Annotation of elwix/files/sqlite/dist/sqlite3.h, revision 1.4.2.1
1.2 misho 1: /*
2: ** 2001 September 15
3: **
4: ** The author disclaims copyright to this source code. In place of
5: ** a legal notice, here is a blessing:
6: **
7: ** May you do good and not evil.
8: ** May you find forgiveness for yourself and forgive others.
9: ** May you share freely, never taking more than you give.
10: **
11: *************************************************************************
12: ** This header file defines the interface that the SQLite library
13: ** presents to client programs. If a C-function, structure, datatype,
14: ** or constant definition does not appear in this file, then it is
15: ** not a published API of SQLite, is subject to change without
16: ** notice, and should not be referenced by programs that use SQLite.
17: **
18: ** Some of the definitions that are in this file are marked as
19: ** "experimental". Experimental interfaces are normally new
20: ** features recently added to SQLite. We do not anticipate changes
21: ** to experimental interfaces but reserve the right to make minor changes
22: ** if experience from use "in the wild" suggest such changes are prudent.
23: **
24: ** The official C-language API documentation for SQLite is derived
25: ** from comments in this file. This file is the authoritative source
1.4 misho 26: ** on how SQLite interfaces are supposed to operate.
1.2 misho 27: **
28: ** The name of this file under configuration management is "sqlite.h.in".
29: ** The makefile makes some minor changes to this file (such as inserting
30: ** the version number) and changes its name to "sqlite3.h" as
31: ** part of the build process.
32: */
1.4 misho 33: #ifndef SQLITE3_H
34: #define SQLITE3_H
1.2 misho 35: #include <stdarg.h> /* Needed for the definition of va_list */
36:
37: /*
38: ** Make sure we can call this stuff from C++.
39: */
40: #ifdef __cplusplus
41: extern "C" {
42: #endif
43:
44:
45: /*
1.4 misho 46: ** Provide the ability to override linkage features of the interface.
1.2 misho 47: */
48: #ifndef SQLITE_EXTERN
49: # define SQLITE_EXTERN extern
50: #endif
51: #ifndef SQLITE_API
52: # define SQLITE_API
53: #endif
1.4 misho 54: #ifndef SQLITE_CDECL
55: # define SQLITE_CDECL
56: #endif
57: #ifndef SQLITE_APICALL
58: # define SQLITE_APICALL
59: #endif
60: #ifndef SQLITE_STDCALL
61: # define SQLITE_STDCALL SQLITE_APICALL
62: #endif
63: #ifndef SQLITE_CALLBACK
64: # define SQLITE_CALLBACK
65: #endif
66: #ifndef SQLITE_SYSAPI
67: # define SQLITE_SYSAPI
68: #endif
1.2 misho 69:
70: /*
71: ** These no-op macros are used in front of interfaces to mark those
72: ** interfaces as either deprecated or experimental. New applications
1.4 misho 73: ** should not use deprecated interfaces - they are supported for backwards
1.2 misho 74: ** compatibility only. Application writers should be aware that
75: ** experimental interfaces are subject to change in point releases.
76: **
77: ** These macros used to resolve to various kinds of compiler magic that
78: ** would generate warning messages when they were used. But that
79: ** compiler magic ended up generating such a flurry of bug reports
80: ** that we have taken it all out and gone back to using simple
81: ** noop macros.
82: */
83: #define SQLITE_DEPRECATED
84: #define SQLITE_EXPERIMENTAL
85:
86: /*
87: ** Ensure these symbols were not defined by some previous header file.
88: */
89: #ifdef SQLITE_VERSION
90: # undef SQLITE_VERSION
91: #endif
92: #ifdef SQLITE_VERSION_NUMBER
93: # undef SQLITE_VERSION_NUMBER
94: #endif
95:
96: /*
97: ** CAPI3REF: Compile-Time Library Version Numbers
98: **
99: ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
100: ** evaluates to a string literal that is the SQLite version in the
101: ** format "X.Y.Z" where X is the major version number (always 3 for
102: ** SQLite3) and Y is the minor version number and Z is the release number.)^
103: ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
104: ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
105: ** numbers used in [SQLITE_VERSION].)^
106: ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
107: ** be larger than the release from which it is derived. Either Y will
108: ** be held constant and Z will be incremented or else Y will be incremented
109: ** and Z will be reset to zero.
110: **
1.4.2.1 ! misho 111: ** Since [version 3.6.18] ([dateof:3.6.18]),
! 112: ** SQLite source code has been stored in the
1.2 misho 113: ** <a href="http://www.fossil-scm.org/">Fossil configuration management
114: ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
115: ** a string which identifies a particular check-in of SQLite
116: ** within its configuration management system. ^The SQLITE_SOURCE_ID
1.4.2.1 ! misho 117: ** string contains the date and time of the check-in (UTC) and a SHA1
! 118: ** or SHA3-256 hash of the entire source tree.
1.2 misho 119: **
120: ** See also: [sqlite3_libversion()],
121: ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
122: ** [sqlite_version()] and [sqlite_source_id()].
123: */
1.4.2.1 ! misho 124: #define SQLITE_VERSION "3.19.3"
! 125: #define SQLITE_VERSION_NUMBER 3019003
! 126: #define SQLITE_SOURCE_ID "2017-06-08 14:26:16 0ee482a1e0eae22e08edc8978c9733a96603d4509645f348ebf55b579e89636b"
1.2 misho 127:
128: /*
129: ** CAPI3REF: Run-Time Library Version Numbers
1.4.2.1 ! misho 130: ** KEYWORDS: sqlite3_version sqlite3_sourceid
1.2 misho 131: **
132: ** These interfaces provide the same information as the [SQLITE_VERSION],
133: ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
134: ** but are associated with the library instead of the header file. ^(Cautious
135: ** programmers might include assert() statements in their application to
136: ** verify that values returned by these interfaces match the macros in
1.4 misho 137: ** the header, and thus ensure that the application is
1.2 misho 138: ** compiled with matching library and header files.
139: **
140: ** <blockquote><pre>
141: ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
142: ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
143: ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
144: ** </pre></blockquote>)^
145: **
146: ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
147: ** macro. ^The sqlite3_libversion() function returns a pointer to the
148: ** to the sqlite3_version[] string constant. The sqlite3_libversion()
149: ** function is provided for use in DLLs since DLL users usually do not have
150: ** direct access to string constants within the DLL. ^The
151: ** sqlite3_libversion_number() function returns an integer equal to
152: ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
153: ** a pointer to a string constant whose value is the same as the
154: ** [SQLITE_SOURCE_ID] C preprocessor macro.
155: **
156: ** See also: [sqlite_version()] and [sqlite_source_id()].
157: */
158: SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
159: SQLITE_API const char *sqlite3_libversion(void);
160: SQLITE_API const char *sqlite3_sourceid(void);
161: SQLITE_API int sqlite3_libversion_number(void);
162:
163: /*
164: ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
165: **
166: ** ^The sqlite3_compileoption_used() function returns 0 or 1
167: ** indicating whether the specified option was defined at
168: ** compile time. ^The SQLITE_ prefix may be omitted from the
169: ** option name passed to sqlite3_compileoption_used().
170: **
171: ** ^The sqlite3_compileoption_get() function allows iterating
172: ** over the list of options that were defined at compile time by
173: ** returning the N-th compile time option string. ^If N is out of range,
174: ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
175: ** prefix is omitted from any strings returned by
176: ** sqlite3_compileoption_get().
177: **
178: ** ^Support for the diagnostic functions sqlite3_compileoption_used()
179: ** and sqlite3_compileoption_get() may be omitted by specifying the
180: ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
181: **
182: ** See also: SQL functions [sqlite_compileoption_used()] and
183: ** [sqlite_compileoption_get()] and the [compile_options pragma].
184: */
185: #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
186: SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
187: SQLITE_API const char *sqlite3_compileoption_get(int N);
188: #endif
189:
190: /*
191: ** CAPI3REF: Test To See If The Library Is Threadsafe
192: **
193: ** ^The sqlite3_threadsafe() function returns zero if and only if
194: ** SQLite was compiled with mutexing code omitted due to the
195: ** [SQLITE_THREADSAFE] compile-time option being set to 0.
196: **
197: ** SQLite can be compiled with or without mutexes. When
198: ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
199: ** are enabled and SQLite is threadsafe. When the
200: ** [SQLITE_THREADSAFE] macro is 0,
201: ** the mutexes are omitted. Without the mutexes, it is not safe
202: ** to use SQLite concurrently from more than one thread.
203: **
204: ** Enabling mutexes incurs a measurable performance penalty.
205: ** So if speed is of utmost importance, it makes sense to disable
206: ** the mutexes. But for maximum safety, mutexes should be enabled.
207: ** ^The default behavior is for mutexes to be enabled.
208: **
209: ** This interface can be used by an application to make sure that the
210: ** version of SQLite that it is linking against was compiled with
211: ** the desired setting of the [SQLITE_THREADSAFE] macro.
212: **
213: ** This interface only reports on the compile-time mutex setting
214: ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
215: ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
216: ** can be fully or partially disabled using a call to [sqlite3_config()]
217: ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
1.4 misho 218: ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the
1.2 misho 219: ** sqlite3_threadsafe() function shows only the compile-time setting of
220: ** thread safety, not any run-time changes to that setting made by
221: ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
222: ** is unchanged by calls to sqlite3_config().)^
223: **
224: ** See the [threading mode] documentation for additional information.
225: */
226: SQLITE_API int sqlite3_threadsafe(void);
227:
228: /*
229: ** CAPI3REF: Database Connection Handle
230: ** KEYWORDS: {database connection} {database connections}
231: **
232: ** Each open SQLite database is represented by a pointer to an instance of
233: ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
234: ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
235: ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
1.3 misho 236: ** and [sqlite3_close_v2()] are its destructors. There are many other
237: ** interfaces (such as
1.2 misho 238: ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
239: ** [sqlite3_busy_timeout()] to name but three) that are methods on an
240: ** sqlite3 object.
241: */
242: typedef struct sqlite3 sqlite3;
243:
244: /*
245: ** CAPI3REF: 64-Bit Integer Types
246: ** KEYWORDS: sqlite_int64 sqlite_uint64
247: **
248: ** Because there is no cross-platform way to specify 64-bit integer types
249: ** SQLite includes typedefs for 64-bit signed and unsigned integers.
250: **
251: ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
252: ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
253: ** compatibility only.
254: **
255: ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
256: ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
257: ** sqlite3_uint64 and sqlite_uint64 types can store integer values
258: ** between 0 and +18446744073709551615 inclusive.
259: */
260: #ifdef SQLITE_INT64_TYPE
261: typedef SQLITE_INT64_TYPE sqlite_int64;
1.4.2.1 ! misho 262: # ifdef SQLITE_UINT64_TYPE
! 263: typedef SQLITE_UINT64_TYPE sqlite_uint64;
! 264: # else
! 265: typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
! 266: # endif
1.2 misho 267: #elif defined(_MSC_VER) || defined(__BORLANDC__)
268: typedef __int64 sqlite_int64;
269: typedef unsigned __int64 sqlite_uint64;
270: #else
271: typedef long long int sqlite_int64;
272: typedef unsigned long long int sqlite_uint64;
273: #endif
274: typedef sqlite_int64 sqlite3_int64;
275: typedef sqlite_uint64 sqlite3_uint64;
276:
277: /*
278: ** If compiling for a processor that lacks floating point support,
279: ** substitute integer for floating-point.
280: */
281: #ifdef SQLITE_OMIT_FLOATING_POINT
282: # define double sqlite3_int64
283: #endif
284:
285: /*
286: ** CAPI3REF: Closing A Database Connection
1.4 misho 287: ** DESTRUCTOR: sqlite3
1.2 misho 288: **
1.3 misho 289: ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
290: ** for the [sqlite3] object.
1.4 misho 291: ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
1.3 misho 292: ** the [sqlite3] object is successfully destroyed and all associated
293: ** resources are deallocated.
294: **
295: ** ^If the database connection is associated with unfinalized prepared
296: ** statements or unfinished sqlite3_backup objects then sqlite3_close()
297: ** will leave the database connection open and return [SQLITE_BUSY].
298: ** ^If sqlite3_close_v2() is called with unfinalized prepared statements
1.4 misho 299: ** and/or unfinished sqlite3_backups, then the database connection becomes
1.3 misho 300: ** an unusable "zombie" which will automatically be deallocated when the
301: ** last prepared statement is finalized or the last sqlite3_backup is
302: ** finished. The sqlite3_close_v2() interface is intended for use with
303: ** host languages that are garbage collected, and where the order in which
304: ** destructors are called is arbitrary.
305: **
306: ** Applications should [sqlite3_finalize | finalize] all [prepared statements],
307: ** [sqlite3_blob_close | close] all [BLOB handles], and
308: ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
309: ** with the [sqlite3] object prior to attempting to close the object. ^If
1.4 misho 310: ** sqlite3_close_v2() is called on a [database connection] that still has
1.3 misho 311: ** outstanding [prepared statements], [BLOB handles], and/or
1.4 misho 312: ** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
1.3 misho 313: ** of resources is deferred until all [prepared statements], [BLOB handles],
314: ** and [sqlite3_backup] objects are also destroyed.
1.2 misho 315: **
1.3 misho 316: ** ^If an [sqlite3] object is destroyed while a transaction is open,
1.2 misho 317: ** the transaction is automatically rolled back.
318: **
1.3 misho 319: ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
320: ** must be either a NULL
1.2 misho 321: ** pointer or an [sqlite3] object pointer obtained
322: ** from [sqlite3_open()], [sqlite3_open16()], or
323: ** [sqlite3_open_v2()], and not previously closed.
1.3 misho 324: ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
325: ** argument is a harmless no-op.
1.2 misho 326: */
1.3 misho 327: SQLITE_API int sqlite3_close(sqlite3*);
328: SQLITE_API int sqlite3_close_v2(sqlite3*);
1.2 misho 329:
330: /*
331: ** The type for a callback function.
332: ** This is legacy and deprecated. It is included for historical
333: ** compatibility and is not documented.
334: */
335: typedef int (*sqlite3_callback)(void*,int,char**, char**);
336:
337: /*
338: ** CAPI3REF: One-Step Query Execution Interface
1.4 misho 339: ** METHOD: sqlite3
1.2 misho 340: **
341: ** The sqlite3_exec() interface is a convenience wrapper around
342: ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
343: ** that allows an application to run multiple statements of SQL
344: ** without having to use a lot of C code.
345: **
346: ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
347: ** semicolon-separate SQL statements passed into its 2nd argument,
348: ** in the context of the [database connection] passed in as its 1st
349: ** argument. ^If the callback function of the 3rd argument to
350: ** sqlite3_exec() is not NULL, then it is invoked for each result row
351: ** coming out of the evaluated SQL statements. ^The 4th argument to
352: ** sqlite3_exec() is relayed through to the 1st argument of each
353: ** callback invocation. ^If the callback pointer to sqlite3_exec()
354: ** is NULL, then no callback is ever invoked and result rows are
355: ** ignored.
356: **
357: ** ^If an error occurs while evaluating the SQL statements passed into
358: ** sqlite3_exec(), then execution of the current statement stops and
359: ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
360: ** is not NULL then any error message is written into memory obtained
361: ** from [sqlite3_malloc()] and passed back through the 5th parameter.
362: ** To avoid memory leaks, the application should invoke [sqlite3_free()]
363: ** on error message strings returned through the 5th parameter of
1.4 misho 364: ** sqlite3_exec() after the error message string is no longer needed.
1.2 misho 365: ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
366: ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
367: ** NULL before returning.
368: **
369: ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
370: ** routine returns SQLITE_ABORT without invoking the callback again and
371: ** without running any subsequent SQL statements.
372: **
373: ** ^The 2nd argument to the sqlite3_exec() callback function is the
374: ** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
375: ** callback is an array of pointers to strings obtained as if from
376: ** [sqlite3_column_text()], one for each column. ^If an element of a
377: ** result row is NULL then the corresponding string pointer for the
378: ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
379: ** sqlite3_exec() callback is an array of pointers to strings where each
380: ** entry represents the name of corresponding result column as obtained
381: ** from [sqlite3_column_name()].
382: **
383: ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
384: ** to an empty string, or a pointer that contains only whitespace and/or
385: ** SQL comments, then no SQL statements are evaluated and the database
386: ** is not changed.
387: **
388: ** Restrictions:
389: **
390: ** <ul>
1.4 misho 391: ** <li> The application must ensure that the 1st parameter to sqlite3_exec()
1.2 misho 392: ** is a valid and open [database connection].
1.4 misho 393: ** <li> The application must not close the [database connection] specified by
1.2 misho 394: ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
395: ** <li> The application must not modify the SQL statement text passed into
396: ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
397: ** </ul>
398: */
399: SQLITE_API int sqlite3_exec(
400: sqlite3*, /* An open database */
401: const char *sql, /* SQL to be evaluated */
402: int (*callback)(void*,int,char**,char**), /* Callback function */
403: void *, /* 1st argument to callback */
404: char **errmsg /* Error msg written here */
405: );
406:
407: /*
408: ** CAPI3REF: Result Codes
1.4 misho 409: ** KEYWORDS: {result code definitions}
1.2 misho 410: **
411: ** Many SQLite functions return an integer result code from the set shown
412: ** here in order to indicate success or failure.
413: **
414: ** New error codes may be added in future versions of SQLite.
415: **
1.4 misho 416: ** See also: [extended result code definitions]
1.2 misho 417: */
418: #define SQLITE_OK 0 /* Successful result */
419: /* beginning-of-error-codes */
420: #define SQLITE_ERROR 1 /* SQL error or missing database */
421: #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
422: #define SQLITE_PERM 3 /* Access permission denied */
423: #define SQLITE_ABORT 4 /* Callback routine requested an abort */
424: #define SQLITE_BUSY 5 /* The database file is locked */
425: #define SQLITE_LOCKED 6 /* A table in the database is locked */
426: #define SQLITE_NOMEM 7 /* A malloc() failed */
427: #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
428: #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
429: #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
430: #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
431: #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
432: #define SQLITE_FULL 13 /* Insertion failed because database is full */
433: #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
434: #define SQLITE_PROTOCOL 15 /* Database lock protocol error */
435: #define SQLITE_EMPTY 16 /* Database is empty */
436: #define SQLITE_SCHEMA 17 /* The database schema changed */
437: #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
438: #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
439: #define SQLITE_MISMATCH 20 /* Data type mismatch */
440: #define SQLITE_MISUSE 21 /* Library used incorrectly */
441: #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
442: #define SQLITE_AUTH 23 /* Authorization denied */
443: #define SQLITE_FORMAT 24 /* Auxiliary database format error */
444: #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
445: #define SQLITE_NOTADB 26 /* File opened that is not a database file */
1.4 misho 446: #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
447: #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
1.2 misho 448: #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
449: #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
450: /* end-of-error-codes */
451:
452: /*
453: ** CAPI3REF: Extended Result Codes
1.4 misho 454: ** KEYWORDS: {extended result code definitions}
1.2 misho 455: **
1.4 misho 456: ** In its default configuration, SQLite API routines return one of 30 integer
457: ** [result codes]. However, experience has shown that many of
1.2 misho 458: ** these result codes are too coarse-grained. They do not provide as
459: ** much information about problems as programmers might like. In an effort to
1.4.2.1 ! misho 460: ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
! 461: ** and later) include
1.2 misho 462: ** support for additional result codes that provide more detailed information
1.4 misho 463: ** about errors. These [extended result codes] are enabled or disabled
1.2 misho 464: ** on a per database connection basis using the
1.4 misho 465: ** [sqlite3_extended_result_codes()] API. Or, the extended code for
466: ** the most recent error can be obtained using
467: ** [sqlite3_extended_errcode()].
1.2 misho 468: */
469: #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
470: #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
471: #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
472: #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
473: #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
474: #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
475: #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
476: #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
477: #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
478: #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
479: #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
480: #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
481: #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
482: #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
483: #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
484: #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
485: #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
486: #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
487: #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
488: #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
489: #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
490: #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
1.3 misho 491: #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
1.4 misho 492: #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
493: #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
494: #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
495: #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8))
496: #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8))
1.2 misho 497: #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
498: #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
1.4 misho 499: #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
1.2 misho 500: #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
1.3 misho 501: #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
502: #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
1.4 misho 503: #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
1.2 misho 504: #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
505: #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
506: #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
1.4 misho 507: #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
508: #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
1.3 misho 509: #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
1.4 misho 510: #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
511: #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
512: #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
513: #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
514: #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
515: #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
516: #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
517: #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
518: #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
519: #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
520: #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
521: #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
522: #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
523: #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8))
524: #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8))
1.2 misho 525:
526: /*
527: ** CAPI3REF: Flags For File Open Operations
528: **
529: ** These bit values are intended for use in the
530: ** 3rd parameter to the [sqlite3_open_v2()] interface and
531: ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
532: */
533: #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
534: #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
535: #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
536: #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
537: #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
538: #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
539: #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
1.3 misho 540: #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
1.2 misho 541: #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
542: #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
543: #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
544: #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
545: #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
546: #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
547: #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
548: #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
549: #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
550: #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
551: #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
552: #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
553:
554: /* Reserved: 0x00F00000 */
555:
556: /*
557: ** CAPI3REF: Device Characteristics
558: **
559: ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
1.3 misho 560: ** object returns an integer which is a vector of these
1.2 misho 561: ** bit values expressing I/O characteristics of the mass storage
562: ** device that holds the file that the [sqlite3_io_methods]
563: ** refers to.
564: **
565: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
566: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
567: ** mean that writes of blocks that are nnn bytes in size and
568: ** are aligned to an address which is an integer multiple of
569: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
570: ** that when data is appended to a file, the data is appended
571: ** first then the size of the file is extended, never the other
572: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
573: ** information is written to disk in the same order as calls
574: ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
575: ** after reboot following a crash or power loss, the only bytes in a
576: ** file that were written at the application level might have changed
577: ** and that adjacent bytes, even bytes within the same sector are
1.4 misho 578: ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
1.4.2.1 ! misho 579: ** flag indicates that a file cannot be deleted when open. The
1.4 misho 580: ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
581: ** read-only media and cannot be changed even by processes with
582: ** elevated privileges.
1.2 misho 583: */
584: #define SQLITE_IOCAP_ATOMIC 0x00000001
585: #define SQLITE_IOCAP_ATOMIC512 0x00000002
586: #define SQLITE_IOCAP_ATOMIC1K 0x00000004
587: #define SQLITE_IOCAP_ATOMIC2K 0x00000008
588: #define SQLITE_IOCAP_ATOMIC4K 0x00000010
589: #define SQLITE_IOCAP_ATOMIC8K 0x00000020
590: #define SQLITE_IOCAP_ATOMIC16K 0x00000040
591: #define SQLITE_IOCAP_ATOMIC32K 0x00000080
592: #define SQLITE_IOCAP_ATOMIC64K 0x00000100
593: #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
594: #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
595: #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
596: #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
1.4 misho 597: #define SQLITE_IOCAP_IMMUTABLE 0x00002000
1.2 misho 598:
599: /*
600: ** CAPI3REF: File Locking Levels
601: **
602: ** SQLite uses one of these integer values as the second
603: ** argument to calls it makes to the xLock() and xUnlock() methods
604: ** of an [sqlite3_io_methods] object.
605: */
606: #define SQLITE_LOCK_NONE 0
607: #define SQLITE_LOCK_SHARED 1
608: #define SQLITE_LOCK_RESERVED 2
609: #define SQLITE_LOCK_PENDING 3
610: #define SQLITE_LOCK_EXCLUSIVE 4
611:
612: /*
613: ** CAPI3REF: Synchronization Type Flags
614: **
615: ** When SQLite invokes the xSync() method of an
616: ** [sqlite3_io_methods] object it uses a combination of
617: ** these integer values as the second argument.
618: **
619: ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
620: ** sync operation only needs to flush data to mass storage. Inode
621: ** information need not be flushed. If the lower four bits of the flag
622: ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
623: ** If the lower four bits equal SQLITE_SYNC_FULL, that means
624: ** to use Mac OS X style fullsync instead of fsync().
625: **
626: ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
627: ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
628: ** settings. The [synchronous pragma] determines when calls to the
629: ** xSync VFS method occur and applies uniformly across all platforms.
630: ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
631: ** energetic or rigorous or forceful the sync operations are and
632: ** only make a difference on Mac OSX for the default SQLite code.
633: ** (Third-party VFS implementations might also make the distinction
634: ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
635: ** operating systems natively supported by SQLite, only Mac OSX
636: ** cares about the difference.)
637: */
638: #define SQLITE_SYNC_NORMAL 0x00002
639: #define SQLITE_SYNC_FULL 0x00003
640: #define SQLITE_SYNC_DATAONLY 0x00010
641:
642: /*
643: ** CAPI3REF: OS Interface Open File Handle
644: **
645: ** An [sqlite3_file] object represents an open file in the
646: ** [sqlite3_vfs | OS interface layer]. Individual OS interface
647: ** implementations will
648: ** want to subclass this object by appending additional fields
649: ** for their own use. The pMethods entry is a pointer to an
650: ** [sqlite3_io_methods] object that defines methods for performing
651: ** I/O operations on the open file.
652: */
653: typedef struct sqlite3_file sqlite3_file;
654: struct sqlite3_file {
655: const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
656: };
657:
658: /*
659: ** CAPI3REF: OS Interface File Virtual Methods Object
660: **
661: ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
662: ** [sqlite3_file] object (or, more commonly, a subclass of the
663: ** [sqlite3_file] object) with a pointer to an instance of this object.
664: ** This object defines the methods used to perform various operations
665: ** against the open file represented by the [sqlite3_file] object.
666: **
667: ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
668: ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
669: ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
670: ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
671: ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
672: ** to NULL.
673: **
674: ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
675: ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
676: ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
677: ** flag may be ORed in to indicate that only the data of the file
678: ** and not its inode needs to be synced.
679: **
680: ** The integer values to xLock() and xUnlock() are one of
681: ** <ul>
682: ** <li> [SQLITE_LOCK_NONE],
683: ** <li> [SQLITE_LOCK_SHARED],
684: ** <li> [SQLITE_LOCK_RESERVED],
685: ** <li> [SQLITE_LOCK_PENDING], or
686: ** <li> [SQLITE_LOCK_EXCLUSIVE].
687: ** </ul>
688: ** xLock() increases the lock. xUnlock() decreases the lock.
689: ** The xCheckReservedLock() method checks whether any database connection,
690: ** either in this process or in some other process, is holding a RESERVED,
691: ** PENDING, or EXCLUSIVE lock on the file. It returns true
692: ** if such a lock exists and false otherwise.
693: **
694: ** The xFileControl() method is a generic interface that allows custom
695: ** VFS implementations to directly control an open file using the
696: ** [sqlite3_file_control()] interface. The second "op" argument is an
697: ** integer opcode. The third argument is a generic pointer intended to
698: ** point to a structure that may contain arguments or space in which to
699: ** write return values. Potential uses for xFileControl() might be
700: ** functions to enable blocking locks with timeouts, to change the
701: ** locking strategy (for example to use dot-file locks), to inquire
702: ** about the status of a lock, or to break stale locks. The SQLite
703: ** core reserves all opcodes less than 100 for its own use.
1.4 misho 704: ** A [file control opcodes | list of opcodes] less than 100 is available.
1.2 misho 705: ** Applications that define a custom xFileControl method should use opcodes
706: ** greater than 100 to avoid conflicts. VFS implementations should
707: ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
708: ** recognize.
709: **
710: ** The xSectorSize() method returns the sector size of the
711: ** device that underlies the file. The sector size is the
712: ** minimum write that can be performed without disturbing
713: ** other bytes in the file. The xDeviceCharacteristics()
714: ** method returns a bit vector describing behaviors of the
715: ** underlying device:
716: **
717: ** <ul>
718: ** <li> [SQLITE_IOCAP_ATOMIC]
719: ** <li> [SQLITE_IOCAP_ATOMIC512]
720: ** <li> [SQLITE_IOCAP_ATOMIC1K]
721: ** <li> [SQLITE_IOCAP_ATOMIC2K]
722: ** <li> [SQLITE_IOCAP_ATOMIC4K]
723: ** <li> [SQLITE_IOCAP_ATOMIC8K]
724: ** <li> [SQLITE_IOCAP_ATOMIC16K]
725: ** <li> [SQLITE_IOCAP_ATOMIC32K]
726: ** <li> [SQLITE_IOCAP_ATOMIC64K]
727: ** <li> [SQLITE_IOCAP_SAFE_APPEND]
728: ** <li> [SQLITE_IOCAP_SEQUENTIAL]
1.4.2.1 ! misho 729: ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
! 730: ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
! 731: ** <li> [SQLITE_IOCAP_IMMUTABLE]
1.2 misho 732: ** </ul>
733: **
734: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
735: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
736: ** mean that writes of blocks that are nnn bytes in size and
737: ** are aligned to an address which is an integer multiple of
738: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
739: ** that when data is appended to a file, the data is appended
740: ** first then the size of the file is extended, never the other
741: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
742: ** information is written to disk in the same order as calls
743: ** to xWrite().
744: **
745: ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
746: ** in the unread portions of the buffer with zeros. A VFS that
747: ** fails to zero-fill short reads might seem to work. However,
748: ** failure to zero-fill short reads will eventually lead to
749: ** database corruption.
750: */
751: typedef struct sqlite3_io_methods sqlite3_io_methods;
752: struct sqlite3_io_methods {
753: int iVersion;
754: int (*xClose)(sqlite3_file*);
755: int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
756: int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
757: int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
758: int (*xSync)(sqlite3_file*, int flags);
759: int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
760: int (*xLock)(sqlite3_file*, int);
761: int (*xUnlock)(sqlite3_file*, int);
762: int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
763: int (*xFileControl)(sqlite3_file*, int op, void *pArg);
764: int (*xSectorSize)(sqlite3_file*);
765: int (*xDeviceCharacteristics)(sqlite3_file*);
766: /* Methods above are valid for version 1 */
767: int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
768: int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
769: void (*xShmBarrier)(sqlite3_file*);
770: int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
771: /* Methods above are valid for version 2 */
1.4 misho 772: int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
773: int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
774: /* Methods above are valid for version 3 */
1.2 misho 775: /* Additional methods may be added in future releases */
776: };
777:
778: /*
779: ** CAPI3REF: Standard File Control Opcodes
1.4 misho 780: ** KEYWORDS: {file control opcodes} {file control opcode}
1.2 misho 781: **
782: ** These integer constants are opcodes for the xFileControl method
783: ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
784: ** interface.
785: **
1.4 misho 786: ** <ul>
787: ** <li>[[SQLITE_FCNTL_LOCKSTATE]]
1.2 misho 788: ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
789: ** opcode causes the xFileControl method to write the current state of
790: ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
791: ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
792: ** into an integer that the pArg argument points to. This capability
1.4 misho 793: ** is used during testing and is only available when the SQLITE_TEST
794: ** compile-time option is used.
795: **
1.3 misho 796: ** <li>[[SQLITE_FCNTL_SIZE_HINT]]
1.2 misho 797: ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
798: ** layer a hint of how large the database file will grow to be during the
799: ** current transaction. This hint is not guaranteed to be accurate but it
800: ** is often close. The underlying VFS might choose to preallocate database
801: ** file space based on this hint in order to help writes to the database
802: ** file run faster.
803: **
1.3 misho 804: ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
1.2 misho 805: ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
806: ** extends and truncates the database file in chunks of a size specified
807: ** by the user. The fourth argument to [sqlite3_file_control()] should
808: ** point to an integer (type int) containing the new chunk-size to use
809: ** for the nominated database. Allocating database file space in large
810: ** chunks (say 1MB at a time), may reduce file-system fragmentation and
811: ** improve performance on some systems.
812: **
1.3 misho 813: ** <li>[[SQLITE_FCNTL_FILE_POINTER]]
1.2 misho 814: ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
815: ** to the [sqlite3_file] object associated with a particular database
1.4 misho 816: ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER].
817: **
818: ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
819: ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
820: ** to the [sqlite3_file] object associated with the journal file (either
821: ** the [rollback journal] or the [write-ahead log]) for a particular database
822: ** connection. See also [SQLITE_FCNTL_FILE_POINTER].
1.2 misho 823: **
1.3 misho 824: ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
1.4 misho 825: ** No longer in use.
826: **
827: ** <li>[[SQLITE_FCNTL_SYNC]]
828: ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
829: ** sent to the VFS immediately before the xSync method is invoked on a
830: ** database file descriptor. Or, if the xSync method is not invoked
831: ** because the user has configured SQLite with
832: ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
833: ** of the xSync method. In most cases, the pointer argument passed with
834: ** this file-control is NULL. However, if the database file is being synced
835: ** as part of a multi-database commit, the argument points to a nul-terminated
836: ** string containing the transactions master-journal file name. VFSes that
837: ** do not need this signal should silently ignore this opcode. Applications
838: ** should not call [sqlite3_file_control()] with this opcode as doing so may
839: ** disrupt the operation of the specialized VFSes that do require it.
840: **
841: ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
842: ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
843: ** and sent to the VFS after a transaction has been committed immediately
844: ** but before the database is unlocked. VFSes that do not need this signal
845: ** should silently ignore this opcode. Applications should not call
846: ** [sqlite3_file_control()] with this opcode as doing so may disrupt the
847: ** operation of the specialized VFSes that do require it.
1.2 misho 848: **
1.3 misho 849: ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
1.2 misho 850: ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
851: ** retry counts and intervals for certain disk I/O operations for the
852: ** windows [VFS] in order to provide robustness in the presence of
853: ** anti-virus programs. By default, the windows VFS will retry file read,
854: ** file write, and file delete operations up to 10 times, with a delay
855: ** of 25 milliseconds before the first retry and with the delay increasing
856: ** by an additional 25 milliseconds with each subsequent retry. This
857: ** opcode allows these two values (10 retries and 25 milliseconds of delay)
858: ** to be adjusted. The values are changed for all database connections
859: ** within the same process. The argument is a pointer to an array of two
1.4.2.1 ! misho 860: ** integers where the first integer is the new retry count and the second
1.2 misho 861: ** integer is the delay. If either integer is negative, then the setting
862: ** is not changed but instead the prior value of that setting is written
863: ** into the array entry, allowing the current retry settings to be
864: ** interrogated. The zDbName parameter is ignored.
865: **
1.3 misho 866: ** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
1.2 misho 867: ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
1.3 misho 868: ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
1.2 misho 869: ** write ahead log and shared memory files used for transaction control
870: ** are automatically deleted when the latest connection to the database
871: ** closes. Setting persistent WAL mode causes those files to persist after
872: ** close. Persisting the files is useful when other processes that do not
873: ** have write permission on the directory containing the database file want
874: ** to read the database file, as the WAL and shared memory files must exist
875: ** in order for the database to be readable. The fourth parameter to
876: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
877: ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
878: ** WAL mode. If the integer is -1, then it is overwritten with the current
879: ** WAL persistence setting.
880: **
1.3 misho 881: ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
1.2 misho 882: ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
883: ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
884: ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
885: ** xDeviceCharacteristics methods. The fourth parameter to
886: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
887: ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
888: ** mode. If the integer is -1, then it is overwritten with the current
889: ** zero-damage mode setting.
890: **
1.3 misho 891: ** <li>[[SQLITE_FCNTL_OVERWRITE]]
1.2 misho 892: ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
893: ** a write transaction to indicate that, unless it is rolled back for some
894: ** reason, the entire database file will be overwritten by the current
895: ** transaction. This is used by VACUUM operations.
896: **
1.3 misho 897: ** <li>[[SQLITE_FCNTL_VFSNAME]]
1.2 misho 898: ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
899: ** all [VFSes] in the VFS stack. The names are of all VFS shims and the
900: ** final bottom-level VFS are written into memory obtained from
901: ** [sqlite3_malloc()] and the result is stored in the char* variable
902: ** that the fourth parameter of [sqlite3_file_control()] points to.
903: ** The caller is responsible for freeing the memory when done. As with
904: ** all file-control actions, there is no guarantee that this will actually
905: ** do anything. Callers should initialize the char* variable to a NULL
906: ** pointer in case this file-control is not implemented. This file-control
907: ** is intended for diagnostic use only.
1.3 misho 908: **
1.4 misho 909: ** <li>[[SQLITE_FCNTL_VFS_POINTER]]
910: ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
911: ** [VFSes] currently in use. ^(The argument X in
912: ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
913: ** of type "[sqlite3_vfs] **". This opcodes will set *X
914: ** to a pointer to the top-level VFS.)^
915: ** ^When there are multiple VFS shims in the stack, this opcode finds the
916: ** upper-most shim only.
917: **
1.3 misho 918: ** <li>[[SQLITE_FCNTL_PRAGMA]]
919: ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
920: ** file control is sent to the open [sqlite3_file] object corresponding
921: ** to the database file to which the pragma statement refers. ^The argument
922: ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
923: ** pointers to strings (char**) in which the second element of the array
924: ** is the name of the pragma and the third element is the argument to the
925: ** pragma or NULL if the pragma has no argument. ^The handler for an
926: ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
927: ** of the char** argument point to a string obtained from [sqlite3_mprintf()]
928: ** or the equivalent and that string will become the result of the pragma or
929: ** the error message if the pragma fails. ^If the
930: ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
931: ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
932: ** file control returns [SQLITE_OK], then the parser assumes that the
933: ** VFS has handled the PRAGMA itself and the parser generates a no-op
1.4 misho 934: ** prepared statement if result string is NULL, or that returns a copy
935: ** of the result string if the string is non-NULL.
936: ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1.3 misho 937: ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
938: ** that the VFS encountered an error while handling the [PRAGMA] and the
939: ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
940: ** file control occurs at the beginning of pragma statement analysis and so
941: ** it is able to override built-in [PRAGMA] statements.
942: **
943: ** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1.4 misho 944: ** ^The [SQLITE_FCNTL_BUSYHANDLER]
945: ** file-control may be invoked by SQLite on the database file handle
1.3 misho 946: ** shortly after it is opened in order to provide a custom VFS with access
947: ** to the connections busy-handler callback. The argument is of type (void **)
948: ** - an array of two (void *) values. The first (void *) actually points
949: ** to a function of type (int (*)(void *)). In order to invoke the connections
950: ** busy-handler, this function should be invoked with the second (void *) in
951: ** the array as the only argument. If it returns non-zero, then the operation
952: ** should be retried. If it returns zero, the custom VFS should abandon the
953: ** current operation.
954: **
955: ** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1.4 misho 956: ** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
957: ** to have SQLite generate a
1.3 misho 958: ** temporary filename using the same algorithm that is followed to generate
959: ** temporary filenames for TEMP tables and other internal uses. The
960: ** argument should be a char** which will be filled with the filename
961: ** written into memory obtained from [sqlite3_malloc()]. The caller should
962: ** invoke [sqlite3_free()] on the result to avoid a memory leak.
963: **
1.4 misho 964: ** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
965: ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
966: ** maximum number of bytes that will be used for memory-mapped I/O.
967: ** The argument is a pointer to a value of type sqlite3_int64 that
968: ** is an advisory maximum number of bytes in the file to memory map. The
969: ** pointer is overwritten with the old value. The limit is not changed if
970: ** the value originally pointed to is negative, and so the current limit
971: ** can be queried by passing in a pointer to a negative number. This
972: ** file-control is used internally to implement [PRAGMA mmap_size].
973: **
974: ** <li>[[SQLITE_FCNTL_TRACE]]
975: ** The [SQLITE_FCNTL_TRACE] file control provides advisory information
976: ** to the VFS about what the higher layers of the SQLite stack are doing.
977: ** This file control is used by some VFS activity tracing [shims].
978: ** The argument is a zero-terminated string. Higher layers in the
979: ** SQLite stack may generate instances of this file control if
980: ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
981: **
982: ** <li>[[SQLITE_FCNTL_HAS_MOVED]]
983: ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
984: ** pointer to an integer and it writes a boolean into that integer depending
985: ** on whether or not the file has been renamed, moved, or deleted since it
986: ** was first opened.
987: **
1.4.2.1 ! misho 988: ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
! 989: ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
! 990: ** underlying native file handle associated with a file handle. This file
! 991: ** control interprets its argument as a pointer to a native file handle and
! 992: ** writes the resulting value there.
! 993: **
1.4 misho 994: ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
995: ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
996: ** opcode causes the xFileControl method to swap the file handle with the one
997: ** pointed to by the pArg argument. This capability is used during testing
998: ** and only needs to be supported when SQLITE_TEST is defined.
999: **
1000: ** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1001: ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1002: ** be advantageous to block on the next WAL lock if the lock is not immediately
1003: ** available. The WAL subsystem issues this signal during rare
1004: ** circumstances in order to fix a problem with priority inversion.
1005: ** Applications should <em>not</em> use this file-control.
1006: **
1007: ** <li>[[SQLITE_FCNTL_ZIPVFS]]
1008: ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1009: ** VFS should return SQLITE_NOTFOUND for this opcode.
1010: **
1011: ** <li>[[SQLITE_FCNTL_RBU]]
1012: ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1013: ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for
1014: ** this opcode.
1.3 misho 1015: ** </ul>
1.2 misho 1016: */
1017: #define SQLITE_FCNTL_LOCKSTATE 1
1.4 misho 1018: #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2
1019: #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3
1020: #define SQLITE_FCNTL_LAST_ERRNO 4
1.2 misho 1021: #define SQLITE_FCNTL_SIZE_HINT 5
1022: #define SQLITE_FCNTL_CHUNK_SIZE 6
1023: #define SQLITE_FCNTL_FILE_POINTER 7
1024: #define SQLITE_FCNTL_SYNC_OMITTED 8
1025: #define SQLITE_FCNTL_WIN32_AV_RETRY 9
1026: #define SQLITE_FCNTL_PERSIST_WAL 10
1027: #define SQLITE_FCNTL_OVERWRITE 11
1028: #define SQLITE_FCNTL_VFSNAME 12
1029: #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
1.3 misho 1030: #define SQLITE_FCNTL_PRAGMA 14
1031: #define SQLITE_FCNTL_BUSYHANDLER 15
1032: #define SQLITE_FCNTL_TEMPFILENAME 16
1.4 misho 1033: #define SQLITE_FCNTL_MMAP_SIZE 18
1034: #define SQLITE_FCNTL_TRACE 19
1035: #define SQLITE_FCNTL_HAS_MOVED 20
1036: #define SQLITE_FCNTL_SYNC 21
1037: #define SQLITE_FCNTL_COMMIT_PHASETWO 22
1038: #define SQLITE_FCNTL_WIN32_SET_HANDLE 23
1039: #define SQLITE_FCNTL_WAL_BLOCK 24
1040: #define SQLITE_FCNTL_ZIPVFS 25
1041: #define SQLITE_FCNTL_RBU 26
1042: #define SQLITE_FCNTL_VFS_POINTER 27
1043: #define SQLITE_FCNTL_JOURNAL_POINTER 28
1.4.2.1 ! misho 1044: #define SQLITE_FCNTL_WIN32_GET_HANDLE 29
! 1045: #define SQLITE_FCNTL_PDB 30
1.4 misho 1046:
1047: /* deprecated names */
1048: #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE
1049: #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE
1050: #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO
1051:
1.2 misho 1052:
1053: /*
1054: ** CAPI3REF: Mutex Handle
1055: **
1056: ** The mutex module within SQLite defines [sqlite3_mutex] to be an
1057: ** abstract type for a mutex object. The SQLite core never looks
1058: ** at the internal representation of an [sqlite3_mutex]. It only
1059: ** deals with pointers to the [sqlite3_mutex] object.
1060: **
1061: ** Mutexes are created using [sqlite3_mutex_alloc()].
1062: */
1063: typedef struct sqlite3_mutex sqlite3_mutex;
1064:
1065: /*
1.4 misho 1066: ** CAPI3REF: Loadable Extension Thunk
1067: **
1068: ** A pointer to the opaque sqlite3_api_routines structure is passed as
1069: ** the third parameter to entry points of [loadable extensions]. This
1070: ** structure must be typedefed in order to work around compiler warnings
1071: ** on some platforms.
1072: */
1073: typedef struct sqlite3_api_routines sqlite3_api_routines;
1074:
1075: /*
1.2 misho 1076: ** CAPI3REF: OS Interface Object
1077: **
1078: ** An instance of the sqlite3_vfs object defines the interface between
1079: ** the SQLite core and the underlying operating system. The "vfs"
1080: ** in the name of the object stands for "virtual file system". See
1081: ** the [VFS | VFS documentation] for further information.
1082: **
1083: ** The value of the iVersion field is initially 1 but may be larger in
1084: ** future versions of SQLite. Additional fields may be appended to this
1085: ** object when the iVersion value is increased. Note that the structure
1086: ** of the sqlite3_vfs object changes in the transaction between
1087: ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
1088: ** modified.
1089: **
1090: ** The szOsFile field is the size of the subclassed [sqlite3_file]
1091: ** structure used by this VFS. mxPathname is the maximum length of
1092: ** a pathname in this VFS.
1093: **
1094: ** Registered sqlite3_vfs objects are kept on a linked list formed by
1095: ** the pNext pointer. The [sqlite3_vfs_register()]
1096: ** and [sqlite3_vfs_unregister()] interfaces manage this list
1097: ** in a thread-safe way. The [sqlite3_vfs_find()] interface
1098: ** searches the list. Neither the application code nor the VFS
1099: ** implementation should use the pNext pointer.
1100: **
1101: ** The pNext field is the only field in the sqlite3_vfs
1102: ** structure that SQLite will ever modify. SQLite will only access
1103: ** or modify this field while holding a particular static mutex.
1104: ** The application should never modify anything within the sqlite3_vfs
1105: ** object once the object has been registered.
1106: **
1107: ** The zName field holds the name of the VFS module. The name must
1108: ** be unique across all VFS modules.
1109: **
1110: ** [[sqlite3_vfs.xOpen]]
1111: ** ^SQLite guarantees that the zFilename parameter to xOpen
1112: ** is either a NULL pointer or string obtained
1113: ** from xFullPathname() with an optional suffix added.
1114: ** ^If a suffix is added to the zFilename parameter, it will
1115: ** consist of a single "-" character followed by no more than
1116: ** 11 alphanumeric and/or "-" characters.
1117: ** ^SQLite further guarantees that
1118: ** the string will be valid and unchanged until xClose() is
1119: ** called. Because of the previous sentence,
1120: ** the [sqlite3_file] can safely store a pointer to the
1121: ** filename if it needs to remember the filename for some reason.
1122: ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1123: ** must invent its own temporary name for the file. ^Whenever the
1124: ** xFilename parameter is NULL it will also be the case that the
1125: ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1126: **
1127: ** The flags argument to xOpen() includes all bits set in
1128: ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
1129: ** or [sqlite3_open16()] is used, then flags includes at least
1130: ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1131: ** If xOpen() opens a file read-only then it sets *pOutFlags to
1132: ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
1133: **
1134: ** ^(SQLite will also add one of the following flags to the xOpen()
1135: ** call, depending on the object being opened:
1136: **
1137: ** <ul>
1138: ** <li> [SQLITE_OPEN_MAIN_DB]
1139: ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
1140: ** <li> [SQLITE_OPEN_TEMP_DB]
1141: ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
1142: ** <li> [SQLITE_OPEN_TRANSIENT_DB]
1143: ** <li> [SQLITE_OPEN_SUBJOURNAL]
1144: ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
1145: ** <li> [SQLITE_OPEN_WAL]
1146: ** </ul>)^
1147: **
1148: ** The file I/O implementation can use the object type flags to
1149: ** change the way it deals with files. For example, an application
1150: ** that does not care about crash recovery or rollback might make
1151: ** the open of a journal file a no-op. Writes to this journal would
1152: ** also be no-ops, and any attempt to read the journal would return
1153: ** SQLITE_IOERR. Or the implementation might recognize that a database
1154: ** file will be doing page-aligned sector reads and writes in a random
1155: ** order and set up its I/O subsystem accordingly.
1156: **
1157: ** SQLite might also add one of the following flags to the xOpen method:
1158: **
1159: ** <ul>
1160: ** <li> [SQLITE_OPEN_DELETEONCLOSE]
1161: ** <li> [SQLITE_OPEN_EXCLUSIVE]
1162: ** </ul>
1163: **
1164: ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1165: ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
1166: ** will be set for TEMP databases and their journals, transient
1167: ** databases, and subjournals.
1168: **
1169: ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1170: ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1171: ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1172: ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1173: ** SQLITE_OPEN_CREATE, is used to indicate that file should always
1174: ** be created, and that it is an error if it already exists.
1175: ** It is <i>not</i> used to indicate the file should be opened
1176: ** for exclusive access.
1177: **
1178: ** ^At least szOsFile bytes of memory are allocated by SQLite
1179: ** to hold the [sqlite3_file] structure passed as the third
1180: ** argument to xOpen. The xOpen method does not have to
1181: ** allocate the structure; it should just fill it in. Note that
1182: ** the xOpen method must set the sqlite3_file.pMethods to either
1183: ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
1184: ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
1185: ** element will be valid after xOpen returns regardless of the success
1186: ** or failure of the xOpen call.
1187: **
1188: ** [[sqlite3_vfs.xAccess]]
1189: ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1190: ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1191: ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1192: ** to test whether a file is at least readable. The file can be a
1193: ** directory.
1194: **
1195: ** ^SQLite will always allocate at least mxPathname+1 bytes for the
1196: ** output buffer xFullPathname. The exact size of the output buffer
1197: ** is also passed as a parameter to both methods. If the output buffer
1198: ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1199: ** handled as a fatal error by SQLite, vfs implementations should endeavor
1200: ** to prevent this by setting mxPathname to a sufficiently large value.
1201: **
1202: ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1203: ** interfaces are not strictly a part of the filesystem, but they are
1204: ** included in the VFS structure for completeness.
1205: ** The xRandomness() function attempts to return nBytes bytes
1206: ** of good-quality randomness into zOut. The return value is
1207: ** the actual number of bytes of randomness obtained.
1208: ** The xSleep() method causes the calling thread to sleep for at
1209: ** least the number of microseconds given. ^The xCurrentTime()
1210: ** method returns a Julian Day Number for the current date and time as
1211: ** a floating point value.
1212: ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1213: ** Day Number multiplied by 86400000 (the number of milliseconds in
1214: ** a 24-hour day).
1215: ** ^SQLite will use the xCurrentTimeInt64() method to get the current
1216: ** date and time if that method is available (if iVersion is 2 or
1217: ** greater and the function pointer is not NULL) and will fall back
1218: ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1219: **
1220: ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1221: ** are not used by the SQLite core. These optional interfaces are provided
1222: ** by some VFSes to facilitate testing of the VFS code. By overriding
1223: ** system calls with functions under its control, a test program can
1224: ** simulate faults and error conditions that would otherwise be difficult
1225: ** or impossible to induce. The set of system calls that can be overridden
1226: ** varies from one VFS to another, and from one version of the same VFS to the
1227: ** next. Applications that use these interfaces must be prepared for any
1228: ** or all of these interfaces to be NULL or for their behavior to change
1229: ** from one release to the next. Applications must not attempt to access
1230: ** any of these methods if the iVersion of the VFS is less than 3.
1231: */
1232: typedef struct sqlite3_vfs sqlite3_vfs;
1233: typedef void (*sqlite3_syscall_ptr)(void);
1234: struct sqlite3_vfs {
1235: int iVersion; /* Structure version number (currently 3) */
1236: int szOsFile; /* Size of subclassed sqlite3_file */
1237: int mxPathname; /* Maximum file pathname length */
1238: sqlite3_vfs *pNext; /* Next registered VFS */
1239: const char *zName; /* Name of this virtual file system */
1240: void *pAppData; /* Pointer to application-specific data */
1241: int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1242: int flags, int *pOutFlags);
1243: int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1244: int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1245: int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1246: void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1247: void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1248: void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1249: void (*xDlClose)(sqlite3_vfs*, void*);
1250: int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1251: int (*xSleep)(sqlite3_vfs*, int microseconds);
1252: int (*xCurrentTime)(sqlite3_vfs*, double*);
1253: int (*xGetLastError)(sqlite3_vfs*, int, char *);
1254: /*
1255: ** The methods above are in version 1 of the sqlite_vfs object
1256: ** definition. Those that follow are added in version 2 or later
1257: */
1258: int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1259: /*
1260: ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1261: ** Those below are for version 3 and greater.
1262: */
1263: int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1264: sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1265: const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1266: /*
1267: ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1.4 misho 1268: ** New fields may be appended in future versions. The iVersion
1.2 misho 1269: ** value will increment whenever this happens.
1270: */
1271: };
1272:
1273: /*
1274: ** CAPI3REF: Flags for the xAccess VFS method
1275: **
1276: ** These integer constants can be used as the third parameter to
1277: ** the xAccess method of an [sqlite3_vfs] object. They determine
1278: ** what kind of permissions the xAccess method is looking for.
1279: ** With SQLITE_ACCESS_EXISTS, the xAccess method
1280: ** simply checks whether the file exists.
1281: ** With SQLITE_ACCESS_READWRITE, the xAccess method
1282: ** checks whether the named directory is both readable and writable
1283: ** (in other words, if files can be added, removed, and renamed within
1284: ** the directory).
1285: ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1286: ** [temp_store_directory pragma], though this could change in a future
1287: ** release of SQLite.
1288: ** With SQLITE_ACCESS_READ, the xAccess method
1289: ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
1290: ** currently unused, though it might be used in a future release of
1291: ** SQLite.
1292: */
1293: #define SQLITE_ACCESS_EXISTS 0
1294: #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
1295: #define SQLITE_ACCESS_READ 2 /* Unused */
1296:
1297: /*
1298: ** CAPI3REF: Flags for the xShmLock VFS method
1299: **
1300: ** These integer constants define the various locking operations
1301: ** allowed by the xShmLock method of [sqlite3_io_methods]. The
1302: ** following are the only legal combinations of flags to the
1303: ** xShmLock method:
1304: **
1305: ** <ul>
1306: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1307: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1308: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1309: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1310: ** </ul>
1311: **
1312: ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1.4 misho 1313: ** was given on the corresponding lock.
1.2 misho 1314: **
1315: ** The xShmLock method can transition between unlocked and SHARED or
1316: ** between unlocked and EXCLUSIVE. It cannot transition between SHARED
1317: ** and EXCLUSIVE.
1318: */
1319: #define SQLITE_SHM_UNLOCK 1
1320: #define SQLITE_SHM_LOCK 2
1321: #define SQLITE_SHM_SHARED 4
1322: #define SQLITE_SHM_EXCLUSIVE 8
1323:
1324: /*
1325: ** CAPI3REF: Maximum xShmLock index
1326: **
1327: ** The xShmLock method on [sqlite3_io_methods] may use values
1328: ** between 0 and this upper bound as its "offset" argument.
1329: ** The SQLite core will never attempt to acquire or release a
1330: ** lock outside of this range
1331: */
1332: #define SQLITE_SHM_NLOCK 8
1333:
1334:
1335: /*
1336: ** CAPI3REF: Initialize The SQLite Library
1337: **
1338: ** ^The sqlite3_initialize() routine initializes the
1339: ** SQLite library. ^The sqlite3_shutdown() routine
1340: ** deallocates any resources that were allocated by sqlite3_initialize().
1341: ** These routines are designed to aid in process initialization and
1342: ** shutdown on embedded systems. Workstation applications using
1343: ** SQLite normally do not need to invoke either of these routines.
1344: **
1345: ** A call to sqlite3_initialize() is an "effective" call if it is
1346: ** the first time sqlite3_initialize() is invoked during the lifetime of
1347: ** the process, or if it is the first time sqlite3_initialize() is invoked
1348: ** following a call to sqlite3_shutdown(). ^(Only an effective call
1349: ** of sqlite3_initialize() does any initialization. All other calls
1350: ** are harmless no-ops.)^
1351: **
1352: ** A call to sqlite3_shutdown() is an "effective" call if it is the first
1353: ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
1354: ** an effective call to sqlite3_shutdown() does any deinitialization.
1355: ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1356: **
1357: ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1358: ** is not. The sqlite3_shutdown() interface must only be called from a
1359: ** single thread. All open [database connections] must be closed and all
1360: ** other SQLite resources must be deallocated prior to invoking
1361: ** sqlite3_shutdown().
1362: **
1363: ** Among other things, ^sqlite3_initialize() will invoke
1364: ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
1365: ** will invoke sqlite3_os_end().
1366: **
1367: ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1368: ** ^If for some reason, sqlite3_initialize() is unable to initialize
1369: ** the library (perhaps it is unable to allocate a needed resource such
1370: ** as a mutex) it returns an [error code] other than [SQLITE_OK].
1371: **
1372: ** ^The sqlite3_initialize() routine is called internally by many other
1373: ** SQLite interfaces so that an application usually does not need to
1374: ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
1375: ** calls sqlite3_initialize() so the SQLite library will be automatically
1376: ** initialized when [sqlite3_open()] is called if it has not be initialized
1377: ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1378: ** compile-time option, then the automatic calls to sqlite3_initialize()
1379: ** are omitted and the application must call sqlite3_initialize() directly
1380: ** prior to using any other SQLite interface. For maximum portability,
1381: ** it is recommended that applications always invoke sqlite3_initialize()
1382: ** directly prior to using any other SQLite interface. Future releases
1383: ** of SQLite may require this. In other words, the behavior exhibited
1384: ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1385: ** default behavior in some future release of SQLite.
1386: **
1387: ** The sqlite3_os_init() routine does operating-system specific
1388: ** initialization of the SQLite library. The sqlite3_os_end()
1389: ** routine undoes the effect of sqlite3_os_init(). Typical tasks
1390: ** performed by these routines include allocation or deallocation
1391: ** of static resources, initialization of global variables,
1392: ** setting up a default [sqlite3_vfs] module, or setting up
1393: ** a default configuration using [sqlite3_config()].
1394: **
1395: ** The application should never invoke either sqlite3_os_init()
1396: ** or sqlite3_os_end() directly. The application should only invoke
1397: ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
1398: ** interface is called automatically by sqlite3_initialize() and
1399: ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
1400: ** implementations for sqlite3_os_init() and sqlite3_os_end()
1401: ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1402: ** When [custom builds | built for other platforms]
1403: ** (using the [SQLITE_OS_OTHER=1] compile-time
1404: ** option) the application must supply a suitable implementation for
1405: ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1406: ** implementation of sqlite3_os_init() or sqlite3_os_end()
1407: ** must return [SQLITE_OK] on success and some other [error code] upon
1408: ** failure.
1409: */
1410: SQLITE_API int sqlite3_initialize(void);
1411: SQLITE_API int sqlite3_shutdown(void);
1412: SQLITE_API int sqlite3_os_init(void);
1413: SQLITE_API int sqlite3_os_end(void);
1414:
1415: /*
1416: ** CAPI3REF: Configuring The SQLite Library
1417: **
1418: ** The sqlite3_config() interface is used to make global configuration
1419: ** changes to SQLite in order to tune SQLite to the specific needs of
1420: ** the application. The default configuration is recommended for most
1421: ** applications and so this routine is usually not necessary. It is
1422: ** provided to support rare applications with unusual needs.
1423: **
1.4 misho 1424: ** <b>The sqlite3_config() interface is not threadsafe. The application
1425: ** must ensure that no other SQLite interfaces are invoked by other
1426: ** threads while sqlite3_config() is running.</b>
1427: **
1428: ** The sqlite3_config() interface
1.2 misho 1429: ** may only be invoked prior to library initialization using
1430: ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1431: ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1432: ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1433: ** Note, however, that ^sqlite3_config() can be called as part of the
1434: ** implementation of an application-defined [sqlite3_os_init()].
1435: **
1436: ** The first argument to sqlite3_config() is an integer
1437: ** [configuration option] that determines
1438: ** what property of SQLite is to be configured. Subsequent arguments
1439: ** vary depending on the [configuration option]
1440: ** in the first argument.
1441: **
1442: ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1443: ** ^If the option is unknown or SQLite is unable to set the option
1444: ** then this routine returns a non-zero [error code].
1445: */
1446: SQLITE_API int sqlite3_config(int, ...);
1447:
1448: /*
1449: ** CAPI3REF: Configure database connections
1.4 misho 1450: ** METHOD: sqlite3
1.2 misho 1451: **
1452: ** The sqlite3_db_config() interface is used to make configuration
1453: ** changes to a [database connection]. The interface is similar to
1454: ** [sqlite3_config()] except that the changes apply to a single
1455: ** [database connection] (specified in the first argument).
1456: **
1457: ** The second argument to sqlite3_db_config(D,V,...) is the
1458: ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1459: ** that indicates what aspect of the [database connection] is being configured.
1460: ** Subsequent arguments vary depending on the configuration verb.
1461: **
1462: ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1463: ** the call is considered successful.
1464: */
1465: SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1466:
1467: /*
1468: ** CAPI3REF: Memory Allocation Routines
1469: **
1470: ** An instance of this object defines the interface between SQLite
1471: ** and low-level memory allocation routines.
1472: **
1473: ** This object is used in only one place in the SQLite interface.
1474: ** A pointer to an instance of this object is the argument to
1475: ** [sqlite3_config()] when the configuration option is
1476: ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1477: ** By creating an instance of this object
1478: ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1479: ** during configuration, an application can specify an alternative
1480: ** memory allocation subsystem for SQLite to use for all of its
1481: ** dynamic memory needs.
1482: **
1483: ** Note that SQLite comes with several [built-in memory allocators]
1484: ** that are perfectly adequate for the overwhelming majority of applications
1485: ** and that this object is only useful to a tiny minority of applications
1486: ** with specialized memory allocation requirements. This object is
1487: ** also used during testing of SQLite in order to specify an alternative
1488: ** memory allocator that simulates memory out-of-memory conditions in
1489: ** order to verify that SQLite recovers gracefully from such
1490: ** conditions.
1491: **
1492: ** The xMalloc, xRealloc, and xFree methods must work like the
1493: ** malloc(), realloc() and free() functions from the standard C library.
1494: ** ^SQLite guarantees that the second argument to
1495: ** xRealloc is always a value returned by a prior call to xRoundup.
1496: **
1497: ** xSize should return the allocated size of a memory allocation
1498: ** previously obtained from xMalloc or xRealloc. The allocated size
1499: ** is always at least as big as the requested size but may be larger.
1500: **
1501: ** The xRoundup method returns what would be the allocated size of
1502: ** a memory allocation given a particular requested size. Most memory
1503: ** allocators round up memory allocations at least to the next multiple
1504: ** of 8. Some allocators round up to a larger multiple or to a power of 2.
1505: ** Every memory allocation request coming in through [sqlite3_malloc()]
1506: ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1507: ** that causes the corresponding memory allocation to fail.
1508: **
1.4 misho 1509: ** The xInit method initializes the memory allocator. For example,
1.2 misho 1510: ** it might allocate any require mutexes or initialize internal data
1511: ** structures. The xShutdown method is invoked (indirectly) by
1512: ** [sqlite3_shutdown()] and should deallocate any resources acquired
1513: ** by xInit. The pAppData pointer is used as the only parameter to
1514: ** xInit and xShutdown.
1515: **
1516: ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1517: ** the xInit method, so the xInit method need not be threadsafe. The
1518: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
1519: ** not need to be threadsafe either. For all other methods, SQLite
1520: ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1521: ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1522: ** it is by default) and so the methods are automatically serialized.
1523: ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1524: ** methods must be threadsafe or else make their own arrangements for
1525: ** serialization.
1526: **
1527: ** SQLite will never invoke xInit() more than once without an intervening
1528: ** call to xShutdown().
1529: */
1530: typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1531: struct sqlite3_mem_methods {
1532: void *(*xMalloc)(int); /* Memory allocation function */
1533: void (*xFree)(void*); /* Free a prior allocation */
1534: void *(*xRealloc)(void*,int); /* Resize an allocation */
1535: int (*xSize)(void*); /* Return the size of an allocation */
1536: int (*xRoundup)(int); /* Round up request size to allocation size */
1537: int (*xInit)(void*); /* Initialize the memory allocator */
1538: void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1539: void *pAppData; /* Argument to xInit() and xShutdown() */
1540: };
1541:
1542: /*
1543: ** CAPI3REF: Configuration Options
1544: ** KEYWORDS: {configuration option}
1545: **
1546: ** These constants are the available integer configuration options that
1547: ** can be passed as the first argument to the [sqlite3_config()] interface.
1548: **
1549: ** New configuration options may be added in future releases of SQLite.
1550: ** Existing configuration options might be discontinued. Applications
1551: ** should check the return code from [sqlite3_config()] to make sure that
1552: ** the call worked. The [sqlite3_config()] interface will return a
1553: ** non-zero [error code] if a discontinued or unsupported configuration option
1554: ** is invoked.
1555: **
1556: ** <dl>
1557: ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1558: ** <dd>There are no arguments to this option. ^This option sets the
1559: ** [threading mode] to Single-thread. In other words, it disables
1560: ** all mutexing and puts SQLite into a mode where it can only be used
1561: ** by a single thread. ^If SQLite is compiled with
1562: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1563: ** it is not possible to change the [threading mode] from its default
1564: ** value of Single-thread and so [sqlite3_config()] will return
1565: ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1566: ** configuration option.</dd>
1567: **
1568: ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1569: ** <dd>There are no arguments to this option. ^This option sets the
1570: ** [threading mode] to Multi-thread. In other words, it disables
1571: ** mutexing on [database connection] and [prepared statement] objects.
1572: ** The application is responsible for serializing access to
1573: ** [database connections] and [prepared statements]. But other mutexes
1574: ** are enabled so that SQLite will be safe to use in a multi-threaded
1575: ** environment as long as no two threads attempt to use the same
1576: ** [database connection] at the same time. ^If SQLite is compiled with
1577: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1578: ** it is not possible to set the Multi-thread [threading mode] and
1579: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1580: ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1581: **
1582: ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1583: ** <dd>There are no arguments to this option. ^This option sets the
1584: ** [threading mode] to Serialized. In other words, this option enables
1585: ** all mutexes including the recursive
1586: ** mutexes on [database connection] and [prepared statement] objects.
1587: ** In this mode (which is the default when SQLite is compiled with
1588: ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1589: ** to [database connections] and [prepared statements] so that the
1590: ** application is free to use the same [database connection] or the
1591: ** same [prepared statement] in different threads at the same time.
1592: ** ^If SQLite is compiled with
1593: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1594: ** it is not possible to set the Serialized [threading mode] and
1595: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1596: ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1597: **
1598: ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1.4 misho 1599: ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1600: ** a pointer to an instance of the [sqlite3_mem_methods] structure.
1601: ** The argument specifies
1.2 misho 1602: ** alternative low-level memory allocation routines to be used in place of
1603: ** the memory allocation routines built into SQLite.)^ ^SQLite makes
1604: ** its own private copy of the content of the [sqlite3_mem_methods] structure
1605: ** before the [sqlite3_config()] call returns.</dd>
1606: **
1607: ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1.4 misho 1608: ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1609: ** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1610: ** The [sqlite3_mem_methods]
1.2 misho 1611: ** structure is filled with the currently defined memory allocation routines.)^
1612: ** This option can be used to overload the default memory allocation
1613: ** routines with a wrapper that simulations memory allocation failure or
1614: ** tracks memory usage, for example. </dd>
1615: **
1616: ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1.4 misho 1617: ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1618: ** interpreted as a boolean, which enables or disables the collection of
1619: ** memory allocation statistics. ^(When memory allocation statistics are
1620: ** disabled, the following SQLite interfaces become non-operational:
1.2 misho 1621: ** <ul>
1622: ** <li> [sqlite3_memory_used()]
1623: ** <li> [sqlite3_memory_highwater()]
1624: ** <li> [sqlite3_soft_heap_limit64()]
1.4 misho 1625: ** <li> [sqlite3_status64()]
1.2 misho 1626: ** </ul>)^
1627: ** ^Memory allocation statistics are enabled by default unless SQLite is
1628: ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1629: ** allocation statistics are disabled by default.
1630: ** </dd>
1631: **
1632: ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1.4 misho 1633: ** <dd> ^The SQLITE_CONFIG_SCRATCH option specifies a static memory buffer
1634: ** that SQLite can use for scratch memory. ^(There are three arguments
1635: ** to SQLITE_CONFIG_SCRATCH: A pointer an 8-byte
1.2 misho 1636: ** aligned memory buffer from which the scratch allocations will be
1637: ** drawn, the size of each scratch allocation (sz),
1.4 misho 1638: ** and the maximum number of scratch allocations (N).)^
1.2 misho 1639: ** The first argument must be a pointer to an 8-byte aligned buffer
1640: ** of at least sz*N bytes of memory.
1.4 misho 1641: ** ^SQLite will not use more than one scratch buffers per thread.
1642: ** ^SQLite will never request a scratch buffer that is more than 6
1643: ** times the database page size.
1644: ** ^If SQLite needs needs additional
1.2 misho 1645: ** scratch memory beyond what is provided by this configuration option, then
1.4 misho 1646: ** [sqlite3_malloc()] will be used to obtain the memory needed.<p>
1647: ** ^When the application provides any amount of scratch memory using
1648: ** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large
1649: ** [sqlite3_malloc|heap allocations].
1650: ** This can help [Robson proof|prevent memory allocation failures] due to heap
1651: ** fragmentation in low-memory embedded systems.
1652: ** </dd>
1.2 misho 1653: **
1654: ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1.4 misho 1655: ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1656: ** that SQLite can use for the database page cache with the default page
1657: ** cache implementation.
1658: ** This configuration option is a no-op if an application-define page
1659: ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1660: ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1661: ** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1662: ** and the number of cache lines (N).
1.2 misho 1663: ** The sz argument should be the size of the largest database page
1.4 misho 1664: ** (a power of two between 512 and 65536) plus some extra bytes for each
1665: ** page header. ^The number of extra bytes needed by the page header
1666: ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1667: ** ^It is harmless, apart from the wasted memory,
1668: ** for the sz parameter to be larger than necessary. The pMem
1669: ** argument must be either a NULL pointer or a pointer to an 8-byte
1670: ** aligned block of memory of at least sz*N bytes, otherwise
1671: ** subsequent behavior is undefined.
1672: ** ^When pMem is not NULL, SQLite will strive to use the memory provided
1673: ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1674: ** a page cache line is larger than sz bytes or if all of the pMem buffer
1675: ** is exhausted.
1676: ** ^If pMem is NULL and N is non-zero, then each database connection
1677: ** does an initial bulk allocation for page cache memory
1678: ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1679: ** of -1024*N bytes if N is negative, . ^If additional
1680: ** page cache memory is needed beyond what is provided by the initial
1681: ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1682: ** additional cache line. </dd>
1.2 misho 1683: **
1684: ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1.4 misho 1685: ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1686: ** that SQLite will use for all of its dynamic memory allocation needs
1687: ** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and
1688: ** [SQLITE_CONFIG_PAGECACHE].
1689: ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1690: ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1691: ** [SQLITE_ERROR] if invoked otherwise.
1692: ** ^There are three arguments to SQLITE_CONFIG_HEAP:
1693: ** An 8-byte aligned pointer to the memory,
1.2 misho 1694: ** the number of bytes in the memory buffer, and the minimum allocation size.
1695: ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1696: ** to using its default memory allocator (the system malloc() implementation),
1697: ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
1.4 misho 1698: ** memory pointer is not NULL then the alternative memory
1.2 misho 1699: ** allocator is engaged to handle all of SQLites memory allocation needs.
1700: ** The first pointer (the memory pointer) must be aligned to an 8-byte
1701: ** boundary or subsequent behavior of SQLite will be undefined.
1702: ** The minimum allocation size is capped at 2**12. Reasonable values
1703: ** for the minimum allocation size are 2**5 through 2**8.</dd>
1704: **
1705: ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1.4 misho 1706: ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1707: ** pointer to an instance of the [sqlite3_mutex_methods] structure.
1708: ** The argument specifies alternative low-level mutex routines to be used
1709: ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of
1710: ** the content of the [sqlite3_mutex_methods] structure before the call to
1.2 misho 1711: ** [sqlite3_config()] returns. ^If SQLite is compiled with
1712: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1713: ** the entire mutexing subsystem is omitted from the build and hence calls to
1714: ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1715: ** return [SQLITE_ERROR].</dd>
1716: **
1717: ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1.4 misho 1718: ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1719: ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The
1.2 misho 1720: ** [sqlite3_mutex_methods]
1721: ** structure is filled with the currently defined mutex routines.)^
1722: ** This option can be used to overload the default mutex allocation
1723: ** routines with a wrapper used to track mutex usage for performance
1724: ** profiling or testing, for example. ^If SQLite is compiled with
1725: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1726: ** the entire mutexing subsystem is omitted from the build and hence calls to
1727: ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1728: ** return [SQLITE_ERROR].</dd>
1729: **
1730: ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1.4 misho 1731: ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1732: ** the default size of lookaside memory on each [database connection].
1733: ** The first argument is the
1.2 misho 1734: ** size of each lookaside buffer slot and the second is the number of
1.4 misho 1735: ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE
1736: ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1737: ** option to [sqlite3_db_config()] can be used to change the lookaside
1.2 misho 1738: ** configuration on individual connections.)^ </dd>
1739: **
1740: ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1.4 misho 1741: ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1742: ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies
1743: ** the interface to a custom page cache implementation.)^
1744: ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1.2 misho 1745: **
1746: ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1.4 misho 1747: ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
1748: ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of
1749: ** the current page cache implementation into that object.)^ </dd>
1.2 misho 1750: **
1751: ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1.4 misho 1752: ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1753: ** global [error log].
1754: ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1.2 misho 1755: ** function with a call signature of void(*)(void*,int,const char*),
1756: ** and a pointer to void. ^If the function pointer is not NULL, it is
1757: ** invoked by [sqlite3_log()] to process each logging event. ^If the
1758: ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1759: ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1760: ** passed through as the first parameter to the application-defined logger
1761: ** function whenever that function is invoked. ^The second parameter to
1762: ** the logger function is a copy of the first parameter to the corresponding
1763: ** [sqlite3_log()] call and is intended to be a [result code] or an
1764: ** [extended result code]. ^The third parameter passed to the logger is
1765: ** log message after formatting via [sqlite3_snprintf()].
1766: ** The SQLite logging interface is not reentrant; the logger function
1767: ** supplied by the application must not invoke any SQLite interface.
1768: ** In a multi-threaded application, the application-defined logger
1769: ** function must be threadsafe. </dd>
1770: **
1771: ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1.4 misho 1772: ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
1773: ** If non-zero, then URI handling is globally enabled. If the parameter is zero,
1774: ** then URI handling is globally disabled.)^ ^If URI handling is globally
1775: ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
1776: ** [sqlite3_open16()] or
1.2 misho 1777: ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1778: ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1.4 misho 1779: ** connection is opened. ^If it is globally disabled, filenames are
1.2 misho 1780: ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1.4 misho 1781: ** database connection is opened. ^(By default, URI handling is globally
1.2 misho 1782: ** disabled. The default value may be changed by compiling with the
1.4 misho 1783: ** [SQLITE_USE_URI] symbol defined.)^
1.2 misho 1784: **
1.3 misho 1785: ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1.4 misho 1786: ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
1787: ** argument which is interpreted as a boolean in order to enable or disable
1788: ** the use of covering indices for full table scans in the query optimizer.
1789: ** ^The default setting is determined
1.3 misho 1790: ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1791: ** if that compile-time option is omitted.
1792: ** The ability to disable the use of covering indices for full table scans
1793: ** is because some incorrectly coded legacy applications might malfunction
1.4 misho 1794: ** when the optimization is enabled. Providing the ability to
1.3 misho 1795: ** disable the optimization allows the older, buggy application code to work
1796: ** without change even with newer versions of SQLite.
1797: **
1.2 misho 1798: ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1.3 misho 1799: ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1.2 misho 1800: ** <dd> These options are obsolete and should not be used by new code.
1801: ** They are retained for backwards compatibility but are now no-ops.
1.4 misho 1802: ** </dd>
1.3 misho 1803: **
1804: ** [[SQLITE_CONFIG_SQLLOG]]
1805: ** <dt>SQLITE_CONFIG_SQLLOG
1806: ** <dd>This option is only available if sqlite is compiled with the
1.4 misho 1807: ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1.3 misho 1808: ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1809: ** The second should be of type (void*). The callback is invoked by the library
1810: ** in three separate circumstances, identified by the value passed as the
1811: ** fourth parameter. If the fourth parameter is 0, then the database connection
1812: ** passed as the second argument has just been opened. The third argument
1813: ** points to a buffer containing the name of the main database file. If the
1814: ** fourth parameter is 1, then the SQL statement that the third parameter
1815: ** points to has just been executed. Or, if the fourth parameter is 2, then
1816: ** the connection being passed as the second parameter is being closed. The
1.4 misho 1817: ** third parameter is passed NULL In this case. An example of using this
1818: ** configuration option can be seen in the "test_sqllog.c" source file in
1819: ** the canonical SQLite source tree.</dd>
1820: **
1821: ** [[SQLITE_CONFIG_MMAP_SIZE]]
1822: ** <dt>SQLITE_CONFIG_MMAP_SIZE
1823: ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
1824: ** that are the default mmap size limit (the default setting for
1825: ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
1826: ** ^The default setting can be overridden by each database connection using
1827: ** either the [PRAGMA mmap_size] command, or by using the
1828: ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
1829: ** will be silently truncated if necessary so that it does not exceed the
1830: ** compile-time maximum mmap size set by the
1831: ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
1832: ** ^If either argument to this option is negative, then that argument is
1833: ** changed to its compile-time default.
1834: **
1835: ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
1836: ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
1837: ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
1838: ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
1839: ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
1840: ** that specifies the maximum size of the created heap.
1841: **
1842: ** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
1843: ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
1844: ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
1845: ** is a pointer to an integer and writes into that integer the number of extra
1846: ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
1847: ** The amount of extra space required can change depending on the compiler,
1848: ** target platform, and SQLite version.
1849: **
1850: ** [[SQLITE_CONFIG_PMASZ]]
1851: ** <dt>SQLITE_CONFIG_PMASZ
1852: ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
1853: ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
1854: ** sorter to that integer. The default minimum PMA Size is set by the
1855: ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched
1856: ** to help with sort operations when multithreaded sorting
1857: ** is enabled (using the [PRAGMA threads] command) and the amount of content
1858: ** to be sorted exceeds the page size times the minimum of the
1859: ** [PRAGMA cache_size] setting and this value.
1860: **
1861: ** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
1862: ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
1863: ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
1864: ** becomes the [statement journal] spill-to-disk threshold.
1865: ** [Statement journals] are held in memory until their size (in bytes)
1866: ** exceeds this threshold, at which point they are written to disk.
1867: ** Or if the threshold is -1, statement journals are always held
1868: ** exclusively in memory.
1869: ** Since many statement journals never become large, setting the spill
1870: ** threshold to a value such as 64KiB can greatly reduce the amount of
1871: ** I/O required to support statement rollback.
1872: ** The default value for this setting is controlled by the
1873: ** [SQLITE_STMTJRNL_SPILL] compile-time option.
1.3 misho 1874: ** </dl>
1.2 misho 1875: */
1876: #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
1877: #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
1878: #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
1879: #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
1880: #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1881: #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
1882: #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
1883: #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
1884: #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
1885: #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
1886: #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
1887: /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
1888: #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
1889: #define SQLITE_CONFIG_PCACHE 14 /* no-op */
1890: #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
1891: #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
1892: #define SQLITE_CONFIG_URI 17 /* int */
1893: #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
1894: #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
1.3 misho 1895: #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
1896: #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
1.4 misho 1897: #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
1898: #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
1899: #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */
1900: #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */
1901: #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */
1.2 misho 1902:
1903: /*
1904: ** CAPI3REF: Database Connection Configuration Options
1905: **
1906: ** These constants are the available integer configuration options that
1907: ** can be passed as the second argument to the [sqlite3_db_config()] interface.
1908: **
1909: ** New configuration options may be added in future releases of SQLite.
1910: ** Existing configuration options might be discontinued. Applications
1911: ** should check the return code from [sqlite3_db_config()] to make sure that
1912: ** the call worked. ^The [sqlite3_db_config()] interface will return a
1913: ** non-zero [error code] if a discontinued or unsupported configuration option
1914: ** is invoked.
1915: **
1916: ** <dl>
1917: ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1918: ** <dd> ^This option takes three additional arguments that determine the
1919: ** [lookaside memory allocator] configuration for the [database connection].
1920: ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
1921: ** pointer to a memory buffer to use for lookaside memory.
1922: ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1923: ** may be NULL in which case SQLite will allocate the
1924: ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1925: ** size of each lookaside buffer slot. ^The third argument is the number of
1926: ** slots. The size of the buffer in the first argument must be greater than
1927: ** or equal to the product of the second and third arguments. The buffer
1928: ** must be aligned to an 8-byte boundary. ^If the second argument to
1929: ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1930: ** rounded down to the next smaller multiple of 8. ^(The lookaside memory
1931: ** configuration for a database connection can only be changed when that
1932: ** connection is not currently using lookaside memory, or in other words
1933: ** when the "current value" returned by
1934: ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
1935: ** Any attempt to change the lookaside memory configuration when lookaside
1936: ** memory is in use leaves the configuration unchanged and returns
1937: ** [SQLITE_BUSY].)^</dd>
1938: **
1939: ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
1940: ** <dd> ^This option is used to enable or disable the enforcement of
1941: ** [foreign key constraints]. There should be two additional arguments.
1942: ** The first argument is an integer which is 0 to disable FK enforcement,
1943: ** positive to enable FK enforcement or negative to leave FK enforcement
1944: ** unchanged. The second parameter is a pointer to an integer into which
1945: ** is written 0 or 1 to indicate whether FK enforcement is off or on
1946: ** following this call. The second parameter may be a NULL pointer, in
1947: ** which case the FK enforcement setting is not reported back. </dd>
1948: **
1949: ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
1950: ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
1951: ** There should be two additional arguments.
1952: ** The first argument is an integer which is 0 to disable triggers,
1953: ** positive to enable triggers or negative to leave the setting unchanged.
1954: ** The second parameter is a pointer to an integer into which
1955: ** is written 0 or 1 to indicate whether triggers are disabled or enabled
1956: ** following this call. The second parameter may be a NULL pointer, in
1957: ** which case the trigger setting is not reported back. </dd>
1958: **
1.4 misho 1959: ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
1960: ** <dd> ^This option is used to enable or disable the two-argument
1961: ** version of the [fts3_tokenizer()] function which is part of the
1962: ** [FTS3] full-text search engine extension.
1963: ** There should be two additional arguments.
1964: ** The first argument is an integer which is 0 to disable fts3_tokenizer() or
1965: ** positive to enable fts3_tokenizer() or negative to leave the setting
1966: ** unchanged.
1967: ** The second parameter is a pointer to an integer into which
1968: ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
1969: ** following this call. The second parameter may be a NULL pointer, in
1970: ** which case the new setting is not reported back. </dd>
1971: **
1972: ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
1973: ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
1974: ** interface independently of the [load_extension()] SQL function.
1975: ** The [sqlite3_enable_load_extension()] API enables or disables both the
1976: ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
1977: ** There should be two additional arguments.
1978: ** When the first argument to this interface is 1, then only the C-API is
1979: ** enabled and the SQL function remains disabled. If the first argument to
1980: ** this interface is 0, then both the C-API and the SQL function are disabled.
1981: ** If the first argument is -1, then no changes are made to state of either the
1982: ** C-API or the SQL function.
1983: ** The second parameter is a pointer to an integer into which
1984: ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
1985: ** is disabled or enabled following this call. The second parameter may
1986: ** be a NULL pointer, in which case the new setting is not reported back.
1987: ** </dd>
1988: **
1.4.2.1 ! misho 1989: ** <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
! 1990: ** <dd> ^This option is used to change the name of the "main" database
! 1991: ** schema. ^The sole argument is a pointer to a constant UTF8 string
! 1992: ** which will become the new schema name in place of "main". ^SQLite
! 1993: ** does not make a copy of the new main schema name string, so the application
! 1994: ** must ensure that the argument passed into this DBCONFIG option is unchanged
! 1995: ** until after the database connection closes.
! 1996: ** </dd>
! 1997: **
! 1998: ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
! 1999: ** <dd> Usually, when a database in wal mode is closed or detached from a
! 2000: ** database handle, SQLite checks if this will mean that there are now no
! 2001: ** connections at all to the database. If so, it performs a checkpoint
! 2002: ** operation before closing the connection. This option may be used to
! 2003: ** override this behaviour. The first parameter passed to this operation
! 2004: ** is an integer - non-zero to disable checkpoints-on-close, or zero (the
! 2005: ** default) to enable them. The second parameter is a pointer to an integer
! 2006: ** into which is written 0 or 1 to indicate whether checkpoints-on-close
! 2007: ** have been disabled - 0 if they are not disabled, 1 if they are.
! 2008: ** </dd>
! 2009: **
1.2 misho 2010: ** </dl>
2011: */
1.4.2.1 ! misho 2012: #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */
1.4 misho 2013: #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
2014: #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
2015: #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
2016: #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2017: #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
1.4.2.1 ! misho 2018: #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */
1.2 misho 2019:
2020:
2021: /*
2022: ** CAPI3REF: Enable Or Disable Extended Result Codes
1.4 misho 2023: ** METHOD: sqlite3
1.2 misho 2024: **
2025: ** ^The sqlite3_extended_result_codes() routine enables or disables the
2026: ** [extended result codes] feature of SQLite. ^The extended result
2027: ** codes are disabled by default for historical compatibility.
2028: */
2029: SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2030:
2031: /*
2032: ** CAPI3REF: Last Insert Rowid
1.4 misho 2033: ** METHOD: sqlite3
1.2 misho 2034: **
1.4 misho 2035: ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2036: ** has a unique 64-bit signed
1.2 misho 2037: ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2038: ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2039: ** names are not also used by explicitly declared columns. ^If
2040: ** the table has a column of type [INTEGER PRIMARY KEY] then that column
2041: ** is another alias for the rowid.
2042: **
1.4.2.1 ! misho 2043: ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
! 2044: ** the most recent successful [INSERT] into a rowid table or [virtual table]
! 2045: ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
! 2046: ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
! 2047: ** on the database connection D, then sqlite3_last_insert_rowid(D) returns
! 2048: ** zero.
! 2049: **
! 2050: ** As well as being set automatically as rows are inserted into database
! 2051: ** tables, the value returned by this function may be set explicitly by
! 2052: ** [sqlite3_set_last_insert_rowid()]
! 2053: **
! 2054: ** Some virtual table implementations may INSERT rows into rowid tables as
! 2055: ** part of committing a transaction (e.g. to flush data accumulated in memory
! 2056: ** to disk). In this case subsequent calls to this function return the rowid
! 2057: ** associated with these internal INSERT operations, which leads to
! 2058: ** unintuitive results. Virtual table implementations that do write to rowid
! 2059: ** tables in this way can avoid this problem by restoring the original
! 2060: ** rowid value using [sqlite3_set_last_insert_rowid()] before returning
! 2061: ** control to the user.
! 2062: **
! 2063: ** ^(If an [INSERT] occurs within a trigger then this routine will
! 2064: ** return the [rowid] of the inserted row as long as the trigger is
! 2065: ** running. Once the trigger program ends, the value returned
! 2066: ** by this routine reverts to what it was before the trigger was fired.)^
1.2 misho 2067: **
2068: ** ^An [INSERT] that fails due to a constraint violation is not a
2069: ** successful [INSERT] and does not change the value returned by this
2070: ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2071: ** and INSERT OR ABORT make no changes to the return value of this
2072: ** routine when their insertion fails. ^(When INSERT OR REPLACE
2073: ** encounters a constraint violation, it does not fail. The
2074: ** INSERT continues to completion after deleting rows that caused
2075: ** the constraint problem so INSERT OR REPLACE will always change
2076: ** the return value of this interface.)^
2077: **
2078: ** ^For the purposes of this routine, an [INSERT] is considered to
2079: ** be successful even if it is subsequently rolled back.
2080: **
2081: ** This function is accessible to SQL statements via the
2082: ** [last_insert_rowid() SQL function].
2083: **
2084: ** If a separate thread performs a new [INSERT] on the same
2085: ** database connection while the [sqlite3_last_insert_rowid()]
2086: ** function is running and thus changes the last insert [rowid],
2087: ** then the value returned by [sqlite3_last_insert_rowid()] is
2088: ** unpredictable and might not equal either the old or the new
2089: ** last insert [rowid].
2090: */
2091: SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2092:
2093: /*
1.4.2.1 ! misho 2094: ** CAPI3REF: Set the Last Insert Rowid value.
! 2095: ** METHOD: sqlite3
! 2096: **
! 2097: ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
! 2098: ** set the value returned by calling sqlite3_last_insert_rowid(D) to R
! 2099: ** without inserting a row into the database.
! 2100: */
! 2101: SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
! 2102:
! 2103: /*
1.2 misho 2104: ** CAPI3REF: Count The Number Of Rows Modified
1.4 misho 2105: ** METHOD: sqlite3
1.2 misho 2106: **
1.4 misho 2107: ** ^This function returns the number of rows modified, inserted or
2108: ** deleted by the most recently completed INSERT, UPDATE or DELETE
2109: ** statement on the database connection specified by the only parameter.
2110: ** ^Executing any other type of SQL statement does not modify the value
2111: ** returned by this function.
2112: **
2113: ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2114: ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2115: ** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2116: **
2117: ** Changes to a view that are intercepted by
2118: ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2119: ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2120: ** DELETE statement run on a view is always zero. Only changes made to real
2121: ** tables are counted.
2122: **
2123: ** Things are more complicated if the sqlite3_changes() function is
2124: ** executed while a trigger program is running. This may happen if the
2125: ** program uses the [changes() SQL function], or if some other callback
2126: ** function invokes sqlite3_changes() directly. Essentially:
2127: **
2128: ** <ul>
2129: ** <li> ^(Before entering a trigger program the value returned by
2130: ** sqlite3_changes() function is saved. After the trigger program
2131: ** has finished, the original value is restored.)^
2132: **
2133: ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2134: ** statement sets the value returned by sqlite3_changes()
2135: ** upon completion as normal. Of course, this value will not include
2136: ** any changes performed by sub-triggers, as the sqlite3_changes()
2137: ** value will be saved and restored after each sub-trigger has run.)^
2138: ** </ul>
2139: **
2140: ** ^This means that if the changes() SQL function (or similar) is used
2141: ** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2142: ** returns the value as set when the calling statement began executing.
2143: ** ^If it is used by the second or subsequent such statement within a trigger
2144: ** program, the value returned reflects the number of rows modified by the
2145: ** previous INSERT, UPDATE or DELETE statement within the same trigger.
1.2 misho 2146: **
2147: ** See also the [sqlite3_total_changes()] interface, the
2148: ** [count_changes pragma], and the [changes() SQL function].
2149: **
2150: ** If a separate thread makes changes on the same database connection
2151: ** while [sqlite3_changes()] is running then the value returned
2152: ** is unpredictable and not meaningful.
2153: */
2154: SQLITE_API int sqlite3_changes(sqlite3*);
2155:
2156: /*
2157: ** CAPI3REF: Total Number Of Rows Modified
1.4 misho 2158: ** METHOD: sqlite3
1.2 misho 2159: **
1.4 misho 2160: ** ^This function returns the total number of rows inserted, modified or
2161: ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2162: ** since the database connection was opened, including those executed as
2163: ** part of trigger programs. ^Executing any other type of SQL statement
2164: ** does not affect the value returned by sqlite3_total_changes().
2165: **
2166: ** ^Changes made as part of [foreign key actions] are included in the
2167: ** count, but those made as part of REPLACE constraint resolution are
2168: ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2169: ** are not counted.
2170: **
1.2 misho 2171: ** See also the [sqlite3_changes()] interface, the
2172: ** [count_changes pragma], and the [total_changes() SQL function].
2173: **
2174: ** If a separate thread makes changes on the same database connection
2175: ** while [sqlite3_total_changes()] is running then the value
2176: ** returned is unpredictable and not meaningful.
2177: */
2178: SQLITE_API int sqlite3_total_changes(sqlite3*);
2179:
2180: /*
2181: ** CAPI3REF: Interrupt A Long-Running Query
1.4 misho 2182: ** METHOD: sqlite3
1.2 misho 2183: **
2184: ** ^This function causes any pending database operation to abort and
2185: ** return at its earliest opportunity. This routine is typically
2186: ** called in response to a user action such as pressing "Cancel"
2187: ** or Ctrl-C where the user wants a long query operation to halt
2188: ** immediately.
2189: **
2190: ** ^It is safe to call this routine from a thread different from the
2191: ** thread that is currently running the database operation. But it
2192: ** is not safe to call this routine with a [database connection] that
2193: ** is closed or might close before sqlite3_interrupt() returns.
2194: **
2195: ** ^If an SQL operation is very nearly finished at the time when
2196: ** sqlite3_interrupt() is called, then it might not have an opportunity
2197: ** to be interrupted and might continue to completion.
2198: **
2199: ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2200: ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2201: ** that is inside an explicit transaction, then the entire transaction
2202: ** will be rolled back automatically.
2203: **
2204: ** ^The sqlite3_interrupt(D) call is in effect until all currently running
2205: ** SQL statements on [database connection] D complete. ^Any new SQL statements
2206: ** that are started after the sqlite3_interrupt() call and before the
2207: ** running statements reaches zero are interrupted as if they had been
2208: ** running prior to the sqlite3_interrupt() call. ^New SQL statements
2209: ** that are started after the running statement count reaches zero are
2210: ** not effected by the sqlite3_interrupt().
2211: ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2212: ** SQL statements is a no-op and has no effect on SQL statements
2213: ** that are started after the sqlite3_interrupt() call returns.
2214: */
2215: SQLITE_API void sqlite3_interrupt(sqlite3*);
2216:
2217: /*
2218: ** CAPI3REF: Determine If An SQL Statement Is Complete
2219: **
2220: ** These routines are useful during command-line input to determine if the
2221: ** currently entered text seems to form a complete SQL statement or
2222: ** if additional input is needed before sending the text into
2223: ** SQLite for parsing. ^These routines return 1 if the input string
2224: ** appears to be a complete SQL statement. ^A statement is judged to be
2225: ** complete if it ends with a semicolon token and is not a prefix of a
2226: ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
2227: ** string literals or quoted identifier names or comments are not
2228: ** independent tokens (they are part of the token in which they are
2229: ** embedded) and thus do not count as a statement terminator. ^Whitespace
2230: ** and comments that follow the final semicolon are ignored.
2231: **
2232: ** ^These routines return 0 if the statement is incomplete. ^If a
2233: ** memory allocation fails, then SQLITE_NOMEM is returned.
2234: **
2235: ** ^These routines do not parse the SQL statements thus
2236: ** will not detect syntactically incorrect SQL.
2237: **
2238: ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2239: ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2240: ** automatically by sqlite3_complete16(). If that initialization fails,
2241: ** then the return value from sqlite3_complete16() will be non-zero
2242: ** regardless of whether or not the input SQL is complete.)^
2243: **
2244: ** The input to [sqlite3_complete()] must be a zero-terminated
2245: ** UTF-8 string.
2246: **
2247: ** The input to [sqlite3_complete16()] must be a zero-terminated
2248: ** UTF-16 string in native byte order.
2249: */
2250: SQLITE_API int sqlite3_complete(const char *sql);
2251: SQLITE_API int sqlite3_complete16(const void *sql);
2252:
2253: /*
2254: ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
1.4 misho 2255: ** KEYWORDS: {busy-handler callback} {busy handler}
2256: ** METHOD: sqlite3
1.2 misho 2257: **
1.4 misho 2258: ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2259: ** that might be invoked with argument P whenever
2260: ** an attempt is made to access a database table associated with
2261: ** [database connection] D when another thread
2262: ** or process has the table locked.
2263: ** The sqlite3_busy_handler() interface is used to implement
2264: ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
1.2 misho 2265: **
1.4 misho 2266: ** ^If the busy callback is NULL, then [SQLITE_BUSY]
1.2 misho 2267: ** is returned immediately upon encountering the lock. ^If the busy callback
2268: ** is not NULL, then the callback might be invoked with two arguments.
2269: **
2270: ** ^The first argument to the busy handler is a copy of the void* pointer which
2271: ** is the third argument to sqlite3_busy_handler(). ^The second argument to
2272: ** the busy handler callback is the number of times that the busy handler has
1.4 misho 2273: ** been invoked previously for the same locking event. ^If the
1.2 misho 2274: ** busy callback returns 0, then no additional attempts are made to
1.4 misho 2275: ** access the database and [SQLITE_BUSY] is returned
2276: ** to the application.
1.2 misho 2277: ** ^If the callback returns non-zero, then another attempt
1.4 misho 2278: ** is made to access the database and the cycle repeats.
1.2 misho 2279: **
2280: ** The presence of a busy handler does not guarantee that it will be invoked
2281: ** when there is lock contention. ^If SQLite determines that invoking the busy
2282: ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1.4 misho 2283: ** to the application instead of invoking the
2284: ** busy handler.
1.2 misho 2285: ** Consider a scenario where one process is holding a read lock that
2286: ** it is trying to promote to a reserved lock and
2287: ** a second process is holding a reserved lock that it is trying
2288: ** to promote to an exclusive lock. The first process cannot proceed
2289: ** because it is blocked by the second and the second process cannot
2290: ** proceed because it is blocked by the first. If both processes
2291: ** invoke the busy handlers, neither will make any progress. Therefore,
2292: ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2293: ** will induce the first process to release its read lock and allow
2294: ** the second process to proceed.
2295: **
2296: ** ^The default busy callback is NULL.
2297: **
2298: ** ^(There can only be a single busy handler defined for each
2299: ** [database connection]. Setting a new busy handler clears any
2300: ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
1.4 misho 2301: ** or evaluating [PRAGMA busy_timeout=N] will change the
2302: ** busy handler and thus clear any previously set busy handler.
1.2 misho 2303: **
2304: ** The busy callback should not take any actions which modify the
1.4 misho 2305: ** database connection that invoked the busy handler. In other words,
2306: ** the busy handler is not reentrant. Any such actions
1.2 misho 2307: ** result in undefined behavior.
2308: **
2309: ** A busy handler must not close the database connection
2310: ** or [prepared statement] that invoked the busy handler.
2311: */
1.4 misho 2312: SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
1.2 misho 2313:
2314: /*
2315: ** CAPI3REF: Set A Busy Timeout
1.4 misho 2316: ** METHOD: sqlite3
1.2 misho 2317: **
2318: ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2319: ** for a specified amount of time when a table is locked. ^The handler
2320: ** will sleep multiple times until at least "ms" milliseconds of sleeping
2321: ** have accumulated. ^After at least "ms" milliseconds of sleeping,
2322: ** the handler returns 0 which causes [sqlite3_step()] to return
1.4 misho 2323: ** [SQLITE_BUSY].
1.2 misho 2324: **
2325: ** ^Calling this routine with an argument less than or equal to zero
2326: ** turns off all busy handlers.
2327: **
2328: ** ^(There can only be a single busy handler for a particular
1.4 misho 2329: ** [database connection] at any given moment. If another busy handler
1.2 misho 2330: ** was defined (using [sqlite3_busy_handler()]) prior to calling
2331: ** this routine, that other busy handler is cleared.)^
1.4 misho 2332: **
2333: ** See also: [PRAGMA busy_timeout]
1.2 misho 2334: */
2335: SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
2336:
2337: /*
2338: ** CAPI3REF: Convenience Routines For Running Queries
1.4 misho 2339: ** METHOD: sqlite3
1.2 misho 2340: **
2341: ** This is a legacy interface that is preserved for backwards compatibility.
2342: ** Use of this interface is not recommended.
2343: **
2344: ** Definition: A <b>result table</b> is memory data structure created by the
2345: ** [sqlite3_get_table()] interface. A result table records the
2346: ** complete query results from one or more queries.
2347: **
2348: ** The table conceptually has a number of rows and columns. But
2349: ** these numbers are not part of the result table itself. These
2350: ** numbers are obtained separately. Let N be the number of rows
2351: ** and M be the number of columns.
2352: **
2353: ** A result table is an array of pointers to zero-terminated UTF-8 strings.
2354: ** There are (N+1)*M elements in the array. The first M pointers point
2355: ** to zero-terminated strings that contain the names of the columns.
2356: ** The remaining entries all point to query results. NULL values result
2357: ** in NULL pointers. All other values are in their UTF-8 zero-terminated
2358: ** string representation as returned by [sqlite3_column_text()].
2359: **
2360: ** A result table might consist of one or more memory allocations.
2361: ** It is not safe to pass a result table directly to [sqlite3_free()].
2362: ** A result table should be deallocated using [sqlite3_free_table()].
2363: **
2364: ** ^(As an example of the result table format, suppose a query result
2365: ** is as follows:
2366: **
2367: ** <blockquote><pre>
2368: ** Name | Age
2369: ** -----------------------
2370: ** Alice | 43
2371: ** Bob | 28
2372: ** Cindy | 21
2373: ** </pre></blockquote>
2374: **
2375: ** There are two column (M==2) and three rows (N==3). Thus the
2376: ** result table has 8 entries. Suppose the result table is stored
2377: ** in an array names azResult. Then azResult holds this content:
2378: **
2379: ** <blockquote><pre>
2380: ** azResult[0] = "Name";
2381: ** azResult[1] = "Age";
2382: ** azResult[2] = "Alice";
2383: ** azResult[3] = "43";
2384: ** azResult[4] = "Bob";
2385: ** azResult[5] = "28";
2386: ** azResult[6] = "Cindy";
2387: ** azResult[7] = "21";
2388: ** </pre></blockquote>)^
2389: **
2390: ** ^The sqlite3_get_table() function evaluates one or more
2391: ** semicolon-separated SQL statements in the zero-terminated UTF-8
2392: ** string of its 2nd parameter and returns a result table to the
2393: ** pointer given in its 3rd parameter.
2394: **
2395: ** After the application has finished with the result from sqlite3_get_table(),
2396: ** it must pass the result table pointer to sqlite3_free_table() in order to
2397: ** release the memory that was malloced. Because of the way the
2398: ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2399: ** function must not try to call [sqlite3_free()] directly. Only
2400: ** [sqlite3_free_table()] is able to release the memory properly and safely.
2401: **
2402: ** The sqlite3_get_table() interface is implemented as a wrapper around
2403: ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
2404: ** to any internal data structures of SQLite. It uses only the public
2405: ** interface defined here. As a consequence, errors that occur in the
2406: ** wrapper layer outside of the internal [sqlite3_exec()] call are not
2407: ** reflected in subsequent calls to [sqlite3_errcode()] or
2408: ** [sqlite3_errmsg()].
2409: */
2410: SQLITE_API int sqlite3_get_table(
2411: sqlite3 *db, /* An open database */
2412: const char *zSql, /* SQL to be evaluated */
2413: char ***pazResult, /* Results of the query */
2414: int *pnRow, /* Number of result rows written here */
2415: int *pnColumn, /* Number of result columns written here */
2416: char **pzErrmsg /* Error msg written here */
2417: );
2418: SQLITE_API void sqlite3_free_table(char **result);
2419:
2420: /*
2421: ** CAPI3REF: Formatted String Printing Functions
2422: **
2423: ** These routines are work-alikes of the "printf()" family of functions
2424: ** from the standard C library.
1.4 misho 2425: ** These routines understand most of the common K&R formatting options,
2426: ** plus some additional non-standard formats, detailed below.
2427: ** Note that some of the more obscure formatting options from recent
2428: ** C-library standards are omitted from this implementation.
1.2 misho 2429: **
2430: ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2431: ** results into memory obtained from [sqlite3_malloc()].
2432: ** The strings returned by these two routines should be
2433: ** released by [sqlite3_free()]. ^Both routines return a
2434: ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
2435: ** memory to hold the resulting string.
2436: **
2437: ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2438: ** the standard C library. The result is written into the
2439: ** buffer supplied as the second parameter whose size is given by
2440: ** the first parameter. Note that the order of the
2441: ** first two parameters is reversed from snprintf().)^ This is an
2442: ** historical accident that cannot be fixed without breaking
2443: ** backwards compatibility. ^(Note also that sqlite3_snprintf()
2444: ** returns a pointer to its buffer instead of the number of
2445: ** characters actually written into the buffer.)^ We admit that
2446: ** the number of characters written would be a more useful return
2447: ** value but we cannot change the implementation of sqlite3_snprintf()
2448: ** now without breaking compatibility.
2449: **
2450: ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2451: ** guarantees that the buffer is always zero-terminated. ^The first
2452: ** parameter "n" is the total size of the buffer, including space for
2453: ** the zero terminator. So the longest string that can be completely
2454: ** written will be n-1 characters.
2455: **
2456: ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2457: **
2458: ** These routines all implement some additional formatting
2459: ** options that are useful for constructing SQL statements.
2460: ** All of the usual printf() formatting options apply. In addition, there
1.4 misho 2461: ** is are "%q", "%Q", "%w" and "%z" options.
1.2 misho 2462: **
2463: ** ^(The %q option works like %s in that it substitutes a nul-terminated
2464: ** string from the argument list. But %q also doubles every '\'' character.
2465: ** %q is designed for use inside a string literal.)^ By doubling each '\''
2466: ** character it escapes that character and allows it to be inserted into
2467: ** the string.
2468: **
2469: ** For example, assume the string variable zText contains text as follows:
2470: **
2471: ** <blockquote><pre>
2472: ** char *zText = "It's a happy day!";
2473: ** </pre></blockquote>
2474: **
2475: ** One can use this text in an SQL statement as follows:
2476: **
2477: ** <blockquote><pre>
2478: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
2479: ** sqlite3_exec(db, zSQL, 0, 0, 0);
2480: ** sqlite3_free(zSQL);
2481: ** </pre></blockquote>
2482: **
2483: ** Because the %q format string is used, the '\'' character in zText
2484: ** is escaped and the SQL generated is as follows:
2485: **
2486: ** <blockquote><pre>
2487: ** INSERT INTO table1 VALUES('It''s a happy day!')
2488: ** </pre></blockquote>
2489: **
2490: ** This is correct. Had we used %s instead of %q, the generated SQL
2491: ** would have looked like this:
2492: **
2493: ** <blockquote><pre>
2494: ** INSERT INTO table1 VALUES('It's a happy day!');
2495: ** </pre></blockquote>
2496: **
2497: ** This second example is an SQL syntax error. As a general rule you should
2498: ** always use %q instead of %s when inserting text into a string literal.
2499: **
2500: ** ^(The %Q option works like %q except it also adds single quotes around
2501: ** the outside of the total string. Additionally, if the parameter in the
2502: ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
2503: ** single quotes).)^ So, for example, one could say:
2504: **
2505: ** <blockquote><pre>
2506: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
2507: ** sqlite3_exec(db, zSQL, 0, 0, 0);
2508: ** sqlite3_free(zSQL);
2509: ** </pre></blockquote>
2510: **
2511: ** The code above will render a correct SQL statement in the zSQL
2512: ** variable even if the zText variable is a NULL pointer.
2513: **
1.4 misho 2514: ** ^(The "%w" formatting option is like "%q" except that it expects to
2515: ** be contained within double-quotes instead of single quotes, and it
2516: ** escapes the double-quote character instead of the single-quote
2517: ** character.)^ The "%w" formatting option is intended for safely inserting
2518: ** table and column names into a constructed SQL statement.
2519: **
1.2 misho 2520: ** ^(The "%z" formatting option works like "%s" but with the
2521: ** addition that after the string has been read and copied into
2522: ** the result, [sqlite3_free()] is called on the input string.)^
2523: */
2524: SQLITE_API char *sqlite3_mprintf(const char*,...);
2525: SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
2526: SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
2527: SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
2528:
2529: /*
2530: ** CAPI3REF: Memory Allocation Subsystem
2531: **
2532: ** The SQLite core uses these three routines for all of its own
2533: ** internal memory allocation needs. "Core" in the previous sentence
2534: ** does not include operating-system specific VFS implementation. The
2535: ** Windows VFS uses native malloc() and free() for some operations.
2536: **
2537: ** ^The sqlite3_malloc() routine returns a pointer to a block
2538: ** of memory at least N bytes in length, where N is the parameter.
2539: ** ^If sqlite3_malloc() is unable to obtain sufficient free
2540: ** memory, it returns a NULL pointer. ^If the parameter N to
2541: ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2542: ** a NULL pointer.
2543: **
1.4 misho 2544: ** ^The sqlite3_malloc64(N) routine works just like
2545: ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
2546: ** of a signed 32-bit integer.
2547: **
1.2 misho 2548: ** ^Calling sqlite3_free() with a pointer previously returned
2549: ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2550: ** that it might be reused. ^The sqlite3_free() routine is
2551: ** a no-op if is called with a NULL pointer. Passing a NULL pointer
2552: ** to sqlite3_free() is harmless. After being freed, memory
2553: ** should neither be read nor written. Even reading previously freed
2554: ** memory might result in a segmentation fault or other severe error.
2555: ** Memory corruption, a segmentation fault, or other severe error
2556: ** might result if sqlite3_free() is called with a non-NULL pointer that
2557: ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2558: **
1.4 misho 2559: ** ^The sqlite3_realloc(X,N) interface attempts to resize a
2560: ** prior memory allocation X to be at least N bytes.
2561: ** ^If the X parameter to sqlite3_realloc(X,N)
1.2 misho 2562: ** is a NULL pointer then its behavior is identical to calling
1.4 misho 2563: ** sqlite3_malloc(N).
2564: ** ^If the N parameter to sqlite3_realloc(X,N) is zero or
1.2 misho 2565: ** negative then the behavior is exactly the same as calling
1.4 misho 2566: ** sqlite3_free(X).
2567: ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
2568: ** of at least N bytes in size or NULL if insufficient memory is available.
1.2 misho 2569: ** ^If M is the size of the prior allocation, then min(N,M) bytes
2570: ** of the prior allocation are copied into the beginning of buffer returned
1.4 misho 2571: ** by sqlite3_realloc(X,N) and the prior allocation is freed.
2572: ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
2573: ** prior allocation is not freed.
2574: **
2575: ** ^The sqlite3_realloc64(X,N) interfaces works the same as
2576: ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
2577: ** of a 32-bit signed integer.
2578: **
2579: ** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
2580: ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
2581: ** sqlite3_msize(X) returns the size of that memory allocation in bytes.
2582: ** ^The value returned by sqlite3_msize(X) might be larger than the number
2583: ** of bytes requested when X was allocated. ^If X is a NULL pointer then
2584: ** sqlite3_msize(X) returns zero. If X points to something that is not
2585: ** the beginning of memory allocation, or if it points to a formerly
2586: ** valid memory allocation that has now been freed, then the behavior
2587: ** of sqlite3_msize(X) is undefined and possibly harmful.
1.2 misho 2588: **
1.4 misho 2589: ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
2590: ** sqlite3_malloc64(), and sqlite3_realloc64()
1.2 misho 2591: ** is always aligned to at least an 8 byte boundary, or to a
2592: ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2593: ** option is used.
2594: **
2595: ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
2596: ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
2597: ** implementation of these routines to be omitted. That capability
2598: ** is no longer provided. Only built-in memory allocators can be used.
2599: **
1.3 misho 2600: ** Prior to SQLite version 3.7.10, the Windows OS interface layer called
1.2 misho 2601: ** the system malloc() and free() directly when converting
2602: ** filenames between the UTF-8 encoding used by SQLite
2603: ** and whatever filename encoding is used by the particular Windows
1.3 misho 2604: ** installation. Memory allocation errors were detected, but
2605: ** they were reported back as [SQLITE_CANTOPEN] or
1.2 misho 2606: ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
2607: **
2608: ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2609: ** must be either NULL or else pointers obtained from a prior
2610: ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2611: ** not yet been released.
2612: **
2613: ** The application must not read or write any part of
2614: ** a block of memory after it has been released using
2615: ** [sqlite3_free()] or [sqlite3_realloc()].
2616: */
2617: SQLITE_API void *sqlite3_malloc(int);
1.4 misho 2618: SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
1.2 misho 2619: SQLITE_API void *sqlite3_realloc(void*, int);
1.4 misho 2620: SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
1.2 misho 2621: SQLITE_API void sqlite3_free(void*);
1.4 misho 2622: SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
1.2 misho 2623:
2624: /*
2625: ** CAPI3REF: Memory Allocator Statistics
2626: **
2627: ** SQLite provides these two interfaces for reporting on the status
2628: ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2629: ** routines, which form the built-in memory allocation subsystem.
2630: **
2631: ** ^The [sqlite3_memory_used()] routine returns the number of bytes
2632: ** of memory currently outstanding (malloced but not freed).
2633: ** ^The [sqlite3_memory_highwater()] routine returns the maximum
2634: ** value of [sqlite3_memory_used()] since the high-water mark
2635: ** was last reset. ^The values returned by [sqlite3_memory_used()] and
2636: ** [sqlite3_memory_highwater()] include any overhead
2637: ** added by SQLite in its implementation of [sqlite3_malloc()],
2638: ** but not overhead added by the any underlying system library
2639: ** routines that [sqlite3_malloc()] may call.
2640: **
2641: ** ^The memory high-water mark is reset to the current value of
2642: ** [sqlite3_memory_used()] if and only if the parameter to
2643: ** [sqlite3_memory_highwater()] is true. ^The value returned
2644: ** by [sqlite3_memory_highwater(1)] is the high-water mark
2645: ** prior to the reset.
2646: */
2647: SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
2648: SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
2649:
2650: /*
2651: ** CAPI3REF: Pseudo-Random Number Generator
2652: **
2653: ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
2654: ** select random [ROWID | ROWIDs] when inserting new records into a table that
2655: ** already uses the largest possible [ROWID]. The PRNG is also used for
2656: ** the build-in random() and randomblob() SQL functions. This interface allows
2657: ** applications to access the same PRNG for other purposes.
2658: **
2659: ** ^A call to this routine stores N bytes of randomness into buffer P.
1.4 misho 2660: ** ^The P parameter can be a NULL pointer.
1.2 misho 2661: **
1.4 misho 2662: ** ^If this routine has not been previously called or if the previous
2663: ** call had N less than one or a NULL pointer for P, then the PRNG is
2664: ** seeded using randomness obtained from the xRandomness method of
2665: ** the default [sqlite3_vfs] object.
2666: ** ^If the previous call to this routine had an N of 1 or more and a
2667: ** non-NULL P then the pseudo-randomness is generated
1.2 misho 2668: ** internally and without recourse to the [sqlite3_vfs] xRandomness
2669: ** method.
2670: */
2671: SQLITE_API void sqlite3_randomness(int N, void *P);
2672:
2673: /*
2674: ** CAPI3REF: Compile-Time Authorization Callbacks
1.4 misho 2675: ** METHOD: sqlite3
1.4.2.1 ! misho 2676: ** KEYWORDS: {authorizer callback}
1.2 misho 2677: **
2678: ** ^This routine registers an authorizer callback with a particular
2679: ** [database connection], supplied in the first argument.
2680: ** ^The authorizer callback is invoked as SQL statements are being compiled
2681: ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
2682: ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
2683: ** points during the compilation process, as logic is being created
2684: ** to perform various actions, the authorizer callback is invoked to
2685: ** see if those actions are allowed. ^The authorizer callback should
2686: ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
2687: ** specific action but allow the SQL statement to continue to be
2688: ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2689: ** rejected with an error. ^If the authorizer callback returns
2690: ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2691: ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
2692: ** the authorizer will fail with an error message.
2693: **
2694: ** When the callback returns [SQLITE_OK], that means the operation
2695: ** requested is ok. ^When the callback returns [SQLITE_DENY], the
2696: ** [sqlite3_prepare_v2()] or equivalent call that triggered the
2697: ** authorizer will fail with an error message explaining that
2698: ** access is denied.
2699: **
2700: ** ^The first parameter to the authorizer callback is a copy of the third
2701: ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
2702: ** to the callback is an integer [SQLITE_COPY | action code] that specifies
2703: ** the particular action to be authorized. ^The third through sixth parameters
1.4.2.1 ! misho 2704: ** to the callback are either NULL pointers or zero-terminated strings
! 2705: ** that contain additional details about the action to be authorized.
! 2706: ** Applications must always be prepared to encounter a NULL pointer in any
! 2707: ** of the third through the sixth parameters of the authorization callback.
1.2 misho 2708: **
2709: ** ^If the action code is [SQLITE_READ]
2710: ** and the callback returns [SQLITE_IGNORE] then the
2711: ** [prepared statement] statement is constructed to substitute
2712: ** a NULL value in place of the table column that would have
2713: ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
2714: ** return can be used to deny an untrusted user access to individual
2715: ** columns of a table.
1.4.2.1 ! misho 2716: ** ^When a table is referenced by a [SELECT] but no column values are
! 2717: ** extracted from that table (for example in a query like
! 2718: ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
! 2719: ** is invoked once for that table with a column name that is an empty string.
1.2 misho 2720: ** ^If the action code is [SQLITE_DELETE] and the callback returns
2721: ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2722: ** [truncate optimization] is disabled and all rows are deleted individually.
2723: **
2724: ** An authorizer is used when [sqlite3_prepare | preparing]
2725: ** SQL statements from an untrusted source, to ensure that the SQL statements
2726: ** do not try to access data they are not allowed to see, or that they do not
2727: ** try to execute malicious statements that damage the database. For
2728: ** example, an application may allow a user to enter arbitrary
2729: ** SQL queries for evaluation by a database. But the application does
2730: ** not want the user to be able to make arbitrary changes to the
2731: ** database. An authorizer could then be put in place while the
2732: ** user-entered SQL is being [sqlite3_prepare | prepared] that
2733: ** disallows everything except [SELECT] statements.
2734: **
2735: ** Applications that need to process SQL from untrusted sources
2736: ** might also consider lowering resource limits using [sqlite3_limit()]
2737: ** and limiting database size using the [max_page_count] [PRAGMA]
2738: ** in addition to using an authorizer.
2739: **
2740: ** ^(Only a single authorizer can be in place on a database connection
2741: ** at a time. Each call to sqlite3_set_authorizer overrides the
2742: ** previous call.)^ ^Disable the authorizer by installing a NULL callback.
2743: ** The authorizer is disabled by default.
2744: **
2745: ** The authorizer callback must not do anything that will modify
2746: ** the database connection that invoked the authorizer callback.
2747: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2748: ** database connections for the meaning of "modify" in this paragraph.
2749: **
2750: ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
2751: ** statement might be re-prepared during [sqlite3_step()] due to a
2752: ** schema change. Hence, the application should ensure that the
2753: ** correct authorizer callback remains in place during the [sqlite3_step()].
2754: **
2755: ** ^Note that the authorizer callback is invoked only during
2756: ** [sqlite3_prepare()] or its variants. Authorization is not
2757: ** performed during statement evaluation in [sqlite3_step()], unless
2758: ** as stated in the previous paragraph, sqlite3_step() invokes
2759: ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
2760: */
2761: SQLITE_API int sqlite3_set_authorizer(
2762: sqlite3*,
2763: int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
2764: void *pUserData
2765: );
2766:
2767: /*
2768: ** CAPI3REF: Authorizer Return Codes
2769: **
2770: ** The [sqlite3_set_authorizer | authorizer callback function] must
2771: ** return either [SQLITE_OK] or one of these two constants in order
2772: ** to signal SQLite whether or not the action is permitted. See the
2773: ** [sqlite3_set_authorizer | authorizer documentation] for additional
2774: ** information.
2775: **
1.4 misho 2776: ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
2777: ** returned from the [sqlite3_vtab_on_conflict()] interface.
1.2 misho 2778: */
2779: #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
2780: #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
2781:
2782: /*
2783: ** CAPI3REF: Authorizer Action Codes
2784: **
2785: ** The [sqlite3_set_authorizer()] interface registers a callback function
2786: ** that is invoked to authorize certain SQL statement actions. The
2787: ** second parameter to the callback is an integer code that specifies
2788: ** what action is being authorized. These are the integer action codes that
2789: ** the authorizer callback may be passed.
2790: **
2791: ** These action code values signify what kind of operation is to be
2792: ** authorized. The 3rd and 4th parameters to the authorization
2793: ** callback function will be parameters or NULL depending on which of these
2794: ** codes is used as the second parameter. ^(The 5th parameter to the
2795: ** authorizer callback is the name of the database ("main", "temp",
2796: ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
2797: ** is the name of the inner-most trigger or view that is responsible for
2798: ** the access attempt or NULL if this access attempt is directly from
2799: ** top-level SQL code.
2800: */
2801: /******************************************* 3rd ************ 4th ***********/
2802: #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
2803: #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
2804: #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
2805: #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
2806: #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
2807: #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
2808: #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
2809: #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
2810: #define SQLITE_DELETE 9 /* Table Name NULL */
2811: #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
2812: #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
2813: #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
2814: #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
2815: #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
2816: #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
2817: #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
2818: #define SQLITE_DROP_VIEW 17 /* View Name NULL */
2819: #define SQLITE_INSERT 18 /* Table Name NULL */
2820: #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
2821: #define SQLITE_READ 20 /* Table Name Column Name */
2822: #define SQLITE_SELECT 21 /* NULL NULL */
2823: #define SQLITE_TRANSACTION 22 /* Operation NULL */
2824: #define SQLITE_UPDATE 23 /* Table Name Column Name */
2825: #define SQLITE_ATTACH 24 /* Filename NULL */
2826: #define SQLITE_DETACH 25 /* Database Name NULL */
2827: #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
2828: #define SQLITE_REINDEX 27 /* Index Name NULL */
2829: #define SQLITE_ANALYZE 28 /* Table Name NULL */
2830: #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
2831: #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
2832: #define SQLITE_FUNCTION 31 /* NULL Function Name */
2833: #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
2834: #define SQLITE_COPY 0 /* No longer used */
1.4 misho 2835: #define SQLITE_RECURSIVE 33 /* NULL NULL */
1.2 misho 2836:
2837: /*
2838: ** CAPI3REF: Tracing And Profiling Functions
1.4 misho 2839: ** METHOD: sqlite3
2840: **
2841: ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
2842: ** instead of the routines described here.
1.2 misho 2843: **
2844: ** These routines register callback functions that can be used for
2845: ** tracing and profiling the execution of SQL statements.
2846: **
2847: ** ^The callback function registered by sqlite3_trace() is invoked at
2848: ** various times when an SQL statement is being run by [sqlite3_step()].
2849: ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2850: ** SQL statement text as the statement first begins executing.
2851: ** ^(Additional sqlite3_trace() callbacks might occur
2852: ** as each triggered subprogram is entered. The callbacks for triggers
2853: ** contain a UTF-8 SQL comment that identifies the trigger.)^
2854: **
1.4 misho 2855: ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
2856: ** the length of [bound parameter] expansion in the output of sqlite3_trace().
2857: **
1.2 misho 2858: ** ^The callback function registered by sqlite3_profile() is invoked
2859: ** as each SQL statement finishes. ^The profile callback contains
2860: ** the original statement text and an estimate of wall-clock time
2861: ** of how long that statement took to run. ^The profile callback
2862: ** time is in units of nanoseconds, however the current implementation
2863: ** is only capable of millisecond resolution so the six least significant
2864: ** digits in the time are meaningless. Future versions of SQLite
2865: ** might provide greater resolution on the profiler callback. The
2866: ** sqlite3_profile() function is considered experimental and is
2867: ** subject to change in future versions of SQLite.
2868: */
1.4 misho 2869: SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
2870: void(*xTrace)(void*,const char*), void*);
2871: SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
1.2 misho 2872: void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
2873:
2874: /*
1.4 misho 2875: ** CAPI3REF: SQL Trace Event Codes
2876: ** KEYWORDS: SQLITE_TRACE
2877: **
2878: ** These constants identify classes of events that can be monitored
2879: ** using the [sqlite3_trace_v2()] tracing logic. The third argument
2880: ** to [sqlite3_trace_v2()] is an OR-ed combination of one or more of
2881: ** the following constants. ^The first argument to the trace callback
2882: ** is one of the following constants.
2883: **
2884: ** New tracing constants may be added in future releases.
2885: **
2886: ** ^A trace callback has four arguments: xCallback(T,C,P,X).
2887: ** ^The T argument is one of the integer type codes above.
2888: ** ^The C argument is a copy of the context pointer passed in as the
2889: ** fourth argument to [sqlite3_trace_v2()].
2890: ** The P and X arguments are pointers whose meanings depend on T.
2891: **
2892: ** <dl>
2893: ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
2894: ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
2895: ** first begins running and possibly at other times during the
2896: ** execution of the prepared statement, such as at the start of each
2897: ** trigger subprogram. ^The P argument is a pointer to the
2898: ** [prepared statement]. ^The X argument is a pointer to a string which
2899: ** is the unexpanded SQL text of the prepared statement or an SQL comment
2900: ** that indicates the invocation of a trigger. ^The callback can compute
2901: ** the same text that would have been returned by the legacy [sqlite3_trace()]
2902: ** interface by using the X argument when X begins with "--" and invoking
2903: ** [sqlite3_expanded_sql(P)] otherwise.
2904: **
2905: ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
2906: ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
2907: ** information as is provided by the [sqlite3_profile()] callback.
2908: ** ^The P argument is a pointer to the [prepared statement] and the
2909: ** X argument points to a 64-bit integer which is the estimated of
2910: ** the number of nanosecond that the prepared statement took to run.
2911: ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
2912: **
2913: ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
2914: ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
2915: ** statement generates a single row of result.
2916: ** ^The P argument is a pointer to the [prepared statement] and the
2917: ** X argument is unused.
2918: **
2919: ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
2920: ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
2921: ** connection closes.
2922: ** ^The P argument is a pointer to the [database connection] object
2923: ** and the X argument is unused.
2924: ** </dl>
2925: */
2926: #define SQLITE_TRACE_STMT 0x01
2927: #define SQLITE_TRACE_PROFILE 0x02
2928: #define SQLITE_TRACE_ROW 0x04
2929: #define SQLITE_TRACE_CLOSE 0x08
2930:
2931: /*
2932: ** CAPI3REF: SQL Trace Hook
2933: ** METHOD: sqlite3
2934: **
2935: ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
2936: ** function X against [database connection] D, using property mask M
2937: ** and context pointer P. ^If the X callback is
2938: ** NULL or if the M mask is zero, then tracing is disabled. The
2939: ** M argument should be the bitwise OR-ed combination of
2940: ** zero or more [SQLITE_TRACE] constants.
2941: **
2942: ** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides
2943: ** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
2944: **
2945: ** ^The X callback is invoked whenever any of the events identified by
2946: ** mask M occur. ^The integer return value from the callback is currently
2947: ** ignored, though this may change in future releases. Callback
2948: ** implementations should return zero to ensure future compatibility.
2949: **
2950: ** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
2951: ** ^The T argument is one of the [SQLITE_TRACE]
2952: ** constants to indicate why the callback was invoked.
2953: ** ^The C argument is a copy of the context pointer.
2954: ** The P and X arguments are pointers whose meanings depend on T.
2955: **
2956: ** The sqlite3_trace_v2() interface is intended to replace the legacy
2957: ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
2958: ** are deprecated.
2959: */
2960: SQLITE_API int sqlite3_trace_v2(
2961: sqlite3*,
2962: unsigned uMask,
2963: int(*xCallback)(unsigned,void*,void*,void*),
2964: void *pCtx
2965: );
2966:
2967: /*
1.2 misho 2968: ** CAPI3REF: Query Progress Callbacks
1.4 misho 2969: ** METHOD: sqlite3
1.2 misho 2970: **
2971: ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
2972: ** function X to be invoked periodically during long running calls to
2973: ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
2974: ** database connection D. An example use for this
2975: ** interface is to keep a GUI updated during a large query.
2976: **
2977: ** ^The parameter P is passed through as the only parameter to the
1.4 misho 2978: ** callback function X. ^The parameter N is the approximate number of
1.2 misho 2979: ** [virtual machine instructions] that are evaluated between successive
1.4 misho 2980: ** invocations of the callback X. ^If N is less than one then the progress
2981: ** handler is disabled.
1.2 misho 2982: **
2983: ** ^Only a single progress handler may be defined at one time per
2984: ** [database connection]; setting a new progress handler cancels the
2985: ** old one. ^Setting parameter X to NULL disables the progress handler.
2986: ** ^The progress handler is also disabled by setting N to a value less
2987: ** than 1.
2988: **
2989: ** ^If the progress callback returns non-zero, the operation is
2990: ** interrupted. This feature can be used to implement a
2991: ** "Cancel" button on a GUI progress dialog box.
2992: **
2993: ** The progress handler callback must not do anything that will modify
2994: ** the database connection that invoked the progress handler.
2995: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2996: ** database connections for the meaning of "modify" in this paragraph.
2997: **
2998: */
2999: SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3000:
3001: /*
3002: ** CAPI3REF: Opening A New Database Connection
1.4 misho 3003: ** CONSTRUCTOR: sqlite3
1.2 misho 3004: **
3005: ** ^These routines open an SQLite database file as specified by the
3006: ** filename argument. ^The filename argument is interpreted as UTF-8 for
3007: ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3008: ** order for sqlite3_open16(). ^(A [database connection] handle is usually
3009: ** returned in *ppDb, even if an error occurs. The only exception is that
3010: ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3011: ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3012: ** object.)^ ^(If the database is opened (and/or created) successfully, then
3013: ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
3014: ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3015: ** an English language description of the error following a failure of any
3016: ** of the sqlite3_open() routines.
3017: **
1.4 misho 3018: ** ^The default encoding will be UTF-8 for databases created using
3019: ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases
3020: ** created using sqlite3_open16() will be UTF-16 in the native byte order.
1.2 misho 3021: **
3022: ** Whether or not an error occurs when it is opened, resources
3023: ** associated with the [database connection] handle should be released by
3024: ** passing it to [sqlite3_close()] when it is no longer required.
3025: **
3026: ** The sqlite3_open_v2() interface works like sqlite3_open()
3027: ** except that it accepts two additional parameters for additional control
3028: ** over the new database connection. ^(The flags parameter to
3029: ** sqlite3_open_v2() can take one of
3030: ** the following three values, optionally combined with the
3031: ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
3032: ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
3033: **
3034: ** <dl>
3035: ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3036: ** <dd>The database is opened in read-only mode. If the database does not
3037: ** already exist, an error is returned.</dd>)^
3038: **
3039: ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3040: ** <dd>The database is opened for reading and writing if possible, or reading
3041: ** only if the file is write protected by the operating system. In either
3042: ** case the database must already exist, otherwise an error is returned.</dd>)^
3043: **
3044: ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3045: ** <dd>The database is opened for reading and writing, and is created if
3046: ** it does not already exist. This is the behavior that is always used for
3047: ** sqlite3_open() and sqlite3_open16().</dd>)^
3048: ** </dl>
3049: **
3050: ** If the 3rd parameter to sqlite3_open_v2() is not one of the
3051: ** combinations shown above optionally combined with other
3052: ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3053: ** then the behavior is undefined.
3054: **
3055: ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
3056: ** opens in the multi-thread [threading mode] as long as the single-thread
3057: ** mode has not been set at compile-time or start-time. ^If the
3058: ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
3059: ** in the serialized [threading mode] unless single-thread was
3060: ** previously selected at compile-time or start-time.
3061: ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
3062: ** eligible to use [shared cache mode], regardless of whether or not shared
3063: ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
3064: ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
3065: ** participate in [shared cache mode] even if it is enabled.
3066: **
3067: ** ^The fourth parameter to sqlite3_open_v2() is the name of the
3068: ** [sqlite3_vfs] object that defines the operating system interface that
3069: ** the new database connection should use. ^If the fourth parameter is
3070: ** a NULL pointer then the default [sqlite3_vfs] object is used.
3071: **
3072: ** ^If the filename is ":memory:", then a private, temporary in-memory database
3073: ** is created for the connection. ^This in-memory database will vanish when
3074: ** the database connection is closed. Future versions of SQLite might
3075: ** make use of additional special filenames that begin with the ":" character.
3076: ** It is recommended that when a database filename actually does begin with
3077: ** a ":" character you should prefix the filename with a pathname such as
3078: ** "./" to avoid ambiguity.
3079: **
3080: ** ^If the filename is an empty string, then a private, temporary
3081: ** on-disk database will be created. ^This private database will be
3082: ** automatically deleted as soon as the database connection is closed.
3083: **
3084: ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3085: **
3086: ** ^If [URI filename] interpretation is enabled, and the filename argument
3087: ** begins with "file:", then the filename is interpreted as a URI. ^URI
3088: ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3089: ** set in the fourth argument to sqlite3_open_v2(), or if it has
3090: ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3091: ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3092: ** As of SQLite version 3.7.7, URI filename interpretation is turned off
3093: ** by default, but future releases of SQLite might enable URI filename
3094: ** interpretation by default. See "[URI filenames]" for additional
3095: ** information.
3096: **
3097: ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3098: ** authority, then it must be either an empty string or the string
3099: ** "localhost". ^If the authority is not an empty string or "localhost", an
3100: ** error is returned to the caller. ^The fragment component of a URI, if
3101: ** present, is ignored.
3102: **
3103: ** ^SQLite uses the path component of the URI as the name of the disk file
3104: ** which contains the database. ^If the path begins with a '/' character,
3105: ** then it is interpreted as an absolute path. ^If the path does not begin
3106: ** with a '/' (meaning that the authority section is omitted from the URI)
3107: ** then the path is interpreted as a relative path.
1.4 misho 3108: ** ^(On windows, the first component of an absolute path
3109: ** is a drive specification (e.g. "C:").)^
1.2 misho 3110: **
3111: ** [[core URI query parameters]]
3112: ** The query component of a URI may contain parameters that are interpreted
3113: ** either by SQLite itself, or by a [VFS | custom VFS implementation].
1.4 misho 3114: ** SQLite and its built-in [VFSes] interpret the
3115: ** following query parameters:
1.2 misho 3116: **
3117: ** <ul>
3118: ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3119: ** a VFS object that provides the operating system interface that should
3120: ** be used to access the database file on disk. ^If this option is set to
3121: ** an empty string the default VFS object is used. ^Specifying an unknown
3122: ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3123: ** present, then the VFS specified by the option takes precedence over
3124: ** the value passed as the fourth parameter to sqlite3_open_v2().
3125: **
1.3 misho 3126: ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3127: ** "rwc", or "memory". Attempting to set it to any other value is
3128: ** an error)^.
1.2 misho 3129: ** ^If "ro" is specified, then the database is opened for read-only
3130: ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
1.3 misho 3131: ** third argument to sqlite3_open_v2(). ^If the mode option is set to
1.2 misho 3132: ** "rw", then the database is opened for read-write (but not create)
3133: ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3134: ** been set. ^Value "rwc" is equivalent to setting both
1.3 misho 3135: ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
3136: ** set to "memory" then a pure [in-memory database] that never reads
3137: ** or writes from disk is used. ^It is an error to specify a value for
3138: ** the mode parameter that is less restrictive than that specified by
3139: ** the flags passed in the third parameter to sqlite3_open_v2().
1.2 misho 3140: **
3141: ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3142: ** "private". ^Setting it to "shared" is equivalent to setting the
3143: ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3144: ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3145: ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3146: ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
1.4 misho 3147: ** a URI filename, its value overrides any behavior requested by setting
1.2 misho 3148: ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
1.4 misho 3149: **
3150: ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3151: ** [powersafe overwrite] property does or does not apply to the
3152: ** storage media on which the database file resides.
3153: **
3154: ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3155: ** which if set disables file locking in rollback journal modes. This
3156: ** is useful for accessing a database on a filesystem that does not
3157: ** support locking. Caution: Database corruption might result if two
3158: ** or more processes write to the same database and any one of those
3159: ** processes uses nolock=1.
3160: **
3161: ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3162: ** parameter that indicates that the database file is stored on
3163: ** read-only media. ^When immutable is set, SQLite assumes that the
3164: ** database file cannot be changed, even by a process with higher
3165: ** privilege, and so the database is opened read-only and all locking
3166: ** and change detection is disabled. Caution: Setting the immutable
3167: ** property on a database file that does in fact change can result
3168: ** in incorrect query results and/or [SQLITE_CORRUPT] errors.
3169: ** See also: [SQLITE_IOCAP_IMMUTABLE].
3170: **
1.2 misho 3171: ** </ul>
3172: **
3173: ** ^Specifying an unknown parameter in the query component of a URI is not an
3174: ** error. Future versions of SQLite might understand additional query
3175: ** parameters. See "[query parameters with special meaning to SQLite]" for
3176: ** additional information.
3177: **
3178: ** [[URI filename examples]] <h3>URI filename examples</h3>
3179: **
3180: ** <table border="1" align=center cellpadding=5>
3181: ** <tr><th> URI filenames <th> Results
3182: ** <tr><td> file:data.db <td>
3183: ** Open the file "data.db" in the current directory.
3184: ** <tr><td> file:/home/fred/data.db<br>
3185: ** file:///home/fred/data.db <br>
3186: ** file://localhost/home/fred/data.db <br> <td>
3187: ** Open the database file "/home/fred/data.db".
3188: ** <tr><td> file://darkstar/home/fred/data.db <td>
3189: ** An error. "darkstar" is not a recognized authority.
3190: ** <tr><td style="white-space:nowrap">
3191: ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3192: ** <td> Windows only: Open the file "data.db" on fred's desktop on drive
3193: ** C:. Note that the %20 escaping in this example is not strictly
3194: ** necessary - space characters can be used literally
3195: ** in URI filenames.
3196: ** <tr><td> file:data.db?mode=ro&cache=private <td>
3197: ** Open file "data.db" in the current directory for read-only access.
3198: ** Regardless of whether or not shared-cache mode is enabled by
3199: ** default, use a private cache.
1.4 misho 3200: ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3201: ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3202: ** that uses dot-files in place of posix advisory locking.
1.2 misho 3203: ** <tr><td> file:data.db?mode=readonly <td>
3204: ** An error. "readonly" is not a valid option for the "mode" parameter.
3205: ** </table>
3206: **
3207: ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3208: ** query components of a URI. A hexadecimal escape sequence consists of a
3209: ** percent sign - "%" - followed by exactly two hexadecimal digits
3210: ** specifying an octet value. ^Before the path or query components of a
3211: ** URI filename are interpreted, they are encoded using UTF-8 and all
3212: ** hexadecimal escape sequences replaced by a single byte containing the
3213: ** corresponding octet. If this process generates an invalid UTF-8 encoding,
3214: ** the results are undefined.
3215: **
3216: ** <b>Note to Windows users:</b> The encoding used for the filename argument
3217: ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3218: ** codepage is currently defined. Filenames containing international
3219: ** characters must be converted to UTF-8 prior to passing them into
3220: ** sqlite3_open() or sqlite3_open_v2().
1.3 misho 3221: **
3222: ** <b>Note to Windows Runtime users:</b> The temporary directory must be set
3223: ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
3224: ** features that require the use of temporary files may fail.
3225: **
3226: ** See also: [sqlite3_temp_directory]
1.2 misho 3227: */
3228: SQLITE_API int sqlite3_open(
3229: const char *filename, /* Database filename (UTF-8) */
3230: sqlite3 **ppDb /* OUT: SQLite db handle */
3231: );
3232: SQLITE_API int sqlite3_open16(
3233: const void *filename, /* Database filename (UTF-16) */
3234: sqlite3 **ppDb /* OUT: SQLite db handle */
3235: );
3236: SQLITE_API int sqlite3_open_v2(
3237: const char *filename, /* Database filename (UTF-8) */
3238: sqlite3 **ppDb, /* OUT: SQLite db handle */
3239: int flags, /* Flags */
3240: const char *zVfs /* Name of VFS module to use */
3241: );
3242:
3243: /*
3244: ** CAPI3REF: Obtain Values For URI Parameters
3245: **
3246: ** These are utility routines, useful to VFS implementations, that check
3247: ** to see if a database file was a URI that contained a specific query
3248: ** parameter, and if so obtains the value of that query parameter.
3249: **
3250: ** If F is the database filename pointer passed into the xOpen() method of
3251: ** a VFS implementation when the flags parameter to xOpen() has one or
3252: ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
3253: ** P is the name of the query parameter, then
3254: ** sqlite3_uri_parameter(F,P) returns the value of the P
3255: ** parameter if it exists or a NULL pointer if P does not appear as a
3256: ** query parameter on F. If P is a query parameter of F
3257: ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3258: ** a pointer to an empty string.
3259: **
3260: ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3261: ** parameter and returns true (1) or false (0) according to the value
1.3 misho 3262: ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3263: ** value of query parameter P is one of "yes", "true", or "on" in any
3264: ** case or if the value begins with a non-zero number. The
3265: ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3266: ** query parameter P is one of "no", "false", or "off" in any case or
3267: ** if the value begins with a numeric zero. If P is not a query
3268: ** parameter on F or if the value of P is does not match any of the
3269: ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
1.2 misho 3270: **
3271: ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3272: ** 64-bit signed integer and returns that integer, or D if P does not
3273: ** exist. If the value of P is something other than an integer, then
3274: ** zero is returned.
3275: **
3276: ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3277: ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
3278: ** is not a database file pathname pointer that SQLite passed into the xOpen
3279: ** VFS method, then the behavior of this routine is undefined and probably
3280: ** undesirable.
3281: */
3282: SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
3283: SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
3284: SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
3285:
3286:
3287: /*
3288: ** CAPI3REF: Error Codes And Messages
1.4 misho 3289: ** METHOD: sqlite3
1.2 misho 3290: **
1.4 misho 3291: ** ^If the most recent sqlite3_* API call associated with
3292: ** [database connection] D failed, then the sqlite3_errcode(D) interface
3293: ** returns the numeric [result code] or [extended result code] for that
3294: ** API call.
3295: ** If the most recent API call was successful,
3296: ** then the return value from sqlite3_errcode() is undefined.
3297: ** ^The sqlite3_extended_errcode()
1.2 misho 3298: ** interface is the same except that it always returns the
3299: ** [extended result code] even when extended result codes are
3300: ** disabled.
3301: **
3302: ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3303: ** text that describes the error, as either UTF-8 or UTF-16 respectively.
3304: ** ^(Memory to hold the error message string is managed internally.
3305: ** The application does not need to worry about freeing the result.
3306: ** However, the error string might be overwritten or deallocated by
3307: ** subsequent calls to other SQLite interface functions.)^
3308: **
1.3 misho 3309: ** ^The sqlite3_errstr() interface returns the English-language text
3310: ** that describes the [result code], as UTF-8.
3311: ** ^(Memory to hold the error message string is managed internally
3312: ** and must not be freed by the application)^.
3313: **
1.2 misho 3314: ** When the serialized [threading mode] is in use, it might be the
3315: ** case that a second error occurs on a separate thread in between
3316: ** the time of the first error and the call to these interfaces.
3317: ** When that happens, the second error will be reported since these
3318: ** interfaces always report the most recent result. To avoid
3319: ** this, each thread can obtain exclusive use of the [database connection] D
3320: ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3321: ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3322: ** all calls to the interfaces listed here are completed.
3323: **
3324: ** If an interface fails with SQLITE_MISUSE, that means the interface
3325: ** was invoked incorrectly by the application. In that case, the
3326: ** error code and message may or may not be set.
3327: */
3328: SQLITE_API int sqlite3_errcode(sqlite3 *db);
3329: SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
3330: SQLITE_API const char *sqlite3_errmsg(sqlite3*);
3331: SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
1.3 misho 3332: SQLITE_API const char *sqlite3_errstr(int);
1.2 misho 3333:
3334: /*
1.4 misho 3335: ** CAPI3REF: Prepared Statement Object
1.2 misho 3336: ** KEYWORDS: {prepared statement} {prepared statements}
3337: **
1.4 misho 3338: ** An instance of this object represents a single SQL statement that
3339: ** has been compiled into binary form and is ready to be evaluated.
3340: **
3341: ** Think of each SQL statement as a separate computer program. The
3342: ** original SQL text is source code. A prepared statement object
3343: ** is the compiled object code. All SQL must be converted into a
3344: ** prepared statement before it can be run.
1.2 misho 3345: **
1.4 misho 3346: ** The life-cycle of a prepared statement object usually goes like this:
1.2 misho 3347: **
3348: ** <ol>
1.4 misho 3349: ** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
3350: ** <li> Bind values to [parameters] using the sqlite3_bind_*()
1.2 misho 3351: ** interfaces.
3352: ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
1.4 misho 3353: ** <li> Reset the prepared statement using [sqlite3_reset()] then go back
1.2 misho 3354: ** to step 2. Do this zero or more times.
3355: ** <li> Destroy the object using [sqlite3_finalize()].
3356: ** </ol>
3357: */
3358: typedef struct sqlite3_stmt sqlite3_stmt;
3359:
3360: /*
3361: ** CAPI3REF: Run-time Limits
1.4 misho 3362: ** METHOD: sqlite3
1.2 misho 3363: **
3364: ** ^(This interface allows the size of various constructs to be limited
3365: ** on a connection by connection basis. The first parameter is the
3366: ** [database connection] whose limit is to be set or queried. The
3367: ** second parameter is one of the [limit categories] that define a
3368: ** class of constructs to be size limited. The third parameter is the
3369: ** new limit for that construct.)^
3370: **
3371: ** ^If the new limit is a negative number, the limit is unchanged.
3372: ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
3373: ** [limits | hard upper bound]
3374: ** set at compile-time by a C preprocessor macro called
3375: ** [limits | SQLITE_MAX_<i>NAME</i>].
3376: ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3377: ** ^Attempts to increase a limit above its hard upper bound are
3378: ** silently truncated to the hard upper bound.
3379: **
3380: ** ^Regardless of whether or not the limit was changed, the
3381: ** [sqlite3_limit()] interface returns the prior value of the limit.
3382: ** ^Hence, to find the current value of a limit without changing it,
3383: ** simply invoke this interface with the third parameter set to -1.
3384: **
3385: ** Run-time limits are intended for use in applications that manage
3386: ** both their own internal database and also databases that are controlled
3387: ** by untrusted external sources. An example application might be a
3388: ** web browser that has its own databases for storing history and
3389: ** separate databases controlled by JavaScript applications downloaded
3390: ** off the Internet. The internal databases can be given the
3391: ** large, default limits. Databases managed by external sources can
3392: ** be given much smaller limits designed to prevent a denial of service
3393: ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
3394: ** interface to further control untrusted SQL. The size of the database
3395: ** created by an untrusted script can be contained using the
3396: ** [max_page_count] [PRAGMA].
3397: **
3398: ** New run-time limit categories may be added in future releases.
3399: */
3400: SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
3401:
3402: /*
3403: ** CAPI3REF: Run-Time Limit Categories
3404: ** KEYWORDS: {limit category} {*limit categories}
3405: **
3406: ** These constants define various performance limits
3407: ** that can be lowered at run-time using [sqlite3_limit()].
3408: ** The synopsis of the meanings of the various limits is shown below.
3409: ** Additional information is available at [limits | Limits in SQLite].
3410: **
3411: ** <dl>
3412: ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3413: ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
3414: **
3415: ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3416: ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
3417: **
3418: ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
3419: ** <dd>The maximum number of columns in a table definition or in the
3420: ** result set of a [SELECT] or the maximum number of columns in an index
3421: ** or in an ORDER BY or GROUP BY clause.</dd>)^
3422: **
3423: ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3424: ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3425: **
3426: ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3427: ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3428: **
3429: ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3430: ** <dd>The maximum number of instructions in a virtual machine program
1.4.2.1 ! misho 3431: ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or
! 3432: ** the equivalent tries to allocate space for more than this many opcodes
! 3433: ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
1.2 misho 3434: **
3435: ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3436: ** <dd>The maximum number of arguments on a function.</dd>)^
3437: **
3438: ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3439: ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3440: **
3441: ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3442: ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3443: ** <dd>The maximum length of the pattern argument to the [LIKE] or
3444: ** [GLOB] operators.</dd>)^
3445: **
3446: ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3447: ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3448: ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3449: **
3450: ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3451: ** <dd>The maximum depth of recursion for triggers.</dd>)^
1.4 misho 3452: **
3453: ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
3454: ** <dd>The maximum number of auxiliary worker threads that a single
3455: ** [prepared statement] may start.</dd>)^
1.2 misho 3456: ** </dl>
3457: */
3458: #define SQLITE_LIMIT_LENGTH 0
3459: #define SQLITE_LIMIT_SQL_LENGTH 1
3460: #define SQLITE_LIMIT_COLUMN 2
3461: #define SQLITE_LIMIT_EXPR_DEPTH 3
3462: #define SQLITE_LIMIT_COMPOUND_SELECT 4
3463: #define SQLITE_LIMIT_VDBE_OP 5
3464: #define SQLITE_LIMIT_FUNCTION_ARG 6
3465: #define SQLITE_LIMIT_ATTACHED 7
3466: #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
3467: #define SQLITE_LIMIT_VARIABLE_NUMBER 9
3468: #define SQLITE_LIMIT_TRIGGER_DEPTH 10
1.4 misho 3469: #define SQLITE_LIMIT_WORKER_THREADS 11
1.2 misho 3470:
1.4.2.1 ! misho 3471:
1.2 misho 3472: /*
3473: ** CAPI3REF: Compiling An SQL Statement
3474: ** KEYWORDS: {SQL statement compiler}
1.4 misho 3475: ** METHOD: sqlite3
3476: ** CONSTRUCTOR: sqlite3_stmt
1.2 misho 3477: **
3478: ** To execute an SQL query, it must first be compiled into a byte-code
3479: ** program using one of these routines.
3480: **
3481: ** The first argument, "db", is a [database connection] obtained from a
3482: ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
3483: ** [sqlite3_open16()]. The database connection must not have been closed.
3484: **
3485: ** The second argument, "zSql", is the statement to be compiled, encoded
3486: ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
3487: ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
3488: ** use UTF-16.
3489: **
1.4 misho 3490: ** ^If the nByte argument is negative, then zSql is read up to the
3491: ** first zero terminator. ^If nByte is positive, then it is the
3492: ** number of bytes read from zSql. ^If nByte is zero, then no prepared
3493: ** statement is generated.
3494: ** If the caller knows that the supplied string is nul-terminated, then
3495: ** there is a small performance advantage to passing an nByte parameter that
3496: ** is the number of bytes in the input string <i>including</i>
3497: ** the nul-terminator.
1.2 misho 3498: **
3499: ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
3500: ** past the end of the first SQL statement in zSql. These routines only
3501: ** compile the first statement in zSql, so *pzTail is left pointing to
3502: ** what remains uncompiled.
3503: **
3504: ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
3505: ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
3506: ** to NULL. ^If the input text contains no SQL (if the input is an empty
3507: ** string or a comment) then *ppStmt is set to NULL.
3508: ** The calling procedure is responsible for deleting the compiled
3509: ** SQL statement using [sqlite3_finalize()] after it has finished with it.
3510: ** ppStmt may not be NULL.
3511: **
3512: ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
3513: ** otherwise an [error code] is returned.
3514: **
3515: ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
3516: ** recommended for all new programs. The two older interfaces are retained
3517: ** for backwards compatibility, but their use is discouraged.
3518: ** ^In the "v2" interfaces, the prepared statement
3519: ** that is returned (the [sqlite3_stmt] object) contains a copy of the
3520: ** original SQL text. This causes the [sqlite3_step()] interface to
3521: ** behave differently in three ways:
3522: **
3523: ** <ol>
3524: ** <li>
3525: ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
3526: ** always used to do, [sqlite3_step()] will automatically recompile the SQL
1.4 misho 3527: ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
3528: ** retries will occur before sqlite3_step() gives up and returns an error.
1.2 misho 3529: ** </li>
3530: **
3531: ** <li>
3532: ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
3533: ** [error codes] or [extended error codes]. ^The legacy behavior was that
3534: ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
3535: ** and the application would have to make a second call to [sqlite3_reset()]
3536: ** in order to find the underlying cause of the problem. With the "v2" prepare
3537: ** interfaces, the underlying reason for the error is returned immediately.
3538: ** </li>
3539: **
3540: ** <li>
3541: ** ^If the specific value bound to [parameter | host parameter] in the
3542: ** WHERE clause might influence the choice of query plan for a statement,
3543: ** then the statement will be automatically recompiled, as if there had been
3544: ** a schema change, on the first [sqlite3_step()] call following any change
3545: ** to the [sqlite3_bind_text | bindings] of that [parameter].
3546: ** ^The specific value of WHERE-clause [parameter] might influence the
3547: ** choice of query plan if the parameter is the left-hand side of a [LIKE]
3548: ** or [GLOB] operator or if the parameter is compared to an indexed column
3549: ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
3550: ** </li>
3551: ** </ol>
3552: */
3553: SQLITE_API int sqlite3_prepare(
3554: sqlite3 *db, /* Database handle */
3555: const char *zSql, /* SQL statement, UTF-8 encoded */
3556: int nByte, /* Maximum length of zSql in bytes. */
3557: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3558: const char **pzTail /* OUT: Pointer to unused portion of zSql */
3559: );
3560: SQLITE_API int sqlite3_prepare_v2(
3561: sqlite3 *db, /* Database handle */
3562: const char *zSql, /* SQL statement, UTF-8 encoded */
3563: int nByte, /* Maximum length of zSql in bytes. */
3564: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3565: const char **pzTail /* OUT: Pointer to unused portion of zSql */
3566: );
3567: SQLITE_API int sqlite3_prepare16(
3568: sqlite3 *db, /* Database handle */
3569: const void *zSql, /* SQL statement, UTF-16 encoded */
3570: int nByte, /* Maximum length of zSql in bytes. */
3571: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3572: const void **pzTail /* OUT: Pointer to unused portion of zSql */
3573: );
3574: SQLITE_API int sqlite3_prepare16_v2(
3575: sqlite3 *db, /* Database handle */
3576: const void *zSql, /* SQL statement, UTF-16 encoded */
3577: int nByte, /* Maximum length of zSql in bytes. */
3578: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3579: const void **pzTail /* OUT: Pointer to unused portion of zSql */
3580: );
3581:
3582: /*
3583: ** CAPI3REF: Retrieving Statement SQL
1.4 misho 3584: ** METHOD: sqlite3_stmt
1.2 misho 3585: **
1.4 misho 3586: ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
3587: ** SQL text used to create [prepared statement] P if P was
3588: ** created by either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
3589: ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
3590: ** string containing the SQL text of prepared statement P with
3591: ** [bound parameters] expanded.
3592: **
3593: ** ^(For example, if a prepared statement is created using the SQL
3594: ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
3595: ** and parameter :xyz is unbound, then sqlite3_sql() will return
3596: ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
3597: ** will return "SELECT 2345,NULL".)^
3598: **
3599: ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
3600: ** is available to hold the result, or if the result would exceed the
3601: ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
3602: **
3603: ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
3604: ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time
3605: ** option causes sqlite3_expanded_sql() to always return NULL.
3606: **
3607: ** ^The string returned by sqlite3_sql(P) is managed by SQLite and is
3608: ** automatically freed when the prepared statement is finalized.
3609: ** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
3610: ** is obtained from [sqlite3_malloc()] and must be free by the application
3611: ** by passing it to [sqlite3_free()].
1.2 misho 3612: */
3613: SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
1.4 misho 3614: SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
1.2 misho 3615:
3616: /*
3617: ** CAPI3REF: Determine If An SQL Statement Writes The Database
1.4 misho 3618: ** METHOD: sqlite3_stmt
1.2 misho 3619: **
3620: ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
3621: ** and only if the [prepared statement] X makes no direct changes to
3622: ** the content of the database file.
3623: **
3624: ** Note that [application-defined SQL functions] or
3625: ** [virtual tables] might change the database indirectly as a side effect.
3626: ** ^(For example, if an application defines a function "eval()" that
3627: ** calls [sqlite3_exec()], then the following SQL statement would
3628: ** change the database file through side-effects:
3629: **
3630: ** <blockquote><pre>
3631: ** SELECT eval('DELETE FROM t1') FROM t2;
3632: ** </pre></blockquote>
3633: **
3634: ** But because the [SELECT] statement does not change the database file
3635: ** directly, sqlite3_stmt_readonly() would still return true.)^
3636: **
3637: ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
3638: ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
3639: ** since the statements themselves do not actually modify the database but
3640: ** rather they control the timing of when other statements modify the
3641: ** database. ^The [ATTACH] and [DETACH] statements also cause
3642: ** sqlite3_stmt_readonly() to return true since, while those statements
3643: ** change the configuration of a database connection, they do not make
3644: ** changes to the content of the database files on disk.
1.4.2.1 ! misho 3645: ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
! 3646: ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
! 3647: ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
! 3648: ** sqlite3_stmt_readonly() returns false for those commands.
1.2 misho 3649: */
3650: SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
3651:
3652: /*
3653: ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
1.4 misho 3654: ** METHOD: sqlite3_stmt
1.2 misho 3655: **
3656: ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
3657: ** [prepared statement] S has been stepped at least once using
1.4 misho 3658: ** [sqlite3_step(S)] but has neither run to completion (returned
3659: ** [SQLITE_DONE] from [sqlite3_step(S)]) nor
1.2 misho 3660: ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
3661: ** interface returns false if S is a NULL pointer. If S is not a
3662: ** NULL pointer and is not a pointer to a valid [prepared statement]
3663: ** object, then the behavior is undefined and probably undesirable.
3664: **
3665: ** This interface can be used in combination [sqlite3_next_stmt()]
3666: ** to locate all prepared statements associated with a database
3667: ** connection that are in need of being reset. This can be used,
3668: ** for example, in diagnostic routines to search for prepared
3669: ** statements that are holding a transaction open.
3670: */
3671: SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
3672:
3673: /*
3674: ** CAPI3REF: Dynamically Typed Value Object
3675: ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
3676: **
3677: ** SQLite uses the sqlite3_value object to represent all values
3678: ** that can be stored in a database table. SQLite uses dynamic typing
3679: ** for the values it stores. ^Values stored in sqlite3_value objects
3680: ** can be integers, floating point values, strings, BLOBs, or NULL.
3681: **
3682: ** An sqlite3_value object may be either "protected" or "unprotected".
3683: ** Some interfaces require a protected sqlite3_value. Other interfaces
3684: ** will accept either a protected or an unprotected sqlite3_value.
3685: ** Every interface that accepts sqlite3_value arguments specifies
1.4 misho 3686: ** whether or not it requires a protected sqlite3_value. The
3687: ** [sqlite3_value_dup()] interface can be used to construct a new
3688: ** protected sqlite3_value from an unprotected sqlite3_value.
1.2 misho 3689: **
3690: ** The terms "protected" and "unprotected" refer to whether or not
3691: ** a mutex is held. An internal mutex is held for a protected
3692: ** sqlite3_value object but no mutex is held for an unprotected
3693: ** sqlite3_value object. If SQLite is compiled to be single-threaded
3694: ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
3695: ** or if SQLite is run in one of reduced mutex modes
3696: ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
3697: ** then there is no distinction between protected and unprotected
3698: ** sqlite3_value objects and they can be used interchangeably. However,
3699: ** for maximum code portability it is recommended that applications
3700: ** still make the distinction between protected and unprotected
3701: ** sqlite3_value objects even when not strictly required.
3702: **
3703: ** ^The sqlite3_value objects that are passed as parameters into the
3704: ** implementation of [application-defined SQL functions] are protected.
3705: ** ^The sqlite3_value object returned by
3706: ** [sqlite3_column_value()] is unprotected.
3707: ** Unprotected sqlite3_value objects may only be used with
3708: ** [sqlite3_result_value()] and [sqlite3_bind_value()].
3709: ** The [sqlite3_value_blob | sqlite3_value_type()] family of
3710: ** interfaces require protected sqlite3_value objects.
3711: */
1.4.2.1 ! misho 3712: typedef struct sqlite3_value sqlite3_value;
1.2 misho 3713:
3714: /*
3715: ** CAPI3REF: SQL Function Context Object
3716: **
3717: ** The context in which an SQL function executes is stored in an
3718: ** sqlite3_context object. ^A pointer to an sqlite3_context object
3719: ** is always first parameter to [application-defined SQL functions].
3720: ** The application-defined SQL function implementation will pass this
3721: ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
3722: ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
3723: ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
3724: ** and/or [sqlite3_set_auxdata()].
3725: */
3726: typedef struct sqlite3_context sqlite3_context;
3727:
3728: /*
3729: ** CAPI3REF: Binding Values To Prepared Statements
3730: ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
3731: ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
1.4 misho 3732: ** METHOD: sqlite3_stmt
1.2 misho 3733: **
3734: ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
3735: ** literals may be replaced by a [parameter] that matches one of following
3736: ** templates:
3737: **
3738: ** <ul>
3739: ** <li> ?
3740: ** <li> ?NNN
3741: ** <li> :VVV
3742: ** <li> @VVV
3743: ** <li> $VVV
3744: ** </ul>
3745: **
3746: ** In the templates above, NNN represents an integer literal,
3747: ** and VVV represents an alphanumeric identifier.)^ ^The values of these
3748: ** parameters (also called "host parameter names" or "SQL parameters")
3749: ** can be set using the sqlite3_bind_*() routines defined here.
3750: **
3751: ** ^The first argument to the sqlite3_bind_*() routines is always
3752: ** a pointer to the [sqlite3_stmt] object returned from
3753: ** [sqlite3_prepare_v2()] or its variants.
3754: **
3755: ** ^The second argument is the index of the SQL parameter to be set.
3756: ** ^The leftmost SQL parameter has an index of 1. ^When the same named
3757: ** SQL parameter is used more than once, second and subsequent
3758: ** occurrences have the same index as the first occurrence.
3759: ** ^The index for named parameters can be looked up using the
3760: ** [sqlite3_bind_parameter_index()] API if desired. ^The index
3761: ** for "?NNN" parameters is the value of NNN.
3762: ** ^The NNN value must be between 1 and the [sqlite3_limit()]
3763: ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
3764: **
3765: ** ^The third argument is the value to bind to the parameter.
1.4 misho 3766: ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3767: ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
3768: ** is ignored and the end result is the same as sqlite3_bind_null().
1.2 misho 3769: **
3770: ** ^(In those routines that have a fourth argument, its value is the
3771: ** number of bytes in the parameter. To be clear: the value is the
3772: ** number of <u>bytes</u> in the value, not the number of characters.)^
1.3 misho 3773: ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3774: ** is negative, then the length of the string is
1.2 misho 3775: ** the number of bytes up to the first zero terminator.
1.3 misho 3776: ** If the fourth parameter to sqlite3_bind_blob() is negative, then
3777: ** the behavior is undefined.
1.2 misho 3778: ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
1.4 misho 3779: ** or sqlite3_bind_text16() or sqlite3_bind_text64() then
3780: ** that parameter must be the byte offset
1.2 misho 3781: ** where the NUL terminator would occur assuming the string were NUL
3782: ** terminated. If any NUL characters occur at byte offsets less than
3783: ** the value of the fourth parameter then the resulting string value will
3784: ** contain embedded NULs. The result of expressions involving strings
3785: ** with embedded NULs is undefined.
3786: **
1.4 misho 3787: ** ^The fifth argument to the BLOB and string binding interfaces
3788: ** is a destructor used to dispose of the BLOB or
1.2 misho 3789: ** string after SQLite has finished with it. ^The destructor is called
1.4 misho 3790: ** to dispose of the BLOB or string even if the call to bind API fails.
1.2 misho 3791: ** ^If the fifth argument is
3792: ** the special value [SQLITE_STATIC], then SQLite assumes that the
3793: ** information is in static, unmanaged space and does not need to be freed.
3794: ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
3795: ** SQLite makes its own private copy of the data immediately, before
3796: ** the sqlite3_bind_*() routine returns.
3797: **
1.4 misho 3798: ** ^The sixth argument to sqlite3_bind_text64() must be one of
3799: ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
3800: ** to specify the encoding of the text in the third parameter. If
3801: ** the sixth argument to sqlite3_bind_text64() is not one of the
3802: ** allowed values shown above, or if the text encoding is different
3803: ** from the encoding specified by the sixth parameter, then the behavior
3804: ** is undefined.
3805: **
1.2 misho 3806: ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
3807: ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
3808: ** (just an integer to hold its size) while it is being processed.
3809: ** Zeroblobs are intended to serve as placeholders for BLOBs whose
3810: ** content is later written using
3811: ** [sqlite3_blob_open | incremental BLOB I/O] routines.
3812: ** ^A negative value for the zeroblob results in a zero-length BLOB.
3813: **
3814: ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
3815: ** for the [prepared statement] or with a prepared statement for which
3816: ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
3817: ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
3818: ** routine is passed a [prepared statement] that has been finalized, the
3819: ** result is undefined and probably harmful.
3820: **
3821: ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
3822: ** ^Unbound parameters are interpreted as NULL.
3823: **
3824: ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
3825: ** [error code] if anything goes wrong.
1.4 misho 3826: ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
3827: ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
3828: ** [SQLITE_MAX_LENGTH].
1.2 misho 3829: ** ^[SQLITE_RANGE] is returned if the parameter
3830: ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
3831: **
3832: ** See also: [sqlite3_bind_parameter_count()],
3833: ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
3834: */
3835: SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
1.4 misho 3836: SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
3837: void(*)(void*));
1.2 misho 3838: SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
3839: SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
3840: SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
3841: SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
1.4 misho 3842: SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
1.2 misho 3843: SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
1.4 misho 3844: SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
3845: void(*)(void*), unsigned char encoding);
1.2 misho 3846: SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
3847: SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
1.4 misho 3848: SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
1.2 misho 3849:
3850: /*
3851: ** CAPI3REF: Number Of SQL Parameters
1.4 misho 3852: ** METHOD: sqlite3_stmt
1.2 misho 3853: **
3854: ** ^This routine can be used to find the number of [SQL parameters]
3855: ** in a [prepared statement]. SQL parameters are tokens of the
3856: ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
3857: ** placeholders for values that are [sqlite3_bind_blob | bound]
3858: ** to the parameters at a later time.
3859: **
3860: ** ^(This routine actually returns the index of the largest (rightmost)
3861: ** parameter. For all forms except ?NNN, this will correspond to the
3862: ** number of unique parameters. If parameters of the ?NNN form are used,
3863: ** there may be gaps in the list.)^
3864: **
3865: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3866: ** [sqlite3_bind_parameter_name()], and
3867: ** [sqlite3_bind_parameter_index()].
3868: */
3869: SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
3870:
3871: /*
3872: ** CAPI3REF: Name Of A Host Parameter
1.4 misho 3873: ** METHOD: sqlite3_stmt
1.2 misho 3874: **
3875: ** ^The sqlite3_bind_parameter_name(P,N) interface returns
3876: ** the name of the N-th [SQL parameter] in the [prepared statement] P.
3877: ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
3878: ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
3879: ** respectively.
3880: ** In other words, the initial ":" or "$" or "@" or "?"
3881: ** is included as part of the name.)^
3882: ** ^Parameters of the form "?" without a following integer have no name
3883: ** and are referred to as "nameless" or "anonymous parameters".
3884: **
3885: ** ^The first host parameter has an index of 1, not 0.
3886: **
3887: ** ^If the value N is out of range or if the N-th parameter is
3888: ** nameless, then NULL is returned. ^The returned string is
3889: ** always in UTF-8 encoding even if the named parameter was
3890: ** originally specified as UTF-16 in [sqlite3_prepare16()] or
3891: ** [sqlite3_prepare16_v2()].
3892: **
3893: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3894: ** [sqlite3_bind_parameter_count()], and
3895: ** [sqlite3_bind_parameter_index()].
3896: */
3897: SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
3898:
3899: /*
3900: ** CAPI3REF: Index Of A Parameter With A Given Name
1.4 misho 3901: ** METHOD: sqlite3_stmt
1.2 misho 3902: **
3903: ** ^Return the index of an SQL parameter given its name. ^The
3904: ** index value returned is suitable for use as the second
3905: ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
3906: ** is returned if no matching parameter is found. ^The parameter
3907: ** name must be given in UTF-8 even if the original statement
3908: ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
3909: **
3910: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3911: ** [sqlite3_bind_parameter_count()], and
1.4 misho 3912: ** [sqlite3_bind_parameter_name()].
1.2 misho 3913: */
3914: SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
3915:
3916: /*
3917: ** CAPI3REF: Reset All Bindings On A Prepared Statement
1.4 misho 3918: ** METHOD: sqlite3_stmt
1.2 misho 3919: **
3920: ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
3921: ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
3922: ** ^Use this routine to reset all host parameters to NULL.
3923: */
3924: SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
3925:
3926: /*
3927: ** CAPI3REF: Number Of Columns In A Result Set
1.4 misho 3928: ** METHOD: sqlite3_stmt
1.2 misho 3929: **
3930: ** ^Return the number of columns in the result set returned by the
1.4.2.1 ! misho 3931: ** [prepared statement]. ^If this routine returns 0, that means the
! 3932: ** [prepared statement] returns no data (for example an [UPDATE]).
! 3933: ** ^However, just because this routine returns a positive number does not
! 3934: ** mean that one or more rows of data will be returned. ^A SELECT statement
! 3935: ** will always have a positive sqlite3_column_count() but depending on the
! 3936: ** WHERE clause constraints and the table content, it might return no rows.
1.2 misho 3937: **
3938: ** See also: [sqlite3_data_count()]
3939: */
3940: SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
3941:
3942: /*
3943: ** CAPI3REF: Column Names In A Result Set
1.4 misho 3944: ** METHOD: sqlite3_stmt
1.2 misho 3945: **
3946: ** ^These routines return the name assigned to a particular column
3947: ** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
3948: ** interface returns a pointer to a zero-terminated UTF-8 string
3949: ** and sqlite3_column_name16() returns a pointer to a zero-terminated
3950: ** UTF-16 string. ^The first parameter is the [prepared statement]
3951: ** that implements the [SELECT] statement. ^The second parameter is the
3952: ** column number. ^The leftmost column is number 0.
3953: **
3954: ** ^The returned string pointer is valid until either the [prepared statement]
3955: ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
3956: ** reprepared by the first call to [sqlite3_step()] for a particular run
3957: ** or until the next call to
3958: ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
3959: **
3960: ** ^If sqlite3_malloc() fails during the processing of either routine
3961: ** (for example during a conversion from UTF-8 to UTF-16) then a
3962: ** NULL pointer is returned.
3963: **
3964: ** ^The name of a result column is the value of the "AS" clause for
3965: ** that column, if there is an AS clause. If there is no AS clause
3966: ** then the name of the column is unspecified and may change from
3967: ** one release of SQLite to the next.
3968: */
3969: SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
3970: SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
3971:
3972: /*
3973: ** CAPI3REF: Source Of Data In A Query Result
1.4 misho 3974: ** METHOD: sqlite3_stmt
1.2 misho 3975: **
3976: ** ^These routines provide a means to determine the database, table, and
3977: ** table column that is the origin of a particular result column in
3978: ** [SELECT] statement.
3979: ** ^The name of the database or table or column can be returned as
3980: ** either a UTF-8 or UTF-16 string. ^The _database_ routines return
3981: ** the database name, the _table_ routines return the table name, and
3982: ** the origin_ routines return the column name.
3983: ** ^The returned string is valid until the [prepared statement] is destroyed
3984: ** using [sqlite3_finalize()] or until the statement is automatically
3985: ** reprepared by the first call to [sqlite3_step()] for a particular run
3986: ** or until the same information is requested
3987: ** again in a different encoding.
3988: **
3989: ** ^The names returned are the original un-aliased names of the
3990: ** database, table, and column.
3991: **
3992: ** ^The first argument to these interfaces is a [prepared statement].
3993: ** ^These functions return information about the Nth result column returned by
3994: ** the statement, where N is the second function argument.
3995: ** ^The left-most column is column 0 for these routines.
3996: **
3997: ** ^If the Nth column returned by the statement is an expression or
3998: ** subquery and is not a column value, then all of these functions return
3999: ** NULL. ^These routine might also return NULL if a memory allocation error
4000: ** occurs. ^Otherwise, they return the name of the attached database, table,
4001: ** or column that query result column was extracted from.
4002: **
4003: ** ^As with all other SQLite APIs, those whose names end with "16" return
4004: ** UTF-16 encoded strings and the other functions return UTF-8.
4005: **
4006: ** ^These APIs are only available if the library was compiled with the
4007: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
4008: **
4009: ** If two or more threads call one or more of these routines against the same
4010: ** prepared statement and column at the same time then the results are
4011: ** undefined.
4012: **
4013: ** If two or more threads call one or more
4014: ** [sqlite3_column_database_name | column metadata interfaces]
4015: ** for the same [prepared statement] and result column
4016: ** at the same time then the results are undefined.
4017: */
4018: SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
4019: SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
4020: SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
4021: SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
4022: SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
4023: SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
4024:
4025: /*
4026: ** CAPI3REF: Declared Datatype Of A Query Result
1.4 misho 4027: ** METHOD: sqlite3_stmt
1.2 misho 4028: **
4029: ** ^(The first parameter is a [prepared statement].
4030: ** If this statement is a [SELECT] statement and the Nth column of the
4031: ** returned result set of that [SELECT] is a table column (not an
4032: ** expression or subquery) then the declared type of the table
4033: ** column is returned.)^ ^If the Nth column of the result set is an
4034: ** expression or subquery, then a NULL pointer is returned.
4035: ** ^The returned string is always UTF-8 encoded.
4036: **
4037: ** ^(For example, given the database schema:
4038: **
4039: ** CREATE TABLE t1(c1 VARIANT);
4040: **
4041: ** and the following statement to be compiled:
4042: **
4043: ** SELECT c1 + 1, c1 FROM t1;
4044: **
4045: ** this routine would return the string "VARIANT" for the second result
4046: ** column (i==1), and a NULL pointer for the first result column (i==0).)^
4047: **
4048: ** ^SQLite uses dynamic run-time typing. ^So just because a column
4049: ** is declared to contain a particular type does not mean that the
4050: ** data stored in that column is of the declared type. SQLite is
4051: ** strongly typed, but the typing is dynamic not static. ^Type
4052: ** is associated with individual values, not with the containers
4053: ** used to hold those values.
4054: */
4055: SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
4056: SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
4057:
4058: /*
4059: ** CAPI3REF: Evaluate An SQL Statement
1.4 misho 4060: ** METHOD: sqlite3_stmt
1.2 misho 4061: **
4062: ** After a [prepared statement] has been prepared using either
4063: ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
4064: ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4065: ** must be called one or more times to evaluate the statement.
4066: **
4067: ** The details of the behavior of the sqlite3_step() interface depend
4068: ** on whether the statement was prepared using the newer "v2" interface
4069: ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
4070: ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
4071: ** new "v2" interface is recommended for new applications but the legacy
4072: ** interface will continue to be supported.
4073: **
4074: ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4075: ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4076: ** ^With the "v2" interface, any of the other [result codes] or
4077: ** [extended result codes] might be returned as well.
4078: **
4079: ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4080: ** database locks it needs to do its job. ^If the statement is a [COMMIT]
4081: ** or occurs outside of an explicit transaction, then you can retry the
4082: ** statement. If the statement is not a [COMMIT] and occurs within an
4083: ** explicit transaction then you should rollback the transaction before
4084: ** continuing.
4085: **
4086: ** ^[SQLITE_DONE] means that the statement has finished executing
4087: ** successfully. sqlite3_step() should not be called again on this virtual
4088: ** machine without first calling [sqlite3_reset()] to reset the virtual
4089: ** machine back to its initial state.
4090: **
4091: ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4092: ** is returned each time a new row of data is ready for processing by the
4093: ** caller. The values may be accessed using the [column access functions].
4094: ** sqlite3_step() is called again to retrieve the next row of data.
4095: **
4096: ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4097: ** violation) has occurred. sqlite3_step() should not be called again on
4098: ** the VM. More information may be found by calling [sqlite3_errmsg()].
4099: ** ^With the legacy interface, a more specific error code (for example,
4100: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4101: ** can be obtained by calling [sqlite3_reset()] on the
4102: ** [prepared statement]. ^In the "v2" interface,
4103: ** the more specific error code is returned directly by sqlite3_step().
4104: **
4105: ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4106: ** Perhaps it was called on a [prepared statement] that has
4107: ** already been [sqlite3_finalize | finalized] or on one that had
4108: ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
4109: ** be the case that the same database connection is being used by two or
4110: ** more threads at the same moment in time.
4111: **
4112: ** For all versions of SQLite up to and including 3.6.23.1, a call to
4113: ** [sqlite3_reset()] was required after sqlite3_step() returned anything
4114: ** other than [SQLITE_ROW] before any subsequent invocation of
4115: ** sqlite3_step(). Failure to reset the prepared statement using
4116: ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
1.4.2.1 ! misho 4117: ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1],
! 4118: ** sqlite3_step() began
1.2 misho 4119: ** calling [sqlite3_reset()] automatically in this circumstance rather
4120: ** than returning [SQLITE_MISUSE]. This is not considered a compatibility
4121: ** break because any application that ever receives an SQLITE_MISUSE error
4122: ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
4123: ** can be used to restore the legacy behavior.
4124: **
4125: ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
4126: ** API always returns a generic error code, [SQLITE_ERROR], following any
4127: ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
4128: ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
4129: ** specific [error codes] that better describes the error.
4130: ** We admit that this is a goofy design. The problem has been fixed
4131: ** with the "v2" interface. If you prepare all of your SQL statements
4132: ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
4133: ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
4134: ** then the more specific [error codes] are returned directly
4135: ** by sqlite3_step(). The use of the "v2" interface is recommended.
4136: */
4137: SQLITE_API int sqlite3_step(sqlite3_stmt*);
4138:
4139: /*
4140: ** CAPI3REF: Number of columns in a result set
1.4 misho 4141: ** METHOD: sqlite3_stmt
1.2 misho 4142: **
4143: ** ^The sqlite3_data_count(P) interface returns the number of columns in the
4144: ** current row of the result set of [prepared statement] P.
4145: ** ^If prepared statement P does not have results ready to return
4146: ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
4147: ** interfaces) then sqlite3_data_count(P) returns 0.
4148: ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
4149: ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
4150: ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
4151: ** will return non-zero if previous call to [sqlite3_step](P) returned
4152: ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
4153: ** where it always returns zero since each step of that multi-step
4154: ** pragma returns 0 columns of data.
4155: **
4156: ** See also: [sqlite3_column_count()]
4157: */
4158: SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
4159:
4160: /*
4161: ** CAPI3REF: Fundamental Datatypes
4162: ** KEYWORDS: SQLITE_TEXT
4163: **
4164: ** ^(Every value in SQLite has one of five fundamental datatypes:
4165: **
4166: ** <ul>
4167: ** <li> 64-bit signed integer
4168: ** <li> 64-bit IEEE floating point number
4169: ** <li> string
4170: ** <li> BLOB
4171: ** <li> NULL
4172: ** </ul>)^
4173: **
4174: ** These constants are codes for each of those types.
4175: **
4176: ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
4177: ** for a completely different meaning. Software that links against both
4178: ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
4179: ** SQLITE_TEXT.
4180: */
4181: #define SQLITE_INTEGER 1
4182: #define SQLITE_FLOAT 2
4183: #define SQLITE_BLOB 4
4184: #define SQLITE_NULL 5
4185: #ifdef SQLITE_TEXT
4186: # undef SQLITE_TEXT
4187: #else
4188: # define SQLITE_TEXT 3
4189: #endif
4190: #define SQLITE3_TEXT 3
4191:
4192: /*
4193: ** CAPI3REF: Result Values From A Query
4194: ** KEYWORDS: {column access functions}
1.4 misho 4195: ** METHOD: sqlite3_stmt
1.2 misho 4196: **
4197: ** ^These routines return information about a single column of the current
4198: ** result row of a query. ^In every case the first argument is a pointer
4199: ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
4200: ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
4201: ** and the second argument is the index of the column for which information
4202: ** should be returned. ^The leftmost column of the result set has the index 0.
4203: ** ^The number of columns in the result can be determined using
4204: ** [sqlite3_column_count()].
4205: **
4206: ** If the SQL statement does not currently point to a valid row, or if the
4207: ** column index is out of range, the result is undefined.
4208: ** These routines may only be called when the most recent call to
4209: ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
4210: ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
4211: ** If any of these routines are called after [sqlite3_reset()] or
4212: ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
4213: ** something other than [SQLITE_ROW], the results are undefined.
4214: ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
4215: ** are called from a different thread while any of these routines
4216: ** are pending, then the results are undefined.
4217: **
4218: ** ^The sqlite3_column_type() routine returns the
4219: ** [SQLITE_INTEGER | datatype code] for the initial data type
4220: ** of the result column. ^The returned value is one of [SQLITE_INTEGER],
4221: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
4222: ** returned by sqlite3_column_type() is only meaningful if no type
4223: ** conversions have occurred as described below. After a type conversion,
4224: ** the value returned by sqlite3_column_type() is undefined. Future
4225: ** versions of SQLite may change the behavior of sqlite3_column_type()
4226: ** following a type conversion.
4227: **
4228: ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
4229: ** routine returns the number of bytes in that BLOB or string.
4230: ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
4231: ** the string to UTF-8 and then returns the number of bytes.
4232: ** ^If the result is a numeric value then sqlite3_column_bytes() uses
4233: ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
4234: ** the number of bytes in that string.
4235: ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
4236: **
4237: ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
4238: ** routine returns the number of bytes in that BLOB or string.
4239: ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
4240: ** the string to UTF-16 and then returns the number of bytes.
4241: ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
4242: ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
4243: ** the number of bytes in that string.
4244: ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
4245: **
4246: ** ^The values returned by [sqlite3_column_bytes()] and
4247: ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
4248: ** of the string. ^For clarity: the values returned by
4249: ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
4250: ** bytes in the string, not the number of characters.
4251: **
4252: ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
4253: ** even empty strings, are always zero-terminated. ^The return
4254: ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
4255: **
1.4 misho 4256: ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
4257: ** [unprotected sqlite3_value] object. In a multithreaded environment,
4258: ** an unprotected sqlite3_value object may only be used safely with
4259: ** [sqlite3_bind_value()] and [sqlite3_result_value()].
1.2 misho 4260: ** If the [unprotected sqlite3_value] object returned by
4261: ** [sqlite3_column_value()] is used in any other way, including calls
4262: ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
1.4 misho 4263: ** or [sqlite3_value_bytes()], the behavior is not threadsafe.
1.2 misho 4264: **
4265: ** These routines attempt to convert the value where appropriate. ^For
4266: ** example, if the internal representation is FLOAT and a text result
4267: ** is requested, [sqlite3_snprintf()] is used internally to perform the
4268: ** conversion automatically. ^(The following table details the conversions
4269: ** that are applied:
4270: **
4271: ** <blockquote>
4272: ** <table border="1">
4273: ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
4274: **
4275: ** <tr><td> NULL <td> INTEGER <td> Result is 0
4276: ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
1.4 misho 4277: ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer
4278: ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer
1.2 misho 4279: ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
4280: ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
4281: ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
1.4 misho 4282: ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER
1.2 misho 4283: ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
1.4 misho 4284: ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB
4285: ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER
4286: ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL
1.2 misho 4287: ** <tr><td> TEXT <td> BLOB <td> No change
1.4 misho 4288: ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER
4289: ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL
1.2 misho 4290: ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
4291: ** </table>
4292: ** </blockquote>)^
4293: **
4294: ** Note that when type conversions occur, pointers returned by prior
4295: ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
4296: ** sqlite3_column_text16() may be invalidated.
4297: ** Type conversions and pointer invalidations might occur
4298: ** in the following cases:
4299: **
4300: ** <ul>
4301: ** <li> The initial content is a BLOB and sqlite3_column_text() or
4302: ** sqlite3_column_text16() is called. A zero-terminator might
4303: ** need to be added to the string.</li>
4304: ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
4305: ** sqlite3_column_text16() is called. The content must be converted
4306: ** to UTF-16.</li>
4307: ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
4308: ** sqlite3_column_text() is called. The content must be converted
4309: ** to UTF-8.</li>
4310: ** </ul>
4311: **
4312: ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
4313: ** not invalidate a prior pointer, though of course the content of the buffer
4314: ** that the prior pointer references will have been modified. Other kinds
4315: ** of conversion are done in place when it is possible, but sometimes they
4316: ** are not possible and in those cases prior pointers are invalidated.
4317: **
1.4 misho 4318: ** The safest policy is to invoke these routines
1.2 misho 4319: ** in one of the following ways:
4320: **
4321: ** <ul>
4322: ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
4323: ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
4324: ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
4325: ** </ul>
4326: **
4327: ** In other words, you should call sqlite3_column_text(),
4328: ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
4329: ** into the desired format, then invoke sqlite3_column_bytes() or
4330: ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
4331: ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
4332: ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
4333: ** with calls to sqlite3_column_bytes().
4334: **
4335: ** ^The pointers returned are valid until a type conversion occurs as
4336: ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
4337: ** [sqlite3_finalize()] is called. ^The memory space used to hold strings
1.4 misho 4338: ** and BLOBs is freed automatically. Do <em>not</em> pass the pointers returned
4339: ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
1.2 misho 4340: ** [sqlite3_free()].
4341: **
4342: ** ^(If a memory allocation error occurs during the evaluation of any
4343: ** of these routines, a default value is returned. The default value
4344: ** is either the integer 0, the floating point number 0.0, or a NULL
4345: ** pointer. Subsequent calls to [sqlite3_errcode()] will return
4346: ** [SQLITE_NOMEM].)^
4347: */
4348: SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
4349: SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
4350: SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
4351: SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
4352: SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
4353: SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
4354: SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
4355: SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
4356: SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
4357: SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
4358:
4359: /*
4360: ** CAPI3REF: Destroy A Prepared Statement Object
1.4 misho 4361: ** DESTRUCTOR: sqlite3_stmt
1.2 misho 4362: **
4363: ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
4364: ** ^If the most recent evaluation of the statement encountered no errors
4365: ** or if the statement is never been evaluated, then sqlite3_finalize() returns
4366: ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
4367: ** sqlite3_finalize(S) returns the appropriate [error code] or
4368: ** [extended error code].
4369: **
4370: ** ^The sqlite3_finalize(S) routine can be called at any point during
4371: ** the life cycle of [prepared statement] S:
4372: ** before statement S is ever evaluated, after
4373: ** one or more calls to [sqlite3_reset()], or after any call
4374: ** to [sqlite3_step()] regardless of whether or not the statement has
4375: ** completed execution.
4376: **
4377: ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
4378: **
4379: ** The application must finalize every [prepared statement] in order to avoid
4380: ** resource leaks. It is a grievous error for the application to try to use
4381: ** a prepared statement after it has been finalized. Any use of a prepared
4382: ** statement after it has been finalized can result in undefined and
4383: ** undesirable behavior such as segfaults and heap corruption.
4384: */
4385: SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
4386:
4387: /*
4388: ** CAPI3REF: Reset A Prepared Statement Object
1.4 misho 4389: ** METHOD: sqlite3_stmt
1.2 misho 4390: **
4391: ** The sqlite3_reset() function is called to reset a [prepared statement]
4392: ** object back to its initial state, ready to be re-executed.
4393: ** ^Any SQL statement variables that had values bound to them using
4394: ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
4395: ** Use [sqlite3_clear_bindings()] to reset the bindings.
4396: **
4397: ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
4398: ** back to the beginning of its program.
4399: **
4400: ** ^If the most recent call to [sqlite3_step(S)] for the
4401: ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
4402: ** or if [sqlite3_step(S)] has never before been called on S,
4403: ** then [sqlite3_reset(S)] returns [SQLITE_OK].
4404: **
4405: ** ^If the most recent call to [sqlite3_step(S)] for the
4406: ** [prepared statement] S indicated an error, then
4407: ** [sqlite3_reset(S)] returns an appropriate [error code].
4408: **
4409: ** ^The [sqlite3_reset(S)] interface does not change the values
4410: ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
4411: */
4412: SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
4413:
4414: /*
4415: ** CAPI3REF: Create Or Redefine SQL Functions
4416: ** KEYWORDS: {function creation routines}
4417: ** KEYWORDS: {application-defined SQL function}
4418: ** KEYWORDS: {application-defined SQL functions}
1.4 misho 4419: ** METHOD: sqlite3
1.2 misho 4420: **
4421: ** ^These functions (collectively known as "function creation routines")
4422: ** are used to add SQL functions or aggregates or to redefine the behavior
4423: ** of existing SQL functions or aggregates. The only differences between
4424: ** these routines are the text encoding expected for
4425: ** the second parameter (the name of the function being created)
4426: ** and the presence or absence of a destructor callback for
4427: ** the application data pointer.
4428: **
4429: ** ^The first parameter is the [database connection] to which the SQL
4430: ** function is to be added. ^If an application uses more than one database
4431: ** connection then application-defined SQL functions must be added
4432: ** to each database connection separately.
4433: **
4434: ** ^The second parameter is the name of the SQL function to be created or
4435: ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
4436: ** representation, exclusive of the zero-terminator. ^Note that the name
4437: ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
4438: ** ^Any attempt to create a function with a longer name
4439: ** will result in [SQLITE_MISUSE] being returned.
4440: **
4441: ** ^The third parameter (nArg)
4442: ** is the number of arguments that the SQL function or
4443: ** aggregate takes. ^If this parameter is -1, then the SQL function or
4444: ** aggregate may take any number of arguments between 0 and the limit
4445: ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
4446: ** parameter is less than -1 or greater than 127 then the behavior is
4447: ** undefined.
4448: **
4449: ** ^The fourth parameter, eTextRep, specifies what
4450: ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
1.4 misho 4451: ** its parameters. The application should set this parameter to
4452: ** [SQLITE_UTF16LE] if the function implementation invokes
4453: ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
4454: ** implementation invokes [sqlite3_value_text16be()] on an input, or
4455: ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
4456: ** otherwise. ^The same SQL function may be registered multiple times using
4457: ** different preferred text encodings, with different implementations for
4458: ** each encoding.
1.2 misho 4459: ** ^When multiple implementations of the same function are available, SQLite
4460: ** will pick the one that involves the least amount of data conversion.
1.4 misho 4461: **
4462: ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
4463: ** to signal that the function will always return the same result given
4464: ** the same inputs within a single SQL statement. Most SQL functions are
4465: ** deterministic. The built-in [random()] SQL function is an example of a
4466: ** function that is not deterministic. The SQLite query planner is able to
4467: ** perform additional optimizations on deterministic functions, so use
4468: ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
1.2 misho 4469: **
4470: ** ^(The fifth parameter is an arbitrary pointer. The implementation of the
4471: ** function can gain access to this pointer using [sqlite3_user_data()].)^
4472: **
4473: ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
4474: ** pointers to C-language functions that implement the SQL function or
4475: ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
4476: ** callback only; NULL pointers must be passed as the xStep and xFinal
4477: ** parameters. ^An aggregate SQL function requires an implementation of xStep
4478: ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
4479: ** SQL function or aggregate, pass NULL pointers for all three function
4480: ** callbacks.
4481: **
4482: ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
4483: ** then it is destructor for the application data pointer.
4484: ** The destructor is invoked when the function is deleted, either by being
4485: ** overloaded or when the database connection closes.)^
4486: ** ^The destructor is also invoked if the call to
4487: ** sqlite3_create_function_v2() fails.
4488: ** ^When the destructor callback of the tenth parameter is invoked, it
4489: ** is passed a single argument which is a copy of the application data
4490: ** pointer which was the fifth parameter to sqlite3_create_function_v2().
4491: **
4492: ** ^It is permitted to register multiple implementations of the same
4493: ** functions with the same name but with either differing numbers of
4494: ** arguments or differing preferred text encodings. ^SQLite will use
4495: ** the implementation that most closely matches the way in which the
4496: ** SQL function is used. ^A function implementation with a non-negative
4497: ** nArg parameter is a better match than a function implementation with
4498: ** a negative nArg. ^A function where the preferred text encoding
4499: ** matches the database encoding is a better
4500: ** match than a function where the encoding is different.
4501: ** ^A function where the encoding difference is between UTF16le and UTF16be
4502: ** is a closer match than a function where the encoding difference is
4503: ** between UTF8 and UTF16.
4504: **
4505: ** ^Built-in functions may be overloaded by new application-defined functions.
4506: **
4507: ** ^An application-defined function is permitted to call other
4508: ** SQLite interfaces. However, such calls must not
4509: ** close the database connection nor finalize or reset the prepared
4510: ** statement in which the function is running.
4511: */
4512: SQLITE_API int sqlite3_create_function(
4513: sqlite3 *db,
4514: const char *zFunctionName,
4515: int nArg,
4516: int eTextRep,
4517: void *pApp,
4518: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4519: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4520: void (*xFinal)(sqlite3_context*)
4521: );
4522: SQLITE_API int sqlite3_create_function16(
4523: sqlite3 *db,
4524: const void *zFunctionName,
4525: int nArg,
4526: int eTextRep,
4527: void *pApp,
4528: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4529: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4530: void (*xFinal)(sqlite3_context*)
4531: );
4532: SQLITE_API int sqlite3_create_function_v2(
4533: sqlite3 *db,
4534: const char *zFunctionName,
4535: int nArg,
4536: int eTextRep,
4537: void *pApp,
4538: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4539: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4540: void (*xFinal)(sqlite3_context*),
4541: void(*xDestroy)(void*)
4542: );
4543:
4544: /*
4545: ** CAPI3REF: Text Encodings
4546: **
4547: ** These constant define integer codes that represent the various
4548: ** text encodings supported by SQLite.
4549: */
1.4 misho 4550: #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */
4551: #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */
4552: #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */
1.2 misho 4553: #define SQLITE_UTF16 4 /* Use native byte order */
1.4 misho 4554: #define SQLITE_ANY 5 /* Deprecated */
1.2 misho 4555: #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
4556:
4557: /*
1.4 misho 4558: ** CAPI3REF: Function Flags
4559: **
4560: ** These constants may be ORed together with the
4561: ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
4562: ** to [sqlite3_create_function()], [sqlite3_create_function16()], or
4563: ** [sqlite3_create_function_v2()].
4564: */
4565: #define SQLITE_DETERMINISTIC 0x800
4566:
4567: /*
1.2 misho 4568: ** CAPI3REF: Deprecated Functions
4569: ** DEPRECATED
4570: **
4571: ** These functions are [deprecated]. In order to maintain
4572: ** backwards compatibility with older code, these functions continue
4573: ** to be supported. However, new applications should avoid
1.4 misho 4574: ** the use of these functions. To encourage programmers to avoid
4575: ** these functions, we will not explain what they do.
1.2 misho 4576: */
4577: #ifndef SQLITE_OMIT_DEPRECATED
4578: SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
4579: SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
4580: SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
4581: SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
4582: SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
1.4 misho 4583: SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
4584: void*,sqlite3_int64);
1.2 misho 4585: #endif
4586:
4587: /*
1.4 misho 4588: ** CAPI3REF: Obtaining SQL Values
4589: ** METHOD: sqlite3_value
1.2 misho 4590: **
4591: ** The C-language implementation of SQL functions and aggregates uses
4592: ** this set of interface routines to access the parameter values on
1.4 misho 4593: ** the function or aggregate.
1.2 misho 4594: **
4595: ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
4596: ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
4597: ** define callbacks that implement the SQL functions and aggregates.
4598: ** The 3rd parameter to these callbacks is an array of pointers to
4599: ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
4600: ** each parameter to the SQL function. These routines are used to
4601: ** extract values from the [sqlite3_value] objects.
4602: **
4603: ** These routines work only with [protected sqlite3_value] objects.
4604: ** Any attempt to use these routines on an [unprotected sqlite3_value]
4605: ** object results in undefined behavior.
4606: **
4607: ** ^These routines work just like the corresponding [column access functions]
1.4 misho 4608: ** except that these routines take a single [protected sqlite3_value] object
1.2 misho 4609: ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
4610: **
4611: ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
4612: ** in the native byte-order of the host machine. ^The
4613: ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
4614: ** extract UTF-16 strings as big-endian and little-endian respectively.
4615: **
4616: ** ^(The sqlite3_value_numeric_type() interface attempts to apply
4617: ** numeric affinity to the value. This means that an attempt is
4618: ** made to convert the value to an integer or floating point. If
4619: ** such a conversion is possible without loss of information (in other
4620: ** words, if the value is a string that looks like a number)
4621: ** then the conversion is performed. Otherwise no conversion occurs.
4622: ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
4623: **
4624: ** Please pay particular attention to the fact that the pointer returned
4625: ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
4626: ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
4627: ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
4628: ** or [sqlite3_value_text16()].
4629: **
4630: ** These routines must be called from the same thread as
4631: ** the SQL function that supplied the [sqlite3_value*] parameters.
4632: */
4633: SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
4634: SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
4635: SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
4636: SQLITE_API double sqlite3_value_double(sqlite3_value*);
4637: SQLITE_API int sqlite3_value_int(sqlite3_value*);
4638: SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
4639: SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
4640: SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
4641: SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
4642: SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
4643: SQLITE_API int sqlite3_value_type(sqlite3_value*);
4644: SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
4645:
4646: /*
1.4 misho 4647: ** CAPI3REF: Finding The Subtype Of SQL Values
4648: ** METHOD: sqlite3_value
4649: **
4650: ** The sqlite3_value_subtype(V) function returns the subtype for
4651: ** an [application-defined SQL function] argument V. The subtype
4652: ** information can be used to pass a limited amount of context from
4653: ** one SQL function to another. Use the [sqlite3_result_subtype()]
4654: ** routine to set the subtype for the return value of an SQL function.
4655: **
4656: ** SQLite makes no use of subtype itself. It merely passes the subtype
4657: ** from the result of one [application-defined SQL function] into the
4658: ** input of another.
4659: */
4660: SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
4661:
4662: /*
4663: ** CAPI3REF: Copy And Free SQL Values
4664: ** METHOD: sqlite3_value
4665: **
4666: ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
4667: ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned
4668: ** is a [protected sqlite3_value] object even if the input is not.
4669: ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
4670: ** memory allocation fails.
4671: **
4672: ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
4673: ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer
4674: ** then sqlite3_value_free(V) is a harmless no-op.
4675: */
4676: SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
4677: SQLITE_API void sqlite3_value_free(sqlite3_value*);
4678:
4679: /*
1.2 misho 4680: ** CAPI3REF: Obtain Aggregate Function Context
1.4 misho 4681: ** METHOD: sqlite3_context
1.2 misho 4682: **
4683: ** Implementations of aggregate SQL functions use this
4684: ** routine to allocate memory for storing their state.
4685: **
4686: ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
4687: ** for a particular aggregate function, SQLite
4688: ** allocates N of memory, zeroes out that memory, and returns a pointer
4689: ** to the new memory. ^On second and subsequent calls to
4690: ** sqlite3_aggregate_context() for the same aggregate function instance,
4691: ** the same buffer is returned. Sqlite3_aggregate_context() is normally
4692: ** called once for each invocation of the xStep callback and then one
4693: ** last time when the xFinal callback is invoked. ^(When no rows match
4694: ** an aggregate query, the xStep() callback of the aggregate function
4695: ** implementation is never called and xFinal() is called exactly once.
4696: ** In those cases, sqlite3_aggregate_context() might be called for the
4697: ** first time from within xFinal().)^
4698: **
1.4 misho 4699: ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
4700: ** when first called if N is less than or equal to zero or if a memory
4701: ** allocate error occurs.
1.2 misho 4702: **
4703: ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
4704: ** determined by the N parameter on first successful call. Changing the
4705: ** value of N in subsequent call to sqlite3_aggregate_context() within
4706: ** the same aggregate function instance will not resize the memory
1.4 misho 4707: ** allocation.)^ Within the xFinal callback, it is customary to set
4708: ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
4709: ** pointless memory allocations occur.
1.2 misho 4710: **
4711: ** ^SQLite automatically frees the memory allocated by
4712: ** sqlite3_aggregate_context() when the aggregate query concludes.
4713: **
4714: ** The first parameter must be a copy of the
4715: ** [sqlite3_context | SQL function context] that is the first parameter
4716: ** to the xStep or xFinal callback routine that implements the aggregate
4717: ** function.
4718: **
4719: ** This routine must be called from the same thread in which
4720: ** the aggregate SQL function is running.
4721: */
4722: SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
4723:
4724: /*
4725: ** CAPI3REF: User Data For Functions
1.4 misho 4726: ** METHOD: sqlite3_context
1.2 misho 4727: **
4728: ** ^The sqlite3_user_data() interface returns a copy of
4729: ** the pointer that was the pUserData parameter (the 5th parameter)
4730: ** of the [sqlite3_create_function()]
4731: ** and [sqlite3_create_function16()] routines that originally
4732: ** registered the application defined function.
4733: **
4734: ** This routine must be called from the same thread in which
4735: ** the application-defined function is running.
4736: */
4737: SQLITE_API void *sqlite3_user_data(sqlite3_context*);
4738:
4739: /*
4740: ** CAPI3REF: Database Connection For Functions
1.4 misho 4741: ** METHOD: sqlite3_context
1.2 misho 4742: **
4743: ** ^The sqlite3_context_db_handle() interface returns a copy of
4744: ** the pointer to the [database connection] (the 1st parameter)
4745: ** of the [sqlite3_create_function()]
4746: ** and [sqlite3_create_function16()] routines that originally
4747: ** registered the application defined function.
4748: */
4749: SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
4750:
4751: /*
4752: ** CAPI3REF: Function Auxiliary Data
1.4 misho 4753: ** METHOD: sqlite3_context
1.2 misho 4754: **
1.4 misho 4755: ** These functions may be used by (non-aggregate) SQL functions to
1.2 misho 4756: ** associate metadata with argument values. If the same value is passed to
4757: ** multiple invocations of the same SQL function during query execution, under
1.4 misho 4758: ** some circumstances the associated metadata may be preserved. An example
4759: ** of where this might be useful is in a regular-expression matching
4760: ** function. The compiled version of the regular expression can be stored as
4761: ** metadata associated with the pattern string.
4762: ** Then as long as the pattern string remains the same,
4763: ** the compiled regular expression can be reused on multiple
4764: ** invocations of the same function.
1.2 misho 4765: **
1.4.2.1 ! misho 4766: ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
! 4767: ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
! 4768: ** value to the application-defined function. ^N is zero for the left-most
! 4769: ** function argument. ^If there is no metadata
! 4770: ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
1.4 misho 4771: ** returns a NULL pointer.
4772: **
4773: ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
4774: ** argument of the application-defined function. ^Subsequent
4775: ** calls to sqlite3_get_auxdata(C,N) return P from the most recent
4776: ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
4777: ** NULL if the metadata has been discarded.
4778: ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
4779: ** SQLite will invoke the destructor function X with parameter P exactly
4780: ** once, when the metadata is discarded.
4781: ** SQLite is free to discard the metadata at any time, including: <ul>
4782: ** <li> ^(when the corresponding function parameter changes)^, or
4783: ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
4784: ** SQL statement)^, or
4785: ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
4786: ** parameter)^, or
4787: ** <li> ^(during the original sqlite3_set_auxdata() call when a memory
4788: ** allocation error occurs.)^ </ul>
4789: **
4790: ** Note the last bullet in particular. The destructor X in
4791: ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
4792: ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
4793: ** should be called near the end of the function implementation and the
4794: ** function implementation should not make any use of P after
4795: ** sqlite3_set_auxdata() has been called.
1.2 misho 4796: **
4797: ** ^(In practice, metadata is preserved between function calls for
1.4 misho 4798: ** function parameters that are compile-time constants, including literal
4799: ** values and [parameters] and expressions composed from the same.)^
1.2 misho 4800: **
1.4.2.1 ! misho 4801: ** The value of the N parameter to these interfaces should be non-negative.
! 4802: ** Future enhancements may make use of negative N values to define new
! 4803: ** kinds of function caching behavior.
! 4804: **
1.2 misho 4805: ** These routines must be called from the same thread in which
4806: ** the SQL function is running.
4807: */
4808: SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
4809: SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
4810:
4811:
4812: /*
4813: ** CAPI3REF: Constants Defining Special Destructor Behavior
4814: **
4815: ** These are special values for the destructor that is passed in as the
4816: ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
4817: ** argument is SQLITE_STATIC, it means that the content pointer is constant
4818: ** and will never change. It does not need to be destroyed. ^The
4819: ** SQLITE_TRANSIENT value means that the content will likely change in
4820: ** the near future and that SQLite should make its own private copy of
4821: ** the content before returning.
4822: **
4823: ** The typedef is necessary to work around problems in certain
1.4 misho 4824: ** C++ compilers.
1.2 misho 4825: */
4826: typedef void (*sqlite3_destructor_type)(void*);
4827: #define SQLITE_STATIC ((sqlite3_destructor_type)0)
4828: #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
4829:
4830: /*
4831: ** CAPI3REF: Setting The Result Of An SQL Function
1.4 misho 4832: ** METHOD: sqlite3_context
1.2 misho 4833: **
4834: ** These routines are used by the xFunc or xFinal callbacks that
4835: ** implement SQL functions and aggregates. See
4836: ** [sqlite3_create_function()] and [sqlite3_create_function16()]
4837: ** for additional information.
4838: **
4839: ** These functions work very much like the [parameter binding] family of
4840: ** functions used to bind values to host parameters in prepared statements.
4841: ** Refer to the [SQL parameter] documentation for additional information.
4842: **
4843: ** ^The sqlite3_result_blob() interface sets the result from
4844: ** an application-defined function to be the BLOB whose content is pointed
4845: ** to by the second parameter and which is N bytes long where N is the
4846: ** third parameter.
4847: **
1.4 misho 4848: ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
4849: ** interfaces set the result of the application-defined function to be
4850: ** a BLOB containing all zero bytes and N bytes in size.
1.2 misho 4851: **
4852: ** ^The sqlite3_result_double() interface sets the result from
4853: ** an application-defined function to be a floating point value specified
4854: ** by its 2nd argument.
4855: **
4856: ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
4857: ** cause the implemented SQL function to throw an exception.
4858: ** ^SQLite uses the string pointed to by the
4859: ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
4860: ** as the text of an error message. ^SQLite interprets the error
4861: ** message string from sqlite3_result_error() as UTF-8. ^SQLite
4862: ** interprets the string from sqlite3_result_error16() as UTF-16 in native
4863: ** byte order. ^If the third parameter to sqlite3_result_error()
4864: ** or sqlite3_result_error16() is negative then SQLite takes as the error
4865: ** message all text up through the first zero character.
4866: ** ^If the third parameter to sqlite3_result_error() or
4867: ** sqlite3_result_error16() is non-negative then SQLite takes that many
4868: ** bytes (not characters) from the 2nd parameter as the error message.
4869: ** ^The sqlite3_result_error() and sqlite3_result_error16()
4870: ** routines make a private copy of the error message text before
4871: ** they return. Hence, the calling function can deallocate or
4872: ** modify the text after they return without harm.
4873: ** ^The sqlite3_result_error_code() function changes the error code
4874: ** returned by SQLite as a result of an error in a function. ^By default,
4875: ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
4876: ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
4877: **
1.3 misho 4878: ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
4879: ** error indicating that a string or BLOB is too long to represent.
1.2 misho 4880: **
1.3 misho 4881: ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
4882: ** error indicating that a memory allocation failed.
1.2 misho 4883: **
4884: ** ^The sqlite3_result_int() interface sets the return value
4885: ** of the application-defined function to be the 32-bit signed integer
4886: ** value given in the 2nd argument.
4887: ** ^The sqlite3_result_int64() interface sets the return value
4888: ** of the application-defined function to be the 64-bit signed integer
4889: ** value given in the 2nd argument.
4890: **
4891: ** ^The sqlite3_result_null() interface sets the return value
4892: ** of the application-defined function to be NULL.
4893: **
4894: ** ^The sqlite3_result_text(), sqlite3_result_text16(),
4895: ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
4896: ** set the return value of the application-defined function to be
4897: ** a text string which is represented as UTF-8, UTF-16 native byte order,
4898: ** UTF-16 little endian, or UTF-16 big endian, respectively.
1.4 misho 4899: ** ^The sqlite3_result_text64() interface sets the return value of an
4900: ** application-defined function to be a text string in an encoding
4901: ** specified by the fifth (and last) parameter, which must be one
4902: ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
1.2 misho 4903: ** ^SQLite takes the text result from the application from
4904: ** the 2nd parameter of the sqlite3_result_text* interfaces.
4905: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
4906: ** is negative, then SQLite takes result text from the 2nd parameter
4907: ** through the first zero character.
4908: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
4909: ** is non-negative, then as many bytes (not characters) of the text
4910: ** pointed to by the 2nd parameter are taken as the application-defined
4911: ** function result. If the 3rd parameter is non-negative, then it
4912: ** must be the byte offset into the string where the NUL terminator would
4913: ** appear if the string where NUL terminated. If any NUL characters occur
4914: ** in the string at a byte offset that is less than the value of the 3rd
4915: ** parameter, then the resulting string will contain embedded NULs and the
4916: ** result of expressions operating on strings with embedded NULs is undefined.
4917: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
4918: ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
4919: ** function as the destructor on the text or BLOB result when it has
4920: ** finished using that result.
4921: ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
4922: ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
4923: ** assumes that the text or BLOB result is in constant space and does not
4924: ** copy the content of the parameter nor call a destructor on the content
4925: ** when it has finished using that result.
4926: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
4927: ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
4928: ** then SQLite makes a copy of the result into space obtained from
4929: ** from [sqlite3_malloc()] before it returns.
4930: **
4931: ** ^The sqlite3_result_value() interface sets the result of
1.4 misho 4932: ** the application-defined function to be a copy of the
1.2 misho 4933: ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
4934: ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
4935: ** so that the [sqlite3_value] specified in the parameter may change or
4936: ** be deallocated after sqlite3_result_value() returns without harm.
4937: ** ^A [protected sqlite3_value] object may always be used where an
4938: ** [unprotected sqlite3_value] object is required, so either
4939: ** kind of [sqlite3_value] object can be used with this interface.
4940: **
4941: ** If these routines are called from within the different thread
4942: ** than the one containing the application-defined function that received
4943: ** the [sqlite3_context] pointer, the results are undefined.
4944: */
4945: SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
1.4 misho 4946: SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
4947: sqlite3_uint64,void(*)(void*));
1.2 misho 4948: SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
4949: SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
4950: SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
4951: SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
4952: SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
4953: SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
4954: SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
4955: SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
4956: SQLITE_API void sqlite3_result_null(sqlite3_context*);
4957: SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
1.4 misho 4958: SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
4959: void(*)(void*), unsigned char encoding);
1.2 misho 4960: SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
4961: SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
4962: SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
4963: SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
4964: SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
1.4 misho 4965: SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
4966:
4967:
4968: /*
4969: ** CAPI3REF: Setting The Subtype Of An SQL Function
4970: ** METHOD: sqlite3_context
4971: **
4972: ** The sqlite3_result_subtype(C,T) function causes the subtype of
4973: ** the result from the [application-defined SQL function] with
4974: ** [sqlite3_context] C to be the value T. Only the lower 8 bits
4975: ** of the subtype T are preserved in current versions of SQLite;
4976: ** higher order bits are discarded.
4977: ** The number of subtype bytes preserved by SQLite might increase
4978: ** in future releases of SQLite.
4979: */
4980: SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
1.2 misho 4981:
4982: /*
4983: ** CAPI3REF: Define New Collating Sequences
1.4 misho 4984: ** METHOD: sqlite3
1.2 misho 4985: **
4986: ** ^These functions add, remove, or modify a [collation] associated
4987: ** with the [database connection] specified as the first argument.
4988: **
4989: ** ^The name of the collation is a UTF-8 string
4990: ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
4991: ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
4992: ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
4993: ** considered to be the same name.
4994: **
4995: ** ^(The third argument (eTextRep) must be one of the constants:
4996: ** <ul>
4997: ** <li> [SQLITE_UTF8],
4998: ** <li> [SQLITE_UTF16LE],
4999: ** <li> [SQLITE_UTF16BE],
5000: ** <li> [SQLITE_UTF16], or
5001: ** <li> [SQLITE_UTF16_ALIGNED].
5002: ** </ul>)^
5003: ** ^The eTextRep argument determines the encoding of strings passed
5004: ** to the collating function callback, xCallback.
5005: ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
5006: ** force strings to be UTF16 with native byte order.
5007: ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
5008: ** on an even byte address.
5009: **
5010: ** ^The fourth argument, pArg, is an application data pointer that is passed
5011: ** through as the first argument to the collating function callback.
5012: **
5013: ** ^The fifth argument, xCallback, is a pointer to the collating function.
5014: ** ^Multiple collating functions can be registered using the same name but
5015: ** with different eTextRep parameters and SQLite will use whichever
5016: ** function requires the least amount of data transformation.
5017: ** ^If the xCallback argument is NULL then the collating function is
5018: ** deleted. ^When all collating functions having the same name are deleted,
5019: ** that collation is no longer usable.
5020: **
5021: ** ^The collating function callback is invoked with a copy of the pArg
5022: ** application data pointer and with two strings in the encoding specified
5023: ** by the eTextRep argument. The collating function must return an
5024: ** integer that is negative, zero, or positive
5025: ** if the first string is less than, equal to, or greater than the second,
5026: ** respectively. A collating function must always return the same answer
5027: ** given the same inputs. If two or more collating functions are registered
5028: ** to the same collation name (using different eTextRep values) then all
5029: ** must give an equivalent answer when invoked with equivalent strings.
5030: ** The collating function must obey the following properties for all
5031: ** strings A, B, and C:
5032: **
5033: ** <ol>
5034: ** <li> If A==B then B==A.
5035: ** <li> If A==B and B==C then A==C.
5036: ** <li> If A<B THEN B>A.
5037: ** <li> If A<B and B<C then A<C.
5038: ** </ol>
5039: **
5040: ** If a collating function fails any of the above constraints and that
5041: ** collating function is registered and used, then the behavior of SQLite
5042: ** is undefined.
5043: **
5044: ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
5045: ** with the addition that the xDestroy callback is invoked on pArg when
5046: ** the collating function is deleted.
5047: ** ^Collating functions are deleted when they are overridden by later
5048: ** calls to the collation creation functions or when the
5049: ** [database connection] is closed using [sqlite3_close()].
5050: **
5051: ** ^The xDestroy callback is <u>not</u> called if the
5052: ** sqlite3_create_collation_v2() function fails. Applications that invoke
5053: ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
5054: ** check the return code and dispose of the application data pointer
5055: ** themselves rather than expecting SQLite to deal with it for them.
5056: ** This is different from every other SQLite interface. The inconsistency
5057: ** is unfortunate but cannot be changed without breaking backwards
5058: ** compatibility.
5059: **
5060: ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
5061: */
5062: SQLITE_API int sqlite3_create_collation(
5063: sqlite3*,
5064: const char *zName,
5065: int eTextRep,
5066: void *pArg,
5067: int(*xCompare)(void*,int,const void*,int,const void*)
5068: );
5069: SQLITE_API int sqlite3_create_collation_v2(
5070: sqlite3*,
5071: const char *zName,
5072: int eTextRep,
5073: void *pArg,
5074: int(*xCompare)(void*,int,const void*,int,const void*),
5075: void(*xDestroy)(void*)
5076: );
5077: SQLITE_API int sqlite3_create_collation16(
5078: sqlite3*,
5079: const void *zName,
5080: int eTextRep,
5081: void *pArg,
5082: int(*xCompare)(void*,int,const void*,int,const void*)
5083: );
5084:
5085: /*
5086: ** CAPI3REF: Collation Needed Callbacks
1.4 misho 5087: ** METHOD: sqlite3
1.2 misho 5088: **
5089: ** ^To avoid having to register all collation sequences before a database
5090: ** can be used, a single callback function may be registered with the
5091: ** [database connection] to be invoked whenever an undefined collation
5092: ** sequence is required.
5093: **
5094: ** ^If the function is registered using the sqlite3_collation_needed() API,
5095: ** then it is passed the names of undefined collation sequences as strings
5096: ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
5097: ** the names are passed as UTF-16 in machine native byte order.
5098: ** ^A call to either function replaces the existing collation-needed callback.
5099: **
5100: ** ^(When the callback is invoked, the first argument passed is a copy
5101: ** of the second argument to sqlite3_collation_needed() or
5102: ** sqlite3_collation_needed16(). The second argument is the database
5103: ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
5104: ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
5105: ** sequence function required. The fourth parameter is the name of the
5106: ** required collation sequence.)^
5107: **
5108: ** The callback function should register the desired collation using
5109: ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
5110: ** [sqlite3_create_collation_v2()].
5111: */
5112: SQLITE_API int sqlite3_collation_needed(
5113: sqlite3*,
5114: void*,
5115: void(*)(void*,sqlite3*,int eTextRep,const char*)
5116: );
5117: SQLITE_API int sqlite3_collation_needed16(
5118: sqlite3*,
5119: void*,
5120: void(*)(void*,sqlite3*,int eTextRep,const void*)
5121: );
5122:
5123: #ifdef SQLITE_HAS_CODEC
5124: /*
5125: ** Specify the key for an encrypted database. This routine should be
5126: ** called right after sqlite3_open().
5127: **
5128: ** The code to implement this API is not available in the public release
5129: ** of SQLite.
5130: */
5131: SQLITE_API int sqlite3_key(
5132: sqlite3 *db, /* Database to be rekeyed */
5133: const void *pKey, int nKey /* The key */
5134: );
1.4 misho 5135: SQLITE_API int sqlite3_key_v2(
5136: sqlite3 *db, /* Database to be rekeyed */
5137: const char *zDbName, /* Name of the database */
5138: const void *pKey, int nKey /* The key */
5139: );
1.2 misho 5140:
5141: /*
5142: ** Change the key on an open database. If the current database is not
5143: ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
5144: ** database is decrypted.
5145: **
5146: ** The code to implement this API is not available in the public release
5147: ** of SQLite.
5148: */
5149: SQLITE_API int sqlite3_rekey(
5150: sqlite3 *db, /* Database to be rekeyed */
5151: const void *pKey, int nKey /* The new key */
5152: );
1.4 misho 5153: SQLITE_API int sqlite3_rekey_v2(
5154: sqlite3 *db, /* Database to be rekeyed */
5155: const char *zDbName, /* Name of the database */
5156: const void *pKey, int nKey /* The new key */
5157: );
1.2 misho 5158:
5159: /*
5160: ** Specify the activation key for a SEE database. Unless
5161: ** activated, none of the SEE routines will work.
5162: */
5163: SQLITE_API void sqlite3_activate_see(
5164: const char *zPassPhrase /* Activation phrase */
5165: );
5166: #endif
5167:
5168: #ifdef SQLITE_ENABLE_CEROD
5169: /*
5170: ** Specify the activation key for a CEROD database. Unless
5171: ** activated, none of the CEROD routines will work.
5172: */
5173: SQLITE_API void sqlite3_activate_cerod(
5174: const char *zPassPhrase /* Activation phrase */
5175: );
5176: #endif
5177:
5178: /*
5179: ** CAPI3REF: Suspend Execution For A Short Time
5180: **
5181: ** The sqlite3_sleep() function causes the current thread to suspend execution
5182: ** for at least a number of milliseconds specified in its parameter.
5183: **
5184: ** If the operating system does not support sleep requests with
5185: ** millisecond time resolution, then the time will be rounded up to
5186: ** the nearest second. The number of milliseconds of sleep actually
5187: ** requested from the operating system is returned.
5188: **
5189: ** ^SQLite implements this interface by calling the xSleep()
5190: ** method of the default [sqlite3_vfs] object. If the xSleep() method
5191: ** of the default VFS is not implemented correctly, or not implemented at
5192: ** all, then the behavior of sqlite3_sleep() may deviate from the description
5193: ** in the previous paragraphs.
5194: */
5195: SQLITE_API int sqlite3_sleep(int);
5196:
5197: /*
5198: ** CAPI3REF: Name Of The Folder Holding Temporary Files
5199: **
5200: ** ^(If this global variable is made to point to a string which is
5201: ** the name of a folder (a.k.a. directory), then all temporary files
5202: ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
5203: ** will be placed in that directory.)^ ^If this variable
5204: ** is a NULL pointer, then SQLite performs a search for an appropriate
5205: ** temporary file directory.
5206: **
1.4 misho 5207: ** Applications are strongly discouraged from using this global variable.
5208: ** It is required to set a temporary folder on Windows Runtime (WinRT).
5209: ** But for all other platforms, it is highly recommended that applications
5210: ** neither read nor write this variable. This global variable is a relic
5211: ** that exists for backwards compatibility of legacy applications and should
5212: ** be avoided in new projects.
5213: **
1.2 misho 5214: ** It is not safe to read or modify this variable in more than one
5215: ** thread at a time. It is not safe to read or modify this variable
5216: ** if a [database connection] is being used at the same time in a separate
5217: ** thread.
5218: ** It is intended that this variable be set once
5219: ** as part of process initialization and before any SQLite interface
5220: ** routines have been called and that this variable remain unchanged
5221: ** thereafter.
5222: **
5223: ** ^The [temp_store_directory pragma] may modify this variable and cause
5224: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
5225: ** the [temp_store_directory pragma] always assumes that any string
5226: ** that this variable points to is held in memory obtained from
5227: ** [sqlite3_malloc] and the pragma may attempt to free that memory
5228: ** using [sqlite3_free].
5229: ** Hence, if this variable is modified directly, either it should be
5230: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
5231: ** or else the use of the [temp_store_directory pragma] should be avoided.
1.4 misho 5232: ** Except when requested by the [temp_store_directory pragma], SQLite
5233: ** does not free the memory that sqlite3_temp_directory points to. If
5234: ** the application wants that memory to be freed, it must do
5235: ** so itself, taking care to only do so after all [database connection]
5236: ** objects have been destroyed.
1.3 misho 5237: **
5238: ** <b>Note to Windows Runtime users:</b> The temporary directory must be set
5239: ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
5240: ** features that require the use of temporary files may fail. Here is an
5241: ** example of how to do this using C++ with the Windows Runtime:
5242: **
5243: ** <blockquote><pre>
5244: ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
5245: ** TemporaryFolder->Path->Data();
5246: ** char zPathBuf[MAX_PATH + 1];
5247: ** memset(zPathBuf, 0, sizeof(zPathBuf));
5248: ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
5249: ** NULL, NULL);
5250: ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
5251: ** </pre></blockquote>
1.2 misho 5252: */
5253: SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
5254:
5255: /*
1.3 misho 5256: ** CAPI3REF: Name Of The Folder Holding Database Files
5257: **
5258: ** ^(If this global variable is made to point to a string which is
5259: ** the name of a folder (a.k.a. directory), then all database files
5260: ** specified with a relative pathname and created or accessed by
5261: ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
5262: ** to be relative to that directory.)^ ^If this variable is a NULL
5263: ** pointer, then SQLite assumes that all database files specified
5264: ** with a relative pathname are relative to the current directory
5265: ** for the process. Only the windows VFS makes use of this global
5266: ** variable; it is ignored by the unix VFS.
5267: **
5268: ** Changing the value of this variable while a database connection is
5269: ** open can result in a corrupt database.
5270: **
5271: ** It is not safe to read or modify this variable in more than one
5272: ** thread at a time. It is not safe to read or modify this variable
5273: ** if a [database connection] is being used at the same time in a separate
5274: ** thread.
5275: ** It is intended that this variable be set once
5276: ** as part of process initialization and before any SQLite interface
5277: ** routines have been called and that this variable remain unchanged
5278: ** thereafter.
5279: **
5280: ** ^The [data_store_directory pragma] may modify this variable and cause
5281: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
5282: ** the [data_store_directory pragma] always assumes that any string
5283: ** that this variable points to is held in memory obtained from
5284: ** [sqlite3_malloc] and the pragma may attempt to free that memory
5285: ** using [sqlite3_free].
5286: ** Hence, if this variable is modified directly, either it should be
5287: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
5288: ** or else the use of the [data_store_directory pragma] should be avoided.
5289: */
5290: SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
5291:
5292: /*
1.2 misho 5293: ** CAPI3REF: Test For Auto-Commit Mode
5294: ** KEYWORDS: {autocommit mode}
1.4 misho 5295: ** METHOD: sqlite3
1.2 misho 5296: **
5297: ** ^The sqlite3_get_autocommit() interface returns non-zero or
5298: ** zero if the given database connection is or is not in autocommit mode,
5299: ** respectively. ^Autocommit mode is on by default.
5300: ** ^Autocommit mode is disabled by a [BEGIN] statement.
5301: ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
5302: **
5303: ** If certain kinds of errors occur on a statement within a multi-statement
5304: ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
5305: ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
5306: ** transaction might be rolled back automatically. The only way to
5307: ** find out whether SQLite automatically rolled back the transaction after
5308: ** an error is to use this function.
5309: **
5310: ** If another thread changes the autocommit status of the database
5311: ** connection while this routine is running, then the return value
5312: ** is undefined.
5313: */
5314: SQLITE_API int sqlite3_get_autocommit(sqlite3*);
5315:
5316: /*
5317: ** CAPI3REF: Find The Database Handle Of A Prepared Statement
1.4 misho 5318: ** METHOD: sqlite3_stmt
1.2 misho 5319: **
5320: ** ^The sqlite3_db_handle interface returns the [database connection] handle
5321: ** to which a [prepared statement] belongs. ^The [database connection]
5322: ** returned by sqlite3_db_handle is the same [database connection]
5323: ** that was the first argument
5324: ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
5325: ** create the statement in the first place.
5326: */
5327: SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
5328:
5329: /*
5330: ** CAPI3REF: Return The Filename For A Database Connection
1.4 misho 5331: ** METHOD: sqlite3
1.2 misho 5332: **
5333: ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
5334: ** associated with database N of connection D. ^The main database file
5335: ** has the name "main". If there is no attached database N on the database
5336: ** connection D, or if database N is a temporary or in-memory database, then
5337: ** a NULL pointer is returned.
5338: **
5339: ** ^The filename returned by this function is the output of the
5340: ** xFullPathname method of the [VFS]. ^In other words, the filename
5341: ** will be an absolute pathname, even if the filename used
5342: ** to open the database originally was a URI or relative pathname.
5343: */
5344: SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
5345:
5346: /*
1.3 misho 5347: ** CAPI3REF: Determine if a database is read-only
1.4 misho 5348: ** METHOD: sqlite3
1.3 misho 5349: **
5350: ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
5351: ** of connection D is read-only, 0 if it is read/write, or -1 if N is not
5352: ** the name of a database on connection D.
5353: */
5354: SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
5355:
5356: /*
1.2 misho 5357: ** CAPI3REF: Find the next prepared statement
1.4 misho 5358: ** METHOD: sqlite3
1.2 misho 5359: **
5360: ** ^This interface returns a pointer to the next [prepared statement] after
5361: ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
5362: ** then this interface returns a pointer to the first prepared statement
5363: ** associated with the database connection pDb. ^If no prepared statement
5364: ** satisfies the conditions of this routine, it returns NULL.
5365: **
5366: ** The [database connection] pointer D in a call to
5367: ** [sqlite3_next_stmt(D,S)] must refer to an open database
5368: ** connection and in particular must not be a NULL pointer.
5369: */
5370: SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
5371:
5372: /*
5373: ** CAPI3REF: Commit And Rollback Notification Callbacks
1.4 misho 5374: ** METHOD: sqlite3
1.2 misho 5375: **
5376: ** ^The sqlite3_commit_hook() interface registers a callback
5377: ** function to be invoked whenever a transaction is [COMMIT | committed].
5378: ** ^Any callback set by a previous call to sqlite3_commit_hook()
5379: ** for the same database connection is overridden.
5380: ** ^The sqlite3_rollback_hook() interface registers a callback
5381: ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
5382: ** ^Any callback set by a previous call to sqlite3_rollback_hook()
5383: ** for the same database connection is overridden.
5384: ** ^The pArg argument is passed through to the callback.
5385: ** ^If the callback on a commit hook function returns non-zero,
5386: ** then the commit is converted into a rollback.
5387: **
5388: ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
5389: ** return the P argument from the previous call of the same function
5390: ** on the same [database connection] D, or NULL for
5391: ** the first call for each function on D.
5392: **
5393: ** The commit and rollback hook callbacks are not reentrant.
5394: ** The callback implementation must not do anything that will modify
5395: ** the database connection that invoked the callback. Any actions
5396: ** to modify the database connection must be deferred until after the
5397: ** completion of the [sqlite3_step()] call that triggered the commit
5398: ** or rollback hook in the first place.
5399: ** Note that running any other SQL statements, including SELECT statements,
5400: ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
5401: ** the database connections for the meaning of "modify" in this paragraph.
5402: **
5403: ** ^Registering a NULL function disables the callback.
5404: **
5405: ** ^When the commit hook callback routine returns zero, the [COMMIT]
5406: ** operation is allowed to continue normally. ^If the commit hook
5407: ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
5408: ** ^The rollback hook is invoked on a rollback that results from a commit
5409: ** hook returning non-zero, just as it would be with any other rollback.
5410: **
5411: ** ^For the purposes of this API, a transaction is said to have been
5412: ** rolled back if an explicit "ROLLBACK" statement is executed, or
5413: ** an error or constraint causes an implicit rollback to occur.
5414: ** ^The rollback callback is not invoked if a transaction is
5415: ** automatically rolled back because the database connection is closed.
5416: **
5417: ** See also the [sqlite3_update_hook()] interface.
5418: */
5419: SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
5420: SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
5421:
5422: /*
5423: ** CAPI3REF: Data Change Notification Callbacks
1.4 misho 5424: ** METHOD: sqlite3
1.2 misho 5425: **
5426: ** ^The sqlite3_update_hook() interface registers a callback function
5427: ** with the [database connection] identified by the first argument
1.4 misho 5428: ** to be invoked whenever a row is updated, inserted or deleted in
5429: ** a [rowid table].
1.2 misho 5430: ** ^Any callback set by a previous call to this function
5431: ** for the same database connection is overridden.
5432: **
5433: ** ^The second argument is a pointer to the function to invoke when a
1.4 misho 5434: ** row is updated, inserted or deleted in a rowid table.
1.2 misho 5435: ** ^The first argument to the callback is a copy of the third argument
5436: ** to sqlite3_update_hook().
5437: ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
5438: ** or [SQLITE_UPDATE], depending on the operation that caused the callback
5439: ** to be invoked.
5440: ** ^The third and fourth arguments to the callback contain pointers to the
5441: ** database and table name containing the affected row.
5442: ** ^The final callback parameter is the [rowid] of the row.
5443: ** ^In the case of an update, this is the [rowid] after the update takes place.
5444: **
5445: ** ^(The update hook is not invoked when internal system tables are
5446: ** modified (i.e. sqlite_master and sqlite_sequence).)^
1.4 misho 5447: ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
1.2 misho 5448: **
5449: ** ^In the current implementation, the update hook
1.4.2.1 ! misho 5450: ** is not invoked when conflicting rows are deleted because of an
1.2 misho 5451: ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
5452: ** invoked when rows are deleted using the [truncate optimization].
5453: ** The exceptions defined in this paragraph might change in a future
5454: ** release of SQLite.
5455: **
5456: ** The update hook implementation must not do anything that will modify
5457: ** the database connection that invoked the update hook. Any actions
5458: ** to modify the database connection must be deferred until after the
5459: ** completion of the [sqlite3_step()] call that triggered the update hook.
5460: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
5461: ** database connections for the meaning of "modify" in this paragraph.
5462: **
5463: ** ^The sqlite3_update_hook(D,C,P) function
5464: ** returns the P argument from the previous call
5465: ** on the same [database connection] D, or NULL for
5466: ** the first call on D.
5467: **
1.4 misho 5468: ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
5469: ** and [sqlite3_preupdate_hook()] interfaces.
1.2 misho 5470: */
5471: SQLITE_API void *sqlite3_update_hook(
5472: sqlite3*,
5473: void(*)(void *,int ,char const *,char const *,sqlite3_int64),
5474: void*
5475: );
5476:
5477: /*
5478: ** CAPI3REF: Enable Or Disable Shared Pager Cache
5479: **
5480: ** ^(This routine enables or disables the sharing of the database cache
5481: ** and schema data structures between [database connection | connections]
5482: ** to the same database. Sharing is enabled if the argument is true
5483: ** and disabled if the argument is false.)^
5484: **
5485: ** ^Cache sharing is enabled and disabled for an entire process.
1.4.2.1 ! misho 5486: ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
! 5487: ** In prior versions of SQLite,
1.2 misho 5488: ** sharing was enabled or disabled for each thread separately.
5489: **
5490: ** ^(The cache sharing mode set by this interface effects all subsequent
5491: ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
5492: ** Existing database connections continue use the sharing mode
5493: ** that was in effect at the time they were opened.)^
5494: **
5495: ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
5496: ** successfully. An [error code] is returned otherwise.)^
5497: **
5498: ** ^Shared cache is disabled by default. But this might change in
5499: ** future releases of SQLite. Applications that care about shared
5500: ** cache setting should set it explicitly.
5501: **
1.4 misho 5502: ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
5503: ** and will always return SQLITE_MISUSE. On those systems,
5504: ** shared cache mode should be enabled per-database connection via
5505: ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
5506: **
1.3 misho 5507: ** This interface is threadsafe on processors where writing a
5508: ** 32-bit integer is atomic.
5509: **
1.2 misho 5510: ** See Also: [SQLite Shared-Cache Mode]
5511: */
5512: SQLITE_API int sqlite3_enable_shared_cache(int);
5513:
5514: /*
5515: ** CAPI3REF: Attempt To Free Heap Memory
5516: **
5517: ** ^The sqlite3_release_memory() interface attempts to free N bytes
5518: ** of heap memory by deallocating non-essential memory allocations
5519: ** held by the database library. Memory used to cache database
5520: ** pages to improve performance is an example of non-essential memory.
5521: ** ^sqlite3_release_memory() returns the number of bytes actually freed,
5522: ** which might be more or less than the amount requested.
5523: ** ^The sqlite3_release_memory() routine is a no-op returning zero
5524: ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
5525: **
5526: ** See also: [sqlite3_db_release_memory()]
5527: */
5528: SQLITE_API int sqlite3_release_memory(int);
5529:
5530: /*
5531: ** CAPI3REF: Free Memory Used By A Database Connection
1.4 misho 5532: ** METHOD: sqlite3
1.2 misho 5533: **
5534: ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
5535: ** memory as possible from database connection D. Unlike the
1.4 misho 5536: ** [sqlite3_release_memory()] interface, this interface is in effect even
5537: ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
1.2 misho 5538: ** omitted.
5539: **
5540: ** See also: [sqlite3_release_memory()]
5541: */
5542: SQLITE_API int sqlite3_db_release_memory(sqlite3*);
5543:
5544: /*
5545: ** CAPI3REF: Impose A Limit On Heap Size
5546: **
5547: ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
5548: ** soft limit on the amount of heap memory that may be allocated by SQLite.
5549: ** ^SQLite strives to keep heap memory utilization below the soft heap
5550: ** limit by reducing the number of pages held in the page cache
5551: ** as heap memory usages approaches the limit.
5552: ** ^The soft heap limit is "soft" because even though SQLite strives to stay
5553: ** below the limit, it will exceed the limit rather than generate
5554: ** an [SQLITE_NOMEM] error. In other words, the soft heap limit
5555: ** is advisory only.
5556: **
5557: ** ^The return value from sqlite3_soft_heap_limit64() is the size of
5558: ** the soft heap limit prior to the call, or negative in the case of an
5559: ** error. ^If the argument N is negative
5560: ** then no change is made to the soft heap limit. Hence, the current
5561: ** size of the soft heap limit can be determined by invoking
5562: ** sqlite3_soft_heap_limit64() with a negative argument.
5563: **
5564: ** ^If the argument N is zero then the soft heap limit is disabled.
5565: **
5566: ** ^(The soft heap limit is not enforced in the current implementation
5567: ** if one or more of following conditions are true:
5568: **
5569: ** <ul>
5570: ** <li> The soft heap limit is set to zero.
5571: ** <li> Memory accounting is disabled using a combination of the
5572: ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
5573: ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
5574: ** <li> An alternative page cache implementation is specified using
5575: ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
5576: ** <li> The page cache allocates from its own memory pool supplied
5577: ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
5578: ** from the heap.
5579: ** </ul>)^
5580: **
1.4.2.1 ! misho 5581: ** Beginning with SQLite [version 3.7.3] ([dateof:3.7.3]),
! 5582: ** the soft heap limit is enforced
1.2 misho 5583: ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
5584: ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
5585: ** the soft heap limit is enforced on every memory allocation. Without
5586: ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
5587: ** when memory is allocated by the page cache. Testing suggests that because
5588: ** the page cache is the predominate memory user in SQLite, most
5589: ** applications will achieve adequate soft heap limit enforcement without
5590: ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
5591: **
5592: ** The circumstances under which SQLite will enforce the soft heap limit may
5593: ** changes in future releases of SQLite.
5594: */
5595: SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
5596:
5597: /*
5598: ** CAPI3REF: Deprecated Soft Heap Limit Interface
5599: ** DEPRECATED
5600: **
5601: ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
5602: ** interface. This routine is provided for historical compatibility
5603: ** only. All new applications should use the
5604: ** [sqlite3_soft_heap_limit64()] interface rather than this one.
5605: */
5606: SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
5607:
5608:
5609: /*
5610: ** CAPI3REF: Extract Metadata About A Column Of A Table
1.4 misho 5611: ** METHOD: sqlite3
1.2 misho 5612: **
1.4 misho 5613: ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
5614: ** information about column C of table T in database D
5615: ** on [database connection] X.)^ ^The sqlite3_table_column_metadata()
5616: ** interface returns SQLITE_OK and fills in the non-NULL pointers in
5617: ** the final five arguments with appropriate values if the specified
5618: ** column exists. ^The sqlite3_table_column_metadata() interface returns
5619: ** SQLITE_ERROR and if the specified column does not exist.
5620: ** ^If the column-name parameter to sqlite3_table_column_metadata() is a
5621: ** NULL pointer, then this routine simply checks for the existence of the
5622: ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
5623: ** does not.
1.2 misho 5624: **
5625: ** ^The column is identified by the second, third and fourth parameters to
1.4 misho 5626: ** this function. ^(The second parameter is either the name of the database
1.2 misho 5627: ** (i.e. "main", "temp", or an attached database) containing the specified
1.4 misho 5628: ** table or NULL.)^ ^If it is NULL, then all attached databases are searched
1.2 misho 5629: ** for the table using the same algorithm used by the database engine to
5630: ** resolve unqualified table references.
5631: **
5632: ** ^The third and fourth parameters to this function are the table and column
1.4 misho 5633: ** name of the desired column, respectively.
1.2 misho 5634: **
5635: ** ^Metadata is returned by writing to the memory locations passed as the 5th
5636: ** and subsequent parameters to this function. ^Any of these arguments may be
5637: ** NULL, in which case the corresponding element of metadata is omitted.
5638: **
5639: ** ^(<blockquote>
5640: ** <table border="1">
5641: ** <tr><th> Parameter <th> Output<br>Type <th> Description
5642: **
5643: ** <tr><td> 5th <td> const char* <td> Data type
5644: ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
5645: ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
5646: ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
5647: ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
5648: ** </table>
5649: ** </blockquote>)^
5650: **
5651: ** ^The memory pointed to by the character pointers returned for the
1.4 misho 5652: ** declaration type and collation sequence is valid until the next
1.2 misho 5653: ** call to any SQLite API function.
5654: **
5655: ** ^If the specified table is actually a view, an [error code] is returned.
5656: **
1.4 misho 5657: ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
5658: ** is not a [WITHOUT ROWID] table and an
1.2 misho 5659: ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
5660: ** parameters are set for the explicitly declared column. ^(If there is no
1.4 misho 5661: ** [INTEGER PRIMARY KEY] column, then the outputs
5662: ** for the [rowid] are set as follows:
1.2 misho 5663: **
5664: ** <pre>
5665: ** data type: "INTEGER"
5666: ** collation sequence: "BINARY"
5667: ** not null: 0
5668: ** primary key: 1
5669: ** auto increment: 0
5670: ** </pre>)^
5671: **
1.4 misho 5672: ** ^This function causes all database schemas to be read from disk and
5673: ** parsed, if that has not already been done, and returns an error if
5674: ** any errors are encountered while loading the schema.
1.2 misho 5675: */
5676: SQLITE_API int sqlite3_table_column_metadata(
5677: sqlite3 *db, /* Connection handle */
5678: const char *zDbName, /* Database name or NULL */
5679: const char *zTableName, /* Table name */
5680: const char *zColumnName, /* Column name */
5681: char const **pzDataType, /* OUTPUT: Declared data type */
5682: char const **pzCollSeq, /* OUTPUT: Collation sequence name */
5683: int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
5684: int *pPrimaryKey, /* OUTPUT: True if column part of PK */
5685: int *pAutoinc /* OUTPUT: True if column is auto-increment */
5686: );
5687:
5688: /*
5689: ** CAPI3REF: Load An Extension
1.4 misho 5690: ** METHOD: sqlite3
1.2 misho 5691: **
5692: ** ^This interface loads an SQLite extension library from the named file.
5693: **
5694: ** ^The sqlite3_load_extension() interface attempts to load an
1.4 misho 5695: ** [SQLite extension] library contained in the file zFile. If
5696: ** the file cannot be loaded directly, attempts are made to load
5697: ** with various operating-system specific extensions added.
5698: ** So for example, if "samplelib" cannot be loaded, then names like
5699: ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
5700: ** be tried also.
1.2 misho 5701: **
5702: ** ^The entry point is zProc.
1.4 misho 5703: ** ^(zProc may be 0, in which case SQLite will try to come up with an
5704: ** entry point name on its own. It first tries "sqlite3_extension_init".
5705: ** If that does not work, it constructs a name "sqlite3_X_init" where the
5706: ** X is consists of the lower-case equivalent of all ASCII alphabetic
5707: ** characters in the filename from the last "/" to the first following
5708: ** "." and omitting any initial "lib".)^
1.2 misho 5709: ** ^The sqlite3_load_extension() interface returns
5710: ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
5711: ** ^If an error occurs and pzErrMsg is not 0, then the
5712: ** [sqlite3_load_extension()] interface shall attempt to
5713: ** fill *pzErrMsg with error message text stored in memory
5714: ** obtained from [sqlite3_malloc()]. The calling function
5715: ** should free this memory by calling [sqlite3_free()].
5716: **
5717: ** ^Extension loading must be enabled using
1.4 misho 5718: ** [sqlite3_enable_load_extension()] or
5719: ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
5720: ** prior to calling this API,
1.2 misho 5721: ** otherwise an error will be returned.
5722: **
1.4 misho 5723: ** <b>Security warning:</b> It is recommended that the
5724: ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
5725: ** interface. The use of the [sqlite3_enable_load_extension()] interface
5726: ** should be avoided. This will keep the SQL function [load_extension()]
5727: ** disabled and prevent SQL injections from giving attackers
5728: ** access to extension loading capabilities.
5729: **
1.2 misho 5730: ** See also the [load_extension() SQL function].
5731: */
5732: SQLITE_API int sqlite3_load_extension(
5733: sqlite3 *db, /* Load the extension into this database connection */
5734: const char *zFile, /* Name of the shared library containing extension */
5735: const char *zProc, /* Entry point. Derived from zFile if 0 */
5736: char **pzErrMsg /* Put error message here if not 0 */
5737: );
5738:
5739: /*
5740: ** CAPI3REF: Enable Or Disable Extension Loading
1.4 misho 5741: ** METHOD: sqlite3
1.2 misho 5742: **
5743: ** ^So as not to open security holes in older applications that are
1.4 misho 5744: ** unprepared to deal with [extension loading], and as a means of disabling
5745: ** [extension loading] while evaluating user-entered SQL, the following API
1.2 misho 5746: ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
5747: **
1.4 misho 5748: ** ^Extension loading is off by default.
1.2 misho 5749: ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
5750: ** to turn extension loading on and call it with onoff==0 to turn
5751: ** it back off again.
1.4 misho 5752: **
5753: ** ^This interface enables or disables both the C-API
5754: ** [sqlite3_load_extension()] and the SQL function [load_extension()].
5755: ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
5756: ** to enable or disable only the C-API.)^
5757: **
5758: ** <b>Security warning:</b> It is recommended that extension loading
5759: ** be disabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
5760: ** rather than this interface, so the [load_extension()] SQL function
5761: ** remains disabled. This will prevent SQL injections from giving attackers
5762: ** access to extension loading capabilities.
1.2 misho 5763: */
5764: SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
5765:
5766: /*
5767: ** CAPI3REF: Automatically Load Statically Linked Extensions
5768: **
5769: ** ^This interface causes the xEntryPoint() function to be invoked for
5770: ** each new [database connection] that is created. The idea here is that
1.4 misho 5771: ** xEntryPoint() is the entry point for a statically linked [SQLite extension]
1.2 misho 5772: ** that is to be automatically loaded into all new database connections.
5773: **
5774: ** ^(Even though the function prototype shows that xEntryPoint() takes
5775: ** no arguments and returns void, SQLite invokes xEntryPoint() with three
1.4 misho 5776: ** arguments and expects an integer result as if the signature of the
1.2 misho 5777: ** entry point where as follows:
5778: **
5779: ** <blockquote><pre>
5780: ** int xEntryPoint(
5781: ** sqlite3 *db,
5782: ** const char **pzErrMsg,
5783: ** const struct sqlite3_api_routines *pThunk
5784: ** );
5785: ** </pre></blockquote>)^
5786: **
5787: ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
5788: ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
5789: ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
5790: ** is NULL before calling the xEntryPoint(). ^SQLite will invoke
5791: ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
5792: ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
5793: ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
5794: **
5795: ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
5796: ** on the list of automatic extensions is a harmless no-op. ^No entry point
5797: ** will be called more than once for each database connection that is opened.
5798: **
1.4 misho 5799: ** See also: [sqlite3_reset_auto_extension()]
5800: ** and [sqlite3_cancel_auto_extension()]
1.2 misho 5801: */
1.4 misho 5802: SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
5803:
5804: /*
5805: ** CAPI3REF: Cancel Automatic Extension Loading
5806: **
5807: ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
5808: ** initialization routine X that was registered using a prior call to
5809: ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
5810: ** routine returns 1 if initialization routine X was successfully
5811: ** unregistered and it returns 0 if X was not on the list of initialization
5812: ** routines.
5813: */
5814: SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
1.2 misho 5815:
5816: /*
5817: ** CAPI3REF: Reset Automatic Extension Loading
5818: **
5819: ** ^This interface disables all automatic extensions previously
5820: ** registered using [sqlite3_auto_extension()].
5821: */
5822: SQLITE_API void sqlite3_reset_auto_extension(void);
5823:
5824: /*
5825: ** The interface to the virtual-table mechanism is currently considered
5826: ** to be experimental. The interface might change in incompatible ways.
5827: ** If this is a problem for you, do not use the interface at this time.
5828: **
5829: ** When the virtual-table mechanism stabilizes, we will declare the
5830: ** interface fixed, support it indefinitely, and remove this comment.
5831: */
5832:
5833: /*
5834: ** Structures used by the virtual table interface
5835: */
5836: typedef struct sqlite3_vtab sqlite3_vtab;
5837: typedef struct sqlite3_index_info sqlite3_index_info;
5838: typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
5839: typedef struct sqlite3_module sqlite3_module;
5840:
5841: /*
5842: ** CAPI3REF: Virtual Table Object
5843: ** KEYWORDS: sqlite3_module {virtual table module}
5844: **
5845: ** This structure, sometimes called a "virtual table module",
5846: ** defines the implementation of a [virtual tables].
5847: ** This structure consists mostly of methods for the module.
5848: **
5849: ** ^A virtual table module is created by filling in a persistent
5850: ** instance of this structure and passing a pointer to that instance
5851: ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
5852: ** ^The registration remains valid until it is replaced by a different
5853: ** module or until the [database connection] closes. The content
5854: ** of this structure must not change while it is registered with
5855: ** any database connection.
5856: */
5857: struct sqlite3_module {
5858: int iVersion;
5859: int (*xCreate)(sqlite3*, void *pAux,
5860: int argc, const char *const*argv,
5861: sqlite3_vtab **ppVTab, char**);
5862: int (*xConnect)(sqlite3*, void *pAux,
5863: int argc, const char *const*argv,
5864: sqlite3_vtab **ppVTab, char**);
5865: int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
5866: int (*xDisconnect)(sqlite3_vtab *pVTab);
5867: int (*xDestroy)(sqlite3_vtab *pVTab);
5868: int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
5869: int (*xClose)(sqlite3_vtab_cursor*);
5870: int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
5871: int argc, sqlite3_value **argv);
5872: int (*xNext)(sqlite3_vtab_cursor*);
5873: int (*xEof)(sqlite3_vtab_cursor*);
5874: int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
5875: int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
5876: int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
5877: int (*xBegin)(sqlite3_vtab *pVTab);
5878: int (*xSync)(sqlite3_vtab *pVTab);
5879: int (*xCommit)(sqlite3_vtab *pVTab);
5880: int (*xRollback)(sqlite3_vtab *pVTab);
5881: int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
5882: void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
5883: void **ppArg);
5884: int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
5885: /* The methods above are in version 1 of the sqlite_module object. Those
5886: ** below are for version 2 and greater. */
5887: int (*xSavepoint)(sqlite3_vtab *pVTab, int);
5888: int (*xRelease)(sqlite3_vtab *pVTab, int);
5889: int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
5890: };
5891:
5892: /*
5893: ** CAPI3REF: Virtual Table Indexing Information
5894: ** KEYWORDS: sqlite3_index_info
5895: **
5896: ** The sqlite3_index_info structure and its substructures is used as part
5897: ** of the [virtual table] interface to
5898: ** pass information into and receive the reply from the [xBestIndex]
5899: ** method of a [virtual table module]. The fields under **Inputs** are the
5900: ** inputs to xBestIndex and are read-only. xBestIndex inserts its
5901: ** results into the **Outputs** fields.
5902: **
5903: ** ^(The aConstraint[] array records WHERE clause constraints of the form:
5904: **
5905: ** <blockquote>column OP expr</blockquote>
5906: **
5907: ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
5908: ** stored in aConstraint[].op using one of the
5909: ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
5910: ** ^(The index of the column is stored in
5911: ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
5912: ** expr on the right-hand side can be evaluated (and thus the constraint
5913: ** is usable) and false if it cannot.)^
5914: **
5915: ** ^The optimizer automatically inverts terms of the form "expr OP column"
5916: ** and makes other simplifications to the WHERE clause in an attempt to
5917: ** get as many WHERE clause terms into the form shown above as possible.
5918: ** ^The aConstraint[] array only reports WHERE clause terms that are
5919: ** relevant to the particular virtual table being queried.
5920: **
5921: ** ^Information about the ORDER BY clause is stored in aOrderBy[].
5922: ** ^Each term of aOrderBy records a column of the ORDER BY clause.
5923: **
1.4 misho 5924: ** The colUsed field indicates which columns of the virtual table may be
5925: ** required by the current scan. Virtual table columns are numbered from
5926: ** zero in the order in which they appear within the CREATE TABLE statement
5927: ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
5928: ** the corresponding bit is set within the colUsed mask if the column may be
5929: ** required by SQLite. If the table has at least 64 columns and any column
5930: ** to the right of the first 63 is required, then bit 63 of colUsed is also
5931: ** set. In other words, column iCol may be required if the expression
5932: ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
5933: ** non-zero.
5934: **
1.2 misho 5935: ** The [xBestIndex] method must fill aConstraintUsage[] with information
5936: ** about what parameters to pass to xFilter. ^If argvIndex>0 then
5937: ** the right-hand side of the corresponding aConstraint[] is evaluated
5938: ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
5939: ** is true, then the constraint is assumed to be fully handled by the
5940: ** virtual table and is not checked again by SQLite.)^
5941: **
5942: ** ^The idxNum and idxPtr values are recorded and passed into the
5943: ** [xFilter] method.
5944: ** ^[sqlite3_free()] is used to free idxPtr if and only if
5945: ** needToFreeIdxPtr is true.
5946: **
5947: ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
5948: ** the correct order to satisfy the ORDER BY clause so that no separate
5949: ** sorting step is required.
5950: **
1.4 misho 5951: ** ^The estimatedCost value is an estimate of the cost of a particular
5952: ** strategy. A cost of N indicates that the cost of the strategy is similar
5953: ** to a linear scan of an SQLite table with N rows. A cost of log(N)
5954: ** indicates that the expense of the operation is similar to that of a
5955: ** binary search on a unique indexed field of an SQLite table with N rows.
5956: **
5957: ** ^The estimatedRows value is an estimate of the number of rows that
5958: ** will be returned by the strategy.
5959: **
5960: ** The xBestIndex method may optionally populate the idxFlags field with a
5961: ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
5962: ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
5963: ** assumes that the strategy may visit at most one row.
5964: **
5965: ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
5966: ** SQLite also assumes that if a call to the xUpdate() method is made as
5967: ** part of the same statement to delete or update a virtual table row and the
5968: ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
5969: ** any database changes. In other words, if the xUpdate() returns
5970: ** SQLITE_CONSTRAINT, the database contents must be exactly as they were
5971: ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
5972: ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
5973: ** the xUpdate method are automatically rolled back by SQLite.
5974: **
5975: ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
1.4.2.1 ! misho 5976: ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
! 5977: ** If a virtual table extension is
1.4 misho 5978: ** used with an SQLite version earlier than 3.8.2, the results of attempting
5979: ** to read or write the estimatedRows field are undefined (but are likely
5980: ** to included crashing the application). The estimatedRows field should
5981: ** therefore only be used if [sqlite3_libversion_number()] returns a
5982: ** value greater than or equal to 3008002. Similarly, the idxFlags field
1.4.2.1 ! misho 5983: ** was added for [version 3.9.0] ([dateof:3.9.0]).
! 5984: ** It may therefore only be used if
1.4 misho 5985: ** sqlite3_libversion_number() returns a value greater than or equal to
5986: ** 3009000.
1.2 misho 5987: */
5988: struct sqlite3_index_info {
5989: /* Inputs */
5990: int nConstraint; /* Number of entries in aConstraint */
5991: struct sqlite3_index_constraint {
1.4 misho 5992: int iColumn; /* Column constrained. -1 for ROWID */
1.2 misho 5993: unsigned char op; /* Constraint operator */
5994: unsigned char usable; /* True if this constraint is usable */
5995: int iTermOffset; /* Used internally - xBestIndex should ignore */
5996: } *aConstraint; /* Table of WHERE clause constraints */
5997: int nOrderBy; /* Number of terms in the ORDER BY clause */
5998: struct sqlite3_index_orderby {
5999: int iColumn; /* Column number */
6000: unsigned char desc; /* True for DESC. False for ASC. */
6001: } *aOrderBy; /* The ORDER BY clause */
6002: /* Outputs */
6003: struct sqlite3_index_constraint_usage {
6004: int argvIndex; /* if >0, constraint is part of argv to xFilter */
6005: unsigned char omit; /* Do not code a test for this constraint */
6006: } *aConstraintUsage;
6007: int idxNum; /* Number used to identify the index */
6008: char *idxStr; /* String, possibly obtained from sqlite3_malloc */
6009: int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
6010: int orderByConsumed; /* True if output is already ordered */
1.4 misho 6011: double estimatedCost; /* Estimated cost of using this index */
6012: /* Fields below are only available in SQLite 3.8.2 and later */
6013: sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
6014: /* Fields below are only available in SQLite 3.9.0 and later */
6015: int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */
6016: /* Fields below are only available in SQLite 3.10.0 and later */
6017: sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */
1.2 misho 6018: };
6019:
6020: /*
1.4 misho 6021: ** CAPI3REF: Virtual Table Scan Flags
6022: */
6023: #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */
6024:
6025: /*
1.2 misho 6026: ** CAPI3REF: Virtual Table Constraint Operator Codes
6027: **
6028: ** These macros defined the allowed values for the
6029: ** [sqlite3_index_info].aConstraint[].op field. Each value represents
6030: ** an operator that is part of a constraint term in the wHERE clause of
6031: ** a query that uses a [virtual table].
6032: */
1.4 misho 6033: #define SQLITE_INDEX_CONSTRAINT_EQ 2
6034: #define SQLITE_INDEX_CONSTRAINT_GT 4
6035: #define SQLITE_INDEX_CONSTRAINT_LE 8
6036: #define SQLITE_INDEX_CONSTRAINT_LT 16
6037: #define SQLITE_INDEX_CONSTRAINT_GE 32
6038: #define SQLITE_INDEX_CONSTRAINT_MATCH 64
6039: #define SQLITE_INDEX_CONSTRAINT_LIKE 65
6040: #define SQLITE_INDEX_CONSTRAINT_GLOB 66
6041: #define SQLITE_INDEX_CONSTRAINT_REGEXP 67
1.2 misho 6042:
6043: /*
6044: ** CAPI3REF: Register A Virtual Table Implementation
1.4 misho 6045: ** METHOD: sqlite3
1.2 misho 6046: **
6047: ** ^These routines are used to register a new [virtual table module] name.
6048: ** ^Module names must be registered before
6049: ** creating a new [virtual table] using the module and before using a
6050: ** preexisting [virtual table] for the module.
6051: **
6052: ** ^The module name is registered on the [database connection] specified
6053: ** by the first parameter. ^The name of the module is given by the
6054: ** second parameter. ^The third parameter is a pointer to
6055: ** the implementation of the [virtual table module]. ^The fourth
6056: ** parameter is an arbitrary client data pointer that is passed through
6057: ** into the [xCreate] and [xConnect] methods of the virtual table module
6058: ** when a new virtual table is be being created or reinitialized.
6059: **
6060: ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
6061: ** is a pointer to a destructor for the pClientData. ^SQLite will
6062: ** invoke the destructor function (if it is not NULL) when SQLite
6063: ** no longer needs the pClientData pointer. ^The destructor will also
6064: ** be invoked if the call to sqlite3_create_module_v2() fails.
6065: ** ^The sqlite3_create_module()
6066: ** interface is equivalent to sqlite3_create_module_v2() with a NULL
6067: ** destructor.
6068: */
6069: SQLITE_API int sqlite3_create_module(
6070: sqlite3 *db, /* SQLite connection to register module with */
6071: const char *zName, /* Name of the module */
6072: const sqlite3_module *p, /* Methods for the module */
6073: void *pClientData /* Client data for xCreate/xConnect */
6074: );
6075: SQLITE_API int sqlite3_create_module_v2(
6076: sqlite3 *db, /* SQLite connection to register module with */
6077: const char *zName, /* Name of the module */
6078: const sqlite3_module *p, /* Methods for the module */
6079: void *pClientData, /* Client data for xCreate/xConnect */
6080: void(*xDestroy)(void*) /* Module destructor function */
6081: );
6082:
6083: /*
6084: ** CAPI3REF: Virtual Table Instance Object
6085: ** KEYWORDS: sqlite3_vtab
6086: **
6087: ** Every [virtual table module] implementation uses a subclass
6088: ** of this object to describe a particular instance
6089: ** of the [virtual table]. Each subclass will
6090: ** be tailored to the specific needs of the module implementation.
6091: ** The purpose of this superclass is to define certain fields that are
6092: ** common to all module implementations.
6093: **
6094: ** ^Virtual tables methods can set an error message by assigning a
6095: ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
6096: ** take care that any prior string is freed by a call to [sqlite3_free()]
6097: ** prior to assigning a new string to zErrMsg. ^After the error message
6098: ** is delivered up to the client application, the string will be automatically
6099: ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
6100: */
6101: struct sqlite3_vtab {
6102: const sqlite3_module *pModule; /* The module for this virtual table */
1.4 misho 6103: int nRef; /* Number of open cursors */
1.2 misho 6104: char *zErrMsg; /* Error message from sqlite3_mprintf() */
6105: /* Virtual table implementations will typically add additional fields */
6106: };
6107:
6108: /*
6109: ** CAPI3REF: Virtual Table Cursor Object
6110: ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
6111: **
6112: ** Every [virtual table module] implementation uses a subclass of the
6113: ** following structure to describe cursors that point into the
6114: ** [virtual table] and are used
6115: ** to loop through the virtual table. Cursors are created using the
6116: ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
6117: ** by the [sqlite3_module.xClose | xClose] method. Cursors are used
6118: ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
6119: ** of the module. Each module implementation will define
6120: ** the content of a cursor structure to suit its own needs.
6121: **
6122: ** This superclass exists in order to define fields of the cursor that
6123: ** are common to all implementations.
6124: */
6125: struct sqlite3_vtab_cursor {
6126: sqlite3_vtab *pVtab; /* Virtual table of this cursor */
6127: /* Virtual table implementations will typically add additional fields */
6128: };
6129:
6130: /*
6131: ** CAPI3REF: Declare The Schema Of A Virtual Table
6132: **
6133: ** ^The [xCreate] and [xConnect] methods of a
6134: ** [virtual table module] call this interface
6135: ** to declare the format (the names and datatypes of the columns) of
6136: ** the virtual tables they implement.
6137: */
6138: SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
6139:
6140: /*
6141: ** CAPI3REF: Overload A Function For A Virtual Table
1.4 misho 6142: ** METHOD: sqlite3
1.2 misho 6143: **
6144: ** ^(Virtual tables can provide alternative implementations of functions
6145: ** using the [xFindFunction] method of the [virtual table module].
6146: ** But global versions of those functions
6147: ** must exist in order to be overloaded.)^
6148: **
6149: ** ^(This API makes sure a global version of a function with a particular
6150: ** name and number of parameters exists. If no such function exists
6151: ** before this API is called, a new function is created.)^ ^The implementation
6152: ** of the new function always causes an exception to be thrown. So
6153: ** the new function is not good for anything by itself. Its only
6154: ** purpose is to be a placeholder function that can be overloaded
6155: ** by a [virtual table].
6156: */
6157: SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
6158:
6159: /*
6160: ** The interface to the virtual-table mechanism defined above (back up
6161: ** to a comment remarkably similar to this one) is currently considered
6162: ** to be experimental. The interface might change in incompatible ways.
6163: ** If this is a problem for you, do not use the interface at this time.
6164: **
6165: ** When the virtual-table mechanism stabilizes, we will declare the
6166: ** interface fixed, support it indefinitely, and remove this comment.
6167: */
6168:
6169: /*
6170: ** CAPI3REF: A Handle To An Open BLOB
6171: ** KEYWORDS: {BLOB handle} {BLOB handles}
6172: **
6173: ** An instance of this object represents an open BLOB on which
6174: ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
6175: ** ^Objects of this type are created by [sqlite3_blob_open()]
6176: ** and destroyed by [sqlite3_blob_close()].
6177: ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
6178: ** can be used to read or write small subsections of the BLOB.
6179: ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
6180: */
6181: typedef struct sqlite3_blob sqlite3_blob;
6182:
6183: /*
6184: ** CAPI3REF: Open A BLOB For Incremental I/O
1.4 misho 6185: ** METHOD: sqlite3
6186: ** CONSTRUCTOR: sqlite3_blob
1.2 misho 6187: **
6188: ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
6189: ** in row iRow, column zColumn, table zTable in database zDb;
6190: ** in other words, the same BLOB that would be selected by:
6191: **
6192: ** <pre>
6193: ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
6194: ** </pre>)^
6195: **
1.4 misho 6196: ** ^(Parameter zDb is not the filename that contains the database, but
6197: ** rather the symbolic name of the database. For attached databases, this is
6198: ** the name that appears after the AS keyword in the [ATTACH] statement.
6199: ** For the main database file, the database name is "main". For TEMP
6200: ** tables, the database name is "temp".)^
6201: **
1.2 misho 6202: ** ^If the flags parameter is non-zero, then the BLOB is opened for read
1.4 misho 6203: ** and write access. ^If the flags parameter is zero, the BLOB is opened for
6204: ** read-only access.
6205: **
6206: ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
6207: ** in *ppBlob. Otherwise an [error code] is returned and, unless the error
6208: ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
6209: ** the API is not misused, it is always safe to call [sqlite3_blob_close()]
6210: ** on *ppBlob after this function it returns.
6211: **
6212: ** This function fails with SQLITE_ERROR if any of the following are true:
6213: ** <ul>
6214: ** <li> ^(Database zDb does not exist)^,
6215: ** <li> ^(Table zTable does not exist within database zDb)^,
6216: ** <li> ^(Table zTable is a WITHOUT ROWID table)^,
6217: ** <li> ^(Column zColumn does not exist)^,
6218: ** <li> ^(Row iRow is not present in the table)^,
6219: ** <li> ^(The specified column of row iRow contains a value that is not
6220: ** a TEXT or BLOB value)^,
6221: ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
6222: ** constraint and the blob is being opened for read/write access)^,
6223: ** <li> ^([foreign key constraints | Foreign key constraints] are enabled,
6224: ** column zColumn is part of a [child key] definition and the blob is
6225: ** being opened for read/write access)^.
6226: ** </ul>
6227: **
6228: ** ^Unless it returns SQLITE_MISUSE, this function sets the
6229: ** [database connection] error code and message accessible via
6230: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
6231: **
1.4.2.1 ! misho 6232: ** A BLOB referenced by sqlite3_blob_open() may be read using the
! 6233: ** [sqlite3_blob_read()] interface and modified by using
! 6234: ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a
! 6235: ** different row of the same table using the [sqlite3_blob_reopen()]
! 6236: ** interface. However, the column, table, or database of a [BLOB handle]
! 6237: ** cannot be changed after the [BLOB handle] is opened.
1.2 misho 6238: **
6239: ** ^(If the row that a BLOB handle points to is modified by an
6240: ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
6241: ** then the BLOB handle is marked as "expired".
6242: ** This is true if any column of the row is changed, even a column
6243: ** other than the one the BLOB handle is open on.)^
6244: ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
6245: ** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
6246: ** ^(Changes written into a BLOB prior to the BLOB expiring are not
6247: ** rolled back by the expiration of the BLOB. Such changes will eventually
6248: ** commit if the transaction continues to completion.)^
6249: **
6250: ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
6251: ** the opened blob. ^The size of a blob may not be changed by this
6252: ** interface. Use the [UPDATE] SQL command to change the size of a
6253: ** blob.
6254: **
6255: ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
1.4 misho 6256: ** and the built-in [zeroblob] SQL function may be used to create a
6257: ** zero-filled blob to read or write using the incremental-blob interface.
1.2 misho 6258: **
6259: ** To avoid a resource leak, every open [BLOB handle] should eventually
6260: ** be released by a call to [sqlite3_blob_close()].
1.4.2.1 ! misho 6261: **
! 6262: ** See also: [sqlite3_blob_close()],
! 6263: ** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
! 6264: ** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
1.2 misho 6265: */
6266: SQLITE_API int sqlite3_blob_open(
6267: sqlite3*,
6268: const char *zDb,
6269: const char *zTable,
6270: const char *zColumn,
6271: sqlite3_int64 iRow,
6272: int flags,
6273: sqlite3_blob **ppBlob
6274: );
6275:
6276: /*
6277: ** CAPI3REF: Move a BLOB Handle to a New Row
1.4 misho 6278: ** METHOD: sqlite3_blob
1.2 misho 6279: **
1.4.2.1 ! misho 6280: ** ^This function is used to move an existing [BLOB handle] so that it points
1.2 misho 6281: ** to a different row of the same database table. ^The new row is identified
6282: ** by the rowid value passed as the second argument. Only the row can be
6283: ** changed. ^The database, table and column on which the blob handle is open
1.4.2.1 ! misho 6284: ** remain the same. Moving an existing [BLOB handle] to a new row is
1.2 misho 6285: ** faster than closing the existing handle and opening a new one.
6286: **
6287: ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
6288: ** it must exist and there must be either a blob or text value stored in
6289: ** the nominated column.)^ ^If the new row is not present in the table, or if
6290: ** it does not contain a blob or text value, or if another error occurs, an
6291: ** SQLite error code is returned and the blob handle is considered aborted.
6292: ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
6293: ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
6294: ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
6295: ** always returns zero.
6296: **
6297: ** ^This function sets the database handle error code and message.
6298: */
1.4 misho 6299: SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
1.2 misho 6300:
6301: /*
6302: ** CAPI3REF: Close A BLOB Handle
1.4 misho 6303: ** DESTRUCTOR: sqlite3_blob
1.2 misho 6304: **
1.4 misho 6305: ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
6306: ** unconditionally. Even if this routine returns an error code, the
6307: ** handle is still closed.)^
6308: **
6309: ** ^If the blob handle being closed was opened for read-write access, and if
6310: ** the database is in auto-commit mode and there are no other open read-write
6311: ** blob handles or active write statements, the current transaction is
6312: ** committed. ^If an error occurs while committing the transaction, an error
6313: ** code is returned and the transaction rolled back.
6314: **
6315: ** Calling this function with an argument that is not a NULL pointer or an
6316: ** open blob handle results in undefined behaviour. ^Calling this routine
6317: ** with a null pointer (such as would be returned by a failed call to
6318: ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
6319: ** is passed a valid open blob handle, the values returned by the
6320: ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
1.2 misho 6321: */
6322: SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
6323:
6324: /*
6325: ** CAPI3REF: Return The Size Of An Open BLOB
1.4 misho 6326: ** METHOD: sqlite3_blob
1.2 misho 6327: **
6328: ** ^Returns the size in bytes of the BLOB accessible via the
6329: ** successfully opened [BLOB handle] in its only argument. ^The
6330: ** incremental blob I/O routines can only read or overwriting existing
6331: ** blob content; they cannot change the size of a blob.
6332: **
6333: ** This routine only works on a [BLOB handle] which has been created
6334: ** by a prior successful call to [sqlite3_blob_open()] and which has not
6335: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
6336: ** to this routine results in undefined and probably undesirable behavior.
6337: */
6338: SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
6339:
6340: /*
6341: ** CAPI3REF: Read Data From A BLOB Incrementally
1.4 misho 6342: ** METHOD: sqlite3_blob
1.2 misho 6343: **
6344: ** ^(This function is used to read data from an open [BLOB handle] into a
6345: ** caller-supplied buffer. N bytes of data are copied into buffer Z
6346: ** from the open BLOB, starting at offset iOffset.)^
6347: **
6348: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
6349: ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
6350: ** less than zero, [SQLITE_ERROR] is returned and no data is read.
6351: ** ^The size of the blob (and hence the maximum value of N+iOffset)
6352: ** can be determined using the [sqlite3_blob_bytes()] interface.
6353: **
6354: ** ^An attempt to read from an expired [BLOB handle] fails with an
6355: ** error code of [SQLITE_ABORT].
6356: **
6357: ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
6358: ** Otherwise, an [error code] or an [extended error code] is returned.)^
6359: **
6360: ** This routine only works on a [BLOB handle] which has been created
6361: ** by a prior successful call to [sqlite3_blob_open()] and which has not
6362: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
6363: ** to this routine results in undefined and probably undesirable behavior.
6364: **
6365: ** See also: [sqlite3_blob_write()].
6366: */
6367: SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
6368:
6369: /*
6370: ** CAPI3REF: Write Data Into A BLOB Incrementally
1.4 misho 6371: ** METHOD: sqlite3_blob
1.2 misho 6372: **
1.4 misho 6373: ** ^(This function is used to write data into an open [BLOB handle] from a
6374: ** caller-supplied buffer. N bytes of data are copied from the buffer Z
6375: ** into the open BLOB, starting at offset iOffset.)^
6376: **
6377: ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
6378: ** Otherwise, an [error code] or an [extended error code] is returned.)^
6379: ** ^Unless SQLITE_MISUSE is returned, this function sets the
6380: ** [database connection] error code and message accessible via
6381: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
1.2 misho 6382: **
6383: ** ^If the [BLOB handle] passed as the first argument was not opened for
6384: ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
6385: ** this function returns [SQLITE_READONLY].
6386: **
1.4 misho 6387: ** This function may only modify the contents of the BLOB; it is
1.2 misho 6388: ** not possible to increase the size of a BLOB using this API.
6389: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
1.4 misho 6390: ** [SQLITE_ERROR] is returned and no data is written. The size of the
6391: ** BLOB (and hence the maximum value of N+iOffset) can be determined
6392: ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
6393: ** than zero [SQLITE_ERROR] is returned and no data is written.
1.2 misho 6394: **
6395: ** ^An attempt to write to an expired [BLOB handle] fails with an
6396: ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
6397: ** before the [BLOB handle] expired are not rolled back by the
6398: ** expiration of the handle, though of course those changes might
6399: ** have been overwritten by the statement that expired the BLOB handle
6400: ** or by other independent statements.
6401: **
6402: ** This routine only works on a [BLOB handle] which has been created
6403: ** by a prior successful call to [sqlite3_blob_open()] and which has not
6404: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
6405: ** to this routine results in undefined and probably undesirable behavior.
6406: **
6407: ** See also: [sqlite3_blob_read()].
6408: */
6409: SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
6410:
6411: /*
6412: ** CAPI3REF: Virtual File System Objects
6413: **
6414: ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
6415: ** that SQLite uses to interact
6416: ** with the underlying operating system. Most SQLite builds come with a
6417: ** single default VFS that is appropriate for the host computer.
6418: ** New VFSes can be registered and existing VFSes can be unregistered.
6419: ** The following interfaces are provided.
6420: **
6421: ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
6422: ** ^Names are case sensitive.
6423: ** ^Names are zero-terminated UTF-8 strings.
6424: ** ^If there is no match, a NULL pointer is returned.
6425: ** ^If zVfsName is NULL then the default VFS is returned.
6426: **
6427: ** ^New VFSes are registered with sqlite3_vfs_register().
6428: ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
6429: ** ^The same VFS can be registered multiple times without injury.
6430: ** ^To make an existing VFS into the default VFS, register it again
6431: ** with the makeDflt flag set. If two different VFSes with the
6432: ** same name are registered, the behavior is undefined. If a
6433: ** VFS is registered with a name that is NULL or an empty string,
6434: ** then the behavior is undefined.
6435: **
6436: ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
6437: ** ^(If the default VFS is unregistered, another VFS is chosen as
6438: ** the default. The choice for the new VFS is arbitrary.)^
6439: */
6440: SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
6441: SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
6442: SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
6443:
6444: /*
6445: ** CAPI3REF: Mutexes
6446: **
6447: ** The SQLite core uses these routines for thread
6448: ** synchronization. Though they are intended for internal
6449: ** use by SQLite, code that links against SQLite is
6450: ** permitted to use any of these routines.
6451: **
6452: ** The SQLite source code contains multiple implementations
6453: ** of these mutex routines. An appropriate implementation
1.4 misho 6454: ** is selected automatically at compile-time. The following
1.2 misho 6455: ** implementations are available in the SQLite core:
6456: **
6457: ** <ul>
6458: ** <li> SQLITE_MUTEX_PTHREADS
6459: ** <li> SQLITE_MUTEX_W32
6460: ** <li> SQLITE_MUTEX_NOOP
1.4 misho 6461: ** </ul>
1.2 misho 6462: **
1.4 misho 6463: ** The SQLITE_MUTEX_NOOP implementation is a set of routines
1.2 misho 6464: ** that does no real locking and is appropriate for use in
1.4 misho 6465: ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and
1.3 misho 6466: ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
6467: ** and Windows.
1.2 misho 6468: **
1.4 misho 6469: ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
1.2 misho 6470: ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
6471: ** implementation is included with the library. In this case the
6472: ** application must supply a custom mutex implementation using the
6473: ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
6474: ** before calling sqlite3_initialize() or any other public sqlite3_
1.4 misho 6475: ** function that calls sqlite3_initialize().
1.2 misho 6476: **
6477: ** ^The sqlite3_mutex_alloc() routine allocates a new
1.4 misho 6478: ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
6479: ** routine returns NULL if it is unable to allocate the requested
6480: ** mutex. The argument to sqlite3_mutex_alloc() must one of these
6481: ** integer constants:
1.2 misho 6482: **
6483: ** <ul>
6484: ** <li> SQLITE_MUTEX_FAST
6485: ** <li> SQLITE_MUTEX_RECURSIVE
6486: ** <li> SQLITE_MUTEX_STATIC_MASTER
6487: ** <li> SQLITE_MUTEX_STATIC_MEM
1.4 misho 6488: ** <li> SQLITE_MUTEX_STATIC_OPEN
1.2 misho 6489: ** <li> SQLITE_MUTEX_STATIC_PRNG
6490: ** <li> SQLITE_MUTEX_STATIC_LRU
1.4 misho 6491: ** <li> SQLITE_MUTEX_STATIC_PMEM
6492: ** <li> SQLITE_MUTEX_STATIC_APP1
6493: ** <li> SQLITE_MUTEX_STATIC_APP2
6494: ** <li> SQLITE_MUTEX_STATIC_APP3
6495: ** <li> SQLITE_MUTEX_STATIC_VFS1
6496: ** <li> SQLITE_MUTEX_STATIC_VFS2
6497: ** <li> SQLITE_MUTEX_STATIC_VFS3
6498: ** </ul>
1.2 misho 6499: **
6500: ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
6501: ** cause sqlite3_mutex_alloc() to create
6502: ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
6503: ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
6504: ** The mutex implementation does not need to make a distinction
6505: ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
1.4 misho 6506: ** not want to. SQLite will only request a recursive mutex in
6507: ** cases where it really needs one. If a faster non-recursive mutex
1.2 misho 6508: ** implementation is available on the host platform, the mutex subsystem
6509: ** might return such a mutex in response to SQLITE_MUTEX_FAST.
6510: **
6511: ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
6512: ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
1.4 misho 6513: ** a pointer to a static preexisting mutex. ^Nine static mutexes are
1.2 misho 6514: ** used by the current version of SQLite. Future versions of SQLite
6515: ** may add additional static mutexes. Static mutexes are for internal
6516: ** use by SQLite only. Applications that use SQLite mutexes should
6517: ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
6518: ** SQLITE_MUTEX_RECURSIVE.
6519: **
6520: ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
6521: ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
1.4 misho 6522: ** returns a different mutex on every call. ^For the static
1.2 misho 6523: ** mutex types, the same mutex is returned on every call that has
6524: ** the same type number.
6525: **
6526: ** ^The sqlite3_mutex_free() routine deallocates a previously
1.4 misho 6527: ** allocated dynamic mutex. Attempting to deallocate a static
6528: ** mutex results in undefined behavior.
1.2 misho 6529: **
6530: ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
6531: ** to enter a mutex. ^If another thread is already within the mutex,
6532: ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
6533: ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
6534: ** upon successful entry. ^(Mutexes created using
6535: ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
1.4 misho 6536: ** In such cases, the
1.2 misho 6537: ** mutex must be exited an equal number of times before another thread
1.4 misho 6538: ** can enter.)^ If the same thread tries to enter any mutex other
6539: ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
1.2 misho 6540: **
6541: ** ^(Some systems (for example, Windows 95) do not support the operation
6542: ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
1.4 misho 6543: ** will always return SQLITE_BUSY. The SQLite core only ever uses
6544: ** sqlite3_mutex_try() as an optimization so this is acceptable
6545: ** behavior.)^
1.2 misho 6546: **
6547: ** ^The sqlite3_mutex_leave() routine exits a mutex that was
1.4 misho 6548: ** previously entered by the same thread. The behavior
1.2 misho 6549: ** is undefined if the mutex is not currently entered by the
1.4 misho 6550: ** calling thread or is not currently allocated.
1.2 misho 6551: **
6552: ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
6553: ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
6554: ** behave as no-ops.
6555: **
6556: ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
6557: */
6558: SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
6559: SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
6560: SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
6561: SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
6562: SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
6563:
6564: /*
6565: ** CAPI3REF: Mutex Methods Object
6566: **
6567: ** An instance of this structure defines the low-level routines
6568: ** used to allocate and use mutexes.
6569: **
6570: ** Usually, the default mutex implementations provided by SQLite are
1.4 misho 6571: ** sufficient, however the application has the option of substituting a custom
1.2 misho 6572: ** implementation for specialized deployments or systems for which SQLite
1.4 misho 6573: ** does not provide a suitable implementation. In this case, the application
1.2 misho 6574: ** creates and populates an instance of this structure to pass
6575: ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
6576: ** Additionally, an instance of this structure can be used as an
6577: ** output variable when querying the system for the current mutex
6578: ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
6579: **
6580: ** ^The xMutexInit method defined by this structure is invoked as
6581: ** part of system initialization by the sqlite3_initialize() function.
6582: ** ^The xMutexInit routine is called by SQLite exactly once for each
6583: ** effective call to [sqlite3_initialize()].
6584: **
6585: ** ^The xMutexEnd method defined by this structure is invoked as
6586: ** part of system shutdown by the sqlite3_shutdown() function. The
6587: ** implementation of this method is expected to release all outstanding
6588: ** resources obtained by the mutex methods implementation, especially
6589: ** those obtained by the xMutexInit method. ^The xMutexEnd()
6590: ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
6591: **
6592: ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
6593: ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
6594: ** xMutexNotheld) implement the following interfaces (respectively):
6595: **
6596: ** <ul>
6597: ** <li> [sqlite3_mutex_alloc()] </li>
6598: ** <li> [sqlite3_mutex_free()] </li>
6599: ** <li> [sqlite3_mutex_enter()] </li>
6600: ** <li> [sqlite3_mutex_try()] </li>
6601: ** <li> [sqlite3_mutex_leave()] </li>
6602: ** <li> [sqlite3_mutex_held()] </li>
6603: ** <li> [sqlite3_mutex_notheld()] </li>
6604: ** </ul>)^
6605: **
6606: ** The only difference is that the public sqlite3_XXX functions enumerated
6607: ** above silently ignore any invocations that pass a NULL pointer instead
6608: ** of a valid mutex handle. The implementations of the methods defined
6609: ** by this structure are not required to handle this case, the results
6610: ** of passing a NULL pointer instead of a valid mutex handle are undefined
6611: ** (i.e. it is acceptable to provide an implementation that segfaults if
6612: ** it is passed a NULL pointer).
6613: **
1.4 misho 6614: ** The xMutexInit() method must be threadsafe. It must be harmless to
1.2 misho 6615: ** invoke xMutexInit() multiple times within the same process and without
6616: ** intervening calls to xMutexEnd(). Second and subsequent calls to
6617: ** xMutexInit() must be no-ops.
6618: **
1.4 misho 6619: ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
6620: ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory
1.2 misho 6621: ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
6622: ** memory allocation for a fast or recursive mutex.
6623: **
6624: ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
6625: ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
6626: ** If xMutexInit fails in any way, it is expected to clean up after itself
6627: ** prior to returning.
6628: */
6629: typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
6630: struct sqlite3_mutex_methods {
6631: int (*xMutexInit)(void);
6632: int (*xMutexEnd)(void);
6633: sqlite3_mutex *(*xMutexAlloc)(int);
6634: void (*xMutexFree)(sqlite3_mutex *);
6635: void (*xMutexEnter)(sqlite3_mutex *);
6636: int (*xMutexTry)(sqlite3_mutex *);
6637: void (*xMutexLeave)(sqlite3_mutex *);
6638: int (*xMutexHeld)(sqlite3_mutex *);
6639: int (*xMutexNotheld)(sqlite3_mutex *);
6640: };
6641:
6642: /*
6643: ** CAPI3REF: Mutex Verification Routines
6644: **
6645: ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
1.4 misho 6646: ** are intended for use inside assert() statements. The SQLite core
1.2 misho 6647: ** never uses these routines except inside an assert() and applications
1.4 misho 6648: ** are advised to follow the lead of the core. The SQLite core only
1.2 misho 6649: ** provides implementations for these routines when it is compiled
1.4 misho 6650: ** with the SQLITE_DEBUG flag. External mutex implementations
1.2 misho 6651: ** are only required to provide these routines if SQLITE_DEBUG is
6652: ** defined and if NDEBUG is not defined.
6653: **
1.4 misho 6654: ** These routines should return true if the mutex in their argument
1.2 misho 6655: ** is held or not held, respectively, by the calling thread.
6656: **
1.4 misho 6657: ** The implementation is not required to provide versions of these
1.2 misho 6658: ** routines that actually work. If the implementation does not provide working
6659: ** versions of these routines, it should at least provide stubs that always
6660: ** return true so that one does not get spurious assertion failures.
6661: **
1.4 misho 6662: ** If the argument to sqlite3_mutex_held() is a NULL pointer then
1.2 misho 6663: ** the routine should return 1. This seems counter-intuitive since
6664: ** clearly the mutex cannot be held if it does not exist. But
6665: ** the reason the mutex does not exist is because the build is not
6666: ** using mutexes. And we do not want the assert() containing the
6667: ** call to sqlite3_mutex_held() to fail, so a non-zero return is
1.4 misho 6668: ** the appropriate thing to do. The sqlite3_mutex_notheld()
1.2 misho 6669: ** interface should also return 1 when given a NULL pointer.
6670: */
6671: #ifndef NDEBUG
6672: SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
6673: SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
6674: #endif
6675:
6676: /*
6677: ** CAPI3REF: Mutex Types
6678: **
6679: ** The [sqlite3_mutex_alloc()] interface takes a single argument
6680: ** which is one of these integer constants.
6681: **
6682: ** The set of static mutexes may change from one SQLite release to the
6683: ** next. Applications that override the built-in mutex logic must be
6684: ** prepared to accommodate additional static mutexes.
6685: */
6686: #define SQLITE_MUTEX_FAST 0
6687: #define SQLITE_MUTEX_RECURSIVE 1
6688: #define SQLITE_MUTEX_STATIC_MASTER 2
6689: #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
6690: #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
6691: #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
1.4.2.1 ! misho 6692: #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */
1.2 misho 6693: #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
6694: #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
6695: #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
1.4 misho 6696: #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */
6697: #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */
6698: #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */
6699: #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */
6700: #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */
6701: #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */
1.2 misho 6702:
6703: /*
6704: ** CAPI3REF: Retrieve the mutex for a database connection
1.4 misho 6705: ** METHOD: sqlite3
1.2 misho 6706: **
6707: ** ^This interface returns a pointer the [sqlite3_mutex] object that
6708: ** serializes access to the [database connection] given in the argument
6709: ** when the [threading mode] is Serialized.
6710: ** ^If the [threading mode] is Single-thread or Multi-thread then this
6711: ** routine returns a NULL pointer.
6712: */
6713: SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
6714:
6715: /*
6716: ** CAPI3REF: Low-Level Control Of Database Files
1.4 misho 6717: ** METHOD: sqlite3
1.2 misho 6718: **
6719: ** ^The [sqlite3_file_control()] interface makes a direct call to the
6720: ** xFileControl method for the [sqlite3_io_methods] object associated
6721: ** with a particular database identified by the second argument. ^The
6722: ** name of the database is "main" for the main database or "temp" for the
6723: ** TEMP database, or the name that appears after the AS keyword for
6724: ** databases that are added using the [ATTACH] SQL command.
6725: ** ^A NULL pointer can be used in place of "main" to refer to the
6726: ** main database file.
6727: ** ^The third and fourth parameters to this routine
6728: ** are passed directly through to the second and third parameters of
6729: ** the xFileControl method. ^The return value of the xFileControl
6730: ** method becomes the return value of this routine.
6731: **
6732: ** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
6733: ** a pointer to the underlying [sqlite3_file] object to be written into
6734: ** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER
6735: ** case is a short-circuit path which does not actually invoke the
6736: ** underlying sqlite3_io_methods.xFileControl method.
6737: **
6738: ** ^If the second parameter (zDbName) does not match the name of any
6739: ** open database file, then SQLITE_ERROR is returned. ^This error
6740: ** code is not remembered and will not be recalled by [sqlite3_errcode()]
6741: ** or [sqlite3_errmsg()]. The underlying xFileControl method might
6742: ** also return SQLITE_ERROR. There is no way to distinguish between
6743: ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
6744: ** xFileControl method.
6745: **
6746: ** See also: [SQLITE_FCNTL_LOCKSTATE]
6747: */
6748: SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
6749:
6750: /*
6751: ** CAPI3REF: Testing Interface
6752: **
6753: ** ^The sqlite3_test_control() interface is used to read out internal
6754: ** state of SQLite and to inject faults into SQLite for testing
6755: ** purposes. ^The first parameter is an operation code that determines
6756: ** the number, meaning, and operation of all subsequent parameters.
6757: **
6758: ** This interface is not for use by applications. It exists solely
6759: ** for verifying the correct operation of the SQLite library. Depending
6760: ** on how the SQLite library is compiled, this interface might not exist.
6761: **
6762: ** The details of the operation codes, their meanings, the parameters
6763: ** they take, and what they do are all subject to change without notice.
6764: ** Unlike most of the SQLite API, this function is not guaranteed to
6765: ** operate consistently from one release to the next.
6766: */
6767: SQLITE_API int sqlite3_test_control(int op, ...);
6768:
6769: /*
6770: ** CAPI3REF: Testing Interface Operation Codes
6771: **
6772: ** These constants are the valid operation code parameters used
6773: ** as the first argument to [sqlite3_test_control()].
6774: **
6775: ** These parameters and their meanings are subject to change
6776: ** without notice. These values are for testing purposes only.
6777: ** Applications should not use any of these parameters or the
6778: ** [sqlite3_test_control()] interface.
6779: */
6780: #define SQLITE_TESTCTRL_FIRST 5
6781: #define SQLITE_TESTCTRL_PRNG_SAVE 5
6782: #define SQLITE_TESTCTRL_PRNG_RESTORE 6
6783: #define SQLITE_TESTCTRL_PRNG_RESET 7
6784: #define SQLITE_TESTCTRL_BITVEC_TEST 8
6785: #define SQLITE_TESTCTRL_FAULT_INSTALL 9
6786: #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
6787: #define SQLITE_TESTCTRL_PENDING_BYTE 11
6788: #define SQLITE_TESTCTRL_ASSERT 12
6789: #define SQLITE_TESTCTRL_ALWAYS 13
6790: #define SQLITE_TESTCTRL_RESERVE 14
6791: #define SQLITE_TESTCTRL_OPTIMIZATIONS 15
6792: #define SQLITE_TESTCTRL_ISKEYWORD 16
6793: #define SQLITE_TESTCTRL_SCRATCHMALLOC 17
6794: #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
1.4 misho 6795: #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */
1.4.2.1 ! misho 6796: #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19
1.4 misho 6797: #define SQLITE_TESTCTRL_NEVER_CORRUPT 20
6798: #define SQLITE_TESTCTRL_VDBE_COVERAGE 21
6799: #define SQLITE_TESTCTRL_BYTEORDER 22
6800: #define SQLITE_TESTCTRL_ISINIT 23
6801: #define SQLITE_TESTCTRL_SORTER_MMAP 24
6802: #define SQLITE_TESTCTRL_IMPOSTER 25
6803: #define SQLITE_TESTCTRL_LAST 25
1.2 misho 6804:
6805: /*
6806: ** CAPI3REF: SQLite Runtime Status
6807: **
1.4 misho 6808: ** ^These interfaces are used to retrieve runtime status information
1.2 misho 6809: ** about the performance of SQLite, and optionally to reset various
6810: ** highwater marks. ^The first argument is an integer code for
6811: ** the specific parameter to measure. ^(Recognized integer codes
6812: ** are of the form [status parameters | SQLITE_STATUS_...].)^
6813: ** ^The current value of the parameter is returned into *pCurrent.
6814: ** ^The highest recorded value is returned in *pHighwater. ^If the
6815: ** resetFlag is true, then the highest record value is reset after
6816: ** *pHighwater is written. ^(Some parameters do not record the highest
6817: ** value. For those parameters
6818: ** nothing is written into *pHighwater and the resetFlag is ignored.)^
6819: ** ^(Other parameters record only the highwater mark and not the current
6820: ** value. For these latter parameters nothing is written into *pCurrent.)^
6821: **
1.4 misho 6822: ** ^The sqlite3_status() and sqlite3_status64() routines return
6823: ** SQLITE_OK on success and a non-zero [error code] on failure.
1.2 misho 6824: **
1.4 misho 6825: ** If either the current value or the highwater mark is too large to
6826: ** be represented by a 32-bit integer, then the values returned by
6827: ** sqlite3_status() are undefined.
1.2 misho 6828: **
6829: ** See also: [sqlite3_db_status()]
6830: */
6831: SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
1.4 misho 6832: SQLITE_API int sqlite3_status64(
6833: int op,
6834: sqlite3_int64 *pCurrent,
6835: sqlite3_int64 *pHighwater,
6836: int resetFlag
6837: );
1.2 misho 6838:
6839:
6840: /*
6841: ** CAPI3REF: Status Parameters
6842: ** KEYWORDS: {status parameters}
6843: **
6844: ** These integer constants designate various run-time status parameters
6845: ** that can be returned by [sqlite3_status()].
6846: **
6847: ** <dl>
6848: ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
6849: ** <dd>This parameter is the current amount of memory checked out
6850: ** using [sqlite3_malloc()], either directly or indirectly. The
6851: ** figure includes calls made to [sqlite3_malloc()] by the application
6852: ** and internal memory usage by the SQLite library. Scratch memory
6853: ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
6854: ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
6855: ** this parameter. The amount returned is the sum of the allocation
6856: ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
6857: **
6858: ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
6859: ** <dd>This parameter records the largest memory allocation request
6860: ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
6861: ** internal equivalents). Only the value returned in the
6862: ** *pHighwater parameter to [sqlite3_status()] is of interest.
6863: ** The value written into the *pCurrent parameter is undefined.</dd>)^
6864: **
6865: ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
6866: ** <dd>This parameter records the number of separate memory allocations
6867: ** currently checked out.</dd>)^
6868: **
6869: ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
6870: ** <dd>This parameter returns the number of pages used out of the
6871: ** [pagecache memory allocator] that was configured using
6872: ** [SQLITE_CONFIG_PAGECACHE]. The
6873: ** value returned is in pages, not in bytes.</dd>)^
6874: **
6875: ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
6876: ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
6877: ** <dd>This parameter returns the number of bytes of page cache
6878: ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
6879: ** buffer and where forced to overflow to [sqlite3_malloc()]. The
6880: ** returned value includes allocations that overflowed because they
6881: ** where too large (they were larger than the "sz" parameter to
6882: ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
6883: ** no space was left in the page cache.</dd>)^
6884: **
6885: ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
6886: ** <dd>This parameter records the largest memory allocation request
6887: ** handed to [pagecache memory allocator]. Only the value returned in the
6888: ** *pHighwater parameter to [sqlite3_status()] is of interest.
6889: ** The value written into the *pCurrent parameter is undefined.</dd>)^
6890: **
6891: ** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
6892: ** <dd>This parameter returns the number of allocations used out of the
6893: ** [scratch memory allocator] configured using
6894: ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
6895: ** in bytes. Since a single thread may only have one scratch allocation
6896: ** outstanding at time, this parameter also reports the number of threads
6897: ** using scratch memory at the same time.</dd>)^
6898: **
6899: ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
6900: ** <dd>This parameter returns the number of bytes of scratch memory
6901: ** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
6902: ** buffer and where forced to overflow to [sqlite3_malloc()]. The values
6903: ** returned include overflows because the requested allocation was too
6904: ** larger (that is, because the requested allocation was larger than the
6905: ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
6906: ** slots were available.
6907: ** </dd>)^
6908: **
6909: ** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
6910: ** <dd>This parameter records the largest memory allocation request
6911: ** handed to [scratch memory allocator]. Only the value returned in the
6912: ** *pHighwater parameter to [sqlite3_status()] is of interest.
6913: ** The value written into the *pCurrent parameter is undefined.</dd>)^
6914: **
6915: ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
1.4 misho 6916: ** <dd>The *pHighwater parameter records the deepest parser stack.
6917: ** The *pCurrent value is undefined. The *pHighwater value is only
1.2 misho 6918: ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
6919: ** </dl>
6920: **
6921: ** New status parameters may be added from time to time.
6922: */
6923: #define SQLITE_STATUS_MEMORY_USED 0
6924: #define SQLITE_STATUS_PAGECACHE_USED 1
6925: #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
6926: #define SQLITE_STATUS_SCRATCH_USED 3
6927: #define SQLITE_STATUS_SCRATCH_OVERFLOW 4
6928: #define SQLITE_STATUS_MALLOC_SIZE 5
6929: #define SQLITE_STATUS_PARSER_STACK 6
6930: #define SQLITE_STATUS_PAGECACHE_SIZE 7
6931: #define SQLITE_STATUS_SCRATCH_SIZE 8
6932: #define SQLITE_STATUS_MALLOC_COUNT 9
6933:
6934: /*
6935: ** CAPI3REF: Database Connection Status
1.4 misho 6936: ** METHOD: sqlite3
1.2 misho 6937: **
6938: ** ^This interface is used to retrieve runtime status information
6939: ** about a single [database connection]. ^The first argument is the
6940: ** database connection object to be interrogated. ^The second argument
6941: ** is an integer constant, taken from the set of
6942: ** [SQLITE_DBSTATUS options], that
6943: ** determines the parameter to interrogate. The set of
6944: ** [SQLITE_DBSTATUS options] is likely
6945: ** to grow in future releases of SQLite.
6946: **
6947: ** ^The current value of the requested parameter is written into *pCur
6948: ** and the highest instantaneous value is written into *pHiwtr. ^If
6949: ** the resetFlg is true, then the highest instantaneous value is
6950: ** reset back down to the current value.
6951: **
6952: ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
6953: ** non-zero [error code] on failure.
6954: **
6955: ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
6956: */
6957: SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
6958:
6959: /*
6960: ** CAPI3REF: Status Parameters for database connections
6961: ** KEYWORDS: {SQLITE_DBSTATUS options}
6962: **
6963: ** These constants are the available integer "verbs" that can be passed as
6964: ** the second argument to the [sqlite3_db_status()] interface.
6965: **
6966: ** New verbs may be added in future releases of SQLite. Existing verbs
6967: ** might be discontinued. Applications should check the return code from
6968: ** [sqlite3_db_status()] to make sure that the call worked.
6969: ** The [sqlite3_db_status()] interface will return a non-zero error code
6970: ** if a discontinued or unsupported verb is invoked.
6971: **
6972: ** <dl>
6973: ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
6974: ** <dd>This parameter returns the number of lookaside memory slots currently
6975: ** checked out.</dd>)^
6976: **
6977: ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
6978: ** <dd>This parameter returns the number malloc attempts that were
6979: ** satisfied using lookaside memory. Only the high-water value is meaningful;
6980: ** the current value is always zero.)^
6981: **
6982: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
6983: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
6984: ** <dd>This parameter returns the number malloc attempts that might have
6985: ** been satisfied using lookaside memory but failed due to the amount of
6986: ** memory requested being larger than the lookaside slot size.
6987: ** Only the high-water value is meaningful;
6988: ** the current value is always zero.)^
6989: **
6990: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
6991: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
6992: ** <dd>This parameter returns the number malloc attempts that might have
6993: ** been satisfied using lookaside memory but failed due to all lookaside
6994: ** memory already being in use.
6995: ** Only the high-water value is meaningful;
6996: ** the current value is always zero.)^
6997: **
6998: ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
1.4 misho 6999: ** <dd>This parameter returns the approximate number of bytes of heap
1.2 misho 7000: ** memory used by all pager caches associated with the database connection.)^
7001: ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
7002: **
1.4 misho 7003: ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
7004: ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
7005: ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
7006: ** pager cache is shared between two or more connections the bytes of heap
7007: ** memory used by that pager cache is divided evenly between the attached
7008: ** connections.)^ In other words, if none of the pager caches associated
7009: ** with the database connection are shared, this request returns the same
7010: ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
7011: ** shared, the value returned by this call will be smaller than that returned
7012: ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
7013: ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
7014: **
1.2 misho 7015: ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
1.4 misho 7016: ** <dd>This parameter returns the approximate number of bytes of heap
1.2 misho 7017: ** memory used to store the schema for all databases associated
7018: ** with the connection - main, temp, and any [ATTACH]-ed databases.)^
7019: ** ^The full amount of memory used by the schemas is reported, even if the
7020: ** schema memory is shared with other database connections due to
7021: ** [shared cache mode] being enabled.
7022: ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
7023: **
7024: ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
1.4 misho 7025: ** <dd>This parameter returns the approximate number of bytes of heap
1.2 misho 7026: ** and lookaside memory used by all prepared statements associated with
7027: ** the database connection.)^
7028: ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
7029: ** </dd>
7030: **
7031: ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
7032: ** <dd>This parameter returns the number of pager cache hits that have
7033: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
7034: ** is always 0.
7035: ** </dd>
7036: **
7037: ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
7038: ** <dd>This parameter returns the number of pager cache misses that have
7039: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
7040: ** is always 0.
7041: ** </dd>
1.3 misho 7042: **
7043: ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
7044: ** <dd>This parameter returns the number of dirty cache entries that have
7045: ** been written to disk. Specifically, the number of pages written to the
7046: ** wal file in wal mode databases, or the number of pages written to the
7047: ** database file in rollback mode databases. Any pages written as part of
7048: ** transaction rollback or database recovery operations are not included.
7049: ** If an IO or other error occurs while writing a page to disk, the effect
7050: ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
7051: ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
7052: ** </dd>
1.4 misho 7053: **
7054: ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
7055: ** <dd>This parameter returns zero for the current value if and only if
7056: ** all foreign key constraints (deferred or immediate) have been
7057: ** resolved.)^ ^The highwater mark is always 0.
7058: ** </dd>
1.2 misho 7059: ** </dl>
7060: */
7061: #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
7062: #define SQLITE_DBSTATUS_CACHE_USED 1
7063: #define SQLITE_DBSTATUS_SCHEMA_USED 2
7064: #define SQLITE_DBSTATUS_STMT_USED 3
7065: #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
7066: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
7067: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
7068: #define SQLITE_DBSTATUS_CACHE_HIT 7
7069: #define SQLITE_DBSTATUS_CACHE_MISS 8
1.3 misho 7070: #define SQLITE_DBSTATUS_CACHE_WRITE 9
1.4 misho 7071: #define SQLITE_DBSTATUS_DEFERRED_FKS 10
7072: #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11
7073: #define SQLITE_DBSTATUS_MAX 11 /* Largest defined DBSTATUS */
1.2 misho 7074:
7075:
7076: /*
7077: ** CAPI3REF: Prepared Statement Status
1.4 misho 7078: ** METHOD: sqlite3_stmt
1.2 misho 7079: **
7080: ** ^(Each prepared statement maintains various
7081: ** [SQLITE_STMTSTATUS counters] that measure the number
7082: ** of times it has performed specific operations.)^ These counters can
7083: ** be used to monitor the performance characteristics of the prepared
7084: ** statements. For example, if the number of table steps greatly exceeds
7085: ** the number of table searches or result rows, that would tend to indicate
7086: ** that the prepared statement is using a full table scan rather than
7087: ** an index.
7088: **
7089: ** ^(This interface is used to retrieve and reset counter values from
7090: ** a [prepared statement]. The first argument is the prepared statement
7091: ** object to be interrogated. The second argument
7092: ** is an integer code for a specific [SQLITE_STMTSTATUS counter]
7093: ** to be interrogated.)^
7094: ** ^The current value of the requested counter is returned.
7095: ** ^If the resetFlg is true, then the counter is reset to zero after this
7096: ** interface call returns.
7097: **
7098: ** See also: [sqlite3_status()] and [sqlite3_db_status()].
7099: */
7100: SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
7101:
7102: /*
7103: ** CAPI3REF: Status Parameters for prepared statements
7104: ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
7105: **
7106: ** These preprocessor macros define integer codes that name counter
7107: ** values associated with the [sqlite3_stmt_status()] interface.
7108: ** The meanings of the various counters are as follows:
7109: **
7110: ** <dl>
7111: ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
7112: ** <dd>^This is the number of times that SQLite has stepped forward in
7113: ** a table as part of a full table scan. Large numbers for this counter
7114: ** may indicate opportunities for performance improvement through
7115: ** careful use of indices.</dd>
7116: **
7117: ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
7118: ** <dd>^This is the number of sort operations that have occurred.
7119: ** A non-zero value in this counter may indicate an opportunity to
7120: ** improvement performance through careful use of indices.</dd>
7121: **
7122: ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
7123: ** <dd>^This is the number of rows inserted into transient indices that
7124: ** were created automatically in order to help joins run faster.
7125: ** A non-zero value in this counter may indicate an opportunity to
7126: ** improvement performance by adding permanent indices that do not
7127: ** need to be reinitialized each time the statement is run.</dd>
1.4 misho 7128: **
7129: ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
7130: ** <dd>^This is the number of virtual machine operations executed
7131: ** by the prepared statement if that number is less than or equal
7132: ** to 2147483647. The number of virtual machine operations can be
7133: ** used as a proxy for the total work done by the prepared statement.
7134: ** If the number of virtual machine operations exceeds 2147483647
7135: ** then the value returned by this statement status code is undefined.
7136: ** </dd>
1.2 misho 7137: ** </dl>
7138: */
7139: #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
7140: #define SQLITE_STMTSTATUS_SORT 2
7141: #define SQLITE_STMTSTATUS_AUTOINDEX 3
1.4 misho 7142: #define SQLITE_STMTSTATUS_VM_STEP 4
1.2 misho 7143:
7144: /*
7145: ** CAPI3REF: Custom Page Cache Object
7146: **
7147: ** The sqlite3_pcache type is opaque. It is implemented by
7148: ** the pluggable module. The SQLite core has no knowledge of
7149: ** its size or internal structure and never deals with the
7150: ** sqlite3_pcache object except by holding and passing pointers
7151: ** to the object.
7152: **
7153: ** See [sqlite3_pcache_methods2] for additional information.
7154: */
7155: typedef struct sqlite3_pcache sqlite3_pcache;
7156:
7157: /*
7158: ** CAPI3REF: Custom Page Cache Object
7159: **
7160: ** The sqlite3_pcache_page object represents a single page in the
7161: ** page cache. The page cache will allocate instances of this
7162: ** object. Various methods of the page cache use pointers to instances
7163: ** of this object as parameters or as their return value.
7164: **
7165: ** See [sqlite3_pcache_methods2] for additional information.
7166: */
7167: typedef struct sqlite3_pcache_page sqlite3_pcache_page;
7168: struct sqlite3_pcache_page {
7169: void *pBuf; /* The content of the page */
7170: void *pExtra; /* Extra information associated with the page */
7171: };
7172:
7173: /*
7174: ** CAPI3REF: Application Defined Page Cache.
7175: ** KEYWORDS: {page cache}
7176: **
7177: ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
7178: ** register an alternative page cache implementation by passing in an
7179: ** instance of the sqlite3_pcache_methods2 structure.)^
7180: ** In many applications, most of the heap memory allocated by
7181: ** SQLite is used for the page cache.
7182: ** By implementing a
7183: ** custom page cache using this API, an application can better control
7184: ** the amount of memory consumed by SQLite, the way in which
7185: ** that memory is allocated and released, and the policies used to
7186: ** determine exactly which parts of a database file are cached and for
7187: ** how long.
7188: **
7189: ** The alternative page cache mechanism is an
7190: ** extreme measure that is only needed by the most demanding applications.
7191: ** The built-in page cache is recommended for most uses.
7192: **
7193: ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
7194: ** internal buffer by SQLite within the call to [sqlite3_config]. Hence
7195: ** the application may discard the parameter after the call to
7196: ** [sqlite3_config()] returns.)^
7197: **
7198: ** [[the xInit() page cache method]]
7199: ** ^(The xInit() method is called once for each effective
7200: ** call to [sqlite3_initialize()])^
7201: ** (usually only once during the lifetime of the process). ^(The xInit()
7202: ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
7203: ** The intent of the xInit() method is to set up global data structures
7204: ** required by the custom page cache implementation.
7205: ** ^(If the xInit() method is NULL, then the
7206: ** built-in default page cache is used instead of the application defined
7207: ** page cache.)^
7208: **
7209: ** [[the xShutdown() page cache method]]
7210: ** ^The xShutdown() method is called by [sqlite3_shutdown()].
7211: ** It can be used to clean up
7212: ** any outstanding resources before process shutdown, if required.
7213: ** ^The xShutdown() method may be NULL.
7214: **
7215: ** ^SQLite automatically serializes calls to the xInit method,
7216: ** so the xInit method need not be threadsafe. ^The
7217: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
7218: ** not need to be threadsafe either. All other methods must be threadsafe
7219: ** in multithreaded applications.
7220: **
7221: ** ^SQLite will never invoke xInit() more than once without an intervening
7222: ** call to xShutdown().
7223: **
7224: ** [[the xCreate() page cache methods]]
7225: ** ^SQLite invokes the xCreate() method to construct a new cache instance.
7226: ** SQLite will typically create one cache instance for each open database file,
7227: ** though this is not guaranteed. ^The
7228: ** first parameter, szPage, is the size in bytes of the pages that must
7229: ** be allocated by the cache. ^szPage will always a power of two. ^The
7230: ** second parameter szExtra is a number of bytes of extra storage
7231: ** associated with each page cache entry. ^The szExtra parameter will
7232: ** a number less than 250. SQLite will use the
7233: ** extra szExtra bytes on each page to store metadata about the underlying
7234: ** database page on disk. The value passed into szExtra depends
7235: ** on the SQLite version, the target platform, and how SQLite was compiled.
7236: ** ^The third argument to xCreate(), bPurgeable, is true if the cache being
7237: ** created will be used to cache database pages of a file stored on disk, or
7238: ** false if it is used for an in-memory database. The cache implementation
7239: ** does not have to do anything special based with the value of bPurgeable;
7240: ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
7241: ** never invoke xUnpin() except to deliberately delete a page.
7242: ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
7243: ** false will always have the "discard" flag set to true.
7244: ** ^Hence, a cache created with bPurgeable false will
7245: ** never contain any unpinned pages.
7246: **
7247: ** [[the xCachesize() page cache method]]
7248: ** ^(The xCachesize() method may be called at any time by SQLite to set the
7249: ** suggested maximum cache-size (number of pages stored by) the cache
7250: ** instance passed as the first argument. This is the value configured using
7251: ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
7252: ** parameter, the implementation is not required to do anything with this
7253: ** value; it is advisory only.
7254: **
7255: ** [[the xPagecount() page cache methods]]
7256: ** The xPagecount() method must return the number of pages currently
7257: ** stored in the cache, both pinned and unpinned.
7258: **
7259: ** [[the xFetch() page cache methods]]
7260: ** The xFetch() method locates a page in the cache and returns a pointer to
7261: ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
7262: ** The pBuf element of the returned sqlite3_pcache_page object will be a
7263: ** pointer to a buffer of szPage bytes used to store the content of a
7264: ** single database page. The pExtra element of sqlite3_pcache_page will be
7265: ** a pointer to the szExtra bytes of extra storage that SQLite has requested
7266: ** for each entry in the page cache.
7267: **
7268: ** The page to be fetched is determined by the key. ^The minimum key value
7269: ** is 1. After it has been retrieved using xFetch, the page is considered
7270: ** to be "pinned".
7271: **
7272: ** If the requested page is already in the page cache, then the page cache
7273: ** implementation must return a pointer to the page buffer with its content
7274: ** intact. If the requested page is not already in the cache, then the
7275: ** cache implementation should use the value of the createFlag
7276: ** parameter to help it determined what action to take:
7277: **
7278: ** <table border=1 width=85% align=center>
1.4 misho 7279: ** <tr><th> createFlag <th> Behavior when page is not already in cache
1.2 misho 7280: ** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
7281: ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
7282: ** Otherwise return NULL.
7283: ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
7284: ** NULL if allocating a new page is effectively impossible.
7285: ** </table>
7286: **
7287: ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
7288: ** will only use a createFlag of 2 after a prior call with a createFlag of 1
7289: ** failed.)^ In between the to xFetch() calls, SQLite may
7290: ** attempt to unpin one or more cache pages by spilling the content of
7291: ** pinned pages to disk and synching the operating system disk cache.
7292: **
7293: ** [[the xUnpin() page cache method]]
7294: ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
7295: ** as its second argument. If the third parameter, discard, is non-zero,
7296: ** then the page must be evicted from the cache.
7297: ** ^If the discard parameter is
7298: ** zero, then the page may be discarded or retained at the discretion of
7299: ** page cache implementation. ^The page cache implementation
7300: ** may choose to evict unpinned pages at any time.
7301: **
7302: ** The cache must not perform any reference counting. A single
7303: ** call to xUnpin() unpins the page regardless of the number of prior calls
7304: ** to xFetch().
7305: **
7306: ** [[the xRekey() page cache methods]]
7307: ** The xRekey() method is used to change the key value associated with the
7308: ** page passed as the second argument. If the cache
7309: ** previously contains an entry associated with newKey, it must be
7310: ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
7311: ** to be pinned.
7312: **
7313: ** When SQLite calls the xTruncate() method, the cache must discard all
7314: ** existing cache entries with page numbers (keys) greater than or equal
7315: ** to the value of the iLimit parameter passed to xTruncate(). If any
7316: ** of these pages are pinned, they are implicitly unpinned, meaning that
7317: ** they can be safely discarded.
7318: **
7319: ** [[the xDestroy() page cache method]]
7320: ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
7321: ** All resources associated with the specified cache should be freed. ^After
7322: ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
7323: ** handle invalid, and will not use it with any other sqlite3_pcache_methods2
7324: ** functions.
7325: **
7326: ** [[the xShrink() page cache method]]
7327: ** ^SQLite invokes the xShrink() method when it wants the page cache to
7328: ** free up as much of heap memory as possible. The page cache implementation
7329: ** is not obligated to free any memory, but well-behaved implementations should
7330: ** do their best.
7331: */
7332: typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
7333: struct sqlite3_pcache_methods2 {
7334: int iVersion;
7335: void *pArg;
7336: int (*xInit)(void*);
7337: void (*xShutdown)(void*);
7338: sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
7339: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
7340: int (*xPagecount)(sqlite3_pcache*);
7341: sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
7342: void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
7343: void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
7344: unsigned oldKey, unsigned newKey);
7345: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
7346: void (*xDestroy)(sqlite3_pcache*);
7347: void (*xShrink)(sqlite3_pcache*);
7348: };
7349:
7350: /*
7351: ** This is the obsolete pcache_methods object that has now been replaced
7352: ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
7353: ** retained in the header file for backwards compatibility only.
7354: */
7355: typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
7356: struct sqlite3_pcache_methods {
7357: void *pArg;
7358: int (*xInit)(void*);
7359: void (*xShutdown)(void*);
7360: sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
7361: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
7362: int (*xPagecount)(sqlite3_pcache*);
7363: void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
7364: void (*xUnpin)(sqlite3_pcache*, void*, int discard);
7365: void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
7366: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
7367: void (*xDestroy)(sqlite3_pcache*);
7368: };
7369:
7370:
7371: /*
7372: ** CAPI3REF: Online Backup Object
7373: **
7374: ** The sqlite3_backup object records state information about an ongoing
7375: ** online backup operation. ^The sqlite3_backup object is created by
7376: ** a call to [sqlite3_backup_init()] and is destroyed by a call to
7377: ** [sqlite3_backup_finish()].
7378: **
7379: ** See Also: [Using the SQLite Online Backup API]
7380: */
7381: typedef struct sqlite3_backup sqlite3_backup;
7382:
7383: /*
7384: ** CAPI3REF: Online Backup API.
7385: **
7386: ** The backup API copies the content of one database into another.
7387: ** It is useful either for creating backups of databases or
7388: ** for copying in-memory databases to or from persistent files.
7389: **
7390: ** See Also: [Using the SQLite Online Backup API]
7391: **
7392: ** ^SQLite holds a write transaction open on the destination database file
7393: ** for the duration of the backup operation.
7394: ** ^The source database is read-locked only while it is being read;
7395: ** it is not locked continuously for the entire backup operation.
7396: ** ^Thus, the backup may be performed on a live source database without
7397: ** preventing other database connections from
7398: ** reading or writing to the source database while the backup is underway.
7399: **
7400: ** ^(To perform a backup operation:
7401: ** <ol>
7402: ** <li><b>sqlite3_backup_init()</b> is called once to initialize the
7403: ** backup,
7404: ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
7405: ** the data between the two databases, and finally
7406: ** <li><b>sqlite3_backup_finish()</b> is called to release all resources
7407: ** associated with the backup operation.
7408: ** </ol>)^
7409: ** There should be exactly one call to sqlite3_backup_finish() for each
7410: ** successful call to sqlite3_backup_init().
7411: **
7412: ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
7413: **
7414: ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
7415: ** [database connection] associated with the destination database
7416: ** and the database name, respectively.
7417: ** ^The database name is "main" for the main database, "temp" for the
7418: ** temporary database, or the name specified after the AS keyword in
7419: ** an [ATTACH] statement for an attached database.
7420: ** ^The S and M arguments passed to
7421: ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
7422: ** and database name of the source database, respectively.
7423: ** ^The source and destination [database connections] (parameters S and D)
7424: ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
7425: ** an error.
7426: **
1.4 misho 7427: ** ^A call to sqlite3_backup_init() will fail, returning NULL, if
7428: ** there is already a read or read-write transaction open on the
7429: ** destination database.
7430: **
1.2 misho 7431: ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
7432: ** returned and an error code and error message are stored in the
7433: ** destination [database connection] D.
7434: ** ^The error code and message for the failed call to sqlite3_backup_init()
7435: ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
7436: ** [sqlite3_errmsg16()] functions.
7437: ** ^A successful call to sqlite3_backup_init() returns a pointer to an
7438: ** [sqlite3_backup] object.
7439: ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
7440: ** sqlite3_backup_finish() functions to perform the specified backup
7441: ** operation.
7442: **
7443: ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
7444: **
7445: ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
7446: ** the source and destination databases specified by [sqlite3_backup] object B.
7447: ** ^If N is negative, all remaining source pages are copied.
7448: ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
7449: ** are still more pages to be copied, then the function returns [SQLITE_OK].
7450: ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
7451: ** from source to destination, then it returns [SQLITE_DONE].
7452: ** ^If an error occurs while running sqlite3_backup_step(B,N),
7453: ** then an [error code] is returned. ^As well as [SQLITE_OK] and
7454: ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
7455: ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
7456: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
7457: **
7458: ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
7459: ** <ol>
7460: ** <li> the destination database was opened read-only, or
7461: ** <li> the destination database is using write-ahead-log journaling
7462: ** and the destination and source page sizes differ, or
7463: ** <li> the destination database is an in-memory database and the
7464: ** destination and source page sizes differ.
7465: ** </ol>)^
7466: **
7467: ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
7468: ** the [sqlite3_busy_handler | busy-handler function]
7469: ** is invoked (if one is specified). ^If the
7470: ** busy-handler returns non-zero before the lock is available, then
7471: ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
7472: ** sqlite3_backup_step() can be retried later. ^If the source
7473: ** [database connection]
7474: ** is being used to write to the source database when sqlite3_backup_step()
7475: ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
7476: ** case the call to sqlite3_backup_step() can be retried later on. ^(If
7477: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
7478: ** [SQLITE_READONLY] is returned, then
7479: ** there is no point in retrying the call to sqlite3_backup_step(). These
7480: ** errors are considered fatal.)^ The application must accept
7481: ** that the backup operation has failed and pass the backup operation handle
7482: ** to the sqlite3_backup_finish() to release associated resources.
7483: **
7484: ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
7485: ** on the destination file. ^The exclusive lock is not released until either
7486: ** sqlite3_backup_finish() is called or the backup operation is complete
7487: ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
7488: ** sqlite3_backup_step() obtains a [shared lock] on the source database that
7489: ** lasts for the duration of the sqlite3_backup_step() call.
7490: ** ^Because the source database is not locked between calls to
7491: ** sqlite3_backup_step(), the source database may be modified mid-way
7492: ** through the backup process. ^If the source database is modified by an
7493: ** external process or via a database connection other than the one being
7494: ** used by the backup operation, then the backup will be automatically
7495: ** restarted by the next call to sqlite3_backup_step(). ^If the source
7496: ** database is modified by the using the same database connection as is used
7497: ** by the backup operation, then the backup database is automatically
7498: ** updated at the same time.
7499: **
7500: ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
7501: **
7502: ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
7503: ** application wishes to abandon the backup operation, the application
7504: ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
7505: ** ^The sqlite3_backup_finish() interfaces releases all
7506: ** resources associated with the [sqlite3_backup] object.
7507: ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
7508: ** active write-transaction on the destination database is rolled back.
7509: ** The [sqlite3_backup] object is invalid
7510: ** and may not be used following a call to sqlite3_backup_finish().
7511: **
7512: ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
7513: ** sqlite3_backup_step() errors occurred, regardless or whether or not
7514: ** sqlite3_backup_step() completed.
7515: ** ^If an out-of-memory condition or IO error occurred during any prior
7516: ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
7517: ** sqlite3_backup_finish() returns the corresponding [error code].
7518: **
7519: ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
7520: ** is not a permanent error and does not affect the return value of
7521: ** sqlite3_backup_finish().
7522: **
1.4 misho 7523: ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
1.2 misho 7524: ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
7525: **
1.4 misho 7526: ** ^The sqlite3_backup_remaining() routine returns the number of pages still
7527: ** to be backed up at the conclusion of the most recent sqlite3_backup_step().
7528: ** ^The sqlite3_backup_pagecount() routine returns the total number of pages
7529: ** in the source database at the conclusion of the most recent
7530: ** sqlite3_backup_step().
7531: ** ^(The values returned by these functions are only updated by
7532: ** sqlite3_backup_step(). If the source database is modified in a way that
7533: ** changes the size of the source database or the number of pages remaining,
7534: ** those changes are not reflected in the output of sqlite3_backup_pagecount()
7535: ** and sqlite3_backup_remaining() until after the next
7536: ** sqlite3_backup_step().)^
1.2 misho 7537: **
7538: ** <b>Concurrent Usage of Database Handles</b>
7539: **
7540: ** ^The source [database connection] may be used by the application for other
7541: ** purposes while a backup operation is underway or being initialized.
7542: ** ^If SQLite is compiled and configured to support threadsafe database
7543: ** connections, then the source database connection may be used concurrently
7544: ** from within other threads.
7545: **
7546: ** However, the application must guarantee that the destination
7547: ** [database connection] is not passed to any other API (by any thread) after
7548: ** sqlite3_backup_init() is called and before the corresponding call to
7549: ** sqlite3_backup_finish(). SQLite does not currently check to see
7550: ** if the application incorrectly accesses the destination [database connection]
7551: ** and so no error code is reported, but the operations may malfunction
7552: ** nevertheless. Use of the destination database connection while a
7553: ** backup is in progress might also also cause a mutex deadlock.
7554: **
7555: ** If running in [shared cache mode], the application must
7556: ** guarantee that the shared cache used by the destination database
7557: ** is not accessed while the backup is running. In practice this means
7558: ** that the application must guarantee that the disk file being
7559: ** backed up to is not accessed by any connection within the process,
7560: ** not just the specific connection that was passed to sqlite3_backup_init().
7561: **
7562: ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
7563: ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
7564: ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
7565: ** APIs are not strictly speaking threadsafe. If they are invoked at the
7566: ** same time as another thread is invoking sqlite3_backup_step() it is
7567: ** possible that they return invalid values.
7568: */
7569: SQLITE_API sqlite3_backup *sqlite3_backup_init(
7570: sqlite3 *pDest, /* Destination database handle */
7571: const char *zDestName, /* Destination database name */
7572: sqlite3 *pSource, /* Source database handle */
7573: const char *zSourceName /* Source database name */
7574: );
7575: SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
7576: SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
7577: SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
7578: SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
7579:
7580: /*
7581: ** CAPI3REF: Unlock Notification
1.4 misho 7582: ** METHOD: sqlite3
1.2 misho 7583: **
7584: ** ^When running in shared-cache mode, a database operation may fail with
7585: ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
7586: ** individual tables within the shared-cache cannot be obtained. See
7587: ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
7588: ** ^This API may be used to register a callback that SQLite will invoke
7589: ** when the connection currently holding the required lock relinquishes it.
7590: ** ^This API is only available if the library was compiled with the
7591: ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
7592: **
7593: ** See Also: [Using the SQLite Unlock Notification Feature].
7594: **
7595: ** ^Shared-cache locks are released when a database connection concludes
7596: ** its current transaction, either by committing it or rolling it back.
7597: **
7598: ** ^When a connection (known as the blocked connection) fails to obtain a
7599: ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
7600: ** identity of the database connection (the blocking connection) that
7601: ** has locked the required resource is stored internally. ^After an
7602: ** application receives an SQLITE_LOCKED error, it may call the
7603: ** sqlite3_unlock_notify() method with the blocked connection handle as
7604: ** the first argument to register for a callback that will be invoked
7605: ** when the blocking connections current transaction is concluded. ^The
7606: ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
7607: ** call that concludes the blocking connections transaction.
7608: **
7609: ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
7610: ** there is a chance that the blocking connection will have already
7611: ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
7612: ** If this happens, then the specified callback is invoked immediately,
7613: ** from within the call to sqlite3_unlock_notify().)^
7614: **
7615: ** ^If the blocked connection is attempting to obtain a write-lock on a
7616: ** shared-cache table, and more than one other connection currently holds
7617: ** a read-lock on the same table, then SQLite arbitrarily selects one of
7618: ** the other connections to use as the blocking connection.
7619: **
7620: ** ^(There may be at most one unlock-notify callback registered by a
7621: ** blocked connection. If sqlite3_unlock_notify() is called when the
7622: ** blocked connection already has a registered unlock-notify callback,
7623: ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
7624: ** called with a NULL pointer as its second argument, then any existing
7625: ** unlock-notify callback is canceled. ^The blocked connections
7626: ** unlock-notify callback may also be canceled by closing the blocked
7627: ** connection using [sqlite3_close()].
7628: **
7629: ** The unlock-notify callback is not reentrant. If an application invokes
7630: ** any sqlite3_xxx API functions from within an unlock-notify callback, a
7631: ** crash or deadlock may be the result.
7632: **
7633: ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
7634: ** returns SQLITE_OK.
7635: **
7636: ** <b>Callback Invocation Details</b>
7637: **
7638: ** When an unlock-notify callback is registered, the application provides a
7639: ** single void* pointer that is passed to the callback when it is invoked.
7640: ** However, the signature of the callback function allows SQLite to pass
7641: ** it an array of void* context pointers. The first argument passed to
7642: ** an unlock-notify callback is a pointer to an array of void* pointers,
7643: ** and the second is the number of entries in the array.
7644: **
7645: ** When a blocking connections transaction is concluded, there may be
7646: ** more than one blocked connection that has registered for an unlock-notify
7647: ** callback. ^If two or more such blocked connections have specified the
7648: ** same callback function, then instead of invoking the callback function
7649: ** multiple times, it is invoked once with the set of void* context pointers
7650: ** specified by the blocked connections bundled together into an array.
7651: ** This gives the application an opportunity to prioritize any actions
7652: ** related to the set of unblocked database connections.
7653: **
7654: ** <b>Deadlock Detection</b>
7655: **
7656: ** Assuming that after registering for an unlock-notify callback a
7657: ** database waits for the callback to be issued before taking any further
7658: ** action (a reasonable assumption), then using this API may cause the
7659: ** application to deadlock. For example, if connection X is waiting for
7660: ** connection Y's transaction to be concluded, and similarly connection
7661: ** Y is waiting on connection X's transaction, then neither connection
7662: ** will proceed and the system may remain deadlocked indefinitely.
7663: **
7664: ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
7665: ** detection. ^If a given call to sqlite3_unlock_notify() would put the
7666: ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
7667: ** unlock-notify callback is registered. The system is said to be in
7668: ** a deadlocked state if connection A has registered for an unlock-notify
7669: ** callback on the conclusion of connection B's transaction, and connection
7670: ** B has itself registered for an unlock-notify callback when connection
7671: ** A's transaction is concluded. ^Indirect deadlock is also detected, so
7672: ** the system is also considered to be deadlocked if connection B has
7673: ** registered for an unlock-notify callback on the conclusion of connection
7674: ** C's transaction, where connection C is waiting on connection A. ^Any
7675: ** number of levels of indirection are allowed.
7676: **
7677: ** <b>The "DROP TABLE" Exception</b>
7678: **
7679: ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
7680: ** always appropriate to call sqlite3_unlock_notify(). There is however,
7681: ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
7682: ** SQLite checks if there are any currently executing SELECT statements
7683: ** that belong to the same connection. If there are, SQLITE_LOCKED is
7684: ** returned. In this case there is no "blocking connection", so invoking
7685: ** sqlite3_unlock_notify() results in the unlock-notify callback being
7686: ** invoked immediately. If the application then re-attempts the "DROP TABLE"
7687: ** or "DROP INDEX" query, an infinite loop might be the result.
7688: **
7689: ** One way around this problem is to check the extended error code returned
7690: ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
7691: ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
7692: ** the special "DROP TABLE/INDEX" case, the extended error code is just
7693: ** SQLITE_LOCKED.)^
7694: */
7695: SQLITE_API int sqlite3_unlock_notify(
7696: sqlite3 *pBlocked, /* Waiting connection */
7697: void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
7698: void *pNotifyArg /* Argument to pass to xNotify */
7699: );
7700:
7701:
7702: /*
7703: ** CAPI3REF: String Comparison
7704: **
1.3 misho 7705: ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
7706: ** and extensions to compare the contents of two buffers containing UTF-8
7707: ** strings in a case-independent fashion, using the same definition of "case
7708: ** independence" that SQLite uses internally when comparing identifiers.
1.2 misho 7709: */
1.3 misho 7710: SQLITE_API int sqlite3_stricmp(const char *, const char *);
1.2 misho 7711: SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
7712:
7713: /*
1.4 misho 7714: ** CAPI3REF: String Globbing
7715: *
7716: ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
7717: ** string X matches the [GLOB] pattern P.
7718: ** ^The definition of [GLOB] pattern matching used in
7719: ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
7720: ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function
7721: ** is case sensitive.
7722: **
7723: ** Note that this routine returns zero on a match and non-zero if the strings
7724: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
7725: **
7726: ** See also: [sqlite3_strlike()].
7727: */
7728: SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
7729:
7730: /*
7731: ** CAPI3REF: String LIKE Matching
7732: *
7733: ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
7734: ** string X matches the [LIKE] pattern P with escape character E.
7735: ** ^The definition of [LIKE] pattern matching used in
7736: ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
7737: ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without
7738: ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
7739: ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
7740: ** insensitive - equivalent upper and lower case ASCII characters match
7741: ** one another.
7742: **
7743: ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
7744: ** only ASCII characters are case folded.
7745: **
7746: ** Note that this routine returns zero on a match and non-zero if the strings
7747: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
7748: **
7749: ** See also: [sqlite3_strglob()].
7750: */
7751: SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
7752:
7753: /*
1.2 misho 7754: ** CAPI3REF: Error Logging Interface
7755: **
1.4 misho 7756: ** ^The [sqlite3_log()] interface writes a message into the [error log]
1.2 misho 7757: ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
7758: ** ^If logging is enabled, the zFormat string and subsequent arguments are
7759: ** used with [sqlite3_snprintf()] to generate the final output string.
7760: **
7761: ** The sqlite3_log() interface is intended for use by extensions such as
7762: ** virtual tables, collating functions, and SQL functions. While there is
7763: ** nothing to prevent an application from calling sqlite3_log(), doing so
7764: ** is considered bad form.
7765: **
7766: ** The zFormat string must not be NULL.
7767: **
7768: ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
7769: ** will not use dynamically allocated memory. The log message is stored in
7770: ** a fixed-length buffer on the stack. If the log message is longer than
7771: ** a few hundred characters, it will be truncated to the length of the
7772: ** buffer.
7773: */
7774: SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
7775:
7776: /*
7777: ** CAPI3REF: Write-Ahead Log Commit Hook
1.4 misho 7778: ** METHOD: sqlite3
1.2 misho 7779: **
7780: ** ^The [sqlite3_wal_hook()] function is used to register a callback that
1.4 misho 7781: ** is invoked each time data is committed to a database in wal mode.
1.2 misho 7782: **
1.4 misho 7783: ** ^(The callback is invoked by SQLite after the commit has taken place and
7784: ** the associated write-lock on the database released)^, so the implementation
1.2 misho 7785: ** may read, write or [checkpoint] the database as required.
7786: **
7787: ** ^The first parameter passed to the callback function when it is invoked
7788: ** is a copy of the third parameter passed to sqlite3_wal_hook() when
7789: ** registering the callback. ^The second is a copy of the database handle.
7790: ** ^The third parameter is the name of the database that was written to -
7791: ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
7792: ** is the number of pages currently in the write-ahead log file,
7793: ** including those that were just committed.
7794: **
7795: ** The callback function should normally return [SQLITE_OK]. ^If an error
7796: ** code is returned, that error will propagate back up through the
7797: ** SQLite code base to cause the statement that provoked the callback
7798: ** to report an error, though the commit will have still occurred. If the
7799: ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
7800: ** that does not correspond to any valid SQLite error code, the results
7801: ** are undefined.
7802: **
7803: ** A single database handle may have at most a single write-ahead log callback
7804: ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
7805: ** previously registered write-ahead log callback. ^Note that the
7806: ** [sqlite3_wal_autocheckpoint()] interface and the
7807: ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
1.4 misho 7808: ** overwrite any prior [sqlite3_wal_hook()] settings.
1.2 misho 7809: */
7810: SQLITE_API void *sqlite3_wal_hook(
7811: sqlite3*,
7812: int(*)(void *,sqlite3*,const char*,int),
7813: void*
7814: );
7815:
7816: /*
7817: ** CAPI3REF: Configure an auto-checkpoint
1.4 misho 7818: ** METHOD: sqlite3
1.2 misho 7819: **
7820: ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
7821: ** [sqlite3_wal_hook()] that causes any database on [database connection] D
7822: ** to automatically [checkpoint]
7823: ** after committing a transaction if there are N or
7824: ** more frames in the [write-ahead log] file. ^Passing zero or
7825: ** a negative value as the nFrame parameter disables automatic
7826: ** checkpoints entirely.
7827: **
7828: ** ^The callback registered by this function replaces any existing callback
7829: ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
7830: ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
7831: ** configured by this function.
7832: **
7833: ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
7834: ** from SQL.
7835: **
1.4 misho 7836: ** ^Checkpoints initiated by this mechanism are
7837: ** [sqlite3_wal_checkpoint_v2|PASSIVE].
7838: **
1.2 misho 7839: ** ^Every new [database connection] defaults to having the auto-checkpoint
7840: ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
7841: ** pages. The use of this interface
7842: ** is only necessary if the default setting is found to be suboptimal
7843: ** for a particular application.
7844: */
7845: SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
7846:
7847: /*
7848: ** CAPI3REF: Checkpoint a database
1.4 misho 7849: ** METHOD: sqlite3
1.2 misho 7850: **
1.4 misho 7851: ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
7852: ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
1.2 misho 7853: **
1.4 misho 7854: ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
7855: ** [write-ahead log] for database X on [database connection] D to be
7856: ** transferred into the database file and for the write-ahead log to
7857: ** be reset. See the [checkpointing] documentation for addition
7858: ** information.
7859: **
7860: ** This interface used to be the only way to cause a checkpoint to
7861: ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
7862: ** interface was added. This interface is retained for backwards
7863: ** compatibility and as a convenience for applications that need to manually
7864: ** start a callback but which do not need the full power (and corresponding
7865: ** complication) of [sqlite3_wal_checkpoint_v2()].
1.2 misho 7866: */
7867: SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
7868:
7869: /*
7870: ** CAPI3REF: Checkpoint a database
1.4 misho 7871: ** METHOD: sqlite3
1.2 misho 7872: **
1.4 misho 7873: ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
7874: ** operation on database X of [database connection] D in mode M. Status
7875: ** information is written back into integers pointed to by L and C.)^
7876: ** ^(The M parameter must be a valid [checkpoint mode]:)^
1.2 misho 7877: **
7878: ** <dl>
7879: ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
1.4 misho 7880: ** ^Checkpoint as many frames as possible without waiting for any database
7881: ** readers or writers to finish, then sync the database file if all frames
7882: ** in the log were checkpointed. ^The [busy-handler callback]
7883: ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
7884: ** ^On the other hand, passive mode might leave the checkpoint unfinished
7885: ** if there are concurrent readers or writers.
1.2 misho 7886: **
7887: ** <dt>SQLITE_CHECKPOINT_FULL<dd>
1.4 misho 7888: ** ^This mode blocks (it invokes the
7889: ** [sqlite3_busy_handler|busy-handler callback]) until there is no
1.2 misho 7890: ** database writer and all readers are reading from the most recent database
1.4 misho 7891: ** snapshot. ^It then checkpoints all frames in the log file and syncs the
7892: ** database file. ^This mode blocks new database writers while it is pending,
7893: ** but new database readers are allowed to continue unimpeded.
1.2 misho 7894: **
7895: ** <dt>SQLITE_CHECKPOINT_RESTART<dd>
1.4 misho 7896: ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
7897: ** that after checkpointing the log file it blocks (calls the
7898: ** [busy-handler callback])
7899: ** until all readers are reading from the database file only. ^This ensures
7900: ** that the next writer will restart the log file from the beginning.
7901: ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
7902: ** database writer attempts while it is pending, but does not impede readers.
7903: **
7904: ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
7905: ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
7906: ** addition that it also truncates the log file to zero bytes just prior
7907: ** to a successful return.
1.2 misho 7908: ** </dl>
7909: **
1.4 misho 7910: ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
7911: ** the log file or to -1 if the checkpoint could not run because
7912: ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
7913: ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
7914: ** log file (including any that were already checkpointed before the function
7915: ** was called) or to -1 if the checkpoint could not run due to an error or
7916: ** because the database is not in WAL mode. ^Note that upon successful
7917: ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
7918: ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
1.2 misho 7919: **
1.4 misho 7920: ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
1.2 misho 7921: ** any other process is running a checkpoint operation at the same time, the
1.4 misho 7922: ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
1.2 misho 7923: ** busy-handler configured, it will not be invoked in this case.
7924: **
1.4 misho 7925: ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
7926: ** exclusive "writer" lock on the database file. ^If the writer lock cannot be
7927: ** obtained immediately, and a busy-handler is configured, it is invoked and
7928: ** the writer lock retried until either the busy-handler returns 0 or the lock
7929: ** is successfully obtained. ^The busy-handler is also invoked while waiting for
7930: ** database readers as described above. ^If the busy-handler returns 0 before
1.2 misho 7931: ** the writer lock is obtained or while waiting for database readers, the
7932: ** checkpoint operation proceeds from that point in the same way as
7933: ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
1.4 misho 7934: ** without blocking any further. ^SQLITE_BUSY is returned in this case.
1.2 misho 7935: **
1.4 misho 7936: ** ^If parameter zDb is NULL or points to a zero length string, then the
7937: ** specified operation is attempted on all WAL databases [attached] to
7938: ** [database connection] db. In this case the
7939: ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
1.2 misho 7940: ** an SQLITE_BUSY error is encountered when processing one or more of the
7941: ** attached WAL databases, the operation is still attempted on any remaining
1.4 misho 7942: ** attached databases and SQLITE_BUSY is returned at the end. ^If any other
1.2 misho 7943: ** error occurs while processing an attached database, processing is abandoned
1.4 misho 7944: ** and the error code is returned to the caller immediately. ^If no error
1.2 misho 7945: ** (SQLITE_BUSY or otherwise) is encountered while processing the attached
7946: ** databases, SQLITE_OK is returned.
7947: **
1.4 misho 7948: ** ^If database zDb is the name of an attached database that is not in WAL
7949: ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
1.2 misho 7950: ** zDb is not NULL (or a zero length string) and is not the name of any
7951: ** attached database, SQLITE_ERROR is returned to the caller.
1.4 misho 7952: **
7953: ** ^Unless it returns SQLITE_MISUSE,
7954: ** the sqlite3_wal_checkpoint_v2() interface
7955: ** sets the error information that is queried by
7956: ** [sqlite3_errcode()] and [sqlite3_errmsg()].
7957: **
7958: ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
7959: ** from SQL.
1.2 misho 7960: */
7961: SQLITE_API int sqlite3_wal_checkpoint_v2(
7962: sqlite3 *db, /* Database handle */
7963: const char *zDb, /* Name of attached database (or NULL) */
7964: int eMode, /* SQLITE_CHECKPOINT_* value */
7965: int *pnLog, /* OUT: Size of WAL log in frames */
7966: int *pnCkpt /* OUT: Total number of frames checkpointed */
7967: );
7968:
7969: /*
1.4 misho 7970: ** CAPI3REF: Checkpoint Mode Values
7971: ** KEYWORDS: {checkpoint mode}
1.2 misho 7972: **
1.4 misho 7973: ** These constants define all valid values for the "checkpoint mode" passed
7974: ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
7975: ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
7976: ** meaning of each of these checkpoint modes.
7977: */
7978: #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */
7979: #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */
7980: #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */
7981: #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */
1.2 misho 7982:
7983: /*
7984: ** CAPI3REF: Virtual Table Interface Configuration
7985: **
7986: ** This function may be called by either the [xConnect] or [xCreate] method
7987: ** of a [virtual table] implementation to configure
7988: ** various facets of the virtual table interface.
7989: **
7990: ** If this interface is invoked outside the context of an xConnect or
7991: ** xCreate virtual table method then the behavior is undefined.
7992: **
7993: ** At present, there is only one option that may be configured using
7994: ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
7995: ** may be added in the future.
7996: */
7997: SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
7998:
7999: /*
8000: ** CAPI3REF: Virtual Table Configuration Options
8001: **
8002: ** These macros define the various options to the
8003: ** [sqlite3_vtab_config()] interface that [virtual table] implementations
8004: ** can use to customize and optimize their behavior.
8005: **
8006: ** <dl>
8007: ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
8008: ** <dd>Calls of the form
8009: ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
8010: ** where X is an integer. If X is zero, then the [virtual table] whose
8011: ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
8012: ** support constraints. In this configuration (which is the default) if
8013: ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
8014: ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
8015: ** specified as part of the users SQL statement, regardless of the actual
8016: ** ON CONFLICT mode specified.
8017: **
8018: ** If X is non-zero, then the virtual table implementation guarantees
8019: ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
8020: ** any modifications to internal or persistent data structures have been made.
8021: ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
8022: ** is able to roll back a statement or database transaction, and abandon
8023: ** or continue processing the current SQL statement as appropriate.
8024: ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
8025: ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
8026: ** had been ABORT.
8027: **
8028: ** Virtual table implementations that are required to handle OR REPLACE
8029: ** must do so within the [xUpdate] method. If a call to the
8030: ** [sqlite3_vtab_on_conflict()] function indicates that the current ON
8031: ** CONFLICT policy is REPLACE, the virtual table implementation should
8032: ** silently replace the appropriate rows within the xUpdate callback and
8033: ** return SQLITE_OK. Or, if this is not possible, it may return
8034: ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
8035: ** constraint handling.
8036: ** </dl>
8037: */
8038: #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
8039:
8040: /*
8041: ** CAPI3REF: Determine The Virtual Table Conflict Policy
8042: **
8043: ** This function may only be called from within a call to the [xUpdate] method
8044: ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
8045: ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
8046: ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
8047: ** of the SQL statement that triggered the call to the [xUpdate] method of the
8048: ** [virtual table].
8049: */
8050: SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
8051:
8052: /*
8053: ** CAPI3REF: Conflict resolution modes
1.4 misho 8054: ** KEYWORDS: {conflict resolution mode}
1.2 misho 8055: **
8056: ** These constants are returned by [sqlite3_vtab_on_conflict()] to
8057: ** inform a [virtual table] implementation what the [ON CONFLICT] mode
8058: ** is for the SQL statement being evaluated.
8059: **
8060: ** Note that the [SQLITE_IGNORE] constant is also used as a potential
8061: ** return value from the [sqlite3_set_authorizer()] callback and that
8062: ** [SQLITE_ABORT] is also a [result code].
8063: */
8064: #define SQLITE_ROLLBACK 1
8065: /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
8066: #define SQLITE_FAIL 3
8067: /* #define SQLITE_ABORT 4 // Also an error code */
8068: #define SQLITE_REPLACE 5
8069:
1.4 misho 8070: /*
8071: ** CAPI3REF: Prepared Statement Scan Status Opcodes
8072: ** KEYWORDS: {scanstatus options}
8073: **
8074: ** The following constants can be used for the T parameter to the
8075: ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a
8076: ** different metric for sqlite3_stmt_scanstatus() to return.
8077: **
8078: ** When the value returned to V is a string, space to hold that string is
8079: ** managed by the prepared statement S and will be automatically freed when
8080: ** S is finalized.
8081: **
8082: ** <dl>
8083: ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
8084: ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be
8085: ** set to the total number of times that the X-th loop has run.</dd>
8086: **
8087: ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
8088: ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set
8089: ** to the total number of rows examined by all iterations of the X-th loop.</dd>
8090: **
8091: ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
8092: ** <dd>^The "double" variable pointed to by the T parameter will be set to the
8093: ** query planner's estimate for the average number of rows output from each
8094: ** iteration of the X-th loop. If the query planner's estimates was accurate,
8095: ** then this value will approximate the quotient NVISIT/NLOOP and the
8096: ** product of this value for all prior loops with the same SELECTID will
8097: ** be the NLOOP value for the current loop.
8098: **
8099: ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
8100: ** <dd>^The "const char *" variable pointed to by the T parameter will be set
8101: ** to a zero-terminated UTF-8 string containing the name of the index or table
8102: ** used for the X-th loop.
8103: **
8104: ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
8105: ** <dd>^The "const char *" variable pointed to by the T parameter will be set
8106: ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
8107: ** description for the X-th loop.
8108: **
8109: ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt>
8110: ** <dd>^The "int" variable pointed to by the T parameter will be set to the
8111: ** "select-id" for the X-th loop. The select-id identifies which query or
8112: ** subquery the loop is part of. The main query has a select-id of zero.
8113: ** The select-id is the same value as is output in the first column
8114: ** of an [EXPLAIN QUERY PLAN] query.
8115: ** </dl>
8116: */
8117: #define SQLITE_SCANSTAT_NLOOP 0
8118: #define SQLITE_SCANSTAT_NVISIT 1
8119: #define SQLITE_SCANSTAT_EST 2
8120: #define SQLITE_SCANSTAT_NAME 3
8121: #define SQLITE_SCANSTAT_EXPLAIN 4
8122: #define SQLITE_SCANSTAT_SELECTID 5
8123:
8124: /*
8125: ** CAPI3REF: Prepared Statement Scan Status
8126: ** METHOD: sqlite3_stmt
8127: **
8128: ** This interface returns information about the predicted and measured
8129: ** performance for pStmt. Advanced applications can use this
8130: ** interface to compare the predicted and the measured performance and
8131: ** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
8132: **
8133: ** Since this interface is expected to be rarely used, it is only
8134: ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
8135: ** compile-time option.
8136: **
8137: ** The "iScanStatusOp" parameter determines which status information to return.
8138: ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
8139: ** of this interface is undefined.
8140: ** ^The requested measurement is written into a variable pointed to by
8141: ** the "pOut" parameter.
8142: ** Parameter "idx" identifies the specific loop to retrieve statistics for.
8143: ** Loops are numbered starting from zero. ^If idx is out of range - less than
8144: ** zero or greater than or equal to the total number of loops used to implement
8145: ** the statement - a non-zero value is returned and the variable that pOut
8146: ** points to is unchanged.
8147: **
8148: ** ^Statistics might not be available for all loops in all statements. ^In cases
8149: ** where there exist loops with no available statistics, this function behaves
8150: ** as if the loop did not exist - it returns non-zero and leave the variable
8151: ** that pOut points to unchanged.
8152: **
8153: ** See also: [sqlite3_stmt_scanstatus_reset()]
8154: */
8155: SQLITE_API int sqlite3_stmt_scanstatus(
8156: sqlite3_stmt *pStmt, /* Prepared statement for which info desired */
8157: int idx, /* Index of loop to report on */
8158: int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */
8159: void *pOut /* Result written here */
8160: );
8161:
8162: /*
8163: ** CAPI3REF: Zero Scan-Status Counters
8164: ** METHOD: sqlite3_stmt
8165: **
8166: ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
8167: **
8168: ** This API is only available if the library is built with pre-processor
8169: ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
8170: */
8171: SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
8172:
8173: /*
8174: ** CAPI3REF: Flush caches to disk mid-transaction
8175: **
8176: ** ^If a write-transaction is open on [database connection] D when the
8177: ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
8178: ** pages in the pager-cache that are not currently in use are written out
8179: ** to disk. A dirty page may be in use if a database cursor created by an
8180: ** active SQL statement is reading from it, or if it is page 1 of a database
8181: ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]
8182: ** interface flushes caches for all schemas - "main", "temp", and
8183: ** any [attached] databases.
8184: **
8185: ** ^If this function needs to obtain extra database locks before dirty pages
8186: ** can be flushed to disk, it does so. ^If those locks cannot be obtained
8187: ** immediately and there is a busy-handler callback configured, it is invoked
8188: ** in the usual manner. ^If the required lock still cannot be obtained, then
8189: ** the database is skipped and an attempt made to flush any dirty pages
8190: ** belonging to the next (if any) database. ^If any databases are skipped
8191: ** because locks cannot be obtained, but no other error occurs, this
8192: ** function returns SQLITE_BUSY.
8193: **
8194: ** ^If any other error occurs while flushing dirty pages to disk (for
8195: ** example an IO error or out-of-memory condition), then processing is
8196: ** abandoned and an SQLite [error code] is returned to the caller immediately.
8197: **
8198: ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
8199: **
8200: ** ^This function does not set the database handle error code or message
8201: ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
8202: */
8203: SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
8204:
8205: /*
8206: ** CAPI3REF: The pre-update hook.
8207: **
8208: ** ^These interfaces are only available if SQLite is compiled using the
8209: ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
8210: **
8211: ** ^The [sqlite3_preupdate_hook()] interface registers a callback function
8212: ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
1.4.2.1 ! misho 8213: ** on a database table.
1.4 misho 8214: ** ^At most one preupdate hook may be registered at a time on a single
8215: ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
8216: ** the previous setting.
8217: ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
8218: ** with a NULL pointer as the second parameter.
8219: ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
8220: ** the first parameter to callbacks.
8221: **
1.4.2.1 ! misho 8222: ** ^The preupdate hook only fires for changes to real database tables; the
! 8223: ** preupdate hook is not invoked for changes to [virtual tables] or to
! 8224: ** system tables like sqlite_master or sqlite_stat1.
1.4 misho 8225: **
8226: ** ^The second parameter to the preupdate callback is a pointer to
8227: ** the [database connection] that registered the preupdate hook.
8228: ** ^The third parameter to the preupdate callback is one of the constants
8229: ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
8230: ** kind of update operation that is about to occur.
8231: ** ^(The fourth parameter to the preupdate callback is the name of the
8232: ** database within the database connection that is being modified. This
8233: ** will be "main" for the main database or "temp" for TEMP tables or
8234: ** the name given after the AS keyword in the [ATTACH] statement for attached
8235: ** databases.)^
8236: ** ^The fifth parameter to the preupdate callback is the name of the
8237: ** table that is being modified.
1.4.2.1 ! misho 8238: **
! 8239: ** For an UPDATE or DELETE operation on a [rowid table], the sixth
! 8240: ** parameter passed to the preupdate callback is the initial [rowid] of the
! 8241: ** row being modified or deleted. For an INSERT operation on a rowid table,
! 8242: ** or any operation on a WITHOUT ROWID table, the value of the sixth
! 8243: ** parameter is undefined. For an INSERT or UPDATE on a rowid table the
! 8244: ** seventh parameter is the final rowid value of the row being inserted
! 8245: ** or updated. The value of the seventh parameter passed to the callback
! 8246: ** function is not defined for operations on WITHOUT ROWID tables, or for
! 8247: ** INSERT operations on rowid tables.
1.4 misho 8248: **
8249: ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
8250: ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
8251: ** provide additional information about a preupdate event. These routines
8252: ** may only be called from within a preupdate callback. Invoking any of
8253: ** these routines from outside of a preupdate callback or with a
8254: ** [database connection] pointer that is different from the one supplied
8255: ** to the preupdate callback results in undefined and probably undesirable
8256: ** behavior.
8257: **
8258: ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
8259: ** in the row that is being inserted, updated, or deleted.
8260: **
8261: ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
8262: ** a [protected sqlite3_value] that contains the value of the Nth column of
8263: ** the table row before it is updated. The N parameter must be between 0
8264: ** and one less than the number of columns or the behavior will be
8265: ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
8266: ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
8267: ** behavior is undefined. The [sqlite3_value] that P points to
8268: ** will be destroyed when the preupdate callback returns.
8269: **
8270: ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
8271: ** a [protected sqlite3_value] that contains the value of the Nth column of
8272: ** the table row after it is updated. The N parameter must be between 0
8273: ** and one less than the number of columns or the behavior will be
8274: ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
8275: ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
8276: ** behavior is undefined. The [sqlite3_value] that P points to
8277: ** will be destroyed when the preupdate callback returns.
8278: **
8279: ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
8280: ** callback was invoked as a result of a direct insert, update, or delete
8281: ** operation; or 1 for inserts, updates, or deletes invoked by top-level
8282: ** triggers; or 2 for changes resulting from triggers called by top-level
8283: ** triggers; and so forth.
8284: **
8285: ** See also: [sqlite3_update_hook()]
8286: */
1.4.2.1 ! misho 8287: #if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
! 8288: SQLITE_API void *sqlite3_preupdate_hook(
1.4 misho 8289: sqlite3 *db,
8290: void(*xPreUpdate)(
8291: void *pCtx, /* Copy of third arg to preupdate_hook() */
8292: sqlite3 *db, /* Database handle */
8293: int op, /* SQLITE_UPDATE, DELETE or INSERT */
8294: char const *zDb, /* Database name */
8295: char const *zName, /* Table name */
8296: sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */
8297: sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */
8298: ),
8299: void*
8300: );
1.4.2.1 ! misho 8301: SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
! 8302: SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
! 8303: SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
! 8304: SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
! 8305: #endif
1.4 misho 8306:
8307: /*
8308: ** CAPI3REF: Low-level system error code
8309: **
8310: ** ^Attempt to return the underlying operating system error code or error
8311: ** number that caused the most recent I/O error or failure to open a file.
8312: ** The return value is OS-dependent. For example, on unix systems, after
8313: ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
8314: ** called to get back the underlying "errno" that caused the problem, such
8315: ** as ENOSPC, EAUTH, EISDIR, and so forth.
8316: */
8317: SQLITE_API int sqlite3_system_errno(sqlite3*);
8318:
8319: /*
8320: ** CAPI3REF: Database Snapshot
1.4.2.1 ! misho 8321: ** KEYWORDS: {snapshot} {sqlite3_snapshot}
1.4 misho 8322: ** EXPERIMENTAL
8323: **
8324: ** An instance of the snapshot object records the state of a [WAL mode]
8325: ** database for some specific point in history.
8326: **
8327: ** In [WAL mode], multiple [database connections] that are open on the
8328: ** same database file can each be reading a different historical version
8329: ** of the database file. When a [database connection] begins a read
8330: ** transaction, that connection sees an unchanging copy of the database
8331: ** as it existed for the point in time when the transaction first started.
8332: ** Subsequent changes to the database from other connections are not seen
8333: ** by the reader until a new read transaction is started.
8334: **
8335: ** The sqlite3_snapshot object records state information about an historical
8336: ** version of the database file so that it is possible to later open a new read
8337: ** transaction that sees that historical version of the database rather than
8338: ** the most recent version.
8339: **
8340: ** The constructor for this object is [sqlite3_snapshot_get()]. The
8341: ** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer
8342: ** to an historical snapshot (if possible). The destructor for
8343: ** sqlite3_snapshot objects is [sqlite3_snapshot_free()].
8344: */
1.4.2.1 ! misho 8345: typedef struct sqlite3_snapshot {
! 8346: unsigned char hidden[48];
! 8347: } sqlite3_snapshot;
1.4 misho 8348:
8349: /*
8350: ** CAPI3REF: Record A Database Snapshot
8351: ** EXPERIMENTAL
8352: **
8353: ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
8354: ** new [sqlite3_snapshot] object that records the current state of
8355: ** schema S in database connection D. ^On success, the
8356: ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
8357: ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
1.4.2.1 ! misho 8358: ** If there is not already a read-transaction open on schema S when
! 8359: ** this function is called, one is opened automatically.
! 8360: **
! 8361: ** The following must be true for this function to succeed. If any of
! 8362: ** the following statements are false when sqlite3_snapshot_get() is
! 8363: ** called, SQLITE_ERROR is returned. The final value of *P is undefined
! 8364: ** in this case.
! 8365: **
! 8366: ** <ul>
! 8367: ** <li> The database handle must be in [autocommit mode].
! 8368: **
! 8369: ** <li> Schema S of [database connection] D must be a [WAL mode] database.
! 8370: **
! 8371: ** <li> There must not be a write transaction open on schema S of database
! 8372: ** connection D.
! 8373: **
! 8374: ** <li> One or more transactions must have been written to the current wal
! 8375: ** file since it was created on disk (by any connection). This means
! 8376: ** that a snapshot cannot be taken on a wal mode database with no wal
! 8377: ** file immediately after it is first opened. At least one transaction
! 8378: ** must be written to it first.
! 8379: ** </ul>
! 8380: **
! 8381: ** This function may also return SQLITE_NOMEM. If it is called with the
! 8382: ** database handle in autocommit mode but fails for some other reason,
! 8383: ** whether or not a read transaction is opened on schema S is undefined.
1.4 misho 8384: **
8385: ** The [sqlite3_snapshot] object returned from a successful call to
8386: ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
8387: ** to avoid a memory leak.
8388: **
8389: ** The [sqlite3_snapshot_get()] interface is only available when the
8390: ** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
8391: */
8392: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
8393: sqlite3 *db,
8394: const char *zSchema,
8395: sqlite3_snapshot **ppSnapshot
8396: );
8397:
8398: /*
8399: ** CAPI3REF: Start a read transaction on an historical snapshot
8400: ** EXPERIMENTAL
8401: **
8402: ** ^The [sqlite3_snapshot_open(D,S,P)] interface starts a
8403: ** read transaction for schema S of
8404: ** [database connection] D such that the read transaction
8405: ** refers to historical [snapshot] P, rather than the most
8406: ** recent change to the database.
8407: ** ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK on success
8408: ** or an appropriate [error code] if it fails.
8409: **
8410: ** ^In order to succeed, a call to [sqlite3_snapshot_open(D,S,P)] must be
8411: ** the first operation following the [BEGIN] that takes the schema S
8412: ** out of [autocommit mode].
8413: ** ^In other words, schema S must not currently be in
8414: ** a transaction for [sqlite3_snapshot_open(D,S,P)] to work, but the
8415: ** database connection D must be out of [autocommit mode].
8416: ** ^A [snapshot] will fail to open if it has been overwritten by a
8417: ** [checkpoint].
8418: ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
8419: ** database connection D does not know that the database file for
8420: ** schema S is in [WAL mode]. A database connection might not know
8421: ** that the database file is in [WAL mode] if there has been no prior
8422: ** I/O on that database connection, or if the database entered [WAL mode]
8423: ** after the most recent I/O on the database connection.)^
8424: ** (Hint: Run "[PRAGMA application_id]" against a newly opened
8425: ** database connection in order to make it ready to use snapshots.)
8426: **
8427: ** The [sqlite3_snapshot_open()] interface is only available when the
8428: ** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
8429: */
8430: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
8431: sqlite3 *db,
8432: const char *zSchema,
8433: sqlite3_snapshot *pSnapshot
8434: );
8435:
8436: /*
8437: ** CAPI3REF: Destroy a snapshot
8438: ** EXPERIMENTAL
8439: **
8440: ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
8441: ** The application must eventually free every [sqlite3_snapshot] object
8442: ** using this routine to avoid a memory leak.
8443: **
8444: ** The [sqlite3_snapshot_free()] interface is only available when the
8445: ** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
8446: */
8447: SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
1.2 misho 8448:
1.4 misho 8449: /*
8450: ** CAPI3REF: Compare the ages of two snapshot handles.
8451: ** EXPERIMENTAL
8452: **
8453: ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
8454: ** of two valid snapshot handles.
8455: **
8456: ** If the two snapshot handles are not associated with the same database
8457: ** file, the result of the comparison is undefined.
8458: **
8459: ** Additionally, the result of the comparison is only valid if both of the
8460: ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
8461: ** last time the wal file was deleted. The wal file is deleted when the
8462: ** database is changed back to rollback mode or when the number of database
8463: ** clients drops to zero. If either snapshot handle was obtained before the
8464: ** wal file was last deleted, the value returned by this function
8465: ** is undefined.
8466: **
8467: ** Otherwise, this API returns a negative value if P1 refers to an older
8468: ** snapshot than P2, zero if the two handles refer to the same database
8469: ** snapshot, and a positive value if P1 is a newer snapshot than P2.
8470: */
8471: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
8472: sqlite3_snapshot *p1,
8473: sqlite3_snapshot *p2
8474: );
1.2 misho 8475:
8476: /*
1.4.2.1 ! misho 8477: ** CAPI3REF: Recover snapshots from a wal file
! 8478: ** EXPERIMENTAL
! 8479: **
! 8480: ** If all connections disconnect from a database file but do not perform
! 8481: ** a checkpoint, the existing wal file is opened along with the database
! 8482: ** file the next time the database is opened. At this point it is only
! 8483: ** possible to successfully call sqlite3_snapshot_open() to open the most
! 8484: ** recent snapshot of the database (the one at the head of the wal file),
! 8485: ** even though the wal file may contain other valid snapshots for which
! 8486: ** clients have sqlite3_snapshot handles.
! 8487: **
! 8488: ** This function attempts to scan the wal file associated with database zDb
! 8489: ** of database handle db and make all valid snapshots available to
! 8490: ** sqlite3_snapshot_open(). It is an error if there is already a read
! 8491: ** transaction open on the database, or if the database is not a wal mode
! 8492: ** database.
! 8493: **
! 8494: ** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
! 8495: */
! 8496: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
! 8497:
! 8498: /*
1.2 misho 8499: ** Undo the hack that converts floating point types to integer for
8500: ** builds on processors without floating point support.
8501: */
8502: #ifdef SQLITE_OMIT_FLOATING_POINT
8503: # undef double
8504: #endif
8505:
8506: #ifdef __cplusplus
8507: } /* End of the 'extern "C"' block */
8508: #endif
1.4 misho 8509: #endif /* SQLITE3_H */
1.2 misho 8510:
1.4 misho 8511: /******** Begin file sqlite3rtree.h *********/
1.2 misho 8512: /*
8513: ** 2010 August 30
8514: **
8515: ** The author disclaims copyright to this source code. In place of
8516: ** a legal notice, here is a blessing:
8517: **
8518: ** May you do good and not evil.
8519: ** May you find forgiveness for yourself and forgive others.
8520: ** May you share freely, never taking more than you give.
8521: **
8522: *************************************************************************
8523: */
8524:
8525: #ifndef _SQLITE3RTREE_H_
8526: #define _SQLITE3RTREE_H_
8527:
8528:
8529: #ifdef __cplusplus
8530: extern "C" {
8531: #endif
8532:
8533: typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
1.4 misho 8534: typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
8535:
8536: /* The double-precision datatype used by RTree depends on the
8537: ** SQLITE_RTREE_INT_ONLY compile-time option.
8538: */
8539: #ifdef SQLITE_RTREE_INT_ONLY
8540: typedef sqlite3_int64 sqlite3_rtree_dbl;
8541: #else
8542: typedef double sqlite3_rtree_dbl;
8543: #endif
1.2 misho 8544:
8545: /*
8546: ** Register a geometry callback named zGeom that can be used as part of an
8547: ** R-Tree geometry query as follows:
8548: **
8549: ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
8550: */
8551: SQLITE_API int sqlite3_rtree_geometry_callback(
8552: sqlite3 *db,
8553: const char *zGeom,
1.4 misho 8554: int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
1.2 misho 8555: void *pContext
8556: );
8557:
8558:
8559: /*
8560: ** A pointer to a structure of the following type is passed as the first
8561: ** argument to callbacks registered using rtree_geometry_callback().
8562: */
8563: struct sqlite3_rtree_geometry {
8564: void *pContext; /* Copy of pContext passed to s_r_g_c() */
8565: int nParam; /* Size of array aParam[] */
1.4 misho 8566: sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */
1.2 misho 8567: void *pUser; /* Callback implementation user data */
8568: void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
8569: };
8570:
1.4 misho 8571: /*
8572: ** Register a 2nd-generation geometry callback named zScore that can be
8573: ** used as part of an R-Tree geometry query as follows:
8574: **
8575: ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
8576: */
8577: SQLITE_API int sqlite3_rtree_query_callback(
8578: sqlite3 *db,
8579: const char *zQueryFunc,
8580: int (*xQueryFunc)(sqlite3_rtree_query_info*),
8581: void *pContext,
8582: void (*xDestructor)(void*)
8583: );
8584:
8585:
8586: /*
8587: ** A pointer to a structure of the following type is passed as the
8588: ** argument to scored geometry callback registered using
8589: ** sqlite3_rtree_query_callback().
8590: **
8591: ** Note that the first 5 fields of this structure are identical to
8592: ** sqlite3_rtree_geometry. This structure is a subclass of
8593: ** sqlite3_rtree_geometry.
8594: */
8595: struct sqlite3_rtree_query_info {
8596: void *pContext; /* pContext from when function registered */
8597: int nParam; /* Number of function parameters */
8598: sqlite3_rtree_dbl *aParam; /* value of function parameters */
8599: void *pUser; /* callback can use this, if desired */
8600: void (*xDelUser)(void*); /* function to free pUser */
8601: sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */
8602: unsigned int *anQueue; /* Number of pending entries in the queue */
8603: int nCoord; /* Number of coordinates */
8604: int iLevel; /* Level of current node or entry */
8605: int mxLevel; /* The largest iLevel value in the tree */
8606: sqlite3_int64 iRowid; /* Rowid for current entry */
8607: sqlite3_rtree_dbl rParentScore; /* Score of parent node */
8608: int eParentWithin; /* Visibility of parent node */
8609: int eWithin; /* OUT: Visiblity */
8610: sqlite3_rtree_dbl rScore; /* OUT: Write the score here */
8611: /* The following fields are only available in 3.8.11 and later */
8612: sqlite3_value **apSqlParam; /* Original SQL values of parameters */
8613: };
8614:
8615: /*
8616: ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
8617: */
8618: #define NOT_WITHIN 0 /* Object completely outside of query region */
8619: #define PARTLY_WITHIN 1 /* Object partially overlaps query region */
8620: #define FULLY_WITHIN 2 /* Object fully contained within query region */
8621:
1.2 misho 8622:
8623: #ifdef __cplusplus
8624: } /* end of the 'extern "C"' block */
8625: #endif
8626:
8627: #endif /* ifndef _SQLITE3RTREE_H_ */
8628:
1.4 misho 8629: /******** End of sqlite3rtree.h *********/
8630: /******** Begin file sqlite3session.h *********/
8631:
8632: #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
8633: #define __SQLITESESSION_H_ 1
8634:
8635: /*
8636: ** Make sure we can call this stuff from C++.
8637: */
8638: #ifdef __cplusplus
8639: extern "C" {
8640: #endif
8641:
8642:
8643: /*
8644: ** CAPI3REF: Session Object Handle
8645: */
8646: typedef struct sqlite3_session sqlite3_session;
8647:
8648: /*
8649: ** CAPI3REF: Changeset Iterator Handle
8650: */
8651: typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
8652:
8653: /*
8654: ** CAPI3REF: Create A New Session Object
8655: **
8656: ** Create a new session object attached to database handle db. If successful,
8657: ** a pointer to the new object is written to *ppSession and SQLITE_OK is
8658: ** returned. If an error occurs, *ppSession is set to NULL and an SQLite
8659: ** error code (e.g. SQLITE_NOMEM) is returned.
8660: **
8661: ** It is possible to create multiple session objects attached to a single
8662: ** database handle.
8663: **
8664: ** Session objects created using this function should be deleted using the
8665: ** [sqlite3session_delete()] function before the database handle that they
8666: ** are attached to is itself closed. If the database handle is closed before
8667: ** the session object is deleted, then the results of calling any session
8668: ** module function, including [sqlite3session_delete()] on the session object
8669: ** are undefined.
8670: **
8671: ** Because the session module uses the [sqlite3_preupdate_hook()] API, it
8672: ** is not possible for an application to register a pre-update hook on a
8673: ** database handle that has one or more session objects attached. Nor is
8674: ** it possible to create a session object attached to a database handle for
8675: ** which a pre-update hook is already defined. The results of attempting
8676: ** either of these things are undefined.
8677: **
8678: ** The session object will be used to create changesets for tables in
8679: ** database zDb, where zDb is either "main", or "temp", or the name of an
8680: ** attached database. It is not an error if database zDb is not attached
8681: ** to the database when the session object is created.
8682: */
1.4.2.1 ! misho 8683: SQLITE_API int sqlite3session_create(
1.4 misho 8684: sqlite3 *db, /* Database handle */
8685: const char *zDb, /* Name of db (e.g. "main") */
8686: sqlite3_session **ppSession /* OUT: New session object */
8687: );
8688:
8689: /*
8690: ** CAPI3REF: Delete A Session Object
8691: **
8692: ** Delete a session object previously allocated using
8693: ** [sqlite3session_create()]. Once a session object has been deleted, the
8694: ** results of attempting to use pSession with any other session module
8695: ** function are undefined.
8696: **
8697: ** Session objects must be deleted before the database handle to which they
8698: ** are attached is closed. Refer to the documentation for
8699: ** [sqlite3session_create()] for details.
8700: */
1.4.2.1 ! misho 8701: SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
1.4 misho 8702:
8703:
8704: /*
8705: ** CAPI3REF: Enable Or Disable A Session Object
8706: **
8707: ** Enable or disable the recording of changes by a session object. When
8708: ** enabled, a session object records changes made to the database. When
8709: ** disabled - it does not. A newly created session object is enabled.
8710: ** Refer to the documentation for [sqlite3session_changeset()] for further
8711: ** details regarding how enabling and disabling a session object affects
8712: ** the eventual changesets.
8713: **
8714: ** Passing zero to this function disables the session. Passing a value
8715: ** greater than zero enables it. Passing a value less than zero is a
8716: ** no-op, and may be used to query the current state of the session.
8717: **
8718: ** The return value indicates the final state of the session object: 0 if
8719: ** the session is disabled, or 1 if it is enabled.
8720: */
1.4.2.1 ! misho 8721: SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
1.4 misho 8722:
8723: /*
8724: ** CAPI3REF: Set Or Clear the Indirect Change Flag
8725: **
8726: ** Each change recorded by a session object is marked as either direct or
8727: ** indirect. A change is marked as indirect if either:
8728: **
8729: ** <ul>
8730: ** <li> The session object "indirect" flag is set when the change is
8731: ** made, or
8732: ** <li> The change is made by an SQL trigger or foreign key action
8733: ** instead of directly as a result of a users SQL statement.
8734: ** </ul>
8735: **
8736: ** If a single row is affected by more than one operation within a session,
8737: ** then the change is considered indirect if all operations meet the criteria
8738: ** for an indirect change above, or direct otherwise.
8739: **
8740: ** This function is used to set, clear or query the session object indirect
8741: ** flag. If the second argument passed to this function is zero, then the
8742: ** indirect flag is cleared. If it is greater than zero, the indirect flag
8743: ** is set. Passing a value less than zero does not modify the current value
8744: ** of the indirect flag, and may be used to query the current state of the
8745: ** indirect flag for the specified session object.
8746: **
8747: ** The return value indicates the final state of the indirect flag: 0 if
8748: ** it is clear, or 1 if it is set.
8749: */
1.4.2.1 ! misho 8750: SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
1.4 misho 8751:
8752: /*
8753: ** CAPI3REF: Attach A Table To A Session Object
8754: **
8755: ** If argument zTab is not NULL, then it is the name of a table to attach
8756: ** to the session object passed as the first argument. All subsequent changes
8757: ** made to the table while the session object is enabled will be recorded. See
8758: ** documentation for [sqlite3session_changeset()] for further details.
8759: **
8760: ** Or, if argument zTab is NULL, then changes are recorded for all tables
8761: ** in the database. If additional tables are added to the database (by
8762: ** executing "CREATE TABLE" statements) after this call is made, changes for
8763: ** the new tables are also recorded.
8764: **
8765: ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
8766: ** defined as part of their CREATE TABLE statement. It does not matter if the
8767: ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
8768: ** KEY may consist of a single column, or may be a composite key.
8769: **
8770: ** It is not an error if the named table does not exist in the database. Nor
8771: ** is it an error if the named table does not have a PRIMARY KEY. However,
8772: ** no changes will be recorded in either of these scenarios.
8773: **
8774: ** Changes are not recorded for individual rows that have NULL values stored
8775: ** in one or more of their PRIMARY KEY columns.
8776: **
8777: ** SQLITE_OK is returned if the call completes without error. Or, if an error
8778: ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
8779: */
1.4.2.1 ! misho 8780: SQLITE_API int sqlite3session_attach(
1.4 misho 8781: sqlite3_session *pSession, /* Session object */
8782: const char *zTab /* Table name */
8783: );
8784:
8785: /*
8786: ** CAPI3REF: Set a table filter on a Session Object.
8787: **
8788: ** The second argument (xFilter) is the "filter callback". For changes to rows
1.4.2.1 ! misho 8789: ** in tables that are not attached to the Session object, the filter is called
1.4 misho 8790: ** to determine whether changes to the table's rows should be tracked or not.
8791: ** If xFilter returns 0, changes is not tracked. Note that once a table is
8792: ** attached, xFilter will not be called again.
8793: */
1.4.2.1 ! misho 8794: SQLITE_API void sqlite3session_table_filter(
1.4 misho 8795: sqlite3_session *pSession, /* Session object */
8796: int(*xFilter)(
8797: void *pCtx, /* Copy of third arg to _filter_table() */
8798: const char *zTab /* Table name */
8799: ),
8800: void *pCtx /* First argument passed to xFilter */
8801: );
8802:
8803: /*
8804: ** CAPI3REF: Generate A Changeset From A Session Object
8805: **
8806: ** Obtain a changeset containing changes to the tables attached to the
8807: ** session object passed as the first argument. If successful,
8808: ** set *ppChangeset to point to a buffer containing the changeset
8809: ** and *pnChangeset to the size of the changeset in bytes before returning
8810: ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
8811: ** zero and return an SQLite error code.
8812: **
8813: ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
8814: ** each representing a change to a single row of an attached table. An INSERT
8815: ** change contains the values of each field of a new database row. A DELETE
8816: ** contains the original values of each field of a deleted database row. An
8817: ** UPDATE change contains the original values of each field of an updated
8818: ** database row along with the updated values for each updated non-primary-key
8819: ** column. It is not possible for an UPDATE change to represent a change that
8820: ** modifies the values of primary key columns. If such a change is made, it
8821: ** is represented in a changeset as a DELETE followed by an INSERT.
8822: **
8823: ** Changes are not recorded for rows that have NULL values stored in one or
8824: ** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
8825: ** no corresponding change is present in the changesets returned by this
8826: ** function. If an existing row with one or more NULL values stored in
8827: ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
8828: ** only an INSERT is appears in the changeset. Similarly, if an existing row
8829: ** with non-NULL PRIMARY KEY values is updated so that one or more of its
8830: ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
8831: ** DELETE change only.
8832: **
8833: ** The contents of a changeset may be traversed using an iterator created
8834: ** using the [sqlite3changeset_start()] API. A changeset may be applied to
8835: ** a database with a compatible schema using the [sqlite3changeset_apply()]
8836: ** API.
8837: **
8838: ** Within a changeset generated by this function, all changes related to a
8839: ** single table are grouped together. In other words, when iterating through
8840: ** a changeset or when applying a changeset to a database, all changes related
8841: ** to a single table are processed before moving on to the next table. Tables
8842: ** are sorted in the same order in which they were attached (or auto-attached)
8843: ** to the sqlite3_session object. The order in which the changes related to
8844: ** a single table are stored is undefined.
8845: **
8846: ** Following a successful call to this function, it is the responsibility of
8847: ** the caller to eventually free the buffer that *ppChangeset points to using
8848: ** [sqlite3_free()].
8849: **
8850: ** <h3>Changeset Generation</h3>
8851: **
8852: ** Once a table has been attached to a session object, the session object
8853: ** records the primary key values of all new rows inserted into the table.
8854: ** It also records the original primary key and other column values of any
8855: ** deleted or updated rows. For each unique primary key value, data is only
8856: ** recorded once - the first time a row with said primary key is inserted,
8857: ** updated or deleted in the lifetime of the session.
8858: **
8859: ** There is one exception to the previous paragraph: when a row is inserted,
8860: ** updated or deleted, if one or more of its primary key columns contain a
8861: ** NULL value, no record of the change is made.
8862: **
8863: ** The session object therefore accumulates two types of records - those
8864: ** that consist of primary key values only (created when the user inserts
8865: ** a new record) and those that consist of the primary key values and the
8866: ** original values of other table columns (created when the users deletes
8867: ** or updates a record).
8868: **
8869: ** When this function is called, the requested changeset is created using
8870: ** both the accumulated records and the current contents of the database
8871: ** file. Specifically:
8872: **
8873: ** <ul>
8874: ** <li> For each record generated by an insert, the database is queried
8875: ** for a row with a matching primary key. If one is found, an INSERT
8876: ** change is added to the changeset. If no such row is found, no change
8877: ** is added to the changeset.
8878: **
8879: ** <li> For each record generated by an update or delete, the database is
8880: ** queried for a row with a matching primary key. If such a row is
8881: ** found and one or more of the non-primary key fields have been
8882: ** modified from their original values, an UPDATE change is added to
8883: ** the changeset. Or, if no such row is found in the table, a DELETE
8884: ** change is added to the changeset. If there is a row with a matching
8885: ** primary key in the database, but all fields contain their original
8886: ** values, no change is added to the changeset.
8887: ** </ul>
8888: **
8889: ** This means, amongst other things, that if a row is inserted and then later
8890: ** deleted while a session object is active, neither the insert nor the delete
8891: ** will be present in the changeset. Or if a row is deleted and then later a
8892: ** row with the same primary key values inserted while a session object is
8893: ** active, the resulting changeset will contain an UPDATE change instead of
8894: ** a DELETE and an INSERT.
8895: **
8896: ** When a session object is disabled (see the [sqlite3session_enable()] API),
8897: ** it does not accumulate records when rows are inserted, updated or deleted.
8898: ** This may appear to have some counter-intuitive effects if a single row
8899: ** is written to more than once during a session. For example, if a row
8900: ** is inserted while a session object is enabled, then later deleted while
8901: ** the same session object is disabled, no INSERT record will appear in the
8902: ** changeset, even though the delete took place while the session was disabled.
8903: ** Or, if one field of a row is updated while a session is disabled, and
8904: ** another field of the same row is updated while the session is enabled, the
8905: ** resulting changeset will contain an UPDATE change that updates both fields.
8906: */
1.4.2.1 ! misho 8907: SQLITE_API int sqlite3session_changeset(
1.4 misho 8908: sqlite3_session *pSession, /* Session object */
8909: int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */
8910: void **ppChangeset /* OUT: Buffer containing changeset */
8911: );
8912:
8913: /*
8914: ** CAPI3REF: Load The Difference Between Tables Into A Session
8915: **
8916: ** If it is not already attached to the session object passed as the first
8917: ** argument, this function attaches table zTbl in the same manner as the
8918: ** [sqlite3session_attach()] function. If zTbl does not exist, or if it
8919: ** does not have a primary key, this function is a no-op (but does not return
8920: ** an error).
8921: **
8922: ** Argument zFromDb must be the name of a database ("main", "temp" etc.)
8923: ** attached to the same database handle as the session object that contains
8924: ** a table compatible with the table attached to the session by this function.
8925: ** A table is considered compatible if it:
8926: **
8927: ** <ul>
8928: ** <li> Has the same name,
8929: ** <li> Has the same set of columns declared in the same order, and
8930: ** <li> Has the same PRIMARY KEY definition.
8931: ** </ul>
8932: **
8933: ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
8934: ** are compatible but do not have any PRIMARY KEY columns, it is not an error
8935: ** but no changes are added to the session object. As with other session
8936: ** APIs, tables without PRIMARY KEYs are simply ignored.
8937: **
8938: ** This function adds a set of changes to the session object that could be
8939: ** used to update the table in database zFrom (call this the "from-table")
8940: ** so that its content is the same as the table attached to the session
8941: ** object (call this the "to-table"). Specifically:
8942: **
8943: ** <ul>
8944: ** <li> For each row (primary key) that exists in the to-table but not in
8945: ** the from-table, an INSERT record is added to the session object.
8946: **
8947: ** <li> For each row (primary key) that exists in the to-table but not in
8948: ** the from-table, a DELETE record is added to the session object.
8949: **
8950: ** <li> For each row (primary key) that exists in both tables, but features
1.4.2.1 ! misho 8951: ** different non-PK values in each, an UPDATE record is added to the
! 8952: ** session.
1.4 misho 8953: ** </ul>
8954: **
8955: ** To clarify, if this function is called and then a changeset constructed
8956: ** using [sqlite3session_changeset()], then after applying that changeset to
8957: ** database zFrom the contents of the two compatible tables would be
8958: ** identical.
8959: **
8960: ** It an error if database zFrom does not exist or does not contain the
8961: ** required compatible table.
8962: **
8963: ** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite
8964: ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
8965: ** may be set to point to a buffer containing an English language error
8966: ** message. It is the responsibility of the caller to free this buffer using
8967: ** sqlite3_free().
8968: */
1.4.2.1 ! misho 8969: SQLITE_API int sqlite3session_diff(
1.4 misho 8970: sqlite3_session *pSession,
8971: const char *zFromDb,
8972: const char *zTbl,
8973: char **pzErrMsg
8974: );
8975:
8976:
8977: /*
8978: ** CAPI3REF: Generate A Patchset From A Session Object
8979: **
8980: ** The differences between a patchset and a changeset are that:
8981: **
8982: ** <ul>
8983: ** <li> DELETE records consist of the primary key fields only. The
8984: ** original values of other fields are omitted.
8985: ** <li> The original values of any modified fields are omitted from
8986: ** UPDATE records.
8987: ** </ul>
8988: **
8989: ** A patchset blob may be used with up to date versions of all
8990: ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
8991: ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
8992: ** attempting to use a patchset blob with old versions of the
8993: ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
8994: **
8995: ** Because the non-primary key "old.*" fields are omitted, no
8996: ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
8997: ** is passed to the sqlite3changeset_apply() API. Other conflict types work
8998: ** in the same way as for changesets.
8999: **
9000: ** Changes within a patchset are ordered in the same way as for changesets
9001: ** generated by the sqlite3session_changeset() function (i.e. all changes for
9002: ** a single table are grouped together, tables appear in the order in which
9003: ** they were attached to the session object).
9004: */
1.4.2.1 ! misho 9005: SQLITE_API int sqlite3session_patchset(
1.4 misho 9006: sqlite3_session *pSession, /* Session object */
9007: int *pnPatchset, /* OUT: Size of buffer at *ppChangeset */
9008: void **ppPatchset /* OUT: Buffer containing changeset */
9009: );
9010:
9011: /*
9012: ** CAPI3REF: Test if a changeset has recorded any changes.
9013: **
9014: ** Return non-zero if no changes to attached tables have been recorded by
9015: ** the session object passed as the first argument. Otherwise, if one or
9016: ** more changes have been recorded, return zero.
9017: **
9018: ** Even if this function returns zero, it is possible that calling
9019: ** [sqlite3session_changeset()] on the session handle may still return a
9020: ** changeset that contains no changes. This can happen when a row in
9021: ** an attached table is modified and then later on the original values
9022: ** are restored. However, if this function returns non-zero, then it is
9023: ** guaranteed that a call to sqlite3session_changeset() will return a
9024: ** changeset containing zero changes.
9025: */
1.4.2.1 ! misho 9026: SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
1.4 misho 9027:
9028: /*
9029: ** CAPI3REF: Create An Iterator To Traverse A Changeset
9030: **
9031: ** Create an iterator used to iterate through the contents of a changeset.
9032: ** If successful, *pp is set to point to the iterator handle and SQLITE_OK
9033: ** is returned. Otherwise, if an error occurs, *pp is set to zero and an
9034: ** SQLite error code is returned.
9035: **
9036: ** The following functions can be used to advance and query a changeset
9037: ** iterator created by this function:
9038: **
9039: ** <ul>
9040: ** <li> [sqlite3changeset_next()]
9041: ** <li> [sqlite3changeset_op()]
9042: ** <li> [sqlite3changeset_new()]
9043: ** <li> [sqlite3changeset_old()]
9044: ** </ul>
9045: **
9046: ** It is the responsibility of the caller to eventually destroy the iterator
9047: ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
9048: ** changeset (pChangeset) must remain valid until after the iterator is
9049: ** destroyed.
9050: **
9051: ** Assuming the changeset blob was created by one of the
9052: ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
9053: ** [sqlite3changeset_invert()] functions, all changes within the changeset
9054: ** that apply to a single table are grouped together. This means that when
9055: ** an application iterates through a changeset using an iterator created by
1.4.2.1 ! misho 9056: ** this function, all changes that relate to a single table are visited
1.4 misho 9057: ** consecutively. There is no chance that the iterator will visit a change
9058: ** the applies to table X, then one for table Y, and then later on visit
9059: ** another change for table X.
9060: */
1.4.2.1 ! misho 9061: SQLITE_API int sqlite3changeset_start(
1.4 misho 9062: sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */
9063: int nChangeset, /* Size of changeset blob in bytes */
9064: void *pChangeset /* Pointer to blob containing changeset */
9065: );
9066:
9067:
9068: /*
9069: ** CAPI3REF: Advance A Changeset Iterator
9070: **
9071: ** This function may only be used with iterators created by function
9072: ** [sqlite3changeset_start()]. If it is called on an iterator passed to
9073: ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
9074: ** is returned and the call has no effect.
9075: **
9076: ** Immediately after an iterator is created by sqlite3changeset_start(), it
9077: ** does not point to any change in the changeset. Assuming the changeset
9078: ** is not empty, the first call to this function advances the iterator to
9079: ** point to the first change in the changeset. Each subsequent call advances
9080: ** the iterator to point to the next change in the changeset (if any). If
9081: ** no error occurs and the iterator points to a valid change after a call
9082: ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
9083: ** Otherwise, if all changes in the changeset have already been visited,
9084: ** SQLITE_DONE is returned.
9085: **
9086: ** If an error occurs, an SQLite error code is returned. Possible error
9087: ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
9088: ** SQLITE_NOMEM.
9089: */
1.4.2.1 ! misho 9090: SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
1.4 misho 9091:
9092: /*
9093: ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
9094: **
9095: ** The pIter argument passed to this function may either be an iterator
9096: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
9097: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
9098: ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
9099: ** is not the case, this function returns [SQLITE_MISUSE].
9100: **
9101: ** If argument pzTab is not NULL, then *pzTab is set to point to a
9102: ** nul-terminated utf-8 encoded string containing the name of the table
9103: ** affected by the current change. The buffer remains valid until either
9104: ** sqlite3changeset_next() is called on the iterator or until the
9105: ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is
9106: ** set to the number of columns in the table affected by the change. If
9107: ** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change
9108: ** is an indirect change, or false (0) otherwise. See the documentation for
9109: ** [sqlite3session_indirect()] for a description of direct and indirect
9110: ** changes. Finally, if pOp is not NULL, then *pOp is set to one of
9111: ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the
9112: ** type of change that the iterator currently points to.
9113: **
9114: ** If no error occurs, SQLITE_OK is returned. If an error does occur, an
9115: ** SQLite error code is returned. The values of the output variables may not
9116: ** be trusted in this case.
9117: */
1.4.2.1 ! misho 9118: SQLITE_API int sqlite3changeset_op(
1.4 misho 9119: sqlite3_changeset_iter *pIter, /* Iterator object */
9120: const char **pzTab, /* OUT: Pointer to table name */
9121: int *pnCol, /* OUT: Number of columns in table */
9122: int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */
9123: int *pbIndirect /* OUT: True for an 'indirect' change */
9124: );
9125:
9126: /*
9127: ** CAPI3REF: Obtain The Primary Key Definition Of A Table
9128: **
9129: ** For each modified table, a changeset includes the following:
9130: **
9131: ** <ul>
9132: ** <li> The number of columns in the table, and
9133: ** <li> Which of those columns make up the tables PRIMARY KEY.
9134: ** </ul>
9135: **
9136: ** This function is used to find which columns comprise the PRIMARY KEY of
9137: ** the table modified by the change that iterator pIter currently points to.
9138: ** If successful, *pabPK is set to point to an array of nCol entries, where
9139: ** nCol is the number of columns in the table. Elements of *pabPK are set to
9140: ** 0x01 if the corresponding column is part of the tables primary key, or
9141: ** 0x00 if it is not.
9142: **
1.4.2.1 ! misho 9143: ** If argument pnCol is not NULL, then *pnCol is set to the number of columns
1.4 misho 9144: ** in the table.
9145: **
9146: ** If this function is called when the iterator does not point to a valid
9147: ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
9148: ** SQLITE_OK is returned and the output variables populated as described
9149: ** above.
9150: */
1.4.2.1 ! misho 9151: SQLITE_API int sqlite3changeset_pk(
1.4 misho 9152: sqlite3_changeset_iter *pIter, /* Iterator object */
9153: unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */
9154: int *pnCol /* OUT: Number of entries in output array */
9155: );
9156:
9157: /*
9158: ** CAPI3REF: Obtain old.* Values From A Changeset Iterator
9159: **
9160: ** The pIter argument passed to this function may either be an iterator
9161: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
9162: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
9163: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
9164: ** Furthermore, it may only be called if the type of change that the iterator
9165: ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
9166: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
9167: **
9168: ** Argument iVal must be greater than or equal to 0, and less than the number
9169: ** of columns in the table affected by the current change. Otherwise,
9170: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
9171: **
9172: ** If successful, this function sets *ppValue to point to a protected
9173: ** sqlite3_value object containing the iVal'th value from the vector of
9174: ** original row values stored as part of the UPDATE or DELETE change and
9175: ** returns SQLITE_OK. The name of the function comes from the fact that this
9176: ** is similar to the "old.*" columns available to update or delete triggers.
9177: **
9178: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
9179: ** is returned and *ppValue is set to NULL.
9180: */
1.4.2.1 ! misho 9181: SQLITE_API int sqlite3changeset_old(
1.4 misho 9182: sqlite3_changeset_iter *pIter, /* Changeset iterator */
9183: int iVal, /* Column number */
9184: sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */
9185: );
9186:
9187: /*
9188: ** CAPI3REF: Obtain new.* Values From A Changeset Iterator
9189: **
9190: ** The pIter argument passed to this function may either be an iterator
9191: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
9192: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
9193: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
9194: ** Furthermore, it may only be called if the type of change that the iterator
9195: ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
9196: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
9197: **
9198: ** Argument iVal must be greater than or equal to 0, and less than the number
9199: ** of columns in the table affected by the current change. Otherwise,
9200: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
9201: **
9202: ** If successful, this function sets *ppValue to point to a protected
9203: ** sqlite3_value object containing the iVal'th value from the vector of
9204: ** new row values stored as part of the UPDATE or INSERT change and
9205: ** returns SQLITE_OK. If the change is an UPDATE and does not include
9206: ** a new value for the requested column, *ppValue is set to NULL and
9207: ** SQLITE_OK returned. The name of the function comes from the fact that
9208: ** this is similar to the "new.*" columns available to update or delete
9209: ** triggers.
9210: **
9211: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
9212: ** is returned and *ppValue is set to NULL.
9213: */
1.4.2.1 ! misho 9214: SQLITE_API int sqlite3changeset_new(
1.4 misho 9215: sqlite3_changeset_iter *pIter, /* Changeset iterator */
9216: int iVal, /* Column number */
9217: sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */
9218: );
9219:
9220: /*
9221: ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
9222: **
9223: ** This function should only be used with iterator objects passed to a
9224: ** conflict-handler callback by [sqlite3changeset_apply()] with either
9225: ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
9226: ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
9227: ** is set to NULL.
9228: **
9229: ** Argument iVal must be greater than or equal to 0, and less than the number
9230: ** of columns in the table affected by the current change. Otherwise,
9231: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
9232: **
9233: ** If successful, this function sets *ppValue to point to a protected
9234: ** sqlite3_value object containing the iVal'th value from the
9235: ** "conflicting row" associated with the current conflict-handler callback
9236: ** and returns SQLITE_OK.
9237: **
9238: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
9239: ** is returned and *ppValue is set to NULL.
9240: */
1.4.2.1 ! misho 9241: SQLITE_API int sqlite3changeset_conflict(
1.4 misho 9242: sqlite3_changeset_iter *pIter, /* Changeset iterator */
9243: int iVal, /* Column number */
9244: sqlite3_value **ppValue /* OUT: Value from conflicting row */
9245: );
9246:
9247: /*
9248: ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
9249: **
9250: ** This function may only be called with an iterator passed to an
9251: ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
9252: ** it sets the output variable to the total number of known foreign key
9253: ** violations in the destination database and returns SQLITE_OK.
9254: **
9255: ** In all other cases this function returns SQLITE_MISUSE.
9256: */
1.4.2.1 ! misho 9257: SQLITE_API int sqlite3changeset_fk_conflicts(
1.4 misho 9258: sqlite3_changeset_iter *pIter, /* Changeset iterator */
9259: int *pnOut /* OUT: Number of FK violations */
9260: );
9261:
9262:
9263: /*
9264: ** CAPI3REF: Finalize A Changeset Iterator
9265: **
9266: ** This function is used to finalize an iterator allocated with
9267: ** [sqlite3changeset_start()].
9268: **
9269: ** This function should only be called on iterators created using the
9270: ** [sqlite3changeset_start()] function. If an application calls this
9271: ** function with an iterator passed to a conflict-handler by
9272: ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
9273: ** call has no effect.
9274: **
9275: ** If an error was encountered within a call to an sqlite3changeset_xxx()
9276: ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
9277: ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
9278: ** to that error is returned by this function. Otherwise, SQLITE_OK is
9279: ** returned. This is to allow the following pattern (pseudo-code):
9280: **
9281: ** sqlite3changeset_start();
9282: ** while( SQLITE_ROW==sqlite3changeset_next() ){
9283: ** // Do something with change.
9284: ** }
9285: ** rc = sqlite3changeset_finalize();
9286: ** if( rc!=SQLITE_OK ){
9287: ** // An error has occurred
9288: ** }
9289: */
1.4.2.1 ! misho 9290: SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
1.4 misho 9291:
9292: /*
9293: ** CAPI3REF: Invert A Changeset
9294: **
9295: ** This function is used to "invert" a changeset object. Applying an inverted
9296: ** changeset to a database reverses the effects of applying the uninverted
9297: ** changeset. Specifically:
9298: **
9299: ** <ul>
9300: ** <li> Each DELETE change is changed to an INSERT, and
9301: ** <li> Each INSERT change is changed to a DELETE, and
9302: ** <li> For each UPDATE change, the old.* and new.* values are exchanged.
9303: ** </ul>
9304: **
9305: ** This function does not change the order in which changes appear within
9306: ** the changeset. It merely reverses the sense of each individual change.
9307: **
9308: ** If successful, a pointer to a buffer containing the inverted changeset
9309: ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
9310: ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
9311: ** zeroed and an SQLite error code returned.
9312: **
9313: ** It is the responsibility of the caller to eventually call sqlite3_free()
9314: ** on the *ppOut pointer to free the buffer allocation following a successful
9315: ** call to this function.
9316: **
9317: ** WARNING/TODO: This function currently assumes that the input is a valid
9318: ** changeset. If it is not, the results are undefined.
9319: */
1.4.2.1 ! misho 9320: SQLITE_API int sqlite3changeset_invert(
1.4 misho 9321: int nIn, const void *pIn, /* Input changeset */
9322: int *pnOut, void **ppOut /* OUT: Inverse of input */
9323: );
9324:
9325: /*
9326: ** CAPI3REF: Concatenate Two Changeset Objects
9327: **
9328: ** This function is used to concatenate two changesets, A and B, into a
9329: ** single changeset. The result is a changeset equivalent to applying
9330: ** changeset A followed by changeset B.
9331: **
9332: ** This function combines the two input changesets using an
9333: ** sqlite3_changegroup object. Calling it produces similar results as the
9334: ** following code fragment:
9335: **
9336: ** sqlite3_changegroup *pGrp;
9337: ** rc = sqlite3_changegroup_new(&pGrp);
9338: ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
9339: ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
9340: ** if( rc==SQLITE_OK ){
9341: ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
9342: ** }else{
9343: ** *ppOut = 0;
9344: ** *pnOut = 0;
9345: ** }
9346: **
9347: ** Refer to the sqlite3_changegroup documentation below for details.
9348: */
1.4.2.1 ! misho 9349: SQLITE_API int sqlite3changeset_concat(
1.4 misho 9350: int nA, /* Number of bytes in buffer pA */
9351: void *pA, /* Pointer to buffer containing changeset A */
9352: int nB, /* Number of bytes in buffer pB */
9353: void *pB, /* Pointer to buffer containing changeset B */
9354: int *pnOut, /* OUT: Number of bytes in output changeset */
9355: void **ppOut /* OUT: Buffer containing output changeset */
9356: );
9357:
9358:
9359: /*
1.4.2.1 ! misho 9360: ** CAPI3REF: Changegroup Handle
1.4 misho 9361: */
9362: typedef struct sqlite3_changegroup sqlite3_changegroup;
9363:
9364: /*
1.4.2.1 ! misho 9365: ** CAPI3REF: Create A New Changegroup Object
1.4 misho 9366: **
9367: ** An sqlite3_changegroup object is used to combine two or more changesets
9368: ** (or patchsets) into a single changeset (or patchset). A single changegroup
9369: ** object may combine changesets or patchsets, but not both. The output is
9370: ** always in the same format as the input.
9371: **
9372: ** If successful, this function returns SQLITE_OK and populates (*pp) with
9373: ** a pointer to a new sqlite3_changegroup object before returning. The caller
9374: ** should eventually free the returned object using a call to
9375: ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
9376: ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
9377: **
9378: ** The usual usage pattern for an sqlite3_changegroup object is as follows:
9379: **
9380: ** <ul>
9381: ** <li> It is created using a call to sqlite3changegroup_new().
9382: **
9383: ** <li> Zero or more changesets (or patchsets) are added to the object
9384: ** by calling sqlite3changegroup_add().
9385: **
9386: ** <li> The result of combining all input changesets together is obtained
9387: ** by the application via a call to sqlite3changegroup_output().
9388: **
9389: ** <li> The object is deleted using a call to sqlite3changegroup_delete().
9390: ** </ul>
9391: **
9392: ** Any number of calls to add() and output() may be made between the calls to
9393: ** new() and delete(), and in any order.
9394: **
9395: ** As well as the regular sqlite3changegroup_add() and
9396: ** sqlite3changegroup_output() functions, also available are the streaming
9397: ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
9398: */
1.4.2.1 ! misho 9399: SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
1.4 misho 9400:
9401: /*
1.4.2.1 ! misho 9402: ** CAPI3REF: Add A Changeset To A Changegroup
! 9403: **
1.4 misho 9404: ** Add all changes within the changeset (or patchset) in buffer pData (size
9405: ** nData bytes) to the changegroup.
9406: **
9407: ** If the buffer contains a patchset, then all prior calls to this function
9408: ** on the same changegroup object must also have specified patchsets. Or, if
9409: ** the buffer contains a changeset, so must have the earlier calls to this
9410: ** function. Otherwise, SQLITE_ERROR is returned and no changes are added
9411: ** to the changegroup.
9412: **
9413: ** Rows within the changeset and changegroup are identified by the values in
9414: ** their PRIMARY KEY columns. A change in the changeset is considered to
9415: ** apply to the same row as a change already present in the changegroup if
9416: ** the two rows have the same primary key.
9417: **
1.4.2.1 ! misho 9418: ** Changes to rows that do not already appear in the changegroup are
1.4 misho 9419: ** simply copied into it. Or, if both the new changeset and the changegroup
9420: ** contain changes that apply to a single row, the final contents of the
9421: ** changegroup depends on the type of each change, as follows:
9422: **
9423: ** <table border=1 style="margin-left:8ex;margin-right:8ex">
9424: ** <tr><th style="white-space:pre">Existing Change </th>
9425: ** <th style="white-space:pre">New Change </th>
9426: ** <th>Output Change
9427: ** <tr><td>INSERT <td>INSERT <td>
9428: ** The new change is ignored. This case does not occur if the new
9429: ** changeset was recorded immediately after the changesets already
9430: ** added to the changegroup.
9431: ** <tr><td>INSERT <td>UPDATE <td>
9432: ** The INSERT change remains in the changegroup. The values in the
9433: ** INSERT change are modified as if the row was inserted by the
9434: ** existing change and then updated according to the new change.
9435: ** <tr><td>INSERT <td>DELETE <td>
9436: ** The existing INSERT is removed from the changegroup. The DELETE is
9437: ** not added.
9438: ** <tr><td>UPDATE <td>INSERT <td>
9439: ** The new change is ignored. This case does not occur if the new
9440: ** changeset was recorded immediately after the changesets already
9441: ** added to the changegroup.
9442: ** <tr><td>UPDATE <td>UPDATE <td>
9443: ** The existing UPDATE remains within the changegroup. It is amended
9444: ** so that the accompanying values are as if the row was updated once
9445: ** by the existing change and then again by the new change.
9446: ** <tr><td>UPDATE <td>DELETE <td>
9447: ** The existing UPDATE is replaced by the new DELETE within the
9448: ** changegroup.
9449: ** <tr><td>DELETE <td>INSERT <td>
9450: ** If one or more of the column values in the row inserted by the
9451: ** new change differ from those in the row deleted by the existing
9452: ** change, the existing DELETE is replaced by an UPDATE within the
9453: ** changegroup. Otherwise, if the inserted row is exactly the same
9454: ** as the deleted row, the existing DELETE is simply discarded.
9455: ** <tr><td>DELETE <td>UPDATE <td>
9456: ** The new change is ignored. This case does not occur if the new
9457: ** changeset was recorded immediately after the changesets already
9458: ** added to the changegroup.
9459: ** <tr><td>DELETE <td>DELETE <td>
9460: ** The new change is ignored. This case does not occur if the new
9461: ** changeset was recorded immediately after the changesets already
9462: ** added to the changegroup.
9463: ** </table>
9464: **
9465: ** If the new changeset contains changes to a table that is already present
9466: ** in the changegroup, then the number of columns and the position of the
9467: ** primary key columns for the table must be consistent. If this is not the
9468: ** case, this function fails with SQLITE_SCHEMA. If the input changeset
9469: ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
9470: ** returned. Or, if an out-of-memory condition occurs during processing, this
9471: ** function returns SQLITE_NOMEM. In all cases, if an error occurs the
9472: ** final contents of the changegroup is undefined.
9473: **
9474: ** If no error occurs, SQLITE_OK is returned.
9475: */
1.4.2.1 ! misho 9476: SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
1.4 misho 9477:
9478: /*
1.4.2.1 ! misho 9479: ** CAPI3REF: Obtain A Composite Changeset From A Changegroup
! 9480: **
1.4 misho 9481: ** Obtain a buffer containing a changeset (or patchset) representing the
9482: ** current contents of the changegroup. If the inputs to the changegroup
9483: ** were themselves changesets, the output is a changeset. Or, if the
9484: ** inputs were patchsets, the output is also a patchset.
9485: **
9486: ** As with the output of the sqlite3session_changeset() and
9487: ** sqlite3session_patchset() functions, all changes related to a single
9488: ** table are grouped together in the output of this function. Tables appear
9489: ** in the same order as for the very first changeset added to the changegroup.
9490: ** If the second or subsequent changesets added to the changegroup contain
9491: ** changes for tables that do not appear in the first changeset, they are
9492: ** appended onto the end of the output changeset, again in the order in
9493: ** which they are first encountered.
9494: **
9495: ** If an error occurs, an SQLite error code is returned and the output
9496: ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
9497: ** is returned and the output variables are set to the size of and a
9498: ** pointer to the output buffer, respectively. In this case it is the
9499: ** responsibility of the caller to eventually free the buffer using a
9500: ** call to sqlite3_free().
9501: */
1.4.2.1 ! misho 9502: SQLITE_API int sqlite3changegroup_output(
1.4 misho 9503: sqlite3_changegroup*,
9504: int *pnData, /* OUT: Size of output buffer in bytes */
9505: void **ppData /* OUT: Pointer to output buffer */
9506: );
9507:
9508: /*
1.4.2.1 ! misho 9509: ** CAPI3REF: Delete A Changegroup Object
1.4 misho 9510: */
1.4.2.1 ! misho 9511: SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
1.4 misho 9512:
9513: /*
9514: ** CAPI3REF: Apply A Changeset To A Database
9515: **
9516: ** Apply a changeset to a database. This function attempts to update the
9517: ** "main" database attached to handle db with the changes found in the
9518: ** changeset passed via the second and third arguments.
9519: **
9520: ** The fourth argument (xFilter) passed to this function is the "filter
9521: ** callback". If it is not NULL, then for each table affected by at least one
9522: ** change in the changeset, the filter callback is invoked with
9523: ** the table name as the second argument, and a copy of the context pointer
9524: ** passed as the sixth argument to this function as the first. If the "filter
9525: ** callback" returns zero, then no attempt is made to apply any changes to
9526: ** the table. Otherwise, if the return value is non-zero or the xFilter
9527: ** argument to this function is NULL, all changes related to the table are
9528: ** attempted.
9529: **
9530: ** For each table that is not excluded by the filter callback, this function
9531: ** tests that the target database contains a compatible table. A table is
9532: ** considered compatible if all of the following are true:
9533: **
9534: ** <ul>
9535: ** <li> The table has the same name as the name recorded in the
9536: ** changeset, and
1.4.2.1 ! misho 9537: ** <li> The table has at least as many columns as recorded in the
1.4 misho 9538: ** changeset, and
9539: ** <li> The table has primary key columns in the same position as
9540: ** recorded in the changeset.
9541: ** </ul>
9542: **
9543: ** If there is no compatible table, it is not an error, but none of the
9544: ** changes associated with the table are applied. A warning message is issued
9545: ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
9546: ** one such warning is issued for each table in the changeset.
9547: **
9548: ** For each change for which there is a compatible table, an attempt is made
9549: ** to modify the table contents according to the UPDATE, INSERT or DELETE
9550: ** change. If a change cannot be applied cleanly, the conflict handler
9551: ** function passed as the fifth argument to sqlite3changeset_apply() may be
9552: ** invoked. A description of exactly when the conflict handler is invoked for
9553: ** each type of change is below.
9554: **
9555: ** Unlike the xFilter argument, xConflict may not be passed NULL. The results
9556: ** of passing anything other than a valid function pointer as the xConflict
9557: ** argument are undefined.
9558: **
9559: ** Each time the conflict handler function is invoked, it must return one
9560: ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
9561: ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
9562: ** if the second argument passed to the conflict handler is either
9563: ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
9564: ** returns an illegal value, any changes already made are rolled back and
9565: ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
9566: ** actions are taken by sqlite3changeset_apply() depending on the value
9567: ** returned by each invocation of the conflict-handler function. Refer to
9568: ** the documentation for the three
9569: ** [SQLITE_CHANGESET_OMIT|available return values] for details.
9570: **
9571: ** <dl>
9572: ** <dt>DELETE Changes<dd>
9573: ** For each DELETE change, this function checks if the target database
9574: ** contains a row with the same primary key value (or values) as the
9575: ** original row values stored in the changeset. If it does, and the values
9576: ** stored in all non-primary key columns also match the values stored in
9577: ** the changeset the row is deleted from the target database.
9578: **
9579: ** If a row with matching primary key values is found, but one or more of
9580: ** the non-primary key fields contains a value different from the original
9581: ** row value stored in the changeset, the conflict-handler function is
1.4.2.1 ! misho 9582: ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
! 9583: ** database table has more columns than are recorded in the changeset,
! 9584: ** only the values of those non-primary key fields are compared against
! 9585: ** the current database contents - any trailing database table columns
! 9586: ** are ignored.
1.4 misho 9587: **
9588: ** If no row with matching primary key values is found in the database,
9589: ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
9590: ** passed as the second argument.
9591: **
9592: ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
9593: ** (which can only happen if a foreign key constraint is violated), the
9594: ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
9595: ** passed as the second argument. This includes the case where the DELETE
9596: ** operation is attempted because an earlier call to the conflict handler
9597: ** function returned [SQLITE_CHANGESET_REPLACE].
9598: **
9599: ** <dt>INSERT Changes<dd>
9600: ** For each INSERT change, an attempt is made to insert the new row into
1.4.2.1 ! misho 9601: ** the database. If the changeset row contains fewer fields than the
! 9602: ** database table, the trailing fields are populated with their default
! 9603: ** values.
1.4 misho 9604: **
9605: ** If the attempt to insert the row fails because the database already
9606: ** contains a row with the same primary key values, the conflict handler
9607: ** function is invoked with the second argument set to
9608: ** [SQLITE_CHANGESET_CONFLICT].
9609: **
9610: ** If the attempt to insert the row fails because of some other constraint
9611: ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
9612: ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
9613: ** This includes the case where the INSERT operation is re-attempted because
9614: ** an earlier call to the conflict handler function returned
9615: ** [SQLITE_CHANGESET_REPLACE].
9616: **
9617: ** <dt>UPDATE Changes<dd>
9618: ** For each UPDATE change, this function checks if the target database
9619: ** contains a row with the same primary key value (or values) as the
9620: ** original row values stored in the changeset. If it does, and the values
1.4.2.1 ! misho 9621: ** stored in all modified non-primary key columns also match the values
! 9622: ** stored in the changeset the row is updated within the target database.
1.4 misho 9623: **
9624: ** If a row with matching primary key values is found, but one or more of
1.4.2.1 ! misho 9625: ** the modified non-primary key fields contains a value different from an
! 9626: ** original row value stored in the changeset, the conflict-handler function
! 9627: ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
1.4 misho 9628: ** UPDATE changes only contain values for non-primary key fields that are
9629: ** to be modified, only those fields need to match the original values to
9630: ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
9631: **
9632: ** If no row with matching primary key values is found in the database,
9633: ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
9634: ** passed as the second argument.
9635: **
9636: ** If the UPDATE operation is attempted, but SQLite returns
9637: ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with
9638: ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
9639: ** This includes the case where the UPDATE operation is attempted after
9640: ** an earlier call to the conflict handler function returned
9641: ** [SQLITE_CHANGESET_REPLACE].
9642: ** </dl>
9643: **
9644: ** It is safe to execute SQL statements, including those that write to the
9645: ** table that the callback related to, from within the xConflict callback.
9646: ** This can be used to further customize the applications conflict
9647: ** resolution strategy.
9648: **
9649: ** All changes made by this function are enclosed in a savepoint transaction.
9650: ** If any other error (aside from a constraint failure when attempting to
9651: ** write to the target database) occurs, then the savepoint transaction is
9652: ** rolled back, restoring the target database to its original state, and an
9653: ** SQLite error code returned.
9654: */
1.4.2.1 ! misho 9655: SQLITE_API int sqlite3changeset_apply(
1.4 misho 9656: sqlite3 *db, /* Apply change to "main" db of this handle */
9657: int nChangeset, /* Size of changeset in bytes */
9658: void *pChangeset, /* Changeset blob */
9659: int(*xFilter)(
9660: void *pCtx, /* Copy of sixth arg to _apply() */
9661: const char *zTab /* Table name */
9662: ),
9663: int(*xConflict)(
9664: void *pCtx, /* Copy of sixth arg to _apply() */
9665: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
9666: sqlite3_changeset_iter *p /* Handle describing change and conflict */
9667: ),
9668: void *pCtx /* First argument passed to xConflict */
9669: );
9670:
9671: /*
9672: ** CAPI3REF: Constants Passed To The Conflict Handler
9673: **
9674: ** Values that may be passed as the second argument to a conflict-handler.
9675: **
9676: ** <dl>
9677: ** <dt>SQLITE_CHANGESET_DATA<dd>
9678: ** The conflict handler is invoked with CHANGESET_DATA as the second argument
9679: ** when processing a DELETE or UPDATE change if a row with the required
9680: ** PRIMARY KEY fields is present in the database, but one or more other
9681: ** (non primary-key) fields modified by the update do not contain the
9682: ** expected "before" values.
9683: **
9684: ** The conflicting row, in this case, is the database row with the matching
9685: ** primary key.
9686: **
9687: ** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
9688: ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second
9689: ** argument when processing a DELETE or UPDATE change if a row with the
9690: ** required PRIMARY KEY fields is not present in the database.
9691: **
9692: ** There is no conflicting row in this case. The results of invoking the
9693: ** sqlite3changeset_conflict() API are undefined.
9694: **
9695: ** <dt>SQLITE_CHANGESET_CONFLICT<dd>
9696: ** CHANGESET_CONFLICT is passed as the second argument to the conflict
9697: ** handler while processing an INSERT change if the operation would result
9698: ** in duplicate primary key values.
9699: **
9700: ** The conflicting row in this case is the database row with the matching
9701: ** primary key.
9702: **
9703: ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
9704: ** If foreign key handling is enabled, and applying a changeset leaves the
9705: ** database in a state containing foreign key violations, the conflict
9706: ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
9707: ** exactly once before the changeset is committed. If the conflict handler
9708: ** returns CHANGESET_OMIT, the changes, including those that caused the
9709: ** foreign key constraint violation, are committed. Or, if it returns
9710: ** CHANGESET_ABORT, the changeset is rolled back.
9711: **
9712: ** No current or conflicting row information is provided. The only function
9713: ** it is possible to call on the supplied sqlite3_changeset_iter handle
9714: ** is sqlite3changeset_fk_conflicts().
9715: **
9716: ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
9717: ** If any other constraint violation occurs while applying a change (i.e.
9718: ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
9719: ** invoked with CHANGESET_CONSTRAINT as the second argument.
9720: **
9721: ** There is no conflicting row in this case. The results of invoking the
9722: ** sqlite3changeset_conflict() API are undefined.
9723: **
9724: ** </dl>
9725: */
9726: #define SQLITE_CHANGESET_DATA 1
9727: #define SQLITE_CHANGESET_NOTFOUND 2
9728: #define SQLITE_CHANGESET_CONFLICT 3
9729: #define SQLITE_CHANGESET_CONSTRAINT 4
9730: #define SQLITE_CHANGESET_FOREIGN_KEY 5
9731:
9732: /*
9733: ** CAPI3REF: Constants Returned By The Conflict Handler
9734: **
9735: ** A conflict handler callback must return one of the following three values.
9736: **
9737: ** <dl>
9738: ** <dt>SQLITE_CHANGESET_OMIT<dd>
9739: ** If a conflict handler returns this value no special action is taken. The
9740: ** change that caused the conflict is not applied. The session module
9741: ** continues to the next change in the changeset.
9742: **
9743: ** <dt>SQLITE_CHANGESET_REPLACE<dd>
9744: ** This value may only be returned if the second argument to the conflict
9745: ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
9746: ** is not the case, any changes applied so far are rolled back and the
9747: ** call to sqlite3changeset_apply() returns SQLITE_MISUSE.
9748: **
9749: ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
9750: ** handler, then the conflicting row is either updated or deleted, depending
9751: ** on the type of change.
9752: **
9753: ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
9754: ** handler, then the conflicting row is removed from the database and a
9755: ** second attempt to apply the change is made. If this second attempt fails,
9756: ** the original row is restored to the database before continuing.
9757: **
9758: ** <dt>SQLITE_CHANGESET_ABORT<dd>
9759: ** If this value is returned, any changes applied so far are rolled back
9760: ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
9761: ** </dl>
9762: */
9763: #define SQLITE_CHANGESET_OMIT 0
9764: #define SQLITE_CHANGESET_REPLACE 1
9765: #define SQLITE_CHANGESET_ABORT 2
9766:
9767: /*
9768: ** CAPI3REF: Streaming Versions of API functions.
9769: **
9770: ** The six streaming API xxx_strm() functions serve similar purposes to the
9771: ** corresponding non-streaming API functions:
9772: **
9773: ** <table border=1 style="margin-left:8ex;margin-right:8ex">
9774: ** <tr><th>Streaming function<th>Non-streaming equivalent</th>
9775: ** <tr><td>sqlite3changeset_apply_str<td>[sqlite3changeset_apply]
9776: ** <tr><td>sqlite3changeset_concat_str<td>[sqlite3changeset_concat]
9777: ** <tr><td>sqlite3changeset_invert_str<td>[sqlite3changeset_invert]
9778: ** <tr><td>sqlite3changeset_start_str<td>[sqlite3changeset_start]
9779: ** <tr><td>sqlite3session_changeset_str<td>[sqlite3session_changeset]
9780: ** <tr><td>sqlite3session_patchset_str<td>[sqlite3session_patchset]
9781: ** </table>
9782: **
9783: ** Non-streaming functions that accept changesets (or patchsets) as input
9784: ** require that the entire changeset be stored in a single buffer in memory.
9785: ** Similarly, those that return a changeset or patchset do so by returning
9786: ** a pointer to a single large buffer allocated using sqlite3_malloc().
9787: ** Normally this is convenient. However, if an application running in a
9788: ** low-memory environment is required to handle very large changesets, the
9789: ** large contiguous memory allocations required can become onerous.
9790: **
9791: ** In order to avoid this problem, instead of a single large buffer, input
9792: ** is passed to a streaming API functions by way of a callback function that
9793: ** the sessions module invokes to incrementally request input data as it is
9794: ** required. In all cases, a pair of API function parameters such as
9795: **
9796: ** <pre>
9797: ** int nChangeset,
9798: ** void *pChangeset,
9799: ** </pre>
9800: **
9801: ** Is replaced by:
9802: **
9803: ** <pre>
9804: ** int (*xInput)(void *pIn, void *pData, int *pnData),
9805: ** void *pIn,
9806: ** </pre>
9807: **
9808: ** Each time the xInput callback is invoked by the sessions module, the first
9809: ** argument passed is a copy of the supplied pIn context pointer. The second
9810: ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
9811: ** error occurs the xInput method should copy up to (*pnData) bytes of data
9812: ** into the buffer and set (*pnData) to the actual number of bytes copied
9813: ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
9814: ** should be set to zero to indicate this. Or, if an error occurs, an SQLite
9815: ** error code should be returned. In all cases, if an xInput callback returns
9816: ** an error, all processing is abandoned and the streaming API function
9817: ** returns a copy of the error code to the caller.
9818: **
9819: ** In the case of sqlite3changeset_start_strm(), the xInput callback may be
9820: ** invoked by the sessions module at any point during the lifetime of the
9821: ** iterator. If such an xInput callback returns an error, the iterator enters
9822: ** an error state, whereby all subsequent calls to iterator functions
9823: ** immediately fail with the same error code as returned by xInput.
9824: **
9825: ** Similarly, streaming API functions that return changesets (or patchsets)
9826: ** return them in chunks by way of a callback function instead of via a
9827: ** pointer to a single large buffer. In this case, a pair of parameters such
9828: ** as:
9829: **
9830: ** <pre>
9831: ** int *pnChangeset,
9832: ** void **ppChangeset,
9833: ** </pre>
9834: **
9835: ** Is replaced by:
9836: **
9837: ** <pre>
9838: ** int (*xOutput)(void *pOut, const void *pData, int nData),
9839: ** void *pOut
9840: ** </pre>
9841: **
9842: ** The xOutput callback is invoked zero or more times to return data to
9843: ** the application. The first parameter passed to each call is a copy of the
9844: ** pOut pointer supplied by the application. The second parameter, pData,
9845: ** points to a buffer nData bytes in size containing the chunk of output
9846: ** data being returned. If the xOutput callback successfully processes the
9847: ** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
9848: ** it should return some other SQLite error code. In this case processing
9849: ** is immediately abandoned and the streaming API function returns a copy
9850: ** of the xOutput error code to the application.
9851: **
9852: ** The sessions module never invokes an xOutput callback with the third
9853: ** parameter set to a value less than or equal to zero. Other than this,
9854: ** no guarantees are made as to the size of the chunks of data returned.
9855: */
1.4.2.1 ! misho 9856: SQLITE_API int sqlite3changeset_apply_strm(
1.4 misho 9857: sqlite3 *db, /* Apply change to "main" db of this handle */
9858: int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
9859: void *pIn, /* First arg for xInput */
9860: int(*xFilter)(
9861: void *pCtx, /* Copy of sixth arg to _apply() */
9862: const char *zTab /* Table name */
9863: ),
9864: int(*xConflict)(
9865: void *pCtx, /* Copy of sixth arg to _apply() */
9866: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
9867: sqlite3_changeset_iter *p /* Handle describing change and conflict */
9868: ),
9869: void *pCtx /* First argument passed to xConflict */
9870: );
1.4.2.1 ! misho 9871: SQLITE_API int sqlite3changeset_concat_strm(
1.4 misho 9872: int (*xInputA)(void *pIn, void *pData, int *pnData),
9873: void *pInA,
9874: int (*xInputB)(void *pIn, void *pData, int *pnData),
9875: void *pInB,
9876: int (*xOutput)(void *pOut, const void *pData, int nData),
9877: void *pOut
9878: );
1.4.2.1 ! misho 9879: SQLITE_API int sqlite3changeset_invert_strm(
1.4 misho 9880: int (*xInput)(void *pIn, void *pData, int *pnData),
9881: void *pIn,
9882: int (*xOutput)(void *pOut, const void *pData, int nData),
9883: void *pOut
9884: );
1.4.2.1 ! misho 9885: SQLITE_API int sqlite3changeset_start_strm(
1.4 misho 9886: sqlite3_changeset_iter **pp,
9887: int (*xInput)(void *pIn, void *pData, int *pnData),
9888: void *pIn
9889: );
1.4.2.1 ! misho 9890: SQLITE_API int sqlite3session_changeset_strm(
1.4 misho 9891: sqlite3_session *pSession,
9892: int (*xOutput)(void *pOut, const void *pData, int nData),
9893: void *pOut
9894: );
1.4.2.1 ! misho 9895: SQLITE_API int sqlite3session_patchset_strm(
1.4 misho 9896: sqlite3_session *pSession,
9897: int (*xOutput)(void *pOut, const void *pData, int nData),
9898: void *pOut
9899: );
1.4.2.1 ! misho 9900: SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
1.4 misho 9901: int (*xInput)(void *pIn, void *pData, int *pnData),
9902: void *pIn
9903: );
1.4.2.1 ! misho 9904: SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
1.4 misho 9905: int (*xOutput)(void *pOut, const void *pData, int nData),
9906: void *pOut
9907: );
9908:
9909:
9910: /*
9911: ** Make sure we can call this stuff from C++.
9912: */
9913: #ifdef __cplusplus
9914: }
9915: #endif
9916:
9917: #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
9918:
9919: /******** End of sqlite3session.h *********/
9920: /******** Begin file fts5.h *********/
9921: /*
9922: ** 2014 May 31
9923: **
9924: ** The author disclaims copyright to this source code. In place of
9925: ** a legal notice, here is a blessing:
9926: **
9927: ** May you do good and not evil.
9928: ** May you find forgiveness for yourself and forgive others.
9929: ** May you share freely, never taking more than you give.
9930: **
9931: ******************************************************************************
9932: **
9933: ** Interfaces to extend FTS5. Using the interfaces defined in this file,
9934: ** FTS5 may be extended with:
9935: **
9936: ** * custom tokenizers, and
9937: ** * custom auxiliary functions.
9938: */
9939:
9940:
9941: #ifndef _FTS5_H
9942: #define _FTS5_H
9943:
9944:
9945: #ifdef __cplusplus
9946: extern "C" {
9947: #endif
9948:
9949: /*************************************************************************
9950: ** CUSTOM AUXILIARY FUNCTIONS
9951: **
9952: ** Virtual table implementations may overload SQL functions by implementing
9953: ** the sqlite3_module.xFindFunction() method.
9954: */
9955:
9956: typedef struct Fts5ExtensionApi Fts5ExtensionApi;
9957: typedef struct Fts5Context Fts5Context;
9958: typedef struct Fts5PhraseIter Fts5PhraseIter;
9959:
9960: typedef void (*fts5_extension_function)(
9961: const Fts5ExtensionApi *pApi, /* API offered by current FTS version */
9962: Fts5Context *pFts, /* First arg to pass to pApi functions */
9963: sqlite3_context *pCtx, /* Context for returning result/error */
9964: int nVal, /* Number of values in apVal[] array */
9965: sqlite3_value **apVal /* Array of trailing arguments */
9966: );
9967:
9968: struct Fts5PhraseIter {
9969: const unsigned char *a;
9970: const unsigned char *b;
9971: };
9972:
9973: /*
9974: ** EXTENSION API FUNCTIONS
9975: **
9976: ** xUserData(pFts):
9977: ** Return a copy of the context pointer the extension function was
9978: ** registered with.
9979: **
9980: ** xColumnTotalSize(pFts, iCol, pnToken):
9981: ** If parameter iCol is less than zero, set output variable *pnToken
9982: ** to the total number of tokens in the FTS5 table. Or, if iCol is
9983: ** non-negative but less than the number of columns in the table, return
9984: ** the total number of tokens in column iCol, considering all rows in
9985: ** the FTS5 table.
9986: **
9987: ** If parameter iCol is greater than or equal to the number of columns
9988: ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
9989: ** an OOM condition or IO error), an appropriate SQLite error code is
9990: ** returned.
9991: **
9992: ** xColumnCount(pFts):
9993: ** Return the number of columns in the table.
9994: **
9995: ** xColumnSize(pFts, iCol, pnToken):
9996: ** If parameter iCol is less than zero, set output variable *pnToken
9997: ** to the total number of tokens in the current row. Or, if iCol is
9998: ** non-negative but less than the number of columns in the table, set
9999: ** *pnToken to the number of tokens in column iCol of the current row.
10000: **
10001: ** If parameter iCol is greater than or equal to the number of columns
10002: ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
10003: ** an OOM condition or IO error), an appropriate SQLite error code is
10004: ** returned.
10005: **
10006: ** This function may be quite inefficient if used with an FTS5 table
10007: ** created with the "columnsize=0" option.
10008: **
10009: ** xColumnText:
10010: ** This function attempts to retrieve the text of column iCol of the
10011: ** current document. If successful, (*pz) is set to point to a buffer
10012: ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes
10013: ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
10014: ** if an error occurs, an SQLite error code is returned and the final values
10015: ** of (*pz) and (*pn) are undefined.
10016: **
10017: ** xPhraseCount:
10018: ** Returns the number of phrases in the current query expression.
10019: **
10020: ** xPhraseSize:
10021: ** Returns the number of tokens in phrase iPhrase of the query. Phrases
10022: ** are numbered starting from zero.
10023: **
10024: ** xInstCount:
10025: ** Set *pnInst to the total number of occurrences of all phrases within
10026: ** the query within the current row. Return SQLITE_OK if successful, or
10027: ** an error code (i.e. SQLITE_NOMEM) if an error occurs.
10028: **
10029: ** This API can be quite slow if used with an FTS5 table created with the
10030: ** "detail=none" or "detail=column" option. If the FTS5 table is created
10031: ** with either "detail=none" or "detail=column" and "content=" option
10032: ** (i.e. if it is a contentless table), then this API always returns 0.
10033: **
10034: ** xInst:
10035: ** Query for the details of phrase match iIdx within the current row.
10036: ** Phrase matches are numbered starting from zero, so the iIdx argument
10037: ** should be greater than or equal to zero and smaller than the value
10038: ** output by xInstCount().
10039: **
10040: ** Usually, output parameter *piPhrase is set to the phrase number, *piCol
10041: ** to the column in which it occurs and *piOff the token offset of the
10042: ** first token of the phrase. The exception is if the table was created
10043: ** with the offsets=0 option specified. In this case *piOff is always
10044: ** set to -1.
10045: **
10046: ** Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM)
10047: ** if an error occurs.
10048: **
10049: ** This API can be quite slow if used with an FTS5 table created with the
10050: ** "detail=none" or "detail=column" option.
10051: **
10052: ** xRowid:
10053: ** Returns the rowid of the current row.
10054: **
10055: ** xTokenize:
10056: ** Tokenize text using the tokenizer belonging to the FTS5 table.
10057: **
10058: ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
10059: ** This API function is used to query the FTS table for phrase iPhrase
10060: ** of the current query. Specifically, a query equivalent to:
10061: **
10062: ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
10063: **
10064: ** with $p set to a phrase equivalent to the phrase iPhrase of the
10065: ** current query is executed. Any column filter that applies to
10066: ** phrase iPhrase of the current query is included in $p. For each
10067: ** row visited, the callback function passed as the fourth argument
10068: ** is invoked. The context and API objects passed to the callback
10069: ** function may be used to access the properties of each matched row.
10070: ** Invoking Api.xUserData() returns a copy of the pointer passed as
10071: ** the third argument to pUserData.
10072: **
10073: ** If the callback function returns any value other than SQLITE_OK, the
10074: ** query is abandoned and the xQueryPhrase function returns immediately.
10075: ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
10076: ** Otherwise, the error code is propagated upwards.
10077: **
10078: ** If the query runs to completion without incident, SQLITE_OK is returned.
10079: ** Or, if some error occurs before the query completes or is aborted by
10080: ** the callback, an SQLite error code is returned.
10081: **
10082: **
10083: ** xSetAuxdata(pFts5, pAux, xDelete)
10084: **
10085: ** Save the pointer passed as the second argument as the extension functions
10086: ** "auxiliary data". The pointer may then be retrieved by the current or any
10087: ** future invocation of the same fts5 extension function made as part of
10088: ** of the same MATCH query using the xGetAuxdata() API.
10089: **
10090: ** Each extension function is allocated a single auxiliary data slot for
10091: ** each FTS query (MATCH expression). If the extension function is invoked
10092: ** more than once for a single FTS query, then all invocations share a
10093: ** single auxiliary data context.
10094: **
10095: ** If there is already an auxiliary data pointer when this function is
10096: ** invoked, then it is replaced by the new pointer. If an xDelete callback
10097: ** was specified along with the original pointer, it is invoked at this
10098: ** point.
10099: **
10100: ** The xDelete callback, if one is specified, is also invoked on the
10101: ** auxiliary data pointer after the FTS5 query has finished.
10102: **
10103: ** If an error (e.g. an OOM condition) occurs within this function, an
10104: ** the auxiliary data is set to NULL and an error code returned. If the
10105: ** xDelete parameter was not NULL, it is invoked on the auxiliary data
10106: ** pointer before returning.
10107: **
10108: **
10109: ** xGetAuxdata(pFts5, bClear)
10110: **
10111: ** Returns the current auxiliary data pointer for the fts5 extension
10112: ** function. See the xSetAuxdata() method for details.
10113: **
10114: ** If the bClear argument is non-zero, then the auxiliary data is cleared
10115: ** (set to NULL) before this function returns. In this case the xDelete,
10116: ** if any, is not invoked.
10117: **
10118: **
10119: ** xRowCount(pFts5, pnRow)
10120: **
10121: ** This function is used to retrieve the total number of rows in the table.
10122: ** In other words, the same value that would be returned by:
10123: **
10124: ** SELECT count(*) FROM ftstable;
10125: **
10126: ** xPhraseFirst()
10127: ** This function is used, along with type Fts5PhraseIter and the xPhraseNext
10128: ** method, to iterate through all instances of a single query phrase within
10129: ** the current row. This is the same information as is accessible via the
10130: ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
10131: ** to use, this API may be faster under some circumstances. To iterate
10132: ** through instances of phrase iPhrase, use the following code:
10133: **
10134: ** Fts5PhraseIter iter;
10135: ** int iCol, iOff;
10136: ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
10137: ** iCol>=0;
10138: ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
10139: ** ){
10140: ** // An instance of phrase iPhrase at offset iOff of column iCol
10141: ** }
10142: **
10143: ** The Fts5PhraseIter structure is defined above. Applications should not
10144: ** modify this structure directly - it should only be used as shown above
10145: ** with the xPhraseFirst() and xPhraseNext() API methods (and by
10146: ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
10147: **
10148: ** This API can be quite slow if used with an FTS5 table created with the
10149: ** "detail=none" or "detail=column" option. If the FTS5 table is created
10150: ** with either "detail=none" or "detail=column" and "content=" option
10151: ** (i.e. if it is a contentless table), then this API always iterates
10152: ** through an empty set (all calls to xPhraseFirst() set iCol to -1).
10153: **
10154: ** xPhraseNext()
10155: ** See xPhraseFirst above.
10156: **
10157: ** xPhraseFirstColumn()
10158: ** This function and xPhraseNextColumn() are similar to the xPhraseFirst()
10159: ** and xPhraseNext() APIs described above. The difference is that instead
10160: ** of iterating through all instances of a phrase in the current row, these
10161: ** APIs are used to iterate through the set of columns in the current row
10162: ** that contain one or more instances of a specified phrase. For example:
10163: **
10164: ** Fts5PhraseIter iter;
10165: ** int iCol;
10166: ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
10167: ** iCol>=0;
10168: ** pApi->xPhraseNextColumn(pFts, &iter, &iCol)
10169: ** ){
10170: ** // Column iCol contains at least one instance of phrase iPhrase
10171: ** }
10172: **
10173: ** This API can be quite slow if used with an FTS5 table created with the
10174: ** "detail=none" option. If the FTS5 table is created with either
10175: ** "detail=none" "content=" option (i.e. if it is a contentless table),
10176: ** then this API always iterates through an empty set (all calls to
10177: ** xPhraseFirstColumn() set iCol to -1).
10178: **
10179: ** The information accessed using this API and its companion
10180: ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
10181: ** (or xInst/xInstCount). The chief advantage of this API is that it is
10182: ** significantly more efficient than those alternatives when used with
10183: ** "detail=column" tables.
10184: **
10185: ** xPhraseNextColumn()
10186: ** See xPhraseFirstColumn above.
10187: */
10188: struct Fts5ExtensionApi {
10189: int iVersion; /* Currently always set to 3 */
10190:
10191: void *(*xUserData)(Fts5Context*);
10192:
10193: int (*xColumnCount)(Fts5Context*);
10194: int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
10195: int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
10196:
10197: int (*xTokenize)(Fts5Context*,
10198: const char *pText, int nText, /* Text to tokenize */
10199: void *pCtx, /* Context passed to xToken() */
10200: int (*xToken)(void*, int, const char*, int, int, int) /* Callback */
10201: );
10202:
10203: int (*xPhraseCount)(Fts5Context*);
10204: int (*xPhraseSize)(Fts5Context*, int iPhrase);
10205:
10206: int (*xInstCount)(Fts5Context*, int *pnInst);
10207: int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
10208:
10209: sqlite3_int64 (*xRowid)(Fts5Context*);
10210: int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
10211: int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
10212:
10213: int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
10214: int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
10215: );
10216: int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
10217: void *(*xGetAuxdata)(Fts5Context*, int bClear);
10218:
10219: int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
10220: void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
10221:
10222: int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
10223: void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
10224: };
10225:
10226: /*
10227: ** CUSTOM AUXILIARY FUNCTIONS
10228: *************************************************************************/
10229:
10230: /*************************************************************************
10231: ** CUSTOM TOKENIZERS
10232: **
10233: ** Applications may also register custom tokenizer types. A tokenizer
10234: ** is registered by providing fts5 with a populated instance of the
10235: ** following structure. All structure methods must be defined, setting
10236: ** any member of the fts5_tokenizer struct to NULL leads to undefined
10237: ** behaviour. The structure methods are expected to function as follows:
10238: **
10239: ** xCreate:
10240: ** This function is used to allocate and initialize a tokenizer instance.
10241: ** A tokenizer instance is required to actually tokenize text.
10242: **
10243: ** The first argument passed to this function is a copy of the (void*)
10244: ** pointer provided by the application when the fts5_tokenizer object
10245: ** was registered with FTS5 (the third argument to xCreateTokenizer()).
10246: ** The second and third arguments are an array of nul-terminated strings
10247: ** containing the tokenizer arguments, if any, specified following the
10248: ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used
10249: ** to create the FTS5 table.
10250: **
10251: ** The final argument is an output variable. If successful, (*ppOut)
10252: ** should be set to point to the new tokenizer handle and SQLITE_OK
10253: ** returned. If an error occurs, some value other than SQLITE_OK should
10254: ** be returned. In this case, fts5 assumes that the final value of *ppOut
10255: ** is undefined.
10256: **
10257: ** xDelete:
10258: ** This function is invoked to delete a tokenizer handle previously
10259: ** allocated using xCreate(). Fts5 guarantees that this function will
10260: ** be invoked exactly once for each successful call to xCreate().
10261: **
10262: ** xTokenize:
10263: ** This function is expected to tokenize the nText byte string indicated
10264: ** by argument pText. pText may or may not be nul-terminated. The first
10265: ** argument passed to this function is a pointer to an Fts5Tokenizer object
10266: ** returned by an earlier call to xCreate().
10267: **
10268: ** The second argument indicates the reason that FTS5 is requesting
10269: ** tokenization of the supplied text. This is always one of the following
10270: ** four values:
10271: **
10272: ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
10273: ** or removed from the FTS table. The tokenizer is being invoked to
10274: ** determine the set of tokens to add to (or delete from) the
10275: ** FTS index.
10276: **
10277: ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
10278: ** against the FTS index. The tokenizer is being called to tokenize
10279: ** a bareword or quoted string specified as part of the query.
10280: **
10281: ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
10282: ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
10283: ** followed by a "*" character, indicating that the last token
10284: ** returned by the tokenizer will be treated as a token prefix.
10285: **
10286: ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
10287: ** satisfy an fts5_api.xTokenize() request made by an auxiliary
10288: ** function. Or an fts5_api.xColumnSize() request made by the same
10289: ** on a columnsize=0 database.
10290: ** </ul>
10291: **
10292: ** For each token in the input string, the supplied callback xToken() must
10293: ** be invoked. The first argument to it should be a copy of the pointer
10294: ** passed as the second argument to xTokenize(). The third and fourth
10295: ** arguments are a pointer to a buffer containing the token text, and the
10296: ** size of the token in bytes. The 4th and 5th arguments are the byte offsets
10297: ** of the first byte of and first byte immediately following the text from
10298: ** which the token is derived within the input.
10299: **
10300: ** The second argument passed to the xToken() callback ("tflags") should
10301: ** normally be set to 0. The exception is if the tokenizer supports
10302: ** synonyms. In this case see the discussion below for details.
10303: **
10304: ** FTS5 assumes the xToken() callback is invoked for each token in the
10305: ** order that they occur within the input text.
10306: **
10307: ** If an xToken() callback returns any value other than SQLITE_OK, then
10308: ** the tokenization should be abandoned and the xTokenize() method should
10309: ** immediately return a copy of the xToken() return value. Or, if the
10310: ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
10311: ** if an error occurs with the xTokenize() implementation itself, it
10312: ** may abandon the tokenization and return any error code other than
10313: ** SQLITE_OK or SQLITE_DONE.
10314: **
10315: ** SYNONYM SUPPORT
10316: **
10317: ** Custom tokenizers may also support synonyms. Consider a case in which a
10318: ** user wishes to query for a phrase such as "first place". Using the
10319: ** built-in tokenizers, the FTS5 query 'first + place' will match instances
10320: ** of "first place" within the document set, but not alternative forms
10321: ** such as "1st place". In some applications, it would be better to match
10322: ** all instances of "first place" or "1st place" regardless of which form
10323: ** the user specified in the MATCH query text.
10324: **
10325: ** There are several ways to approach this in FTS5:
10326: **
10327: ** <ol><li> By mapping all synonyms to a single token. In this case, the
10328: ** In the above example, this means that the tokenizer returns the
10329: ** same token for inputs "first" and "1st". Say that token is in
10330: ** fact "first", so that when the user inserts the document "I won
10331: ** 1st place" entries are added to the index for tokens "i", "won",
10332: ** "first" and "place". If the user then queries for '1st + place',
10333: ** the tokenizer substitutes "first" for "1st" and the query works
10334: ** as expected.
10335: **
10336: ** <li> By adding multiple synonyms for a single term to the FTS index.
10337: ** In this case, when tokenizing query text, the tokenizer may
10338: ** provide multiple synonyms for a single term within the document.
10339: ** FTS5 then queries the index for each synonym individually. For
10340: ** example, faced with the query:
10341: **
10342: ** <codeblock>
10343: ** ... MATCH 'first place'</codeblock>
10344: **
10345: ** the tokenizer offers both "1st" and "first" as synonyms for the
10346: ** first token in the MATCH query and FTS5 effectively runs a query
10347: ** similar to:
10348: **
10349: ** <codeblock>
10350: ** ... MATCH '(first OR 1st) place'</codeblock>
10351: **
10352: ** except that, for the purposes of auxiliary functions, the query
10353: ** still appears to contain just two phrases - "(first OR 1st)"
10354: ** being treated as a single phrase.
10355: **
10356: ** <li> By adding multiple synonyms for a single term to the FTS index.
10357: ** Using this method, when tokenizing document text, the tokenizer
10358: ** provides multiple synonyms for each token. So that when a
10359: ** document such as "I won first place" is tokenized, entries are
10360: ** added to the FTS index for "i", "won", "first", "1st" and
10361: ** "place".
10362: **
10363: ** This way, even if the tokenizer does not provide synonyms
10364: ** when tokenizing query text (it should not - to do would be
10365: ** inefficient), it doesn't matter if the user queries for
10366: ** 'first + place' or '1st + place', as there are entires in the
10367: ** FTS index corresponding to both forms of the first token.
10368: ** </ol>
10369: **
10370: ** Whether it is parsing document or query text, any call to xToken that
10371: ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
10372: ** is considered to supply a synonym for the previous token. For example,
10373: ** when parsing the document "I won first place", a tokenizer that supports
10374: ** synonyms would call xToken() 5 times, as follows:
10375: **
10376: ** <codeblock>
10377: ** xToken(pCtx, 0, "i", 1, 0, 1);
10378: ** xToken(pCtx, 0, "won", 3, 2, 5);
10379: ** xToken(pCtx, 0, "first", 5, 6, 11);
10380: ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11);
10381: ** xToken(pCtx, 0, "place", 5, 12, 17);
10382: **</codeblock>
10383: **
10384: ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
10385: ** xToken() is called. Multiple synonyms may be specified for a single token
10386: ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
10387: ** There is no limit to the number of synonyms that may be provided for a
10388: ** single token.
10389: **
10390: ** In many cases, method (1) above is the best approach. It does not add
10391: ** extra data to the FTS index or require FTS5 to query for multiple terms,
10392: ** so it is efficient in terms of disk space and query speed. However, it
10393: ** does not support prefix queries very well. If, as suggested above, the
10394: ** token "first" is subsituted for "1st" by the tokenizer, then the query:
10395: **
10396: ** <codeblock>
10397: ** ... MATCH '1s*'</codeblock>
10398: **
10399: ** will not match documents that contain the token "1st" (as the tokenizer
10400: ** will probably not map "1s" to any prefix of "first").
10401: **
10402: ** For full prefix support, method (3) may be preferred. In this case,
10403: ** because the index contains entries for both "first" and "1st", prefix
10404: ** queries such as 'fi*' or '1s*' will match correctly. However, because
10405: ** extra entries are added to the FTS index, this method uses more space
10406: ** within the database.
10407: **
10408: ** Method (2) offers a midpoint between (1) and (3). Using this method,
10409: ** a query such as '1s*' will match documents that contain the literal
10410: ** token "1st", but not "first" (assuming the tokenizer is not able to
10411: ** provide synonyms for prefixes). However, a non-prefix query like '1st'
10412: ** will match against "1st" and "first". This method does not require
10413: ** extra disk space, as no extra entries are added to the FTS index.
10414: ** On the other hand, it may require more CPU cycles to run MATCH queries,
10415: ** as separate queries of the FTS index are required for each synonym.
10416: **
10417: ** When using methods (2) or (3), it is important that the tokenizer only
10418: ** provide synonyms when tokenizing document text (method (2)) or query
10419: ** text (method (3)), not both. Doing so will not cause any errors, but is
10420: ** inefficient.
10421: */
10422: typedef struct Fts5Tokenizer Fts5Tokenizer;
10423: typedef struct fts5_tokenizer fts5_tokenizer;
10424: struct fts5_tokenizer {
10425: int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
10426: void (*xDelete)(Fts5Tokenizer*);
10427: int (*xTokenize)(Fts5Tokenizer*,
10428: void *pCtx,
10429: int flags, /* Mask of FTS5_TOKENIZE_* flags */
10430: const char *pText, int nText,
10431: int (*xToken)(
10432: void *pCtx, /* Copy of 2nd argument to xTokenize() */
10433: int tflags, /* Mask of FTS5_TOKEN_* flags */
10434: const char *pToken, /* Pointer to buffer containing token */
10435: int nToken, /* Size of token in bytes */
10436: int iStart, /* Byte offset of token within input text */
10437: int iEnd /* Byte offset of end of token within input text */
10438: )
10439: );
10440: };
10441:
10442: /* Flags that may be passed as the third argument to xTokenize() */
10443: #define FTS5_TOKENIZE_QUERY 0x0001
10444: #define FTS5_TOKENIZE_PREFIX 0x0002
10445: #define FTS5_TOKENIZE_DOCUMENT 0x0004
10446: #define FTS5_TOKENIZE_AUX 0x0008
10447:
10448: /* Flags that may be passed by the tokenizer implementation back to FTS5
10449: ** as the third argument to the supplied xToken callback. */
10450: #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */
10451:
10452: /*
10453: ** END OF CUSTOM TOKENIZERS
10454: *************************************************************************/
10455:
10456: /*************************************************************************
10457: ** FTS5 EXTENSION REGISTRATION API
10458: */
10459: typedef struct fts5_api fts5_api;
10460: struct fts5_api {
10461: int iVersion; /* Currently always set to 2 */
10462:
10463: /* Create a new tokenizer */
10464: int (*xCreateTokenizer)(
10465: fts5_api *pApi,
10466: const char *zName,
10467: void *pContext,
10468: fts5_tokenizer *pTokenizer,
10469: void (*xDestroy)(void*)
10470: );
10471:
10472: /* Find an existing tokenizer */
10473: int (*xFindTokenizer)(
10474: fts5_api *pApi,
10475: const char *zName,
10476: void **ppContext,
10477: fts5_tokenizer *pTokenizer
10478: );
10479:
10480: /* Create a new auxiliary function */
10481: int (*xCreateFunction)(
10482: fts5_api *pApi,
10483: const char *zName,
10484: void *pContext,
10485: fts5_extension_function xFunction,
10486: void (*xDestroy)(void*)
10487: );
10488: };
10489:
10490: /*
10491: ** END OF REGISTRATION API
10492: *************************************************************************/
10493:
10494: #ifdef __cplusplus
10495: } /* end of the 'extern "C"' block */
10496: #endif
10497:
10498: #endif /* _FTS5_H */
10499:
10500: /******** End of fts5.h *********/
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