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drh75897232000-05-29 14:26:00 +00001/*
drhb19a2bc2001-09-16 00:13:26 +00002** 2001 September 15
drh75897232000-05-29 14:26:00 +00003**
drhb19a2bc2001-09-16 00:13:26 +00004** The author disclaims copyright to this source code. In place of
5** a legal notice, here is a blessing:
drh75897232000-05-29 14:26:00 +00006**
drhb19a2bc2001-09-16 00:13:26 +00007** May you do good and not evil.
8** May you find forgiveness for yourself and forgive others.
9** May you share freely, never taking more than you give.
drh75897232000-05-29 14:26:00 +000010**
11*************************************************************************
drhb19a2bc2001-09-16 00:13:26 +000012** This header file defines the interface that the SQLite library
drh6ed48bf2007-06-14 20:57:18 +000013** presents to client programs. If a C-function, structure, datatype,
14** or constant definition does not appear in this file, then it is
15** not a published API of SQLite, is subject to change without
16** notice, and should not be referenced by programs that use SQLite.
drh75897232000-05-29 14:26:00 +000017**
drh6ed48bf2007-06-14 20:57:18 +000018** Some of the definitions that are in this file are marked as
19** "experimental". Experimental interfaces are normally new
mihailima3f64902008-06-21 13:35:56 +000020** features recently added to SQLite. We do not anticipate changes
shane7c7c3112009-08-17 15:31:23 +000021** to experimental interfaces but reserve the right to make minor changes
22** if experience from use "in the wild" suggest such changes are prudent.
drh6ed48bf2007-06-14 20:57:18 +000023**
24** The official C-language API documentation for SQLite is derived
25** from comments in this file. This file is the authoritative source
26** on how SQLite interfaces are suppose to operate.
27**
28** The name of this file under configuration management is "sqlite.h.in".
29** The makefile makes some minor changes to this file (such as inserting
30** the version number) and changes its name to "sqlite3.h" as
31** part of the build process.
drh75897232000-05-29 14:26:00 +000032*/
drh12057d52004-09-06 17:34:12 +000033#ifndef _SQLITE3_H_
34#define _SQLITE3_H_
drha18c5682000-10-08 22:20:57 +000035#include <stdarg.h> /* Needed for the definition of va_list */
drh75897232000-05-29 14:26:00 +000036
37/*
drh382c0242001-10-06 16:33:02 +000038** Make sure we can call this stuff from C++.
39*/
40#ifdef __cplusplus
41extern "C" {
42#endif
43
drh6d2069d2007-08-14 01:58:53 +000044
drh382c0242001-10-06 16:33:02 +000045/*
drh73be5012007-08-08 12:11:21 +000046** Add the ability to override 'extern'
47*/
48#ifndef SQLITE_EXTERN
49# define SQLITE_EXTERN extern
50#endif
51
52/*
drh4d6618f2008-09-22 17:54:46 +000053** These no-op macros are used in front of interfaces to mark those
54** interfaces as either deprecated or experimental. New applications
shane7c7c3112009-08-17 15:31:23 +000055** should not use deprecated interfaces - they are support for backwards
drh4d6618f2008-09-22 17:54:46 +000056** compatibility only. Application writers should be aware that
57** experimental interfaces are subject to change in point releases.
58**
59** These macros used to resolve to various kinds of compiler magic that
60** would generate warning messages when they were used. But that
61** compiler magic ended up generating such a flurry of bug reports
62** that we have taken it all out and gone back to using simple
63** noop macros.
shanea79c3cc2008-08-11 17:27:01 +000064*/
drh4d6618f2008-09-22 17:54:46 +000065#define SQLITE_DEPRECATED
66#define SQLITE_EXPERIMENTAL
shanea79c3cc2008-08-11 17:27:01 +000067
68/*
mihailim362cc832008-06-21 06:16:42 +000069** Ensure these symbols were not defined by some previous header file.
drhb86ccfb2003-01-28 23:13:10 +000070*/
drh1e284f42004-10-06 15:52:01 +000071#ifdef SQLITE_VERSION
72# undef SQLITE_VERSION
drh1e284f42004-10-06 15:52:01 +000073#endif
drh6ed48bf2007-06-14 20:57:18 +000074#ifdef SQLITE_VERSION_NUMBER
75# undef SQLITE_VERSION_NUMBER
76#endif
danielk197799ba19e2005-02-05 07:33:34 +000077
78/*
drhb25f9d82008-07-23 15:40:06 +000079** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
drh6ed48bf2007-06-14 20:57:18 +000080**
drh33c1be32008-01-30 16:16:14 +000081** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
82** the sqlite3.h file specify the version of SQLite with which
83** that header file is associated.
danielk197799ba19e2005-02-05 07:33:34 +000084**
drh4e0b31c2009-09-02 19:04:24 +000085** The "version" of SQLite is a string of the form "W.X.Y" or "W.X.Y.Z".
86** The W value is major version number and is always 3 in SQLite3.
87** The W value only changes when backwards compatibility is
mihailim362cc832008-06-21 06:16:42 +000088** broken and we intend to never break backwards compatibility.
drh4e0b31c2009-09-02 19:04:24 +000089** The X value is the minor version number and only changes when
drh6ed48bf2007-06-14 20:57:18 +000090** there are major feature enhancements that are forwards compatible
mihailim362cc832008-06-21 06:16:42 +000091** but not backwards compatible.
drh4e0b31c2009-09-02 19:04:24 +000092** The Y value is the release number and is incremented with
93** each release but resets back to 0 whenever X is incremented.
94** The Z value only appears on branch releases.
drh6ed48bf2007-06-14 20:57:18 +000095**
drh6aa5f152009-08-19 15:57:07 +000096** The SQLITE_VERSION_NUMBER is an integer that is computed as
97** follows:
98**
99** <blockquote><pre>
drh4e0b31c2009-09-02 19:04:24 +0000100** SQLITE_VERSION_NUMBER = W*1000000 + X*1000 + Y
drh6aa5f152009-08-19 15:57:07 +0000101** </pre></blockquote>
102**
drh47baebc2009-08-14 16:01:24 +0000103** Since version 3.6.18, SQLite source code has been stored in the
drh6aa5f152009-08-19 15:57:07 +0000104** <a href="http://www.fossil-scm.org/">fossil configuration management
105** system</a>. The SQLITE_SOURCE_ID
drh47baebc2009-08-14 16:01:24 +0000106** macro is a string which identifies a particular check-in of SQLite
107** within its configuration management system. The string contains the
108** date and time of the check-in (UTC) and an SHA1 hash of the entire
109** source tree.
110**
drh6aa5f152009-08-19 15:57:07 +0000111** See also: [sqlite3_libversion()],
drh4e0b31c2009-09-02 19:04:24 +0000112** [sqlite3_libversion_number()], [sqlite3_sourceid()],
113** [sqlite_version()] and [sqlite_source_id()].
drh33c1be32008-01-30 16:16:14 +0000114**
drh8b39db12009-02-18 18:37:58 +0000115** Requirements: [H10011] [H10014]
danielk197799ba19e2005-02-05 07:33:34 +0000116*/
drh47baebc2009-08-14 16:01:24 +0000117#define SQLITE_VERSION "--VERS--"
118#define SQLITE_VERSION_NUMBER --VERSION-NUMBER--
119#define SQLITE_SOURCE_ID "--SOURCE-ID--"
drhb86ccfb2003-01-28 23:13:10 +0000120
121/*
drh9a247912008-07-22 18:45:08 +0000122** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
drh33c1be32008-01-30 16:16:14 +0000123** KEYWORDS: sqlite3_version
drh6ed48bf2007-06-14 20:57:18 +0000124**
drh47baebc2009-08-14 16:01:24 +0000125** These interfaces provide the same information as the [SQLITE_VERSION],
126** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] #defines in the header,
127** but are associated with the library instead of the header file. Cautious
drh4e0b31c2009-09-02 19:04:24 +0000128** programmers might include assert() statements in their application to
129** verify that values returned by these interfaces match the macros in
130** the header, and thus insure that the application is
drh6aa5f152009-08-19 15:57:07 +0000131** compiled with matching library and header files.
132**
133** <blockquote><pre>
134** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
drh4e0b31c2009-09-02 19:04:24 +0000135** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
136** assert( strcmp(sqlite3_libversion,SQLITE_VERSION)==0 );
drh6aa5f152009-08-19 15:57:07 +0000137** </pre></blockquote>
drh6ed48bf2007-06-14 20:57:18 +0000138**
drh33c1be32008-01-30 16:16:14 +0000139** The sqlite3_libversion() function returns the same information as is
140** in the sqlite3_version[] string constant. The function is provided
141** for use in DLLs since DLL users usually do not have direct access to string
drh47baebc2009-08-14 16:01:24 +0000142** constants within the DLL. Similarly, the sqlite3_sourceid() function
143** returns the same information as is in the [SQLITE_SOURCE_ID] #define of
144** the header file.
drh33c1be32008-01-30 16:16:14 +0000145**
drh4e0b31c2009-09-02 19:04:24 +0000146** See also: [sqlite_version()] and [sqlite_source_id()].
147**
drh8b39db12009-02-18 18:37:58 +0000148** Requirements: [H10021] [H10022] [H10023]
drhb217a572000-08-22 13:40:18 +0000149*/
drh73be5012007-08-08 12:11:21 +0000150SQLITE_EXTERN const char sqlite3_version[];
drha3f70cb2004-09-30 14:24:50 +0000151const char *sqlite3_libversion(void);
drh47baebc2009-08-14 16:01:24 +0000152const char *sqlite3_sourceid(void);
danielk197799ba19e2005-02-05 07:33:34 +0000153int sqlite3_libversion_number(void);
154
155/*
drh9a247912008-07-22 18:45:08 +0000156** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
drhb67e8bf2007-08-30 20:09:48 +0000157**
drh33c1be32008-01-30 16:16:14 +0000158** SQLite can be compiled with or without mutexes. When
drh6aa5f152009-08-19 15:57:07 +0000159** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
drhafacce02008-09-02 21:35:03 +0000160** are enabled and SQLite is threadsafe. When the
161** [SQLITE_THREADSAFE] macro is 0,
drh33c1be32008-01-30 16:16:14 +0000162** the mutexes are omitted. Without the mutexes, it is not safe
mihailim362cc832008-06-21 06:16:42 +0000163** to use SQLite concurrently from more than one thread.
drhb67e8bf2007-08-30 20:09:48 +0000164**
mihailim362cc832008-06-21 06:16:42 +0000165** Enabling mutexes incurs a measurable performance penalty.
drh33c1be32008-01-30 16:16:14 +0000166** So if speed is of utmost importance, it makes sense to disable
167** the mutexes. But for maximum safety, mutexes should be enabled.
168** The default behavior is for mutexes to be enabled.
169**
drh6aa5f152009-08-19 15:57:07 +0000170** This interface can be used by an application to make sure that the
drh33c1be32008-01-30 16:16:14 +0000171** version of SQLite that it is linking against was compiled with
drh4766b292008-06-26 02:53:02 +0000172** the desired setting of the [SQLITE_THREADSAFE] macro.
173**
174** This interface only reports on the compile-time mutex setting
175** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
176** SQLITE_THREADSAFE=1 then mutexes are enabled by default but
177** can be fully or partially disabled using a call to [sqlite3_config()]
178** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
179** or [SQLITE_CONFIG_MUTEX]. The return value of this function shows
180** only the default compile-time setting, not any run-time changes
181** to that setting.
drh33c1be32008-01-30 16:16:14 +0000182**
drhafacce02008-09-02 21:35:03 +0000183** See the [threading mode] documentation for additional information.
184**
drh8b39db12009-02-18 18:37:58 +0000185** Requirements: [H10101] [H10102]
drhb67e8bf2007-08-30 20:09:48 +0000186*/
187int sqlite3_threadsafe(void);
188
189/*
drh9cd29642008-07-23 00:52:55 +0000190** CAPI3REF: Database Connection Handle {H12000} <S40200>
drha06f17f2008-05-11 11:07:06 +0000191** KEYWORDS: {database connection} {database connections}
drh6ed48bf2007-06-14 20:57:18 +0000192**
mihailim362cc832008-06-21 06:16:42 +0000193** Each open SQLite database is represented by a pointer to an instance of
194** the opaque structure named "sqlite3". It is useful to think of an sqlite3
drh8bacf972007-08-25 16:21:29 +0000195** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
mihailim362cc832008-06-21 06:16:42 +0000196** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
197** is its destructor. There are many other interfaces (such as
198** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
199** [sqlite3_busy_timeout()] to name but three) that are methods on an
200** sqlite3 object.
drh75897232000-05-29 14:26:00 +0000201*/
drh9bb575f2004-09-06 17:24:11 +0000202typedef struct sqlite3 sqlite3;
danielk197765904932004-05-26 06:18:37 +0000203
drh75897232000-05-29 14:26:00 +0000204/*
drh9cd29642008-07-23 00:52:55 +0000205** CAPI3REF: 64-Bit Integer Types {H10200} <S10110>
drh33c1be32008-01-30 16:16:14 +0000206** KEYWORDS: sqlite_int64 sqlite_uint64
drh6ed48bf2007-06-14 20:57:18 +0000207**
drh33c1be32008-01-30 16:16:14 +0000208** Because there is no cross-platform way to specify 64-bit integer types
drhfddfa2d2007-12-05 18:05:16 +0000209** SQLite includes typedefs for 64-bit signed and unsigned integers.
drh6ed48bf2007-06-14 20:57:18 +0000210**
mihailim362cc832008-06-21 06:16:42 +0000211** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
212** The sqlite_int64 and sqlite_uint64 types are supported for backwards
213** compatibility only.
drh33c1be32008-01-30 16:16:14 +0000214**
drh8b39db12009-02-18 18:37:58 +0000215** Requirements: [H10201] [H10202]
drhefad9992004-06-22 12:13:55 +0000216*/
drh27436af2006-03-28 23:57:17 +0000217#ifdef SQLITE_INT64_TYPE
drh9b8f4472006-04-04 01:54:55 +0000218 typedef SQLITE_INT64_TYPE sqlite_int64;
drh27436af2006-03-28 23:57:17 +0000219 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
220#elif defined(_MSC_VER) || defined(__BORLANDC__)
drhefad9992004-06-22 12:13:55 +0000221 typedef __int64 sqlite_int64;
drh1211de32004-07-26 12:24:22 +0000222 typedef unsigned __int64 sqlite_uint64;
drhefad9992004-06-22 12:13:55 +0000223#else
224 typedef long long int sqlite_int64;
drh1211de32004-07-26 12:24:22 +0000225 typedef unsigned long long int sqlite_uint64;
drhefad9992004-06-22 12:13:55 +0000226#endif
drh6d2069d2007-08-14 01:58:53 +0000227typedef sqlite_int64 sqlite3_int64;
228typedef sqlite_uint64 sqlite3_uint64;
drhefad9992004-06-22 12:13:55 +0000229
drhb37df7b2005-10-13 02:09:49 +0000230/*
231** If compiling for a processor that lacks floating point support,
mihailim362cc832008-06-21 06:16:42 +0000232** substitute integer for floating-point.
drhb37df7b2005-10-13 02:09:49 +0000233*/
234#ifdef SQLITE_OMIT_FLOATING_POINT
drh6d2069d2007-08-14 01:58:53 +0000235# define double sqlite3_int64
drhb37df7b2005-10-13 02:09:49 +0000236#endif
drhefad9992004-06-22 12:13:55 +0000237
238/*
drh9cd29642008-07-23 00:52:55 +0000239** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200>
drh75897232000-05-29 14:26:00 +0000240**
mihailim362cc832008-06-21 06:16:42 +0000241** This routine is the destructor for the [sqlite3] object.
drh33c1be32008-01-30 16:16:14 +0000242**
drh7db29fb2009-10-20 14:23:09 +0000243** Applications must [sqlite3_finalize | finalize] all [prepared statements]
mihailim15194222008-06-22 09:55:14 +0000244** and [sqlite3_blob_close | close] all [BLOB handles] associated with
mihailim362cc832008-06-21 06:16:42 +0000245** the [sqlite3] object prior to attempting to close the object.
drh55b0cf02008-06-19 17:54:33 +0000246**
mihailim362cc832008-06-21 06:16:42 +0000247** If [sqlite3_close()] is invoked while a transaction is open,
drh55b0cf02008-06-19 17:54:33 +0000248** the transaction is automatically rolled back.
drh33c1be32008-01-30 16:16:14 +0000249**
drh8b39db12009-02-18 18:37:58 +0000250** The C parameter to [sqlite3_close(C)] must be either a NULL
251** pointer or an [sqlite3] object pointer obtained
252** from [sqlite3_open()], [sqlite3_open16()], or
253** [sqlite3_open_v2()], and not previously closed.
drh33c1be32008-01-30 16:16:14 +0000254**
drh8b39db12009-02-18 18:37:58 +0000255** Requirements:
256** [H12011] [H12012] [H12013] [H12014] [H12015] [H12019]
drh75897232000-05-29 14:26:00 +0000257*/
danielk1977f9d64d22004-06-19 08:18:07 +0000258int sqlite3_close(sqlite3 *);
drh75897232000-05-29 14:26:00 +0000259
260/*
261** The type for a callback function.
drh6ed48bf2007-06-14 20:57:18 +0000262** This is legacy and deprecated. It is included for historical
263** compatibility and is not documented.
drh75897232000-05-29 14:26:00 +0000264*/
drh12057d52004-09-06 17:34:12 +0000265typedef int (*sqlite3_callback)(void*,int,char**, char**);
drh75897232000-05-29 14:26:00 +0000266
267/*
drh9cd29642008-07-23 00:52:55 +0000268** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000>
drh6ed48bf2007-06-14 20:57:18 +0000269**
mihailim362cc832008-06-21 06:16:42 +0000270** The sqlite3_exec() interface is a convenient way of running one or more
271** SQL statements without having to write a lot of C code. The UTF-8 encoded
272** SQL statements are passed in as the second parameter to sqlite3_exec().
273** The statements are evaluated one by one until either an error or
274** an interrupt is encountered, or until they are all done. The 3rd parameter
275** is an optional callback that is invoked once for each row of any query
276** results produced by the SQL statements. The 5th parameter tells where
drh33c1be32008-01-30 16:16:14 +0000277** to write any error messages.
drh75897232000-05-29 14:26:00 +0000278**
drh35c61902008-05-20 15:44:30 +0000279** The error message passed back through the 5th parameter is held
280** in memory obtained from [sqlite3_malloc()]. To avoid a memory leak,
281** the calling application should call [sqlite3_free()] on any error
282** message returned through the 5th parameter when it has finished using
283** the error message.
284**
285** If the SQL statement in the 2nd parameter is NULL or an empty string
mihailim362cc832008-06-21 06:16:42 +0000286** or a string containing only whitespace and comments, then no SQL
287** statements are evaluated and the database is not changed.
drh35c61902008-05-20 15:44:30 +0000288**
drh33c1be32008-01-30 16:16:14 +0000289** The sqlite3_exec() interface is implemented in terms of
290** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
drh35c61902008-05-20 15:44:30 +0000291** The sqlite3_exec() routine does nothing to the database that cannot be done
drh33c1be32008-01-30 16:16:14 +0000292** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
drh75897232000-05-29 14:26:00 +0000293**
drh8b39db12009-02-18 18:37:58 +0000294** The first parameter to [sqlite3_exec()] must be an valid and open
295** [database connection].
mihailima3f64902008-06-21 13:35:56 +0000296**
drh8b39db12009-02-18 18:37:58 +0000297** The database connection must not be closed while
298** [sqlite3_exec()] is running.
drh75897232000-05-29 14:26:00 +0000299**
drh8b39db12009-02-18 18:37:58 +0000300** The calling function should use [sqlite3_free()] to free
301** the memory that *errmsg is left pointing at once the error
302** message is no longer needed.
drh75897232000-05-29 14:26:00 +0000303**
drh8b39db12009-02-18 18:37:58 +0000304** The SQL statement text in the 2nd parameter to [sqlite3_exec()]
305** must remain unchanged while [sqlite3_exec()] is running.
drhf50bebf2008-05-19 23:51:55 +0000306**
drh8b39db12009-02-18 18:37:58 +0000307** Requirements:
308** [H12101] [H12102] [H12104] [H12105] [H12107] [H12110] [H12113] [H12116]
309** [H12119] [H12122] [H12125] [H12131] [H12134] [H12137] [H12138]
drh75897232000-05-29 14:26:00 +0000310*/
danielk19776f8a5032004-05-10 10:34:51 +0000311int sqlite3_exec(
drh6ed48bf2007-06-14 20:57:18 +0000312 sqlite3*, /* An open database */
shane236ce972008-05-30 15:35:30 +0000313 const char *sql, /* SQL to be evaluated */
drh6ed48bf2007-06-14 20:57:18 +0000314 int (*callback)(void*,int,char**,char**), /* Callback function */
315 void *, /* 1st argument to callback */
316 char **errmsg /* Error msg written here */
drh75897232000-05-29 14:26:00 +0000317);
318
drh58b95762000-06-02 01:17:37 +0000319/*
drhb25f9d82008-07-23 15:40:06 +0000320** CAPI3REF: Result Codes {H10210} <S10700>
drh33c1be32008-01-30 16:16:14 +0000321** KEYWORDS: SQLITE_OK {error code} {error codes}
mihailimefc8e8a2008-06-21 16:47:09 +0000322** KEYWORDS: {result code} {result codes}
drh6ed48bf2007-06-14 20:57:18 +0000323**
324** Many SQLite functions return an integer result code from the set shown
drh33c1be32008-01-30 16:16:14 +0000325** here in order to indicates success or failure.
drh6ed48bf2007-06-14 20:57:18 +0000326**
drh4766b292008-06-26 02:53:02 +0000327** New error codes may be added in future versions of SQLite.
328**
drh6ed48bf2007-06-14 20:57:18 +0000329** See also: [SQLITE_IOERR_READ | extended result codes]
drh58b95762000-06-02 01:17:37 +0000330*/
drh717e6402001-09-27 03:22:32 +0000331#define SQLITE_OK 0 /* Successful result */
drh15b9a152006-01-31 20:49:13 +0000332/* beginning-of-error-codes */
drh717e6402001-09-27 03:22:32 +0000333#define SQLITE_ERROR 1 /* SQL error or missing database */
drh89e0dde2007-12-12 12:25:21 +0000334#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
drh717e6402001-09-27 03:22:32 +0000335#define SQLITE_PERM 3 /* Access permission denied */
336#define SQLITE_ABORT 4 /* Callback routine requested an abort */
337#define SQLITE_BUSY 5 /* The database file is locked */
338#define SQLITE_LOCKED 6 /* A table in the database is locked */
339#define SQLITE_NOMEM 7 /* A malloc() failed */
340#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
drh24cd67e2004-05-10 16:18:47 +0000341#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
drh717e6402001-09-27 03:22:32 +0000342#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
343#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
drh2db0bbc2005-08-11 02:10:18 +0000344#define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
drh717e6402001-09-27 03:22:32 +0000345#define SQLITE_FULL 13 /* Insertion failed because database is full */
346#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
drh4f0ee682007-03-30 20:43:40 +0000347#define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */
drh24cd67e2004-05-10 16:18:47 +0000348#define SQLITE_EMPTY 16 /* Database is empty */
drh717e6402001-09-27 03:22:32 +0000349#define SQLITE_SCHEMA 17 /* The database schema changed */
drhc797d4d2007-05-08 01:08:49 +0000350#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
danielk19776eb91d22007-09-21 04:27:02 +0000351#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
drh8aff1012001-12-22 14:49:24 +0000352#define SQLITE_MISMATCH 20 /* Data type mismatch */
drh247be432002-05-10 05:44:55 +0000353#define SQLITE_MISUSE 21 /* Library used incorrectly */
drh8766c342002-11-09 00:33:15 +0000354#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
drhed6c8672003-01-12 18:02:16 +0000355#define SQLITE_AUTH 23 /* Authorization denied */
drh1c2d8412003-03-31 00:30:47 +0000356#define SQLITE_FORMAT 24 /* Auxiliary database format error */
danielk19776f8a5032004-05-10 10:34:51 +0000357#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
drhc602f9a2004-02-12 19:01:04 +0000358#define SQLITE_NOTADB 26 /* File opened that is not a database file */
danielk19776f8a5032004-05-10 10:34:51 +0000359#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
360#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
drh15b9a152006-01-31 20:49:13 +0000361/* end-of-error-codes */
drh717e6402001-09-27 03:22:32 +0000362
drhaf9ff332002-01-16 21:00:27 +0000363/*
drhb25f9d82008-07-23 15:40:06 +0000364** CAPI3REF: Extended Result Codes {H10220} <S10700>
drh33c1be32008-01-30 16:16:14 +0000365** KEYWORDS: {extended error code} {extended error codes}
mihailimefc8e8a2008-06-21 16:47:09 +0000366** KEYWORDS: {extended result code} {extended result codes}
drh4ac285a2006-09-15 07:28:50 +0000367**
drh6ed48bf2007-06-14 20:57:18 +0000368** In its default configuration, SQLite API routines return one of 26 integer
mihailim362cc832008-06-21 06:16:42 +0000369** [SQLITE_OK | result codes]. However, experience has shown that many of
370** these result codes are too coarse-grained. They do not provide as
drhf5befa02007-12-06 02:42:07 +0000371** much information about problems as programmers might like. In an effort to
drh6ed48bf2007-06-14 20:57:18 +0000372** address this, newer versions of SQLite (version 3.3.8 and later) include
373** support for additional result codes that provide more detailed information
drh33c1be32008-01-30 16:16:14 +0000374** about errors. The extended result codes are enabled or disabled
mihailim362cc832008-06-21 06:16:42 +0000375** on a per database connection basis using the
376** [sqlite3_extended_result_codes()] API.
mihailima3f64902008-06-21 13:35:56 +0000377**
drh33c1be32008-01-30 16:16:14 +0000378** Some of the available extended result codes are listed here.
379** One may expect the number of extended result codes will be expand
380** over time. Software that uses extended result codes should expect
381** to see new result codes in future releases of SQLite.
drh4ac285a2006-09-15 07:28:50 +0000382**
383** The SQLITE_OK result code will never be extended. It will always
384** be exactly zero.
drh4ac285a2006-09-15 07:28:50 +0000385*/
danielk1977861f7452008-06-05 11:39:11 +0000386#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
387#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
388#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
389#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
390#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
391#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
392#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
393#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
394#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
395#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
396#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
397#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
398#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
399#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
aswift5b1a2562008-08-22 00:22:35 +0000400#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
aswiftaebf4132008-11-21 00:10:35 +0000401#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
402#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
danielk1977404ca072009-03-16 13:19:36 +0000403#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8) )
404
drh4ac285a2006-09-15 07:28:50 +0000405/*
drh9cd29642008-07-23 00:52:55 +0000406** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
drh6d2069d2007-08-14 01:58:53 +0000407**
mlcreechb2799412008-03-07 03:20:31 +0000408** These bit values are intended for use in the
drh33c1be32008-01-30 16:16:14 +0000409** 3rd parameter to the [sqlite3_open_v2()] interface and
410** in the 4th parameter to the xOpen method of the
drhd84f9462007-08-15 11:28:56 +0000411** [sqlite3_vfs] object.
drh6d2069d2007-08-14 01:58:53 +0000412*/
shane089b0a42009-05-14 03:21:28 +0000413#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
414#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
415#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
416#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
417#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
418#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
419#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
420#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
421#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
422#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
423#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
424#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
425#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
426#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
drhf1f12682009-09-09 14:17:52 +0000427#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
428#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
drh6d2069d2007-08-14 01:58:53 +0000429
430/*
drh9cd29642008-07-23 00:52:55 +0000431** CAPI3REF: Device Characteristics {H10240} <H11120>
drh6d2069d2007-08-14 01:58:53 +0000432**
drh33c1be32008-01-30 16:16:14 +0000433** The xDeviceCapabilities method of the [sqlite3_io_methods]
drhfddfa2d2007-12-05 18:05:16 +0000434** object returns an integer which is a vector of the these
drh6d2069d2007-08-14 01:58:53 +0000435** bit values expressing I/O characteristics of the mass storage
436** device that holds the file that the [sqlite3_io_methods]
drh33c1be32008-01-30 16:16:14 +0000437** refers to.
drh6d2069d2007-08-14 01:58:53 +0000438**
drh33c1be32008-01-30 16:16:14 +0000439** The SQLITE_IOCAP_ATOMIC property means that all writes of
440** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
drh6d2069d2007-08-14 01:58:53 +0000441** mean that writes of blocks that are nnn bytes in size and
442** are aligned to an address which is an integer multiple of
drh33c1be32008-01-30 16:16:14 +0000443** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
drh6d2069d2007-08-14 01:58:53 +0000444** that when data is appended to a file, the data is appended
445** first then the size of the file is extended, never the other
drh33c1be32008-01-30 16:16:14 +0000446** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
drh6d2069d2007-08-14 01:58:53 +0000447** information is written to disk in the same order as calls
448** to xWrite().
449*/
450#define SQLITE_IOCAP_ATOMIC 0x00000001
451#define SQLITE_IOCAP_ATOMIC512 0x00000002
452#define SQLITE_IOCAP_ATOMIC1K 0x00000004
453#define SQLITE_IOCAP_ATOMIC2K 0x00000008
454#define SQLITE_IOCAP_ATOMIC4K 0x00000010
455#define SQLITE_IOCAP_ATOMIC8K 0x00000020
456#define SQLITE_IOCAP_ATOMIC16K 0x00000040
457#define SQLITE_IOCAP_ATOMIC32K 0x00000080
458#define SQLITE_IOCAP_ATOMIC64K 0x00000100
459#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
460#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
461
462/*
drhb25f9d82008-07-23 15:40:06 +0000463** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310>
drh6d2069d2007-08-14 01:58:53 +0000464**
drh33c1be32008-01-30 16:16:14 +0000465** SQLite uses one of these integer values as the second
drh6d2069d2007-08-14 01:58:53 +0000466** argument to calls it makes to the xLock() and xUnlock() methods
drh33c1be32008-01-30 16:16:14 +0000467** of an [sqlite3_io_methods] object.
drh6d2069d2007-08-14 01:58:53 +0000468*/
469#define SQLITE_LOCK_NONE 0
470#define SQLITE_LOCK_SHARED 1
471#define SQLITE_LOCK_RESERVED 2
472#define SQLITE_LOCK_PENDING 3
473#define SQLITE_LOCK_EXCLUSIVE 4
474
475/*
drh9cd29642008-07-23 00:52:55 +0000476** CAPI3REF: Synchronization Type Flags {H10260} <H11120>
drh6d2069d2007-08-14 01:58:53 +0000477**
drh33c1be32008-01-30 16:16:14 +0000478** When SQLite invokes the xSync() method of an
mlcreechb2799412008-03-07 03:20:31 +0000479** [sqlite3_io_methods] object it uses a combination of
drhfddfa2d2007-12-05 18:05:16 +0000480** these integer values as the second argument.
drh6d2069d2007-08-14 01:58:53 +0000481**
drh33c1be32008-01-30 16:16:14 +0000482** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
drh6d2069d2007-08-14 01:58:53 +0000483** sync operation only needs to flush data to mass storage. Inode
drheb0d6292009-04-04 14:04:58 +0000484** information need not be flushed. If the lower four bits of the flag
485** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
486** If the lower four bits equal SQLITE_SYNC_FULL, that means
shane7ba429a2008-11-10 17:08:49 +0000487** to use Mac OS X style fullsync instead of fsync().
drh6d2069d2007-08-14 01:58:53 +0000488*/
drh6d2069d2007-08-14 01:58:53 +0000489#define SQLITE_SYNC_NORMAL 0x00002
490#define SQLITE_SYNC_FULL 0x00003
491#define SQLITE_SYNC_DATAONLY 0x00010
492
drh6d2069d2007-08-14 01:58:53 +0000493/*
drh9cd29642008-07-23 00:52:55 +0000494** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
drh6d2069d2007-08-14 01:58:53 +0000495**
drh6aa5f152009-08-19 15:57:07 +0000496** An [sqlite3_file] object represents an open file in the
497** [sqlite3_vfs | OS interface layer]. Individual OS interface
498** implementations will
drh6d2069d2007-08-14 01:58:53 +0000499** want to subclass this object by appending additional fields
drh4ff7fa02007-09-01 18:17:21 +0000500** for their own use. The pMethods entry is a pointer to an
drhd84f9462007-08-15 11:28:56 +0000501** [sqlite3_io_methods] object that defines methods for performing
502** I/O operations on the open file.
drh6d2069d2007-08-14 01:58:53 +0000503*/
504typedef struct sqlite3_file sqlite3_file;
505struct sqlite3_file {
drh153c62c2007-08-24 03:51:33 +0000506 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
drh6d2069d2007-08-14 01:58:53 +0000507};
508
509/*
drh9cd29642008-07-23 00:52:55 +0000510** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110>
drh6d2069d2007-08-14 01:58:53 +0000511**
drh4766b292008-06-26 02:53:02 +0000512** Every file opened by the [sqlite3_vfs] xOpen method populates an
513** [sqlite3_file] object (or, more commonly, a subclass of the
514** [sqlite3_file] object) with a pointer to an instance of this object.
515** This object defines the methods used to perform various operations
516** against the open file represented by the [sqlite3_file] object.
drhd84f9462007-08-15 11:28:56 +0000517**
drh9afedcc2009-06-19 22:50:31 +0000518** If the xOpen method sets the sqlite3_file.pMethods element
519** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
520** may be invoked even if the xOpen reported that it failed. The
521** only way to prevent a call to xClose following a failed xOpen
522** is for the xOpen to set the sqlite3_file.pMethods element to NULL.
523**
drhfddfa2d2007-12-05 18:05:16 +0000524** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
525** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
shane7ba429a2008-11-10 17:08:49 +0000526** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
mihailim362cc832008-06-21 06:16:42 +0000527** flag may be ORed in to indicate that only the data of the file
528** and not its inode needs to be synced.
mihailima3f64902008-06-21 13:35:56 +0000529**
drhd84f9462007-08-15 11:28:56 +0000530** The integer values to xLock() and xUnlock() are one of
drh4ff7fa02007-09-01 18:17:21 +0000531** <ul>
532** <li> [SQLITE_LOCK_NONE],
drh79491ab2007-09-04 12:00:00 +0000533** <li> [SQLITE_LOCK_SHARED],
drh4ff7fa02007-09-01 18:17:21 +0000534** <li> [SQLITE_LOCK_RESERVED],
535** <li> [SQLITE_LOCK_PENDING], or
536** <li> [SQLITE_LOCK_EXCLUSIVE].
537** </ul>
mihailima3f64902008-06-21 13:35:56 +0000538** xLock() increases the lock. xUnlock() decreases the lock.
mihailim362cc832008-06-21 06:16:42 +0000539** The xCheckReservedLock() method checks whether any database connection,
540** either in this process or in some other process, is holding a RESERVED,
drhd84f9462007-08-15 11:28:56 +0000541** PENDING, or EXCLUSIVE lock on the file. It returns true
mihailim362cc832008-06-21 06:16:42 +0000542** if such a lock exists and false otherwise.
mihailima3f64902008-06-21 13:35:56 +0000543**
drhcc6bb3e2007-08-31 16:11:35 +0000544** The xFileControl() method is a generic interface that allows custom
545** VFS implementations to directly control an open file using the
mihailim362cc832008-06-21 06:16:42 +0000546** [sqlite3_file_control()] interface. The second "op" argument is an
mihailima3f64902008-06-21 13:35:56 +0000547** integer opcode. The third argument is a generic pointer intended to
mihailim362cc832008-06-21 06:16:42 +0000548** point to a structure that may contain arguments or space in which to
drhcc6bb3e2007-08-31 16:11:35 +0000549** write return values. Potential uses for xFileControl() might be
550** functions to enable blocking locks with timeouts, to change the
551** locking strategy (for example to use dot-file locks), to inquire
drh9e33c2c2007-08-31 18:34:59 +0000552** about the status of a lock, or to break stale locks. The SQLite
mihailima3f64902008-06-21 13:35:56 +0000553** core reserves all opcodes less than 100 for its own use.
drh4ff7fa02007-09-01 18:17:21 +0000554** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
mihailim362cc832008-06-21 06:16:42 +0000555** Applications that define a custom xFileControl method should use opcodes
drh9e33c2c2007-08-31 18:34:59 +0000556** greater than 100 to avoid conflicts.
drhd84f9462007-08-15 11:28:56 +0000557**
558** The xSectorSize() method returns the sector size of the
559** device that underlies the file. The sector size is the
560** minimum write that can be performed without disturbing
561** other bytes in the file. The xDeviceCharacteristics()
562** method returns a bit vector describing behaviors of the
563** underlying device:
564**
565** <ul>
drh4ff7fa02007-09-01 18:17:21 +0000566** <li> [SQLITE_IOCAP_ATOMIC]
567** <li> [SQLITE_IOCAP_ATOMIC512]
568** <li> [SQLITE_IOCAP_ATOMIC1K]
569** <li> [SQLITE_IOCAP_ATOMIC2K]
570** <li> [SQLITE_IOCAP_ATOMIC4K]
571** <li> [SQLITE_IOCAP_ATOMIC8K]
572** <li> [SQLITE_IOCAP_ATOMIC16K]
573** <li> [SQLITE_IOCAP_ATOMIC32K]
574** <li> [SQLITE_IOCAP_ATOMIC64K]
575** <li> [SQLITE_IOCAP_SAFE_APPEND]
576** <li> [SQLITE_IOCAP_SEQUENTIAL]
drhd84f9462007-08-15 11:28:56 +0000577** </ul>
578**
579** The SQLITE_IOCAP_ATOMIC property means that all writes of
580** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
581** mean that writes of blocks that are nnn bytes in size and
582** are aligned to an address which is an integer multiple of
583** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
584** that when data is appended to a file, the data is appended
585** first then the size of the file is extended, never the other
586** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
587** information is written to disk in the same order as calls
588** to xWrite().
drh4c17c3f2008-11-07 00:06:18 +0000589**
590** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
591** in the unread portions of the buffer with zeros. A VFS that
592** fails to zero-fill short reads might seem to work. However,
593** failure to zero-fill short reads will eventually lead to
594** database corruption.
drh6d2069d2007-08-14 01:58:53 +0000595*/
596typedef struct sqlite3_io_methods sqlite3_io_methods;
597struct sqlite3_io_methods {
598 int iVersion;
599 int (*xClose)(sqlite3_file*);
drh79491ab2007-09-04 12:00:00 +0000600 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
601 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
602 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
drh6d2069d2007-08-14 01:58:53 +0000603 int (*xSync)(sqlite3_file*, int flags);
drh79491ab2007-09-04 12:00:00 +0000604 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
drh6d2069d2007-08-14 01:58:53 +0000605 int (*xLock)(sqlite3_file*, int);
606 int (*xUnlock)(sqlite3_file*, int);
danielk1977861f7452008-06-05 11:39:11 +0000607 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
drhcc6bb3e2007-08-31 16:11:35 +0000608 int (*xFileControl)(sqlite3_file*, int op, void *pArg);
drh6d2069d2007-08-14 01:58:53 +0000609 int (*xSectorSize)(sqlite3_file*);
610 int (*xDeviceCharacteristics)(sqlite3_file*);
611 /* Additional methods may be added in future releases */
612};
613
614/*
drh9cd29642008-07-23 00:52:55 +0000615** CAPI3REF: Standard File Control Opcodes {H11310} <S30800>
drh9e33c2c2007-08-31 18:34:59 +0000616**
617** These integer constants are opcodes for the xFileControl method
mihailim362cc832008-06-21 06:16:42 +0000618** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
drh9e33c2c2007-08-31 18:34:59 +0000619** interface.
620**
drh33c1be32008-01-30 16:16:14 +0000621** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
mlcreechb2799412008-03-07 03:20:31 +0000622** opcode causes the xFileControl method to write the current state of
drh9e33c2c2007-08-31 18:34:59 +0000623** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
624** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
drh33c1be32008-01-30 16:16:14 +0000625** into an integer that the pArg argument points to. This capability
drh9e33c2c2007-08-31 18:34:59 +0000626** is used during testing and only needs to be supported when SQLITE_TEST
627** is defined.
628*/
629#define SQLITE_FCNTL_LOCKSTATE 1
aswiftaebf4132008-11-21 00:10:35 +0000630#define SQLITE_GET_LOCKPROXYFILE 2
631#define SQLITE_SET_LOCKPROXYFILE 3
632#define SQLITE_LAST_ERRNO 4
drh9e33c2c2007-08-31 18:34:59 +0000633
634/*
drh9cd29642008-07-23 00:52:55 +0000635** CAPI3REF: Mutex Handle {H17110} <S20130>
drh6d2069d2007-08-14 01:58:53 +0000636**
drhd84f9462007-08-15 11:28:56 +0000637** The mutex module within SQLite defines [sqlite3_mutex] to be an
drh33c1be32008-01-30 16:16:14 +0000638** abstract type for a mutex object. The SQLite core never looks
639** at the internal representation of an [sqlite3_mutex]. It only
drhd84f9462007-08-15 11:28:56 +0000640** deals with pointers to the [sqlite3_mutex] object.
drh6bdec4a2007-08-16 19:40:16 +0000641**
642** Mutexes are created using [sqlite3_mutex_alloc()].
drh6d2069d2007-08-14 01:58:53 +0000643*/
644typedef struct sqlite3_mutex sqlite3_mutex;
645
646/*
drh9cd29642008-07-23 00:52:55 +0000647** CAPI3REF: OS Interface Object {H11140} <S20100>
drh6d2069d2007-08-14 01:58:53 +0000648**
mihailim362cc832008-06-21 06:16:42 +0000649** An instance of the sqlite3_vfs object defines the interface between
650** the SQLite core and the underlying operating system. The "vfs"
drhd84f9462007-08-15 11:28:56 +0000651** in the name of the object stands for "virtual file system".
drh6d2069d2007-08-14 01:58:53 +0000652**
mihailim362cc832008-06-21 06:16:42 +0000653** The value of the iVersion field is initially 1 but may be larger in
654** future versions of SQLite. Additional fields may be appended to this
drh4766b292008-06-26 02:53:02 +0000655** object when the iVersion value is increased. Note that the structure
656** of the sqlite3_vfs object changes in the transaction between
657** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
658** modified.
drh6bdec4a2007-08-16 19:40:16 +0000659**
drh4ff7fa02007-09-01 18:17:21 +0000660** The szOsFile field is the size of the subclassed [sqlite3_file]
drhd84f9462007-08-15 11:28:56 +0000661** structure used by this VFS. mxPathname is the maximum length of
662** a pathname in this VFS.
663**
drhb4d58ae2008-02-21 20:17:06 +0000664** Registered sqlite3_vfs objects are kept on a linked list formed by
drh79491ab2007-09-04 12:00:00 +0000665** the pNext pointer. The [sqlite3_vfs_register()]
666** and [sqlite3_vfs_unregister()] interfaces manage this list
667** in a thread-safe way. The [sqlite3_vfs_find()] interface
drh4766b292008-06-26 02:53:02 +0000668** searches the list. Neither the application code nor the VFS
669** implementation should use the pNext pointer.
drhd84f9462007-08-15 11:28:56 +0000670**
mihailima3f64902008-06-21 13:35:56 +0000671** The pNext field is the only field in the sqlite3_vfs
drh1cc8c442007-08-24 16:08:29 +0000672** structure that SQLite will ever modify. SQLite will only access
673** or modify this field while holding a particular static mutex.
674** The application should never modify anything within the sqlite3_vfs
675** object once the object has been registered.
676**
drhd84f9462007-08-15 11:28:56 +0000677** The zName field holds the name of the VFS module. The name must
678** be unique across all VFS modules.
679**
drh032ca702008-12-10 11:44:30 +0000680** SQLite will guarantee that the zFilename parameter to xOpen
drh4766b292008-06-26 02:53:02 +0000681** is either a NULL pointer or string obtained
682** from xFullPathname(). SQLite further guarantees that
683** the string will be valid and unchanged until xClose() is
drh9afedcc2009-06-19 22:50:31 +0000684** called. Because of the previous sentence,
drh4766b292008-06-26 02:53:02 +0000685** the [sqlite3_file] can safely store a pointer to the
drh6d2069d2007-08-14 01:58:53 +0000686** filename if it needs to remember the filename for some reason.
drh4766b292008-06-26 02:53:02 +0000687** If the zFilename parameter is xOpen is a NULL pointer then xOpen
drh9afedcc2009-06-19 22:50:31 +0000688** must invent its own temporary name for the file. Whenever the
drh4766b292008-06-26 02:53:02 +0000689** xFilename parameter is NULL it will also be the case that the
690** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
drhd84f9462007-08-15 11:28:56 +0000691**
drh032ca702008-12-10 11:44:30 +0000692** The flags argument to xOpen() includes all bits set in
drhf5befa02007-12-06 02:42:07 +0000693** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
694** or [sqlite3_open16()] is used, then flags includes at least
drh032ca702008-12-10 11:44:30 +0000695** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
drh6d2069d2007-08-14 01:58:53 +0000696** If xOpen() opens a file read-only then it sets *pOutFlags to
mihailim362cc832008-06-21 06:16:42 +0000697** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
698**
drh032ca702008-12-10 11:44:30 +0000699** SQLite will also add one of the following flags to the xOpen()
drh6d2069d2007-08-14 01:58:53 +0000700** call, depending on the object being opened:
mihailim362cc832008-06-21 06:16:42 +0000701**
drh6d2069d2007-08-14 01:58:53 +0000702** <ul>
703** <li> [SQLITE_OPEN_MAIN_DB]
704** <li> [SQLITE_OPEN_MAIN_JOURNAL]
705** <li> [SQLITE_OPEN_TEMP_DB]
706** <li> [SQLITE_OPEN_TEMP_JOURNAL]
drh33f4e022007-09-03 15:19:34 +0000707** <li> [SQLITE_OPEN_TRANSIENT_DB]
drh6d2069d2007-08-14 01:58:53 +0000708** <li> [SQLITE_OPEN_SUBJOURNAL]
709** <li> [SQLITE_OPEN_MASTER_JOURNAL]
drh032ca702008-12-10 11:44:30 +0000710** </ul>
drhd84f9462007-08-15 11:28:56 +0000711**
drh6d2069d2007-08-14 01:58:53 +0000712** The file I/O implementation can use the object type flags to
mihailim362cc832008-06-21 06:16:42 +0000713** change the way it deals with files. For example, an application
mlcreechb2799412008-03-07 03:20:31 +0000714** that does not care about crash recovery or rollback might make
715** the open of a journal file a no-op. Writes to this journal would
mihailim362cc832008-06-21 06:16:42 +0000716** also be no-ops, and any attempt to read the journal would return
717** SQLITE_IOERR. Or the implementation might recognize that a database
718** file will be doing page-aligned sector reads and writes in a random
mlcreechb2799412008-03-07 03:20:31 +0000719** order and set up its I/O subsystem accordingly.
mihailim362cc832008-06-21 06:16:42 +0000720**
721** SQLite might also add one of the following flags to the xOpen method:
722**
drh6d2069d2007-08-14 01:58:53 +0000723** <ul>
724** <li> [SQLITE_OPEN_DELETEONCLOSE]
725** <li> [SQLITE_OPEN_EXCLUSIVE]
726** </ul>
mihailim362cc832008-06-21 06:16:42 +0000727**
drh032ca702008-12-10 11:44:30 +0000728** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
729** deleted when it is closed. The [SQLITE_OPEN_DELETEONCLOSE]
mihailim362cc832008-06-21 06:16:42 +0000730** will be set for TEMP databases, journals and for subjournals.
mihailim04bcc002008-06-22 10:21:27 +0000731**
shane089b0a42009-05-14 03:21:28 +0000732** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
733** with the [SQLITE_OPEN_CREATE] flag, which are both directly
734** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
735** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
736** SQLITE_OPEN_CREATE, is used to indicate that file should always
737** be created, and that it is an error if it already exists.
738** It is <i>not</i> used to indicate the file should be opened
739** for exclusive access.
mihailim362cc832008-06-21 06:16:42 +0000740**
drh032ca702008-12-10 11:44:30 +0000741** At least szOsFile bytes of memory are allocated by SQLite
mihailim362cc832008-06-21 06:16:42 +0000742** to hold the [sqlite3_file] structure passed as the third
drh032ca702008-12-10 11:44:30 +0000743** argument to xOpen. The xOpen method does not have to
drh9afedcc2009-06-19 22:50:31 +0000744** allocate the structure; it should just fill it in. Note that
745** the xOpen method must set the sqlite3_file.pMethods to either
746** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
747** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
748** element will be valid after xOpen returns regardless of the success
749** or failure of the xOpen call.
mihailim362cc832008-06-21 06:16:42 +0000750**
drh032ca702008-12-10 11:44:30 +0000751** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
mihailim362cc832008-06-21 06:16:42 +0000752** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
753** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
drh032ca702008-12-10 11:44:30 +0000754** to test whether a file is at least readable. The file can be a
drh6d2069d2007-08-14 01:58:53 +0000755** directory.
mihailim362cc832008-06-21 06:16:42 +0000756**
drh032ca702008-12-10 11:44:30 +0000757** SQLite will always allocate at least mxPathname+1 bytes for the
758** output buffer xFullPathname. The exact size of the output buffer
759** is also passed as a parameter to both methods. If the output buffer
mihailim362cc832008-06-21 06:16:42 +0000760** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
761** handled as a fatal error by SQLite, vfs implementations should endeavor
762** to prevent this by setting mxPathname to a sufficiently large value.
763**
drhd84f9462007-08-15 11:28:56 +0000764** The xRandomness(), xSleep(), and xCurrentTime() interfaces
765** are not strictly a part of the filesystem, but they are
766** included in the VFS structure for completeness.
drh6d2069d2007-08-14 01:58:53 +0000767** The xRandomness() function attempts to return nBytes bytes
768** of good-quality randomness into zOut. The return value is
mihailim362cc832008-06-21 06:16:42 +0000769** the actual number of bytes of randomness obtained.
770** The xSleep() method causes the calling thread to sleep for at
drhd84f9462007-08-15 11:28:56 +0000771** least the number of microseconds given. The xCurrentTime()
mihailim362cc832008-06-21 06:16:42 +0000772** method returns a Julian Day Number for the current date and time.
drh032ca702008-12-10 11:44:30 +0000773**
drh6d2069d2007-08-14 01:58:53 +0000774*/
drhd84f9462007-08-15 11:28:56 +0000775typedef struct sqlite3_vfs sqlite3_vfs;
776struct sqlite3_vfs {
drh6d2069d2007-08-14 01:58:53 +0000777 int iVersion; /* Structure version number */
778 int szOsFile; /* Size of subclassed sqlite3_file */
drh6d2069d2007-08-14 01:58:53 +0000779 int mxPathname; /* Maximum file pathname length */
drhd84f9462007-08-15 11:28:56 +0000780 sqlite3_vfs *pNext; /* Next registered VFS */
drhd84f9462007-08-15 11:28:56 +0000781 const char *zName; /* Name of this virtual file system */
drh1cc8c442007-08-24 16:08:29 +0000782 void *pAppData; /* Pointer to application-specific data */
drh153c62c2007-08-24 03:51:33 +0000783 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
drh6d2069d2007-08-14 01:58:53 +0000784 int flags, int *pOutFlags);
drh153c62c2007-08-24 03:51:33 +0000785 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
danielk1977861f7452008-06-05 11:39:11 +0000786 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
danielk1977adfb9b02007-09-17 07:02:56 +0000787 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
drh153c62c2007-08-24 03:51:33 +0000788 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
789 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
drh1875f7a2008-12-08 18:19:17 +0000790 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
drh153c62c2007-08-24 03:51:33 +0000791 void (*xDlClose)(sqlite3_vfs*, void*);
792 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
793 int (*xSleep)(sqlite3_vfs*, int microseconds);
794 int (*xCurrentTime)(sqlite3_vfs*, double*);
danielk1977bcb97fe2008-06-06 15:49:29 +0000795 int (*xGetLastError)(sqlite3_vfs*, int, char *);
drhd84f9462007-08-15 11:28:56 +0000796 /* New fields may be appended in figure versions. The iVersion
drh6d2069d2007-08-14 01:58:53 +0000797 ** value will increment whenever this happens. */
798};
799
drh50d3f902007-08-27 21:10:36 +0000800/*
drh9cd29642008-07-23 00:52:55 +0000801** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140>
drh50d3f902007-08-27 21:10:36 +0000802**
drh032ca702008-12-10 11:44:30 +0000803** These integer constants can be used as the third parameter to
drhfddfa2d2007-12-05 18:05:16 +0000804** the xAccess method of an [sqlite3_vfs] object. {END} They determine
mihailim04bcc002008-06-22 10:21:27 +0000805** what kind of permissions the xAccess method is looking for.
drh032ca702008-12-10 11:44:30 +0000806** With SQLITE_ACCESS_EXISTS, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000807** simply checks whether the file exists.
drh032ca702008-12-10 11:44:30 +0000808** With SQLITE_ACCESS_READWRITE, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000809** checks whether the file is both readable and writable.
drh032ca702008-12-10 11:44:30 +0000810** With SQLITE_ACCESS_READ, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000811** checks whether the file is readable.
drh50d3f902007-08-27 21:10:36 +0000812*/
danielk1977b4b47412007-08-17 15:53:36 +0000813#define SQLITE_ACCESS_EXISTS 0
814#define SQLITE_ACCESS_READWRITE 1
drh50d3f902007-08-27 21:10:36 +0000815#define SQLITE_ACCESS_READ 2
danielk1977b4b47412007-08-17 15:53:36 +0000816
drh6d2069d2007-08-14 01:58:53 +0000817/*
drh9cd29642008-07-23 00:52:55 +0000818** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100>
drh673299b2008-06-09 21:57:22 +0000819**
drhcb041342008-06-12 00:07:29 +0000820** The sqlite3_initialize() routine initializes the
drh4766b292008-06-26 02:53:02 +0000821** SQLite library. The sqlite3_shutdown() routine
drhcb041342008-06-12 00:07:29 +0000822** deallocates any resources that were allocated by sqlite3_initialize().
drh9524f4b2009-10-20 15:27:55 +0000823** This routines are designed to aid in process initialization and
824** shutdown on embedded systems. Workstation applications using
825** SQLite normally do not need to invoke either of these routines.
drh673299b2008-06-09 21:57:22 +0000826**
drhcb041342008-06-12 00:07:29 +0000827** A call to sqlite3_initialize() is an "effective" call if it is
828** the first time sqlite3_initialize() is invoked during the lifetime of
829** the process, or if it is the first time sqlite3_initialize() is invoked
830** following a call to sqlite3_shutdown(). Only an effective call
831** of sqlite3_initialize() does any initialization. All other calls
drh4766b292008-06-26 02:53:02 +0000832** are harmless no-ops.
drhcb041342008-06-12 00:07:29 +0000833**
drhd1a24402009-04-19 12:23:58 +0000834** A call to sqlite3_shutdown() is an "effective" call if it is the first
835** call to sqlite3_shutdown() since the last sqlite3_initialize(). Only
836** an effective call to sqlite3_shutdown() does any deinitialization.
drh9524f4b2009-10-20 15:27:55 +0000837** All other valid calls to sqlite3_shutdown() are harmless no-ops.
drhd1a24402009-04-19 12:23:58 +0000838**
drh9524f4b2009-10-20 15:27:55 +0000839** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
840** is not. The sqlite3_shutdown() interface must only be called from a
841** single thread. All open [database connections] must be closed and all
842** other SQLite resources must be deallocated prior to invoking
843** sqlite3_shutdown().
844**
845** Among other things, sqlite3_initialize() will invoke
drh55b0cf02008-06-19 17:54:33 +0000846** sqlite3_os_init(). Similarly, sqlite3_shutdown()
drh9524f4b2009-10-20 15:27:55 +0000847** will invoke sqlite3_os_end().
drh673299b2008-06-09 21:57:22 +0000848**
drhadfae6c2008-10-10 17:26:35 +0000849** The sqlite3_initialize() routine returns [SQLITE_OK] on success.
drhce5a5a02008-06-10 17:41:44 +0000850** If for some reason, sqlite3_initialize() is unable to initialize
851** the library (perhaps it is unable to allocate a needed resource such
drhadfae6c2008-10-10 17:26:35 +0000852** as a mutex) it returns an [error code] other than [SQLITE_OK].
drh673299b2008-06-09 21:57:22 +0000853**
drhce5a5a02008-06-10 17:41:44 +0000854** The sqlite3_initialize() routine is called internally by many other
drhcb041342008-06-12 00:07:29 +0000855** SQLite interfaces so that an application usually does not need to
drhce5a5a02008-06-10 17:41:44 +0000856** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
857** calls sqlite3_initialize() so the SQLite library will be automatically
858** initialized when [sqlite3_open()] is called if it has not be initialized
drhadfae6c2008-10-10 17:26:35 +0000859** already. However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
drhcb041342008-06-12 00:07:29 +0000860** compile-time option, then the automatic calls to sqlite3_initialize()
861** are omitted and the application must call sqlite3_initialize() directly
862** prior to using any other SQLite interface. For maximum portability,
863** it is recommended that applications always invoke sqlite3_initialize()
864** directly prior to using any other SQLite interface. Future releases
865** of SQLite may require this. In other words, the behavior exhibited
drhadfae6c2008-10-10 17:26:35 +0000866** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
drhcb041342008-06-12 00:07:29 +0000867** default behavior in some future release of SQLite.
drh673299b2008-06-09 21:57:22 +0000868**
drhcb041342008-06-12 00:07:29 +0000869** The sqlite3_os_init() routine does operating-system specific
870** initialization of the SQLite library. The sqlite3_os_end()
871** routine undoes the effect of sqlite3_os_init(). Typical tasks
872** performed by these routines include allocation or deallocation
873** of static resources, initialization of global variables,
874** setting up a default [sqlite3_vfs] module, or setting up
mihailima3f64902008-06-21 13:35:56 +0000875** a default configuration using [sqlite3_config()].
drh673299b2008-06-09 21:57:22 +0000876**
drhcb041342008-06-12 00:07:29 +0000877** The application should never invoke either sqlite3_os_init()
878** or sqlite3_os_end() directly. The application should only invoke
879** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
mihailima3f64902008-06-21 13:35:56 +0000880** interface is called automatically by sqlite3_initialize() and
drhcb041342008-06-12 00:07:29 +0000881** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
882** implementations for sqlite3_os_init() and sqlite3_os_end()
shane7c7c3112009-08-17 15:31:23 +0000883** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
drh6aa5f152009-08-19 15:57:07 +0000884** When [custom builds | built for other platforms]
885** (using the [SQLITE_OS_OTHER=1] compile-time
drhcb041342008-06-12 00:07:29 +0000886** option) the application must supply a suitable implementation for
887** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
888** implementation of sqlite3_os_init() or sqlite3_os_end()
drhadfae6c2008-10-10 17:26:35 +0000889** must return [SQLITE_OK] on success and some other [error code] upon
drhcb041342008-06-12 00:07:29 +0000890** failure.
drh673299b2008-06-09 21:57:22 +0000891*/
drhce5a5a02008-06-10 17:41:44 +0000892int sqlite3_initialize(void);
drh673299b2008-06-09 21:57:22 +0000893int sqlite3_shutdown(void);
drhcb041342008-06-12 00:07:29 +0000894int sqlite3_os_init(void);
895int sqlite3_os_end(void);
drh673299b2008-06-09 21:57:22 +0000896
drhce5a5a02008-06-10 17:41:44 +0000897/*
drhadfae6c2008-10-10 17:26:35 +0000898** CAPI3REF: Configuring The SQLite Library {H14100} <S20000><S30200>
drhd5a68d32008-08-04 13:44:57 +0000899** EXPERIMENTAL
drhce5a5a02008-06-10 17:41:44 +0000900**
901** The sqlite3_config() interface is used to make global configuration
902** changes to SQLite in order to tune SQLite to the specific needs of
903** the application. The default configuration is recommended for most
904** applications and so this routine is usually not necessary. It is
905** provided to support rare applications with unusual needs.
906**
907** The sqlite3_config() interface is not threadsafe. The application
908** must insure that no other SQLite interfaces are invoked by other
909** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
910** may only be invoked prior to library initialization using
911** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
912** Note, however, that sqlite3_config() can be called as part of the
drh40257ff2008-06-13 18:24:27 +0000913** implementation of an application-defined [sqlite3_os_init()].
drhce5a5a02008-06-10 17:41:44 +0000914**
915** The first argument to sqlite3_config() is an integer
916** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
917** what property of SQLite is to be configured. Subsequent arguments
918** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
919** in the first argument.
920**
drhadfae6c2008-10-10 17:26:35 +0000921** When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
mihailima3f64902008-06-21 13:35:56 +0000922** If the option is unknown or SQLite is unable to set the option
drh40257ff2008-06-13 18:24:27 +0000923** then this routine returns a non-zero [error code].
drhadfae6c2008-10-10 17:26:35 +0000924**
drh8b39db12009-02-18 18:37:58 +0000925** Requirements:
926** [H14103] [H14106] [H14120] [H14123] [H14126] [H14129] [H14132] [H14135]
927** [H14138] [H14141] [H14144] [H14147] [H14150] [H14153] [H14156] [H14159]
928** [H14162] [H14165] [H14168]
drhce5a5a02008-06-10 17:41:44 +0000929*/
shanea79c3cc2008-08-11 17:27:01 +0000930SQLITE_EXPERIMENTAL int sqlite3_config(int, ...);
drhce5a5a02008-06-10 17:41:44 +0000931
932/*
drhf8cecda2008-10-10 23:48:25 +0000933** CAPI3REF: Configure database connections {H14200} <S20000>
drhd5a68d32008-08-04 13:44:57 +0000934** EXPERIMENTAL
drh633e6d52008-07-28 19:34:53 +0000935**
936** The sqlite3_db_config() interface is used to make configuration
drh2462e322008-07-31 14:47:54 +0000937** changes to a [database connection]. The interface is similar to
938** [sqlite3_config()] except that the changes apply to a single
939** [database connection] (specified in the first argument). The
940** sqlite3_db_config() interface can only be used immediately after
941** the database connection is created using [sqlite3_open()],
942** [sqlite3_open16()], or [sqlite3_open_v2()].
943**
944** The second argument to sqlite3_db_config(D,V,...) is the
945** configuration verb - an integer code that indicates what
946** aspect of the [database connection] is being configured.
drhe9d1c722008-08-04 20:13:26 +0000947** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
drh2462e322008-07-31 14:47:54 +0000948** New verbs are likely to be added in future releases of SQLite.
drhe9d1c722008-08-04 20:13:26 +0000949** Additional arguments depend on the verb.
drhf8cecda2008-10-10 23:48:25 +0000950**
drh8b39db12009-02-18 18:37:58 +0000951** Requirements:
952** [H14203] [H14206] [H14209] [H14212] [H14215]
drh633e6d52008-07-28 19:34:53 +0000953*/
shanea79c3cc2008-08-11 17:27:01 +0000954SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...);
drh633e6d52008-07-28 19:34:53 +0000955
956/*
drh9cd29642008-07-23 00:52:55 +0000957** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
drhd5a68d32008-08-04 13:44:57 +0000958** EXPERIMENTAL
drhfec00ea2008-06-14 16:56:21 +0000959**
960** An instance of this object defines the interface between SQLite
mihailima3f64902008-06-21 13:35:56 +0000961** and low-level memory allocation routines.
drhfec00ea2008-06-14 16:56:21 +0000962**
963** This object is used in only one place in the SQLite interface.
964** A pointer to an instance of this object is the argument to
drh4766b292008-06-26 02:53:02 +0000965** [sqlite3_config()] when the configuration option is
drh6aa5f152009-08-19 15:57:07 +0000966** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
967** By creating an instance of this object
968** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
969** during configuration, an application can specify an alternative
970** memory allocation subsystem for SQLite to use for all of its
971** dynamic memory needs.
drhfec00ea2008-06-14 16:56:21 +0000972**
drh6aa5f152009-08-19 15:57:07 +0000973** Note that SQLite comes with several [built-in memory allocators]
974** that are perfectly adequate for the overwhelming majority of applications
drhfec00ea2008-06-14 16:56:21 +0000975** and that this object is only useful to a tiny minority of applications
976** with specialized memory allocation requirements. This object is
977** also used during testing of SQLite in order to specify an alternative
978** memory allocator that simulates memory out-of-memory conditions in
979** order to verify that SQLite recovers gracefully from such
980** conditions.
981**
drh6aa5f152009-08-19 15:57:07 +0000982** The xMalloc and xFree methods must work like the
983** malloc() and free() functions from the standard C library.
984** The xRealloc method must work like realloc() from the standard C library
985** with the exception that if the second argument to xRealloc is zero,
986** xRealloc must be a no-op - it must not perform any allocation or
987** deallocation. SQLite guaranteeds that the second argument to
988** xRealloc is always a value returned by a prior call to xRoundup.
989** And so in cases where xRoundup always returns a positive number,
990** xRealloc can perform exactly as the standard library realloc() and
991** still be in compliance with this specification.
drhfec00ea2008-06-14 16:56:21 +0000992**
993** xSize should return the allocated size of a memory allocation
994** previously obtained from xMalloc or xRealloc. The allocated size
995** is always at least as big as the requested size but may be larger.
996**
997** The xRoundup method returns what would be the allocated size of
998** a memory allocation given a particular requested size. Most memory
999** allocators round up memory allocations at least to the next multiple
mihailima3f64902008-06-21 13:35:56 +00001000** of 8. Some allocators round up to a larger multiple or to a power of 2.
drh6aa5f152009-08-19 15:57:07 +00001001** Every memory allocation request coming in through [sqlite3_malloc()]
1002** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1003** that causes the corresponding memory allocation to fail.
drhe5ae5732008-06-15 02:51:47 +00001004**
drhfec00ea2008-06-14 16:56:21 +00001005** The xInit method initializes the memory allocator. (For example,
1006** it might allocate any require mutexes or initialize internal data
1007** structures. The xShutdown method is invoked (indirectly) by
1008** [sqlite3_shutdown()] and should deallocate any resources acquired
1009** by xInit. The pAppData pointer is used as the only parameter to
1010** xInit and xShutdown.
drh9ac06502009-08-17 13:42:29 +00001011**
1012** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1013** the xInit method, so the xInit method need not be threadsafe. The
1014** xShutdown method is only called from [sqlite3_shutdown()] so it does
drh6aa5f152009-08-19 15:57:07 +00001015** not need to be threadsafe either. For all other methods, SQLite
1016** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1017** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1018** it is by default) and so the methods are automatically serialized.
1019** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1020** methods must be threadsafe or else make their own arrangements for
1021** serialization.
drh9ac06502009-08-17 13:42:29 +00001022**
1023** SQLite will never invoke xInit() more than once without an intervening
1024** call to xShutdown().
drhfec00ea2008-06-14 16:56:21 +00001025*/
1026typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1027struct sqlite3_mem_methods {
1028 void *(*xMalloc)(int); /* Memory allocation function */
1029 void (*xFree)(void*); /* Free a prior allocation */
1030 void *(*xRealloc)(void*,int); /* Resize an allocation */
1031 int (*xSize)(void*); /* Return the size of an allocation */
1032 int (*xRoundup)(int); /* Round up request size to allocation size */
1033 int (*xInit)(void*); /* Initialize the memory allocator */
1034 void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1035 void *pAppData; /* Argument to xInit() and xShutdown() */
1036};
1037
1038/*
drh9cd29642008-07-23 00:52:55 +00001039** CAPI3REF: Configuration Options {H10160} <S20000>
drhd5a68d32008-08-04 13:44:57 +00001040** EXPERIMENTAL
drhce5a5a02008-06-10 17:41:44 +00001041**
1042** These constants are the available integer configuration options that
1043** can be passed as the first argument to the [sqlite3_config()] interface.
mihailima3f64902008-06-21 13:35:56 +00001044**
drha911abe2008-07-16 13:29:51 +00001045** New configuration options may be added in future releases of SQLite.
1046** Existing configuration options might be discontinued. Applications
1047** should check the return code from [sqlite3_config()] to make sure that
1048** the call worked. The [sqlite3_config()] interface will return a
1049** non-zero [error code] if a discontinued or unsupported configuration option
1050** is invoked.
1051**
drhce5a5a02008-06-10 17:41:44 +00001052** <dl>
1053** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1054** <dd>There are no arguments to this option. This option disables
1055** all mutexing and puts SQLite into a mode where it can only be used
1056** by a single thread.</dd>
1057**
1058** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1059** <dd>There are no arguments to this option. This option disables
1060** mutexing on [database connection] and [prepared statement] objects.
1061** The application is responsible for serializing access to
1062** [database connections] and [prepared statements]. But other mutexes
1063** are enabled so that SQLite will be safe to use in a multi-threaded
drhafacce02008-09-02 21:35:03 +00001064** environment as long as no two threads attempt to use the same
1065** [database connection] at the same time. See the [threading mode]
1066** documentation for additional information.</dd>
drhce5a5a02008-06-10 17:41:44 +00001067**
1068** <dt>SQLITE_CONFIG_SERIALIZED</dt>
1069** <dd>There are no arguments to this option. This option enables
1070** all mutexes including the recursive
1071** mutexes on [database connection] and [prepared statement] objects.
1072** In this mode (which is the default when SQLite is compiled with
drh4766b292008-06-26 02:53:02 +00001073** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
drhce5a5a02008-06-10 17:41:44 +00001074** to [database connections] and [prepared statements] so that the
1075** application is free to use the same [database connection] or the
drh31d38cf2008-07-12 20:35:08 +00001076** same [prepared statement] in different threads at the same time.
drhafacce02008-09-02 21:35:03 +00001077** See the [threading mode] documentation for additional information.</dd>
drhce5a5a02008-06-10 17:41:44 +00001078**
1079** <dt>SQLITE_CONFIG_MALLOC</dt>
drhfec00ea2008-06-14 16:56:21 +00001080** <dd>This option takes a single argument which is a pointer to an
mihailimdb4f2ad2008-06-21 11:20:48 +00001081** instance of the [sqlite3_mem_methods] structure. The argument specifies
1082** alternative low-level memory allocation routines to be used in place of
drhfec00ea2008-06-14 16:56:21 +00001083** the memory allocation routines built into SQLite.</dd>
drhce5a5a02008-06-10 17:41:44 +00001084**
drh33589792008-06-18 13:27:46 +00001085** <dt>SQLITE_CONFIG_GETMALLOC</dt>
1086** <dd>This option takes a single argument which is a pointer to an
1087** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
1088** structure is filled with the currently defined memory allocation routines.
1089** This option can be used to overload the default memory allocation
1090** routines with a wrapper that simulations memory allocation failure or
1091** tracks memory usage, for example.</dd>
1092**
drhfec00ea2008-06-14 16:56:21 +00001093** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
danielk197795c232d2008-07-28 05:22:35 +00001094** <dd>This option takes single argument of type int, interpreted as a
1095** boolean, which enables or disables the collection of memory allocation
1096** statistics. When disabled, the following SQLite interfaces become
1097** non-operational:
drhce5a5a02008-06-10 17:41:44 +00001098** <ul>
1099** <li> [sqlite3_memory_used()]
1100** <li> [sqlite3_memory_highwater()]
1101** <li> [sqlite3_soft_heap_limit()]
drh0a60a382008-07-31 17:16:05 +00001102** <li> [sqlite3_status()]
drhce5a5a02008-06-10 17:41:44 +00001103** </ul>
1104** </dd>
drh33589792008-06-18 13:27:46 +00001105**
1106** <dt>SQLITE_CONFIG_SCRATCH</dt>
1107** <dd>This option specifies a static memory buffer that SQLite can use for
drh6860da02009-06-09 19:53:58 +00001108** scratch memory. There are three arguments: A pointer an 8-byte
1109** aligned memory buffer from which the scrach allocations will be
1110** drawn, the size of each scratch allocation (sz),
1111** and the maximum number of scratch allocations (N). The sz
drh0a60a382008-07-31 17:16:05 +00001112** argument must be a multiple of 16. The sz parameter should be a few bytes
drh6860da02009-06-09 19:53:58 +00001113** larger than the actual scratch space required due to internal overhead.
1114** The first argument should pointer to an 8-byte aligned buffer
1115** of at least sz*N bytes of memory.
drh33589792008-06-18 13:27:46 +00001116** SQLite will use no more than one scratch buffer at once per thread, so
mihailimdb4f2ad2008-06-21 11:20:48 +00001117** N should be set to the expected maximum number of threads. The sz
drh33589792008-06-18 13:27:46 +00001118** parameter should be 6 times the size of the largest database page size.
1119** Scratch buffers are used as part of the btree balance operation. If
1120** The btree balancer needs additional memory beyond what is provided by
1121** scratch buffers or if no scratch buffer space is specified, then SQLite
mihailimdb4f2ad2008-06-21 11:20:48 +00001122** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd>
drh33589792008-06-18 13:27:46 +00001123**
1124** <dt>SQLITE_CONFIG_PAGECACHE</dt>
1125** <dd>This option specifies a static memory buffer that SQLite can use for
drh21614742008-11-18 19:18:08 +00001126** the database page cache with the default page cache implemenation.
1127** This configuration should not be used if an application-define page
1128** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
drh6860da02009-06-09 19:53:58 +00001129** There are three arguments to this option: A pointer to 8-byte aligned
mihailimdb4f2ad2008-06-21 11:20:48 +00001130** memory, the size of each page buffer (sz), and the number of pages (N).
drh6860da02009-06-09 19:53:58 +00001131** The sz argument should be the size of the largest database page
1132** (a power of two between 512 and 32768) plus a little extra for each
1133** page header. The page header size is 20 to 40 bytes depending on
1134** the host architecture. It is harmless, apart from the wasted memory,
1135** to make sz a little too large. The first
drh0a60a382008-07-31 17:16:05 +00001136** argument should point to an allocation of at least sz*N bytes of memory.
mihailimdb4f2ad2008-06-21 11:20:48 +00001137** SQLite will use the memory provided by the first argument to satisfy its
1138** memory needs for the first N pages that it adds to cache. If additional
1139** page cache memory is needed beyond what is provided by this option, then
drh0a60a382008-07-31 17:16:05 +00001140** SQLite goes to [sqlite3_malloc()] for the additional storage space.
1141** The implementation might use one or more of the N buffers to hold
drh6860da02009-06-09 19:53:58 +00001142** memory accounting information. The pointer in the first argument must
1143** be aligned to an 8-byte boundary or subsequent behavior of SQLite
1144** will be undefined.</dd>
drh33589792008-06-18 13:27:46 +00001145**
1146** <dt>SQLITE_CONFIG_HEAP</dt>
1147** <dd>This option specifies a static memory buffer that SQLite will use
1148** for all of its dynamic memory allocation needs beyond those provided
1149** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
drh6860da02009-06-09 19:53:58 +00001150** There are three arguments: An 8-byte aligned pointer to the memory,
1151** the number of bytes in the memory buffer, and the minimum allocation size.
1152** If the first pointer (the memory pointer) is NULL, then SQLite reverts
drh8a42cbd2008-07-10 18:13:42 +00001153** to using its default memory allocator (the system malloc() implementation),
1154** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. If the
1155** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1156** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
drh39bf74a2009-06-09 18:02:10 +00001157** allocator is engaged to handle all of SQLites memory allocation needs.
1158** The first pointer (the memory pointer) must be aligned to an 8-byte
drh6860da02009-06-09 19:53:58 +00001159** boundary or subsequent behavior of SQLite will be undefined.</dd>
drh33589792008-06-18 13:27:46 +00001160**
1161** <dt>SQLITE_CONFIG_MUTEX</dt>
1162** <dd>This option takes a single argument which is a pointer to an
mihailimdb4f2ad2008-06-21 11:20:48 +00001163** instance of the [sqlite3_mutex_methods] structure. The argument specifies
drh33589792008-06-18 13:27:46 +00001164** alternative low-level mutex routines to be used in place
1165** the mutex routines built into SQLite.</dd>
1166**
drh584ff182008-07-14 18:38:17 +00001167** <dt>SQLITE_CONFIG_GETMUTEX</dt>
drh33589792008-06-18 13:27:46 +00001168** <dd>This option takes a single argument which is a pointer to an
1169** instance of the [sqlite3_mutex_methods] structure. The
1170** [sqlite3_mutex_methods]
1171** structure is filled with the currently defined mutex routines.
1172** This option can be used to overload the default mutex allocation
1173** routines with a wrapper used to track mutex usage for performance
1174** profiling or testing, for example.</dd>
drh633e6d52008-07-28 19:34:53 +00001175**
1176** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1177** <dd>This option takes two arguments that determine the default
drh6aa5f152009-08-19 15:57:07 +00001178** memory allocation lookaside optimization. The first argument is the
drh633e6d52008-07-28 19:34:53 +00001179** size of each lookaside buffer slot and the second is the number of
drh6aa5f152009-08-19 15:57:07 +00001180** slots allocated to each database connection. This option sets the
1181** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1182** verb to [sqlite3_db_config()] can be used to change the lookaside
1183** configuration on individual connections.</dd>
drh633e6d52008-07-28 19:34:53 +00001184**
drh21614742008-11-18 19:18:08 +00001185** <dt>SQLITE_CONFIG_PCACHE</dt>
1186** <dd>This option takes a single argument which is a pointer to
1187** an [sqlite3_pcache_methods] object. This object specifies the interface
1188** to a custom page cache implementation. SQLite makes a copy of the
1189** object and uses it for page cache memory allocations.</dd>
1190**
1191** <dt>SQLITE_CONFIG_GETPCACHE</dt>
1192** <dd>This option takes a single argument which is a pointer to an
1193** [sqlite3_pcache_methods] object. SQLite copies of the current
1194** page cache implementation into that object.</dd>
1195**
drh633e6d52008-07-28 19:34:53 +00001196** </dl>
mihailima3f64902008-06-21 13:35:56 +00001197*/
drh40257ff2008-06-13 18:24:27 +00001198#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
1199#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
1200#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
drhfec00ea2008-06-14 16:56:21 +00001201#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
drh33589792008-06-18 13:27:46 +00001202#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1203#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
1204#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
1205#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
1206#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
1207#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
1208#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
shane2479de32008-11-10 18:05:35 +00001209/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
drh633e6d52008-07-28 19:34:53 +00001210#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
danielk1977bc2ca9e2008-11-13 14:28:28 +00001211#define SQLITE_CONFIG_PCACHE 14 /* sqlite3_pcache_methods* */
1212#define SQLITE_CONFIG_GETPCACHE 15 /* sqlite3_pcache_methods* */
danielk19772d340812008-07-24 08:20:40 +00001213
drhe9d1c722008-08-04 20:13:26 +00001214/*
1215** CAPI3REF: Configuration Options {H10170} <S20000>
1216** EXPERIMENTAL
1217**
1218** These constants are the available integer configuration options that
1219** can be passed as the second argument to the [sqlite3_db_config()] interface.
1220**
1221** New configuration options may be added in future releases of SQLite.
1222** Existing configuration options might be discontinued. Applications
1223** should check the return code from [sqlite3_db_config()] to make sure that
1224** the call worked. The [sqlite3_db_config()] interface will return a
1225** non-zero [error code] if a discontinued or unsupported configuration option
1226** is invoked.
1227**
1228** <dl>
1229** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1230** <dd>This option takes three additional arguments that determine the
1231** [lookaside memory allocator] configuration for the [database connection].
1232** The first argument (the third parameter to [sqlite3_db_config()] is a
drh6aa5f152009-08-19 15:57:07 +00001233** pointer to an memory buffer to use for lookaside memory.
drh6860da02009-06-09 19:53:58 +00001234** The first argument may be NULL in which case SQLite will allocate the
1235** lookaside buffer itself using [sqlite3_malloc()]. The second argument is the
drhe9d1c722008-08-04 20:13:26 +00001236** size of each lookaside buffer slot and the third argument is the number of
1237** slots. The size of the buffer in the first argument must be greater than
drh6aa5f152009-08-19 15:57:07 +00001238** or equal to the product of the second and third arguments. The buffer
1239** must be aligned to an 8-byte boundary. If the second argument is not
1240** a multiple of 8, it is internally rounded down to the next smaller
1241** multiple of 8. See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
drhe9d1c722008-08-04 20:13:26 +00001242**
1243** </dl>
1244*/
1245#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
1246
drhce5a5a02008-06-10 17:41:44 +00001247
drh673299b2008-06-09 21:57:22 +00001248/*
drhb25f9d82008-07-23 15:40:06 +00001249** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
drh6ed48bf2007-06-14 20:57:18 +00001250**
drh33c1be32008-01-30 16:16:14 +00001251** The sqlite3_extended_result_codes() routine enables or disables the
mihailimefc8e8a2008-06-21 16:47:09 +00001252** [extended result codes] feature of SQLite. The extended result
1253** codes are disabled by default for historical compatibility considerations.
drh6ed48bf2007-06-14 20:57:18 +00001254**
drh8b39db12009-02-18 18:37:58 +00001255** Requirements:
1256** [H12201] [H12202]
drh4ac285a2006-09-15 07:28:50 +00001257*/
1258int sqlite3_extended_result_codes(sqlite3*, int onoff);
1259
1260/*
drh9cd29642008-07-23 00:52:55 +00001261** CAPI3REF: Last Insert Rowid {H12220} <S10700>
drh6ed48bf2007-06-14 20:57:18 +00001262**
drh33c1be32008-01-30 16:16:14 +00001263** Each entry in an SQLite table has a unique 64-bit signed
drh49c3d572008-12-15 22:51:38 +00001264** integer key called the [ROWID | "rowid"]. The rowid is always available
drhfddfa2d2007-12-05 18:05:16 +00001265** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
drh33c1be32008-01-30 16:16:14 +00001266** names are not also used by explicitly declared columns. If
drh49c3d572008-12-15 22:51:38 +00001267** the table has a column of type [INTEGER PRIMARY KEY] then that column
mlcreechb2799412008-03-07 03:20:31 +00001268** is another alias for the rowid.
drh6ed48bf2007-06-14 20:57:18 +00001269**
drh49c3d572008-12-15 22:51:38 +00001270** This routine returns the [rowid] of the most recent
drhf8cecda2008-10-10 23:48:25 +00001271** successful [INSERT] into the database from the [database connection]
1272** in the first argument. If no successful [INSERT]s
mihailimdb4f2ad2008-06-21 11:20:48 +00001273** have ever occurred on that database connection, zero is returned.
drh6ed48bf2007-06-14 20:57:18 +00001274**
drh49c3d572008-12-15 22:51:38 +00001275** If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
mihailimdb4f2ad2008-06-21 11:20:48 +00001276** row is returned by this routine as long as the trigger is running.
1277** But once the trigger terminates, the value returned by this routine
1278** reverts to the last value inserted before the trigger fired.
drhe30f4422007-08-21 16:15:55 +00001279**
drhf8cecda2008-10-10 23:48:25 +00001280** An [INSERT] that fails due to a constraint violation is not a
1281** successful [INSERT] and does not change the value returned by this
drh33c1be32008-01-30 16:16:14 +00001282** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
drhdc1d9f12007-10-27 16:25:16 +00001283** and INSERT OR ABORT make no changes to the return value of this
mihailimdb4f2ad2008-06-21 11:20:48 +00001284** routine when their insertion fails. When INSERT OR REPLACE
drhdc1d9f12007-10-27 16:25:16 +00001285** encounters a constraint violation, it does not fail. The
1286** INSERT continues to completion after deleting rows that caused
1287** the constraint problem so INSERT OR REPLACE will always change
mihailimdb4f2ad2008-06-21 11:20:48 +00001288** the return value of this interface.
drhdc1d9f12007-10-27 16:25:16 +00001289**
drhf8cecda2008-10-10 23:48:25 +00001290** For the purposes of this routine, an [INSERT] is considered to
drh33c1be32008-01-30 16:16:14 +00001291** be successful even if it is subsequently rolled back.
1292**
drh8b39db12009-02-18 18:37:58 +00001293** Requirements:
1294** [H12221] [H12223]
drh33c1be32008-01-30 16:16:14 +00001295**
drh8b39db12009-02-18 18:37:58 +00001296** If a separate thread performs a new [INSERT] on the same
1297** database connection while the [sqlite3_last_insert_rowid()]
1298** function is running and thus changes the last insert [rowid],
1299** then the value returned by [sqlite3_last_insert_rowid()] is
1300** unpredictable and might not equal either the old or the new
1301** last insert [rowid].
drhaf9ff332002-01-16 21:00:27 +00001302*/
drh6d2069d2007-08-14 01:58:53 +00001303sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
drhaf9ff332002-01-16 21:00:27 +00001304
drhc8d30ac2002-04-12 10:08:59 +00001305/*
drh9cd29642008-07-23 00:52:55 +00001306** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
drh6ed48bf2007-06-14 20:57:18 +00001307**
drh33c1be32008-01-30 16:16:14 +00001308** This function returns the number of database rows that were changed
drhfddfa2d2007-12-05 18:05:16 +00001309** or inserted or deleted by the most recently completed SQL statement
mihailimdb4f2ad2008-06-21 11:20:48 +00001310** on the [database connection] specified by the first parameter.
drhf8cecda2008-10-10 23:48:25 +00001311** Only changes that are directly specified by the [INSERT], [UPDATE],
1312** or [DELETE] statement are counted. Auxiliary changes caused by
danb6163092009-10-07 10:43:26 +00001313** triggers or [foreign key actions] are not counted. Use the
1314** [sqlite3_total_changes()] function to find the total number of changes
1315** including changes caused by triggers and foreign key actions.
drh6ed48bf2007-06-14 20:57:18 +00001316**
drhd9c20d72009-04-29 14:33:44 +00001317** Changes to a view that are simulated by an [INSTEAD OF trigger]
1318** are not counted. Only real table changes are counted.
1319**
mlcreechb2799412008-03-07 03:20:31 +00001320** A "row change" is a change to a single row of a single table
drh33c1be32008-01-30 16:16:14 +00001321** caused by an INSERT, DELETE, or UPDATE statement. Rows that
drhd9c20d72009-04-29 14:33:44 +00001322** are changed as side effects of [REPLACE] constraint resolution,
1323** rollback, ABORT processing, [DROP TABLE], or by any other
drh33c1be32008-01-30 16:16:14 +00001324** mechanisms do not count as direct row changes.
1325**
1326** A "trigger context" is a scope of execution that begins and
drhd9c20d72009-04-29 14:33:44 +00001327** ends with the script of a [CREATE TRIGGER | trigger].
1328** Most SQL statements are
drh33c1be32008-01-30 16:16:14 +00001329** evaluated outside of any trigger. This is the "top level"
1330** trigger context. If a trigger fires from the top level, a
1331** new trigger context is entered for the duration of that one
1332** trigger. Subtriggers create subcontexts for their duration.
1333**
1334** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
1335** not create a new trigger context.
1336**
1337** This function returns the number of direct row changes in the
1338** most recent INSERT, UPDATE, or DELETE statement within the same
1339** trigger context.
1340**
mihailimdb4f2ad2008-06-21 11:20:48 +00001341** Thus, when called from the top level, this function returns the
drh33c1be32008-01-30 16:16:14 +00001342** number of changes in the most recent INSERT, UPDATE, or DELETE
mihailimdb4f2ad2008-06-21 11:20:48 +00001343** that also occurred at the top level. Within the body of a trigger,
1344** the sqlite3_changes() interface can be called to find the number of
drh930cc582007-03-28 13:07:40 +00001345** changes in the most recently completed INSERT, UPDATE, or DELETE
drhf5befa02007-12-06 02:42:07 +00001346** statement within the body of the same trigger.
mihailimdb4f2ad2008-06-21 11:20:48 +00001347** However, the number returned does not include changes
1348** caused by subtriggers since those have their own context.
drhc8d30ac2002-04-12 10:08:59 +00001349**
drhd9c20d72009-04-29 14:33:44 +00001350** See also the [sqlite3_total_changes()] interface and the
1351** [count_changes pragma].
drhe30f4422007-08-21 16:15:55 +00001352**
drh8b39db12009-02-18 18:37:58 +00001353** Requirements:
1354** [H12241] [H12243]
drh33c1be32008-01-30 16:16:14 +00001355**
drh8b39db12009-02-18 18:37:58 +00001356** If a separate thread makes changes on the same database connection
1357** while [sqlite3_changes()] is running then the value returned
1358** is unpredictable and not meaningful.
drhc8d30ac2002-04-12 10:08:59 +00001359*/
danielk1977f9d64d22004-06-19 08:18:07 +00001360int sqlite3_changes(sqlite3*);
drhc8d30ac2002-04-12 10:08:59 +00001361
rdcf146a772004-02-25 22:51:06 +00001362/*
drh9cd29642008-07-23 00:52:55 +00001363** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
mihailimdb4f2ad2008-06-21 11:20:48 +00001364**
drhd9c20d72009-04-29 14:33:44 +00001365** This function returns the number of row changes caused by [INSERT],
1366** [UPDATE] or [DELETE] statements since the [database connection] was opened.
danb6163092009-10-07 10:43:26 +00001367** The count includes all changes from all [CREATE TRIGGER | trigger]
1368** contexts and changes made by [foreign key actions]. However,
drhd9c20d72009-04-29 14:33:44 +00001369** the count does not include changes used to implement [REPLACE] constraints,
1370** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
drh4fb08662009-05-22 01:02:26 +00001371** count does not include rows of views that fire an [INSTEAD OF trigger],
1372** though if the INSTEAD OF trigger makes changes of its own, those changes
1373** are counted.
mihailimdb4f2ad2008-06-21 11:20:48 +00001374** The changes are counted as soon as the statement that makes them is
1375** completed (when the statement handle is passed to [sqlite3_reset()] or
drh33c1be32008-01-30 16:16:14 +00001376** [sqlite3_finalize()]).
drh6ed48bf2007-06-14 20:57:18 +00001377**
drhd9c20d72009-04-29 14:33:44 +00001378** See also the [sqlite3_changes()] interface and the
1379** [count_changes pragma].
drh33c1be32008-01-30 16:16:14 +00001380**
drh8b39db12009-02-18 18:37:58 +00001381** Requirements:
1382** [H12261] [H12263]
mihailimdb4f2ad2008-06-21 11:20:48 +00001383**
drh8b39db12009-02-18 18:37:58 +00001384** If a separate thread makes changes on the same database connection
1385** while [sqlite3_total_changes()] is running then the value
1386** returned is unpredictable and not meaningful.
rdcf146a772004-02-25 22:51:06 +00001387*/
danielk1977b28af712004-06-21 06:50:26 +00001388int sqlite3_total_changes(sqlite3*);
1389
drh6ed48bf2007-06-14 20:57:18 +00001390/*
drh9cd29642008-07-23 00:52:55 +00001391** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
drh6ed48bf2007-06-14 20:57:18 +00001392**
drh33c1be32008-01-30 16:16:14 +00001393** This function causes any pending database operation to abort and
1394** return at its earliest opportunity. This routine is typically
mihailimebe796c2008-06-21 20:11:17 +00001395** called in response to a user action such as pressing "Cancel"
drh4c504392000-10-16 22:06:40 +00001396** or Ctrl-C where the user wants a long query operation to halt
1397** immediately.
drh930cc582007-03-28 13:07:40 +00001398**
drh33c1be32008-01-30 16:16:14 +00001399** It is safe to call this routine from a thread different from the
1400** thread that is currently running the database operation. But it
mihailimdb4f2ad2008-06-21 11:20:48 +00001401** is not safe to call this routine with a [database connection] that
drh871f6ca2007-08-14 18:03:14 +00001402** is closed or might close before sqlite3_interrupt() returns.
drh6ed48bf2007-06-14 20:57:18 +00001403**
mihailimdb4f2ad2008-06-21 11:20:48 +00001404** If an SQL operation is very nearly finished at the time when
1405** sqlite3_interrupt() is called, then it might not have an opportunity
1406** to be interrupted and might continue to completion.
1407**
1408** An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1409** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
1410** that is inside an explicit transaction, then the entire transaction
1411** will be rolled back automatically.
1412**
drhd2b68432009-04-20 12:31:46 +00001413** The sqlite3_interrupt(D) call is in effect until all currently running
1414** SQL statements on [database connection] D complete. Any new SQL statements
1415** that are started after the sqlite3_interrupt() call and before the
1416** running statements reaches zero are interrupted as if they had been
1417** running prior to the sqlite3_interrupt() call. New SQL statements
1418** that are started after the running statement count reaches zero are
1419** not effected by the sqlite3_interrupt().
1420** A call to sqlite3_interrupt(D) that occurs when there are no running
1421** SQL statements is a no-op and has no effect on SQL statements
1422** that are started after the sqlite3_interrupt() call returns.
drh33c1be32008-01-30 16:16:14 +00001423**
drh8b39db12009-02-18 18:37:58 +00001424** Requirements:
1425** [H12271] [H12272]
drh33c1be32008-01-30 16:16:14 +00001426**
drh8b39db12009-02-18 18:37:58 +00001427** If the database connection closes while [sqlite3_interrupt()]
1428** is running then bad things will likely happen.
drh4c504392000-10-16 22:06:40 +00001429*/
danielk1977f9d64d22004-06-19 08:18:07 +00001430void sqlite3_interrupt(sqlite3*);
drh4c504392000-10-16 22:06:40 +00001431
drh6ed48bf2007-06-14 20:57:18 +00001432/*
drh9cd29642008-07-23 00:52:55 +00001433** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
drh75897232000-05-29 14:26:00 +00001434**
drh709915d2009-04-28 04:46:41 +00001435** These routines are useful during command-line input to determine if the
1436** currently entered text seems to form a complete SQL statement or
drhf5befa02007-12-06 02:42:07 +00001437** if additional input is needed before sending the text into
drh709915d2009-04-28 04:46:41 +00001438** SQLite for parsing. These routines return 1 if the input string
drhfddfa2d2007-12-05 18:05:16 +00001439** appears to be a complete SQL statement. A statement is judged to be
drh709915d2009-04-28 04:46:41 +00001440** complete if it ends with a semicolon token and is not a prefix of a
1441** well-formed CREATE TRIGGER statement. Semicolons that are embedded within
drh33c1be32008-01-30 16:16:14 +00001442** string literals or quoted identifier names or comments are not
1443** independent tokens (they are part of the token in which they are
drh709915d2009-04-28 04:46:41 +00001444** embedded) and thus do not count as a statement terminator. Whitespace
1445** and comments that follow the final semicolon are ignored.
1446**
1447** These routines return 0 if the statement is incomplete. If a
1448** memory allocation fails, then SQLITE_NOMEM is returned.
drh33c1be32008-01-30 16:16:14 +00001449**
mihailimdb4f2ad2008-06-21 11:20:48 +00001450** These routines do not parse the SQL statements thus
1451** will not detect syntactically incorrect SQL.
drhfddfa2d2007-12-05 18:05:16 +00001452**
drh709915d2009-04-28 04:46:41 +00001453** If SQLite has not been initialized using [sqlite3_initialize()] prior
1454** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
1455** automatically by sqlite3_complete16(). If that initialization fails,
1456** then the return value from sqlite3_complete16() will be non-zero
1457** regardless of whether or not the input SQL is complete.
1458**
drh8b39db12009-02-18 18:37:58 +00001459** Requirements: [H10511] [H10512]
drh33c1be32008-01-30 16:16:14 +00001460**
drh8b39db12009-02-18 18:37:58 +00001461** The input to [sqlite3_complete()] must be a zero-terminated
1462** UTF-8 string.
drh33c1be32008-01-30 16:16:14 +00001463**
drh8b39db12009-02-18 18:37:58 +00001464** The input to [sqlite3_complete16()] must be a zero-terminated
1465** UTF-16 string in native byte order.
drh75897232000-05-29 14:26:00 +00001466*/
danielk19776f8a5032004-05-10 10:34:51 +00001467int sqlite3_complete(const char *sql);
danielk197761de0d12004-05-27 23:56:16 +00001468int sqlite3_complete16(const void *sql);
drh75897232000-05-29 14:26:00 +00001469
drh2dfbbca2000-07-28 14:32:48 +00001470/*
drh9cd29642008-07-23 00:52:55 +00001471** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
drh6ed48bf2007-06-14 20:57:18 +00001472**
mihailimdb4f2ad2008-06-21 11:20:48 +00001473** This routine sets a callback function that might be invoked whenever
1474** an attempt is made to open a database table that another thread
1475** or process has locked.
1476**
1477** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
1478** is returned immediately upon encountering the lock. If the busy callback
1479** is not NULL, then the callback will be invoked with two arguments.
1480**
1481** The first argument to the handler is a copy of the void* pointer which
1482** is the third argument to sqlite3_busy_handler(). The second argument to
1483** the handler callback is the number of times that the busy handler has
1484** been invoked for this locking event. If the
drh6ed48bf2007-06-14 20:57:18 +00001485** busy callback returns 0, then no additional attempts are made to
1486** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
drh33c1be32008-01-30 16:16:14 +00001487** If the callback returns non-zero, then another attempt
drhfddfa2d2007-12-05 18:05:16 +00001488** is made to open the database for reading and the cycle repeats.
drh2dfbbca2000-07-28 14:32:48 +00001489**
mihailimdb4f2ad2008-06-21 11:20:48 +00001490** The presence of a busy handler does not guarantee that it will be invoked
1491** when there is lock contention. If SQLite determines that invoking the busy
1492** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1493** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
drh86939b52007-01-10 12:54:51 +00001494** Consider a scenario where one process is holding a read lock that
1495** it is trying to promote to a reserved lock and
1496** a second process is holding a reserved lock that it is trying
1497** to promote to an exclusive lock. The first process cannot proceed
1498** because it is blocked by the second and the second process cannot
1499** proceed because it is blocked by the first. If both processes
drhf5befa02007-12-06 02:42:07 +00001500** invoke the busy handlers, neither will make any progress. Therefore,
drh6ed48bf2007-06-14 20:57:18 +00001501** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
drh86939b52007-01-10 12:54:51 +00001502** will induce the first process to release its read lock and allow
1503** the second process to proceed.
1504**
drh33c1be32008-01-30 16:16:14 +00001505** The default busy callback is NULL.
drh2dfbbca2000-07-28 14:32:48 +00001506**
drh33c1be32008-01-30 16:16:14 +00001507** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
drhfddfa2d2007-12-05 18:05:16 +00001508** when SQLite is in the middle of a large transaction where all the
drh33c1be32008-01-30 16:16:14 +00001509** changes will not fit into the in-memory cache. SQLite will
drh6ed48bf2007-06-14 20:57:18 +00001510** already hold a RESERVED lock on the database file, but it needs
1511** to promote this lock to EXCLUSIVE so that it can spill cache
1512** pages into the database file without harm to concurrent
drh33c1be32008-01-30 16:16:14 +00001513** readers. If it is unable to promote the lock, then the in-memory
drh6ed48bf2007-06-14 20:57:18 +00001514** cache will be left in an inconsistent state and so the error
1515** code is promoted from the relatively benign [SQLITE_BUSY] to
drh33c1be32008-01-30 16:16:14 +00001516** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion
1517** forces an automatic rollback of the changes. See the
mihailimdb4f2ad2008-06-21 11:20:48 +00001518** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
drh6ed48bf2007-06-14 20:57:18 +00001519** CorruptionFollowingBusyError</a> wiki page for a discussion of why
1520** this is important.
mihailimdb4f2ad2008-06-21 11:20:48 +00001521**
1522** There can only be a single busy handler defined for each
1523** [database connection]. Setting a new busy handler clears any
1524** previously set handler. Note that calling [sqlite3_busy_timeout()]
1525** will also set or clear the busy handler.
drhd677b3d2007-08-20 22:48:41 +00001526**
drhc8075422008-09-10 13:09:23 +00001527** The busy callback should not take any actions which modify the
1528** database connection that invoked the busy handler. Any such actions
1529** result in undefined behavior.
1530**
drh8b39db12009-02-18 18:37:58 +00001531** Requirements:
1532** [H12311] [H12312] [H12314] [H12316] [H12318]
drh33c1be32008-01-30 16:16:14 +00001533**
drh8b39db12009-02-18 18:37:58 +00001534** A busy handler must not close the database connection
1535** or [prepared statement] that invoked the busy handler.
drh2dfbbca2000-07-28 14:32:48 +00001536*/
danielk1977f9d64d22004-06-19 08:18:07 +00001537int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
drh2dfbbca2000-07-28 14:32:48 +00001538
1539/*
drhb25f9d82008-07-23 15:40:06 +00001540** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
drh6ed48bf2007-06-14 20:57:18 +00001541**
mihailimdb4f2ad2008-06-21 11:20:48 +00001542** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
1543** for a specified amount of time when a table is locked. The handler
1544** will sleep multiple times until at least "ms" milliseconds of sleeping
drh9a247912008-07-22 18:45:08 +00001545** have accumulated. {H12343} After "ms" milliseconds of sleeping,
mihailimdb4f2ad2008-06-21 11:20:48 +00001546** the handler returns 0 which causes [sqlite3_step()] to return
1547** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
drh2dfbbca2000-07-28 14:32:48 +00001548**
drh33c1be32008-01-30 16:16:14 +00001549** Calling this routine with an argument less than or equal to zero
drh2dfbbca2000-07-28 14:32:48 +00001550** turns off all busy handlers.
drh6ed48bf2007-06-14 20:57:18 +00001551**
mihailimdb4f2ad2008-06-21 11:20:48 +00001552** There can only be a single busy handler for a particular
1553** [database connection] any any given moment. If another busy handler
1554** was defined (using [sqlite3_busy_handler()]) prior to calling
drh6ed48bf2007-06-14 20:57:18 +00001555** this routine, that other busy handler is cleared.
drh33c1be32008-01-30 16:16:14 +00001556**
drh8b39db12009-02-18 18:37:58 +00001557** Requirements:
1558** [H12341] [H12343] [H12344]
drh2dfbbca2000-07-28 14:32:48 +00001559*/
danielk1977f9d64d22004-06-19 08:18:07 +00001560int sqlite3_busy_timeout(sqlite3*, int ms);
drh2dfbbca2000-07-28 14:32:48 +00001561
drhe3710332000-09-29 13:30:53 +00001562/*
drh9cd29642008-07-23 00:52:55 +00001563** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
drh6ed48bf2007-06-14 20:57:18 +00001564**
drh33c1be32008-01-30 16:16:14 +00001565** Definition: A <b>result table</b> is memory data structure created by the
1566** [sqlite3_get_table()] interface. A result table records the
1567** complete query results from one or more queries.
drha18c5682000-10-08 22:20:57 +00001568**
drh33c1be32008-01-30 16:16:14 +00001569** The table conceptually has a number of rows and columns. But
1570** these numbers are not part of the result table itself. These
1571** numbers are obtained separately. Let N be the number of rows
1572** and M be the number of columns.
1573**
mihailimdb4f2ad2008-06-21 11:20:48 +00001574** A result table is an array of pointers to zero-terminated UTF-8 strings.
1575** There are (N+1)*M elements in the array. The first M pointers point
1576** to zero-terminated strings that contain the names of the columns.
1577** The remaining entries all point to query results. NULL values result
1578** in NULL pointers. All other values are in their UTF-8 zero-terminated
1579** string representation as returned by [sqlite3_column_text()].
drh33c1be32008-01-30 16:16:14 +00001580**
mihailimdb4f2ad2008-06-21 11:20:48 +00001581** A result table might consist of one or more memory allocations.
drh33c1be32008-01-30 16:16:14 +00001582** It is not safe to pass a result table directly to [sqlite3_free()].
1583** A result table should be deallocated using [sqlite3_free_table()].
1584**
1585** As an example of the result table format, suppose a query result
1586** is as follows:
drha18c5682000-10-08 22:20:57 +00001587**
drh8bacf972007-08-25 16:21:29 +00001588** <blockquote><pre>
drha18c5682000-10-08 22:20:57 +00001589** Name | Age
1590** -----------------------
1591** Alice | 43
1592** Bob | 28
1593** Cindy | 21
drh8bacf972007-08-25 16:21:29 +00001594** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001595**
drh33c1be32008-01-30 16:16:14 +00001596** There are two column (M==2) and three rows (N==3). Thus the
1597** result table has 8 entries. Suppose the result table is stored
1598** in an array names azResult. Then azResult holds this content:
drha18c5682000-10-08 22:20:57 +00001599**
drh8bacf972007-08-25 16:21:29 +00001600** <blockquote><pre>
1601** azResult&#91;0] = "Name";
1602** azResult&#91;1] = "Age";
1603** azResult&#91;2] = "Alice";
1604** azResult&#91;3] = "43";
1605** azResult&#91;4] = "Bob";
1606** azResult&#91;5] = "28";
1607** azResult&#91;6] = "Cindy";
1608** azResult&#91;7] = "21";
1609** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001610**
drh33c1be32008-01-30 16:16:14 +00001611** The sqlite3_get_table() function evaluates one or more
1612** semicolon-separated SQL statements in the zero-terminated UTF-8
1613** string of its 2nd parameter. It returns a result table to the
1614** pointer given in its 3rd parameter.
drha18c5682000-10-08 22:20:57 +00001615**
mihailimdb4f2ad2008-06-21 11:20:48 +00001616** After the calling function has finished using the result, it should
1617** pass the pointer to the result table to sqlite3_free_table() in order to
1618** release the memory that was malloced. Because of the way the
drh33c1be32008-01-30 16:16:14 +00001619** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
mihailimdb4f2ad2008-06-21 11:20:48 +00001620** function must not try to call [sqlite3_free()] directly. Only
drh33c1be32008-01-30 16:16:14 +00001621** [sqlite3_free_table()] is able to release the memory properly and safely.
drhe3710332000-09-29 13:30:53 +00001622**
drh33c1be32008-01-30 16:16:14 +00001623** The sqlite3_get_table() interface is implemented as a wrapper around
1624** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
1625** to any internal data structures of SQLite. It uses only the public
1626** interface defined here. As a consequence, errors that occur in the
1627** wrapper layer outside of the internal [sqlite3_exec()] call are not
mihailimdb4f2ad2008-06-21 11:20:48 +00001628** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()].
drh33c1be32008-01-30 16:16:14 +00001629**
drh8b39db12009-02-18 18:37:58 +00001630** Requirements:
1631** [H12371] [H12373] [H12374] [H12376] [H12379] [H12382]
drhe3710332000-09-29 13:30:53 +00001632*/
danielk19776f8a5032004-05-10 10:34:51 +00001633int sqlite3_get_table(
drhcf538f42008-06-27 14:51:52 +00001634 sqlite3 *db, /* An open database */
1635 const char *zSql, /* SQL to be evaluated */
1636 char ***pazResult, /* Results of the query */
1637 int *pnRow, /* Number of result rows written here */
1638 int *pnColumn, /* Number of result columns written here */
1639 char **pzErrmsg /* Error msg written here */
drhe3710332000-09-29 13:30:53 +00001640);
danielk19776f8a5032004-05-10 10:34:51 +00001641void sqlite3_free_table(char **result);
drhe3710332000-09-29 13:30:53 +00001642
drha18c5682000-10-08 22:20:57 +00001643/*
drh9cd29642008-07-23 00:52:55 +00001644** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
drh6ed48bf2007-06-14 20:57:18 +00001645**
shane7c7c3112009-08-17 15:31:23 +00001646** These routines are work-alikes of the "printf()" family of functions
drh6ed48bf2007-06-14 20:57:18 +00001647** from the standard C library.
1648**
drh33c1be32008-01-30 16:16:14 +00001649** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
drh6d2069d2007-08-14 01:58:53 +00001650** results into memory obtained from [sqlite3_malloc()].
drh33c1be32008-01-30 16:16:14 +00001651** The strings returned by these two routines should be
mihailim04bcc002008-06-22 10:21:27 +00001652** released by [sqlite3_free()]. Both routines return a
drh6ed48bf2007-06-14 20:57:18 +00001653** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1654** memory to hold the resulting string.
1655**
drh33c1be32008-01-30 16:16:14 +00001656** In sqlite3_snprintf() routine is similar to "snprintf()" from
drh6ed48bf2007-06-14 20:57:18 +00001657** the standard C library. The result is written into the
1658** buffer supplied as the second parameter whose size is given by
drh33c1be32008-01-30 16:16:14 +00001659** the first parameter. Note that the order of the
drh6ed48bf2007-06-14 20:57:18 +00001660** first two parameters is reversed from snprintf(). This is an
1661** historical accident that cannot be fixed without breaking
drh33c1be32008-01-30 16:16:14 +00001662** backwards compatibility. Note also that sqlite3_snprintf()
drh6ed48bf2007-06-14 20:57:18 +00001663** returns a pointer to its buffer instead of the number of
drh33c1be32008-01-30 16:16:14 +00001664** characters actually written into the buffer. We admit that
drh6ed48bf2007-06-14 20:57:18 +00001665** the number of characters written would be a more useful return
1666** value but we cannot change the implementation of sqlite3_snprintf()
1667** now without breaking compatibility.
1668**
drh33c1be32008-01-30 16:16:14 +00001669** As long as the buffer size is greater than zero, sqlite3_snprintf()
1670** guarantees that the buffer is always zero-terminated. The first
drh6ed48bf2007-06-14 20:57:18 +00001671** parameter "n" is the total size of the buffer, including space for
drh33c1be32008-01-30 16:16:14 +00001672** the zero terminator. So the longest string that can be completely
drh6ed48bf2007-06-14 20:57:18 +00001673** written will be n-1 characters.
1674**
1675** These routines all implement some additional formatting
drh4f26d6c2004-05-26 23:25:30 +00001676** options that are useful for constructing SQL statements.
shane26b34032008-05-23 17:21:09 +00001677** All of the usual printf() formatting options apply. In addition, there
drh153c62c2007-08-24 03:51:33 +00001678** is are "%q", "%Q", and "%z" options.
drh6ed48bf2007-06-14 20:57:18 +00001679**
drh33c1be32008-01-30 16:16:14 +00001680** The %q option works like %s in that it substitutes a null-terminated
drh66b89c82000-11-28 20:47:17 +00001681** string from the argument list. But %q also doubles every '\'' character.
drh33c1be32008-01-30 16:16:14 +00001682** %q is designed for use inside a string literal. By doubling each '\''
drh66b89c82000-11-28 20:47:17 +00001683** character it escapes that character and allows it to be inserted into
drha18c5682000-10-08 22:20:57 +00001684** the string.
1685**
mihailimdb4f2ad2008-06-21 11:20:48 +00001686** For example, assume the string variable zText contains text as follows:
drha18c5682000-10-08 22:20:57 +00001687**
drh6ed48bf2007-06-14 20:57:18 +00001688** <blockquote><pre>
1689** char *zText = "It's a happy day!";
1690** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001691**
drh6ed48bf2007-06-14 20:57:18 +00001692** One can use this text in an SQL statement as follows:
drha18c5682000-10-08 22:20:57 +00001693**
drh6ed48bf2007-06-14 20:57:18 +00001694** <blockquote><pre>
1695** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1696** sqlite3_exec(db, zSQL, 0, 0, 0);
1697** sqlite3_free(zSQL);
1698** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001699**
1700** Because the %q format string is used, the '\'' character in zText
1701** is escaped and the SQL generated is as follows:
1702**
drh6ed48bf2007-06-14 20:57:18 +00001703** <blockquote><pre>
1704** INSERT INTO table1 VALUES('It''s a happy day!')
1705** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001706**
1707** This is correct. Had we used %s instead of %q, the generated SQL
1708** would have looked like this:
1709**
drh6ed48bf2007-06-14 20:57:18 +00001710** <blockquote><pre>
1711** INSERT INTO table1 VALUES('It's a happy day!');
1712** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001713**
mihailimdb4f2ad2008-06-21 11:20:48 +00001714** This second example is an SQL syntax error. As a general rule you should
1715** always use %q instead of %s when inserting text into a string literal.
drh6ed48bf2007-06-14 20:57:18 +00001716**
drh33c1be32008-01-30 16:16:14 +00001717** The %Q option works like %q except it also adds single quotes around
mihailimdb4f2ad2008-06-21 11:20:48 +00001718** the outside of the total string. Additionally, if the parameter in the
1719** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
mihailim04bcc002008-06-22 10:21:27 +00001720** single quotes) in place of the %Q option. So, for example, one could say:
drh6ed48bf2007-06-14 20:57:18 +00001721**
1722** <blockquote><pre>
1723** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1724** sqlite3_exec(db, zSQL, 0, 0, 0);
1725** sqlite3_free(zSQL);
1726** </pre></blockquote>
1727**
1728** The code above will render a correct SQL statement in the zSQL
1729** variable even if the zText variable is a NULL pointer.
drh153c62c2007-08-24 03:51:33 +00001730**
drh33c1be32008-01-30 16:16:14 +00001731** The "%z" formatting option works exactly like "%s" with the
drh153c62c2007-08-24 03:51:33 +00001732** addition that after the string has been read and copied into
drhfddfa2d2007-12-05 18:05:16 +00001733** the result, [sqlite3_free()] is called on the input string. {END}
drh33c1be32008-01-30 16:16:14 +00001734**
drh8b39db12009-02-18 18:37:58 +00001735** Requirements:
1736** [H17403] [H17406] [H17407]
drha18c5682000-10-08 22:20:57 +00001737*/
danielk19776f8a5032004-05-10 10:34:51 +00001738char *sqlite3_mprintf(const char*,...);
1739char *sqlite3_vmprintf(const char*, va_list);
drhfeac5f82004-08-01 00:10:45 +00001740char *sqlite3_snprintf(int,char*,const char*, ...);
drh5191b7e2002-03-08 02:12:00 +00001741
drh28dd4792006-06-26 21:35:44 +00001742/*
drh9cd29642008-07-23 00:52:55 +00001743** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
drhd84f9462007-08-15 11:28:56 +00001744**
drh33c1be32008-01-30 16:16:14 +00001745** The SQLite core uses these three routines for all of its own
1746** internal memory allocation needs. "Core" in the previous sentence
drhf5befa02007-12-06 02:42:07 +00001747** does not include operating-system specific VFS implementation. The
shane26b34032008-05-23 17:21:09 +00001748** Windows VFS uses native malloc() and free() for some operations.
drhd64621d2007-11-05 17:54:17 +00001749**
drh33c1be32008-01-30 16:16:14 +00001750** The sqlite3_malloc() routine returns a pointer to a block
drhfddfa2d2007-12-05 18:05:16 +00001751** of memory at least N bytes in length, where N is the parameter.
drh33c1be32008-01-30 16:16:14 +00001752** If sqlite3_malloc() is unable to obtain sufficient free
1753** memory, it returns a NULL pointer. If the parameter N to
drhfddfa2d2007-12-05 18:05:16 +00001754** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
1755** a NULL pointer.
1756**
drh33c1be32008-01-30 16:16:14 +00001757** Calling sqlite3_free() with a pointer previously returned
drhfddfa2d2007-12-05 18:05:16 +00001758** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
drh33c1be32008-01-30 16:16:14 +00001759** that it might be reused. The sqlite3_free() routine is
drhfddfa2d2007-12-05 18:05:16 +00001760** a no-op if is called with a NULL pointer. Passing a NULL pointer
drh33c1be32008-01-30 16:16:14 +00001761** to sqlite3_free() is harmless. After being freed, memory
drhfddfa2d2007-12-05 18:05:16 +00001762** should neither be read nor written. Even reading previously freed
1763** memory might result in a segmentation fault or other severe error.
drh33c1be32008-01-30 16:16:14 +00001764** Memory corruption, a segmentation fault, or other severe error
drhfddfa2d2007-12-05 18:05:16 +00001765** might result if sqlite3_free() is called with a non-NULL pointer that
drh7b228b32008-10-17 15:10:37 +00001766** was not obtained from sqlite3_malloc() or sqlite3_realloc().
drhfddfa2d2007-12-05 18:05:16 +00001767**
drh33c1be32008-01-30 16:16:14 +00001768** The sqlite3_realloc() interface attempts to resize a
drhfddfa2d2007-12-05 18:05:16 +00001769** prior memory allocation to be at least N bytes, where N is the
1770** second parameter. The memory allocation to be resized is the first
drh33c1be32008-01-30 16:16:14 +00001771** parameter. If the first parameter to sqlite3_realloc()
drhfddfa2d2007-12-05 18:05:16 +00001772** is a NULL pointer then its behavior is identical to calling
1773** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
drh33c1be32008-01-30 16:16:14 +00001774** If the second parameter to sqlite3_realloc() is zero or
drhfddfa2d2007-12-05 18:05:16 +00001775** negative then the behavior is exactly the same as calling
1776** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
mihailimdb4f2ad2008-06-21 11:20:48 +00001777** sqlite3_realloc() returns a pointer to a memory allocation
drhfddfa2d2007-12-05 18:05:16 +00001778** of at least N bytes in size or NULL if sufficient memory is unavailable.
drh33c1be32008-01-30 16:16:14 +00001779** If M is the size of the prior allocation, then min(N,M) bytes
drhfddfa2d2007-12-05 18:05:16 +00001780** of the prior allocation are copied into the beginning of buffer returned
1781** by sqlite3_realloc() and the prior allocation is freed.
drh33c1be32008-01-30 16:16:14 +00001782** If sqlite3_realloc() returns NULL, then the prior allocation
drhfddfa2d2007-12-05 18:05:16 +00001783** is not freed.
1784**
drh33c1be32008-01-30 16:16:14 +00001785** The memory returned by sqlite3_malloc() and sqlite3_realloc()
drhf5befa02007-12-06 02:42:07 +00001786** is always aligned to at least an 8 byte boundary. {END}
1787**
mihailimdb4f2ad2008-06-21 11:20:48 +00001788** The default implementation of the memory allocation subsystem uses
1789** the malloc(), realloc() and free() provided by the standard C library.
drh9a247912008-07-22 18:45:08 +00001790** {H17382} However, if SQLite is compiled with the
mihailimdb4f2ad2008-06-21 11:20:48 +00001791** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i>
1792** is an integer), then SQLite create a static array of at least
1793** <i>NNN</i> bytes in size and uses that array for all of its dynamic
1794** memory allocation needs. {END} Additional memory allocator options
1795** may be added in future releases.
drhd64621d2007-11-05 17:54:17 +00001796**
1797** In SQLite version 3.5.0 and 3.5.1, it was possible to define
1798** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
1799** implementation of these routines to be omitted. That capability
mihailimdb4f2ad2008-06-21 11:20:48 +00001800** is no longer provided. Only built-in memory allocators can be used.
drh8bacf972007-08-25 16:21:29 +00001801**
shane26b34032008-05-23 17:21:09 +00001802** The Windows OS interface layer calls
drh8bacf972007-08-25 16:21:29 +00001803** the system malloc() and free() directly when converting
1804** filenames between the UTF-8 encoding used by SQLite
shane26b34032008-05-23 17:21:09 +00001805** and whatever filename encoding is used by the particular Windows
drh8bacf972007-08-25 16:21:29 +00001806** installation. Memory allocation errors are detected, but
1807** they are reported back as [SQLITE_CANTOPEN] or
1808** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
drh33c1be32008-01-30 16:16:14 +00001809**
drh8b39db12009-02-18 18:37:58 +00001810** Requirements:
1811** [H17303] [H17304] [H17305] [H17306] [H17310] [H17312] [H17315] [H17318]
1812** [H17321] [H17322] [H17323]
drh33c1be32008-01-30 16:16:14 +00001813**
drh8b39db12009-02-18 18:37:58 +00001814** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
1815** must be either NULL or else pointers obtained from a prior
1816** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
1817** not yet been released.
drh33c1be32008-01-30 16:16:14 +00001818**
drh8b39db12009-02-18 18:37:58 +00001819** The application must not read or write any part of
1820** a block of memory after it has been released using
1821** [sqlite3_free()] or [sqlite3_realloc()].
drh28dd4792006-06-26 21:35:44 +00001822*/
drhf3a65f72007-08-22 20:18:21 +00001823void *sqlite3_malloc(int);
1824void *sqlite3_realloc(void*, int);
drh28dd4792006-06-26 21:35:44 +00001825void sqlite3_free(void*);
1826
drh5191b7e2002-03-08 02:12:00 +00001827/*
drh9cd29642008-07-23 00:52:55 +00001828** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
drhd84f9462007-08-15 11:28:56 +00001829**
drh33c1be32008-01-30 16:16:14 +00001830** SQLite provides these two interfaces for reporting on the status
1831** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
mihailimdb4f2ad2008-06-21 11:20:48 +00001832** routines, which form the built-in memory allocation subsystem.
drhd84f9462007-08-15 11:28:56 +00001833**
drh8b39db12009-02-18 18:37:58 +00001834** Requirements:
1835** [H17371] [H17373] [H17374] [H17375]
drhd84f9462007-08-15 11:28:56 +00001836*/
drh153c62c2007-08-24 03:51:33 +00001837sqlite3_int64 sqlite3_memory_used(void);
1838sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
drhd84f9462007-08-15 11:28:56 +00001839
1840/*
drh9cd29642008-07-23 00:52:55 +00001841** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
drh2fa18682008-03-19 14:15:34 +00001842**
1843** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
drh49c3d572008-12-15 22:51:38 +00001844** select random [ROWID | ROWIDs] when inserting new records into a table that
1845** already uses the largest possible [ROWID]. The PRNG is also used for
drh2fa18682008-03-19 14:15:34 +00001846** the build-in random() and randomblob() SQL functions. This interface allows
shane26b34032008-05-23 17:21:09 +00001847** applications to access the same PRNG for other purposes.
drh2fa18682008-03-19 14:15:34 +00001848**
1849** A call to this routine stores N bytes of randomness into buffer P.
1850**
1851** The first time this routine is invoked (either internally or by
1852** the application) the PRNG is seeded using randomness obtained
1853** from the xRandomness method of the default [sqlite3_vfs] object.
1854** On all subsequent invocations, the pseudo-randomness is generated
1855** internally and without recourse to the [sqlite3_vfs] xRandomness
1856** method.
1857**
drh8b39db12009-02-18 18:37:58 +00001858** Requirements:
1859** [H17392]
drh2fa18682008-03-19 14:15:34 +00001860*/
1861void sqlite3_randomness(int N, void *P);
1862
1863/*
drh9cd29642008-07-23 00:52:55 +00001864** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
drhfddfa2d2007-12-05 18:05:16 +00001865**
drh33c1be32008-01-30 16:16:14 +00001866** This routine registers a authorizer callback with a particular
drhf47ce562008-03-20 18:00:49 +00001867** [database connection], supplied in the first argument.
drh6ed48bf2007-06-14 20:57:18 +00001868** The authorizer callback is invoked as SQL statements are being compiled
1869** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
drh33c1be32008-01-30 16:16:14 +00001870** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various
drh6ed48bf2007-06-14 20:57:18 +00001871** points during the compilation process, as logic is being created
1872** to perform various actions, the authorizer callback is invoked to
drhf5befa02007-12-06 02:42:07 +00001873** see if those actions are allowed. The authorizer callback should
drhf47ce562008-03-20 18:00:49 +00001874** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
drh6ed48bf2007-06-14 20:57:18 +00001875** specific action but allow the SQL statement to continue to be
1876** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
mihailima3f64902008-06-21 13:35:56 +00001877** rejected with an error. If the authorizer callback returns
drhf5befa02007-12-06 02:42:07 +00001878** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
mihailima3f64902008-06-21 13:35:56 +00001879** then the [sqlite3_prepare_v2()] or equivalent call that triggered
drh33c1be32008-01-30 16:16:14 +00001880** the authorizer will fail with an error message.
drh6ed48bf2007-06-14 20:57:18 +00001881**
drhf5befa02007-12-06 02:42:07 +00001882** When the callback returns [SQLITE_OK], that means the operation
drh33c1be32008-01-30 16:16:14 +00001883** requested is ok. When the callback returns [SQLITE_DENY], the
drhf5befa02007-12-06 02:42:07 +00001884** [sqlite3_prepare_v2()] or equivalent call that triggered the
drh33c1be32008-01-30 16:16:14 +00001885** authorizer will fail with an error message explaining that
drh959b5302009-04-30 15:59:56 +00001886** access is denied.
drh6ed48bf2007-06-14 20:57:18 +00001887**
mihailima3f64902008-06-21 13:35:56 +00001888** The first parameter to the authorizer callback is a copy of the third
1889** parameter to the sqlite3_set_authorizer() interface. The second parameter
1890** to the callback is an integer [SQLITE_COPY | action code] that specifies
1891** the particular action to be authorized. The third through sixth parameters
1892** to the callback are zero-terminated strings that contain additional
1893** details about the action to be authorized.
drh6ed48bf2007-06-14 20:57:18 +00001894**
drh959b5302009-04-30 15:59:56 +00001895** If the action code is [SQLITE_READ]
1896** and the callback returns [SQLITE_IGNORE] then the
1897** [prepared statement] statement is constructed to substitute
1898** a NULL value in place of the table column that would have
1899** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
1900** return can be used to deny an untrusted user access to individual
1901** columns of a table.
1902** If the action code is [SQLITE_DELETE] and the callback returns
1903** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
1904** [truncate optimization] is disabled and all rows are deleted individually.
1905**
drhf47ce562008-03-20 18:00:49 +00001906** An authorizer is used when [sqlite3_prepare | preparing]
mihailimebe796c2008-06-21 20:11:17 +00001907** SQL statements from an untrusted source, to ensure that the SQL statements
1908** do not try to access data they are not allowed to see, or that they do not
1909** try to execute malicious statements that damage the database. For
drh6ed48bf2007-06-14 20:57:18 +00001910** example, an application may allow a user to enter arbitrary
1911** SQL queries for evaluation by a database. But the application does
1912** not want the user to be able to make arbitrary changes to the
1913** database. An authorizer could then be put in place while the
drhf47ce562008-03-20 18:00:49 +00001914** user-entered SQL is being [sqlite3_prepare | prepared] that
1915** disallows everything except [SELECT] statements.
1916**
1917** Applications that need to process SQL from untrusted sources
1918** might also consider lowering resource limits using [sqlite3_limit()]
1919** and limiting database size using the [max_page_count] [PRAGMA]
1920** in addition to using an authorizer.
drh6ed48bf2007-06-14 20:57:18 +00001921**
drh33c1be32008-01-30 16:16:14 +00001922** Only a single authorizer can be in place on a database connection
drh6ed48bf2007-06-14 20:57:18 +00001923** at a time. Each call to sqlite3_set_authorizer overrides the
drh33c1be32008-01-30 16:16:14 +00001924** previous call. Disable the authorizer by installing a NULL callback.
1925** The authorizer is disabled by default.
drh6ed48bf2007-06-14 20:57:18 +00001926**
drhc8075422008-09-10 13:09:23 +00001927** The authorizer callback must not do anything that will modify
1928** the database connection that invoked the authorizer callback.
1929** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
1930** database connections for the meaning of "modify" in this paragraph.
1931**
drh7b37c5d2008-08-12 14:51:29 +00001932** When [sqlite3_prepare_v2()] is used to prepare a statement, the
shane7c7c3112009-08-17 15:31:23 +00001933** statement might be re-prepared during [sqlite3_step()] due to a
drh7b37c5d2008-08-12 14:51:29 +00001934** schema change. Hence, the application should ensure that the
1935** correct authorizer callback remains in place during the [sqlite3_step()].
1936**
mihailima3f64902008-06-21 13:35:56 +00001937** Note that the authorizer callback is invoked only during
drh33c1be32008-01-30 16:16:14 +00001938** [sqlite3_prepare()] or its variants. Authorization is not
drh959b5302009-04-30 15:59:56 +00001939** performed during statement evaluation in [sqlite3_step()], unless
1940** as stated in the previous paragraph, sqlite3_step() invokes
1941** sqlite3_prepare_v2() to reprepare a statement after a schema change.
drh33c1be32008-01-30 16:16:14 +00001942**
drh8b39db12009-02-18 18:37:58 +00001943** Requirements:
1944** [H12501] [H12502] [H12503] [H12504] [H12505] [H12506] [H12507] [H12510]
1945** [H12511] [H12512] [H12520] [H12521] [H12522]
drhed6c8672003-01-12 18:02:16 +00001946*/
danielk19776f8a5032004-05-10 10:34:51 +00001947int sqlite3_set_authorizer(
danielk1977f9d64d22004-06-19 08:18:07 +00001948 sqlite3*,
drhe22a3342003-04-22 20:30:37 +00001949 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
drhe5f9c642003-01-13 23:27:31 +00001950 void *pUserData
drhed6c8672003-01-12 18:02:16 +00001951);
1952
1953/*
drh9cd29642008-07-23 00:52:55 +00001954** CAPI3REF: Authorizer Return Codes {H12590} <H12500>
drh6ed48bf2007-06-14 20:57:18 +00001955**
1956** The [sqlite3_set_authorizer | authorizer callback function] must
1957** return either [SQLITE_OK] or one of these two constants in order
1958** to signal SQLite whether or not the action is permitted. See the
1959** [sqlite3_set_authorizer | authorizer documentation] for additional
1960** information.
1961*/
1962#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
1963#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
1964
1965/*
drh9cd29642008-07-23 00:52:55 +00001966** CAPI3REF: Authorizer Action Codes {H12550} <H12500>
drh6ed48bf2007-06-14 20:57:18 +00001967**
1968** The [sqlite3_set_authorizer()] interface registers a callback function
mihailima3f64902008-06-21 13:35:56 +00001969** that is invoked to authorize certain SQL statement actions. The
drh6ed48bf2007-06-14 20:57:18 +00001970** second parameter to the callback is an integer code that specifies
1971** what action is being authorized. These are the integer action codes that
drh33c1be32008-01-30 16:16:14 +00001972** the authorizer callback may be passed.
drh6ed48bf2007-06-14 20:57:18 +00001973**
mihailima3f64902008-06-21 13:35:56 +00001974** These action code values signify what kind of operation is to be
drh33c1be32008-01-30 16:16:14 +00001975** authorized. The 3rd and 4th parameters to the authorization
drhf5befa02007-12-06 02:42:07 +00001976** callback function will be parameters or NULL depending on which of these
drh33c1be32008-01-30 16:16:14 +00001977** codes is used as the second parameter. The 5th parameter to the
mihailima3f64902008-06-21 13:35:56 +00001978** authorizer callback is the name of the database ("main", "temp",
drh33c1be32008-01-30 16:16:14 +00001979** etc.) if applicable. The 6th parameter to the authorizer callback
drh5cf590c2003-04-24 01:45:04 +00001980** is the name of the inner-most trigger or view that is responsible for
mihailima3f64902008-06-21 13:35:56 +00001981** the access attempt or NULL if this access attempt is directly from
drh6ed48bf2007-06-14 20:57:18 +00001982** top-level SQL code.
drh33c1be32008-01-30 16:16:14 +00001983**
drh8b39db12009-02-18 18:37:58 +00001984** Requirements:
1985** [H12551] [H12552] [H12553] [H12554]
drhed6c8672003-01-12 18:02:16 +00001986*/
drh6ed48bf2007-06-14 20:57:18 +00001987/******************************************* 3rd ************ 4th ***********/
drhe5f9c642003-01-13 23:27:31 +00001988#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
1989#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
1990#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
1991#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00001992#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00001993#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
drh77ad4e42003-01-14 02:49:27 +00001994#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00001995#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
1996#define SQLITE_DELETE 9 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00001997#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00001998#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00001999#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002000#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002001#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002002#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002003#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002004#define SQLITE_DROP_VIEW 17 /* View Name NULL */
2005#define SQLITE_INSERT 18 /* Table Name NULL */
2006#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
2007#define SQLITE_READ 20 /* Table Name Column Name */
2008#define SQLITE_SELECT 21 /* NULL NULL */
danielk1977ab9b7032008-12-30 06:24:58 +00002009#define SQLITE_TRANSACTION 22 /* Operation NULL */
drhe5f9c642003-01-13 23:27:31 +00002010#define SQLITE_UPDATE 23 /* Table Name Column Name */
drh81e293b2003-06-06 19:00:42 +00002011#define SQLITE_ATTACH 24 /* Filename NULL */
2012#define SQLITE_DETACH 25 /* Database Name NULL */
danielk19771c8c23c2004-11-12 15:53:37 +00002013#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
danielk19771d54df82004-11-23 15:41:16 +00002014#define SQLITE_REINDEX 27 /* Index Name NULL */
drhe6e04962005-07-23 02:17:03 +00002015#define SQLITE_ANALYZE 28 /* Table Name NULL */
danielk1977f1a381e2006-06-16 08:01:02 +00002016#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
2017#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
drh2e904c52008-11-10 23:54:05 +00002018#define SQLITE_FUNCTION 31 /* NULL Function Name */
danielk1977ab9b7032008-12-30 06:24:58 +00002019#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
drh6ed48bf2007-06-14 20:57:18 +00002020#define SQLITE_COPY 0 /* No longer used */
drhed6c8672003-01-12 18:02:16 +00002021
2022/*
drh9cd29642008-07-23 00:52:55 +00002023** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400>
drhd5a68d32008-08-04 13:44:57 +00002024** EXPERIMENTAL
drh6ed48bf2007-06-14 20:57:18 +00002025**
2026** These routines register callback functions that can be used for
2027** tracing and profiling the execution of SQL statements.
drhfddfa2d2007-12-05 18:05:16 +00002028**
drh33c1be32008-01-30 16:16:14 +00002029** The callback function registered by sqlite3_trace() is invoked at
2030** various times when an SQL statement is being run by [sqlite3_step()].
2031** The callback returns a UTF-8 rendering of the SQL statement text
2032** as the statement first begins executing. Additional callbacks occur
shane26b34032008-05-23 17:21:09 +00002033** as each triggered subprogram is entered. The callbacks for triggers
drh33c1be32008-01-30 16:16:14 +00002034** contain a UTF-8 SQL comment that identifies the trigger.
mihailima3f64902008-06-21 13:35:56 +00002035**
drh33c1be32008-01-30 16:16:14 +00002036** The callback function registered by sqlite3_profile() is invoked
2037** as each SQL statement finishes. The profile callback contains
2038** the original statement text and an estimate of wall-clock time
2039** of how long that statement took to run.
drh19e2d372005-08-29 23:00:03 +00002040**
drh8b39db12009-02-18 18:37:58 +00002041** Requirements:
2042** [H12281] [H12282] [H12283] [H12284] [H12285] [H12287] [H12288] [H12289]
2043** [H12290]
drh18de4822003-01-16 16:28:53 +00002044*/
shanea79c3cc2008-08-11 17:27:01 +00002045SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
2046SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
drh6d2069d2007-08-14 01:58:53 +00002047 void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
drh18de4822003-01-16 16:28:53 +00002048
danielk1977348bb5d2003-10-18 09:37:26 +00002049/*
drh9cd29642008-07-23 00:52:55 +00002050** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
drh6ed48bf2007-06-14 20:57:18 +00002051**
drh33c1be32008-01-30 16:16:14 +00002052** This routine configures a callback function - the
drhfddfa2d2007-12-05 18:05:16 +00002053** progress callback - that is invoked periodically during long
2054** running calls to [sqlite3_exec()], [sqlite3_step()] and
mihailima3f64902008-06-21 13:35:56 +00002055** [sqlite3_get_table()]. An example use for this
drh6ed48bf2007-06-14 20:57:18 +00002056** interface is to keep a GUI updated during a large query.
danielk1977348bb5d2003-10-18 09:37:26 +00002057**
shane236ce972008-05-30 15:35:30 +00002058** If the progress callback returns non-zero, the operation is
drh33c1be32008-01-30 16:16:14 +00002059** interrupted. This feature can be used to implement a
drhc8075422008-09-10 13:09:23 +00002060** "Cancel" button on a GUI progress dialog box.
2061**
2062** The progress handler must not do anything that will modify
2063** the database connection that invoked the progress handler.
2064** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2065** database connections for the meaning of "modify" in this paragraph.
danielk1977348bb5d2003-10-18 09:37:26 +00002066**
drh8b39db12009-02-18 18:37:58 +00002067** Requirements:
2068** [H12911] [H12912] [H12913] [H12914] [H12915] [H12916] [H12917] [H12918]
drh33c1be32008-01-30 16:16:14 +00002069**
danielk1977348bb5d2003-10-18 09:37:26 +00002070*/
danielk1977f9d64d22004-06-19 08:18:07 +00002071void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
danielk1977348bb5d2003-10-18 09:37:26 +00002072
drhaa940ea2004-01-15 02:44:03 +00002073/*
drh9cd29642008-07-23 00:52:55 +00002074** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
drhaa940ea2004-01-15 02:44:03 +00002075**
mihailima3f64902008-06-21 13:35:56 +00002076** These routines open an SQLite database file whose name is given by the
2077** filename argument. The filename argument is interpreted as UTF-8 for
2078** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
2079** order for sqlite3_open16(). A [database connection] handle is usually
2080** returned in *ppDb, even if an error occurs. The only exception is that
2081** if SQLite is unable to allocate memory to hold the [sqlite3] object,
2082** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
2083** object. If the database is opened (and/or created) successfully, then
mihailimefc8e8a2008-06-21 16:47:09 +00002084** [SQLITE_OK] is returned. Otherwise an [error code] is returned. The
mihailima3f64902008-06-21 13:35:56 +00002085** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
drh4f26d6c2004-05-26 23:25:30 +00002086** an English language description of the error.
drh22fbcb82004-02-01 01:22:50 +00002087**
drh33c1be32008-01-30 16:16:14 +00002088** The default encoding for the database will be UTF-8 if
mihailima3f64902008-06-21 13:35:56 +00002089** sqlite3_open() or sqlite3_open_v2() is called and
2090** UTF-16 in the native byte order if sqlite3_open16() is used.
danielk197765904932004-05-26 06:18:37 +00002091**
drh33c1be32008-01-30 16:16:14 +00002092** Whether or not an error occurs when it is opened, resources
mihailima3f64902008-06-21 13:35:56 +00002093** associated with the [database connection] handle should be released by
2094** passing it to [sqlite3_close()] when it is no longer required.
drh6d2069d2007-08-14 01:58:53 +00002095**
mihailima3f64902008-06-21 13:35:56 +00002096** The sqlite3_open_v2() interface works like sqlite3_open()
shane26b34032008-05-23 17:21:09 +00002097** except that it accepts two additional parameters for additional control
danielk19779a6284c2008-07-10 17:52:49 +00002098** over the new database connection. The flags parameter can take one of
2099** the following three values, optionally combined with the
drhf1f12682009-09-09 14:17:52 +00002100** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
2101** and/or [SQLITE_OPEN_PRIVATECACHE] flags:
drh6d2069d2007-08-14 01:58:53 +00002102**
mihailima3f64902008-06-21 13:35:56 +00002103** <dl>
2104** <dt>[SQLITE_OPEN_READONLY]</dt>
2105** <dd>The database is opened in read-only mode. If the database does not
2106** already exist, an error is returned.</dd>
drh6d2069d2007-08-14 01:58:53 +00002107**
mihailima3f64902008-06-21 13:35:56 +00002108** <dt>[SQLITE_OPEN_READWRITE]</dt>
2109** <dd>The database is opened for reading and writing if possible, or reading
2110** only if the file is write protected by the operating system. In either
2111** case the database must already exist, otherwise an error is returned.</dd>
drh9da9d962007-08-28 15:47:44 +00002112**
mihailima3f64902008-06-21 13:35:56 +00002113** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
2114** <dd>The database is opened for reading and writing, and is creates it if
2115** it does not already exist. This is the behavior that is always used for
2116** sqlite3_open() and sqlite3_open16().</dd>
2117** </dl>
2118**
2119** If the 3rd parameter to sqlite3_open_v2() is not one of the
danielk19779a6284c2008-07-10 17:52:49 +00002120** combinations shown above or one of the combinations shown above combined
drhf1f12682009-09-09 14:17:52 +00002121** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
2122** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
drhafacce02008-09-02 21:35:03 +00002123** then the behavior is undefined.
danielk19779a6284c2008-07-10 17:52:49 +00002124**
drhafacce02008-09-02 21:35:03 +00002125** If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
2126** opens in the multi-thread [threading mode] as long as the single-thread
2127** mode has not been set at compile-time or start-time. If the
2128** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
2129** in the serialized [threading mode] unless single-thread was
2130** previously selected at compile-time or start-time.
drhf1f12682009-09-09 14:17:52 +00002131** The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
2132** eligible to use [shared cache mode], regardless of whether or not shared
2133** cache is enabled using [sqlite3_enable_shared_cache()]. The
2134** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
2135** participate in [shared cache mode] even if it is enabled.
drhd9b97cf2008-04-10 13:38:17 +00002136**
mihailima3f64902008-06-21 13:35:56 +00002137** If the filename is ":memory:", then a private, temporary in-memory database
2138** is created for the connection. This in-memory database will vanish when
2139** the database connection is closed. Future versions of SQLite might
2140** make use of additional special filenames that begin with the ":" character.
2141** It is recommended that when a database filename actually does begin with
2142** a ":" character you should prefix the filename with a pathname such as
2143** "./" to avoid ambiguity.
drh6d2069d2007-08-14 01:58:53 +00002144**
mihailima3f64902008-06-21 13:35:56 +00002145** If the filename is an empty string, then a private, temporary
drh33c1be32008-01-30 16:16:14 +00002146** on-disk database will be created. This private database will be
drh3f3b6352007-09-03 20:32:45 +00002147** automatically deleted as soon as the database connection is closed.
2148**
drh33c1be32008-01-30 16:16:14 +00002149** The fourth parameter to sqlite3_open_v2() is the name of the
mihailima3f64902008-06-21 13:35:56 +00002150** [sqlite3_vfs] object that defines the operating system interface that
2151** the new database connection should use. If the fourth parameter is
2152** a NULL pointer then the default [sqlite3_vfs] object is used.
drh6ed48bf2007-06-14 20:57:18 +00002153**
shane26b34032008-05-23 17:21:09 +00002154** <b>Note to Windows users:</b> The encoding used for the filename argument
mihailima3f64902008-06-21 13:35:56 +00002155** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
drh9da9d962007-08-28 15:47:44 +00002156** codepage is currently defined. Filenames containing international
2157** characters must be converted to UTF-8 prior to passing them into
mihailima3f64902008-06-21 13:35:56 +00002158** sqlite3_open() or sqlite3_open_v2().
drh33c1be32008-01-30 16:16:14 +00002159**
drh8b39db12009-02-18 18:37:58 +00002160** Requirements:
2161** [H12701] [H12702] [H12703] [H12704] [H12706] [H12707] [H12709] [H12711]
2162** [H12712] [H12713] [H12714] [H12717] [H12719] [H12721] [H12723]
danielk197765904932004-05-26 06:18:37 +00002163*/
2164int sqlite3_open(
2165 const char *filename, /* Database filename (UTF-8) */
danielk19774f057f92004-06-08 00:02:33 +00002166 sqlite3 **ppDb /* OUT: SQLite db handle */
danielk197765904932004-05-26 06:18:37 +00002167);
danielk197765904932004-05-26 06:18:37 +00002168int sqlite3_open16(
2169 const void *filename, /* Database filename (UTF-16) */
danielk19774f057f92004-06-08 00:02:33 +00002170 sqlite3 **ppDb /* OUT: SQLite db handle */
danielk197765904932004-05-26 06:18:37 +00002171);
drh6d2069d2007-08-14 01:58:53 +00002172int sqlite3_open_v2(
drh428e2822007-08-30 16:23:19 +00002173 const char *filename, /* Database filename (UTF-8) */
drh6d2069d2007-08-14 01:58:53 +00002174 sqlite3 **ppDb, /* OUT: SQLite db handle */
2175 int flags, /* Flags */
drhd84f9462007-08-15 11:28:56 +00002176 const char *zVfs /* Name of VFS module to use */
drh6d2069d2007-08-14 01:58:53 +00002177);
danielk1977295ba552004-05-19 10:34:51 +00002178
danielk197765904932004-05-26 06:18:37 +00002179/*
drh9cd29642008-07-23 00:52:55 +00002180** CAPI3REF: Error Codes And Messages {H12800} <S60200>
drh6ed48bf2007-06-14 20:57:18 +00002181**
mihailimefc8e8a2008-06-21 16:47:09 +00002182** The sqlite3_errcode() interface returns the numeric [result code] or
2183** [extended result code] for the most recent failed sqlite3_* API call
2184** associated with a [database connection]. If a prior API call failed
2185** but the most recent API call succeeded, the return value from
drh99dfe5e2008-10-30 15:03:15 +00002186** sqlite3_errcode() is undefined. The sqlite3_extended_errcode()
2187** interface is the same except that it always returns the
2188** [extended result code] even when extended result codes are
2189** disabled.
drh6ed48bf2007-06-14 20:57:18 +00002190**
drh33c1be32008-01-30 16:16:14 +00002191** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
mihailimebe796c2008-06-21 20:11:17 +00002192** text that describes the error, as either UTF-8 or UTF-16 respectively.
drh33c1be32008-01-30 16:16:14 +00002193** Memory to hold the error message string is managed internally.
mihailimefc8e8a2008-06-21 16:47:09 +00002194** The application does not need to worry about freeing the result.
mlcreech27358862008-03-01 23:34:46 +00002195** However, the error string might be overwritten or deallocated by
drh33c1be32008-01-30 16:16:14 +00002196** subsequent calls to other SQLite interface functions.
danielk197765904932004-05-26 06:18:37 +00002197**
drh2838b472008-11-04 14:48:22 +00002198** When the serialized [threading mode] is in use, it might be the
2199** case that a second error occurs on a separate thread in between
2200** the time of the first error and the call to these interfaces.
2201** When that happens, the second error will be reported since these
2202** interfaces always report the most recent result. To avoid
2203** this, each thread can obtain exclusive use of the [database connection] D
2204** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
2205** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
2206** all calls to the interfaces listed here are completed.
2207**
drhd55d57e2008-07-07 17:53:07 +00002208** If an interface fails with SQLITE_MISUSE, that means the interface
2209** was invoked incorrectly by the application. In that case, the
2210** error code and message may or may not be set.
2211**
drh8b39db12009-02-18 18:37:58 +00002212** Requirements:
2213** [H12801] [H12802] [H12803] [H12807] [H12808] [H12809]
danielk197765904932004-05-26 06:18:37 +00002214*/
2215int sqlite3_errcode(sqlite3 *db);
drh99dfe5e2008-10-30 15:03:15 +00002216int sqlite3_extended_errcode(sqlite3 *db);
danielk197765904932004-05-26 06:18:37 +00002217const char *sqlite3_errmsg(sqlite3*);
danielk197765904932004-05-26 06:18:37 +00002218const void *sqlite3_errmsg16(sqlite3*);
2219
2220/*
drh9cd29642008-07-23 00:52:55 +00002221** CAPI3REF: SQL Statement Object {H13000} <H13010>
drh33c1be32008-01-30 16:16:14 +00002222** KEYWORDS: {prepared statement} {prepared statements}
drh6ed48bf2007-06-14 20:57:18 +00002223**
mihailimefc8e8a2008-06-21 16:47:09 +00002224** An instance of this object represents a single SQL statement.
2225** This object is variously known as a "prepared statement" or a
drh6ed48bf2007-06-14 20:57:18 +00002226** "compiled SQL statement" or simply as a "statement".
mihailimefc8e8a2008-06-21 16:47:09 +00002227**
drh6ed48bf2007-06-14 20:57:18 +00002228** The life of a statement object goes something like this:
2229**
2230** <ol>
2231** <li> Create the object using [sqlite3_prepare_v2()] or a related
2232** function.
mihailimefc8e8a2008-06-21 16:47:09 +00002233** <li> Bind values to [host parameters] using the sqlite3_bind_*()
2234** interfaces.
drh6ed48bf2007-06-14 20:57:18 +00002235** <li> Run the SQL by calling [sqlite3_step()] one or more times.
2236** <li> Reset the statement using [sqlite3_reset()] then go back
2237** to step 2. Do this zero or more times.
2238** <li> Destroy the object using [sqlite3_finalize()].
2239** </ol>
2240**
2241** Refer to documentation on individual methods above for additional
2242** information.
danielk197765904932004-05-26 06:18:37 +00002243*/
danielk1977fc57d7b2004-05-26 02:04:57 +00002244typedef struct sqlite3_stmt sqlite3_stmt;
2245
danielk1977e3209e42004-05-20 01:40:18 +00002246/*
drh9cd29642008-07-23 00:52:55 +00002247** CAPI3REF: Run-time Limits {H12760} <S20600>
drhcaa639f2008-03-20 00:32:20 +00002248**
2249** This interface allows the size of various constructs to be limited
2250** on a connection by connection basis. The first parameter is the
2251** [database connection] whose limit is to be set or queried. The
2252** second parameter is one of the [limit categories] that define a
2253** class of constructs to be size limited. The third parameter is the
2254** new limit for that construct. The function returns the old limit.
2255**
2256** If the new limit is a negative number, the limit is unchanged.
drhae1a8802009-02-11 15:04:40 +00002257** For the limit category of SQLITE_LIMIT_XYZ there is a
2258** [limits | hard upper bound]
2259** set by a compile-time C preprocessor macro named
2260** [limits | SQLITE_MAX_XYZ].
drhf47ce562008-03-20 18:00:49 +00002261** (The "_LIMIT_" in the name is changed to "_MAX_".)
2262** Attempts to increase a limit above its hard upper bound are
2263** silently truncated to the hard upper limit.
drhcaa639f2008-03-20 00:32:20 +00002264**
drhbb4957f2008-03-20 14:03:29 +00002265** Run time limits are intended for use in applications that manage
2266** both their own internal database and also databases that are controlled
2267** by untrusted external sources. An example application might be a
drh46f33ef2009-02-11 15:23:35 +00002268** web browser that has its own databases for storing history and
shane26b34032008-05-23 17:21:09 +00002269** separate databases controlled by JavaScript applications downloaded
shane236ce972008-05-30 15:35:30 +00002270** off the Internet. The internal databases can be given the
drhbb4957f2008-03-20 14:03:29 +00002271** large, default limits. Databases managed by external sources can
2272** be given much smaller limits designed to prevent a denial of service
mihailimefc8e8a2008-06-21 16:47:09 +00002273** attack. Developers might also want to use the [sqlite3_set_authorizer()]
drhf47ce562008-03-20 18:00:49 +00002274** interface to further control untrusted SQL. The size of the database
2275** created by an untrusted script can be contained using the
2276** [max_page_count] [PRAGMA].
drhbb4957f2008-03-20 14:03:29 +00002277**
drha911abe2008-07-16 13:29:51 +00002278** New run-time limit categories may be added in future releases.
drhcaa639f2008-03-20 00:32:20 +00002279**
drh8b39db12009-02-18 18:37:58 +00002280** Requirements:
2281** [H12762] [H12766] [H12769]
drhcaa639f2008-03-20 00:32:20 +00002282*/
2283int sqlite3_limit(sqlite3*, int id, int newVal);
2284
2285/*
drh9cd29642008-07-23 00:52:55 +00002286** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
drhcaa639f2008-03-20 00:32:20 +00002287** KEYWORDS: {limit category} {limit categories}
mihailimefc8e8a2008-06-21 16:47:09 +00002288**
drh46f33ef2009-02-11 15:23:35 +00002289** These constants define various performance limits
2290** that can be lowered at run-time using [sqlite3_limit()].
2291** The synopsis of the meanings of the various limits is shown below.
2292** Additional information is available at [limits | Limits in SQLite].
drhbb4957f2008-03-20 14:03:29 +00002293**
2294** <dl>
2295** <dt>SQLITE_LIMIT_LENGTH</dt>
mihailimefc8e8a2008-06-21 16:47:09 +00002296** <dd>The maximum size of any string or BLOB or table row.<dd>
drhbb4957f2008-03-20 14:03:29 +00002297**
2298** <dt>SQLITE_LIMIT_SQL_LENGTH</dt>
2299** <dd>The maximum length of an SQL statement.</dd>
2300**
2301** <dt>SQLITE_LIMIT_COLUMN</dt>
2302** <dd>The maximum number of columns in a table definition or in the
drh46f33ef2009-02-11 15:23:35 +00002303** result set of a [SELECT] or the maximum number of columns in an index
drhbb4957f2008-03-20 14:03:29 +00002304** or in an ORDER BY or GROUP BY clause.</dd>
2305**
2306** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
2307** <dd>The maximum depth of the parse tree on any expression.</dd>
2308**
2309** <dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
2310** <dd>The maximum number of terms in a compound SELECT statement.</dd>
2311**
2312** <dt>SQLITE_LIMIT_VDBE_OP</dt>
2313** <dd>The maximum number of instructions in a virtual machine program
2314** used to implement an SQL statement.</dd>
2315**
2316** <dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
2317** <dd>The maximum number of arguments on a function.</dd>
2318**
2319** <dt>SQLITE_LIMIT_ATTACHED</dt>
drh46f33ef2009-02-11 15:23:35 +00002320** <dd>The maximum number of [ATTACH | attached databases].</dd>
drhbb4957f2008-03-20 14:03:29 +00002321**
drhbb4957f2008-03-20 14:03:29 +00002322** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
drh46f33ef2009-02-11 15:23:35 +00002323** <dd>The maximum length of the pattern argument to the [LIKE] or
2324** [GLOB] operators.</dd>
drhbb4957f2008-03-20 14:03:29 +00002325**
2326** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
2327** <dd>The maximum number of variables in an SQL statement that can
2328** be bound.</dd>
drh417168a2009-09-07 18:14:02 +00002329**
2330** <dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
2331** <dd>The maximum depth of recursion for triggers.</dd>
drhbb4957f2008-03-20 14:03:29 +00002332** </dl>
drhcaa639f2008-03-20 00:32:20 +00002333*/
2334#define SQLITE_LIMIT_LENGTH 0
2335#define SQLITE_LIMIT_SQL_LENGTH 1
2336#define SQLITE_LIMIT_COLUMN 2
2337#define SQLITE_LIMIT_EXPR_DEPTH 3
2338#define SQLITE_LIMIT_COMPOUND_SELECT 4
2339#define SQLITE_LIMIT_VDBE_OP 5
2340#define SQLITE_LIMIT_FUNCTION_ARG 6
2341#define SQLITE_LIMIT_ATTACHED 7
drhb1a6c3c2008-03-20 16:30:17 +00002342#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
2343#define SQLITE_LIMIT_VARIABLE_NUMBER 9
drh417168a2009-09-07 18:14:02 +00002344#define SQLITE_LIMIT_TRIGGER_DEPTH 10
drhcaa639f2008-03-20 00:32:20 +00002345
2346/*
drh9cd29642008-07-23 00:52:55 +00002347** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
mihailimefc8e8a2008-06-21 16:47:09 +00002348** KEYWORDS: {SQL statement compiler}
danielk197765904932004-05-26 06:18:37 +00002349**
drh6ed48bf2007-06-14 20:57:18 +00002350** To execute an SQL query, it must first be compiled into a byte-code
mihailimefc8e8a2008-06-21 16:47:09 +00002351** program using one of these routines.
drh6ed48bf2007-06-14 20:57:18 +00002352**
mihailimefc8e8a2008-06-21 16:47:09 +00002353** The first argument, "db", is a [database connection] obtained from a
drh860e0772009-04-02 18:32:26 +00002354** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
2355** [sqlite3_open16()]. The database connection must not have been closed.
mihailimefc8e8a2008-06-21 16:47:09 +00002356**
2357** The second argument, "zSql", is the statement to be compiled, encoded
drh6ed48bf2007-06-14 20:57:18 +00002358** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
mihailimefc8e8a2008-06-21 16:47:09 +00002359** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
mihailim04bcc002008-06-22 10:21:27 +00002360** use UTF-16.
drh21f06722007-07-19 12:41:39 +00002361**
mihailimefc8e8a2008-06-21 16:47:09 +00002362** If the nByte argument is less than zero, then zSql is read up to the
2363** first zero terminator. If nByte is non-negative, then it is the maximum
2364** number of bytes read from zSql. When nByte is non-negative, the
2365** zSql string ends at either the first '\000' or '\u0000' character or
drhb08c2a72008-04-16 00:28:13 +00002366** the nByte-th byte, whichever comes first. If the caller knows
danielk19773a2c8c82008-04-03 14:36:25 +00002367** that the supplied string is nul-terminated, then there is a small
mihailimefc8e8a2008-06-21 16:47:09 +00002368** performance advantage to be gained by passing an nByte parameter that
2369** is equal to the number of bytes in the input string <i>including</i>
mihailim04bcc002008-06-22 10:21:27 +00002370** the nul-terminator bytes.
danielk197765904932004-05-26 06:18:37 +00002371**
drh860e0772009-04-02 18:32:26 +00002372** If pzTail is not NULL then *pzTail is made to point to the first byte
2373** past the end of the first SQL statement in zSql. These routines only
2374** compile the first statement in zSql, so *pzTail is left pointing to
2375** what remains uncompiled.
danielk197765904932004-05-26 06:18:37 +00002376**
drh33c1be32008-01-30 16:16:14 +00002377** *ppStmt is left pointing to a compiled [prepared statement] that can be
mihailimefc8e8a2008-06-21 16:47:09 +00002378** executed using [sqlite3_step()]. If there is an error, *ppStmt is set
2379** to NULL. If the input text contains no SQL (if the input is an empty
2380** string or a comment) then *ppStmt is set to NULL.
drh860e0772009-04-02 18:32:26 +00002381** The calling procedure is responsible for deleting the compiled
mihailimefc8e8a2008-06-21 16:47:09 +00002382** SQL statement using [sqlite3_finalize()] after it has finished with it.
drh860e0772009-04-02 18:32:26 +00002383** ppStmt may not be NULL.
danielk197765904932004-05-26 06:18:37 +00002384**
mihailimefc8e8a2008-06-21 16:47:09 +00002385** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
drh6ed48bf2007-06-14 20:57:18 +00002386**
2387** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
2388** recommended for all new programs. The two older interfaces are retained
2389** for backwards compatibility, but their use is discouraged.
drh33c1be32008-01-30 16:16:14 +00002390** In the "v2" interfaces, the prepared statement
mihailimefc8e8a2008-06-21 16:47:09 +00002391** that is returned (the [sqlite3_stmt] object) contains a copy of the
mihailim04bcc002008-06-22 10:21:27 +00002392** original SQL text. This causes the [sqlite3_step()] interface to
drh4b5af772009-10-20 14:08:41 +00002393** behave a differently in three ways:
drh6ed48bf2007-06-14 20:57:18 +00002394**
2395** <ol>
drh33c1be32008-01-30 16:16:14 +00002396** <li>
drh6ed48bf2007-06-14 20:57:18 +00002397** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
2398** always used to do, [sqlite3_step()] will automatically recompile the SQL
drh33c1be32008-01-30 16:16:14 +00002399** statement and try to run it again. If the schema has changed in
drhfddfa2d2007-12-05 18:05:16 +00002400** a way that makes the statement no longer valid, [sqlite3_step()] will still
mihailimefc8e8a2008-06-21 16:47:09 +00002401** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
2402** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
drh33c1be32008-01-30 16:16:14 +00002403** error go away. Note: use [sqlite3_errmsg()] to find the text
mihailim04bcc002008-06-22 10:21:27 +00002404** of the parsing error that results in an [SQLITE_SCHEMA] return.
drh6ed48bf2007-06-14 20:57:18 +00002405** </li>
2406**
2407** <li>
mihailimefc8e8a2008-06-21 16:47:09 +00002408** When an error occurs, [sqlite3_step()] will return one of the detailed
2409** [error codes] or [extended error codes]. The legacy behavior was that
2410** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
2411** and you would have to make a second call to [sqlite3_reset()] in order
2412** to find the underlying cause of the problem. With the "v2" prepare
2413** interfaces, the underlying reason for the error is returned immediately.
drh6ed48bf2007-06-14 20:57:18 +00002414** </li>
drh4b5af772009-10-20 14:08:41 +00002415**
2416** <li>
2417** ^If the value of a [parameter | host parameter] in the WHERE clause might
2418** change the query plan for a statement, then the statement may be
2419** automatically recompiled (as if there had been a schema change) on the first
2420** [sqlite3_step()] call following any change to the
2421** [sqlite3_bind_text | bindings] of the [parameter].
2422** </li>
drh6ed48bf2007-06-14 20:57:18 +00002423** </ol>
drh33c1be32008-01-30 16:16:14 +00002424**
drh8b39db12009-02-18 18:37:58 +00002425** Requirements:
2426** [H13011] [H13012] [H13013] [H13014] [H13015] [H13016] [H13019] [H13021]
drh33c1be32008-01-30 16:16:14 +00002427**
danielk197765904932004-05-26 06:18:37 +00002428*/
2429int sqlite3_prepare(
2430 sqlite3 *db, /* Database handle */
2431 const char *zSql, /* SQL statement, UTF-8 encoded */
drh21f06722007-07-19 12:41:39 +00002432 int nByte, /* Maximum length of zSql in bytes. */
danielk197765904932004-05-26 06:18:37 +00002433 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2434 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2435);
drh6ed48bf2007-06-14 20:57:18 +00002436int sqlite3_prepare_v2(
2437 sqlite3 *db, /* Database handle */
2438 const char *zSql, /* SQL statement, UTF-8 encoded */
drh21f06722007-07-19 12:41:39 +00002439 int nByte, /* Maximum length of zSql in bytes. */
drh6ed48bf2007-06-14 20:57:18 +00002440 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2441 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2442);
danielk197765904932004-05-26 06:18:37 +00002443int sqlite3_prepare16(
2444 sqlite3 *db, /* Database handle */
2445 const void *zSql, /* SQL statement, UTF-16 encoded */
drh21f06722007-07-19 12:41:39 +00002446 int nByte, /* Maximum length of zSql in bytes. */
danielk197765904932004-05-26 06:18:37 +00002447 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2448 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2449);
drhb900aaf2006-11-09 00:24:53 +00002450int sqlite3_prepare16_v2(
2451 sqlite3 *db, /* Database handle */
2452 const void *zSql, /* SQL statement, UTF-16 encoded */
drh21f06722007-07-19 12:41:39 +00002453 int nByte, /* Maximum length of zSql in bytes. */
drhb900aaf2006-11-09 00:24:53 +00002454 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2455 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2456);
2457
2458/*
drh25ef8f12008-10-02 14:33:56 +00002459** CAPI3REF: Retrieving Statement SQL {H13100} <H13000>
danielk1977d0e2a852007-11-14 06:48:48 +00002460**
mihailimefc8e8a2008-06-21 16:47:09 +00002461** This interface can be used to retrieve a saved copy of the original
2462** SQL text used to create a [prepared statement] if that statement was
2463** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
danielk1977d0e2a852007-11-14 06:48:48 +00002464**
drh8b39db12009-02-18 18:37:58 +00002465** Requirements:
2466** [H13101] [H13102] [H13103]
danielk1977d0e2a852007-11-14 06:48:48 +00002467*/
2468const char *sqlite3_sql(sqlite3_stmt *pStmt);
2469
2470/*
drhb25f9d82008-07-23 15:40:06 +00002471** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
drhaa28e142008-03-18 13:47:20 +00002472** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
drh6ed48bf2007-06-14 20:57:18 +00002473**
drh33c1be32008-01-30 16:16:14 +00002474** SQLite uses the sqlite3_value object to represent all values
mihailimefc8e8a2008-06-21 16:47:09 +00002475** that can be stored in a database table. SQLite uses dynamic typing
2476** for the values it stores. Values stored in sqlite3_value objects
2477** can be integers, floating point values, strings, BLOBs, or NULL.
drhaa28e142008-03-18 13:47:20 +00002478**
2479** An sqlite3_value object may be either "protected" or "unprotected".
2480** Some interfaces require a protected sqlite3_value. Other interfaces
2481** will accept either a protected or an unprotected sqlite3_value.
mihailimefc8e8a2008-06-21 16:47:09 +00002482** Every interface that accepts sqlite3_value arguments specifies
drhaa28e142008-03-18 13:47:20 +00002483** whether or not it requires a protected sqlite3_value.
2484**
2485** The terms "protected" and "unprotected" refer to whether or not
2486** a mutex is held. A internal mutex is held for a protected
2487** sqlite3_value object but no mutex is held for an unprotected
2488** sqlite3_value object. If SQLite is compiled to be single-threaded
drh4766b292008-06-26 02:53:02 +00002489** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
drh4ead1482008-06-26 18:16:05 +00002490** or if SQLite is run in one of reduced mutex modes
2491** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
mihailimefc8e8a2008-06-21 16:47:09 +00002492** then there is no distinction between protected and unprotected
2493** sqlite3_value objects and they can be used interchangeably. However,
2494** for maximum code portability it is recommended that applications
2495** still make the distinction between between protected and unprotected
drh4ead1482008-06-26 18:16:05 +00002496** sqlite3_value objects even when not strictly required.
drhaa28e142008-03-18 13:47:20 +00002497**
2498** The sqlite3_value objects that are passed as parameters into the
mihailimefc8e8a2008-06-21 16:47:09 +00002499** implementation of [application-defined SQL functions] are protected.
drhaa28e142008-03-18 13:47:20 +00002500** The sqlite3_value object returned by
2501** [sqlite3_column_value()] is unprotected.
2502** Unprotected sqlite3_value objects may only be used with
mihailimefc8e8a2008-06-21 16:47:09 +00002503** [sqlite3_result_value()] and [sqlite3_bind_value()].
drhce5a5a02008-06-10 17:41:44 +00002504** The [sqlite3_value_blob | sqlite3_value_type()] family of
2505** interfaces require protected sqlite3_value objects.
drhf4479502004-05-27 03:12:53 +00002506*/
drhf4479502004-05-27 03:12:53 +00002507typedef struct Mem sqlite3_value;
2508
2509/*
drhb25f9d82008-07-23 15:40:06 +00002510** CAPI3REF: SQL Function Context Object {H16001} <S20200>
drh4f26d6c2004-05-26 23:25:30 +00002511**
drh6ed48bf2007-06-14 20:57:18 +00002512** The context in which an SQL function executes is stored in an
mihailimefc8e8a2008-06-21 16:47:09 +00002513** sqlite3_context object. A pointer to an sqlite3_context object
2514** is always first parameter to [application-defined SQL functions].
2515** The application-defined SQL function implementation will pass this
2516** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
2517** [sqlite3_aggregate_context()], [sqlite3_user_data()],
2518** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
2519** and/or [sqlite3_set_auxdata()].
drh6ed48bf2007-06-14 20:57:18 +00002520*/
2521typedef struct sqlite3_context sqlite3_context;
2522
2523/*
drhb25f9d82008-07-23 15:40:06 +00002524** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300>
mihailimefc8e8a2008-06-21 16:47:09 +00002525** KEYWORDS: {host parameter} {host parameters} {host parameter name}
mihailimebe796c2008-06-21 20:11:17 +00002526** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
drh6ed48bf2007-06-14 20:57:18 +00002527**
mihailimefc8e8a2008-06-21 16:47:09 +00002528** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
drh333ceb92009-08-25 14:59:37 +00002529** literals may be replaced by a [parameter] that matches one of following
2530** templates:
drh6ed48bf2007-06-14 20:57:18 +00002531**
2532** <ul>
2533** <li> ?
2534** <li> ?NNN
drh33c1be32008-01-30 16:16:14 +00002535** <li> :VVV
2536** <li> @VVV
drh6ed48bf2007-06-14 20:57:18 +00002537** <li> $VVV
2538** </ul>
2539**
drh333ceb92009-08-25 14:59:37 +00002540** In the templates above, NNN represents an integer literal,
2541** and VVV represents an alphanumeric identifer. The values of these
mihailimefc8e8a2008-06-21 16:47:09 +00002542** parameters (also called "host parameter names" or "SQL parameters")
drh6ed48bf2007-06-14 20:57:18 +00002543** can be set using the sqlite3_bind_*() routines defined here.
2544**
mihailimefc8e8a2008-06-21 16:47:09 +00002545** The first argument to the sqlite3_bind_*() routines is always
2546** a pointer to the [sqlite3_stmt] object returned from
2547** [sqlite3_prepare_v2()] or its variants.
2548**
2549** The second argument is the index of the SQL parameter to be set.
2550** The leftmost SQL parameter has an index of 1. When the same named
2551** SQL parameter is used more than once, second and subsequent
2552** occurrences have the same index as the first occurrence.
drh33c1be32008-01-30 16:16:14 +00002553** The index for named parameters can be looked up using the
danielk1977c001fc32008-06-24 09:52:39 +00002554** [sqlite3_bind_parameter_index()] API if desired. The index
drhf5befa02007-12-06 02:42:07 +00002555** for "?NNN" parameters is the value of NNN.
drh4ead1482008-06-26 18:16:05 +00002556** The NNN value must be between 1 and the [sqlite3_limit()]
2557** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
drh6ed48bf2007-06-14 20:57:18 +00002558**
drh33c1be32008-01-30 16:16:14 +00002559** The third argument is the value to bind to the parameter.
drh6ed48bf2007-06-14 20:57:18 +00002560**
mihailimefc8e8a2008-06-21 16:47:09 +00002561** In those routines that have a fourth argument, its value is the
2562** number of bytes in the parameter. To be clear: the value is the
2563** number of <u>bytes</u> in the value, not the number of characters.
drh6ed48bf2007-06-14 20:57:18 +00002564** If the fourth parameter is negative, the length of the string is
shane26b34032008-05-23 17:21:09 +00002565** the number of bytes up to the first zero terminator.
drh4f26d6c2004-05-26 23:25:30 +00002566**
drh930cc582007-03-28 13:07:40 +00002567** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
drh900dfba2004-07-21 15:21:36 +00002568** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
drh33c1be32008-01-30 16:16:14 +00002569** string after SQLite has finished with it. If the fifth argument is
2570** the special value [SQLITE_STATIC], then SQLite assumes that the
drhfddfa2d2007-12-05 18:05:16 +00002571** information is in static, unmanaged space and does not need to be freed.
drh33c1be32008-01-30 16:16:14 +00002572** If the fifth argument has the value [SQLITE_TRANSIENT], then
drhfddfa2d2007-12-05 18:05:16 +00002573** SQLite makes its own private copy of the data immediately, before
drh33c1be32008-01-30 16:16:14 +00002574** the sqlite3_bind_*() routine returns.
drh4f26d6c2004-05-26 23:25:30 +00002575**
drh33c1be32008-01-30 16:16:14 +00002576** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
mihailimefc8e8a2008-06-21 16:47:09 +00002577** is filled with zeroes. A zeroblob uses a fixed amount of memory
2578** (just an integer to hold its size) while it is being processed.
shane26b34032008-05-23 17:21:09 +00002579** Zeroblobs are intended to serve as placeholders for BLOBs whose
mihailimefc8e8a2008-06-21 16:47:09 +00002580** content is later written using
2581** [sqlite3_blob_open | incremental BLOB I/O] routines.
2582** A negative value for the zeroblob results in a zero-length BLOB.
drh6ed48bf2007-06-14 20:57:18 +00002583**
drh33c1be32008-01-30 16:16:14 +00002584** The sqlite3_bind_*() routines must be called after
drh6ed48bf2007-06-14 20:57:18 +00002585** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
drh33c1be32008-01-30 16:16:14 +00002586** before [sqlite3_step()].
drh6ed48bf2007-06-14 20:57:18 +00002587** Bindings are not cleared by the [sqlite3_reset()] routine.
drh33c1be32008-01-30 16:16:14 +00002588** Unbound parameters are interpreted as NULL.
drh6ed48bf2007-06-14 20:57:18 +00002589**
drh33c1be32008-01-30 16:16:14 +00002590** These routines return [SQLITE_OK] on success or an error code if
2591** anything goes wrong. [SQLITE_RANGE] is returned if the parameter
shane26b34032008-05-23 17:21:09 +00002592** index is out of range. [SQLITE_NOMEM] is returned if malloc() fails.
drh33c1be32008-01-30 16:16:14 +00002593** [SQLITE_MISUSE] might be returned if these routines are called on a
drhfddfa2d2007-12-05 18:05:16 +00002594** virtual machine that is the wrong state or which has already been finalized.
drh33c1be32008-01-30 16:16:14 +00002595** Detection of misuse is unreliable. Applications should not depend
2596** on SQLITE_MISUSE returns. SQLITE_MISUSE is intended to indicate a
2597** a logic error in the application. Future versions of SQLite might
2598** panic rather than return SQLITE_MISUSE.
2599**
2600** See also: [sqlite3_bind_parameter_count()],
mihailimefc8e8a2008-06-21 16:47:09 +00002601** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
drh33c1be32008-01-30 16:16:14 +00002602**
drh8b39db12009-02-18 18:37:58 +00002603** Requirements:
2604** [H13506] [H13509] [H13512] [H13515] [H13518] [H13521] [H13524] [H13527]
2605** [H13530] [H13533] [H13536] [H13539] [H13542] [H13545] [H13548] [H13551]
drh33c1be32008-01-30 16:16:14 +00002606**
drh4f26d6c2004-05-26 23:25:30 +00002607*/
danielk1977d8123362004-06-12 09:25:12 +00002608int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
drhf4479502004-05-27 03:12:53 +00002609int sqlite3_bind_double(sqlite3_stmt*, int, double);
2610int sqlite3_bind_int(sqlite3_stmt*, int, int);
drh6d2069d2007-08-14 01:58:53 +00002611int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
drhf4479502004-05-27 03:12:53 +00002612int sqlite3_bind_null(sqlite3_stmt*, int);
danielk1977d8123362004-06-12 09:25:12 +00002613int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
2614int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
drhf4479502004-05-27 03:12:53 +00002615int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
drhb026e052007-05-02 01:34:31 +00002616int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
drh4f26d6c2004-05-26 23:25:30 +00002617
2618/*
drhb25f9d82008-07-23 15:40:06 +00002619** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
drh6ed48bf2007-06-14 20:57:18 +00002620**
mihailimefc8e8a2008-06-21 16:47:09 +00002621** This routine can be used to find the number of [SQL parameters]
2622** in a [prepared statement]. SQL parameters are tokens of the
drh33c1be32008-01-30 16:16:14 +00002623** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
shane26b34032008-05-23 17:21:09 +00002624** placeholders for values that are [sqlite3_bind_blob | bound]
drh33c1be32008-01-30 16:16:14 +00002625** to the parameters at a later time.
drh605264d2007-08-21 15:13:19 +00002626**
mihailim1c492652008-06-21 18:02:16 +00002627** This routine actually returns the index of the largest (rightmost)
mihailimefc8e8a2008-06-21 16:47:09 +00002628** parameter. For all forms except ?NNN, this will correspond to the
2629** number of unique parameters. If parameters of the ?NNN are used,
2630** there may be gaps in the list.
drh33c1be32008-01-30 16:16:14 +00002631**
2632** See also: [sqlite3_bind_blob|sqlite3_bind()],
2633** [sqlite3_bind_parameter_name()], and
2634** [sqlite3_bind_parameter_index()].
2635**
drh8b39db12009-02-18 18:37:58 +00002636** Requirements:
2637** [H13601]
drh75f6a032004-07-15 14:15:00 +00002638*/
2639int sqlite3_bind_parameter_count(sqlite3_stmt*);
2640
2641/*
drhb25f9d82008-07-23 15:40:06 +00002642** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
drh6ed48bf2007-06-14 20:57:18 +00002643**
drh33c1be32008-01-30 16:16:14 +00002644** This routine returns a pointer to the name of the n-th
mihailimefc8e8a2008-06-21 16:47:09 +00002645** [SQL parameter] in a [prepared statement].
drhe1b3e802008-04-27 22:29:01 +00002646** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
2647** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
2648** respectively.
2649** In other words, the initial ":" or "$" or "@" or "?"
drh33c1be32008-01-30 16:16:14 +00002650** is included as part of the name.
mihailimefc8e8a2008-06-21 16:47:09 +00002651** Parameters of the form "?" without a following integer have no name
2652** and are also referred to as "anonymous parameters".
drh6ed48bf2007-06-14 20:57:18 +00002653**
drh33c1be32008-01-30 16:16:14 +00002654** The first host parameter has an index of 1, not 0.
drh6ed48bf2007-06-14 20:57:18 +00002655**
drh33c1be32008-01-30 16:16:14 +00002656** If the value n is out of range or if the n-th parameter is
2657** nameless, then NULL is returned. The returned string is
mihailimefc8e8a2008-06-21 16:47:09 +00002658** always in UTF-8 encoding even if the named parameter was
drhfddfa2d2007-12-05 18:05:16 +00002659** originally specified as UTF-16 in [sqlite3_prepare16()] or
2660** [sqlite3_prepare16_v2()].
drh33c1be32008-01-30 16:16:14 +00002661**
2662** See also: [sqlite3_bind_blob|sqlite3_bind()],
2663** [sqlite3_bind_parameter_count()], and
2664** [sqlite3_bind_parameter_index()].
2665**
drh8b39db12009-02-18 18:37:58 +00002666** Requirements:
2667** [H13621]
drh895d7472004-08-20 16:02:39 +00002668*/
2669const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
2670
2671/*
drhb25f9d82008-07-23 15:40:06 +00002672** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
drh6ed48bf2007-06-14 20:57:18 +00002673**
drh33c1be32008-01-30 16:16:14 +00002674** Return the index of an SQL parameter given its name. The
2675** index value returned is suitable for use as the second
2676** parameter to [sqlite3_bind_blob|sqlite3_bind()]. A zero
2677** is returned if no matching parameter is found. The parameter
2678** name must be given in UTF-8 even if the original statement
2679** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
2680**
2681** See also: [sqlite3_bind_blob|sqlite3_bind()],
2682** [sqlite3_bind_parameter_count()], and
2683** [sqlite3_bind_parameter_index()].
2684**
drh8b39db12009-02-18 18:37:58 +00002685** Requirements:
2686** [H13641]
drhfa6bc002004-09-07 16:19:52 +00002687*/
2688int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
2689
2690/*
drhb25f9d82008-07-23 15:40:06 +00002691** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
drh6ed48bf2007-06-14 20:57:18 +00002692**
mihailimefc8e8a2008-06-21 16:47:09 +00002693** Contrary to the intuition of many, [sqlite3_reset()] does not reset
2694** the [sqlite3_bind_blob | bindings] on a [prepared statement].
2695** Use this routine to reset all host parameters to NULL.
drh33c1be32008-01-30 16:16:14 +00002696**
drh8b39db12009-02-18 18:37:58 +00002697** Requirements:
2698** [H13661]
danielk1977600dd0b2005-01-20 01:14:23 +00002699*/
2700int sqlite3_clear_bindings(sqlite3_stmt*);
2701
2702/*
drh9cd29642008-07-23 00:52:55 +00002703** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
drh6ed48bf2007-06-14 20:57:18 +00002704**
mihailimefc8e8a2008-06-21 16:47:09 +00002705** Return the number of columns in the result set returned by the
2706** [prepared statement]. This routine returns 0 if pStmt is an SQL
drh4ead1482008-06-26 18:16:05 +00002707** statement that does not return data (for example an [UPDATE]).
drh33c1be32008-01-30 16:16:14 +00002708**
drh8b39db12009-02-18 18:37:58 +00002709** Requirements:
2710** [H13711]
danielk197765904932004-05-26 06:18:37 +00002711*/
2712int sqlite3_column_count(sqlite3_stmt *pStmt);
2713
2714/*
drh9cd29642008-07-23 00:52:55 +00002715** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
drh6ed48bf2007-06-14 20:57:18 +00002716**
drh33c1be32008-01-30 16:16:14 +00002717** These routines return the name assigned to a particular column
drh4ead1482008-06-26 18:16:05 +00002718** in the result set of a [SELECT] statement. The sqlite3_column_name()
mihailimefc8e8a2008-06-21 16:47:09 +00002719** interface returns a pointer to a zero-terminated UTF-8 string
drhf5befa02007-12-06 02:42:07 +00002720** and sqlite3_column_name16() returns a pointer to a zero-terminated
mihailimefc8e8a2008-06-21 16:47:09 +00002721** UTF-16 string. The first parameter is the [prepared statement]
drh4ead1482008-06-26 18:16:05 +00002722** that implements the [SELECT] statement. The second parameter is the
mihailimefc8e8a2008-06-21 16:47:09 +00002723** column number. The leftmost column is number 0.
drh6ed48bf2007-06-14 20:57:18 +00002724**
mihailimefc8e8a2008-06-21 16:47:09 +00002725** The returned string pointer is valid until either the [prepared statement]
2726** is destroyed by [sqlite3_finalize()] or until the next call to
2727** sqlite3_column_name() or sqlite3_column_name16() on the same column.
drh4a50aac2007-08-23 02:47:53 +00002728**
drh33c1be32008-01-30 16:16:14 +00002729** If sqlite3_malloc() fails during the processing of either routine
drh4a50aac2007-08-23 02:47:53 +00002730** (for example during a conversion from UTF-8 to UTF-16) then a
2731** NULL pointer is returned.
drh33c1be32008-01-30 16:16:14 +00002732**
2733** The name of a result column is the value of the "AS" clause for
2734** that column, if there is an AS clause. If there is no AS clause
2735** then the name of the column is unspecified and may change from
2736** one release of SQLite to the next.
2737**
drh8b39db12009-02-18 18:37:58 +00002738** Requirements:
2739** [H13721] [H13723] [H13724] [H13725] [H13726] [H13727]
danielk197765904932004-05-26 06:18:37 +00002740*/
drh6ed48bf2007-06-14 20:57:18 +00002741const char *sqlite3_column_name(sqlite3_stmt*, int N);
2742const void *sqlite3_column_name16(sqlite3_stmt*, int N);
danielk197765904932004-05-26 06:18:37 +00002743
2744/*
drh9cd29642008-07-23 00:52:55 +00002745** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
drh6ed48bf2007-06-14 20:57:18 +00002746**
drh33c1be32008-01-30 16:16:14 +00002747** These routines provide a means to determine what column of what
drh4ead1482008-06-26 18:16:05 +00002748** table in which database a result of a [SELECT] statement comes from.
drh33c1be32008-01-30 16:16:14 +00002749** The name of the database or table or column can be returned as
mihailimebe796c2008-06-21 20:11:17 +00002750** either a UTF-8 or UTF-16 string. The _database_ routines return
drhbf2564f2007-06-21 15:25:05 +00002751** the database name, the _table_ routines return the table name, and
drh33c1be32008-01-30 16:16:14 +00002752** the origin_ routines return the column name.
mihailim1c492652008-06-21 18:02:16 +00002753** The returned string is valid until the [prepared statement] is destroyed
2754** using [sqlite3_finalize()] or until the same information is requested
drhbf2564f2007-06-21 15:25:05 +00002755** again in a different encoding.
2756**
drh33c1be32008-01-30 16:16:14 +00002757** The names returned are the original un-aliased names of the
drhbf2564f2007-06-21 15:25:05 +00002758** database, table, and column.
drh6ed48bf2007-06-14 20:57:18 +00002759**
drh33c1be32008-01-30 16:16:14 +00002760** The first argument to the following calls is a [prepared statement].
mihailim1c492652008-06-21 18:02:16 +00002761** These functions return information about the Nth column returned by
danielk1977955de522006-02-10 02:27:42 +00002762** the statement, where N is the second function argument.
2763**
mihailim1c492652008-06-21 18:02:16 +00002764** If the Nth column returned by the statement is an expression or
2765** subquery and is not a column value, then all of these functions return
2766** NULL. These routine might also return NULL if a memory allocation error
2767** occurs. Otherwise, they return the name of the attached database, table
2768** and column that query result column was extracted from.
danielk1977955de522006-02-10 02:27:42 +00002769**
drh33c1be32008-01-30 16:16:14 +00002770** As with all other SQLite APIs, those postfixed with "16" return
drhfddfa2d2007-12-05 18:05:16 +00002771** UTF-16 encoded strings, the other functions return UTF-8. {END}
danielk19774b1ae992006-02-10 03:06:10 +00002772**
mihailim1c492652008-06-21 18:02:16 +00002773** These APIs are only available if the library was compiled with the
drh4ead1482008-06-26 18:16:05 +00002774** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
drh32bc3f62007-08-21 20:25:39 +00002775**
drh4766b292008-06-26 02:53:02 +00002776** {A13751}
drh32bc3f62007-08-21 20:25:39 +00002777** If two or more threads call one or more of these routines against the same
2778** prepared statement and column at the same time then the results are
2779** undefined.
drh33c1be32008-01-30 16:16:14 +00002780**
drh8b39db12009-02-18 18:37:58 +00002781** Requirements:
2782** [H13741] [H13742] [H13743] [H13744] [H13745] [H13746] [H13748]
drh33c1be32008-01-30 16:16:14 +00002783**
drh8b39db12009-02-18 18:37:58 +00002784** If two or more threads call one or more
2785** [sqlite3_column_database_name | column metadata interfaces]
2786** for the same [prepared statement] and result column
2787** at the same time then the results are undefined.
danielk1977955de522006-02-10 02:27:42 +00002788*/
2789const char *sqlite3_column_database_name(sqlite3_stmt*,int);
2790const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
2791const char *sqlite3_column_table_name(sqlite3_stmt*,int);
2792const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
2793const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
2794const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
2795
2796/*
drh9cd29642008-07-23 00:52:55 +00002797** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
drh6ed48bf2007-06-14 20:57:18 +00002798**
mihailim1c492652008-06-21 18:02:16 +00002799** The first parameter is a [prepared statement].
drh4ead1482008-06-26 18:16:05 +00002800** If this statement is a [SELECT] statement and the Nth column of the
2801** returned result set of that [SELECT] is a table column (not an
drh6ed48bf2007-06-14 20:57:18 +00002802** expression or subquery) then the declared type of the table
drh33c1be32008-01-30 16:16:14 +00002803** column is returned. If the Nth column of the result set is an
drh6ed48bf2007-06-14 20:57:18 +00002804** expression or subquery, then a NULL pointer is returned.
mihailim1c492652008-06-21 18:02:16 +00002805** The returned string is always UTF-8 encoded. {END}
2806**
2807** For example, given the database schema:
danielk197765904932004-05-26 06:18:37 +00002808**
2809** CREATE TABLE t1(c1 VARIANT);
2810**
mihailim1c492652008-06-21 18:02:16 +00002811** and the following statement to be compiled:
danielk197765904932004-05-26 06:18:37 +00002812**
danielk1977955de522006-02-10 02:27:42 +00002813** SELECT c1 + 1, c1 FROM t1;
danielk197765904932004-05-26 06:18:37 +00002814**
mihailim1c492652008-06-21 18:02:16 +00002815** this routine would return the string "VARIANT" for the second result
2816** column (i==1), and a NULL pointer for the first result column (i==0).
drh6ed48bf2007-06-14 20:57:18 +00002817**
2818** SQLite uses dynamic run-time typing. So just because a column
2819** is declared to contain a particular type does not mean that the
2820** data stored in that column is of the declared type. SQLite is
2821** strongly typed, but the typing is dynamic not static. Type
2822** is associated with individual values, not with the containers
2823** used to hold those values.
drh33c1be32008-01-30 16:16:14 +00002824**
drh8b39db12009-02-18 18:37:58 +00002825** Requirements:
2826** [H13761] [H13762] [H13763]
danielk197765904932004-05-26 06:18:37 +00002827*/
drh33c1be32008-01-30 16:16:14 +00002828const char *sqlite3_column_decltype(sqlite3_stmt*,int);
danielk197765904932004-05-26 06:18:37 +00002829const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
2830
mihailimebe796c2008-06-21 20:11:17 +00002831/*
drh9cd29642008-07-23 00:52:55 +00002832** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
danielk1977106bb232004-05-21 10:08:53 +00002833**
mihailim1c492652008-06-21 18:02:16 +00002834** After a [prepared statement] has been prepared using either
2835** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
2836** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
2837** must be called one or more times to evaluate the statement.
danielk1977106bb232004-05-21 10:08:53 +00002838**
mihailim1c492652008-06-21 18:02:16 +00002839** The details of the behavior of the sqlite3_step() interface depend
drh6ed48bf2007-06-14 20:57:18 +00002840** on whether the statement was prepared using the newer "v2" interface
2841** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
2842** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
2843** new "v2" interface is recommended for new applications but the legacy
2844** interface will continue to be supported.
danielk1977106bb232004-05-21 10:08:53 +00002845**
mihailimebe796c2008-06-21 20:11:17 +00002846** In the legacy interface, the return value will be either [SQLITE_BUSY],
drh6ed48bf2007-06-14 20:57:18 +00002847** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
mihailim1c492652008-06-21 18:02:16 +00002848** With the "v2" interface, any of the other [result codes] or
2849** [extended result codes] might be returned as well.
drh6ed48bf2007-06-14 20:57:18 +00002850**
2851** [SQLITE_BUSY] means that the database engine was unable to acquire the
drh4ead1482008-06-26 18:16:05 +00002852** database locks it needs to do its job. If the statement is a [COMMIT]
drh6ed48bf2007-06-14 20:57:18 +00002853** or occurs outside of an explicit transaction, then you can retry the
drh4ead1482008-06-26 18:16:05 +00002854** statement. If the statement is not a [COMMIT] and occurs within a
drh6ed48bf2007-06-14 20:57:18 +00002855** explicit transaction then you should rollback the transaction before
2856** continuing.
2857**
2858** [SQLITE_DONE] means that the statement has finished executing
danielk1977106bb232004-05-21 10:08:53 +00002859** successfully. sqlite3_step() should not be called again on this virtual
drh6ed48bf2007-06-14 20:57:18 +00002860** machine without first calling [sqlite3_reset()] to reset the virtual
2861** machine back to its initial state.
danielk1977106bb232004-05-21 10:08:53 +00002862**
mihailim1c492652008-06-21 18:02:16 +00002863** If the SQL statement being executed returns any data, then [SQLITE_ROW]
2864** is returned each time a new row of data is ready for processing by the
2865** caller. The values may be accessed using the [column access functions].
drh6ed48bf2007-06-14 20:57:18 +00002866** sqlite3_step() is called again to retrieve the next row of data.
mihailim1c492652008-06-21 18:02:16 +00002867**
drh6ed48bf2007-06-14 20:57:18 +00002868** [SQLITE_ERROR] means that a run-time error (such as a constraint
danielk1977106bb232004-05-21 10:08:53 +00002869** violation) has occurred. sqlite3_step() should not be called again on
drh6ed48bf2007-06-14 20:57:18 +00002870** the VM. More information may be found by calling [sqlite3_errmsg()].
mihailim1c492652008-06-21 18:02:16 +00002871** With the legacy interface, a more specific error code (for example,
drh6ed48bf2007-06-14 20:57:18 +00002872** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
2873** can be obtained by calling [sqlite3_reset()] on the
drh33c1be32008-01-30 16:16:14 +00002874** [prepared statement]. In the "v2" interface,
drh6ed48bf2007-06-14 20:57:18 +00002875** the more specific error code is returned directly by sqlite3_step().
danielk1977106bb232004-05-21 10:08:53 +00002876**
drh6ed48bf2007-06-14 20:57:18 +00002877** [SQLITE_MISUSE] means that the this routine was called inappropriately.
drh33c1be32008-01-30 16:16:14 +00002878** Perhaps it was called on a [prepared statement] that has
mihailim1c492652008-06-21 18:02:16 +00002879** already been [sqlite3_finalize | finalized] or on one that had
drh6ed48bf2007-06-14 20:57:18 +00002880** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
2881** be the case that the same database connection is being used by two or
2882** more threads at the same moment in time.
2883**
mihailim1c492652008-06-21 18:02:16 +00002884** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
2885** API always returns a generic error code, [SQLITE_ERROR], following any
2886** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
2887** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
2888** specific [error codes] that better describes the error.
drh6ed48bf2007-06-14 20:57:18 +00002889** We admit that this is a goofy design. The problem has been fixed
2890** with the "v2" interface. If you prepare all of your SQL statements
2891** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
mihailim1c492652008-06-21 18:02:16 +00002892** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
2893** then the more specific [error codes] are returned directly
drh6ed48bf2007-06-14 20:57:18 +00002894** by sqlite3_step(). The use of the "v2" interface is recommended.
drh33c1be32008-01-30 16:16:14 +00002895**
drh8b39db12009-02-18 18:37:58 +00002896** Requirements:
2897** [H13202] [H15304] [H15306] [H15308] [H15310]
danielk1977106bb232004-05-21 10:08:53 +00002898*/
danielk197717240fd2004-05-26 00:07:25 +00002899int sqlite3_step(sqlite3_stmt*);
danielk1977106bb232004-05-21 10:08:53 +00002900
danielk1977106bb232004-05-21 10:08:53 +00002901/*
drh9cd29642008-07-23 00:52:55 +00002902** CAPI3REF: Number of columns in a result set {H13770} <S10700>
drh6ed48bf2007-06-14 20:57:18 +00002903**
mihailim1c492652008-06-21 18:02:16 +00002904** Returns the number of values in the current row of the result set.
danielk1977106bb232004-05-21 10:08:53 +00002905**
drh8b39db12009-02-18 18:37:58 +00002906** Requirements:
2907** [H13771] [H13772]
danielk1977106bb232004-05-21 10:08:53 +00002908*/
danielk197793d46752004-05-23 13:30:58 +00002909int sqlite3_data_count(sqlite3_stmt *pStmt);
danielk19774adee202004-05-08 08:23:19 +00002910
drh4f26d6c2004-05-26 23:25:30 +00002911/*
drhb25f9d82008-07-23 15:40:06 +00002912** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
drh33c1be32008-01-30 16:16:14 +00002913** KEYWORDS: SQLITE_TEXT
drh6ed48bf2007-06-14 20:57:18 +00002914**
drh9a247912008-07-22 18:45:08 +00002915** {H10266} Every value in SQLite has one of five fundamental datatypes:
drh6ed48bf2007-06-14 20:57:18 +00002916**
2917** <ul>
2918** <li> 64-bit signed integer
2919** <li> 64-bit IEEE floating point number
2920** <li> string
2921** <li> BLOB
2922** <li> NULL
drhfddfa2d2007-12-05 18:05:16 +00002923** </ul> {END}
drh6ed48bf2007-06-14 20:57:18 +00002924**
2925** These constants are codes for each of those types.
2926**
2927** Note that the SQLITE_TEXT constant was also used in SQLite version 2
2928** for a completely different meaning. Software that links against both
mihailim1c492652008-06-21 18:02:16 +00002929** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
drh6ed48bf2007-06-14 20:57:18 +00002930** SQLITE_TEXT.
drh4f26d6c2004-05-26 23:25:30 +00002931*/
drh9c054832004-05-31 18:51:57 +00002932#define SQLITE_INTEGER 1
2933#define SQLITE_FLOAT 2
drh9c054832004-05-31 18:51:57 +00002934#define SQLITE_BLOB 4
2935#define SQLITE_NULL 5
drh1e284f42004-10-06 15:52:01 +00002936#ifdef SQLITE_TEXT
2937# undef SQLITE_TEXT
2938#else
2939# define SQLITE_TEXT 3
2940#endif
2941#define SQLITE3_TEXT 3
2942
2943/*
drh9cd29642008-07-23 00:52:55 +00002944** CAPI3REF: Result Values From A Query {H13800} <S10700>
mihailim1c492652008-06-21 18:02:16 +00002945** KEYWORDS: {column access functions}
drh6ed48bf2007-06-14 20:57:18 +00002946**
drh33c1be32008-01-30 16:16:14 +00002947** These routines form the "result set query" interface.
2948**
mihailim1c492652008-06-21 18:02:16 +00002949** These routines return information about a single column of the current
2950** result row of a query. In every case the first argument is a pointer
2951** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
2952** that was returned from [sqlite3_prepare_v2()] or one of its variants)
2953** and the second argument is the index of the column for which information
2954** should be returned. The leftmost column of the result set has the index 0.
drhedc17552009-10-22 00:14:05 +00002955** The number of columns in the result can be determined using
2956** [sqlite3_column_count()].
danielk1977106bb232004-05-21 10:08:53 +00002957**
mihailim1c492652008-06-21 18:02:16 +00002958** If the SQL statement does not currently point to a valid row, or if the
2959** column index is out of range, the result is undefined.
drh32bc3f62007-08-21 20:25:39 +00002960** These routines may only be called when the most recent call to
2961** [sqlite3_step()] has returned [SQLITE_ROW] and neither
mihailim1c492652008-06-21 18:02:16 +00002962** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
drh32bc3f62007-08-21 20:25:39 +00002963** If any of these routines are called after [sqlite3_reset()] or
2964** [sqlite3_finalize()] or after [sqlite3_step()] has returned
2965** something other than [SQLITE_ROW], the results are undefined.
2966** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
2967** are called from a different thread while any of these routines
mihailim1c492652008-06-21 18:02:16 +00002968** are pending, then the results are undefined.
drh6ed48bf2007-06-14 20:57:18 +00002969**
mihailim1c492652008-06-21 18:02:16 +00002970** The sqlite3_column_type() routine returns the
drh6ed48bf2007-06-14 20:57:18 +00002971** [SQLITE_INTEGER | datatype code] for the initial data type
2972** of the result column. The returned value is one of [SQLITE_INTEGER],
2973** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
2974** returned by sqlite3_column_type() is only meaningful if no type
2975** conversions have occurred as described below. After a type conversion,
2976** the value returned by sqlite3_column_type() is undefined. Future
2977** versions of SQLite may change the behavior of sqlite3_column_type()
2978** following a type conversion.
2979**
mihailim1c492652008-06-21 18:02:16 +00002980** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
drh6ed48bf2007-06-14 20:57:18 +00002981** routine returns the number of bytes in that BLOB or string.
mihailimebe796c2008-06-21 20:11:17 +00002982** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
drh6ed48bf2007-06-14 20:57:18 +00002983** the string to UTF-8 and then returns the number of bytes.
2984** If the result is a numeric value then sqlite3_column_bytes() uses
mihailimebe796c2008-06-21 20:11:17 +00002985** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
drh6ed48bf2007-06-14 20:57:18 +00002986** the number of bytes in that string.
2987** The value returned does not include the zero terminator at the end
2988** of the string. For clarity: the value returned is the number of
2989** bytes in the string, not the number of characters.
2990**
drhc0b3abb2007-09-04 12:18:41 +00002991** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
drh33c1be32008-01-30 16:16:14 +00002992** even empty strings, are always zero terminated. The return
mihailim04bcc002008-06-22 10:21:27 +00002993** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
drhc0b3abb2007-09-04 12:18:41 +00002994** pointer, possibly even a NULL pointer.
2995**
drh6ed48bf2007-06-14 20:57:18 +00002996** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
mihailim1c492652008-06-21 18:02:16 +00002997** but leaves the result in UTF-16 in native byte order instead of UTF-8.
drh6ed48bf2007-06-14 20:57:18 +00002998** The zero terminator is not included in this count.
drh4f26d6c2004-05-26 23:25:30 +00002999**
drhaa28e142008-03-18 13:47:20 +00003000** The object returned by [sqlite3_column_value()] is an
3001** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
3002** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
3003** If the [unprotected sqlite3_value] object returned by
3004** [sqlite3_column_value()] is used in any other way, including calls
mihailim1c492652008-06-21 18:02:16 +00003005** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
3006** or [sqlite3_value_bytes()], then the behavior is undefined.
drhaa28e142008-03-18 13:47:20 +00003007**
drh4f26d6c2004-05-26 23:25:30 +00003008** These routines attempt to convert the value where appropriate. For
3009** example, if the internal representation is FLOAT and a text result
mihailim1c492652008-06-21 18:02:16 +00003010** is requested, [sqlite3_snprintf()] is used internally to perform the
3011** conversion automatically. The following table details the conversions
3012** that are applied:
drh4f26d6c2004-05-26 23:25:30 +00003013**
drh6ed48bf2007-06-14 20:57:18 +00003014** <blockquote>
3015** <table border="1">
drh8bacf972007-08-25 16:21:29 +00003016** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
drh4f26d6c2004-05-26 23:25:30 +00003017**
drh6ed48bf2007-06-14 20:57:18 +00003018** <tr><td> NULL <td> INTEGER <td> Result is 0
3019** <tr><td> NULL <td> FLOAT <td> Result is 0.0
3020** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
3021** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
3022** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
3023** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
mihailim1c492652008-06-21 18:02:16 +00003024** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
drh6ed48bf2007-06-14 20:57:18 +00003025** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
3026** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
3027** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
3028** <tr><td> TEXT <td> INTEGER <td> Use atoi()
3029** <tr><td> TEXT <td> FLOAT <td> Use atof()
3030** <tr><td> TEXT <td> BLOB <td> No change
3031** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
3032** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
3033** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
3034** </table>
3035** </blockquote>
drh4f26d6c2004-05-26 23:25:30 +00003036**
drh6ed48bf2007-06-14 20:57:18 +00003037** The table above makes reference to standard C library functions atoi()
3038** and atof(). SQLite does not really use these functions. It has its
shane26b34032008-05-23 17:21:09 +00003039** own equivalent internal routines. The atoi() and atof() names are
drh6ed48bf2007-06-14 20:57:18 +00003040** used in the table for brevity and because they are familiar to most
3041** C programmers.
3042**
3043** Note that when type conversions occur, pointers returned by prior
3044** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
mihailim1c492652008-06-21 18:02:16 +00003045** sqlite3_column_text16() may be invalidated.
drh6ed48bf2007-06-14 20:57:18 +00003046** Type conversions and pointer invalidations might occur
3047** in the following cases:
3048**
3049** <ul>
mihailim1c492652008-06-21 18:02:16 +00003050** <li> The initial content is a BLOB and sqlite3_column_text() or
3051** sqlite3_column_text16() is called. A zero-terminator might
3052** need to be added to the string.</li>
3053** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
3054** sqlite3_column_text16() is called. The content must be converted
3055** to UTF-16.</li>
3056** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
3057** sqlite3_column_text() is called. The content must be converted
3058** to UTF-8.</li>
drh6ed48bf2007-06-14 20:57:18 +00003059** </ul>
3060**
3061** Conversions between UTF-16be and UTF-16le are always done in place and do
3062** not invalidate a prior pointer, though of course the content of the buffer
3063** that the prior pointer points to will have been modified. Other kinds
mihailim1c492652008-06-21 18:02:16 +00003064** of conversion are done in place when it is possible, but sometimes they
3065** are not possible and in those cases prior pointers are invalidated.
drh6ed48bf2007-06-14 20:57:18 +00003066**
3067** The safest and easiest to remember policy is to invoke these routines
3068** in one of the following ways:
3069**
mihailim1c492652008-06-21 18:02:16 +00003070** <ul>
drh6ed48bf2007-06-14 20:57:18 +00003071** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
3072** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
3073** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
mihailim1c492652008-06-21 18:02:16 +00003074** </ul>
drh6ed48bf2007-06-14 20:57:18 +00003075**
mihailim1c492652008-06-21 18:02:16 +00003076** In other words, you should call sqlite3_column_text(),
3077** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
3078** into the desired format, then invoke sqlite3_column_bytes() or
3079** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
3080** to sqlite3_column_text() or sqlite3_column_blob() with calls to
3081** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
3082** with calls to sqlite3_column_bytes().
drh32bc3f62007-08-21 20:25:39 +00003083**
3084** The pointers returned are valid until a type conversion occurs as
3085** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
3086** [sqlite3_finalize()] is called. The memory space used to hold strings
mihailim04bcc002008-06-22 10:21:27 +00003087** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
mihailim1c492652008-06-21 18:02:16 +00003088** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
drh32bc3f62007-08-21 20:25:39 +00003089** [sqlite3_free()].
drh4a50aac2007-08-23 02:47:53 +00003090**
3091** If a memory allocation error occurs during the evaluation of any
3092** of these routines, a default value is returned. The default value
3093** is either the integer 0, the floating point number 0.0, or a NULL
3094** pointer. Subsequent calls to [sqlite3_errcode()] will return
3095** [SQLITE_NOMEM].
drh21ac7f92008-01-31 12:26:49 +00003096**
drh8b39db12009-02-18 18:37:58 +00003097** Requirements:
3098** [H13803] [H13806] [H13809] [H13812] [H13815] [H13818] [H13821] [H13824]
3099** [H13827] [H13830]
danielk1977106bb232004-05-21 10:08:53 +00003100*/
drhf4479502004-05-27 03:12:53 +00003101const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
3102int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
3103int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
3104double sqlite3_column_double(sqlite3_stmt*, int iCol);
3105int sqlite3_column_int(sqlite3_stmt*, int iCol);
drh6d2069d2007-08-14 01:58:53 +00003106sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
drhf4479502004-05-27 03:12:53 +00003107const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
3108const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
drh4f26d6c2004-05-26 23:25:30 +00003109int sqlite3_column_type(sqlite3_stmt*, int iCol);
drh4be8b512006-06-13 23:51:34 +00003110sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
danielk19774adee202004-05-08 08:23:19 +00003111
danielk197765904932004-05-26 06:18:37 +00003112/*
drhb25f9d82008-07-23 15:40:06 +00003113** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
drh6ed48bf2007-06-14 20:57:18 +00003114**
mihailimebe796c2008-06-21 20:11:17 +00003115** The sqlite3_finalize() function is called to delete a [prepared statement].
3116** If the statement was executed successfully or not executed at all, then
3117** SQLITE_OK is returned. If execution of the statement failed then an
3118** [error code] or [extended error code] is returned.
danielk197765904932004-05-26 06:18:37 +00003119**
3120** This routine can be called at any point during the execution of the
mihailimebe796c2008-06-21 20:11:17 +00003121** [prepared statement]. If the virtual machine has not
drh6ed48bf2007-06-14 20:57:18 +00003122** completed execution when this routine is called, that is like
mihailimebe796c2008-06-21 20:11:17 +00003123** encountering an error or an [sqlite3_interrupt | interrupt].
3124** Incomplete updates may be rolled back and transactions canceled,
3125** depending on the circumstances, and the
drh33c1be32008-01-30 16:16:14 +00003126** [error code] returned will be [SQLITE_ABORT].
3127**
drh8b39db12009-02-18 18:37:58 +00003128** Requirements:
3129** [H11302] [H11304]
danielk197765904932004-05-26 06:18:37 +00003130*/
3131int sqlite3_finalize(sqlite3_stmt *pStmt);
3132
3133/*
drh9cd29642008-07-23 00:52:55 +00003134** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
drh6ed48bf2007-06-14 20:57:18 +00003135**
mihailimebe796c2008-06-21 20:11:17 +00003136** The sqlite3_reset() function is called to reset a [prepared statement]
3137** object back to its initial state, ready to be re-executed.
danielk197765904932004-05-26 06:18:37 +00003138** Any SQL statement variables that had values bound to them using
drh6ed48bf2007-06-14 20:57:18 +00003139** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
3140** Use [sqlite3_clear_bindings()] to reset the bindings.
drh33c1be32008-01-30 16:16:14 +00003141**
drh9a247912008-07-22 18:45:08 +00003142** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
drh33c1be32008-01-30 16:16:14 +00003143** back to the beginning of its program.
3144**
drh9a247912008-07-22 18:45:08 +00003145** {H11334} If the most recent call to [sqlite3_step(S)] for the
drh33c1be32008-01-30 16:16:14 +00003146** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
3147** or if [sqlite3_step(S)] has never before been called on S,
3148** then [sqlite3_reset(S)] returns [SQLITE_OK].
3149**
drh9a247912008-07-22 18:45:08 +00003150** {H11336} If the most recent call to [sqlite3_step(S)] for the
drh33c1be32008-01-30 16:16:14 +00003151** [prepared statement] S indicated an error, then
3152** [sqlite3_reset(S)] returns an appropriate [error code].
3153**
drh9a247912008-07-22 18:45:08 +00003154** {H11338} The [sqlite3_reset(S)] interface does not change the values
mihailimebe796c2008-06-21 20:11:17 +00003155** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
danielk197765904932004-05-26 06:18:37 +00003156*/
3157int sqlite3_reset(sqlite3_stmt *pStmt);
3158
3159/*
drh9cd29642008-07-23 00:52:55 +00003160** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
mihailimefc8e8a2008-06-21 16:47:09 +00003161** KEYWORDS: {function creation routines}
3162** KEYWORDS: {application-defined SQL function}
3163** KEYWORDS: {application-defined SQL functions}
drh6ed48bf2007-06-14 20:57:18 +00003164**
mihailimebe796c2008-06-21 20:11:17 +00003165** These two functions (collectively known as "function creation routines")
3166** are used to add SQL functions or aggregates or to redefine the behavior
3167** of existing SQL functions or aggregates. The only difference between the
3168** two is that the second parameter, the name of the (scalar) function or
3169** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
3170** for sqlite3_create_function16().
danielk197765904932004-05-26 06:18:37 +00003171**
drh1c3cfc62008-03-08 12:37:30 +00003172** The first parameter is the [database connection] to which the SQL
mihailimebe796c2008-06-21 20:11:17 +00003173** function is to be added. If a single program uses more than one database
3174** connection internally, then SQL functions must be added individually to
3175** each database connection.
danielk197765904932004-05-26 06:18:37 +00003176**
mihailimebe796c2008-06-21 20:11:17 +00003177** The second parameter is the name of the SQL function to be created or
3178** redefined. The length of the name is limited to 255 bytes, exclusive of
3179** the zero-terminator. Note that the name length limit is in bytes, not
drh6ed48bf2007-06-14 20:57:18 +00003180** characters. Any attempt to create a function with a longer name
mihailimebe796c2008-06-21 20:11:17 +00003181** will result in [SQLITE_ERROR] being returned.
drh6ed48bf2007-06-14 20:57:18 +00003182**
drhc8075422008-09-10 13:09:23 +00003183** The third parameter (nArg)
3184** is the number of arguments that the SQL function or
drh97602f82009-05-24 11:07:49 +00003185** aggregate takes. If this parameter is -1, then the SQL function or
3186** aggregate may take any number of arguments between 0 and the limit
3187** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
drh09943b52009-05-24 21:59:27 +00003188** parameter is less than -1 or greater than 127 then the behavior is
3189** undefined.
danielk197765904932004-05-26 06:18:37 +00003190**
mihailimebe796c2008-06-21 20:11:17 +00003191** The fourth parameter, eTextRep, specifies what
drh6ed48bf2007-06-14 20:57:18 +00003192** [SQLITE_UTF8 | text encoding] this SQL function prefers for
3193** its parameters. Any SQL function implementation should be able to work
3194** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
drh6aa5f152009-08-19 15:57:07 +00003195** more efficient with one encoding than another. An application may
drh6d2069d2007-08-14 01:58:53 +00003196** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
drh6ed48bf2007-06-14 20:57:18 +00003197** times with the same function but with different values of eTextRep.
3198** When multiple implementations of the same function are available, SQLite
3199** will pick the one that involves the least amount of data conversion.
mihailimebe796c2008-06-21 20:11:17 +00003200** If there is only a single implementation which does not care what text
3201** encoding is used, then the fourth argument should be [SQLITE_ANY].
drh6ed48bf2007-06-14 20:57:18 +00003202**
mihailimebe796c2008-06-21 20:11:17 +00003203** The fifth parameter is an arbitrary pointer. The implementation of the
3204** function can gain access to this pointer using [sqlite3_user_data()].
danielk1977d02eb1f2004-06-06 09:44:03 +00003205**
danielk197765904932004-05-26 06:18:37 +00003206** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
mihailimebe796c2008-06-21 20:11:17 +00003207** pointers to C-language functions that implement the SQL function or
3208** aggregate. A scalar SQL function requires an implementation of the xFunc
3209** callback only, NULL pointers should be passed as the xStep and xFinal
3210** parameters. An aggregate SQL function requires an implementation of xStep
3211** and xFinal and NULL should be passed for xFunc. To delete an existing
3212** SQL function or aggregate, pass NULL for all three function callbacks.
drh6ed48bf2007-06-14 20:57:18 +00003213**
3214** It is permitted to register multiple implementations of the same
3215** functions with the same name but with either differing numbers of
shane26b34032008-05-23 17:21:09 +00003216** arguments or differing preferred text encodings. SQLite will use
drh6aa5f152009-08-19 15:57:07 +00003217** the implementation that most closely matches the way in which the
drhc8075422008-09-10 13:09:23 +00003218** SQL function is used. A function implementation with a non-negative
3219** nArg parameter is a better match than a function implementation with
3220** a negative nArg. A function where the preferred text encoding
3221** matches the database encoding is a better
3222** match than a function where the encoding is different.
3223** A function where the encoding difference is between UTF16le and UTF16be
3224** is a closer match than a function where the encoding difference is
3225** between UTF8 and UTF16.
3226**
3227** Built-in functions may be overloaded by new application-defined functions.
3228** The first application-defined function with a given name overrides all
3229** built-in functions in the same [database connection] with the same name.
3230** Subsequent application-defined functions of the same name only override
3231** prior application-defined functions that are an exact match for the
3232** number of parameters and preferred encoding.
3233**
3234** An application-defined function is permitted to call other
3235** SQLite interfaces. However, such calls must not
3236** close the database connection nor finalize or reset the prepared
3237** statement in which the function is running.
drh21ac7f92008-01-31 12:26:49 +00003238**
drh8b39db12009-02-18 18:37:58 +00003239** Requirements:
drh09943b52009-05-24 21:59:27 +00003240** [H16103] [H16106] [H16109] [H16112] [H16118] [H16121] [H16127]
drh8b39db12009-02-18 18:37:58 +00003241** [H16130] [H16133] [H16136] [H16139] [H16142]
danielk197765904932004-05-26 06:18:37 +00003242*/
3243int sqlite3_create_function(
drh33c1be32008-01-30 16:16:14 +00003244 sqlite3 *db,
danielk197765904932004-05-26 06:18:37 +00003245 const char *zFunctionName,
3246 int nArg,
3247 int eTextRep,
drh33c1be32008-01-30 16:16:14 +00003248 void *pApp,
danielk197765904932004-05-26 06:18:37 +00003249 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3250 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3251 void (*xFinal)(sqlite3_context*)
3252);
3253int sqlite3_create_function16(
drh33c1be32008-01-30 16:16:14 +00003254 sqlite3 *db,
danielk197765904932004-05-26 06:18:37 +00003255 const void *zFunctionName,
3256 int nArg,
3257 int eTextRep,
drh33c1be32008-01-30 16:16:14 +00003258 void *pApp,
danielk197765904932004-05-26 06:18:37 +00003259 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3260 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3261 void (*xFinal)(sqlite3_context*)
3262);
3263
3264/*
drh9cd29642008-07-23 00:52:55 +00003265** CAPI3REF: Text Encodings {H10267} <S50200> <H16100>
drh6ed48bf2007-06-14 20:57:18 +00003266**
3267** These constant define integer codes that represent the various
3268** text encodings supported by SQLite.
danielk197765904932004-05-26 06:18:37 +00003269*/
drh6ed48bf2007-06-14 20:57:18 +00003270#define SQLITE_UTF8 1
3271#define SQLITE_UTF16LE 2
3272#define SQLITE_UTF16BE 3
3273#define SQLITE_UTF16 4 /* Use native byte order */
3274#define SQLITE_ANY 5 /* sqlite3_create_function only */
3275#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
danielk197765904932004-05-26 06:18:37 +00003276
danielk19770ffba6b2004-05-24 09:10:10 +00003277/*
drhd5a68d32008-08-04 13:44:57 +00003278** CAPI3REF: Deprecated Functions
3279** DEPRECATED
drh6ed48bf2007-06-14 20:57:18 +00003280**
drhd5a68d32008-08-04 13:44:57 +00003281** These functions are [deprecated]. In order to maintain
3282** backwards compatibility with older code, these functions continue
3283** to be supported. However, new applications should avoid
drh6ed48bf2007-06-14 20:57:18 +00003284** the use of these functions. To help encourage people to avoid
shane7ba429a2008-11-10 17:08:49 +00003285** using these functions, we are not going to tell you what they do.
drh6ed48bf2007-06-14 20:57:18 +00003286*/
shaneeec556d2008-10-12 00:27:53 +00003287#ifndef SQLITE_OMIT_DEPRECATED
shanea79c3cc2008-08-11 17:27:01 +00003288SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
3289SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
3290SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
3291SQLITE_DEPRECATED int sqlite3_global_recover(void);
3292SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
3293SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
shaneeec556d2008-10-12 00:27:53 +00003294#endif
drh6ed48bf2007-06-14 20:57:18 +00003295
3296/*
drh9cd29642008-07-23 00:52:55 +00003297** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
drh6ed48bf2007-06-14 20:57:18 +00003298**
3299** The C-language implementation of SQL functions and aggregates uses
3300** this set of interface routines to access the parameter values on
3301** the function or aggregate.
3302**
3303** The xFunc (for scalar functions) or xStep (for aggregates) parameters
3304** to [sqlite3_create_function()] and [sqlite3_create_function16()]
3305** define callbacks that implement the SQL functions and aggregates.
3306** The 4th parameter to these callbacks is an array of pointers to
drhaa28e142008-03-18 13:47:20 +00003307** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
drh6ed48bf2007-06-14 20:57:18 +00003308** each parameter to the SQL function. These routines are used to
3309** extract values from the [sqlite3_value] objects.
3310**
drhaa28e142008-03-18 13:47:20 +00003311** These routines work only with [protected sqlite3_value] objects.
3312** Any attempt to use these routines on an [unprotected sqlite3_value]
3313** object results in undefined behavior.
3314**
mihailim1c492652008-06-21 18:02:16 +00003315** These routines work just like the corresponding [column access functions]
3316** except that these routines take a single [protected sqlite3_value] object
3317** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
drh6ed48bf2007-06-14 20:57:18 +00003318**
mihailimebe796c2008-06-21 20:11:17 +00003319** The sqlite3_value_text16() interface extracts a UTF-16 string
drh6ed48bf2007-06-14 20:57:18 +00003320** in the native byte-order of the host machine. The
3321** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
mihailimebe796c2008-06-21 20:11:17 +00003322** extract UTF-16 strings as big-endian and little-endian respectively.
drh6ed48bf2007-06-14 20:57:18 +00003323**
3324** The sqlite3_value_numeric_type() interface attempts to apply
3325** numeric affinity to the value. This means that an attempt is
3326** made to convert the value to an integer or floating point. If
drhf5befa02007-12-06 02:42:07 +00003327** such a conversion is possible without loss of information (in other
mihailimebe796c2008-06-21 20:11:17 +00003328** words, if the value is a string that looks like a number)
3329** then the conversion is performed. Otherwise no conversion occurs.
3330** The [SQLITE_INTEGER | datatype] after conversion is returned.
drh6ed48bf2007-06-14 20:57:18 +00003331**
mihailimebe796c2008-06-21 20:11:17 +00003332** Please pay particular attention to the fact that the pointer returned
3333** from [sqlite3_value_blob()], [sqlite3_value_text()], or
drh6ed48bf2007-06-14 20:57:18 +00003334** [sqlite3_value_text16()] can be invalidated by a subsequent call to
drh6d2069d2007-08-14 01:58:53 +00003335** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
mihailimebe796c2008-06-21 20:11:17 +00003336** or [sqlite3_value_text16()].
drhe53831d2007-08-17 01:14:38 +00003337**
3338** These routines must be called from the same thread as
drhaa28e142008-03-18 13:47:20 +00003339** the SQL function that supplied the [sqlite3_value*] parameters.
drhf5befa02007-12-06 02:42:07 +00003340**
drh8b39db12009-02-18 18:37:58 +00003341** Requirements:
3342** [H15103] [H15106] [H15109] [H15112] [H15115] [H15118] [H15121] [H15124]
3343** [H15127] [H15130] [H15133] [H15136]
danielk19770ffba6b2004-05-24 09:10:10 +00003344*/
drhf4479502004-05-27 03:12:53 +00003345const void *sqlite3_value_blob(sqlite3_value*);
3346int sqlite3_value_bytes(sqlite3_value*);
3347int sqlite3_value_bytes16(sqlite3_value*);
3348double sqlite3_value_double(sqlite3_value*);
3349int sqlite3_value_int(sqlite3_value*);
drh6d2069d2007-08-14 01:58:53 +00003350sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
drhf4479502004-05-27 03:12:53 +00003351const unsigned char *sqlite3_value_text(sqlite3_value*);
3352const void *sqlite3_value_text16(sqlite3_value*);
danielk1977d8123362004-06-12 09:25:12 +00003353const void *sqlite3_value_text16le(sqlite3_value*);
3354const void *sqlite3_value_text16be(sqlite3_value*);
danielk197793d46752004-05-23 13:30:58 +00003355int sqlite3_value_type(sqlite3_value*);
drh29d72102006-02-09 22:13:41 +00003356int sqlite3_value_numeric_type(sqlite3_value*);
danielk19770ffba6b2004-05-24 09:10:10 +00003357
3358/*
drh9cd29642008-07-23 00:52:55 +00003359** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
drh6ed48bf2007-06-14 20:57:18 +00003360**
3361** The implementation of aggregate SQL functions use this routine to allocate
mihailimebe796c2008-06-21 20:11:17 +00003362** a structure for storing their state.
3363**
3364** The first time the sqlite3_aggregate_context() routine is called for a
3365** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
3366** memory, and returns a pointer to it. On second and subsequent calls to
3367** sqlite3_aggregate_context() for the same aggregate function index,
3368** the same buffer is returned. The implementation of the aggregate can use
3369** the returned buffer to accumulate data.
danielk19770ae8b832004-05-25 12:05:56 +00003370**
drhafc91042008-02-21 02:09:45 +00003371** SQLite automatically frees the allocated buffer when the aggregate
3372** query concludes.
drh6ed48bf2007-06-14 20:57:18 +00003373**
mihailimebe796c2008-06-21 20:11:17 +00003374** The first parameter should be a copy of the
3375** [sqlite3_context | SQL function context] that is the first parameter
3376** to the callback routine that implements the aggregate function.
drhe53831d2007-08-17 01:14:38 +00003377**
3378** This routine must be called from the same thread in which
drh605264d2007-08-21 15:13:19 +00003379** the aggregate SQL function is running.
drhafc91042008-02-21 02:09:45 +00003380**
drh8b39db12009-02-18 18:37:58 +00003381** Requirements:
3382** [H16211] [H16213] [H16215] [H16217]
danielk19770ae8b832004-05-25 12:05:56 +00003383*/
drh4f26d6c2004-05-26 23:25:30 +00003384void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
danielk19777e18c252004-05-25 11:47:24 +00003385
3386/*
drh9cd29642008-07-23 00:52:55 +00003387** CAPI3REF: User Data For Functions {H16240} <S20200>
drh6ed48bf2007-06-14 20:57:18 +00003388**
drhafc91042008-02-21 02:09:45 +00003389** The sqlite3_user_data() interface returns a copy of
drhf5befa02007-12-06 02:42:07 +00003390** the pointer that was the pUserData parameter (the 5th parameter)
shane26b34032008-05-23 17:21:09 +00003391** of the [sqlite3_create_function()]
drhf5befa02007-12-06 02:42:07 +00003392** and [sqlite3_create_function16()] routines that originally
3393** registered the application defined function. {END}
drhe53831d2007-08-17 01:14:38 +00003394**
drhafc91042008-02-21 02:09:45 +00003395** This routine must be called from the same thread in which
drhf5befa02007-12-06 02:42:07 +00003396** the application-defined function is running.
drhafc91042008-02-21 02:09:45 +00003397**
drh8b39db12009-02-18 18:37:58 +00003398** Requirements:
3399** [H16243]
danielk19777e18c252004-05-25 11:47:24 +00003400*/
3401void *sqlite3_user_data(sqlite3_context*);
3402
3403/*
drhb25f9d82008-07-23 15:40:06 +00003404** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
drhfa4a4b92008-03-19 21:45:51 +00003405**
3406** The sqlite3_context_db_handle() interface returns a copy of
3407** the pointer to the [database connection] (the 1st parameter)
shane26b34032008-05-23 17:21:09 +00003408** of the [sqlite3_create_function()]
drhfa4a4b92008-03-19 21:45:51 +00003409** and [sqlite3_create_function16()] routines that originally
3410** registered the application defined function.
3411**
drh8b39db12009-02-18 18:37:58 +00003412** Requirements:
3413** [H16253]
drhfa4a4b92008-03-19 21:45:51 +00003414*/
3415sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
3416
3417/*
drh9cd29642008-07-23 00:52:55 +00003418** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
drh6ed48bf2007-06-14 20:57:18 +00003419**
3420** The following two functions may be used by scalar SQL functions to
mihailimebe796c2008-06-21 20:11:17 +00003421** associate metadata with argument values. If the same value is passed to
drh6ed48bf2007-06-14 20:57:18 +00003422** multiple invocations of the same SQL function during query execution, under
mihailimebe796c2008-06-21 20:11:17 +00003423** some circumstances the associated metadata may be preserved. This may
danielk1977682f68b2004-06-05 10:22:17 +00003424** be used, for example, to add a regular-expression matching scalar
3425** function. The compiled version of the regular expression is stored as
mihailimebe796c2008-06-21 20:11:17 +00003426** metadata associated with the SQL value passed as the regular expression
drh6ed48bf2007-06-14 20:57:18 +00003427** pattern. The compiled regular expression can be reused on multiple
3428** invocations of the same function so that the original pattern string
3429** does not need to be recompiled on each invocation.
danielk1977682f68b2004-06-05 10:22:17 +00003430**
mihailimebe796c2008-06-21 20:11:17 +00003431** The sqlite3_get_auxdata() interface returns a pointer to the metadata
drhf5befa02007-12-06 02:42:07 +00003432** associated by the sqlite3_set_auxdata() function with the Nth argument
mihailimebe796c2008-06-21 20:11:17 +00003433** value to the application-defined function. If no metadata has been ever
3434** been set for the Nth argument of the function, or if the corresponding
3435** function parameter has changed since the meta-data was set,
3436** then sqlite3_get_auxdata() returns a NULL pointer.
danielk1977682f68b2004-06-05 10:22:17 +00003437**
mihailimebe796c2008-06-21 20:11:17 +00003438** The sqlite3_set_auxdata() interface saves the metadata
3439** pointed to by its 3rd parameter as the metadata for the N-th
drhafc91042008-02-21 02:09:45 +00003440** argument of the application-defined function. Subsequent
drhf5befa02007-12-06 02:42:07 +00003441** calls to sqlite3_get_auxdata() might return this data, if it has
mihailimebe796c2008-06-21 20:11:17 +00003442** not been destroyed.
3443** If it is not NULL, SQLite will invoke the destructor
drhf5befa02007-12-06 02:42:07 +00003444** function given by the 4th parameter to sqlite3_set_auxdata() on
mihailimebe796c2008-06-21 20:11:17 +00003445** the metadata when the corresponding function parameter changes
drhafc91042008-02-21 02:09:45 +00003446** or when the SQL statement completes, whichever comes first.
3447**
mihailimebe796c2008-06-21 20:11:17 +00003448** SQLite is free to call the destructor and drop metadata on any
3449** parameter of any function at any time. The only guarantee is that
3450** the destructor will be called before the metadata is dropped.
danielk1977682f68b2004-06-05 10:22:17 +00003451**
mihailimebe796c2008-06-21 20:11:17 +00003452** In practice, metadata is preserved between function calls for
danielk1977682f68b2004-06-05 10:22:17 +00003453** expressions that are constant at compile time. This includes literal
3454** values and SQL variables.
drhe53831d2007-08-17 01:14:38 +00003455**
drhb21c8cd2007-08-21 19:33:56 +00003456** These routines must be called from the same thread in which
3457** the SQL function is running.
drhafc91042008-02-21 02:09:45 +00003458**
drh8b39db12009-02-18 18:37:58 +00003459** Requirements:
3460** [H16272] [H16274] [H16276] [H16277] [H16278] [H16279]
danielk1977682f68b2004-06-05 10:22:17 +00003461*/
drhf5befa02007-12-06 02:42:07 +00003462void *sqlite3_get_auxdata(sqlite3_context*, int N);
3463void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
danielk1977682f68b2004-06-05 10:22:17 +00003464
drha2854222004-06-17 19:04:17 +00003465
3466/*
drhb25f9d82008-07-23 15:40:06 +00003467** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
drh6ed48bf2007-06-14 20:57:18 +00003468**
mihailimebe796c2008-06-21 20:11:17 +00003469** These are special values for the destructor that is passed in as the
drh6ed48bf2007-06-14 20:57:18 +00003470** final argument to routines like [sqlite3_result_blob()]. If the destructor
drha2854222004-06-17 19:04:17 +00003471** argument is SQLITE_STATIC, it means that the content pointer is constant
mihailimebe796c2008-06-21 20:11:17 +00003472** and will never change. It does not need to be destroyed. The
drha2854222004-06-17 19:04:17 +00003473** SQLITE_TRANSIENT value means that the content will likely change in
3474** the near future and that SQLite should make its own private copy of
3475** the content before returning.
drh6c9121a2007-01-26 00:51:43 +00003476**
3477** The typedef is necessary to work around problems in certain
3478** C++ compilers. See ticket #2191.
drha2854222004-06-17 19:04:17 +00003479*/
drh6c9121a2007-01-26 00:51:43 +00003480typedef void (*sqlite3_destructor_type)(void*);
3481#define SQLITE_STATIC ((sqlite3_destructor_type)0)
3482#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
danielk1977d8123362004-06-12 09:25:12 +00003483
danielk1977682f68b2004-06-05 10:22:17 +00003484/*
drh9cd29642008-07-23 00:52:55 +00003485** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200>
drh6ed48bf2007-06-14 20:57:18 +00003486**
3487** These routines are used by the xFunc or xFinal callbacks that
3488** implement SQL functions and aggregates. See
3489** [sqlite3_create_function()] and [sqlite3_create_function16()]
3490** for additional information.
3491**
mihailimebe796c2008-06-21 20:11:17 +00003492** These functions work very much like the [parameter binding] family of
3493** functions used to bind values to host parameters in prepared statements.
3494** Refer to the [SQL parameter] documentation for additional information.
drh6ed48bf2007-06-14 20:57:18 +00003495**
drhafc91042008-02-21 02:09:45 +00003496** The sqlite3_result_blob() interface sets the result from
mihailimebe796c2008-06-21 20:11:17 +00003497** an application-defined function to be the BLOB whose content is pointed
drhf5befa02007-12-06 02:42:07 +00003498** to by the second parameter and which is N bytes long where N is the
mihailimebe796c2008-06-21 20:11:17 +00003499** third parameter.
3500**
shane26b34032008-05-23 17:21:09 +00003501** The sqlite3_result_zeroblob() interfaces set the result of
mihailimebe796c2008-06-21 20:11:17 +00003502** the application-defined function to be a BLOB containing all zero
drhf5befa02007-12-06 02:42:07 +00003503** bytes and N bytes in size, where N is the value of the 2nd parameter.
drh6ed48bf2007-06-14 20:57:18 +00003504**
drhafc91042008-02-21 02:09:45 +00003505** The sqlite3_result_double() interface sets the result from
mihailimebe796c2008-06-21 20:11:17 +00003506** an application-defined function to be a floating point value specified
drhf5befa02007-12-06 02:42:07 +00003507** by its 2nd argument.
drhe53831d2007-08-17 01:14:38 +00003508**
drhafc91042008-02-21 02:09:45 +00003509** The sqlite3_result_error() and sqlite3_result_error16() functions
drhf5befa02007-12-06 02:42:07 +00003510** cause the implemented SQL function to throw an exception.
drhafc91042008-02-21 02:09:45 +00003511** SQLite uses the string pointed to by the
drhf5befa02007-12-06 02:42:07 +00003512** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
drhafc91042008-02-21 02:09:45 +00003513** as the text of an error message. SQLite interprets the error
mihailimebe796c2008-06-21 20:11:17 +00003514** message string from sqlite3_result_error() as UTF-8. SQLite
3515** interprets the string from sqlite3_result_error16() as UTF-16 in native
drhafc91042008-02-21 02:09:45 +00003516** byte order. If the third parameter to sqlite3_result_error()
drhf5befa02007-12-06 02:42:07 +00003517** or sqlite3_result_error16() is negative then SQLite takes as the error
3518** message all text up through the first zero character.
drhafc91042008-02-21 02:09:45 +00003519** If the third parameter to sqlite3_result_error() or
drhf5befa02007-12-06 02:42:07 +00003520** sqlite3_result_error16() is non-negative then SQLite takes that many
3521** bytes (not characters) from the 2nd parameter as the error message.
drhafc91042008-02-21 02:09:45 +00003522** The sqlite3_result_error() and sqlite3_result_error16()
mihailimebe796c2008-06-21 20:11:17 +00003523** routines make a private copy of the error message text before
drhafc91042008-02-21 02:09:45 +00003524** they return. Hence, the calling function can deallocate or
drhf5befa02007-12-06 02:42:07 +00003525** modify the text after they return without harm.
drh69544ec2008-02-06 14:11:34 +00003526** The sqlite3_result_error_code() function changes the error code
3527** returned by SQLite as a result of an error in a function. By default,
drh00e087b2008-04-10 17:14:07 +00003528** the error code is SQLITE_ERROR. A subsequent call to sqlite3_result_error()
3529** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
drhf5befa02007-12-06 02:42:07 +00003530**
mihailimebe796c2008-06-21 20:11:17 +00003531** The sqlite3_result_toobig() interface causes SQLite to throw an error
3532** indicating that a string or BLOB is to long to represent.
3533**
3534** The sqlite3_result_nomem() interface causes SQLite to throw an error
3535** indicating that a memory allocation failed.
drhf5befa02007-12-06 02:42:07 +00003536**
drhafc91042008-02-21 02:09:45 +00003537** The sqlite3_result_int() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003538** of the application-defined function to be the 32-bit signed integer
3539** value given in the 2nd argument.
drhafc91042008-02-21 02:09:45 +00003540** The sqlite3_result_int64() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003541** of the application-defined function to be the 64-bit signed integer
3542** value given in the 2nd argument.
3543**
drhafc91042008-02-21 02:09:45 +00003544** The sqlite3_result_null() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003545** of the application-defined function to be NULL.
3546**
mihailimebe796c2008-06-21 20:11:17 +00003547** The sqlite3_result_text(), sqlite3_result_text16(),
drhf5befa02007-12-06 02:42:07 +00003548** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
3549** set the return value of the application-defined function to be
3550** a text string which is represented as UTF-8, UTF-16 native byte order,
3551** UTF-16 little endian, or UTF-16 big endian, respectively.
drhafc91042008-02-21 02:09:45 +00003552** SQLite takes the text result from the application from
drhf5befa02007-12-06 02:42:07 +00003553** the 2nd parameter of the sqlite3_result_text* interfaces.
drhafc91042008-02-21 02:09:45 +00003554** If the 3rd parameter to the sqlite3_result_text* interfaces
mihailimebe796c2008-06-21 20:11:17 +00003555** is negative, then SQLite takes result text from the 2nd parameter
drhf5befa02007-12-06 02:42:07 +00003556** through the first zero character.
drhafc91042008-02-21 02:09:45 +00003557** If the 3rd parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003558** is non-negative, then as many bytes (not characters) of the text
3559** pointed to by the 2nd parameter are taken as the application-defined
3560** function result.
drhafc91042008-02-21 02:09:45 +00003561** If the 4th parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003562** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
mihailimebe796c2008-06-21 20:11:17 +00003563** function as the destructor on the text or BLOB result when it has
drhf5befa02007-12-06 02:42:07 +00003564** finished using that result.
drh9e42f8a2009-08-13 20:15:29 +00003565** If the 4th parameter to the sqlite3_result_text* interfaces or to
mihailimebe796c2008-06-21 20:11:17 +00003566** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
3567** assumes that the text or BLOB result is in constant space and does not
drh9e42f8a2009-08-13 20:15:29 +00003568** copy the content of the parameter nor call a destructor on the content
3569** when it has finished using that result.
drhafc91042008-02-21 02:09:45 +00003570** If the 4th parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003571** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
3572** then SQLite makes a copy of the result into space obtained from
3573** from [sqlite3_malloc()] before it returns.
3574**
drhafc91042008-02-21 02:09:45 +00003575** The sqlite3_result_value() interface sets the result of
drhaa28e142008-03-18 13:47:20 +00003576** the application-defined function to be a copy the
3577** [unprotected sqlite3_value] object specified by the 2nd parameter. The
drhf5befa02007-12-06 02:42:07 +00003578** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
mihailimebe796c2008-06-21 20:11:17 +00003579** so that the [sqlite3_value] specified in the parameter may change or
drhf5befa02007-12-06 02:42:07 +00003580** be deallocated after sqlite3_result_value() returns without harm.
drhaa28e142008-03-18 13:47:20 +00003581** A [protected sqlite3_value] object may always be used where an
3582** [unprotected sqlite3_value] object is required, so either
3583** kind of [sqlite3_value] object can be used with this interface.
drhf5befa02007-12-06 02:42:07 +00003584**
mihailimebe796c2008-06-21 20:11:17 +00003585** If these routines are called from within the different thread
shane26b34032008-05-23 17:21:09 +00003586** than the one containing the application-defined function that received
drhf5befa02007-12-06 02:42:07 +00003587** the [sqlite3_context] pointer, the results are undefined.
drhafc91042008-02-21 02:09:45 +00003588**
drh8b39db12009-02-18 18:37:58 +00003589** Requirements:
3590** [H16403] [H16406] [H16409] [H16412] [H16415] [H16418] [H16421] [H16424]
3591** [H16427] [H16430] [H16433] [H16436] [H16439] [H16442] [H16445] [H16448]
3592** [H16451] [H16454] [H16457] [H16460] [H16463]
danielk19777e18c252004-05-25 11:47:24 +00003593*/
danielk1977d8123362004-06-12 09:25:12 +00003594void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
drh4f26d6c2004-05-26 23:25:30 +00003595void sqlite3_result_double(sqlite3_context*, double);
danielk19777e18c252004-05-25 11:47:24 +00003596void sqlite3_result_error(sqlite3_context*, const char*, int);
3597void sqlite3_result_error16(sqlite3_context*, const void*, int);
drh6ed48bf2007-06-14 20:57:18 +00003598void sqlite3_result_error_toobig(sqlite3_context*);
danielk1977a1644fd2007-08-29 12:31:25 +00003599void sqlite3_result_error_nomem(sqlite3_context*);
drh69544ec2008-02-06 14:11:34 +00003600void sqlite3_result_error_code(sqlite3_context*, int);
drh4f26d6c2004-05-26 23:25:30 +00003601void sqlite3_result_int(sqlite3_context*, int);
drh6d2069d2007-08-14 01:58:53 +00003602void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
drh4f26d6c2004-05-26 23:25:30 +00003603void sqlite3_result_null(sqlite3_context*);
danielk1977d8123362004-06-12 09:25:12 +00003604void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
3605void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
3606void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
3607void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
drh4f26d6c2004-05-26 23:25:30 +00003608void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
drhb026e052007-05-02 01:34:31 +00003609void sqlite3_result_zeroblob(sqlite3_context*, int n);
drhf9b596e2004-05-26 16:54:42 +00003610
drh52619df2004-06-11 17:48:02 +00003611/*
drh9cd29642008-07-23 00:52:55 +00003612** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
drh6ed48bf2007-06-14 20:57:18 +00003613**
3614** These functions are used to add new collation sequences to the
mihailimebe796c2008-06-21 20:11:17 +00003615** [database connection] specified as the first argument.
danielk19777cedc8d2004-06-10 10:50:08 +00003616**
3617** The name of the new collation sequence is specified as a UTF-8 string
drh6ed48bf2007-06-14 20:57:18 +00003618** for sqlite3_create_collation() and sqlite3_create_collation_v2()
drhafc91042008-02-21 02:09:45 +00003619** and a UTF-16 string for sqlite3_create_collation16(). In all cases
drh6ed48bf2007-06-14 20:57:18 +00003620** the name is passed as the second function argument.
danielk19777cedc8d2004-06-10 10:50:08 +00003621**
drh4145f832007-10-12 18:30:12 +00003622** The third argument may be one of the constants [SQLITE_UTF8],
drh51c7d862009-04-27 18:46:06 +00003623** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
danielk19777cedc8d2004-06-10 10:50:08 +00003624** routine expects to be passed pointers to strings encoded using UTF-8,
mihailimebe796c2008-06-21 20:11:17 +00003625** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
drh51c7d862009-04-27 18:46:06 +00003626** third argument might also be [SQLITE_UTF16] to indicate that the routine
3627** expects pointers to be UTF-16 strings in the native byte order, or the
3628** argument can be [SQLITE_UTF16_ALIGNED] if the
drh4145f832007-10-12 18:30:12 +00003629** the routine expects pointers to 16-bit word aligned strings
drh51c7d862009-04-27 18:46:06 +00003630** of UTF-16 in the native byte order.
danielk19777cedc8d2004-06-10 10:50:08 +00003631**
3632** A pointer to the user supplied routine must be passed as the fifth
drhafc91042008-02-21 02:09:45 +00003633** argument. If it is NULL, this is the same as deleting the collation
drhf5befa02007-12-06 02:42:07 +00003634** sequence (so that SQLite cannot call it anymore).
mihailimebe796c2008-06-21 20:11:17 +00003635** Each time the application supplied function is invoked, it is passed
3636** as its first parameter a copy of the void* passed as the fourth argument
3637** to sqlite3_create_collation() or sqlite3_create_collation16().
danielk19777cedc8d2004-06-10 10:50:08 +00003638**
drhf5befa02007-12-06 02:42:07 +00003639** The remaining arguments to the application-supplied routine are two strings,
drh33c1be32008-01-30 16:16:14 +00003640** each represented by a (length, data) pair and encoded in the encoding
danielk19777cedc8d2004-06-10 10:50:08 +00003641** that was passed as the third argument when the collation sequence was
mihailim04bcc002008-06-22 10:21:27 +00003642** registered. {END} The application defined collation routine should
mihailimebe796c2008-06-21 20:11:17 +00003643** return negative, zero or positive if the first string is less than,
3644** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
drh6ed48bf2007-06-14 20:57:18 +00003645**
3646** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
shane26b34032008-05-23 17:21:09 +00003647** except that it takes an extra argument which is a destructor for
drhafc91042008-02-21 02:09:45 +00003648** the collation. The destructor is called when the collation is
drh6ed48bf2007-06-14 20:57:18 +00003649** destroyed and is passed a copy of the fourth parameter void* pointer
drhf5befa02007-12-06 02:42:07 +00003650** of the sqlite3_create_collation_v2().
mihailimebe796c2008-06-21 20:11:17 +00003651** Collations are destroyed when they are overridden by later calls to the
3652** collation creation functions or when the [database connection] is closed
3653** using [sqlite3_close()].
drhafc91042008-02-21 02:09:45 +00003654**
drh51c7d862009-04-27 18:46:06 +00003655** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
3656**
drh8b39db12009-02-18 18:37:58 +00003657** Requirements:
3658** [H16603] [H16604] [H16606] [H16609] [H16612] [H16615] [H16618] [H16621]
3659** [H16624] [H16627] [H16630]
danielk19777cedc8d2004-06-10 10:50:08 +00003660*/
danielk19770202b292004-06-09 09:55:16 +00003661int sqlite3_create_collation(
3662 sqlite3*,
3663 const char *zName,
danielk19777cedc8d2004-06-10 10:50:08 +00003664 int eTextRep,
danielk19770202b292004-06-09 09:55:16 +00003665 void*,
3666 int(*xCompare)(void*,int,const void*,int,const void*)
3667);
drh6ed48bf2007-06-14 20:57:18 +00003668int sqlite3_create_collation_v2(
3669 sqlite3*,
3670 const char *zName,
3671 int eTextRep,
3672 void*,
3673 int(*xCompare)(void*,int,const void*,int,const void*),
3674 void(*xDestroy)(void*)
3675);
danielk19770202b292004-06-09 09:55:16 +00003676int sqlite3_create_collation16(
3677 sqlite3*,
mihailimbda2e622008-06-23 11:23:14 +00003678 const void *zName,
danielk19777cedc8d2004-06-10 10:50:08 +00003679 int eTextRep,
danielk19770202b292004-06-09 09:55:16 +00003680 void*,
3681 int(*xCompare)(void*,int,const void*,int,const void*)
3682);
3683
danielk19777cedc8d2004-06-10 10:50:08 +00003684/*
drh9cd29642008-07-23 00:52:55 +00003685** CAPI3REF: Collation Needed Callbacks {H16700} <S20300>
danielk1977a393c032007-05-07 14:58:53 +00003686**
danielk19777cedc8d2004-06-10 10:50:08 +00003687** To avoid having to register all collation sequences before a database
3688** can be used, a single callback function may be registered with the
mihailimdc884822008-06-22 08:58:50 +00003689** [database connection] to be called whenever an undefined collation
3690** sequence is required.
danielk19777cedc8d2004-06-10 10:50:08 +00003691**
3692** If the function is registered using the sqlite3_collation_needed() API,
3693** then it is passed the names of undefined collation sequences as strings
drh9a247912008-07-22 18:45:08 +00003694** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used,
mihailimdc884822008-06-22 08:58:50 +00003695** the names are passed as UTF-16 in machine native byte order.
3696** A call to either function replaces any existing callback.
danielk19777cedc8d2004-06-10 10:50:08 +00003697**
drhafc91042008-02-21 02:09:45 +00003698** When the callback is invoked, the first argument passed is a copy
danielk19777cedc8d2004-06-10 10:50:08 +00003699** of the second argument to sqlite3_collation_needed() or
drhafc91042008-02-21 02:09:45 +00003700** sqlite3_collation_needed16(). The second argument is the database
mihailimdc884822008-06-22 08:58:50 +00003701** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
3702** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
3703** sequence function required. The fourth parameter is the name of the
drhafc91042008-02-21 02:09:45 +00003704** required collation sequence.
danielk19777cedc8d2004-06-10 10:50:08 +00003705**
drh6ed48bf2007-06-14 20:57:18 +00003706** The callback function should register the desired collation using
3707** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
3708** [sqlite3_create_collation_v2()].
drhafc91042008-02-21 02:09:45 +00003709**
drh8b39db12009-02-18 18:37:58 +00003710** Requirements:
3711** [H16702] [H16704] [H16706]
danielk19777cedc8d2004-06-10 10:50:08 +00003712*/
3713int sqlite3_collation_needed(
3714 sqlite3*,
3715 void*,
3716 void(*)(void*,sqlite3*,int eTextRep,const char*)
3717);
3718int sqlite3_collation_needed16(
3719 sqlite3*,
3720 void*,
3721 void(*)(void*,sqlite3*,int eTextRep,const void*)
3722);
3723
drh2011d5f2004-07-22 02:40:37 +00003724/*
3725** Specify the key for an encrypted database. This routine should be
3726** called right after sqlite3_open().
3727**
3728** The code to implement this API is not available in the public release
3729** of SQLite.
3730*/
3731int sqlite3_key(
3732 sqlite3 *db, /* Database to be rekeyed */
3733 const void *pKey, int nKey /* The key */
3734);
3735
3736/*
3737** Change the key on an open database. If the current database is not
3738** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
3739** database is decrypted.
3740**
3741** The code to implement this API is not available in the public release
3742** of SQLite.
3743*/
3744int sqlite3_rekey(
3745 sqlite3 *db, /* Database to be rekeyed */
3746 const void *pKey, int nKey /* The new key */
3747);
danielk19770202b292004-06-09 09:55:16 +00003748
drhab3f9fe2004-08-14 17:10:10 +00003749/*
drhb25f9d82008-07-23 15:40:06 +00003750** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
drh6ed48bf2007-06-14 20:57:18 +00003751**
mihailimdc884822008-06-22 08:58:50 +00003752** The sqlite3_sleep() function causes the current thread to suspend execution
drhfddfa2d2007-12-05 18:05:16 +00003753** for at least a number of milliseconds specified in its parameter.
danielk1977600dd0b2005-01-20 01:14:23 +00003754**
mihailimdc884822008-06-22 08:58:50 +00003755** If the operating system does not support sleep requests with
3756** millisecond time resolution, then the time will be rounded up to
3757** the nearest second. The number of milliseconds of sleep actually
danielk1977600dd0b2005-01-20 01:14:23 +00003758** requested from the operating system is returned.
drh8bacf972007-08-25 16:21:29 +00003759**
drhafc91042008-02-21 02:09:45 +00003760** SQLite implements this interface by calling the xSleep()
3761** method of the default [sqlite3_vfs] object.
3762**
drh8b39db12009-02-18 18:37:58 +00003763** Requirements: [H10533] [H10536]
danielk1977600dd0b2005-01-20 01:14:23 +00003764*/
3765int sqlite3_sleep(int);
3766
3767/*
drhb25f9d82008-07-23 15:40:06 +00003768** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
drhd89bd002005-01-22 03:03:54 +00003769**
drh6ed48bf2007-06-14 20:57:18 +00003770** If this global variable is made to point to a string which is
shane26b34032008-05-23 17:21:09 +00003771** the name of a folder (a.k.a. directory), then all temporary files
drhab3f9fe2004-08-14 17:10:10 +00003772** created by SQLite will be placed in that directory. If this variable
mihailimdc884822008-06-22 08:58:50 +00003773** is a NULL pointer, then SQLite performs a search for an appropriate
3774** temporary file directory.
drhab3f9fe2004-08-14 17:10:10 +00003775**
drh1a25f112009-04-06 15:55:03 +00003776** It is not safe to read or modify this variable in more than one
3777** thread at a time. It is not safe to read or modify this variable
3778** if a [database connection] is being used at the same time in a separate
3779** thread.
3780** It is intended that this variable be set once
drh4ff7fa02007-09-01 18:17:21 +00003781** as part of process initialization and before any SQLite interface
drh1a25f112009-04-06 15:55:03 +00003782** routines have been called and that this variable remain unchanged
3783** thereafter.
3784**
3785** The [temp_store_directory pragma] may modify this variable and cause
3786** it to point to memory obtained from [sqlite3_malloc]. Furthermore,
3787** the [temp_store_directory pragma] always assumes that any string
3788** that this variable points to is held in memory obtained from
3789** [sqlite3_malloc] and the pragma may attempt to free that memory
3790** using [sqlite3_free].
3791** Hence, if this variable is modified directly, either it should be
3792** made NULL or made to point to memory obtained from [sqlite3_malloc]
3793** or else the use of the [temp_store_directory pragma] should be avoided.
drhab3f9fe2004-08-14 17:10:10 +00003794*/
drh73be5012007-08-08 12:11:21 +00003795SQLITE_EXTERN char *sqlite3_temp_directory;
drhab3f9fe2004-08-14 17:10:10 +00003796
danielk19776b456a22005-03-21 04:04:02 +00003797/*
drh9cd29642008-07-23 00:52:55 +00003798** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
mihailim15194222008-06-22 09:55:14 +00003799** KEYWORDS: {autocommit mode}
danielk19776b456a22005-03-21 04:04:02 +00003800**
shane26b34032008-05-23 17:21:09 +00003801** The sqlite3_get_autocommit() interface returns non-zero or
drhf5befa02007-12-06 02:42:07 +00003802** zero if the given database connection is or is not in autocommit mode,
mihailim04bcc002008-06-22 10:21:27 +00003803** respectively. Autocommit mode is on by default.
mihailimdc884822008-06-22 08:58:50 +00003804** Autocommit mode is disabled by a [BEGIN] statement.
shane26b34032008-05-23 17:21:09 +00003805** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
drhe30f4422007-08-21 16:15:55 +00003806**
drh7c3472a2007-10-03 20:15:28 +00003807** If certain kinds of errors occur on a statement within a multi-statement
mihailimdc884822008-06-22 08:58:50 +00003808** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
drh7c3472a2007-10-03 20:15:28 +00003809** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
drh33c1be32008-01-30 16:16:14 +00003810** transaction might be rolled back automatically. The only way to
mihailimdc884822008-06-22 08:58:50 +00003811** find out whether SQLite automatically rolled back the transaction after
drh33c1be32008-01-30 16:16:14 +00003812** an error is to use this function.
drh7c3472a2007-10-03 20:15:28 +00003813**
drh8b39db12009-02-18 18:37:58 +00003814** If another thread changes the autocommit status of the database
3815** connection while this routine is running, then the return value
3816** is undefined.
drh33c1be32008-01-30 16:16:14 +00003817**
drh8b39db12009-02-18 18:37:58 +00003818** Requirements: [H12931] [H12932] [H12933] [H12934]
drh3e1d8e62005-05-26 16:23:34 +00003819*/
3820int sqlite3_get_autocommit(sqlite3*);
3821
drh51942bc2005-06-12 22:01:42 +00003822/*
drhb25f9d82008-07-23 15:40:06 +00003823** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
drh6ed48bf2007-06-14 20:57:18 +00003824**
mihailimdc884822008-06-22 08:58:50 +00003825** The sqlite3_db_handle interface returns the [database connection] handle
drh62b5d2d2009-02-03 18:47:22 +00003826** to which a [prepared statement] belongs. The [database connection]
3827** returned by sqlite3_db_handle is the same [database connection] that was the first argument
mihailimdc884822008-06-22 08:58:50 +00003828** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
3829** create the statement in the first place.
drhafc91042008-02-21 02:09:45 +00003830**
drh8b39db12009-02-18 18:37:58 +00003831** Requirements: [H13123]
drh51942bc2005-06-12 22:01:42 +00003832*/
3833sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
drh3e1d8e62005-05-26 16:23:34 +00003834
drhbb5a9c32008-06-19 02:52:25 +00003835/*
drhb25f9d82008-07-23 15:40:06 +00003836** CAPI3REF: Find the next prepared statement {H13140} <S60600>
drhbb5a9c32008-06-19 02:52:25 +00003837**
mihailimdc884822008-06-22 08:58:50 +00003838** This interface returns a pointer to the next [prepared statement] after
3839** pStmt associated with the [database connection] pDb. If pStmt is NULL
3840** then this interface returns a pointer to the first prepared statement
3841** associated with the database connection pDb. If no prepared statement
3842** satisfies the conditions of this routine, it returns NULL.
drhbb5a9c32008-06-19 02:52:25 +00003843**
drh8b39db12009-02-18 18:37:58 +00003844** The [database connection] pointer D in a call to
3845** [sqlite3_next_stmt(D,S)] must refer to an open database
3846** connection and in particular must not be a NULL pointer.
drhbb5a9c32008-06-19 02:52:25 +00003847**
drh8b39db12009-02-18 18:37:58 +00003848** Requirements: [H13143] [H13146] [H13149] [H13152]
drhbb5a9c32008-06-19 02:52:25 +00003849*/
3850sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
3851
drhb37df7b2005-10-13 02:09:49 +00003852/*
drh9cd29642008-07-23 00:52:55 +00003853** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
drh6ed48bf2007-06-14 20:57:18 +00003854**
drhafc91042008-02-21 02:09:45 +00003855** The sqlite3_commit_hook() interface registers a callback
drhabda6112009-05-14 22:37:47 +00003856** function to be invoked whenever a transaction is [COMMIT | committed].
drhafc91042008-02-21 02:09:45 +00003857** Any callback set by a previous call to sqlite3_commit_hook()
drhf5befa02007-12-06 02:42:07 +00003858** for the same database connection is overridden.
drhafc91042008-02-21 02:09:45 +00003859** The sqlite3_rollback_hook() interface registers a callback
drhabda6112009-05-14 22:37:47 +00003860** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
drhafc91042008-02-21 02:09:45 +00003861** Any callback set by a previous call to sqlite3_commit_hook()
drhf5befa02007-12-06 02:42:07 +00003862** for the same database connection is overridden.
mihailimdc884822008-06-22 08:58:50 +00003863** The pArg argument is passed through to the callback.
3864** If the callback on a commit hook function returns non-zero,
3865** then the commit is converted into a rollback.
drh6ed48bf2007-06-14 20:57:18 +00003866**
drhafc91042008-02-21 02:09:45 +00003867** If another function was previously registered, its
drhf5befa02007-12-06 02:42:07 +00003868** pArg value is returned. Otherwise NULL is returned.
drh6ed48bf2007-06-14 20:57:18 +00003869**
drhc8075422008-09-10 13:09:23 +00003870** The callback implementation must not do anything that will modify
3871** the database connection that invoked the callback. Any actions
3872** to modify the database connection must be deferred until after the
3873** completion of the [sqlite3_step()] call that triggered the commit
3874** or rollback hook in the first place.
3875** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3876** database connections for the meaning of "modify" in this paragraph.
3877**
drhafc91042008-02-21 02:09:45 +00003878** Registering a NULL function disables the callback.
drh6ed48bf2007-06-14 20:57:18 +00003879**
drhabda6112009-05-14 22:37:47 +00003880** When the commit hook callback routine returns zero, the [COMMIT]
3881** operation is allowed to continue normally. If the commit hook
3882** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
3883** The rollback hook is invoked on a rollback that results from a commit
3884** hook returning non-zero, just as it would be with any other rollback.
3885**
mihailimdc884822008-06-22 08:58:50 +00003886** For the purposes of this API, a transaction is said to have been
drh6ed48bf2007-06-14 20:57:18 +00003887** rolled back if an explicit "ROLLBACK" statement is executed, or
drhf5befa02007-12-06 02:42:07 +00003888** an error or constraint causes an implicit rollback to occur.
drhafc91042008-02-21 02:09:45 +00003889** The rollback callback is not invoked if a transaction is
drhf5befa02007-12-06 02:42:07 +00003890** automatically rolled back because the database connection is closed.
drhafc91042008-02-21 02:09:45 +00003891** The rollback callback is not invoked if a transaction is
drhf5befa02007-12-06 02:42:07 +00003892** rolled back because a commit callback returned non-zero.
drhafc91042008-02-21 02:09:45 +00003893** <todo> Check on this </todo>
drh6ed48bf2007-06-14 20:57:18 +00003894**
drhabda6112009-05-14 22:37:47 +00003895** See also the [sqlite3_update_hook()] interface.
3896**
drh8b39db12009-02-18 18:37:58 +00003897** Requirements:
3898** [H12951] [H12952] [H12953] [H12954] [H12955]
3899** [H12961] [H12962] [H12963] [H12964]
drh6ed48bf2007-06-14 20:57:18 +00003900*/
3901void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
3902void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
3903
3904/*
drh9cd29642008-07-23 00:52:55 +00003905** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
drh6ed48bf2007-06-14 20:57:18 +00003906**
mihailimdc884822008-06-22 08:58:50 +00003907** The sqlite3_update_hook() interface registers a callback function
3908** with the [database connection] identified by the first argument
3909** to be invoked whenever a row is updated, inserted or deleted.
3910** Any callback set by a previous call to this function
3911** for the same database connection is overridden.
danielk197794eb6a12005-12-15 15:22:08 +00003912**
mihailimdc884822008-06-22 08:58:50 +00003913** The second argument is a pointer to the function to invoke when a
3914** row is updated, inserted or deleted.
3915** The first argument to the callback is a copy of the third argument
3916** to sqlite3_update_hook().
3917** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
3918** or [SQLITE_UPDATE], depending on the operation that caused the callback
3919** to be invoked.
3920** The third and fourth arguments to the callback contain pointers to the
3921** database and table name containing the affected row.
drh49c3d572008-12-15 22:51:38 +00003922** The final callback parameter is the [rowid] of the row.
3923** In the case of an update, this is the [rowid] after the update takes place.
danielk197794eb6a12005-12-15 15:22:08 +00003924**
drhafc91042008-02-21 02:09:45 +00003925** The update hook is not invoked when internal system tables are
danielk197794eb6a12005-12-15 15:22:08 +00003926** modified (i.e. sqlite_master and sqlite_sequence).
danielk197771fd80b2005-12-16 06:54:01 +00003927**
drhabda6112009-05-14 22:37:47 +00003928** In the current implementation, the update hook
3929** is not invoked when duplication rows are deleted because of an
3930** [ON CONFLICT | ON CONFLICT REPLACE] clause. Nor is the update hook
3931** invoked when rows are deleted using the [truncate optimization].
3932** The exceptions defined in this paragraph might change in a future
3933** release of SQLite.
3934**
drhc8075422008-09-10 13:09:23 +00003935** The update hook implementation must not do anything that will modify
3936** the database connection that invoked the update hook. Any actions
3937** to modify the database connection must be deferred until after the
3938** completion of the [sqlite3_step()] call that triggered the update hook.
3939** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3940** database connections for the meaning of "modify" in this paragraph.
3941**
drhafc91042008-02-21 02:09:45 +00003942** If another function was previously registered, its pArg value
3943** is returned. Otherwise NULL is returned.
3944**
drhabda6112009-05-14 22:37:47 +00003945** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
3946** interfaces.
3947**
drh8b39db12009-02-18 18:37:58 +00003948** Requirements:
3949** [H12971] [H12973] [H12975] [H12977] [H12979] [H12981] [H12983] [H12986]
danielk197794eb6a12005-12-15 15:22:08 +00003950*/
danielk197771fd80b2005-12-16 06:54:01 +00003951void *sqlite3_update_hook(
danielk197794eb6a12005-12-15 15:22:08 +00003952 sqlite3*,
drh6d2069d2007-08-14 01:58:53 +00003953 void(*)(void *,int ,char const *,char const *,sqlite3_int64),
danielk197794eb6a12005-12-15 15:22:08 +00003954 void*
3955);
danielk197713a68c32005-12-15 10:11:30 +00003956
danielk1977f3f06bb2005-12-16 15:24:28 +00003957/*
drh9cd29642008-07-23 00:52:55 +00003958** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>
drhe33b0ed2009-08-06 17:40:45 +00003959** KEYWORDS: {shared cache}
danielk1977f3f06bb2005-12-16 15:24:28 +00003960**
drh6ed48bf2007-06-14 20:57:18 +00003961** This routine enables or disables the sharing of the database cache
mihailimdc884822008-06-22 08:58:50 +00003962** and schema data structures between [database connection | connections]
3963** to the same database. Sharing is enabled if the argument is true
3964** and disabled if the argument is false.
danielk1977f3f06bb2005-12-16 15:24:28 +00003965**
drhaff46972009-02-12 17:07:34 +00003966** Cache sharing is enabled and disabled for an entire process.
mihailimdc884822008-06-22 08:58:50 +00003967** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
3968** sharing was enabled or disabled for each thread separately.
drh6ed48bf2007-06-14 20:57:18 +00003969**
drhe30f4422007-08-21 16:15:55 +00003970** The cache sharing mode set by this interface effects all subsequent
3971** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
drhafc91042008-02-21 02:09:45 +00003972** Existing database connections continue use the sharing mode
3973** that was in effect at the time they were opened.
drh6ed48bf2007-06-14 20:57:18 +00003974**
mihailimdc884822008-06-22 08:58:50 +00003975** Virtual tables cannot be used with a shared cache. When shared
drh4ff7fa02007-09-01 18:17:21 +00003976** cache is enabled, the [sqlite3_create_module()] API used to register
drhafc91042008-02-21 02:09:45 +00003977** virtual tables will always return an error.
drh6ed48bf2007-06-14 20:57:18 +00003978**
mihailimdc884822008-06-22 08:58:50 +00003979** This routine returns [SQLITE_OK] if shared cache was enabled or disabled
3980** successfully. An [error code] is returned otherwise.
drh6ed48bf2007-06-14 20:57:18 +00003981**
drhafc91042008-02-21 02:09:45 +00003982** Shared cache is disabled by default. But this might change in
drh4ff7fa02007-09-01 18:17:21 +00003983** future releases of SQLite. Applications that care about shared
3984** cache setting should set it explicitly.
drhafc91042008-02-21 02:09:45 +00003985**
drhaff46972009-02-12 17:07:34 +00003986** See Also: [SQLite Shared-Cache Mode]
3987**
drh8b39db12009-02-18 18:37:58 +00003988** Requirements: [H10331] [H10336] [H10337] [H10339]
danielk1977aef0bf62005-12-30 16:28:01 +00003989*/
3990int sqlite3_enable_shared_cache(int);
3991
3992/*
drh9cd29642008-07-23 00:52:55 +00003993** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
drh6ed48bf2007-06-14 20:57:18 +00003994**
mihailim04bcc002008-06-22 10:21:27 +00003995** The sqlite3_release_memory() interface attempts to free N bytes
3996** of heap memory by deallocating non-essential memory allocations
3997** held by the database library. {END} Memory used to cache database
3998** pages to improve performance is an example of non-essential memory.
3999** sqlite3_release_memory() returns the number of bytes actually freed,
4000** which might be more or less than the amount requested.
drhafc91042008-02-21 02:09:45 +00004001**
drh8b39db12009-02-18 18:37:58 +00004002** Requirements: [H17341] [H17342]
danielk197752622822006-01-09 09:59:49 +00004003*/
4004int sqlite3_release_memory(int);
4005
4006/*
drh9cd29642008-07-23 00:52:55 +00004007** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
drh6ed48bf2007-06-14 20:57:18 +00004008**
mihailimdc884822008-06-22 08:58:50 +00004009** The sqlite3_soft_heap_limit() interface places a "soft" limit
4010** on the amount of heap memory that may be allocated by SQLite.
4011** If an internal allocation is requested that would exceed the
4012** soft heap limit, [sqlite3_release_memory()] is invoked one or
4013** more times to free up some space before the allocation is performed.
danielk197752622822006-01-09 09:59:49 +00004014**
mihailimdc884822008-06-22 08:58:50 +00004015** The limit is called "soft", because if [sqlite3_release_memory()]
4016** cannot free sufficient memory to prevent the limit from being exceeded,
drhe30f4422007-08-21 16:15:55 +00004017** the memory is allocated anyway and the current operation proceeds.
drh6ed48bf2007-06-14 20:57:18 +00004018**
4019** A negative or zero value for N means that there is no soft heap limit and
drhe30f4422007-08-21 16:15:55 +00004020** [sqlite3_release_memory()] will only be called when memory is exhausted.
drhafc91042008-02-21 02:09:45 +00004021** The default value for the soft heap limit is zero.
drh6ed48bf2007-06-14 20:57:18 +00004022**
mihailim15194222008-06-22 09:55:14 +00004023** SQLite makes a best effort to honor the soft heap limit.
shane26b34032008-05-23 17:21:09 +00004024** But if the soft heap limit cannot be honored, execution will
mihailimdc884822008-06-22 08:58:50 +00004025** continue without error or notification. This is why the limit is
drh6ed48bf2007-06-14 20:57:18 +00004026** called a "soft" limit. It is advisory only.
4027**
drhe30f4422007-08-21 16:15:55 +00004028** Prior to SQLite version 3.5.0, this routine only constrained the memory
4029** allocated by a single thread - the same thread in which this routine
4030** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
drhafc91042008-02-21 02:09:45 +00004031** applied to all threads. The value specified for the soft heap limit
4032** is an upper bound on the total memory allocation for all threads. In
drh8bacf972007-08-25 16:21:29 +00004033** version 3.5.0 there is no mechanism for limiting the heap usage for
4034** individual threads.
drhafc91042008-02-21 02:09:45 +00004035**
drh8b39db12009-02-18 18:37:58 +00004036** Requirements:
4037** [H16351] [H16352] [H16353] [H16354] [H16355] [H16358]
danielk197752622822006-01-09 09:59:49 +00004038*/
drhd2d4a6b2006-01-10 15:18:27 +00004039void sqlite3_soft_heap_limit(int);
danielk197752622822006-01-09 09:59:49 +00004040
4041/*
drh9cd29642008-07-23 00:52:55 +00004042** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
drh6ed48bf2007-06-14 20:57:18 +00004043**
mihailimdc884822008-06-22 08:58:50 +00004044** This routine returns metadata about a specific column of a specific
4045** database table accessible using the [database connection] handle
4046** passed as the first function argument.
danielk1977deb802c2006-02-09 13:43:28 +00004047**
mihailimdc884822008-06-22 08:58:50 +00004048** The column is identified by the second, third and fourth parameters to
danielk1977deb802c2006-02-09 13:43:28 +00004049** this function. The second parameter is either the name of the database
4050** (i.e. "main", "temp" or an attached database) containing the specified
4051** table or NULL. If it is NULL, then all attached databases are searched
mihailimdc884822008-06-22 08:58:50 +00004052** for the table using the same algorithm used by the database engine to
danielk1977deb802c2006-02-09 13:43:28 +00004053** resolve unqualified table references.
4054**
mihailimdc884822008-06-22 08:58:50 +00004055** The third and fourth parameters to this function are the table and column
4056** name of the desired column, respectively. Neither of these parameters
danielk1977deb802c2006-02-09 13:43:28 +00004057** may be NULL.
4058**
mihailimdc884822008-06-22 08:58:50 +00004059** Metadata is returned by writing to the memory locations passed as the 5th
4060** and subsequent parameters to this function. Any of these arguments may be
4061** NULL, in which case the corresponding element of metadata is omitted.
mihailim15194222008-06-22 09:55:14 +00004062**
mihailimdc884822008-06-22 08:58:50 +00004063** <blockquote>
4064** <table border="1">
4065** <tr><th> Parameter <th> Output<br>Type <th> Description
danielk1977deb802c2006-02-09 13:43:28 +00004066**
mihailimdc884822008-06-22 08:58:50 +00004067** <tr><td> 5th <td> const char* <td> Data type
4068** <tr><td> 6th <td> const char* <td> Name of default collation sequence
4069** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
4070** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
drh49c3d572008-12-15 22:51:38 +00004071** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
mihailimdc884822008-06-22 08:58:50 +00004072** </table>
4073** </blockquote>
danielk1977deb802c2006-02-09 13:43:28 +00004074**
mihailimdc884822008-06-22 08:58:50 +00004075** The memory pointed to by the character pointers returned for the
4076** declaration type and collation sequence is valid only until the next
4077** call to any SQLite API function.
danielk1977deb802c2006-02-09 13:43:28 +00004078**
mihailimdc884822008-06-22 08:58:50 +00004079** If the specified table is actually a view, an [error code] is returned.
danielk1977deb802c2006-02-09 13:43:28 +00004080**
mihailimdc884822008-06-22 08:58:50 +00004081** If the specified column is "rowid", "oid" or "_rowid_" and an
drh49c3d572008-12-15 22:51:38 +00004082** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
danielk1977deb802c2006-02-09 13:43:28 +00004083** parameters are set for the explicitly declared column. If there is no
drh49c3d572008-12-15 22:51:38 +00004084** explicitly declared [INTEGER PRIMARY KEY] column, then the output
mihailimdc884822008-06-22 08:58:50 +00004085** parameters are set as follows:
danielk1977deb802c2006-02-09 13:43:28 +00004086**
drh6ed48bf2007-06-14 20:57:18 +00004087** <pre>
danielk1977deb802c2006-02-09 13:43:28 +00004088** data type: "INTEGER"
4089** collation sequence: "BINARY"
4090** not null: 0
4091** primary key: 1
4092** auto increment: 0
drh6ed48bf2007-06-14 20:57:18 +00004093** </pre>
danielk1977deb802c2006-02-09 13:43:28 +00004094**
4095** This function may load one or more schemas from database files. If an
4096** error occurs during this process, or if the requested table or column
mihailimdc884822008-06-22 08:58:50 +00004097** cannot be found, an [error code] is returned and an error message left
4098** in the [database connection] (to be retrieved using sqlite3_errmsg()).
danielk19774b1ae992006-02-10 03:06:10 +00004099**
4100** This API is only available if the library was compiled with the
drh4ead1482008-06-26 18:16:05 +00004101** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
danielk1977deb802c2006-02-09 13:43:28 +00004102*/
4103int sqlite3_table_column_metadata(
4104 sqlite3 *db, /* Connection handle */
4105 const char *zDbName, /* Database name or NULL */
4106 const char *zTableName, /* Table name */
4107 const char *zColumnName, /* Column name */
4108 char const **pzDataType, /* OUTPUT: Declared data type */
4109 char const **pzCollSeq, /* OUTPUT: Collation sequence name */
4110 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
4111 int *pPrimaryKey, /* OUTPUT: True if column part of PK */
drh98c94802007-10-01 13:50:31 +00004112 int *pAutoinc /* OUTPUT: True if column is auto-increment */
danielk1977deb802c2006-02-09 13:43:28 +00004113);
4114
4115/*
drh9cd29642008-07-23 00:52:55 +00004116** CAPI3REF: Load An Extension {H12600} <S20500>
drh1e397f82006-06-08 15:28:43 +00004117**
mihailimdc884822008-06-22 08:58:50 +00004118** This interface loads an SQLite extension library from the named file.
drh1e397f82006-06-08 15:28:43 +00004119**
drh9a247912008-07-22 18:45:08 +00004120** {H12601} The sqlite3_load_extension() interface attempts to load an
mihailimdc884822008-06-22 08:58:50 +00004121** SQLite extension library contained in the file zFile.
drh1e397f82006-06-08 15:28:43 +00004122**
drh9a247912008-07-22 18:45:08 +00004123** {H12602} The entry point is zProc.
mihailimdc884822008-06-22 08:58:50 +00004124**
drh9a247912008-07-22 18:45:08 +00004125** {H12603} zProc may be 0, in which case the name of the entry point
mihailimdc884822008-06-22 08:58:50 +00004126** defaults to "sqlite3_extension_init".
4127**
drh9a247912008-07-22 18:45:08 +00004128** {H12604} The sqlite3_load_extension() interface shall return
mihailimdc884822008-06-22 08:58:50 +00004129** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
4130**
drh9a247912008-07-22 18:45:08 +00004131** {H12605} If an error occurs and pzErrMsg is not 0, then the
mihailim421dfca2008-06-22 16:35:48 +00004132** [sqlite3_load_extension()] interface shall attempt to
4133** fill *pzErrMsg with error message text stored in memory
4134** obtained from [sqlite3_malloc()]. {END} The calling function
4135** should free this memory by calling [sqlite3_free()].
4136**
drh9a247912008-07-22 18:45:08 +00004137** {H12606} Extension loading must be enabled using
mihailimdc884822008-06-22 08:58:50 +00004138** [sqlite3_enable_load_extension()] prior to calling this API,
4139** otherwise an error will be returned.
drh1e397f82006-06-08 15:28:43 +00004140*/
4141int sqlite3_load_extension(
4142 sqlite3 *db, /* Load the extension into this database connection */
4143 const char *zFile, /* Name of the shared library containing extension */
4144 const char *zProc, /* Entry point. Derived from zFile if 0 */
4145 char **pzErrMsg /* Put error message here if not 0 */
4146);
4147
4148/*
drh9cd29642008-07-23 00:52:55 +00004149** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500>
drh6ed48bf2007-06-14 20:57:18 +00004150**
drhc2e87a32006-06-27 15:16:14 +00004151** So as not to open security holes in older applications that are
drh6ed48bf2007-06-14 20:57:18 +00004152** unprepared to deal with extension loading, and as a means of disabling
mihailimdc884822008-06-22 08:58:50 +00004153** extension loading while evaluating user-entered SQL, the following API
4154** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
drhc2e87a32006-06-27 15:16:14 +00004155**
mihailimdc884822008-06-22 08:58:50 +00004156** Extension loading is off by default. See ticket #1863.
4157**
drh9a247912008-07-22 18:45:08 +00004158** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
mihailimdc884822008-06-22 08:58:50 +00004159** to turn extension loading on and call it with onoff==0 to turn
4160** it back off again.
4161**
drh9a247912008-07-22 18:45:08 +00004162** {H12622} Extension loading is off by default.
drhc2e87a32006-06-27 15:16:14 +00004163*/
4164int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
4165
4166/*
drh9cd29642008-07-23 00:52:55 +00004167** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
drh9eff6162006-06-12 21:59:13 +00004168**
drh1409be62006-08-23 20:07:20 +00004169** This API can be invoked at program startup in order to register
4170** one or more statically linked extensions that will be available
mihailim04bcc002008-06-22 10:21:27 +00004171** to all new [database connections]. {END}
mihailimdc884822008-06-22 08:58:50 +00004172**
4173** This routine stores a pointer to the extension in an array that is
4174** obtained from [sqlite3_malloc()]. If you run a memory leak checker
4175** on your program and it reports a leak because of this array, invoke
4176** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
4177**
drh9a247912008-07-22 18:45:08 +00004178** {H12641} This function registers an extension entry point that is
mihailimdc884822008-06-22 08:58:50 +00004179** automatically invoked whenever a new [database connection]
4180** is opened using [sqlite3_open()], [sqlite3_open16()],
4181** or [sqlite3_open_v2()].
4182**
drh9a247912008-07-22 18:45:08 +00004183** {H12642} Duplicate extensions are detected so calling this routine
mihailimdc884822008-06-22 08:58:50 +00004184** multiple times with the same extension is harmless.
4185**
drh9a247912008-07-22 18:45:08 +00004186** {H12643} This routine stores a pointer to the extension in an array
mihailimdc884822008-06-22 08:58:50 +00004187** that is obtained from [sqlite3_malloc()].
4188**
drh9a247912008-07-22 18:45:08 +00004189** {H12644} Automatic extensions apply across all threads.
drh1409be62006-08-23 20:07:20 +00004190*/
drh1875f7a2008-12-08 18:19:17 +00004191int sqlite3_auto_extension(void (*xEntryPoint)(void));
drh1409be62006-08-23 20:07:20 +00004192
drh1409be62006-08-23 20:07:20 +00004193/*
drh9cd29642008-07-23 00:52:55 +00004194** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
drh1409be62006-08-23 20:07:20 +00004195**
mihailim04bcc002008-06-22 10:21:27 +00004196** This function disables all previously registered automatic
4197** extensions. {END} It undoes the effect of all prior
4198** [sqlite3_auto_extension()] calls.
drh6ed48bf2007-06-14 20:57:18 +00004199**
drh9a247912008-07-22 18:45:08 +00004200** {H12661} This function disables all previously registered
mihailimdc884822008-06-22 08:58:50 +00004201** automatic extensions.
4202**
drh9a247912008-07-22 18:45:08 +00004203** {H12662} This function disables automatic extensions in all threads.
drh1409be62006-08-23 20:07:20 +00004204*/
4205void sqlite3_reset_auto_extension(void);
4206
drh1409be62006-08-23 20:07:20 +00004207/*
4208****** EXPERIMENTAL - subject to change without notice **************
4209**
drh9eff6162006-06-12 21:59:13 +00004210** The interface to the virtual-table mechanism is currently considered
4211** to be experimental. The interface might change in incompatible ways.
4212** If this is a problem for you, do not use the interface at this time.
4213**
shane26b34032008-05-23 17:21:09 +00004214** When the virtual-table mechanism stabilizes, we will declare the
drh9eff6162006-06-12 21:59:13 +00004215** interface fixed, support it indefinitely, and remove this comment.
4216*/
4217
4218/*
4219** Structures used by the virtual table interface
drhe09daa92006-06-10 13:29:31 +00004220*/
4221typedef struct sqlite3_vtab sqlite3_vtab;
4222typedef struct sqlite3_index_info sqlite3_index_info;
4223typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
4224typedef struct sqlite3_module sqlite3_module;
drh9eff6162006-06-12 21:59:13 +00004225
4226/*
drh9cd29642008-07-23 00:52:55 +00004227** CAPI3REF: Virtual Table Object {H18000} <S20400>
drh9cff9dc2009-04-13 14:43:40 +00004228** KEYWORDS: sqlite3_module {virtual table module}
drhd5a68d32008-08-04 13:44:57 +00004229** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004230**
drh9cff9dc2009-04-13 14:43:40 +00004231** This structure, sometimes called a a "virtual table module",
4232** defines the implementation of a [virtual tables].
4233** This structure consists mostly of methods for the module.
mihailim15194222008-06-22 09:55:14 +00004234**
drh9cff9dc2009-04-13 14:43:40 +00004235** A virtual table module is created by filling in a persistent
4236** instance of this structure and passing a pointer to that instance
4237** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
4238** The registration remains valid until it is replaced by a different
4239** module or until the [database connection] closes. The content
4240** of this structure must not change while it is registered with
4241** any database connection.
drh9eff6162006-06-12 21:59:13 +00004242*/
drhe09daa92006-06-10 13:29:31 +00004243struct sqlite3_module {
4244 int iVersion;
danielk19779da9d472006-06-14 06:58:15 +00004245 int (*xCreate)(sqlite3*, void *pAux,
drhe4102962006-09-11 00:34:22 +00004246 int argc, const char *const*argv,
drh4ca8aac2006-09-10 17:31:58 +00004247 sqlite3_vtab **ppVTab, char**);
danielk19779da9d472006-06-14 06:58:15 +00004248 int (*xConnect)(sqlite3*, void *pAux,
drhe4102962006-09-11 00:34:22 +00004249 int argc, const char *const*argv,
drh4ca8aac2006-09-10 17:31:58 +00004250 sqlite3_vtab **ppVTab, char**);
drhe09daa92006-06-10 13:29:31 +00004251 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
4252 int (*xDisconnect)(sqlite3_vtab *pVTab);
4253 int (*xDestroy)(sqlite3_vtab *pVTab);
4254 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
4255 int (*xClose)(sqlite3_vtab_cursor*);
drh4be8b512006-06-13 23:51:34 +00004256 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
drhe09daa92006-06-10 13:29:31 +00004257 int argc, sqlite3_value **argv);
4258 int (*xNext)(sqlite3_vtab_cursor*);
danielk1977a298e902006-06-22 09:53:48 +00004259 int (*xEof)(sqlite3_vtab_cursor*);
drhe09daa92006-06-10 13:29:31 +00004260 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
drh6d2069d2007-08-14 01:58:53 +00004261 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
4262 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
drhe09daa92006-06-10 13:29:31 +00004263 int (*xBegin)(sqlite3_vtab *pVTab);
4264 int (*xSync)(sqlite3_vtab *pVTab);
4265 int (*xCommit)(sqlite3_vtab *pVTab);
4266 int (*xRollback)(sqlite3_vtab *pVTab);
drhb7f6f682006-07-08 17:06:43 +00004267 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
drhe94b0c32006-07-08 18:09:15 +00004268 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
4269 void **ppArg);
danielk1977182c4ba2007-06-27 15:53:34 +00004270 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
drhe09daa92006-06-10 13:29:31 +00004271};
drh9eff6162006-06-12 21:59:13 +00004272
4273/*
drh9cd29642008-07-23 00:52:55 +00004274** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
drhb4d58ae2008-02-21 20:17:06 +00004275** KEYWORDS: sqlite3_index_info
drhd5a68d32008-08-04 13:44:57 +00004276** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004277**
drh9eff6162006-06-12 21:59:13 +00004278** The sqlite3_index_info structure and its substructures is used to
drh9cff9dc2009-04-13 14:43:40 +00004279** pass information into and receive the reply from the [xBestIndex]
4280** method of a [virtual table module]. The fields under **Inputs** are the
drh9eff6162006-06-12 21:59:13 +00004281** inputs to xBestIndex and are read-only. xBestIndex inserts its
4282** results into the **Outputs** fields.
4283**
mihailim15194222008-06-22 09:55:14 +00004284** The aConstraint[] array records WHERE clause constraints of the form:
drh9eff6162006-06-12 21:59:13 +00004285**
mihailim15194222008-06-22 09:55:14 +00004286** <pre>column OP expr</pre>
drh9eff6162006-06-12 21:59:13 +00004287**
mihailim15194222008-06-22 09:55:14 +00004288** where OP is =, &lt;, &lt;=, &gt;, or &gt;=. The particular operator is
4289** stored in aConstraint[].op. The index of the column is stored in
drh9eff6162006-06-12 21:59:13 +00004290** aConstraint[].iColumn. aConstraint[].usable is TRUE if the
4291** expr on the right-hand side can be evaluated (and thus the constraint
4292** is usable) and false if it cannot.
4293**
4294** The optimizer automatically inverts terms of the form "expr OP column"
drh98c94802007-10-01 13:50:31 +00004295** and makes other simplifications to the WHERE clause in an attempt to
drh9eff6162006-06-12 21:59:13 +00004296** get as many WHERE clause terms into the form shown above as possible.
4297** The aConstraint[] array only reports WHERE clause terms in the correct
4298** form that refer to the particular virtual table being queried.
4299**
4300** Information about the ORDER BY clause is stored in aOrderBy[].
4301** Each term of aOrderBy records a column of the ORDER BY clause.
4302**
drh9cff9dc2009-04-13 14:43:40 +00004303** The [xBestIndex] method must fill aConstraintUsage[] with information
danielk19775fac9f82006-06-13 14:16:58 +00004304** about what parameters to pass to xFilter. If argvIndex>0 then
drh9eff6162006-06-12 21:59:13 +00004305** the right-hand side of the corresponding aConstraint[] is evaluated
4306** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit
4307** is true, then the constraint is assumed to be fully handled by the
4308** virtual table and is not checked again by SQLite.
4309**
drh9cff9dc2009-04-13 14:43:40 +00004310** The idxNum and idxPtr values are recorded and passed into the
4311** [xFilter] method.
4312** [sqlite3_free()] is used to free idxPtr if and only iff
4313** needToFreeIdxPtr is true.
drh9eff6162006-06-12 21:59:13 +00004314**
drh9cff9dc2009-04-13 14:43:40 +00004315** The orderByConsumed means that output from [xFilter]/[xNext] will occur in
drh9eff6162006-06-12 21:59:13 +00004316** the correct order to satisfy the ORDER BY clause so that no separate
4317** sorting step is required.
4318**
4319** The estimatedCost value is an estimate of the cost of doing the
4320** particular lookup. A full scan of a table with N entries should have
4321** a cost of N. A binary search of a table of N entries should have a
4322** cost of approximately log(N).
4323*/
drhe09daa92006-06-10 13:29:31 +00004324struct sqlite3_index_info {
4325 /* Inputs */
drh6cca08c2007-09-21 12:43:16 +00004326 int nConstraint; /* Number of entries in aConstraint */
4327 struct sqlite3_index_constraint {
drh9eff6162006-06-12 21:59:13 +00004328 int iColumn; /* Column on left-hand side of constraint */
4329 unsigned char op; /* Constraint operator */
4330 unsigned char usable; /* True if this constraint is usable */
4331 int iTermOffset; /* Used internally - xBestIndex should ignore */
drh6cca08c2007-09-21 12:43:16 +00004332 } *aConstraint; /* Table of WHERE clause constraints */
4333 int nOrderBy; /* Number of terms in the ORDER BY clause */
4334 struct sqlite3_index_orderby {
drh9eff6162006-06-12 21:59:13 +00004335 int iColumn; /* Column number */
4336 unsigned char desc; /* True for DESC. False for ASC. */
drh6cca08c2007-09-21 12:43:16 +00004337 } *aOrderBy; /* The ORDER BY clause */
drhe09daa92006-06-10 13:29:31 +00004338 /* Outputs */
drh9eff6162006-06-12 21:59:13 +00004339 struct sqlite3_index_constraint_usage {
4340 int argvIndex; /* if >0, constraint is part of argv to xFilter */
4341 unsigned char omit; /* Do not code a test for this constraint */
drh6cca08c2007-09-21 12:43:16 +00004342 } *aConstraintUsage;
drh4be8b512006-06-13 23:51:34 +00004343 int idxNum; /* Number used to identify the index */
4344 char *idxStr; /* String, possibly obtained from sqlite3_malloc */
4345 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
drh9eff6162006-06-12 21:59:13 +00004346 int orderByConsumed; /* True if output is already ordered */
4347 double estimatedCost; /* Estimated cost of using this index */
drhe09daa92006-06-10 13:29:31 +00004348};
drh9eff6162006-06-12 21:59:13 +00004349#define SQLITE_INDEX_CONSTRAINT_EQ 2
4350#define SQLITE_INDEX_CONSTRAINT_GT 4
4351#define SQLITE_INDEX_CONSTRAINT_LE 8
4352#define SQLITE_INDEX_CONSTRAINT_LT 16
4353#define SQLITE_INDEX_CONSTRAINT_GE 32
4354#define SQLITE_INDEX_CONSTRAINT_MATCH 64
4355
4356/*
drh9cd29642008-07-23 00:52:55 +00004357** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400>
drhd5a68d32008-08-04 13:44:57 +00004358** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004359**
drh9cff9dc2009-04-13 14:43:40 +00004360** This routine is used to register a new [virtual table module] name.
4361** Module names must be registered before
4362** creating a new [virtual table] using the module, or before using a
4363** preexisting [virtual table] for the module.
mihailim15194222008-06-22 09:55:14 +00004364**
drh9cff9dc2009-04-13 14:43:40 +00004365** The module name is registered on the [database connection] specified
4366** by the first parameter. The name of the module is given by the
4367** second parameter. The third parameter is a pointer to
4368** the implementation of the [virtual table module]. The fourth
4369** parameter is an arbitrary client data pointer that is passed through
4370** into the [xCreate] and [xConnect] methods of the virtual table module
4371** when a new virtual table is be being created or reinitialized.
4372**
4373** This interface has exactly the same effect as calling
4374** [sqlite3_create_module_v2()] with a NULL client data destructor.
drh9eff6162006-06-12 21:59:13 +00004375*/
shanea79c3cc2008-08-11 17:27:01 +00004376SQLITE_EXPERIMENTAL int sqlite3_create_module(
drh9eff6162006-06-12 21:59:13 +00004377 sqlite3 *db, /* SQLite connection to register module with */
4378 const char *zName, /* Name of the module */
drh9cff9dc2009-04-13 14:43:40 +00004379 const sqlite3_module *p, /* Methods for the module */
4380 void *pClientData /* Client data for xCreate/xConnect */
drhb9bb7c12006-06-11 23:41:55 +00004381);
drhe09daa92006-06-10 13:29:31 +00004382
drh9eff6162006-06-12 21:59:13 +00004383/*
drh9cd29642008-07-23 00:52:55 +00004384** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
drhd5a68d32008-08-04 13:44:57 +00004385** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004386**
drh9cff9dc2009-04-13 14:43:40 +00004387** This routine is identical to the [sqlite3_create_module()] method,
4388** except that it has an extra parameter to specify
4389** a destructor function for the client data pointer. SQLite will
4390** invoke the destructor function (if it is not NULL) when SQLite
4391** no longer needs the pClientData pointer.
danielk1977832a58a2007-06-22 15:21:15 +00004392*/
shanea79c3cc2008-08-11 17:27:01 +00004393SQLITE_EXPERIMENTAL int sqlite3_create_module_v2(
danielk1977832a58a2007-06-22 15:21:15 +00004394 sqlite3 *db, /* SQLite connection to register module with */
4395 const char *zName, /* Name of the module */
drh9cff9dc2009-04-13 14:43:40 +00004396 const sqlite3_module *p, /* Methods for the module */
4397 void *pClientData, /* Client data for xCreate/xConnect */
danielk1977832a58a2007-06-22 15:21:15 +00004398 void(*xDestroy)(void*) /* Module destructor function */
4399);
4400
4401/*
drh9cd29642008-07-23 00:52:55 +00004402** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
drhb4d58ae2008-02-21 20:17:06 +00004403** KEYWORDS: sqlite3_vtab
drhd5a68d32008-08-04 13:44:57 +00004404** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004405**
drh9cff9dc2009-04-13 14:43:40 +00004406** Every [virtual table module] implementation uses a subclass
4407** of the following structure to describe a particular instance
4408** of the [virtual table]. Each subclass will
mihailim15194222008-06-22 09:55:14 +00004409** be tailored to the specific needs of the module implementation.
4410** The purpose of this superclass is to define certain fields that are
4411** common to all module implementations.
drhfe1368e2006-09-10 17:08:29 +00004412**
4413** Virtual tables methods can set an error message by assigning a
mihailim15194222008-06-22 09:55:14 +00004414** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
4415** take care that any prior string is freed by a call to [sqlite3_free()]
drhfe1368e2006-09-10 17:08:29 +00004416** prior to assigning a new string to zErrMsg. After the error message
4417** is delivered up to the client application, the string will be automatically
drh9cff9dc2009-04-13 14:43:40 +00004418** freed by sqlite3_free() and the zErrMsg field will be zeroed.
drh9eff6162006-06-12 21:59:13 +00004419*/
4420struct sqlite3_vtab {
drha967e882006-06-13 01:04:52 +00004421 const sqlite3_module *pModule; /* The module for this virtual table */
danielk1977595a5232009-07-24 17:58:53 +00004422 int nRef; /* NO LONGER USED */
drh4ca8aac2006-09-10 17:31:58 +00004423 char *zErrMsg; /* Error message from sqlite3_mprintf() */
drh9eff6162006-06-12 21:59:13 +00004424 /* Virtual table implementations will typically add additional fields */
4425};
4426
drhb4d58ae2008-02-21 20:17:06 +00004427/*
drh9cd29642008-07-23 00:52:55 +00004428** CAPI3REF: Virtual Table Cursor Object {H18020} <S20400>
drh9cff9dc2009-04-13 14:43:40 +00004429** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
drhd5a68d32008-08-04 13:44:57 +00004430** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004431**
drh9cff9dc2009-04-13 14:43:40 +00004432** Every [virtual table module] implementation uses a subclass of the
4433** following structure to describe cursors that point into the
4434** [virtual table] and are used
drh9eff6162006-06-12 21:59:13 +00004435** to loop through the virtual table. Cursors are created using the
drh9cff9dc2009-04-13 14:43:40 +00004436** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
4437** by the [sqlite3_module.xClose | xClose] method. Cussors are used
4438** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
4439** of the module. Each module implementation will define
drh9eff6162006-06-12 21:59:13 +00004440** the content of a cursor structure to suit its own needs.
4441**
4442** This superclass exists in order to define fields of the cursor that
4443** are common to all implementations.
4444*/
4445struct sqlite3_vtab_cursor {
4446 sqlite3_vtab *pVtab; /* Virtual table of this cursor */
4447 /* Virtual table implementations will typically add additional fields */
4448};
4449
4450/*
drh9cd29642008-07-23 00:52:55 +00004451** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400>
drhd5a68d32008-08-04 13:44:57 +00004452** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004453**
drh9cff9dc2009-04-13 14:43:40 +00004454** The [xCreate] and [xConnect] methods of a
4455** [virtual table module] call this interface
drh9eff6162006-06-12 21:59:13 +00004456** to declare the format (the names and datatypes of the columns) of
4457** the virtual tables they implement.
4458*/
drh9cff9dc2009-04-13 14:43:40 +00004459SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
drhe09daa92006-06-10 13:29:31 +00004460
4461/*
drh9cd29642008-07-23 00:52:55 +00004462** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
drhd5a68d32008-08-04 13:44:57 +00004463** EXPERIMENTAL
drhb4d58ae2008-02-21 20:17:06 +00004464**
drhb7481e72006-09-16 21:45:14 +00004465** Virtual tables can provide alternative implementations of functions
drh9cff9dc2009-04-13 14:43:40 +00004466** using the [xFindFunction] method of the [virtual table module].
4467** But global versions of those functions
drhb7481e72006-09-16 21:45:14 +00004468** must exist in order to be overloaded.
4469**
4470** This API makes sure a global version of a function with a particular
4471** name and number of parameters exists. If no such function exists
4472** before this API is called, a new function is created. The implementation
4473** of the new function always causes an exception to be thrown. So
4474** the new function is not good for anything by itself. Its only
shane26b34032008-05-23 17:21:09 +00004475** purpose is to be a placeholder function that can be overloaded
drh9cff9dc2009-04-13 14:43:40 +00004476** by a [virtual table].
drhb7481e72006-09-16 21:45:14 +00004477*/
shanea79c3cc2008-08-11 17:27:01 +00004478SQLITE_EXPERIMENTAL int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
drhb7481e72006-09-16 21:45:14 +00004479
4480/*
drh9eff6162006-06-12 21:59:13 +00004481** The interface to the virtual-table mechanism defined above (back up
4482** to a comment remarkably similar to this one) is currently considered
4483** to be experimental. The interface might change in incompatible ways.
4484** If this is a problem for you, do not use the interface at this time.
4485**
drh98c94802007-10-01 13:50:31 +00004486** When the virtual-table mechanism stabilizes, we will declare the
drh9eff6162006-06-12 21:59:13 +00004487** interface fixed, support it indefinitely, and remove this comment.
4488**
4489****** EXPERIMENTAL - subject to change without notice **************
4490*/
4491
danielk19778cbadb02007-05-03 16:31:26 +00004492/*
drh9cd29642008-07-23 00:52:55 +00004493** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
mihailim15194222008-06-22 09:55:14 +00004494** KEYWORDS: {BLOB handle} {BLOB handles}
drh6ed48bf2007-06-14 20:57:18 +00004495**
drhb4d58ae2008-02-21 20:17:06 +00004496** An instance of this object represents an open BLOB on which
mihailim1c492652008-06-21 18:02:16 +00004497** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
mihailim15194222008-06-22 09:55:14 +00004498** Objects of this type are created by [sqlite3_blob_open()]
4499** and destroyed by [sqlite3_blob_close()].
drh6ed48bf2007-06-14 20:57:18 +00004500** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
mihailim15194222008-06-22 09:55:14 +00004501** can be used to read or write small subsections of the BLOB.
4502** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
danielk19778cbadb02007-05-03 16:31:26 +00004503*/
danielk1977b4e9af92007-05-01 17:49:49 +00004504typedef struct sqlite3_blob sqlite3_blob;
4505
danielk19778cbadb02007-05-03 16:31:26 +00004506/*
drh9cd29642008-07-23 00:52:55 +00004507** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230>
drh6ed48bf2007-06-14 20:57:18 +00004508**
mihailim04bcc002008-06-22 10:21:27 +00004509** This interfaces opens a [BLOB handle | handle] to the BLOB located
drhf84ddc12008-03-24 12:51:46 +00004510** in row iRow, column zColumn, table zTable in database zDb;
mihailim15194222008-06-22 09:55:14 +00004511** in other words, the same BLOB that would be selected by:
danielk19778cbadb02007-05-03 16:31:26 +00004512**
drh6ed48bf2007-06-14 20:57:18 +00004513** <pre>
drh49c3d572008-12-15 22:51:38 +00004514** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
drhf5befa02007-12-06 02:42:07 +00004515** </pre> {END}
danielk19778cbadb02007-05-03 16:31:26 +00004516**
drh554b3832009-05-17 12:07:47 +00004517** If the flags parameter is non-zero, then the BLOB is opened for read
mihailim15194222008-06-22 09:55:14 +00004518** and write access. If it is zero, the BLOB is opened for read access.
danfedd4802009-10-07 11:29:40 +00004519** It is not possible to open a column that is part of an index or primary
4520** key for writing. ^If [foreign key constraints] are enabled, it is
drhc4ad1e92009-10-10 14:29:30 +00004521** not possible to open a column that is part of a [child key] for writing.
danielk19778cbadb02007-05-03 16:31:26 +00004522**
drhf84ddc12008-03-24 12:51:46 +00004523** Note that the database name is not the filename that contains
4524** the database but rather the symbolic name of the database that
4525** is assigned when the database is connected using [ATTACH].
mihailim15194222008-06-22 09:55:14 +00004526** For the main database file, the database name is "main".
4527** For TEMP tables, the database name is "temp".
drhf84ddc12008-03-24 12:51:46 +00004528**
mihailim15194222008-06-22 09:55:14 +00004529** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
drhabda6112009-05-14 22:37:47 +00004530** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
4531** to be a null pointer.
mihailim15194222008-06-22 09:55:14 +00004532** This function sets the [database connection] error code and message
drhabda6112009-05-14 22:37:47 +00004533** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
4534** functions. Note that the *ppBlob variable is always initialized in a
4535** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
4536** regardless of the success or failure of this routine.
mihailim15194222008-06-22 09:55:14 +00004537**
drh9de1b352008-06-26 15:04:57 +00004538** If the row that a BLOB handle points to is modified by an
4539** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
4540** then the BLOB handle is marked as "expired".
4541** This is true if any column of the row is changed, even a column
4542** other than the one the BLOB handle is open on.
4543** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
4544** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
4545** Changes written into a BLOB prior to the BLOB expiring are not
4546** rollback by the expiration of the BLOB. Such changes will eventually
4547** commit if the transaction continues to completion.
4548**
drhabda6112009-05-14 22:37:47 +00004549** Use the [sqlite3_blob_bytes()] interface to determine the size of
4550** the opened blob. The size of a blob may not be changed by this
drh9e42f8a2009-08-13 20:15:29 +00004551** interface. Use the [UPDATE] SQL command to change the size of a
drhabda6112009-05-14 22:37:47 +00004552** blob.
4553**
4554** The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
4555** and the built-in [zeroblob] SQL function can be used, if desired,
4556** to create an empty, zero-filled blob in which to read or write using
4557** this interface.
4558**
4559** To avoid a resource leak, every open [BLOB handle] should eventually
4560** be released by a call to [sqlite3_blob_close()].
4561**
drh8b39db12009-02-18 18:37:58 +00004562** Requirements:
4563** [H17813] [H17814] [H17816] [H17819] [H17821] [H17824]
danielk19778cbadb02007-05-03 16:31:26 +00004564*/
danielk1977b4e9af92007-05-01 17:49:49 +00004565int sqlite3_blob_open(
4566 sqlite3*,
4567 const char *zDb,
4568 const char *zTable,
4569 const char *zColumn,
drh6d2069d2007-08-14 01:58:53 +00004570 sqlite3_int64 iRow,
danielk1977b4e9af92007-05-01 17:49:49 +00004571 int flags,
4572 sqlite3_blob **ppBlob
4573);
4574
danielk19778cbadb02007-05-03 16:31:26 +00004575/*
drh9cd29642008-07-23 00:52:55 +00004576** CAPI3REF: Close A BLOB Handle {H17830} <S30230>
drh6ed48bf2007-06-14 20:57:18 +00004577**
mihailim15194222008-06-22 09:55:14 +00004578** Closes an open [BLOB handle].
drh2dd62be2007-12-04 13:22:43 +00004579**
drhb4d58ae2008-02-21 20:17:06 +00004580** Closing a BLOB shall cause the current transaction to commit
drhf5befa02007-12-06 02:42:07 +00004581** if there are no other BLOBs, no pending prepared statements, and the
mihailim15194222008-06-22 09:55:14 +00004582** database connection is in [autocommit mode].
drhb4d58ae2008-02-21 20:17:06 +00004583** If any writes were made to the BLOB, they might be held in cache
drhabda6112009-05-14 22:37:47 +00004584** until the close operation if they will fit.
mihailim15194222008-06-22 09:55:14 +00004585**
drhf5befa02007-12-06 02:42:07 +00004586** Closing the BLOB often forces the changes
drh2dd62be2007-12-04 13:22:43 +00004587** out to disk and so if any I/O errors occur, they will likely occur
drhabda6112009-05-14 22:37:47 +00004588** at the time when the BLOB is closed. Any errors that occur during
drh2dd62be2007-12-04 13:22:43 +00004589** closing are reported as a non-zero return value.
4590**
drhb4d58ae2008-02-21 20:17:06 +00004591** The BLOB is closed unconditionally. Even if this routine returns
drh2dd62be2007-12-04 13:22:43 +00004592** an error code, the BLOB is still closed.
drhb4d58ae2008-02-21 20:17:06 +00004593**
drhabda6112009-05-14 22:37:47 +00004594** Calling this routine with a null pointer (which as would be returned
4595** by failed call to [sqlite3_blob_open()]) is a harmless no-op.
4596**
drh8b39db12009-02-18 18:37:58 +00004597** Requirements:
4598** [H17833] [H17836] [H17839]
danielk19778cbadb02007-05-03 16:31:26 +00004599*/
danielk1977b4e9af92007-05-01 17:49:49 +00004600int sqlite3_blob_close(sqlite3_blob *);
4601
danielk19778cbadb02007-05-03 16:31:26 +00004602/*
drh9cd29642008-07-23 00:52:55 +00004603** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
drh6ed48bf2007-06-14 20:57:18 +00004604**
drhabda6112009-05-14 22:37:47 +00004605** Returns the size in bytes of the BLOB accessible via the
4606** successfully opened [BLOB handle] in its only argument. The
4607** incremental blob I/O routines can only read or overwriting existing
4608** blob content; they cannot change the size of a blob.
4609**
4610** This routine only works on a [BLOB handle] which has been created
4611** by a prior successful call to [sqlite3_blob_open()] and which has not
4612** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4613** to this routine results in undefined and probably undesirable behavior.
drhb4d58ae2008-02-21 20:17:06 +00004614**
drh8b39db12009-02-18 18:37:58 +00004615** Requirements:
4616** [H17843]
danielk19778cbadb02007-05-03 16:31:26 +00004617*/
danielk1977b4e9af92007-05-01 17:49:49 +00004618int sqlite3_blob_bytes(sqlite3_blob *);
4619
drh9eff6162006-06-12 21:59:13 +00004620/*
drh9cd29642008-07-23 00:52:55 +00004621** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
drh6ed48bf2007-06-14 20:57:18 +00004622**
mihailim15194222008-06-22 09:55:14 +00004623** This function is used to read data from an open [BLOB handle] into a
4624** caller-supplied buffer. N bytes of data are copied into buffer Z
4625** from the open BLOB, starting at offset iOffset.
danielk19778cbadb02007-05-03 16:31:26 +00004626**
mihailim15194222008-06-22 09:55:14 +00004627** If offset iOffset is less than N bytes from the end of the BLOB,
drhb4d58ae2008-02-21 20:17:06 +00004628** [SQLITE_ERROR] is returned and no data is read. If N or iOffset is
mihailim15194222008-06-22 09:55:14 +00004629** less than zero, [SQLITE_ERROR] is returned and no data is read.
drhabda6112009-05-14 22:37:47 +00004630** The size of the blob (and hence the maximum value of N+iOffset)
4631** can be determined using the [sqlite3_blob_bytes()] interface.
drhf5befa02007-12-06 02:42:07 +00004632**
drh9de1b352008-06-26 15:04:57 +00004633** An attempt to read from an expired [BLOB handle] fails with an
4634** error code of [SQLITE_ABORT].
4635**
mihailim15194222008-06-22 09:55:14 +00004636** On success, SQLITE_OK is returned.
4637** Otherwise, an [error code] or an [extended error code] is returned.
drhb4d58ae2008-02-21 20:17:06 +00004638**
drhabda6112009-05-14 22:37:47 +00004639** This routine only works on a [BLOB handle] which has been created
4640** by a prior successful call to [sqlite3_blob_open()] and which has not
4641** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4642** to this routine results in undefined and probably undesirable behavior.
4643**
4644** See also: [sqlite3_blob_write()].
4645**
drh8b39db12009-02-18 18:37:58 +00004646** Requirements:
4647** [H17853] [H17856] [H17859] [H17862] [H17863] [H17865] [H17868]
danielk19778cbadb02007-05-03 16:31:26 +00004648*/
drhb4d58ae2008-02-21 20:17:06 +00004649int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
danielk19778cbadb02007-05-03 16:31:26 +00004650
4651/*
drh9cd29642008-07-23 00:52:55 +00004652** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
drh6ed48bf2007-06-14 20:57:18 +00004653**
mihailim15194222008-06-22 09:55:14 +00004654** This function is used to write data into an open [BLOB handle] from a
4655** caller-supplied buffer. N bytes of data are copied from the buffer Z
4656** into the open BLOB, starting at offset iOffset.
danielk19778cbadb02007-05-03 16:31:26 +00004657**
mihailim15194222008-06-22 09:55:14 +00004658** If the [BLOB handle] passed as the first argument was not opened for
4659** writing (the flags parameter to [sqlite3_blob_open()] was zero),
4660** this function returns [SQLITE_READONLY].
danielk19778cbadb02007-05-03 16:31:26 +00004661**
mihailim15194222008-06-22 09:55:14 +00004662** This function may only modify the contents of the BLOB; it is
4663** not possible to increase the size of a BLOB using this API.
4664** If offset iOffset is less than N bytes from the end of the BLOB,
4665** [SQLITE_ERROR] is returned and no data is written. If N is
drhf5befa02007-12-06 02:42:07 +00004666** less than zero [SQLITE_ERROR] is returned and no data is written.
drhabda6112009-05-14 22:37:47 +00004667** The size of the BLOB (and hence the maximum value of N+iOffset)
4668** can be determined using the [sqlite3_blob_bytes()] interface.
danielk19778cbadb02007-05-03 16:31:26 +00004669**
drh9de1b352008-06-26 15:04:57 +00004670** An attempt to write to an expired [BLOB handle] fails with an
4671** error code of [SQLITE_ABORT]. Writes to the BLOB that occurred
4672** before the [BLOB handle] expired are not rolled back by the
4673** expiration of the handle, though of course those changes might
4674** have been overwritten by the statement that expired the BLOB handle
4675** or by other independent statements.
4676**
mihailim15194222008-06-22 09:55:14 +00004677** On success, SQLITE_OK is returned.
4678** Otherwise, an [error code] or an [extended error code] is returned.
drhb4d58ae2008-02-21 20:17:06 +00004679**
drhabda6112009-05-14 22:37:47 +00004680** This routine only works on a [BLOB handle] which has been created
4681** by a prior successful call to [sqlite3_blob_open()] and which has not
4682** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4683** to this routine results in undefined and probably undesirable behavior.
4684**
4685** See also: [sqlite3_blob_read()].
4686**
drh8b39db12009-02-18 18:37:58 +00004687** Requirements:
4688** [H17873] [H17874] [H17875] [H17876] [H17877] [H17879] [H17882] [H17885]
4689** [H17888]
danielk19778cbadb02007-05-03 16:31:26 +00004690*/
4691int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
4692
drhd84f9462007-08-15 11:28:56 +00004693/*
drh9cd29642008-07-23 00:52:55 +00004694** CAPI3REF: Virtual File System Objects {H11200} <S20100>
drhd84f9462007-08-15 11:28:56 +00004695**
4696** A virtual filesystem (VFS) is an [sqlite3_vfs] object
4697** that SQLite uses to interact
drhb4d58ae2008-02-21 20:17:06 +00004698** with the underlying operating system. Most SQLite builds come with a
drhd84f9462007-08-15 11:28:56 +00004699** single default VFS that is appropriate for the host computer.
4700** New VFSes can be registered and existing VFSes can be unregistered.
4701** The following interfaces are provided.
4702**
mihailim15194222008-06-22 09:55:14 +00004703** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
4704** Names are case sensitive.
drhb4d58ae2008-02-21 20:17:06 +00004705** Names are zero-terminated UTF-8 strings.
mihailim15194222008-06-22 09:55:14 +00004706** If there is no match, a NULL pointer is returned.
4707** If zVfsName is NULL then the default VFS is returned.
drhd84f9462007-08-15 11:28:56 +00004708**
drhb4d58ae2008-02-21 20:17:06 +00004709** New VFSes are registered with sqlite3_vfs_register().
4710** Each new VFS becomes the default VFS if the makeDflt flag is set.
4711** The same VFS can be registered multiple times without injury.
4712** To make an existing VFS into the default VFS, register it again
4713** with the makeDflt flag set. If two different VFSes with the
4714** same name are registered, the behavior is undefined. If a
drhb6f5cf32007-08-28 15:21:45 +00004715** VFS is registered with a name that is NULL or an empty string,
4716** then the behavior is undefined.
mihailim15194222008-06-22 09:55:14 +00004717**
drhb4d58ae2008-02-21 20:17:06 +00004718** Unregister a VFS with the sqlite3_vfs_unregister() interface.
4719** If the default VFS is unregistered, another VFS is chosen as
drhd84f9462007-08-15 11:28:56 +00004720** the default. The choice for the new VFS is arbitrary.
drhb4d58ae2008-02-21 20:17:06 +00004721**
drh8b39db12009-02-18 18:37:58 +00004722** Requirements:
4723** [H11203] [H11206] [H11209] [H11212] [H11215] [H11218]
drhd84f9462007-08-15 11:28:56 +00004724*/
drhd677b3d2007-08-20 22:48:41 +00004725sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
drhd677b3d2007-08-20 22:48:41 +00004726int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
4727int sqlite3_vfs_unregister(sqlite3_vfs*);
drhd84f9462007-08-15 11:28:56 +00004728
4729/*
drh9cd29642008-07-23 00:52:55 +00004730** CAPI3REF: Mutexes {H17000} <S20000>
drhd84f9462007-08-15 11:28:56 +00004731**
4732** The SQLite core uses these routines for thread
danielk19774a9d1f62008-06-19 08:51:23 +00004733** synchronization. Though they are intended for internal
drhd84f9462007-08-15 11:28:56 +00004734** use by SQLite, code that links against SQLite is
4735** permitted to use any of these routines.
4736**
mihailim15194222008-06-22 09:55:14 +00004737** The SQLite source code contains multiple implementations
drh8bacf972007-08-25 16:21:29 +00004738** of these mutex routines. An appropriate implementation
4739** is selected automatically at compile-time. The following
4740** implementations are available in the SQLite core:
drhd84f9462007-08-15 11:28:56 +00004741**
4742** <ul>
drhc7ce76a2007-08-30 14:10:30 +00004743** <li> SQLITE_MUTEX_OS2
drhd84f9462007-08-15 11:28:56 +00004744** <li> SQLITE_MUTEX_PTHREAD
drhc7ce76a2007-08-30 14:10:30 +00004745** <li> SQLITE_MUTEX_W32
drhd84f9462007-08-15 11:28:56 +00004746** <li> SQLITE_MUTEX_NOOP
drhd84f9462007-08-15 11:28:56 +00004747** </ul>
4748**
mihailim15194222008-06-22 09:55:14 +00004749** The SQLITE_MUTEX_NOOP implementation is a set of routines
4750** that does no real locking and is appropriate for use in
drhc7ce76a2007-08-30 14:10:30 +00004751** a single-threaded application. The SQLITE_MUTEX_OS2,
4752** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
shane26b34032008-05-23 17:21:09 +00004753** are appropriate for use on OS/2, Unix, and Windows.
mihailim15194222008-06-22 09:55:14 +00004754**
drh8bacf972007-08-25 16:21:29 +00004755** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
4756** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
danielk19774a9d1f62008-06-19 08:51:23 +00004757** implementation is included with the library. In this case the
4758** application must supply a custom mutex implementation using the
4759** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
mihailim15194222008-06-22 09:55:14 +00004760** before calling sqlite3_initialize() or any other public sqlite3_
danielk19774a9d1f62008-06-19 08:51:23 +00004761** function that calls sqlite3_initialize().
drhcb041342008-06-12 00:07:29 +00004762**
drh9a247912008-07-22 18:45:08 +00004763** {H17011} The sqlite3_mutex_alloc() routine allocates a new
4764** mutex and returns a pointer to it. {H17012} If it returns NULL
4765** that means that a mutex could not be allocated. {H17013} SQLite
4766** will unwind its stack and return an error. {H17014} The argument
drh6bdec4a2007-08-16 19:40:16 +00004767** to sqlite3_mutex_alloc() is one of these integer constants:
4768**
4769** <ul>
4770** <li> SQLITE_MUTEX_FAST
4771** <li> SQLITE_MUTEX_RECURSIVE
4772** <li> SQLITE_MUTEX_STATIC_MASTER
4773** <li> SQLITE_MUTEX_STATIC_MEM
drh86f8c192007-08-22 00:39:19 +00004774** <li> SQLITE_MUTEX_STATIC_MEM2
drh6bdec4a2007-08-16 19:40:16 +00004775** <li> SQLITE_MUTEX_STATIC_PRNG
danielk19779f61c2f2007-08-27 17:27:49 +00004776** <li> SQLITE_MUTEX_STATIC_LRU
danielk1977dfb316d2008-03-26 18:34:43 +00004777** <li> SQLITE_MUTEX_STATIC_LRU2
mihailim04bcc002008-06-22 10:21:27 +00004778** </ul>
drh6bdec4a2007-08-16 19:40:16 +00004779**
drh9a247912008-07-22 18:45:08 +00004780** {H17015} The first two constants cause sqlite3_mutex_alloc() to create
drh6bdec4a2007-08-16 19:40:16 +00004781** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
drhf5befa02007-12-06 02:42:07 +00004782** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END}
drh6bdec4a2007-08-16 19:40:16 +00004783** The mutex implementation does not need to make a distinction
4784** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
drh9a247912008-07-22 18:45:08 +00004785** not want to. {H17016} But SQLite will only request a recursive mutex in
drhf5befa02007-12-06 02:42:07 +00004786** cases where it really needs one. {END} If a faster non-recursive mutex
drh6bdec4a2007-08-16 19:40:16 +00004787** implementation is available on the host platform, the mutex subsystem
4788** might return such a mutex in response to SQLITE_MUTEX_FAST.
4789**
drh9a247912008-07-22 18:45:08 +00004790** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
shane7c7c3112009-08-17 15:31:23 +00004791** a pointer to a static preexisting mutex. {END} Six static mutexes are
drh6bdec4a2007-08-16 19:40:16 +00004792** used by the current version of SQLite. Future versions of SQLite
4793** may add additional static mutexes. Static mutexes are for internal
4794** use by SQLite only. Applications that use SQLite mutexes should
4795** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
4796** SQLITE_MUTEX_RECURSIVE.
4797**
drh9a247912008-07-22 18:45:08 +00004798** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
drh6bdec4a2007-08-16 19:40:16 +00004799** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
drh9a247912008-07-22 18:45:08 +00004800** returns a different mutex on every call. {H17034} But for the static
drh6bdec4a2007-08-16 19:40:16 +00004801** mutex types, the same mutex is returned on every call that has
mihailim04bcc002008-06-22 10:21:27 +00004802** the same type number.
drhd84f9462007-08-15 11:28:56 +00004803**
drh9a247912008-07-22 18:45:08 +00004804** {H17019} The sqlite3_mutex_free() routine deallocates a previously
4805** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
drh4766b292008-06-26 02:53:02 +00004806** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
4807** use when they are deallocated. {A17022} Attempting to deallocate a static
drh9a247912008-07-22 18:45:08 +00004808** mutex results in undefined behavior. {H17023} SQLite never deallocates
drhf5befa02007-12-06 02:42:07 +00004809** a static mutex. {END}
drhd84f9462007-08-15 11:28:56 +00004810**
drh6bdec4a2007-08-16 19:40:16 +00004811** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
drh9a247912008-07-22 18:45:08 +00004812** to enter a mutex. {H17024} If another thread is already within the mutex,
drh6bdec4a2007-08-16 19:40:16 +00004813** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
drh9a247912008-07-22 18:45:08 +00004814** SQLITE_BUSY. {H17025} The sqlite3_mutex_try() interface returns [SQLITE_OK]
4815** upon successful entry. {H17026} Mutexes created using
drhf5befa02007-12-06 02:42:07 +00004816** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
drh9a247912008-07-22 18:45:08 +00004817** {H17027} In such cases the,
drh6bdec4a2007-08-16 19:40:16 +00004818** mutex must be exited an equal number of times before another thread
drh4766b292008-06-26 02:53:02 +00004819** can enter. {A17028} If the same thread tries to enter any other
drhf5befa02007-12-06 02:42:07 +00004820** kind of mutex more than once, the behavior is undefined.
drh9a247912008-07-22 18:45:08 +00004821** {H17029} SQLite will never exhibit
drhcb041342008-06-12 00:07:29 +00004822** such behavior in its own use of mutexes.
drhd84f9462007-08-15 11:28:56 +00004823**
mihailim15194222008-06-22 09:55:14 +00004824** Some systems (for example, Windows 95) do not support the operation
4825** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
drh9a247912008-07-22 18:45:08 +00004826** will always return SQLITE_BUSY. {H17030} The SQLite core only ever uses
drhcb041342008-06-12 00:07:29 +00004827** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
drhca49cba2007-09-04 22:31:36 +00004828**
drh9a247912008-07-22 18:45:08 +00004829** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
drh4766b292008-06-26 02:53:02 +00004830** previously entered by the same thread. {A17032} The behavior
drh8bacf972007-08-25 16:21:29 +00004831** is undefined if the mutex is not currently entered by the
drh9a247912008-07-22 18:45:08 +00004832** calling thread or is not currently allocated. {H17033} SQLite will
drhf5befa02007-12-06 02:42:07 +00004833** never do either. {END}
drh8bacf972007-08-25 16:21:29 +00004834**
drh40257ff2008-06-13 18:24:27 +00004835** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
4836** sqlite3_mutex_leave() is a NULL pointer, then all three routines
4837** behave as no-ops.
4838**
drh8bacf972007-08-25 16:21:29 +00004839** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
4840*/
4841sqlite3_mutex *sqlite3_mutex_alloc(int);
4842void sqlite3_mutex_free(sqlite3_mutex*);
4843void sqlite3_mutex_enter(sqlite3_mutex*);
4844int sqlite3_mutex_try(sqlite3_mutex*);
4845void sqlite3_mutex_leave(sqlite3_mutex*);
4846
drh56a40a82008-06-18 13:47:03 +00004847/*
drh9cd29642008-07-23 00:52:55 +00004848** CAPI3REF: Mutex Methods Object {H17120} <S20130>
drhd5a68d32008-08-04 13:44:57 +00004849** EXPERIMENTAL
drh56a40a82008-06-18 13:47:03 +00004850**
4851** An instance of this structure defines the low-level routines
danielk19774a9d1f62008-06-19 08:51:23 +00004852** used to allocate and use mutexes.
4853**
4854** Usually, the default mutex implementations provided by SQLite are
mihailim15194222008-06-22 09:55:14 +00004855** sufficient, however the user has the option of substituting a custom
4856** implementation for specialized deployments or systems for which SQLite
danielk19774a9d1f62008-06-19 08:51:23 +00004857** does not provide a suitable implementation. In this case, the user
4858** creates and populates an instance of this structure to pass
mihailim15194222008-06-22 09:55:14 +00004859** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
danielk19774a9d1f62008-06-19 08:51:23 +00004860** Additionally, an instance of this structure can be used as an
4861** output variable when querying the system for the current mutex
4862** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
4863**
4864** The xMutexInit method defined by this structure is invoked as
4865** part of system initialization by the sqlite3_initialize() function.
drh9a247912008-07-22 18:45:08 +00004866** {H17001} The xMutexInit routine shall be called by SQLite once for each
mihailim15194222008-06-22 09:55:14 +00004867** effective call to [sqlite3_initialize()].
danielk19774a9d1f62008-06-19 08:51:23 +00004868**
4869** The xMutexEnd method defined by this structure is invoked as
4870** part of system shutdown by the sqlite3_shutdown() function. The
4871** implementation of this method is expected to release all outstanding
4872** resources obtained by the mutex methods implementation, especially
drh9a247912008-07-22 18:45:08 +00004873** those obtained by the xMutexInit method. {H17003} The xMutexEnd()
mihailim15194222008-06-22 09:55:14 +00004874** interface shall be invoked once for each call to [sqlite3_shutdown()].
danielk19774a9d1f62008-06-19 08:51:23 +00004875**
4876** The remaining seven methods defined by this structure (xMutexAlloc,
4877** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
4878** xMutexNotheld) implement the following interfaces (respectively):
drh56a40a82008-06-18 13:47:03 +00004879**
4880** <ul>
danielk19774a9d1f62008-06-19 08:51:23 +00004881** <li> [sqlite3_mutex_alloc()] </li>
4882** <li> [sqlite3_mutex_free()] </li>
4883** <li> [sqlite3_mutex_enter()] </li>
4884** <li> [sqlite3_mutex_try()] </li>
4885** <li> [sqlite3_mutex_leave()] </li>
4886** <li> [sqlite3_mutex_held()] </li>
4887** <li> [sqlite3_mutex_notheld()] </li>
drh56a40a82008-06-18 13:47:03 +00004888** </ul>
danielk19774a9d1f62008-06-19 08:51:23 +00004889**
4890** The only difference is that the public sqlite3_XXX functions enumerated
4891** above silently ignore any invocations that pass a NULL pointer instead
4892** of a valid mutex handle. The implementations of the methods defined
4893** by this structure are not required to handle this case, the results
4894** of passing a NULL pointer instead of a valid mutex handle are undefined
4895** (i.e. it is acceptable to provide an implementation that segfaults if
4896** it is passed a NULL pointer).
drh9ac06502009-08-17 13:42:29 +00004897**
4898** The xMutexInit() method must be threadsafe. It must be harmless to
4899** invoke xMutexInit() mutiple times within the same process and without
4900** intervening calls to xMutexEnd(). Second and subsequent calls to
4901** xMutexInit() must be no-ops.
4902**
4903** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
4904** and its associates). Similarly, xMutexAlloc() must not use SQLite memory
4905** allocation for a static mutex. However xMutexAlloc() may use SQLite
4906** memory allocation for a fast or recursive mutex.
4907**
4908** SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
4909** called, but only if the prior call to xMutexInit returned SQLITE_OK.
4910** If xMutexInit fails in any way, it is expected to clean up after itself
4911** prior to returning.
drh56a40a82008-06-18 13:47:03 +00004912*/
danielk19776d2ab0e2008-06-17 17:21:18 +00004913typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
4914struct sqlite3_mutex_methods {
4915 int (*xMutexInit)(void);
danielk19774a9d1f62008-06-19 08:51:23 +00004916 int (*xMutexEnd)(void);
danielk19776d2ab0e2008-06-17 17:21:18 +00004917 sqlite3_mutex *(*xMutexAlloc)(int);
4918 void (*xMutexFree)(sqlite3_mutex *);
4919 void (*xMutexEnter)(sqlite3_mutex *);
4920 int (*xMutexTry)(sqlite3_mutex *);
4921 void (*xMutexLeave)(sqlite3_mutex *);
danielk19776d2ab0e2008-06-17 17:21:18 +00004922 int (*xMutexHeld)(sqlite3_mutex *);
4923 int (*xMutexNotheld)(sqlite3_mutex *);
4924};
4925
drh8bacf972007-08-25 16:21:29 +00004926/*
drh9cd29642008-07-23 00:52:55 +00004927** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800>
drhd677b3d2007-08-20 22:48:41 +00004928**
4929** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
drh9a247912008-07-22 18:45:08 +00004930** are intended for use inside assert() statements. {H17081} The SQLite core
drhf77a2ff2007-08-25 14:49:36 +00004931** never uses these routines except inside an assert() and applications
drh9a247912008-07-22 18:45:08 +00004932** are advised to follow the lead of the core. {H17082} The core only
drh8bacf972007-08-25 16:21:29 +00004933** provides implementations for these routines when it is compiled
drh4766b292008-06-26 02:53:02 +00004934** with the SQLITE_DEBUG flag. {A17087} External mutex implementations
drh8bacf972007-08-25 16:21:29 +00004935** are only required to provide these routines if SQLITE_DEBUG is
4936** defined and if NDEBUG is not defined.
4937**
drh9a247912008-07-22 18:45:08 +00004938** {H17083} These routines should return true if the mutex in their argument
mihailim04bcc002008-06-22 10:21:27 +00004939** is held or not held, respectively, by the calling thread.
drh8bacf972007-08-25 16:21:29 +00004940**
drhfddfa2d2007-12-05 18:05:16 +00004941** {X17084} The implementation is not required to provided versions of these
mihailim04bcc002008-06-22 10:21:27 +00004942** routines that actually work. If the implementation does not provide working
4943** versions of these routines, it should at least provide stubs that always
4944** return true so that one does not get spurious assertion failures.
drhd677b3d2007-08-20 22:48:41 +00004945**
drh9a247912008-07-22 18:45:08 +00004946** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
drhfddfa2d2007-12-05 18:05:16 +00004947** the routine should return 1. {END} This seems counter-intuitive since
drhd677b3d2007-08-20 22:48:41 +00004948** clearly the mutex cannot be held if it does not exist. But the
4949** the reason the mutex does not exist is because the build is not
4950** using mutexes. And we do not want the assert() containing the
4951** call to sqlite3_mutex_held() to fail, so a non-zero return is
drh9a247912008-07-22 18:45:08 +00004952** the appropriate thing to do. {H17086} The sqlite3_mutex_notheld()
drhd677b3d2007-08-20 22:48:41 +00004953** interface should also return 1 when given a NULL pointer.
drhd84f9462007-08-15 11:28:56 +00004954*/
drhd677b3d2007-08-20 22:48:41 +00004955int sqlite3_mutex_held(sqlite3_mutex*);
4956int sqlite3_mutex_notheld(sqlite3_mutex*);
drh32bc3f62007-08-21 20:25:39 +00004957
4958/*
drh9cd29642008-07-23 00:52:55 +00004959** CAPI3REF: Mutex Types {H17001} <H17000>
drh32bc3f62007-08-21 20:25:39 +00004960**
drhd5a68d32008-08-04 13:44:57 +00004961** The [sqlite3_mutex_alloc()] interface takes a single argument
mihailim04bcc002008-06-22 10:21:27 +00004962** which is one of these integer constants.
drhd5a68d32008-08-04 13:44:57 +00004963**
4964** The set of static mutexes may change from one SQLite release to the
4965** next. Applications that override the built-in mutex logic must be
4966** prepared to accommodate additional static mutexes.
drh32bc3f62007-08-21 20:25:39 +00004967*/
drh6bdec4a2007-08-16 19:40:16 +00004968#define SQLITE_MUTEX_FAST 0
4969#define SQLITE_MUTEX_RECURSIVE 1
4970#define SQLITE_MUTEX_STATIC_MASTER 2
drh86f8c192007-08-22 00:39:19 +00004971#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
drh7555d8e2009-03-20 13:15:30 +00004972#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
4973#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
drh86f8c192007-08-22 00:39:19 +00004974#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
danielk19779f61c2f2007-08-27 17:27:49 +00004975#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
danielk1977dfb316d2008-03-26 18:34:43 +00004976#define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */
drh6d2069d2007-08-14 01:58:53 +00004977
drhcc6bb3e2007-08-31 16:11:35 +00004978/*
drh4413d0e2008-11-04 13:46:27 +00004979** CAPI3REF: Retrieve the mutex for a database connection {H17002} <H17000>
4980**
4981** This interface returns a pointer the [sqlite3_mutex] object that
4982** serializes access to the [database connection] given in the argument
4983** when the [threading mode] is Serialized.
4984** If the [threading mode] is Single-thread or Multi-thread then this
4985** routine returns a NULL pointer.
4986*/
4987sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
4988
4989/*
drh9cd29642008-07-23 00:52:55 +00004990** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
drhcc6bb3e2007-08-31 16:11:35 +00004991**
drh9a247912008-07-22 18:45:08 +00004992** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
drhcc6bb3e2007-08-31 16:11:35 +00004993** xFileControl method for the [sqlite3_io_methods] object associated
drh9a247912008-07-22 18:45:08 +00004994** with a particular database identified by the second argument. {H11302} The
drhcc6bb3e2007-08-31 16:11:35 +00004995** name of the database is the name assigned to the database by the
4996** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
drh9a247912008-07-22 18:45:08 +00004997** database. {H11303} To control the main database file, use the name "main"
4998** or a NULL pointer. {H11304} The third and fourth parameters to this routine
drhcc6bb3e2007-08-31 16:11:35 +00004999** are passed directly through to the second and third parameters of
drh9a247912008-07-22 18:45:08 +00005000** the xFileControl method. {H11305} The return value of the xFileControl
drhcc6bb3e2007-08-31 16:11:35 +00005001** method becomes the return value of this routine.
5002**
drh9a247912008-07-22 18:45:08 +00005003** {H11306} If the second parameter (zDbName) does not match the name of any
5004** open database file, then SQLITE_ERROR is returned. {H11307} This error
drhcc6bb3e2007-08-31 16:11:35 +00005005** code is not remembered and will not be recalled by [sqlite3_errcode()]
drh4766b292008-06-26 02:53:02 +00005006** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
5007** also return SQLITE_ERROR. {A11309} There is no way to distinguish between
drhcc6bb3e2007-08-31 16:11:35 +00005008** an incorrect zDbName and an SQLITE_ERROR return from the underlying
drhfddfa2d2007-12-05 18:05:16 +00005009** xFileControl method. {END}
drh4ff7fa02007-09-01 18:17:21 +00005010**
5011** See also: [SQLITE_FCNTL_LOCKSTATE]
drhcc6bb3e2007-08-31 16:11:35 +00005012*/
5013int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
drh6d2069d2007-08-14 01:58:53 +00005014
danielk19778cbadb02007-05-03 16:31:26 +00005015/*
drh9cd29642008-07-23 00:52:55 +00005016** CAPI3REF: Testing Interface {H11400} <S30800>
drhed13d982008-01-31 14:43:24 +00005017**
5018** The sqlite3_test_control() interface is used to read out internal
5019** state of SQLite and to inject faults into SQLite for testing
shane26b34032008-05-23 17:21:09 +00005020** purposes. The first parameter is an operation code that determines
drhed13d982008-01-31 14:43:24 +00005021** the number, meaning, and operation of all subsequent parameters.
5022**
5023** This interface is not for use by applications. It exists solely
5024** for verifying the correct operation of the SQLite library. Depending
5025** on how the SQLite library is compiled, this interface might not exist.
5026**
5027** The details of the operation codes, their meanings, the parameters
5028** they take, and what they do are all subject to change without notice.
5029** Unlike most of the SQLite API, this function is not guaranteed to
5030** operate consistently from one release to the next.
5031*/
5032int sqlite3_test_control(int op, ...);
5033
5034/*
drh9cd29642008-07-23 00:52:55 +00005035** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
drhed13d982008-01-31 14:43:24 +00005036**
5037** These constants are the valid operation code parameters used
5038** as the first argument to [sqlite3_test_control()].
5039**
shane26b34032008-05-23 17:21:09 +00005040** These parameters and their meanings are subject to change
drhed13d982008-01-31 14:43:24 +00005041** without notice. These values are for testing purposes only.
5042** Applications should not use any of these parameters or the
5043** [sqlite3_test_control()] interface.
5044*/
drh2fa18682008-03-19 14:15:34 +00005045#define SQLITE_TESTCTRL_PRNG_SAVE 5
5046#define SQLITE_TESTCTRL_PRNG_RESTORE 6
5047#define SQLITE_TESTCTRL_PRNG_RESET 7
drh3088d592008-03-21 16:45:47 +00005048#define SQLITE_TESTCTRL_BITVEC_TEST 8
danielk1977d09414c2008-06-19 18:17:49 +00005049#define SQLITE_TESTCTRL_FAULT_INSTALL 9
danielk19772d1d86f2008-06-20 14:59:51 +00005050#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
drhc7a3bb92009-02-05 16:31:45 +00005051#define SQLITE_TESTCTRL_PENDING_BYTE 11
drhf3af63f2009-05-09 18:59:42 +00005052#define SQLITE_TESTCTRL_ASSERT 12
5053#define SQLITE_TESTCTRL_ALWAYS 13
drhc046e3e2009-07-15 11:26:44 +00005054#define SQLITE_TESTCTRL_RESERVE 14
drhed13d982008-01-31 14:43:24 +00005055
drhf7141992008-06-19 00:16:08 +00005056/*
drh9cd29642008-07-23 00:52:55 +00005057** CAPI3REF: SQLite Runtime Status {H17200} <S60200>
drhd5a68d32008-08-04 13:44:57 +00005058** EXPERIMENTAL
drhf7141992008-06-19 00:16:08 +00005059**
mihailim15194222008-06-22 09:55:14 +00005060** This interface is used to retrieve runtime status information
drhf7141992008-06-19 00:16:08 +00005061** about the preformance of SQLite, and optionally to reset various
5062** highwater marks. The first argument is an integer code for
5063** the specific parameter to measure. Recognized integer codes
5064** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].
5065** The current value of the parameter is returned into *pCurrent.
5066** The highest recorded value is returned in *pHighwater. If the
5067** resetFlag is true, then the highest record value is reset after
5068** *pHighwater is written. Some parameters do not record the highest
5069** value. For those parameters
5070** nothing is written into *pHighwater and the resetFlag is ignored.
5071** Other parameters record only the highwater mark and not the current
5072** value. For these latter parameters nothing is written into *pCurrent.
5073**
5074** This routine returns SQLITE_OK on success and a non-zero
5075** [error code] on failure.
5076**
drh6aa5f152009-08-19 15:57:07 +00005077** This routine is threadsafe but is not atomic. This routine can be
drhf7141992008-06-19 00:16:08 +00005078** called while other threads are running the same or different SQLite
5079** interfaces. However the values returned in *pCurrent and
5080** *pHighwater reflect the status of SQLite at different points in time
5081** and it is possible that another thread might change the parameter
5082** in between the times when *pCurrent and *pHighwater are written.
5083**
drh2462e322008-07-31 14:47:54 +00005084** See also: [sqlite3_db_status()]
drhf7141992008-06-19 00:16:08 +00005085*/
shanea79c3cc2008-08-11 17:27:01 +00005086SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
drh2462e322008-07-31 14:47:54 +00005087
danielk1977075c23a2008-09-01 18:34:20 +00005088
drhf7141992008-06-19 00:16:08 +00005089/*
drh9cd29642008-07-23 00:52:55 +00005090** CAPI3REF: Status Parameters {H17250} <H17200>
drhd5a68d32008-08-04 13:44:57 +00005091** EXPERIMENTAL
drhf7141992008-06-19 00:16:08 +00005092**
5093** These integer constants designate various run-time status parameters
5094** that can be returned by [sqlite3_status()].
5095**
5096** <dl>
5097** <dt>SQLITE_STATUS_MEMORY_USED</dt>
5098** <dd>This parameter is the current amount of memory checked out
mihailim15194222008-06-22 09:55:14 +00005099** using [sqlite3_malloc()], either directly or indirectly. The
drhf7141992008-06-19 00:16:08 +00005100** figure includes calls made to [sqlite3_malloc()] by the application
5101** and internal memory usage by the SQLite library. Scratch memory
5102** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
5103** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
5104** this parameter. The amount returned is the sum of the allocation
mihailim15194222008-06-22 09:55:14 +00005105** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>
drhf7141992008-06-19 00:16:08 +00005106**
drhe50135e2008-08-05 17:53:22 +00005107** <dt>SQLITE_STATUS_MALLOC_SIZE</dt>
5108** <dd>This parameter records the largest memory allocation request
5109** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
5110** internal equivalents). Only the value returned in the
5111** *pHighwater parameter to [sqlite3_status()] is of interest.
5112** The value written into the *pCurrent parameter is undefined.</dd>
5113**
drhf7141992008-06-19 00:16:08 +00005114** <dt>SQLITE_STATUS_PAGECACHE_USED</dt>
5115** <dd>This parameter returns the number of pages used out of the
drhe50135e2008-08-05 17:53:22 +00005116** [pagecache memory allocator] that was configured using
5117** [SQLITE_CONFIG_PAGECACHE]. The
drhf7141992008-06-19 00:16:08 +00005118** value returned is in pages, not in bytes.</dd>
5119**
5120** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
5121** <dd>This parameter returns the number of bytes of page cache
5122** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
drhe50135e2008-08-05 17:53:22 +00005123** buffer and where forced to overflow to [sqlite3_malloc()]. The
5124** returned value includes allocations that overflowed because they
5125** where too large (they were larger than the "sz" parameter to
5126** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
5127** no space was left in the page cache.</dd>
5128**
5129** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
5130** <dd>This parameter records the largest memory allocation request
5131** handed to [pagecache memory allocator]. Only the value returned in the
5132** *pHighwater parameter to [sqlite3_status()] is of interest.
5133** The value written into the *pCurrent parameter is undefined.</dd>
drhf7141992008-06-19 00:16:08 +00005134**
5135** <dt>SQLITE_STATUS_SCRATCH_USED</dt>
5136** <dd>This parameter returns the number of allocations used out of the
drhe50135e2008-08-05 17:53:22 +00005137** [scratch memory allocator] configured using
drhf7141992008-06-19 00:16:08 +00005138** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
drhe50135e2008-08-05 17:53:22 +00005139** in bytes. Since a single thread may only have one scratch allocation
drhf7141992008-06-19 00:16:08 +00005140** outstanding at time, this parameter also reports the number of threads
5141** using scratch memory at the same time.</dd>
5142**
drh71f48622008-07-13 03:55:03 +00005143** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
drhf7141992008-06-19 00:16:08 +00005144** <dd>This parameter returns the number of bytes of scratch memory
5145** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
drhe50135e2008-08-05 17:53:22 +00005146** buffer and where forced to overflow to [sqlite3_malloc()]. The values
5147** returned include overflows because the requested allocation was too
5148** larger (that is, because the requested allocation was larger than the
5149** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
5150** slots were available.
5151** </dd>
drhf7141992008-06-19 00:16:08 +00005152**
drhe50135e2008-08-05 17:53:22 +00005153** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
drhf7141992008-06-19 00:16:08 +00005154** <dd>This parameter records the largest memory allocation request
drhe50135e2008-08-05 17:53:22 +00005155** handed to [scratch memory allocator]. Only the value returned in the
5156** *pHighwater parameter to [sqlite3_status()] is of interest.
5157** The value written into the *pCurrent parameter is undefined.</dd>
drhec424a52008-07-25 15:39:03 +00005158**
5159** <dt>SQLITE_STATUS_PARSER_STACK</dt>
5160** <dd>This parameter records the deepest parser stack. It is only
drh0a60a382008-07-31 17:16:05 +00005161** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>
drhf7141992008-06-19 00:16:08 +00005162** </dl>
5163**
5164** New status parameters may be added from time to time.
5165*/
5166#define SQLITE_STATUS_MEMORY_USED 0
5167#define SQLITE_STATUS_PAGECACHE_USED 1
5168#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
5169#define SQLITE_STATUS_SCRATCH_USED 3
5170#define SQLITE_STATUS_SCRATCH_OVERFLOW 4
5171#define SQLITE_STATUS_MALLOC_SIZE 5
drhec424a52008-07-25 15:39:03 +00005172#define SQLITE_STATUS_PARSER_STACK 6
drhe50135e2008-08-05 17:53:22 +00005173#define SQLITE_STATUS_PAGECACHE_SIZE 7
5174#define SQLITE_STATUS_SCRATCH_SIZE 8
drhf7141992008-06-19 00:16:08 +00005175
drh633e6d52008-07-28 19:34:53 +00005176/*
drhd1d38482008-10-07 23:46:38 +00005177** CAPI3REF: Database Connection Status {H17500} <S60200>
5178** EXPERIMENTAL
5179**
5180** This interface is used to retrieve runtime status information
5181** about a single [database connection]. The first argument is the
5182** database connection object to be interrogated. The second argument
5183** is the parameter to interrogate. Currently, the only allowed value
5184** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
5185** Additional options will likely appear in future releases of SQLite.
5186**
5187** The current value of the requested parameter is written into *pCur
5188** and the highest instantaneous value is written into *pHiwtr. If
5189** the resetFlg is true, then the highest instantaneous value is
5190** reset back down to the current value.
5191**
5192** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
5193*/
5194SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
5195
5196/*
5197** CAPI3REF: Status Parameters for database connections {H17520} <H17500>
drhd5a68d32008-08-04 13:44:57 +00005198** EXPERIMENTAL
drh633e6d52008-07-28 19:34:53 +00005199**
drh6aa5f152009-08-19 15:57:07 +00005200** These constants are the available integer "verbs" that can be passed as
5201** the second argument to the [sqlite3_db_status()] interface.
5202**
5203** New verbs may be added in future releases of SQLite. Existing verbs
5204** might be discontinued. Applications should check the return code from
5205** [sqlite3_db_status()] to make sure that the call worked.
5206** The [sqlite3_db_status()] interface will return a non-zero error code
5207** if a discontinued or unsupported verb is invoked.
drh633e6d52008-07-28 19:34:53 +00005208**
5209** <dl>
5210** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
5211** <dd>This parameter returns the number of lookaside memory slots currently
5212** checked out.</dd>
5213** </dl>
5214*/
5215#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
drhed13d982008-01-31 14:43:24 +00005216
drhd1d38482008-10-07 23:46:38 +00005217
5218/*
5219** CAPI3REF: Prepared Statement Status {H17550} <S60200>
5220** EXPERIMENTAL
5221**
5222** Each prepared statement maintains various
5223** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
5224** of times it has performed specific operations. These counters can
5225** be used to monitor the performance characteristics of the prepared
5226** statements. For example, if the number of table steps greatly exceeds
5227** the number of table searches or result rows, that would tend to indicate
5228** that the prepared statement is using a full table scan rather than
5229** an index.
5230**
5231** This interface is used to retrieve and reset counter values from
5232** a [prepared statement]. The first argument is the prepared statement
5233** object to be interrogated. The second argument
5234** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
5235** to be interrogated.
5236** The current value of the requested counter is returned.
5237** If the resetFlg is true, then the counter is reset to zero after this
5238** interface call returns.
5239**
5240** See also: [sqlite3_status()] and [sqlite3_db_status()].
5241*/
5242SQLITE_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
5243
5244/*
5245** CAPI3REF: Status Parameters for prepared statements {H17570} <H17550>
5246** EXPERIMENTAL
5247**
5248** These preprocessor macros define integer codes that name counter
5249** values associated with the [sqlite3_stmt_status()] interface.
5250** The meanings of the various counters are as follows:
5251**
5252** <dl>
5253** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
5254** <dd>This is the number of times that SQLite has stepped forward in
5255** a table as part of a full table scan. Large numbers for this counter
5256** may indicate opportunities for performance improvement through
5257** careful use of indices.</dd>
5258**
5259** <dt>SQLITE_STMTSTATUS_SORT</dt>
5260** <dd>This is the number of sort operations that have occurred.
5261** A non-zero value in this counter may indicate an opportunity to
5262** improvement performance through careful use of indices.</dd>
5263**
5264** </dl>
5265*/
5266#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
5267#define SQLITE_STMTSTATUS_SORT 2
5268
drhed13d982008-01-31 14:43:24 +00005269/*
drh21614742008-11-18 19:18:08 +00005270** CAPI3REF: Custom Page Cache Object
5271** EXPERIMENTAL
5272**
danielk1977bc2ca9e2008-11-13 14:28:28 +00005273** The sqlite3_pcache type is opaque. It is implemented by
5274** the pluggable module. The SQLite core has no knowledge of
5275** its size or internal structure and never deals with the
5276** sqlite3_pcache object except by holding and passing pointers
5277** to the object.
drh21614742008-11-18 19:18:08 +00005278**
5279** See [sqlite3_pcache_methods] for additional information.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005280*/
5281typedef struct sqlite3_pcache sqlite3_pcache;
5282
5283/*
drh21614742008-11-18 19:18:08 +00005284** CAPI3REF: Application Defined Page Cache.
drh67fba282009-08-26 00:26:51 +00005285** KEYWORDS: {page cache}
danielk1977bc2ca9e2008-11-13 14:28:28 +00005286** EXPERIMENTAL
5287**
drh21614742008-11-18 19:18:08 +00005288** The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
danielk1977bc2ca9e2008-11-13 14:28:28 +00005289** register an alternative page cache implementation by passing in an
5290** instance of the sqlite3_pcache_methods structure. The majority of the
shane7c7c3112009-08-17 15:31:23 +00005291** heap memory used by SQLite is used by the page cache to cache data read
danielk1977bc2ca9e2008-11-13 14:28:28 +00005292** from, or ready to be written to, the database file. By implementing a
5293** custom page cache using this API, an application can control more
shane7c7c3112009-08-17 15:31:23 +00005294** precisely the amount of memory consumed by SQLite, the way in which
drh67fba282009-08-26 00:26:51 +00005295** that memory is allocated and released, and the policies used to
danielk1977bc2ca9e2008-11-13 14:28:28 +00005296** determine exactly which parts of a database file are cached and for
5297** how long.
5298**
drh67fba282009-08-26 00:26:51 +00005299** The contents of the sqlite3_pcache_methods structure are copied to an
5300** internal buffer by SQLite within the call to [sqlite3_config]. Hence
5301** the application may discard the parameter after the call to
5302** [sqlite3_config()] returns.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005303**
drh21614742008-11-18 19:18:08 +00005304** The xInit() method is called once for each call to [sqlite3_initialize()]
danielk1977bc2ca9e2008-11-13 14:28:28 +00005305** (usually only once during the lifetime of the process). It is passed
5306** a copy of the sqlite3_pcache_methods.pArg value. It can be used to set
5307** up global structures and mutexes required by the custom page cache
shane7c7c3112009-08-17 15:31:23 +00005308** implementation.
5309**
5310** The xShutdown() method is called from within [sqlite3_shutdown()],
5311** if the application invokes this API. It can be used to clean up
5312** any outstanding resources before process shutdown, if required.
5313**
5314** SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
5315** the xInit method, so the xInit method need not be threadsafe. The
5316** xShutdown method is only called from [sqlite3_shutdown()] so it does
5317** not need to be threadsafe either. All other methods must be threadsafe
5318** in multithreaded applications.
5319**
5320** SQLite will never invoke xInit() more than once without an intervening
5321** call to xShutdown().
danielk1977bc2ca9e2008-11-13 14:28:28 +00005322**
drh67fba282009-08-26 00:26:51 +00005323** The xCreate() method is used to construct a new cache instance. SQLite
5324** will typically create one cache instance for each open database file,
5325** though this is not guaranteed. The
danielk1977bc2ca9e2008-11-13 14:28:28 +00005326** first parameter, szPage, is the size in bytes of the pages that must
drh67fba282009-08-26 00:26:51 +00005327** be allocated by the cache. szPage will not be a power of two. szPage
5328** will the page size of the database file that is to be cached plus an
5329** increment (here called "R") of about 100 or 200. SQLite will use the
5330** extra R bytes on each page to store metadata about the underlying
5331** database page on disk. The value of R depends
5332** on the SQLite version, the target platform, and how SQLite was compiled.
5333** R is constant for a particular build of SQLite. The second argument to
5334** xCreate(), bPurgeable, is true if the cache being created will
5335** be used to cache database pages of a file stored on disk, or
danielk1977bc2ca9e2008-11-13 14:28:28 +00005336** false if it is used for an in-memory database. The cache implementation
drh67fba282009-08-26 00:26:51 +00005337** does not have to do anything special based with the value of bPurgeable;
5338** it is purely advisory. On a cache where bPurgeable is false, SQLite will
5339** never invoke xUnpin() except to deliberately delete a page.
5340** In other words, a cache created with bPurgeable set to false will
5341** never contain any unpinned pages.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005342**
5343** The xCachesize() method may be called at any time by SQLite to set the
5344** suggested maximum cache-size (number of pages stored by) the cache
5345** instance passed as the first argument. This is the value configured using
drh21614742008-11-18 19:18:08 +00005346** the SQLite "[PRAGMA cache_size]" command. As with the bPurgeable parameter,
drh67fba282009-08-26 00:26:51 +00005347** the implementation is not required to do anything with this
5348** value; it is advisory only.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005349**
5350** The xPagecount() method should return the number of pages currently
drh67fba282009-08-26 00:26:51 +00005351** stored in the cache.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005352**
5353** The xFetch() method is used to fetch a page and return a pointer to it.
5354** A 'page', in this context, is a buffer of szPage bytes aligned at an
5355** 8-byte boundary. The page to be fetched is determined by the key. The
5356** mimimum key value is 1. After it has been retrieved using xFetch, the page
drh67fba282009-08-26 00:26:51 +00005357** is considered to be "pinned".
danielk1977bc2ca9e2008-11-13 14:28:28 +00005358**
drh67fba282009-08-26 00:26:51 +00005359** If the requested page is already in the page cache, then the page cache
5360** implementation must return a pointer to the page buffer with its content
5361** intact. If the requested page is not already in the cache, then the
5362** behavior of the cache implementation is determined by the value of the
5363** createFlag parameter passed to xFetch, according to the following table:
danielk1977bc2ca9e2008-11-13 14:28:28 +00005364**
5365** <table border=1 width=85% align=center>
drh67fba282009-08-26 00:26:51 +00005366** <tr><th> createFlag <th> Behaviour when page is not already in cache
5367** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
5368** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
5369** Otherwise return NULL.
5370** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
5371** NULL if allocating a new page is effectively impossible.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005372** </table>
5373**
drh67fba282009-08-26 00:26:51 +00005374** SQLite will normally invoke xFetch() with a createFlag of 0 or 1. If
5375** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
5376** attempt to unpin one or more cache pages by spilling the content of
5377** pinned pages to disk and synching the operating system disk cache. After
5378** attempting to unpin pages, the xFetch() method will be invoked again with
5379** a createFlag of 2.
5380**
danielk1977bc2ca9e2008-11-13 14:28:28 +00005381** xUnpin() is called by SQLite with a pointer to a currently pinned page
5382** as its second argument. If the third parameter, discard, is non-zero,
5383** then the page should be evicted from the cache. In this case SQLite
5384** assumes that the next time the page is retrieved from the cache using
5385** the xFetch() method, it will be zeroed. If the discard parameter is
5386** zero, then the page is considered to be unpinned. The cache implementation
drh67fba282009-08-26 00:26:51 +00005387** may choose to evict unpinned pages at any time.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005388**
5389** The cache is not required to perform any reference counting. A single
5390** call to xUnpin() unpins the page regardless of the number of prior calls
5391** to xFetch().
5392**
5393** The xRekey() method is used to change the key value associated with the
5394** page passed as the second argument from oldKey to newKey. If the cache
drhb232c232008-11-19 01:20:26 +00005395** previously contains an entry associated with newKey, it should be
5396** discarded. Any prior cache entry associated with newKey is guaranteed not
5397** to be pinned.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005398**
5399** When SQLite calls the xTruncate() method, the cache must discard all
5400** existing cache entries with page numbers (keys) greater than or equal
5401** to the value of the iLimit parameter passed to xTruncate(). If any
5402** of these pages are pinned, they are implicitly unpinned, meaning that
5403** they can be safely discarded.
5404**
5405** The xDestroy() method is used to delete a cache allocated by xCreate().
5406** All resources associated with the specified cache should be freed. After
drh21614742008-11-18 19:18:08 +00005407** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
danielk1977bc2ca9e2008-11-13 14:28:28 +00005408** handle invalid, and will not use it with any other sqlite3_pcache_methods
5409** functions.
5410*/
5411typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
5412struct sqlite3_pcache_methods {
5413 void *pArg;
5414 int (*xInit)(void*);
5415 void (*xShutdown)(void*);
5416 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
5417 void (*xCachesize)(sqlite3_pcache*, int nCachesize);
5418 int (*xPagecount)(sqlite3_pcache*);
5419 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
5420 void (*xUnpin)(sqlite3_pcache*, void*, int discard);
5421 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
5422 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
5423 void (*xDestroy)(sqlite3_pcache*);
5424};
5425
5426/*
drh27b3b842009-02-03 18:25:13 +00005427** CAPI3REF: Online Backup Object
5428** EXPERIMENTAL
5429**
5430** The sqlite3_backup object records state information about an ongoing
5431** online backup operation. The sqlite3_backup object is created by
5432** a call to [sqlite3_backup_init()] and is destroyed by a call to
5433** [sqlite3_backup_finish()].
drh52224a72009-02-10 13:41:42 +00005434**
5435** See Also: [Using the SQLite Online Backup API]
drh27b3b842009-02-03 18:25:13 +00005436*/
5437typedef struct sqlite3_backup sqlite3_backup;
5438
5439/*
danielk197704103022009-02-03 16:51:24 +00005440** CAPI3REF: Online Backup API.
5441** EXPERIMENTAL
5442**
5443** This API is used to overwrite the contents of one database with that
5444** of another. It is useful either for creating backups of databases or
5445** for copying in-memory databases to or from persistent files.
5446**
drh52224a72009-02-10 13:41:42 +00005447** See Also: [Using the SQLite Online Backup API]
5448**
danielk197704103022009-02-03 16:51:24 +00005449** Exclusive access is required to the destination database for the
5450** duration of the operation. However the source database is only
5451** read-locked while it is actually being read, it is not locked
5452** continuously for the entire operation. Thus, the backup may be
5453** performed on a live database without preventing other users from
5454** writing to the database for an extended period of time.
5455**
5456** To perform a backup operation:
5457** <ol>
drh62b5d2d2009-02-03 18:47:22 +00005458** <li><b>sqlite3_backup_init()</b> is called once to initialize the
5459** backup,
5460** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
danielk197704103022009-02-03 16:51:24 +00005461** the data between the two databases, and finally
drh62b5d2d2009-02-03 18:47:22 +00005462** <li><b>sqlite3_backup_finish()</b> is called to release all resources
danielk197704103022009-02-03 16:51:24 +00005463** associated with the backup operation.
5464** </ol>
5465** There should be exactly one call to sqlite3_backup_finish() for each
5466** successful call to sqlite3_backup_init().
5467**
5468** <b>sqlite3_backup_init()</b>
5469**
5470** The first two arguments passed to [sqlite3_backup_init()] are the database
5471** handle associated with the destination database and the database name
5472** used to attach the destination database to the handle. The database name
5473** is "main" for the main database, "temp" for the temporary database, or
drh62b5d2d2009-02-03 18:47:22 +00005474** the name specified as part of the [ATTACH] statement if the destination is
danielk197704103022009-02-03 16:51:24 +00005475** an attached database. The third and fourth arguments passed to
drh62b5d2d2009-02-03 18:47:22 +00005476** sqlite3_backup_init() identify the [database connection]
5477** and database name used
danielk197704103022009-02-03 16:51:24 +00005478** to access the source database. The values passed for the source and
drh62b5d2d2009-02-03 18:47:22 +00005479** destination [database connection] parameters must not be the same.
danielk197704103022009-02-03 16:51:24 +00005480**
5481** If an error occurs within sqlite3_backup_init(), then NULL is returned
drh62b5d2d2009-02-03 18:47:22 +00005482** and an error code and error message written into the [database connection]
danielk197704103022009-02-03 16:51:24 +00005483** passed as the first argument. They may be retrieved using the
drh62b5d2d2009-02-03 18:47:22 +00005484** [sqlite3_errcode()], [sqlite3_errmsg()], and [sqlite3_errmsg16()] functions.
drh27b3b842009-02-03 18:25:13 +00005485** Otherwise, if successful, a pointer to an [sqlite3_backup] object is
5486** returned. This pointer may be used with the sqlite3_backup_step() and
danielk197704103022009-02-03 16:51:24 +00005487** sqlite3_backup_finish() functions to perform the specified backup
5488** operation.
5489**
5490** <b>sqlite3_backup_step()</b>
5491**
5492** Function [sqlite3_backup_step()] is used to copy up to nPage pages between
5493** the source and destination databases, where nPage is the value of the
danielk197703ab0352009-02-06 05:59:44 +00005494** second parameter passed to sqlite3_backup_step(). If nPage is a negative
5495** value, all remaining source pages are copied. If the required pages are
danielk197704103022009-02-03 16:51:24 +00005496** succesfully copied, but there are still more pages to copy before the
drh62b5d2d2009-02-03 18:47:22 +00005497** backup is complete, it returns [SQLITE_OK]. If no error occured and there
5498** are no more pages to copy, then [SQLITE_DONE] is returned. If an error
5499** occurs, then an SQLite error code is returned. As well as [SQLITE_OK] and
5500** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
5501** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
5502** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
danielk197704103022009-02-03 16:51:24 +00005503**
5504** As well as the case where the destination database file was opened for
drh62b5d2d2009-02-03 18:47:22 +00005505** read-only access, sqlite3_backup_step() may return [SQLITE_READONLY] if
danielk197704103022009-02-03 16:51:24 +00005506** the destination is an in-memory database with a different page size
5507** from the source database.
5508**
5509** If sqlite3_backup_step() cannot obtain a required file-system lock, then
drh62b5d2d2009-02-03 18:47:22 +00005510** the [sqlite3_busy_handler | busy-handler function]
5511** is invoked (if one is specified). If the
danielk197704103022009-02-03 16:51:24 +00005512** busy-handler returns non-zero before the lock is available, then
drh62b5d2d2009-02-03 18:47:22 +00005513** [SQLITE_BUSY] is returned to the caller. In this case the call to
5514** sqlite3_backup_step() can be retried later. If the source
5515** [database connection]
danielk197704103022009-02-03 16:51:24 +00005516** is being used to write to the source database when sqlite3_backup_step()
drh62b5d2d2009-02-03 18:47:22 +00005517** is called, then [SQLITE_LOCKED] is returned immediately. Again, in this
danielk197704103022009-02-03 16:51:24 +00005518** case the call to sqlite3_backup_step() can be retried later on. If
drh62b5d2d2009-02-03 18:47:22 +00005519** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
5520** [SQLITE_READONLY] is returned, then
danielk197704103022009-02-03 16:51:24 +00005521** there is no point in retrying the call to sqlite3_backup_step(). These
5522** errors are considered fatal. At this point the application must accept
5523** that the backup operation has failed and pass the backup operation handle
5524** to the sqlite3_backup_finish() to release associated resources.
5525**
5526** Following the first call to sqlite3_backup_step(), an exclusive lock is
5527** obtained on the destination file. It is not released until either
5528** sqlite3_backup_finish() is called or the backup operation is complete
drh62b5d2d2009-02-03 18:47:22 +00005529** and sqlite3_backup_step() returns [SQLITE_DONE]. Additionally, each time
5530** a call to sqlite3_backup_step() is made a [shared lock] is obtained on
danielk197704103022009-02-03 16:51:24 +00005531** the source database file. This lock is released before the
5532** sqlite3_backup_step() call returns. Because the source database is not
5533** locked between calls to sqlite3_backup_step(), it may be modified mid-way
5534** through the backup procedure. If the source database is modified by an
5535** external process or via a database connection other than the one being
5536** used by the backup operation, then the backup will be transparently
5537** restarted by the next call to sqlite3_backup_step(). If the source
5538** database is modified by the using the same database connection as is used
5539** by the backup operation, then the backup database is transparently
5540** updated at the same time.
5541**
5542** <b>sqlite3_backup_finish()</b>
5543**
drh62b5d2d2009-02-03 18:47:22 +00005544** Once sqlite3_backup_step() has returned [SQLITE_DONE], or when the
drh27b3b842009-02-03 18:25:13 +00005545** application wishes to abandon the backup operation, the [sqlite3_backup]
5546** object should be passed to sqlite3_backup_finish(). This releases all
danielk197704103022009-02-03 16:51:24 +00005547** resources associated with the backup operation. If sqlite3_backup_step()
drh62b5d2d2009-02-03 18:47:22 +00005548** has not yet returned [SQLITE_DONE], then any active write-transaction on the
drh27b3b842009-02-03 18:25:13 +00005549** destination database is rolled back. The [sqlite3_backup] object is invalid
danielk197704103022009-02-03 16:51:24 +00005550** and may not be used following a call to sqlite3_backup_finish().
5551**
drh62b5d2d2009-02-03 18:47:22 +00005552** The value returned by sqlite3_backup_finish is [SQLITE_OK] if no error
5553** occurred, regardless or whether or not sqlite3_backup_step() was called
danielk197704103022009-02-03 16:51:24 +00005554** a sufficient number of times to complete the backup operation. Or, if
5555** an out-of-memory condition or IO error occured during a call to
drh62b5d2d2009-02-03 18:47:22 +00005556** sqlite3_backup_step() then [SQLITE_NOMEM] or an
5557** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] error code
danielk197704103022009-02-03 16:51:24 +00005558** is returned. In this case the error code and an error message are
drh62b5d2d2009-02-03 18:47:22 +00005559** written to the destination [database connection].
danielk197704103022009-02-03 16:51:24 +00005560**
drh62b5d2d2009-02-03 18:47:22 +00005561** A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() is
5562** not a permanent error and does not affect the return value of
danielk197704103022009-02-03 16:51:24 +00005563** sqlite3_backup_finish().
5564**
5565** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
5566**
5567** Each call to sqlite3_backup_step() sets two values stored internally
drh27b3b842009-02-03 18:25:13 +00005568** by an [sqlite3_backup] object. The number of pages still to be backed
danielk197704103022009-02-03 16:51:24 +00005569** up, which may be queried by sqlite3_backup_remaining(), and the total
5570** number of pages in the source database file, which may be queried by
5571** sqlite3_backup_pagecount().
5572**
5573** The values returned by these functions are only updated by
5574** sqlite3_backup_step(). If the source database is modified during a backup
5575** operation, then the values are not updated to account for any extra
5576** pages that need to be updated or the size of the source database file
5577** changing.
5578**
5579** <b>Concurrent Usage of Database Handles</b>
5580**
drh62b5d2d2009-02-03 18:47:22 +00005581** The source [database connection] may be used by the application for other
danielk197704103022009-02-03 16:51:24 +00005582** purposes while a backup operation is underway or being initialized.
5583** If SQLite is compiled and configured to support threadsafe database
5584** connections, then the source database connection may be used concurrently
5585** from within other threads.
5586**
5587** However, the application must guarantee that the destination database
5588** connection handle is not passed to any other API (by any thread) after
5589** sqlite3_backup_init() is called and before the corresponding call to
5590** sqlite3_backup_finish(). Unfortunately SQLite does not currently check
drh62b5d2d2009-02-03 18:47:22 +00005591** for this, if the application does use the destination [database connection]
danielk197704103022009-02-03 16:51:24 +00005592** for some other purpose during a backup operation, things may appear to
drh662c58c2009-02-03 21:13:07 +00005593** work correctly but in fact be subtly malfunctioning. Use of the
5594** destination database connection while a backup is in progress might
5595** also cause a mutex deadlock.
danielk197704103022009-02-03 16:51:24 +00005596**
drh62b5d2d2009-02-03 18:47:22 +00005597** Furthermore, if running in [shared cache mode], the application must
danielk197704103022009-02-03 16:51:24 +00005598** guarantee that the shared cache used by the destination database
5599** is not accessed while the backup is running. In practice this means
5600** that the application must guarantee that the file-system file being
5601** backed up to is not accessed by any connection within the process,
5602** not just the specific connection that was passed to sqlite3_backup_init().
5603**
drh27b3b842009-02-03 18:25:13 +00005604** The [sqlite3_backup] object itself is partially threadsafe. Multiple
danielk197704103022009-02-03 16:51:24 +00005605** threads may safely make multiple concurrent calls to sqlite3_backup_step().
5606** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
5607** APIs are not strictly speaking threadsafe. If they are invoked at the
5608** same time as another thread is invoking sqlite3_backup_step() it is
5609** possible that they return invalid values.
5610*/
danielk197704103022009-02-03 16:51:24 +00005611sqlite3_backup *sqlite3_backup_init(
5612 sqlite3 *pDest, /* Destination database handle */
5613 const char *zDestName, /* Destination database name */
5614 sqlite3 *pSource, /* Source database handle */
5615 const char *zSourceName /* Source database name */
5616);
5617int sqlite3_backup_step(sqlite3_backup *p, int nPage);
5618int sqlite3_backup_finish(sqlite3_backup *p);
5619int sqlite3_backup_remaining(sqlite3_backup *p);
5620int sqlite3_backup_pagecount(sqlite3_backup *p);
5621
5622/*
danielk1977404ca072009-03-16 13:19:36 +00005623** CAPI3REF: Unlock Notification
5624** EXPERIMENTAL
5625**
5626** When running in shared-cache mode, a database operation may fail with
drh89487472009-03-16 13:37:02 +00005627** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
danielk1977404ca072009-03-16 13:19:36 +00005628** individual tables within the shared-cache cannot be obtained. See
5629** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
5630** This API may be used to register a callback that SQLite will invoke
5631** when the connection currently holding the required lock relinquishes it.
5632** This API is only available if the library was compiled with the
drh89487472009-03-16 13:37:02 +00005633** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
danielk1977404ca072009-03-16 13:19:36 +00005634**
5635** See Also: [Using the SQLite Unlock Notification Feature].
5636**
5637** Shared-cache locks are released when a database connection concludes
5638** its current transaction, either by committing it or rolling it back.
5639**
5640** When a connection (known as the blocked connection) fails to obtain a
5641** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
5642** identity of the database connection (the blocking connection) that
5643** has locked the required resource is stored internally. After an
5644** application receives an SQLITE_LOCKED error, it may call the
5645** sqlite3_unlock_notify() method with the blocked connection handle as
5646** the first argument to register for a callback that will be invoked
5647** when the blocking connections current transaction is concluded. The
5648** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
5649** call that concludes the blocking connections transaction.
5650**
5651** If sqlite3_unlock_notify() is called in a multi-threaded application,
5652** there is a chance that the blocking connection will have already
5653** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
5654** If this happens, then the specified callback is invoked immediately,
5655** from within the call to sqlite3_unlock_notify().
5656**
5657** If the blocked connection is attempting to obtain a write-lock on a
5658** shared-cache table, and more than one other connection currently holds
5659** a read-lock on the same table, then SQLite arbitrarily selects one of
5660** the other connections to use as the blocking connection.
5661**
5662** There may be at most one unlock-notify callback registered by a
5663** blocked connection. If sqlite3_unlock_notify() is called when the
5664** blocked connection already has a registered unlock-notify callback,
5665** then the new callback replaces the old. If sqlite3_unlock_notify() is
5666** called with a NULL pointer as its second argument, then any existing
5667** unlock-notify callback is cancelled. The blocked connections
5668** unlock-notify callback may also be canceled by closing the blocked
5669** connection using [sqlite3_close()].
5670**
5671** The unlock-notify callback is not reentrant. If an application invokes
5672** any sqlite3_xxx API functions from within an unlock-notify callback, a
5673** crash or deadlock may be the result.
5674**
5675** Unless deadlock is detected (see below), sqlite3_unlock_notify() always
5676** returns SQLITE_OK.
5677**
5678** <b>Callback Invocation Details</b>
5679**
5680** When an unlock-notify callback is registered, the application provides a
5681** single void* pointer that is passed to the callback when it is invoked.
5682** However, the signature of the callback function allows SQLite to pass
5683** it an array of void* context pointers. The first argument passed to
5684** an unlock-notify callback is a pointer to an array of void* pointers,
5685** and the second is the number of entries in the array.
5686**
5687** When a blocking connections transaction is concluded, there may be
5688** more than one blocked connection that has registered for an unlock-notify
5689** callback. If two or more such blocked connections have specified the
5690** same callback function, then instead of invoking the callback function
5691** multiple times, it is invoked once with the set of void* context pointers
5692** specified by the blocked connections bundled together into an array.
5693** This gives the application an opportunity to prioritize any actions
5694** related to the set of unblocked database connections.
5695**
5696** <b>Deadlock Detection</b>
5697**
5698** Assuming that after registering for an unlock-notify callback a
5699** database waits for the callback to be issued before taking any further
5700** action (a reasonable assumption), then using this API may cause the
5701** application to deadlock. For example, if connection X is waiting for
5702** connection Y's transaction to be concluded, and similarly connection
5703** Y is waiting on connection X's transaction, then neither connection
5704** will proceed and the system may remain deadlocked indefinitely.
5705**
5706** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
5707** detection. If a given call to sqlite3_unlock_notify() would put the
5708** system in a deadlocked state, then SQLITE_LOCKED is returned and no
5709** unlock-notify callback is registered. The system is said to be in
5710** a deadlocked state if connection A has registered for an unlock-notify
5711** callback on the conclusion of connection B's transaction, and connection
5712** B has itself registered for an unlock-notify callback when connection
5713** A's transaction is concluded. Indirect deadlock is also detected, so
5714** the system is also considered to be deadlocked if connection B has
5715** registered for an unlock-notify callback on the conclusion of connection
5716** C's transaction, where connection C is waiting on connection A. Any
5717** number of levels of indirection are allowed.
5718**
5719** <b>The "DROP TABLE" Exception</b>
5720**
5721** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
5722** always appropriate to call sqlite3_unlock_notify(). There is however,
5723** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
5724** SQLite checks if there are any currently executing SELECT statements
5725** that belong to the same connection. If there are, SQLITE_LOCKED is
5726** returned. In this case there is no "blocking connection", so invoking
5727** sqlite3_unlock_notify() results in the unlock-notify callback being
5728** invoked immediately. If the application then re-attempts the "DROP TABLE"
5729** or "DROP INDEX" query, an infinite loop might be the result.
5730**
5731** One way around this problem is to check the extended error code returned
5732** by an sqlite3_step() call. If there is a blocking connection, then the
5733** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
5734** the special "DROP TABLE/INDEX" case, the extended error code is just
5735** SQLITE_LOCKED.
5736*/
5737int sqlite3_unlock_notify(
5738 sqlite3 *pBlocked, /* Waiting connection */
5739 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
5740 void *pNotifyArg /* Argument to pass to xNotify */
5741);
5742
danielk1977ee0484c2009-07-28 16:44:26 +00005743
5744/*
5745** CAPI3REF: String Comparison
5746** EXPERIMENTAL
5747**
5748** The [sqlite3_strnicmp()] API allows applications and extensions to
5749** compare the contents of two buffers containing UTF-8 strings in a
5750** case-indendent fashion, using the same definition of case independence
5751** that SQLite uses internally when comparing identifiers.
5752*/
5753int sqlite3_strnicmp(const char *, const char *, int);
5754
danielk1977404ca072009-03-16 13:19:36 +00005755/*
drhb37df7b2005-10-13 02:09:49 +00005756** Undo the hack that converts floating point types to integer for
5757** builds on processors without floating point support.
5758*/
5759#ifdef SQLITE_OMIT_FLOATING_POINT
5760# undef double
5761#endif
5762
drh382c0242001-10-06 16:33:02 +00005763#ifdef __cplusplus
5764} /* End of the 'extern "C"' block */
5765#endif
danielk19774adee202004-05-08 08:23:19 +00005766#endif