1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/db/sqlite3/src/sqlite3.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,7386 @@
1.4 +/*
1.5 +** 2001 September 15
1.6 +**
1.7 +** The author disclaims copyright to this source code. In place of
1.8 +** a legal notice, here is a blessing:
1.9 +**
1.10 +** May you do good and not evil.
1.11 +** May you find forgiveness for yourself and forgive others.
1.12 +** May you share freely, never taking more than you give.
1.13 +**
1.14 +*************************************************************************
1.15 +** This header file defines the interface that the SQLite library
1.16 +** presents to client programs. If a C-function, structure, datatype,
1.17 +** or constant definition does not appear in this file, then it is
1.18 +** not a published API of SQLite, is subject to change without
1.19 +** notice, and should not be referenced by programs that use SQLite.
1.20 +**
1.21 +** Some of the definitions that are in this file are marked as
1.22 +** "experimental". Experimental interfaces are normally new
1.23 +** features recently added to SQLite. We do not anticipate changes
1.24 +** to experimental interfaces but reserve the right to make minor changes
1.25 +** if experience from use "in the wild" suggest such changes are prudent.
1.26 +**
1.27 +** The official C-language API documentation for SQLite is derived
1.28 +** from comments in this file. This file is the authoritative source
1.29 +** on how SQLite interfaces are suppose to operate.
1.30 +**
1.31 +** The name of this file under configuration management is "sqlite.h.in".
1.32 +** The makefile makes some minor changes to this file (such as inserting
1.33 +** the version number) and changes its name to "sqlite3.h" as
1.34 +** part of the build process.
1.35 +*/
1.36 +#ifndef _SQLITE3_H_
1.37 +#define _SQLITE3_H_
1.38 +#include <stdarg.h> /* Needed for the definition of va_list */
1.39 +
1.40 +/*
1.41 +** Make sure we can call this stuff from C++.
1.42 +*/
1.43 +#ifdef __cplusplus
1.44 +extern "C" {
1.45 +#endif
1.46 +
1.47 +
1.48 +/*
1.49 +** Add the ability to override 'extern'
1.50 +*/
1.51 +#ifndef SQLITE_EXTERN
1.52 +# define SQLITE_EXTERN extern
1.53 +#endif
1.54 +
1.55 +#ifndef SQLITE_API
1.56 +# define SQLITE_API
1.57 +#endif
1.58 +
1.59 +
1.60 +/*
1.61 +** These no-op macros are used in front of interfaces to mark those
1.62 +** interfaces as either deprecated or experimental. New applications
1.63 +** should not use deprecated interfaces - they are support for backwards
1.64 +** compatibility only. Application writers should be aware that
1.65 +** experimental interfaces are subject to change in point releases.
1.66 +**
1.67 +** These macros used to resolve to various kinds of compiler magic that
1.68 +** would generate warning messages when they were used. But that
1.69 +** compiler magic ended up generating such a flurry of bug reports
1.70 +** that we have taken it all out and gone back to using simple
1.71 +** noop macros.
1.72 +*/
1.73 +#define SQLITE_DEPRECATED
1.74 +#define SQLITE_EXPERIMENTAL
1.75 +
1.76 +/*
1.77 +** Ensure these symbols were not defined by some previous header file.
1.78 +*/
1.79 +#ifdef SQLITE_VERSION
1.80 +# undef SQLITE_VERSION
1.81 +#endif
1.82 +#ifdef SQLITE_VERSION_NUMBER
1.83 +# undef SQLITE_VERSION_NUMBER
1.84 +#endif
1.85 +
1.86 +/*
1.87 +** CAPI3REF: Compile-Time Library Version Numbers
1.88 +**
1.89 +** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
1.90 +** evaluates to a string literal that is the SQLite version in the
1.91 +** format "X.Y.Z" where X is the major version number (always 3 for
1.92 +** SQLite3) and Y is the minor version number and Z is the release number.)^
1.93 +** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
1.94 +** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
1.95 +** numbers used in [SQLITE_VERSION].)^
1.96 +** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
1.97 +** be larger than the release from which it is derived. Either Y will
1.98 +** be held constant and Z will be incremented or else Y will be incremented
1.99 +** and Z will be reset to zero.
1.100 +**
1.101 +** Since version 3.6.18, SQLite source code has been stored in the
1.102 +** <a href="http://www.fossil-scm.org/">Fossil configuration management
1.103 +** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
1.104 +** a string which identifies a particular check-in of SQLite
1.105 +** within its configuration management system. ^The SQLITE_SOURCE_ID
1.106 +** string contains the date and time of the check-in (UTC) and an SHA1
1.107 +** hash of the entire source tree.
1.108 +**
1.109 +** See also: [sqlite3_libversion()],
1.110 +** [sqlite3_libversion_number()], [sqlite3_sourceid()],
1.111 +** [sqlite_version()] and [sqlite_source_id()].
1.112 +*/
1.113 +#define SQLITE_VERSION "3.8.4.2"
1.114 +#define SQLITE_VERSION_NUMBER 3008004
1.115 +#define SQLITE_SOURCE_ID "2014-03-26 18:51:19 02ea166372bdb2ef9d8dfbb05e78a97609673a8e"
1.116 +
1.117 +/*
1.118 +** CAPI3REF: Run-Time Library Version Numbers
1.119 +** KEYWORDS: sqlite3_version, sqlite3_sourceid
1.120 +**
1.121 +** These interfaces provide the same information as the [SQLITE_VERSION],
1.122 +** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
1.123 +** but are associated with the library instead of the header file. ^(Cautious
1.124 +** programmers might include assert() statements in their application to
1.125 +** verify that values returned by these interfaces match the macros in
1.126 +** the header, and thus insure that the application is
1.127 +** compiled with matching library and header files.
1.128 +**
1.129 +** <blockquote><pre>
1.130 +** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
1.131 +** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
1.132 +** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
1.133 +** </pre></blockquote>)^
1.134 +**
1.135 +** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
1.136 +** macro. ^The sqlite3_libversion() function returns a pointer to the
1.137 +** to the sqlite3_version[] string constant. The sqlite3_libversion()
1.138 +** function is provided for use in DLLs since DLL users usually do not have
1.139 +** direct access to string constants within the DLL. ^The
1.140 +** sqlite3_libversion_number() function returns an integer equal to
1.141 +** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
1.142 +** a pointer to a string constant whose value is the same as the
1.143 +** [SQLITE_SOURCE_ID] C preprocessor macro.
1.144 +**
1.145 +** See also: [sqlite_version()] and [sqlite_source_id()].
1.146 +*/
1.147 +SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
1.148 +SQLITE_API const char *sqlite3_libversion(void);
1.149 +SQLITE_API const char *sqlite3_sourceid(void);
1.150 +SQLITE_API int sqlite3_libversion_number(void);
1.151 +
1.152 +/*
1.153 +** CAPI3REF: Run-Time Library Compilation Options Diagnostics
1.154 +**
1.155 +** ^The sqlite3_compileoption_used() function returns 0 or 1
1.156 +** indicating whether the specified option was defined at
1.157 +** compile time. ^The SQLITE_ prefix may be omitted from the
1.158 +** option name passed to sqlite3_compileoption_used().
1.159 +**
1.160 +** ^The sqlite3_compileoption_get() function allows iterating
1.161 +** over the list of options that were defined at compile time by
1.162 +** returning the N-th compile time option string. ^If N is out of range,
1.163 +** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
1.164 +** prefix is omitted from any strings returned by
1.165 +** sqlite3_compileoption_get().
1.166 +**
1.167 +** ^Support for the diagnostic functions sqlite3_compileoption_used()
1.168 +** and sqlite3_compileoption_get() may be omitted by specifying the
1.169 +** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
1.170 +**
1.171 +** See also: SQL functions [sqlite_compileoption_used()] and
1.172 +** [sqlite_compileoption_get()] and the [compile_options pragma].
1.173 +*/
1.174 +#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
1.175 +SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
1.176 +SQLITE_API const char *sqlite3_compileoption_get(int N);
1.177 +#endif
1.178 +
1.179 +/*
1.180 +** CAPI3REF: Test To See If The Library Is Threadsafe
1.181 +**
1.182 +** ^The sqlite3_threadsafe() function returns zero if and only if
1.183 +** SQLite was compiled with mutexing code omitted due to the
1.184 +** [SQLITE_THREADSAFE] compile-time option being set to 0.
1.185 +**
1.186 +** SQLite can be compiled with or without mutexes. When
1.187 +** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
1.188 +** are enabled and SQLite is threadsafe. When the
1.189 +** [SQLITE_THREADSAFE] macro is 0,
1.190 +** the mutexes are omitted. Without the mutexes, it is not safe
1.191 +** to use SQLite concurrently from more than one thread.
1.192 +**
1.193 +** Enabling mutexes incurs a measurable performance penalty.
1.194 +** So if speed is of utmost importance, it makes sense to disable
1.195 +** the mutexes. But for maximum safety, mutexes should be enabled.
1.196 +** ^The default behavior is for mutexes to be enabled.
1.197 +**
1.198 +** This interface can be used by an application to make sure that the
1.199 +** version of SQLite that it is linking against was compiled with
1.200 +** the desired setting of the [SQLITE_THREADSAFE] macro.
1.201 +**
1.202 +** This interface only reports on the compile-time mutex setting
1.203 +** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
1.204 +** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
1.205 +** can be fully or partially disabled using a call to [sqlite3_config()]
1.206 +** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
1.207 +** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
1.208 +** sqlite3_threadsafe() function shows only the compile-time setting of
1.209 +** thread safety, not any run-time changes to that setting made by
1.210 +** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
1.211 +** is unchanged by calls to sqlite3_config().)^
1.212 +**
1.213 +** See the [threading mode] documentation for additional information.
1.214 +*/
1.215 +SQLITE_API int sqlite3_threadsafe(void);
1.216 +
1.217 +/*
1.218 +** CAPI3REF: Database Connection Handle
1.219 +** KEYWORDS: {database connection} {database connections}
1.220 +**
1.221 +** Each open SQLite database is represented by a pointer to an instance of
1.222 +** the opaque structure named "sqlite3". It is useful to think of an sqlite3
1.223 +** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
1.224 +** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
1.225 +** and [sqlite3_close_v2()] are its destructors. There are many other
1.226 +** interfaces (such as
1.227 +** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
1.228 +** [sqlite3_busy_timeout()] to name but three) that are methods on an
1.229 +** sqlite3 object.
1.230 +*/
1.231 +typedef struct sqlite3 sqlite3;
1.232 +
1.233 +/*
1.234 +** CAPI3REF: 64-Bit Integer Types
1.235 +** KEYWORDS: sqlite_int64 sqlite_uint64
1.236 +**
1.237 +** Because there is no cross-platform way to specify 64-bit integer types
1.238 +** SQLite includes typedefs for 64-bit signed and unsigned integers.
1.239 +**
1.240 +** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
1.241 +** The sqlite_int64 and sqlite_uint64 types are supported for backwards
1.242 +** compatibility only.
1.243 +**
1.244 +** ^The sqlite3_int64 and sqlite_int64 types can store integer values
1.245 +** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
1.246 +** sqlite3_uint64 and sqlite_uint64 types can store integer values
1.247 +** between 0 and +18446744073709551615 inclusive.
1.248 +*/
1.249 +#ifdef SQLITE_INT64_TYPE
1.250 + typedef SQLITE_INT64_TYPE sqlite_int64;
1.251 + typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
1.252 +#elif defined(_MSC_VER) || defined(__BORLANDC__)
1.253 + typedef __int64 sqlite_int64;
1.254 + typedef unsigned __int64 sqlite_uint64;
1.255 +#else
1.256 + typedef long long int sqlite_int64;
1.257 + typedef unsigned long long int sqlite_uint64;
1.258 +#endif
1.259 +typedef sqlite_int64 sqlite3_int64;
1.260 +typedef sqlite_uint64 sqlite3_uint64;
1.261 +
1.262 +/*
1.263 +** If compiling for a processor that lacks floating point support,
1.264 +** substitute integer for floating-point.
1.265 +*/
1.266 +#ifdef SQLITE_OMIT_FLOATING_POINT
1.267 +# define double sqlite3_int64
1.268 +#endif
1.269 +
1.270 +/*
1.271 +** CAPI3REF: Closing A Database Connection
1.272 +**
1.273 +** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
1.274 +** for the [sqlite3] object.
1.275 +** ^Calls to sqlite3_close() and sqlite3_close_v2() return SQLITE_OK if
1.276 +** the [sqlite3] object is successfully destroyed and all associated
1.277 +** resources are deallocated.
1.278 +**
1.279 +** ^If the database connection is associated with unfinalized prepared
1.280 +** statements or unfinished sqlite3_backup objects then sqlite3_close()
1.281 +** will leave the database connection open and return [SQLITE_BUSY].
1.282 +** ^If sqlite3_close_v2() is called with unfinalized prepared statements
1.283 +** and unfinished sqlite3_backups, then the database connection becomes
1.284 +** an unusable "zombie" which will automatically be deallocated when the
1.285 +** last prepared statement is finalized or the last sqlite3_backup is
1.286 +** finished. The sqlite3_close_v2() interface is intended for use with
1.287 +** host languages that are garbage collected, and where the order in which
1.288 +** destructors are called is arbitrary.
1.289 +**
1.290 +** Applications should [sqlite3_finalize | finalize] all [prepared statements],
1.291 +** [sqlite3_blob_close | close] all [BLOB handles], and
1.292 +** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
1.293 +** with the [sqlite3] object prior to attempting to close the object. ^If
1.294 +** sqlite3_close_v2() is called on a [database connection] that still has
1.295 +** outstanding [prepared statements], [BLOB handles], and/or
1.296 +** [sqlite3_backup] objects then it returns SQLITE_OK but the deallocation
1.297 +** of resources is deferred until all [prepared statements], [BLOB handles],
1.298 +** and [sqlite3_backup] objects are also destroyed.
1.299 +**
1.300 +** ^If an [sqlite3] object is destroyed while a transaction is open,
1.301 +** the transaction is automatically rolled back.
1.302 +**
1.303 +** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
1.304 +** must be either a NULL
1.305 +** pointer or an [sqlite3] object pointer obtained
1.306 +** from [sqlite3_open()], [sqlite3_open16()], or
1.307 +** [sqlite3_open_v2()], and not previously closed.
1.308 +** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
1.309 +** argument is a harmless no-op.
1.310 +*/
1.311 +SQLITE_API int sqlite3_close(sqlite3*);
1.312 +SQLITE_API int sqlite3_close_v2(sqlite3*);
1.313 +
1.314 +/*
1.315 +** The type for a callback function.
1.316 +** This is legacy and deprecated. It is included for historical
1.317 +** compatibility and is not documented.
1.318 +*/
1.319 +typedef int (*sqlite3_callback)(void*,int,char**, char**);
1.320 +
1.321 +/*
1.322 +** CAPI3REF: One-Step Query Execution Interface
1.323 +**
1.324 +** The sqlite3_exec() interface is a convenience wrapper around
1.325 +** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
1.326 +** that allows an application to run multiple statements of SQL
1.327 +** without having to use a lot of C code.
1.328 +**
1.329 +** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
1.330 +** semicolon-separate SQL statements passed into its 2nd argument,
1.331 +** in the context of the [database connection] passed in as its 1st
1.332 +** argument. ^If the callback function of the 3rd argument to
1.333 +** sqlite3_exec() is not NULL, then it is invoked for each result row
1.334 +** coming out of the evaluated SQL statements. ^The 4th argument to
1.335 +** sqlite3_exec() is relayed through to the 1st argument of each
1.336 +** callback invocation. ^If the callback pointer to sqlite3_exec()
1.337 +** is NULL, then no callback is ever invoked and result rows are
1.338 +** ignored.
1.339 +**
1.340 +** ^If an error occurs while evaluating the SQL statements passed into
1.341 +** sqlite3_exec(), then execution of the current statement stops and
1.342 +** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
1.343 +** is not NULL then any error message is written into memory obtained
1.344 +** from [sqlite3_malloc()] and passed back through the 5th parameter.
1.345 +** To avoid memory leaks, the application should invoke [sqlite3_free()]
1.346 +** on error message strings returned through the 5th parameter of
1.347 +** of sqlite3_exec() after the error message string is no longer needed.
1.348 +** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
1.349 +** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
1.350 +** NULL before returning.
1.351 +**
1.352 +** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
1.353 +** routine returns SQLITE_ABORT without invoking the callback again and
1.354 +** without running any subsequent SQL statements.
1.355 +**
1.356 +** ^The 2nd argument to the sqlite3_exec() callback function is the
1.357 +** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
1.358 +** callback is an array of pointers to strings obtained as if from
1.359 +** [sqlite3_column_text()], one for each column. ^If an element of a
1.360 +** result row is NULL then the corresponding string pointer for the
1.361 +** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
1.362 +** sqlite3_exec() callback is an array of pointers to strings where each
1.363 +** entry represents the name of corresponding result column as obtained
1.364 +** from [sqlite3_column_name()].
1.365 +**
1.366 +** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
1.367 +** to an empty string, or a pointer that contains only whitespace and/or
1.368 +** SQL comments, then no SQL statements are evaluated and the database
1.369 +** is not changed.
1.370 +**
1.371 +** Restrictions:
1.372 +**
1.373 +** <ul>
1.374 +** <li> The application must insure that the 1st parameter to sqlite3_exec()
1.375 +** is a valid and open [database connection].
1.376 +** <li> The application must not close the [database connection] specified by
1.377 +** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
1.378 +** <li> The application must not modify the SQL statement text passed into
1.379 +** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
1.380 +** </ul>
1.381 +*/
1.382 +SQLITE_API int sqlite3_exec(
1.383 + sqlite3*, /* An open database */
1.384 + const char *sql, /* SQL to be evaluated */
1.385 + int (*callback)(void*,int,char**,char**), /* Callback function */
1.386 + void *, /* 1st argument to callback */
1.387 + char **errmsg /* Error msg written here */
1.388 +);
1.389 +
1.390 +/*
1.391 +** CAPI3REF: Result Codes
1.392 +** KEYWORDS: SQLITE_OK {error code} {error codes}
1.393 +** KEYWORDS: {result code} {result codes}
1.394 +**
1.395 +** Many SQLite functions return an integer result code from the set shown
1.396 +** here in order to indicate success or failure.
1.397 +**
1.398 +** New error codes may be added in future versions of SQLite.
1.399 +**
1.400 +** See also: [SQLITE_IOERR_READ | extended result codes],
1.401 +** [sqlite3_vtab_on_conflict()] [SQLITE_ROLLBACK | result codes].
1.402 +*/
1.403 +#define SQLITE_OK 0 /* Successful result */
1.404 +/* beginning-of-error-codes */
1.405 +#define SQLITE_ERROR 1 /* SQL error or missing database */
1.406 +#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
1.407 +#define SQLITE_PERM 3 /* Access permission denied */
1.408 +#define SQLITE_ABORT 4 /* Callback routine requested an abort */
1.409 +#define SQLITE_BUSY 5 /* The database file is locked */
1.410 +#define SQLITE_LOCKED 6 /* A table in the database is locked */
1.411 +#define SQLITE_NOMEM 7 /* A malloc() failed */
1.412 +#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
1.413 +#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
1.414 +#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
1.415 +#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
1.416 +#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
1.417 +#define SQLITE_FULL 13 /* Insertion failed because database is full */
1.418 +#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
1.419 +#define SQLITE_PROTOCOL 15 /* Database lock protocol error */
1.420 +#define SQLITE_EMPTY 16 /* Database is empty */
1.421 +#define SQLITE_SCHEMA 17 /* The database schema changed */
1.422 +#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
1.423 +#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
1.424 +#define SQLITE_MISMATCH 20 /* Data type mismatch */
1.425 +#define SQLITE_MISUSE 21 /* Library used incorrectly */
1.426 +#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
1.427 +#define SQLITE_AUTH 23 /* Authorization denied */
1.428 +#define SQLITE_FORMAT 24 /* Auxiliary database format error */
1.429 +#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
1.430 +#define SQLITE_NOTADB 26 /* File opened that is not a database file */
1.431 +#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
1.432 +#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
1.433 +#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
1.434 +#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
1.435 +/* end-of-error-codes */
1.436 +
1.437 +/*
1.438 +** CAPI3REF: Extended Result Codes
1.439 +** KEYWORDS: {extended error code} {extended error codes}
1.440 +** KEYWORDS: {extended result code} {extended result codes}
1.441 +**
1.442 +** In its default configuration, SQLite API routines return one of 26 integer
1.443 +** [SQLITE_OK | result codes]. However, experience has shown that many of
1.444 +** these result codes are too coarse-grained. They do not provide as
1.445 +** much information about problems as programmers might like. In an effort to
1.446 +** address this, newer versions of SQLite (version 3.3.8 and later) include
1.447 +** support for additional result codes that provide more detailed information
1.448 +** about errors. The extended result codes are enabled or disabled
1.449 +** on a per database connection basis using the
1.450 +** [sqlite3_extended_result_codes()] API.
1.451 +**
1.452 +** Some of the available extended result codes are listed here.
1.453 +** One may expect the number of extended result codes will increase
1.454 +** over time. Software that uses extended result codes should expect
1.455 +** to see new result codes in future releases of SQLite.
1.456 +**
1.457 +** The SQLITE_OK result code will never be extended. It will always
1.458 +** be exactly zero.
1.459 +*/
1.460 +#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
1.461 +#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
1.462 +#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
1.463 +#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
1.464 +#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
1.465 +#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
1.466 +#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
1.467 +#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
1.468 +#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
1.469 +#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
1.470 +#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
1.471 +#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
1.472 +#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
1.473 +#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
1.474 +#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
1.475 +#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
1.476 +#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
1.477 +#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
1.478 +#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
1.479 +#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
1.480 +#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
1.481 +#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
1.482 +#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
1.483 +#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
1.484 +#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
1.485 +#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
1.486 +#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
1.487 +#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
1.488 +#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
1.489 +#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
1.490 +#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
1.491 +#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
1.492 +#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
1.493 +#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
1.494 +#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
1.495 +#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
1.496 +#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
1.497 +#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
1.498 +#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
1.499 +#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
1.500 +#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
1.501 +#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
1.502 +#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
1.503 +#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
1.504 +#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
1.505 +#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
1.506 +#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
1.507 +#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
1.508 +#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
1.509 +#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
1.510 +#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
1.511 +#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
1.512 +
1.513 +/*
1.514 +** CAPI3REF: Flags For File Open Operations
1.515 +**
1.516 +** These bit values are intended for use in the
1.517 +** 3rd parameter to the [sqlite3_open_v2()] interface and
1.518 +** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
1.519 +*/
1.520 +#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
1.521 +#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
1.522 +#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
1.523 +#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
1.524 +#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
1.525 +#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
1.526 +#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
1.527 +#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
1.528 +#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
1.529 +#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
1.530 +#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
1.531 +#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
1.532 +#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
1.533 +#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
1.534 +#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
1.535 +#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
1.536 +#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
1.537 +#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
1.538 +#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
1.539 +#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
1.540 +
1.541 +/* Reserved: 0x00F00000 */
1.542 +
1.543 +/*
1.544 +** CAPI3REF: Device Characteristics
1.545 +**
1.546 +** The xDeviceCharacteristics method of the [sqlite3_io_methods]
1.547 +** object returns an integer which is a vector of these
1.548 +** bit values expressing I/O characteristics of the mass storage
1.549 +** device that holds the file that the [sqlite3_io_methods]
1.550 +** refers to.
1.551 +**
1.552 +** The SQLITE_IOCAP_ATOMIC property means that all writes of
1.553 +** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
1.554 +** mean that writes of blocks that are nnn bytes in size and
1.555 +** are aligned to an address which is an integer multiple of
1.556 +** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
1.557 +** that when data is appended to a file, the data is appended
1.558 +** first then the size of the file is extended, never the other
1.559 +** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
1.560 +** information is written to disk in the same order as calls
1.561 +** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
1.562 +** after reboot following a crash or power loss, the only bytes in a
1.563 +** file that were written at the application level might have changed
1.564 +** and that adjacent bytes, even bytes within the same sector are
1.565 +** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
1.566 +** flag indicate that a file cannot be deleted when open.
1.567 +*/
1.568 +#define SQLITE_IOCAP_ATOMIC 0x00000001
1.569 +#define SQLITE_IOCAP_ATOMIC512 0x00000002
1.570 +#define SQLITE_IOCAP_ATOMIC1K 0x00000004
1.571 +#define SQLITE_IOCAP_ATOMIC2K 0x00000008
1.572 +#define SQLITE_IOCAP_ATOMIC4K 0x00000010
1.573 +#define SQLITE_IOCAP_ATOMIC8K 0x00000020
1.574 +#define SQLITE_IOCAP_ATOMIC16K 0x00000040
1.575 +#define SQLITE_IOCAP_ATOMIC32K 0x00000080
1.576 +#define SQLITE_IOCAP_ATOMIC64K 0x00000100
1.577 +#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
1.578 +#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
1.579 +#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
1.580 +#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
1.581 +
1.582 +/*
1.583 +** CAPI3REF: File Locking Levels
1.584 +**
1.585 +** SQLite uses one of these integer values as the second
1.586 +** argument to calls it makes to the xLock() and xUnlock() methods
1.587 +** of an [sqlite3_io_methods] object.
1.588 +*/
1.589 +#define SQLITE_LOCK_NONE 0
1.590 +#define SQLITE_LOCK_SHARED 1
1.591 +#define SQLITE_LOCK_RESERVED 2
1.592 +#define SQLITE_LOCK_PENDING 3
1.593 +#define SQLITE_LOCK_EXCLUSIVE 4
1.594 +
1.595 +/*
1.596 +** CAPI3REF: Synchronization Type Flags
1.597 +**
1.598 +** When SQLite invokes the xSync() method of an
1.599 +** [sqlite3_io_methods] object it uses a combination of
1.600 +** these integer values as the second argument.
1.601 +**
1.602 +** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
1.603 +** sync operation only needs to flush data to mass storage. Inode
1.604 +** information need not be flushed. If the lower four bits of the flag
1.605 +** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
1.606 +** If the lower four bits equal SQLITE_SYNC_FULL, that means
1.607 +** to use Mac OS X style fullsync instead of fsync().
1.608 +**
1.609 +** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
1.610 +** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
1.611 +** settings. The [synchronous pragma] determines when calls to the
1.612 +** xSync VFS method occur and applies uniformly across all platforms.
1.613 +** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
1.614 +** energetic or rigorous or forceful the sync operations are and
1.615 +** only make a difference on Mac OSX for the default SQLite code.
1.616 +** (Third-party VFS implementations might also make the distinction
1.617 +** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
1.618 +** operating systems natively supported by SQLite, only Mac OSX
1.619 +** cares about the difference.)
1.620 +*/
1.621 +#define SQLITE_SYNC_NORMAL 0x00002
1.622 +#define SQLITE_SYNC_FULL 0x00003
1.623 +#define SQLITE_SYNC_DATAONLY 0x00010
1.624 +
1.625 +/*
1.626 +** CAPI3REF: OS Interface Open File Handle
1.627 +**
1.628 +** An [sqlite3_file] object represents an open file in the
1.629 +** [sqlite3_vfs | OS interface layer]. Individual OS interface
1.630 +** implementations will
1.631 +** want to subclass this object by appending additional fields
1.632 +** for their own use. The pMethods entry is a pointer to an
1.633 +** [sqlite3_io_methods] object that defines methods for performing
1.634 +** I/O operations on the open file.
1.635 +*/
1.636 +typedef struct sqlite3_file sqlite3_file;
1.637 +struct sqlite3_file {
1.638 + const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
1.639 +};
1.640 +
1.641 +/*
1.642 +** CAPI3REF: OS Interface File Virtual Methods Object
1.643 +**
1.644 +** Every file opened by the [sqlite3_vfs.xOpen] method populates an
1.645 +** [sqlite3_file] object (or, more commonly, a subclass of the
1.646 +** [sqlite3_file] object) with a pointer to an instance of this object.
1.647 +** This object defines the methods used to perform various operations
1.648 +** against the open file represented by the [sqlite3_file] object.
1.649 +**
1.650 +** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
1.651 +** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
1.652 +** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
1.653 +** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
1.654 +** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
1.655 +** to NULL.
1.656 +**
1.657 +** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
1.658 +** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
1.659 +** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
1.660 +** flag may be ORed in to indicate that only the data of the file
1.661 +** and not its inode needs to be synced.
1.662 +**
1.663 +** The integer values to xLock() and xUnlock() are one of
1.664 +** <ul>
1.665 +** <li> [SQLITE_LOCK_NONE],
1.666 +** <li> [SQLITE_LOCK_SHARED],
1.667 +** <li> [SQLITE_LOCK_RESERVED],
1.668 +** <li> [SQLITE_LOCK_PENDING], or
1.669 +** <li> [SQLITE_LOCK_EXCLUSIVE].
1.670 +** </ul>
1.671 +** xLock() increases the lock. xUnlock() decreases the lock.
1.672 +** The xCheckReservedLock() method checks whether any database connection,
1.673 +** either in this process or in some other process, is holding a RESERVED,
1.674 +** PENDING, or EXCLUSIVE lock on the file. It returns true
1.675 +** if such a lock exists and false otherwise.
1.676 +**
1.677 +** The xFileControl() method is a generic interface that allows custom
1.678 +** VFS implementations to directly control an open file using the
1.679 +** [sqlite3_file_control()] interface. The second "op" argument is an
1.680 +** integer opcode. The third argument is a generic pointer intended to
1.681 +** point to a structure that may contain arguments or space in which to
1.682 +** write return values. Potential uses for xFileControl() might be
1.683 +** functions to enable blocking locks with timeouts, to change the
1.684 +** locking strategy (for example to use dot-file locks), to inquire
1.685 +** about the status of a lock, or to break stale locks. The SQLite
1.686 +** core reserves all opcodes less than 100 for its own use.
1.687 +** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
1.688 +** Applications that define a custom xFileControl method should use opcodes
1.689 +** greater than 100 to avoid conflicts. VFS implementations should
1.690 +** return [SQLITE_NOTFOUND] for file control opcodes that they do not
1.691 +** recognize.
1.692 +**
1.693 +** The xSectorSize() method returns the sector size of the
1.694 +** device that underlies the file. The sector size is the
1.695 +** minimum write that can be performed without disturbing
1.696 +** other bytes in the file. The xDeviceCharacteristics()
1.697 +** method returns a bit vector describing behaviors of the
1.698 +** underlying device:
1.699 +**
1.700 +** <ul>
1.701 +** <li> [SQLITE_IOCAP_ATOMIC]
1.702 +** <li> [SQLITE_IOCAP_ATOMIC512]
1.703 +** <li> [SQLITE_IOCAP_ATOMIC1K]
1.704 +** <li> [SQLITE_IOCAP_ATOMIC2K]
1.705 +** <li> [SQLITE_IOCAP_ATOMIC4K]
1.706 +** <li> [SQLITE_IOCAP_ATOMIC8K]
1.707 +** <li> [SQLITE_IOCAP_ATOMIC16K]
1.708 +** <li> [SQLITE_IOCAP_ATOMIC32K]
1.709 +** <li> [SQLITE_IOCAP_ATOMIC64K]
1.710 +** <li> [SQLITE_IOCAP_SAFE_APPEND]
1.711 +** <li> [SQLITE_IOCAP_SEQUENTIAL]
1.712 +** </ul>
1.713 +**
1.714 +** The SQLITE_IOCAP_ATOMIC property means that all writes of
1.715 +** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
1.716 +** mean that writes of blocks that are nnn bytes in size and
1.717 +** are aligned to an address which is an integer multiple of
1.718 +** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
1.719 +** that when data is appended to a file, the data is appended
1.720 +** first then the size of the file is extended, never the other
1.721 +** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
1.722 +** information is written to disk in the same order as calls
1.723 +** to xWrite().
1.724 +**
1.725 +** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
1.726 +** in the unread portions of the buffer with zeros. A VFS that
1.727 +** fails to zero-fill short reads might seem to work. However,
1.728 +** failure to zero-fill short reads will eventually lead to
1.729 +** database corruption.
1.730 +*/
1.731 +typedef struct sqlite3_io_methods sqlite3_io_methods;
1.732 +struct sqlite3_io_methods {
1.733 + int iVersion;
1.734 + int (*xClose)(sqlite3_file*);
1.735 + int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
1.736 + int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
1.737 + int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
1.738 + int (*xSync)(sqlite3_file*, int flags);
1.739 + int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
1.740 + int (*xLock)(sqlite3_file*, int);
1.741 + int (*xUnlock)(sqlite3_file*, int);
1.742 + int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
1.743 + int (*xFileControl)(sqlite3_file*, int op, void *pArg);
1.744 + int (*xSectorSize)(sqlite3_file*);
1.745 + int (*xDeviceCharacteristics)(sqlite3_file*);
1.746 + /* Methods above are valid for version 1 */
1.747 + int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
1.748 + int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
1.749 + void (*xShmBarrier)(sqlite3_file*);
1.750 + int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
1.751 + /* Methods above are valid for version 2 */
1.752 + int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
1.753 + int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
1.754 + /* Methods above are valid for version 3 */
1.755 + /* Additional methods may be added in future releases */
1.756 +};
1.757 +
1.758 +/*
1.759 +** CAPI3REF: Standard File Control Opcodes
1.760 +**
1.761 +** These integer constants are opcodes for the xFileControl method
1.762 +** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
1.763 +** interface.
1.764 +**
1.765 +** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
1.766 +** opcode causes the xFileControl method to write the current state of
1.767 +** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
1.768 +** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
1.769 +** into an integer that the pArg argument points to. This capability
1.770 +** is used during testing and only needs to be supported when SQLITE_TEST
1.771 +** is defined.
1.772 +** <ul>
1.773 +** <li>[[SQLITE_FCNTL_SIZE_HINT]]
1.774 +** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
1.775 +** layer a hint of how large the database file will grow to be during the
1.776 +** current transaction. This hint is not guaranteed to be accurate but it
1.777 +** is often close. The underlying VFS might choose to preallocate database
1.778 +** file space based on this hint in order to help writes to the database
1.779 +** file run faster.
1.780 +**
1.781 +** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
1.782 +** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
1.783 +** extends and truncates the database file in chunks of a size specified
1.784 +** by the user. The fourth argument to [sqlite3_file_control()] should
1.785 +** point to an integer (type int) containing the new chunk-size to use
1.786 +** for the nominated database. Allocating database file space in large
1.787 +** chunks (say 1MB at a time), may reduce file-system fragmentation and
1.788 +** improve performance on some systems.
1.789 +**
1.790 +** <li>[[SQLITE_FCNTL_FILE_POINTER]]
1.791 +** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
1.792 +** to the [sqlite3_file] object associated with a particular database
1.793 +** connection. See the [sqlite3_file_control()] documentation for
1.794 +** additional information.
1.795 +**
1.796 +** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
1.797 +** No longer in use.
1.798 +**
1.799 +** <li>[[SQLITE_FCNTL_SYNC]]
1.800 +** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
1.801 +** sent to the VFS immediately before the xSync method is invoked on a
1.802 +** database file descriptor. Or, if the xSync method is not invoked
1.803 +** because the user has configured SQLite with
1.804 +** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
1.805 +** of the xSync method. In most cases, the pointer argument passed with
1.806 +** this file-control is NULL. However, if the database file is being synced
1.807 +** as part of a multi-database commit, the argument points to a nul-terminated
1.808 +** string containing the transactions master-journal file name. VFSes that
1.809 +** do not need this signal should silently ignore this opcode. Applications
1.810 +** should not call [sqlite3_file_control()] with this opcode as doing so may
1.811 +** disrupt the operation of the specialized VFSes that do require it.
1.812 +**
1.813 +** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
1.814 +** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
1.815 +** and sent to the VFS after a transaction has been committed immediately
1.816 +** but before the database is unlocked. VFSes that do not need this signal
1.817 +** should silently ignore this opcode. Applications should not call
1.818 +** [sqlite3_file_control()] with this opcode as doing so may disrupt the
1.819 +** operation of the specialized VFSes that do require it.
1.820 +**
1.821 +** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
1.822 +** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
1.823 +** retry counts and intervals for certain disk I/O operations for the
1.824 +** windows [VFS] in order to provide robustness in the presence of
1.825 +** anti-virus programs. By default, the windows VFS will retry file read,
1.826 +** file write, and file delete operations up to 10 times, with a delay
1.827 +** of 25 milliseconds before the first retry and with the delay increasing
1.828 +** by an additional 25 milliseconds with each subsequent retry. This
1.829 +** opcode allows these two values (10 retries and 25 milliseconds of delay)
1.830 +** to be adjusted. The values are changed for all database connections
1.831 +** within the same process. The argument is a pointer to an array of two
1.832 +** integers where the first integer i the new retry count and the second
1.833 +** integer is the delay. If either integer is negative, then the setting
1.834 +** is not changed but instead the prior value of that setting is written
1.835 +** into the array entry, allowing the current retry settings to be
1.836 +** interrogated. The zDbName parameter is ignored.
1.837 +**
1.838 +** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
1.839 +** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
1.840 +** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
1.841 +** write ahead log and shared memory files used for transaction control
1.842 +** are automatically deleted when the latest connection to the database
1.843 +** closes. Setting persistent WAL mode causes those files to persist after
1.844 +** close. Persisting the files is useful when other processes that do not
1.845 +** have write permission on the directory containing the database file want
1.846 +** to read the database file, as the WAL and shared memory files must exist
1.847 +** in order for the database to be readable. The fourth parameter to
1.848 +** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1.849 +** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
1.850 +** WAL mode. If the integer is -1, then it is overwritten with the current
1.851 +** WAL persistence setting.
1.852 +**
1.853 +** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
1.854 +** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
1.855 +** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
1.856 +** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
1.857 +** xDeviceCharacteristics methods. The fourth parameter to
1.858 +** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1.859 +** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
1.860 +** mode. If the integer is -1, then it is overwritten with the current
1.861 +** zero-damage mode setting.
1.862 +**
1.863 +** <li>[[SQLITE_FCNTL_OVERWRITE]]
1.864 +** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
1.865 +** a write transaction to indicate that, unless it is rolled back for some
1.866 +** reason, the entire database file will be overwritten by the current
1.867 +** transaction. This is used by VACUUM operations.
1.868 +**
1.869 +** <li>[[SQLITE_FCNTL_VFSNAME]]
1.870 +** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
1.871 +** all [VFSes] in the VFS stack. The names are of all VFS shims and the
1.872 +** final bottom-level VFS are written into memory obtained from
1.873 +** [sqlite3_malloc()] and the result is stored in the char* variable
1.874 +** that the fourth parameter of [sqlite3_file_control()] points to.
1.875 +** The caller is responsible for freeing the memory when done. As with
1.876 +** all file-control actions, there is no guarantee that this will actually
1.877 +** do anything. Callers should initialize the char* variable to a NULL
1.878 +** pointer in case this file-control is not implemented. This file-control
1.879 +** is intended for diagnostic use only.
1.880 +**
1.881 +** <li>[[SQLITE_FCNTL_PRAGMA]]
1.882 +** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1.883 +** file control is sent to the open [sqlite3_file] object corresponding
1.884 +** to the database file to which the pragma statement refers. ^The argument
1.885 +** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1.886 +** pointers to strings (char**) in which the second element of the array
1.887 +** is the name of the pragma and the third element is the argument to the
1.888 +** pragma or NULL if the pragma has no argument. ^The handler for an
1.889 +** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1.890 +** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1.891 +** or the equivalent and that string will become the result of the pragma or
1.892 +** the error message if the pragma fails. ^If the
1.893 +** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1.894 +** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
1.895 +** file control returns [SQLITE_OK], then the parser assumes that the
1.896 +** VFS has handled the PRAGMA itself and the parser generates a no-op
1.897 +** prepared statement. ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1.898 +** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1.899 +** that the VFS encountered an error while handling the [PRAGMA] and the
1.900 +** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
1.901 +** file control occurs at the beginning of pragma statement analysis and so
1.902 +** it is able to override built-in [PRAGMA] statements.
1.903 +**
1.904 +** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1.905 +** ^The [SQLITE_FCNTL_BUSYHANDLER]
1.906 +** file-control may be invoked by SQLite on the database file handle
1.907 +** shortly after it is opened in order to provide a custom VFS with access
1.908 +** to the connections busy-handler callback. The argument is of type (void **)
1.909 +** - an array of two (void *) values. The first (void *) actually points
1.910 +** to a function of type (int (*)(void *)). In order to invoke the connections
1.911 +** busy-handler, this function should be invoked with the second (void *) in
1.912 +** the array as the only argument. If it returns non-zero, then the operation
1.913 +** should be retried. If it returns zero, the custom VFS should abandon the
1.914 +** current operation.
1.915 +**
1.916 +** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1.917 +** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1.918 +** to have SQLite generate a
1.919 +** temporary filename using the same algorithm that is followed to generate
1.920 +** temporary filenames for TEMP tables and other internal uses. The
1.921 +** argument should be a char** which will be filled with the filename
1.922 +** written into memory obtained from [sqlite3_malloc()]. The caller should
1.923 +** invoke [sqlite3_free()] on the result to avoid a memory leak.
1.924 +**
1.925 +** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1.926 +** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1.927 +** maximum number of bytes that will be used for memory-mapped I/O.
1.928 +** The argument is a pointer to a value of type sqlite3_int64 that
1.929 +** is an advisory maximum number of bytes in the file to memory map. The
1.930 +** pointer is overwritten with the old value. The limit is not changed if
1.931 +** the value originally pointed to is negative, and so the current limit
1.932 +** can be queried by passing in a pointer to a negative number. This
1.933 +** file-control is used internally to implement [PRAGMA mmap_size].
1.934 +**
1.935 +** <li>[[SQLITE_FCNTL_TRACE]]
1.936 +** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1.937 +** to the VFS about what the higher layers of the SQLite stack are doing.
1.938 +** This file control is used by some VFS activity tracing [shims].
1.939 +** The argument is a zero-terminated string. Higher layers in the
1.940 +** SQLite stack may generate instances of this file control if
1.941 +** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1.942 +**
1.943 +** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1.944 +** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1.945 +** pointer to an integer and it writes a boolean into that integer depending
1.946 +** on whether or not the file has been renamed, moved, or deleted since it
1.947 +** was first opened.
1.948 +**
1.949 +** </ul>
1.950 +*/
1.951 +#define SQLITE_FCNTL_LOCKSTATE 1
1.952 +#define SQLITE_GET_LOCKPROXYFILE 2
1.953 +#define SQLITE_SET_LOCKPROXYFILE 3
1.954 +#define SQLITE_LAST_ERRNO 4
1.955 +#define SQLITE_FCNTL_SIZE_HINT 5
1.956 +#define SQLITE_FCNTL_CHUNK_SIZE 6
1.957 +#define SQLITE_FCNTL_FILE_POINTER 7
1.958 +#define SQLITE_FCNTL_SYNC_OMITTED 8
1.959 +#define SQLITE_FCNTL_WIN32_AV_RETRY 9
1.960 +#define SQLITE_FCNTL_PERSIST_WAL 10
1.961 +#define SQLITE_FCNTL_OVERWRITE 11
1.962 +#define SQLITE_FCNTL_VFSNAME 12
1.963 +#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
1.964 +#define SQLITE_FCNTL_PRAGMA 14
1.965 +#define SQLITE_FCNTL_BUSYHANDLER 15
1.966 +#define SQLITE_FCNTL_TEMPFILENAME 16
1.967 +#define SQLITE_FCNTL_MMAP_SIZE 18
1.968 +#define SQLITE_FCNTL_TRACE 19
1.969 +#define SQLITE_FCNTL_HAS_MOVED 20
1.970 +#define SQLITE_FCNTL_SYNC 21
1.971 +#define SQLITE_FCNTL_COMMIT_PHASETWO 22
1.972 +
1.973 +/*
1.974 +** CAPI3REF: Mutex Handle
1.975 +**
1.976 +** The mutex module within SQLite defines [sqlite3_mutex] to be an
1.977 +** abstract type for a mutex object. The SQLite core never looks
1.978 +** at the internal representation of an [sqlite3_mutex]. It only
1.979 +** deals with pointers to the [sqlite3_mutex] object.
1.980 +**
1.981 +** Mutexes are created using [sqlite3_mutex_alloc()].
1.982 +*/
1.983 +typedef struct sqlite3_mutex sqlite3_mutex;
1.984 +
1.985 +/*
1.986 +** CAPI3REF: OS Interface Object
1.987 +**
1.988 +** An instance of the sqlite3_vfs object defines the interface between
1.989 +** the SQLite core and the underlying operating system. The "vfs"
1.990 +** in the name of the object stands for "virtual file system". See
1.991 +** the [VFS | VFS documentation] for further information.
1.992 +**
1.993 +** The value of the iVersion field is initially 1 but may be larger in
1.994 +** future versions of SQLite. Additional fields may be appended to this
1.995 +** object when the iVersion value is increased. Note that the structure
1.996 +** of the sqlite3_vfs object changes in the transaction between
1.997 +** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
1.998 +** modified.
1.999 +**
1.1000 +** The szOsFile field is the size of the subclassed [sqlite3_file]
1.1001 +** structure used by this VFS. mxPathname is the maximum length of
1.1002 +** a pathname in this VFS.
1.1003 +**
1.1004 +** Registered sqlite3_vfs objects are kept on a linked list formed by
1.1005 +** the pNext pointer. The [sqlite3_vfs_register()]
1.1006 +** and [sqlite3_vfs_unregister()] interfaces manage this list
1.1007 +** in a thread-safe way. The [sqlite3_vfs_find()] interface
1.1008 +** searches the list. Neither the application code nor the VFS
1.1009 +** implementation should use the pNext pointer.
1.1010 +**
1.1011 +** The pNext field is the only field in the sqlite3_vfs
1.1012 +** structure that SQLite will ever modify. SQLite will only access
1.1013 +** or modify this field while holding a particular static mutex.
1.1014 +** The application should never modify anything within the sqlite3_vfs
1.1015 +** object once the object has been registered.
1.1016 +**
1.1017 +** The zName field holds the name of the VFS module. The name must
1.1018 +** be unique across all VFS modules.
1.1019 +**
1.1020 +** [[sqlite3_vfs.xOpen]]
1.1021 +** ^SQLite guarantees that the zFilename parameter to xOpen
1.1022 +** is either a NULL pointer or string obtained
1.1023 +** from xFullPathname() with an optional suffix added.
1.1024 +** ^If a suffix is added to the zFilename parameter, it will
1.1025 +** consist of a single "-" character followed by no more than
1.1026 +** 11 alphanumeric and/or "-" characters.
1.1027 +** ^SQLite further guarantees that
1.1028 +** the string will be valid and unchanged until xClose() is
1.1029 +** called. Because of the previous sentence,
1.1030 +** the [sqlite3_file] can safely store a pointer to the
1.1031 +** filename if it needs to remember the filename for some reason.
1.1032 +** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1.1033 +** must invent its own temporary name for the file. ^Whenever the
1.1034 +** xFilename parameter is NULL it will also be the case that the
1.1035 +** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1.1036 +**
1.1037 +** The flags argument to xOpen() includes all bits set in
1.1038 +** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
1.1039 +** or [sqlite3_open16()] is used, then flags includes at least
1.1040 +** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1.1041 +** If xOpen() opens a file read-only then it sets *pOutFlags to
1.1042 +** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
1.1043 +**
1.1044 +** ^(SQLite will also add one of the following flags to the xOpen()
1.1045 +** call, depending on the object being opened:
1.1046 +**
1.1047 +** <ul>
1.1048 +** <li> [SQLITE_OPEN_MAIN_DB]
1.1049 +** <li> [SQLITE_OPEN_MAIN_JOURNAL]
1.1050 +** <li> [SQLITE_OPEN_TEMP_DB]
1.1051 +** <li> [SQLITE_OPEN_TEMP_JOURNAL]
1.1052 +** <li> [SQLITE_OPEN_TRANSIENT_DB]
1.1053 +** <li> [SQLITE_OPEN_SUBJOURNAL]
1.1054 +** <li> [SQLITE_OPEN_MASTER_JOURNAL]
1.1055 +** <li> [SQLITE_OPEN_WAL]
1.1056 +** </ul>)^
1.1057 +**
1.1058 +** The file I/O implementation can use the object type flags to
1.1059 +** change the way it deals with files. For example, an application
1.1060 +** that does not care about crash recovery or rollback might make
1.1061 +** the open of a journal file a no-op. Writes to this journal would
1.1062 +** also be no-ops, and any attempt to read the journal would return
1.1063 +** SQLITE_IOERR. Or the implementation might recognize that a database
1.1064 +** file will be doing page-aligned sector reads and writes in a random
1.1065 +** order and set up its I/O subsystem accordingly.
1.1066 +**
1.1067 +** SQLite might also add one of the following flags to the xOpen method:
1.1068 +**
1.1069 +** <ul>
1.1070 +** <li> [SQLITE_OPEN_DELETEONCLOSE]
1.1071 +** <li> [SQLITE_OPEN_EXCLUSIVE]
1.1072 +** </ul>
1.1073 +**
1.1074 +** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1.1075 +** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
1.1076 +** will be set for TEMP databases and their journals, transient
1.1077 +** databases, and subjournals.
1.1078 +**
1.1079 +** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1.1080 +** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1.1081 +** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1.1082 +** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1.1083 +** SQLITE_OPEN_CREATE, is used to indicate that file should always
1.1084 +** be created, and that it is an error if it already exists.
1.1085 +** It is <i>not</i> used to indicate the file should be opened
1.1086 +** for exclusive access.
1.1087 +**
1.1088 +** ^At least szOsFile bytes of memory are allocated by SQLite
1.1089 +** to hold the [sqlite3_file] structure passed as the third
1.1090 +** argument to xOpen. The xOpen method does not have to
1.1091 +** allocate the structure; it should just fill it in. Note that
1.1092 +** the xOpen method must set the sqlite3_file.pMethods to either
1.1093 +** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
1.1094 +** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
1.1095 +** element will be valid after xOpen returns regardless of the success
1.1096 +** or failure of the xOpen call.
1.1097 +**
1.1098 +** [[sqlite3_vfs.xAccess]]
1.1099 +** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1.1100 +** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1.1101 +** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1.1102 +** to test whether a file is at least readable. The file can be a
1.1103 +** directory.
1.1104 +**
1.1105 +** ^SQLite will always allocate at least mxPathname+1 bytes for the
1.1106 +** output buffer xFullPathname. The exact size of the output buffer
1.1107 +** is also passed as a parameter to both methods. If the output buffer
1.1108 +** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1.1109 +** handled as a fatal error by SQLite, vfs implementations should endeavor
1.1110 +** to prevent this by setting mxPathname to a sufficiently large value.
1.1111 +**
1.1112 +** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1.1113 +** interfaces are not strictly a part of the filesystem, but they are
1.1114 +** included in the VFS structure for completeness.
1.1115 +** The xRandomness() function attempts to return nBytes bytes
1.1116 +** of good-quality randomness into zOut. The return value is
1.1117 +** the actual number of bytes of randomness obtained.
1.1118 +** The xSleep() method causes the calling thread to sleep for at
1.1119 +** least the number of microseconds given. ^The xCurrentTime()
1.1120 +** method returns a Julian Day Number for the current date and time as
1.1121 +** a floating point value.
1.1122 +** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1.1123 +** Day Number multiplied by 86400000 (the number of milliseconds in
1.1124 +** a 24-hour day).
1.1125 +** ^SQLite will use the xCurrentTimeInt64() method to get the current
1.1126 +** date and time if that method is available (if iVersion is 2 or
1.1127 +** greater and the function pointer is not NULL) and will fall back
1.1128 +** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1.1129 +**
1.1130 +** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1.1131 +** are not used by the SQLite core. These optional interfaces are provided
1.1132 +** by some VFSes to facilitate testing of the VFS code. By overriding
1.1133 +** system calls with functions under its control, a test program can
1.1134 +** simulate faults and error conditions that would otherwise be difficult
1.1135 +** or impossible to induce. The set of system calls that can be overridden
1.1136 +** varies from one VFS to another, and from one version of the same VFS to the
1.1137 +** next. Applications that use these interfaces must be prepared for any
1.1138 +** or all of these interfaces to be NULL or for their behavior to change
1.1139 +** from one release to the next. Applications must not attempt to access
1.1140 +** any of these methods if the iVersion of the VFS is less than 3.
1.1141 +*/
1.1142 +typedef struct sqlite3_vfs sqlite3_vfs;
1.1143 +typedef void (*sqlite3_syscall_ptr)(void);
1.1144 +struct sqlite3_vfs {
1.1145 + int iVersion; /* Structure version number (currently 3) */
1.1146 + int szOsFile; /* Size of subclassed sqlite3_file */
1.1147 + int mxPathname; /* Maximum file pathname length */
1.1148 + sqlite3_vfs *pNext; /* Next registered VFS */
1.1149 + const char *zName; /* Name of this virtual file system */
1.1150 + void *pAppData; /* Pointer to application-specific data */
1.1151 + int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1.1152 + int flags, int *pOutFlags);
1.1153 + int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1.1154 + int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1.1155 + int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1.1156 + void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1.1157 + void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1.1158 + void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1.1159 + void (*xDlClose)(sqlite3_vfs*, void*);
1.1160 + int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1.1161 + int (*xSleep)(sqlite3_vfs*, int microseconds);
1.1162 + int (*xCurrentTime)(sqlite3_vfs*, double*);
1.1163 + int (*xGetLastError)(sqlite3_vfs*, int, char *);
1.1164 + /*
1.1165 + ** The methods above are in version 1 of the sqlite_vfs object
1.1166 + ** definition. Those that follow are added in version 2 or later
1.1167 + */
1.1168 + int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1.1169 + /*
1.1170 + ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1.1171 + ** Those below are for version 3 and greater.
1.1172 + */
1.1173 + int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1.1174 + sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1.1175 + const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1.1176 + /*
1.1177 + ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1.1178 + ** New fields may be appended in figure versions. The iVersion
1.1179 + ** value will increment whenever this happens.
1.1180 + */
1.1181 +};
1.1182 +
1.1183 +/*
1.1184 +** CAPI3REF: Flags for the xAccess VFS method
1.1185 +**
1.1186 +** These integer constants can be used as the third parameter to
1.1187 +** the xAccess method of an [sqlite3_vfs] object. They determine
1.1188 +** what kind of permissions the xAccess method is looking for.
1.1189 +** With SQLITE_ACCESS_EXISTS, the xAccess method
1.1190 +** simply checks whether the file exists.
1.1191 +** With SQLITE_ACCESS_READWRITE, the xAccess method
1.1192 +** checks whether the named directory is both readable and writable
1.1193 +** (in other words, if files can be added, removed, and renamed within
1.1194 +** the directory).
1.1195 +** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1.1196 +** [temp_store_directory pragma], though this could change in a future
1.1197 +** release of SQLite.
1.1198 +** With SQLITE_ACCESS_READ, the xAccess method
1.1199 +** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
1.1200 +** currently unused, though it might be used in a future release of
1.1201 +** SQLite.
1.1202 +*/
1.1203 +#define SQLITE_ACCESS_EXISTS 0
1.1204 +#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
1.1205 +#define SQLITE_ACCESS_READ 2 /* Unused */
1.1206 +
1.1207 +/*
1.1208 +** CAPI3REF: Flags for the xShmLock VFS method
1.1209 +**
1.1210 +** These integer constants define the various locking operations
1.1211 +** allowed by the xShmLock method of [sqlite3_io_methods]. The
1.1212 +** following are the only legal combinations of flags to the
1.1213 +** xShmLock method:
1.1214 +**
1.1215 +** <ul>
1.1216 +** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1.1217 +** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1.1218 +** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1.1219 +** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1.1220 +** </ul>
1.1221 +**
1.1222 +** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1.1223 +** was given no the corresponding lock.
1.1224 +**
1.1225 +** The xShmLock method can transition between unlocked and SHARED or
1.1226 +** between unlocked and EXCLUSIVE. It cannot transition between SHARED
1.1227 +** and EXCLUSIVE.
1.1228 +*/
1.1229 +#define SQLITE_SHM_UNLOCK 1
1.1230 +#define SQLITE_SHM_LOCK 2
1.1231 +#define SQLITE_SHM_SHARED 4
1.1232 +#define SQLITE_SHM_EXCLUSIVE 8
1.1233 +
1.1234 +/*
1.1235 +** CAPI3REF: Maximum xShmLock index
1.1236 +**
1.1237 +** The xShmLock method on [sqlite3_io_methods] may use values
1.1238 +** between 0 and this upper bound as its "offset" argument.
1.1239 +** The SQLite core will never attempt to acquire or release a
1.1240 +** lock outside of this range
1.1241 +*/
1.1242 +#define SQLITE_SHM_NLOCK 8
1.1243 +
1.1244 +
1.1245 +/*
1.1246 +** CAPI3REF: Initialize The SQLite Library
1.1247 +**
1.1248 +** ^The sqlite3_initialize() routine initializes the
1.1249 +** SQLite library. ^The sqlite3_shutdown() routine
1.1250 +** deallocates any resources that were allocated by sqlite3_initialize().
1.1251 +** These routines are designed to aid in process initialization and
1.1252 +** shutdown on embedded systems. Workstation applications using
1.1253 +** SQLite normally do not need to invoke either of these routines.
1.1254 +**
1.1255 +** A call to sqlite3_initialize() is an "effective" call if it is
1.1256 +** the first time sqlite3_initialize() is invoked during the lifetime of
1.1257 +** the process, or if it is the first time sqlite3_initialize() is invoked
1.1258 +** following a call to sqlite3_shutdown(). ^(Only an effective call
1.1259 +** of sqlite3_initialize() does any initialization. All other calls
1.1260 +** are harmless no-ops.)^
1.1261 +**
1.1262 +** A call to sqlite3_shutdown() is an "effective" call if it is the first
1.1263 +** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
1.1264 +** an effective call to sqlite3_shutdown() does any deinitialization.
1.1265 +** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1.1266 +**
1.1267 +** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1.1268 +** is not. The sqlite3_shutdown() interface must only be called from a
1.1269 +** single thread. All open [database connections] must be closed and all
1.1270 +** other SQLite resources must be deallocated prior to invoking
1.1271 +** sqlite3_shutdown().
1.1272 +**
1.1273 +** Among other things, ^sqlite3_initialize() will invoke
1.1274 +** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
1.1275 +** will invoke sqlite3_os_end().
1.1276 +**
1.1277 +** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1.1278 +** ^If for some reason, sqlite3_initialize() is unable to initialize
1.1279 +** the library (perhaps it is unable to allocate a needed resource such
1.1280 +** as a mutex) it returns an [error code] other than [SQLITE_OK].
1.1281 +**
1.1282 +** ^The sqlite3_initialize() routine is called internally by many other
1.1283 +** SQLite interfaces so that an application usually does not need to
1.1284 +** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
1.1285 +** calls sqlite3_initialize() so the SQLite library will be automatically
1.1286 +** initialized when [sqlite3_open()] is called if it has not be initialized
1.1287 +** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1.1288 +** compile-time option, then the automatic calls to sqlite3_initialize()
1.1289 +** are omitted and the application must call sqlite3_initialize() directly
1.1290 +** prior to using any other SQLite interface. For maximum portability,
1.1291 +** it is recommended that applications always invoke sqlite3_initialize()
1.1292 +** directly prior to using any other SQLite interface. Future releases
1.1293 +** of SQLite may require this. In other words, the behavior exhibited
1.1294 +** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1.1295 +** default behavior in some future release of SQLite.
1.1296 +**
1.1297 +** The sqlite3_os_init() routine does operating-system specific
1.1298 +** initialization of the SQLite library. The sqlite3_os_end()
1.1299 +** routine undoes the effect of sqlite3_os_init(). Typical tasks
1.1300 +** performed by these routines include allocation or deallocation
1.1301 +** of static resources, initialization of global variables,
1.1302 +** setting up a default [sqlite3_vfs] module, or setting up
1.1303 +** a default configuration using [sqlite3_config()].
1.1304 +**
1.1305 +** The application should never invoke either sqlite3_os_init()
1.1306 +** or sqlite3_os_end() directly. The application should only invoke
1.1307 +** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
1.1308 +** interface is called automatically by sqlite3_initialize() and
1.1309 +** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
1.1310 +** implementations for sqlite3_os_init() and sqlite3_os_end()
1.1311 +** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1.1312 +** When [custom builds | built for other platforms]
1.1313 +** (using the [SQLITE_OS_OTHER=1] compile-time
1.1314 +** option) the application must supply a suitable implementation for
1.1315 +** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1.1316 +** implementation of sqlite3_os_init() or sqlite3_os_end()
1.1317 +** must return [SQLITE_OK] on success and some other [error code] upon
1.1318 +** failure.
1.1319 +*/
1.1320 +SQLITE_API int sqlite3_initialize(void);
1.1321 +SQLITE_API int sqlite3_shutdown(void);
1.1322 +SQLITE_API int sqlite3_os_init(void);
1.1323 +SQLITE_API int sqlite3_os_end(void);
1.1324 +
1.1325 +/*
1.1326 +** CAPI3REF: Configuring The SQLite Library
1.1327 +**
1.1328 +** The sqlite3_config() interface is used to make global configuration
1.1329 +** changes to SQLite in order to tune SQLite to the specific needs of
1.1330 +** the application. The default configuration is recommended for most
1.1331 +** applications and so this routine is usually not necessary. It is
1.1332 +** provided to support rare applications with unusual needs.
1.1333 +**
1.1334 +** The sqlite3_config() interface is not threadsafe. The application
1.1335 +** must insure that no other SQLite interfaces are invoked by other
1.1336 +** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
1.1337 +** may only be invoked prior to library initialization using
1.1338 +** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1.1339 +** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1.1340 +** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1.1341 +** Note, however, that ^sqlite3_config() can be called as part of the
1.1342 +** implementation of an application-defined [sqlite3_os_init()].
1.1343 +**
1.1344 +** The first argument to sqlite3_config() is an integer
1.1345 +** [configuration option] that determines
1.1346 +** what property of SQLite is to be configured. Subsequent arguments
1.1347 +** vary depending on the [configuration option]
1.1348 +** in the first argument.
1.1349 +**
1.1350 +** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1.1351 +** ^If the option is unknown or SQLite is unable to set the option
1.1352 +** then this routine returns a non-zero [error code].
1.1353 +*/
1.1354 +SQLITE_API int sqlite3_config(int, ...);
1.1355 +
1.1356 +/*
1.1357 +** CAPI3REF: Configure database connections
1.1358 +**
1.1359 +** The sqlite3_db_config() interface is used to make configuration
1.1360 +** changes to a [database connection]. The interface is similar to
1.1361 +** [sqlite3_config()] except that the changes apply to a single
1.1362 +** [database connection] (specified in the first argument).
1.1363 +**
1.1364 +** The second argument to sqlite3_db_config(D,V,...) is the
1.1365 +** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1.1366 +** that indicates what aspect of the [database connection] is being configured.
1.1367 +** Subsequent arguments vary depending on the configuration verb.
1.1368 +**
1.1369 +** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1.1370 +** the call is considered successful.
1.1371 +*/
1.1372 +SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1.1373 +
1.1374 +/*
1.1375 +** CAPI3REF: Memory Allocation Routines
1.1376 +**
1.1377 +** An instance of this object defines the interface between SQLite
1.1378 +** and low-level memory allocation routines.
1.1379 +**
1.1380 +** This object is used in only one place in the SQLite interface.
1.1381 +** A pointer to an instance of this object is the argument to
1.1382 +** [sqlite3_config()] when the configuration option is
1.1383 +** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1.1384 +** By creating an instance of this object
1.1385 +** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1.1386 +** during configuration, an application can specify an alternative
1.1387 +** memory allocation subsystem for SQLite to use for all of its
1.1388 +** dynamic memory needs.
1.1389 +**
1.1390 +** Note that SQLite comes with several [built-in memory allocators]
1.1391 +** that are perfectly adequate for the overwhelming majority of applications
1.1392 +** and that this object is only useful to a tiny minority of applications
1.1393 +** with specialized memory allocation requirements. This object is
1.1394 +** also used during testing of SQLite in order to specify an alternative
1.1395 +** memory allocator that simulates memory out-of-memory conditions in
1.1396 +** order to verify that SQLite recovers gracefully from such
1.1397 +** conditions.
1.1398 +**
1.1399 +** The xMalloc, xRealloc, and xFree methods must work like the
1.1400 +** malloc(), realloc() and free() functions from the standard C library.
1.1401 +** ^SQLite guarantees that the second argument to
1.1402 +** xRealloc is always a value returned by a prior call to xRoundup.
1.1403 +**
1.1404 +** xSize should return the allocated size of a memory allocation
1.1405 +** previously obtained from xMalloc or xRealloc. The allocated size
1.1406 +** is always at least as big as the requested size but may be larger.
1.1407 +**
1.1408 +** The xRoundup method returns what would be the allocated size of
1.1409 +** a memory allocation given a particular requested size. Most memory
1.1410 +** allocators round up memory allocations at least to the next multiple
1.1411 +** of 8. Some allocators round up to a larger multiple or to a power of 2.
1.1412 +** Every memory allocation request coming in through [sqlite3_malloc()]
1.1413 +** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1.1414 +** that causes the corresponding memory allocation to fail.
1.1415 +**
1.1416 +** The xInit method initializes the memory allocator. For example,
1.1417 +** it might allocate any require mutexes or initialize internal data
1.1418 +** structures. The xShutdown method is invoked (indirectly) by
1.1419 +** [sqlite3_shutdown()] and should deallocate any resources acquired
1.1420 +** by xInit. The pAppData pointer is used as the only parameter to
1.1421 +** xInit and xShutdown.
1.1422 +**
1.1423 +** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1.1424 +** the xInit method, so the xInit method need not be threadsafe. The
1.1425 +** xShutdown method is only called from [sqlite3_shutdown()] so it does
1.1426 +** not need to be threadsafe either. For all other methods, SQLite
1.1427 +** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1.1428 +** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1.1429 +** it is by default) and so the methods are automatically serialized.
1.1430 +** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1.1431 +** methods must be threadsafe or else make their own arrangements for
1.1432 +** serialization.
1.1433 +**
1.1434 +** SQLite will never invoke xInit() more than once without an intervening
1.1435 +** call to xShutdown().
1.1436 +*/
1.1437 +typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1.1438 +struct sqlite3_mem_methods {
1.1439 + void *(*xMalloc)(int); /* Memory allocation function */
1.1440 + void (*xFree)(void*); /* Free a prior allocation */
1.1441 + void *(*xRealloc)(void*,int); /* Resize an allocation */
1.1442 + int (*xSize)(void*); /* Return the size of an allocation */
1.1443 + int (*xRoundup)(int); /* Round up request size to allocation size */
1.1444 + int (*xInit)(void*); /* Initialize the memory allocator */
1.1445 + void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1.1446 + void *pAppData; /* Argument to xInit() and xShutdown() */
1.1447 +};
1.1448 +
1.1449 +/*
1.1450 +** CAPI3REF: Configuration Options
1.1451 +** KEYWORDS: {configuration option}
1.1452 +**
1.1453 +** These constants are the available integer configuration options that
1.1454 +** can be passed as the first argument to the [sqlite3_config()] interface.
1.1455 +**
1.1456 +** New configuration options may be added in future releases of SQLite.
1.1457 +** Existing configuration options might be discontinued. Applications
1.1458 +** should check the return code from [sqlite3_config()] to make sure that
1.1459 +** the call worked. The [sqlite3_config()] interface will return a
1.1460 +** non-zero [error code] if a discontinued or unsupported configuration option
1.1461 +** is invoked.
1.1462 +**
1.1463 +** <dl>
1.1464 +** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1.1465 +** <dd>There are no arguments to this option. ^This option sets the
1.1466 +** [threading mode] to Single-thread. In other words, it disables
1.1467 +** all mutexing and puts SQLite into a mode where it can only be used
1.1468 +** by a single thread. ^If SQLite is compiled with
1.1469 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1470 +** it is not possible to change the [threading mode] from its default
1.1471 +** value of Single-thread and so [sqlite3_config()] will return
1.1472 +** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1.1473 +** configuration option.</dd>
1.1474 +**
1.1475 +** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1.1476 +** <dd>There are no arguments to this option. ^This option sets the
1.1477 +** [threading mode] to Multi-thread. In other words, it disables
1.1478 +** mutexing on [database connection] and [prepared statement] objects.
1.1479 +** The application is responsible for serializing access to
1.1480 +** [database connections] and [prepared statements]. But other mutexes
1.1481 +** are enabled so that SQLite will be safe to use in a multi-threaded
1.1482 +** environment as long as no two threads attempt to use the same
1.1483 +** [database connection] at the same time. ^If SQLite is compiled with
1.1484 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1485 +** it is not possible to set the Multi-thread [threading mode] and
1.1486 +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1.1487 +** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1.1488 +**
1.1489 +** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1.1490 +** <dd>There are no arguments to this option. ^This option sets the
1.1491 +** [threading mode] to Serialized. In other words, this option enables
1.1492 +** all mutexes including the recursive
1.1493 +** mutexes on [database connection] and [prepared statement] objects.
1.1494 +** In this mode (which is the default when SQLite is compiled with
1.1495 +** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1.1496 +** to [database connections] and [prepared statements] so that the
1.1497 +** application is free to use the same [database connection] or the
1.1498 +** same [prepared statement] in different threads at the same time.
1.1499 +** ^If SQLite is compiled with
1.1500 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1501 +** it is not possible to set the Serialized [threading mode] and
1.1502 +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1.1503 +** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1.1504 +**
1.1505 +** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1.1506 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1507 +** instance of the [sqlite3_mem_methods] structure. The argument specifies
1.1508 +** alternative low-level memory allocation routines to be used in place of
1.1509 +** the memory allocation routines built into SQLite.)^ ^SQLite makes
1.1510 +** its own private copy of the content of the [sqlite3_mem_methods] structure
1.1511 +** before the [sqlite3_config()] call returns.</dd>
1.1512 +**
1.1513 +** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1.1514 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1515 +** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
1.1516 +** structure is filled with the currently defined memory allocation routines.)^
1.1517 +** This option can be used to overload the default memory allocation
1.1518 +** routines with a wrapper that simulations memory allocation failure or
1.1519 +** tracks memory usage, for example. </dd>
1.1520 +**
1.1521 +** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1.1522 +** <dd> ^This option takes single argument of type int, interpreted as a
1.1523 +** boolean, which enables or disables the collection of memory allocation
1.1524 +** statistics. ^(When memory allocation statistics are disabled, the
1.1525 +** following SQLite interfaces become non-operational:
1.1526 +** <ul>
1.1527 +** <li> [sqlite3_memory_used()]
1.1528 +** <li> [sqlite3_memory_highwater()]
1.1529 +** <li> [sqlite3_soft_heap_limit64()]
1.1530 +** <li> [sqlite3_status()]
1.1531 +** </ul>)^
1.1532 +** ^Memory allocation statistics are enabled by default unless SQLite is
1.1533 +** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1.1534 +** allocation statistics are disabled by default.
1.1535 +** </dd>
1.1536 +**
1.1537 +** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1.1538 +** <dd> ^This option specifies a static memory buffer that SQLite can use for
1.1539 +** scratch memory. There are three arguments: A pointer an 8-byte
1.1540 +** aligned memory buffer from which the scratch allocations will be
1.1541 +** drawn, the size of each scratch allocation (sz),
1.1542 +** and the maximum number of scratch allocations (N). The sz
1.1543 +** argument must be a multiple of 16.
1.1544 +** The first argument must be a pointer to an 8-byte aligned buffer
1.1545 +** of at least sz*N bytes of memory.
1.1546 +** ^SQLite will use no more than two scratch buffers per thread. So
1.1547 +** N should be set to twice the expected maximum number of threads.
1.1548 +** ^SQLite will never require a scratch buffer that is more than 6
1.1549 +** times the database page size. ^If SQLite needs needs additional
1.1550 +** scratch memory beyond what is provided by this configuration option, then
1.1551 +** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
1.1552 +**
1.1553 +** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1.1554 +** <dd> ^This option specifies a static memory buffer that SQLite can use for
1.1555 +** the database page cache with the default page cache implementation.
1.1556 +** This configuration should not be used if an application-define page
1.1557 +** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
1.1558 +** There are three arguments to this option: A pointer to 8-byte aligned
1.1559 +** memory, the size of each page buffer (sz), and the number of pages (N).
1.1560 +** The sz argument should be the size of the largest database page
1.1561 +** (a power of two between 512 and 32768) plus a little extra for each
1.1562 +** page header. ^The page header size is 20 to 40 bytes depending on
1.1563 +** the host architecture. ^It is harmless, apart from the wasted memory,
1.1564 +** to make sz a little too large. The first
1.1565 +** argument should point to an allocation of at least sz*N bytes of memory.
1.1566 +** ^SQLite will use the memory provided by the first argument to satisfy its
1.1567 +** memory needs for the first N pages that it adds to cache. ^If additional
1.1568 +** page cache memory is needed beyond what is provided by this option, then
1.1569 +** SQLite goes to [sqlite3_malloc()] for the additional storage space.
1.1570 +** The pointer in the first argument must
1.1571 +** be aligned to an 8-byte boundary or subsequent behavior of SQLite
1.1572 +** will be undefined.</dd>
1.1573 +**
1.1574 +** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1.1575 +** <dd> ^This option specifies a static memory buffer that SQLite will use
1.1576 +** for all of its dynamic memory allocation needs beyond those provided
1.1577 +** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
1.1578 +** There are three arguments: An 8-byte aligned pointer to the memory,
1.1579 +** the number of bytes in the memory buffer, and the minimum allocation size.
1.1580 +** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1.1581 +** to using its default memory allocator (the system malloc() implementation),
1.1582 +** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
1.1583 +** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1.1584 +** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
1.1585 +** allocator is engaged to handle all of SQLites memory allocation needs.
1.1586 +** The first pointer (the memory pointer) must be aligned to an 8-byte
1.1587 +** boundary or subsequent behavior of SQLite will be undefined.
1.1588 +** The minimum allocation size is capped at 2**12. Reasonable values
1.1589 +** for the minimum allocation size are 2**5 through 2**8.</dd>
1.1590 +**
1.1591 +** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1.1592 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1593 +** instance of the [sqlite3_mutex_methods] structure. The argument specifies
1.1594 +** alternative low-level mutex routines to be used in place
1.1595 +** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
1.1596 +** content of the [sqlite3_mutex_methods] structure before the call to
1.1597 +** [sqlite3_config()] returns. ^If SQLite is compiled with
1.1598 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1599 +** the entire mutexing subsystem is omitted from the build and hence calls to
1.1600 +** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1.1601 +** return [SQLITE_ERROR].</dd>
1.1602 +**
1.1603 +** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1.1604 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1605 +** instance of the [sqlite3_mutex_methods] structure. The
1.1606 +** [sqlite3_mutex_methods]
1.1607 +** structure is filled with the currently defined mutex routines.)^
1.1608 +** This option can be used to overload the default mutex allocation
1.1609 +** routines with a wrapper used to track mutex usage for performance
1.1610 +** profiling or testing, for example. ^If SQLite is compiled with
1.1611 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1.1612 +** the entire mutexing subsystem is omitted from the build and hence calls to
1.1613 +** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1.1614 +** return [SQLITE_ERROR].</dd>
1.1615 +**
1.1616 +** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1.1617 +** <dd> ^(This option takes two arguments that determine the default
1.1618 +** memory allocation for the lookaside memory allocator on each
1.1619 +** [database connection]. The first argument is the
1.1620 +** size of each lookaside buffer slot and the second is the number of
1.1621 +** slots allocated to each database connection.)^ ^(This option sets the
1.1622 +** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1.1623 +** verb to [sqlite3_db_config()] can be used to change the lookaside
1.1624 +** configuration on individual connections.)^ </dd>
1.1625 +**
1.1626 +** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1.1627 +** <dd> ^(This option takes a single argument which is a pointer to
1.1628 +** an [sqlite3_pcache_methods2] object. This object specifies the interface
1.1629 +** to a custom page cache implementation.)^ ^SQLite makes a copy of the
1.1630 +** object and uses it for page cache memory allocations.</dd>
1.1631 +**
1.1632 +** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1.1633 +** <dd> ^(This option takes a single argument which is a pointer to an
1.1634 +** [sqlite3_pcache_methods2] object. SQLite copies of the current
1.1635 +** page cache implementation into that object.)^ </dd>
1.1636 +**
1.1637 +** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1.1638 +** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1.1639 +** global [error log].
1.1640 +** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1.1641 +** function with a call signature of void(*)(void*,int,const char*),
1.1642 +** and a pointer to void. ^If the function pointer is not NULL, it is
1.1643 +** invoked by [sqlite3_log()] to process each logging event. ^If the
1.1644 +** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1.1645 +** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1.1646 +** passed through as the first parameter to the application-defined logger
1.1647 +** function whenever that function is invoked. ^The second parameter to
1.1648 +** the logger function is a copy of the first parameter to the corresponding
1.1649 +** [sqlite3_log()] call and is intended to be a [result code] or an
1.1650 +** [extended result code]. ^The third parameter passed to the logger is
1.1651 +** log message after formatting via [sqlite3_snprintf()].
1.1652 +** The SQLite logging interface is not reentrant; the logger function
1.1653 +** supplied by the application must not invoke any SQLite interface.
1.1654 +** In a multi-threaded application, the application-defined logger
1.1655 +** function must be threadsafe. </dd>
1.1656 +**
1.1657 +** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1.1658 +** <dd>^(This option takes a single argument of type int. If non-zero, then
1.1659 +** URI handling is globally enabled. If the parameter is zero, then URI handling
1.1660 +** is globally disabled.)^ ^If URI handling is globally enabled, all filenames
1.1661 +** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
1.1662 +** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1.1663 +** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1.1664 +** connection is opened. ^If it is globally disabled, filenames are
1.1665 +** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1.1666 +** database connection is opened. ^(By default, URI handling is globally
1.1667 +** disabled. The default value may be changed by compiling with the
1.1668 +** [SQLITE_USE_URI] symbol defined.)^
1.1669 +**
1.1670 +** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1.1671 +** <dd>^This option takes a single integer argument which is interpreted as
1.1672 +** a boolean in order to enable or disable the use of covering indices for
1.1673 +** full table scans in the query optimizer. ^The default setting is determined
1.1674 +** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1.1675 +** if that compile-time option is omitted.
1.1676 +** The ability to disable the use of covering indices for full table scans
1.1677 +** is because some incorrectly coded legacy applications might malfunction
1.1678 +** when the optimization is enabled. Providing the ability to
1.1679 +** disable the optimization allows the older, buggy application code to work
1.1680 +** without change even with newer versions of SQLite.
1.1681 +**
1.1682 +** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1.1683 +** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1.1684 +** <dd> These options are obsolete and should not be used by new code.
1.1685 +** They are retained for backwards compatibility but are now no-ops.
1.1686 +** </dd>
1.1687 +**
1.1688 +** [[SQLITE_CONFIG_SQLLOG]]
1.1689 +** <dt>SQLITE_CONFIG_SQLLOG
1.1690 +** <dd>This option is only available if sqlite is compiled with the
1.1691 +** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1.1692 +** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1.1693 +** The second should be of type (void*). The callback is invoked by the library
1.1694 +** in three separate circumstances, identified by the value passed as the
1.1695 +** fourth parameter. If the fourth parameter is 0, then the database connection
1.1696 +** passed as the second argument has just been opened. The third argument
1.1697 +** points to a buffer containing the name of the main database file. If the
1.1698 +** fourth parameter is 1, then the SQL statement that the third parameter
1.1699 +** points to has just been executed. Or, if the fourth parameter is 2, then
1.1700 +** the connection being passed as the second parameter is being closed. The
1.1701 +** third parameter is passed NULL In this case. An example of using this
1.1702 +** configuration option can be seen in the "test_sqllog.c" source file in
1.1703 +** the canonical SQLite source tree.</dd>
1.1704 +**
1.1705 +** [[SQLITE_CONFIG_MMAP_SIZE]]
1.1706 +** <dt>SQLITE_CONFIG_MMAP_SIZE
1.1707 +** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
1.1708 +** that are the default mmap size limit (the default setting for
1.1709 +** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
1.1710 +** ^The default setting can be overridden by each database connection using
1.1711 +** either the [PRAGMA mmap_size] command, or by using the
1.1712 +** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
1.1713 +** cannot be changed at run-time. Nor may the maximum allowed mmap size
1.1714 +** exceed the compile-time maximum mmap size set by the
1.1715 +** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
1.1716 +** ^If either argument to this option is negative, then that argument is
1.1717 +** changed to its compile-time default.
1.1718 +**
1.1719 +** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
1.1720 +** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
1.1721 +** <dd>^This option is only available if SQLite is compiled for Windows
1.1722 +** with the [SQLITE_WIN32_MALLOC] pre-processor macro defined.
1.1723 +** SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
1.1724 +** that specifies the maximum size of the created heap.
1.1725 +** </dl>
1.1726 +*/
1.1727 +#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
1.1728 +#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
1.1729 +#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
1.1730 +#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
1.1731 +#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1.1732 +#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
1.1733 +#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
1.1734 +#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
1.1735 +#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
1.1736 +#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
1.1737 +#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
1.1738 +/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
1.1739 +#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
1.1740 +#define SQLITE_CONFIG_PCACHE 14 /* no-op */
1.1741 +#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
1.1742 +#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
1.1743 +#define SQLITE_CONFIG_URI 17 /* int */
1.1744 +#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
1.1745 +#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
1.1746 +#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
1.1747 +#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
1.1748 +#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
1.1749 +#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
1.1750 +
1.1751 +/*
1.1752 +** CAPI3REF: Database Connection Configuration Options
1.1753 +**
1.1754 +** These constants are the available integer configuration options that
1.1755 +** can be passed as the second argument to the [sqlite3_db_config()] interface.
1.1756 +**
1.1757 +** New configuration options may be added in future releases of SQLite.
1.1758 +** Existing configuration options might be discontinued. Applications
1.1759 +** should check the return code from [sqlite3_db_config()] to make sure that
1.1760 +** the call worked. ^The [sqlite3_db_config()] interface will return a
1.1761 +** non-zero [error code] if a discontinued or unsupported configuration option
1.1762 +** is invoked.
1.1763 +**
1.1764 +** <dl>
1.1765 +** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1.1766 +** <dd> ^This option takes three additional arguments that determine the
1.1767 +** [lookaside memory allocator] configuration for the [database connection].
1.1768 +** ^The first argument (the third parameter to [sqlite3_db_config()] is a
1.1769 +** pointer to a memory buffer to use for lookaside memory.
1.1770 +** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1.1771 +** may be NULL in which case SQLite will allocate the
1.1772 +** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1.1773 +** size of each lookaside buffer slot. ^The third argument is the number of
1.1774 +** slots. The size of the buffer in the first argument must be greater than
1.1775 +** or equal to the product of the second and third arguments. The buffer
1.1776 +** must be aligned to an 8-byte boundary. ^If the second argument to
1.1777 +** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1.1778 +** rounded down to the next smaller multiple of 8. ^(The lookaside memory
1.1779 +** configuration for a database connection can only be changed when that
1.1780 +** connection is not currently using lookaside memory, or in other words
1.1781 +** when the "current value" returned by
1.1782 +** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
1.1783 +** Any attempt to change the lookaside memory configuration when lookaside
1.1784 +** memory is in use leaves the configuration unchanged and returns
1.1785 +** [SQLITE_BUSY].)^</dd>
1.1786 +**
1.1787 +** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
1.1788 +** <dd> ^This option is used to enable or disable the enforcement of
1.1789 +** [foreign key constraints]. There should be two additional arguments.
1.1790 +** The first argument is an integer which is 0 to disable FK enforcement,
1.1791 +** positive to enable FK enforcement or negative to leave FK enforcement
1.1792 +** unchanged. The second parameter is a pointer to an integer into which
1.1793 +** is written 0 or 1 to indicate whether FK enforcement is off or on
1.1794 +** following this call. The second parameter may be a NULL pointer, in
1.1795 +** which case the FK enforcement setting is not reported back. </dd>
1.1796 +**
1.1797 +** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
1.1798 +** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
1.1799 +** There should be two additional arguments.
1.1800 +** The first argument is an integer which is 0 to disable triggers,
1.1801 +** positive to enable triggers or negative to leave the setting unchanged.
1.1802 +** The second parameter is a pointer to an integer into which
1.1803 +** is written 0 or 1 to indicate whether triggers are disabled or enabled
1.1804 +** following this call. The second parameter may be a NULL pointer, in
1.1805 +** which case the trigger setting is not reported back. </dd>
1.1806 +**
1.1807 +** </dl>
1.1808 +*/
1.1809 +#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
1.1810 +#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
1.1811 +#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
1.1812 +
1.1813 +
1.1814 +/*
1.1815 +** CAPI3REF: Enable Or Disable Extended Result Codes
1.1816 +**
1.1817 +** ^The sqlite3_extended_result_codes() routine enables or disables the
1.1818 +** [extended result codes] feature of SQLite. ^The extended result
1.1819 +** codes are disabled by default for historical compatibility.
1.1820 +*/
1.1821 +SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
1.1822 +
1.1823 +/*
1.1824 +** CAPI3REF: Last Insert Rowid
1.1825 +**
1.1826 +** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
1.1827 +** has a unique 64-bit signed
1.1828 +** integer key called the [ROWID | "rowid"]. ^The rowid is always available
1.1829 +** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
1.1830 +** names are not also used by explicitly declared columns. ^If
1.1831 +** the table has a column of type [INTEGER PRIMARY KEY] then that column
1.1832 +** is another alias for the rowid.
1.1833 +**
1.1834 +** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the
1.1835 +** most recent successful [INSERT] into a rowid table or [virtual table]
1.1836 +** on database connection D.
1.1837 +** ^Inserts into [WITHOUT ROWID] tables are not recorded.
1.1838 +** ^If no successful [INSERT]s into rowid tables
1.1839 +** have ever occurred on the database connection D,
1.1840 +** then sqlite3_last_insert_rowid(D) returns zero.
1.1841 +**
1.1842 +** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
1.1843 +** method, then this routine will return the [rowid] of the inserted
1.1844 +** row as long as the trigger or virtual table method is running.
1.1845 +** But once the trigger or virtual table method ends, the value returned
1.1846 +** by this routine reverts to what it was before the trigger or virtual
1.1847 +** table method began.)^
1.1848 +**
1.1849 +** ^An [INSERT] that fails due to a constraint violation is not a
1.1850 +** successful [INSERT] and does not change the value returned by this
1.1851 +** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
1.1852 +** and INSERT OR ABORT make no changes to the return value of this
1.1853 +** routine when their insertion fails. ^(When INSERT OR REPLACE
1.1854 +** encounters a constraint violation, it does not fail. The
1.1855 +** INSERT continues to completion after deleting rows that caused
1.1856 +** the constraint problem so INSERT OR REPLACE will always change
1.1857 +** the return value of this interface.)^
1.1858 +**
1.1859 +** ^For the purposes of this routine, an [INSERT] is considered to
1.1860 +** be successful even if it is subsequently rolled back.
1.1861 +**
1.1862 +** This function is accessible to SQL statements via the
1.1863 +** [last_insert_rowid() SQL function].
1.1864 +**
1.1865 +** If a separate thread performs a new [INSERT] on the same
1.1866 +** database connection while the [sqlite3_last_insert_rowid()]
1.1867 +** function is running and thus changes the last insert [rowid],
1.1868 +** then the value returned by [sqlite3_last_insert_rowid()] is
1.1869 +** unpredictable and might not equal either the old or the new
1.1870 +** last insert [rowid].
1.1871 +*/
1.1872 +SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
1.1873 +
1.1874 +/*
1.1875 +** CAPI3REF: Count The Number Of Rows Modified
1.1876 +**
1.1877 +** ^This function returns the number of database rows that were changed
1.1878 +** or inserted or deleted by the most recently completed SQL statement
1.1879 +** on the [database connection] specified by the first parameter.
1.1880 +** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
1.1881 +** or [DELETE] statement are counted. Auxiliary changes caused by
1.1882 +** triggers or [foreign key actions] are not counted.)^ Use the
1.1883 +** [sqlite3_total_changes()] function to find the total number of changes
1.1884 +** including changes caused by triggers and foreign key actions.
1.1885 +**
1.1886 +** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
1.1887 +** are not counted. Only real table changes are counted.
1.1888 +**
1.1889 +** ^(A "row change" is a change to a single row of a single table
1.1890 +** caused by an INSERT, DELETE, or UPDATE statement. Rows that
1.1891 +** are changed as side effects of [REPLACE] constraint resolution,
1.1892 +** rollback, ABORT processing, [DROP TABLE], or by any other
1.1893 +** mechanisms do not count as direct row changes.)^
1.1894 +**
1.1895 +** A "trigger context" is a scope of execution that begins and
1.1896 +** ends with the script of a [CREATE TRIGGER | trigger].
1.1897 +** Most SQL statements are
1.1898 +** evaluated outside of any trigger. This is the "top level"
1.1899 +** trigger context. If a trigger fires from the top level, a
1.1900 +** new trigger context is entered for the duration of that one
1.1901 +** trigger. Subtriggers create subcontexts for their duration.
1.1902 +**
1.1903 +** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
1.1904 +** not create a new trigger context.
1.1905 +**
1.1906 +** ^This function returns the number of direct row changes in the
1.1907 +** most recent INSERT, UPDATE, or DELETE statement within the same
1.1908 +** trigger context.
1.1909 +**
1.1910 +** ^Thus, when called from the top level, this function returns the
1.1911 +** number of changes in the most recent INSERT, UPDATE, or DELETE
1.1912 +** that also occurred at the top level. ^(Within the body of a trigger,
1.1913 +** the sqlite3_changes() interface can be called to find the number of
1.1914 +** changes in the most recently completed INSERT, UPDATE, or DELETE
1.1915 +** statement within the body of the same trigger.
1.1916 +** However, the number returned does not include changes
1.1917 +** caused by subtriggers since those have their own context.)^
1.1918 +**
1.1919 +** See also the [sqlite3_total_changes()] interface, the
1.1920 +** [count_changes pragma], and the [changes() SQL function].
1.1921 +**
1.1922 +** If a separate thread makes changes on the same database connection
1.1923 +** while [sqlite3_changes()] is running then the value returned
1.1924 +** is unpredictable and not meaningful.
1.1925 +*/
1.1926 +SQLITE_API int sqlite3_changes(sqlite3*);
1.1927 +
1.1928 +/*
1.1929 +** CAPI3REF: Total Number Of Rows Modified
1.1930 +**
1.1931 +** ^This function returns the number of row changes caused by [INSERT],
1.1932 +** [UPDATE] or [DELETE] statements since the [database connection] was opened.
1.1933 +** ^(The count returned by sqlite3_total_changes() includes all changes
1.1934 +** from all [CREATE TRIGGER | trigger] contexts and changes made by
1.1935 +** [foreign key actions]. However,
1.1936 +** the count does not include changes used to implement [REPLACE] constraints,
1.1937 +** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
1.1938 +** count does not include rows of views that fire an [INSTEAD OF trigger],
1.1939 +** though if the INSTEAD OF trigger makes changes of its own, those changes
1.1940 +** are counted.)^
1.1941 +** ^The sqlite3_total_changes() function counts the changes as soon as
1.1942 +** the statement that makes them is completed (when the statement handle
1.1943 +** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
1.1944 +**
1.1945 +** See also the [sqlite3_changes()] interface, the
1.1946 +** [count_changes pragma], and the [total_changes() SQL function].
1.1947 +**
1.1948 +** If a separate thread makes changes on the same database connection
1.1949 +** while [sqlite3_total_changes()] is running then the value
1.1950 +** returned is unpredictable and not meaningful.
1.1951 +*/
1.1952 +SQLITE_API int sqlite3_total_changes(sqlite3*);
1.1953 +
1.1954 +/*
1.1955 +** CAPI3REF: Interrupt A Long-Running Query
1.1956 +**
1.1957 +** ^This function causes any pending database operation to abort and
1.1958 +** return at its earliest opportunity. This routine is typically
1.1959 +** called in response to a user action such as pressing "Cancel"
1.1960 +** or Ctrl-C where the user wants a long query operation to halt
1.1961 +** immediately.
1.1962 +**
1.1963 +** ^It is safe to call this routine from a thread different from the
1.1964 +** thread that is currently running the database operation. But it
1.1965 +** is not safe to call this routine with a [database connection] that
1.1966 +** is closed or might close before sqlite3_interrupt() returns.
1.1967 +**
1.1968 +** ^If an SQL operation is very nearly finished at the time when
1.1969 +** sqlite3_interrupt() is called, then it might not have an opportunity
1.1970 +** to be interrupted and might continue to completion.
1.1971 +**
1.1972 +** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1.1973 +** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
1.1974 +** that is inside an explicit transaction, then the entire transaction
1.1975 +** will be rolled back automatically.
1.1976 +**
1.1977 +** ^The sqlite3_interrupt(D) call is in effect until all currently running
1.1978 +** SQL statements on [database connection] D complete. ^Any new SQL statements
1.1979 +** that are started after the sqlite3_interrupt() call and before the
1.1980 +** running statements reaches zero are interrupted as if they had been
1.1981 +** running prior to the sqlite3_interrupt() call. ^New SQL statements
1.1982 +** that are started after the running statement count reaches zero are
1.1983 +** not effected by the sqlite3_interrupt().
1.1984 +** ^A call to sqlite3_interrupt(D) that occurs when there are no running
1.1985 +** SQL statements is a no-op and has no effect on SQL statements
1.1986 +** that are started after the sqlite3_interrupt() call returns.
1.1987 +**
1.1988 +** If the database connection closes while [sqlite3_interrupt()]
1.1989 +** is running then bad things will likely happen.
1.1990 +*/
1.1991 +SQLITE_API void sqlite3_interrupt(sqlite3*);
1.1992 +
1.1993 +/*
1.1994 +** CAPI3REF: Determine If An SQL Statement Is Complete
1.1995 +**
1.1996 +** These routines are useful during command-line input to determine if the
1.1997 +** currently entered text seems to form a complete SQL statement or
1.1998 +** if additional input is needed before sending the text into
1.1999 +** SQLite for parsing. ^These routines return 1 if the input string
1.2000 +** appears to be a complete SQL statement. ^A statement is judged to be
1.2001 +** complete if it ends with a semicolon token and is not a prefix of a
1.2002 +** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
1.2003 +** string literals or quoted identifier names or comments are not
1.2004 +** independent tokens (they are part of the token in which they are
1.2005 +** embedded) and thus do not count as a statement terminator. ^Whitespace
1.2006 +** and comments that follow the final semicolon are ignored.
1.2007 +**
1.2008 +** ^These routines return 0 if the statement is incomplete. ^If a
1.2009 +** memory allocation fails, then SQLITE_NOMEM is returned.
1.2010 +**
1.2011 +** ^These routines do not parse the SQL statements thus
1.2012 +** will not detect syntactically incorrect SQL.
1.2013 +**
1.2014 +** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
1.2015 +** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
1.2016 +** automatically by sqlite3_complete16(). If that initialization fails,
1.2017 +** then the return value from sqlite3_complete16() will be non-zero
1.2018 +** regardless of whether or not the input SQL is complete.)^
1.2019 +**
1.2020 +** The input to [sqlite3_complete()] must be a zero-terminated
1.2021 +** UTF-8 string.
1.2022 +**
1.2023 +** The input to [sqlite3_complete16()] must be a zero-terminated
1.2024 +** UTF-16 string in native byte order.
1.2025 +*/
1.2026 +SQLITE_API int sqlite3_complete(const char *sql);
1.2027 +SQLITE_API int sqlite3_complete16(const void *sql);
1.2028 +
1.2029 +/*
1.2030 +** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
1.2031 +**
1.2032 +** ^This routine sets a callback function that might be invoked whenever
1.2033 +** an attempt is made to open a database table that another thread
1.2034 +** or process has locked.
1.2035 +**
1.2036 +** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
1.2037 +** is returned immediately upon encountering the lock. ^If the busy callback
1.2038 +** is not NULL, then the callback might be invoked with two arguments.
1.2039 +**
1.2040 +** ^The first argument to the busy handler is a copy of the void* pointer which
1.2041 +** is the third argument to sqlite3_busy_handler(). ^The second argument to
1.2042 +** the busy handler callback is the number of times that the busy handler has
1.2043 +** been invoked for this locking event. ^If the
1.2044 +** busy callback returns 0, then no additional attempts are made to
1.2045 +** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
1.2046 +** ^If the callback returns non-zero, then another attempt
1.2047 +** is made to open the database for reading and the cycle repeats.
1.2048 +**
1.2049 +** The presence of a busy handler does not guarantee that it will be invoked
1.2050 +** when there is lock contention. ^If SQLite determines that invoking the busy
1.2051 +** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1.2052 +** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
1.2053 +** Consider a scenario where one process is holding a read lock that
1.2054 +** it is trying to promote to a reserved lock and
1.2055 +** a second process is holding a reserved lock that it is trying
1.2056 +** to promote to an exclusive lock. The first process cannot proceed
1.2057 +** because it is blocked by the second and the second process cannot
1.2058 +** proceed because it is blocked by the first. If both processes
1.2059 +** invoke the busy handlers, neither will make any progress. Therefore,
1.2060 +** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
1.2061 +** will induce the first process to release its read lock and allow
1.2062 +** the second process to proceed.
1.2063 +**
1.2064 +** ^The default busy callback is NULL.
1.2065 +**
1.2066 +** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
1.2067 +** when SQLite is in the middle of a large transaction where all the
1.2068 +** changes will not fit into the in-memory cache. SQLite will
1.2069 +** already hold a RESERVED lock on the database file, but it needs
1.2070 +** to promote this lock to EXCLUSIVE so that it can spill cache
1.2071 +** pages into the database file without harm to concurrent
1.2072 +** readers. ^If it is unable to promote the lock, then the in-memory
1.2073 +** cache will be left in an inconsistent state and so the error
1.2074 +** code is promoted from the relatively benign [SQLITE_BUSY] to
1.2075 +** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
1.2076 +** forces an automatic rollback of the changes. See the
1.2077 +** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
1.2078 +** CorruptionFollowingBusyError</a> wiki page for a discussion of why
1.2079 +** this is important.
1.2080 +**
1.2081 +** ^(There can only be a single busy handler defined for each
1.2082 +** [database connection]. Setting a new busy handler clears any
1.2083 +** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
1.2084 +** will also set or clear the busy handler.
1.2085 +**
1.2086 +** The busy callback should not take any actions which modify the
1.2087 +** database connection that invoked the busy handler. Any such actions
1.2088 +** result in undefined behavior.
1.2089 +**
1.2090 +** A busy handler must not close the database connection
1.2091 +** or [prepared statement] that invoked the busy handler.
1.2092 +*/
1.2093 +SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
1.2094 +
1.2095 +/*
1.2096 +** CAPI3REF: Set A Busy Timeout
1.2097 +**
1.2098 +** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
1.2099 +** for a specified amount of time when a table is locked. ^The handler
1.2100 +** will sleep multiple times until at least "ms" milliseconds of sleeping
1.2101 +** have accumulated. ^After at least "ms" milliseconds of sleeping,
1.2102 +** the handler returns 0 which causes [sqlite3_step()] to return
1.2103 +** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
1.2104 +**
1.2105 +** ^Calling this routine with an argument less than or equal to zero
1.2106 +** turns off all busy handlers.
1.2107 +**
1.2108 +** ^(There can only be a single busy handler for a particular
1.2109 +** [database connection] any any given moment. If another busy handler
1.2110 +** was defined (using [sqlite3_busy_handler()]) prior to calling
1.2111 +** this routine, that other busy handler is cleared.)^
1.2112 +*/
1.2113 +SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
1.2114 +
1.2115 +/*
1.2116 +** CAPI3REF: Convenience Routines For Running Queries
1.2117 +**
1.2118 +** This is a legacy interface that is preserved for backwards compatibility.
1.2119 +** Use of this interface is not recommended.
1.2120 +**
1.2121 +** Definition: A <b>result table</b> is memory data structure created by the
1.2122 +** [sqlite3_get_table()] interface. A result table records the
1.2123 +** complete query results from one or more queries.
1.2124 +**
1.2125 +** The table conceptually has a number of rows and columns. But
1.2126 +** these numbers are not part of the result table itself. These
1.2127 +** numbers are obtained separately. Let N be the number of rows
1.2128 +** and M be the number of columns.
1.2129 +**
1.2130 +** A result table is an array of pointers to zero-terminated UTF-8 strings.
1.2131 +** There are (N+1)*M elements in the array. The first M pointers point
1.2132 +** to zero-terminated strings that contain the names of the columns.
1.2133 +** The remaining entries all point to query results. NULL values result
1.2134 +** in NULL pointers. All other values are in their UTF-8 zero-terminated
1.2135 +** string representation as returned by [sqlite3_column_text()].
1.2136 +**
1.2137 +** A result table might consist of one or more memory allocations.
1.2138 +** It is not safe to pass a result table directly to [sqlite3_free()].
1.2139 +** A result table should be deallocated using [sqlite3_free_table()].
1.2140 +**
1.2141 +** ^(As an example of the result table format, suppose a query result
1.2142 +** is as follows:
1.2143 +**
1.2144 +** <blockquote><pre>
1.2145 +** Name | Age
1.2146 +** -----------------------
1.2147 +** Alice | 43
1.2148 +** Bob | 28
1.2149 +** Cindy | 21
1.2150 +** </pre></blockquote>
1.2151 +**
1.2152 +** There are two column (M==2) and three rows (N==3). Thus the
1.2153 +** result table has 8 entries. Suppose the result table is stored
1.2154 +** in an array names azResult. Then azResult holds this content:
1.2155 +**
1.2156 +** <blockquote><pre>
1.2157 +** azResult[0] = "Name";
1.2158 +** azResult[1] = "Age";
1.2159 +** azResult[2] = "Alice";
1.2160 +** azResult[3] = "43";
1.2161 +** azResult[4] = "Bob";
1.2162 +** azResult[5] = "28";
1.2163 +** azResult[6] = "Cindy";
1.2164 +** azResult[7] = "21";
1.2165 +** </pre></blockquote>)^
1.2166 +**
1.2167 +** ^The sqlite3_get_table() function evaluates one or more
1.2168 +** semicolon-separated SQL statements in the zero-terminated UTF-8
1.2169 +** string of its 2nd parameter and returns a result table to the
1.2170 +** pointer given in its 3rd parameter.
1.2171 +**
1.2172 +** After the application has finished with the result from sqlite3_get_table(),
1.2173 +** it must pass the result table pointer to sqlite3_free_table() in order to
1.2174 +** release the memory that was malloced. Because of the way the
1.2175 +** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
1.2176 +** function must not try to call [sqlite3_free()] directly. Only
1.2177 +** [sqlite3_free_table()] is able to release the memory properly and safely.
1.2178 +**
1.2179 +** The sqlite3_get_table() interface is implemented as a wrapper around
1.2180 +** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
1.2181 +** to any internal data structures of SQLite. It uses only the public
1.2182 +** interface defined here. As a consequence, errors that occur in the
1.2183 +** wrapper layer outside of the internal [sqlite3_exec()] call are not
1.2184 +** reflected in subsequent calls to [sqlite3_errcode()] or
1.2185 +** [sqlite3_errmsg()].
1.2186 +*/
1.2187 +SQLITE_API int sqlite3_get_table(
1.2188 + sqlite3 *db, /* An open database */
1.2189 + const char *zSql, /* SQL to be evaluated */
1.2190 + char ***pazResult, /* Results of the query */
1.2191 + int *pnRow, /* Number of result rows written here */
1.2192 + int *pnColumn, /* Number of result columns written here */
1.2193 + char **pzErrmsg /* Error msg written here */
1.2194 +);
1.2195 +SQLITE_API void sqlite3_free_table(char **result);
1.2196 +
1.2197 +/*
1.2198 +** CAPI3REF: Formatted String Printing Functions
1.2199 +**
1.2200 +** These routines are work-alikes of the "printf()" family of functions
1.2201 +** from the standard C library.
1.2202 +**
1.2203 +** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
1.2204 +** results into memory obtained from [sqlite3_malloc()].
1.2205 +** The strings returned by these two routines should be
1.2206 +** released by [sqlite3_free()]. ^Both routines return a
1.2207 +** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1.2208 +** memory to hold the resulting string.
1.2209 +**
1.2210 +** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
1.2211 +** the standard C library. The result is written into the
1.2212 +** buffer supplied as the second parameter whose size is given by
1.2213 +** the first parameter. Note that the order of the
1.2214 +** first two parameters is reversed from snprintf().)^ This is an
1.2215 +** historical accident that cannot be fixed without breaking
1.2216 +** backwards compatibility. ^(Note also that sqlite3_snprintf()
1.2217 +** returns a pointer to its buffer instead of the number of
1.2218 +** characters actually written into the buffer.)^ We admit that
1.2219 +** the number of characters written would be a more useful return
1.2220 +** value but we cannot change the implementation of sqlite3_snprintf()
1.2221 +** now without breaking compatibility.
1.2222 +**
1.2223 +** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
1.2224 +** guarantees that the buffer is always zero-terminated. ^The first
1.2225 +** parameter "n" is the total size of the buffer, including space for
1.2226 +** the zero terminator. So the longest string that can be completely
1.2227 +** written will be n-1 characters.
1.2228 +**
1.2229 +** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
1.2230 +**
1.2231 +** These routines all implement some additional formatting
1.2232 +** options that are useful for constructing SQL statements.
1.2233 +** All of the usual printf() formatting options apply. In addition, there
1.2234 +** is are "%q", "%Q", and "%z" options.
1.2235 +**
1.2236 +** ^(The %q option works like %s in that it substitutes a nul-terminated
1.2237 +** string from the argument list. But %q also doubles every '\'' character.
1.2238 +** %q is designed for use inside a string literal.)^ By doubling each '\''
1.2239 +** character it escapes that character and allows it to be inserted into
1.2240 +** the string.
1.2241 +**
1.2242 +** For example, assume the string variable zText contains text as follows:
1.2243 +**
1.2244 +** <blockquote><pre>
1.2245 +** char *zText = "It's a happy day!";
1.2246 +** </pre></blockquote>
1.2247 +**
1.2248 +** One can use this text in an SQL statement as follows:
1.2249 +**
1.2250 +** <blockquote><pre>
1.2251 +** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1.2252 +** sqlite3_exec(db, zSQL, 0, 0, 0);
1.2253 +** sqlite3_free(zSQL);
1.2254 +** </pre></blockquote>
1.2255 +**
1.2256 +** Because the %q format string is used, the '\'' character in zText
1.2257 +** is escaped and the SQL generated is as follows:
1.2258 +**
1.2259 +** <blockquote><pre>
1.2260 +** INSERT INTO table1 VALUES('It''s a happy day!')
1.2261 +** </pre></blockquote>
1.2262 +**
1.2263 +** This is correct. Had we used %s instead of %q, the generated SQL
1.2264 +** would have looked like this:
1.2265 +**
1.2266 +** <blockquote><pre>
1.2267 +** INSERT INTO table1 VALUES('It's a happy day!');
1.2268 +** </pre></blockquote>
1.2269 +**
1.2270 +** This second example is an SQL syntax error. As a general rule you should
1.2271 +** always use %q instead of %s when inserting text into a string literal.
1.2272 +**
1.2273 +** ^(The %Q option works like %q except it also adds single quotes around
1.2274 +** the outside of the total string. Additionally, if the parameter in the
1.2275 +** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
1.2276 +** single quotes).)^ So, for example, one could say:
1.2277 +**
1.2278 +** <blockquote><pre>
1.2279 +** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1.2280 +** sqlite3_exec(db, zSQL, 0, 0, 0);
1.2281 +** sqlite3_free(zSQL);
1.2282 +** </pre></blockquote>
1.2283 +**
1.2284 +** The code above will render a correct SQL statement in the zSQL
1.2285 +** variable even if the zText variable is a NULL pointer.
1.2286 +**
1.2287 +** ^(The "%z" formatting option works like "%s" but with the
1.2288 +** addition that after the string has been read and copied into
1.2289 +** the result, [sqlite3_free()] is called on the input string.)^
1.2290 +*/
1.2291 +SQLITE_API char *sqlite3_mprintf(const char*,...);
1.2292 +SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
1.2293 +SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
1.2294 +SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
1.2295 +
1.2296 +/*
1.2297 +** CAPI3REF: Memory Allocation Subsystem
1.2298 +**
1.2299 +** The SQLite core uses these three routines for all of its own
1.2300 +** internal memory allocation needs. "Core" in the previous sentence
1.2301 +** does not include operating-system specific VFS implementation. The
1.2302 +** Windows VFS uses native malloc() and free() for some operations.
1.2303 +**
1.2304 +** ^The sqlite3_malloc() routine returns a pointer to a block
1.2305 +** of memory at least N bytes in length, where N is the parameter.
1.2306 +** ^If sqlite3_malloc() is unable to obtain sufficient free
1.2307 +** memory, it returns a NULL pointer. ^If the parameter N to
1.2308 +** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
1.2309 +** a NULL pointer.
1.2310 +**
1.2311 +** ^Calling sqlite3_free() with a pointer previously returned
1.2312 +** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
1.2313 +** that it might be reused. ^The sqlite3_free() routine is
1.2314 +** a no-op if is called with a NULL pointer. Passing a NULL pointer
1.2315 +** to sqlite3_free() is harmless. After being freed, memory
1.2316 +** should neither be read nor written. Even reading previously freed
1.2317 +** memory might result in a segmentation fault or other severe error.
1.2318 +** Memory corruption, a segmentation fault, or other severe error
1.2319 +** might result if sqlite3_free() is called with a non-NULL pointer that
1.2320 +** was not obtained from sqlite3_malloc() or sqlite3_realloc().
1.2321 +**
1.2322 +** ^(The sqlite3_realloc() interface attempts to resize a
1.2323 +** prior memory allocation to be at least N bytes, where N is the
1.2324 +** second parameter. The memory allocation to be resized is the first
1.2325 +** parameter.)^ ^ If the first parameter to sqlite3_realloc()
1.2326 +** is a NULL pointer then its behavior is identical to calling
1.2327 +** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
1.2328 +** ^If the second parameter to sqlite3_realloc() is zero or
1.2329 +** negative then the behavior is exactly the same as calling
1.2330 +** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
1.2331 +** ^sqlite3_realloc() returns a pointer to a memory allocation
1.2332 +** of at least N bytes in size or NULL if sufficient memory is unavailable.
1.2333 +** ^If M is the size of the prior allocation, then min(N,M) bytes
1.2334 +** of the prior allocation are copied into the beginning of buffer returned
1.2335 +** by sqlite3_realloc() and the prior allocation is freed.
1.2336 +** ^If sqlite3_realloc() returns NULL, then the prior allocation
1.2337 +** is not freed.
1.2338 +**
1.2339 +** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
1.2340 +** is always aligned to at least an 8 byte boundary, or to a
1.2341 +** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
1.2342 +** option is used.
1.2343 +**
1.2344 +** In SQLite version 3.5.0 and 3.5.1, it was possible to define
1.2345 +** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
1.2346 +** implementation of these routines to be omitted. That capability
1.2347 +** is no longer provided. Only built-in memory allocators can be used.
1.2348 +**
1.2349 +** Prior to SQLite version 3.7.10, the Windows OS interface layer called
1.2350 +** the system malloc() and free() directly when converting
1.2351 +** filenames between the UTF-8 encoding used by SQLite
1.2352 +** and whatever filename encoding is used by the particular Windows
1.2353 +** installation. Memory allocation errors were detected, but
1.2354 +** they were reported back as [SQLITE_CANTOPEN] or
1.2355 +** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
1.2356 +**
1.2357 +** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
1.2358 +** must be either NULL or else pointers obtained from a prior
1.2359 +** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
1.2360 +** not yet been released.
1.2361 +**
1.2362 +** The application must not read or write any part of
1.2363 +** a block of memory after it has been released using
1.2364 +** [sqlite3_free()] or [sqlite3_realloc()].
1.2365 +*/
1.2366 +SQLITE_API void *sqlite3_malloc(int);
1.2367 +SQLITE_API void *sqlite3_realloc(void*, int);
1.2368 +SQLITE_API void sqlite3_free(void*);
1.2369 +
1.2370 +/*
1.2371 +** CAPI3REF: Memory Allocator Statistics
1.2372 +**
1.2373 +** SQLite provides these two interfaces for reporting on the status
1.2374 +** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
1.2375 +** routines, which form the built-in memory allocation subsystem.
1.2376 +**
1.2377 +** ^The [sqlite3_memory_used()] routine returns the number of bytes
1.2378 +** of memory currently outstanding (malloced but not freed).
1.2379 +** ^The [sqlite3_memory_highwater()] routine returns the maximum
1.2380 +** value of [sqlite3_memory_used()] since the high-water mark
1.2381 +** was last reset. ^The values returned by [sqlite3_memory_used()] and
1.2382 +** [sqlite3_memory_highwater()] include any overhead
1.2383 +** added by SQLite in its implementation of [sqlite3_malloc()],
1.2384 +** but not overhead added by the any underlying system library
1.2385 +** routines that [sqlite3_malloc()] may call.
1.2386 +**
1.2387 +** ^The memory high-water mark is reset to the current value of
1.2388 +** [sqlite3_memory_used()] if and only if the parameter to
1.2389 +** [sqlite3_memory_highwater()] is true. ^The value returned
1.2390 +** by [sqlite3_memory_highwater(1)] is the high-water mark
1.2391 +** prior to the reset.
1.2392 +*/
1.2393 +SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
1.2394 +SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
1.2395 +
1.2396 +/*
1.2397 +** CAPI3REF: Pseudo-Random Number Generator
1.2398 +**
1.2399 +** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
1.2400 +** select random [ROWID | ROWIDs] when inserting new records into a table that
1.2401 +** already uses the largest possible [ROWID]. The PRNG is also used for
1.2402 +** the build-in random() and randomblob() SQL functions. This interface allows
1.2403 +** applications to access the same PRNG for other purposes.
1.2404 +**
1.2405 +** ^A call to this routine stores N bytes of randomness into buffer P.
1.2406 +** ^If N is less than one, then P can be a NULL pointer.
1.2407 +**
1.2408 +** ^If this routine has not been previously called or if the previous
1.2409 +** call had N less than one, then the PRNG is seeded using randomness
1.2410 +** obtained from the xRandomness method of the default [sqlite3_vfs] object.
1.2411 +** ^If the previous call to this routine had an N of 1 or more then
1.2412 +** the pseudo-randomness is generated
1.2413 +** internally and without recourse to the [sqlite3_vfs] xRandomness
1.2414 +** method.
1.2415 +*/
1.2416 +SQLITE_API void sqlite3_randomness(int N, void *P);
1.2417 +
1.2418 +/*
1.2419 +** CAPI3REF: Compile-Time Authorization Callbacks
1.2420 +**
1.2421 +** ^This routine registers an authorizer callback with a particular
1.2422 +** [database connection], supplied in the first argument.
1.2423 +** ^The authorizer callback is invoked as SQL statements are being compiled
1.2424 +** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
1.2425 +** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
1.2426 +** points during the compilation process, as logic is being created
1.2427 +** to perform various actions, the authorizer callback is invoked to
1.2428 +** see if those actions are allowed. ^The authorizer callback should
1.2429 +** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
1.2430 +** specific action but allow the SQL statement to continue to be
1.2431 +** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
1.2432 +** rejected with an error. ^If the authorizer callback returns
1.2433 +** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
1.2434 +** then the [sqlite3_prepare_v2()] or equivalent call that triggered
1.2435 +** the authorizer will fail with an error message.
1.2436 +**
1.2437 +** When the callback returns [SQLITE_OK], that means the operation
1.2438 +** requested is ok. ^When the callback returns [SQLITE_DENY], the
1.2439 +** [sqlite3_prepare_v2()] or equivalent call that triggered the
1.2440 +** authorizer will fail with an error message explaining that
1.2441 +** access is denied.
1.2442 +**
1.2443 +** ^The first parameter to the authorizer callback is a copy of the third
1.2444 +** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
1.2445 +** to the callback is an integer [SQLITE_COPY | action code] that specifies
1.2446 +** the particular action to be authorized. ^The third through sixth parameters
1.2447 +** to the callback are zero-terminated strings that contain additional
1.2448 +** details about the action to be authorized.
1.2449 +**
1.2450 +** ^If the action code is [SQLITE_READ]
1.2451 +** and the callback returns [SQLITE_IGNORE] then the
1.2452 +** [prepared statement] statement is constructed to substitute
1.2453 +** a NULL value in place of the table column that would have
1.2454 +** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
1.2455 +** return can be used to deny an untrusted user access to individual
1.2456 +** columns of a table.
1.2457 +** ^If the action code is [SQLITE_DELETE] and the callback returns
1.2458 +** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
1.2459 +** [truncate optimization] is disabled and all rows are deleted individually.
1.2460 +**
1.2461 +** An authorizer is used when [sqlite3_prepare | preparing]
1.2462 +** SQL statements from an untrusted source, to ensure that the SQL statements
1.2463 +** do not try to access data they are not allowed to see, or that they do not
1.2464 +** try to execute malicious statements that damage the database. For
1.2465 +** example, an application may allow a user to enter arbitrary
1.2466 +** SQL queries for evaluation by a database. But the application does
1.2467 +** not want the user to be able to make arbitrary changes to the
1.2468 +** database. An authorizer could then be put in place while the
1.2469 +** user-entered SQL is being [sqlite3_prepare | prepared] that
1.2470 +** disallows everything except [SELECT] statements.
1.2471 +**
1.2472 +** Applications that need to process SQL from untrusted sources
1.2473 +** might also consider lowering resource limits using [sqlite3_limit()]
1.2474 +** and limiting database size using the [max_page_count] [PRAGMA]
1.2475 +** in addition to using an authorizer.
1.2476 +**
1.2477 +** ^(Only a single authorizer can be in place on a database connection
1.2478 +** at a time. Each call to sqlite3_set_authorizer overrides the
1.2479 +** previous call.)^ ^Disable the authorizer by installing a NULL callback.
1.2480 +** The authorizer is disabled by default.
1.2481 +**
1.2482 +** The authorizer callback must not do anything that will modify
1.2483 +** the database connection that invoked the authorizer callback.
1.2484 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
1.2485 +** database connections for the meaning of "modify" in this paragraph.
1.2486 +**
1.2487 +** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
1.2488 +** statement might be re-prepared during [sqlite3_step()] due to a
1.2489 +** schema change. Hence, the application should ensure that the
1.2490 +** correct authorizer callback remains in place during the [sqlite3_step()].
1.2491 +**
1.2492 +** ^Note that the authorizer callback is invoked only during
1.2493 +** [sqlite3_prepare()] or its variants. Authorization is not
1.2494 +** performed during statement evaluation in [sqlite3_step()], unless
1.2495 +** as stated in the previous paragraph, sqlite3_step() invokes
1.2496 +** sqlite3_prepare_v2() to reprepare a statement after a schema change.
1.2497 +*/
1.2498 +SQLITE_API int sqlite3_set_authorizer(
1.2499 + sqlite3*,
1.2500 + int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
1.2501 + void *pUserData
1.2502 +);
1.2503 +
1.2504 +/*
1.2505 +** CAPI3REF: Authorizer Return Codes
1.2506 +**
1.2507 +** The [sqlite3_set_authorizer | authorizer callback function] must
1.2508 +** return either [SQLITE_OK] or one of these two constants in order
1.2509 +** to signal SQLite whether or not the action is permitted. See the
1.2510 +** [sqlite3_set_authorizer | authorizer documentation] for additional
1.2511 +** information.
1.2512 +**
1.2513 +** Note that SQLITE_IGNORE is also used as a [SQLITE_ROLLBACK | return code]
1.2514 +** from the [sqlite3_vtab_on_conflict()] interface.
1.2515 +*/
1.2516 +#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
1.2517 +#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
1.2518 +
1.2519 +/*
1.2520 +** CAPI3REF: Authorizer Action Codes
1.2521 +**
1.2522 +** The [sqlite3_set_authorizer()] interface registers a callback function
1.2523 +** that is invoked to authorize certain SQL statement actions. The
1.2524 +** second parameter to the callback is an integer code that specifies
1.2525 +** what action is being authorized. These are the integer action codes that
1.2526 +** the authorizer callback may be passed.
1.2527 +**
1.2528 +** These action code values signify what kind of operation is to be
1.2529 +** authorized. The 3rd and 4th parameters to the authorization
1.2530 +** callback function will be parameters or NULL depending on which of these
1.2531 +** codes is used as the second parameter. ^(The 5th parameter to the
1.2532 +** authorizer callback is the name of the database ("main", "temp",
1.2533 +** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
1.2534 +** is the name of the inner-most trigger or view that is responsible for
1.2535 +** the access attempt or NULL if this access attempt is directly from
1.2536 +** top-level SQL code.
1.2537 +*/
1.2538 +/******************************************* 3rd ************ 4th ***********/
1.2539 +#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
1.2540 +#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
1.2541 +#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
1.2542 +#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
1.2543 +#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
1.2544 +#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
1.2545 +#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
1.2546 +#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
1.2547 +#define SQLITE_DELETE 9 /* Table Name NULL */
1.2548 +#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
1.2549 +#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
1.2550 +#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
1.2551 +#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
1.2552 +#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
1.2553 +#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
1.2554 +#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
1.2555 +#define SQLITE_DROP_VIEW 17 /* View Name NULL */
1.2556 +#define SQLITE_INSERT 18 /* Table Name NULL */
1.2557 +#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
1.2558 +#define SQLITE_READ 20 /* Table Name Column Name */
1.2559 +#define SQLITE_SELECT 21 /* NULL NULL */
1.2560 +#define SQLITE_TRANSACTION 22 /* Operation NULL */
1.2561 +#define SQLITE_UPDATE 23 /* Table Name Column Name */
1.2562 +#define SQLITE_ATTACH 24 /* Filename NULL */
1.2563 +#define SQLITE_DETACH 25 /* Database Name NULL */
1.2564 +#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
1.2565 +#define SQLITE_REINDEX 27 /* Index Name NULL */
1.2566 +#define SQLITE_ANALYZE 28 /* Table Name NULL */
1.2567 +#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
1.2568 +#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
1.2569 +#define SQLITE_FUNCTION 31 /* NULL Function Name */
1.2570 +#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
1.2571 +#define SQLITE_COPY 0 /* No longer used */
1.2572 +#define SQLITE_RECURSIVE 33 /* NULL NULL */
1.2573 +
1.2574 +/*
1.2575 +** CAPI3REF: Tracing And Profiling Functions
1.2576 +**
1.2577 +** These routines register callback functions that can be used for
1.2578 +** tracing and profiling the execution of SQL statements.
1.2579 +**
1.2580 +** ^The callback function registered by sqlite3_trace() is invoked at
1.2581 +** various times when an SQL statement is being run by [sqlite3_step()].
1.2582 +** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
1.2583 +** SQL statement text as the statement first begins executing.
1.2584 +** ^(Additional sqlite3_trace() callbacks might occur
1.2585 +** as each triggered subprogram is entered. The callbacks for triggers
1.2586 +** contain a UTF-8 SQL comment that identifies the trigger.)^
1.2587 +**
1.2588 +** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
1.2589 +** the length of [bound parameter] expansion in the output of sqlite3_trace().
1.2590 +**
1.2591 +** ^The callback function registered by sqlite3_profile() is invoked
1.2592 +** as each SQL statement finishes. ^The profile callback contains
1.2593 +** the original statement text and an estimate of wall-clock time
1.2594 +** of how long that statement took to run. ^The profile callback
1.2595 +** time is in units of nanoseconds, however the current implementation
1.2596 +** is only capable of millisecond resolution so the six least significant
1.2597 +** digits in the time are meaningless. Future versions of SQLite
1.2598 +** might provide greater resolution on the profiler callback. The
1.2599 +** sqlite3_profile() function is considered experimental and is
1.2600 +** subject to change in future versions of SQLite.
1.2601 +*/
1.2602 +SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
1.2603 +SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
1.2604 + void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
1.2605 +
1.2606 +/*
1.2607 +** CAPI3REF: Query Progress Callbacks
1.2608 +**
1.2609 +** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
1.2610 +** function X to be invoked periodically during long running calls to
1.2611 +** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
1.2612 +** database connection D. An example use for this
1.2613 +** interface is to keep a GUI updated during a large query.
1.2614 +**
1.2615 +** ^The parameter P is passed through as the only parameter to the
1.2616 +** callback function X. ^The parameter N is the approximate number of
1.2617 +** [virtual machine instructions] that are evaluated between successive
1.2618 +** invocations of the callback X. ^If N is less than one then the progress
1.2619 +** handler is disabled.
1.2620 +**
1.2621 +** ^Only a single progress handler may be defined at one time per
1.2622 +** [database connection]; setting a new progress handler cancels the
1.2623 +** old one. ^Setting parameter X to NULL disables the progress handler.
1.2624 +** ^The progress handler is also disabled by setting N to a value less
1.2625 +** than 1.
1.2626 +**
1.2627 +** ^If the progress callback returns non-zero, the operation is
1.2628 +** interrupted. This feature can be used to implement a
1.2629 +** "Cancel" button on a GUI progress dialog box.
1.2630 +**
1.2631 +** The progress handler callback must not do anything that will modify
1.2632 +** the database connection that invoked the progress handler.
1.2633 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
1.2634 +** database connections for the meaning of "modify" in this paragraph.
1.2635 +**
1.2636 +*/
1.2637 +SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
1.2638 +
1.2639 +/*
1.2640 +** CAPI3REF: Opening A New Database Connection
1.2641 +**
1.2642 +** ^These routines open an SQLite database file as specified by the
1.2643 +** filename argument. ^The filename argument is interpreted as UTF-8 for
1.2644 +** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
1.2645 +** order for sqlite3_open16(). ^(A [database connection] handle is usually
1.2646 +** returned in *ppDb, even if an error occurs. The only exception is that
1.2647 +** if SQLite is unable to allocate memory to hold the [sqlite3] object,
1.2648 +** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
1.2649 +** object.)^ ^(If the database is opened (and/or created) successfully, then
1.2650 +** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
1.2651 +** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
1.2652 +** an English language description of the error following a failure of any
1.2653 +** of the sqlite3_open() routines.
1.2654 +**
1.2655 +** ^The default encoding for the database will be UTF-8 if
1.2656 +** sqlite3_open() or sqlite3_open_v2() is called and
1.2657 +** UTF-16 in the native byte order if sqlite3_open16() is used.
1.2658 +**
1.2659 +** Whether or not an error occurs when it is opened, resources
1.2660 +** associated with the [database connection] handle should be released by
1.2661 +** passing it to [sqlite3_close()] when it is no longer required.
1.2662 +**
1.2663 +** The sqlite3_open_v2() interface works like sqlite3_open()
1.2664 +** except that it accepts two additional parameters for additional control
1.2665 +** over the new database connection. ^(The flags parameter to
1.2666 +** sqlite3_open_v2() can take one of
1.2667 +** the following three values, optionally combined with the
1.2668 +** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
1.2669 +** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
1.2670 +**
1.2671 +** <dl>
1.2672 +** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
1.2673 +** <dd>The database is opened in read-only mode. If the database does not
1.2674 +** already exist, an error is returned.</dd>)^
1.2675 +**
1.2676 +** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
1.2677 +** <dd>The database is opened for reading and writing if possible, or reading
1.2678 +** only if the file is write protected by the operating system. In either
1.2679 +** case the database must already exist, otherwise an error is returned.</dd>)^
1.2680 +**
1.2681 +** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
1.2682 +** <dd>The database is opened for reading and writing, and is created if
1.2683 +** it does not already exist. This is the behavior that is always used for
1.2684 +** sqlite3_open() and sqlite3_open16().</dd>)^
1.2685 +** </dl>
1.2686 +**
1.2687 +** If the 3rd parameter to sqlite3_open_v2() is not one of the
1.2688 +** combinations shown above optionally combined with other
1.2689 +** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
1.2690 +** then the behavior is undefined.
1.2691 +**
1.2692 +** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
1.2693 +** opens in the multi-thread [threading mode] as long as the single-thread
1.2694 +** mode has not been set at compile-time or start-time. ^If the
1.2695 +** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
1.2696 +** in the serialized [threading mode] unless single-thread was
1.2697 +** previously selected at compile-time or start-time.
1.2698 +** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
1.2699 +** eligible to use [shared cache mode], regardless of whether or not shared
1.2700 +** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
1.2701 +** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
1.2702 +** participate in [shared cache mode] even if it is enabled.
1.2703 +**
1.2704 +** ^The fourth parameter to sqlite3_open_v2() is the name of the
1.2705 +** [sqlite3_vfs] object that defines the operating system interface that
1.2706 +** the new database connection should use. ^If the fourth parameter is
1.2707 +** a NULL pointer then the default [sqlite3_vfs] object is used.
1.2708 +**
1.2709 +** ^If the filename is ":memory:", then a private, temporary in-memory database
1.2710 +** is created for the connection. ^This in-memory database will vanish when
1.2711 +** the database connection is closed. Future versions of SQLite might
1.2712 +** make use of additional special filenames that begin with the ":" character.
1.2713 +** It is recommended that when a database filename actually does begin with
1.2714 +** a ":" character you should prefix the filename with a pathname such as
1.2715 +** "./" to avoid ambiguity.
1.2716 +**
1.2717 +** ^If the filename is an empty string, then a private, temporary
1.2718 +** on-disk database will be created. ^This private database will be
1.2719 +** automatically deleted as soon as the database connection is closed.
1.2720 +**
1.2721 +** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
1.2722 +**
1.2723 +** ^If [URI filename] interpretation is enabled, and the filename argument
1.2724 +** begins with "file:", then the filename is interpreted as a URI. ^URI
1.2725 +** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
1.2726 +** set in the fourth argument to sqlite3_open_v2(), or if it has
1.2727 +** been enabled globally using the [SQLITE_CONFIG_URI] option with the
1.2728 +** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
1.2729 +** As of SQLite version 3.7.7, URI filename interpretation is turned off
1.2730 +** by default, but future releases of SQLite might enable URI filename
1.2731 +** interpretation by default. See "[URI filenames]" for additional
1.2732 +** information.
1.2733 +**
1.2734 +** URI filenames are parsed according to RFC 3986. ^If the URI contains an
1.2735 +** authority, then it must be either an empty string or the string
1.2736 +** "localhost". ^If the authority is not an empty string or "localhost", an
1.2737 +** error is returned to the caller. ^The fragment component of a URI, if
1.2738 +** present, is ignored.
1.2739 +**
1.2740 +** ^SQLite uses the path component of the URI as the name of the disk file
1.2741 +** which contains the database. ^If the path begins with a '/' character,
1.2742 +** then it is interpreted as an absolute path. ^If the path does not begin
1.2743 +** with a '/' (meaning that the authority section is omitted from the URI)
1.2744 +** then the path is interpreted as a relative path.
1.2745 +** ^On windows, the first component of an absolute path
1.2746 +** is a drive specification (e.g. "C:").
1.2747 +**
1.2748 +** [[core URI query parameters]]
1.2749 +** The query component of a URI may contain parameters that are interpreted
1.2750 +** either by SQLite itself, or by a [VFS | custom VFS implementation].
1.2751 +** SQLite interprets the following three query parameters:
1.2752 +**
1.2753 +** <ul>
1.2754 +** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
1.2755 +** a VFS object that provides the operating system interface that should
1.2756 +** be used to access the database file on disk. ^If this option is set to
1.2757 +** an empty string the default VFS object is used. ^Specifying an unknown
1.2758 +** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
1.2759 +** present, then the VFS specified by the option takes precedence over
1.2760 +** the value passed as the fourth parameter to sqlite3_open_v2().
1.2761 +**
1.2762 +** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
1.2763 +** "rwc", or "memory". Attempting to set it to any other value is
1.2764 +** an error)^.
1.2765 +** ^If "ro" is specified, then the database is opened for read-only
1.2766 +** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
1.2767 +** third argument to sqlite3_open_v2(). ^If the mode option is set to
1.2768 +** "rw", then the database is opened for read-write (but not create)
1.2769 +** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
1.2770 +** been set. ^Value "rwc" is equivalent to setting both
1.2771 +** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
1.2772 +** set to "memory" then a pure [in-memory database] that never reads
1.2773 +** or writes from disk is used. ^It is an error to specify a value for
1.2774 +** the mode parameter that is less restrictive than that specified by
1.2775 +** the flags passed in the third parameter to sqlite3_open_v2().
1.2776 +**
1.2777 +** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
1.2778 +** "private". ^Setting it to "shared" is equivalent to setting the
1.2779 +** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
1.2780 +** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
1.2781 +** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
1.2782 +** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
1.2783 +** a URI filename, its value overrides any behavior requested by setting
1.2784 +** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
1.2785 +** </ul>
1.2786 +**
1.2787 +** ^Specifying an unknown parameter in the query component of a URI is not an
1.2788 +** error. Future versions of SQLite might understand additional query
1.2789 +** parameters. See "[query parameters with special meaning to SQLite]" for
1.2790 +** additional information.
1.2791 +**
1.2792 +** [[URI filename examples]] <h3>URI filename examples</h3>
1.2793 +**
1.2794 +** <table border="1" align=center cellpadding=5>
1.2795 +** <tr><th> URI filenames <th> Results
1.2796 +** <tr><td> file:data.db <td>
1.2797 +** Open the file "data.db" in the current directory.
1.2798 +** <tr><td> file:/home/fred/data.db<br>
1.2799 +** file:///home/fred/data.db <br>
1.2800 +** file://localhost/home/fred/data.db <br> <td>
1.2801 +** Open the database file "/home/fred/data.db".
1.2802 +** <tr><td> file://darkstar/home/fred/data.db <td>
1.2803 +** An error. "darkstar" is not a recognized authority.
1.2804 +** <tr><td style="white-space:nowrap">
1.2805 +** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
1.2806 +** <td> Windows only: Open the file "data.db" on fred's desktop on drive
1.2807 +** C:. Note that the %20 escaping in this example is not strictly
1.2808 +** necessary - space characters can be used literally
1.2809 +** in URI filenames.
1.2810 +** <tr><td> file:data.db?mode=ro&cache=private <td>
1.2811 +** Open file "data.db" in the current directory for read-only access.
1.2812 +** Regardless of whether or not shared-cache mode is enabled by
1.2813 +** default, use a private cache.
1.2814 +** <tr><td> file:/home/fred/data.db?vfs=unix-nolock <td>
1.2815 +** Open file "/home/fred/data.db". Use the special VFS "unix-nolock".
1.2816 +** <tr><td> file:data.db?mode=readonly <td>
1.2817 +** An error. "readonly" is not a valid option for the "mode" parameter.
1.2818 +** </table>
1.2819 +**
1.2820 +** ^URI hexadecimal escape sequences (%HH) are supported within the path and
1.2821 +** query components of a URI. A hexadecimal escape sequence consists of a
1.2822 +** percent sign - "%" - followed by exactly two hexadecimal digits
1.2823 +** specifying an octet value. ^Before the path or query components of a
1.2824 +** URI filename are interpreted, they are encoded using UTF-8 and all
1.2825 +** hexadecimal escape sequences replaced by a single byte containing the
1.2826 +** corresponding octet. If this process generates an invalid UTF-8 encoding,
1.2827 +** the results are undefined.
1.2828 +**
1.2829 +** <b>Note to Windows users:</b> The encoding used for the filename argument
1.2830 +** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
1.2831 +** codepage is currently defined. Filenames containing international
1.2832 +** characters must be converted to UTF-8 prior to passing them into
1.2833 +** sqlite3_open() or sqlite3_open_v2().
1.2834 +**
1.2835 +** <b>Note to Windows Runtime users:</b> The temporary directory must be set
1.2836 +** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
1.2837 +** features that require the use of temporary files may fail.
1.2838 +**
1.2839 +** See also: [sqlite3_temp_directory]
1.2840 +*/
1.2841 +SQLITE_API int sqlite3_open(
1.2842 + const char *filename, /* Database filename (UTF-8) */
1.2843 + sqlite3 **ppDb /* OUT: SQLite db handle */
1.2844 +);
1.2845 +SQLITE_API int sqlite3_open16(
1.2846 + const void *filename, /* Database filename (UTF-16) */
1.2847 + sqlite3 **ppDb /* OUT: SQLite db handle */
1.2848 +);
1.2849 +SQLITE_API int sqlite3_open_v2(
1.2850 + const char *filename, /* Database filename (UTF-8) */
1.2851 + sqlite3 **ppDb, /* OUT: SQLite db handle */
1.2852 + int flags, /* Flags */
1.2853 + const char *zVfs /* Name of VFS module to use */
1.2854 +);
1.2855 +
1.2856 +/*
1.2857 +** CAPI3REF: Obtain Values For URI Parameters
1.2858 +**
1.2859 +** These are utility routines, useful to VFS implementations, that check
1.2860 +** to see if a database file was a URI that contained a specific query
1.2861 +** parameter, and if so obtains the value of that query parameter.
1.2862 +**
1.2863 +** If F is the database filename pointer passed into the xOpen() method of
1.2864 +** a VFS implementation when the flags parameter to xOpen() has one or
1.2865 +** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
1.2866 +** P is the name of the query parameter, then
1.2867 +** sqlite3_uri_parameter(F,P) returns the value of the P
1.2868 +** parameter if it exists or a NULL pointer if P does not appear as a
1.2869 +** query parameter on F. If P is a query parameter of F
1.2870 +** has no explicit value, then sqlite3_uri_parameter(F,P) returns
1.2871 +** a pointer to an empty string.
1.2872 +**
1.2873 +** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
1.2874 +** parameter and returns true (1) or false (0) according to the value
1.2875 +** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
1.2876 +** value of query parameter P is one of "yes", "true", or "on" in any
1.2877 +** case or if the value begins with a non-zero number. The
1.2878 +** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
1.2879 +** query parameter P is one of "no", "false", or "off" in any case or
1.2880 +** if the value begins with a numeric zero. If P is not a query
1.2881 +** parameter on F or if the value of P is does not match any of the
1.2882 +** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
1.2883 +**
1.2884 +** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
1.2885 +** 64-bit signed integer and returns that integer, or D if P does not
1.2886 +** exist. If the value of P is something other than an integer, then
1.2887 +** zero is returned.
1.2888 +**
1.2889 +** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
1.2890 +** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
1.2891 +** is not a database file pathname pointer that SQLite passed into the xOpen
1.2892 +** VFS method, then the behavior of this routine is undefined and probably
1.2893 +** undesirable.
1.2894 +*/
1.2895 +SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
1.2896 +SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
1.2897 +SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
1.2898 +
1.2899 +
1.2900 +/*
1.2901 +** CAPI3REF: Error Codes And Messages
1.2902 +**
1.2903 +** ^The sqlite3_errcode() interface returns the numeric [result code] or
1.2904 +** [extended result code] for the most recent failed sqlite3_* API call
1.2905 +** associated with a [database connection]. If a prior API call failed
1.2906 +** but the most recent API call succeeded, the return value from
1.2907 +** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
1.2908 +** interface is the same except that it always returns the
1.2909 +** [extended result code] even when extended result codes are
1.2910 +** disabled.
1.2911 +**
1.2912 +** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
1.2913 +** text that describes the error, as either UTF-8 or UTF-16 respectively.
1.2914 +** ^(Memory to hold the error message string is managed internally.
1.2915 +** The application does not need to worry about freeing the result.
1.2916 +** However, the error string might be overwritten or deallocated by
1.2917 +** subsequent calls to other SQLite interface functions.)^
1.2918 +**
1.2919 +** ^The sqlite3_errstr() interface returns the English-language text
1.2920 +** that describes the [result code], as UTF-8.
1.2921 +** ^(Memory to hold the error message string is managed internally
1.2922 +** and must not be freed by the application)^.
1.2923 +**
1.2924 +** When the serialized [threading mode] is in use, it might be the
1.2925 +** case that a second error occurs on a separate thread in between
1.2926 +** the time of the first error and the call to these interfaces.
1.2927 +** When that happens, the second error will be reported since these
1.2928 +** interfaces always report the most recent result. To avoid
1.2929 +** this, each thread can obtain exclusive use of the [database connection] D
1.2930 +** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
1.2931 +** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
1.2932 +** all calls to the interfaces listed here are completed.
1.2933 +**
1.2934 +** If an interface fails with SQLITE_MISUSE, that means the interface
1.2935 +** was invoked incorrectly by the application. In that case, the
1.2936 +** error code and message may or may not be set.
1.2937 +*/
1.2938 +SQLITE_API int sqlite3_errcode(sqlite3 *db);
1.2939 +SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
1.2940 +SQLITE_API const char *sqlite3_errmsg(sqlite3*);
1.2941 +SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
1.2942 +SQLITE_API const char *sqlite3_errstr(int);
1.2943 +
1.2944 +/*
1.2945 +** CAPI3REF: SQL Statement Object
1.2946 +** KEYWORDS: {prepared statement} {prepared statements}
1.2947 +**
1.2948 +** An instance of this object represents a single SQL statement.
1.2949 +** This object is variously known as a "prepared statement" or a
1.2950 +** "compiled SQL statement" or simply as a "statement".
1.2951 +**
1.2952 +** The life of a statement object goes something like this:
1.2953 +**
1.2954 +** <ol>
1.2955 +** <li> Create the object using [sqlite3_prepare_v2()] or a related
1.2956 +** function.
1.2957 +** <li> Bind values to [host parameters] using the sqlite3_bind_*()
1.2958 +** interfaces.
1.2959 +** <li> Run the SQL by calling [sqlite3_step()] one or more times.
1.2960 +** <li> Reset the statement using [sqlite3_reset()] then go back
1.2961 +** to step 2. Do this zero or more times.
1.2962 +** <li> Destroy the object using [sqlite3_finalize()].
1.2963 +** </ol>
1.2964 +**
1.2965 +** Refer to documentation on individual methods above for additional
1.2966 +** information.
1.2967 +*/
1.2968 +typedef struct sqlite3_stmt sqlite3_stmt;
1.2969 +
1.2970 +/*
1.2971 +** CAPI3REF: Run-time Limits
1.2972 +**
1.2973 +** ^(This interface allows the size of various constructs to be limited
1.2974 +** on a connection by connection basis. The first parameter is the
1.2975 +** [database connection] whose limit is to be set or queried. The
1.2976 +** second parameter is one of the [limit categories] that define a
1.2977 +** class of constructs to be size limited. The third parameter is the
1.2978 +** new limit for that construct.)^
1.2979 +**
1.2980 +** ^If the new limit is a negative number, the limit is unchanged.
1.2981 +** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
1.2982 +** [limits | hard upper bound]
1.2983 +** set at compile-time by a C preprocessor macro called
1.2984 +** [limits | SQLITE_MAX_<i>NAME</i>].
1.2985 +** (The "_LIMIT_" in the name is changed to "_MAX_".))^
1.2986 +** ^Attempts to increase a limit above its hard upper bound are
1.2987 +** silently truncated to the hard upper bound.
1.2988 +**
1.2989 +** ^Regardless of whether or not the limit was changed, the
1.2990 +** [sqlite3_limit()] interface returns the prior value of the limit.
1.2991 +** ^Hence, to find the current value of a limit without changing it,
1.2992 +** simply invoke this interface with the third parameter set to -1.
1.2993 +**
1.2994 +** Run-time limits are intended for use in applications that manage
1.2995 +** both their own internal database and also databases that are controlled
1.2996 +** by untrusted external sources. An example application might be a
1.2997 +** web browser that has its own databases for storing history and
1.2998 +** separate databases controlled by JavaScript applications downloaded
1.2999 +** off the Internet. The internal databases can be given the
1.3000 +** large, default limits. Databases managed by external sources can
1.3001 +** be given much smaller limits designed to prevent a denial of service
1.3002 +** attack. Developers might also want to use the [sqlite3_set_authorizer()]
1.3003 +** interface to further control untrusted SQL. The size of the database
1.3004 +** created by an untrusted script can be contained using the
1.3005 +** [max_page_count] [PRAGMA].
1.3006 +**
1.3007 +** New run-time limit categories may be added in future releases.
1.3008 +*/
1.3009 +SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
1.3010 +
1.3011 +/*
1.3012 +** CAPI3REF: Run-Time Limit Categories
1.3013 +** KEYWORDS: {limit category} {*limit categories}
1.3014 +**
1.3015 +** These constants define various performance limits
1.3016 +** that can be lowered at run-time using [sqlite3_limit()].
1.3017 +** The synopsis of the meanings of the various limits is shown below.
1.3018 +** Additional information is available at [limits | Limits in SQLite].
1.3019 +**
1.3020 +** <dl>
1.3021 +** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
1.3022 +** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
1.3023 +**
1.3024 +** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
1.3025 +** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
1.3026 +**
1.3027 +** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
1.3028 +** <dd>The maximum number of columns in a table definition or in the
1.3029 +** result set of a [SELECT] or the maximum number of columns in an index
1.3030 +** or in an ORDER BY or GROUP BY clause.</dd>)^
1.3031 +**
1.3032 +** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
1.3033 +** <dd>The maximum depth of the parse tree on any expression.</dd>)^
1.3034 +**
1.3035 +** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
1.3036 +** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
1.3037 +**
1.3038 +** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
1.3039 +** <dd>The maximum number of instructions in a virtual machine program
1.3040 +** used to implement an SQL statement. This limit is not currently
1.3041 +** enforced, though that might be added in some future release of
1.3042 +** SQLite.</dd>)^
1.3043 +**
1.3044 +** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
1.3045 +** <dd>The maximum number of arguments on a function.</dd>)^
1.3046 +**
1.3047 +** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
1.3048 +** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
1.3049 +**
1.3050 +** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
1.3051 +** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
1.3052 +** <dd>The maximum length of the pattern argument to the [LIKE] or
1.3053 +** [GLOB] operators.</dd>)^
1.3054 +**
1.3055 +** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
1.3056 +** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
1.3057 +** <dd>The maximum index number of any [parameter] in an SQL statement.)^
1.3058 +**
1.3059 +** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
1.3060 +** <dd>The maximum depth of recursion for triggers.</dd>)^
1.3061 +** </dl>
1.3062 +*/
1.3063 +#define SQLITE_LIMIT_LENGTH 0
1.3064 +#define SQLITE_LIMIT_SQL_LENGTH 1
1.3065 +#define SQLITE_LIMIT_COLUMN 2
1.3066 +#define SQLITE_LIMIT_EXPR_DEPTH 3
1.3067 +#define SQLITE_LIMIT_COMPOUND_SELECT 4
1.3068 +#define SQLITE_LIMIT_VDBE_OP 5
1.3069 +#define SQLITE_LIMIT_FUNCTION_ARG 6
1.3070 +#define SQLITE_LIMIT_ATTACHED 7
1.3071 +#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
1.3072 +#define SQLITE_LIMIT_VARIABLE_NUMBER 9
1.3073 +#define SQLITE_LIMIT_TRIGGER_DEPTH 10
1.3074 +
1.3075 +/*
1.3076 +** CAPI3REF: Compiling An SQL Statement
1.3077 +** KEYWORDS: {SQL statement compiler}
1.3078 +**
1.3079 +** To execute an SQL query, it must first be compiled into a byte-code
1.3080 +** program using one of these routines.
1.3081 +**
1.3082 +** The first argument, "db", is a [database connection] obtained from a
1.3083 +** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
1.3084 +** [sqlite3_open16()]. The database connection must not have been closed.
1.3085 +**
1.3086 +** The second argument, "zSql", is the statement to be compiled, encoded
1.3087 +** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
1.3088 +** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
1.3089 +** use UTF-16.
1.3090 +**
1.3091 +** ^If the nByte argument is less than zero, then zSql is read up to the
1.3092 +** first zero terminator. ^If nByte is non-negative, then it is the maximum
1.3093 +** number of bytes read from zSql. ^When nByte is non-negative, the
1.3094 +** zSql string ends at either the first '\000' or '\u0000' character or
1.3095 +** the nByte-th byte, whichever comes first. If the caller knows
1.3096 +** that the supplied string is nul-terminated, then there is a small
1.3097 +** performance advantage to be gained by passing an nByte parameter that
1.3098 +** is equal to the number of bytes in the input string <i>including</i>
1.3099 +** the nul-terminator bytes as this saves SQLite from having to
1.3100 +** make a copy of the input string.
1.3101 +**
1.3102 +** ^If pzTail is not NULL then *pzTail is made to point to the first byte
1.3103 +** past the end of the first SQL statement in zSql. These routines only
1.3104 +** compile the first statement in zSql, so *pzTail is left pointing to
1.3105 +** what remains uncompiled.
1.3106 +**
1.3107 +** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
1.3108 +** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
1.3109 +** to NULL. ^If the input text contains no SQL (if the input is an empty
1.3110 +** string or a comment) then *ppStmt is set to NULL.
1.3111 +** The calling procedure is responsible for deleting the compiled
1.3112 +** SQL statement using [sqlite3_finalize()] after it has finished with it.
1.3113 +** ppStmt may not be NULL.
1.3114 +**
1.3115 +** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
1.3116 +** otherwise an [error code] is returned.
1.3117 +**
1.3118 +** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
1.3119 +** recommended for all new programs. The two older interfaces are retained
1.3120 +** for backwards compatibility, but their use is discouraged.
1.3121 +** ^In the "v2" interfaces, the prepared statement
1.3122 +** that is returned (the [sqlite3_stmt] object) contains a copy of the
1.3123 +** original SQL text. This causes the [sqlite3_step()] interface to
1.3124 +** behave differently in three ways:
1.3125 +**
1.3126 +** <ol>
1.3127 +** <li>
1.3128 +** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
1.3129 +** always used to do, [sqlite3_step()] will automatically recompile the SQL
1.3130 +** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
1.3131 +** retries will occur before sqlite3_step() gives up and returns an error.
1.3132 +** </li>
1.3133 +**
1.3134 +** <li>
1.3135 +** ^When an error occurs, [sqlite3_step()] will return one of the detailed
1.3136 +** [error codes] or [extended error codes]. ^The legacy behavior was that
1.3137 +** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
1.3138 +** and the application would have to make a second call to [sqlite3_reset()]
1.3139 +** in order to find the underlying cause of the problem. With the "v2" prepare
1.3140 +** interfaces, the underlying reason for the error is returned immediately.
1.3141 +** </li>
1.3142 +**
1.3143 +** <li>
1.3144 +** ^If the specific value bound to [parameter | host parameter] in the
1.3145 +** WHERE clause might influence the choice of query plan for a statement,
1.3146 +** then the statement will be automatically recompiled, as if there had been
1.3147 +** a schema change, on the first [sqlite3_step()] call following any change
1.3148 +** to the [sqlite3_bind_text | bindings] of that [parameter].
1.3149 +** ^The specific value of WHERE-clause [parameter] might influence the
1.3150 +** choice of query plan if the parameter is the left-hand side of a [LIKE]
1.3151 +** or [GLOB] operator or if the parameter is compared to an indexed column
1.3152 +** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
1.3153 +** </li>
1.3154 +** </ol>
1.3155 +*/
1.3156 +SQLITE_API int sqlite3_prepare(
1.3157 + sqlite3 *db, /* Database handle */
1.3158 + const char *zSql, /* SQL statement, UTF-8 encoded */
1.3159 + int nByte, /* Maximum length of zSql in bytes. */
1.3160 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3161 + const char **pzTail /* OUT: Pointer to unused portion of zSql */
1.3162 +);
1.3163 +SQLITE_API int sqlite3_prepare_v2(
1.3164 + sqlite3 *db, /* Database handle */
1.3165 + const char *zSql, /* SQL statement, UTF-8 encoded */
1.3166 + int nByte, /* Maximum length of zSql in bytes. */
1.3167 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3168 + const char **pzTail /* OUT: Pointer to unused portion of zSql */
1.3169 +);
1.3170 +SQLITE_API int sqlite3_prepare16(
1.3171 + sqlite3 *db, /* Database handle */
1.3172 + const void *zSql, /* SQL statement, UTF-16 encoded */
1.3173 + int nByte, /* Maximum length of zSql in bytes. */
1.3174 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3175 + const void **pzTail /* OUT: Pointer to unused portion of zSql */
1.3176 +);
1.3177 +SQLITE_API int sqlite3_prepare16_v2(
1.3178 + sqlite3 *db, /* Database handle */
1.3179 + const void *zSql, /* SQL statement, UTF-16 encoded */
1.3180 + int nByte, /* Maximum length of zSql in bytes. */
1.3181 + sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1.3182 + const void **pzTail /* OUT: Pointer to unused portion of zSql */
1.3183 +);
1.3184 +
1.3185 +/*
1.3186 +** CAPI3REF: Retrieving Statement SQL
1.3187 +**
1.3188 +** ^This interface can be used to retrieve a saved copy of the original
1.3189 +** SQL text used to create a [prepared statement] if that statement was
1.3190 +** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
1.3191 +*/
1.3192 +SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
1.3193 +
1.3194 +/*
1.3195 +** CAPI3REF: Determine If An SQL Statement Writes The Database
1.3196 +**
1.3197 +** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
1.3198 +** and only if the [prepared statement] X makes no direct changes to
1.3199 +** the content of the database file.
1.3200 +**
1.3201 +** Note that [application-defined SQL functions] or
1.3202 +** [virtual tables] might change the database indirectly as a side effect.
1.3203 +** ^(For example, if an application defines a function "eval()" that
1.3204 +** calls [sqlite3_exec()], then the following SQL statement would
1.3205 +** change the database file through side-effects:
1.3206 +**
1.3207 +** <blockquote><pre>
1.3208 +** SELECT eval('DELETE FROM t1') FROM t2;
1.3209 +** </pre></blockquote>
1.3210 +**
1.3211 +** But because the [SELECT] statement does not change the database file
1.3212 +** directly, sqlite3_stmt_readonly() would still return true.)^
1.3213 +**
1.3214 +** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
1.3215 +** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
1.3216 +** since the statements themselves do not actually modify the database but
1.3217 +** rather they control the timing of when other statements modify the
1.3218 +** database. ^The [ATTACH] and [DETACH] statements also cause
1.3219 +** sqlite3_stmt_readonly() to return true since, while those statements
1.3220 +** change the configuration of a database connection, they do not make
1.3221 +** changes to the content of the database files on disk.
1.3222 +*/
1.3223 +SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
1.3224 +
1.3225 +/*
1.3226 +** CAPI3REF: Determine If A Prepared Statement Has Been Reset
1.3227 +**
1.3228 +** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
1.3229 +** [prepared statement] S has been stepped at least once using
1.3230 +** [sqlite3_step(S)] but has not run to completion and/or has not
1.3231 +** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
1.3232 +** interface returns false if S is a NULL pointer. If S is not a
1.3233 +** NULL pointer and is not a pointer to a valid [prepared statement]
1.3234 +** object, then the behavior is undefined and probably undesirable.
1.3235 +**
1.3236 +** This interface can be used in combination [sqlite3_next_stmt()]
1.3237 +** to locate all prepared statements associated with a database
1.3238 +** connection that are in need of being reset. This can be used,
1.3239 +** for example, in diagnostic routines to search for prepared
1.3240 +** statements that are holding a transaction open.
1.3241 +*/
1.3242 +SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
1.3243 +
1.3244 +/*
1.3245 +** CAPI3REF: Dynamically Typed Value Object
1.3246 +** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
1.3247 +**
1.3248 +** SQLite uses the sqlite3_value object to represent all values
1.3249 +** that can be stored in a database table. SQLite uses dynamic typing
1.3250 +** for the values it stores. ^Values stored in sqlite3_value objects
1.3251 +** can be integers, floating point values, strings, BLOBs, or NULL.
1.3252 +**
1.3253 +** An sqlite3_value object may be either "protected" or "unprotected".
1.3254 +** Some interfaces require a protected sqlite3_value. Other interfaces
1.3255 +** will accept either a protected or an unprotected sqlite3_value.
1.3256 +** Every interface that accepts sqlite3_value arguments specifies
1.3257 +** whether or not it requires a protected sqlite3_value.
1.3258 +**
1.3259 +** The terms "protected" and "unprotected" refer to whether or not
1.3260 +** a mutex is held. An internal mutex is held for a protected
1.3261 +** sqlite3_value object but no mutex is held for an unprotected
1.3262 +** sqlite3_value object. If SQLite is compiled to be single-threaded
1.3263 +** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
1.3264 +** or if SQLite is run in one of reduced mutex modes
1.3265 +** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
1.3266 +** then there is no distinction between protected and unprotected
1.3267 +** sqlite3_value objects and they can be used interchangeably. However,
1.3268 +** for maximum code portability it is recommended that applications
1.3269 +** still make the distinction between protected and unprotected
1.3270 +** sqlite3_value objects even when not strictly required.
1.3271 +**
1.3272 +** ^The sqlite3_value objects that are passed as parameters into the
1.3273 +** implementation of [application-defined SQL functions] are protected.
1.3274 +** ^The sqlite3_value object returned by
1.3275 +** [sqlite3_column_value()] is unprotected.
1.3276 +** Unprotected sqlite3_value objects may only be used with
1.3277 +** [sqlite3_result_value()] and [sqlite3_bind_value()].
1.3278 +** The [sqlite3_value_blob | sqlite3_value_type()] family of
1.3279 +** interfaces require protected sqlite3_value objects.
1.3280 +*/
1.3281 +typedef struct Mem sqlite3_value;
1.3282 +
1.3283 +/*
1.3284 +** CAPI3REF: SQL Function Context Object
1.3285 +**
1.3286 +** The context in which an SQL function executes is stored in an
1.3287 +** sqlite3_context object. ^A pointer to an sqlite3_context object
1.3288 +** is always first parameter to [application-defined SQL functions].
1.3289 +** The application-defined SQL function implementation will pass this
1.3290 +** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
1.3291 +** [sqlite3_aggregate_context()], [sqlite3_user_data()],
1.3292 +** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
1.3293 +** and/or [sqlite3_set_auxdata()].
1.3294 +*/
1.3295 +typedef struct sqlite3_context sqlite3_context;
1.3296 +
1.3297 +/*
1.3298 +** CAPI3REF: Binding Values To Prepared Statements
1.3299 +** KEYWORDS: {host parameter} {host parameters} {host parameter name}
1.3300 +** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
1.3301 +**
1.3302 +** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
1.3303 +** literals may be replaced by a [parameter] that matches one of following
1.3304 +** templates:
1.3305 +**
1.3306 +** <ul>
1.3307 +** <li> ?
1.3308 +** <li> ?NNN
1.3309 +** <li> :VVV
1.3310 +** <li> @VVV
1.3311 +** <li> $VVV
1.3312 +** </ul>
1.3313 +**
1.3314 +** In the templates above, NNN represents an integer literal,
1.3315 +** and VVV represents an alphanumeric identifier.)^ ^The values of these
1.3316 +** parameters (also called "host parameter names" or "SQL parameters")
1.3317 +** can be set using the sqlite3_bind_*() routines defined here.
1.3318 +**
1.3319 +** ^The first argument to the sqlite3_bind_*() routines is always
1.3320 +** a pointer to the [sqlite3_stmt] object returned from
1.3321 +** [sqlite3_prepare_v2()] or its variants.
1.3322 +**
1.3323 +** ^The second argument is the index of the SQL parameter to be set.
1.3324 +** ^The leftmost SQL parameter has an index of 1. ^When the same named
1.3325 +** SQL parameter is used more than once, second and subsequent
1.3326 +** occurrences have the same index as the first occurrence.
1.3327 +** ^The index for named parameters can be looked up using the
1.3328 +** [sqlite3_bind_parameter_index()] API if desired. ^The index
1.3329 +** for "?NNN" parameters is the value of NNN.
1.3330 +** ^The NNN value must be between 1 and the [sqlite3_limit()]
1.3331 +** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
1.3332 +**
1.3333 +** ^The third argument is the value to bind to the parameter.
1.3334 +** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
1.3335 +** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
1.3336 +** is ignored and the end result is the same as sqlite3_bind_null().
1.3337 +**
1.3338 +** ^(In those routines that have a fourth argument, its value is the
1.3339 +** number of bytes in the parameter. To be clear: the value is the
1.3340 +** number of <u>bytes</u> in the value, not the number of characters.)^
1.3341 +** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
1.3342 +** is negative, then the length of the string is
1.3343 +** the number of bytes up to the first zero terminator.
1.3344 +** If the fourth parameter to sqlite3_bind_blob() is negative, then
1.3345 +** the behavior is undefined.
1.3346 +** If a non-negative fourth parameter is provided to sqlite3_bind_text()
1.3347 +** or sqlite3_bind_text16() then that parameter must be the byte offset
1.3348 +** where the NUL terminator would occur assuming the string were NUL
1.3349 +** terminated. If any NUL characters occur at byte offsets less than
1.3350 +** the value of the fourth parameter then the resulting string value will
1.3351 +** contain embedded NULs. The result of expressions involving strings
1.3352 +** with embedded NULs is undefined.
1.3353 +**
1.3354 +** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
1.3355 +** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
1.3356 +** string after SQLite has finished with it. ^The destructor is called
1.3357 +** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
1.3358 +** sqlite3_bind_text(), or sqlite3_bind_text16() fails.
1.3359 +** ^If the fifth argument is
1.3360 +** the special value [SQLITE_STATIC], then SQLite assumes that the
1.3361 +** information is in static, unmanaged space and does not need to be freed.
1.3362 +** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
1.3363 +** SQLite makes its own private copy of the data immediately, before
1.3364 +** the sqlite3_bind_*() routine returns.
1.3365 +**
1.3366 +** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
1.3367 +** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
1.3368 +** (just an integer to hold its size) while it is being processed.
1.3369 +** Zeroblobs are intended to serve as placeholders for BLOBs whose
1.3370 +** content is later written using
1.3371 +** [sqlite3_blob_open | incremental BLOB I/O] routines.
1.3372 +** ^A negative value for the zeroblob results in a zero-length BLOB.
1.3373 +**
1.3374 +** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
1.3375 +** for the [prepared statement] or with a prepared statement for which
1.3376 +** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
1.3377 +** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
1.3378 +** routine is passed a [prepared statement] that has been finalized, the
1.3379 +** result is undefined and probably harmful.
1.3380 +**
1.3381 +** ^Bindings are not cleared by the [sqlite3_reset()] routine.
1.3382 +** ^Unbound parameters are interpreted as NULL.
1.3383 +**
1.3384 +** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
1.3385 +** [error code] if anything goes wrong.
1.3386 +** ^[SQLITE_RANGE] is returned if the parameter
1.3387 +** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
1.3388 +**
1.3389 +** See also: [sqlite3_bind_parameter_count()],
1.3390 +** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
1.3391 +*/
1.3392 +SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
1.3393 +SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
1.3394 +SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
1.3395 +SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
1.3396 +SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
1.3397 +SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
1.3398 +SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
1.3399 +SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
1.3400 +SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
1.3401 +
1.3402 +/*
1.3403 +** CAPI3REF: Number Of SQL Parameters
1.3404 +**
1.3405 +** ^This routine can be used to find the number of [SQL parameters]
1.3406 +** in a [prepared statement]. SQL parameters are tokens of the
1.3407 +** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
1.3408 +** placeholders for values that are [sqlite3_bind_blob | bound]
1.3409 +** to the parameters at a later time.
1.3410 +**
1.3411 +** ^(This routine actually returns the index of the largest (rightmost)
1.3412 +** parameter. For all forms except ?NNN, this will correspond to the
1.3413 +** number of unique parameters. If parameters of the ?NNN form are used,
1.3414 +** there may be gaps in the list.)^
1.3415 +**
1.3416 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
1.3417 +** [sqlite3_bind_parameter_name()], and
1.3418 +** [sqlite3_bind_parameter_index()].
1.3419 +*/
1.3420 +SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
1.3421 +
1.3422 +/*
1.3423 +** CAPI3REF: Name Of A Host Parameter
1.3424 +**
1.3425 +** ^The sqlite3_bind_parameter_name(P,N) interface returns
1.3426 +** the name of the N-th [SQL parameter] in the [prepared statement] P.
1.3427 +** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
1.3428 +** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
1.3429 +** respectively.
1.3430 +** In other words, the initial ":" or "$" or "@" or "?"
1.3431 +** is included as part of the name.)^
1.3432 +** ^Parameters of the form "?" without a following integer have no name
1.3433 +** and are referred to as "nameless" or "anonymous parameters".
1.3434 +**
1.3435 +** ^The first host parameter has an index of 1, not 0.
1.3436 +**
1.3437 +** ^If the value N is out of range or if the N-th parameter is
1.3438 +** nameless, then NULL is returned. ^The returned string is
1.3439 +** always in UTF-8 encoding even if the named parameter was
1.3440 +** originally specified as UTF-16 in [sqlite3_prepare16()] or
1.3441 +** [sqlite3_prepare16_v2()].
1.3442 +**
1.3443 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
1.3444 +** [sqlite3_bind_parameter_count()], and
1.3445 +** [sqlite3_bind_parameter_index()].
1.3446 +*/
1.3447 +SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
1.3448 +
1.3449 +/*
1.3450 +** CAPI3REF: Index Of A Parameter With A Given Name
1.3451 +**
1.3452 +** ^Return the index of an SQL parameter given its name. ^The
1.3453 +** index value returned is suitable for use as the second
1.3454 +** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
1.3455 +** is returned if no matching parameter is found. ^The parameter
1.3456 +** name must be given in UTF-8 even if the original statement
1.3457 +** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
1.3458 +**
1.3459 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
1.3460 +** [sqlite3_bind_parameter_count()], and
1.3461 +** [sqlite3_bind_parameter_index()].
1.3462 +*/
1.3463 +SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
1.3464 +
1.3465 +/*
1.3466 +** CAPI3REF: Reset All Bindings On A Prepared Statement
1.3467 +**
1.3468 +** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
1.3469 +** the [sqlite3_bind_blob | bindings] on a [prepared statement].
1.3470 +** ^Use this routine to reset all host parameters to NULL.
1.3471 +*/
1.3472 +SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
1.3473 +
1.3474 +/*
1.3475 +** CAPI3REF: Number Of Columns In A Result Set
1.3476 +**
1.3477 +** ^Return the number of columns in the result set returned by the
1.3478 +** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
1.3479 +** statement that does not return data (for example an [UPDATE]).
1.3480 +**
1.3481 +** See also: [sqlite3_data_count()]
1.3482 +*/
1.3483 +SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
1.3484 +
1.3485 +/*
1.3486 +** CAPI3REF: Column Names In A Result Set
1.3487 +**
1.3488 +** ^These routines return the name assigned to a particular column
1.3489 +** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
1.3490 +** interface returns a pointer to a zero-terminated UTF-8 string
1.3491 +** and sqlite3_column_name16() returns a pointer to a zero-terminated
1.3492 +** UTF-16 string. ^The first parameter is the [prepared statement]
1.3493 +** that implements the [SELECT] statement. ^The second parameter is the
1.3494 +** column number. ^The leftmost column is number 0.
1.3495 +**
1.3496 +** ^The returned string pointer is valid until either the [prepared statement]
1.3497 +** is destroyed by [sqlite3_finalize()] or until the statement is automatically
1.3498 +** reprepared by the first call to [sqlite3_step()] for a particular run
1.3499 +** or until the next call to
1.3500 +** sqlite3_column_name() or sqlite3_column_name16() on the same column.
1.3501 +**
1.3502 +** ^If sqlite3_malloc() fails during the processing of either routine
1.3503 +** (for example during a conversion from UTF-8 to UTF-16) then a
1.3504 +** NULL pointer is returned.
1.3505 +**
1.3506 +** ^The name of a result column is the value of the "AS" clause for
1.3507 +** that column, if there is an AS clause. If there is no AS clause
1.3508 +** then the name of the column is unspecified and may change from
1.3509 +** one release of SQLite to the next.
1.3510 +*/
1.3511 +SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
1.3512 +SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
1.3513 +
1.3514 +/*
1.3515 +** CAPI3REF: Source Of Data In A Query Result
1.3516 +**
1.3517 +** ^These routines provide a means to determine the database, table, and
1.3518 +** table column that is the origin of a particular result column in
1.3519 +** [SELECT] statement.
1.3520 +** ^The name of the database or table or column can be returned as
1.3521 +** either a UTF-8 or UTF-16 string. ^The _database_ routines return
1.3522 +** the database name, the _table_ routines return the table name, and
1.3523 +** the origin_ routines return the column name.
1.3524 +** ^The returned string is valid until the [prepared statement] is destroyed
1.3525 +** using [sqlite3_finalize()] or until the statement is automatically
1.3526 +** reprepared by the first call to [sqlite3_step()] for a particular run
1.3527 +** or until the same information is requested
1.3528 +** again in a different encoding.
1.3529 +**
1.3530 +** ^The names returned are the original un-aliased names of the
1.3531 +** database, table, and column.
1.3532 +**
1.3533 +** ^The first argument to these interfaces is a [prepared statement].
1.3534 +** ^These functions return information about the Nth result column returned by
1.3535 +** the statement, where N is the second function argument.
1.3536 +** ^The left-most column is column 0 for these routines.
1.3537 +**
1.3538 +** ^If the Nth column returned by the statement is an expression or
1.3539 +** subquery and is not a column value, then all of these functions return
1.3540 +** NULL. ^These routine might also return NULL if a memory allocation error
1.3541 +** occurs. ^Otherwise, they return the name of the attached database, table,
1.3542 +** or column that query result column was extracted from.
1.3543 +**
1.3544 +** ^As with all other SQLite APIs, those whose names end with "16" return
1.3545 +** UTF-16 encoded strings and the other functions return UTF-8.
1.3546 +**
1.3547 +** ^These APIs are only available if the library was compiled with the
1.3548 +** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
1.3549 +**
1.3550 +** If two or more threads call one or more of these routines against the same
1.3551 +** prepared statement and column at the same time then the results are
1.3552 +** undefined.
1.3553 +**
1.3554 +** If two or more threads call one or more
1.3555 +** [sqlite3_column_database_name | column metadata interfaces]
1.3556 +** for the same [prepared statement] and result column
1.3557 +** at the same time then the results are undefined.
1.3558 +*/
1.3559 +SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
1.3560 +SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
1.3561 +SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
1.3562 +SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
1.3563 +SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
1.3564 +SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
1.3565 +
1.3566 +/*
1.3567 +** CAPI3REF: Declared Datatype Of A Query Result
1.3568 +**
1.3569 +** ^(The first parameter is a [prepared statement].
1.3570 +** If this statement is a [SELECT] statement and the Nth column of the
1.3571 +** returned result set of that [SELECT] is a table column (not an
1.3572 +** expression or subquery) then the declared type of the table
1.3573 +** column is returned.)^ ^If the Nth column of the result set is an
1.3574 +** expression or subquery, then a NULL pointer is returned.
1.3575 +** ^The returned string is always UTF-8 encoded.
1.3576 +**
1.3577 +** ^(For example, given the database schema:
1.3578 +**
1.3579 +** CREATE TABLE t1(c1 VARIANT);
1.3580 +**
1.3581 +** and the following statement to be compiled:
1.3582 +**
1.3583 +** SELECT c1 + 1, c1 FROM t1;
1.3584 +**
1.3585 +** this routine would return the string "VARIANT" for the second result
1.3586 +** column (i==1), and a NULL pointer for the first result column (i==0).)^
1.3587 +**
1.3588 +** ^SQLite uses dynamic run-time typing. ^So just because a column
1.3589 +** is declared to contain a particular type does not mean that the
1.3590 +** data stored in that column is of the declared type. SQLite is
1.3591 +** strongly typed, but the typing is dynamic not static. ^Type
1.3592 +** is associated with individual values, not with the containers
1.3593 +** used to hold those values.
1.3594 +*/
1.3595 +SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
1.3596 +SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
1.3597 +
1.3598 +/*
1.3599 +** CAPI3REF: Evaluate An SQL Statement
1.3600 +**
1.3601 +** After a [prepared statement] has been prepared using either
1.3602 +** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
1.3603 +** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
1.3604 +** must be called one or more times to evaluate the statement.
1.3605 +**
1.3606 +** The details of the behavior of the sqlite3_step() interface depend
1.3607 +** on whether the statement was prepared using the newer "v2" interface
1.3608 +** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
1.3609 +** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
1.3610 +** new "v2" interface is recommended for new applications but the legacy
1.3611 +** interface will continue to be supported.
1.3612 +**
1.3613 +** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
1.3614 +** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
1.3615 +** ^With the "v2" interface, any of the other [result codes] or
1.3616 +** [extended result codes] might be returned as well.
1.3617 +**
1.3618 +** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
1.3619 +** database locks it needs to do its job. ^If the statement is a [COMMIT]
1.3620 +** or occurs outside of an explicit transaction, then you can retry the
1.3621 +** statement. If the statement is not a [COMMIT] and occurs within an
1.3622 +** explicit transaction then you should rollback the transaction before
1.3623 +** continuing.
1.3624 +**
1.3625 +** ^[SQLITE_DONE] means that the statement has finished executing
1.3626 +** successfully. sqlite3_step() should not be called again on this virtual
1.3627 +** machine without first calling [sqlite3_reset()] to reset the virtual
1.3628 +** machine back to its initial state.
1.3629 +**
1.3630 +** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
1.3631 +** is returned each time a new row of data is ready for processing by the
1.3632 +** caller. The values may be accessed using the [column access functions].
1.3633 +** sqlite3_step() is called again to retrieve the next row of data.
1.3634 +**
1.3635 +** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
1.3636 +** violation) has occurred. sqlite3_step() should not be called again on
1.3637 +** the VM. More information may be found by calling [sqlite3_errmsg()].
1.3638 +** ^With the legacy interface, a more specific error code (for example,
1.3639 +** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
1.3640 +** can be obtained by calling [sqlite3_reset()] on the
1.3641 +** [prepared statement]. ^In the "v2" interface,
1.3642 +** the more specific error code is returned directly by sqlite3_step().
1.3643 +**
1.3644 +** [SQLITE_MISUSE] means that the this routine was called inappropriately.
1.3645 +** Perhaps it was called on a [prepared statement] that has
1.3646 +** already been [sqlite3_finalize | finalized] or on one that had
1.3647 +** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
1.3648 +** be the case that the same database connection is being used by two or
1.3649 +** more threads at the same moment in time.
1.3650 +**
1.3651 +** For all versions of SQLite up to and including 3.6.23.1, a call to
1.3652 +** [sqlite3_reset()] was required after sqlite3_step() returned anything
1.3653 +** other than [SQLITE_ROW] before any subsequent invocation of
1.3654 +** sqlite3_step(). Failure to reset the prepared statement using
1.3655 +** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
1.3656 +** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began
1.3657 +** calling [sqlite3_reset()] automatically in this circumstance rather
1.3658 +** than returning [SQLITE_MISUSE]. This is not considered a compatibility
1.3659 +** break because any application that ever receives an SQLITE_MISUSE error
1.3660 +** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
1.3661 +** can be used to restore the legacy behavior.
1.3662 +**
1.3663 +** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
1.3664 +** API always returns a generic error code, [SQLITE_ERROR], following any
1.3665 +** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
1.3666 +** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
1.3667 +** specific [error codes] that better describes the error.
1.3668 +** We admit that this is a goofy design. The problem has been fixed
1.3669 +** with the "v2" interface. If you prepare all of your SQL statements
1.3670 +** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
1.3671 +** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
1.3672 +** then the more specific [error codes] are returned directly
1.3673 +** by sqlite3_step(). The use of the "v2" interface is recommended.
1.3674 +*/
1.3675 +SQLITE_API int sqlite3_step(sqlite3_stmt*);
1.3676 +
1.3677 +/*
1.3678 +** CAPI3REF: Number of columns in a result set
1.3679 +**
1.3680 +** ^The sqlite3_data_count(P) interface returns the number of columns in the
1.3681 +** current row of the result set of [prepared statement] P.
1.3682 +** ^If prepared statement P does not have results ready to return
1.3683 +** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
1.3684 +** interfaces) then sqlite3_data_count(P) returns 0.
1.3685 +** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
1.3686 +** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
1.3687 +** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
1.3688 +** will return non-zero if previous call to [sqlite3_step](P) returned
1.3689 +** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
1.3690 +** where it always returns zero since each step of that multi-step
1.3691 +** pragma returns 0 columns of data.
1.3692 +**
1.3693 +** See also: [sqlite3_column_count()]
1.3694 +*/
1.3695 +SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
1.3696 +
1.3697 +/*
1.3698 +** CAPI3REF: Fundamental Datatypes
1.3699 +** KEYWORDS: SQLITE_TEXT
1.3700 +**
1.3701 +** ^(Every value in SQLite has one of five fundamental datatypes:
1.3702 +**
1.3703 +** <ul>
1.3704 +** <li> 64-bit signed integer
1.3705 +** <li> 64-bit IEEE floating point number
1.3706 +** <li> string
1.3707 +** <li> BLOB
1.3708 +** <li> NULL
1.3709 +** </ul>)^
1.3710 +**
1.3711 +** These constants are codes for each of those types.
1.3712 +**
1.3713 +** Note that the SQLITE_TEXT constant was also used in SQLite version 2
1.3714 +** for a completely different meaning. Software that links against both
1.3715 +** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
1.3716 +** SQLITE_TEXT.
1.3717 +*/
1.3718 +#define SQLITE_INTEGER 1
1.3719 +#define SQLITE_FLOAT 2
1.3720 +#define SQLITE_BLOB 4
1.3721 +#define SQLITE_NULL 5
1.3722 +#ifdef SQLITE_TEXT
1.3723 +# undef SQLITE_TEXT
1.3724 +#else
1.3725 +# define SQLITE_TEXT 3
1.3726 +#endif
1.3727 +#define SQLITE3_TEXT 3
1.3728 +
1.3729 +/*
1.3730 +** CAPI3REF: Result Values From A Query
1.3731 +** KEYWORDS: {column access functions}
1.3732 +**
1.3733 +** These routines form the "result set" interface.
1.3734 +**
1.3735 +** ^These routines return information about a single column of the current
1.3736 +** result row of a query. ^In every case the first argument is a pointer
1.3737 +** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
1.3738 +** that was returned from [sqlite3_prepare_v2()] or one of its variants)
1.3739 +** and the second argument is the index of the column for which information
1.3740 +** should be returned. ^The leftmost column of the result set has the index 0.
1.3741 +** ^The number of columns in the result can be determined using
1.3742 +** [sqlite3_column_count()].
1.3743 +**
1.3744 +** If the SQL statement does not currently point to a valid row, or if the
1.3745 +** column index is out of range, the result is undefined.
1.3746 +** These routines may only be called when the most recent call to
1.3747 +** [sqlite3_step()] has returned [SQLITE_ROW] and neither
1.3748 +** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
1.3749 +** If any of these routines are called after [sqlite3_reset()] or
1.3750 +** [sqlite3_finalize()] or after [sqlite3_step()] has returned
1.3751 +** something other than [SQLITE_ROW], the results are undefined.
1.3752 +** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
1.3753 +** are called from a different thread while any of these routines
1.3754 +** are pending, then the results are undefined.
1.3755 +**
1.3756 +** ^The sqlite3_column_type() routine returns the
1.3757 +** [SQLITE_INTEGER | datatype code] for the initial data type
1.3758 +** of the result column. ^The returned value is one of [SQLITE_INTEGER],
1.3759 +** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
1.3760 +** returned by sqlite3_column_type() is only meaningful if no type
1.3761 +** conversions have occurred as described below. After a type conversion,
1.3762 +** the value returned by sqlite3_column_type() is undefined. Future
1.3763 +** versions of SQLite may change the behavior of sqlite3_column_type()
1.3764 +** following a type conversion.
1.3765 +**
1.3766 +** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
1.3767 +** routine returns the number of bytes in that BLOB or string.
1.3768 +** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
1.3769 +** the string to UTF-8 and then returns the number of bytes.
1.3770 +** ^If the result is a numeric value then sqlite3_column_bytes() uses
1.3771 +** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
1.3772 +** the number of bytes in that string.
1.3773 +** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
1.3774 +**
1.3775 +** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
1.3776 +** routine returns the number of bytes in that BLOB or string.
1.3777 +** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
1.3778 +** the string to UTF-16 and then returns the number of bytes.
1.3779 +** ^If the result is a numeric value then sqlite3_column_bytes16() uses
1.3780 +** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
1.3781 +** the number of bytes in that string.
1.3782 +** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
1.3783 +**
1.3784 +** ^The values returned by [sqlite3_column_bytes()] and
1.3785 +** [sqlite3_column_bytes16()] do not include the zero terminators at the end
1.3786 +** of the string. ^For clarity: the values returned by
1.3787 +** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
1.3788 +** bytes in the string, not the number of characters.
1.3789 +**
1.3790 +** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
1.3791 +** even empty strings, are always zero-terminated. ^The return
1.3792 +** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
1.3793 +**
1.3794 +** ^The object returned by [sqlite3_column_value()] is an
1.3795 +** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
1.3796 +** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
1.3797 +** If the [unprotected sqlite3_value] object returned by
1.3798 +** [sqlite3_column_value()] is used in any other way, including calls
1.3799 +** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
1.3800 +** or [sqlite3_value_bytes()], then the behavior is undefined.
1.3801 +**
1.3802 +** These routines attempt to convert the value where appropriate. ^For
1.3803 +** example, if the internal representation is FLOAT and a text result
1.3804 +** is requested, [sqlite3_snprintf()] is used internally to perform the
1.3805 +** conversion automatically. ^(The following table details the conversions
1.3806 +** that are applied:
1.3807 +**
1.3808 +** <blockquote>
1.3809 +** <table border="1">
1.3810 +** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
1.3811 +**
1.3812 +** <tr><td> NULL <td> INTEGER <td> Result is 0
1.3813 +** <tr><td> NULL <td> FLOAT <td> Result is 0.0
1.3814 +** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer
1.3815 +** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer
1.3816 +** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
1.3817 +** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
1.3818 +** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
1.3819 +** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER
1.3820 +** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
1.3821 +** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB
1.3822 +** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER
1.3823 +** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL
1.3824 +** <tr><td> TEXT <td> BLOB <td> No change
1.3825 +** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER
1.3826 +** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL
1.3827 +** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
1.3828 +** </table>
1.3829 +** </blockquote>)^
1.3830 +**
1.3831 +** The table above makes reference to standard C library functions atoi()
1.3832 +** and atof(). SQLite does not really use these functions. It has its
1.3833 +** own equivalent internal routines. The atoi() and atof() names are
1.3834 +** used in the table for brevity and because they are familiar to most
1.3835 +** C programmers.
1.3836 +**
1.3837 +** Note that when type conversions occur, pointers returned by prior
1.3838 +** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
1.3839 +** sqlite3_column_text16() may be invalidated.
1.3840 +** Type conversions and pointer invalidations might occur
1.3841 +** in the following cases:
1.3842 +**
1.3843 +** <ul>
1.3844 +** <li> The initial content is a BLOB and sqlite3_column_text() or
1.3845 +** sqlite3_column_text16() is called. A zero-terminator might
1.3846 +** need to be added to the string.</li>
1.3847 +** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
1.3848 +** sqlite3_column_text16() is called. The content must be converted
1.3849 +** to UTF-16.</li>
1.3850 +** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
1.3851 +** sqlite3_column_text() is called. The content must be converted
1.3852 +** to UTF-8.</li>
1.3853 +** </ul>
1.3854 +**
1.3855 +** ^Conversions between UTF-16be and UTF-16le are always done in place and do
1.3856 +** not invalidate a prior pointer, though of course the content of the buffer
1.3857 +** that the prior pointer references will have been modified. Other kinds
1.3858 +** of conversion are done in place when it is possible, but sometimes they
1.3859 +** are not possible and in those cases prior pointers are invalidated.
1.3860 +**
1.3861 +** The safest and easiest to remember policy is to invoke these routines
1.3862 +** in one of the following ways:
1.3863 +**
1.3864 +** <ul>
1.3865 +** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
1.3866 +** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
1.3867 +** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
1.3868 +** </ul>
1.3869 +**
1.3870 +** In other words, you should call sqlite3_column_text(),
1.3871 +** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
1.3872 +** into the desired format, then invoke sqlite3_column_bytes() or
1.3873 +** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
1.3874 +** to sqlite3_column_text() or sqlite3_column_blob() with calls to
1.3875 +** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
1.3876 +** with calls to sqlite3_column_bytes().
1.3877 +**
1.3878 +** ^The pointers returned are valid until a type conversion occurs as
1.3879 +** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
1.3880 +** [sqlite3_finalize()] is called. ^The memory space used to hold strings
1.3881 +** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
1.3882 +** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
1.3883 +** [sqlite3_free()].
1.3884 +**
1.3885 +** ^(If a memory allocation error occurs during the evaluation of any
1.3886 +** of these routines, a default value is returned. The default value
1.3887 +** is either the integer 0, the floating point number 0.0, or a NULL
1.3888 +** pointer. Subsequent calls to [sqlite3_errcode()] will return
1.3889 +** [SQLITE_NOMEM].)^
1.3890 +*/
1.3891 +SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
1.3892 +SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
1.3893 +SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
1.3894 +SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
1.3895 +SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
1.3896 +SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
1.3897 +SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
1.3898 +SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
1.3899 +SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
1.3900 +SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
1.3901 +
1.3902 +/*
1.3903 +** CAPI3REF: Destroy A Prepared Statement Object
1.3904 +**
1.3905 +** ^The sqlite3_finalize() function is called to delete a [prepared statement].
1.3906 +** ^If the most recent evaluation of the statement encountered no errors
1.3907 +** or if the statement is never been evaluated, then sqlite3_finalize() returns
1.3908 +** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
1.3909 +** sqlite3_finalize(S) returns the appropriate [error code] or
1.3910 +** [extended error code].
1.3911 +**
1.3912 +** ^The sqlite3_finalize(S) routine can be called at any point during
1.3913 +** the life cycle of [prepared statement] S:
1.3914 +** before statement S is ever evaluated, after
1.3915 +** one or more calls to [sqlite3_reset()], or after any call
1.3916 +** to [sqlite3_step()] regardless of whether or not the statement has
1.3917 +** completed execution.
1.3918 +**
1.3919 +** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
1.3920 +**
1.3921 +** The application must finalize every [prepared statement] in order to avoid
1.3922 +** resource leaks. It is a grievous error for the application to try to use
1.3923 +** a prepared statement after it has been finalized. Any use of a prepared
1.3924 +** statement after it has been finalized can result in undefined and
1.3925 +** undesirable behavior such as segfaults and heap corruption.
1.3926 +*/
1.3927 +SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
1.3928 +
1.3929 +/*
1.3930 +** CAPI3REF: Reset A Prepared Statement Object
1.3931 +**
1.3932 +** The sqlite3_reset() function is called to reset a [prepared statement]
1.3933 +** object back to its initial state, ready to be re-executed.
1.3934 +** ^Any SQL statement variables that had values bound to them using
1.3935 +** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
1.3936 +** Use [sqlite3_clear_bindings()] to reset the bindings.
1.3937 +**
1.3938 +** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
1.3939 +** back to the beginning of its program.
1.3940 +**
1.3941 +** ^If the most recent call to [sqlite3_step(S)] for the
1.3942 +** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
1.3943 +** or if [sqlite3_step(S)] has never before been called on S,
1.3944 +** then [sqlite3_reset(S)] returns [SQLITE_OK].
1.3945 +**
1.3946 +** ^If the most recent call to [sqlite3_step(S)] for the
1.3947 +** [prepared statement] S indicated an error, then
1.3948 +** [sqlite3_reset(S)] returns an appropriate [error code].
1.3949 +**
1.3950 +** ^The [sqlite3_reset(S)] interface does not change the values
1.3951 +** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
1.3952 +*/
1.3953 +SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
1.3954 +
1.3955 +/*
1.3956 +** CAPI3REF: Create Or Redefine SQL Functions
1.3957 +** KEYWORDS: {function creation routines}
1.3958 +** KEYWORDS: {application-defined SQL function}
1.3959 +** KEYWORDS: {application-defined SQL functions}
1.3960 +**
1.3961 +** ^These functions (collectively known as "function creation routines")
1.3962 +** are used to add SQL functions or aggregates or to redefine the behavior
1.3963 +** of existing SQL functions or aggregates. The only differences between
1.3964 +** these routines are the text encoding expected for
1.3965 +** the second parameter (the name of the function being created)
1.3966 +** and the presence or absence of a destructor callback for
1.3967 +** the application data pointer.
1.3968 +**
1.3969 +** ^The first parameter is the [database connection] to which the SQL
1.3970 +** function is to be added. ^If an application uses more than one database
1.3971 +** connection then application-defined SQL functions must be added
1.3972 +** to each database connection separately.
1.3973 +**
1.3974 +** ^The second parameter is the name of the SQL function to be created or
1.3975 +** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
1.3976 +** representation, exclusive of the zero-terminator. ^Note that the name
1.3977 +** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
1.3978 +** ^Any attempt to create a function with a longer name
1.3979 +** will result in [SQLITE_MISUSE] being returned.
1.3980 +**
1.3981 +** ^The third parameter (nArg)
1.3982 +** is the number of arguments that the SQL function or
1.3983 +** aggregate takes. ^If this parameter is -1, then the SQL function or
1.3984 +** aggregate may take any number of arguments between 0 and the limit
1.3985 +** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
1.3986 +** parameter is less than -1 or greater than 127 then the behavior is
1.3987 +** undefined.
1.3988 +**
1.3989 +** ^The fourth parameter, eTextRep, specifies what
1.3990 +** [SQLITE_UTF8 | text encoding] this SQL function prefers for
1.3991 +** its parameters. The application should set this parameter to
1.3992 +** [SQLITE_UTF16LE] if the function implementation invokes
1.3993 +** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
1.3994 +** implementation invokes [sqlite3_value_text16be()] on an input, or
1.3995 +** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
1.3996 +** otherwise. ^The same SQL function may be registered multiple times using
1.3997 +** different preferred text encodings, with different implementations for
1.3998 +** each encoding.
1.3999 +** ^When multiple implementations of the same function are available, SQLite
1.4000 +** will pick the one that involves the least amount of data conversion.
1.4001 +**
1.4002 +** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
1.4003 +** to signal that the function will always return the same result given
1.4004 +** the same inputs within a single SQL statement. Most SQL functions are
1.4005 +** deterministic. The built-in [random()] SQL function is an example of a
1.4006 +** function that is not deterministic. The SQLite query planner is able to
1.4007 +** perform additional optimizations on deterministic functions, so use
1.4008 +** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
1.4009 +**
1.4010 +** ^(The fifth parameter is an arbitrary pointer. The implementation of the
1.4011 +** function can gain access to this pointer using [sqlite3_user_data()].)^
1.4012 +**
1.4013 +** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
1.4014 +** pointers to C-language functions that implement the SQL function or
1.4015 +** aggregate. ^A scalar SQL function requires an implementation of the xFunc
1.4016 +** callback only; NULL pointers must be passed as the xStep and xFinal
1.4017 +** parameters. ^An aggregate SQL function requires an implementation of xStep
1.4018 +** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
1.4019 +** SQL function or aggregate, pass NULL pointers for all three function
1.4020 +** callbacks.
1.4021 +**
1.4022 +** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
1.4023 +** then it is destructor for the application data pointer.
1.4024 +** The destructor is invoked when the function is deleted, either by being
1.4025 +** overloaded or when the database connection closes.)^
1.4026 +** ^The destructor is also invoked if the call to
1.4027 +** sqlite3_create_function_v2() fails.
1.4028 +** ^When the destructor callback of the tenth parameter is invoked, it
1.4029 +** is passed a single argument which is a copy of the application data
1.4030 +** pointer which was the fifth parameter to sqlite3_create_function_v2().
1.4031 +**
1.4032 +** ^It is permitted to register multiple implementations of the same
1.4033 +** functions with the same name but with either differing numbers of
1.4034 +** arguments or differing preferred text encodings. ^SQLite will use
1.4035 +** the implementation that most closely matches the way in which the
1.4036 +** SQL function is used. ^A function implementation with a non-negative
1.4037 +** nArg parameter is a better match than a function implementation with
1.4038 +** a negative nArg. ^A function where the preferred text encoding
1.4039 +** matches the database encoding is a better
1.4040 +** match than a function where the encoding is different.
1.4041 +** ^A function where the encoding difference is between UTF16le and UTF16be
1.4042 +** is a closer match than a function where the encoding difference is
1.4043 +** between UTF8 and UTF16.
1.4044 +**
1.4045 +** ^Built-in functions may be overloaded by new application-defined functions.
1.4046 +**
1.4047 +** ^An application-defined function is permitted to call other
1.4048 +** SQLite interfaces. However, such calls must not
1.4049 +** close the database connection nor finalize or reset the prepared
1.4050 +** statement in which the function is running.
1.4051 +*/
1.4052 +SQLITE_API int sqlite3_create_function(
1.4053 + sqlite3 *db,
1.4054 + const char *zFunctionName,
1.4055 + int nArg,
1.4056 + int eTextRep,
1.4057 + void *pApp,
1.4058 + void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
1.4059 + void (*xStep)(sqlite3_context*,int,sqlite3_value**),
1.4060 + void (*xFinal)(sqlite3_context*)
1.4061 +);
1.4062 +SQLITE_API int sqlite3_create_function16(
1.4063 + sqlite3 *db,
1.4064 + const void *zFunctionName,
1.4065 + int nArg,
1.4066 + int eTextRep,
1.4067 + void *pApp,
1.4068 + void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
1.4069 + void (*xStep)(sqlite3_context*,int,sqlite3_value**),
1.4070 + void (*xFinal)(sqlite3_context*)
1.4071 +);
1.4072 +SQLITE_API int sqlite3_create_function_v2(
1.4073 + sqlite3 *db,
1.4074 + const char *zFunctionName,
1.4075 + int nArg,
1.4076 + int eTextRep,
1.4077 + void *pApp,
1.4078 + void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
1.4079 + void (*xStep)(sqlite3_context*,int,sqlite3_value**),
1.4080 + void (*xFinal)(sqlite3_context*),
1.4081 + void(*xDestroy)(void*)
1.4082 +);
1.4083 +
1.4084 +/*
1.4085 +** CAPI3REF: Text Encodings
1.4086 +**
1.4087 +** These constant define integer codes that represent the various
1.4088 +** text encodings supported by SQLite.
1.4089 +*/
1.4090 +#define SQLITE_UTF8 1
1.4091 +#define SQLITE_UTF16LE 2
1.4092 +#define SQLITE_UTF16BE 3
1.4093 +#define SQLITE_UTF16 4 /* Use native byte order */
1.4094 +#define SQLITE_ANY 5 /* Deprecated */
1.4095 +#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
1.4096 +
1.4097 +/*
1.4098 +** CAPI3REF: Function Flags
1.4099 +**
1.4100 +** These constants may be ORed together with the
1.4101 +** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
1.4102 +** to [sqlite3_create_function()], [sqlite3_create_function16()], or
1.4103 +** [sqlite3_create_function_v2()].
1.4104 +*/
1.4105 +#define SQLITE_DETERMINISTIC 0x800
1.4106 +
1.4107 +/*
1.4108 +** CAPI3REF: Deprecated Functions
1.4109 +** DEPRECATED
1.4110 +**
1.4111 +** These functions are [deprecated]. In order to maintain
1.4112 +** backwards compatibility with older code, these functions continue
1.4113 +** to be supported. However, new applications should avoid
1.4114 +** the use of these functions. To help encourage people to avoid
1.4115 +** using these functions, we are not going to tell you what they do.
1.4116 +*/
1.4117 +#ifndef SQLITE_OMIT_DEPRECATED
1.4118 +SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
1.4119 +SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
1.4120 +SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
1.4121 +SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
1.4122 +SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
1.4123 +SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
1.4124 + void*,sqlite3_int64);
1.4125 +#endif
1.4126 +
1.4127 +/*
1.4128 +** CAPI3REF: Obtaining SQL Function Parameter Values
1.4129 +**
1.4130 +** The C-language implementation of SQL functions and aggregates uses
1.4131 +** this set of interface routines to access the parameter values on
1.4132 +** the function or aggregate.
1.4133 +**
1.4134 +** The xFunc (for scalar functions) or xStep (for aggregates) parameters
1.4135 +** to [sqlite3_create_function()] and [sqlite3_create_function16()]
1.4136 +** define callbacks that implement the SQL functions and aggregates.
1.4137 +** The 3rd parameter to these callbacks is an array of pointers to
1.4138 +** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
1.4139 +** each parameter to the SQL function. These routines are used to
1.4140 +** extract values from the [sqlite3_value] objects.
1.4141 +**
1.4142 +** These routines work only with [protected sqlite3_value] objects.
1.4143 +** Any attempt to use these routines on an [unprotected sqlite3_value]
1.4144 +** object results in undefined behavior.
1.4145 +**
1.4146 +** ^These routines work just like the corresponding [column access functions]
1.4147 +** except that these routines take a single [protected sqlite3_value] object
1.4148 +** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
1.4149 +**
1.4150 +** ^The sqlite3_value_text16() interface extracts a UTF-16 string
1.4151 +** in the native byte-order of the host machine. ^The
1.4152 +** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
1.4153 +** extract UTF-16 strings as big-endian and little-endian respectively.
1.4154 +**
1.4155 +** ^(The sqlite3_value_numeric_type() interface attempts to apply
1.4156 +** numeric affinity to the value. This means that an attempt is
1.4157 +** made to convert the value to an integer or floating point. If
1.4158 +** such a conversion is possible without loss of information (in other
1.4159 +** words, if the value is a string that looks like a number)
1.4160 +** then the conversion is performed. Otherwise no conversion occurs.
1.4161 +** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
1.4162 +**
1.4163 +** Please pay particular attention to the fact that the pointer returned
1.4164 +** from [sqlite3_value_blob()], [sqlite3_value_text()], or
1.4165 +** [sqlite3_value_text16()] can be invalidated by a subsequent call to
1.4166 +** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
1.4167 +** or [sqlite3_value_text16()].
1.4168 +**
1.4169 +** These routines must be called from the same thread as
1.4170 +** the SQL function that supplied the [sqlite3_value*] parameters.
1.4171 +*/
1.4172 +SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
1.4173 +SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
1.4174 +SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
1.4175 +SQLITE_API double sqlite3_value_double(sqlite3_value*);
1.4176 +SQLITE_API int sqlite3_value_int(sqlite3_value*);
1.4177 +SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
1.4178 +SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
1.4179 +SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
1.4180 +SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
1.4181 +SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
1.4182 +SQLITE_API int sqlite3_value_type(sqlite3_value*);
1.4183 +SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
1.4184 +
1.4185 +/*
1.4186 +** CAPI3REF: Obtain Aggregate Function Context
1.4187 +**
1.4188 +** Implementations of aggregate SQL functions use this
1.4189 +** routine to allocate memory for storing their state.
1.4190 +**
1.4191 +** ^The first time the sqlite3_aggregate_context(C,N) routine is called
1.4192 +** for a particular aggregate function, SQLite
1.4193 +** allocates N of memory, zeroes out that memory, and returns a pointer
1.4194 +** to the new memory. ^On second and subsequent calls to
1.4195 +** sqlite3_aggregate_context() for the same aggregate function instance,
1.4196 +** the same buffer is returned. Sqlite3_aggregate_context() is normally
1.4197 +** called once for each invocation of the xStep callback and then one
1.4198 +** last time when the xFinal callback is invoked. ^(When no rows match
1.4199 +** an aggregate query, the xStep() callback of the aggregate function
1.4200 +** implementation is never called and xFinal() is called exactly once.
1.4201 +** In those cases, sqlite3_aggregate_context() might be called for the
1.4202 +** first time from within xFinal().)^
1.4203 +**
1.4204 +** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
1.4205 +** when first called if N is less than or equal to zero or if a memory
1.4206 +** allocate error occurs.
1.4207 +**
1.4208 +** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
1.4209 +** determined by the N parameter on first successful call. Changing the
1.4210 +** value of N in subsequent call to sqlite3_aggregate_context() within
1.4211 +** the same aggregate function instance will not resize the memory
1.4212 +** allocation.)^ Within the xFinal callback, it is customary to set
1.4213 +** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
1.4214 +** pointless memory allocations occur.
1.4215 +**
1.4216 +** ^SQLite automatically frees the memory allocated by
1.4217 +** sqlite3_aggregate_context() when the aggregate query concludes.
1.4218 +**
1.4219 +** The first parameter must be a copy of the
1.4220 +** [sqlite3_context | SQL function context] that is the first parameter
1.4221 +** to the xStep or xFinal callback routine that implements the aggregate
1.4222 +** function.
1.4223 +**
1.4224 +** This routine must be called from the same thread in which
1.4225 +** the aggregate SQL function is running.
1.4226 +*/
1.4227 +SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
1.4228 +
1.4229 +/*
1.4230 +** CAPI3REF: User Data For Functions
1.4231 +**
1.4232 +** ^The sqlite3_user_data() interface returns a copy of
1.4233 +** the pointer that was the pUserData parameter (the 5th parameter)
1.4234 +** of the [sqlite3_create_function()]
1.4235 +** and [sqlite3_create_function16()] routines that originally
1.4236 +** registered the application defined function.
1.4237 +**
1.4238 +** This routine must be called from the same thread in which
1.4239 +** the application-defined function is running.
1.4240 +*/
1.4241 +SQLITE_API void *sqlite3_user_data(sqlite3_context*);
1.4242 +
1.4243 +/*
1.4244 +** CAPI3REF: Database Connection For Functions
1.4245 +**
1.4246 +** ^The sqlite3_context_db_handle() interface returns a copy of
1.4247 +** the pointer to the [database connection] (the 1st parameter)
1.4248 +** of the [sqlite3_create_function()]
1.4249 +** and [sqlite3_create_function16()] routines that originally
1.4250 +** registered the application defined function.
1.4251 +*/
1.4252 +SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
1.4253 +
1.4254 +/*
1.4255 +** CAPI3REF: Function Auxiliary Data
1.4256 +**
1.4257 +** These functions may be used by (non-aggregate) SQL functions to
1.4258 +** associate metadata with argument values. If the same value is passed to
1.4259 +** multiple invocations of the same SQL function during query execution, under
1.4260 +** some circumstances the associated metadata may be preserved. An example
1.4261 +** of where this might be useful is in a regular-expression matching
1.4262 +** function. The compiled version of the regular expression can be stored as
1.4263 +** metadata associated with the pattern string.
1.4264 +** Then as long as the pattern string remains the same,
1.4265 +** the compiled regular expression can be reused on multiple
1.4266 +** invocations of the same function.
1.4267 +**
1.4268 +** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
1.4269 +** associated by the sqlite3_set_auxdata() function with the Nth argument
1.4270 +** value to the application-defined function. ^If there is no metadata
1.4271 +** associated with the function argument, this sqlite3_get_auxdata() interface
1.4272 +** returns a NULL pointer.
1.4273 +**
1.4274 +** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
1.4275 +** argument of the application-defined function. ^Subsequent
1.4276 +** calls to sqlite3_get_auxdata(C,N) return P from the most recent
1.4277 +** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
1.4278 +** NULL if the metadata has been discarded.
1.4279 +** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
1.4280 +** SQLite will invoke the destructor function X with parameter P exactly
1.4281 +** once, when the metadata is discarded.
1.4282 +** SQLite is free to discard the metadata at any time, including: <ul>
1.4283 +** <li> when the corresponding function parameter changes, or
1.4284 +** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
1.4285 +** SQL statement, or
1.4286 +** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
1.4287 +** <li> during the original sqlite3_set_auxdata() call when a memory
1.4288 +** allocation error occurs. </ul>)^
1.4289 +**
1.4290 +** Note the last bullet in particular. The destructor X in
1.4291 +** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
1.4292 +** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
1.4293 +** should be called near the end of the function implementation and the
1.4294 +** function implementation should not make any use of P after
1.4295 +** sqlite3_set_auxdata() has been called.
1.4296 +**
1.4297 +** ^(In practice, metadata is preserved between function calls for
1.4298 +** function parameters that are compile-time constants, including literal
1.4299 +** values and [parameters] and expressions composed from the same.)^
1.4300 +**
1.4301 +** These routines must be called from the same thread in which
1.4302 +** the SQL function is running.
1.4303 +*/
1.4304 +SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
1.4305 +SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
1.4306 +
1.4307 +
1.4308 +/*
1.4309 +** CAPI3REF: Constants Defining Special Destructor Behavior
1.4310 +**
1.4311 +** These are special values for the destructor that is passed in as the
1.4312 +** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
1.4313 +** argument is SQLITE_STATIC, it means that the content pointer is constant
1.4314 +** and will never change. It does not need to be destroyed. ^The
1.4315 +** SQLITE_TRANSIENT value means that the content will likely change in
1.4316 +** the near future and that SQLite should make its own private copy of
1.4317 +** the content before returning.
1.4318 +**
1.4319 +** The typedef is necessary to work around problems in certain
1.4320 +** C++ compilers.
1.4321 +*/
1.4322 +typedef void (*sqlite3_destructor_type)(void*);
1.4323 +#define SQLITE_STATIC ((sqlite3_destructor_type)0)
1.4324 +#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
1.4325 +
1.4326 +/*
1.4327 +** CAPI3REF: Setting The Result Of An SQL Function
1.4328 +**
1.4329 +** These routines are used by the xFunc or xFinal callbacks that
1.4330 +** implement SQL functions and aggregates. See
1.4331 +** [sqlite3_create_function()] and [sqlite3_create_function16()]
1.4332 +** for additional information.
1.4333 +**
1.4334 +** These functions work very much like the [parameter binding] family of
1.4335 +** functions used to bind values to host parameters in prepared statements.
1.4336 +** Refer to the [SQL parameter] documentation for additional information.
1.4337 +**
1.4338 +** ^The sqlite3_result_blob() interface sets the result from
1.4339 +** an application-defined function to be the BLOB whose content is pointed
1.4340 +** to by the second parameter and which is N bytes long where N is the
1.4341 +** third parameter.
1.4342 +**
1.4343 +** ^The sqlite3_result_zeroblob() interfaces set the result of
1.4344 +** the application-defined function to be a BLOB containing all zero
1.4345 +** bytes and N bytes in size, where N is the value of the 2nd parameter.
1.4346 +**
1.4347 +** ^The sqlite3_result_double() interface sets the result from
1.4348 +** an application-defined function to be a floating point value specified
1.4349 +** by its 2nd argument.
1.4350 +**
1.4351 +** ^The sqlite3_result_error() and sqlite3_result_error16() functions
1.4352 +** cause the implemented SQL function to throw an exception.
1.4353 +** ^SQLite uses the string pointed to by the
1.4354 +** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
1.4355 +** as the text of an error message. ^SQLite interprets the error
1.4356 +** message string from sqlite3_result_error() as UTF-8. ^SQLite
1.4357 +** interprets the string from sqlite3_result_error16() as UTF-16 in native
1.4358 +** byte order. ^If the third parameter to sqlite3_result_error()
1.4359 +** or sqlite3_result_error16() is negative then SQLite takes as the error
1.4360 +** message all text up through the first zero character.
1.4361 +** ^If the third parameter to sqlite3_result_error() or
1.4362 +** sqlite3_result_error16() is non-negative then SQLite takes that many
1.4363 +** bytes (not characters) from the 2nd parameter as the error message.
1.4364 +** ^The sqlite3_result_error() and sqlite3_result_error16()
1.4365 +** routines make a private copy of the error message text before
1.4366 +** they return. Hence, the calling function can deallocate or
1.4367 +** modify the text after they return without harm.
1.4368 +** ^The sqlite3_result_error_code() function changes the error code
1.4369 +** returned by SQLite as a result of an error in a function. ^By default,
1.4370 +** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
1.4371 +** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
1.4372 +**
1.4373 +** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
1.4374 +** error indicating that a string or BLOB is too long to represent.
1.4375 +**
1.4376 +** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
1.4377 +** error indicating that a memory allocation failed.
1.4378 +**
1.4379 +** ^The sqlite3_result_int() interface sets the return value
1.4380 +** of the application-defined function to be the 32-bit signed integer
1.4381 +** value given in the 2nd argument.
1.4382 +** ^The sqlite3_result_int64() interface sets the return value
1.4383 +** of the application-defined function to be the 64-bit signed integer
1.4384 +** value given in the 2nd argument.
1.4385 +**
1.4386 +** ^The sqlite3_result_null() interface sets the return value
1.4387 +** of the application-defined function to be NULL.
1.4388 +**
1.4389 +** ^The sqlite3_result_text(), sqlite3_result_text16(),
1.4390 +** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
1.4391 +** set the return value of the application-defined function to be
1.4392 +** a text string which is represented as UTF-8, UTF-16 native byte order,
1.4393 +** UTF-16 little endian, or UTF-16 big endian, respectively.
1.4394 +** ^SQLite takes the text result from the application from
1.4395 +** the 2nd parameter of the sqlite3_result_text* interfaces.
1.4396 +** ^If the 3rd parameter to the sqlite3_result_text* interfaces
1.4397 +** is negative, then SQLite takes result text from the 2nd parameter
1.4398 +** through the first zero character.
1.4399 +** ^If the 3rd parameter to the sqlite3_result_text* interfaces
1.4400 +** is non-negative, then as many bytes (not characters) of the text
1.4401 +** pointed to by the 2nd parameter are taken as the application-defined
1.4402 +** function result. If the 3rd parameter is non-negative, then it
1.4403 +** must be the byte offset into the string where the NUL terminator would
1.4404 +** appear if the string where NUL terminated. If any NUL characters occur
1.4405 +** in the string at a byte offset that is less than the value of the 3rd
1.4406 +** parameter, then the resulting string will contain embedded NULs and the
1.4407 +** result of expressions operating on strings with embedded NULs is undefined.
1.4408 +** ^If the 4th parameter to the sqlite3_result_text* interfaces
1.4409 +** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
1.4410 +** function as the destructor on the text or BLOB result when it has
1.4411 +** finished using that result.
1.4412 +** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
1.4413 +** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
1.4414 +** assumes that the text or BLOB result is in constant space and does not
1.4415 +** copy the content of the parameter nor call a destructor on the content
1.4416 +** when it has finished using that result.
1.4417 +** ^If the 4th parameter to the sqlite3_result_text* interfaces
1.4418 +** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
1.4419 +** then SQLite makes a copy of the result into space obtained from
1.4420 +** from [sqlite3_malloc()] before it returns.
1.4421 +**
1.4422 +** ^The sqlite3_result_value() interface sets the result of
1.4423 +** the application-defined function to be a copy the
1.4424 +** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
1.4425 +** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
1.4426 +** so that the [sqlite3_value] specified in the parameter may change or
1.4427 +** be deallocated after sqlite3_result_value() returns without harm.
1.4428 +** ^A [protected sqlite3_value] object may always be used where an
1.4429 +** [unprotected sqlite3_value] object is required, so either
1.4430 +** kind of [sqlite3_value] object can be used with this interface.
1.4431 +**
1.4432 +** If these routines are called from within the different thread
1.4433 +** than the one containing the application-defined function that received
1.4434 +** the [sqlite3_context] pointer, the results are undefined.
1.4435 +*/
1.4436 +SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
1.4437 +SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
1.4438 +SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
1.4439 +SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
1.4440 +SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
1.4441 +SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
1.4442 +SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
1.4443 +SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
1.4444 +SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
1.4445 +SQLITE_API void sqlite3_result_null(sqlite3_context*);
1.4446 +SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
1.4447 +SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
1.4448 +SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
1.4449 +SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
1.4450 +SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
1.4451 +SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
1.4452 +
1.4453 +/*
1.4454 +** CAPI3REF: Define New Collating Sequences
1.4455 +**
1.4456 +** ^These functions add, remove, or modify a [collation] associated
1.4457 +** with the [database connection] specified as the first argument.
1.4458 +**
1.4459 +** ^The name of the collation is a UTF-8 string
1.4460 +** for sqlite3_create_collation() and sqlite3_create_collation_v2()
1.4461 +** and a UTF-16 string in native byte order for sqlite3_create_collation16().
1.4462 +** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
1.4463 +** considered to be the same name.
1.4464 +**
1.4465 +** ^(The third argument (eTextRep) must be one of the constants:
1.4466 +** <ul>
1.4467 +** <li> [SQLITE_UTF8],
1.4468 +** <li> [SQLITE_UTF16LE],
1.4469 +** <li> [SQLITE_UTF16BE],
1.4470 +** <li> [SQLITE_UTF16], or
1.4471 +** <li> [SQLITE_UTF16_ALIGNED].
1.4472 +** </ul>)^
1.4473 +** ^The eTextRep argument determines the encoding of strings passed
1.4474 +** to the collating function callback, xCallback.
1.4475 +** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
1.4476 +** force strings to be UTF16 with native byte order.
1.4477 +** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
1.4478 +** on an even byte address.
1.4479 +**
1.4480 +** ^The fourth argument, pArg, is an application data pointer that is passed
1.4481 +** through as the first argument to the collating function callback.
1.4482 +**
1.4483 +** ^The fifth argument, xCallback, is a pointer to the collating function.
1.4484 +** ^Multiple collating functions can be registered using the same name but
1.4485 +** with different eTextRep parameters and SQLite will use whichever
1.4486 +** function requires the least amount of data transformation.
1.4487 +** ^If the xCallback argument is NULL then the collating function is
1.4488 +** deleted. ^When all collating functions having the same name are deleted,
1.4489 +** that collation is no longer usable.
1.4490 +**
1.4491 +** ^The collating function callback is invoked with a copy of the pArg
1.4492 +** application data pointer and with two strings in the encoding specified
1.4493 +** by the eTextRep argument. The collating function must return an
1.4494 +** integer that is negative, zero, or positive
1.4495 +** if the first string is less than, equal to, or greater than the second,
1.4496 +** respectively. A collating function must always return the same answer
1.4497 +** given the same inputs. If two or more collating functions are registered
1.4498 +** to the same collation name (using different eTextRep values) then all
1.4499 +** must give an equivalent answer when invoked with equivalent strings.
1.4500 +** The collating function must obey the following properties for all
1.4501 +** strings A, B, and C:
1.4502 +**
1.4503 +** <ol>
1.4504 +** <li> If A==B then B==A.
1.4505 +** <li> If A==B and B==C then A==C.
1.4506 +** <li> If A<B THEN B>A.
1.4507 +** <li> If A<B and B<C then A<C.
1.4508 +** </ol>
1.4509 +**
1.4510 +** If a collating function fails any of the above constraints and that
1.4511 +** collating function is registered and used, then the behavior of SQLite
1.4512 +** is undefined.
1.4513 +**
1.4514 +** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
1.4515 +** with the addition that the xDestroy callback is invoked on pArg when
1.4516 +** the collating function is deleted.
1.4517 +** ^Collating functions are deleted when they are overridden by later
1.4518 +** calls to the collation creation functions or when the
1.4519 +** [database connection] is closed using [sqlite3_close()].
1.4520 +**
1.4521 +** ^The xDestroy callback is <u>not</u> called if the
1.4522 +** sqlite3_create_collation_v2() function fails. Applications that invoke
1.4523 +** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
1.4524 +** check the return code and dispose of the application data pointer
1.4525 +** themselves rather than expecting SQLite to deal with it for them.
1.4526 +** This is different from every other SQLite interface. The inconsistency
1.4527 +** is unfortunate but cannot be changed without breaking backwards
1.4528 +** compatibility.
1.4529 +**
1.4530 +** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
1.4531 +*/
1.4532 +SQLITE_API int sqlite3_create_collation(
1.4533 + sqlite3*,
1.4534 + const char *zName,
1.4535 + int eTextRep,
1.4536 + void *pArg,
1.4537 + int(*xCompare)(void*,int,const void*,int,const void*)
1.4538 +);
1.4539 +SQLITE_API int sqlite3_create_collation_v2(
1.4540 + sqlite3*,
1.4541 + const char *zName,
1.4542 + int eTextRep,
1.4543 + void *pArg,
1.4544 + int(*xCompare)(void*,int,const void*,int,const void*),
1.4545 + void(*xDestroy)(void*)
1.4546 +);
1.4547 +SQLITE_API int sqlite3_create_collation16(
1.4548 + sqlite3*,
1.4549 + const void *zName,
1.4550 + int eTextRep,
1.4551 + void *pArg,
1.4552 + int(*xCompare)(void*,int,const void*,int,const void*)
1.4553 +);
1.4554 +
1.4555 +/*
1.4556 +** CAPI3REF: Collation Needed Callbacks
1.4557 +**
1.4558 +** ^To avoid having to register all collation sequences before a database
1.4559 +** can be used, a single callback function may be registered with the
1.4560 +** [database connection] to be invoked whenever an undefined collation
1.4561 +** sequence is required.
1.4562 +**
1.4563 +** ^If the function is registered using the sqlite3_collation_needed() API,
1.4564 +** then it is passed the names of undefined collation sequences as strings
1.4565 +** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
1.4566 +** the names are passed as UTF-16 in machine native byte order.
1.4567 +** ^A call to either function replaces the existing collation-needed callback.
1.4568 +**
1.4569 +** ^(When the callback is invoked, the first argument passed is a copy
1.4570 +** of the second argument to sqlite3_collation_needed() or
1.4571 +** sqlite3_collation_needed16(). The second argument is the database
1.4572 +** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
1.4573 +** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
1.4574 +** sequence function required. The fourth parameter is the name of the
1.4575 +** required collation sequence.)^
1.4576 +**
1.4577 +** The callback function should register the desired collation using
1.4578 +** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
1.4579 +** [sqlite3_create_collation_v2()].
1.4580 +*/
1.4581 +SQLITE_API int sqlite3_collation_needed(
1.4582 + sqlite3*,
1.4583 + void*,
1.4584 + void(*)(void*,sqlite3*,int eTextRep,const char*)
1.4585 +);
1.4586 +SQLITE_API int sqlite3_collation_needed16(
1.4587 + sqlite3*,
1.4588 + void*,
1.4589 + void(*)(void*,sqlite3*,int eTextRep,const void*)
1.4590 +);
1.4591 +
1.4592 +#ifdef SQLITE_HAS_CODEC
1.4593 +/*
1.4594 +** Specify the key for an encrypted database. This routine should be
1.4595 +** called right after sqlite3_open().
1.4596 +**
1.4597 +** The code to implement this API is not available in the public release
1.4598 +** of SQLite.
1.4599 +*/
1.4600 +SQLITE_API int sqlite3_key(
1.4601 + sqlite3 *db, /* Database to be rekeyed */
1.4602 + const void *pKey, int nKey /* The key */
1.4603 +);
1.4604 +SQLITE_API int sqlite3_key_v2(
1.4605 + sqlite3 *db, /* Database to be rekeyed */
1.4606 + const char *zDbName, /* Name of the database */
1.4607 + const void *pKey, int nKey /* The key */
1.4608 +);
1.4609 +
1.4610 +/*
1.4611 +** Change the key on an open database. If the current database is not
1.4612 +** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
1.4613 +** database is decrypted.
1.4614 +**
1.4615 +** The code to implement this API is not available in the public release
1.4616 +** of SQLite.
1.4617 +*/
1.4618 +SQLITE_API int sqlite3_rekey(
1.4619 + sqlite3 *db, /* Database to be rekeyed */
1.4620 + const void *pKey, int nKey /* The new key */
1.4621 +);
1.4622 +SQLITE_API int sqlite3_rekey_v2(
1.4623 + sqlite3 *db, /* Database to be rekeyed */
1.4624 + const char *zDbName, /* Name of the database */
1.4625 + const void *pKey, int nKey /* The new key */
1.4626 +);
1.4627 +
1.4628 +/*
1.4629 +** Specify the activation key for a SEE database. Unless
1.4630 +** activated, none of the SEE routines will work.
1.4631 +*/
1.4632 +SQLITE_API void sqlite3_activate_see(
1.4633 + const char *zPassPhrase /* Activation phrase */
1.4634 +);
1.4635 +#endif
1.4636 +
1.4637 +#ifdef SQLITE_ENABLE_CEROD
1.4638 +/*
1.4639 +** Specify the activation key for a CEROD database. Unless
1.4640 +** activated, none of the CEROD routines will work.
1.4641 +*/
1.4642 +SQLITE_API void sqlite3_activate_cerod(
1.4643 + const char *zPassPhrase /* Activation phrase */
1.4644 +);
1.4645 +#endif
1.4646 +
1.4647 +/*
1.4648 +** CAPI3REF: Suspend Execution For A Short Time
1.4649 +**
1.4650 +** The sqlite3_sleep() function causes the current thread to suspend execution
1.4651 +** for at least a number of milliseconds specified in its parameter.
1.4652 +**
1.4653 +** If the operating system does not support sleep requests with
1.4654 +** millisecond time resolution, then the time will be rounded up to
1.4655 +** the nearest second. The number of milliseconds of sleep actually
1.4656 +** requested from the operating system is returned.
1.4657 +**
1.4658 +** ^SQLite implements this interface by calling the xSleep()
1.4659 +** method of the default [sqlite3_vfs] object. If the xSleep() method
1.4660 +** of the default VFS is not implemented correctly, or not implemented at
1.4661 +** all, then the behavior of sqlite3_sleep() may deviate from the description
1.4662 +** in the previous paragraphs.
1.4663 +*/
1.4664 +SQLITE_API int sqlite3_sleep(int);
1.4665 +
1.4666 +/*
1.4667 +** CAPI3REF: Name Of The Folder Holding Temporary Files
1.4668 +**
1.4669 +** ^(If this global variable is made to point to a string which is
1.4670 +** the name of a folder (a.k.a. directory), then all temporary files
1.4671 +** created by SQLite when using a built-in [sqlite3_vfs | VFS]
1.4672 +** will be placed in that directory.)^ ^If this variable
1.4673 +** is a NULL pointer, then SQLite performs a search for an appropriate
1.4674 +** temporary file directory.
1.4675 +**
1.4676 +** It is not safe to read or modify this variable in more than one
1.4677 +** thread at a time. It is not safe to read or modify this variable
1.4678 +** if a [database connection] is being used at the same time in a separate
1.4679 +** thread.
1.4680 +** It is intended that this variable be set once
1.4681 +** as part of process initialization and before any SQLite interface
1.4682 +** routines have been called and that this variable remain unchanged
1.4683 +** thereafter.
1.4684 +**
1.4685 +** ^The [temp_store_directory pragma] may modify this variable and cause
1.4686 +** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
1.4687 +** the [temp_store_directory pragma] always assumes that any string
1.4688 +** that this variable points to is held in memory obtained from
1.4689 +** [sqlite3_malloc] and the pragma may attempt to free that memory
1.4690 +** using [sqlite3_free].
1.4691 +** Hence, if this variable is modified directly, either it should be
1.4692 +** made NULL or made to point to memory obtained from [sqlite3_malloc]
1.4693 +** or else the use of the [temp_store_directory pragma] should be avoided.
1.4694 +**
1.4695 +** <b>Note to Windows Runtime users:</b> The temporary directory must be set
1.4696 +** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
1.4697 +** features that require the use of temporary files may fail. Here is an
1.4698 +** example of how to do this using C++ with the Windows Runtime:
1.4699 +**
1.4700 +** <blockquote><pre>
1.4701 +** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
1.4702 +** TemporaryFolder->Path->Data();
1.4703 +** char zPathBuf[MAX_PATH + 1];
1.4704 +** memset(zPathBuf, 0, sizeof(zPathBuf));
1.4705 +** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
1.4706 +** NULL, NULL);
1.4707 +** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
1.4708 +** </pre></blockquote>
1.4709 +*/
1.4710 +SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
1.4711 +
1.4712 +/*
1.4713 +** CAPI3REF: Name Of The Folder Holding Database Files
1.4714 +**
1.4715 +** ^(If this global variable is made to point to a string which is
1.4716 +** the name of a folder (a.k.a. directory), then all database files
1.4717 +** specified with a relative pathname and created or accessed by
1.4718 +** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
1.4719 +** to be relative to that directory.)^ ^If this variable is a NULL
1.4720 +** pointer, then SQLite assumes that all database files specified
1.4721 +** with a relative pathname are relative to the current directory
1.4722 +** for the process. Only the windows VFS makes use of this global
1.4723 +** variable; it is ignored by the unix VFS.
1.4724 +**
1.4725 +** Changing the value of this variable while a database connection is
1.4726 +** open can result in a corrupt database.
1.4727 +**
1.4728 +** It is not safe to read or modify this variable in more than one
1.4729 +** thread at a time. It is not safe to read or modify this variable
1.4730 +** if a [database connection] is being used at the same time in a separate
1.4731 +** thread.
1.4732 +** It is intended that this variable be set once
1.4733 +** as part of process initialization and before any SQLite interface
1.4734 +** routines have been called and that this variable remain unchanged
1.4735 +** thereafter.
1.4736 +**
1.4737 +** ^The [data_store_directory pragma] may modify this variable and cause
1.4738 +** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
1.4739 +** the [data_store_directory pragma] always assumes that any string
1.4740 +** that this variable points to is held in memory obtained from
1.4741 +** [sqlite3_malloc] and the pragma may attempt to free that memory
1.4742 +** using [sqlite3_free].
1.4743 +** Hence, if this variable is modified directly, either it should be
1.4744 +** made NULL or made to point to memory obtained from [sqlite3_malloc]
1.4745 +** or else the use of the [data_store_directory pragma] should be avoided.
1.4746 +*/
1.4747 +SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
1.4748 +
1.4749 +/*
1.4750 +** CAPI3REF: Test For Auto-Commit Mode
1.4751 +** KEYWORDS: {autocommit mode}
1.4752 +**
1.4753 +** ^The sqlite3_get_autocommit() interface returns non-zero or
1.4754 +** zero if the given database connection is or is not in autocommit mode,
1.4755 +** respectively. ^Autocommit mode is on by default.
1.4756 +** ^Autocommit mode is disabled by a [BEGIN] statement.
1.4757 +** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
1.4758 +**
1.4759 +** If certain kinds of errors occur on a statement within a multi-statement
1.4760 +** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
1.4761 +** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
1.4762 +** transaction might be rolled back automatically. The only way to
1.4763 +** find out whether SQLite automatically rolled back the transaction after
1.4764 +** an error is to use this function.
1.4765 +**
1.4766 +** If another thread changes the autocommit status of the database
1.4767 +** connection while this routine is running, then the return value
1.4768 +** is undefined.
1.4769 +*/
1.4770 +SQLITE_API int sqlite3_get_autocommit(sqlite3*);
1.4771 +
1.4772 +/*
1.4773 +** CAPI3REF: Find The Database Handle Of A Prepared Statement
1.4774 +**
1.4775 +** ^The sqlite3_db_handle interface returns the [database connection] handle
1.4776 +** to which a [prepared statement] belongs. ^The [database connection]
1.4777 +** returned by sqlite3_db_handle is the same [database connection]
1.4778 +** that was the first argument
1.4779 +** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
1.4780 +** create the statement in the first place.
1.4781 +*/
1.4782 +SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
1.4783 +
1.4784 +/*
1.4785 +** CAPI3REF: Return The Filename For A Database Connection
1.4786 +**
1.4787 +** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
1.4788 +** associated with database N of connection D. ^The main database file
1.4789 +** has the name "main". If there is no attached database N on the database
1.4790 +** connection D, or if database N is a temporary or in-memory database, then
1.4791 +** a NULL pointer is returned.
1.4792 +**
1.4793 +** ^The filename returned by this function is the output of the
1.4794 +** xFullPathname method of the [VFS]. ^In other words, the filename
1.4795 +** will be an absolute pathname, even if the filename used
1.4796 +** to open the database originally was a URI or relative pathname.
1.4797 +*/
1.4798 +SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
1.4799 +
1.4800 +/*
1.4801 +** CAPI3REF: Determine if a database is read-only
1.4802 +**
1.4803 +** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
1.4804 +** of connection D is read-only, 0 if it is read/write, or -1 if N is not
1.4805 +** the name of a database on connection D.
1.4806 +*/
1.4807 +SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
1.4808 +
1.4809 +/*
1.4810 +** CAPI3REF: Find the next prepared statement
1.4811 +**
1.4812 +** ^This interface returns a pointer to the next [prepared statement] after
1.4813 +** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
1.4814 +** then this interface returns a pointer to the first prepared statement
1.4815 +** associated with the database connection pDb. ^If no prepared statement
1.4816 +** satisfies the conditions of this routine, it returns NULL.
1.4817 +**
1.4818 +** The [database connection] pointer D in a call to
1.4819 +** [sqlite3_next_stmt(D,S)] must refer to an open database
1.4820 +** connection and in particular must not be a NULL pointer.
1.4821 +*/
1.4822 +SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
1.4823 +
1.4824 +/*
1.4825 +** CAPI3REF: Commit And Rollback Notification Callbacks
1.4826 +**
1.4827 +** ^The sqlite3_commit_hook() interface registers a callback
1.4828 +** function to be invoked whenever a transaction is [COMMIT | committed].
1.4829 +** ^Any callback set by a previous call to sqlite3_commit_hook()
1.4830 +** for the same database connection is overridden.
1.4831 +** ^The sqlite3_rollback_hook() interface registers a callback
1.4832 +** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
1.4833 +** ^Any callback set by a previous call to sqlite3_rollback_hook()
1.4834 +** for the same database connection is overridden.
1.4835 +** ^The pArg argument is passed through to the callback.
1.4836 +** ^If the callback on a commit hook function returns non-zero,
1.4837 +** then the commit is converted into a rollback.
1.4838 +**
1.4839 +** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
1.4840 +** return the P argument from the previous call of the same function
1.4841 +** on the same [database connection] D, or NULL for
1.4842 +** the first call for each function on D.
1.4843 +**
1.4844 +** The commit and rollback hook callbacks are not reentrant.
1.4845 +** The callback implementation must not do anything that will modify
1.4846 +** the database connection that invoked the callback. Any actions
1.4847 +** to modify the database connection must be deferred until after the
1.4848 +** completion of the [sqlite3_step()] call that triggered the commit
1.4849 +** or rollback hook in the first place.
1.4850 +** Note that running any other SQL statements, including SELECT statements,
1.4851 +** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
1.4852 +** the database connections for the meaning of "modify" in this paragraph.
1.4853 +**
1.4854 +** ^Registering a NULL function disables the callback.
1.4855 +**
1.4856 +** ^When the commit hook callback routine returns zero, the [COMMIT]
1.4857 +** operation is allowed to continue normally. ^If the commit hook
1.4858 +** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
1.4859 +** ^The rollback hook is invoked on a rollback that results from a commit
1.4860 +** hook returning non-zero, just as it would be with any other rollback.
1.4861 +**
1.4862 +** ^For the purposes of this API, a transaction is said to have been
1.4863 +** rolled back if an explicit "ROLLBACK" statement is executed, or
1.4864 +** an error or constraint causes an implicit rollback to occur.
1.4865 +** ^The rollback callback is not invoked if a transaction is
1.4866 +** automatically rolled back because the database connection is closed.
1.4867 +**
1.4868 +** See also the [sqlite3_update_hook()] interface.
1.4869 +*/
1.4870 +SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
1.4871 +SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
1.4872 +
1.4873 +/*
1.4874 +** CAPI3REF: Data Change Notification Callbacks
1.4875 +**
1.4876 +** ^The sqlite3_update_hook() interface registers a callback function
1.4877 +** with the [database connection] identified by the first argument
1.4878 +** to be invoked whenever a row is updated, inserted or deleted in
1.4879 +** a rowid table.
1.4880 +** ^Any callback set by a previous call to this function
1.4881 +** for the same database connection is overridden.
1.4882 +**
1.4883 +** ^The second argument is a pointer to the function to invoke when a
1.4884 +** row is updated, inserted or deleted in a rowid table.
1.4885 +** ^The first argument to the callback is a copy of the third argument
1.4886 +** to sqlite3_update_hook().
1.4887 +** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
1.4888 +** or [SQLITE_UPDATE], depending on the operation that caused the callback
1.4889 +** to be invoked.
1.4890 +** ^The third and fourth arguments to the callback contain pointers to the
1.4891 +** database and table name containing the affected row.
1.4892 +** ^The final callback parameter is the [rowid] of the row.
1.4893 +** ^In the case of an update, this is the [rowid] after the update takes place.
1.4894 +**
1.4895 +** ^(The update hook is not invoked when internal system tables are
1.4896 +** modified (i.e. sqlite_master and sqlite_sequence).)^
1.4897 +** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
1.4898 +**
1.4899 +** ^In the current implementation, the update hook
1.4900 +** is not invoked when duplication rows are deleted because of an
1.4901 +** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
1.4902 +** invoked when rows are deleted using the [truncate optimization].
1.4903 +** The exceptions defined in this paragraph might change in a future
1.4904 +** release of SQLite.
1.4905 +**
1.4906 +** The update hook implementation must not do anything that will modify
1.4907 +** the database connection that invoked the update hook. Any actions
1.4908 +** to modify the database connection must be deferred until after the
1.4909 +** completion of the [sqlite3_step()] call that triggered the update hook.
1.4910 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
1.4911 +** database connections for the meaning of "modify" in this paragraph.
1.4912 +**
1.4913 +** ^The sqlite3_update_hook(D,C,P) function
1.4914 +** returns the P argument from the previous call
1.4915 +** on the same [database connection] D, or NULL for
1.4916 +** the first call on D.
1.4917 +**
1.4918 +** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
1.4919 +** interfaces.
1.4920 +*/
1.4921 +SQLITE_API void *sqlite3_update_hook(
1.4922 + sqlite3*,
1.4923 + void(*)(void *,int ,char const *,char const *,sqlite3_int64),
1.4924 + void*
1.4925 +);
1.4926 +
1.4927 +/*
1.4928 +** CAPI3REF: Enable Or Disable Shared Pager Cache
1.4929 +**
1.4930 +** ^(This routine enables or disables the sharing of the database cache
1.4931 +** and schema data structures between [database connection | connections]
1.4932 +** to the same database. Sharing is enabled if the argument is true
1.4933 +** and disabled if the argument is false.)^
1.4934 +**
1.4935 +** ^Cache sharing is enabled and disabled for an entire process.
1.4936 +** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
1.4937 +** sharing was enabled or disabled for each thread separately.
1.4938 +**
1.4939 +** ^(The cache sharing mode set by this interface effects all subsequent
1.4940 +** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
1.4941 +** Existing database connections continue use the sharing mode
1.4942 +** that was in effect at the time they were opened.)^
1.4943 +**
1.4944 +** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
1.4945 +** successfully. An [error code] is returned otherwise.)^
1.4946 +**
1.4947 +** ^Shared cache is disabled by default. But this might change in
1.4948 +** future releases of SQLite. Applications that care about shared
1.4949 +** cache setting should set it explicitly.
1.4950 +**
1.4951 +** This interface is threadsafe on processors where writing a
1.4952 +** 32-bit integer is atomic.
1.4953 +**
1.4954 +** See Also: [SQLite Shared-Cache Mode]
1.4955 +*/
1.4956 +SQLITE_API int sqlite3_enable_shared_cache(int);
1.4957 +
1.4958 +/*
1.4959 +** CAPI3REF: Attempt To Free Heap Memory
1.4960 +**
1.4961 +** ^The sqlite3_release_memory() interface attempts to free N bytes
1.4962 +** of heap memory by deallocating non-essential memory allocations
1.4963 +** held by the database library. Memory used to cache database
1.4964 +** pages to improve performance is an example of non-essential memory.
1.4965 +** ^sqlite3_release_memory() returns the number of bytes actually freed,
1.4966 +** which might be more or less than the amount requested.
1.4967 +** ^The sqlite3_release_memory() routine is a no-op returning zero
1.4968 +** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
1.4969 +**
1.4970 +** See also: [sqlite3_db_release_memory()]
1.4971 +*/
1.4972 +SQLITE_API int sqlite3_release_memory(int);
1.4973 +
1.4974 +/*
1.4975 +** CAPI3REF: Free Memory Used By A Database Connection
1.4976 +**
1.4977 +** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
1.4978 +** memory as possible from database connection D. Unlike the
1.4979 +** [sqlite3_release_memory()] interface, this interface is in effect even
1.4980 +** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
1.4981 +** omitted.
1.4982 +**
1.4983 +** See also: [sqlite3_release_memory()]
1.4984 +*/
1.4985 +SQLITE_API int sqlite3_db_release_memory(sqlite3*);
1.4986 +
1.4987 +/*
1.4988 +** CAPI3REF: Impose A Limit On Heap Size
1.4989 +**
1.4990 +** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
1.4991 +** soft limit on the amount of heap memory that may be allocated by SQLite.
1.4992 +** ^SQLite strives to keep heap memory utilization below the soft heap
1.4993 +** limit by reducing the number of pages held in the page cache
1.4994 +** as heap memory usages approaches the limit.
1.4995 +** ^The soft heap limit is "soft" because even though SQLite strives to stay
1.4996 +** below the limit, it will exceed the limit rather than generate
1.4997 +** an [SQLITE_NOMEM] error. In other words, the soft heap limit
1.4998 +** is advisory only.
1.4999 +**
1.5000 +** ^The return value from sqlite3_soft_heap_limit64() is the size of
1.5001 +** the soft heap limit prior to the call, or negative in the case of an
1.5002 +** error. ^If the argument N is negative
1.5003 +** then no change is made to the soft heap limit. Hence, the current
1.5004 +** size of the soft heap limit can be determined by invoking
1.5005 +** sqlite3_soft_heap_limit64() with a negative argument.
1.5006 +**
1.5007 +** ^If the argument N is zero then the soft heap limit is disabled.
1.5008 +**
1.5009 +** ^(The soft heap limit is not enforced in the current implementation
1.5010 +** if one or more of following conditions are true:
1.5011 +**
1.5012 +** <ul>
1.5013 +** <li> The soft heap limit is set to zero.
1.5014 +** <li> Memory accounting is disabled using a combination of the
1.5015 +** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
1.5016 +** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
1.5017 +** <li> An alternative page cache implementation is specified using
1.5018 +** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
1.5019 +** <li> The page cache allocates from its own memory pool supplied
1.5020 +** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
1.5021 +** from the heap.
1.5022 +** </ul>)^
1.5023 +**
1.5024 +** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
1.5025 +** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
1.5026 +** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
1.5027 +** the soft heap limit is enforced on every memory allocation. Without
1.5028 +** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
1.5029 +** when memory is allocated by the page cache. Testing suggests that because
1.5030 +** the page cache is the predominate memory user in SQLite, most
1.5031 +** applications will achieve adequate soft heap limit enforcement without
1.5032 +** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
1.5033 +**
1.5034 +** The circumstances under which SQLite will enforce the soft heap limit may
1.5035 +** changes in future releases of SQLite.
1.5036 +*/
1.5037 +SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
1.5038 +
1.5039 +/*
1.5040 +** CAPI3REF: Deprecated Soft Heap Limit Interface
1.5041 +** DEPRECATED
1.5042 +**
1.5043 +** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
1.5044 +** interface. This routine is provided for historical compatibility
1.5045 +** only. All new applications should use the
1.5046 +** [sqlite3_soft_heap_limit64()] interface rather than this one.
1.5047 +*/
1.5048 +SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
1.5049 +
1.5050 +
1.5051 +/*
1.5052 +** CAPI3REF: Extract Metadata About A Column Of A Table
1.5053 +**
1.5054 +** ^This routine returns metadata about a specific column of a specific
1.5055 +** database table accessible using the [database connection] handle
1.5056 +** passed as the first function argument.
1.5057 +**
1.5058 +** ^The column is identified by the second, third and fourth parameters to
1.5059 +** this function. ^The second parameter is either the name of the database
1.5060 +** (i.e. "main", "temp", or an attached database) containing the specified
1.5061 +** table or NULL. ^If it is NULL, then all attached databases are searched
1.5062 +** for the table using the same algorithm used by the database engine to
1.5063 +** resolve unqualified table references.
1.5064 +**
1.5065 +** ^The third and fourth parameters to this function are the table and column
1.5066 +** name of the desired column, respectively. Neither of these parameters
1.5067 +** may be NULL.
1.5068 +**
1.5069 +** ^Metadata is returned by writing to the memory locations passed as the 5th
1.5070 +** and subsequent parameters to this function. ^Any of these arguments may be
1.5071 +** NULL, in which case the corresponding element of metadata is omitted.
1.5072 +**
1.5073 +** ^(<blockquote>
1.5074 +** <table border="1">
1.5075 +** <tr><th> Parameter <th> Output<br>Type <th> Description
1.5076 +**
1.5077 +** <tr><td> 5th <td> const char* <td> Data type
1.5078 +** <tr><td> 6th <td> const char* <td> Name of default collation sequence
1.5079 +** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
1.5080 +** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
1.5081 +** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
1.5082 +** </table>
1.5083 +** </blockquote>)^
1.5084 +**
1.5085 +** ^The memory pointed to by the character pointers returned for the
1.5086 +** declaration type and collation sequence is valid only until the next
1.5087 +** call to any SQLite API function.
1.5088 +**
1.5089 +** ^If the specified table is actually a view, an [error code] is returned.
1.5090 +**
1.5091 +** ^If the specified column is "rowid", "oid" or "_rowid_" and an
1.5092 +** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
1.5093 +** parameters are set for the explicitly declared column. ^(If there is no
1.5094 +** explicitly declared [INTEGER PRIMARY KEY] column, then the output
1.5095 +** parameters are set as follows:
1.5096 +**
1.5097 +** <pre>
1.5098 +** data type: "INTEGER"
1.5099 +** collation sequence: "BINARY"
1.5100 +** not null: 0
1.5101 +** primary key: 1
1.5102 +** auto increment: 0
1.5103 +** </pre>)^
1.5104 +**
1.5105 +** ^(This function may load one or more schemas from database files. If an
1.5106 +** error occurs during this process, or if the requested table or column
1.5107 +** cannot be found, an [error code] is returned and an error message left
1.5108 +** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
1.5109 +**
1.5110 +** ^This API is only available if the library was compiled with the
1.5111 +** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
1.5112 +*/
1.5113 +SQLITE_API int sqlite3_table_column_metadata(
1.5114 + sqlite3 *db, /* Connection handle */
1.5115 + const char *zDbName, /* Database name or NULL */
1.5116 + const char *zTableName, /* Table name */
1.5117 + const char *zColumnName, /* Column name */
1.5118 + char const **pzDataType, /* OUTPUT: Declared data type */
1.5119 + char const **pzCollSeq, /* OUTPUT: Collation sequence name */
1.5120 + int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
1.5121 + int *pPrimaryKey, /* OUTPUT: True if column part of PK */
1.5122 + int *pAutoinc /* OUTPUT: True if column is auto-increment */
1.5123 +);
1.5124 +
1.5125 +/*
1.5126 +** CAPI3REF: Load An Extension
1.5127 +**
1.5128 +** ^This interface loads an SQLite extension library from the named file.
1.5129 +**
1.5130 +** ^The sqlite3_load_extension() interface attempts to load an
1.5131 +** [SQLite extension] library contained in the file zFile. If
1.5132 +** the file cannot be loaded directly, attempts are made to load
1.5133 +** with various operating-system specific extensions added.
1.5134 +** So for example, if "samplelib" cannot be loaded, then names like
1.5135 +** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
1.5136 +** be tried also.
1.5137 +**
1.5138 +** ^The entry point is zProc.
1.5139 +** ^(zProc may be 0, in which case SQLite will try to come up with an
1.5140 +** entry point name on its own. It first tries "sqlite3_extension_init".
1.5141 +** If that does not work, it constructs a name "sqlite3_X_init" where the
1.5142 +** X is consists of the lower-case equivalent of all ASCII alphabetic
1.5143 +** characters in the filename from the last "/" to the first following
1.5144 +** "." and omitting any initial "lib".)^
1.5145 +** ^The sqlite3_load_extension() interface returns
1.5146 +** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
1.5147 +** ^If an error occurs and pzErrMsg is not 0, then the
1.5148 +** [sqlite3_load_extension()] interface shall attempt to
1.5149 +** fill *pzErrMsg with error message text stored in memory
1.5150 +** obtained from [sqlite3_malloc()]. The calling function
1.5151 +** should free this memory by calling [sqlite3_free()].
1.5152 +**
1.5153 +** ^Extension loading must be enabled using
1.5154 +** [sqlite3_enable_load_extension()] prior to calling this API,
1.5155 +** otherwise an error will be returned.
1.5156 +**
1.5157 +** See also the [load_extension() SQL function].
1.5158 +*/
1.5159 +SQLITE_API int sqlite3_load_extension(
1.5160 + sqlite3 *db, /* Load the extension into this database connection */
1.5161 + const char *zFile, /* Name of the shared library containing extension */
1.5162 + const char *zProc, /* Entry point. Derived from zFile if 0 */
1.5163 + char **pzErrMsg /* Put error message here if not 0 */
1.5164 +);
1.5165 +
1.5166 +/*
1.5167 +** CAPI3REF: Enable Or Disable Extension Loading
1.5168 +**
1.5169 +** ^So as not to open security holes in older applications that are
1.5170 +** unprepared to deal with [extension loading], and as a means of disabling
1.5171 +** [extension loading] while evaluating user-entered SQL, the following API
1.5172 +** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
1.5173 +**
1.5174 +** ^Extension loading is off by default.
1.5175 +** ^Call the sqlite3_enable_load_extension() routine with onoff==1
1.5176 +** to turn extension loading on and call it with onoff==0 to turn
1.5177 +** it back off again.
1.5178 +*/
1.5179 +SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
1.5180 +
1.5181 +/*
1.5182 +** CAPI3REF: Automatically Load Statically Linked Extensions
1.5183 +**
1.5184 +** ^This interface causes the xEntryPoint() function to be invoked for
1.5185 +** each new [database connection] that is created. The idea here is that
1.5186 +** xEntryPoint() is the entry point for a statically linked [SQLite extension]
1.5187 +** that is to be automatically loaded into all new database connections.
1.5188 +**
1.5189 +** ^(Even though the function prototype shows that xEntryPoint() takes
1.5190 +** no arguments and returns void, SQLite invokes xEntryPoint() with three
1.5191 +** arguments and expects and integer result as if the signature of the
1.5192 +** entry point where as follows:
1.5193 +**
1.5194 +** <blockquote><pre>
1.5195 +** int xEntryPoint(
1.5196 +** sqlite3 *db,
1.5197 +** const char **pzErrMsg,
1.5198 +** const struct sqlite3_api_routines *pThunk
1.5199 +** );
1.5200 +** </pre></blockquote>)^
1.5201 +**
1.5202 +** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
1.5203 +** point to an appropriate error message (obtained from [sqlite3_mprintf()])
1.5204 +** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
1.5205 +** is NULL before calling the xEntryPoint(). ^SQLite will invoke
1.5206 +** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
1.5207 +** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
1.5208 +** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
1.5209 +**
1.5210 +** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
1.5211 +** on the list of automatic extensions is a harmless no-op. ^No entry point
1.5212 +** will be called more than once for each database connection that is opened.
1.5213 +**
1.5214 +** See also: [sqlite3_reset_auto_extension()]
1.5215 +** and [sqlite3_cancel_auto_extension()]
1.5216 +*/
1.5217 +SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
1.5218 +
1.5219 +/*
1.5220 +** CAPI3REF: Cancel Automatic Extension Loading
1.5221 +**
1.5222 +** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
1.5223 +** initialization routine X that was registered using a prior call to
1.5224 +** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
1.5225 +** routine returns 1 if initialization routine X was successfully
1.5226 +** unregistered and it returns 0 if X was not on the list of initialization
1.5227 +** routines.
1.5228 +*/
1.5229 +SQLITE_API int sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
1.5230 +
1.5231 +/*
1.5232 +** CAPI3REF: Reset Automatic Extension Loading
1.5233 +**
1.5234 +** ^This interface disables all automatic extensions previously
1.5235 +** registered using [sqlite3_auto_extension()].
1.5236 +*/
1.5237 +SQLITE_API void sqlite3_reset_auto_extension(void);
1.5238 +
1.5239 +/*
1.5240 +** The interface to the virtual-table mechanism is currently considered
1.5241 +** to be experimental. The interface might change in incompatible ways.
1.5242 +** If this is a problem for you, do not use the interface at this time.
1.5243 +**
1.5244 +** When the virtual-table mechanism stabilizes, we will declare the
1.5245 +** interface fixed, support it indefinitely, and remove this comment.
1.5246 +*/
1.5247 +
1.5248 +/*
1.5249 +** Structures used by the virtual table interface
1.5250 +*/
1.5251 +typedef struct sqlite3_vtab sqlite3_vtab;
1.5252 +typedef struct sqlite3_index_info sqlite3_index_info;
1.5253 +typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
1.5254 +typedef struct sqlite3_module sqlite3_module;
1.5255 +
1.5256 +/*
1.5257 +** CAPI3REF: Virtual Table Object
1.5258 +** KEYWORDS: sqlite3_module {virtual table module}
1.5259 +**
1.5260 +** This structure, sometimes called a "virtual table module",
1.5261 +** defines the implementation of a [virtual tables].
1.5262 +** This structure consists mostly of methods for the module.
1.5263 +**
1.5264 +** ^A virtual table module is created by filling in a persistent
1.5265 +** instance of this structure and passing a pointer to that instance
1.5266 +** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
1.5267 +** ^The registration remains valid until it is replaced by a different
1.5268 +** module or until the [database connection] closes. The content
1.5269 +** of this structure must not change while it is registered with
1.5270 +** any database connection.
1.5271 +*/
1.5272 +struct sqlite3_module {
1.5273 + int iVersion;
1.5274 + int (*xCreate)(sqlite3*, void *pAux,
1.5275 + int argc, const char *const*argv,
1.5276 + sqlite3_vtab **ppVTab, char**);
1.5277 + int (*xConnect)(sqlite3*, void *pAux,
1.5278 + int argc, const char *const*argv,
1.5279 + sqlite3_vtab **ppVTab, char**);
1.5280 + int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
1.5281 + int (*xDisconnect)(sqlite3_vtab *pVTab);
1.5282 + int (*xDestroy)(sqlite3_vtab *pVTab);
1.5283 + int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
1.5284 + int (*xClose)(sqlite3_vtab_cursor*);
1.5285 + int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
1.5286 + int argc, sqlite3_value **argv);
1.5287 + int (*xNext)(sqlite3_vtab_cursor*);
1.5288 + int (*xEof)(sqlite3_vtab_cursor*);
1.5289 + int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
1.5290 + int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
1.5291 + int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
1.5292 + int (*xBegin)(sqlite3_vtab *pVTab);
1.5293 + int (*xSync)(sqlite3_vtab *pVTab);
1.5294 + int (*xCommit)(sqlite3_vtab *pVTab);
1.5295 + int (*xRollback)(sqlite3_vtab *pVTab);
1.5296 + int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
1.5297 + void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
1.5298 + void **ppArg);
1.5299 + int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
1.5300 + /* The methods above are in version 1 of the sqlite_module object. Those
1.5301 + ** below are for version 2 and greater. */
1.5302 + int (*xSavepoint)(sqlite3_vtab *pVTab, int);
1.5303 + int (*xRelease)(sqlite3_vtab *pVTab, int);
1.5304 + int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
1.5305 +};
1.5306 +
1.5307 +/*
1.5308 +** CAPI3REF: Virtual Table Indexing Information
1.5309 +** KEYWORDS: sqlite3_index_info
1.5310 +**
1.5311 +** The sqlite3_index_info structure and its substructures is used as part
1.5312 +** of the [virtual table] interface to
1.5313 +** pass information into and receive the reply from the [xBestIndex]
1.5314 +** method of a [virtual table module]. The fields under **Inputs** are the
1.5315 +** inputs to xBestIndex and are read-only. xBestIndex inserts its
1.5316 +** results into the **Outputs** fields.
1.5317 +**
1.5318 +** ^(The aConstraint[] array records WHERE clause constraints of the form:
1.5319 +**
1.5320 +** <blockquote>column OP expr</blockquote>
1.5321 +**
1.5322 +** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
1.5323 +** stored in aConstraint[].op using one of the
1.5324 +** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
1.5325 +** ^(The index of the column is stored in
1.5326 +** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
1.5327 +** expr on the right-hand side can be evaluated (and thus the constraint
1.5328 +** is usable) and false if it cannot.)^
1.5329 +**
1.5330 +** ^The optimizer automatically inverts terms of the form "expr OP column"
1.5331 +** and makes other simplifications to the WHERE clause in an attempt to
1.5332 +** get as many WHERE clause terms into the form shown above as possible.
1.5333 +** ^The aConstraint[] array only reports WHERE clause terms that are
1.5334 +** relevant to the particular virtual table being queried.
1.5335 +**
1.5336 +** ^Information about the ORDER BY clause is stored in aOrderBy[].
1.5337 +** ^Each term of aOrderBy records a column of the ORDER BY clause.
1.5338 +**
1.5339 +** The [xBestIndex] method must fill aConstraintUsage[] with information
1.5340 +** about what parameters to pass to xFilter. ^If argvIndex>0 then
1.5341 +** the right-hand side of the corresponding aConstraint[] is evaluated
1.5342 +** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
1.5343 +** is true, then the constraint is assumed to be fully handled by the
1.5344 +** virtual table and is not checked again by SQLite.)^
1.5345 +**
1.5346 +** ^The idxNum and idxPtr values are recorded and passed into the
1.5347 +** [xFilter] method.
1.5348 +** ^[sqlite3_free()] is used to free idxPtr if and only if
1.5349 +** needToFreeIdxPtr is true.
1.5350 +**
1.5351 +** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
1.5352 +** the correct order to satisfy the ORDER BY clause so that no separate
1.5353 +** sorting step is required.
1.5354 +**
1.5355 +** ^The estimatedCost value is an estimate of the cost of a particular
1.5356 +** strategy. A cost of N indicates that the cost of the strategy is similar
1.5357 +** to a linear scan of an SQLite table with N rows. A cost of log(N)
1.5358 +** indicates that the expense of the operation is similar to that of a
1.5359 +** binary search on a unique indexed field of an SQLite table with N rows.
1.5360 +**
1.5361 +** ^The estimatedRows value is an estimate of the number of rows that
1.5362 +** will be returned by the strategy.
1.5363 +**
1.5364 +** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
1.5365 +** structure for SQLite version 3.8.2. If a virtual table extension is
1.5366 +** used with an SQLite version earlier than 3.8.2, the results of attempting
1.5367 +** to read or write the estimatedRows field are undefined (but are likely
1.5368 +** to included crashing the application). The estimatedRows field should
1.5369 +** therefore only be used if [sqlite3_libversion_number()] returns a
1.5370 +** value greater than or equal to 3008002.
1.5371 +*/
1.5372 +struct sqlite3_index_info {
1.5373 + /* Inputs */
1.5374 + int nConstraint; /* Number of entries in aConstraint */
1.5375 + struct sqlite3_index_constraint {
1.5376 + int iColumn; /* Column on left-hand side of constraint */
1.5377 + unsigned char op; /* Constraint operator */
1.5378 + unsigned char usable; /* True if this constraint is usable */
1.5379 + int iTermOffset; /* Used internally - xBestIndex should ignore */
1.5380 + } *aConstraint; /* Table of WHERE clause constraints */
1.5381 + int nOrderBy; /* Number of terms in the ORDER BY clause */
1.5382 + struct sqlite3_index_orderby {
1.5383 + int iColumn; /* Column number */
1.5384 + unsigned char desc; /* True for DESC. False for ASC. */
1.5385 + } *aOrderBy; /* The ORDER BY clause */
1.5386 + /* Outputs */
1.5387 + struct sqlite3_index_constraint_usage {
1.5388 + int argvIndex; /* if >0, constraint is part of argv to xFilter */
1.5389 + unsigned char omit; /* Do not code a test for this constraint */
1.5390 + } *aConstraintUsage;
1.5391 + int idxNum; /* Number used to identify the index */
1.5392 + char *idxStr; /* String, possibly obtained from sqlite3_malloc */
1.5393 + int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
1.5394 + int orderByConsumed; /* True if output is already ordered */
1.5395 + double estimatedCost; /* Estimated cost of using this index */
1.5396 + /* Fields below are only available in SQLite 3.8.2 and later */
1.5397 + sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
1.5398 +};
1.5399 +
1.5400 +/*
1.5401 +** CAPI3REF: Virtual Table Constraint Operator Codes
1.5402 +**
1.5403 +** These macros defined the allowed values for the
1.5404 +** [sqlite3_index_info].aConstraint[].op field. Each value represents
1.5405 +** an operator that is part of a constraint term in the wHERE clause of
1.5406 +** a query that uses a [virtual table].
1.5407 +*/
1.5408 +#define SQLITE_INDEX_CONSTRAINT_EQ 2
1.5409 +#define SQLITE_INDEX_CONSTRAINT_GT 4
1.5410 +#define SQLITE_INDEX_CONSTRAINT_LE 8
1.5411 +#define SQLITE_INDEX_CONSTRAINT_LT 16
1.5412 +#define SQLITE_INDEX_CONSTRAINT_GE 32
1.5413 +#define SQLITE_INDEX_CONSTRAINT_MATCH 64
1.5414 +
1.5415 +/*
1.5416 +** CAPI3REF: Register A Virtual Table Implementation
1.5417 +**
1.5418 +** ^These routines are used to register a new [virtual table module] name.
1.5419 +** ^Module names must be registered before
1.5420 +** creating a new [virtual table] using the module and before using a
1.5421 +** preexisting [virtual table] for the module.
1.5422 +**
1.5423 +** ^The module name is registered on the [database connection] specified
1.5424 +** by the first parameter. ^The name of the module is given by the
1.5425 +** second parameter. ^The third parameter is a pointer to
1.5426 +** the implementation of the [virtual table module]. ^The fourth
1.5427 +** parameter is an arbitrary client data pointer that is passed through
1.5428 +** into the [xCreate] and [xConnect] methods of the virtual table module
1.5429 +** when a new virtual table is be being created or reinitialized.
1.5430 +**
1.5431 +** ^The sqlite3_create_module_v2() interface has a fifth parameter which
1.5432 +** is a pointer to a destructor for the pClientData. ^SQLite will
1.5433 +** invoke the destructor function (if it is not NULL) when SQLite
1.5434 +** no longer needs the pClientData pointer. ^The destructor will also
1.5435 +** be invoked if the call to sqlite3_create_module_v2() fails.
1.5436 +** ^The sqlite3_create_module()
1.5437 +** interface is equivalent to sqlite3_create_module_v2() with a NULL
1.5438 +** destructor.
1.5439 +*/
1.5440 +SQLITE_API int sqlite3_create_module(
1.5441 + sqlite3 *db, /* SQLite connection to register module with */
1.5442 + const char *zName, /* Name of the module */
1.5443 + const sqlite3_module *p, /* Methods for the module */
1.5444 + void *pClientData /* Client data for xCreate/xConnect */
1.5445 +);
1.5446 +SQLITE_API int sqlite3_create_module_v2(
1.5447 + sqlite3 *db, /* SQLite connection to register module with */
1.5448 + const char *zName, /* Name of the module */
1.5449 + const sqlite3_module *p, /* Methods for the module */
1.5450 + void *pClientData, /* Client data for xCreate/xConnect */
1.5451 + void(*xDestroy)(void*) /* Module destructor function */
1.5452 +);
1.5453 +
1.5454 +/*
1.5455 +** CAPI3REF: Virtual Table Instance Object
1.5456 +** KEYWORDS: sqlite3_vtab
1.5457 +**
1.5458 +** Every [virtual table module] implementation uses a subclass
1.5459 +** of this object to describe a particular instance
1.5460 +** of the [virtual table]. Each subclass will
1.5461 +** be tailored to the specific needs of the module implementation.
1.5462 +** The purpose of this superclass is to define certain fields that are
1.5463 +** common to all module implementations.
1.5464 +**
1.5465 +** ^Virtual tables methods can set an error message by assigning a
1.5466 +** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
1.5467 +** take care that any prior string is freed by a call to [sqlite3_free()]
1.5468 +** prior to assigning a new string to zErrMsg. ^After the error message
1.5469 +** is delivered up to the client application, the string will be automatically
1.5470 +** freed by sqlite3_free() and the zErrMsg field will be zeroed.
1.5471 +*/
1.5472 +struct sqlite3_vtab {
1.5473 + const sqlite3_module *pModule; /* The module for this virtual table */
1.5474 + int nRef; /* NO LONGER USED */
1.5475 + char *zErrMsg; /* Error message from sqlite3_mprintf() */
1.5476 + /* Virtual table implementations will typically add additional fields */
1.5477 +};
1.5478 +
1.5479 +/*
1.5480 +** CAPI3REF: Virtual Table Cursor Object
1.5481 +** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
1.5482 +**
1.5483 +** Every [virtual table module] implementation uses a subclass of the
1.5484 +** following structure to describe cursors that point into the
1.5485 +** [virtual table] and are used
1.5486 +** to loop through the virtual table. Cursors are created using the
1.5487 +** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
1.5488 +** by the [sqlite3_module.xClose | xClose] method. Cursors are used
1.5489 +** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
1.5490 +** of the module. Each module implementation will define
1.5491 +** the content of a cursor structure to suit its own needs.
1.5492 +**
1.5493 +** This superclass exists in order to define fields of the cursor that
1.5494 +** are common to all implementations.
1.5495 +*/
1.5496 +struct sqlite3_vtab_cursor {
1.5497 + sqlite3_vtab *pVtab; /* Virtual table of this cursor */
1.5498 + /* Virtual table implementations will typically add additional fields */
1.5499 +};
1.5500 +
1.5501 +/*
1.5502 +** CAPI3REF: Declare The Schema Of A Virtual Table
1.5503 +**
1.5504 +** ^The [xCreate] and [xConnect] methods of a
1.5505 +** [virtual table module] call this interface
1.5506 +** to declare the format (the names and datatypes of the columns) of
1.5507 +** the virtual tables they implement.
1.5508 +*/
1.5509 +SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
1.5510 +
1.5511 +/*
1.5512 +** CAPI3REF: Overload A Function For A Virtual Table
1.5513 +**
1.5514 +** ^(Virtual tables can provide alternative implementations of functions
1.5515 +** using the [xFindFunction] method of the [virtual table module].
1.5516 +** But global versions of those functions
1.5517 +** must exist in order to be overloaded.)^
1.5518 +**
1.5519 +** ^(This API makes sure a global version of a function with a particular
1.5520 +** name and number of parameters exists. If no such function exists
1.5521 +** before this API is called, a new function is created.)^ ^The implementation
1.5522 +** of the new function always causes an exception to be thrown. So
1.5523 +** the new function is not good for anything by itself. Its only
1.5524 +** purpose is to be a placeholder function that can be overloaded
1.5525 +** by a [virtual table].
1.5526 +*/
1.5527 +SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
1.5528 +
1.5529 +/*
1.5530 +** The interface to the virtual-table mechanism defined above (back up
1.5531 +** to a comment remarkably similar to this one) is currently considered
1.5532 +** to be experimental. The interface might change in incompatible ways.
1.5533 +** If this is a problem for you, do not use the interface at this time.
1.5534 +**
1.5535 +** When the virtual-table mechanism stabilizes, we will declare the
1.5536 +** interface fixed, support it indefinitely, and remove this comment.
1.5537 +*/
1.5538 +
1.5539 +/*
1.5540 +** CAPI3REF: A Handle To An Open BLOB
1.5541 +** KEYWORDS: {BLOB handle} {BLOB handles}
1.5542 +**
1.5543 +** An instance of this object represents an open BLOB on which
1.5544 +** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
1.5545 +** ^Objects of this type are created by [sqlite3_blob_open()]
1.5546 +** and destroyed by [sqlite3_blob_close()].
1.5547 +** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
1.5548 +** can be used to read or write small subsections of the BLOB.
1.5549 +** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
1.5550 +*/
1.5551 +typedef struct sqlite3_blob sqlite3_blob;
1.5552 +
1.5553 +/*
1.5554 +** CAPI3REF: Open A BLOB For Incremental I/O
1.5555 +**
1.5556 +** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
1.5557 +** in row iRow, column zColumn, table zTable in database zDb;
1.5558 +** in other words, the same BLOB that would be selected by:
1.5559 +**
1.5560 +** <pre>
1.5561 +** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
1.5562 +** </pre>)^
1.5563 +**
1.5564 +** ^If the flags parameter is non-zero, then the BLOB is opened for read
1.5565 +** and write access. ^If it is zero, the BLOB is opened for read access.
1.5566 +** ^It is not possible to open a column that is part of an index or primary
1.5567 +** key for writing. ^If [foreign key constraints] are enabled, it is
1.5568 +** not possible to open a column that is part of a [child key] for writing.
1.5569 +**
1.5570 +** ^Note that the database name is not the filename that contains
1.5571 +** the database but rather the symbolic name of the database that
1.5572 +** appears after the AS keyword when the database is connected using [ATTACH].
1.5573 +** ^For the main database file, the database name is "main".
1.5574 +** ^For TEMP tables, the database name is "temp".
1.5575 +**
1.5576 +** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
1.5577 +** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
1.5578 +** to be a null pointer.)^
1.5579 +** ^This function sets the [database connection] error code and message
1.5580 +** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
1.5581 +** functions. ^Note that the *ppBlob variable is always initialized in a
1.5582 +** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
1.5583 +** regardless of the success or failure of this routine.
1.5584 +**
1.5585 +** ^(If the row that a BLOB handle points to is modified by an
1.5586 +** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
1.5587 +** then the BLOB handle is marked as "expired".
1.5588 +** This is true if any column of the row is changed, even a column
1.5589 +** other than the one the BLOB handle is open on.)^
1.5590 +** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
1.5591 +** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
1.5592 +** ^(Changes written into a BLOB prior to the BLOB expiring are not
1.5593 +** rolled back by the expiration of the BLOB. Such changes will eventually
1.5594 +** commit if the transaction continues to completion.)^
1.5595 +**
1.5596 +** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
1.5597 +** the opened blob. ^The size of a blob may not be changed by this
1.5598 +** interface. Use the [UPDATE] SQL command to change the size of a
1.5599 +** blob.
1.5600 +**
1.5601 +** ^The [sqlite3_blob_open()] interface will fail for a [WITHOUT ROWID]
1.5602 +** table. Incremental BLOB I/O is not possible on [WITHOUT ROWID] tables.
1.5603 +**
1.5604 +** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
1.5605 +** and the built-in [zeroblob] SQL function can be used, if desired,
1.5606 +** to create an empty, zero-filled blob in which to read or write using
1.5607 +** this interface.
1.5608 +**
1.5609 +** To avoid a resource leak, every open [BLOB handle] should eventually
1.5610 +** be released by a call to [sqlite3_blob_close()].
1.5611 +*/
1.5612 +SQLITE_API int sqlite3_blob_open(
1.5613 + sqlite3*,
1.5614 + const char *zDb,
1.5615 + const char *zTable,
1.5616 + const char *zColumn,
1.5617 + sqlite3_int64 iRow,
1.5618 + int flags,
1.5619 + sqlite3_blob **ppBlob
1.5620 +);
1.5621 +
1.5622 +/*
1.5623 +** CAPI3REF: Move a BLOB Handle to a New Row
1.5624 +**
1.5625 +** ^This function is used to move an existing blob handle so that it points
1.5626 +** to a different row of the same database table. ^The new row is identified
1.5627 +** by the rowid value passed as the second argument. Only the row can be
1.5628 +** changed. ^The database, table and column on which the blob handle is open
1.5629 +** remain the same. Moving an existing blob handle to a new row can be
1.5630 +** faster than closing the existing handle and opening a new one.
1.5631 +**
1.5632 +** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
1.5633 +** it must exist and there must be either a blob or text value stored in
1.5634 +** the nominated column.)^ ^If the new row is not present in the table, or if
1.5635 +** it does not contain a blob or text value, or if another error occurs, an
1.5636 +** SQLite error code is returned and the blob handle is considered aborted.
1.5637 +** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
1.5638 +** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
1.5639 +** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
1.5640 +** always returns zero.
1.5641 +**
1.5642 +** ^This function sets the database handle error code and message.
1.5643 +*/
1.5644 +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
1.5645 +
1.5646 +/*
1.5647 +** CAPI3REF: Close A BLOB Handle
1.5648 +**
1.5649 +** ^Closes an open [BLOB handle].
1.5650 +**
1.5651 +** ^Closing a BLOB shall cause the current transaction to commit
1.5652 +** if there are no other BLOBs, no pending prepared statements, and the
1.5653 +** database connection is in [autocommit mode].
1.5654 +** ^If any writes were made to the BLOB, they might be held in cache
1.5655 +** until the close operation if they will fit.
1.5656 +**
1.5657 +** ^(Closing the BLOB often forces the changes
1.5658 +** out to disk and so if any I/O errors occur, they will likely occur
1.5659 +** at the time when the BLOB is closed. Any errors that occur during
1.5660 +** closing are reported as a non-zero return value.)^
1.5661 +**
1.5662 +** ^(The BLOB is closed unconditionally. Even if this routine returns
1.5663 +** an error code, the BLOB is still closed.)^
1.5664 +**
1.5665 +** ^Calling this routine with a null pointer (such as would be returned
1.5666 +** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
1.5667 +*/
1.5668 +SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
1.5669 +
1.5670 +/*
1.5671 +** CAPI3REF: Return The Size Of An Open BLOB
1.5672 +**
1.5673 +** ^Returns the size in bytes of the BLOB accessible via the
1.5674 +** successfully opened [BLOB handle] in its only argument. ^The
1.5675 +** incremental blob I/O routines can only read or overwriting existing
1.5676 +** blob content; they cannot change the size of a blob.
1.5677 +**
1.5678 +** This routine only works on a [BLOB handle] which has been created
1.5679 +** by a prior successful call to [sqlite3_blob_open()] and which has not
1.5680 +** been closed by [sqlite3_blob_close()]. Passing any other pointer in
1.5681 +** to this routine results in undefined and probably undesirable behavior.
1.5682 +*/
1.5683 +SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
1.5684 +
1.5685 +/*
1.5686 +** CAPI3REF: Read Data From A BLOB Incrementally
1.5687 +**
1.5688 +** ^(This function is used to read data from an open [BLOB handle] into a
1.5689 +** caller-supplied buffer. N bytes of data are copied into buffer Z
1.5690 +** from the open BLOB, starting at offset iOffset.)^
1.5691 +**
1.5692 +** ^If offset iOffset is less than N bytes from the end of the BLOB,
1.5693 +** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
1.5694 +** less than zero, [SQLITE_ERROR] is returned and no data is read.
1.5695 +** ^The size of the blob (and hence the maximum value of N+iOffset)
1.5696 +** can be determined using the [sqlite3_blob_bytes()] interface.
1.5697 +**
1.5698 +** ^An attempt to read from an expired [BLOB handle] fails with an
1.5699 +** error code of [SQLITE_ABORT].
1.5700 +**
1.5701 +** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
1.5702 +** Otherwise, an [error code] or an [extended error code] is returned.)^
1.5703 +**
1.5704 +** This routine only works on a [BLOB handle] which has been created
1.5705 +** by a prior successful call to [sqlite3_blob_open()] and which has not
1.5706 +** been closed by [sqlite3_blob_close()]. Passing any other pointer in
1.5707 +** to this routine results in undefined and probably undesirable behavior.
1.5708 +**
1.5709 +** See also: [sqlite3_blob_write()].
1.5710 +*/
1.5711 +SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
1.5712 +
1.5713 +/*
1.5714 +** CAPI3REF: Write Data Into A BLOB Incrementally
1.5715 +**
1.5716 +** ^This function is used to write data into an open [BLOB handle] from a
1.5717 +** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
1.5718 +** into the open BLOB, starting at offset iOffset.
1.5719 +**
1.5720 +** ^If the [BLOB handle] passed as the first argument was not opened for
1.5721 +** writing (the flags parameter to [sqlite3_blob_open()] was zero),
1.5722 +** this function returns [SQLITE_READONLY].
1.5723 +**
1.5724 +** ^This function may only modify the contents of the BLOB; it is
1.5725 +** not possible to increase the size of a BLOB using this API.
1.5726 +** ^If offset iOffset is less than N bytes from the end of the BLOB,
1.5727 +** [SQLITE_ERROR] is returned and no data is written. ^If N is
1.5728 +** less than zero [SQLITE_ERROR] is returned and no data is written.
1.5729 +** The size of the BLOB (and hence the maximum value of N+iOffset)
1.5730 +** can be determined using the [sqlite3_blob_bytes()] interface.
1.5731 +**
1.5732 +** ^An attempt to write to an expired [BLOB handle] fails with an
1.5733 +** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
1.5734 +** before the [BLOB handle] expired are not rolled back by the
1.5735 +** expiration of the handle, though of course those changes might
1.5736 +** have been overwritten by the statement that expired the BLOB handle
1.5737 +** or by other independent statements.
1.5738 +**
1.5739 +** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
1.5740 +** Otherwise, an [error code] or an [extended error code] is returned.)^
1.5741 +**
1.5742 +** This routine only works on a [BLOB handle] which has been created
1.5743 +** by a prior successful call to [sqlite3_blob_open()] and which has not
1.5744 +** been closed by [sqlite3_blob_close()]. Passing any other pointer in
1.5745 +** to this routine results in undefined and probably undesirable behavior.
1.5746 +**
1.5747 +** See also: [sqlite3_blob_read()].
1.5748 +*/
1.5749 +SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
1.5750 +
1.5751 +/*
1.5752 +** CAPI3REF: Virtual File System Objects
1.5753 +**
1.5754 +** A virtual filesystem (VFS) is an [sqlite3_vfs] object
1.5755 +** that SQLite uses to interact
1.5756 +** with the underlying operating system. Most SQLite builds come with a
1.5757 +** single default VFS that is appropriate for the host computer.
1.5758 +** New VFSes can be registered and existing VFSes can be unregistered.
1.5759 +** The following interfaces are provided.
1.5760 +**
1.5761 +** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
1.5762 +** ^Names are case sensitive.
1.5763 +** ^Names are zero-terminated UTF-8 strings.
1.5764 +** ^If there is no match, a NULL pointer is returned.
1.5765 +** ^If zVfsName is NULL then the default VFS is returned.
1.5766 +**
1.5767 +** ^New VFSes are registered with sqlite3_vfs_register().
1.5768 +** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
1.5769 +** ^The same VFS can be registered multiple times without injury.
1.5770 +** ^To make an existing VFS into the default VFS, register it again
1.5771 +** with the makeDflt flag set. If two different VFSes with the
1.5772 +** same name are registered, the behavior is undefined. If a
1.5773 +** VFS is registered with a name that is NULL or an empty string,
1.5774 +** then the behavior is undefined.
1.5775 +**
1.5776 +** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
1.5777 +** ^(If the default VFS is unregistered, another VFS is chosen as
1.5778 +** the default. The choice for the new VFS is arbitrary.)^
1.5779 +*/
1.5780 +SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
1.5781 +SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
1.5782 +SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
1.5783 +
1.5784 +/*
1.5785 +** CAPI3REF: Mutexes
1.5786 +**
1.5787 +** The SQLite core uses these routines for thread
1.5788 +** synchronization. Though they are intended for internal
1.5789 +** use by SQLite, code that links against SQLite is
1.5790 +** permitted to use any of these routines.
1.5791 +**
1.5792 +** The SQLite source code contains multiple implementations
1.5793 +** of these mutex routines. An appropriate implementation
1.5794 +** is selected automatically at compile-time. ^(The following
1.5795 +** implementations are available in the SQLite core:
1.5796 +**
1.5797 +** <ul>
1.5798 +** <li> SQLITE_MUTEX_PTHREADS
1.5799 +** <li> SQLITE_MUTEX_W32
1.5800 +** <li> SQLITE_MUTEX_NOOP
1.5801 +** </ul>)^
1.5802 +**
1.5803 +** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
1.5804 +** that does no real locking and is appropriate for use in
1.5805 +** a single-threaded application. ^The SQLITE_MUTEX_PTHREADS and
1.5806 +** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
1.5807 +** and Windows.
1.5808 +**
1.5809 +** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
1.5810 +** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
1.5811 +** implementation is included with the library. In this case the
1.5812 +** application must supply a custom mutex implementation using the
1.5813 +** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
1.5814 +** before calling sqlite3_initialize() or any other public sqlite3_
1.5815 +** function that calls sqlite3_initialize().)^
1.5816 +**
1.5817 +** ^The sqlite3_mutex_alloc() routine allocates a new
1.5818 +** mutex and returns a pointer to it. ^If it returns NULL
1.5819 +** that means that a mutex could not be allocated. ^SQLite
1.5820 +** will unwind its stack and return an error. ^(The argument
1.5821 +** to sqlite3_mutex_alloc() is one of these integer constants:
1.5822 +**
1.5823 +** <ul>
1.5824 +** <li> SQLITE_MUTEX_FAST
1.5825 +** <li> SQLITE_MUTEX_RECURSIVE
1.5826 +** <li> SQLITE_MUTEX_STATIC_MASTER
1.5827 +** <li> SQLITE_MUTEX_STATIC_MEM
1.5828 +** <li> SQLITE_MUTEX_STATIC_MEM2
1.5829 +** <li> SQLITE_MUTEX_STATIC_PRNG
1.5830 +** <li> SQLITE_MUTEX_STATIC_LRU
1.5831 +** <li> SQLITE_MUTEX_STATIC_LRU2
1.5832 +** </ul>)^
1.5833 +**
1.5834 +** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
1.5835 +** cause sqlite3_mutex_alloc() to create
1.5836 +** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
1.5837 +** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
1.5838 +** The mutex implementation does not need to make a distinction
1.5839 +** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
1.5840 +** not want to. ^SQLite will only request a recursive mutex in
1.5841 +** cases where it really needs one. ^If a faster non-recursive mutex
1.5842 +** implementation is available on the host platform, the mutex subsystem
1.5843 +** might return such a mutex in response to SQLITE_MUTEX_FAST.
1.5844 +**
1.5845 +** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
1.5846 +** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
1.5847 +** a pointer to a static preexisting mutex. ^Six static mutexes are
1.5848 +** used by the current version of SQLite. Future versions of SQLite
1.5849 +** may add additional static mutexes. Static mutexes are for internal
1.5850 +** use by SQLite only. Applications that use SQLite mutexes should
1.5851 +** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
1.5852 +** SQLITE_MUTEX_RECURSIVE.
1.5853 +**
1.5854 +** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
1.5855 +** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
1.5856 +** returns a different mutex on every call. ^But for the static
1.5857 +** mutex types, the same mutex is returned on every call that has
1.5858 +** the same type number.
1.5859 +**
1.5860 +** ^The sqlite3_mutex_free() routine deallocates a previously
1.5861 +** allocated dynamic mutex. ^SQLite is careful to deallocate every
1.5862 +** dynamic mutex that it allocates. The dynamic mutexes must not be in
1.5863 +** use when they are deallocated. Attempting to deallocate a static
1.5864 +** mutex results in undefined behavior. ^SQLite never deallocates
1.5865 +** a static mutex.
1.5866 +**
1.5867 +** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
1.5868 +** to enter a mutex. ^If another thread is already within the mutex,
1.5869 +** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
1.5870 +** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
1.5871 +** upon successful entry. ^(Mutexes created using
1.5872 +** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
1.5873 +** In such cases the,
1.5874 +** mutex must be exited an equal number of times before another thread
1.5875 +** can enter.)^ ^(If the same thread tries to enter any other
1.5876 +** kind of mutex more than once, the behavior is undefined.
1.5877 +** SQLite will never exhibit
1.5878 +** such behavior in its own use of mutexes.)^
1.5879 +**
1.5880 +** ^(Some systems (for example, Windows 95) do not support the operation
1.5881 +** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
1.5882 +** will always return SQLITE_BUSY. The SQLite core only ever uses
1.5883 +** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
1.5884 +**
1.5885 +** ^The sqlite3_mutex_leave() routine exits a mutex that was
1.5886 +** previously entered by the same thread. ^(The behavior
1.5887 +** is undefined if the mutex is not currently entered by the
1.5888 +** calling thread or is not currently allocated. SQLite will
1.5889 +** never do either.)^
1.5890 +**
1.5891 +** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
1.5892 +** sqlite3_mutex_leave() is a NULL pointer, then all three routines
1.5893 +** behave as no-ops.
1.5894 +**
1.5895 +** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
1.5896 +*/
1.5897 +SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
1.5898 +SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
1.5899 +SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
1.5900 +SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
1.5901 +SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
1.5902 +
1.5903 +/*
1.5904 +** CAPI3REF: Mutex Methods Object
1.5905 +**
1.5906 +** An instance of this structure defines the low-level routines
1.5907 +** used to allocate and use mutexes.
1.5908 +**
1.5909 +** Usually, the default mutex implementations provided by SQLite are
1.5910 +** sufficient, however the user has the option of substituting a custom
1.5911 +** implementation for specialized deployments or systems for which SQLite
1.5912 +** does not provide a suitable implementation. In this case, the user
1.5913 +** creates and populates an instance of this structure to pass
1.5914 +** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
1.5915 +** Additionally, an instance of this structure can be used as an
1.5916 +** output variable when querying the system for the current mutex
1.5917 +** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
1.5918 +**
1.5919 +** ^The xMutexInit method defined by this structure is invoked as
1.5920 +** part of system initialization by the sqlite3_initialize() function.
1.5921 +** ^The xMutexInit routine is called by SQLite exactly once for each
1.5922 +** effective call to [sqlite3_initialize()].
1.5923 +**
1.5924 +** ^The xMutexEnd method defined by this structure is invoked as
1.5925 +** part of system shutdown by the sqlite3_shutdown() function. The
1.5926 +** implementation of this method is expected to release all outstanding
1.5927 +** resources obtained by the mutex methods implementation, especially
1.5928 +** those obtained by the xMutexInit method. ^The xMutexEnd()
1.5929 +** interface is invoked exactly once for each call to [sqlite3_shutdown()].
1.5930 +**
1.5931 +** ^(The remaining seven methods defined by this structure (xMutexAlloc,
1.5932 +** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
1.5933 +** xMutexNotheld) implement the following interfaces (respectively):
1.5934 +**
1.5935 +** <ul>
1.5936 +** <li> [sqlite3_mutex_alloc()] </li>
1.5937 +** <li> [sqlite3_mutex_free()] </li>
1.5938 +** <li> [sqlite3_mutex_enter()] </li>
1.5939 +** <li> [sqlite3_mutex_try()] </li>
1.5940 +** <li> [sqlite3_mutex_leave()] </li>
1.5941 +** <li> [sqlite3_mutex_held()] </li>
1.5942 +** <li> [sqlite3_mutex_notheld()] </li>
1.5943 +** </ul>)^
1.5944 +**
1.5945 +** The only difference is that the public sqlite3_XXX functions enumerated
1.5946 +** above silently ignore any invocations that pass a NULL pointer instead
1.5947 +** of a valid mutex handle. The implementations of the methods defined
1.5948 +** by this structure are not required to handle this case, the results
1.5949 +** of passing a NULL pointer instead of a valid mutex handle are undefined
1.5950 +** (i.e. it is acceptable to provide an implementation that segfaults if
1.5951 +** it is passed a NULL pointer).
1.5952 +**
1.5953 +** The xMutexInit() method must be threadsafe. ^It must be harmless to
1.5954 +** invoke xMutexInit() multiple times within the same process and without
1.5955 +** intervening calls to xMutexEnd(). Second and subsequent calls to
1.5956 +** xMutexInit() must be no-ops.
1.5957 +**
1.5958 +** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
1.5959 +** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
1.5960 +** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
1.5961 +** memory allocation for a fast or recursive mutex.
1.5962 +**
1.5963 +** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
1.5964 +** called, but only if the prior call to xMutexInit returned SQLITE_OK.
1.5965 +** If xMutexInit fails in any way, it is expected to clean up after itself
1.5966 +** prior to returning.
1.5967 +*/
1.5968 +typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
1.5969 +struct sqlite3_mutex_methods {
1.5970 + int (*xMutexInit)(void);
1.5971 + int (*xMutexEnd)(void);
1.5972 + sqlite3_mutex *(*xMutexAlloc)(int);
1.5973 + void (*xMutexFree)(sqlite3_mutex *);
1.5974 + void (*xMutexEnter)(sqlite3_mutex *);
1.5975 + int (*xMutexTry)(sqlite3_mutex *);
1.5976 + void (*xMutexLeave)(sqlite3_mutex *);
1.5977 + int (*xMutexHeld)(sqlite3_mutex *);
1.5978 + int (*xMutexNotheld)(sqlite3_mutex *);
1.5979 +};
1.5980 +
1.5981 +/*
1.5982 +** CAPI3REF: Mutex Verification Routines
1.5983 +**
1.5984 +** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
1.5985 +** are intended for use inside assert() statements. ^The SQLite core
1.5986 +** never uses these routines except inside an assert() and applications
1.5987 +** are advised to follow the lead of the core. ^The SQLite core only
1.5988 +** provides implementations for these routines when it is compiled
1.5989 +** with the SQLITE_DEBUG flag. ^External mutex implementations
1.5990 +** are only required to provide these routines if SQLITE_DEBUG is
1.5991 +** defined and if NDEBUG is not defined.
1.5992 +**
1.5993 +** ^These routines should return true if the mutex in their argument
1.5994 +** is held or not held, respectively, by the calling thread.
1.5995 +**
1.5996 +** ^The implementation is not required to provide versions of these
1.5997 +** routines that actually work. If the implementation does not provide working
1.5998 +** versions of these routines, it should at least provide stubs that always
1.5999 +** return true so that one does not get spurious assertion failures.
1.6000 +**
1.6001 +** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
1.6002 +** the routine should return 1. This seems counter-intuitive since
1.6003 +** clearly the mutex cannot be held if it does not exist. But
1.6004 +** the reason the mutex does not exist is because the build is not
1.6005 +** using mutexes. And we do not want the assert() containing the
1.6006 +** call to sqlite3_mutex_held() to fail, so a non-zero return is
1.6007 +** the appropriate thing to do. ^The sqlite3_mutex_notheld()
1.6008 +** interface should also return 1 when given a NULL pointer.
1.6009 +*/
1.6010 +#ifndef NDEBUG
1.6011 +SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
1.6012 +SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
1.6013 +#endif
1.6014 +
1.6015 +/*
1.6016 +** CAPI3REF: Mutex Types
1.6017 +**
1.6018 +** The [sqlite3_mutex_alloc()] interface takes a single argument
1.6019 +** which is one of these integer constants.
1.6020 +**
1.6021 +** The set of static mutexes may change from one SQLite release to the
1.6022 +** next. Applications that override the built-in mutex logic must be
1.6023 +** prepared to accommodate additional static mutexes.
1.6024 +*/
1.6025 +#define SQLITE_MUTEX_FAST 0
1.6026 +#define SQLITE_MUTEX_RECURSIVE 1
1.6027 +#define SQLITE_MUTEX_STATIC_MASTER 2
1.6028 +#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
1.6029 +#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
1.6030 +#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
1.6031 +#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
1.6032 +#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
1.6033 +#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
1.6034 +#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
1.6035 +
1.6036 +/*
1.6037 +** CAPI3REF: Retrieve the mutex for a database connection
1.6038 +**
1.6039 +** ^This interface returns a pointer the [sqlite3_mutex] object that
1.6040 +** serializes access to the [database connection] given in the argument
1.6041 +** when the [threading mode] is Serialized.
1.6042 +** ^If the [threading mode] is Single-thread or Multi-thread then this
1.6043 +** routine returns a NULL pointer.
1.6044 +*/
1.6045 +SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
1.6046 +
1.6047 +/*
1.6048 +** CAPI3REF: Low-Level Control Of Database Files
1.6049 +**
1.6050 +** ^The [sqlite3_file_control()] interface makes a direct call to the
1.6051 +** xFileControl method for the [sqlite3_io_methods] object associated
1.6052 +** with a particular database identified by the second argument. ^The
1.6053 +** name of the database is "main" for the main database or "temp" for the
1.6054 +** TEMP database, or the name that appears after the AS keyword for
1.6055 +** databases that are added using the [ATTACH] SQL command.
1.6056 +** ^A NULL pointer can be used in place of "main" to refer to the
1.6057 +** main database file.
1.6058 +** ^The third and fourth parameters to this routine
1.6059 +** are passed directly through to the second and third parameters of
1.6060 +** the xFileControl method. ^The return value of the xFileControl
1.6061 +** method becomes the return value of this routine.
1.6062 +**
1.6063 +** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
1.6064 +** a pointer to the underlying [sqlite3_file] object to be written into
1.6065 +** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER
1.6066 +** case is a short-circuit path which does not actually invoke the
1.6067 +** underlying sqlite3_io_methods.xFileControl method.
1.6068 +**
1.6069 +** ^If the second parameter (zDbName) does not match the name of any
1.6070 +** open database file, then SQLITE_ERROR is returned. ^This error
1.6071 +** code is not remembered and will not be recalled by [sqlite3_errcode()]
1.6072 +** or [sqlite3_errmsg()]. The underlying xFileControl method might
1.6073 +** also return SQLITE_ERROR. There is no way to distinguish between
1.6074 +** an incorrect zDbName and an SQLITE_ERROR return from the underlying
1.6075 +** xFileControl method.
1.6076 +**
1.6077 +** See also: [SQLITE_FCNTL_LOCKSTATE]
1.6078 +*/
1.6079 +SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
1.6080 +
1.6081 +/*
1.6082 +** CAPI3REF: Testing Interface
1.6083 +**
1.6084 +** ^The sqlite3_test_control() interface is used to read out internal
1.6085 +** state of SQLite and to inject faults into SQLite for testing
1.6086 +** purposes. ^The first parameter is an operation code that determines
1.6087 +** the number, meaning, and operation of all subsequent parameters.
1.6088 +**
1.6089 +** This interface is not for use by applications. It exists solely
1.6090 +** for verifying the correct operation of the SQLite library. Depending
1.6091 +** on how the SQLite library is compiled, this interface might not exist.
1.6092 +**
1.6093 +** The details of the operation codes, their meanings, the parameters
1.6094 +** they take, and what they do are all subject to change without notice.
1.6095 +** Unlike most of the SQLite API, this function is not guaranteed to
1.6096 +** operate consistently from one release to the next.
1.6097 +*/
1.6098 +SQLITE_API int sqlite3_test_control(int op, ...);
1.6099 +
1.6100 +/*
1.6101 +** CAPI3REF: Testing Interface Operation Codes
1.6102 +**
1.6103 +** These constants are the valid operation code parameters used
1.6104 +** as the first argument to [sqlite3_test_control()].
1.6105 +**
1.6106 +** These parameters and their meanings are subject to change
1.6107 +** without notice. These values are for testing purposes only.
1.6108 +** Applications should not use any of these parameters or the
1.6109 +** [sqlite3_test_control()] interface.
1.6110 +*/
1.6111 +#define SQLITE_TESTCTRL_FIRST 5
1.6112 +#define SQLITE_TESTCTRL_PRNG_SAVE 5
1.6113 +#define SQLITE_TESTCTRL_PRNG_RESTORE 6
1.6114 +#define SQLITE_TESTCTRL_PRNG_RESET 7
1.6115 +#define SQLITE_TESTCTRL_BITVEC_TEST 8
1.6116 +#define SQLITE_TESTCTRL_FAULT_INSTALL 9
1.6117 +#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
1.6118 +#define SQLITE_TESTCTRL_PENDING_BYTE 11
1.6119 +#define SQLITE_TESTCTRL_ASSERT 12
1.6120 +#define SQLITE_TESTCTRL_ALWAYS 13
1.6121 +#define SQLITE_TESTCTRL_RESERVE 14
1.6122 +#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
1.6123 +#define SQLITE_TESTCTRL_ISKEYWORD 16
1.6124 +#define SQLITE_TESTCTRL_SCRATCHMALLOC 17
1.6125 +#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
1.6126 +#define SQLITE_TESTCTRL_EXPLAIN_STMT 19
1.6127 +#define SQLITE_TESTCTRL_NEVER_CORRUPT 20
1.6128 +#define SQLITE_TESTCTRL_VDBE_COVERAGE 21
1.6129 +#define SQLITE_TESTCTRL_LAST 21
1.6130 +
1.6131 +/*
1.6132 +** CAPI3REF: SQLite Runtime Status
1.6133 +**
1.6134 +** ^This interface is used to retrieve runtime status information
1.6135 +** about the performance of SQLite, and optionally to reset various
1.6136 +** highwater marks. ^The first argument is an integer code for
1.6137 +** the specific parameter to measure. ^(Recognized integer codes
1.6138 +** are of the form [status parameters | SQLITE_STATUS_...].)^
1.6139 +** ^The current value of the parameter is returned into *pCurrent.
1.6140 +** ^The highest recorded value is returned in *pHighwater. ^If the
1.6141 +** resetFlag is true, then the highest record value is reset after
1.6142 +** *pHighwater is written. ^(Some parameters do not record the highest
1.6143 +** value. For those parameters
1.6144 +** nothing is written into *pHighwater and the resetFlag is ignored.)^
1.6145 +** ^(Other parameters record only the highwater mark and not the current
1.6146 +** value. For these latter parameters nothing is written into *pCurrent.)^
1.6147 +**
1.6148 +** ^The sqlite3_status() routine returns SQLITE_OK on success and a
1.6149 +** non-zero [error code] on failure.
1.6150 +**
1.6151 +** This routine is threadsafe but is not atomic. This routine can be
1.6152 +** called while other threads are running the same or different SQLite
1.6153 +** interfaces. However the values returned in *pCurrent and
1.6154 +** *pHighwater reflect the status of SQLite at different points in time
1.6155 +** and it is possible that another thread might change the parameter
1.6156 +** in between the times when *pCurrent and *pHighwater are written.
1.6157 +**
1.6158 +** See also: [sqlite3_db_status()]
1.6159 +*/
1.6160 +SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
1.6161 +
1.6162 +
1.6163 +/*
1.6164 +** CAPI3REF: Status Parameters
1.6165 +** KEYWORDS: {status parameters}
1.6166 +**
1.6167 +** These integer constants designate various run-time status parameters
1.6168 +** that can be returned by [sqlite3_status()].
1.6169 +**
1.6170 +** <dl>
1.6171 +** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
1.6172 +** <dd>This parameter is the current amount of memory checked out
1.6173 +** using [sqlite3_malloc()], either directly or indirectly. The
1.6174 +** figure includes calls made to [sqlite3_malloc()] by the application
1.6175 +** and internal memory usage by the SQLite library. Scratch memory
1.6176 +** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
1.6177 +** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
1.6178 +** this parameter. The amount returned is the sum of the allocation
1.6179 +** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
1.6180 +**
1.6181 +** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
1.6182 +** <dd>This parameter records the largest memory allocation request
1.6183 +** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
1.6184 +** internal equivalents). Only the value returned in the
1.6185 +** *pHighwater parameter to [sqlite3_status()] is of interest.
1.6186 +** The value written into the *pCurrent parameter is undefined.</dd>)^
1.6187 +**
1.6188 +** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
1.6189 +** <dd>This parameter records the number of separate memory allocations
1.6190 +** currently checked out.</dd>)^
1.6191 +**
1.6192 +** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
1.6193 +** <dd>This parameter returns the number of pages used out of the
1.6194 +** [pagecache memory allocator] that was configured using
1.6195 +** [SQLITE_CONFIG_PAGECACHE]. The
1.6196 +** value returned is in pages, not in bytes.</dd>)^
1.6197 +**
1.6198 +** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
1.6199 +** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
1.6200 +** <dd>This parameter returns the number of bytes of page cache
1.6201 +** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
1.6202 +** buffer and where forced to overflow to [sqlite3_malloc()]. The
1.6203 +** returned value includes allocations that overflowed because they
1.6204 +** where too large (they were larger than the "sz" parameter to
1.6205 +** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
1.6206 +** no space was left in the page cache.</dd>)^
1.6207 +**
1.6208 +** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
1.6209 +** <dd>This parameter records the largest memory allocation request
1.6210 +** handed to [pagecache memory allocator]. Only the value returned in the
1.6211 +** *pHighwater parameter to [sqlite3_status()] is of interest.
1.6212 +** The value written into the *pCurrent parameter is undefined.</dd>)^
1.6213 +**
1.6214 +** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
1.6215 +** <dd>This parameter returns the number of allocations used out of the
1.6216 +** [scratch memory allocator] configured using
1.6217 +** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
1.6218 +** in bytes. Since a single thread may only have one scratch allocation
1.6219 +** outstanding at time, this parameter also reports the number of threads
1.6220 +** using scratch memory at the same time.</dd>)^
1.6221 +**
1.6222 +** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
1.6223 +** <dd>This parameter returns the number of bytes of scratch memory
1.6224 +** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
1.6225 +** buffer and where forced to overflow to [sqlite3_malloc()]. The values
1.6226 +** returned include overflows because the requested allocation was too
1.6227 +** larger (that is, because the requested allocation was larger than the
1.6228 +** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
1.6229 +** slots were available.
1.6230 +** </dd>)^
1.6231 +**
1.6232 +** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
1.6233 +** <dd>This parameter records the largest memory allocation request
1.6234 +** handed to [scratch memory allocator]. Only the value returned in the
1.6235 +** *pHighwater parameter to [sqlite3_status()] is of interest.
1.6236 +** The value written into the *pCurrent parameter is undefined.</dd>)^
1.6237 +**
1.6238 +** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
1.6239 +** <dd>This parameter records the deepest parser stack. It is only
1.6240 +** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
1.6241 +** </dl>
1.6242 +**
1.6243 +** New status parameters may be added from time to time.
1.6244 +*/
1.6245 +#define SQLITE_STATUS_MEMORY_USED 0
1.6246 +#define SQLITE_STATUS_PAGECACHE_USED 1
1.6247 +#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
1.6248 +#define SQLITE_STATUS_SCRATCH_USED 3
1.6249 +#define SQLITE_STATUS_SCRATCH_OVERFLOW 4
1.6250 +#define SQLITE_STATUS_MALLOC_SIZE 5
1.6251 +#define SQLITE_STATUS_PARSER_STACK 6
1.6252 +#define SQLITE_STATUS_PAGECACHE_SIZE 7
1.6253 +#define SQLITE_STATUS_SCRATCH_SIZE 8
1.6254 +#define SQLITE_STATUS_MALLOC_COUNT 9
1.6255 +
1.6256 +/*
1.6257 +** CAPI3REF: Database Connection Status
1.6258 +**
1.6259 +** ^This interface is used to retrieve runtime status information
1.6260 +** about a single [database connection]. ^The first argument is the
1.6261 +** database connection object to be interrogated. ^The second argument
1.6262 +** is an integer constant, taken from the set of
1.6263 +** [SQLITE_DBSTATUS options], that
1.6264 +** determines the parameter to interrogate. The set of
1.6265 +** [SQLITE_DBSTATUS options] is likely
1.6266 +** to grow in future releases of SQLite.
1.6267 +**
1.6268 +** ^The current value of the requested parameter is written into *pCur
1.6269 +** and the highest instantaneous value is written into *pHiwtr. ^If
1.6270 +** the resetFlg is true, then the highest instantaneous value is
1.6271 +** reset back down to the current value.
1.6272 +**
1.6273 +** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
1.6274 +** non-zero [error code] on failure.
1.6275 +**
1.6276 +** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
1.6277 +*/
1.6278 +SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
1.6279 +
1.6280 +/*
1.6281 +** CAPI3REF: Status Parameters for database connections
1.6282 +** KEYWORDS: {SQLITE_DBSTATUS options}
1.6283 +**
1.6284 +** These constants are the available integer "verbs" that can be passed as
1.6285 +** the second argument to the [sqlite3_db_status()] interface.
1.6286 +**
1.6287 +** New verbs may be added in future releases of SQLite. Existing verbs
1.6288 +** might be discontinued. Applications should check the return code from
1.6289 +** [sqlite3_db_status()] to make sure that the call worked.
1.6290 +** The [sqlite3_db_status()] interface will return a non-zero error code
1.6291 +** if a discontinued or unsupported verb is invoked.
1.6292 +**
1.6293 +** <dl>
1.6294 +** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
1.6295 +** <dd>This parameter returns the number of lookaside memory slots currently
1.6296 +** checked out.</dd>)^
1.6297 +**
1.6298 +** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
1.6299 +** <dd>This parameter returns the number malloc attempts that were
1.6300 +** satisfied using lookaside memory. Only the high-water value is meaningful;
1.6301 +** the current value is always zero.)^
1.6302 +**
1.6303 +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
1.6304 +** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
1.6305 +** <dd>This parameter returns the number malloc attempts that might have
1.6306 +** been satisfied using lookaside memory but failed due to the amount of
1.6307 +** memory requested being larger than the lookaside slot size.
1.6308 +** Only the high-water value is meaningful;
1.6309 +** the current value is always zero.)^
1.6310 +**
1.6311 +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
1.6312 +** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
1.6313 +** <dd>This parameter returns the number malloc attempts that might have
1.6314 +** been satisfied using lookaside memory but failed due to all lookaside
1.6315 +** memory already being in use.
1.6316 +** Only the high-water value is meaningful;
1.6317 +** the current value is always zero.)^
1.6318 +**
1.6319 +** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
1.6320 +** <dd>This parameter returns the approximate number of of bytes of heap
1.6321 +** memory used by all pager caches associated with the database connection.)^
1.6322 +** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
1.6323 +**
1.6324 +** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
1.6325 +** <dd>This parameter returns the approximate number of of bytes of heap
1.6326 +** memory used to store the schema for all databases associated
1.6327 +** with the connection - main, temp, and any [ATTACH]-ed databases.)^
1.6328 +** ^The full amount of memory used by the schemas is reported, even if the
1.6329 +** schema memory is shared with other database connections due to
1.6330 +** [shared cache mode] being enabled.
1.6331 +** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
1.6332 +**
1.6333 +** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
1.6334 +** <dd>This parameter returns the approximate number of of bytes of heap
1.6335 +** and lookaside memory used by all prepared statements associated with
1.6336 +** the database connection.)^
1.6337 +** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
1.6338 +** </dd>
1.6339 +**
1.6340 +** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
1.6341 +** <dd>This parameter returns the number of pager cache hits that have
1.6342 +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
1.6343 +** is always 0.
1.6344 +** </dd>
1.6345 +**
1.6346 +** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
1.6347 +** <dd>This parameter returns the number of pager cache misses that have
1.6348 +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
1.6349 +** is always 0.
1.6350 +** </dd>
1.6351 +**
1.6352 +** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
1.6353 +** <dd>This parameter returns the number of dirty cache entries that have
1.6354 +** been written to disk. Specifically, the number of pages written to the
1.6355 +** wal file in wal mode databases, or the number of pages written to the
1.6356 +** database file in rollback mode databases. Any pages written as part of
1.6357 +** transaction rollback or database recovery operations are not included.
1.6358 +** If an IO or other error occurs while writing a page to disk, the effect
1.6359 +** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
1.6360 +** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
1.6361 +** </dd>
1.6362 +**
1.6363 +** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
1.6364 +** <dd>This parameter returns zero for the current value if and only if
1.6365 +** all foreign key constraints (deferred or immediate) have been
1.6366 +** resolved.)^ ^The highwater mark is always 0.
1.6367 +** </dd>
1.6368 +** </dl>
1.6369 +*/
1.6370 +#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
1.6371 +#define SQLITE_DBSTATUS_CACHE_USED 1
1.6372 +#define SQLITE_DBSTATUS_SCHEMA_USED 2
1.6373 +#define SQLITE_DBSTATUS_STMT_USED 3
1.6374 +#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
1.6375 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
1.6376 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
1.6377 +#define SQLITE_DBSTATUS_CACHE_HIT 7
1.6378 +#define SQLITE_DBSTATUS_CACHE_MISS 8
1.6379 +#define SQLITE_DBSTATUS_CACHE_WRITE 9
1.6380 +#define SQLITE_DBSTATUS_DEFERRED_FKS 10
1.6381 +#define SQLITE_DBSTATUS_MAX 10 /* Largest defined DBSTATUS */
1.6382 +
1.6383 +
1.6384 +/*
1.6385 +** CAPI3REF: Prepared Statement Status
1.6386 +**
1.6387 +** ^(Each prepared statement maintains various
1.6388 +** [SQLITE_STMTSTATUS counters] that measure the number
1.6389 +** of times it has performed specific operations.)^ These counters can
1.6390 +** be used to monitor the performance characteristics of the prepared
1.6391 +** statements. For example, if the number of table steps greatly exceeds
1.6392 +** the number of table searches or result rows, that would tend to indicate
1.6393 +** that the prepared statement is using a full table scan rather than
1.6394 +** an index.
1.6395 +**
1.6396 +** ^(This interface is used to retrieve and reset counter values from
1.6397 +** a [prepared statement]. The first argument is the prepared statement
1.6398 +** object to be interrogated. The second argument
1.6399 +** is an integer code for a specific [SQLITE_STMTSTATUS counter]
1.6400 +** to be interrogated.)^
1.6401 +** ^The current value of the requested counter is returned.
1.6402 +** ^If the resetFlg is true, then the counter is reset to zero after this
1.6403 +** interface call returns.
1.6404 +**
1.6405 +** See also: [sqlite3_status()] and [sqlite3_db_status()].
1.6406 +*/
1.6407 +SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
1.6408 +
1.6409 +/*
1.6410 +** CAPI3REF: Status Parameters for prepared statements
1.6411 +** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
1.6412 +**
1.6413 +** These preprocessor macros define integer codes that name counter
1.6414 +** values associated with the [sqlite3_stmt_status()] interface.
1.6415 +** The meanings of the various counters are as follows:
1.6416 +**
1.6417 +** <dl>
1.6418 +** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
1.6419 +** <dd>^This is the number of times that SQLite has stepped forward in
1.6420 +** a table as part of a full table scan. Large numbers for this counter
1.6421 +** may indicate opportunities for performance improvement through
1.6422 +** careful use of indices.</dd>
1.6423 +**
1.6424 +** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
1.6425 +** <dd>^This is the number of sort operations that have occurred.
1.6426 +** A non-zero value in this counter may indicate an opportunity to
1.6427 +** improvement performance through careful use of indices.</dd>
1.6428 +**
1.6429 +** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
1.6430 +** <dd>^This is the number of rows inserted into transient indices that
1.6431 +** were created automatically in order to help joins run faster.
1.6432 +** A non-zero value in this counter may indicate an opportunity to
1.6433 +** improvement performance by adding permanent indices that do not
1.6434 +** need to be reinitialized each time the statement is run.</dd>
1.6435 +**
1.6436 +** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
1.6437 +** <dd>^This is the number of virtual machine operations executed
1.6438 +** by the prepared statement if that number is less than or equal
1.6439 +** to 2147483647. The number of virtual machine operations can be
1.6440 +** used as a proxy for the total work done by the prepared statement.
1.6441 +** If the number of virtual machine operations exceeds 2147483647
1.6442 +** then the value returned by this statement status code is undefined.
1.6443 +** </dd>
1.6444 +** </dl>
1.6445 +*/
1.6446 +#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
1.6447 +#define SQLITE_STMTSTATUS_SORT 2
1.6448 +#define SQLITE_STMTSTATUS_AUTOINDEX 3
1.6449 +#define SQLITE_STMTSTATUS_VM_STEP 4
1.6450 +
1.6451 +/*
1.6452 +** CAPI3REF: Custom Page Cache Object
1.6453 +**
1.6454 +** The sqlite3_pcache type is opaque. It is implemented by
1.6455 +** the pluggable module. The SQLite core has no knowledge of
1.6456 +** its size or internal structure and never deals with the
1.6457 +** sqlite3_pcache object except by holding and passing pointers
1.6458 +** to the object.
1.6459 +**
1.6460 +** See [sqlite3_pcache_methods2] for additional information.
1.6461 +*/
1.6462 +typedef struct sqlite3_pcache sqlite3_pcache;
1.6463 +
1.6464 +/*
1.6465 +** CAPI3REF: Custom Page Cache Object
1.6466 +**
1.6467 +** The sqlite3_pcache_page object represents a single page in the
1.6468 +** page cache. The page cache will allocate instances of this
1.6469 +** object. Various methods of the page cache use pointers to instances
1.6470 +** of this object as parameters or as their return value.
1.6471 +**
1.6472 +** See [sqlite3_pcache_methods2] for additional information.
1.6473 +*/
1.6474 +typedef struct sqlite3_pcache_page sqlite3_pcache_page;
1.6475 +struct sqlite3_pcache_page {
1.6476 + void *pBuf; /* The content of the page */
1.6477 + void *pExtra; /* Extra information associated with the page */
1.6478 +};
1.6479 +
1.6480 +/*
1.6481 +** CAPI3REF: Application Defined Page Cache.
1.6482 +** KEYWORDS: {page cache}
1.6483 +**
1.6484 +** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
1.6485 +** register an alternative page cache implementation by passing in an
1.6486 +** instance of the sqlite3_pcache_methods2 structure.)^
1.6487 +** In many applications, most of the heap memory allocated by
1.6488 +** SQLite is used for the page cache.
1.6489 +** By implementing a
1.6490 +** custom page cache using this API, an application can better control
1.6491 +** the amount of memory consumed by SQLite, the way in which
1.6492 +** that memory is allocated and released, and the policies used to
1.6493 +** determine exactly which parts of a database file are cached and for
1.6494 +** how long.
1.6495 +**
1.6496 +** The alternative page cache mechanism is an
1.6497 +** extreme measure that is only needed by the most demanding applications.
1.6498 +** The built-in page cache is recommended for most uses.
1.6499 +**
1.6500 +** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
1.6501 +** internal buffer by SQLite within the call to [sqlite3_config]. Hence
1.6502 +** the application may discard the parameter after the call to
1.6503 +** [sqlite3_config()] returns.)^
1.6504 +**
1.6505 +** [[the xInit() page cache method]]
1.6506 +** ^(The xInit() method is called once for each effective
1.6507 +** call to [sqlite3_initialize()])^
1.6508 +** (usually only once during the lifetime of the process). ^(The xInit()
1.6509 +** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
1.6510 +** The intent of the xInit() method is to set up global data structures
1.6511 +** required by the custom page cache implementation.
1.6512 +** ^(If the xInit() method is NULL, then the
1.6513 +** built-in default page cache is used instead of the application defined
1.6514 +** page cache.)^
1.6515 +**
1.6516 +** [[the xShutdown() page cache method]]
1.6517 +** ^The xShutdown() method is called by [sqlite3_shutdown()].
1.6518 +** It can be used to clean up
1.6519 +** any outstanding resources before process shutdown, if required.
1.6520 +** ^The xShutdown() method may be NULL.
1.6521 +**
1.6522 +** ^SQLite automatically serializes calls to the xInit method,
1.6523 +** so the xInit method need not be threadsafe. ^The
1.6524 +** xShutdown method is only called from [sqlite3_shutdown()] so it does
1.6525 +** not need to be threadsafe either. All other methods must be threadsafe
1.6526 +** in multithreaded applications.
1.6527 +**
1.6528 +** ^SQLite will never invoke xInit() more than once without an intervening
1.6529 +** call to xShutdown().
1.6530 +**
1.6531 +** [[the xCreate() page cache methods]]
1.6532 +** ^SQLite invokes the xCreate() method to construct a new cache instance.
1.6533 +** SQLite will typically create one cache instance for each open database file,
1.6534 +** though this is not guaranteed. ^The
1.6535 +** first parameter, szPage, is the size in bytes of the pages that must
1.6536 +** be allocated by the cache. ^szPage will always a power of two. ^The
1.6537 +** second parameter szExtra is a number of bytes of extra storage
1.6538 +** associated with each page cache entry. ^The szExtra parameter will
1.6539 +** a number less than 250. SQLite will use the
1.6540 +** extra szExtra bytes on each page to store metadata about the underlying
1.6541 +** database page on disk. The value passed into szExtra depends
1.6542 +** on the SQLite version, the target platform, and how SQLite was compiled.
1.6543 +** ^The third argument to xCreate(), bPurgeable, is true if the cache being
1.6544 +** created will be used to cache database pages of a file stored on disk, or
1.6545 +** false if it is used for an in-memory database. The cache implementation
1.6546 +** does not have to do anything special based with the value of bPurgeable;
1.6547 +** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
1.6548 +** never invoke xUnpin() except to deliberately delete a page.
1.6549 +** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
1.6550 +** false will always have the "discard" flag set to true.
1.6551 +** ^Hence, a cache created with bPurgeable false will
1.6552 +** never contain any unpinned pages.
1.6553 +**
1.6554 +** [[the xCachesize() page cache method]]
1.6555 +** ^(The xCachesize() method may be called at any time by SQLite to set the
1.6556 +** suggested maximum cache-size (number of pages stored by) the cache
1.6557 +** instance passed as the first argument. This is the value configured using
1.6558 +** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
1.6559 +** parameter, the implementation is not required to do anything with this
1.6560 +** value; it is advisory only.
1.6561 +**
1.6562 +** [[the xPagecount() page cache methods]]
1.6563 +** The xPagecount() method must return the number of pages currently
1.6564 +** stored in the cache, both pinned and unpinned.
1.6565 +**
1.6566 +** [[the xFetch() page cache methods]]
1.6567 +** The xFetch() method locates a page in the cache and returns a pointer to
1.6568 +** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
1.6569 +** The pBuf element of the returned sqlite3_pcache_page object will be a
1.6570 +** pointer to a buffer of szPage bytes used to store the content of a
1.6571 +** single database page. The pExtra element of sqlite3_pcache_page will be
1.6572 +** a pointer to the szExtra bytes of extra storage that SQLite has requested
1.6573 +** for each entry in the page cache.
1.6574 +**
1.6575 +** The page to be fetched is determined by the key. ^The minimum key value
1.6576 +** is 1. After it has been retrieved using xFetch, the page is considered
1.6577 +** to be "pinned".
1.6578 +**
1.6579 +** If the requested page is already in the page cache, then the page cache
1.6580 +** implementation must return a pointer to the page buffer with its content
1.6581 +** intact. If the requested page is not already in the cache, then the
1.6582 +** cache implementation should use the value of the createFlag
1.6583 +** parameter to help it determined what action to take:
1.6584 +**
1.6585 +** <table border=1 width=85% align=center>
1.6586 +** <tr><th> createFlag <th> Behavior when page is not already in cache
1.6587 +** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
1.6588 +** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
1.6589 +** Otherwise return NULL.
1.6590 +** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
1.6591 +** NULL if allocating a new page is effectively impossible.
1.6592 +** </table>
1.6593 +**
1.6594 +** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
1.6595 +** will only use a createFlag of 2 after a prior call with a createFlag of 1
1.6596 +** failed.)^ In between the to xFetch() calls, SQLite may
1.6597 +** attempt to unpin one or more cache pages by spilling the content of
1.6598 +** pinned pages to disk and synching the operating system disk cache.
1.6599 +**
1.6600 +** [[the xUnpin() page cache method]]
1.6601 +** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
1.6602 +** as its second argument. If the third parameter, discard, is non-zero,
1.6603 +** then the page must be evicted from the cache.
1.6604 +** ^If the discard parameter is
1.6605 +** zero, then the page may be discarded or retained at the discretion of
1.6606 +** page cache implementation. ^The page cache implementation
1.6607 +** may choose to evict unpinned pages at any time.
1.6608 +**
1.6609 +** The cache must not perform any reference counting. A single
1.6610 +** call to xUnpin() unpins the page regardless of the number of prior calls
1.6611 +** to xFetch().
1.6612 +**
1.6613 +** [[the xRekey() page cache methods]]
1.6614 +** The xRekey() method is used to change the key value associated with the
1.6615 +** page passed as the second argument. If the cache
1.6616 +** previously contains an entry associated with newKey, it must be
1.6617 +** discarded. ^Any prior cache entry associated with newKey is guaranteed not
1.6618 +** to be pinned.
1.6619 +**
1.6620 +** When SQLite calls the xTruncate() method, the cache must discard all
1.6621 +** existing cache entries with page numbers (keys) greater than or equal
1.6622 +** to the value of the iLimit parameter passed to xTruncate(). If any
1.6623 +** of these pages are pinned, they are implicitly unpinned, meaning that
1.6624 +** they can be safely discarded.
1.6625 +**
1.6626 +** [[the xDestroy() page cache method]]
1.6627 +** ^The xDestroy() method is used to delete a cache allocated by xCreate().
1.6628 +** All resources associated with the specified cache should be freed. ^After
1.6629 +** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
1.6630 +** handle invalid, and will not use it with any other sqlite3_pcache_methods2
1.6631 +** functions.
1.6632 +**
1.6633 +** [[the xShrink() page cache method]]
1.6634 +** ^SQLite invokes the xShrink() method when it wants the page cache to
1.6635 +** free up as much of heap memory as possible. The page cache implementation
1.6636 +** is not obligated to free any memory, but well-behaved implementations should
1.6637 +** do their best.
1.6638 +*/
1.6639 +typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
1.6640 +struct sqlite3_pcache_methods2 {
1.6641 + int iVersion;
1.6642 + void *pArg;
1.6643 + int (*xInit)(void*);
1.6644 + void (*xShutdown)(void*);
1.6645 + sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
1.6646 + void (*xCachesize)(sqlite3_pcache*, int nCachesize);
1.6647 + int (*xPagecount)(sqlite3_pcache*);
1.6648 + sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
1.6649 + void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
1.6650 + void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
1.6651 + unsigned oldKey, unsigned newKey);
1.6652 + void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
1.6653 + void (*xDestroy)(sqlite3_pcache*);
1.6654 + void (*xShrink)(sqlite3_pcache*);
1.6655 +};
1.6656 +
1.6657 +/*
1.6658 +** This is the obsolete pcache_methods object that has now been replaced
1.6659 +** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
1.6660 +** retained in the header file for backwards compatibility only.
1.6661 +*/
1.6662 +typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
1.6663 +struct sqlite3_pcache_methods {
1.6664 + void *pArg;
1.6665 + int (*xInit)(void*);
1.6666 + void (*xShutdown)(void*);
1.6667 + sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
1.6668 + void (*xCachesize)(sqlite3_pcache*, int nCachesize);
1.6669 + int (*xPagecount)(sqlite3_pcache*);
1.6670 + void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
1.6671 + void (*xUnpin)(sqlite3_pcache*, void*, int discard);
1.6672 + void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
1.6673 + void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
1.6674 + void (*xDestroy)(sqlite3_pcache*);
1.6675 +};
1.6676 +
1.6677 +
1.6678 +/*
1.6679 +** CAPI3REF: Online Backup Object
1.6680 +**
1.6681 +** The sqlite3_backup object records state information about an ongoing
1.6682 +** online backup operation. ^The sqlite3_backup object is created by
1.6683 +** a call to [sqlite3_backup_init()] and is destroyed by a call to
1.6684 +** [sqlite3_backup_finish()].
1.6685 +**
1.6686 +** See Also: [Using the SQLite Online Backup API]
1.6687 +*/
1.6688 +typedef struct sqlite3_backup sqlite3_backup;
1.6689 +
1.6690 +/*
1.6691 +** CAPI3REF: Online Backup API.
1.6692 +**
1.6693 +** The backup API copies the content of one database into another.
1.6694 +** It is useful either for creating backups of databases or
1.6695 +** for copying in-memory databases to or from persistent files.
1.6696 +**
1.6697 +** See Also: [Using the SQLite Online Backup API]
1.6698 +**
1.6699 +** ^SQLite holds a write transaction open on the destination database file
1.6700 +** for the duration of the backup operation.
1.6701 +** ^The source database is read-locked only while it is being read;
1.6702 +** it is not locked continuously for the entire backup operation.
1.6703 +** ^Thus, the backup may be performed on a live source database without
1.6704 +** preventing other database connections from
1.6705 +** reading or writing to the source database while the backup is underway.
1.6706 +**
1.6707 +** ^(To perform a backup operation:
1.6708 +** <ol>
1.6709 +** <li><b>sqlite3_backup_init()</b> is called once to initialize the
1.6710 +** backup,
1.6711 +** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
1.6712 +** the data between the two databases, and finally
1.6713 +** <li><b>sqlite3_backup_finish()</b> is called to release all resources
1.6714 +** associated with the backup operation.
1.6715 +** </ol>)^
1.6716 +** There should be exactly one call to sqlite3_backup_finish() for each
1.6717 +** successful call to sqlite3_backup_init().
1.6718 +**
1.6719 +** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
1.6720 +**
1.6721 +** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
1.6722 +** [database connection] associated with the destination database
1.6723 +** and the database name, respectively.
1.6724 +** ^The database name is "main" for the main database, "temp" for the
1.6725 +** temporary database, or the name specified after the AS keyword in
1.6726 +** an [ATTACH] statement for an attached database.
1.6727 +** ^The S and M arguments passed to
1.6728 +** sqlite3_backup_init(D,N,S,M) identify the [database connection]
1.6729 +** and database name of the source database, respectively.
1.6730 +** ^The source and destination [database connections] (parameters S and D)
1.6731 +** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
1.6732 +** an error.
1.6733 +**
1.6734 +** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
1.6735 +** returned and an error code and error message are stored in the
1.6736 +** destination [database connection] D.
1.6737 +** ^The error code and message for the failed call to sqlite3_backup_init()
1.6738 +** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
1.6739 +** [sqlite3_errmsg16()] functions.
1.6740 +** ^A successful call to sqlite3_backup_init() returns a pointer to an
1.6741 +** [sqlite3_backup] object.
1.6742 +** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
1.6743 +** sqlite3_backup_finish() functions to perform the specified backup
1.6744 +** operation.
1.6745 +**
1.6746 +** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
1.6747 +**
1.6748 +** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
1.6749 +** the source and destination databases specified by [sqlite3_backup] object B.
1.6750 +** ^If N is negative, all remaining source pages are copied.
1.6751 +** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
1.6752 +** are still more pages to be copied, then the function returns [SQLITE_OK].
1.6753 +** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
1.6754 +** from source to destination, then it returns [SQLITE_DONE].
1.6755 +** ^If an error occurs while running sqlite3_backup_step(B,N),
1.6756 +** then an [error code] is returned. ^As well as [SQLITE_OK] and
1.6757 +** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
1.6758 +** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
1.6759 +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
1.6760 +**
1.6761 +** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
1.6762 +** <ol>
1.6763 +** <li> the destination database was opened read-only, or
1.6764 +** <li> the destination database is using write-ahead-log journaling
1.6765 +** and the destination and source page sizes differ, or
1.6766 +** <li> the destination database is an in-memory database and the
1.6767 +** destination and source page sizes differ.
1.6768 +** </ol>)^
1.6769 +**
1.6770 +** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
1.6771 +** the [sqlite3_busy_handler | busy-handler function]
1.6772 +** is invoked (if one is specified). ^If the
1.6773 +** busy-handler returns non-zero before the lock is available, then
1.6774 +** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
1.6775 +** sqlite3_backup_step() can be retried later. ^If the source
1.6776 +** [database connection]
1.6777 +** is being used to write to the source database when sqlite3_backup_step()
1.6778 +** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
1.6779 +** case the call to sqlite3_backup_step() can be retried later on. ^(If
1.6780 +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
1.6781 +** [SQLITE_READONLY] is returned, then
1.6782 +** there is no point in retrying the call to sqlite3_backup_step(). These
1.6783 +** errors are considered fatal.)^ The application must accept
1.6784 +** that the backup operation has failed and pass the backup operation handle
1.6785 +** to the sqlite3_backup_finish() to release associated resources.
1.6786 +**
1.6787 +** ^The first call to sqlite3_backup_step() obtains an exclusive lock
1.6788 +** on the destination file. ^The exclusive lock is not released until either
1.6789 +** sqlite3_backup_finish() is called or the backup operation is complete
1.6790 +** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
1.6791 +** sqlite3_backup_step() obtains a [shared lock] on the source database that
1.6792 +** lasts for the duration of the sqlite3_backup_step() call.
1.6793 +** ^Because the source database is not locked between calls to
1.6794 +** sqlite3_backup_step(), the source database may be modified mid-way
1.6795 +** through the backup process. ^If the source database is modified by an
1.6796 +** external process or via a database connection other than the one being
1.6797 +** used by the backup operation, then the backup will be automatically
1.6798 +** restarted by the next call to sqlite3_backup_step(). ^If the source
1.6799 +** database is modified by the using the same database connection as is used
1.6800 +** by the backup operation, then the backup database is automatically
1.6801 +** updated at the same time.
1.6802 +**
1.6803 +** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
1.6804 +**
1.6805 +** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
1.6806 +** application wishes to abandon the backup operation, the application
1.6807 +** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
1.6808 +** ^The sqlite3_backup_finish() interfaces releases all
1.6809 +** resources associated with the [sqlite3_backup] object.
1.6810 +** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
1.6811 +** active write-transaction on the destination database is rolled back.
1.6812 +** The [sqlite3_backup] object is invalid
1.6813 +** and may not be used following a call to sqlite3_backup_finish().
1.6814 +**
1.6815 +** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
1.6816 +** sqlite3_backup_step() errors occurred, regardless or whether or not
1.6817 +** sqlite3_backup_step() completed.
1.6818 +** ^If an out-of-memory condition or IO error occurred during any prior
1.6819 +** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
1.6820 +** sqlite3_backup_finish() returns the corresponding [error code].
1.6821 +**
1.6822 +** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
1.6823 +** is not a permanent error and does not affect the return value of
1.6824 +** sqlite3_backup_finish().
1.6825 +**
1.6826 +** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]]
1.6827 +** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
1.6828 +**
1.6829 +** ^Each call to sqlite3_backup_step() sets two values inside
1.6830 +** the [sqlite3_backup] object: the number of pages still to be backed
1.6831 +** up and the total number of pages in the source database file.
1.6832 +** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
1.6833 +** retrieve these two values, respectively.
1.6834 +**
1.6835 +** ^The values returned by these functions are only updated by
1.6836 +** sqlite3_backup_step(). ^If the source database is modified during a backup
1.6837 +** operation, then the values are not updated to account for any extra
1.6838 +** pages that need to be updated or the size of the source database file
1.6839 +** changing.
1.6840 +**
1.6841 +** <b>Concurrent Usage of Database Handles</b>
1.6842 +**
1.6843 +** ^The source [database connection] may be used by the application for other
1.6844 +** purposes while a backup operation is underway or being initialized.
1.6845 +** ^If SQLite is compiled and configured to support threadsafe database
1.6846 +** connections, then the source database connection may be used concurrently
1.6847 +** from within other threads.
1.6848 +**
1.6849 +** However, the application must guarantee that the destination
1.6850 +** [database connection] is not passed to any other API (by any thread) after
1.6851 +** sqlite3_backup_init() is called and before the corresponding call to
1.6852 +** sqlite3_backup_finish(). SQLite does not currently check to see
1.6853 +** if the application incorrectly accesses the destination [database connection]
1.6854 +** and so no error code is reported, but the operations may malfunction
1.6855 +** nevertheless. Use of the destination database connection while a
1.6856 +** backup is in progress might also also cause a mutex deadlock.
1.6857 +**
1.6858 +** If running in [shared cache mode], the application must
1.6859 +** guarantee that the shared cache used by the destination database
1.6860 +** is not accessed while the backup is running. In practice this means
1.6861 +** that the application must guarantee that the disk file being
1.6862 +** backed up to is not accessed by any connection within the process,
1.6863 +** not just the specific connection that was passed to sqlite3_backup_init().
1.6864 +**
1.6865 +** The [sqlite3_backup] object itself is partially threadsafe. Multiple
1.6866 +** threads may safely make multiple concurrent calls to sqlite3_backup_step().
1.6867 +** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
1.6868 +** APIs are not strictly speaking threadsafe. If they are invoked at the
1.6869 +** same time as another thread is invoking sqlite3_backup_step() it is
1.6870 +** possible that they return invalid values.
1.6871 +*/
1.6872 +SQLITE_API sqlite3_backup *sqlite3_backup_init(
1.6873 + sqlite3 *pDest, /* Destination database handle */
1.6874 + const char *zDestName, /* Destination database name */
1.6875 + sqlite3 *pSource, /* Source database handle */
1.6876 + const char *zSourceName /* Source database name */
1.6877 +);
1.6878 +SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
1.6879 +SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
1.6880 +SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
1.6881 +SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
1.6882 +
1.6883 +/*
1.6884 +** CAPI3REF: Unlock Notification
1.6885 +**
1.6886 +** ^When running in shared-cache mode, a database operation may fail with
1.6887 +** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
1.6888 +** individual tables within the shared-cache cannot be obtained. See
1.6889 +** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
1.6890 +** ^This API may be used to register a callback that SQLite will invoke
1.6891 +** when the connection currently holding the required lock relinquishes it.
1.6892 +** ^This API is only available if the library was compiled with the
1.6893 +** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
1.6894 +**
1.6895 +** See Also: [Using the SQLite Unlock Notification Feature].
1.6896 +**
1.6897 +** ^Shared-cache locks are released when a database connection concludes
1.6898 +** its current transaction, either by committing it or rolling it back.
1.6899 +**
1.6900 +** ^When a connection (known as the blocked connection) fails to obtain a
1.6901 +** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
1.6902 +** identity of the database connection (the blocking connection) that
1.6903 +** has locked the required resource is stored internally. ^After an
1.6904 +** application receives an SQLITE_LOCKED error, it may call the
1.6905 +** sqlite3_unlock_notify() method with the blocked connection handle as
1.6906 +** the first argument to register for a callback that will be invoked
1.6907 +** when the blocking connections current transaction is concluded. ^The
1.6908 +** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
1.6909 +** call that concludes the blocking connections transaction.
1.6910 +**
1.6911 +** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
1.6912 +** there is a chance that the blocking connection will have already
1.6913 +** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
1.6914 +** If this happens, then the specified callback is invoked immediately,
1.6915 +** from within the call to sqlite3_unlock_notify().)^
1.6916 +**
1.6917 +** ^If the blocked connection is attempting to obtain a write-lock on a
1.6918 +** shared-cache table, and more than one other connection currently holds
1.6919 +** a read-lock on the same table, then SQLite arbitrarily selects one of
1.6920 +** the other connections to use as the blocking connection.
1.6921 +**
1.6922 +** ^(There may be at most one unlock-notify callback registered by a
1.6923 +** blocked connection. If sqlite3_unlock_notify() is called when the
1.6924 +** blocked connection already has a registered unlock-notify callback,
1.6925 +** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
1.6926 +** called with a NULL pointer as its second argument, then any existing
1.6927 +** unlock-notify callback is canceled. ^The blocked connections
1.6928 +** unlock-notify callback may also be canceled by closing the blocked
1.6929 +** connection using [sqlite3_close()].
1.6930 +**
1.6931 +** The unlock-notify callback is not reentrant. If an application invokes
1.6932 +** any sqlite3_xxx API functions from within an unlock-notify callback, a
1.6933 +** crash or deadlock may be the result.
1.6934 +**
1.6935 +** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
1.6936 +** returns SQLITE_OK.
1.6937 +**
1.6938 +** <b>Callback Invocation Details</b>
1.6939 +**
1.6940 +** When an unlock-notify callback is registered, the application provides a
1.6941 +** single void* pointer that is passed to the callback when it is invoked.
1.6942 +** However, the signature of the callback function allows SQLite to pass
1.6943 +** it an array of void* context pointers. The first argument passed to
1.6944 +** an unlock-notify callback is a pointer to an array of void* pointers,
1.6945 +** and the second is the number of entries in the array.
1.6946 +**
1.6947 +** When a blocking connections transaction is concluded, there may be
1.6948 +** more than one blocked connection that has registered for an unlock-notify
1.6949 +** callback. ^If two or more such blocked connections have specified the
1.6950 +** same callback function, then instead of invoking the callback function
1.6951 +** multiple times, it is invoked once with the set of void* context pointers
1.6952 +** specified by the blocked connections bundled together into an array.
1.6953 +** This gives the application an opportunity to prioritize any actions
1.6954 +** related to the set of unblocked database connections.
1.6955 +**
1.6956 +** <b>Deadlock Detection</b>
1.6957 +**
1.6958 +** Assuming that after registering for an unlock-notify callback a
1.6959 +** database waits for the callback to be issued before taking any further
1.6960 +** action (a reasonable assumption), then using this API may cause the
1.6961 +** application to deadlock. For example, if connection X is waiting for
1.6962 +** connection Y's transaction to be concluded, and similarly connection
1.6963 +** Y is waiting on connection X's transaction, then neither connection
1.6964 +** will proceed and the system may remain deadlocked indefinitely.
1.6965 +**
1.6966 +** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
1.6967 +** detection. ^If a given call to sqlite3_unlock_notify() would put the
1.6968 +** system in a deadlocked state, then SQLITE_LOCKED is returned and no
1.6969 +** unlock-notify callback is registered. The system is said to be in
1.6970 +** a deadlocked state if connection A has registered for an unlock-notify
1.6971 +** callback on the conclusion of connection B's transaction, and connection
1.6972 +** B has itself registered for an unlock-notify callback when connection
1.6973 +** A's transaction is concluded. ^Indirect deadlock is also detected, so
1.6974 +** the system is also considered to be deadlocked if connection B has
1.6975 +** registered for an unlock-notify callback on the conclusion of connection
1.6976 +** C's transaction, where connection C is waiting on connection A. ^Any
1.6977 +** number of levels of indirection are allowed.
1.6978 +**
1.6979 +** <b>The "DROP TABLE" Exception</b>
1.6980 +**
1.6981 +** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
1.6982 +** always appropriate to call sqlite3_unlock_notify(). There is however,
1.6983 +** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
1.6984 +** SQLite checks if there are any currently executing SELECT statements
1.6985 +** that belong to the same connection. If there are, SQLITE_LOCKED is
1.6986 +** returned. In this case there is no "blocking connection", so invoking
1.6987 +** sqlite3_unlock_notify() results in the unlock-notify callback being
1.6988 +** invoked immediately. If the application then re-attempts the "DROP TABLE"
1.6989 +** or "DROP INDEX" query, an infinite loop might be the result.
1.6990 +**
1.6991 +** One way around this problem is to check the extended error code returned
1.6992 +** by an sqlite3_step() call. ^(If there is a blocking connection, then the
1.6993 +** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
1.6994 +** the special "DROP TABLE/INDEX" case, the extended error code is just
1.6995 +** SQLITE_LOCKED.)^
1.6996 +*/
1.6997 +SQLITE_API int sqlite3_unlock_notify(
1.6998 + sqlite3 *pBlocked, /* Waiting connection */
1.6999 + void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
1.7000 + void *pNotifyArg /* Argument to pass to xNotify */
1.7001 +);
1.7002 +
1.7003 +
1.7004 +/*
1.7005 +** CAPI3REF: String Comparison
1.7006 +**
1.7007 +** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
1.7008 +** and extensions to compare the contents of two buffers containing UTF-8
1.7009 +** strings in a case-independent fashion, using the same definition of "case
1.7010 +** independence" that SQLite uses internally when comparing identifiers.
1.7011 +*/
1.7012 +SQLITE_API int sqlite3_stricmp(const char *, const char *);
1.7013 +SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
1.7014 +
1.7015 +/*
1.7016 +** CAPI3REF: String Globbing
1.7017 +*
1.7018 +** ^The [sqlite3_strglob(P,X)] interface returns zero if string X matches
1.7019 +** the glob pattern P, and it returns non-zero if string X does not match
1.7020 +** the glob pattern P. ^The definition of glob pattern matching used in
1.7021 +** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
1.7022 +** SQL dialect used by SQLite. ^The sqlite3_strglob(P,X) function is case
1.7023 +** sensitive.
1.7024 +**
1.7025 +** Note that this routine returns zero on a match and non-zero if the strings
1.7026 +** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
1.7027 +*/
1.7028 +SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
1.7029 +
1.7030 +/*
1.7031 +** CAPI3REF: Error Logging Interface
1.7032 +**
1.7033 +** ^The [sqlite3_log()] interface writes a message into the [error log]
1.7034 +** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
1.7035 +** ^If logging is enabled, the zFormat string and subsequent arguments are
1.7036 +** used with [sqlite3_snprintf()] to generate the final output string.
1.7037 +**
1.7038 +** The sqlite3_log() interface is intended for use by extensions such as
1.7039 +** virtual tables, collating functions, and SQL functions. While there is
1.7040 +** nothing to prevent an application from calling sqlite3_log(), doing so
1.7041 +** is considered bad form.
1.7042 +**
1.7043 +** The zFormat string must not be NULL.
1.7044 +**
1.7045 +** To avoid deadlocks and other threading problems, the sqlite3_log() routine
1.7046 +** will not use dynamically allocated memory. The log message is stored in
1.7047 +** a fixed-length buffer on the stack. If the log message is longer than
1.7048 +** a few hundred characters, it will be truncated to the length of the
1.7049 +** buffer.
1.7050 +*/
1.7051 +SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
1.7052 +
1.7053 +/*
1.7054 +** CAPI3REF: Write-Ahead Log Commit Hook
1.7055 +**
1.7056 +** ^The [sqlite3_wal_hook()] function is used to register a callback that
1.7057 +** will be invoked each time a database connection commits data to a
1.7058 +** [write-ahead log] (i.e. whenever a transaction is committed in
1.7059 +** [journal_mode | journal_mode=WAL mode]).
1.7060 +**
1.7061 +** ^The callback is invoked by SQLite after the commit has taken place and
1.7062 +** the associated write-lock on the database released, so the implementation
1.7063 +** may read, write or [checkpoint] the database as required.
1.7064 +**
1.7065 +** ^The first parameter passed to the callback function when it is invoked
1.7066 +** is a copy of the third parameter passed to sqlite3_wal_hook() when
1.7067 +** registering the callback. ^The second is a copy of the database handle.
1.7068 +** ^The third parameter is the name of the database that was written to -
1.7069 +** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
1.7070 +** is the number of pages currently in the write-ahead log file,
1.7071 +** including those that were just committed.
1.7072 +**
1.7073 +** The callback function should normally return [SQLITE_OK]. ^If an error
1.7074 +** code is returned, that error will propagate back up through the
1.7075 +** SQLite code base to cause the statement that provoked the callback
1.7076 +** to report an error, though the commit will have still occurred. If the
1.7077 +** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
1.7078 +** that does not correspond to any valid SQLite error code, the results
1.7079 +** are undefined.
1.7080 +**
1.7081 +** A single database handle may have at most a single write-ahead log callback
1.7082 +** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
1.7083 +** previously registered write-ahead log callback. ^Note that the
1.7084 +** [sqlite3_wal_autocheckpoint()] interface and the
1.7085 +** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
1.7086 +** those overwrite any prior [sqlite3_wal_hook()] settings.
1.7087 +*/
1.7088 +SQLITE_API void *sqlite3_wal_hook(
1.7089 + sqlite3*,
1.7090 + int(*)(void *,sqlite3*,const char*,int),
1.7091 + void*
1.7092 +);
1.7093 +
1.7094 +/*
1.7095 +** CAPI3REF: Configure an auto-checkpoint
1.7096 +**
1.7097 +** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
1.7098 +** [sqlite3_wal_hook()] that causes any database on [database connection] D
1.7099 +** to automatically [checkpoint]
1.7100 +** after committing a transaction if there are N or
1.7101 +** more frames in the [write-ahead log] file. ^Passing zero or
1.7102 +** a negative value as the nFrame parameter disables automatic
1.7103 +** checkpoints entirely.
1.7104 +**
1.7105 +** ^The callback registered by this function replaces any existing callback
1.7106 +** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
1.7107 +** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
1.7108 +** configured by this function.
1.7109 +**
1.7110 +** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
1.7111 +** from SQL.
1.7112 +**
1.7113 +** ^Every new [database connection] defaults to having the auto-checkpoint
1.7114 +** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
1.7115 +** pages. The use of this interface
1.7116 +** is only necessary if the default setting is found to be suboptimal
1.7117 +** for a particular application.
1.7118 +*/
1.7119 +SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
1.7120 +
1.7121 +/*
1.7122 +** CAPI3REF: Checkpoint a database
1.7123 +**
1.7124 +** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
1.7125 +** on [database connection] D to be [checkpointed]. ^If X is NULL or an
1.7126 +** empty string, then a checkpoint is run on all databases of
1.7127 +** connection D. ^If the database connection D is not in
1.7128 +** [WAL | write-ahead log mode] then this interface is a harmless no-op.
1.7129 +**
1.7130 +** ^The [wal_checkpoint pragma] can be used to invoke this interface
1.7131 +** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
1.7132 +** [wal_autocheckpoint pragma] can be used to cause this interface to be
1.7133 +** run whenever the WAL reaches a certain size threshold.
1.7134 +**
1.7135 +** See also: [sqlite3_wal_checkpoint_v2()]
1.7136 +*/
1.7137 +SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
1.7138 +
1.7139 +/*
1.7140 +** CAPI3REF: Checkpoint a database
1.7141 +**
1.7142 +** Run a checkpoint operation on WAL database zDb attached to database
1.7143 +** handle db. The specific operation is determined by the value of the
1.7144 +** eMode parameter:
1.7145 +**
1.7146 +** <dl>
1.7147 +** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
1.7148 +** Checkpoint as many frames as possible without waiting for any database
1.7149 +** readers or writers to finish. Sync the db file if all frames in the log
1.7150 +** are checkpointed. This mode is the same as calling
1.7151 +** sqlite3_wal_checkpoint(). The busy-handler callback is never invoked.
1.7152 +**
1.7153 +** <dt>SQLITE_CHECKPOINT_FULL<dd>
1.7154 +** This mode blocks (calls the busy-handler callback) until there is no
1.7155 +** database writer and all readers are reading from the most recent database
1.7156 +** snapshot. It then checkpoints all frames in the log file and syncs the
1.7157 +** database file. This call blocks database writers while it is running,
1.7158 +** but not database readers.
1.7159 +**
1.7160 +** <dt>SQLITE_CHECKPOINT_RESTART<dd>
1.7161 +** This mode works the same way as SQLITE_CHECKPOINT_FULL, except after
1.7162 +** checkpointing the log file it blocks (calls the busy-handler callback)
1.7163 +** until all readers are reading from the database file only. This ensures
1.7164 +** that the next client to write to the database file restarts the log file
1.7165 +** from the beginning. This call blocks database writers while it is running,
1.7166 +** but not database readers.
1.7167 +** </dl>
1.7168 +**
1.7169 +** If pnLog is not NULL, then *pnLog is set to the total number of frames in
1.7170 +** the log file before returning. If pnCkpt is not NULL, then *pnCkpt is set to
1.7171 +** the total number of checkpointed frames (including any that were already
1.7172 +** checkpointed when this function is called). *pnLog and *pnCkpt may be
1.7173 +** populated even if sqlite3_wal_checkpoint_v2() returns other than SQLITE_OK.
1.7174 +** If no values are available because of an error, they are both set to -1
1.7175 +** before returning to communicate this to the caller.
1.7176 +**
1.7177 +** All calls obtain an exclusive "checkpoint" lock on the database file. If
1.7178 +** any other process is running a checkpoint operation at the same time, the
1.7179 +** lock cannot be obtained and SQLITE_BUSY is returned. Even if there is a
1.7180 +** busy-handler configured, it will not be invoked in this case.
1.7181 +**
1.7182 +** The SQLITE_CHECKPOINT_FULL and RESTART modes also obtain the exclusive
1.7183 +** "writer" lock on the database file. If the writer lock cannot be obtained
1.7184 +** immediately, and a busy-handler is configured, it is invoked and the writer
1.7185 +** lock retried until either the busy-handler returns 0 or the lock is
1.7186 +** successfully obtained. The busy-handler is also invoked while waiting for
1.7187 +** database readers as described above. If the busy-handler returns 0 before
1.7188 +** the writer lock is obtained or while waiting for database readers, the
1.7189 +** checkpoint operation proceeds from that point in the same way as
1.7190 +** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
1.7191 +** without blocking any further. SQLITE_BUSY is returned in this case.
1.7192 +**
1.7193 +** If parameter zDb is NULL or points to a zero length string, then the
1.7194 +** specified operation is attempted on all WAL databases. In this case the
1.7195 +** values written to output parameters *pnLog and *pnCkpt are undefined. If
1.7196 +** an SQLITE_BUSY error is encountered when processing one or more of the
1.7197 +** attached WAL databases, the operation is still attempted on any remaining
1.7198 +** attached databases and SQLITE_BUSY is returned to the caller. If any other
1.7199 +** error occurs while processing an attached database, processing is abandoned
1.7200 +** and the error code returned to the caller immediately. If no error
1.7201 +** (SQLITE_BUSY or otherwise) is encountered while processing the attached
1.7202 +** databases, SQLITE_OK is returned.
1.7203 +**
1.7204 +** If database zDb is the name of an attached database that is not in WAL
1.7205 +** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. If
1.7206 +** zDb is not NULL (or a zero length string) and is not the name of any
1.7207 +** attached database, SQLITE_ERROR is returned to the caller.
1.7208 +*/
1.7209 +SQLITE_API int sqlite3_wal_checkpoint_v2(
1.7210 + sqlite3 *db, /* Database handle */
1.7211 + const char *zDb, /* Name of attached database (or NULL) */
1.7212 + int eMode, /* SQLITE_CHECKPOINT_* value */
1.7213 + int *pnLog, /* OUT: Size of WAL log in frames */
1.7214 + int *pnCkpt /* OUT: Total number of frames checkpointed */
1.7215 +);
1.7216 +
1.7217 +/*
1.7218 +** CAPI3REF: Checkpoint operation parameters
1.7219 +**
1.7220 +** These constants can be used as the 3rd parameter to
1.7221 +** [sqlite3_wal_checkpoint_v2()]. See the [sqlite3_wal_checkpoint_v2()]
1.7222 +** documentation for additional information about the meaning and use of
1.7223 +** each of these values.
1.7224 +*/
1.7225 +#define SQLITE_CHECKPOINT_PASSIVE 0
1.7226 +#define SQLITE_CHECKPOINT_FULL 1
1.7227 +#define SQLITE_CHECKPOINT_RESTART 2
1.7228 +
1.7229 +/*
1.7230 +** CAPI3REF: Virtual Table Interface Configuration
1.7231 +**
1.7232 +** This function may be called by either the [xConnect] or [xCreate] method
1.7233 +** of a [virtual table] implementation to configure
1.7234 +** various facets of the virtual table interface.
1.7235 +**
1.7236 +** If this interface is invoked outside the context of an xConnect or
1.7237 +** xCreate virtual table method then the behavior is undefined.
1.7238 +**
1.7239 +** At present, there is only one option that may be configured using
1.7240 +** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
1.7241 +** may be added in the future.
1.7242 +*/
1.7243 +SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
1.7244 +
1.7245 +/*
1.7246 +** CAPI3REF: Virtual Table Configuration Options
1.7247 +**
1.7248 +** These macros define the various options to the
1.7249 +** [sqlite3_vtab_config()] interface that [virtual table] implementations
1.7250 +** can use to customize and optimize their behavior.
1.7251 +**
1.7252 +** <dl>
1.7253 +** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
1.7254 +** <dd>Calls of the form
1.7255 +** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
1.7256 +** where X is an integer. If X is zero, then the [virtual table] whose
1.7257 +** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
1.7258 +** support constraints. In this configuration (which is the default) if
1.7259 +** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
1.7260 +** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
1.7261 +** specified as part of the users SQL statement, regardless of the actual
1.7262 +** ON CONFLICT mode specified.
1.7263 +**
1.7264 +** If X is non-zero, then the virtual table implementation guarantees
1.7265 +** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
1.7266 +** any modifications to internal or persistent data structures have been made.
1.7267 +** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
1.7268 +** is able to roll back a statement or database transaction, and abandon
1.7269 +** or continue processing the current SQL statement as appropriate.
1.7270 +** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
1.7271 +** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
1.7272 +** had been ABORT.
1.7273 +**
1.7274 +** Virtual table implementations that are required to handle OR REPLACE
1.7275 +** must do so within the [xUpdate] method. If a call to the
1.7276 +** [sqlite3_vtab_on_conflict()] function indicates that the current ON
1.7277 +** CONFLICT policy is REPLACE, the virtual table implementation should
1.7278 +** silently replace the appropriate rows within the xUpdate callback and
1.7279 +** return SQLITE_OK. Or, if this is not possible, it may return
1.7280 +** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
1.7281 +** constraint handling.
1.7282 +** </dl>
1.7283 +*/
1.7284 +#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
1.7285 +
1.7286 +/*
1.7287 +** CAPI3REF: Determine The Virtual Table Conflict Policy
1.7288 +**
1.7289 +** This function may only be called from within a call to the [xUpdate] method
1.7290 +** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
1.7291 +** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
1.7292 +** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
1.7293 +** of the SQL statement that triggered the call to the [xUpdate] method of the
1.7294 +** [virtual table].
1.7295 +*/
1.7296 +SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
1.7297 +
1.7298 +/*
1.7299 +** CAPI3REF: Conflict resolution modes
1.7300 +**
1.7301 +** These constants are returned by [sqlite3_vtab_on_conflict()] to
1.7302 +** inform a [virtual table] implementation what the [ON CONFLICT] mode
1.7303 +** is for the SQL statement being evaluated.
1.7304 +**
1.7305 +** Note that the [SQLITE_IGNORE] constant is also used as a potential
1.7306 +** return value from the [sqlite3_set_authorizer()] callback and that
1.7307 +** [SQLITE_ABORT] is also a [result code].
1.7308 +*/
1.7309 +#define SQLITE_ROLLBACK 1
1.7310 +/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
1.7311 +#define SQLITE_FAIL 3
1.7312 +/* #define SQLITE_ABORT 4 // Also an error code */
1.7313 +#define SQLITE_REPLACE 5
1.7314 +
1.7315 +
1.7316 +
1.7317 +/*
1.7318 +** Undo the hack that converts floating point types to integer for
1.7319 +** builds on processors without floating point support.
1.7320 +*/
1.7321 +#ifdef SQLITE_OMIT_FLOATING_POINT
1.7322 +# undef double
1.7323 +#endif
1.7324 +
1.7325 +#ifdef __cplusplus
1.7326 +} /* End of the 'extern "C"' block */
1.7327 +#endif
1.7328 +#endif /* _SQLITE3_H_ */
1.7329 +
1.7330 +/*
1.7331 +** 2010 August 30
1.7332 +**
1.7333 +** The author disclaims copyright to this source code. In place of
1.7334 +** a legal notice, here is a blessing:
1.7335 +**
1.7336 +** May you do good and not evil.
1.7337 +** May you find forgiveness for yourself and forgive others.
1.7338 +** May you share freely, never taking more than you give.
1.7339 +**
1.7340 +*************************************************************************
1.7341 +*/
1.7342 +
1.7343 +#ifndef _SQLITE3RTREE_H_
1.7344 +#define _SQLITE3RTREE_H_
1.7345 +
1.7346 +
1.7347 +#ifdef __cplusplus
1.7348 +extern "C" {
1.7349 +#endif
1.7350 +
1.7351 +typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
1.7352 +
1.7353 +/*
1.7354 +** Register a geometry callback named zGeom that can be used as part of an
1.7355 +** R-Tree geometry query as follows:
1.7356 +**
1.7357 +** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
1.7358 +*/
1.7359 +SQLITE_API int sqlite3_rtree_geometry_callback(
1.7360 + sqlite3 *db,
1.7361 + const char *zGeom,
1.7362 +#ifdef SQLITE_RTREE_INT_ONLY
1.7363 + int (*xGeom)(sqlite3_rtree_geometry*, int n, sqlite3_int64 *a, int *pRes),
1.7364 +#else
1.7365 + int (*xGeom)(sqlite3_rtree_geometry*, int n, double *a, int *pRes),
1.7366 +#endif
1.7367 + void *pContext
1.7368 +);
1.7369 +
1.7370 +
1.7371 +/*
1.7372 +** A pointer to a structure of the following type is passed as the first
1.7373 +** argument to callbacks registered using rtree_geometry_callback().
1.7374 +*/
1.7375 +struct sqlite3_rtree_geometry {
1.7376 + void *pContext; /* Copy of pContext passed to s_r_g_c() */
1.7377 + int nParam; /* Size of array aParam[] */
1.7378 + double *aParam; /* Parameters passed to SQL geom function */
1.7379 + void *pUser; /* Callback implementation user data */
1.7380 + void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
1.7381 +};
1.7382 +
1.7383 +
1.7384 +#ifdef __cplusplus
1.7385 +} /* end of the 'extern "C"' block */
1.7386 +#endif
1.7387 +
1.7388 +#endif /* ifndef _SQLITE3RTREE_H_ */
1.7389 +
