diff options
Diffstat (limited to 'src/sqlite.h.in')
| -rw-r--r-- | src/sqlite.h.in | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/src/sqlite.h.in b/src/sqlite.h.in index 4435925de..f20d457e3 100644 --- a/src/sqlite.h.in +++ b/src/sqlite.h.in @@ -6407,6 +6407,72 @@ void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); /* +** CAPI3REF: Autovacuum Compaction Amount Callback +** METHOD: sqlite3 +** +** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback +** function C that is invoked prior to each autovacuum of the database +** file. ^The callback is passed a copy of the generic data pointer (P), +** the schema-name of the attached database that is being autovacuumed, +** the the size of the database file in pages, the number of free pages, +** and the number of bytes per page, respectively. The callback should +** return the number of free pages that should be removed by the +** autovacuum. ^If the callback returns zero, then no autovacuum happens. +** ^If the value returned is greater than or equal to the number of +** free pages, then a complete autovacuum happens. +** +** <p>^If there are multiple ATTACH-ed database files that are being +** modified as part of a transaction commit, then the autovacuum pages +** callback is invoked separately for each file. +** +** <p><b>The callback is not reentrant.</b> The callback function should +** not attempt to invoke any other SQLite interface. If it does, bad +** things may happen, including segmentation faults and corrupt database +** files. The callback function should be a simple function that +** does some arithmetic on its input parameters and returns a result. +** +** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional +** destructor for the P parameter. ^If X is not NULL, then X(P) is +** invoked whenever the database connection closes or when the callback +** is overwritten by another invocation of sqlite3_autovacuum_pages(). +** +** <p>^There is only one autovacuum pages callback per database connection. +** ^Each call to the sqlite3_autovacuum_pages() interface overrides all +** previous invocations for that database connection. ^If the callback +** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer, +** then the autovacuum steps callback is cancelled. The return value +** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might +** be some other error code if something goes wrong. The current +** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other +** return codes might be added in future releases. +** +** <p>If no autovacuum pages callback is specified (the usual case) or +** a NULL pointer is provided for the callback, +** then the default behavior is to vacuum all free pages. So, in other +** words, the default behavior is the same as if the callback function +** were something like this: +** +** <blockquote><pre> +** unsigned int demonstration_autovac_pages_callback( +** void *pClientData, +** const char *zSchema, +** unsigned int nDbPage, +** unsigned int nFreePage, +** unsigned int nBytePerPage +** ){ +** return nFreePage; +** } +** </pre></blockquote> +*/ +int sqlite3_autovacuum_pages( + sqlite3 *db, + unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int), + void*, + void(*)(void*) +); + + +/* ** CAPI3REF: Data Change Notification Callbacks ** METHOD: sqlite3 ** |