive others.
151** May you share freely, never taking more than you give.
152**
153******************************************************************************
154**
155** This file contains code that is specific to Wind River's VxWorks
156*/
157#if defined(__RTP__) || defined(_WRS_KERNEL)
158/* This is VxWorks. Set up things specially for that OS
159*/
160#include <vxWorks.h>
161#include <pthread.h> /* amalgamator: dontcache */
162#define OS_VXWORKS 1
163#define SQLITE_OS_OTHER 0
164#define SQLITE_HOMEGROWN_RECURSIVE_MUTEX 1
165#define SQLITE_OMIT_LOAD_EXTENSION 1
166#define SQLITE_ENABLE_LOCKING_STYLE 0
167#define HAVE_UTIME 1
168#else
169/* This is not VxWorks. */
170#define OS_VXWORKS 0
171#define HAVE_FCHOWN 1
172#define HAVE_READLINK 1
173#define HAVE_LSTAT 1
174#endif /* defined(_WRS_KERNEL) */
175
176/************** End of vxworks.h *********************************************/
177/************** Continuing where we left off in sqliteInt.h ******************/
178
179/*
180** These #defines should enable >2GB file support on POSIX if the
181** underlying operating system supports it. If the OS lacks
182** large file support, or if the OS is windows, these should be no-ops.
183**
184** Ticket #2739: The _LARGEFILE_SOURCE macro must appear before any
185** system #includes. Hence, this block of code must be the very first
186** code in all source files.
187**
188** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
189** on the compiler command line. This is necessary if you are compiling
190** on a recent machine (ex: Red Hat 7.2) but you want your code to work
191** on an older machine (ex: Red Hat 6.0). If you compile on Red Hat 7.2
192** without this option, LFS is enable. But LFS does not exist in the kernel
193** in Red Hat 6.0, so the code won't work. Hence, for maximum binary
194** portability you should omit LFS.
195**
196** The previous paragraph was written in 2005. (This paragraph is written
197** on 2008-11-28.) These days, all Linux kernels support large files, so
198** you should probably leave LFS enabled. But some embedded platforms might
199** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
200**
201** Similar is true for Mac OS X. LFS is only supported on Mac OS X 9 and later.
202*/
203#ifndef SQLITE_DISABLE_LFS
204# define _LARGE_FILE 1
205# ifndef _FILE_OFFSET_BITS
206# define _FILE_OFFSET_BITS 64
207# endif
208# define _LARGEFILE_SOURCE 1
209#endif
210
211/* The GCC_VERSION and MSVC_VERSION macros are used to
212** conditionally include optimizations for each of these compilers. A
213** value of 0 means that compiler is not being used. The
214** SQLITE_DISABLE_INTRINSIC macro means do not use any compiler-specific
215** optimizations, and hence set all compiler macros to 0
216**
217** There was once also a CLANG_VERSION macro. However, we learn that the
218** version numbers in clang are for "marketing" only and are inconsistent
219** and unreliable. Fortunately, all versions of clang also recognize the
220** gcc version numbers and have reasonable settings for gcc version numbers,
221** so the GCC_VERSION macro will be set to a correct non-zero value even
222** when compiling with clang.
223*/
224#if defined(__GNUC__) && !defined(SQLITE_DISABLE_INTRINSIC)
225# define GCC_VERSION (__GNUC__*1000000+__GNUC_MINOR__*1000+__GNUC_PATCHLEVEL__)
226#else
227# define GCC_VERSION 0
228#endif
229#if defined(_MSC_VER) && !defined(SQLITE_DISABLE_INTRINSIC)
230# define MSVC_VERSION _MSC_VER
231#else
232# define MSVC_VERSION 0
233#endif
234
235/*
236** Some C99 functions in "math.h" are only present for MSVC when its version
237** is associated with Visual Studio 2013 or higher.
238*/
239#ifndef SQLITE_HAVE_C99_MATH_FUNCS
240# if MSVC_VERSION==0 || MSVC_VERSION>=1800
241# define SQLITE_HAVE_C99_MATH_FUNCS (1)
242# else
243# define SQLITE_HAVE_C99_MATH_FUNCS (0)
244# endif
245#endif
246
247/* Needed for various definitions... */
248#if defined(__GNUC__) && !defined(_GNU_SOURCE)
249# define _GNU_SOURCE
250#endif
251
252#if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
253# define _BSD_SOURCE
254#endif
255
256/*
257** Macro to disable warnings about missing "break" at the end of a "case".
258*/
259#if GCC_VERSION>=7000000
260# define deliberate_fall_through __attribute__((fallthrough));
261#else
262# define deliberate_fall_through
263#endif
264
265/*
266** For MinGW, check to see if we can include the header file containing its
267** version information, among other things. Normally, this internal MinGW
268** header file would [only] be included automatically by other MinGW header
269** files; however, the contained version information is now required by this
270** header file to work around binary compatibility issues (see below) and
271** this is the only known way to reliably obtain it. This entire #if block
272** would be completely unnecessary if there was any other way of detecting
273** MinGW via their preprocessor (e.g. if they customized their GCC to define
274** some MinGW-specific macros). When compiling for MinGW, either the
275** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
276** defined; otherwise, detection of conditions specific to MinGW will be
277** disabled.
278*/
279#if defined(_HAVE_MINGW_H)
280# include "mingw.h"
281#elif defined(_HAVE__MINGW_H)
282# include "_mingw.h"
283#endif
284
285/*
286** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
287** define is required to maintain binary compatibility with the MSVC runtime
288** library in use (e.g. for Windows XP).
289*/
290#if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
291 defined(_WIN32) && !defined(_WIN64) && \
292 defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
293 defined(__MSVCRT__)
294# define _USE_32BIT_TIME_T
295#endif
296
297/* Optionally #include a user-defined header, whereby compilation options
298** may be set prior to where they take effect, but after platform setup.
299** If SQLITE_CUSTOM_INCLUDE=? is defined, its value names the #include
300** file.
301*/
302#ifdef SQLITE_CUSTOM_INCLUDE
303# define INC_STRINGIFY_(f) #f
304# define INC_STRINGIFY(f) INC_STRINGIFY_(f)
305# include INC_STRINGIFY(SQLITE_CUSTOM_INCLUDE)
306#endif
307
308/* The public SQLite interface. The _FILE_OFFSET_BITS macro must appear
309** first in QNX. Also, the _USE_32BIT_TIME_T macro must appear first for
310** MinGW.
311*/
312/************** Include sqlite3.h in the middle of sqliteInt.h ***************/
313/************** Begin file sqlite3.h *****************************************/
314/*
315** 2001-09-15
316**
317** The author disclaims copyright to this source code. In place of
318** a legal notice, here is a blessing:
319**
320** May you do good and not evil.
321** May you find forgiveness for yourself and forgive others.
322** May you share freely, never taking more than you give.
323**
324*************************************************************************
325** This header file defines the interface that the SQLite library
326** presents to client programs. If a C-function, structure, datatype,
327** or constant definition does not appear in this file, then it is
328** not a published API of SQLite, is subject to change without
329** notice, and should not be referenced by programs that use SQLite.
330**
331** Some of the definitions that are in this file are marked as
332** "experimental". Experimental interfaces are normally new
333** features recently added to SQLite. We do not anticipate changes
334** to experimental interfaces but reserve the right to make minor changes
335** if experience from use "in the wild" suggest such changes are prudent.
336**
337** The official C-language API documentation for SQLite is derived
338** from comments in this file. This file is the authoritative source
339** on how SQLite interfaces are supposed to operate.
340**
341** The name of this file under configuration management is "sqlite.h.in".
342** The makefile makes some minor changes to this file (such as inserting
343** the version number) and changes its name to "sqlite3.h" as
344** part of the build process.
345*/
346#ifndef SQLITE3_H
347#define SQLITE3_H
348#include <stdarg.h> /* Needed for the definition of va_list */
349
350/*
351** Make sure we can call this stuff from C++.
352*/
353#if 0
354extern "C" {
355#endif
356
357
358/*
359** Facilitate override of interface linkage and calling conventions.
360** Be aware that these macros may not be used within this particular
361** translation of the amalgamation and its associated header file.
362**
363** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the
364** compiler that the target identifier should have external linkage.
365**
366** The SQLITE_CDECL macro is used to set the calling convention for
367** public functions that accept a variable number of arguments.
368**
369** The SQLITE_APICALL macro is used to set the calling convention for
370** public functions that accept a fixed number of arguments.
371**
372** The SQLITE_STDCALL macro is no longer used and is now deprecated.
373**
374** The SQLITE_CALLBACK macro is used to set the calling convention for
375** function pointers.
376**
377** The SQLITE_SYSAPI macro is used to set the calling convention for
378** functions provided by the operating system.
379**
380** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and
381** SQLITE_SYSAPI macros are used only when building for environments
382** that require non-default calling conventions.
383*/
384#ifndef SQLITE_EXTERN
385# define SQLITE_EXTERN extern
386#endif
387#ifndef SQLITE_API
388# define SQLITE_API
389#endif
390#ifndef SQLITE_CDECL
391# define SQLITE_CDECL
392#endif
393#ifndef SQLITE_APICALL
394# define SQLITE_APICALL
395#endif
396#ifndef SQLITE_STDCALL
397# define SQLITE_STDCALL SQLITE_APICALL
398#endif
399#ifndef SQLITE_CALLBACK
400# define SQLITE_CALLBACK
401#endif
402#ifndef SQLITE_SYSAPI
403# define SQLITE_SYSAPI
404#endif
405
406/*
407** These no-op macros are used in front of interfaces to mark those
408** interfaces as either deprecated or experimental. New applications
409** should not use deprecated interfaces - they are supported for backwards
410** compatibility only. Application writers should be aware that
411** experimental interfaces are subject to change in point releases.
412**
413** These macros used to resolve to various kinds of compiler magic that
414** would generate warning messages when they were used. But that
415** compiler magic ended up generating such a flurry of bug reports
416** that we have taken it all out and gone back to using simple
417** noop macros.
418*/
419#define SQLITE_DEPRECATED
420#define SQLITE_EXPERIMENTAL
421
422/*
423** Ensure these symbols were not defined by some previous header file.
424*/
425#ifdef SQLITE_VERSION
426# undef SQLITE_VERSION
427#endif
428#ifdef SQLITE_VERSION_NUMBER
429# undef SQLITE_VERSION_NUMBER
430#endif
431
432/*
433** CAPI3REF: Compile-Time Library Version Numbers
434**
435** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
436** evaluates to a string literal that is the SQLite version in the
437** format "X.Y.Z" where X is the major version number (always 3 for
438** SQLite3) and Y is the minor version number and Z is the release number.)^
439** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
440** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
441** numbers used in [SQLITE_VERSION].)^
442** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
443** be larger than the release from which it is derived. Either Y will
444** be held constant and Z will be incremented or else Y will be incremented
445** and Z will be reset to zero.
446**
447** Since [version 3.6.18] ([dateof:3.6.18]),
448** SQLite source code has been stored in the
449** <a href="http://www.fossil-scm.org/">Fossil configuration management
450** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
451** a string which identifies a particular check-in of SQLite
452** within its configuration management system. ^The SQLITE_SOURCE_ID
453** string contains the date and time of the check-in (UTC) and a SHA1
454** or SHA3-256 hash of the entire source tree. If the source code has
455** been edited in any way since it was last checked in, then the last
456** four hexadecimal digits of the hash may be modified.
457**
458** See also: [sqlite3_libversion()],
459** [sqlite3_libversion_number()], [sqlite3_sourceid()],
460** [sqlite_version()] and [sqlite_source_id()].
461*/
462#define SQLITE_VERSION "3.43.1"
463#define SQLITE_VERSION_NUMBER 3043001
464#define SQLITE_SOURCE_ID "2023-09-11 12:01:27 2d3a40c05c49e1a49264912b1a05bc2143ac0e7c3df588276ce80a4cbc9bd1b0"
465
466/*
467** CAPI3REF: Run-Time Library Version Numbers
468** KEYWORDS: sqlite3_version sqlite3_sourceid
469**
470** These interfaces provide the same information as the [SQLITE_VERSION],
471** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
472** but are associated with the library instead of the header file. ^(Cautious
473** programmers might include assert() statements in their application to
474** verify that values returned by these interfaces match the macros in
475** the header, and thus ensure that the application is
476** compiled with matching library and header files.
477**
478** <blockquote><pre>
479** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
480** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
481** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
482** </pre></blockquote>)^
483**
484** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
485** macro. ^The sqlite3_libversion() function returns a pointer to the
486** to the sqlite3_version[] string constant. The sqlite3_libversion()
487** function is provided for use in DLLs since DLL users usually do not have
488** direct access to string constants within the DLL. ^The
489** sqlite3_libversion_number() function returns an integer equal to
490** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns
491** a pointer to a string constant whose value is the same as the
492** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built
493** using an edited copy of [the amalgamation], then the last four characters
494** of the hash might be different from [SQLITE_SOURCE_ID].)^
495**
496** See also: [sqlite_version()] and [sqlite_source_id()].
497*/
498SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
499SQLITE_API const char *sqlite3_libversion(void);
500SQLITE_API const char *sqlite3_sourceid(void);
501SQLITE_API int sqlite3_libversion_number(void);
502
503/*
504** CAPI3REF: Run-Time Library Compilation Options Diagnostics
505**
506** ^The sqlite3_compileoption_used() function returns 0 or 1
507** indicating whether the specified option was defined at
508** compile time. ^The SQLITE_ prefix may be omitted from the
509** option name passed to sqlite3_compileoption_used().
510**
511** ^The sqlite3_compileoption_get() function allows iterating
512** over the list of options that were defined at compile time by
513** returning the N-th compile time option string. ^If N is out of range,
514** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
515** prefix is omitted from any strings returned by
516** sqlite3_compileoption_get().
517**
518** ^Support for the diagnostic functions sqlite3_compileoption_used()
519** and sqlite3_compileoption_get() may be omitted by specifying the
520** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
521**
522** See also: SQL functions [sqlite_compileoption_used()] and
523** [sqlite_compileoption_get()] and the [compile_options pragma].
524*/
525#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
526SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
527SQLITE_API const char *sqlite3_compileoption_get(int N);
528#else
529# define sqlite3_compileoption_used(X) 0
530# define sqlite3_compileoption_get(X) ((void*)0)
531#endif
532
533/*
534** CAPI3REF: Test To See If The Library Is Threadsafe
535**
536** ^The sqlite3_threadsafe() function returns zero if and only if
537** SQLite was compiled with mutexing code omitted due to the
538** [SQLITE_THREADSAFE] compile-time option being set to 0.
539**
540** SQLite can be compiled with or without mutexes. When
541** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
542** are enabled and SQLite is threadsafe. When the
543** [SQLITE_THREADSAFE] macro is 0,
544** the mutexes are omitted. Without the mutexes, it is not safe
545** to use SQLite concurrently from more than one thread.
546**
547** Enabling mutexes incurs a measurable performance penalty.
548** So if speed is of utmost importance, it makes sense to disable
549** the mutexes. But for maximum safety, mutexes should be enabled.
550** ^The default behavior is for mutexes to be enabled.
551**
552** This interface can be used by an application to make sure that the
553** version of SQLite that it is linking against was compiled with
554** the desired setting of the [SQLITE_THREADSAFE] macro.
555**
556** This interface only reports on the compile-time mutex setting
557** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
558** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
559** can be fully or partially disabled using a call to [sqlite3_config()]
560** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
561** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the
562** sqlite3_threadsafe() function shows only the compile-time setting of
563** thread safety, not any run-time changes to that setting made by
564** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
565** is unchanged by calls to sqlite3_config().)^
566**
567** See the [threading mode] documentation for additional information.
568*/
569SQLITE_API int sqlite3_threadsafe(void);
570
571/*
572** CAPI3REF: Database Connection Handle
573** KEYWORDS: {database connection} {database connections}
574**
575** Each open SQLite database is represented by a pointer to an instance of
576** the opaque structure named "sqlite3". It is useful to think of an sqlite3
577** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
578** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
579** and [sqlite3_close_v2()] are its destructors. There are many other
580** interfaces (such as
581** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
582** [sqlite3_busy_timeout()] to name but three) that are methods on an
583** sqlite3 object.
584*/
585typedef struct sqlite3 sqlite3;
586
587/*
588** CAPI3REF: 64-Bit Integer Types
589** KEYWORDS: sqlite_int64 sqlite_uint64
590**
591** Because there is no cross-platform way to specify 64-bit integer types
592** SQLite includes typedefs for 64-bit signed and unsigned integers.
593**
594** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
595** The sqlite_int64 and sqlite_uint64 types are supported for backwards
596** compatibility only.
597**
598** ^The sqlite3_int64 and sqlite_int64 types can store integer values
599** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
600** sqlite3_uint64 and sqlite_uint64 types can store integer values
601** between 0 and +18446744073709551615 inclusive.
602*/
603#ifdef SQLITE_INT64_TYPE
604 typedef SQLITE_INT64_TYPE sqlite_int64;
605# ifdef SQLITE_UINT64_TYPE
606 typedef SQLITE_UINT64_TYPE sqlite_uint64;
607# else
608 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
609# endif
610#elif defined(_MSC_VER) || defined(__BORLANDC__)
611 typedef __int64 sqlite_int64;
612 typedef unsigned __int64 sqlite_uint64;
613#else
614 typedef long long int sqlite_int64;
615 typedef unsigned long long int sqlite_uint64;
616#endif
617typedef sqlite_int64 sqlite3_int64;
618typedef sqlite_uint64 sqlite3_uint64;
619
620/*
621** If compiling for a processor that lacks floating point support,
622** substitute integer for floating-point.
623*/
624#ifdef SQLITE_OMIT_FLOATING_POINT
625# define double sqlite3_int64
626#endif
627
628/*
629** CAPI3REF: Closing A Database Connection
630** DESTRUCTOR: sqlite3
631**
632** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
633** for the [sqlite3] object.
634** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
635** the [sqlite3] object is successfully destroyed and all associated
636** resources are deallocated.
637**
638** Ideally, applications should [sqlite3_finalize | finalize] all
639** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
640** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
641** with the [sqlite3] object prior to attempting to close the object.
642** ^If the database connection is associated with unfinalized prepared
643** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
644** sqlite3_close() will leave the database connection open and return
645** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
646** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
647** it returns [SQLITE_OK] regardless, but instead of deallocating the database
648** connection immediately, it marks the database connection as an unusable
649** "zombie" and makes arrangements to automatically deallocate the database
650** connection after all prepared statements are finalized, all BLOB handles
651** are closed, and all backups have finished. The sqlite3_close_v2() interface
652** is intended for use with host languages that are garbage collected, and
653** where the order in which destructors are called is arbitrary.
654**
655** ^If an [sqlite3] object is destroyed while a transaction is open,
656** the transaction is automatically rolled back.
657**
658** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
659** must be either a NULL
660** pointer or an [sqlite3] object pointer obtained
661** from [sqlite3_open()], [sqlite3_open16()], or
662** [sqlite3_open_v2()], and not previously closed.
663** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
664** argument is a harmless no-op.
665*/
666SQLITE_API int sqlite3_close(sqlite3*);
667SQLITE_API int sqlite3_close_v2(sqlite3*);
668
669/*
670** The type for a callback function.
671** This is legacy and deprecated. It is included for historical
672** compatibility and is not documented.
673*/
674typedef int (*sqlite3_callback)(void*,int,char**, char**);
675
676/*
677** CAPI3REF: One-Step Query Execution Interface
678** METHOD: sqlite3
679**
680** The sqlite3_exec() interface is a convenience wrapper around
681** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
682** that allows an application to run multiple statements of SQL
683** without having to use a lot of C code.
684**
685** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
686** semicolon-separate SQL statements passed into its 2nd argument,
687** in the context of the [database connection] passed in as its 1st
688** argument. ^If the callback function of the 3rd argument to
689** sqlite3_exec() is not NULL, then it is invoked for each result row
690** coming out of the evaluated SQL statements. ^The 4th argument to
691** sqlite3_exec() is relayed through to the 1st argument of each
692** callback invocation. ^If the callback pointer to sqlite3_exec()
693** is NULL, then no callback is ever invoked and result rows are
694** ignored.
695**
696** ^If an error occurs while evaluating the SQL statements passed into
697** sqlite3_exec(), then execution of the current statement stops and
698** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
699** is not NULL then any error message is written into memory obtained
700** from [sqlite3_malloc()] and passed back through the 5th parameter.
701** To avoid memory leaks, the application should invoke [sqlite3_free()]
702** on error message strings returned through the 5th parameter of
703** sqlite3_exec() after the error message string is no longer needed.
704** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
705** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
706** NULL before returning.
707**
708** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
709** routine returns SQLITE_ABORT without invoking the callback again and
710** without running any subsequent SQL statements.
711**
712** ^The 2nd argument to the sqlite3_exec() callback function is the
713** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
714** callback is an array of pointers to strings obtained as if from
715** [sqlite3_column_text()], one for each column. ^If an element of a
716** result row is NULL then the corresponding string pointer for the
717** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
718** sqlite3_exec() callback is an array of pointers to strings where each
719** entry represents the name of corresponding result column as obtained
720** from [sqlite3_column_name()].
721**
722** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
723** to an empty string, or a pointer that contains only whitespace and/or
724** SQL comments, then no SQL statements are evaluated and the database
725** is not changed.
726**
727** Restrictions:
728**
729** <ul>
730** <li> The application must ensure that the 1st parameter to sqlite3_exec()
731** is a valid and open [database connection].
732** <li> The application must not close the [database connection] specified by
733** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
734** <li> The application must not modify the SQL statement text passed into
735** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
736** </ul>
737*/
738SQLITE_API int sqlite3_exec(
739 sqlite3*, /* An open database */
740 const char *sql, /* SQL to be evaluated */
741 int (*callback)(void*,int,char**,char**), /* Callback function */
742 void *, /* 1st argument to callback */
743 char **errmsg /* Error msg written here */
744);
745
746/*
747** CAPI3REF: Result Codes
748** KEYWORDS: {result code definitions}
749**
750** Many SQLite functions return an integer result code from the set shown
751** here in order to indicate success or failure.
752**
753** New error codes may be added in future versions of SQLite.
754**
755** See also: [extended result code definitions]
756*/
757#define SQLITE_OK 0 /* Successful result */
758/* beginning-of-error-codes */
759#define SQLITE_ERROR 1 /* Generic error */
760#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
761#define SQLITE_PERM 3 /* Access permission denied */
762#define SQLITE_ABORT 4 /* Callback routine requested an abort */
763#define SQLITE_BUSY 5 /* The database file is locked */
764#define SQLITE_LOCKED 6 /* A table in the database is locked */
765#define SQLITE_NOMEM 7 /* A malloc() failed */
766#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
767#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
768#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
769#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
770#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
771#define SQLITE_FULL 13 /* Insertion failed because database is full */
772#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
773#define SQLITE_PROTOCOL 15 /* Database lock protocol error */
774#define SQLITE_EMPTY 16 /* Internal use only */
775#define SQLITE_SCHEMA 17 /* The database schema changed */
776#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
777#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
778#define SQLITE_MISMATCH 20 /* Data type mismatch */
779#define SQLITE_MISUSE 21 /* Library used incorrectly */
780#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
781#define SQLITE_AUTH 23 /* Authorization denied */
782#define SQLITE_FORMAT 24 /* Not used */
783#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
784#define SQLITE_NOTADB 26 /* File opened that is not a database file */
785#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
786#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
787#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
788#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
789/* end-of-error-codes */
790
791/*
792** CAPI3REF: Extended Result Codes
793** KEYWORDS: {extended result code definitions}
794**
795** In its default configuration, SQLite API routines return one of 30 integer
796** [result codes]. However, experience has shown that many of
797** these result codes are too coarse-grained. They do not provide as
798** much information about problems as programmers might like. In an effort to
799** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
800** and later) include
801** support for additional result codes that provide more detailed information
802** about errors. These [extended result codes] are enabled or disabled
803** on a per database connection basis using the
804** [sqlite3_extended_result_codes()] API. Or, the extended code for
805** the most recent error can be obtained using
806** [sqlite3_extended_errcode()].
807*/
808#define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8))
809#define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8))
810#define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8))
811#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
812#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
813#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
814#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
815#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
816#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
817#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
818#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
819#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
820#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
821#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
822#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
823#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
824#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
825#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
826#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
827#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
828#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
829#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
830#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
831#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
832#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
833#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
834#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
835#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
836#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
837#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8))
838#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8))
839#define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8))
840#define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8))
841#define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8))
842#define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8))
843#define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8))
844#define SQLITE_IOERR_IN_PAGE (SQLITE_IOERR | (34<<8))
845#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
846#define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8))
847#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
848#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
849#define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8))
850#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
851#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
852#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
853#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
854#define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
855#define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8))
856#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
857#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8))
858#define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8))
859#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
860#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
861#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
862#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
863#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8))
864#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8))
865#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
866#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
867#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
868#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
869#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
870#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
871#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
872#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
873#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
874#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
875#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
876#define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8))
877#define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8))
878#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
879#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
880#define SQLITE_NOTICE_RBU (SQLITE_NOTICE | (3<<8))
881#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
882#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8))
883#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8))
884#define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal use only */
885
886/*
887** CAPI3REF: Flags For File Open Operations
888**
889** These bit values are intended for use in the
890** 3rd parameter to the [sqlite3_open_v2()] interface and
891** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
892**
893** Only those flags marked as "Ok for sqlite3_open_v2()" may be
894** used as the third argument to the [sqlite3_open_v2()] interface.
895** The other flags have historically been ignored by sqlite3_open_v2(),
896** though future versions of SQLite might change so that an error is
897** raised if any of the disallowed bits are passed into sqlite3_open_v2().
898** Applications should not depend on the historical behavior.
899**
900** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into
901** [sqlite3_open_v2()] does *not* cause the underlying database file
902** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into
903** [sqlite3_open_v2()] has historically be a no-op and might become an
904** error in future versions of SQLite.
905*/
906#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
907#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
908#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
909#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
910#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
911#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
912#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
913#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
914#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
915#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
916#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
917#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
918#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
919#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
920#define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */
921#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
922#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
923#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
924#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
925#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
926#define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */
927#define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */
928
929/* Reserved: 0x00F00000 */
930/* Legacy compatibility: */
931#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
932
933
934/*
935** CAPI3REF: Device Characteristics
936**
937** The xDeviceCharacteristics method of the [sqlite3_io_methods]
938** object returns an integer which is a vector of these
939** bit values expressing I/O characteristics of the mass storage
940** device that holds the file that the [sqlite3_io_methods]
941** refers to.
942**
943** The SQLITE_IOCAP_ATOMIC property means that all writes of
944** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
945** mean that writes of blocks that are nnn bytes in size and
946** are aligned to an address which is an integer multiple of
947** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
948** that when data is appended to a file, the data is appended
949** first then the size of the file is extended, never the other
950** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
951** information is written to disk in the same order as calls
952** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
953** after reboot following a crash or power loss, the only bytes in a
954** file that were written at the application level might have changed
955** and that adjacent bytes, even bytes within the same sector are
956** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
957** flag indicates that a file cannot be deleted when open. The
958** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
959** read-only media and cannot be changed even by processes with
960** elevated privileges.
961**
962** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
963** filesystem supports doing multiple write operations atomically when those
964** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
965** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
966*/
967#define SQLITE_IOCAP_ATOMIC 0x00000001
968#define SQLITE_IOCAP_ATOMIC512 0x00000002
969#define SQLITE_IOCAP_ATOMIC1K 0x00000004
970#define SQLITE_IOCAP_ATOMIC2K 0x00000008
971#define SQLITE_IOCAP_ATOMIC4K 0x00000010
972#define SQLITE_IOCAP_ATOMIC8K 0x00000020
973#define SQLITE_IOCAP_ATOMIC16K 0x00000040
974#define SQLITE_IOCAP_ATOMIC32K 0x00000080
975#define SQLITE_IOCAP_ATOMIC64K 0x00000100
976#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
977#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
978#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
979#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
980#define SQLITE_IOCAP_IMMUTABLE 0x00002000
981#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000
982
983/*
984** CAPI3REF: File Locking Levels
985**
986** SQLite uses one of these integer values as the second
987** argument to calls it makes to the xLock() and xUnlock() methods
988** of an [sqlite3_io_methods] object. These values are ordered from
989** lest restrictive to most restrictive.
990**
991** The argument to xLock() is always SHARED or higher. The argument to
992** xUnlock is either SHARED or NONE.
993*/
994#define SQLITE_LOCK_NONE 0 /* xUnlock() only */
995#define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */
996#define SQLITE_LOCK_RESERVED 2 /* xLock() only */
997#define SQLITE_LOCK_PENDING 3 /* xLock() only */
998#define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */
999
1000/*
1001** CAPI3REF: Synchronization Type Flags
1002**
1003** When SQLite invokes the xSync() method of an
1004** [sqlite3_io_methods] object it uses a combination of
1005** these integer values as the second argument.
1006**
1007** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
1008** sync operation only needs to flush data to mass storage. Inode
1009** information need not be flushed. If the lower four bits of the flag
1010** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
1011** If the lower four bits equal SQLITE_SYNC_FULL, that means
1012** to use Mac OS X style fullsync instead of fsync().
1013**
1014** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
1015** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
1016** settings. The [synchronous pragma] determines when calls to the
1017** xSync VFS method occur and applies uniformly across all platforms.
1018** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
1019** energetic or rigorous or forceful the sync operations are and
1020** only make a difference on Mac OSX for the default SQLite code.
1021** (Third-party VFS implementations might also make the distinction
1022** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
1023** operating systems natively supported by SQLite, only Mac OSX
1024** cares about the difference.)
1025*/
1026#define SQLITE_SYNC_NORMAL 0x00002
1027#define SQLITE_SYNC_FULL 0x00003
1028#define SQLITE_SYNC_DATAONLY 0x00010
1029
1030/*
1031** CAPI3REF: OS Interface Open File Handle
1032**
1033** An [sqlite3_file] object represents an open file in the
1034** [sqlite3_vfs | OS interface layer]. Individual OS interface
1035** implementations will
1036** want to subclass this object by appending additional fields
1037** for their own use. The pMethods entry is a pointer to an
1038** [sqlite3_io_methods] object that defines methods for performing
1039** I/O operations on the open file.
1040*/
1041typedef struct sqlite3_file sqlite3_file;
1042struct sqlite3_file {
1043 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
1044};
1045
1046/*
1047** CAPI3REF: OS Interface File Virtual Methods Object
1048**
1049** Every file opened by the [sqlite3_vfs.xOpen] method populates an
1050** [sqlite3_file] object (or, more commonly, a subclass of the
1051** [sqlite3_file] object) with a pointer to an instance of this object.
1052** This object defines the methods used to perform various operations
1053** against the open file represented by the [sqlite3_file] object.
1054**
1055** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
1056** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
1057** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
1058** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
1059** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
1060** to NULL.
1061**
1062** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
1063** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
1064** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
1065** flag may be ORed in to indicate that only the data of the file
1066** and not its inode needs to be synced.
1067**
1068** The integer values to xLock() and xUnlock() are one of
1069** <ul>
1070** <li> [SQLITE_LOCK_NONE],
1071** <li> [SQLITE_LOCK_SHARED],
1072** <li> [SQLITE_LOCK_RESERVED],
1073** <li> [SQLITE_LOCK_PENDING], or
1074** <li> [SQLITE_LOCK_EXCLUSIVE].
1075** </ul>
1076** xLock() upgrades the database file lock. In other words, xLock() moves the
1077** database file lock in the direction NONE toward EXCLUSIVE. The argument to
1078** xLock() is always on of SHARED, RESERVED, PENDING, or EXCLUSIVE, never
1079** SQLITE_LOCK_NONE. If the database file lock is already at or above the
1080** requested lock, then the call to xLock() is a no-op.
1081** xUnlock() downgrades the database file lock to either SHARED or NONE.
1082* If the lock is already at or below the requested lock state, then the call
1083** to xUnlock() is a no-op.
1084** The xCheckReservedLock() method checks whether any database connection,
1085** either in this process or in some other process, is holding a RESERVED,
1086** PENDING, or EXCLUSIVE lock on the file. It returns true
1087** if such a lock exists and false otherwise.
1088**
1089** The xFileControl() method is a generic interface that allows custom
1090** VFS implementations to directly control an open file using the
1091** [sqlite3_file_control()] interface. The second "op" argument is an
1092** integer opcode. The third argument is a generic pointer intended to
1093** point to a structure that may contain arguments or space in which to
1094** write return values. Potential uses for xFileControl() might be
1095** functions to enable blocking locks with timeouts, to change the
1096** locking strategy (for example to use dot-file locks), to inquire
1097** about the status of a lock, or to break stale locks. The SQLite
1098** core reserves all opcodes less than 100 for its own use.
1099** A [file control opcodes | list of opcodes] less than 100 is available.
1100** Applications that define a custom xFileControl method should use opcodes
1101** greater than 100 to avoid conflicts. VFS implementations should
1102** return [SQLITE_NOTFOUND] for file control opcodes that they do not
1103** recognize.
1104**
1105** The xSectorSize() method returns the sector size of the
1106** device that underlies the file. The sector size is the
1107** minimum write that can be performed without disturbing
1108** other bytes in the file. The xDeviceCharacteristics()
1109** method returns a bit vector describing behaviors of the
1110** underlying device:
1111**
1112** <ul>
1113** <li> [SQLITE_IOCAP_ATOMIC]
1114** <li> [SQLITE_IOCAP_ATOMIC512]
1115** <li> [SQLITE_IOCAP_ATOMIC1K]
1116** <li> [SQLITE_IOCAP_ATOMIC2K]
1117** <li> [SQLITE_IOCAP_ATOMIC4K]
1118** <li> [SQLITE_IOCAP_ATOMIC8K]
1119** <li> [SQLITE_IOCAP_ATOMIC16K]
1120** <li> [SQLITE_IOCAP_ATOMIC32K]
1121** <li> [SQLITE_IOCAP_ATOMIC64K]
1122** <li> [SQLITE_IOCAP_SAFE_APPEND]
1123** <li> [SQLITE_IOCAP_SEQUENTIAL]
1124** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
1125** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
1126** <li> [SQLITE_IOCAP_IMMUTABLE]
1127** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
1128** </ul>
1129**
1130** The SQLITE_IOCAP_ATOMIC property means that all writes of
1131** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
1132** mean that writes of blocks that are nnn bytes in size and
1133** are aligned to an address which is an integer multiple of
1134** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
1135** that when data is appended to a file, the data is appended
1136** first then the size of the file is extended, never the other
1137** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
1138** information is written to disk in the same order as calls
1139** to xWrite().
1140**
1141** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
1142** in the unread portions of the buffer with zeros. A VFS that
1143** fails to zero-fill short reads might seem to work. However,
1144** failure to zero-fill short reads will eventually lead to
1145** database corruption.
1146*/
1147typedef struct sqlite3_io_methods sqlite3_io_methods;
1148struct sqlite3_io_methods {
1149 int iVersion;
1150 int (*xClose)(sqlite3_file*);
1151 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
1152 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
1153 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
1154 int (*xSync)(sqlite3_file*, int flags);
1155 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
1156 int (*xLock)(sqlite3_file*, int);
1157 int (*xUnlock)(sqlite3_file*, int);
1158 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
1159 int (*xFileControl)(sqlite3_file*, int op, void *pArg);
1160 int (*xSectorSize)(sqlite3_file*);
1161 int (*xDeviceCharacteristics)(sqlite3_file*);
1162 /* Methods above are valid for version 1 */
1163 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
1164 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
1165 void (*xShmBarrier)(sqlite3_file*);
1166 int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
1167 /* Methods above are valid for version 2 */
1168 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
1169 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
1170 /* Methods above are valid for version 3 */
1171 /* Additional methods may be added in future releases */
1172};
1173
1174/*
1175** CAPI3REF: Standard File Control Opcodes
1176** KEYWORDS: {file control opcodes} {file control opcode}
1177**
1178** These integer constants are opcodes for the xFileControl method
1179** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
1180** interface.
1181**
1182** <ul>
1183** <li>[[SQLITE_FCNTL_LOCKSTATE]]
1184** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
1185** opcode causes the xFileControl method to write the current state of
1186** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
1187** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
1188** into an integer that the pArg argument points to.
1189** This capability is only available if SQLite is compiled with [SQLITE_DEBUG].
1190**
1191** <li>[[SQLITE_FCNTL_SIZE_HINT]]
1192** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
1193** layer a hint of how large the database file will grow to be during the
1194** current transaction. This hint is not guaranteed to be accurate but it
1195** is often close. The underlying VFS might choose to preallocate database
1196** file space based on this hint in order to help writes to the database
1197** file run faster.
1198**
1199** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
1200** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
1201** implements [sqlite3_deserialize()] to set an upper bound on the size
1202** of the in-memory database. The argument is a pointer to a [sqlite3_int64].
1203** If the integer pointed to is negative, then it is filled in with the
1204** current limit. Otherwise the limit is set to the larger of the value
1205** of the integer pointed to and the current database size. The integer
1206** pointed to is set to the new limit.
1207**
1208** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
1209** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
1210** extends and truncates the database file in chunks of a size specified
1211** by the user. The fourth argument to [sqlite3_file_control()] should
1212** point to an integer (type int) containing the new chunk-size to use
1213** for the nominated database. Allocating database file space in large
1214** chunks (say 1MB at a time), may reduce file-system fragmentation and
1215** improve performance on some systems.
1216**
1217** <li>[[SQLITE_FCNTL_FILE_POINTER]]
1218** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
1219** to the [sqlite3_file] object associated with a particular database
1220** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER].
1221**
1222** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
1223** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
1224** to the [sqlite3_file] object associated with the journal file (either
1225** the [rollback journal] or the [write-ahead log]) for a particular database
1226** connection. See also [SQLITE_FCNTL_FILE_POINTER].
1227**
1228** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
1229** No longer in use.
1230**
1231** <li>[[SQLITE_FCNTL_SYNC]]
1232** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
1233** sent to the VFS immediately before the xSync method is invoked on a
1234** database file descriptor. Or, if the xSync method is not invoked
1235** because the user has configured SQLite with
1236** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
1237** of the xSync method. In most cases, the pointer argument passed with
1238** this file-control is NULL. However, if the database file is being synced
1239** as part of a multi-database commit, the argument points to a nul-terminated
1240** string containing the transactions super-journal file name. VFSes that
1241** do not need this signal should silently ignore this opcode. Applications
1242** should not call [sqlite3_file_control()] with this opcode as doing so may
1243** disrupt the operation of the specialized VFSes that do require it.
1244**
1245** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
1246** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
1247** and sent to the VFS after a transaction has been committed immediately
1248** but before the database is unlocked. VFSes that do not need this signal
1249** should silently ignore this opcode. Applications should not call
1250** [sqlite3_file_control()] with this opcode as doing so may disrupt the
1251** operation of the specialized VFSes that do require it.
1252**
1253** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
1254** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
1255** retry counts and intervals for certain disk I/O operations for the
1256** windows [VFS] in order to provide robustness in the presence of
1257** anti-virus programs. By default, the windows VFS will retry file read,
1258** file write, and file delete operations up to 10 times, with a delay
1259** of 25 milliseconds before the first retry and with the delay increasing
1260** by an additional 25 milliseconds with each subsequent retry. This
1261** opcode allows these two values (10 retries and 25 milliseconds of delay)
1262** to be adjusted. The values are changed for all database connections
1263** within the same process. The argument is a pointer to an array of two
1264** integers where the first integer is the new retry count and the second
1265** integer is the delay. If either integer is negative, then the setting
1266** is not changed but instead the prior value of that setting is written
1267** into the array entry, allowing the current retry settings to be
1268** interrogated. The zDbName parameter is ignored.
1269**
1270** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
1271** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
1272** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
1273** write ahead log ([WAL file]) and shared memory
1274** files used for transaction control
1275** are automatically deleted when the latest connection to the database
1276** closes. Setting persistent WAL mode causes those files to persist after
1277** close. Persisting the files is useful when other processes that do not
1278** have write permission on the directory containing the database file want
1279** to read the database file, as the WAL and shared memory files must exist
1280** in order for the database to be readable. The fourth parameter to
1281** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1282** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
1283** WAL mode. If the integer is -1, then it is overwritten with the current
1284** WAL persistence setting.
1285**
1286** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
1287** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
1288** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
1289** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
1290** xDeviceCharacteristics methods. The fourth parameter to
1291** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1292** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
1293** mode. If the integer is -1, then it is overwritten with the current
1294** zero-damage mode setting.
1295**
1296** <li>[[SQLITE_FCNTL_OVERWRITE]]
1297** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
1298** a write transaction to indicate that, unless it is rolled back for some
1299** reason, the entire database file will be overwritten by the current
1300** transaction. This is used by VACUUM operations.
1301**
1302** <li>[[SQLITE_FCNTL_VFSNAME]]
1303** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
1304** all [VFSes] in the VFS stack. The names are of all VFS shims and the
1305** final bottom-level VFS are written into memory obtained from
1306** [sqlite3_malloc()] and the result is stored in the char* variable
1307** that the fourth parameter of [sqlite3_file_control()] points to.
1308** The caller is responsible for freeing the memory when done. As with
1309** all file-control actions, there is no guarantee that this will actually
1310** do anything. Callers should initialize the char* variable to a NULL
1311** pointer in case this file-control is not implemented. This file-control
1312** is intended for diagnostic use only.
1313**
1314** <li>[[SQLITE_FCNTL_VFS_POINTER]]
1315** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
1316** [VFSes] currently in use. ^(The argument X in
1317** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
1318** of type "[sqlite3_vfs] **". This opcodes will set *X
1319** to a pointer to the top-level VFS.)^
1320** ^When there are multiple VFS shims in the stack, this opcode finds the
1321** upper-most shim only.
1322**
1323** <li>[[SQLITE_FCNTL_PRAGMA]]
1324** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1325** file control is sent to the open [sqlite3_file] object corresponding
1326** to the database file to which the pragma statement refers. ^The argument
1327** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1328** pointers to strings (char**) in which the second element of the array
1329** is the name of the pragma and the third element is the argument to the
1330** pragma or NULL if the pragma has no argument. ^The handler for an
1331** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1332** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1333** or the equivalent and that string will become the result of the pragma or
1334** the error message if the pragma fails. ^If the
1335** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1336** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
1337** file control returns [SQLITE_OK], then the parser assumes that the
1338** VFS has handled the PRAGMA itself and the parser generates a no-op
1339** prepared statement if result string is NULL, or that returns a copy
1340** of the result string if the string is non-NULL.
1341** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1342** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1343** that the VFS encountered an error while handling the [PRAGMA] and the
1344** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
1345** file control occurs at the beginning of pragma statement analysis and so
1346** it is able to override built-in [PRAGMA] statements.
1347**
1348** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1349** ^The [SQLITE_FCNTL_BUSYHANDLER]
1350** file-control may be invoked by SQLite on the database file handle
1351** shortly after it is opened in order to provide a custom VFS with access
1352** to the connection's busy-handler callback. The argument is of type (void**)
1353** - an array of two (void *) values. The first (void *) actually points
1354** to a function of type (int (*)(void *)). In order to invoke the connection's
1355** busy-handler, this function should be invoked with the second (void *) in
1356** the array as the only argument. If it returns non-zero, then the operation
1357** should be retried. If it returns zero, the custom VFS should abandon the
1358** current operation.
1359**
1360** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1361** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1362** to have SQLite generate a
1363** temporary filename using the same algorithm that is followed to generate
1364** temporary filenames for TEMP tables and other internal uses. The
1365** argument should be a char** which will be filled with the filename
1366** written into memory obtained from [sqlite3_malloc()]. The caller should
1367** invoke [sqlite3_free()] on the result to avoid a memory leak.
1368**
1369** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1370** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1371** maximum number of bytes that will be used for memory-mapped I/O.
1372** The argument is a pointer to a value of type sqlite3_int64 that
1373** is an advisory maximum number of bytes in the file to memory map. The
1374** pointer is overwritten with the old value. The limit is not changed if
1375** the value originally pointed to is negative, and so the current limit
1376** can be queried by passing in a pointer to a negative number. This
1377** file-control is used internally to implement [PRAGMA mmap_size].
1378**
1379** <li>[[SQLITE_FCNTL_TRACE]]
1380** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1381** to the VFS about what the higher layers of the SQLite stack are doing.
1382** This file control is used by some VFS activity tracing [shims].
1383** The argument is a zero-terminated string. Higher layers in the
1384** SQLite stack may generate instances of this file control if
1385** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1386**
1387** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1388** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1389** pointer to an integer and it writes a boolean into that integer depending
1390** on whether or not the file has been renamed, moved, or deleted since it
1391** was first opened.
1392**
1393** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1394** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1395** underlying native file handle associated with a file handle. This file
1396** control interprets its argument as a pointer to a native file handle and
1397** writes the resulting value there.
1398**
1399** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1400** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
1401** opcode causes the xFileControl method to swap the file handle with the one
1402** pointed to by the pArg argument. This capability is used during testing
1403** and only needs to be supported when SQLITE_TEST is defined.
1404**
1405** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1406** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1407** be advantageous to block on the next WAL lock if the lock is not immediately
1408** available. The WAL subsystem issues this signal during rare
1409** circumstances in order to fix a problem with priority inversion.
1410** Applications should <em>not</em> use this file-control.
1411**
1412** <li>[[SQLITE_FCNTL_ZIPVFS]]
1413** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1414** VFS should return SQLITE_NOTFOUND for this opcode.
1415**
1416** <li>[[SQLITE_FCNTL_RBU]]
1417** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1418** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for
1419** this opcode.
1420**
1421** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1422** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1423** the file descriptor is placed in "batch write mode", which
1424** means all subsequent write operations will be deferred and done
1425** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems
1426** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1427** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1428** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1429** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1430** no VFS interface calls on the same [sqlite3_file] file descriptor
1431** except for calls to the xWrite method and the xFileControl method
1432** with [SQLITE_FCNTL_SIZE_HINT].
1433**
1434** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1435** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1436** operations since the previous successful call to
1437** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1438** This file control returns [SQLITE_OK] if and only if the writes were
1439** all performed successfully and have been committed to persistent storage.
1440** ^Regardless of whether or not it is successful, this file control takes
1441** the file descriptor out of batch write mode so that all subsequent
1442** write operations are independent.
1443** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1444** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1445**
1446** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1447** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1448** operations since the previous successful call to
1449** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1450** ^This file control takes the file descriptor out of batch write mode
1451** so that all subsequent write operations are independent.
1452** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1453** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1454**
1455** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1456** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
1457** to block for up to M milliseconds before failing when attempting to
1458** obtain a file lock using the xLock or xShmLock methods of the VFS.
1459** The parameter is a pointer to a 32-bit signed integer that contains
1460** the value that M is to be set to. Before returning, the 32-bit signed
1461** integer is overwritten with the previous value of M.
1462**
1463** <li>[[SQLITE_FCNTL_DATA_VERSION]]
1464** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
1465** a database file. The argument is a pointer to a 32-bit unsigned integer.
1466** The "data version" for the pager is written into the pointer. The
1467** "data version" changes whenever any change occurs to the corresponding
1468** database file, either through SQL statements on the same database
1469** connection or through transactions committed by separate database
1470** connections possibly in other processes. The [sqlite3_total_changes()]
1471** interface can be used to find if any database on the connection has changed,
1472** but that interface responds to changes on TEMP as well as MAIN and does
1473** not provide a mechanism to detect changes to MAIN only. Also, the
1474** [sqlite3_total_changes()] interface responds to internal changes only and
1475** omits changes made by other database connections. The
1476** [PRAGMA data_version] command provides a mechanism to detect changes to
1477** a single attached database that occur due to other database connections,
1478** but omits changes implemented by the database connection on which it is
1479** called. This file control is the only mechanism to detect changes that
1480** happen either internally or externally and that are associated with
1481** a particular attached database.
1482**
1483** <li>[[SQLITE_FCNTL_CKPT_START]]
1484** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
1485** in wal mode before the client starts to copy pages from the wal
1486** file to the database file.
1487**
1488** <li>[[SQLITE_FCNTL_CKPT_DONE]]
1489** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
1490** in wal mode after the client has finished copying pages from the wal
1491** file to the database file, but before the *-shm file is updated to
1492** record the fact that the pages have been checkpointed.
1493**
1494** <li>[[SQLITE_FCNTL_EXTERNAL_READER]]
1495** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect
1496** whether or not there is a database client in another process with a wal-mode
1497** transaction open on the database or not. It is only available on unix.The
1498** (void*) argument passed with this file-control should be a pointer to a
1499** value of type (int). The integer value is set to 1 if the database is a wal
1500** mode database and there exists at least one client in another process that
1501** currently has an SQL transaction open on the database. It is set to 0 if
1502** the database is not a wal-mode db, or if there is no such connection in any
1503** other process. This opcode cannot be used to detect transactions opened
1504** by clients within the current process, only within other processes.
1505**
1506** <li>[[SQLITE_FCNTL_CKSM_FILE]]
1507** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the
1508** [checksum VFS shim] only.
1509**
1510** <li>[[SQLITE_FCNTL_RESET_CACHE]]
1511** If there is currently no transaction open on the database, and the
1512** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control
1513** purges the contents of the in-memory page cache. If there is an open
1514** transaction, or if the db is a temp-db, this opcode is a no-op, not an error.
1515** </ul>
1516*/
1517#define SQLITE_FCNTL_LOCKSTATE 1
1518#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2
1519#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3
1520#define SQLITE_FCNTL_LAST_ERRNO 4
1521#define SQLITE_FCNTL_SIZE_HINT 5
1522#define SQLITE_FCNTL_CHUNK_SIZE 6
1523#define SQLITE_FCNTL_FILE_POINTER 7
1524#define SQLITE_FCNTL_SYNC_OMITTED 8
1525#define SQLITE_FCNTL_WIN32_AV_RETRY 9
1526#define SQLITE_FCNTL_PERSIST_WAL 10
1527#define SQLITE_FCNTL_OVERWRITE 11
1528#define SQLITE_FCNTL_VFSNAME 12
1529#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
1530#define SQLITE_FCNTL_PRAGMA 14
1531#define SQLITE_FCNTL_BUSYHANDLER 15
1532#define SQLITE_FCNTL_TEMPFILENAME 16
1533#define SQLITE_FCNTL_MMAP_SIZE 18
1534#define SQLITE_FCNTL_TRACE 19
1535#define SQLITE_FCNTL_HAS_MOVED 20
1536#define SQLITE_FCNTL_SYNC 21
1537#define SQLITE_FCNTL_COMMIT_PHASETWO 22
1538#define SQLITE_FCNTL_WIN32_SET_HANDLE 23
1539#define SQLITE_FCNTL_WAL_BLOCK 24
1540#define SQLITE_FCNTL_ZIPVFS 25
1541#define SQLITE_FCNTL_RBU 26
1542#define SQLITE_FCNTL_VFS_POINTER 27
1543#define SQLITE_FCNTL_JOURNAL_POINTER 28
1544#define SQLITE_FCNTL_WIN32_GET_HANDLE 29
1545#define SQLITE_FCNTL_PDB 30
1546#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31
1547#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32
1548#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33
1549#define SQLITE_FCNTL_LOCK_TIMEOUT 34
1550#define SQLITE_FCNTL_DATA_VERSION 35
1551#define SQLITE_FCNTL_SIZE_LIMIT 36
1552#define SQLITE_FCNTL_CKPT_DONE 37
1553#define SQLITE_FCNTL_RESERVE_BYTES 38
1554#define SQLITE_FCNTL_CKPT_START 39
1555#define SQLITE_FCNTL_EXTERNAL_READER 40
1556#define SQLITE_FCNTL_CKSM_FILE 41
1557#define SQLITE_FCNTL_RESET_CACHE 42
1558
1559/* deprecated names */
1560#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE
1561#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE
1562#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO
1563
1564
1565/*
1566** CAPI3REF: Mutex Handle
1567**
1568** The mutex module within SQLite defines [sqlite3_mutex] to be an
1569** abstract type for a mutex object. The SQLite core never looks
1570** at the internal representation of an [sqlite3_mutex]. It only
1571** deals with pointers to the [sqlite3_mutex] object.
1572**
1573** Mutexes are created using [sqlite3_mutex_alloc()].
1574*/
1575typedef struct sqlite3_mutex sqlite3_mutex;
1576
1577/*
1578** CAPI3REF: Loadable Extension Thunk
1579**
1580** A pointer to the opaque sqlite3_api_routines structure is passed as
1581** the third parameter to entry points of [loadable extensions]. This
1582** structure must be typedefed in order to work around compiler warnings
1583** on some platforms.
1584*/
1585typedef struct sqlite3_api_routines sqlite3_api_routines;
1586
1587/*
1588** CAPI3REF: File Name
1589**
1590** Type [sqlite3_filename] is used by SQLite to pass filenames to the
1591** xOpen method of a [VFS]. It may be cast to (const char*) and treated
1592** as a normal, nul-terminated, UTF-8 buffer containing the filename, but
1593** may also be passed to special APIs such as:
1594**
1595** <ul>
1596** <li> sqlite3_filename_database()
1597** <li> sqlite3_filename_journal()
1598** <li> sqlite3_filename_wal()
1599** <li> sqlite3_uri_parameter()
1600** <li> sqlite3_uri_boolean()
1601** <li> sqlite3_uri_int64()
1602** <li> sqlite3_uri_key()
1603** </ul>
1604*/
1605typedef const char *sqlite3_filename;
1606
1607/*
1608** CAPI3REF: OS Interface Object
1609**
1610** An instance of the sqlite3_vfs object defines the interface between
1611** the SQLite core and the underlying operating system. The "vfs"
1612** in the name of the object stands for "virtual file system". See
1613** the [VFS | VFS documentation] for further information.
1614**
1615** The VFS interface is sometimes extended by adding new methods onto
1616** the end. Each time such an extension occurs, the iVersion field
1617** is incremented. The iVersion value started out as 1 in
1618** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1619** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1620** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields
1621** may be appended to the sqlite3_vfs object and the iVersion value
1622** may increase again in future versions of SQLite.
1623** Note that due to an oversight, the structure
1624** of the sqlite3_vfs object changed in the transition from
1625** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1626** and yet the iVersion field was not increased.
1627**
1628** The szOsFile field is the size of the subclassed [sqlite3_file]
1629** structure used by this VFS. mxPathname is the maximum length of
1630** a pathname in this VFS.
1631**
1632** Registered sqlite3_vfs objects are kept on a linked list formed by
1633** the pNext pointer. The [sqlite3_vfs_register()]
1634** and [sqlite3_vfs_unregister()] interfaces manage this list
1635** in a thread-safe way. The [sqlite3_vfs_find()] interface
1636** searches the list. Neither the application code nor the VFS
1637** implementation should use the pNext pointer.
1638**
1639** The pNext field is the only field in the sqlite3_vfs
1640** structure that SQLite will ever modify. SQLite will only access
1641** or modify this field while holding a particular static mutex.
1642** The application should never modify anything within the sqlite3_vfs
1643** object once the object has been registered.
1644**
1645** The zName field holds the name of the VFS module. The name must
1646** be unique across all VFS modules.
1647**
1648** [[sqlite3_vfs.xOpen]]
1649** ^SQLite guarantees that the zFilename parameter to xOpen
1650** is either a NULL pointer or string obtained
1651** from xFullPathname() with an optional suffix added.
1652** ^If a suffix is added to the zFilename parameter, it will
1653** consist of a single "-" character followed by no more than
1654** 11 alphanumeric and/or "-" characters.
1655** ^SQLite further guarantees that
1656** the string will be valid and unchanged until xClose() is
1657** called. Because of the previous sentence,
1658** the [sqlite3_file] can safely store a pointer to the
1659** filename if it needs to remember the filename for some reason.
1660** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1661** must invent its own temporary name for the file. ^Whenever the
1662** xFilename parameter is NULL it will also be the case that the
1663** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1664**
1665** The flags argument to xOpen() includes all bits set in
1666** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
1667** or [sqlite3_open16()] is used, then flags includes at least
1668** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1669** If xOpen() opens a file read-only then it sets *pOutFlags to
1670** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
1671**
1672** ^(SQLite will also add one of the following flags to the xOpen()
1673** call, depending on the object being opened:
1674**
1675** <ul>
1676** <li> [SQLITE_OPEN_MAIN_DB]
1677** <li> [SQLITE_OPEN_MAIN_JOURNAL]
1678** <li> [SQLITE_OPEN_TEMP_DB]
1679** <li> [SQLITE_OPEN_TEMP_JOURNAL]
1680** <li> [SQLITE_OPEN_TRANSIENT_DB]
1681** <li> [SQLITE_OPEN_SUBJOURNAL]
1682** <li> [SQLITE_OPEN_SUPER_JOURNAL]
1683** <li> [SQLITE_OPEN_WAL]
1684** </ul>)^
1685**
1686** The file I/O implementation can use the object type flags to
1687** change the way it deals with files. For example, an application
1688** that does not care about crash recovery or rollback might make
1689** the open of a journal file a no-op. Writes to this journal would
1690** also be no-ops, and any attempt to read the journal would return
1691** SQLITE_IOERR. Or the implementation might recognize that a database
1692** file will be doing page-aligned sector reads and writes in a random
1693** order and set up its I/O subsystem accordingly.
1694**
1695** SQLite might also add one of the following flags to the xOpen method:
1696**
1697** <ul>
1698** <li> [SQLITE_OPEN_DELETEONCLOSE]
1699** <li> [SQLITE_OPEN_EXCLUSIVE]
1700** </ul>
1701**
1702** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1703** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
1704** will be set for TEMP databases and their journals, transient
1705** databases, and subjournals.
1706**
1707** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1708** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1709** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1710** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1711** SQLITE_OPEN_CREATE, is used to indicate that file should always
1712** be created, and that it is an error if it already exists.
1713** It is <i>not</i> used to indicate the file should be opened
1714** for exclusive access.
1715**
1716** ^At least szOsFile bytes of memory are allocated by SQLite
1717** to hold the [sqlite3_file] structure passed as the third
1718** argument to xOpen. The xOpen method does not have to
1719** allocate the structure; it should just fill it in. Note that
1720** the xOpen method must set the sqlite3_file.pMethods to either
1721** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
1722** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
1723** element will be valid after xOpen returns regardless of the success
1724** or failure of the xOpen call.
1725**
1726** [[sqlite3_vfs.xAccess]]
1727** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1728** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1729** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1730** to test whether a file is at least readable. The SQLITE_ACCESS_READ
1731** flag is never actually used and is not implemented in the built-in
1732** VFSes of SQLite. The file is named by the second argument and can be a
1733** directory. The xAccess method returns [SQLITE_OK] on success or some
1734** non-zero error code if there is an I/O error or if the name of
1735** the file given in the second argument is illegal. If SQLITE_OK
1736** is returned, then non-zero or zero is written into *pResOut to indicate
1737** whether or not the file is accessible.
1738**
1739** ^SQLite will always allocate at least mxPathname+1 bytes for the
1740** output buffer xFullPathname. The exact size of the output buffer
1741** is also passed as a parameter to both methods. If the output buffer
1742** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1743** handled as a fatal error by SQLite, vfs implementations should endeavor
1744** to prevent this by setting mxPathname to a sufficiently large value.
1745**
1746** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1747** interfaces are not strictly a part of the filesystem, but they are
1748** included in the VFS structure for completeness.
1749** The xRandomness() function attempts to return nBytes bytes
1750** of good-quality randomness into zOut. The return value is
1751** the actual number of bytes of randomness obtained.
1752** The xSleep() method causes the calling thread to sleep for at
1753** least the number of microseconds given. ^The xCurrentTime()
1754** method returns a Julian Day Number for the current date and time as
1755** a floating point value.
1756** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1757** Day Number multiplied by 86400000 (the number of milliseconds in
1758** a 24-hour day).
1759** ^SQLite will use the xCurrentTimeInt64() method to get the current
1760** date and time if that method is available (if iVersion is 2 or
1761** greater and the function pointer is not NULL) and will fall back
1762** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1763**
1764** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1765** are not used by the SQLite core. These optional interfaces are provided
1766** by some VFSes to facilitate testing of the VFS code. By overriding
1767** system calls with functions under its control, a test program can
1768** simulate faults and error conditions that would otherwise be difficult
1769** or impossible to induce. The set of system calls that can be overridden
1770** varies from one VFS to another, and from one version of the same VFS to the
1771** next. Applications that use these interfaces must be prepared for any
1772** or all of these interfaces to be NULL or for their behavior to change
1773** from one release to the next. Applications must not attempt to access
1774** any of these methods if the iVersion of the VFS is less than 3.
1775*/
1776typedef struct sqlite3_vfs sqlite3_vfs;
1777typedef void (*sqlite3_syscall_ptr)(void);
1778struct sqlite3_vfs {
1779 int iVersion; /* Structure version number (currently 3) */
1780 int szOsFile; /* Size of subclassed sqlite3_file */
1781 int mxPathname; /* Maximum file pathname length */
1782 sqlite3_vfs *pNext; /* Next registered VFS */
1783 const char *zName; /* Name of this virtual file system */
1784 void *pAppData; /* Pointer to application-specific data */
1785 int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*,
1786 int flags, int *pOutFlags);
1787 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1788 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1789 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1790 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1791 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1792 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1793 void (*xDlClose)(sqlite3_vfs*, void*);
1794 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1795 int (*xSleep)(sqlite3_vfs*, int microseconds);
1796 int (*xCurrentTime)(sqlite3_vfs*, double*);
1797 int (*xGetLastError)(sqlite3_vfs*, int, char *);
1798 /*
1799 ** The methods above are in version 1 of the sqlite_vfs object
1800 ** definition. Those that follow are added in version 2 or later
1801 */
1802 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1803 /*
1804 ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1805 ** Those below are for version 3 and greater.
1806 */
1807 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1808 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1809 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1810 /*
1811 ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1812 ** New fields may be appended in future versions. The iVersion
1813 ** value will increment whenever this happens.
1814 */
1815};
1816
1817/*
1818** CAPI3REF: Flags for the xAccess VFS method
1819**
1820** These integer constants can be used as the third parameter to
1821** the xAccess method of an [sqlite3_vfs] object. They determine
1822** what kind of permissions the xAccess method is looking for.
1823** With SQLITE_ACCESS_EXISTS, the xAccess method
1824** simply checks whether the file exists.
1825** With SQLITE_ACCESS_READWRITE, the xAccess method
1826** checks whether the named directory is both readable and writable
1827** (in other words, if files can be added, removed, and renamed within
1828** the directory).
1829** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1830** [temp_store_directory pragma], though this could change in a future
1831** release of SQLite.
1832** With SQLITE_ACCESS_READ, the xAccess method
1833** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
1834** currently unused, though it might be used in a future release of
1835** SQLite.
1836*/
1837#define SQLITE_ACCESS_EXISTS 0
1838#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
1839#define SQLITE_ACCESS_READ 2 /* Unused */
1840
1841/*
1842** CAPI3REF: Flags for the xShmLock VFS method
1843**
1844** These integer constants define the various locking operations
1845** allowed by the xShmLock method of [sqlite3_io_methods]. The
1846** following are the only legal combinations of flags to the
1847** xShmLock method:
1848**
1849** <ul>
1850** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1851** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1852** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1853** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1854** </ul>
1855**
1856** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1857** was given on the corresponding lock.
1858**
1859** The xShmLock method can transition between unlocked and SHARED or
1860** between unlocked and EXCLUSIVE. It cannot transition between SHARED
1861** and EXCLUSIVE.
1862*/
1863#define SQLITE_SHM_UNLOCK 1
1864#define SQLITE_SHM_LOCK 2
1865#define SQLITE_SHM_SHARED 4
1866#define SQLITE_SHM_EXCLUSIVE 8
1867
1868/*
1869** CAPI3REF: Maximum xShmLock index
1870**
1871** The xShmLock method on [sqlite3_io_methods] may use values
1872** between 0 and this upper bound as its "offset" argument.
1873** The SQLite core will never attempt to acquire or release a
1874** lock outside of this range
1875*/
1876#define SQLITE_SHM_NLOCK 8
1877
1878
1879/*
1880** CAPI3REF: Initialize The SQLite Library
1881**
1882** ^The sqlite3_initialize() routine initializes the
1883** SQLite library. ^The sqlite3_shutdown() routine
1884** deallocates any resources that were allocated by sqlite3_initialize().
1885** These routines are designed to aid in process initialization and
1886** shutdown on embedded systems. Workstation applications using
1887** SQLite normally do not need to invoke either of these routines.
1888**
1889** A call to sqlite3_initialize() is an "effective" call if it is
1890** the first time sqlite3_initialize() is invoked during the lifetime of
1891** the process, or if it is the first time sqlite3_initialize() is invoked
1892** following a call to sqlite3_shutdown(). ^(Only an effective call
1893** of sqlite3_initialize() does any initialization. All other calls
1894** are harmless no-ops.)^
1895**
1896** A call to sqlite3_shutdown() is an "effective" call if it is the first
1897** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
1898** an effective call to sqlite3_shutdown() does any deinitialization.
1899** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1900**
1901** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1902** is not. The sqlite3_shutdown() interface must only be called from a
1903** single thread. All open [database connections] must be closed and all
1904** other SQLite resources must be deallocated prior to invoking
1905** sqlite3_shutdown().
1906**
1907** Among other things, ^sqlite3_initialize() will invoke
1908** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
1909** will invoke sqlite3_os_end().
1910**
1911** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1912** ^If for some reason, sqlite3_initialize() is unable to initialize
1913** the library (perhaps it is unable to allocate a needed resource such
1914** as a mutex) it returns an [error code] other than [SQLITE_OK].
1915**
1916** ^The sqlite3_initialize() routine is called internally by many other
1917** SQLite interfaces so that an application usually does not need to
1918** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
1919** calls sqlite3_initialize() so the SQLite library will be automatically
1920** initialized when [sqlite3_open()] is called if it has not be initialized
1921** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1922** compile-time option, then the automatic calls to sqlite3_initialize()
1923** are omitted and the application must call sqlite3_initialize() directly
1924** prior to using any other SQLite interface. For maximum portability,
1925** it is recommended that applications always invoke sqlite3_initialize()
1926** directly prior to using any other SQLite interface. Future releases
1927** of SQLite may require this. In other words, the behavior exhibited
1928** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1929** default behavior in some future release of SQLite.
1930**
1931** The sqlite3_os_init() routine does operating-system specific
1932** initialization of the SQLite library. The sqlite3_os_end()
1933** routine undoes the effect of sqlite3_os_init(). Typical tasks
1934** performed by these routines include allocation or deallocation
1935** of static resources, initialization of global variables,
1936** setting up a default [sqlite3_vfs] module, or setting up
1937** a default configuration using [sqlite3_config()].
1938**
1939** The application should never invoke either sqlite3_os_init()
1940** or sqlite3_os_end() directly. The application should only invoke
1941** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
1942** interface is called automatically by sqlite3_initialize() and
1943** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
1944** implementations for sqlite3_os_init() and sqlite3_os_end()
1945** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1946** When [custom builds | built for other platforms]
1947** (using the [SQLITE_OS_OTHER=1] compile-time
1948** option) the application must supply a suitable implementation for
1949** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1950** implementation of sqlite3_os_init() or sqlite3_os_end()
1951** must return [SQLITE_OK] on success and some other [error code] upon
1952** failure.
1953*/
1954SQLITE_API int sqlite3_initialize(void);
1955SQLITE_API int sqlite3_shutdown(void);
1956SQLITE_API int sqlite3_os_init(void);
1957SQLITE_API int sqlite3_os_end(void);
1958
1959/*
1960** CAPI3REF: Configuring The SQLite Library
1961**
1962** The sqlite3_config() interface is used to make global configuration
1963** changes to SQLite in order to tune SQLite to the specific needs of
1964** the application. The default configuration is recommended for most
1965** applications and so this routine is usually not necessary. It is
1966** provided to support rare applications with unusual needs.
1967**
1968** <b>The sqlite3_config() interface is not threadsafe. The application
1969** must ensure that no other SQLite interfaces are invoked by other
1970** threads while sqlite3_config() is running.</b>
1971**
1972** The first argument to sqlite3_config() is an integer
1973** [configuration option] that determines
1974** what property of SQLite is to be configured. Subsequent arguments
1975** vary depending on the [configuration option]
1976** in the first argument.
1977**
1978** For most configuration options, the sqlite3_config() interface
1979** may only be invoked prior to library initialization using
1980** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1981** The exceptional configuration options that may be invoked at any time
1982** are called "anytime configuration options".
1983** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1984** [sqlite3_shutdown()] with a first argument that is not an anytime
1985** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE.
1986** Note, however, that ^sqlite3_config() can be called as part of the
1987** implementation of an application-defined [sqlite3_os_init()].
1988**
1989** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1990** ^If the option is unknown or SQLite is unable to set the option
1991** then this routine returns a non-zero [error code].
1992*/
1993SQLITE_API int sqlite3_config(int, ...);
1994
1995/*
1996** CAPI3REF: Configure database connections
1997** METHOD: sqlite3
1998**
1999** The sqlite3_db_config() interface is used to make configuration
2000** changes to a [database connection]. The interface is similar to
2001** [sqlite3_config()] except that the changes apply to a single
2002** [database connection] (specified in the first argument).
2003**
2004** The second argument to sqlite3_db_config(D,V,...) is the
2005** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
2006** that indicates what aspect of the [database connection] is being configured.
2007** Subsequent arguments vary depending on the configuration verb.
2008**
2009** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
2010** the call is considered successful.
2011*/
2012SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
2013
2014/*
2015** CAPI3REF: Memory Allocation Routines
2016**
2017** An instance of this object defines the interface between SQLite
2018** and low-level memory allocation routines.
2019**
2020** This object is used in only one place in the SQLite interface.
2021** A pointer to an instance of this object is the argument to
2022** [sqlite3_config()] when the configuration option is
2023** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
2024** By creating an instance of this object
2025** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
2026** during configuration, an application can specify an alternative
2027** memory allocation subsystem for SQLite to use for all of its
2028** dynamic memory needs.
2029**
2030** Note that SQLite comes with several [built-in memory allocators]
2031** that are perfectly adequate for the overwhelming majority of applications
2032** and that this object is only useful to a tiny minority of applications
2033** with specialized memory allocation requirements. This object is
2034** also used during testing of SQLite in order to specify an alternative
2035** memory allocator that simulates memory out-of-memory conditions in
2036** order to verify that SQLite recovers gracefully from such
2037** conditions.
2038**
2039** The xMalloc, xRealloc, and xFree methods must work like the
2040** malloc(), realloc() and free() functions from the standard C library.
2041** ^SQLite guarantees that the second argument to
2042** xRealloc is always a value returned by a prior call to xRoundup.
2043**
2044** xSize should return the allocated size of a memory allocation
2045** previously obtained from xMalloc or xRealloc. The allocated size
2046** is always at least as big as the requested size but may be larger.
2047**
2048** The xRoundup method returns what would be the allocated size of
2049** a memory allocation given a particular requested size. Most memory
2050** allocators round up memory allocations at least to the next multiple
2051** of 8. Some allocators round up to a larger multiple or to a power of 2.
2052** Every memory allocation request coming in through [sqlite3_malloc()]
2053** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
2054** that causes the corresponding memory allocation to fail.
2055**
2056** The xInit method initializes the memory allocator. For example,
2057** it might allocate any required mutexes or initialize internal data
2058** structures. The xShutdown method is invoked (indirectly) by
2059** [sqlite3_shutdown()] and should deallocate any resources acquired
2060** by xInit. The pAppData pointer is used as the only parameter to
2061** xInit and xShutdown.
2062**
2063** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
2064** the xInit method, so the xInit method need not be threadsafe. The
2065** xShutdown method is only called from [sqlite3_shutdown()] so it does
2066** not need to be threadsafe either. For all other methods, SQLite
2067** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
2068** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
2069** it is by default) and so the methods are automatically serialized.
2070** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
2071** methods must be threadsafe or else make their own arrangements for
2072** serialization.
2073**
2074** SQLite will never invoke xInit() more than once without an intervening
2075** call to xShutdown().
2076*/
2077typedef struct sqlite3_mem_methods sqlite3_mem_methods;
2078struct sqlite3_mem_methods {
2079 void *(*xMalloc)(int); /* Memory allocation function */
2080 void (*xFree)(void*); /* Free a prior allocation */
2081 void *(*xRealloc)(void*,int); /* Resize an allocation */
2082 int (*xSize)(void*); /* Return the size of an allocation */
2083 int (*xRoundup)(int); /* Round up request size to allocation size */
2084 int (*xInit)(void*); /* Initialize the memory allocator */
2085 void (*xShutdown)(void*); /* Deinitialize the memory allocator */
2086 void *pAppData; /* Argument to xInit() and xShutdown() */
2087};
2088
2089/*
2090** CAPI3REF: Configuration Options
2091** KEYWORDS: {configuration option}
2092**
2093** These constants are the available integer configuration options that
2094** can be passed as the first argument to the [sqlite3_config()] interface.
2095**
2096** Most of the configuration options for sqlite3_config()
2097** will only work if invoked prior to [sqlite3_initialize()] or after
2098** [sqlite3_shutdown()]. The few exceptions to this rule are called
2099** "anytime configuration options".
2100** ^Calling [sqlite3_config()] with a first argument that is not an
2101** anytime configuration option in between calls to [sqlite3_initialize()] and
2102** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE.
2103**
2104** The set of anytime configuration options can change (by insertions
2105** and/or deletions) from one release of SQLite to the next.
2106** As of SQLite version 3.42.0, the complete set of anytime configuration
2107** options is:
2108** <ul>
2109** <li> SQLITE_CONFIG_LOG
2110** <li> SQLITE_CONFIG_PCACHE_HDRSZ
2111** </ul>
2112**
2113** New configuration options may be added in future releases of SQLite.
2114** Existing configuration options might be discontinued. Applications
2115** should check the return code from [sqlite3_config()] to make sure that
2116** the call worked. The [sqlite3_config()] interface will return a
2117** non-zero [error code] if a discontinued or unsupported configuration option
2118** is invoked.
2119**
2120** <dl>
2121** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
2122** <dd>There are no arguments to this option. ^This option sets the
2123** [threading mode] to Single-thread. In other words, it disables
2124** all mutexing and puts SQLite into a mode where it can only be used
2125** by a single thread. ^If SQLite is compiled with
2126** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
2127** it is not possible to change the [threading mode] from its default
2128** value of Single-thread and so [sqlite3_config()] will return
2129** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
2130** configuration option.</dd>
2131**
2132** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
2133** <dd>There are no arguments to this option. ^This option sets the
2134** [threading mode] to Multi-thread. In other words, it disables
2135** mutexing on [database connection] and [prepared statement] objects.
2136** The application is responsible for serializing access to
2137** [database connections] and [prepared statements]. But other mutexes
2138** are enabled so that SQLite will be safe to use in a multi-threaded
2139** environment as long as no two threads attempt to use the same
2140** [database connection] at the same time. ^If SQLite is compiled with
2141** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
2142** it is not possible to set the Multi-thread [threading mode] and
2143** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
2144** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
2145**
2146** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
2147** <dd>There are no arguments to this option. ^This option sets the
2148** [threading mode] to Serialized. In other words, this option enables
2149** all mutexes including the recursive
2150** mutexes on [database connection] and [prepared statement] objects.
2151** In this mode (which is the default when SQLite is compiled with
2152** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
2153** to [database connections] and [prepared statements] so that the
2154** application is free to use the same [database connection] or the
2155** same [prepared statement] in different threads at the same time.
2156** ^If SQLite is compiled with
2157** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
2158** it is not possible to set the Serialized [threading mode] and
2159** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
2160** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
2161**
2162** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
2163** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
2164** a pointer to an instance of the [sqlite3_mem_methods] structure.
2165** The argument specifies
2166** alternative low-level memory allocation routines to be used in place of
2167** the memory allocation routines built into SQLite.)^ ^SQLite makes
2168** its own private copy of the content of the [sqlite3_mem_methods] structure
2169** before the [sqlite3_config()] call returns.</dd>
2170**
2171** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
2172** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
2173** is a pointer to an instance of the [sqlite3_mem_methods] structure.
2174** The [sqlite3_mem_methods]
2175** structure is filled with the currently defined memory allocation routines.)^
2176** This option can be used to overload the default memory allocation
2177** routines with a wrapper that simulations memory allocation failure or
2178** tracks memory usage, for example. </dd>
2179**
2180** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
2181** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
2182** type int, interpreted as a boolean, which if true provides a hint to
2183** SQLite that it should avoid large memory allocations if possible.
2184** SQLite will run faster if it is free to make large memory allocations,
2185** but some application might prefer to run slower in exchange for
2186** guarantees about memory fragmentation that are possible if large
2187** allocations are avoided. This hint is normally off.
2188** </dd>
2189**
2190** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
2191** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
2192** interpreted as a boolean, which enables or disables the collection of
2193** memory allocation statistics. ^(When memory allocation statistics are
2194** disabled, the following SQLite interfaces become non-operational:
2195** <ul>
2196** <li> [sqlite3_hard_heap_limit64()]
2197** <li> [sqlite3_memory_used()]
2198** <li> [sqlite3_memory_highwater()]
2199** <li> [sqlite3_soft_heap_limit64()]
2200** <li> [sqlite3_status64()]
2201** </ul>)^
2202** ^Memory allocation statistics are enabled by default unless SQLite is
2203** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
2204** allocation statistics are disabled by default.
2205** </dd>
2206**
2207** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
2208** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
2209** </dd>
2210**
2211** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
2212** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
2213** that SQLite can use for the database page cache with the default page
2214** cache implementation.
2215** This configuration option is a no-op if an application-defined page
2216** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
2217** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
2218** 8-byte aligned memory (pMem), the size of each page cache line (sz),
2219** and the number of cache lines (N).
2220** The sz argument should be the size of the largest database page
2221** (a power of two between 512 and 65536) plus some extra bytes for each
2222** page header. ^The number of extra bytes needed by the page header
2223** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
2224** ^It is harmless, apart from the wasted memory,
2225** for the sz parameter to be larger than necessary. The pMem
2226** argument must be either a NULL pointer or a pointer to an 8-byte
2227** aligned block of memory of at least sz*N bytes, otherwise
2228** subsequent behavior is undefined.
2229** ^When pMem is not NULL, SQLite will strive to use the memory provided
2230** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
2231** a page cache line is larger than sz bytes or if all of the pMem buffer
2232** is exhausted.
2233** ^If pMem is NULL and N is non-zero, then each database connection
2234** does an initial bulk allocation for page cache memory
2235** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
2236** of -1024*N bytes if N is negative, . ^If additional
2237** page cache memory is needed beyond what is provided by the initial
2238** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
2239** additional cache line. </dd>
2240**
2241** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
2242** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
2243** that SQLite will use for all of its dynamic memory allocation needs
2244** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
2245** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
2246** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
2247** [SQLITE_ERROR] if invoked otherwise.
2248** ^There are three arguments to SQLITE_CONFIG_HEAP:
2249** An 8-byte aligned pointer to the memory,
2250** the number of bytes in the memory buffer, and the minimum allocation size.
2251** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
2252** to using its default memory allocator (the system malloc() implementation),
2253** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
2254** memory pointer is not NULL then the alternative memory
2255** allocator is engaged to handle all of SQLites memory allocation needs.
2256** The first pointer (the memory pointer) must be aligned to an 8-byte
2257** boundary or subsequent behavior of SQLite will be undefined.
2258** The minimum allocation size is capped at 2**12. Reasonable values
2259** for the minimum allocation size are 2**5 through 2**8.</dd>
2260**
2261** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
2262** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
2263** pointer to an instance of the [sqlite3_mutex_methods] structure.
2264** The argument specifies alternative low-level mutex routines to be used
2265** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of
2266** the content of the [sqlite3_mutex_methods] structure before the call to
2267** [sqlite3_config()] returns. ^If SQLite is compiled with
2268** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
2269** the entire mutexing subsystem is omitted from the build and hence calls to
2270** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
2271** return [SQLITE_ERROR].</dd>
2272**
2273** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
2274** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
2275** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The
2276** [sqlite3_mutex_methods]
2277** structure is filled with the currently defined mutex routines.)^
2278** This option can be used to overload the default mutex allocation
2279** routines with a wrapper used to track mutex usage for performance
2280** profiling or testing, for example. ^If SQLite is compiled with
2281** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
2282** the entire mutexing subsystem is omitted from the build and hence calls to
2283** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
2284** return [SQLITE_ERROR].</dd>
2285**
2286** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
2287** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
2288** the default size of lookaside memory on each [database connection].
2289** The first argument is the
2290** size of each lookaside buffer slot and the second is the number of
2291** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE
2292** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
2293** option to [sqlite3_db_config()] can be used to change the lookaside
2294** configuration on individual connections.)^ </dd>
2295**
2296** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
2297** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
2298** a pointer to an [sqlite3_pcache_methods2] object. This object specifies
2299** the interface to a custom page cache implementation.)^
2300** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
2301**
2302** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
2303** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
2304** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of
2305** the current page cache implementation into that object.)^ </dd>
2306**
2307** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
2308** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
2309** global [error log].
2310** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
2311** function with a call signature of void(*)(void*,int,const char*),
2312** and a pointer to void. ^If the function pointer is not NULL, it is
2313** invoked by [sqlite3_log()] to process each logging event. ^If the
2314** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
2315** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
2316** passed through as the first parameter to the application-defined logger
2317** function whenever that function is invoked. ^The second parameter to
2318** the logger function is a copy of the first parameter to the corresponding
2319** [sqlite3_log()] call and is intended to be a [result code] or an
2320** [extended result code]. ^The third parameter passed to the logger is
2321** log message after formatting via [sqlite3_snprintf()].
2322** The SQLite logging interface is not reentrant; the logger function
2323** supplied by the application must not invoke any SQLite interface.
2324** In a multi-threaded application, the application-defined logger
2325** function must be threadsafe. </dd>
2326**
2327** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
2328** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
2329** If non-zero, then URI handling is globally enabled. If the parameter is zero,
2330** then URI handling is globally disabled.)^ ^If URI handling is globally
2331** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
2332** [sqlite3_open16()] or
2333** specified as part of [ATTACH] commands are interpreted as URIs, regardless
2334** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
2335** connection is opened. ^If it is globally disabled, filenames are
2336** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
2337** database connection is opened. ^(By default, URI handling is globally
2338** disabled. The default value may be changed by compiling with the
2339** [SQLITE_USE_URI] symbol defined.)^
2340**
2341** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
2342** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
2343** argument which is interpreted as a boolean in order to enable or disable
2344** the use of covering indices for full table scans in the query optimizer.
2345** ^The default setting is determined
2346** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
2347** if that compile-time option is omitted.
2348** The ability to disable the use of covering indices for full table scans
2349** is because some incorrectly coded legacy applications might malfunction
2350** when the optimization is enabled. Providing the ability to
2351** disable the optimization allows the older, buggy application code to work
2352** without change even with newer versions of SQLite.
2353**
2354** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
2355** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
2356** <dd> These options are obsolete and should not be used by new code.
2357** They are retained for backwards compatibility but are now no-ops.
2358** </dd>
2359**
2360** [[SQLITE_CONFIG_SQLLOG]]
2361** <dt>SQLITE_CONFIG_SQLLOG
2362** <dd>This option is only available if sqlite is compiled with the
2363** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
2364** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
2365** The second should be of type (void*). The callback is invoked by the library
2366** in three separate circumstances, identified by the value passed as the
2367** fourth parameter. If the fourth parameter is 0, then the database connection
2368** passed as the second argument has just been opened. The third argument
2369** points to a buffer containing the name of the main database file. If the
2370** fourth parameter is 1, then the SQL statement that the third parameter
2371** points to has just been executed. Or, if the fourth parameter is 2, then
2372** the connection being passed as the second parameter is being closed. The
2373** third parameter is passed NULL In this case. An example of using this
2374** configuration option can be seen in the "test_sqllog.c" source file in
2375** the canonical SQLite source tree.</dd>
2376**
2377** [[SQLITE_CONFIG_MMAP_SIZE]]
2378** <dt>SQLITE_CONFIG_MMAP_SIZE
2379** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
2380** that are the default mmap size limit (the default setting for
2381** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
2382** ^The default setting can be overridden by each database connection using
2383** either the [PRAGMA mmap_size] command, or by using the
2384** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
2385** will be silently truncated if necessary so that it does not exceed the
2386** compile-time maximum mmap size set by the
2387** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
2388** ^If either argument to this option is negative, then that argument is
2389** changed to its compile-time default.
2390**
2391** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
2392** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
2393** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
2394** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
2395** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
2396** that specifies the maximum size of the created heap.
2397**
2398** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
2399** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
2400** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
2401** is a pointer to an integer and writes into that integer the number of extra
2402** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
2403** The amount of extra space required can change depending on the compiler,
2404** target platform, and SQLite version.
2405**
2406** [[SQLITE_CONFIG_PMASZ]]
2407** <dt>SQLITE_CONFIG_PMASZ
2408** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
2409** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
2410** sorter to that integer. The default minimum PMA Size is set by the
2411** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched
2412** to help with sort operations when multithreaded sorting
2413** is enabled (using the [PRAGMA threads] command) and the amount of content
2414** to be sorted exceeds the page size times the minimum of the
2415** [PRAGMA cache_size] setting and this value.
2416**
2417** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
2418** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
2419** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
2420** becomes the [statement journal] spill-to-disk threshold.
2421** [Statement journals] are held in memory until their size (in bytes)
2422** exceeds this threshold, at which point they are written to disk.
2423** Or if the threshold is -1, statement journals are always held
2424** exclusively in memory.
2425** Since many statement journals never become large, setting the spill
2426** threshold to a value such as 64KiB can greatly reduce the amount of
2427** I/O required to support statement rollback.
2428** The default value for this setting is controlled by the
2429** [SQLITE_STMTJRNL_SPILL] compile-time option.
2430**
2431** [[SQLITE_CONFIG_SORTERREF_SIZE]]
2432** <dt>SQLITE_CONFIG_SORTERREF_SIZE
2433** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
2434** of type (int) - the new value of the sorter-reference size threshold.
2435** Usually, when SQLite uses an external sort to order records according
2436** to an ORDER BY clause, all fields required by the caller are present in the
2437** sorted records. However, if SQLite determines based on the declared type
2438** of a table column that its values are likely to be very large - larger
2439** than the configured sorter-reference size threshold - then a reference
2440** is stored in each sorted record and the required column values loaded
2441** from the database as records are returned in sorted order. The default
2442** value for this option is to never use this optimization. Specifying a
2443** negative value for this option restores the default behaviour.
2444** This option is only available if SQLite is compiled with the
2445** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
2446**
2447** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
2448** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
2449** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
2450** [sqlite3_int64] parameter which is the default maximum size for an in-memory
2451** database created using [sqlite3_deserialize()]. This default maximum
2452** size can be adjusted up or down for individual databases using the
2453** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this
2454** configuration setting is never used, then the default maximum is determined
2455** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that
2456** compile-time option is not set, then the default maximum is 1073741824.
2457** </dl>
2458*/
2459#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
2460#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
2461#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
2462#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
2463#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
2464#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */
2465#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
2466#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
2467#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
2468#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
2469#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
2470/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
2471#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
2472#define SQLITE_CONFIG_PCACHE 14 /* no-op */
2473#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
2474#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
2475#define SQLITE_CONFIG_URI 17 /* int */
2476#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
2477#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
2478#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
2479#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
2480#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
2481#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
2482#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */
2483#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */
2484#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */
2485#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */
2486#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */
2487#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */
2488
2489/*
2490** CAPI3REF: Database Connection Configuration Options
2491**
2492** These constants are the available integer configuration options that
2493** can be passed as the second argument to the [sqlite3_db_config()] interface.
2494**
2495** New configuration options may be added in future releases of SQLite.
2496** Existing configuration options might be discontinued. Applications
2497** should check the return code from [sqlite3_db_config()] to make sure that
2498** the call worked. ^The [sqlite3_db_config()] interface will return a
2499** non-zero [error code] if a discontinued or unsupported configuration option
2500** is invoked.
2501**
2502** <dl>
2503** [[SQLITE_DBCONFIG_LOOKASIDE]]
2504** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
2505** <dd> ^This option takes three additional arguments that determine the
2506** [lookaside memory allocator] configuration for the [database connection].
2507** ^The first argument (the third parameter to [sqlite3_db_config()] is a
2508** pointer to a memory buffer to use for lookaside memory.
2509** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
2510** may be NULL in which case SQLite will allocate the
2511** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
2512** size of each lookaside buffer slot. ^The third argument is the number of
2513** slots. The size of the buffer in the first argument must be greater than
2514** or equal to the product of the second and third arguments. The buffer
2515** must be aligned to an 8-byte boundary. ^If the second argument to
2516** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
2517** rounded down to the next smaller multiple of 8. ^(The lookaside memory
2518** configuration for a database connection can only be changed when that
2519** connection is not currently using lookaside memory, or in other words
2520** when the "current value" returned by
2521** [sqlite3_db_status](D,[SQLITE_DBSTATUS_LOOKASIDE_USED],...) is zero.
2522** Any attempt to change the lookaside memory configuration when lookaside
2523** memory is in use leaves the configuration unchanged and returns
2524** [SQLITE_BUSY].)^</dd>
2525**
2526** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
2527** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2528** <dd> ^This option is used to enable or disable the enforcement of
2529** [foreign key constraints]. There should be two additional arguments.
2530** The first argument is an integer which is 0 to disable FK enforcement,
2531** positive to enable FK enforcement or negative to leave FK enforcement
2532** unchanged. The second parameter is a pointer to an integer into which
2533** is written 0 or 1 to indicate whether FK enforcement is off or on
2534** following this call. The second parameter may be a NULL pointer, in
2535** which case the FK enforcement setting is not reported back. </dd>
2536**
2537** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
2538** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2539** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2540** There should be two additional arguments.
2541** The first argument is an integer which is 0 to disable triggers,
2542** positive to enable triggers or negative to leave the setting unchanged.
2543** The second parameter is a pointer to an integer into which
2544** is written 0 or 1 to indicate whether triggers are disabled or enabled
2545** following this call. The second parameter may be a NULL pointer, in
2546** which case the trigger setting is not reported back.
2547**
2548** <p>Originally this option disabled all triggers. ^(However, since
2549** SQLite version 3.35.0, TEMP triggers are still allowed even if
2550** this option is off. So, in other words, this option now only disables
2551** triggers in the main database schema or in the schemas of ATTACH-ed
2552** databases.)^ </dd>
2553**
2554** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
2555** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
2556** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
2557** There should be two additional arguments.
2558** The first argument is an integer which is 0 to disable views,
2559** positive to enable views or negative to leave the setting unchanged.
2560** The second parameter is a pointer to an integer into which
2561** is written 0 or 1 to indicate whether views are disabled or enabled
2562** following this call. The second parameter may be a NULL pointer, in
2563** which case the view setting is not reported back.
2564**
2565** <p>Originally this option disabled all views. ^(However, since
2566** SQLite version 3.35.0, TEMP views are still allowed even if
2567** this option is off. So, in other words, this option now only disables
2568** views in the main database schema or in the schemas of ATTACH-ed
2569** databases.)^ </dd>
2570**
2571** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
2572** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
2573** <dd> ^This option is used to enable or disable the
2574** [fts3_tokenizer()] function which is part of the
2575** [FTS3] full-text search engine extension.
2576** There should be two additional arguments.
2577** The first argument is an integer which is 0 to disable fts3_tokenizer() or
2578** positive to enable fts3_tokenizer() or negative to leave the setting
2579** unchanged.
2580** The second parameter is a pointer to an integer into which
2581** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2582** following this call. The second parameter may be a NULL pointer, in
2583** which case the new setting is not reported back. </dd>
2584**
2585** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
2586** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2587** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2588** interface independently of the [load_extension()] SQL function.
2589** The [sqlite3_enable_load_extension()] API enables or disables both the
2590** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2591** There should be two additional arguments.
2592** When the first argument to this interface is 1, then only the C-API is
2593** enabled and the SQL function remains disabled. If the first argument to
2594** this interface is 0, then both the C-API and the SQL function are disabled.
2595** If the first argument is -1, then no changes are made to state of either the
2596** C-API or the SQL function.
2597** The second parameter is a pointer to an integer into which
2598** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2599** is disabled or enabled following this call. The second parameter may
2600** be a NULL pointer, in which case the new setting is not reported back.
2601** </dd>
2602**
2603** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2604** <dd> ^This option is used to change the name of the "main" database
2605** schema. ^The sole argument is a pointer to a constant UTF8 string
2606** which will become the new schema name in place of "main". ^SQLite
2607** does not make a copy of the new main schema name string, so the application
2608** must ensure that the argument passed into this DBCONFIG option is unchanged
2609** until after the database connection closes.
2610** </dd>
2611**
2612** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
2613** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2614** <dd> Usually, when a database in wal mode is closed or detached from a
2615** database handle, SQLite checks if this will mean that there are now no
2616** connections at all to the database. If so, it performs a checkpoint
2617** operation before closing the connection. This option may be used to
2618** override this behaviour. The first parameter passed to this operation
2619** is an integer - positive to disable checkpoints-on-close, or zero (the
2620** default) to enable them, and negative to leave the setting unchanged.
2621** The second parameter is a pointer to an integer
2622** into which is written 0 or 1 to indicate whether checkpoints-on-close
2623** have been disabled - 0 if they are not disabled, 1 if they are.
2624** </dd>
2625**
2626** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2627** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2628** the [query planner stability guarantee] (QPSG). When the QPSG is active,
2629** a single SQL query statement will always use the same algorithm regardless
2630** of values of [bound parameters].)^ The QPSG disables some query optimizations
2631** that look at the values of bound parameters, which can make some queries
2632** slower. But the QPSG has the advantage of more predictable behavior. With
2633** the QPSG active, SQLite will always use the same query plan in the field as
2634** was used during testing in the lab.
2635** The first argument to this setting is an integer which is 0 to disable
2636** the QPSG, positive to enable QPSG, or negative to leave the setting
2637** unchanged. The second parameter is a pointer to an integer into which
2638** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2639** following this call.
2640** </dd>
2641**
2642** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
2643** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
2644** include output for any operations performed by trigger programs. This
2645** option is used to set or clear (the default) a flag that governs this
2646** behavior. The first parameter passed to this operation is an integer -
2647** positive to enable output for trigger programs, or zero to disable it,
2648** or negative to leave the setting unchanged.
2649** The second parameter is a pointer to an integer into which is written
2650** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
2651** it is not disabled, 1 if it is.
2652** </dd>
2653**
2654** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
2655** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
2656** [VACUUM] in order to reset a database back to an empty database
2657** with no schema and no content. The following process works even for
2658** a badly corrupted database file:
2659** <ol>
2660** <li> If the database connection is newly opened, make sure it has read the
2661** database schema by preparing then discarding some query against the
2662** database, or calling sqlite3_table_column_metadata(), ignoring any
2663** errors. This step is only necessary if the application desires to keep
2664** the database in WAL mode after the reset if it was in WAL mode before
2665** the reset.
2666** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
2667** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
2668** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
2669** </ol>
2670** Because resetting a database is destructive and irreversible, the
2671** process requires the use of this obscure API and multiple steps to
2672** help ensure that it does not happen by accident. Because this
2673** feature must be capable of resetting corrupt databases, and
2674** shutting down virtual tables may require access to that corrupt
2675** storage, the library must abandon any installed virtual tables
2676** without calling their xDestroy() methods.
2677**
2678** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
2679** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
2680** "defensive" flag for a database connection. When the defensive
2681** flag is enabled, language features that allow ordinary SQL to
2682** deliberately corrupt the database file are disabled. The disabled
2683** features include but are not limited to the following:
2684** <ul>
2685** <li> The [PRAGMA writable_schema=ON] statement.
2686** <li> The [PRAGMA journal_mode=OFF] statement.
2687** <li> The [PRAGMA schema_version=N] statement.
2688** <li> Writes to the [sqlite_dbpage] virtual table.
2689** <li> Direct writes to [shadow tables].
2690** </ul>
2691** </dd>
2692**
2693** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
2694** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
2695** "writable_schema" flag. This has the same effect and is logically equivalent
2696** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
2697** The first argument to this setting is an integer which is 0 to disable
2698** the writable_schema, positive to enable writable_schema, or negative to
2699** leave the setting unchanged. The second parameter is a pointer to an
2700** integer into which is written 0 or 1 to indicate whether the writable_schema
2701** is enabled or disabled following this call.
2702** </dd>
2703**
2704** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
2705** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
2706** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
2707** the legacy behavior of the [ALTER TABLE RENAME] command such it
2708** behaves as it did prior to [version 3.24.0] (2018-06-04). See the
2709** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
2710** additional information. This feature can also be turned on and off
2711** using the [PRAGMA legacy_alter_table] statement.
2712** </dd>
2713**
2714** [[SQLITE_DBCONFIG_DQS_DML]]
2715** <dt>SQLITE_DBCONFIG_DQS_DML</dt>
2716** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
2717** the legacy [double-quoted string literal] misfeature for DML statements
2718** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
2719** default value of this setting is determined by the [-DSQLITE_DQS]
2720** compile-time option.
2721** </dd>
2722**
2723** [[SQLITE_DBCONFIG_DQS_DDL]]
2724** <dt>SQLITE_DBCONFIG_DQS_DDL</dt>
2725** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
2726** the legacy [double-quoted string literal] misfeature for DDL statements,
2727** such as CREATE TABLE and CREATE INDEX. The
2728** default value of this setting is determined by the [-DSQLITE_DQS]
2729** compile-time option.
2730** </dd>
2731**
2732** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
2733** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt>
2734** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
2735** assume that database schemas are untainted by malicious content.
2736** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
2737** takes additional defensive steps to protect the application from harm
2738** including:
2739** <ul>
2740** <li> Prohibit the use of SQL functions inside triggers, views,
2741** CHECK constraints, DEFAULT clauses, expression indexes,
2742** partial indexes, or generated columns
2743** unless those functions are tagged with [SQLITE_INNOCUOUS].
2744** <li> Prohibit the use of virtual tables inside of triggers or views
2745** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
2746** </ul>
2747** This setting defaults to "on" for legacy compatibility, however
2748** all applications are advised to turn it off if possible. This setting
2749** can also be controlled using the [PRAGMA trusted_schema] statement.
2750** </dd>
2751**
2752** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
2753** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt>
2754** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
2755** the legacy file format flag. When activated, this flag causes all newly
2756** created database file to have a schema format version number (the 4-byte
2757** integer found at offset 44 into the database header) of 1. This in turn
2758** means that the resulting database file will be readable and writable by
2759** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting,
2760** newly created databases are generally not understandable by SQLite versions
2761** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there
2762** is now scarcely any need to generate database files that are compatible
2763** all the way back to version 3.0.0, and so this setting is of little
2764** practical use, but is provided so that SQLite can continue to claim the
2765** ability to generate new database files that are compatible with version
2766** 3.0.0.
2767** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
2768** the [VACUUM] command will fail with an obscure error when attempting to
2769** process a table with generated columns and a descending index. This is
2770** not considered a bug since SQLite versions 3.3.0 and earlier do not support
2771** either generated columns or descending indexes.
2772** </dd>
2773**
2774** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]]
2775** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt>
2776** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in
2777** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears
2778** a flag that enables collection of the sqlite3_stmt_scanstatus_v2()
2779** statistics. For statistics to be collected, the flag must be set on
2780** the database handle both when the SQL statement is prepared and when it
2781** is stepped. The flag is set (collection of statistics is enabled)
2782** by default. This option takes two arguments: an integer and a pointer to
2783** an integer.. The first argument is 1, 0, or -1 to enable, disable, or
2784** leave unchanged the statement scanstatus option. If the second argument
2785** is not NULL, then the value of the statement scanstatus setting after
2786** processing the first argument is written into the integer that the second
2787** argument points to.
2788** </dd>
2789**
2790** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]]
2791** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt>
2792** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order
2793** in which tables and indexes are scanned so that the scans start at the end
2794** and work toward the beginning rather than starting at the beginning and
2795** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the
2796** same as setting [PRAGMA reverse_unordered_selects]. This option takes
2797** two arguments which are an integer and a pointer to an integer. The first
2798** argument is 1, 0, or -1 to enable, disable, or leave unchanged the
2799** reverse scan order flag, respectively. If the second argument is not NULL,
2800** then 0 or 1 is written into the integer that the second argument points to
2801** depending on if the reverse scan order flag is set after processing the
2802** first argument.
2803** </dd>
2804**
2805** </dl>
2806*/
2807#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */
2808#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
2809#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
2810#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
2811#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2812#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
2813#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */
2814#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */
2815#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */
2816#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */
2817#define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */
2818#define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */
2819#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */
2820#define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */
2821#define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */
2822#define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */
2823#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */
2824#define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */
2825#define SQLITE_DBCONFIG_STMT_SCANSTATUS 1018 /* int int* */
2826#define SQLITE_DBCONFIG_REVERSE_SCANORDER 1019 /* int int* */
2827#define SQLITE_DBCONFIG_MAX 1019 /* Largest DBCONFIG */
2828
2829/*
2830** CAPI3REF: Enable Or Disable Extended Result Codes
2831** METHOD: sqlite3
2832**
2833** ^The sqlite3_extended_result_codes() routine enables or disables the
2834** [extended result codes] feature of SQLite. ^The extended result
2835** codes are disabled by default for historical compatibility.
2836*/
2837SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2838
2839/*
2840** CAPI3REF: Last Insert Rowid
2841** METHOD: sqlite3
2842**
2843** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2844** has a unique 64-bit signed
2845** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2846** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2847** names are not also used by explicitly declared columns. ^If
2848** the table has a column of type [INTEGER PRIMARY KEY] then that column
2849** is another alias for the rowid.
2850**
2851** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2852** the most recent successful [INSERT] into a rowid table or [virtual table]
2853** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2854** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
2855** on the database connection D, then sqlite3_last_insert_rowid(D) returns
2856** zero.
2857**
2858** As well as being set automatically as rows are inserted into database
2859** tables, the value returned by this function may be set explicitly by
2860** [sqlite3_set_last_insert_rowid()]
2861**
2862** Some virtual table implementations may INSERT rows into rowid tables as
2863** part of committing a transaction (e.g. to flush data accumulated in memory
2864** to disk). In this case subsequent calls to this function return the rowid
2865** associated with these internal INSERT operations, which leads to
2866** unintuitive results. Virtual table implementations that do write to rowid
2867** tables in this way can avoid this problem by restoring the original
2868** rowid value using [sqlite3_set_last_insert_rowid()] before returning
2869** control to the user.
2870**
2871** ^(If an [INSERT] occurs within a trigger then this routine will
2872** return the [rowid] of the inserted row as long as the trigger is
2873** running. Once the trigger program ends, the value returned
2874** by this routine reverts to what it was before the trigger was fired.)^
2875**
2876** ^An [INSERT] that fails due to a constraint violation is not a
2877** successful [INSERT] and does not change the value returned by this
2878** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2879** and INSERT OR ABORT make no changes to the return value of this
2880** routine when their insertion fails. ^(When INSERT OR REPLACE
2881** encounters a constraint violation, it does not fail. The
2882** INSERT continues to completion after deleting rows that caused
2883** the constraint problem so INSERT OR REPLACE will always change
2884** the return value of this interface.)^
2885**
2886** ^For the purposes of this routine, an [INSERT] is considered to
2887** be successful even if it is subsequently rolled back.
2888**
2889** This function is accessible to SQL statements via the
2890** [last_insert_rowid() SQL function].
2891**
2892** If a separate thread performs a new [INSERT] on the same
2893** database connection while the [sqlite3_last_insert_rowid()]
2894** function is running and thus changes the last insert [rowid],
2895** then the value returned by [sqlite3_last_insert_rowid()] is
2896** unpredictable and might not equal either the old or the new
2897** last insert [rowid].
2898*/
2899SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2900
2901/*
2902** CAPI3REF: Set the Last Insert Rowid value.
2903** METHOD: sqlite3
2904**
2905** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2906** set the value returned by calling sqlite3_last_insert_rowid(D) to R
2907** without inserting a row into the database.
2908*/
2909SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2910
2911/*
2912** CAPI3REF: Count The Number Of Rows Modified
2913** METHOD: sqlite3
2914**
2915** ^These functions return the number of rows modified, inserted or
2916** deleted by the most recently completed INSERT, UPDATE or DELETE
2917** statement on the database connection specified by the only parameter.
2918** The two functions are identical except for the type of the return value
2919** and that if the number of rows modified by the most recent INSERT, UPDATE
2920** or DELETE is greater than the maximum value supported by type "int", then
2921** the return value of sqlite3_changes() is undefined. ^Executing any other
2922** type of SQL statement does not modify the value returned by these functions.
2923**
2924** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2925** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2926** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2927**
2928** Changes to a view that are intercepted by
2929** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2930** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2931** DELETE statement run on a view is always zero. Only changes made to real
2932** tables are counted.
2933**
2934** Things are more complicated if the sqlite3_changes() function is
2935** executed while a trigger program is running. This may happen if the
2936** program uses the [changes() SQL function], or if some other callback
2937** function invokes sqlite3_changes() directly. Essentially:
2938**
2939** <ul>
2940** <li> ^(Before entering a trigger program the value returned by
2941** sqlite3_changes() function is saved. After the trigger program
2942** has finished, the original value is restored.)^
2943**
2944** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2945** statement sets the value returned by sqlite3_changes()
2946** upon completion as normal. Of course, this value will not include
2947** any changes performed by sub-triggers, as the sqlite3_changes()
2948** value will be saved and restored after each sub-trigger has run.)^
2949** </ul>
2950**
2951** ^This means that if the changes() SQL function (or similar) is used
2952** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2953** returns the value as set when the calling statement began executing.
2954** ^If it is used by the second or subsequent such statement within a trigger
2955** program, the value returned reflects the number of rows modified by the
2956** previous INSERT, UPDATE or DELETE statement within the same trigger.
2957**
2958** If a separate thread makes changes on the same database connection
2959** while [sqlite3_changes()] is running then the value returned
2960** is unpredictable and not meaningful.
2961**
2962** See also:
2963** <ul>
2964** <li> the [sqlite3_total_changes()] interface
2965** <li> the [count_changes pragma]
2966** <li> the [changes() SQL function]
2967** <li> the [data_version pragma]
2968** </ul>
2969*/
2970SQLITE_API int sqlite3_changes(sqlite3*);
2971SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);
2972
2973/*
2974** CAPI3REF: Total Number Of Rows Modified
2975** METHOD: sqlite3
2976**
2977** ^These functions return the total number of rows inserted, modified or
2978** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2979** since the database connection was opened, including those executed as
2980** part of trigger programs. The two functions are identical except for the
2981** type of the return value and that if the number of rows modified by the
2982** connection exceeds the maximum value supported by type "int", then
2983** the return value of sqlite3_total_changes() is undefined. ^Executing
2984** any other type of SQL statement does not affect the value returned by
2985** sqlite3_total_changes().
2986**
2987** ^Changes made as part of [foreign key actions] are included in the
2988** count, but those made as part of REPLACE constraint resolution are
2989** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2990** are not counted.
2991**
2992** The [sqlite3_total_changes(D)] interface only reports the number
2993** of rows that changed due to SQL statement run against database
2994** connection D. Any changes by other database connections are ignored.
2995** To detect changes against a database file from other database
2996** connections use the [PRAGMA data_version] command or the
2997** [SQLITE_FCNTL_DATA_VERSION] [file control].
2998**
2999** If a separate thread makes changes on the same database connection
3000** while [sqlite3_total_changes()] is running then the value
3001** returned is unpredictable and not meaningful.
3002**
3003** See also:
3004** <ul>
3005** <li> the [sqlite3_changes()] interface
3006** <li> the [count_changes pragma]
3007** <li> the [changes() SQL function]
3008** <li> the [data_version pragma]
3009** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
3010** </ul>
3011*/
3012SQLITE_API int sqlite3_total_changes(sqlite3*);
3013SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*);
3014
3015/*
3016** CAPI3REF: Interrupt A Long-Running Query
3017** METHOD: sqlite3
3018**
3019** ^This function causes any pending database operation to abort and
3020** return at its earliest opportunity. This routine is typically
3021** called in response to a user action such as pressing "Cancel"
3022** or Ctrl-C where the user wants a long query operation to halt
3023** immediately.
3024**
3025** ^It is safe to call this routine from a thread different from the
3026** thread that is currently running the database operation. But it
3027** is not safe to call this routine with a [database connection] that
3028** is closed or might close before sqlite3_interrupt() returns.
3029**
3030** ^If an SQL operation is very nearly finished at the time when
3031** sqlite3_interrupt() is called, then it might not have an opportunity
3032** to be interrupted and might continue to completion.
3033**
3034** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
3035** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
3036** that is inside an explicit transaction, then the entire transaction
3037** will be rolled back automatically.
3038**
3039** ^The sqlite3_interrupt(D) call is in effect until all currently running
3040** SQL statements on [database connection] D complete. ^Any new SQL statements
3041** that are started after the sqlite3_interrupt() call and before the
3042** running statement count reaches zero are interrupted as if they had been
3043** running prior to the sqlite3_interrupt() call. ^New SQL statements
3044** that are started after the running statement count reaches zero are
3045** not effected by the sqlite3_interrupt().
3046** ^A call to sqlite3_interrupt(D) that occurs when there are no running
3047** SQL statements is a no-op and has no effect on SQL statements
3048** that are started after the sqlite3_interrupt() call returns.
3049**
3050** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether
3051** or not an interrupt is currently in effect for [database connection] D.
3052** It returns 1 if an interrupt is currently in effect, or 0 otherwise.
3053*/
3054SQLITE_API void sqlite3_interrupt(sqlite3*);
3055SQLITE_API int sqlite3_is_interrupted(sqlite3*);
3056
3057/*
3058** CAPI3REF: Determine If An SQL Statement Is Complete
3059**
3060** These routines are useful during command-line input to determine if the
3061** currently entered text seems to form a complete SQL statement or
3062** if additional input is needed before sending the text into
3063** SQLite for parsing. ^These routines return 1 if the input string
3064** appears to be a complete SQL statement. ^A statement is judged to be
3065** complete if it ends with a semicolon token and is not a prefix of a
3066** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
3067** string literals or quoted identifier names or comments are not
3068** independent tokens (they are part of the token in which they are
3069** embedded) and thus do not count as a statement terminator. ^Whitespace
3070** and comments that follow the final semicolon are ignored.
3071**
3072** ^These routines return 0 if the statement is incomplete. ^If a
3073** memory allocation fails, then SQLITE_NOMEM is returned.
3074**
3075** ^These routines do not parse the SQL statements thus
3076** will not detect syntactically incorrect SQL.
3077**
3078** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
3079** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
3080** automatically by sqlite3_complete16(). If that initialization fails,
3081** then the return value from sqlite3_complete16() will be non-zero
3082** regardless of whether or not the input SQL is complete.)^
3083**
3084** The input to [sqlite3_complete()] must be a zero-terminated
3085** UTF-8 string.
3086**
3087** The input to [sqlite3_complete16()] must be a zero-terminated
3088** UTF-16 string in native byte order.
3089*/
3090SQLITE_API int sqlite3_complete(const char *sql);
3091SQLITE_API int sqlite3_complete16(const void *sql);
3092
3093/*
3094** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
3095** KEYWORDS: {busy-handler callback} {busy handler}
3096** METHOD: sqlite3
3097**
3098** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
3099** that might be invoked with argument P whenever
3100** an attempt is made to access a database table associated with
3101** [database connection] D when another thread
3102** or process has the table locked.
3103** The sqlite3_busy_handler() interface is used to implement
3104** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
3105**
3106** ^If the busy callback is NULL, then [SQLITE_BUSY]
3107** is returned immediately upon encountering the lock. ^If the busy callback
3108** is not NULL, then the callback might be invoked with two arguments.
3109**
3110** ^The first argument to the busy handler is a copy of the void* pointer which
3111** is the third argument to sqlite3_busy_handler(). ^The second argument to
3112** the busy handler callback is the number of times that the busy handler has
3113** been invoked previously for the same locking event. ^If the
3114** busy callback returns 0, then no additional attempts are made to
3115** access the database and [SQLITE_BUSY] is returned
3116** to the application.
3117** ^If the callback returns non-zero, then another attempt
3118** is made to access the database and the cycle repeats.
3119**
3120** The presence of a busy handler does not guarantee that it will be invoked
3121** when there is lock contention. ^If SQLite determines that invoking the busy
3122** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
3123** to the application instead of invoking the
3124** busy handler.
3125** Consider a scenario where one process is holding a read lock that
3126** it is trying to promote to a reserved lock and
3127** a second process is holding a reserved lock that it is trying
3128** to promote to an exclusive lock. The first process cannot proceed
3129** because it is blocked by the second and the second process cannot
3130** proceed because it is blocked by the first. If both processes
3131** invoke the busy handlers, neither will make any progress. Therefore,
3132** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
3133** will induce the first process to release its read lock and allow
3134** the second process to proceed.
3135**
3136** ^The default busy callback is NULL.
3137**
3138** ^(There can only be a single busy handler defined for each
3139** [database connection]. Setting a new busy handler clears any
3140** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
3141** or evaluating [PRAGMA busy_timeout=N] will change the
3142** busy handler and thus clear any previously set busy handler.
3143**
3144** The busy callback should not take any actions which modify the
3145** database connection that invoked the busy handler. In other words,
3146** the busy handler is not reentrant. Any such actions
3147** result in undefined behavior.
3148**
3149** A busy handler must not close the database connection
3150** or [prepared statement] that invoked the busy handler.
3151*/
3152SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
3153
3154/*
3155** CAPI3REF: Set A Busy Timeout
3156** METHOD: sqlite3
3157**
3158** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
3159** for a specified amount of time when a table is locked. ^The handler
3160** will sleep multiple times until at least "ms" milliseconds of sleeping
3161** have accumulated. ^After at least "ms" milliseconds of sleeping,
3162** the handler returns 0 which causes [sqlite3_step()] to return
3163** [SQLITE_BUSY].
3164**
3165** ^Calling this routine with an argument less than or equal to zero
3166** turns off all busy handlers.
3167**
3168** ^(There can only be a single busy handler for a particular
3169** [database connection] at any given moment. If another busy handler
3170** was defined (using [sqlite3_busy_handler()]) prior to calling
3171** this routine, that other busy handler is cleared.)^
3172**
3173** See also: [PRAGMA busy_timeout]
3174*/
3175SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
3176
3177/*
3178** CAPI3REF: Convenience Routines For Running Queries
3179** METHOD: sqlite3
3180**
3181** This is a legacy interface that is preserved for backwards compatibility.
3182** Use of this interface is not recommended.
3183**
3184** Definition: A <b>result table</b> is memory data structure created by the
3185** [sqlite3_get_table()] interface. A result table records the
3186** complete query results from one or more queries.
3187**
3188** The table conceptually has a number of rows and columns. But
3189** these numbers are not part of the result table itself. These
3190** numbers are obtained separately. Let N be the number of rows
3191** and M be the number of columns.
3192**
3193** A result table is an array of pointers to zero-terminated UTF-8 strings.
3194** There are (N+1)*M elements in the array. The first M pointers point
3195** to zero-terminated strings that contain the names of the columns.
3196** The remaining entries all point to query results. NULL values result
3197** in NULL pointers. All other values are in their UTF-8 zero-terminated
3198** string representation as returned by [sqlite3_column_text()].
3199**
3200** A result table might consist of one or more memory allocations.
3201** It is not safe to pass a result table directly to [sqlite3_free()].
3202** A result table should be deallocated using [sqlite3_free_table()].
3203**
3204** ^(As an example of the result table format, suppose a query result
3205** is as follows:
3206**
3207** <blockquote><pre>
3208** Name | Age
3209** -----------------------
3210** Alice | 43
3211** Bob | 28
3212** Cindy | 21
3213** </pre></blockquote>
3214**
3215** There are two columns (M==2) and three rows (N==3). Thus the
3216** result table has 8 entries. Suppose the result table is stored
3217** in an array named azResult. Then azResult holds this content:
3218**
3219** <blockquote><pre>
3220** azResult&#91;0] = "Name";
3221** azResult&#91;1] = "Age";
3222** azResult&#91;2] = "Alice";
3223** azResult&#91;3] = "43";
3224** azResult&#91;4] = "Bob";
3225** azResult&#91;5] = "28";
3226** azResult&#91;6] = "Cindy";
3227** azResult&#91;7] = "21";
3228** </pre></blockquote>)^
3229**
3230** ^The sqlite3_get_table() function evaluates one or more
3231** semicolon-separated SQL statements in the zero-terminated UTF-8
3232** string of its 2nd parameter and returns a result table to the
3233** pointer given in its 3rd parameter.
3234**
3235** After the application has finished with the result from sqlite3_get_table(),
3236** it must pass the result table pointer to sqlite3_free_table() in order to
3237** release the memory that was malloced. Because of the way the
3238** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
3239** function must not try to call [sqlite3_free()] directly. Only
3240** [sqlite3_free_table()] is able to release the memory properly and safely.
3241**
3242** The sqlite3_get_table() interface is implemented as a wrapper around
3243** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
3244** to any internal data structures of SQLite. It uses only the public
3245** interface defined here. As a consequence, errors that occur in the
3246** wrapper layer outside of the internal [sqlite3_exec()] call are not
3247** reflected in subsequent calls to [sqlite3_errcode()] or
3248** [sqlite3_errmsg()].
3249*/
3250SQLITE_API int sqlite3_get_table(
3251 sqlite3 *db, /* An open database */
3252 const char *zSql, /* SQL to be evaluated */
3253 char ***pazResult, /* Results of the query */
3254 int *pnRow, /* Number of result rows written here */
3255 int *pnColumn, /* Number of result columns written here */
3256 char **pzErrmsg /* Error msg written here */
3257);
3258SQLITE_API void sqlite3_free_table(char **result);
3259
3260/*
3261** CAPI3REF: Formatted String Printing Functions
3262**
3263** These routines are work-alikes of the "printf()" family of functions
3264** from the standard C library.
3265** These routines understand most of the common formatting options from
3266** the standard library printf()
3267** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
3268** See the [built-in printf()] documentation for details.
3269**
3270** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
3271** results into memory obtained from [sqlite3_malloc64()].
3272** The strings returned by these two routines should be
3273** released by [sqlite3_free()]. ^Both routines return a
3274** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
3275** memory to hold the resulting string.
3276**
3277** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
3278** the standard C library. The result is written into the
3279** buffer supplied as the second parameter whose size is given by
3280** the first parameter. Note that the order of the
3281** first two parameters is reversed from snprintf().)^ This is an
3282** historical accident that cannot be fixed without breaking
3283** backwards compatibility. ^(Note also that sqlite3_snprintf()
3284** returns a pointer to its buffer instead of the number of
3285** characters actually written into the buffer.)^ We admit that
3286** the number of characters written would be a more useful return
3287** value but we cannot change the implementation of sqlite3_snprintf()
3288** now without breaking compatibility.
3289**
3290** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
3291** guarantees that the buffer is always zero-terminated. ^The first
3292** parameter "n" is the total size of the buffer, including space for
3293** the zero terminator. So the longest string that can be completely
3294** written will be n-1 characters.
3295**
3296** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
3297**
3298** See also: [built-in printf()], [printf() SQL function]
3299*/
3300SQLITE_API char *sqlite3_mprintf(const char*,...);
3301SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
3302SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
3303SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
3304
3305/*
3306** CAPI3REF: Memory Allocation Subsystem
3307**
3308** The SQLite core uses these three routines for all of its own
3309** internal memory allocation needs. "Core" in the previous sentence
3310** does not include operating-system specific [VFS] implementation. The
3311** Windows VFS uses native malloc() and free() for some operations.
3312**
3313** ^The sqlite3_malloc() routine returns a pointer to a block
3314** of memory at least N bytes in length, where N is the parameter.
3315** ^If sqlite3_malloc() is unable to obtain sufficient free
3316** memory, it returns a NULL pointer. ^If the parameter N to
3317** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
3318** a NULL pointer.
3319**
3320** ^The sqlite3_malloc64(N) routine works just like
3321** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
3322** of a signed 32-bit integer.
3323**
3324** ^Calling sqlite3_free() with a pointer previously returned
3325** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
3326** that it might be reused. ^The sqlite3_free() routine is
3327** a no-op if is called with a NULL pointer. Passing a NULL pointer
3328** to sqlite3_free() is harmless. After being freed, memory
3329** should neither be read nor written. Even reading previously freed
3330** memory might result in a segmentation fault or other severe error.
3331** Memory corruption, a segmentation fault, or other severe error
3332** might result if sqlite3_free() is called with a non-NULL pointer that
3333** was not obtained from sqlite3_malloc() or sqlite3_realloc().
3334**
3335** ^The sqlite3_realloc(X,N) interface attempts to resize a
3336** prior memory allocation X to be at least N bytes.
3337** ^If the X parameter to sqlite3_realloc(X,N)
3338** is a NULL pointer then its behavior is identical to calling
3339** sqlite3_malloc(N).
3340** ^If the N parameter to sqlite3_realloc(X,N) is zero or
3341** negative then the behavior is exactly the same as calling
3342** sqlite3_free(X).
3343** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
3344** of at least N bytes in size or NULL if insufficient memory is available.
3345** ^If M is the size of the prior allocation, then min(N,M) bytes
3346** of the prior allocation are copied into the beginning of buffer returned
3347** by sqlite3_realloc(X,N) and the prior allocation is freed.
3348** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
3349** prior allocation is not freed.
3350**
3351** ^The sqlite3_realloc64(X,N) interfaces works the same as
3352** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
3353** of a 32-bit signed integer.
3354**
3355** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
3356** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
3357** sqlite3_msize(X) returns the size of that memory allocation in bytes.
3358** ^The value returned by sqlite3_msize(X) might be larger than the number
3359** of bytes requested when X was allocated. ^If X is a NULL pointer then
3360** sqlite3_msize(X) returns zero. If X points to something that is not
3361** the beginning of memory allocation, or if it points to a formerly
3362** valid memory allocation that has now been freed, then the behavior
3363** of sqlite3_msize(X) is undefined and possibly harmful.
3364**
3365** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
3366** sqlite3_malloc64(), and sqlite3_realloc64()
3367** is always aligned to at least an 8 byte boundary, or to a
3368** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
3369** option is used.
3370**
3371** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
3372** must be either NULL or else pointers obtained from a prior
3373** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
3374** not yet been released.
3375**
3376** The application must not read or write any part of
3377** a block of memory after it has been released using
3378** [sqlite3_free()] or [sqlite3_realloc()].
3379*/
3380SQLITE_API void *sqlite3_malloc(int);
3381SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
3382SQLITE_API void *sqlite3_realloc(void*, int);
3383SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
3384SQLITE_API void sqlite3_free(void*);
3385SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
3386
3387/*
3388** CAPI3REF: Memory Allocator Statistics
3389**
3390** SQLite provides these two interfaces for reporting on the status
3391** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
3392** routines, which form the built-in memory allocation subsystem.
3393**
3394** ^The [sqlite3_memory_used()] routine returns the number of bytes
3395** of memory currently outstanding (malloced but not freed).
3396** ^The [sqlite3_memory_highwater()] routine returns the maximum
3397** value of [sqlite3_memory_used()] since the high-water mark
3398** was last reset. ^The values returned by [sqlite3_memory_used()] and
3399** [sqlite3_memory_highwater()] include any overhead
3400** added by SQLite in its implementation of [sqlite3_malloc()],
3401** but not overhead added by the any underlying system library
3402** routines that [sqlite3_malloc()] may call.
3403**
3404** ^The memory high-water mark is reset to the current value of
3405** [sqlite3_memory_used()] if and only if the parameter to
3406** [sqlite3_memory_highwater()] is true. ^The value returned
3407** by [sqlite3_memory_highwater(1)] is the high-water mark
3408** prior to the reset.
3409*/
3410SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
3411SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
3412
3413/*
3414** CAPI3REF: Pseudo-Random Number Generator
3415**
3416** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
3417** select random [ROWID | ROWIDs] when inserting new records into a table that
3418** already uses the largest possible [ROWID]. The PRNG is also used for
3419** the built-in random() and randomblob() SQL functions. This interface allows
3420** applications to access the same PRNG for other purposes.
3421**
3422** ^A call to this routine stores N bytes of randomness into buffer P.
3423** ^The P parameter can be a NULL pointer.
3424**
3425** ^If this routine has not been previously called or if the previous
3426** call had N less than one or a NULL pointer for P, then the PRNG is
3427** seeded using randomness obtained from the xRandomness method of
3428** the default [sqlite3_vfs] object.
3429** ^If the previous call to this routine had an N of 1 or more and a
3430** non-NULL P then the pseudo-randomness is generated
3431** internally and without recourse to the [sqlite3_vfs] xRandomness
3432** method.
3433*/
3434SQLITE_API void sqlite3_randomness(int N, void *P);
3435
3436/*
3437** CAPI3REF: Compile-Time Authorization Callbacks
3438** METHOD: sqlite3
3439** KEYWORDS: {authorizer callback}
3440**
3441** ^This routine registers an authorizer callback with a particular
3442** [database connection], supplied in the first argument.
3443** ^The authorizer callback is invoked as SQL statements are being compiled
3444** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
3445** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
3446** and [sqlite3_prepare16_v3()]. ^At various
3447** points during the compilation process, as logic is being created
3448** to perform various actions, the authorizer callback is invoked to
3449** see if those actions are allowed. ^The authorizer callback should
3450** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
3451** specific action but allow the SQL statement to continue to be
3452** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
3453** rejected with an error. ^If the authorizer callback returns
3454** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
3455** then the [sqlite3_prepare_v2()] or equivalent call that triggered
3456** the authorizer will fail with an error message.
3457**
3458** When the callback returns [SQLITE_OK], that means the operation
3459** requested is ok. ^When the callback returns [SQLITE_DENY], the
3460** [sqlite3_prepare_v2()] or equivalent call that triggered the
3461** authorizer will fail with an error message explaining that
3462** access is denied.
3463**
3464** ^The first parameter to the authorizer callback is a copy of the third
3465** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
3466** to the callback is an integer [SQLITE_COPY | action code] that specifies
3467** the particular action to be authorized. ^The third through sixth parameters
3468** to the callback are either NULL pointers or zero-terminated strings
3469** that contain additional details about the action to be authorized.
3470** Applications must always be prepared to encounter a NULL pointer in any
3471** of the third through the sixth parameters of the authorization callback.
3472**
3473** ^If the action code is [SQLITE_READ]
3474** and the callback returns [SQLITE_IGNORE] then the
3475** [prepared statement] statement is constructed to substitute
3476** a NULL value in place of the table column that would have
3477** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
3478** return can be used to deny an untrusted user access to individual
3479** columns of a table.
3480** ^When a table is referenced by a [SELECT] but no column values are
3481** extracted from that table (for example in a query like
3482** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
3483** is invoked once for that table with a column name that is an empty string.
3484** ^If the action code is [SQLITE_DELETE] and the callback returns
3485** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
3486** [truncate optimization] is disabled and all rows are deleted individually.
3487**
3488** An authorizer is used when [sqlite3_prepare | preparing]
3489** SQL statements from an untrusted source, to ensure that the SQL statements
3490** do not try to access data they are not allowed to see, or that they do not
3491** try to execute malicious statements that damage the database. For
3492** example, an application may allow a user to enter arbitrary
3493** SQL queries for evaluation by a database. But the application does
3494** not want the user to be able to make arbitrary changes to the
3495** database. An authorizer could then be put in place while the
3496** user-entered SQL is being [sqlite3_prepare | prepared] that
3497** disallows everything except [SELECT] statements.
3498**
3499** Applications that need to process SQL from untrusted sources
3500** might also consider lowering resource limits using [sqlite3_limit()]
3501** and limiting database size using the [max_page_count] [PRAGMA]
3502** in addition to using an authorizer.
3503**
3504** ^(Only a single authorizer can be in place on a database connection
3505** at a time. Each call to sqlite3_set_authorizer overrides the
3506** previous call.)^ ^Disable the authorizer by installing a NULL callback.
3507** The authorizer is disabled by default.
3508**
3509** The authorizer callback must not do anything that will modify
3510** the database connection that invoked the authorizer callback.
3511** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3512** database connections for the meaning of "modify" in this paragraph.
3513**
3514** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
3515** statement might be re-prepared during [sqlite3_step()] due to a
3516** schema change. Hence, the application should ensure that the
3517** correct authorizer callback remains in place during the [sqlite3_step()].
3518**
3519** ^Note that the authorizer callback is invoked only during
3520** [sqlite3_prepare()] or its variants. Authorization is not
3521** performed during statement evaluation in [sqlite3_step()], unless
3522** as stated in the previous paragraph, sqlite3_step() invokes
3523** sqlite3_prepare_v2() to reprepare a statement after a schema change.
3524*/
3525SQLITE_API int sqlite3_set_authorizer(
3526 sqlite3*,
3527 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
3528 void *pUserData
3529);
3530
3531/*
3532** CAPI3REF: Authorizer Return Codes
3533**
3534** The [sqlite3_set_authorizer | authorizer callback function] must
3535** return either [SQLITE_OK] or one of these two constants in order
3536** to signal SQLite whether or not the action is permitted. See the
3537** [sqlite3_set_authorizer | authorizer documentation] for additional
3538** information.
3539**
3540** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
3541** returned from the [sqlite3_vtab_on_conflict()] interface.
3542*/
3543#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
3544#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
3545
3546/*
3547** CAPI3REF: Authorizer Action Codes
3548**
3549** The [sqlite3_set_authorizer()] interface registers a callback function
3550** that is invoked to authorize certain SQL statement actions. The
3551** second parameter to the callback is an integer code that specifies
3552** what action is being authorized. These are the integer action codes that
3553** the authorizer callback may be passed.
3554**
3555** These action code values signify what kind of operation is to be
3556** authorized. The 3rd and 4th parameters to the authorization
3557** callback function will be parameters or NULL depending on which of these
3558** codes is used as the second parameter. ^(The 5th parameter to the
3559** authorizer callback is the name of the database ("main", "temp",
3560** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
3561** is the name of the inner-most trigger or view that is responsible for
3562** the access attempt or NULL if this access attempt is directly from
3563** top-level SQL code.
3564*/
3565/******************************************* 3rd ************ 4th ***********/
3566#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
3567#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
3568#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
3569#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
3570#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
3571#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
3572#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
3573#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
3574#define SQLITE_DELETE 9 /* Table Name NULL */
3575#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
3576#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
3577#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
3578#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
3579#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
3580#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
3581#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
3582#define SQLITE_DROP_VIEW 17 /* View Name NULL */
3583#define SQLITE_INSERT 18 /* Table Name NULL */
3584#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
3585#define SQLITE_READ 20 /* Table Name Column Name */
3586#define SQLITE_SELECT 21 /* NULL NULL */
3587#define SQLITE_TRANSACTION 22 /* Operation NULL */
3588#define SQLITE_UPDATE 23 /* Table Name Column Name */
3589#define SQLITE_ATTACH 24 /* Filename NULL */
3590#define SQLITE_DETACH 25 /* Database Name NULL */
3591#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
3592#define SQLITE_REINDEX 27 /* Index Name NULL */
3593#define SQLITE_ANALYZE 28 /* Table Name NULL */
3594#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
3595#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
3596#define SQLITE_FUNCTION 31 /* NULL Function Name */
3597#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
3598#define SQLITE_COPY 0 /* No longer used */
3599#define SQLITE_RECURSIVE 33 /* NULL NULL */
3600
3601/*
3602** CAPI3REF: Tracing And Profiling Functions
3603** METHOD: sqlite3
3604**
3605** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
3606** instead of the routines described here.
3607**
3608** These routines register callback functions that can be used for
3609** tracing and profiling the execution of SQL statements.
3610**
3611** ^The callback function registered by sqlite3_trace() is invoked at
3612** various times when an SQL statement is being run by [sqlite3_step()].
3613** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
3614** SQL statement text as the statement first begins executing.
3615** ^(Additional sqlite3_trace() callbacks might occur
3616** as each triggered subprogram is entered. The callbacks for triggers
3617** contain a UTF-8 SQL comment that identifies the trigger.)^
3618**
3619** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
3620** the length of [bound parameter] expansion in the output of sqlite3_trace().
3621**
3622** ^The callback function registered by sqlite3_profile() is invoked
3623** as each SQL statement finishes. ^The profile callback contains
3624** the original statement text and an estimate of wall-clock time
3625** of how long that statement took to run. ^The profile callback
3626** time is in units of nanoseconds, however the current implementation
3627** is only capable of millisecond resolution so the six least significant
3628** digits in the time are meaningless. Future versions of SQLite
3629** might provide greater resolution on the profiler callback. Invoking
3630** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
3631** profile callback.
3632*/
3633SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
3634 void(*xTrace)(void*,const char*), void*);
3635SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
3636 void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
3637
3638/*
3639** CAPI3REF: SQL Trace Event Codes
3640** KEYWORDS: SQLITE_TRACE
3641**
3642** These constants identify classes of events that can be monitored
3643** using the [sqlite3_trace_v2()] tracing logic. The M argument
3644** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
3645** the following constants. ^The first argument to the trace callback
3646** is one of the following constants.
3647**
3648** New tracing constants may be added in future releases.
3649**
3650** ^A trace callback has four arguments: xCallback(T,C,P,X).
3651** ^The T argument is one of the integer type codes above.
3652** ^The C argument is a copy of the context pointer passed in as the
3653** fourth argument to [sqlite3_trace_v2()].
3654** The P and X arguments are pointers whose meanings depend on T.
3655**
3656** <dl>
3657** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
3658** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
3659** first begins running and possibly at other times during the
3660** execution of the prepared statement, such as at the start of each
3661** trigger subprogram. ^The P argument is a pointer to the
3662** [prepared statement]. ^The X argument is a pointer to a string which
3663** is the unexpanded SQL text of the prepared statement or an SQL comment
3664** that indicates the invocation of a trigger. ^The callback can compute
3665** the same text that would have been returned by the legacy [sqlite3_trace()]
3666** interface by using the X argument when X begins with "--" and invoking
3667** [sqlite3_expanded_sql(P)] otherwise.
3668**
3669** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
3670** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
3671** information as is provided by the [sqlite3_profile()] callback.
3672** ^The P argument is a pointer to the [prepared statement] and the
3673** X argument points to a 64-bit integer which is approximately
3674** the number of nanoseconds that the prepared statement took to run.
3675** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
3676**
3677** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
3678** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
3679** statement generates a single row of result.
3680** ^The P argument is a pointer to the [prepared statement] and the
3681** X argument is unused.
3682**
3683** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
3684** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
3685** connection closes.
3686** ^The P argument is a pointer to the [database connection] object
3687** and the X argument is unused.
3688** </dl>
3689*/
3690#define SQLITE_TRACE_STMT 0x01
3691#define SQLITE_TRACE_PROFILE 0x02
3692#define SQLITE_TRACE_ROW 0x04
3693#define SQLITE_TRACE_CLOSE 0x08
3694
3695/*
3696** CAPI3REF: SQL Trace Hook
3697** METHOD: sqlite3
3698**
3699** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
3700** function X against [database connection] D, using property mask M
3701** and context pointer P. ^If the X callback is
3702** NULL or if the M mask is zero, then tracing is disabled. The
3703** M argument should be the bitwise OR-ed combination of
3704** zero or more [SQLITE_TRACE] constants.
3705**
3706** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P)
3707** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or
3708** sqlite3_trace_v2(D,M,X,P) for the [database connection] D. Each
3709** database connection may have at most one trace callback.
3710**
3711** ^The X callback is invoked whenever any of the events identified by
3712** mask M occur. ^The integer return value from the callback is currently
3713** ignored, though this may change in future releases. Callback
3714** implementations should return zero to ensure future compatibility.
3715**
3716** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
3717** ^The T argument is one of the [SQLITE_TRACE]
3718** constants to indicate why the callback was invoked.
3719** ^The C argument is a copy of the context pointer.
3720** The P and X arguments are pointers whose meanings depend on T.
3721**
3722** The sqlite3_trace_v2() interface is intended to replace the legacy
3723** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3724** are deprecated.
3725*/
3726SQLITE_API int sqlite3_trace_v2(
3727 sqlite3*,
3728 unsigned uMask,
3729 int(*xCallback)(unsigned,void*,void*,void*),
3730 void *pCtx
3731);
3732
3733/*
3734** CAPI3REF: Query Progress Callbacks
3735** METHOD: sqlite3
3736**
3737** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3738** function X to be invoked periodically during long running calls to
3739** [sqlite3_step()] and [sqlite3_prepare()] and similar for
3740** database connection D. An example use for this
3741** interface is to keep a GUI updated during a large query.
3742**
3743** ^The parameter P is passed through as the only parameter to the
3744** callback function X. ^The parameter N is the approximate number of
3745** [virtual machine instructions] that are evaluated between successive
3746** invocations of the callback X. ^If N is less than one then the progress
3747** handler is disabled.
3748**
3749** ^Only a single progress handler may be defined at one time per
3750** [database connection]; setting a new progress handler cancels the
3751** old one. ^Setting parameter X to NULL disables the progress handler.
3752** ^The progress handler is also disabled by setting N to a value less
3753** than 1.
3754**
3755** ^If the progress callback returns non-zero, the operation is
3756** interrupted. This feature can be used to implement a
3757** "Cancel" button on a GUI progress dialog box.
3758**
3759** The progress handler callback must not do anything that will modify
3760** the database connection that invoked the progress handler.
3761** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3762** database connections for the meaning of "modify" in this paragraph.
3763**
3764** The progress handler callback would originally only be invoked from the
3765** bytecode engine. It still might be invoked during [sqlite3_prepare()]
3766** and similar because those routines might force a reparse of the schema
3767** which involves running the bytecode engine. However, beginning with
3768** SQLite version 3.41.0, the progress handler callback might also be
3769** invoked directly from [sqlite3_prepare()] while analyzing and generating
3770** code for complex queries.
3771*/
3772SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3773
3774/*
3775** CAPI3REF: Opening A New Database Connection
3776** CONSTRUCTOR: sqlite3
3777**
3778** ^These routines open an SQLite database file as specified by the
3779** filename argument. ^The filename argument is interpreted as UTF-8 for
3780** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3781** order for sqlite3_open16(). ^(A [database connection] handle is usually
3782** returned in *ppDb, even if an error occurs. The only exception is that
3783** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3784** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3785** object.)^ ^(If the database is opened (and/or created) successfully, then
3786** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
3787** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3788** an English language description of the error following a failure of any
3789** of the sqlite3_open() routines.
3790**
3791** ^The default encoding will be UTF-8 for databases created using
3792** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases
3793** created using sqlite3_open16() will be UTF-16 in the native byte order.
3794**
3795** Whether or not an error occurs when it is opened, resources
3796** associated with the [database connection] handle should be released by
3797** passing it to [sqlite3_close()] when it is no longer required.
3798**
3799** The sqlite3_open_v2() interface works like sqlite3_open()
3800** except that it accepts two additional parameters for additional control
3801** over the new database connection. ^(The flags parameter to
3802** sqlite3_open_v2() must include, at a minimum, one of the following
3803** three flag combinations:)^
3804**
3805** <dl>
3806** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3807** <dd>The database is opened in read-only mode. If the database does
3808** not already exist, an error is returned.</dd>)^
3809**
3810** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3811** <dd>The database is opened for reading and writing if possible, or
3812** reading only if the file is write protected by the operating
3813** system. In either case the database must already exist, otherwise
3814** an error is returned. For historical reasons, if opening in
3815** read-write mode fails due to OS-level permissions, an attempt is
3816** made to open it in read-only mode. [sqlite3_db_readonly()] can be
3817** used to determine whether the database is actually
3818** read-write.</dd>)^
3819**
3820** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3821** <dd>The database is opened for reading and writing, and is created if
3822** it does not already exist. This is the behavior that is always used for
3823** sqlite3_open() and sqlite3_open16().</dd>)^
3824** </dl>
3825**
3826** In addition to the required flags, the following optional flags are
3827** also supported:
3828**
3829** <dl>
3830** ^(<dt>[SQLITE_OPEN_URI]</dt>
3831** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
3832**
3833** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
3834** <dd>The database will be opened as an in-memory database. The database
3835** is named by the "filename" argument for the purposes of cache-sharing,
3836** if shared cache mode is enabled, but the "filename" is otherwise ignored.
3837** </dd>)^
3838**
3839** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
3840** <dd>The new database connection will use the "multi-thread"
3841** [threading mode].)^ This means that separate threads are allowed
3842** to use SQLite at the same time, as long as each thread is using
3843** a different [database connection].
3844**
3845** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
3846** <dd>The new database connection will use the "serialized"
3847** [threading mode].)^ This means the multiple threads can safely
3848** attempt to use the same database connection at the same time.
3849** (Mutexes will block any actual concurrency, but in this mode
3850** there is no harm in trying.)
3851**
3852** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
3853** <dd>The database is opened [shared cache] enabled, overriding
3854** the default shared cache setting provided by
3855** [sqlite3_enable_shared_cache()].)^
3856** The [use of shared cache mode is discouraged] and hence shared cache
3857** capabilities may be omitted from many builds of SQLite. In such cases,
3858** this option is a no-op.
3859**
3860** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
3861** <dd>The database is opened [shared cache] disabled, overriding
3862** the default shared cache setting provided by
3863** [sqlite3_enable_shared_cache()].)^
3864**
3865** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
3866** <dd>The database connection comes up in "extended result code mode".
3867** In other words, the database behaves has if
3868** [sqlite3_extended_result_codes(db,1)] where called on the database
3869** connection as soon as the connection is created. In addition to setting
3870** the extended result code mode, this flag also causes [sqlite3_open_v2()]
3871** to return an extended result code.</dd>
3872**
3873** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
3874** <dd>The database filename is not allowed to contain a symbolic link</dd>
3875** </dl>)^
3876**
3877** If the 3rd parameter to sqlite3_open_v2() is not one of the
3878** required combinations shown above optionally combined with other
3879** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3880** then the behavior is undefined. Historic versions of SQLite
3881** have silently ignored surplus bits in the flags parameter to
3882** sqlite3_open_v2(), however that behavior might not be carried through
3883** into future versions of SQLite and so applications should not rely
3884** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op
3885** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause
3886** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE
3887** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not
3888** by sqlite3_open_v2().
3889**
3890** ^The fourth parameter to sqlite3_open_v2() is the name of the
3891** [sqlite3_vfs] object that defines the operating system interface that
3892** the new database connection should use. ^If the fourth parameter is
3893** a NULL pointer then the default [sqlite3_vfs] object is used.
3894**
3895** ^If the filename is ":memory:", then a private, temporary in-memory database
3896** is created for the connection. ^This in-memory database will vanish when
3897** the database connection is closed. Future versions of SQLite might
3898** make use of additional special filenames that begin with the ":" character.
3899** It is recommended that when a database filename actually does begin with
3900** a ":" character you should prefix the filename with a pathname such as
3901** "./" to avoid ambiguity.
3902**
3903** ^If the filename is an empty string, then a private, temporary
3904** on-disk database will be created. ^This private database will be
3905** automatically deleted as soon as the database connection is closed.
3906**
3907** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3908**
3909** ^If [URI filename] interpretation is enabled, and the filename argument
3910** begins with "file:", then the filename is interpreted as a URI. ^URI
3911** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3912** set in the third argument to sqlite3_open_v2(), or if it has
3913** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3914** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3915** URI filename interpretation is turned off
3916** by default, but future releases of SQLite might enable URI filename
3917** interpretation by default. See "[URI filenames]" for additional
3918** information.
3919**
3920** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3921** authority, then it must be either an empty string or the string
3922** "localhost". ^If the authority is not an empty string or "localhost", an
3923** error is returned to the caller. ^The fragment component of a URI, if
3924** present, is ignored.
3925**
3926** ^SQLite uses the path component of the URI as the name of the disk file
3927** which contains the database. ^If the path begins with a '/' character,
3928** then it is interpreted as an absolute path. ^If the path does not begin
3929** with a '/' (meaning that the authority section is omitted from the URI)
3930** then the path is interpreted as a relative path.
3931** ^(On windows, the first component of an absolute path
3932** is a drive specification (e.g. "C:").)^
3933**
3934** [[core URI query parameters]]
3935** The query component of a URI may contain parameters that are interpreted
3936** either by SQLite itself, or by a [VFS | custom VFS implementation].
3937** SQLite and its built-in [VFSes] interpret the
3938** following query parameters:
3939**
3940** <ul>
3941** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3942** a VFS object that provides the operating system interface that should
3943** be used to access the database file on disk. ^If this option is set to
3944** an empty string the default VFS object is used. ^Specifying an unknown
3945** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3946** present, then the VFS specified by the option takes precedence over
3947** the value passed as the fourth parameter to sqlite3_open_v2().
3948**
3949** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3950** "rwc", or "memory". Attempting to set it to any other value is
3951** an error)^.
3952** ^If "ro" is specified, then the database is opened for read-only
3953** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3954** third argument to sqlite3_open_v2(). ^If the mode option is set to
3955** "rw", then the database is opened for read-write (but not create)
3956** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3957** been set. ^Value "rwc" is equivalent to setting both
3958** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
3959** set to "memory" then a pure [in-memory database] that never reads
3960** or writes from disk is used. ^It is an error to specify a value for
3961** the mode parameter that is less restrictive than that specified by
3962** the flags passed in the third parameter to sqlite3_open_v2().
3963**
3964** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3965** "private". ^Setting it to "shared" is equivalent to setting the
3966** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3967** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3968** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3969** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3970** a URI filename, its value overrides any behavior requested by setting
3971** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3972**
3973** <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3974** [powersafe overwrite] property does or does not apply to the
3975** storage media on which the database file resides.
3976**
3977** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3978** which if set disables file locking in rollback journal modes. This
3979** is useful for accessing a database on a filesystem that does not
3980** support locking. Caution: Database corruption might result if two
3981** or more processes write to the same database and any one of those
3982** processes uses nolock=1.
3983**
3984** <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3985** parameter that indicates that the database file is stored on
3986** read-only media. ^When immutable is set, SQLite assumes that the
3987** database file cannot be changed, even by a process with higher
3988** privilege, and so the database is opened read-only and all locking
3989** and change detection is disabled. Caution: Setting the immutable
3990** property on a database file that does in fact change can result
3991** in incorrect query results and/or [SQLITE_CORRUPT] errors.
3992** See also: [SQLITE_IOCAP_IMMUTABLE].
3993**
3994** </ul>
3995**
3996** ^Specifying an unknown parameter in the query component of a URI is not an
3997** error. Future versions of SQLite might understand additional query
3998** parameters. See "[query parameters with special meaning to SQLite]" for
3999** additional information.
4000**
4001** [[URI filename examples]] <h3>URI filename examples</h3>
4002**
4003** <table border="1" align=center cellpadding=5>
4004** <tr><th> URI filenames <th> Results
4005** <tr><td> file:data.db <td>
4006** Open the file "data.db" in the current directory.
4007** <tr><td> file:/home/fred/data.db<br>
4008** file:///home/fred/data.db <br>
4009** file://localhost/home/fred/data.db <br> <td>
4010** Open the database file "/home/fred/data.db".
4011** <tr><td> file://darkstar/home/fred/data.db <td>
4012** An error. "darkstar" is not a recognized authority.
4013** <tr><td style="white-space:nowrap">
4014** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
4015** <td> Windows only: Open the file "data.db" on fred's desktop on drive
4016** C:. Note that the %20 escaping in this example is not strictly
4017** necessary - space characters can be used literally
4018** in URI filenames.
4019** <tr><td> file:data.db?mode=ro&cache=private <td>
4020** Open file "data.db" in the current directory for read-only access.
4021** Regardless of whether or not shared-cache mode is enabled by
4022** default, use a private cache.
4023** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
4024** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
4025** that uses dot-files in place of posix advisory locking.
4026** <tr><td> file:data.db?mode=readonly <td>
4027** An error. "readonly" is not a valid option for the "mode" parameter.
4028** Use "ro" instead: "file:data.db?mode=ro".
4029** </table>
4030**
4031** ^URI hexadecimal escape sequences (%HH) are supported within the path and
4032** query components of a URI. A hexadecimal escape sequence consists of a
4033** percent sign - "%" - followed by exactly two hexadecimal digits
4034** specifying an octet value. ^Before the path or query components of a
4035** URI filename are interpreted, they are encoded using UTF-8 and all
4036** hexadecimal escape sequences replaced by a single byte containing the
4037** corresponding octet. If this process generates an invalid UTF-8 encoding,
4038** the results are undefined.
4039**
4040** <b>Note to Windows users:</b> The encoding used for the filename argument
4041** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
4042** codepage is currently defined. Filenames containing international
4043** characters must be converted to UTF-8 prior to passing them into
4044** sqlite3_open() or sqlite3_open_v2().
4045**
4046** <b>Note to Windows Runtime users:</b> The temporary directory must be set
4047** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
4048** features that require the use of temporary files may fail.
4049**
4050** See also: [sqlite3_temp_directory]
4051*/
4052SQLITE_API int sqlite3_open(
4053 const char *filename, /* Database filename (UTF-8) */
4054 sqlite3 **ppDb /* OUT: SQLite db handle */
4055);
4056SQLITE_API int sqlite3_open16(
4057 const void *filename, /* Database filename (UTF-16) */
4058 sqlite3 **ppDb /* OUT: SQLite db handle */
4059);
4060SQLITE_API int sqlite3_open_v2(
4061 const char *filename, /* Database filename (UTF-8) */
4062 sqlite3 **ppDb, /* OUT: SQLite db handle */
4063 int flags, /* Flags */
4064 const char *zVfs /* Name of VFS module to use */
4065);
4066
4067/*
4068** CAPI3REF: Obtain Values For URI Parameters
4069**
4070** These are utility routines, useful to [VFS|custom VFS implementations],
4071** that check if a database file was a URI that contained a specific query
4072** parameter, and if so obtains the value of that query parameter.
4073**
4074** The first parameter to these interfaces (hereafter referred to
4075** as F) must be one of:
4076** <ul>
4077** <li> A database filename pointer created by the SQLite core and
4078** passed into the xOpen() method of a VFS implementation, or
4079** <li> A filename obtained from [sqlite3_db_filename()], or
4080** <li> A new filename constructed using [sqlite3_create_filename()].
4081** </ul>
4082** If the F parameter is not one of the above, then the behavior is
4083** undefined and probably undesirable. Older versions of SQLite were
4084** more tolerant of invalid F parameters than newer versions.
4085**
4086** If F is a suitable filename (as described in the previous paragraph)
4087** and if P is the name of the query parameter, then
4088** sqlite3_uri_parameter(F,P) returns the value of the P
4089** parameter if it exists or a NULL pointer if P does not appear as a
4090** query parameter on F. If P is a query parameter of F and it
4091** has no explicit value, then sqlite3_uri_parameter(F,P) returns
4092** a pointer to an empty string.
4093**
4094** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
4095** parameter and returns true (1) or false (0) according to the value
4096** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
4097** value of query parameter P is one of "yes", "true", or "on" in any
4098** case or if the value begins with a non-zero number. The
4099** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
4100** query parameter P is one of "no", "false", or "off" in any case or
4101** if the value begins with a numeric zero. If P is not a query
4102** parameter on F or if the value of P does not match any of the
4103** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
4104**
4105** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
4106** 64-bit signed integer and returns that integer, or D if P does not
4107** exist. If the value of P is something other than an integer, then
4108** zero is returned.
4109**
4110** The sqlite3_uri_key(F,N) returns a pointer to the name (not
4111** the value) of the N-th query parameter for filename F, or a NULL
4112** pointer if N is less than zero or greater than the number of query
4113** parameters minus 1. The N value is zero-based so N should be 0 to obtain
4114** the name of the first query parameter, 1 for the second parameter, and
4115** so forth.
4116**
4117** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
4118** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
4119** is not a database file pathname pointer that the SQLite core passed
4120** into the xOpen VFS method, then the behavior of this routine is undefined
4121** and probably undesirable.
4122**
4123** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
4124** parameter can also be the name of a rollback journal file or WAL file
4125** in addition to the main database file. Prior to version 3.31.0, these
4126** routines would only work if F was the name of the main database file.
4127** When the F parameter is the name of the rollback journal or WAL file,
4128** it has access to all the same query parameters as were found on the
4129** main database file.
4130**
4131** See the [URI filename] documentation for additional information.
4132*/
4133SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam);
4134SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault);
4135SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64);
4136SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N);
4137
4138/*
4139** CAPI3REF: Translate filenames
4140**
4141** These routines are available to [VFS|custom VFS implementations] for
4142** translating filenames between the main database file, the journal file,
4143** and the WAL file.
4144**
4145** If F is the name of an sqlite database file, journal file, or WAL file
4146** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
4147** returns the name of the corresponding database file.
4148**
4149** If F is the name of an sqlite database file, journal file, or WAL file
4150** passed by the SQLite core into the VFS, or if F is a database filename
4151** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
4152** returns the name of the corresponding rollback journal file.
4153**
4154** If F is the name of an sqlite database file, journal file, or WAL file
4155** that was passed by the SQLite core into the VFS, or if F is a database
4156** filename obtained from [sqlite3_db_filename()], then
4157** sqlite3_filename_wal(F) returns the name of the corresponding
4158** WAL file.
4159**
4160** In all of the above, if F is not the name of a database, journal or WAL
4161** filename passed into the VFS from the SQLite core and F is not the
4162** return value from [sqlite3_db_filename()], then the result is
4163** undefined and is likely a memory access violation.
4164*/
4165SQLITE_API const char *sqlite3_filename_database(sqlite3_filename);
4166SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename);
4167SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename);
4168
4169/*
4170** CAPI3REF: Database File Corresponding To A Journal
4171**
4172** ^If X is the name of a rollback or WAL-mode journal file that is
4173** passed into the xOpen method of [sqlite3_vfs], then
4174** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
4175** object that represents the main database file.
4176**
4177** This routine is intended for use in custom [VFS] implementations
4178** only. It is not a general-purpose interface.
4179** The argument sqlite3_file_object(X) must be a filename pointer that
4180** has been passed into [sqlite3_vfs].xOpen method where the
4181** flags parameter to xOpen contains one of the bits
4182** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use
4183** of this routine results in undefined and probably undesirable
4184** behavior.
4185*/
4186SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
4187
4188/*
4189** CAPI3REF: Create and Destroy VFS Filenames
4190**
4191** These interfaces are provided for use by [VFS shim] implementations and
4192** are not useful outside of that context.
4193**
4194** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
4195** database filename D with corresponding journal file J and WAL file W and
4196** with N URI parameters key/values pairs in the array P. The result from
4197** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
4198** is safe to pass to routines like:
4199** <ul>
4200** <li> [sqlite3_uri_parameter()],
4201** <li> [sqlite3_uri_boolean()],
4202** <li> [sqlite3_uri_int64()],
4203** <li> [sqlite3_uri_key()],
4204** <li> [sqlite3_filename_database()],
4205** <li> [sqlite3_filename_journal()], or
4206** <li> [sqlite3_filename_wal()].
4207** </ul>
4208** If a memory allocation error occurs, sqlite3_create_filename() might
4209** return a NULL pointer. The memory obtained from sqlite3_create_filename(X)
4210** must be released by a corresponding call to sqlite3_free_filename(Y).
4211**
4212** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
4213** of 2*N pointers to strings. Each pair of pointers in this array corresponds
4214** to a key and value for a query parameter. The P parameter may be a NULL
4215** pointer if N is zero. None of the 2*N pointers in the P array may be
4216** NULL pointers and key pointers should not be empty strings.
4217** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
4218** be NULL pointers, though they can be empty strings.
4219**
4220** The sqlite3_free_filename(Y) routine releases a memory allocation
4221** previously obtained from sqlite3_create_filename(). Invoking
4222** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
4223**
4224** If the Y parameter to sqlite3_free_filename(Y) is anything other
4225** than a NULL pointer or a pointer previously acquired from
4226** sqlite3_create_filename(), then bad things such as heap
4227** corruption or segfaults may occur. The value Y should not be
4228** used again after sqlite3_free_filename(Y) has been called. This means
4229** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
4230** then the corresponding [sqlite3_module.xClose() method should also be
4231** invoked prior to calling sqlite3_free_filename(Y).
4232*/
4233SQLITE_API sqlite3_filename sqlite3_create_filename(
4234 const char *zDatabase,
4235 const char *zJournal,
4236 const char *zWal,
4237 int nParam,
4238 const char **azParam
4239);
4240SQLITE_API void sqlite3_free_filename(sqlite3_filename);
4241
4242/*
4243** CAPI3REF: Error Codes And Messages
4244** METHOD: sqlite3
4245**
4246** ^If the most recent sqlite3_* API call associated with
4247** [database connection] D failed, then the sqlite3_errcode(D) interface
4248** returns the numeric [result code] or [extended result code] for that
4249** API call.
4250** ^The sqlite3_extended_errcode()
4251** interface is the same except that it always returns the
4252** [extended result code] even when extended result codes are
4253** disabled.
4254**
4255** The values returned by sqlite3_errcode() and/or
4256** sqlite3_extended_errcode() might change with each API call.
4257** Except, there are some interfaces that are guaranteed to never
4258** change the value of the error code. The error-code preserving
4259** interfaces include the following:
4260**
4261** <ul>
4262** <li> sqlite3_errcode()
4263** <li> sqlite3_extended_errcode()
4264** <li> sqlite3_errmsg()
4265** <li> sqlite3_errmsg16()
4266** <li> sqlite3_error_offset()
4267** </ul>
4268**
4269** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
4270** text that describes the error, as either UTF-8 or UTF-16 respectively.
4271** ^(Memory to hold the error message string is managed internally.
4272** The application does not need to worry about freeing the result.
4273** However, the error string might be overwritten or deallocated by
4274** subsequent calls to other SQLite interface functions.)^
4275**
4276** ^The sqlite3_errstr() interface returns the English-language text
4277** that describes the [result code], as UTF-8.
4278** ^(Memory to hold the error message string is managed internally
4279** and must not be freed by the application)^.
4280**
4281** ^If the most recent error references a specific token in the input
4282** SQL, the sqlite3_error_offset() interface returns the byte offset
4283** of the start of that token. ^The byte offset returned by
4284** sqlite3_error_offset() assumes that the input SQL is UTF8.
4285** ^If the most recent error does not reference a specific token in the input
4286** SQL, then the sqlite3_error_offset() function returns -1.
4287**
4288** When the serialized [threading mode] is in use, it might be the
4289** case that a second error occurs on a separate thread in between
4290** the time of the first error and the call to these interfaces.
4291** When that happens, the second error will be reported since these
4292** interfaces always report the most recent result. To avoid
4293** this, each thread can obtain exclusive use of the [database connection] D
4294** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
4295** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
4296** all calls to the interfaces listed here are completed.
4297**
4298** If an interface fails with SQLITE_MISUSE, that means the interface
4299** was invoked incorrectly by the application. In that case, the
4300** error code and message may or may not be set.
4301*/
4302SQLITE_API int sqlite3_errcode(sqlite3 *db);
4303SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
4304SQLITE_API const char *sqlite3_errmsg(sqlite3*);
4305SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
4306SQLITE_API const char *sqlite3_errstr(int);
4307SQLITE_API int sqlite3_error_offset(sqlite3 *db);
4308
4309/*
4310** CAPI3REF: Prepared Statement Object
4311** KEYWORDS: {prepared statement} {prepared statements}
4312**
4313** An instance of this object represents a single SQL statement that
4314** has been compiled into binary form and is ready to be evaluated.
4315**
4316** Think of each SQL statement as a separate computer program. The
4317** original SQL text is source code. A prepared statement object
4318** is the compiled object code. All SQL must be converted into a
4319** prepared statement before it can be run.
4320**
4321** The life-cycle of a prepared statement object usually goes like this:
4322**
4323** <ol>
4324** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
4325** <li> Bind values to [parameters] using the sqlite3_bind_*()
4326** interfaces.
4327** <li> Run the SQL by calling [sqlite3_step()] one or more times.
4328** <li> Reset the prepared statement using [sqlite3_reset()] then go back
4329** to step 2. Do this zero or more times.
4330** <li> Destroy the object using [sqlite3_finalize()].
4331** </ol>
4332*/
4333typedef struct sqlite3_stmt sqlite3_stmt;
4334
4335/*
4336** CAPI3REF: Run-time Limits
4337** METHOD: sqlite3
4338**
4339** ^(This interface allows the size of various constructs to be limited
4340** on a connection by connection basis. The first parameter is the
4341** [database connection] whose limit is to be set or queried. The
4342** second parameter is one of the [limit categories] that define a
4343** class of constructs to be size limited. The third parameter is the
4344** new limit for that construct.)^
4345**
4346** ^If the new limit is a negative number, the limit is unchanged.
4347** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
4348** [limits | hard upper bound]
4349** set at compile-time by a C preprocessor macro called
4350** [limits | SQLITE_MAX_<i>NAME</i>].
4351** (The "_LIMIT_" in the name is changed to "_MAX_".))^
4352** ^Attempts to increase a limit above its hard upper bound are
4353** silently truncated to the hard upper bound.
4354**
4355** ^Regardless of whether or not the limit was changed, the
4356** [sqlite3_limit()] interface returns the prior value of the limit.
4357** ^Hence, to find the current value of a limit without changing it,
4358** simply invoke this interface with the third parameter set to -1.
4359**
4360** Run-time limits are intended for use in applications that manage
4361** both their own internal database and also databases that are controlled
4362** by untrusted external sources. An example application might be a
4363** web browser that has its own databases for storing history and
4364** separate databases controlled by JavaScript applications downloaded
4365** off the Internet. The internal databases can be given the
4366** large, default limits. Databases managed by external sources can
4367** be given much smaller limits designed to prevent a denial of service
4368** attack. Developers might also want to use the [sqlite3_set_authorizer()]
4369** interface to further control untrusted SQL. The size of the database
4370** created by an untrusted script can be contained using the
4371** [max_page_count] [PRAGMA].
4372**
4373** New run-time limit categories may be added in future releases.
4374*/
4375SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
4376
4377/*
4378** CAPI3REF: Run-Time Limit Categories
4379** KEYWORDS: {limit category} {*limit categories}
4380**
4381** These constants define various performance limits
4382** that can be lowered at run-time using [sqlite3_limit()].
4383** The synopsis of the meanings of the various limits is shown below.
4384** Additional information is available at [limits | Limits in SQLite].
4385**
4386** <dl>
4387** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
4388** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
4389**
4390** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
4391** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
4392**
4393** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
4394** <dd>The maximum number of columns in a table definition or in the
4395** result set of a [SELECT] or the maximum number of columns in an index
4396** or in an ORDER BY or GROUP BY clause.</dd>)^
4397**
4398** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
4399** <dd>The maximum depth of the parse tree on any expression.</dd>)^
4400**
4401** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
4402** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
4403**
4404** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
4405** <dd>The maximum number of instructions in a virtual machine program
4406** used to implement an SQL statement. If [sqlite3_prepare_v2()] or
4407** the equivalent tries to allocate space for more than this many opcodes
4408** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
4409**
4410** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
4411** <dd>The maximum number of arguments on a function.</dd>)^
4412**
4413** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
4414** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
4415**
4416** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
4417** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
4418** <dd>The maximum length of the pattern argument to the [LIKE] or
4419** [GLOB] operators.</dd>)^
4420**
4421** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
4422** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
4423** <dd>The maximum index number of any [parameter] in an SQL statement.)^
4424**
4425** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
4426** <dd>The maximum depth of recursion for triggers.</dd>)^
4427**
4428** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
4429** <dd>The maximum number of auxiliary worker threads that a single
4430** [prepared statement] may start.</dd>)^
4431** </dl>
4432*/
4433#define SQLITE_LIMIT_LENGTH 0
4434#define SQLITE_LIMIT_SQL_LENGTH 1
4435#define SQLITE_LIMIT_COLUMN 2
4436#define SQLITE_LIMIT_EXPR_DEPTH 3
4437#define SQLITE_LIMIT_COMPOUND_SELECT 4
4438#define SQLITE_LIMIT_VDBE_OP 5
4439#define SQLITE_LIMIT_FUNCTION_ARG 6
4440#define SQLITE_LIMIT_ATTACHED 7
4441#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
4442#define SQLITE_LIMIT_VARIABLE_NUMBER 9
4443#define SQLITE_LIMIT_TRIGGER_DEPTH 10
4444#define SQLITE_LIMIT_WORKER_THREADS 11
4445
4446/*
4447** CAPI3REF: Prepare Flags
4448**
4449** These constants define various flags that can be passed into
4450** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
4451** [sqlite3_prepare16_v3()] interfaces.
4452**
4453** New flags may be added in future releases of SQLite.
4454**
4455** <dl>
4456** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
4457** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
4458** that the prepared statement will be retained for a long time and
4459** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
4460** and [sqlite3_prepare16_v3()] assume that the prepared statement will
4461** be used just once or at most a few times and then destroyed using
4462** [sqlite3_finalize()] relatively soon. The current implementation acts
4463** on this hint by avoiding the use of [lookaside memory] so as not to
4464** deplete the limited store of lookaside memory. Future versions of
4465** SQLite may act on this hint differently.
4466**
4467** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
4468** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
4469** to be required for any prepared statement that wanted to use the
4470** [sqlite3_normalized_sql()] interface. However, the
4471** [sqlite3_normalized_sql()] interface is now available to all
4472** prepared statements, regardless of whether or not they use this
4473** flag.
4474**
4475** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
4476** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
4477** to return an error (error code SQLITE_ERROR) if the statement uses
4478** any virtual tables.
4479** </dl>
4480*/
4481#define SQLITE_PREPARE_PERSISTENT 0x01
4482#define SQLITE_PREPARE_NORMALIZE 0x02
4483#define SQLITE_PREPARE_NO_VTAB 0x04
4484
4485/*
4486** CAPI3REF: Compiling An SQL Statement
4487** KEYWORDS: {SQL statement compiler}
4488** METHOD: sqlite3
4489** CONSTRUCTOR: sqlite3_stmt
4490**
4491** To execute an SQL statement, it must first be compiled into a byte-code
4492** program using one of these routines. Or, in other words, these routines
4493** are constructors for the [prepared statement] object.
4494**
4495** The preferred routine to use is [sqlite3_prepare_v2()]. The
4496** [sqlite3_prepare()] interface is legacy and should be avoided.
4497** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
4498** for special purposes.
4499**
4500** The use of the UTF-8 interfaces is preferred, as SQLite currently
4501** does all parsing using UTF-8. The UTF-16 interfaces are provided
4502** as a convenience. The UTF-16 interfaces work by converting the
4503** input text into UTF-8, then invoking the corresponding UTF-8 interface.
4504**
4505** The first argument, "db", is a [database connection] obtained from a
4506** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
4507** [sqlite3_open16()]. The database connection must not have been closed.
4508**
4509** The second argument, "zSql", is the statement to be compiled, encoded
4510** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(),
4511** and sqlite3_prepare_v3()
4512** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
4513** and sqlite3_prepare16_v3() use UTF-16.
4514**
4515** ^If the nByte argument is negative, then zSql is read up to the
4516** first zero terminator. ^If nByte is positive, then it is the
4517** number of bytes read from zSql. ^If nByte is zero, then no prepared
4518** statement is generated.
4519** If the caller knows that the supplied string is nul-terminated, then
4520** there is a small performance advantage to passing an nByte parameter that
4521** is the number of bytes in the input string <i>including</i>
4522** the nul-terminator.
4523**
4524** ^If pzTail is not NULL then *pzTail is made to point to the first byte
4525** past the end of the first SQL statement in zSql. These routines only
4526** compile the first statement in zSql, so *pzTail is left pointing to
4527** what remains uncompiled.
4528**
4529** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
4530** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
4531** to NULL. ^If the input text contains no SQL (if the input is an empty
4532** string or a comment) then *ppStmt is set to NULL.
4533** The calling procedure is responsible for deleting the compiled
4534** SQL statement using [sqlite3_finalize()] after it has finished with it.
4535** ppStmt may not be NULL.
4536**
4537** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
4538** otherwise an [error code] is returned.
4539**
4540** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
4541** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
4542** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
4543** are retained for backwards compatibility, but their use is discouraged.
4544** ^In the "vX" interfaces, the prepared statement
4545** that is returned (the [sqlite3_stmt] object) contains a copy of the
4546** original SQL text. This causes the [sqlite3_step()] interface to
4547** behave differently in three ways:
4548**
4549** <ol>
4550** <li>
4551** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
4552** always used to do, [sqlite3_step()] will automatically recompile the SQL
4553** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
4554** retries will occur before sqlite3_step() gives up and returns an error.
4555** </li>
4556**
4557** <li>
4558** ^When an error occurs, [sqlite3_step()] will return one of the detailed
4559** [error codes] or [extended error codes]. ^The legacy behavior was that
4560** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
4561** and the application would have to make a second call to [sqlite3_reset()]
4562** in order to find the underlying cause of the problem. With the "v2" prepare
4563** interfaces, the underlying reason for the error is returned immediately.
4564** </li>
4565**
4566** <li>
4567** ^If the specific value bound to a [parameter | host parameter] in the
4568** WHERE clause might influence the choice of query plan for a statement,
4569** then the statement will be automatically recompiled, as if there had been
4570** a schema change, on the first [sqlite3_step()] call following any change
4571** to the [sqlite3_bind_text | bindings] of that [parameter].
4572** ^The specific value of a WHERE-clause [parameter] might influence the
4573** choice of query plan if the parameter is the left-hand side of a [LIKE]
4574** or [GLOB] operator or if the parameter is compared to an indexed column
4575** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
4576** </li>
4577** </ol>
4578**
4579** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
4580** the extra prepFlags parameter, which is a bit array consisting of zero or
4581** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The
4582** sqlite3_prepare_v2() interface works exactly the same as
4583** sqlite3_prepare_v3() with a zero prepFlags parameter.
4584*/
4585SQLITE_API int sqlite3_prepare(
4586 sqlite3 *db, /* Database handle */
4587 const char *zSql, /* SQL statement, UTF-8 encoded */
4588 int nByte, /* Maximum length of zSql in bytes. */
4589 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4590 const char **pzTail /* OUT: Pointer to unused portion of zSql */
4591);
4592SQLITE_API int sqlite3_prepare_v2(
4593 sqlite3 *db, /* Database handle */
4594 const char *zSql, /* SQL statement, UTF-8 encoded */
4595 int nByte, /* Maximum length of zSql in bytes. */
4596 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4597 const char **pzTail /* OUT: Pointer to unused portion of zSql */
4598);
4599SQLITE_API int sqlite3_prepare_v3(
4600 sqlite3 *db, /* Database handle */
4601 const char *zSql, /* SQL statement, UTF-8 encoded */
4602 int nByte, /* Maximum length of zSql in bytes. */
4603 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4604 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4605 const char **pzTail /* OUT: Pointer to unused portion of zSql */
4606);
4607SQLITE_API int sqlite3_prepare16(
4608 sqlite3 *db, /* Database handle */
4609 const void *zSql, /* SQL statement, UTF-16 encoded */
4610 int nByte, /* Maximum length of zSql in bytes. */
4611 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4612 const void **pzTail /* OUT: Pointer to unused portion of zSql */
4613);
4614SQLITE_API int sqlite3_prepare16_v2(
4615 sqlite3 *db, /* Database handle */
4616 const void *zSql, /* SQL statement, UTF-16 encoded */
4617 int nByte, /* Maximum length of zSql in bytes. */
4618 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4619 const void **pzTail /* OUT: Pointer to unused portion of zSql */
4620);
4621SQLITE_API int sqlite3_prepare16_v3(
4622 sqlite3 *db, /* Database handle */
4623 const void *zSql, /* SQL statement, UTF-16 encoded */
4624 int nByte, /* Maximum length of zSql in bytes. */
4625 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4626 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4627 const void **pzTail /* OUT: Pointer to unused portion of zSql */
4628);
4629
4630/*
4631** CAPI3REF: Retrieving Statement SQL
4632** METHOD: sqlite3_stmt
4633**
4634** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
4635** SQL text used to create [prepared statement] P if P was
4636** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
4637** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4638** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
4639** string containing the SQL text of prepared statement P with
4640** [bound parameters] expanded.
4641** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
4642** string containing the normalized SQL text of prepared statement P. The
4643** semantics used to normalize a SQL statement are unspecified and subject
4644** to change. At a minimum, literal values will be replaced with suitable
4645** placeholders.
4646**
4647** ^(For example, if a prepared statement is created using the SQL
4648** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
4649** and parameter :xyz is unbound, then sqlite3_sql() will return
4650** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
4651** will return "SELECT 2345,NULL".)^
4652**
4653** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
4654** is available to hold the result, or if the result would exceed the
4655** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
4656**
4657** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
4658** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time
4659** option causes sqlite3_expanded_sql() to always return NULL.
4660**
4661** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
4662** are managed by SQLite and are automatically freed when the prepared
4663** statement is finalized.
4664** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
4665** is obtained from [sqlite3_malloc()] and must be freed by the application
4666** by passing it to [sqlite3_free()].
4667**
4668** ^The sqlite3_normalized_sql() interface is only available if
4669** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined.
4670*/
4671SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
4672SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
4673#ifdef SQLITE_ENABLE_NORMALIZE
4674SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
4675#endif
4676
4677/*
4678** CAPI3REF: Determine If An SQL Statement Writes The Database
4679** METHOD: sqlite3_stmt
4680**
4681** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
4682** and only if the [prepared statement] X makes no direct changes to
4683** the content of the database file.
4684**
4685** Note that [application-defined SQL functions] or
4686** [virtual tables] might change the database indirectly as a side effect.
4687** ^(For example, if an application defines a function "eval()" that
4688** calls [sqlite3_exec()], then the following SQL statement would
4689** change the database file through side-effects:
4690**
4691** <blockquote><pre>
4692** SELECT eval('DELETE FROM t1') FROM t2;
4693** </pre></blockquote>
4694**
4695** But because the [SELECT] statement does not change the database file
4696** directly, sqlite3_stmt_readonly() would still return true.)^
4697**
4698** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
4699** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
4700** since the statements themselves do not actually modify the database but
4701** rather they control the timing of when other statements modify the
4702** database. ^The [ATTACH] and [DETACH] statements also cause
4703** sqlite3_stmt_readonly() to return true since, while those statements
4704** change the configuration of a database connection, they do not make
4705** changes to the content of the database files on disk.
4706** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
4707** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
4708** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
4709** sqlite3_stmt_readonly() returns false for those commands.
4710**
4711** ^This routine returns false if there is any possibility that the
4712** statement might change the database file. ^A false return does
4713** not guarantee that the statement will change the database file.
4714** ^For example, an UPDATE statement might have a WHERE clause that
4715** makes it a no-op, but the sqlite3_stmt_readonly() result would still
4716** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a
4717** read-only no-op if the table already exists, but
4718** sqlite3_stmt_readonly() still returns false for such a statement.
4719**
4720** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN]
4721** statement, then sqlite3_stmt_readonly(X) returns the same value as
4722** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted.
4723*/
4724SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
4725
4726/*
4727** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
4728** METHOD: sqlite3_stmt
4729**
4730** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
4731** prepared statement S is an EXPLAIN statement, or 2 if the
4732** statement S is an EXPLAIN QUERY PLAN.
4733** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
4734** an ordinary statement or a NULL pointer.
4735*/
4736SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
4737
4738/*
4739** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement
4740** METHOD: sqlite3_stmt
4741**
4742** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN
4743** setting for [prepared statement] S. If E is zero, then S becomes
4744** a normal prepared statement. If E is 1, then S behaves as if
4745** its SQL text began with "[EXPLAIN]". If E is 2, then S behaves as if
4746** its SQL text began with "[EXPLAIN QUERY PLAN]".
4747**
4748** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared.
4749** SQLite tries to avoid a reprepare, but a reprepare might be necessary
4750** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode.
4751**
4752** Because of the potential need to reprepare, a call to
4753** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be
4754** reprepared because it was created using [sqlite3_prepare()] instead of
4755** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and
4756** hence has no saved SQL text with which to reprepare.
4757**
4758** Changing the explain setting for a prepared statement does not change
4759** the original SQL text for the statement. Hence, if the SQL text originally
4760** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0)
4761** is called to convert the statement into an ordinary statement, the EXPLAIN
4762** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S)
4763** output, even though the statement now acts like a normal SQL statement.
4764**
4765** This routine returns SQLITE_OK if the explain mode is successfully
4766** changed, or an error code if the explain mode could not be changed.
4767** The explain mode cannot be changed while a statement is active.
4768** Hence, it is good practice to call [sqlite3_reset(S)]
4769** immediately prior to calling sqlite3_stmt_explain(S,E).
4770*/
4771SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode);
4772
4773/*
4774** CAPI3REF: Determine If A Prepared Statement Has Been Reset
4775** METHOD: sqlite3_stmt
4776**
4777** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
4778** [prepared statement] S has been stepped at least once using
4779** [sqlite3_step(S)] but has neither run to completion (returned
4780** [SQLITE_DONE] from [sqlite3_step(S)]) nor
4781** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
4782** interface returns false if S is a NULL pointer. If S is not a
4783** NULL pointer and is not a pointer to a valid [prepared statement]
4784** object, then the behavior is undefined and probably undesirable.
4785**
4786** This interface can be used in combination [sqlite3_next_stmt()]
4787** to locate all prepared statements associated with a database
4788** connection that are in need of being reset. This can be used,
4789** for example, in diagnostic routines to search for prepared
4790** statements that are holding a transaction open.
4791*/
4792SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
4793
4794/*
4795** CAPI3REF: Dynamically Typed Value Object
4796** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
4797**
4798** SQLite uses the sqlite3_value object to represent all values
4799** that can be stored in a database table. SQLite uses dynamic typing
4800** for the values it stores. ^Values stored in sqlite3_value objects
4801** can be integers, floating point values, strings, BLOBs, or NULL.
4802**
4803** An sqlite3_value object may be either "protected" or "unprotected".
4804** Some interfaces require a protected sqlite3_value. Other interfaces
4805** will accept either a protected or an unprotected sqlite3_value.
4806** Every interface that accepts sqlite3_value arguments specifies
4807** whether or not it requires a protected sqlite3_value. The
4808** [sqlite3_value_dup()] interface can be used to construct a new
4809** protected sqlite3_value from an unprotected sqlite3_value.
4810**
4811** The terms "protected" and "unprotected" refer to whether or not
4812** a mutex is held. An internal mutex is held for a protected
4813** sqlite3_value object but no mutex is held for an unprotected
4814** sqlite3_value object. If SQLite is compiled to be single-threaded
4815** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
4816** or if SQLite is run in one of reduced mutex modes
4817** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
4818** then there is no distinction between protected and unprotected
4819** sqlite3_value objects and they can be used interchangeably. However,
4820** for maximum code portability it is recommended that applications
4821** still make the distinction between protected and unprotected
4822** sqlite3_value objects even when not strictly required.
4823**
4824** ^The sqlite3_value objects that are passed as parameters into the
4825** implementation of [application-defined SQL functions] are protected.
4826** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()]
4827** are protected.
4828** ^The sqlite3_value object returned by
4829** [sqlite3_column_value()] is unprotected.
4830** Unprotected sqlite3_value objects may only be used as arguments
4831** to [sqlite3_result_value()], [sqlite3_bind_value()], and
4832** [sqlite3_value_dup()].
4833** The [sqlite3_value_blob | sqlite3_value_type()] family of
4834** interfaces require protected sqlite3_value objects.
4835*/
4836typedef struct sqlite3_value sqlite3_value;
4837
4838/*
4839** CAPI3REF: SQL Function Context Object
4840**
4841** The context in which an SQL function executes is stored in an
4842** sqlite3_context object. ^A pointer to an sqlite3_context object
4843** is always first parameter to [application-defined SQL functions].
4844** The application-defined SQL function implementation will pass this
4845** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
4846** [sqlite3_aggregate_context()], [sqlite3_user_data()],
4847** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
4848** and/or [sqlite3_set_auxdata()].
4849*/
4850typedef struct sqlite3_context sqlite3_context;
4851
4852/*
4853** CAPI3REF: Binding Values To Prepared Statements
4854** KEYWORDS: {host parameter} {host parameters} {host parameter name}
4855** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
4856** METHOD: sqlite3_stmt
4857**
4858** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
4859** literals may be replaced by a [parameter] that matches one of following
4860** templates:
4861**
4862** <ul>
4863** <li> ?
4864** <li> ?NNN
4865** <li> :VVV
4866** <li> @VVV
4867** <li> $VVV
4868** </ul>
4869**
4870** In the templates above, NNN represents an integer literal,
4871** and VVV represents an alphanumeric identifier.)^ ^The values of these
4872** parameters (also called "host parameter names" or "SQL parameters")
4873** can be set using the sqlite3_bind_*() routines defined here.
4874**
4875** ^The first argument to the sqlite3_bind_*() routines is always
4876** a pointer to the [sqlite3_stmt] object returned from
4877** [sqlite3_prepare_v2()] or its variants.
4878**
4879** ^The second argument is the index of the SQL parameter to be set.
4880** ^The leftmost SQL parameter has an index of 1. ^When the same named
4881** SQL parameter is used more than once, second and subsequent
4882** occurrences have the same index as the first occurrence.
4883** ^The index for named parameters can be looked up using the
4884** [sqlite3_bind_parameter_index()] API if desired. ^The index
4885** for "?NNN" parameters is the value of NNN.
4886** ^The NNN value must be between 1 and the [sqlite3_limit()]
4887** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
4888**
4889** ^The third argument is the value to bind to the parameter.
4890** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4891** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
4892** is ignored and the end result is the same as sqlite3_bind_null().
4893** ^If the third parameter to sqlite3_bind_text() is not NULL, then
4894** it should be a pointer to well-formed UTF8 text.
4895** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
4896** it should be a pointer to well-formed UTF16 text.
4897** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
4898** it should be a pointer to a well-formed unicode string that is
4899** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16
4900** otherwise.
4901**
4902** [[byte-order determination rules]] ^The byte-order of
4903** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
4904** found in first character, which is removed, or in the absence of a BOM
4905** the byte order is the native byte order of the host
4906** machine for sqlite3_bind_text16() or the byte order specified in
4907** the 6th parameter for sqlite3_bind_text64().)^
4908** ^If UTF16 input text contains invalid unicode
4909** characters, then SQLite might change those invalid characters
4910** into the unicode replacement character: U+FFFD.
4911**
4912** ^(In those routines that have a fourth argument, its value is the
4913** number of bytes in the parameter. To be clear: the value is the
4914** number of <u>bytes</u> in the value, not the number of characters.)^
4915** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4916** is negative, then the length of the string is
4917** the number of bytes up to the first zero terminator.
4918** If the fourth parameter to sqlite3_bind_blob() is negative, then
4919** the behavior is undefined.
4920** If a non-negative fourth parameter is provided to sqlite3_bind_text()
4921** or sqlite3_bind_text16() or sqlite3_bind_text64() then
4922** that parameter must be the byte offset
4923** where the NUL terminator would occur assuming the string were NUL
4924** terminated. If any NUL characters occurs at byte offsets less than
4925** the value of the fourth parameter then the resulting string value will
4926** contain embedded NULs. The result of expressions involving strings
4927** with embedded NULs is undefined.
4928**
4929** ^The fifth argument to the BLOB and string binding interfaces controls
4930** or indicates the lifetime of the object referenced by the third parameter.
4931** These three options exist:
4932** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished
4933** with it may be passed. ^It is called to dispose of the BLOB or string even
4934** if the call to the bind API fails, except the destructor is not called if
4935** the third parameter is a NULL pointer or the fourth parameter is negative.
4936** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that
4937** the application remains responsible for disposing of the object. ^In this
4938** case, the object and the provided pointer to it must remain valid until
4939** either the prepared statement is finalized or the same SQL parameter is
4940** bound to something else, whichever occurs sooner.
4941** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the
4942** object is to be copied prior to the return from sqlite3_bind_*(). ^The
4943** object and pointer to it must remain valid until then. ^SQLite will then
4944** manage the lifetime of its private copy.
4945**
4946** ^The sixth argument to sqlite3_bind_text64() must be one of
4947** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
4948** to specify the encoding of the text in the third parameter. If
4949** the sixth argument to sqlite3_bind_text64() is not one of the
4950** allowed values shown above, or if the text encoding is different
4951** from the encoding specified by the sixth parameter, then the behavior
4952** is undefined.
4953**
4954** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
4955** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
4956** (just an integer to hold its size) while it is being processed.
4957** Zeroblobs are intended to serve as placeholders for BLOBs whose
4958** content is later written using
4959** [sqlite3_blob_open | incremental BLOB I/O] routines.
4960** ^A negative value for the zeroblob results in a zero-length BLOB.
4961**
4962** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
4963** [prepared statement] S to have an SQL value of NULL, but to also be
4964** associated with the pointer P of type T. ^D is either a NULL pointer or
4965** a pointer to a destructor function for P. ^SQLite will invoke the
4966** destructor D with a single argument of P when it is finished using
4967** P. The T parameter should be a static string, preferably a string
4968** literal. The sqlite3_bind_pointer() routine is part of the
4969** [pointer passing interface] added for SQLite 3.20.0.
4970**
4971** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
4972** for the [prepared statement] or with a prepared statement for which
4973** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
4974** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
4975** routine is passed a [prepared statement] that has been finalized, the
4976** result is undefined and probably harmful.
4977**
4978** ^Bindings are not cleared by the [sqlite3_reset()] routine.
4979** ^Unbound parameters are interpreted as NULL.
4980**
4981** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
4982** [error code] if anything goes wrong.
4983** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
4984** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
4985** [SQLITE_MAX_LENGTH].
4986** ^[SQLITE_RANGE] is returned if the parameter
4987** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
4988**
4989** See also: [sqlite3_bind_parameter_count()],
4990** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
4991*/
4992SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
4993SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
4994 void(*)(void*));
4995SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
4996SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
4997SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
4998SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
4999SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
5000SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
5001SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
5002 void(*)(void*), unsigned char encoding);
5003SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
5004SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
5005SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
5006SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
5007
5008/*
5009** CAPI3REF: Number Of SQL Parameters
5010** METHOD: sqlite3_stmt
5011**
5012** ^This routine can be used to find the number of [SQL parameters]
5013** in a [prepared statement]. SQL parameters are tokens of the
5014** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
5015** placeholders for values that are [sqlite3_bind_blob | bound]
5016** to the parameters at a later time.
5017**
5018** ^(This routine actually returns the index of the largest (rightmost)
5019** parameter. For all forms except ?NNN, this will correspond to the
5020** number of unique parameters. If parameters of the ?NNN form are used,
5021** there may be gaps in the list.)^
5022**
5023** See also: [sqlite3_bind_blob|sqlite3_bind()],
5024** [sqlite3_bind_parameter_name()], and
5025** [sqlite3_bind_parameter_index()].
5026*/
5027SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
5028
5029/*
5030** CAPI3REF: Name Of A Host Parameter
5031** METHOD: sqlite3_stmt
5032**
5033** ^The sqlite3_bind_parameter_name(P,N) interface returns
5034** the name of the N-th [SQL parameter] in the [prepared statement] P.
5035** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
5036** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
5037** respectively.
5038** In other words, the initial ":" or "$" or "@" or "?"
5039** is included as part of the name.)^
5040** ^Parameters of the form "?" without a following integer have no name
5041** and are referred to as "nameless" or "anonymous parameters".
5042**
5043** ^The first host parameter has an index of 1, not 0.
5044**
5045** ^If the value N is out of range or if the N-th parameter is
5046** nameless, then NULL is returned. ^The returned string is
5047** always in UTF-8 encoding even if the named parameter was
5048** originally specified as UTF-16 in [sqlite3_prepare16()],
5049** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
5050**
5051** See also: [sqlite3_bind_blob|sqlite3_bind()],
5052** [sqlite3_bind_parameter_count()], and
5053** [sqlite3_bind_parameter_index()].
5054*/
5055SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
5056
5057/*
5058** CAPI3REF: Index Of A Parameter With A Given Name
5059** METHOD: sqlite3_stmt
5060**
5061** ^Return the index of an SQL parameter given its name. ^The
5062** index value returned is suitable for use as the second
5063** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
5064** is returned if no matching parameter is found. ^The parameter
5065** name must be given in UTF-8 even if the original statement
5066** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
5067** [sqlite3_prepare16_v3()].
5068**
5069** See also: [sqlite3_bind_blob|sqlite3_bind()],
5070** [sqlite3_bind_parameter_count()], and
5071** [sqlite3_bind_parameter_name()].
5072*/
5073SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
5074
5075/*
5076** CAPI3REF: Reset All Bindings On A Prepared Statement
5077** METHOD: sqlite3_stmt
5078**
5079** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
5080** the [sqlite3_bind_blob | bindings] on a [prepared statement].
5081** ^Use this routine to reset all host parameters to NULL.
5082*/
5083SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
5084
5085/*
5086** CAPI3REF: Number Of Columns In A Result Set
5087** METHOD: sqlite3_stmt
5088**
5089** ^Return the number of columns in the result set returned by the
5090** [prepared statement]. ^If this routine returns 0, that means the
5091** [prepared statement] returns no data (for example an [UPDATE]).
5092** ^However, just because this routine returns a positive number does not
5093** mean that one or more rows of data will be returned. ^A SELECT statement
5094** will always have a positive sqlite3_column_count() but depending on the
5095** WHERE clause constraints and the table content, it might return no rows.
5096**
5097** See also: [sqlite3_data_count()]
5098*/
5099SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
5100
5101/*
5102** CAPI3REF: Column Names In A Result Set
5103** METHOD: sqlite3_stmt
5104**
5105** ^These routines return the name assigned to a particular column
5106** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
5107** interface returns a pointer to a zero-terminated UTF-8 string
5108** and sqlite3_column_name16() returns a pointer to a zero-terminated
5109** UTF-16 string. ^The first parameter is the [prepared statement]
5110** that implements the [SELECT] statement. ^The second parameter is the
5111** column number. ^The leftmost column is number 0.
5112**
5113** ^The returned string pointer is valid until either the [prepared statement]
5114** is destroyed by [sqlite3_finalize()] or until the statement is automatically
5115** reprepared by the first call to [sqlite3_step()] for a particular run
5116** or until the next call to
5117** sqlite3_column_name() or sqlite3_column_name16() on the same column.
5118**
5119** ^If sqlite3_malloc() fails during the processing of either routine
5120** (for example during a conversion from UTF-8 to UTF-16) then a
5121** NULL pointer is returned.
5122**
5123** ^The name of a result column is the value of the "AS" clause for
5124** that column, if there is an AS clause. If there is no AS clause
5125** then the name of the column is unspecified and may change from
5126** one release of SQLite to the next.
5127*/
5128SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
5129SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
5130
5131/*
5132** CAPI3REF: Source Of Data In A Query Result
5133** METHOD: sqlite3_stmt
5134**
5135** ^These routines provide a means to determine the database, table, and
5136** table column that is the origin of a particular result column in
5137** [SELECT] statement.
5138** ^The name of the database or table or column can be returned as
5139** either a UTF-8 or UTF-16 string. ^The _database_ routines return
5140** the database name, the _table_ routines return the table name, and
5141** the origin_ routines return the column name.
5142** ^The returned string is valid until the [prepared statement] is destroyed
5143** using [sqlite3_finalize()] or until the statement is automatically
5144** reprepared by the first call to [sqlite3_step()] for a particular run
5145** or until the same information is requested
5146** again in a different encoding.
5147**
5148** ^The names returned are the original un-aliased names of the
5149** database, table, and column.
5150**
5151** ^The first argument to these interfaces is a [prepared statement].
5152** ^These functions return information about the Nth result column returned by
5153** the statement, where N is the second function argument.
5154** ^The left-most column is column 0 for these routines.
5155**
5156** ^If the Nth column returned by the statement is an expression or
5157** subquery and is not a column value, then all of these functions return
5158** NULL. ^These routines might also return NULL if a memory allocation error
5159** occurs. ^Otherwise, they return the name of the attached database, table,
5160** or column that query result column was extracted from.
5161**
5162** ^As with all other SQLite APIs, those whose names end with "16" return
5163** UTF-16 encoded strings and the other functions return UTF-8.
5164**
5165** ^These APIs are only available if the library was compiled with the
5166** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
5167**
5168** If two or more threads call one or more
5169** [sqlite3_column_database_name | column metadata interfaces]
5170** for the same [prepared statement] and result column
5171** at the same time then the results are undefined.
5172*/
5173SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
5174SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
5175SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
5176SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
5177SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
5178SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
5179
5180/*
5181** CAPI3REF: Declared Datatype Of A Query Result
5182** METHOD: sqlite3_stmt
5183**
5184** ^(The first parameter is a [prepared statement].
5185** If this statement is a [SELECT] statement and the Nth column of the
5186** returned result set of that [SELECT] is a table column (not an
5187** expression or subquery) then the declared type of the table
5188** column is returned.)^ ^If the Nth column of the result set is an
5189** expression or subquery, then a NULL pointer is returned.
5190** ^The returned string is always UTF-8 encoded.
5191**
5192** ^(For example, given the database schema:
5193**
5194** CREATE TABLE t1(c1 VARIANT);
5195**
5196** and the following statement to be compiled:
5197**
5198** SELECT c1 + 1, c1 FROM t1;
5199**
5200** this routine would return the string "VARIANT" for the second result
5201** column (i==1), and a NULL pointer for the first result column (i==0).)^
5202**
5203** ^SQLite uses dynamic run-time typing. ^So just because a column
5204** is declared to contain a particular type does not mean that the
5205** data stored in that column is of the declared type. SQLite is
5206** strongly typed, but the typing is dynamic not static. ^Type
5207** is associated with individual values, not with the containers
5208** used to hold those values.
5209*/
5210SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
5211SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
5212
5213/*
5214** CAPI3REF: Evaluate An SQL Statement
5215** METHOD: sqlite3_stmt
5216**
5217** After a [prepared statement] has been prepared using any of
5218** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
5219** or [sqlite3_prepare16_v3()] or one of the legacy
5220** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
5221** must be called one or more times to evaluate the statement.
5222**
5223** The details of the behavior of the sqlite3_step() interface depend
5224** on whether the statement was prepared using the newer "vX" interfaces
5225** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
5226** [sqlite3_prepare16_v2()] or the older legacy
5227** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
5228** new "vX" interface is recommended for new applications but the legacy
5229** interface will continue to be supported.
5230**
5231** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
5232** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
5233** ^With the "v2" interface, any of the other [result codes] or
5234** [extended result codes] might be returned as well.
5235**
5236** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
5237** database locks it needs to do its job. ^If the statement is a [COMMIT]
5238** or occurs outside of an explicit transaction, then you can retry the
5239** statement. If the statement is not a [COMMIT] and occurs within an
5240** explicit transaction then you should rollback the transaction before
5241** continuing.
5242**
5243** ^[SQLITE_DONE] means that the statement has finished executing
5244** successfully. sqlite3_step() should not be called again on this virtual
5245** machine without first calling [sqlite3_reset()] to reset the virtual
5246** machine back to its initial state.
5247**
5248** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
5249** is returned each time a new row of data is ready for processing by the
5250** caller. The values may be accessed using the [column access functions].
5251** sqlite3_step() is called again to retrieve the next row of data.
5252**
5253** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
5254** violation) has occurred. sqlite3_step() should not be called again on
5255** the VM. More information may be found by calling [sqlite3_errmsg()].
5256** ^With the legacy interface, a more specific error code (for example,
5257** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
5258** can be obtained by calling [sqlite3_reset()] on the
5259** [prepared statement]. ^In the "v2" interface,
5260** the more specific error code is returned directly by sqlite3_step().
5261**
5262** [SQLITE_MISUSE] means that the this routine was called inappropriately.
5263** Perhaps it was called on a [prepared statement] that has
5264** already been [sqlite3_finalize | finalized] or on one that had
5265** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
5266** be the case that the same database connection is being used by two or
5267** more threads at the same moment in time.
5268**
5269** For all versions of SQLite up to and including 3.6.23.1, a call to
5270** [sqlite3_reset()] was required after sqlite3_step() returned anything
5271** other than [SQLITE_ROW] before any subsequent invocation of
5272** sqlite3_step(). Failure to reset the prepared statement using
5273** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
5274** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1],
5275** sqlite3_step() began
5276** calling [sqlite3_reset()] automatically in this circumstance rather
5277** than returning [SQLITE_MISUSE]. This is not considered a compatibility
5278** break because any application that ever receives an SQLITE_MISUSE error
5279** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
5280** can be used to restore the legacy behavior.
5281**
5282** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
5283** API always returns a generic error code, [SQLITE_ERROR], following any
5284** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
5285** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
5286** specific [error codes] that better describes the error.
5287** We admit that this is a goofy design. The problem has been fixed
5288** with the "v2" interface. If you prepare all of your SQL statements
5289** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
5290** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
5291** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
5292** then the more specific [error codes] are returned directly
5293** by sqlite3_step(). The use of the "vX" interfaces is recommended.
5294*/
5295SQLITE_API int sqlite3_step(sqlite3_stmt*);
5296
5297/*
5298** CAPI3REF: Number of columns in a result set
5299** METHOD: sqlite3_stmt
5300**
5301** ^The sqlite3_data_count(P) interface returns the number of columns in the
5302** current row of the result set of [prepared statement] P.
5303** ^If prepared statement P does not have results ready to return
5304** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
5305** interfaces) then sqlite3_data_count(P) returns 0.
5306** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
5307** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
5308** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
5309** will return non-zero if previous call to [sqlite3_step](P) returned
5310** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
5311** where it always returns zero since each step of that multi-step
5312** pragma returns 0 columns of data.
5313**
5314** See also: [sqlite3_column_count()]
5315*/
5316SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
5317
5318/*
5319** CAPI3REF: Fundamental Datatypes
5320** KEYWORDS: SQLITE_TEXT
5321**
5322** ^(Every value in SQLite has one of five fundamental datatypes:
5323**
5324** <ul>
5325** <li> 64-bit signed integer
5326** <li> 64-bit IEEE floating point number
5327** <li> string
5328** <li> BLOB
5329** <li> NULL
5330** </ul>)^
5331**
5332** These constants are codes for each of those types.
5333**
5334** Note that the SQLITE_TEXT constant was also used in SQLite version 2
5335** for a completely different meaning. Software that links against both
5336** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
5337** SQLITE_TEXT.
5338*/
5339#define SQLITE_INTEGER 1
5340#define SQLITE_FLOAT 2
5341#define SQLITE_BLOB 4
5342#define SQLITE_NULL 5
5343#ifdef SQLITE_TEXT
5344# undef SQLITE_TEXT
5345#else
5346# define SQLITE_TEXT 3
5347#endif
5348#define SQLITE3_TEXT 3
5349
5350/*
5351** CAPI3REF: Result Values From A Query
5352** KEYWORDS: {column access functions}
5353** METHOD: sqlite3_stmt
5354**
5355** <b>Summary:</b>
5356** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5357** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
5358** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
5359** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
5360** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
5361** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
5362** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
5363** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
5364** [sqlite3_value|unprotected sqlite3_value] object.
5365** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5366** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
5367** or a UTF-8 TEXT result in bytes
5368** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
5369** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5370** TEXT in bytes
5371** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
5372** datatype of the result
5373** </table></blockquote>
5374**
5375** <b>Details:</b>
5376**
5377** ^These routines return information about a single column of the current
5378** result row of a query. ^In every case the first argument is a pointer
5379** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
5380** that was returned from [sqlite3_prepare_v2()] or one of its variants)
5381** and the second argument is the index of the column for which information
5382** should be returned. ^The leftmost column of the result set has the index 0.
5383** ^The number of columns in the result can be determined using
5384** [sqlite3_column_count()].
5385**
5386** If the SQL statement does not currently point to a valid row, or if the
5387** column index is out of range, the result is undefined.
5388** These routines may only be called when the most recent call to
5389** [sqlite3_step()] has returned [SQLITE_ROW] and neither
5390** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
5391** If any of these routines are called after [sqlite3_reset()] or
5392** [sqlite3_finalize()] or after [sqlite3_step()] has returned
5393** something other than [SQLITE_ROW], the results are undefined.
5394** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
5395** are called from a different thread while any of these routines
5396** are pending, then the results are undefined.
5397**
5398** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
5399** each return the value of a result column in a specific data format. If
5400** the result column is not initially in the requested format (for example,
5401** if the query returns an integer but the sqlite3_column_text() interface
5402** is used to extract the value) then an automatic type conversion is performed.
5403**
5404** ^The sqlite3_column_type() routine returns the
5405** [SQLITE_INTEGER | datatype code] for the initial data type
5406** of the result column. ^The returned value is one of [SQLITE_INTEGER],
5407** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
5408** The return value of sqlite3_column_type() can be used to decide which
5409** of the first six interface should be used to extract the column value.
5410** The value returned by sqlite3_column_type() is only meaningful if no
5411** automatic type conversions have occurred for the value in question.
5412** After a type conversion, the result of calling sqlite3_column_type()
5413** is undefined, though harmless. Future
5414** versions of SQLite may change the behavior of sqlite3_column_type()
5415** following a type conversion.
5416**
5417** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
5418** or sqlite3_column_bytes16() interfaces can be used to determine the size
5419** of that BLOB or string.
5420**
5421** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
5422** routine returns the number of bytes in that BLOB or string.
5423** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
5424** the string to UTF-8 and then returns the number of bytes.
5425** ^If the result is a numeric value then sqlite3_column_bytes() uses
5426** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
5427** the number of bytes in that string.
5428** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
5429**
5430** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
5431** routine returns the number of bytes in that BLOB or string.
5432** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
5433** the string to UTF-16 and then returns the number of bytes.
5434** ^If the result is a numeric value then sqlite3_column_bytes16() uses
5435** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
5436** the number of bytes in that string.
5437** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
5438**
5439** ^The values returned by [sqlite3_column_bytes()] and
5440** [sqlite3_column_bytes16()] do not include the zero terminators at the end
5441** of the string. ^For clarity: the values returned by
5442** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
5443** bytes in the string, not the number of characters.
5444**
5445** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
5446** even empty strings, are always zero-terminated. ^The return
5447** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
5448**
5449** ^Strings returned by sqlite3_column_text16() always have the endianness
5450** which is native to the platform, regardless of the text encoding set
5451** for the database.
5452**
5453** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
5454** [unprotected sqlite3_value] object. In a multithreaded environment,
5455** an unprotected sqlite3_value object may only be used safely with
5456** [sqlite3_bind_value()] and [sqlite3_result_value()].
5457** If the [unprotected sqlite3_value] object returned by
5458** [sqlite3_column_value()] is used in any other way, including calls
5459** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
5460** or [sqlite3_value_bytes()], the behavior is not threadsafe.
5461** Hence, the sqlite3_column_value() interface
5462** is normally only useful within the implementation of
5463** [application-defined SQL functions] or [virtual tables], not within
5464** top-level application code.
5465**
5466** These routines may attempt to convert the datatype of the result.
5467** ^For example, if the internal representation is FLOAT and a text result
5468** is requested, [sqlite3_snprintf()] is used internally to perform the
5469** conversion automatically. ^(The following table details the conversions
5470** that are applied:
5471**
5472** <blockquote>
5473** <table border="1">
5474** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
5475**
5476** <tr><td> NULL <td> INTEGER <td> Result is 0
5477** <tr><td> NULL <td> FLOAT <td> Result is 0.0
5478** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer
5479** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer
5480** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
5481** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
5482** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
5483** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER
5484** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
5485** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB
5486** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER
5487** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL
5488** <tr><td> TEXT <td> BLOB <td> No change
5489** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER
5490** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL
5491** <tr><td> BLOB <td> TEXT <td> [CAST] to TEXT, ensure zero terminator
5492** </table>
5493** </blockquote>)^
5494**
5495** Note that when type conversions occur, pointers returned by prior
5496** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
5497** sqlite3_column_text16() may be invalidated.
5498** Type conversions and pointer invalidations might occur
5499** in the following cases:
5500**
5501** <ul>
5502** <li> The initial content is a BLOB and sqlite3_column_text() or
5503** sqlite3_column_text16() is called. A zero-terminator might
5504** need to be added to the string.</li>
5505** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
5506** sqlite3_column_text16() is called. The content must be converted
5507** to UTF-16.</li>
5508** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
5509** sqlite3_column_text() is called. The content must be converted
5510** to UTF-8.</li>
5511** </ul>
5512**
5513** ^Conversions between UTF-16be and UTF-16le are always done in place and do
5514** not invalidate a prior pointer, though of course the content of the buffer
5515** that the prior pointer references will have been modified. Other kinds
5516** of conversion are done in place when it is possible, but sometimes they
5517** are not possible and in those cases prior pointers are invalidated.
5518**
5519** The safest policy is to invoke these routines
5520** in one of the following ways:
5521**
5522** <ul>
5523** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
5524** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
5525** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
5526** </ul>
5527**
5528** In other words, you should call sqlite3_column_text(),
5529** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
5530** into the desired format, then invoke sqlite3_column_bytes() or
5531** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
5532** to sqlite3_column_text() or sqlite3_column_blob() with calls to
5533** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
5534** with calls to sqlite3_column_bytes().
5535**
5536** ^The pointers returned are valid until a type conversion occurs as
5537** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
5538** [sqlite3_finalize()] is called. ^The memory space used to hold strings
5539** and BLOBs is freed automatically. Do not pass the pointers returned
5540** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
5541** [sqlite3_free()].
5542**
5543** As long as the input parameters are correct, these routines will only
5544** fail if an out-of-memory error occurs during a format conversion.
5545** Only the following subset of interfaces are subject to out-of-memory
5546** errors:
5547**
5548** <ul>
5549** <li> sqlite3_column_blob()
5550** <li> sqlite3_column_text()
5551** <li> sqlite3_column_text16()
5552** <li> sqlite3_column_bytes()
5553** <li> sqlite3_column_bytes16()
5554** </ul>
5555**
5556** If an out-of-memory error occurs, then the return value from these
5557** routines is the same as if the column had contained an SQL NULL value.
5558** Valid SQL NULL returns can be distinguished from out-of-memory errors
5559** by invoking the [sqlite3_errcode()] immediately after the suspect
5560** return value is obtained and before any
5561** other SQLite interface is called on the same [database connection].
5562*/
5563SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
5564SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
5565SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
5566SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
5567SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
5568SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
5569SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
5570SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
5571SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
5572SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
5573
5574/*
5575** CAPI3REF: Destroy A Prepared Statement Object
5576** DESTRUCTOR: sqlite3_stmt
5577**
5578** ^The sqlite3_finalize() function is called to delete a [prepared statement].
5579** ^If the most recent evaluation of the statement encountered no errors
5580** or if the statement is never been evaluated, then sqlite3_finalize() returns
5581** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
5582** sqlite3_finalize(S) returns the appropriate [error code] or
5583** [extended error code].
5584**
5585** ^The sqlite3_finalize(S) routine can be called at any point during
5586** the life cycle of [prepared statement] S:
5587** before statement S is ever evaluated, after
5588** one or more calls to [sqlite3_reset()], or after any call
5589** to [sqlite3_step()] regardless of whether or not the statement has
5590** completed execution.
5591**
5592** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
5593**
5594** The application must finalize every [prepared statement] in order to avoid
5595** resource leaks. It is a grievous error for the application to try to use
5596** a prepared statement after it has been finalized. Any use of a prepared
5597** statement after it has been finalized can result in undefined and
5598** undesirable behavior such as segfaults and heap corruption.
5599*/
5600SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
5601
5602/*
5603** CAPI3REF: Reset A Prepared Statement Object
5604** METHOD: sqlite3_stmt
5605**
5606** The sqlite3_reset() function is called to reset a [prepared statement]
5607** object back to its initial state, ready to be re-executed.
5608** ^Any SQL statement variables that had values bound to them using
5609** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
5610** Use [sqlite3_clear_bindings()] to reset the bindings.
5611**
5612** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
5613** back to the beginning of its program.
5614**
5615** ^The return code from [sqlite3_reset(S)] indicates whether or not
5616** the previous evaluation of prepared statement S completed successfully.
5617** ^If [sqlite3_step(S)] has never before been called on S or if
5618** [sqlite3_step(S)] has not been called since the previous call
5619** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return
5620** [SQLITE_OK].
5621**
5622** ^If the most recent call to [sqlite3_step(S)] for the
5623** [prepared statement] S indicated an error, then
5624** [sqlite3_reset(S)] returns an appropriate [error code].
5625** ^The [sqlite3_reset(S)] interface might also return an [error code]
5626** if there were no prior errors but the process of resetting
5627** the prepared statement caused a new error. ^For example, if an
5628** [INSERT] statement with a [RETURNING] clause is only stepped one time,
5629** that one call to [sqlite3_step(S)] might return SQLITE_ROW but
5630** the overall statement might still fail and the [sqlite3_reset(S)] call
5631** might return SQLITE_BUSY if locking constraints prevent the
5632** database change from committing. Therefore, it is important that
5633** applications check the return code from [sqlite3_reset(S)] even if
5634** no prior call to [sqlite3_step(S)] indicated a problem.
5635**
5636** ^The [sqlite3_reset(S)] interface does not change the values
5637** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
5638*/
5639SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
5640
5641/*
5642** CAPI3REF: Create Or Redefine SQL Functions
5643** KEYWORDS: {function creation routines}
5644** METHOD: sqlite3
5645**
5646** ^These functions (collectively known as "function creation routines")
5647** are used to add SQL functions or aggregates or to redefine the behavior
5648** of existing SQL functions or aggregates. The only differences between
5649** the three "sqlite3_create_function*" routines are the text encoding
5650** expected for the second parameter (the name of the function being
5651** created) and the presence or absence of a destructor callback for
5652** the application data pointer. Function sqlite3_create_window_function()
5653** is similar, but allows the user to supply the extra callback functions
5654** needed by [aggregate window functions].
5655**
5656** ^The first parameter is the [database connection] to which the SQL
5657** function is to be added. ^If an application uses more than one database
5658** connection then application-defined SQL functions must be added
5659** to each database connection separately.
5660**
5661** ^The second parameter is the name of the SQL function to be created or
5662** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
5663** representation, exclusive of the zero-terminator. ^Note that the name
5664** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
5665** ^Any attempt to create a function with a longer name
5666** will result in [SQLITE_MISUSE] being returned.
5667**
5668** ^The third parameter (nArg)
5669** is the number of arguments that the SQL function or
5670** aggregate takes. ^If this parameter is -1, then the SQL function or
5671** aggregate may take any number of arguments between 0 and the limit
5672** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
5673** parameter is less than -1 or greater than 127 then the behavior is
5674** undefined.
5675**
5676** ^The fourth parameter, eTextRep, specifies what
5677** [SQLITE_UTF8 | text encoding] this SQL function prefers for
5678** its parameters. The application should set this parameter to
5679** [SQLITE_UTF16LE] if the function implementation invokes
5680** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
5681** implementation invokes [sqlite3_value_text16be()] on an input, or
5682** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
5683** otherwise. ^The same SQL function may be registered multiple times using
5684** different preferred text encodings, with different implementations for
5685** each encoding.
5686** ^When multiple implementations of the same function are available, SQLite
5687** will pick the one that involves the least amount of data conversion.
5688**
5689** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
5690** to signal that the function will always return the same result given
5691** the same inputs within a single SQL statement. Most SQL functions are
5692** deterministic. The built-in [random()] SQL function is an example of a
5693** function that is not deterministic. The SQLite query planner is able to
5694** perform additional optimizations on deterministic functions, so use
5695** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
5696**
5697** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY]
5698** flag, which if present prevents the function from being invoked from
5699** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions,
5700** index expressions, or the WHERE clause of partial indexes.
5701**
5702** For best security, the [SQLITE_DIRECTONLY] flag is recommended for
5703** all application-defined SQL functions that do not need to be
5704** used inside of triggers, view, CHECK constraints, or other elements of
5705** the database schema. This flags is especially recommended for SQL
5706** functions that have side effects or reveal internal application state.
5707** Without this flag, an attacker might be able to modify the schema of
5708** a database file to include invocations of the function with parameters
5709** chosen by the attacker, which the application will then execute when
5710** the database file is opened and read.
5711**
5712** ^(The fifth parameter is an arbitrary pointer. The implementation of the
5713** function can gain access to this pointer using [sqlite3_user_data()].)^
5714**
5715** ^The sixth, seventh and eighth parameters passed to the three
5716** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
5717** pointers to C-language functions that implement the SQL function or
5718** aggregate. ^A scalar SQL function requires an implementation of the xFunc
5719** callback only; NULL pointers must be passed as the xStep and xFinal
5720** parameters. ^An aggregate SQL function requires an implementation of xStep
5721** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
5722** SQL function or aggregate, pass NULL pointers for all three function
5723** callbacks.
5724**
5725** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
5726** and xInverse) passed to sqlite3_create_window_function are pointers to
5727** C-language callbacks that implement the new function. xStep and xFinal
5728** must both be non-NULL. xValue and xInverse may either both be NULL, in
5729** which case a regular aggregate function is created, or must both be
5730** non-NULL, in which case the new function may be used as either an aggregate
5731** or aggregate window function. More details regarding the implementation
5732** of aggregate window functions are
5733** [user-defined window functions|available here].
5734**
5735** ^(If the final parameter to sqlite3_create_function_v2() or
5736** sqlite3_create_window_function() is not NULL, then it is destructor for
5737** the application data pointer. The destructor is invoked when the function
5738** is deleted, either by being overloaded or when the database connection
5739** closes.)^ ^The destructor is also invoked if the call to
5740** sqlite3_create_function_v2() fails. ^When the destructor callback is
5741** invoked, it is passed a single argument which is a copy of the application
5742** data pointer which was the fifth parameter to sqlite3_create_function_v2().
5743**
5744** ^It is permitted to register multiple implementations of the same
5745** functions with the same name but with either differing numbers of
5746** arguments or differing preferred text encodings. ^SQLite will use
5747** the implementation that most closely matches the way in which the
5748** SQL function is used. ^A function implementation with a non-negative
5749** nArg parameter is a better match than a function implementation with
5750** a negative nArg. ^A function where the preferred text encoding
5751** matches the database encoding is a better
5752** match than a function where the encoding is different.
5753** ^A function where the encoding difference is between UTF16le and UTF16be
5754** is a closer match than a function where the encoding difference is
5755** between UTF8 and UTF16.
5756**
5757** ^Built-in functions may be overloaded by new application-defined functions.
5758**
5759** ^An application-defined function is permitted to call other
5760** SQLite interfaces. However, such calls must not
5761** close the database connection nor finalize or reset the prepared
5762** statement in which the function is running.
5763*/
5764SQLITE_API int sqlite3_create_function(
5765 sqlite3 *db,
5766 const char *zFunctionName,
5767 int nArg,
5768 int eTextRep,
5769 void *pApp,
5770 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5771 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5772 void (*xFinal)(sqlite3_context*)
5773);
5774SQLITE_API int sqlite3_create_function16(
5775 sqlite3 *db,
5776 const void *zFunctionName,
5777 int nArg,
5778 int eTextRep,
5779 void *pApp,
5780 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5781 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5782 void (*xFinal)(sqlite3_context*)
5783);
5784SQLITE_API int sqlite3_create_function_v2(
5785 sqlite3 *db,
5786 const char *zFunctionName,
5787 int nArg,
5788 int eTextRep,
5789 void *pApp,
5790 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5791 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5792 void (*xFinal)(sqlite3_context*),
5793 void(*xDestroy)(void*)
5794);
5795SQLITE_API int sqlite3_create_window_function(
5796 sqlite3 *db,
5797 const char *zFunctionName,
5798 int nArg,
5799 int eTextRep,
5800 void *pApp,
5801 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5802 void (*xFinal)(sqlite3_context*),
5803 void (*xValue)(sqlite3_context*),
5804 void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
5805 void(*xDestroy)(void*)
5806);
5807
5808/*
5809** CAPI3REF: Text Encodings
5810**
5811** These constant define integer codes that represent the various
5812** text encodings supported by SQLite.
5813*/
5814#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */
5815#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */
5816#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */
5817#define SQLITE_UTF16 4 /* Use native byte order */
5818#define SQLITE_ANY 5 /* Deprecated */
5819#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
5820
5821/*
5822** CAPI3REF: Function Flags
5823**
5824** These constants may be ORed together with the
5825** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
5826** to [sqlite3_create_function()], [sqlite3_create_function16()], or
5827** [sqlite3_create_function_v2()].
5828**
5829** <dl>
5830** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd>
5831** The SQLITE_DETERMINISTIC flag means that the new function always gives
5832** the same output when the input parameters are the same.
5833** The [abs|abs() function] is deterministic, for example, but
5834** [randomblob|randomblob()] is not. Functions must
5835** be deterministic in order to be used in certain contexts such as
5836** with the WHERE clause of [partial indexes] or in [generated columns].
5837** SQLite might also optimize deterministic functions by factoring them
5838** out of inner loops.
5839** </dd>
5840**
5841** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
5842** The SQLITE_DIRECTONLY flag means that the function may only be invoked
5843** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
5844** schema structures such as [CHECK constraints], [DEFAULT clauses],
5845** [expression indexes], [partial indexes], or [generated columns].
5846** <p>
5847** The SQLITE_DIRECTONLY flag is recommended for any
5848** [application-defined SQL function]
5849** that has side-effects or that could potentially leak sensitive information.
5850** This will prevent attacks in which an application is tricked
5851** into using a database file that has had its schema surreptitiously
5852** modified to invoke the application-defined function in ways that are
5853** harmful.
5854** <p>
5855** Some people say it is good practice to set SQLITE_DIRECTONLY on all
5856** [application-defined SQL functions], regardless of whether or not they
5857** are security sensitive, as doing so prevents those functions from being used
5858** inside of the database schema, and thus ensures that the database
5859** can be inspected and modified using generic tools (such as the [CLI])
5860** that do not have access to the application-defined functions.
5861** </dd>
5862**
5863** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
5864** The SQLITE_INNOCUOUS flag means that the function is unlikely
5865** to cause problems even if misused. An innocuous function should have
5866** no side effects and should not depend on any values other than its
5867** input parameters. The [abs|abs() function] is an example of an
5868** innocuous function.
5869** The [load_extension() SQL function] is not innocuous because of its
5870** side effects.
5871** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not
5872** exactly the same. The [random|random() function] is an example of a
5873** function that is innocuous but not deterministic.
5874** <p>Some heightened security settings
5875** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF])
5876** disable the use of SQL functions inside views and triggers and in
5877** schema structures such as [CHECK constraints], [DEFAULT clauses],
5878** [expression indexes], [partial indexes], and [generated columns] unless
5879** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions
5880** are innocuous. Developers are advised to avoid using the
5881** SQLITE_INNOCUOUS flag for application-defined functions unless the
5882** function has been carefully audited and found to be free of potentially
5883** security-adverse side-effects and information-leaks.
5884** </dd>
5885**
5886** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
5887** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call
5888** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
5889** Specifying this flag makes no difference for scalar or aggregate user
5890** functions. However, if it is not specified for a user-defined window
5891** function, then any sub-types belonging to arguments passed to the window
5892** function may be discarded before the window function is called (i.e.
5893** sqlite3_value_subtype() will always return 0).
5894** </dd>
5895** </dl>
5896*/
5897#define SQLITE_DETERMINISTIC 0x000000800
5898#define SQLITE_DIRECTONLY 0x000080000
5899#define SQLITE_SUBTYPE 0x000100000
5900#define SQLITE_INNOCUOUS 0x000200000
5901
5902/*
5903** CAPI3REF: Deprecated Functions
5904** DEPRECATED
5905**
5906** These functions are [deprecated]. In order to maintain
5907** backwards compatibility with older code, these functions continue
5908** to be supported. However, new applications should avoid
5909** the use of these functions. To encourage programmers to avoid
5910** these functions, we will not explain what they do.
5911*/
5912#ifndef SQLITE_OMIT_DEPRECATED
5913SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
5914SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
5915SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
5916SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
5917SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
5918SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
5919 void*,sqlite3_int64);
5920#endif
5921
5922/*
5923** CAPI3REF: Obtaining SQL Values
5924** METHOD: sqlite3_value
5925**
5926** <b>Summary:</b>
5927** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5928** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
5929** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
5930** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
5931** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
5932** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
5933** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
5934** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
5935** the native byteorder
5936** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
5937** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
5938** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5939** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
5940** or a UTF-8 TEXT in bytes
5941** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
5942** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5943** TEXT in bytes
5944** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
5945** datatype of the value
5946** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
5947** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
5948** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
5949** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
5950** against a virtual table.
5951** <tr><td><b>sqlite3_value_frombind&nbsp;&nbsp;</b>
5952** <td>&rarr;&nbsp;&nbsp;<td>True if value originated from a [bound parameter]
5953** </table></blockquote>
5954**
5955** <b>Details:</b>
5956**
5957** These routines extract type, size, and content information from
5958** [protected sqlite3_value] objects. Protected sqlite3_value objects
5959** are used to pass parameter information into the functions that
5960** implement [application-defined SQL functions] and [virtual tables].
5961**
5962** These routines work only with [protected sqlite3_value] objects.
5963** Any attempt to use these routines on an [unprotected sqlite3_value]
5964** is not threadsafe.
5965**
5966** ^These routines work just like the corresponding [column access functions]
5967** except that these routines take a single [protected sqlite3_value] object
5968** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
5969**
5970** ^The sqlite3_value_text16() interface extracts a UTF-16 string
5971** in the native byte-order of the host machine. ^The
5972** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
5973** extract UTF-16 strings as big-endian and little-endian respectively.
5974**
5975** ^If [sqlite3_value] object V was initialized
5976** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
5977** and if X and Y are strings that compare equal according to strcmp(X,Y),
5978** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise,
5979** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
5980** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5981**
5982** ^(The sqlite3_value_type(V) interface returns the
5983** [SQLITE_INTEGER | datatype code] for the initial datatype of the
5984** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
5985** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
5986** Other interfaces might change the datatype for an sqlite3_value object.
5987** For example, if the datatype is initially SQLITE_INTEGER and
5988** sqlite3_value_text(V) is called to extract a text value for that
5989** integer, then subsequent calls to sqlite3_value_type(V) might return
5990** SQLITE_TEXT. Whether or not a persistent internal datatype conversion
5991** occurs is undefined and may change from one release of SQLite to the next.
5992**
5993** ^(The sqlite3_value_numeric_type() interface attempts to apply
5994** numeric affinity to the value. This means that an attempt is
5995** made to convert the value to an integer or floating point. If
5996** such a conversion is possible without loss of information (in other
5997** words, if the value is a string that looks like a number)
5998** then the conversion is performed. Otherwise no conversion occurs.
5999** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
6000**
6001** ^Within the [xUpdate] method of a [virtual table], the
6002** sqlite3_value_nochange(X) interface returns true if and only if
6003** the column corresponding to X is unchanged by the UPDATE operation
6004** that the xUpdate method call was invoked to implement and if
6005** and the prior [xColumn] method call that was invoked to extracted
6006** the value for that column returned without setting a result (probably
6007** because it queried [sqlite3_vtab_nochange()] and found that the column
6008** was unchanging). ^Within an [xUpdate] method, any value for which
6009** sqlite3_value_nochange(X) is true will in all other respects appear
6010** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other
6011** than within an [xUpdate] method call for an UPDATE statement, then
6012** the return value is arbitrary and meaningless.
6013**
6014** ^The sqlite3_value_frombind(X) interface returns non-zero if the
6015** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
6016** interfaces. ^If X comes from an SQL literal value, or a table column,
6017** or an expression, then sqlite3_value_frombind(X) returns zero.
6018**
6019** Please pay particular attention to the fact that the pointer returned
6020** from [sqlite3_value_blob()], [sqlite3_value_text()], or
6021** [sqlite3_value_text16()] can be invalidated by a subsequent call to
6022** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
6023** or [sqlite3_value_text16()].
6024**
6025** These routines must be called from the same thread as
6026** the SQL function that supplied the [sqlite3_value*] parameters.
6027**
6028** As long as the input parameter is correct, these routines can only
6029** fail if an out-of-memory error occurs during a format conversion.
6030** Only the following subset of interfaces are subject to out-of-memory
6031** errors:
6032**
6033** <ul>
6034** <li> sqlite3_value_blob()
6035** <li> sqlite3_value_text()
6036** <li> sqlite3_value_text16()
6037** <li> sqlite3_value_text16le()
6038** <li> sqlite3_value_text16be()
6039** <li> sqlite3_value_bytes()
6040** <li> sqlite3_value_bytes16()
6041** </ul>
6042**
6043** If an out-of-memory error occurs, then the return value from these
6044** routines is the same as if the column had contained an SQL NULL value.
6045** Valid SQL NULL returns can be distinguished from out-of-memory errors
6046** by invoking the [sqlite3_errcode()] immediately after the suspect
6047** return value is obtained and before any
6048** other SQLite interface is called on the same [database connection].
6049*/
6050SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
6051SQLITE_API double sqlite3_value_double(sqlite3_value*);
6052SQLITE_API int sqlite3_value_int(sqlite3_value*);
6053SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
6054SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
6055SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
6056SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
6057SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
6058SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
6059SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
6060SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
6061SQLITE_API int sqlite3_value_type(sqlite3_value*);
6062SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
6063SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
6064SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
6065
6066/*
6067** CAPI3REF: Report the internal text encoding state of an sqlite3_value object
6068** METHOD: sqlite3_value
6069**
6070** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8],
6071** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding
6072** of the value X, assuming that X has type TEXT.)^ If sqlite3_value_type(X)
6073** returns something other than SQLITE_TEXT, then the return value from
6074** sqlite3_value_encoding(X) is meaningless. ^Calls to
6075** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)],
6076** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or
6077** [sqlite3_value_bytes16(X)] might change the encoding of the value X and
6078** thus change the return from subsequent calls to sqlite3_value_encoding(X).
6079**
6080** This routine is intended for used by applications that test and validate
6081** the SQLite implementation. This routine is inquiring about the opaque
6082** internal state of an [sqlite3_value] object. Ordinary applications should
6083** not need to know what the internal state of an sqlite3_value object is and
6084** hence should not need to use this interface.
6085*/
6086SQLITE_API int sqlite3_value_encoding(sqlite3_value*);
6087
6088/*
6089** CAPI3REF: Finding The Subtype Of SQL Values
6090** METHOD: sqlite3_value
6091**
6092** The sqlite3_value_subtype(V) function returns the subtype for
6093** an [application-defined SQL function] argument V. The subtype
6094** information can be used to pass a limited amount of context from
6095** one SQL function to another. Use the [sqlite3_result_subtype()]
6096** routine to set the subtype for the return value of an SQL function.
6097*/
6098SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
6099
6100/*
6101** CAPI3REF: Copy And Free SQL Values
6102** METHOD: sqlite3_value
6103**
6104** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
6105** object D and returns a pointer to that copy. ^The [sqlite3_value] returned
6106** is a [protected sqlite3_value] object even if the input is not.
6107** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
6108** memory allocation fails. ^If V is a [pointer value], then the result
6109** of sqlite3_value_dup(V) is a NULL value.
6110**
6111** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
6112** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer
6113** then sqlite3_value_free(V) is a harmless no-op.
6114*/
6115SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
6116SQLITE_API void sqlite3_value_free(sqlite3_value*);
6117
6118/*
6119** CAPI3REF: Obtain Aggregate Function Context
6120** METHOD: sqlite3_context
6121**
6122** Implementations of aggregate SQL functions use this
6123** routine to allocate memory for storing their state.
6124**
6125** ^The first time the sqlite3_aggregate_context(C,N) routine is called
6126** for a particular aggregate function, SQLite allocates
6127** N bytes of memory, zeroes out that memory, and returns a pointer
6128** to the new memory. ^On second and subsequent calls to
6129** sqlite3_aggregate_context() for the same aggregate function instance,
6130** the same buffer is returned. Sqlite3_aggregate_context() is normally
6131** called once for each invocation of the xStep callback and then one
6132** last time when the xFinal callback is invoked. ^(When no rows match
6133** an aggregate query, the xStep() callback of the aggregate function
6134** implementation is never called and xFinal() is called exactly once.
6135** In those cases, sqlite3_aggregate_context() might be called for the
6136** first time from within xFinal().)^
6137**
6138** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
6139** when first called if N is less than or equal to zero or if a memory
6140** allocation error occurs.
6141**
6142** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
6143** determined by the N parameter on first successful call. Changing the
6144** value of N in any subsequent call to sqlite3_aggregate_context() within
6145** the same aggregate function instance will not resize the memory
6146** allocation.)^ Within the xFinal callback, it is customary to set
6147** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
6148** pointless memory allocations occur.
6149**
6150** ^SQLite automatically frees the memory allocated by
6151** sqlite3_aggregate_context() when the aggregate query concludes.
6152**
6153** The first parameter must be a copy of the
6154** [sqlite3_context | SQL function context] that is the first parameter
6155** to the xStep or xFinal callback routine that implements the aggregate
6156** function.
6157**
6158** This routine must be called from the same thread in which
6159** the aggregate SQL function is running.
6160*/
6161SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
6162
6163/*
6164** CAPI3REF: User Data For Functions
6165** METHOD: sqlite3_context
6166**
6167** ^The sqlite3_user_data() interface returns a copy of
6168** the pointer that was the pUserData parameter (the 5th parameter)
6169** of the [sqlite3_create_function()]
6170** and [sqlite3_create_function16()] routines that originally
6171** registered the application defined function.
6172**
6173** This routine must be called from the same thread in which
6174** the application-defined function is running.
6175*/
6176SQLITE_API void *sqlite3_user_data(sqlite3_context*);
6177
6178/*
6179** CAPI3REF: Database Connection For Functions
6180** METHOD: sqlite3_context
6181**
6182** ^The sqlite3_context_db_handle() interface returns a copy of
6183** the pointer to the [database connection] (the 1st parameter)
6184** of the [sqlite3_create_function()]
6185** and [sqlite3_create_function16()] routines that originally
6186** registered the application defined function.
6187*/
6188SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
6189
6190/*
6191** CAPI3REF: Function Auxiliary Data
6192** METHOD: sqlite3_context
6193**
6194** These functions may be used by (non-aggregate) SQL functions to
6195** associate metadata with argument values. If the same value is passed to
6196** multiple invocations of the same SQL function during query execution, under
6197** some circumstances the associated metadata may be preserved. An example
6198** of where this might be useful is in a regular-expression matching
6199** function. The compiled version of the regular expression can be stored as
6200** metadata associated with the pattern string.
6201** Then as long as the pattern string remains the same,
6202** the compiled regular expression can be reused on multiple
6203** invocations of the same function.
6204**
6205** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
6206** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
6207** value to the application-defined function. ^N is zero for the left-most
6208** function argument. ^If there is no metadata
6209** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
6210** returns a NULL pointer.
6211**
6212** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
6213** argument of the application-defined function. ^Subsequent
6214** calls to sqlite3_get_auxdata(C,N) return P from the most recent
6215** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
6216** NULL if the metadata has been discarded.
6217** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
6218** SQLite will invoke the destructor function X with parameter P exactly
6219** once, when the metadata is discarded.
6220** SQLite is free to discard the metadata at any time, including: <ul>
6221** <li> ^(when the corresponding function parameter changes)^, or
6222** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
6223** SQL statement)^, or
6224** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
6225** parameter)^, or
6226** <li> ^(during the original sqlite3_set_auxdata() call when a memory
6227** allocation error occurs.)^ </ul>
6228**
6229** Note the last bullet in particular. The destructor X in
6230** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
6231** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
6232** should be called near the end of the function implementation and the
6233** function implementation should not make any use of P after
6234** sqlite3_set_auxdata() has been called.
6235**
6236** ^(In practice, metadata is preserved between function calls for
6237** function parameters that are compile-time constants, including literal
6238** values and [parameters] and expressions composed from the same.)^
6239**
6240** The value of the N parameter to these interfaces should be non-negative.
6241** Future enhancements may make use of negative N values to define new
6242** kinds of function caching behavior.
6243**
6244** These routines must be called from the same thread in which
6245** the SQL function is running.
6246*/
6247SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
6248SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
6249
6250
6251/*
6252** CAPI3REF: Constants Defining Special Destructor Behavior
6253**
6254** These are special values for the destructor that is passed in as the
6255** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
6256** argument is SQLITE_STATIC, it means that the content pointer is constant
6257** and will never change. It does not need to be destroyed. ^The
6258** SQLITE_TRANSIENT value means that the content will likely change in
6259** the near future and that SQLite should make its own private copy of
6260** the content before returning.
6261**
6262** The typedef is necessary to work around problems in certain
6263** C++ compilers.
6264*/
6265typedef void (*sqlite3_destructor_type)(void*);
6266#define SQLITE_STATIC ((sqlite3_destructor_type)0)
6267#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
6268
6269/*
6270** CAPI3REF: Setting The Result Of An SQL Function
6271** METHOD: sqlite3_context
6272**
6273** These routines are used by the xFunc or xFinal callbacks that
6274** implement SQL functions and aggregates. See
6275** [sqlite3_create_function()] and [sqlite3_create_function16()]
6276** for additional information.
6277**
6278** These functions work very much like the [parameter binding] family of
6279** functions used to bind values to host parameters in prepared statements.
6280** Refer to the [SQL parameter] documentation for additional information.
6281**
6282** ^The sqlite3_result_blob() interface sets the result from
6283** an application-defined function to be the BLOB whose content is pointed
6284** to by the second parameter and which is N bytes long where N is the
6285** third parameter.
6286**
6287** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
6288** interfaces set the result of the application-defined function to be
6289** a BLOB containing all zero bytes and N bytes in size.
6290**
6291** ^The sqlite3_result_double() interface sets the result from
6292** an application-defined function to be a floating point value specified
6293** by its 2nd argument.
6294**
6295** ^The sqlite3_result_error() and sqlite3_result_error16() functions
6296** cause the implemented SQL function to throw an exception.
6297** ^SQLite uses the string pointed to by the
6298** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
6299** as the text of an error message. ^SQLite interprets the error
6300** message string from sqlite3_result_error() as UTF-8. ^SQLite
6301** interprets the string from sqlite3_result_error16() as UTF-16 using
6302** the same [byte-order determination rules] as [sqlite3_bind_text16()].
6303** ^If the third parameter to sqlite3_result_error()
6304** or sqlite3_result_error16() is negative then SQLite takes as the error
6305** message all text up through the first zero character.
6306** ^If the third parameter to sqlite3_result_error() or
6307** sqlite3_result_error16() is non-negative then SQLite takes that many
6308** bytes (not characters) from the 2nd parameter as the error message.
6309** ^The sqlite3_result_error() and sqlite3_result_error16()
6310** routines make a private copy of the error message text before
6311** they return. Hence, the calling function can deallocate or
6312** modify the text after they return without harm.
6313** ^The sqlite3_result_error_code() function changes the error code
6314** returned by SQLite as a result of an error in a function. ^By default,
6315** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
6316** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
6317**
6318** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
6319** error indicating that a string or BLOB is too long to represent.
6320**
6321** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
6322** error indicating that a memory allocation failed.
6323**
6324** ^The sqlite3_result_int() interface sets the return value
6325** of the application-defined function to be the 32-bit signed integer
6326** value given in the 2nd argument.
6327** ^The sqlite3_result_int64() interface sets the return value
6328** of the application-defined function to be the 64-bit signed integer
6329** value given in the 2nd argument.
6330**
6331** ^The sqlite3_result_null() interface sets the return value
6332** of the application-defined function to be NULL.
6333**
6334** ^The sqlite3_result_text(), sqlite3_result_text16(),
6335** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
6336** set the return value of the application-defined function to be
6337** a text string which is represented as UTF-8, UTF-16 native byte order,
6338** UTF-16 little endian, or UTF-16 big endian, respectively.
6339** ^The sqlite3_result_text64() interface sets the return value of an
6340** application-defined function to be a text string in an encoding
6341** specified by the fifth (and last) parameter, which must be one
6342** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
6343** ^SQLite takes the text result from the application from
6344** the 2nd parameter of the sqlite3_result_text* interfaces.
6345** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces
6346** other than sqlite3_result_text64() is negative, then SQLite computes
6347** the string length itself by searching the 2nd parameter for the first
6348** zero character.
6349** ^If the 3rd parameter to the sqlite3_result_text* interfaces
6350** is non-negative, then as many bytes (not characters) of the text
6351** pointed to by the 2nd parameter are taken as the application-defined
6352** function result. If the 3rd parameter is non-negative, then it
6353** must be the byte offset into the string where the NUL terminator would
6354** appear if the string where NUL terminated. If any NUL characters occur
6355** in the string at a byte offset that is less than the value of the 3rd
6356** parameter, then the resulting string will contain embedded NULs and the
6357** result of expressions operating on strings with embedded NULs is undefined.
6358** ^If the 4th parameter to the sqlite3_result_text* interfaces
6359** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
6360** function as the destructor on the text or BLOB result when it has
6361** finished using that result.
6362** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
6363** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
6364** assumes that the text or BLOB result is in constant space and does not
6365** copy the content of the parameter nor call a destructor on the content
6366** when it has finished using that result.
6367** ^If the 4th parameter to the sqlite3_result_text* interfaces
6368** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
6369** then SQLite makes a copy of the result into space obtained
6370** from [sqlite3_malloc()] before it returns.
6371**
6372** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and
6373** sqlite3_result_text16be() routines, and for sqlite3_result_text64()
6374** when the encoding is not UTF8, if the input UTF16 begins with a
6375** byte-order mark (BOM, U+FEFF) then the BOM is removed from the
6376** string and the rest of the string is interpreted according to the
6377** byte-order specified by the BOM. ^The byte-order specified by
6378** the BOM at the beginning of the text overrides the byte-order
6379** specified by the interface procedure. ^So, for example, if
6380** sqlite3_result_text16le() is invoked with text that begins
6381** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the
6382** first two bytes of input are skipped and the remaining input
6383** is interpreted as UTF16BE text.
6384**
6385** ^For UTF16 input text to the sqlite3_result_text16(),
6386** sqlite3_result_text16be(), sqlite3_result_text16le(), and
6387** sqlite3_result_text64() routines, if the text contains invalid
6388** UTF16 characters, the invalid characters might be converted
6389** into the unicode replacement character, U+FFFD.
6390**
6391** ^The sqlite3_result_value() interface sets the result of
6392** the application-defined function to be a copy of the
6393** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
6394** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
6395** so that the [sqlite3_value] specified in the parameter may change or
6396** be deallocated after sqlite3_result_value() returns without harm.
6397** ^A [protected sqlite3_value] object may always be used where an
6398** [unprotected sqlite3_value] object is required, so either
6399** kind of [sqlite3_value] object can be used with this interface.
6400**
6401** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
6402** SQL NULL value, just like [sqlite3_result_null(C)], except that it
6403** also associates the host-language pointer P or type T with that
6404** NULL value such that the pointer can be retrieved within an
6405** [application-defined SQL function] using [sqlite3_value_pointer()].
6406** ^If the D parameter is not NULL, then it is a pointer to a destructor
6407** for the P parameter. ^SQLite invokes D with P as its only argument
6408** when SQLite is finished with P. The T parameter should be a static
6409** string and preferably a string literal. The sqlite3_result_pointer()
6410** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
6411**
6412** If these routines are called from within the different thread
6413** than the one containing the application-defined function that received
6414** the [sqlite3_context] pointer, the results are undefined.
6415*/
6416SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
6417SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
6418 sqlite3_uint64,void(*)(void*));
6419SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
6420SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
6421SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
6422SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
6423SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
6424SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
6425SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
6426SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
6427SQLITE_API void sqlite3_result_null(sqlite3_context*);
6428SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
6429SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
6430 void(*)(void*), unsigned char encoding);
6431SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
6432SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
6433SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
6434SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
6435SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
6436SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
6437SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
6438
6439
6440/*
6441** CAPI3REF: Setting The Subtype Of An SQL Function
6442** METHOD: sqlite3_context
6443**
6444** The sqlite3_result_subtype(C,T) function causes the subtype of
6445** the result from the [application-defined SQL function] with
6446** [sqlite3_context] C to be the value T. Only the lower 8 bits
6447** of the subtype T are preserved in current versions of SQLite;
6448** higher order bits are discarded.
6449** The number of subtype bytes preserved by SQLite might increase
6450** in future releases of SQLite.
6451*/
6452SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
6453
6454/*
6455** CAPI3REF: Define New Collating Sequences
6456** METHOD: sqlite3
6457**
6458** ^These functions add, remove, or modify a [collation] associated
6459** with the [database connection] specified as the first argument.
6460**
6461** ^The name of the collation is a UTF-8 string
6462** for sqlite3_create_collation() and sqlite3_create_collation_v2()
6463** and a UTF-16 string in native byte order for sqlite3_create_collation16().
6464** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
6465** considered to be the same name.
6466**
6467** ^(The third argument (eTextRep) must be one of the constants:
6468** <ul>
6469** <li> [SQLITE_UTF8],
6470** <li> [SQLITE_UTF16LE],
6471** <li> [SQLITE_UTF16BE],
6472** <li> [SQLITE_UTF16], or
6473** <li> [SQLITE_UTF16_ALIGNED].
6474** </ul>)^
6475** ^The eTextRep argument determines the encoding of strings passed
6476** to the collating function callback, xCompare.
6477** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
6478** force strings to be UTF16 with native byte order.
6479** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
6480** on an even byte address.
6481**
6482** ^The fourth argument, pArg, is an application data pointer that is passed
6483** through as the first argument to the collating function callback.
6484**
6485** ^The fifth argument, xCompare, is a pointer to the collating function.
6486** ^Multiple collating functions can be registered using the same name but
6487** with different eTextRep parameters and SQLite will use whichever
6488** function requires the least amount of data transformation.
6489** ^If the xCompare argument is NULL then the collating function is
6490** deleted. ^When all collating functions having the same name are deleted,
6491** that collation is no longer usable.
6492**
6493** ^The collating function callback is invoked with a copy of the pArg
6494** application data pointer and with two strings in the encoding specified
6495** by the eTextRep argument. The two integer parameters to the collating
6496** function callback are the length of the two strings, in bytes. The collating
6497** function must return an integer that is negative, zero, or positive
6498** if the first string is less than, equal to, or greater than the second,
6499** respectively. A collating function must always return the same answer
6500** given the same inputs. If two or more collating functions are registered
6501** to the same collation name (using different eTextRep values) then all
6502** must give an equivalent answer when invoked with equivalent strings.
6503** The collating function must obey the following properties for all
6504** strings A, B, and C:
6505**
6506** <ol>
6507** <li> If A==B then B==A.
6508** <li> If A==B and B==C then A==C.
6509** <li> If A&lt;B THEN B&gt;A.
6510** <li> If A&lt;B and B&lt;C then A&lt;C.
6511** </ol>
6512**
6513** If a collating function fails any of the above constraints and that
6514** collating function is registered and used, then the behavior of SQLite
6515** is undefined.
6516**
6517** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
6518** with the addition that the xDestroy callback is invoked on pArg when
6519** the collating function is deleted.
6520** ^Collating functions are deleted when they are overridden by later
6521** calls to the collation creation functions or when the
6522** [database connection] is closed using [sqlite3_close()].
6523**
6524** ^The xDestroy callback is <u>not</u> called if the
6525** sqlite3_create_collation_v2() function fails. Applications that invoke
6526** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
6527** check the return code and dispose of the application data pointer
6528** themselves rather than expecting SQLite to deal with it for them.
6529** This is different from every other SQLite interface. The inconsistency
6530** is unfortunate but cannot be changed without breaking backwards
6531** compatibility.
6532**
6533** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
6534*/
6535SQLITE_API int sqlite3_create_collation(
6536 sqlite3*,
6537 const char *zName,
6538 int eTextRep,
6539 void *pArg,
6540 int(*xCompare)(void*,int,const void*,int,const void*)
6541);
6542SQLITE_API int sqlite3_create_collation_v2(
6543 sqlite3*,
6544 const char *zName,
6545 int eTextRep,
6546 void *pArg,
6547 int(*xCompare)(void*,int,const void*,int,const void*),
6548 void(*xDestroy)(void*)
6549);
6550SQLITE_API int sqlite3_create_collation16(
6551 sqlite3*,
6552 const void *zName,
6553 int eTextRep,
6554 void *pArg,
6555 int(*xCompare)(void*,int,const void*,int,const void*)
6556);
6557
6558/*
6559** CAPI3REF: Collation Needed Callbacks
6560** METHOD: sqlite3
6561**
6562** ^To avoid having to register all collation sequences before a database
6563** can be used, a single callback function may be registered with the
6564** [database connection] to be invoked whenever an undefined collation
6565** sequence is required.
6566**
6567** ^If the function is registered using the sqlite3_collation_needed() API,
6568** then it is passed the names of undefined collation sequences as strings
6569** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
6570** the names are passed as UTF-16 in machine native byte order.
6571** ^A call to either function replaces the existing collation-needed callback.
6572**
6573** ^(When the callback is invoked, the first argument passed is a copy
6574** of the second argument to sqlite3_collation_needed() or
6575** sqlite3_collation_needed16(). The second argument is the database
6576** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
6577** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
6578** sequence function required. The fourth parameter is the name of the
6579** required collation sequence.)^
6580**
6581** The callback function should register the desired collation using
6582** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
6583** [sqlite3_create_collation_v2()].
6584*/
6585SQLITE_API int sqlite3_collation_needed(
6586 sqlite3*,
6587 void*,
6588 void(*)(void*,sqlite3*,int eTextRep,const char*)
6589);
6590SQLITE_API int sqlite3_collation_needed16(
6591 sqlite3*,
6592 void*,
6593 void(*)(void*,sqlite3*,int eTextRep,const void*)
6594);
6595
6596#ifdef SQLITE_ENABLE_CEROD
6597/*
6598** Specify the activation key for a CEROD database. Unless
6599** activated, none of the CEROD routines will work.
6600*/
6601SQLITE_API void sqlite3_activate_cerod(
6602 const char *zPassPhrase /* Activation phrase */
6603);
6604#endif
6605
6606/*
6607** CAPI3REF: Suspend Execution For A Short Time
6608**
6609** The sqlite3_sleep() function causes the current thread to suspend execution
6610** for at least a number of milliseconds specified in its parameter.
6611**
6612** If the operating system does not support sleep requests with
6613** millisecond time resolution, then the time will be rounded up to
6614** the nearest second. The number of milliseconds of sleep actually
6615** requested from the operating system is returned.
6616**
6617** ^SQLite implements this interface by calling the xSleep()
6618** method of the default [sqlite3_vfs] object. If the xSleep() method
6619** of the default VFS is not implemented correctly, or not implemented at
6620** all, then the behavior of sqlite3_sleep() may deviate from the description
6621** in the previous paragraphs.
6622**
6623** If a negative argument is passed to sqlite3_sleep() the results vary by
6624** VFS and operating system. Some system treat a negative argument as an
6625** instruction to sleep forever. Others understand it to mean do not sleep
6626** at all. ^In SQLite version 3.42.0 and later, a negative
6627** argument passed into sqlite3_sleep() is changed to zero before it is relayed
6628** down into the xSleep method of the VFS.
6629*/
6630SQLITE_API int sqlite3_sleep(int);
6631
6632/*
6633** CAPI3REF: Name Of The Folder Holding Temporary Files
6634**
6635** ^(If this global variable is made to point to a string which is
6636** the name of a folder (a.k.a. directory), then all temporary files
6637** created by SQLite when using a built-in [sqlite3_vfs | VFS]
6638** will be placed in that directory.)^ ^If this variable
6639** is a NULL pointer, then SQLite performs a search for an appropriate
6640** temporary file directory.
6641**
6642** Applications are strongly discouraged from using this global variable.
6643** It is required to set a temporary folder on Windows Runtime (WinRT).
6644** But for all other platforms, it is highly recommended that applications
6645** neither read nor write this variable. This global variable is a relic
6646** that exists for backwards compatibility of legacy applications and should
6647** be avoided in new projects.
6648**
6649** It is not safe to read or modify this variable in more than one
6650** thread at a time. It is not safe to read or modify this variable
6651** if a [database connection] is being used at the same time in a separate
6652** thread.
6653** It is intended that this variable be set once
6654** as part of process initialization and before any SQLite interface
6655** routines have been called and that this variable remain unchanged
6656** thereafter.
6657**
6658** ^The [temp_store_directory pragma] may modify this variable and cause
6659** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
6660** the [temp_store_directory pragma] always assumes that any string
6661** that this variable points to is held in memory obtained from
6662** [sqlite3_malloc] and the pragma may attempt to free that memory
6663** using [sqlite3_free].
6664** Hence, if this variable is modified directly, either it should be
6665** made NULL or made to point to memory obtained from [sqlite3_malloc]
6666** or else the use of the [temp_store_directory pragma] should be avoided.
6667** Except when requested by the [temp_store_directory pragma], SQLite
6668** does not free the memory that sqlite3_temp_directory points to. If
6669** the application wants that memory to be freed, it must do
6670** so itself, taking care to only do so after all [database connection]
6671** objects have been destroyed.
6672**
6673** <b>Note to Windows Runtime users:</b> The temporary directory must be set
6674** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
6675** features that require the use of temporary files may fail. Here is an
6676** example of how to do this using C++ with the Windows Runtime:
6677**
6678** <blockquote><pre>
6679** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
6680** &nbsp; TemporaryFolder->Path->Data();
6681** char zPathBuf&#91;MAX_PATH + 1&#93;;
6682** memset(zPathBuf, 0, sizeof(zPathBuf));
6683** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
6684** &nbsp; NULL, NULL);
6685** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
6686** </pre></blockquote>
6687*/
6688SQLITE_API char *sqlite3_temp_directory;
6689
6690/*
6691** CAPI3REF: Name Of The Folder Holding Database Files
6692**
6693** ^(If this global variable is made to point to a string which is
6694** the name of a folder (a.k.a. directory), then all database files
6695** specified with a relative pathname and created or accessed by
6696** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
6697** to be relative to that directory.)^ ^If this variable is a NULL
6698** pointer, then SQLite assumes that all database files specified
6699** with a relative pathname are relative to the current directory
6700** for the process. Only the windows VFS makes use of this global
6701** variable; it is ignored by the unix VFS.
6702**
6703** Changing the value of this variable while a database connection is
6704** open can result in a corrupt database.
6705**
6706** It is not safe to read or modify this variable in more than one
6707** thread at a time. It is not safe to read or modify this variable
6708** if a [database connection] is being used at the same time in a separate
6709** thread.
6710** It is intended that this variable be set once
6711** as part of process initialization and before any SQLite interface
6712** routines have been called and that this variable remain unchanged
6713** thereafter.
6714**
6715** ^The [data_store_directory pragma] may modify this variable and cause
6716** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
6717** the [data_store_directory pragma] always assumes that any string
6718** that this variable points to is held in memory obtained from
6719** [sqlite3_malloc] and the pragma may attempt to free that memory
6720** using [sqlite3_free].
6721** Hence, if this variable is modified directly, either it should be
6722** made NULL or made to point to memory obtained from [sqlite3_malloc]
6723** or else the use of the [data_store_directory pragma] should be avoided.
6724*/
6725SQLITE_API char *sqlite3_data_directory;
6726
6727/*
6728** CAPI3REF: Win32 Specific Interface
6729**
6730** These interfaces are available only on Windows. The
6731** [sqlite3_win32_set_directory] interface is used to set the value associated
6732** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
6733** zValue, depending on the value of the type parameter. The zValue parameter
6734** should be NULL to cause the previous value to be freed via [sqlite3_free];
6735** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
6736** prior to being used. The [sqlite3_win32_set_directory] interface returns
6737** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
6738** or [SQLITE_NOMEM] if memory could not be allocated. The value of the
6739** [sqlite3_data_directory] variable is intended to act as a replacement for
6740** the current directory on the sub-platforms of Win32 where that concept is
6741** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and
6742** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
6743** sqlite3_win32_set_directory interface except the string parameter must be
6744** UTF-8 or UTF-16, respectively.
6745*/
6746SQLITE_API int sqlite3_win32_set_directory(
6747 unsigned long type, /* Identifier for directory being set or reset */
6748 void *zValue /* New value for directory being set or reset */
6749);
6750SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
6751SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
6752
6753/*
6754** CAPI3REF: Win32 Directory Types
6755**
6756** These macros are only available on Windows. They define the allowed values
6757** for the type argument to the [sqlite3_win32_set_directory] interface.
6758*/
6759#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1
6760#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2
6761
6762/*
6763** CAPI3REF: Test For Auto-Commit Mode
6764** KEYWORDS: {autocommit mode}
6765** METHOD: sqlite3
6766**
6767** ^The sqlite3_get_autocommit() interface returns non-zero or
6768** zero if the given database connection is or is not in autocommit mode,
6769** respectively. ^Autocommit mode is on by default.
6770** ^Autocommit mode is disabled by a [BEGIN] statement.
6771** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
6772**
6773** If certain kinds of errors occur on a statement within a multi-statement
6774** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
6775** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
6776** transaction might be rolled back automatically. The only way to
6777** find out whether SQLite automatically rolled back the transaction after
6778** an error is to use this function.
6779**
6780** If another thread changes the autocommit status of the database
6781** connection while this routine is running, then the return value
6782** is undefined.
6783*/
6784SQLITE_API int sqlite3_get_autocommit(sqlite3*);
6785
6786/*
6787** CAPI3REF: Find The Database Handle Of A Prepared Statement
6788** METHOD: sqlite3_stmt
6789**
6790** ^The sqlite3_db_handle interface returns the [database connection] handle
6791** to which a [prepared statement] belongs. ^The [database connection]
6792** returned by sqlite3_db_handle is the same [database connection]
6793** that was the first argument
6794** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
6795** create the statement in the first place.
6796*/
6797SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
6798
6799/*
6800** CAPI3REF: Return The Schema Name For A Database Connection
6801** METHOD: sqlite3
6802**
6803** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name
6804** for the N-th database on database connection D, or a NULL pointer of N is
6805** out of range. An N value of 0 means the main database file. An N of 1 is
6806** the "temp" schema. Larger values of N correspond to various ATTACH-ed
6807** databases.
6808**
6809** Space to hold the string that is returned by sqlite3_db_name() is managed
6810** by SQLite itself. The string might be deallocated by any operation that
6811** changes the schema, including [ATTACH] or [DETACH] or calls to
6812** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that
6813** occur on a different thread. Applications that need to
6814** remember the string long-term should make their own copy. Applications that
6815** are accessing the same database connection simultaneously on multiple
6816** threads should mutex-protect calls to this API and should make their own
6817** private copy of the result prior to releasing the mutex.
6818*/
6819SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N);
6820
6821/*
6822** CAPI3REF: Return The Filename For A Database Connection
6823** METHOD: sqlite3
6824**
6825** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename
6826** associated with database N of connection D.
6827** ^If there is no attached database N on the database
6828** connection D, or if database N is a temporary or in-memory database, then
6829** this function will return either a NULL pointer or an empty string.
6830**
6831** ^The string value returned by this routine is owned and managed by
6832** the database connection. ^The value will be valid until the database N
6833** is [DETACH]-ed or until the database connection closes.
6834**
6835** ^The filename returned by this function is the output of the
6836** xFullPathname method of the [VFS]. ^In other words, the filename
6837** will be an absolute pathname, even if the filename used
6838** to open the database originally was a URI or relative pathname.
6839**
6840** If the filename pointer returned by this routine is not NULL, then it
6841** can be used as the filename input parameter to these routines:
6842** <ul>
6843** <li> [sqlite3_uri_parameter()]
6844** <li> [sqlite3_uri_boolean()]
6845** <li> [sqlite3_uri_int64()]
6846** <li> [sqlite3_filename_database()]
6847** <li> [sqlite3_filename_journal()]
6848** <li> [sqlite3_filename_wal()]
6849** </ul>
6850*/
6851SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName);
6852
6853/*
6854** CAPI3REF: Determine if a database is read-only
6855** METHOD: sqlite3
6856**
6857** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
6858** of connection D is read-only, 0 if it is read/write, or -1 if N is not
6859** the name of a database on connection D.
6860*/
6861SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
6862
6863/*
6864** CAPI3REF: Determine the transaction state of a database
6865** METHOD: sqlite3
6866**
6867** ^The sqlite3_txn_state(D,S) interface returns the current
6868** [transaction state] of schema S in database connection D. ^If S is NULL,
6869** then the highest transaction state of any schema on database connection D
6870** is returned. Transaction states are (in order of lowest to highest):
6871** <ol>
6872** <li value="0"> SQLITE_TXN_NONE
6873** <li value="1"> SQLITE_TXN_READ
6874** <li value="2"> SQLITE_TXN_WRITE
6875** </ol>
6876** ^If the S argument to sqlite3_txn_state(D,S) is not the name of
6877** a valid schema, then -1 is returned.
6878*/
6879SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema);
6880
6881/*
6882** CAPI3REF: Allowed return values from [sqlite3_txn_state()]
6883** KEYWORDS: {transaction state}
6884**
6885** These constants define the current transaction state of a database file.
6886** ^The [sqlite3_txn_state(D,S)] interface returns one of these
6887** constants in order to describe the transaction state of schema S
6888** in [database connection] D.
6889**
6890** <dl>
6891** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt>
6892** <dd>The SQLITE_TXN_NONE state means that no transaction is currently
6893** pending.</dd>
6894**
6895** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt>
6896** <dd>The SQLITE_TXN_READ state means that the database is currently
6897** in a read transaction. Content has been read from the database file
6898** but nothing in the database file has changed. The transaction state
6899** will advanced to SQLITE_TXN_WRITE if any changes occur and there are
6900** no other conflicting concurrent write transactions. The transaction
6901** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or
6902** [COMMIT].</dd>
6903**
6904** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt>
6905** <dd>The SQLITE_TXN_WRITE state means that the database is currently
6906** in a write transaction. Content has been written to the database file
6907** but has not yet committed. The transaction state will change to
6908** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd>
6909*/
6910#define SQLITE_TXN_NONE 0
6911#define SQLITE_TXN_READ 1
6912#define SQLITE_TXN_WRITE 2
6913
6914/*
6915** CAPI3REF: Find the next prepared statement
6916** METHOD: sqlite3
6917**
6918** ^This interface returns a pointer to the next [prepared statement] after
6919** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
6920** then this interface returns a pointer to the first prepared statement
6921** associated with the database connection pDb. ^If no prepared statement
6922** satisfies the conditions of this routine, it returns NULL.
6923**
6924** The [database connection] pointer D in a call to
6925** [sqlite3_next_stmt(D,S)] must refer to an open database
6926** connection and in particular must not be a NULL pointer.
6927*/
6928SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
6929
6930/*
6931** CAPI3REF: Commit And Rollback Notification Callbacks
6932** METHOD: sqlite3
6933**
6934** ^The sqlite3_commit_hook() interface registers a callback
6935** function to be invoked whenever a transaction is [COMMIT | committed].
6936** ^Any callback set by a previous call to sqlite3_commit_hook()
6937** for the same database connection is overridden.
6938** ^The sqlite3_rollback_hook() interface registers a callback
6939** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
6940** ^Any callback set by a previous call to sqlite3_rollback_hook()
6941** for the same database connection is overridden.
6942** ^The pArg argument is passed through to the callback.
6943** ^If the callback on a commit hook function returns non-zero,
6944** then the commit is converted into a rollback.
6945**
6946** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
6947** return the P argument from the previous call of the same function
6948** on the same [database connection] D, or NULL for
6949** the first call for each function on D.
6950**
6951** The commit and rollback hook callbacks are not reentrant.
6952** The callback implementation must not do anything that will modify
6953** the database connection that invoked the callback. Any actions
6954** to modify the database connection must be deferred until after the
6955** completion of the [sqlite3_step()] call that triggered the commit
6956** or rollback hook in the first place.
6957** Note that running any other SQL statements, including SELECT statements,
6958** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
6959** the database connections for the meaning of "modify" in this paragraph.
6960**
6961** ^Registering a NULL function disables the callback.
6962**
6963** ^When the commit hook callback routine returns zero, the [COMMIT]
6964** operation is allowed to continue normally. ^If the commit hook
6965** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
6966** ^The rollback hook is invoked on a rollback that results from a commit
6967** hook returning non-zero, just as it would be with any other rollback.
6968**
6969** ^For the purposes of this API, a transaction is said to have been
6970** rolled back if an explicit "ROLLBACK" statement is executed, or
6971** an error or constraint causes an implicit rollback to occur.
6972** ^The rollback callback is not invoked if a transaction is
6973** automatically rolled back because the database connection is closed.
6974**
6975** See also the [sqlite3_update_hook()] interface.
6976*/
6977SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
6978SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
6979
6980/*
6981** CAPI3REF: Autovacuum Compaction Amount Callback
6982** METHOD: sqlite3
6983**
6984** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback
6985** function C that is invoked prior to each autovacuum of the database
6986** file. ^The callback is passed a copy of the generic data pointer (P),
6987** the schema-name of the attached database that is being autovacuumed,
6988** the size of the database file in pages, the number of free pages,
6989** and the number of bytes per page, respectively. The callback should
6990** return the number of free pages that should be removed by the
6991** autovacuum. ^If the callback returns zero, then no autovacuum happens.
6992** ^If the value returned is greater than or equal to the number of
6993** free pages, then a complete autovacuum happens.
6994**
6995** <p>^If there are multiple ATTACH-ed database files that are being
6996** modified as part of a transaction commit, then the autovacuum pages
6997** callback is invoked separately for each file.
6998**
6999** <p><b>The callback is not reentrant.</b> The callback function should
7000** not attempt to invoke any other SQLite interface. If it does, bad
7001** things may happen, including segmentation faults and corrupt database
7002** files. The callback function should be a simple function that
7003** does some arithmetic on its input parameters and returns a result.
7004**
7005** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional
7006** destructor for the P parameter. ^If X is not NULL, then X(P) is
7007** invoked whenever the database connection closes or when the callback
7008** is overwritten by another invocation of sqlite3_autovacuum_pages().
7009**
7010** <p>^There is only one autovacuum pages callback per database connection.
7011** ^Each call to the sqlite3_autovacuum_pages() interface overrides all
7012** previous invocations for that database connection. ^If the callback
7013** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer,
7014** then the autovacuum steps callback is cancelled. The return value
7015** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might
7016** be some other error code if something goes wrong. The current
7017** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other
7018** return codes might be added in future releases.
7019**
7020** <p>If no autovacuum pages callback is specified (the usual case) or
7021** a NULL pointer is provided for the callback,
7022** then the default behavior is to vacuum all free pages. So, in other
7023** words, the default behavior is the same as if the callback function
7024** were something like this:
7025**
7026** <blockquote><pre>
7027** &nbsp; unsigned int demonstration_autovac_pages_callback(
7028** &nbsp; void *pClientData,
7029** &nbsp; const char *zSchema,
7030** &nbsp; unsigned int nDbPage,
7031** &nbsp; unsigned int nFreePage,
7032** &nbsp; unsigned int nBytePerPage
7033** &nbsp; ){
7034** &nbsp; return nFreePage;
7035** &nbsp; }
7036** </pre></blockquote>
7037*/
7038SQLITE_API int sqlite3_autovacuum_pages(
7039 sqlite3 *db,
7040 unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int),
7041 void*,
7042 void(*)(void*)
7043);
7044
7045
7046/*
7047** CAPI3REF: Data Change Notification Callbacks
7048** METHOD: sqlite3
7049**
7050** ^The sqlite3_update_hook() interface registers a callback function
7051** with the [database connection] identified by the first argument
7052** to be invoked whenever a row is updated, inserted or deleted in
7053** a [rowid table].
7054** ^Any callback set by a previous call to this function
7055** for the same database connection is overridden.
7056**
7057** ^The second argument is a pointer to the function to invoke when a
7058** row is updated, inserted or deleted in a rowid table.
7059** ^The first argument to the callback is a copy of the third argument
7060** to sqlite3_update_hook().
7061** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
7062** or [SQLITE_UPDATE], depending on the operation that caused the callback
7063** to be invoked.
7064** ^The third and fourth arguments to the callback contain pointers to the
7065** database and table name containing the affected row.
7066** ^The final callback parameter is the [rowid] of the row.
7067** ^In the case of an update, this is the [rowid] after the update takes place.
7068**
7069** ^(The update hook is not invoked when internal system tables are
7070** modified (i.e. sqlite_sequence).)^
7071** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
7072**
7073** ^In the current implementation, the update hook
7074** is not invoked when conflicting rows are deleted because of an
7075** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
7076** invoked when rows are deleted using the [truncate optimization].
7077** The exceptions defined in this paragraph might change in a future
7078** release of SQLite.
7079**
7080** The update hook implementation must not do anything that will modify
7081** the database connection that invoked the update hook. Any actions
7082** to modify the database connection must be deferred until after the
7083** completion of the [sqlite3_step()] call that triggered the update hook.
7084** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
7085** database connections for the meaning of "modify" in this paragraph.
7086**
7087** ^The sqlite3_update_hook(D,C,P) function
7088** returns the P argument from the previous call
7089** on the same [database connection] D, or NULL for
7090** the first call on D.
7091**
7092** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
7093** and [sqlite3_preupdate_hook()] interfaces.
7094*/
7095SQLITE_API void *sqlite3_update_hook(
7096 sqlite3*,
7097 void(*)(void *,int ,char const *,char const *,sqlite3_int64),
7098 void*
7099);
7100
7101/*
7102** CAPI3REF: Enable Or Disable Shared Pager Cache
7103**
7104** ^(This routine enables or disables the sharing of the database cache
7105** and schema data structures between [database connection | connections]
7106** to the same database. Sharing is enabled if the argument is true
7107** and disabled if the argument is false.)^
7108**
7109** This interface is omitted if SQLite is compiled with
7110** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE]
7111** compile-time option is recommended because the
7112** [use of shared cache mode is discouraged].
7113**
7114** ^Cache sharing is enabled and disabled for an entire process.
7115** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
7116** In prior versions of SQLite,
7117** sharing was enabled or disabled for each thread separately.
7118**
7119** ^(The cache sharing mode set by this interface effects all subsequent
7120** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
7121** Existing database connections continue to use the sharing mode
7122** that was in effect at the time they were opened.)^
7123**
7124** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
7125** successfully. An [error code] is returned otherwise.)^
7126**
7127** ^Shared cache is disabled by default. It is recommended that it stay
7128** that way. In other words, do not use this routine. This interface
7129** continues to be provided for historical compatibility, but its use is
7130** discouraged. Any use of shared cache is discouraged. If shared cache
7131** must be used, it is recommended that shared cache only be enabled for
7132** individual database connections using the [sqlite3_open_v2()] interface
7133** with the [SQLITE_OPEN_SHAREDCACHE] flag.
7134**
7135** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
7136** and will always return SQLITE_MISUSE. On those systems,
7137** shared cache mode should be enabled per-database connection via
7138** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
7139**
7140** This interface is threadsafe on processors where writing a
7141** 32-bit integer is atomic.
7142**
7143** See Also: [SQLite Shared-Cache Mode]
7144*/
7145SQLITE_API int sqlite3_enable_shared_cache(int);
7146
7147/*
7148** CAPI3REF: Attempt To Free Heap Memory
7149**
7150** ^The sqlite3_release_memory() interface attempts to free N bytes
7151** of heap memory by deallocating non-essential memory allocations
7152** held by the database library. Memory used to cache database
7153** pages to improve performance is an example of non-essential memory.
7154** ^sqlite3_release_memory() returns the number of bytes actually freed,
7155** which might be more or less than the amount requested.
7156** ^The sqlite3_release_memory() routine is a no-op returning zero
7157** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
7158**
7159** See also: [sqlite3_db_release_memory()]
7160*/
7161SQLITE_API int sqlite3_release_memory(int);
7162
7163/*
7164** CAPI3REF: Free Memory Used By A Database Connection
7165** METHOD: sqlite3
7166**
7167** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
7168** memory as possible from database connection D. Unlike the
7169** [sqlite3_release_memory()] interface, this interface is in effect even
7170** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
7171** omitted.
7172**
7173** See also: [sqlite3_release_memory()]
7174*/
7175SQLITE_API int sqlite3_db_release_memory(sqlite3*);
7176
7177/*
7178** CAPI3REF: Impose A Limit On Heap Size
7179**
7180** These interfaces impose limits on the amount of heap memory that will be
7181** by all database connections within a single process.
7182**
7183** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
7184** soft limit on the amount of heap memory that may be allocated by SQLite.
7185** ^SQLite strives to keep heap memory utilization below the soft heap
7186** limit by reducing the number of pages held in the page cache
7187** as heap memory usages approaches the limit.
7188** ^The soft heap limit is "soft" because even though SQLite strives to stay
7189** below the limit, it will exceed the limit rather than generate
7190** an [SQLITE_NOMEM] error. In other words, the soft heap limit
7191** is advisory only.
7192**
7193** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of
7194** N bytes on the amount of memory that will be allocated. ^The
7195** sqlite3_hard_heap_limit64(N) interface is similar to
7196** sqlite3_soft_heap_limit64(N) except that memory allocations will fail
7197** when the hard heap limit is reached.
7198**
7199** ^The return value from both sqlite3_soft_heap_limit64() and
7200** sqlite3_hard_heap_limit64() is the size of
7201** the heap limit prior to the call, or negative in the case of an
7202** error. ^If the argument N is negative
7203** then no change is made to the heap limit. Hence, the current
7204** size of heap limits can be determined by invoking
7205** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
7206**
7207** ^Setting the heap limits to zero disables the heap limiter mechanism.
7208**
7209** ^The soft heap limit may not be greater than the hard heap limit.
7210** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
7211** is invoked with a value of N that is greater than the hard heap limit,
7212** the soft heap limit is set to the value of the hard heap limit.
7213** ^The soft heap limit is automatically enabled whenever the hard heap
7214** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
7215** the soft heap limit is outside the range of 1..N, then the soft heap
7216** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the
7217** hard heap limit is enabled makes the soft heap limit equal to the
7218** hard heap limit.
7219**
7220** The memory allocation limits can also be adjusted using
7221** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit].
7222**
7223** ^(The heap limits are not enforced in the current implementation
7224** if one or more of following conditions are true:
7225**
7226** <ul>
7227** <li> The limit value is set to zero.
7228** <li> Memory accounting is disabled using a combination of the
7229** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
7230** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
7231** <li> An alternative page cache implementation is specified using
7232** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
7233** <li> The page cache allocates from its own memory pool supplied
7234** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
7235** from the heap.
7236** </ul>)^
7237**
7238** The circumstances under which SQLite will enforce the heap limits may
7239** changes in future releases of SQLite.
7240*/
7241SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
7242SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N);
7243
7244/*
7245** CAPI3REF: Deprecated Soft Heap Limit Interface
7246** DEPRECATED
7247**
7248** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
7249** interface. This routine is provided for historical compatibility
7250** only. All new applications should use the
7251** [sqlite3_soft_heap_limit64()] interface rather than this one.
7252*/
7253SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
7254
7255
7256/*
7257** CAPI3REF: Extract Metadata About A Column Of A Table
7258** METHOD: sqlite3
7259**
7260** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
7261** information about column C of table T in database D
7262** on [database connection] X.)^ ^The sqlite3_table_column_metadata()
7263** interface returns SQLITE_OK and fills in the non-NULL pointers in
7264** the final five arguments with appropriate values if the specified
7265** column exists. ^The sqlite3_table_column_metadata() interface returns
7266** SQLITE_ERROR if the specified column does not exist.
7267** ^If the column-name parameter to sqlite3_table_column_metadata() is a
7268** NULL pointer, then this routine simply checks for the existence of the
7269** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
7270** does not. If the table name parameter T in a call to
7271** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
7272** undefined behavior.
7273**
7274** ^The column is identified by the second, third and fourth parameters to
7275** this function. ^(The second parameter is either the name of the database
7276** (i.e. "main", "temp", or an attached database) containing the specified
7277** table or NULL.)^ ^If it is NULL, then all attached databases are searched
7278** for the table using the same algorithm used by the database engine to
7279** resolve unqualified table references.
7280**
7281** ^The third and fourth parameters to this function are the table and column
7282** name of the desired column, respectively.
7283**
7284** ^Metadata is returned by writing to the memory locations passed as the 5th
7285** and subsequent parameters to this function. ^Any of these arguments may be
7286** NULL, in which case the corresponding element of metadata is omitted.
7287**
7288** ^(<blockquote>
7289** <table border="1">
7290** <tr><th> Parameter <th> Output<br>Type <th> Description
7291**
7292** <tr><td> 5th <td> const char* <td> Data type
7293** <tr><td> 6th <td> const char* <td> Name of default collation sequence
7294** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
7295** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
7296** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
7297** </table>
7298** </blockquote>)^
7299**
7300** ^The memory pointed to by the character pointers returned for the
7301** declaration type and collation sequence is valid until the next
7302** call to any SQLite API function.
7303**
7304** ^If the specified table is actually a view, an [error code] is returned.
7305**
7306** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
7307** is not a [WITHOUT ROWID] table and an
7308** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
7309** parameters are set for the explicitly declared column. ^(If there is no
7310** [INTEGER PRIMARY KEY] column, then the outputs
7311** for the [rowid] are set as follows:
7312**
7313** <pre>
7314** data type: "INTEGER"
7315** collation sequence: "BINARY"
7316** not null: 0
7317** primary key: 1
7318** auto increment: 0
7319** </pre>)^
7320**
7321** ^This function causes all database schemas to be read from disk and
7322** parsed, if that has not already been done, and returns an error if
7323** any errors are encountered while loading the schema.
7324*/
7325SQLITE_API int sqlite3_table_column_metadata(
7326 sqlite3 *db, /* Connection handle */
7327 const char *zDbName, /* Database name or NULL */
7328 const char *zTableName, /* Table name */
7329 const char *zColumnName, /* Column name */
7330 char const **pzDataType, /* OUTPUT: Declared data type */
7331 char const **pzCollSeq, /* OUTPUT: Collation sequence name */
7332 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
7333 int *pPrimaryKey, /* OUTPUT: True if column part of PK */
7334 int *pAutoinc /* OUTPUT: True if column is auto-increment */
7335);
7336
7337/*
7338** CAPI3REF: Load An Extension
7339** METHOD: sqlite3
7340**
7341** ^This interface loads an SQLite extension library from the named file.
7342**
7343** ^The sqlite3_load_extension() interface attempts to load an
7344** [SQLite extension] library contained in the file zFile. If
7345** the file cannot be loaded directly, attempts are made to load
7346** with various operating-system specific extensions added.
7347** So for example, if "samplelib" cannot be loaded, then names like
7348** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
7349** be tried also.
7350**
7351** ^The entry point is zProc.
7352** ^(zProc may be 0, in which case SQLite will try to come up with an
7353** entry point name on its own. It first tries "sqlite3_extension_init".
7354** If that does not work, it constructs a name "sqlite3_X_init" where the
7355** X is consists of the lower-case equivalent of all ASCII alphabetic
7356** characters in the filename from the last "/" to the first following
7357** "." and omitting any initial "lib".)^
7358** ^The sqlite3_load_extension() interface returns
7359** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
7360** ^If an error occurs and pzErrMsg is not 0, then the
7361** [sqlite3_load_extension()] interface shall attempt to
7362** fill *pzErrMsg with error message text stored in memory
7363** obtained from [sqlite3_malloc()]. The calling function
7364** should free this memory by calling [sqlite3_free()].
7365**
7366** ^Extension loading must be enabled using
7367** [sqlite3_enable_load_extension()] or
7368** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
7369** prior to calling this API,
7370** otherwise an error will be returned.
7371**
7372** <b>Security warning:</b> It is recommended that the
7373** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
7374** interface. The use of the [sqlite3_enable_load_extension()] interface
7375** should be avoided. This will keep the SQL function [load_extension()]
7376** disabled and prevent SQL injections from giving attackers
7377** access to extension loading capabilities.
7378**
7379** See also the [load_extension() SQL function].
7380*/
7381SQLITE_API int sqlite3_load_extension(
7382 sqlite3 *db, /* Load the extension into this database connection */
7383 const char *zFile, /* Name of the shared library containing extension */
7384 const char *zProc, /* Entry point. Derived from zFile if 0 */
7385 char **pzErrMsg /* Put error message here if not 0 */
7386);
7387
7388/*
7389** CAPI3REF: Enable Or Disable Extension Loading
7390** METHOD: sqlite3
7391**
7392** ^So as not to open security holes in older applications that are
7393** unprepared to deal with [extension loading], and as a means of disabling
7394** [extension loading] while evaluating user-entered SQL, the following API
7395** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
7396**
7397** ^Extension loading is off by default.
7398** ^Call the sqlite3_enable_load_extension() routine with onoff==1
7399** to turn extension loading on and call it with onoff==0 to turn
7400** it back off again.
7401**
7402** ^This interface enables or disables both the C-API
7403** [sqlite3_load_extension()] and the SQL function [load_extension()].
7404** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
7405** to enable or disable only the C-API.)^
7406**
7407** <b>Security warning:</b> It is recommended that extension loading
7408** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
7409** rather than this interface, so the [load_extension()] SQL function
7410** remains disabled. This will prevent SQL injections from giving attackers
7411** access to extension loading capabilities.
7412*/
7413SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
7414
7415/*
7416** CAPI3REF: Automatically Load Statically Linked Extensions
7417**
7418** ^This interface causes the xEntryPoint() function to be invoked for
7419** each new [database connection] that is created. The idea here is that
7420** xEntryPoint() is the entry point for a statically linked [SQLite extension]
7421** that is to be automatically loaded into all new database connections.
7422**
7423** ^(Even though the function prototype shows that xEntryPoint() takes
7424** no arguments and returns void, SQLite invokes xEntryPoint() with three
7425** arguments and expects an integer result as if the signature of the
7426** entry point where as follows:
7427**
7428** <blockquote><pre>
7429** &nbsp; int xEntryPoint(
7430** &nbsp; sqlite3 *db,
7431** &nbsp; const char **pzErrMsg,
7432** &nbsp; const struct sqlite3_api_routines *pThunk
7433** &nbsp; );
7434** </pre></blockquote>)^
7435**
7436** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
7437** point to an appropriate error message (obtained from [sqlite3_mprintf()])
7438** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
7439** is NULL before calling the xEntryPoint(). ^SQLite will invoke
7440** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
7441** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
7442** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
7443**
7444** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
7445** on the list of automatic extensions is a harmless no-op. ^No entry point
7446** will be called more than once for each database connection that is opened.
7447**
7448** See also: [sqlite3_reset_auto_extension()]
7449** and [sqlite3_cancel_auto_extension()]
7450*/
7451SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
7452
7453/*
7454** CAPI3REF: Cancel Automatic Extension Loading
7455**
7456** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
7457** initialization routine X that was registered using a prior call to
7458** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
7459** routine returns 1 if initialization routine X was successfully
7460** unregistered and it returns 0 if X was not on the list of initialization
7461** routines.
7462*/
7463SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
7464
7465/*
7466** CAPI3REF: Reset Automatic Extension Loading
7467**
7468** ^This interface disables all automatic extensions previously
7469** registered using [sqlite3_auto_extension()].
7470*/
7471SQLITE_API void sqlite3_reset_auto_extension(void);
7472
7473/*
7474** Structures used by the virtual table interface
7475*/
7476typedef struct sqlite3_vtab sqlite3_vtab;
7477typedef struct sqlite3_index_info sqlite3_index_info;
7478typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
7479typedef struct sqlite3_module sqlite3_module;
7480
7481/*
7482** CAPI3REF: Virtual Table Object
7483** KEYWORDS: sqlite3_module {virtual table module}
7484**
7485** This structure, sometimes called a "virtual table module",
7486** defines the implementation of a [virtual table].
7487** This structure consists mostly of methods for the module.
7488**
7489** ^A virtual table module is created by filling in a persistent
7490** instance of this structure and passing a pointer to that instance
7491** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
7492** ^The registration remains valid until it is replaced by a different
7493** module or until the [database connection] closes. The content
7494** of this structure must not change while it is registered with
7495** any database connection.
7496*/
7497struct sqlite3_module {
7498 int iVersion;
7499 int (*xCreate)(sqlite3*, void *pAux,
7500 int argc, const char *const*argv,
7501 sqlite3_vtab **ppVTab, char**);
7502 int (*xConnect)(sqlite3*, void *pAux,
7503 int argc, const char *const*argv,
7504 sqlite3_vtab **ppVTab, char**);
7505 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
7506 int (*xDisconnect)(sqlite3_vtab *pVTab);
7507 int (*xDestroy)(sqlite3_vtab *pVTab);
7508 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
7509 int (*xClose)(sqlite3_vtab_cursor*);
7510 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
7511 int argc, sqlite3_value **argv);
7512 int (*xNext)(sqlite3_vtab_cursor*);
7513 int (*xEof)(sqlite3_vtab_cursor*);
7514 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
7515 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
7516 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
7517 int (*xBegin)(sqlite3_vtab *pVTab);
7518 int (*xSync)(sqlite3_vtab *pVTab);
7519 int (*xCommit)(sqlite3_vtab *pVTab);
7520 int (*xRollback)(sqlite3_vtab *pVTab);
7521 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
7522 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
7523 void **ppArg);
7524 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
7525 /* The methods above are in version 1 of the sqlite_module object. Those
7526 ** below are for version 2 and greater. */
7527 int (*xSavepoint)(sqlite3_vtab *pVTab, int);
7528 int (*xRelease)(sqlite3_vtab *pVTab, int);
7529 int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
7530 /* The methods above are in versions 1 and 2 of the sqlite_module object.
7531 ** Those below are for version 3 and greater. */
7532 int (*xShadowName)(const char*);
7533};
7534
7535/*
7536** CAPI3REF: Virtual Table Indexing Information
7537** KEYWORDS: sqlite3_index_info
7538**
7539** The sqlite3_index_info structure and its substructures is used as part
7540** of the [virtual table] interface to
7541** pass information into and receive the reply from the [xBestIndex]
7542** method of a [virtual table module]. The fields under **Inputs** are the
7543** inputs to xBestIndex and are read-only. xBestIndex inserts its
7544** results into the **Outputs** fields.
7545**
7546** ^(The aConstraint[] array records WHERE clause constraints of the form:
7547**
7548** <blockquote>column OP expr</blockquote>
7549**
7550** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^ ^(The particular operator is
7551** stored in aConstraint[].op using one of the
7552** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
7553** ^(The index of the column is stored in
7554** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
7555** expr on the right-hand side can be evaluated (and thus the constraint
7556** is usable) and false if it cannot.)^
7557**
7558** ^The optimizer automatically inverts terms of the form "expr OP column"
7559** and makes other simplifications to the WHERE clause in an attempt to
7560** get as many WHERE clause terms into the form shown above as possible.
7561** ^The aConstraint[] array only reports WHERE clause terms that are
7562** relevant to the particular virtual table being queried.
7563**
7564** ^Information about the ORDER BY clause is stored in aOrderBy[].
7565** ^Each term of aOrderBy records a column of the ORDER BY clause.
7566**
7567** The colUsed field indicates which columns of the virtual table may be
7568** required by the current scan. Virtual table columns are numbered from
7569** zero in the order in which they appear within the CREATE TABLE statement
7570** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
7571** the corresponding bit is set within the colUsed mask if the column may be
7572** required by SQLite. If the table has at least 64 columns and any column
7573** to the right of the first 63 is required, then bit 63 of colUsed is also
7574** set. In other words, column iCol may be required if the expression
7575** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
7576** non-zero.
7577**
7578** The [xBestIndex] method must fill aConstraintUsage[] with information
7579** about what parameters to pass to xFilter. ^If argvIndex>0 then
7580** the right-hand side of the corresponding aConstraint[] is evaluated
7581** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
7582** is true, then the constraint is assumed to be fully handled by the
7583** virtual table and might not be checked again by the byte code.)^ ^(The
7584** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
7585** is left in its default setting of false, the constraint will always be
7586** checked separately in byte code. If the omit flag is change to true, then
7587** the constraint may or may not be checked in byte code. In other words,
7588** when the omit flag is true there is no guarantee that the constraint will
7589** not be checked again using byte code.)^
7590**
7591** ^The idxNum and idxStr values are recorded and passed into the
7592** [xFilter] method.
7593** ^[sqlite3_free()] is used to free idxStr if and only if
7594** needToFreeIdxStr is true.
7595**
7596** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
7597** the correct order to satisfy the ORDER BY clause so that no separate
7598** sorting step is required.
7599**
7600** ^The estimatedCost value is an estimate of the cost of a particular
7601** strategy. A cost of N indicates that the cost of the strategy is similar
7602** to a linear scan of an SQLite table with N rows. A cost of log(N)
7603** indicates that the expense of the operation is similar to that of a
7604** binary search on a unique indexed field of an SQLite table with N rows.
7605**
7606** ^The estimatedRows value is an estimate of the number of rows that
7607** will be returned by the strategy.
7608**
7609** The xBestIndex method may optionally populate the idxFlags field with a
7610** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
7611** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
7612** assumes that the strategy may visit at most one row.
7613**
7614** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
7615** SQLite also assumes that if a call to the xUpdate() method is made as
7616** part of the same statement to delete or update a virtual table row and the
7617** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
7618** any database changes. In other words, if the xUpdate() returns
7619** SQLITE_CONSTRAINT, the database contents must be exactly as they were
7620** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
7621** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
7622** the xUpdate method are automatically rolled back by SQLite.
7623**
7624** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
7625** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
7626** If a virtual table extension is
7627** used with an SQLite version earlier than 3.8.2, the results of attempting
7628** to read or write the estimatedRows field are undefined (but are likely
7629** to include crashing the application). The estimatedRows field should
7630** therefore only be used if [sqlite3_libversion_number()] returns a
7631** value greater than or equal to 3008002. Similarly, the idxFlags field
7632** was added for [version 3.9.0] ([dateof:3.9.0]).
7633** It may therefore only be used if
7634** sqlite3_libversion_number() returns a value greater than or equal to
7635** 3009000.
7636*/
7637struct sqlite3_index_info {
7638 /* Inputs */
7639 int nConstraint; /* Number of entries in aConstraint */
7640 struct sqlite3_index_constraint {
7641 int iColumn; /* Column constrained. -1 for ROWID */
7642 unsigned char op; /* Constraint operator */
7643 unsigned char usable; /* True if this constraint is usable */
7644 int iTermOffset; /* Used internally - xBestIndex should ignore */
7645 } *aConstraint; /* Table of WHERE clause constraints */
7646 int nOrderBy; /* Number of terms in the ORDER BY clause */
7647 struct sqlite3_index_orderby {
7648 int iColumn; /* Column number */
7649 unsigned char desc; /* True for DESC. False for ASC. */
7650 } *aOrderBy; /* The ORDER BY clause */
7651 /* Outputs */
7652 struct sqlite3_index_constraint_usage {
7653 int argvIndex; /* if >0, constraint is part of argv to xFilter */
7654 unsigned char omit; /* Do not code a test for this constraint */
7655 } *aConstraintUsage;
7656 int idxNum; /* Number used to identify the index */
7657 char *idxStr; /* String, possibly obtained from sqlite3_malloc */
7658 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
7659 int orderByConsumed; /* True if output is already ordered */
7660 double estimatedCost; /* Estimated cost of using this index */
7661 /* Fields below are only available in SQLite 3.8.2 and later */
7662 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
7663 /* Fields below are only available in SQLite 3.9.0 and later */
7664 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */
7665 /* Fields below are only available in SQLite 3.10.0 and later */
7666 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */
7667};
7668
7669/*
7670** CAPI3REF: Virtual Table Scan Flags
7671**
7672** Virtual table implementations are allowed to set the
7673** [sqlite3_index_info].idxFlags field to some combination of
7674** these bits.
7675*/
7676#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */
7677
7678/*
7679** CAPI3REF: Virtual Table Constraint Operator Codes
7680**
7681** These macros define the allowed values for the
7682** [sqlite3_index_info].aConstraint[].op field. Each value represents
7683** an operator that is part of a constraint term in the WHERE clause of
7684** a query that uses a [virtual table].
7685**
7686** ^The left-hand operand of the operator is given by the corresponding
7687** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand
7688** operand is the rowid.
7689** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET
7690** operators have no left-hand operand, and so for those operators the
7691** corresponding aConstraint[].iColumn is meaningless and should not be
7692** used.
7693**
7694** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through
7695** value 255 are reserved to represent functions that are overloaded
7696** by the [xFindFunction|xFindFunction method] of the virtual table
7697** implementation.
7698**
7699** The right-hand operands for each constraint might be accessible using
7700** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand
7701** operand is only available if it appears as a single constant literal
7702** in the input SQL. If the right-hand operand is another column or an
7703** expression (even a constant expression) or a parameter, then the
7704** sqlite3_vtab_rhs_value() probably will not be able to extract it.
7705** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and
7706** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand
7707** and hence calls to sqlite3_vtab_rhs_value() for those operators will
7708** always return SQLITE_NOTFOUND.
7709**
7710** The collating sequence to be used for comparison can be found using
7711** the [sqlite3_vtab_collation()] interface. For most real-world virtual
7712** tables, the collating sequence of constraints does not matter (for example
7713** because the constraints are numeric) and so the sqlite3_vtab_collation()
7714** interface is not commonly needed.
7715*/
7716#define SQLITE_INDEX_CONSTRAINT_EQ 2
7717#define SQLITE_INDEX_CONSTRAINT_GT 4
7718#define SQLITE_INDEX_CONSTRAINT_LE 8
7719#define SQLITE_INDEX_CONSTRAINT_LT 16
7720#define SQLITE_INDEX_CONSTRAINT_GE 32
7721#define SQLITE_INDEX_CONSTRAINT_MATCH 64
7722#define SQLITE_INDEX_CONSTRAINT_LIKE 65
7723#define SQLITE_INDEX_CONSTRAINT_GLOB 66
7724#define SQLITE_INDEX_CONSTRAINT_REGEXP 67
7725#define SQLITE_INDEX_CONSTRAINT_NE 68
7726#define SQLITE_INDEX_CONSTRAINT_ISNOT 69
7727#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70
7728#define SQLITE_INDEX_CONSTRAINT_ISNULL 71
7729#define SQLITE_INDEX_CONSTRAINT_IS 72
7730#define SQLITE_INDEX_CONSTRAINT_LIMIT 73
7731#define SQLITE_INDEX_CONSTRAINT_OFFSET 74
7732#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150
7733
7734/*
7735** CAPI3REF: Register A Virtual Table Implementation
7736** METHOD: sqlite3
7737**
7738** ^These routines are used to register a new [virtual table module] name.
7739** ^Module names must be registered before
7740** creating a new [virtual table] using the module and before using a
7741** preexisting [virtual table] for the module.
7742**
7743** ^The module name is registered on the [database connection] specified
7744** by the first parameter. ^The name of the module is given by the
7745** second parameter. ^The third parameter is a pointer to
7746** the implementation of the [virtual table module]. ^The fourth
7747** parameter is an arbitrary client data pointer that is passed through
7748** into the [xCreate] and [xConnect] methods of the virtual table module
7749** when a new virtual table is be being created or reinitialized.
7750**
7751** ^The sqlite3_create_module_v2() interface has a fifth parameter which
7752** is a pointer to a destructor for the pClientData. ^SQLite will
7753** invoke the destructor function (if it is not NULL) when SQLite
7754** no longer needs the pClientData pointer. ^The destructor will also
7755** be invoked if the call to sqlite3_create_module_v2() fails.
7756** ^The sqlite3_create_module()
7757** interface is equivalent to sqlite3_create_module_v2() with a NULL
7758** destructor.
7759**
7760** ^If the third parameter (the pointer to the sqlite3_module object) is
7761** NULL then no new module is created and any existing modules with the
7762** same name are dropped.
7763**
7764** See also: [sqlite3_drop_modules()]
7765*/
7766SQLITE_API int sqlite3_create_module(
7767 sqlite3 *db, /* SQLite connection to register module with */
7768 const char *zName, /* Name of the module */
7769 const sqlite3_module *p, /* Methods for the module */
7770 void *pClientData /* Client data for xCreate/xConnect */
7771);
7772SQLITE_API int sqlite3_create_module_v2(
7773 sqlite3 *db, /* SQLite connection to register module with */
7774 const char *zName, /* Name of the module */
7775 const sqlite3_module *p, /* Methods for the module */
7776 void *pClientData, /* Client data for xCreate/xConnect */
7777 void(*xDestroy)(void*) /* Module destructor function */
7778);
7779
7780/*
7781** CAPI3REF: Remove Unnecessary Virtual Table Implementations
7782** METHOD: sqlite3
7783**
7784** ^The sqlite3_drop_modules(D,L) interface removes all virtual
7785** table modules from database connection D except those named on list L.
7786** The L parameter must be either NULL or a pointer to an array of pointers
7787** to strings where the array is terminated by a single NULL pointer.
7788** ^If the L parameter is NULL, then all virtual table modules are removed.
7789**
7790** See also: [sqlite3_create_module()]
7791*/
7792SQLITE_API int sqlite3_drop_modules(
7793 sqlite3 *db, /* Remove modules from this connection */
7794 const char **azKeep /* Except, do not remove the ones named here */
7795);
7796
7797/*
7798** CAPI3REF: Virtual Table Instance Object
7799** KEYWORDS: sqlite3_vtab
7800**
7801** Every [virtual table module] implementation uses a subclass
7802** of this object to describe a particular instance
7803** of the [virtual table]. Each subclass will
7804** be tailored to the specific needs of the module implementation.
7805** The purpose of this superclass is to define certain fields that are
7806** common to all module implementations.
7807**
7808** ^Virtual tables methods can set an error message by assigning a
7809** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
7810** take care that any prior string is freed by a call to [sqlite3_free()]
7811** prior to assigning a new string to zErrMsg. ^After the error message
7812** is delivered up to the client application, the string will be automatically
7813** freed by sqlite3_free() and the zErrMsg field will be zeroed.
7814*/
7815struct sqlite3_vtab {
7816 const sqlite3_module *pModule; /* The module for this virtual table */
7817 int nRef; /* Number of open cursors */
7818 char *zErrMsg; /* Error message from sqlite3_mprintf() */
7819 /* Virtual table implementations will typically add additional fields */
7820};
7821
7822/*
7823** CAPI3REF: Virtual Table Cursor Object
7824** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
7825**
7826** Every [virtual table module] implementation uses a subclass of the
7827** following structure to describe cursors that point into the
7828** [virtual table] and are used
7829** to loop through the virtual table. Cursors are created using the
7830** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
7831** by the [sqlite3_module.xClose | xClose] method. Cursors are used
7832** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
7833** of the module. Each module implementation will define
7834** the content of a cursor structure to suit its own needs.
7835**
7836** This superclass exists in order to define fields of the cursor that
7837** are common to all implementations.
7838*/
7839struct sqlite3_vtab_cursor {
7840 sqlite3_vtab *pVtab; /* Virtual table of this cursor */
7841 /* Virtual table implementations will typically add additional fields */
7842};
7843
7844/*
7845** CAPI3REF: Declare The Schema Of A Virtual Table
7846**
7847** ^The [xCreate] and [xConnect] methods of a
7848** [virtual table module] call this interface
7849** to declare the format (the names and datatypes of the columns) of
7850** the virtual tables they implement.
7851*/
7852SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
7853
7854/*
7855** CAPI3REF: Overload A Function For A Virtual Table
7856** METHOD: sqlite3
7857**
7858** ^(Virtual tables can provide alternative implementations of functions
7859** using the [xFindFunction] method of the [virtual table module].
7860** But global versions of those functions
7861** must exist in order to be overloaded.)^
7862**
7863** ^(This API makes sure a global version of a function with a particular
7864** name and number of parameters exists. If no such function exists
7865** before this API is called, a new function is created.)^ ^The implementation
7866** of the new function always causes an exception to be thrown. So
7867** the new function is not good for anything by itself. Its only
7868** purpose is to be a placeholder function that can be overloaded
7869** by a [virtual table].
7870*/
7871SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
7872
7873/*
7874** CAPI3REF: A Handle To An Open BLOB
7875** KEYWORDS: {BLOB handle} {BLOB handles}
7876**
7877** An instance of this object represents an open BLOB on which
7878** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
7879** ^Objects of this type are created by [sqlite3_blob_open()]
7880** and destroyed by [sqlite3_blob_close()].
7881** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
7882** can be used to read or write small subsections of the BLOB.
7883** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
7884*/
7885typedef struct sqlite3_blob sqlite3_blob;
7886
7887/*
7888** CAPI3REF: Open A BLOB For Incremental I/O
7889** METHOD: sqlite3
7890** CONSTRUCTOR: sqlite3_blob
7891**
7892** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
7893** in row iRow, column zColumn, table zTable in database zDb;
7894** in other words, the same BLOB that would be selected by:
7895**
7896** <pre>
7897** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
7898** </pre>)^
7899**
7900** ^(Parameter zDb is not the filename that contains the database, but
7901** rather the symbolic name of the database. For attached databases, this is
7902** the name that appears after the AS keyword in the [ATTACH] statement.
7903** For the main database file, the database name is "main". For TEMP
7904** tables, the database name is "temp".)^
7905**
7906** ^If the flags parameter is non-zero, then the BLOB is opened for read
7907** and write access. ^If the flags parameter is zero, the BLOB is opened for
7908** read-only access.
7909**
7910** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
7911** in *ppBlob. Otherwise an [error code] is returned and, unless the error
7912** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
7913** the API is not misused, it is always safe to call [sqlite3_blob_close()]
7914** on *ppBlob after this function it returns.
7915**
7916** This function fails with SQLITE_ERROR if any of the following are true:
7917** <ul>
7918** <li> ^(Database zDb does not exist)^,
7919** <li> ^(Table zTable does not exist within database zDb)^,
7920** <li> ^(Table zTable is a WITHOUT ROWID table)^,
7921** <li> ^(Column zColumn does not exist)^,
7922** <li> ^(Row iRow is not present in the table)^,
7923** <li> ^(The specified column of row iRow contains a value that is not
7924** a TEXT or BLOB value)^,
7925** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
7926** constraint and the blob is being opened for read/write access)^,
7927** <li> ^([foreign key constraints | Foreign key constraints] are enabled,
7928** column zColumn is part of a [child key] definition and the blob is
7929** being opened for read/write access)^.
7930** </ul>
7931**
7932** ^Unless it returns SQLITE_MISUSE, this function sets the
7933** [database connection] error code and message accessible via
7934** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
7935**
7936** A BLOB referenced by sqlite3_blob_open() may be read using the
7937** [sqlite3_blob_read()] interface and modified by using
7938** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a
7939** different row of the same table using the [sqlite3_blob_reopen()]
7940** interface. However, the column, table, or database of a [BLOB handle]
7941** cannot be changed after the [BLOB handle] is opened.
7942**
7943** ^(If the row that a BLOB handle points to is modified by an
7944** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
7945** then the BLOB handle is marked as "expired".
7946** This is true if any column of the row is changed, even a column
7947** other than the one the BLOB handle is open on.)^
7948** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
7949** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
7950** ^(Changes written into a BLOB prior to the BLOB expiring are not
7951** rolled back by the expiration of the BLOB. Such changes will eventually
7952** commit if the transaction continues to completion.)^
7953**
7954** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
7955** the opened blob. ^The size of a blob may not be changed by this
7956** interface. Use the [UPDATE] SQL command to change the size of a
7957** blob.
7958**
7959** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
7960** and the built-in [zeroblob] SQL function may be used to create a
7961** zero-filled blob to read or write using the incremental-blob interface.
7962**
7963** To avoid a resource leak, every open [BLOB handle] should eventually
7964** be released by a call to [sqlite3_blob_close()].
7965**
7966** See also: [sqlite3_blob_close()],
7967** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
7968** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
7969*/
7970SQLITE_API int sqlite3_blob_open(
7971 sqlite3*,
7972 const char *zDb,
7973 const char *zTable,
7974 const char *zColumn,
7975 sqlite3_int64 iRow,
7976 int flags,
7977 sqlite3_blob **ppBlob
7978);
7979
7980/*
7981** CAPI3REF: Move a BLOB Handle to a New Row
7982** METHOD: sqlite3_blob
7983**
7984** ^This function is used to move an existing [BLOB handle] so that it points
7985** to a different row of the same database table. ^The new row is identified
7986** by the rowid value passed as the second argument. Only the row can be
7987** changed. ^The database, table and column on which the blob handle is open
7988** remain the same. Moving an existing [BLOB handle] to a new row is
7989** faster than closing the existing handle and opening a new one.
7990**
7991** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
7992** it must exist and there must be either a blob or text value stored in
7993** the nominated column.)^ ^If the new row is not present in the table, or if
7994** it does not contain a blob or text value, or if another error occurs, an
7995** SQLite error code is returned and the blob handle is considered aborted.
7996** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
7997** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
7998** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
7999** always returns zero.
8000**
8001** ^This function sets the database handle error code and message.
8002*/
8003SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
8004
8005/*
8006** CAPI3REF: Close A BLOB Handle
8007** DESTRUCTOR: sqlite3_blob
8008**
8009** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
8010** unconditionally. Even if this routine returns an error code, the
8011** handle is still closed.)^
8012**
8013** ^If the blob handle being closed was opened for read-write access, and if
8014** the database is in auto-commit mode and there are no other open read-write
8015** blob handles or active write statements, the current transaction is
8016** committed. ^If an error occurs while committing the transaction, an error
8017** code is returned and the transaction rolled back.
8018**
8019** Calling this function with an argument that is not a NULL pointer or an
8020** open blob handle results in undefined behaviour. ^Calling this routine
8021** with a null pointer (such as would be returned by a failed call to
8022** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
8023** is passed a valid open blob handle, the values returned by the
8024** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
8025*/
8026SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
8027
8028/*
8029** CAPI3REF: Return The Size Of An Open BLOB
8030** METHOD: sqlite3_blob
8031**
8032** ^Returns the size in bytes of the BLOB accessible via the
8033** successfully opened [BLOB handle] in its only argument. ^The
8034** incremental blob I/O routines can only read or overwriting existing
8035** blob content; they cannot change the size of a blob.
8036**
8037** This routine only works on a [BLOB handle] which has been created
8038** by a prior successful call to [sqlite3_blob_open()] and which has not
8039** been closed by [sqlite3_blob_close()]. Passing any other pointer in
8040** to this routine results in undefined and probably undesirable behavior.
8041*/
8042SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
8043
8044/*
8045** CAPI3REF: Read Data From A BLOB Incrementally
8046** METHOD: sqlite3_blob
8047**
8048** ^(This function is used to read data from an open [BLOB handle] into a
8049** caller-supplied buffer. N bytes of data are copied into buffer Z
8050** from the open BLOB, starting at offset iOffset.)^
8051**
8052** ^If offset iOffset is less than N bytes from the end of the BLOB,
8053** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
8054** less than zero, [SQLITE_ERROR] is returned and no data is read.
8055** ^The size of the blob (and hence the maximum value of N+iOffset)
8056** can be determined using the [sqlite3_blob_bytes()] interface.
8057**
8058** ^An attempt to read from an expired [BLOB handle] fails with an
8059** error code of [SQLITE_ABORT].
8060**
8061** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
8062** Otherwise, an [error code] or an [extended error code] is returned.)^
8063**
8064** This routine only works on a [BLOB handle] which has been created
8065** by a prior successful call to [sqlite3_blob_open()] and which has not
8066** been closed by [sqlite3_blob_close()]. Passing any other pointer in
8067** to this routine results in undefined and probably undesirable behavior.
8068**
8069** See also: [sqlite3_blob_write()].
8070*/
8071SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
8072
8073/*
8074** CAPI3REF: Write Data Into A BLOB Incrementally
8075** METHOD: sqlite3_blob
8076**
8077** ^(This function is used to write data into an open [BLOB handle] from a
8078** caller-supplied buffer. N bytes of data are copied from the buffer Z
8079** into the open BLOB, starting at offset iOffset.)^
8080**
8081** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
8082** Otherwise, an [error code] or an [extended error code] is returned.)^
8083** ^Unless SQLITE_MISUSE is returned, this function sets the
8084** [database connection] error code and message accessible via
8085** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
8086**
8087** ^If the [BLOB handle] passed as the first argument was not opened for
8088** writing (the flags parameter to [sqlite3_blob_open()] was zero),
8089** this function returns [SQLITE_READONLY].
8090**
8091** This function may only modify the contents of the BLOB; it is
8092** not possible to increase the size of a BLOB using this API.
8093** ^If offset iOffset is less than N bytes from the end of the BLOB,
8094** [SQLITE_ERROR] is returned and no data is written. The size of the
8095** BLOB (and hence the maximum value of N+iOffset) can be determined
8096** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
8097** than zero [SQLITE_ERROR] is returned and no data is written.
8098**
8099** ^An attempt to write to an expired [BLOB handle] fails with an
8100** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
8101** before the [BLOB handle] expired are not rolled back by the
8102** expiration of the handle, though of course those changes might
8103** have been overwritten by the statement that expired the BLOB handle
8104** or by other independent statements.
8105**
8106** This routine only works on a [BLOB handle] which has been created
8107** by a prior successful call to [sqlite3_blob_open()] and which has not
8108** been closed by [sqlite3_blob_close()]. Passing any other pointer in
8109** to this routine results in undefined and probably undesirable behavior.
8110**
8111** See also: [sqlite3_blob_read()].
8112*/
8113SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
8114
8115/*
8116** CAPI3REF: Virtual File System Objects
8117**
8118** A virtual filesystem (VFS) is an [sqlite3_vfs] object
8119** that SQLite uses to interact
8120** with the underlying operating system. Most SQLite builds come with a
8121** single default VFS that is appropriate for the host computer.
8122** New VFSes can be registered and existing VFSes can be unregistered.
8123** The following interfaces are provided.
8124**
8125** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
8126** ^Names are case sensitive.
8127** ^Names are zero-terminated UTF-8 strings.
8128** ^If there is no match, a NULL pointer is returned.
8129** ^If zVfsName is NULL then the default VFS is returned.
8130**
8131** ^New VFSes are registered with sqlite3_vfs_register().
8132** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
8133** ^The same VFS can be registered multiple times without injury.
8134** ^To make an existing VFS into the default VFS, register it again
8135** with the makeDflt flag set. If two different VFSes with the
8136** same name are registered, the behavior is undefined. If a
8137** VFS is registered with a name that is NULL or an empty string,
8138** then the behavior is undefined.
8139**
8140** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
8141** ^(If the default VFS is unregistered, another VFS is chosen as
8142** the default. The choice for the new VFS is arbitrary.)^
8143*/
8144SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
8145SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
8146SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
8147
8148/*
8149** CAPI3REF: Mutexes
8150**
8151** The SQLite core uses these routines for thread
8152** synchronization. Though they are intended for internal
8153** use by SQLite, code that links against SQLite is
8154** permitted to use any of these routines.
8155**
8156** The SQLite source code contains multiple implementations
8157** of these mutex routines. An appropriate implementation
8158** is selected automatically at compile-time. The following
8159** implementations are available in the SQLite core:
8160**
8161** <ul>
8162** <li> SQLITE_MUTEX_PTHREADS
8163** <li> SQLITE_MUTEX_W32
8164** <li> SQLITE_MUTEX_NOOP
8165** </ul>
8166**
8167** The SQLITE_MUTEX_NOOP implementation is a set of routines
8168** that does no real locking and is appropriate for use in
8169** a single-threaded application. The SQLITE_MUTEX_PTHREADS and
8170** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
8171** and Windows.
8172**
8173** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
8174** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
8175** implementation is included with the library. In this case the
8176** application must supply a custom mutex implementation using the
8177** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
8178** before calling sqlite3_initialize() or any other public sqlite3_
8179** function that calls sqlite3_initialize().
8180**
8181** ^The sqlite3_mutex_alloc() routine allocates a new
8182** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
8183** routine returns NULL if it is unable to allocate the requested
8184** mutex. The argument to sqlite3_mutex_alloc() must one of these
8185** integer constants:
8186**
8187** <ul>
8188** <li> SQLITE_MUTEX_FAST
8189** <li> SQLITE_MUTEX_RECURSIVE
8190** <li> SQLITE_MUTEX_STATIC_MAIN
8191** <li> SQLITE_MUTEX_STATIC_MEM
8192** <li> SQLITE_MUTEX_STATIC_OPEN
8193** <li> SQLITE_MUTEX_STATIC_PRNG
8194** <li> SQLITE_MUTEX_STATIC_LRU
8195** <li> SQLITE_MUTEX_STATIC_PMEM
8196** <li> SQLITE_MUTEX_STATIC_APP1
8197** <li> SQLITE_MUTEX_STATIC_APP2
8198** <li> SQLITE_MUTEX_STATIC_APP3
8199** <li> SQLITE_MUTEX_STATIC_VFS1
8200** <li> SQLITE_MUTEX_STATIC_VFS2
8201** <li> SQLITE_MUTEX_STATIC_VFS3
8202** </ul>
8203**
8204** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
8205** cause sqlite3_mutex_alloc() to create
8206** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
8207** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
8208** The mutex implementation does not need to make a distinction
8209** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
8210** not want to. SQLite will only request a recursive mutex in
8211** cases where it really needs one. If a faster non-recursive mutex
8212** implementation is available on the host platform, the mutex subsystem
8213** might return such a mutex in response to SQLITE_MUTEX_FAST.
8214**
8215** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
8216** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
8217** a pointer to a static preexisting mutex. ^Nine static mutexes are
8218** used by the current version of SQLite. Future versions of SQLite
8219** may add additional static mutexes. Static mutexes are for internal
8220** use by SQLite only. Applications that use SQLite mutexes should
8221** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
8222** SQLITE_MUTEX_RECURSIVE.
8223**
8224** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
8225** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
8226** returns a different mutex on every call. ^For the static
8227** mutex types, the same mutex is returned on every call that has
8228** the same type number.
8229**
8230** ^The sqlite3_mutex_free() routine deallocates a previously
8231** allocated dynamic mutex. Attempting to deallocate a static
8232** mutex results in undefined behavior.
8233**
8234** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
8235** to enter a mutex. ^If another thread is already within the mutex,
8236** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
8237** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
8238** upon successful entry. ^(Mutexes created using
8239** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
8240** In such cases, the
8241** mutex must be exited an equal number of times before another thread
8242** can enter.)^ If the same thread tries to enter any mutex other
8243** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
8244**
8245** ^(Some systems (for example, Windows 95) do not support the operation
8246** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
8247** will always return SQLITE_BUSY. The SQLite core only ever uses
8248** sqlite3_mutex_try() as an optimization so this is acceptable
8249** behavior.)^
8250**
8251** ^The sqlite3_mutex_leave() routine exits a mutex that was
8252** previously entered by the same thread. The behavior
8253** is undefined if the mutex is not currently entered by the
8254** calling thread or is not currently allocated.
8255**
8256** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(),
8257** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer,
8258** then any of the four routines behaves as a no-op.
8259**
8260** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
8261*/
8262SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
8263SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
8264SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
8265SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
8266SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
8267
8268/*
8269** CAPI3REF: Mutex Methods Object
8270**
8271** An instance of this structure defines the low-level routines
8272** used to allocate and use mutexes.
8273**
8274** Usually, the default mutex implementations provided by SQLite are
8275** sufficient, however the application has the option of substituting a custom
8276** implementation for specialized deployments or systems for which SQLite
8277** does not provide a suitable implementation. In this case, the application
8278** creates and populates an instance of this structure to pass
8279** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
8280** Additionally, an instance of this structure can be used as an
8281** output variable when querying the system for the current mutex
8282** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
8283**
8284** ^The xMutexInit method defined by this structure is invoked as
8285** part of system initialization by the sqlite3_initialize() function.
8286** ^The xMutexInit routine is called by SQLite exactly once for each
8287** effective call to [sqlite3_initialize()].
8288**
8289** ^The xMutexEnd method defined by this structure is invoked as
8290** part of system shutdown by the sqlite3_shutdown() function. The
8291** implementation of this method is expected to release all outstanding
8292** resources obtained by the mutex methods implementation, especially
8293** those obtained by the xMutexInit method. ^The xMutexEnd()
8294** interface is invoked exactly once for each call to [sqlite3_shutdown()].
8295**
8296** ^(The remaining seven methods defined by this structure (xMutexAlloc,
8297** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
8298** xMutexNotheld) implement the following interfaces (respectively):
8299**
8300** <ul>
8301** <li> [sqlite3_mutex_alloc()] </li>
8302** <li> [sqlite3_mutex_free()] </li>
8303** <li> [sqlite3_mutex_enter()] </li>
8304** <li> [sqlite3_mutex_try()] </li>
8305** <li> [sqlite3_mutex_leave()] </li>
8306** <li> [sqlite3_mutex_held()] </li>
8307** <li> [sqlite3_mutex_notheld()] </li>
8308** </ul>)^
8309**
8310** The only difference is that the public sqlite3_XXX functions enumerated
8311** above silently ignore any invocations that pass a NULL pointer instead
8312** of a valid mutex handle. The implementations of the methods defined
8313** by this structure are not required to handle this case. The results
8314** of passing a NULL pointer instead of a valid mutex handle are undefined
8315** (i.e. it is acceptable to provide an implementation that segfaults if
8316** it is passed a NULL pointer).
8317**
8318** The xMutexInit() method must be threadsafe. It must be harmless to
8319** invoke xMutexInit() multiple times within the same process and without
8320** intervening calls to xMutexEnd(). Second and subsequent calls to
8321** xMutexInit() must be no-ops.
8322**
8323** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
8324** and its associates). Similarly, xMutexAlloc() must not use SQLite memory
8325** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
8326** memory allocation for a fast or recursive mutex.
8327**
8328** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
8329** called, but only if the prior call to xMutexInit returned SQLITE_OK.
8330** If xMutexInit fails in any way, it is expected to clean up after itself
8331** prior to returning.
8332*/
8333typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
8334struct sqlite3_mutex_methods {
8335 int (*xMutexInit)(void);
8336 int (*xMutexEnd)(void);
8337 sqlite3_mutex *(*xMutexAlloc)(int);
8338 void (*xMutexFree)(sqlite3_mutex *);
8339 void (*xMutexEnter)(sqlite3_mutex *);
8340 int (*xMutexTry)(sqlite3_mutex *);
8341 void (*xMutexLeave)(sqlite3_mutex *);
8342 int (*xMutexHeld)(sqlite3_mutex *);
8343 int (*xMutexNotheld)(sqlite3_mutex *);
8344};
8345
8346/*
8347** CAPI3REF: Mutex Verification Routines
8348**
8349** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
8350** are intended for use inside assert() statements. The SQLite core
8351** never uses these routines except inside an assert() and applications
8352** are advised to follow the lead of the core. The SQLite core only
8353** provides implementations for these routines when it is compiled
8354** with the SQLITE_DEBUG flag. External mutex implementations
8355** are only required to provide these routines if SQLITE_DEBUG is
8356** defined and if NDEBUG is not defined.
8357**
8358** These routines should return true if the mutex in their argument
8359** is held or not held, respectively, by the calling thread.
8360**
8361** The implementation is not required to provide versions of these
8362** routines that actually work. If the implementation does not provide working
8363** versions of these routines, it should at least provide stubs that always
8364** return true so that one does not get spurious assertion failures.
8365**
8366** If the argument to sqlite3_mutex_held() is a NULL pointer then
8367** the routine should return 1. This seems counter-intuitive since
8368** clearly the mutex cannot be held if it does not exist. But
8369** the reason the mutex does not exist is because the build is not
8370** using mutexes. And we do not want the assert() containing the
8371** call to sqlite3_mutex_held() to fail, so a non-zero return is
8372** the appropriate thing to do. The sqlite3_mutex_notheld()
8373** interface should also return 1 when given a NULL pointer.
8374*/
8375#ifndef NDEBUG
8376SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
8377SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
8378#endif
8379
8380/*
8381** CAPI3REF: Mutex Types
8382**
8383** The [sqlite3_mutex_alloc()] interface takes a single argument
8384** which is one of these integer constants.
8385**
8386** The set of static mutexes may change from one SQLite release to the
8387** next. Applications that override the built-in mutex logic must be
8388** prepared to accommodate additional static mutexes.
8389*/
8390#define SQLITE_MUTEX_FAST 0
8391#define SQLITE_MUTEX_RECURSIVE 1
8392#define SQLITE_MUTEX_STATIC_MAIN 2
8393#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
8394#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
8395#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
8396#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */
8397#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
8398#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
8399#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
8400#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */
8401#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */
8402#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */
8403#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */
8404#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */
8405#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */
8406
8407/* Legacy compatibility: */
8408#define SQLITE_MUTEX_STATIC_MASTER 2
8409
8410
8411/*
8412** CAPI3REF: Retrieve the mutex for a database connection
8413** METHOD: sqlite3
8414**
8415** ^This interface returns a pointer the [sqlite3_mutex] object that
8416** serializes access to the [database connection] given in the argument
8417** when the [threading mode] is Serialized.
8418** ^If the [threading mode] is Single-thread or Multi-thread then this
8419** routine returns a NULL pointer.
8420*/
8421SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
8422
8423/*
8424** CAPI3REF: Low-Level Control Of Database Files
8425** METHOD: sqlite3
8426** KEYWORDS: {file control}
8427**
8428** ^The [sqlite3_file_control()] interface makes a direct call to the
8429** xFileControl method for the [sqlite3_io_methods] object associated
8430** with a particular database identified by the second argument. ^The
8431** name of the database is "main" for the main database or "temp" for the
8432** TEMP database, or the name that appears after the AS keyword for
8433** databases that are added using the [ATTACH] SQL command.
8434** ^A NULL pointer can be used in place of "main" to refer to the
8435** main database file.
8436** ^The third and fourth parameters to this routine
8437** are passed directly through to the second and third parameters of
8438** the xFileControl method. ^The return value of the xFileControl
8439** method becomes the return value of this routine.
8440**
8441** A few opcodes for [sqlite3_file_control()] are handled directly
8442** by the SQLite core and never invoke the
8443** sqlite3_io_methods.xFileControl method.
8444** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
8445** a pointer to the underlying [sqlite3_file] object to be written into
8446** the space pointed to by the 4th parameter. The
8447** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
8448** the [sqlite3_file] object associated with the journal file instead of
8449** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns
8450** a pointer to the underlying [sqlite3_vfs] object for the file.
8451** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
8452** from the pager.
8453**
8454** ^If the second parameter (zDbName) does not match the name of any
8455** open database file, then SQLITE_ERROR is returned. ^This error
8456** code is not remembered and will not be recalled by [sqlite3_errcode()]
8457** or [sqlite3_errmsg()]. The underlying xFileControl method might
8458** also return SQLITE_ERROR. There is no way to distinguish between
8459** an incorrect zDbName and an SQLITE_ERROR return from the underlying
8460** xFileControl method.
8461**
8462** See also: [file control opcodes]
8463*/
8464SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
8465
8466/*
8467** CAPI3REF: Testing Interface
8468**
8469** ^The sqlite3_test_control() interface is used to read out internal
8470** state of SQLite and to inject faults into SQLite for testing
8471** purposes. ^The first parameter is an operation code that determines
8472** the number, meaning, and operation of all subsequent parameters.
8473**
8474** This interface is not for use by applications. It exists solely
8475** for verifying the correct operation of the SQLite library. Depending
8476** on how the SQLite library is compiled, this interface might not exist.
8477**
8478** The details of the operation codes, their meanings, the parameters
8479** they take, and what they do are all subject to change without notice.
8480** Unlike most of the SQLite API, this function is not guaranteed to
8481** operate consistently from one release to the next.
8482*/
8483SQLITE_API int sqlite3_test_control(int op, ...);
8484
8485/*
8486** CAPI3REF: Testing Interface Operation Codes
8487**
8488** These constants are the valid operation code parameters used
8489** as the first argument to [sqlite3_test_control()].
8490**
8491** These parameters and their meanings are subject to change
8492** without notice. These values are for testing purposes only.
8493** Applications should not use any of these parameters or the
8494** [sqlite3_test_control()] interface.
8495*/
8496#define SQLITE_TESTCTRL_FIRST 5
8497#define SQLITE_TESTCTRL_PRNG_SAVE 5
8498#define SQLITE_TESTCTRL_PRNG_RESTORE 6
8499#define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */
8500#define SQLITE_TESTCTRL_BITVEC_TEST 8
8501#define SQLITE_TESTCTRL_FAULT_INSTALL 9
8502#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
8503#define SQLITE_TESTCTRL_PENDING_BYTE 11
8504#define SQLITE_TESTCTRL_ASSERT 12
8505#define SQLITE_TESTCTRL_ALWAYS 13
8506#define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */
8507#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
8508#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */
8509#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */
8510#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17
8511#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
8512#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */
8513#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19
8514#define SQLITE_TESTCTRL_NEVER_CORRUPT 20
8515#define SQLITE_TESTCTRL_VDBE_COVERAGE 21
8516#define SQLITE_TESTCTRL_BYTEORDER 22
8517#define SQLITE_TESTCTRL_ISINIT 23
8518#define SQLITE_TESTCTRL_SORTER_MMAP 24
8519#define SQLITE_TESTCTRL_IMPOSTER 25
8520#define SQLITE_TESTCTRL_PARSER_COVERAGE 26
8521#define SQLITE_TESTCTRL_RESULT_INTREAL 27
8522#define SQLITE_TESTCTRL_PRNG_SEED 28
8523#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29
8524#define SQLITE_TESTCTRL_SEEK_COUNT 30
8525#define SQLITE_TESTCTRL_TRACEFLAGS 31
8526#define SQLITE_TESTCTRL_TUNE 32
8527#define SQLITE_TESTCTRL_LOGEST 33
8528#define SQLITE_TESTCTRL_USELONGDOUBLE 34
8529#define SQLITE_TESTCTRL_LAST 34 /* Largest TESTCTRL */
8530
8531/*
8532** CAPI3REF: SQL Keyword Checking
8533**
8534** These routines provide access to the set of SQL language keywords
8535** recognized by SQLite. Applications can uses these routines to determine
8536** whether or not a specific identifier needs to be escaped (for example,
8537** by enclosing in double-quotes) so as not to confuse the parser.
8538**
8539** The sqlite3_keyword_count() interface returns the number of distinct
8540** keywords understood by SQLite.
8541**
8542** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and
8543** makes *Z point to that keyword expressed as UTF8 and writes the number
8544** of bytes in the keyword into *L. The string that *Z points to is not
8545** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns
8546** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
8547** or L are NULL or invalid pointers then calls to
8548** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
8549**
8550** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
8551** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
8552** if it is and zero if not.
8553**
8554** The parser used by SQLite is forgiving. It is often possible to use
8555** a keyword as an identifier as long as such use does not result in a
8556** parsing ambiguity. For example, the statement
8557** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
8558** creates a new table named "BEGIN" with three columns named
8559** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid
8560** using keywords as identifiers. Common techniques used to avoid keyword
8561** name collisions include:
8562** <ul>
8563** <li> Put all identifier names inside double-quotes. This is the official
8564** SQL way to escape identifier names.
8565** <li> Put identifier names inside &#91;...&#93;. This is not standard SQL,
8566** but it is what SQL Server does and so lots of programmers use this
8567** technique.
8568** <li> Begin every identifier with the letter "Z" as no SQL keywords start
8569** with "Z".
8570** <li> Include a digit somewhere in every identifier name.
8571** </ul>
8572**
8573** Note that the number of keywords understood by SQLite can depend on
8574** compile-time options. For example, "VACUUM" is not a keyword if
8575** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also,
8576** new keywords may be added to future releases of SQLite.
8577*/
8578SQLITE_API int sqlite3_keyword_count(void);
8579SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
8580SQLITE_API int sqlite3_keyword_check(const char*,int);
8581
8582/*
8583** CAPI3REF: Dynamic String Object
8584** KEYWORDS: {dynamic string}
8585**
8586** An instance of the sqlite3_str object contains a dynamically-sized
8587** string under construction.
8588**
8589** The lifecycle of an sqlite3_str object is as follows:
8590** <ol>
8591** <li> ^The sqlite3_str object is created using [sqlite3_str_new()].
8592** <li> ^Text is appended to the sqlite3_str object using various
8593** methods, such as [sqlite3_str_appendf()].
8594** <li> ^The sqlite3_str object is destroyed and the string it created
8595** is returned using the [sqlite3_str_finish()] interface.
8596** </ol>
8597*/
8598typedef struct sqlite3_str sqlite3_str;
8599
8600/*
8601** CAPI3REF: Create A New Dynamic String Object
8602** CONSTRUCTOR: sqlite3_str
8603**
8604** ^The [sqlite3_str_new(D)] interface allocates and initializes
8605** a new [sqlite3_str] object. To avoid memory leaks, the object returned by
8606** [sqlite3_str_new()] must be freed by a subsequent call to
8607** [sqlite3_str_finish(X)].
8608**
8609** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
8610** valid [sqlite3_str] object, though in the event of an out-of-memory
8611** error the returned object might be a special singleton that will
8612** silently reject new text, always return SQLITE_NOMEM from
8613** [sqlite3_str_errcode()], always return 0 for
8614** [sqlite3_str_length()], and always return NULL from
8615** [sqlite3_str_finish(X)]. It is always safe to use the value
8616** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
8617** to any of the other [sqlite3_str] methods.
8618**
8619** The D parameter to [sqlite3_str_new(D)] may be NULL. If the
8620** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
8621** length of the string contained in the [sqlite3_str] object will be
8622** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
8623** of [SQLITE_MAX_LENGTH].
8624*/
8625SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
8626
8627/*
8628** CAPI3REF: Finalize A Dynamic String
8629** DESTRUCTOR: sqlite3_str
8630**
8631** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
8632** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
8633** that contains the constructed string. The calling application should
8634** pass the returned value to [sqlite3_free()] to avoid a memory leak.
8635** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
8636** errors were encountered during construction of the string. ^The
8637** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the
8638** string in [sqlite3_str] object X is zero bytes long.
8639*/
8640SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
8641
8642/*
8643** CAPI3REF: Add Content To A Dynamic String
8644** METHOD: sqlite3_str
8645**
8646** These interfaces add content to an sqlite3_str object previously obtained
8647** from [sqlite3_str_new()].
8648**
8649** ^The [sqlite3_str_appendf(X,F,...)] and
8650** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
8651** functionality of SQLite to append formatted text onto the end of
8652** [sqlite3_str] object X.
8653**
8654** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
8655** onto the end of the [sqlite3_str] object X. N must be non-negative.
8656** S must contain at least N non-zero bytes of content. To append a
8657** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
8658** method instead.
8659**
8660** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
8661** zero-terminated string S onto the end of [sqlite3_str] object X.
8662**
8663** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
8664** single-byte character C onto the end of [sqlite3_str] object X.
8665** ^This method can be used, for example, to add whitespace indentation.
8666**
8667** ^The [sqlite3_str_reset(X)] method resets the string under construction
8668** inside [sqlite3_str] object X back to zero bytes in length.
8669**
8670** These methods do not return a result code. ^If an error occurs, that fact
8671** is recorded in the [sqlite3_str] object and can be recovered by a
8672** subsequent call to [sqlite3_str_errcode(X)].
8673*/
8674SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
8675SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const</