sqlite.h.in

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/*
** CAPI3REF: Formatted String Printing Functions
**
** These routines are workalikes of the "printf()" family of functions
** from the standard C library.
**
** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
** results into memory obtained from [sqlite_malloc()].
** The strings returned by these two routines should be
** released by [sqlite3_free()].  Both routines return a
** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
** memory to hold the resulting string.
**
** In sqlite3_snprintf() routine is similar to "snprintf()" from
** the standard C library.  The result is written into the
** buffer supplied as the second parameter whose size is given by
** the first parameter.  Note that the order of the
** first two parameters is reversed from snprintf().  This is an
** historical accident that cannot be fixed without breaking
** backwards compatibility.  Note also that sqlite3_snprintf()
** returns a pointer to its buffer instead of the number of
** characters actually written into the buffer.  We admit that
** the number of characters written would be a more useful return
** value but we cannot change the implementation of sqlite3_snprintf()
** now without breaking compatibility.
**
** As long as the buffer size is greater than zero, sqlite3_snprintf()
** guarantees that the buffer is always zero-terminated.  The first
** parameter "n" is the total size of the buffer, including space for
** the zero terminator.  So the longest string that can be completely
** written will be n-1 characters.
**
** These routines all implement some additional formatting
** options that are useful for constructing SQL statements.
** All of the usual printf formatting options apply.  In addition, there
** is are "%q" and "%Q" options.
**
** The %q option works like %s in that it substitutes a null-terminated
** string from the argument list.  But %q also doubles every '\'' character.
** %q is designed for use inside a string literal.  By doubling each '\''
** character it escapes that character and allows it to be inserted into
** the string.
**
** For example, so some string variable contains text as follows:
**
** <blockquote><pre>
**  char *zText = "It's a happy day!";
** </pre></blockquote>
**
** One can use this text in an SQL statement as follows:
**
** <blockquote><pre>
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
**  sqlite3_exec(db, zSQL, 0, 0, 0);
**  sqlite3_free(zSQL);
** </pre></blockquote>
**
** Because the %q format string is used, the '\'' character in zText
** is escaped and the SQL generated is as follows:
**
** <blockquote><pre>
**  INSERT INTO table1 VALUES('It''s a happy day!')
** </pre></blockquote>
**
** This is correct.  Had we used %s instead of %q, the generated SQL
** would have looked like this:
**
** <blockquote><pre>
**  INSERT INTO table1 VALUES('It's a happy day!');
** </pre></blockquote>
**
** This second example is an SQL syntax error.  As a general rule you
** should always use %q instead of %s when inserting text into a string 
** literal.
**
** The %Q option works like %q except it also adds single quotes around
** the outside of the total string.  Or if the parameter in the argument
** list is a NULL pointer, %Q substitutes the text "NULL" (without single
** quotes) in place of the %Q option.  So, for example, one could say:
**
** <blockquote><pre>
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
**  sqlite3_exec(db, zSQL, 0, 0, 0);
**  sqlite3_free(zSQL);
** </pre></blockquote>
**
** The code above will render a correct SQL statement in the zSQL
** variable even if the zText variable is a NULL pointer.
*/
char *sqlite3_mprintf(const char*,...);
char *sqlite3_vmprintf(const char*, va_list);
char *sqlite3_snprintf(int,char*,const char*, ...);

/*
** CAPI3REF: Memory Allocation Functions
**
** SQLite uses its own memory allocator.  On some installations, this
** memory allocator is identical to the standard malloc()/realloc()/free()
** and can be used interchangable.  On others, the implementations are
** different.  For maximum portability, it is best not to mix calls
** to the standard malloc/realloc/free with the sqlite versions.
*/
void *sqlite3_malloc(int);
void *sqlite3_realloc(void*, int);
void sqlite3_free(void*);

/*
** CAPI3REF: Compile-Time Authorization Callbacks
***
** This routine registers a authorizer callback with the SQLite library.  
** The authorizer callback is invoked as SQL statements are being compiled
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  At various
** points during the compilation process, as logic is being created
** to perform various actions, the authorizer callback is invoked to
** see if those actions are allowed.  The authorizer callback should
** return SQLITE_OK to allow the action, [SQLITE_IGNORE] to disallow the
** specific action but allow the SQL statement to continue to be
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
** rejected with an error.  
**
** Depending on the action, the [SQLITE_IGNORE] and [SQLITE_DENY] return
** codes might mean something different or they might mean the same
** thing.  If the action is, for example, to perform a delete opertion,
** then [SQLITE_IGNORE] and [SQLITE_DENY] both cause the statement compilation
** to fail with an error.  But if the action is to read a specific column
** from a specific table, then [SQLITE_DENY] will cause the entire
** statement to fail but [SQLITE_IGNORE] will cause a NULL value to be
** read instead of the actual column value.
**
** The first parameter to the authorizer callback is a copy of
** the third parameter to the sqlite3_set_authorizer() interface.
** The second parameter to the callback is an integer 
** [SQLITE_COPY | action code] that specifies the particular action
** to be authorized.  The available action codes are
** [SQLITE_COPY | documented separately].  The third through sixth
** parameters to the callback are strings that contain additional
** details about the action to be authorized.
**
** An authorizer is used when preparing SQL statements from an untrusted
** source, to ensure that the SQL statements do not try to access data
** that they are not allowed to see, or that they do not try to
** execute malicious statements that damage the database.  For
** example, an application may allow a user to enter arbitrary
** SQL queries for evaluation by a database.  But the application does
** not want the user to be able to make arbitrary changes to the
** database.  An authorizer could then be put in place while the
** user-entered SQL is being prepared that disallows everything
** except SELECT statements.  
**
** Only a single authorizer can be in place on a database connection
** at a time.  Each call to sqlite3_set_authorizer overrides the
** previous call.  A NULL authorizer means that no authorization
** callback is invoked.  The default authorizer is NULL.
**
** Note that the authorizer callback is invoked only during 
** [sqlite3_prepare()] or its variants.  Authorization is not
** performed during statement evaluation in [sqlite3_step()].
*/
int sqlite3_set_authorizer(
  sqlite3*,
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
  void *pUserData
);

/*
** CAPI3REF: Authorizer Return Codes
**
** The [sqlite3_set_authorizer | authorizer callback function] must
** return either [SQLITE_OK] or one of these two constants in order
** to signal SQLite whether or not the action is permitted.  See the
** [sqlite3_set_authorizer | authorizer documentation] for additional
** information.
*/
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */

/*
** CAPI3REF: Authorizer Action Codes
**
** The [sqlite3_set_authorizer()] interface registers a callback function
** that is invoked to authorizer certain SQL statement actions.  The
** second parameter to the callback is an integer code that specifies
** what action is being authorized.  These are the integer action codes that
** the authorizer callback may be passed.
**
** These action code values signify what kind of operation is to be 
** authorized.  The 3rd and 4th parameters to the authorization callback
** function will be parameters or NULL depending on which of these
** codes is used as the second parameter.  The 5th parameter to the
** authorizer callback is the name of the database ("main", "temp", 
** etc.) if applicable.  The 6th parameter to the authorizer callback
** is the name of the inner-most trigger or view that is responsible for
** the access attempt or NULL if this access attempt is directly from 
** top-level SQL code.
*/
/******************************************* 3rd ************ 4th ***********/
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
#define SQLITE_DELETE                9   /* Table Name      NULL            */
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
#define SQLITE_INSERT               18   /* Table Name      NULL            */
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
#define SQLITE_READ                 20   /* Table Name      Column Name     */
#define SQLITE_SELECT               21   /* NULL            NULL            */
#define SQLITE_TRANSACTION          22   /* NULL            NULL            */
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
#define SQLITE_ATTACH               24   /* Filename        NULL            */
#define SQLITE_DETACH               25   /* Database Name   NULL            */
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
#define SQLITE_REINDEX              27   /* Index Name      NULL            */
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
#define SQLITE_FUNCTION             31   /* Function Name   NULL            */
#define SQLITE_COPY                  0   /* No longer used */

/*
** CAPI3REF: Tracing And Profiling Functions
**
** These routines register callback functions that can be used for
** tracing and profiling the execution of SQL statements.
** The callback function registered by sqlite3_trace() is invoked
** at the first [sqlite3_step()] for the evaluation of an SQL statement.
** The callback function registered by sqlite3_profile() is invoked
** as each SQL statement finishes and includes
** information on how long that statement ran.
**
** The sqlite3_profile() API is currently considered experimental and
** is subject to change.
*/
void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
void *sqlite3_profile(sqlite3*,
   void(*xProfile)(void*,const char*,sqlite_uint64), void*);

/*
** CAPI3REF: Query Progress Callbacks
**
** This routine configures a callback function - the progress callback - that
** is invoked periodically during long running calls to [sqlite3_exec()],
** [sqlite3_step()] and [sqlite3_get_table()].  An example use for this 
** interface is to keep a GUI updated during a large query.
**
** The progress callback is invoked once for every N virtual machine opcodes,
** where N is the second argument to this function. The progress callback
** itself is identified by the third argument to this function. The fourth
** argument to this function is a void pointer passed to the progress callback
** function each time it is invoked.
**
** If a call to [sqlite3_exec()], [sqlite3_step()], or [sqlite3_get_table()]
** results in fewer than N opcodes being executed, then the progress 
** callback is never invoked.
** 
** Only a single progress callback function may be registered for each
** open database connection.  Every call to sqlite3_progress_handler()
** overwrites the results of the previous call.
** To remove the progress callback altogether, pass NULL as the third
** argument to this function.
**
** If the progress callback returns a result other than 0, then the current 
** query is immediately terminated and any database changes rolled back.
** The containing [sqlite3_exec()], [sqlite3_step()], or
** [sqlite3_get_table()] call returns SQLITE_INTERRUPT.   This feature
** can be used, for example, to implement the "Cancel" button on a
** progress dialog box in a GUI.
*/
void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);

/*
** CAPI3REF: Opening A New Database Connection
**
** Open the sqlite database file "filename".  The "filename" is UTF-8
** encoded for sqlite3_open() and UTF-16 encoded in the native byte order
** for sqlite3_open16().  An [sqlite3*] handle is returned in *ppDb, even
** if an error occurs. If the database is opened (or created) successfully,
** then SQLITE_OK is returned. Otherwise an error code is returned. The
** sqlite3_errmsg() or sqlite3_errmsg16()  routines can be used to obtain