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Fix a problem with savepoint and incremental-vacuum. (CVS 6066)

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FossilOrigin-Name: 08352f9ea9d2a1759320efc46e418079000855cb
This commit is contained in:
danielk1977
2008-12-27 15:23:13 +00:00
parent 45783d0148
commit 3460d19c85
8 changed files with 306 additions and 138 deletions
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162
src/pager.c
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@@ -18,7 +18,7 @@
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.523 2008/12/23 19:15:57 danielk1977 Exp $
** @(#) $Id: pager.c,v 1.524 2008/12/27 15:23:13 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
@@ -172,6 +172,18 @@ struct PagerSavepoint {
** next successful rollback is performed on the pager cache. Also,
** SQLITE_FULL does not affect the sqlite3PagerGet() and sqlite3PagerLookup()
** APIs, they may still be used successfully.
**
** Managing the size of the database file in pages is a little complicated.
** The variable Pager.dbSize contains the number of pages that the database
** image currently contains. As the database image grows or shrinks this
** variable is updated. The variable Pager.dbFileSize contains the number
** of pages in the database file. This may be different from Pager.dbSize
** if some pages have been appended to the database image but not yet written
** out from the cache to the actual file on disk. Or if the image has been
** truncated by an incremental-vacuum operation. The Pager.dbOrigSize variable
** contains the number of pages in the database image when the current
** transaction was opened. The contents of all three of these variables is
** only guaranteed to be correct if the boolean Pager.dbSizeValid is true.
*/
struct Pager {
sqlite3_vfs *pVfs; /* OS functions to use for IO */
@@ -196,10 +208,11 @@ struct Pager {
u8 dbModified; /* True if there are any changes to the Db */
u8 changeCountDone; /* Set after incrementing the change-counter */
u8 dbSizeValid; /* Set when dbSize is correct */
Pgno dbSize; /* Number of pages in the database */
Pgno dbOrigSize; /* dbSize before the current transaction */
Pgno dbFileSize; /* Number of pages in the database file */
u32 vfsFlags; /* Flags for sqlite3_vfs.xOpen() */
int errCode; /* One of several kinds of errors */
Pgno dbSize; /* Number of pages in the file */
Pgno origDbSize; /* dbSize before the current change */
int nRec; /* Number of pages written to the journal */
u32 cksumInit; /* Quasi-random value added to every checksum */
int stmtNRec; /* Number of records in stmt subjournal */
@@ -322,28 +335,30 @@ static const unsigned char aJournalMagic[] = {
#define PAGER_MAX_PGNO 2147483647
/*
** Return false if it is necessary to write page *pPg into the sub-journal.
** More accurately, true is returned if either:
** Return true if it is necessary to write page *pPg into the sub-journal.
** A page needs to be written into the sub-journal if there exists one
** or more open savepoints for which:
**
** * No savepoints are open, or
** * The page has been saved to the sub-journal since the most recent
** savepoint was opened.
**
** TODO: There's a bug here. To do with PagerSavepoint.nOrig. Also consider
** the idea that the page may not be required by the outermost savepoint
** but may be required by some earlier savepoint, due to an incremental
** vacuum operation.
** * The page-number is less than or equal to PagerSavepoint.nOrig, and
** * The bit corresponding to the page-number is not set in
** PagerSavepoint.pInSavepoint.
*/
static int pageInSavepoint(PgHdr *pPg){
static int subjRequiresPage(PgHdr *pPg){
Pgno pgno = pPg->pgno;
Pager *pPager = pPg->pPager;
if( pPager->nSavepoint==0 ){
return 1;
int i;
for(i=0; i<pPager->nSavepoint; i++){
PagerSavepoint *p = &pPager->aSavepoint[i];
if( p->nOrig>=pgno && 0==sqlite3BitvecTest(p->pInSavepoint, pgno) ){
return 1;
}
}
return sqlite3BitvecTest(
pPager->aSavepoint[pPager->nSavepoint-1].pInSavepoint, pPg->pgno
);
return 0;
}
/*
** Return true if the page is already in the journal file.
*/
static int pageInJournal(PgHdr *pPg){
return sqlite3BitvecTest(pPg->pPager->pInJournal, pPg->pgno);
}
@@ -715,7 +730,7 @@ static int writeJournalHdr(Pager *pPager){
sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
/* The initial database size */
put32bits(&zHeader[sizeof(aJournalMagic)+8], pPager->dbSize);
put32bits(&zHeader[sizeof(aJournalMagic)+8], pPager->dbOrigSize);
/* The assumed sector size for this process */
put32bits(&zHeader[sizeof(aJournalMagic)+12], pPager->sectorSize);
@@ -996,7 +1011,7 @@ static void pager_unlock(Pager *pPager){
releaseAllSavepoint(pPager);
pPager->journalOff = 0;
pPager->journalStarted = 0;
pPager->origDbSize = 0;
pPager->dbOrigSize = 0;
}
pPager->state = PAGER_UNLOCK;
@@ -1089,7 +1104,7 @@ static int pager_end_transaction(Pager *pPager, int hasMaster){
}else if( pPager->state==PAGER_SYNCED ){
pPager->state = PAGER_EXCLUSIVE;
}
pPager->origDbSize = 0;
pPager->dbOrigSize = 0;
pPager->setMaster = 0;
pPager->needSync = 0;
/* lruListSetFirstSynced(pPager); */
@@ -1232,6 +1247,9 @@ static int pager_playback_one_page(
){
i64 ofst = (pgno-1)*(i64)pPager->pageSize;
rc = sqlite3OsWrite(pPager->fd, aData, pPager->pageSize, ofst);
if( pgno>pPager->dbFileSize ){
pPager->dbFileSize = pgno;
}
}
if( pPg ){
/* No page should ever be explicitly rolled back that is in use, except
@@ -1417,6 +1435,9 @@ static int pager_truncate(Pager *pPager, Pgno nPage){
}else{
rc = sqlite3OsWrite(pPager->fd, "", 1, newSize-1);
}
if( rc==SQLITE_OK ){
pPager->dbFileSize = nPage;
}
}
}
if( rc==SQLITE_OK ){
@@ -1654,7 +1675,7 @@ static int pagerPlaybackSavepoint(Pager *pPager, PagerSavepoint *pSavepoint){
/* Truncate the database back to the size it was before the
** savepoint being reverted was opened.
*/
rc = pager_truncate(pPager, pSavepoint?pSavepoint->nOrig:pPager->origDbSize);
rc = pager_truncate(pPager, pSavepoint?pSavepoint->nOrig:pPager->dbOrigSize);
assert( pPager->state>=PAGER_SHARED );
/* Now roll back all main journal file records that occur after byte
@@ -2177,7 +2198,8 @@ int sqlite3PagerPagecount(Pager *pPager, int *pnPage){
n /= pPager->pageSize;
}
if( pPager->state!=PAGER_UNLOCK ){
pPager->dbSize = (int)n;
pPager->dbSize = (Pgno)n;
pPager->dbFileSize = (Pgno)n;
pPager->dbSizeValid = 1;
}
}
@@ -2248,7 +2270,11 @@ static int pager_wait_on_lock(Pager *pPager, int locktype){
}
/*
** Truncate the file to the number of pages specified.
** Truncate the file to the number of pages specified.
**
** Unless an IO error occurs, this function is guaranteed to modify the
** database file itself. If an exclusive lock is not held when this function
** is called, one is obtained before truncating the file.
*/
int sqlite3PagerTruncate(Pager *pPager, Pgno nPage){
int rc = SQLITE_OK;
@@ -2257,7 +2283,7 @@ int sqlite3PagerTruncate(Pager *pPager, Pgno nPage){
sqlite3PagerPagecount(pPager, 0);
if( pPager->errCode ){
rc = pPager->errCode;
}else if( nPage<pPager->dbSize ){
}else if( nPage<pPager->dbFileSize ){
rc = syncJournal(pPager);
if( rc==SQLITE_OK ){
/* Get an exclusive lock on the database before truncating. */
@@ -2271,6 +2297,36 @@ int sqlite3PagerTruncate(Pager *pPager, Pgno nPage){
return rc;
}
#ifndef SQLITE_OMIT_AUTOVACUUM
/*
** Truncate the in-memory database file image to nPage pages. Unlike
** sqlite3PagerTruncate(), this function does not actually modify the
** database file on disk. It just sets the internal state of the pager
** object so that the truncation will be done when the current
** transaction is committed.
*/
void sqlite3PagerTruncateImage(Pager *pPager, Pgno nPage){
assert( pPager->dbSizeValid );
assert( pPager->dbSize>=nPage );
pPager->dbSize = nPage;
}
/*
** Return the current size of the database file image in pages. This
** function differs from sqlite3PagerPagecount() in two ways:
**
** a) It may only be called when at least one reference to a database
** page is held. This guarantees that the database size is already
** known and a call to sqlite3OsFileSize() is not required.
**
** b) The return value is not adjusted for the locking page.
*/
Pgno sqlite3PagerImageSize(Pager *pPager){
assert( pPager->dbSizeValid );
return pPager->dbSize;
}
#endif /* ifndef SQLITE_OMIT_AUTOVACUUM */
/*
** Shutdown the page cache. Free all memory and close all files.
**
@@ -2480,6 +2536,9 @@ static int pager_write_pagelist(PgHdr *pList){
if( pList->pgno==1 ){
memcpy(&pPager->dbFileVers, &pData[24], sizeof(pPager->dbFileVers));
}
if( pList->pgno>pPager->dbFileSize ){
pPager->dbFileSize = pList->pgno;
}
}
#ifndef NDEBUG
else{
@@ -3076,7 +3135,7 @@ static int pager_open_journal(Pager *pPager){
rc = pPager->errCode;
goto failed_to_open_journal;
}
pPager->origDbSize = pPager->dbSize;
pPager->dbOrigSize = pPager->dbSize;
rc = writeJournalHdr(pPager);
@@ -3156,14 +3215,14 @@ int sqlite3PagerBegin(DbPage *pPg, int exFlag){
** overwritten with zeros.
*/
assert( pPager->nRec==0 );
assert( pPager->origDbSize==0 );
assert( pPager->dbOrigSize==0 );
assert( pPager->pInJournal==0 );
sqlite3PagerPagecount(pPager, 0);
pPager->pInJournal = sqlite3BitvecCreate( pPager->dbSize );
if( !pPager->pInJournal ){
rc = SQLITE_NOMEM;
}else{
pPager->origDbSize = pPager->dbSize;
pPager->dbOrigSize = pPager->dbSize;
rc = writeJournalHdr(pPager);
}
}
@@ -3223,7 +3282,7 @@ static int pager_write(PgHdr *pPg){
** to the journal then we can return right away.
*/
sqlite3PcacheMakeDirty(pPg);
if( pageInJournal(pPg) && pageInSavepoint(pPg) ){
if( pageInJournal(pPg) && !subjRequiresPage(pPg) ){
pPager->dirtyCache = 1;
pPager->dbModified = 1;
}else{
@@ -3254,7 +3313,7 @@ static int pager_write(PgHdr *pPg){
** the transaction journal if it is not there already.
*/
if( !pageInJournal(pPg) && pPager->journalOpen ){
if( pPg->pgno<=pPager->origDbSize ){
if( pPg->pgno<=pPager->dbOrigSize ){
u32 cksum;
char *pData2;
@@ -3320,10 +3379,10 @@ static int pager_write(PgHdr *pPg){
** the statement journal format differs from the standard journal format
** in that it omits the checksums and the header.
*/
if( !pageInSavepoint(pPg) ){
if( subjRequiresPage(pPg) ){
i64 offset = pPager->stmtNRec*(4+pPager->pageSize);
char *pData2 = CODEC2(pPager, pData, pPg->pgno, 7);
assert( pageInJournal(pPg) || pPg->pgno>pPager->origDbSize );
assert( pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
rc = write32bits(pPager->sjfd, offset, pPg->pgno);
if( rc==SQLITE_OK ){
rc = sqlite3OsWrite(pPager->sjfd, pData2, pPager->pageSize, offset+4);
@@ -3488,12 +3547,12 @@ int sqlite3PagerDontWrite(DbPage *pDbPage){
Pager *pPager = pPg->pPager;
int rc;
if( pPg->pgno>pPager->origDbSize ){
if( pPg->pgno>pPager->dbOrigSize ){
return SQLITE_OK;
}
if( pPager->pAlwaysRollback==0 ){
assert( pPager->pInJournal );
pPager->pAlwaysRollback = sqlite3BitvecCreate(pPager->origDbSize);
pPager->pAlwaysRollback = sqlite3BitvecCreate(pPager->dbOrigSize);
if( !pPager->pAlwaysRollback ){
return SQLITE_NOMEM;
}
@@ -3502,7 +3561,7 @@ int sqlite3PagerDontWrite(DbPage *pDbPage){
if( rc==SQLITE_OK && (pPg->flags&PGHDR_DIRTY) && pPager->nSavepoint==0 ){
assert( pPager->state>=PAGER_SHARED );
if( pPager->dbSize==pPg->pgno && pPager->origDbSize<pPager->dbSize ){
if( pPager->dbSize==pPg->pgno && pPager->dbOrigSize<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.
** When the database file grows, we must make sure that the last page
@@ -3545,14 +3604,14 @@ void sqlite3PagerDontRollback(DbPage *pPg){
*/
if( pPager->journalOpen==0
|| sqlite3BitvecTest(pPager->pAlwaysRollback, pPg->pgno)
|| pPg->pgno>pPager->origDbSize
|| pPg->pgno>pPager->dbOrigSize
){
return;
}
#ifdef SQLITE_SECURE_DELETE
if( sqlite3BitvecTest(pPager->pInJournal, pPg->pgno)!=0
|| pPg->pgno>pPager->origDbSize ){
|| pPg->pgno>pPager->dbOrigSize ){
return;
}
#endif
@@ -3567,7 +3626,7 @@ void sqlite3PagerDontRollback(DbPage *pPg){
** pages on the freelist (ex: corrupt9.test) then the following is not
** necessarily true:
*/
/* assert( !pPg->inJournal && (int)pPg->pgno <= pPager->origDbSize ); */
/* assert( !pPg->inJournal && (int)pPg->pgno <= pPager->dbOrigSize ); */
assert( pPager->pInJournal!=0 );
sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
@@ -3611,6 +3670,7 @@ static int pager_incr_changecounter(Pager *pPager, int isDirect){
#ifdef SQLITE_ENABLE_ATOMIC_WRITE
if( isDirect && pPager->fd->pMethods ){
const void *zBuf = pPgHdr->pData;
assert( pPager->dbFileSize>0 );
rc = sqlite3OsWrite(pPager->fd, zBuf, pPager->pageSize, 0);
}
#endif
@@ -3678,8 +3738,8 @@ int sqlite3PagerCommitPhaseOne(
return SQLITE_OK;
}
PAGERTRACE4("DATABASE SYNC: File=%s zMaster=%s nTrunc=%d\n",
pPager->zFilename, zMaster, nTrunc);
PAGERTRACE4("DATABASE SYNC: File=%s zMaster=%s nSize=%d\n",
pPager->zFilename, zMaster, pPager->dbSize);
/* If this is an in-memory db, or no pages have been written to, or this
** function has already been called, it is a no-op.
@@ -3705,7 +3765,7 @@ int sqlite3PagerCommitPhaseOne(
!zMaster &&
pPager->journalOpen &&
pPager->journalOff==jrnlBufferSize(pPager) &&
nTrunc==0 &&
pPager->dbSize>=pPager->dbFileSize &&
(pPg==0 || pPg->pDirty==0)
);
assert( pPager->journalOpen || pPager->journalMode==PAGER_JOURNALMODE_OFF );
@@ -3742,14 +3802,15 @@ int sqlite3PagerCommitPhaseOne(
if( rc!=SQLITE_OK ) goto sync_exit;
if( pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
#ifndef SQLITE_OMIT_AUTOVACUUM
if( nTrunc!=0 ){
if( pPager->dbSize<pPager->dbOrigSize ){
/* If this transaction has made the database smaller, then all pages
** being discarded by the truncation must be written to the journal
** file.
*/
Pgno i;
Pgno iSkip = PAGER_MJ_PGNO(pPager);
for( i=nTrunc+1; i<=pPager->origDbSize; i++ ){
Pgno dbSize = pPager->dbSize;
for( i=pPager->dbSize+1; i<=pPager->dbOrigSize; i++ ){
if( !sqlite3BitvecTest(pPager->pInJournal, i) && i!=iSkip ){
rc = sqlite3PagerGet(pPager, i, &pPg);
if( rc!=SQLITE_OK ) goto sync_exit;
@@ -3758,6 +3819,7 @@ int sqlite3PagerCommitPhaseOne(
if( rc!=SQLITE_OK ) goto sync_exit;
}
}
pPager->dbSize = dbSize;
}
#endif
rc = writeMasterJournal(pPager, zMaster);
@@ -3768,8 +3830,8 @@ int sqlite3PagerCommitPhaseOne(
if( rc!=SQLITE_OK ) goto sync_exit;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( nTrunc!=0 ){
rc = sqlite3PagerTruncate(pPager, nTrunc);
if( pPager->dbSize<pPager->dbFileSize ){
rc = sqlite3PagerTruncate(pPager, pPager->dbSize);
if( rc!=SQLITE_OK ) goto sync_exit;
}
#endif
@@ -3797,8 +3859,8 @@ int sqlite3PagerCommitPhaseOne(
IOTRACE(("DBSYNC %p\n", pPager))
pPager->state = PAGER_SYNCED;
}else if( MEMDB && nTrunc!=0 ){
rc = sqlite3PagerTruncate(pPager, nTrunc);
}else if( MEMDB && pPager->dbSize<pPager->dbFileSize ){
rc = sqlite3PagerTruncate(pPager, pPager->dbSize);
}
sync_exit:
@@ -4133,7 +4195,7 @@ int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
*/
if( (pPg->flags&PGHDR_NEED_SYNC) && !isCommit ){
needSyncPgno = pPg->pgno;
assert( pageInJournal(pPg) || pPg->pgno>pPager->origDbSize );
assert( pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
assert( pPg->flags&PGHDR_DIRTY );
assert( pPager->needSync );
}
@@ -4182,7 +4244,7 @@ int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
assert( pPager->needSync );
rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
if( rc!=SQLITE_OK ){
if( pPager->pInJournal && needSyncPgno<=pPager->origDbSize ){
if( pPager->pInJournal && needSyncPgno<=pPager->dbOrigSize ){
sqlite3BitvecClear(pPager->pInJournal, needSyncPgno);
}
return rc;