/*
** 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 1.1 2005/04/04 15:59:32 kommer Exp $
*/
/*
** The default size of a database page.
*/
#ifndef SQLITE_DEFAULT_PAGE_SIZE
# define SQLITE_DEFAULT_PAGE_SIZE 1024
#endif
/* Maximum page size. The upper bound on this value is 65536 (a limit
** imposed by the 2-byte size of cell array pointers.) The
** maximum page size determines the amount of stack space allocated
** by many of the routines in pager.c and btree.c On embedded architectures
** or any machine where memory and especially stack memory is limited,
** one may wish to chose a smaller value for the maximum page size.
*/
#ifndef SQLITE_MAX_PAGE_SIZE
# define SQLITE_MAX_PAGE_SIZE 8192
#endif
/*
** Maximum number of pages in one database.
*/
#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;
/*
** Allowed values for the flags parameter to sqlite3pager_open().
**
** NOTE: This values must match the corresponding BTREE_ values in btree.h.
*/
#define PAGER_OMIT_JOURNAL 0x0001 /* Do not use a rollback journal */
#define PAGER_NO_READLOCK 0x0002 /* Omit readlocks on readonly files */
/*
** See source code comments for a detailed description of the following
** routines:
*/
int sqlite3pager_open(Pager **ppPager, const char *zFilename,
int nExtra, int flags);
void sqlite3pager_set_busyhandler(Pager*, BusyHandler *pBusyHandler);
void sqlite3pager_set_destructor(Pager*, void(*)(void*,int));
void sqlite3pager_set_reiniter(Pager*, void(*)(void*,int));
void sqlite3pager_set_pagesize(Pager*, int);
void sqlite3pager_read_fileheader(Pager*, int, unsigned char*);
void sqlite3pager_set_cachesize(Pager*, int);
int sqlite3pager_close(Pager *pPager);
int sqlite3pager_get(Pager *pPager, Pgno pgno, void **ppPage);
void *sqlite3pager_lookup(Pager *pPager, Pgno pgno);
int sqlite3pager_ref(void*);
int sqlite3pager_unref(void*);
Pgno sqlite3pager_pagenumber(void*);
int sqlite3pager_write(void*);
int sqlite3pager_iswriteable(void*);
int sqlite3pager_overwrite(Pager *pPager, Pgno pgno, void*);
int sqlite3pager_pagecount(Pager*);
int sqlite3pager_truncate(Pager*,Pgno);
int sqlite3pager_begin(void*, int exFlag);
int sqlite3pager_commit(Pager*);
int sqlite3pager_sync(Pager*,const char *zMaster, Pgno);
int sqlite3pager_rollback(Pager*);
int sqlite3pager_isreadonly(Pager*);
int sqlite3pager_stmt_begin(Pager*);
int sqlite3pager_stmt_commit(Pager*);
int sqlite3pager_stmt_rollback(Pager*);
void sqlite3pager_dont_rollback(void*);
void sqlite3pager_dont_write(Pager*, Pgno);
int *sqlite3pager_stats(Pager*);
void sqlite3pager_set_safety_level(Pager*,int);
const char *sqlite3pager_filename(Pager*);
const char *sqlite3pager_dirname(Pager*);
const char *sqlite3pager_journalname(Pager*);
int sqlite3pager_rename(Pager*, const char *zNewName);
void sqlite3pager_set_codec(Pager*,void(*)(void*,void*,Pgno,int),void*);
int sqlite3pager_movepage(Pager*,void*,Pgno);
int sqlite3pager_reset(Pager*);
#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
int sqlite3pager_lockstate(Pager*);
#endif
#ifdef SQLITE_TEST
void sqlite3pager_refdump(Pager*);
int pager3_refinfo_enable;
#endif |
