1
0
mirror of https://github.com/sqlite/sqlite.git synced 2025-08-07 02:42:48 +03:00

Make sure that the database size cache in the pager is invalidated whenever

the database is unlocked.  A stale value in the database size cache can
result in database corruption on a heavily loaded system running
autovacuum. (CVS 3548)

FossilOrigin-Name: 6806b9ecb5e3b90e793c5862404e76485df33b25
This commit is contained in:
drh
2007-01-03 15:34:29 +00:00
parent 588f5bc31b
commit 1aa2d8b55b
3 changed files with 41 additions and 23 deletions

View File

@@ -18,7 +18,7 @@
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.278 2007/01/02 18:41:55 drh Exp $
** @(#) $Id: pager.c,v 1.279 2007/01/03 15:34:30 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
@@ -850,6 +850,22 @@ static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){
return p;
}
/*
** Unlock the database file.
**
** Once all locks have been removed from the database file, other
** processes or threads might change the file. So make sure all of
** our internal cache is invalidated.
*/
static void pager_unlock(Pager *pPager){
if( !MEMDB ){
sqlite3OsUnlock(pPager->fd, NO_LOCK);
pPager->dbSize = -1;
}
pPager->state = PAGER_UNLOCK;
}
/*
** Unlock the database and clear the in-memory cache. This routine
** sets the state of the pager back to what it was when it was first
@@ -874,9 +890,7 @@ static void pager_reset(Pager *pPager){
if( pPager->state>=PAGER_RESERVED ){
sqlite3pager_rollback(pPager);
}
sqlite3OsUnlock(pPager->fd, NO_LOCK);
pPager->state = PAGER_UNLOCK;
pPager->dbSize = -1;
pager_unlock(pPager);
pPager->nRef = 0;
assert( pPager->journalOpen==0 );
}
@@ -1425,6 +1439,7 @@ static int pager_stmt_playback(Pager *pPager){
if( pPager->state>=PAGER_EXCLUSIVE ){
rc = pager_truncate(pPager, pPager->stmtSize);
}
assert( pPager->state>=PAGER_SHARED );
pPager->dbSize = pPager->stmtSize;
/* Figure out how many records are in the statement journal.
@@ -1974,9 +1989,15 @@ static void memoryTruncate(Pager *pPager){
*/
static int pager_wait_on_lock(Pager *pPager, int locktype){
int rc;
/* The OS lock values must be the same as the Pager lock values */
assert( PAGER_SHARED==SHARED_LOCK );
assert( PAGER_RESERVED==RESERVED_LOCK );
assert( PAGER_EXCLUSIVE==EXCLUSIVE_LOCK );
/* If the file is currently unlocked then the size must be unknown */
assert( pPager->state>=PAGER_SHARED || pPager->dbSize<0 || MEMDB );
if( pPager->state>=locktype ){
rc = SQLITE_OK;
}else{
@@ -1995,6 +2016,7 @@ static int pager_wait_on_lock(Pager *pPager, int locktype){
*/
int sqlite3pager_truncate(Pager *pPager, Pgno nPage){
int rc;
assert( pPager->state>=PAGER_SHARED || MEMDB );
sqlite3pager_pagecount(pPager);
if( pPager->errCode ){
rc = pPager->errCode;
@@ -2064,16 +2086,12 @@ int sqlite3pager_close(Pager *pPager){
disable_simulated_io_errors();
sqlite3pager_rollback(pPager);
enable_simulated_io_errors();
if( !MEMDB ){
sqlite3OsUnlock(pPager->fd, NO_LOCK);
}
pager_unlock(pPager);
assert( pPager->errCode || pPager->journalOpen==0 );
break;
}
case PAGER_SHARED: {
if( !MEMDB ){
sqlite3OsUnlock(pPager->fd, NO_LOCK);
}
pager_unlock(pPager);
break;
}
default: {
@@ -2674,8 +2692,7 @@ int sqlite3pager_get(Pager *pPager, Pgno pgno, void **ppPage){
*/
rc = sqlite3OsLock(pPager->fd, EXCLUSIVE_LOCK);
if( rc!=SQLITE_OK ){
sqlite3OsUnlock(pPager->fd, NO_LOCK);
pPager->state = PAGER_UNLOCK;
pager_unlock(pPager);
return pager_error(pPager, rc);
}
pPager->state = PAGER_EXCLUSIVE;
@@ -2690,8 +2707,7 @@ int sqlite3pager_get(Pager *pPager, Pgno pgno, void **ppPage){
*/
rc = sqlite3OsOpenReadOnly(pPager->zJournal, &pPager->jfd);
if( rc!=SQLITE_OK ){
sqlite3OsUnlock(pPager->fd, NO_LOCK);
pPager->state = PAGER_UNLOCK;
pager_unlock(pPager);
return SQLITE_BUSY;
}
pPager->journalOpen = 1;
@@ -2973,8 +2989,7 @@ failed_to_open_journal:
*/
sqlite3OsDelete(pPager->zJournal);
}else{
sqlite3OsUnlock(pPager->fd, NO_LOCK);
pPager->state = PAGER_UNLOCK;
pager_unlock(pPager);
}
return rc;
}
@@ -3233,6 +3248,7 @@ int sqlite3pager_write(void *pData){
/* Update the database size and return.
*/
assert( pPager->state>=PAGER_SHARED );
if( pPager->dbSize<(int)pPg->pgno ){
pPager->dbSize = pPg->pgno;
if( !MEMDB && pPager->dbSize==PENDING_BYTE/pPager->pageSize ){
@@ -3308,6 +3324,7 @@ void sqlite3pager_dont_write(Pager *pPager, Pgno pgno){
assert( pPg!=0 ); /* We never call _dont_write unless the page is in mem */
pPg->alwaysRollback = 1;
if( pPg->dirty && !pPager->stmtInUse ){
assert( pPager->state>=PAGER_SHARED );
if( pPager->dbSize==(int)pPg->pgno && pPager->origDbSize<pPager->dbSize ){
/* If this pages is the last page in the file and the file has grown
** during the current transaction, then do NOT mark the page as clean.
@@ -3544,6 +3561,7 @@ int sqlite3pager_stmt_begin(Pager *pPager){
int rc;
char zTemp[SQLITE_TEMPNAME_SIZE];
assert( !pPager->stmtInUse );
assert( pPager->state>=PAGER_SHARED );
assert( pPager->dbSize>=0 );
TRACE2("STMT-BEGIN %d\n", PAGERID(pPager));
if( MEMDB ){