/* ** 2001 September 15 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* ** This header file defines the interface that the sqlite page cache ** subsystem. The page cache subsystem reads and writes a file a page ** at a time and provides a journal for rollback. ** ** @(#) $Id: pager.h,v 1.23 2003/04/25 13:22:53 drh Exp $ */ /* ** The size of one page ** ** You can change this value to another (reasonable) power of two ** such as 512, 2048, 4096, or 8192 and things will still work. But ** experiments show that a page size of 1024 gives the best speed. ** (The speed differences are minimal.) */ #define SQLITE_PAGE_SIZE 1024 /* ** Maximum number of pages in one database. (This is a limitation of ** imposed by 4GB files size limits.) */ #define SQLITE_MAX_PAGE 1073741823 /* ** The type used to represent a page number. The first page in a file ** is called page 1. 0 is used to represent "not a page". */ typedef unsigned int Pgno; /* ** Each open file is managed by a separate instance of the "Pager" structure. */ typedef struct Pager Pager; /* ** See source code comments for a detailed description of the following ** routines: */ int sqlitepager_open(Pager **ppPager, const char *zFilename, int nPage, int nExtra, int useJournal); void sqlitepager_set_destructor(Pager*, void(*)(void*)); void sqlitepager_set_cachesize(Pager*, int); int sqlitepager_close(Pager *pPager); int sqlitepager_get(Pager *pPager, Pgno pgno, void **ppPage); void *sqlitepager_lookup(Pager *pPager, Pgno pgno); int sqlitepager_ref(void*); int sqlitepager_unref(void*); Pgno sqlitepager_pagenumber(void*); int sqlitepager_write(void*); int sqlitepager_iswriteable(void*); int sqlitepager_overwrite(Pager *pPager, Pgno pgno, void*); int sqlitepager_pagecount(Pager*); int sqlitepager_truncate(Pager*,Pgno); int sqlitepager_begin(void*); int sqlitepager_commit(Pager*); int sqlitepager_rollback(Pager*); int sqlitepager_isreadonly(Pager*); int sqlitepager_ckpt_begin(Pager*); int sqlitepager_ckpt_commit(Pager*); int sqlitepager_ckpt_rollback(Pager*); void sqlitepager_dont_rollback(void*); void sqlitepager_dont_write(Pager*, Pgno); int *sqlitepager_stats(Pager*); void sqlitepager_set_safety_level(Pager*,int); const char *sqlitepager_filename(Pager*); int sqlitepager_rename(Pager*, const char *zNewName); #ifdef SQLITE_TEST void sqlitepager_refdump(Pager*); int pager_refinfo_enable; int journal_format; #endif