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Overview
Comment:Auto-vacuum: Ensure pages to be removed by database truncation are in the journal file. Also fix an sqlite3pager_movepage() bug. (CVS 2074)
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SHA1: 081676e491760a45325e2349b177d6382faab9f5
User & Date: danielk1977 2004-11-06 12:26:08.000
Context
2004-11-07
13:01
Reindex tests added and bugs fixed. (CVS 2075) (check-in: ad433ec2b6 user: drh tags: trunk)
2004-11-06
12:26
Auto-vacuum: Ensure pages to be removed by database truncation are in the journal file. Also fix an sqlite3pager_movepage() bug. (CVS 2074) (check-in: 081676e491 user: danielk1977 tags: trunk)
00:02
Compile and pass the quick regression tests with autovacuum disabled. (CVS 2073) (check-in: 89b9026a53 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/btree.c.
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/*
** 2004 April 6
**
** 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.
**
*************************************************************************
** $Id: btree.c,v 1.212 2004/11/06 00:02:48 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.











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/*
** 2004 April 6
**
** 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.
**
*************************************************************************
** $Id: btree.c,v 1.213 2004/11/06 12:26:08 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.
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  int nCell;
  u8 *data;
  BtCursor cur;
  Btree *pBt;
  int maxLocal, usableSize;
  char zContext[100];
  char *hit;



  /* Check that the page exists
  */
  cur.pBt = pBt = pCheck->pBt;
  usableSize = pBt->usableSize;
  if( iPage==0 ) return 0;
  if( checkRef(pCheck, iPage, zParentContext) ) return 0;







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  int nCell;
  u8 *data;
  BtCursor cur;
  Btree *pBt;
  int maxLocal, usableSize;
  char zContext[100];
  char *hit;

  sprintf(zContext, "Page %d: ", iPage);

  /* Check that the page exists
  */
  cur.pBt = pBt = pCheck->pBt;
  usableSize = pBt->usableSize;
  if( iPage==0 ) return 0;
  if( checkRef(pCheck, iPage, zParentContext) ) return 0;
Changes to src/os_test.c.
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        rc = sqlite3RealSeek(&pFile->fd, BLOCK_OFFSET(i));
      }
      if( rc==SQLITE_OK && !skip ){
        int len = BLOCKSIZE;
        if( BLOCK_OFFSET(i+1)>nMax ){
          len = nMax-BLOCK_OFFSET(i);
        }

        if( trash ){
          sqlite3Randomness(len, p);
        }
        rc = sqlite3RealWrite(&pFile->fd, p, len);

      }
      sqliteFree(p);
    }
  }
  sqliteFree(pFile->apBlk);
  pFile->nBlk = 0;
  pFile->apBlk = 0;







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        rc = sqlite3RealSeek(&pFile->fd, BLOCK_OFFSET(i));
      }
      if( rc==SQLITE_OK && !skip ){
        int len = BLOCKSIZE;
        if( BLOCK_OFFSET(i+1)>nMax ){
          len = nMax-BLOCK_OFFSET(i);
        }
        if( len>0 ){
          if( trash ){
            sqlite3Randomness(len, p);
          }
          rc = sqlite3RealWrite(&pFile->fd, p, len);
        }
      }
      sqliteFree(p);
    }
  }
  sqliteFree(pFile->apBlk);
  pFile->nBlk = 0;
  pFile->apBlk = 0;
Changes to src/pager.c.
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** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.173 2004/11/05 16:37:03 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>








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** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.174 2004/11/06 12:26:08 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

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#else
#define TRACE1(X)
#define TRACE2(X,Y)
#define TRACE3(X,Y,Z)
#define TRACE4(X,Y,Z,W)
#endif









/*
** The page cache as a whole is always in one of the following
** states:
**
**   PAGER_UNLOCK        The page cache is not currently reading or 
**                       writing the database file.  There is no







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#else
#define TRACE1(X)
#define TRACE2(X,Y)
#define TRACE3(X,Y,Z)
#define TRACE4(X,Y,Z,W)
#endif

#ifdef OS_TEST
#define PAGERID(p) (p->fd->fd.h)
#define FILEHANDLEID(fd) (fd->fd.h)
#else
#define PAGERID(p) (p->fd.h)
#define FILEHANDLEID(fd) (fd.h)
#endif

/*
** The page cache as a whole is always in one of the following
** states:
**
**   PAGER_UNLOCK        The page cache is not currently reading or 
**                       writing the database file.  There is no
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  ** not the database file. The page is left marked dirty in this case.
  **
  ** If in EXCLUSIVE state, then we update the pager cache if it exists
  ** and the main file. The page is then marked not dirty.
  */
  pPg = pager_lookup(pPager, pgno);
  assert( pPager->state>=PAGER_EXCLUSIVE || pPg );
  TRACE3("PLAYBACK %d page %d\n", pPager->fd.h, pgno);
  if( pPager->state>=PAGER_EXCLUSIVE ){
    sqlite3OsSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
    rc = sqlite3OsWrite(&pPager->fd, aData, pPager->pageSize);
  }
  if( pPg ){
    /* No page should ever be rolled back that is in use, except for page
    ** 1 which is held in use in order to keep the lock on the database







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  ** not the database file. The page is left marked dirty in this case.
  **
  ** If in EXCLUSIVE state, then we update the pager cache if it exists
  ** and the main file. The page is then marked not dirty.
  */
  pPg = pager_lookup(pPager, pgno);
  assert( pPager->state>=PAGER_EXCLUSIVE || pPg );
  TRACE3("PLAYBACK %d page %d\n", PAGERID(pPager), pgno);
  if( pPager->state>=PAGER_EXCLUSIVE ){
    sqlite3OsSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
    rc = sqlite3OsWrite(&pPager->fd, aData, pPager->pageSize);
  }
  if( pPg ){
    /* No page should ever be rolled back that is in use, except for page
    ** 1 which is held in use in order to keep the lock on the database
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  int rc = SQLITE_OK;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    char zBuf[SQLITE_MAX_PAGE_SIZE];
    if( !pPg->dirty ) continue;
    if( (int)pPg->pgno <= pPager->origDbSize ){
      sqlite3OsSeek(&pPager->fd, pPager->pageSize*(i64)(pPg->pgno-1));
      rc = sqlite3OsRead(&pPager->fd, zBuf, pPager->pageSize);
      TRACE3("REFETCH %d page %d\n", pPager->fd.h, pPg->pgno);
      if( rc ) break;
      CODEC(pPager, zBuf, pPg->pgno, 2);
    }else{
      memset(zBuf, 0, pPager->pageSize);
    }
    if( pPg->nRef==0 || memcmp(zBuf, PGHDR_TO_DATA(pPg), pPager->pageSize) ){
      memcpy(PGHDR_TO_DATA(pPg), zBuf, pPager->pageSize);







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  int rc = SQLITE_OK;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    char zBuf[SQLITE_MAX_PAGE_SIZE];
    if( !pPg->dirty ) continue;
    if( (int)pPg->pgno <= pPager->origDbSize ){
      sqlite3OsSeek(&pPager->fd, pPager->pageSize*(i64)(pPg->pgno-1));
      rc = sqlite3OsRead(&pPager->fd, zBuf, pPager->pageSize);
      TRACE3("REFETCH %d page %d\n", PAGERID(pPager), pPg->pgno);
      if( rc ) break;
      CODEC(pPager, zBuf, pPg->pgno, 2);
    }else{
      memset(zBuf, 0, pPager->pageSize);
    }
    if( pPg->nRef==0 || memcmp(zBuf, PGHDR_TO_DATA(pPg), pPager->pageSize) ){
      memcpy(PGHDR_TO_DATA(pPg), zBuf, pPager->pageSize);
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  nameLen = strlen(zFullPathname);
  pPager = sqliteMalloc( sizeof(*pPager) + nameLen*3 + 30 );
  if( pPager==0 ){
    sqlite3OsClose(&fd);
    sqliteFree(zFullPathname);
    return SQLITE_NOMEM;
  }
  TRACE3("OPEN %d %s\n", fd.h, zFullPathname);
  pPager->zFilename = (char*)&pPager[1];
  pPager->zDirectory = &pPager->zFilename[nameLen+1];
  pPager->zJournal = &pPager->zDirectory[nameLen+1];
  strcpy(pPager->zFilename, zFullPathname);
  strcpy(pPager->zDirectory, zFullPathname);
  for(i=nameLen; i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;







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  nameLen = strlen(zFullPathname);
  pPager = sqliteMalloc( sizeof(*pPager) + nameLen*3 + 30 );
  if( pPager==0 ){
    sqlite3OsClose(&fd);
    sqliteFree(zFullPathname);
    return SQLITE_NOMEM;
  }
  TRACE3("OPEN %d %s\n", FILEHANDLEID(fd), zFullPathname);
  pPager->zFilename = (char*)&pPager[1];
  pPager->zDirectory = &pPager->zFilename[nameLen+1];
  pPager->zJournal = &pPager->zDirectory[nameLen+1];
  strcpy(pPager->zFilename, zFullPathname);
  strcpy(pPager->zDirectory, zFullPathname);
  for(i=nameLen; i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;
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    assert( pPager->pLast==pPg );
    pPager->pLast = pPg->pPrevFree;
  }
  pPg->pNextFree = pPg->pPrevFree = 0;

  /* Unlink from the pgno hash table */
  unlinkHashChain(pPager, pPg);
/*
  if( pPg->pNextHash ){
    pPg->pNextHash->pPrevHash = pPg->pPrevHash;
  }
  if( pPg->pPrevHash ){
    pPg->pPrevHash->pNextHash = pPg->pNextHash;
  }else{
    int h = pager_hash(pPg->pgno);
    assert( pPager->aHash[h]==pPg );
    pPager->aHash[h] = pPg->pNextHash;
  }
  pPg->pNextHash = pPg->pPrevHash = 0;
*/
}

/*
** This routine is used to truncate an in-memory database.  Delete
** all pages whose pgno is larger than pPager->dbSize and is unreferenced.
** Referenced pages larger than pPager->dbSize are zeroed.
*/







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    assert( pPager->pLast==pPg );
    pPager->pLast = pPg->pPrevFree;
  }
  pPg->pNextFree = pPg->pPrevFree = 0;

  /* Unlink from the pgno hash table */
  unlinkHashChain(pPager, pPg);













}

/*
** This routine is used to truncate an in-memory database.  Delete
** all pages whose pgno is larger than pPager->dbSize and is unreferenced.
** Referenced pages larger than pPager->dbSize are zeroed.
*/
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      assert( !pHist->pOrig );
      assert( !pHist->pStmt );
    }
#endif
    pNext = pPg->pNextAll;
    sqliteFree(pPg);
  }
  TRACE2("CLOSE %d\n", pPager->fd.h);
  sqlite3OsClose(&pPager->fd);
  assert( pPager->journalOpen==0 );
  /* Temp files are automatically deleted by the OS
  ** if( pPager->tempFile ){
  **   sqlite3OsDelete(pPager->zFilename);
  ** }
  */







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      assert( !pHist->pOrig );
      assert( !pHist->pStmt );
    }
#endif
    pNext = pPg->pNextAll;
    sqliteFree(pPg);
  }
  TRACE2("CLOSE %d\n", PAGERID(pPager));
  sqlite3OsClose(&pPager->fd);
  assert( pPager->journalOpen==0 );
  /* Temp files are automatically deleted by the OS
  ** if( pPager->tempFile ){
  **   sqlite3OsDelete(pPager->zFilename);
  ** }
  */
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      {
        /* Write the nRec value into the journal file header. If in
        ** full-synchronous mode, sync the journal first. This ensures that
        ** all data has really hit the disk before nRec is updated to mark
        ** it as a candidate for rollback. 
        */
        if( pPager->fullSync ){
          TRACE2("SYNC journal of %d\n", pPager->fd.h);
          rc = sqlite3OsSync(&pPager->jfd);
          if( rc!=0 ) return rc;
        }
        sqlite3OsSeek(&pPager->jfd, pPager->journalHdr + sizeof(aJournalMagic));
        rc = write32bits(&pPager->jfd, pPager->nRec);
        if( rc ) return rc;

        sqlite3OsSeek(&pPager->jfd, pPager->journalOff);
      }
      TRACE2("SYNC journal of %d\n", pPager->fd.h);
      rc = sqlite3OsSync(&pPager->jfd);
      if( rc!=0 ) return rc;
      pPager->journalStarted = 1;
    }
    pPager->needSync = 0;

    /* Erase the needSync flag from every page.







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      {
        /* Write the nRec value into the journal file header. If in
        ** full-synchronous mode, sync the journal first. This ensures that
        ** all data has really hit the disk before nRec is updated to mark
        ** it as a candidate for rollback. 
        */
        if( pPager->fullSync ){
          TRACE2("SYNC journal of %d\n", PAGERID(pPager));
          rc = sqlite3OsSync(&pPager->jfd);
          if( rc!=0 ) return rc;
        }
        sqlite3OsSeek(&pPager->jfd, pPager->journalHdr + sizeof(aJournalMagic));
        rc = write32bits(&pPager->jfd, pPager->nRec);
        if( rc ) return rc;

        sqlite3OsSeek(&pPager->jfd, pPager->journalOff);
      }
      TRACE2("SYNC journal of %d\n", PAGERID(pPager));
      rc = sqlite3OsSync(&pPager->jfd);
      if( rc!=0 ) return rc;
      pPager->journalStarted = 1;
    }
    pPager->needSync = 0;

    /* Erase the needSync flag from every page.
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    /* If there are dirty pages in the page cache with page numbers greater
    ** than Pager.dbSize, this means sqlite3pager_truncate() was called to
    ** make the file smaller (presumably by auto-vacuum code). Do not write
    ** any such pages to the file.
    */
    if( pList->pgno<=pPager->dbSize ){
      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 6);
      TRACE3("STORE %d page %d\n", pPager->fd.h, pList->pgno);
      rc = sqlite3OsWrite(&pPager->fd, PGHDR_TO_DATA(pList), pPager->pageSize);
      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 0);
    }
#ifndef NDEBUG
    else{
      TRACE3("NOSTORE %d page %d\n", pPager->fd.h, pList->pgno);
    }
#endif
    if( rc ) return rc;
    pList->dirty = 0;
    pList = pList->pDirty;
  }
  return SQLITE_OK;







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    /* If there are dirty pages in the page cache with page numbers greater
    ** than Pager.dbSize, this means sqlite3pager_truncate() was called to
    ** make the file smaller (presumably by auto-vacuum code). Do not write
    ** any such pages to the file.
    */
    if( pList->pgno<=pPager->dbSize ){
      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 6);
      TRACE3("STORE %d page %d\n", PAGERID(pPager), pList->pgno);
      rc = sqlite3OsWrite(&pPager->fd, PGHDR_TO_DATA(pList), pPager->pageSize);
      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 0);
    }
#ifndef NDEBUG
    else{
      TRACE3("NOSTORE %d page %d\n", PAGERID(pPager), pList->pgno);
    }
#endif
    if( rc ) return rc;
    pList->dirty = 0;
    pList = pList->pDirty;
  }
  return SQLITE_OK;
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    if( pPager->dbSize<(int)pgno ){
      memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
    }else{
      int rc;
      assert( MEMDB==0 );
      sqlite3OsSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
      rc = sqlite3OsRead(&pPager->fd, PGHDR_TO_DATA(pPg), pPager->pageSize);
      TRACE3("FETCH %d page %d\n", pPager->fd.h, pPg->pgno);
      CODEC(pPager, PGHDR_TO_DATA(pPg), pPg->pgno, 3);
      if( rc!=SQLITE_OK ){
        i64 fileSize;
        if( sqlite3OsFileSize(&pPager->fd,&fileSize)!=SQLITE_OK
               || fileSize>=pgno*pPager->pageSize ){
          sqlite3pager_unref(PGHDR_TO_DATA(pPg));
          return rc;







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    if( pPager->dbSize<(int)pgno ){
      memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
    }else{
      int rc;
      assert( MEMDB==0 );
      sqlite3OsSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
      rc = sqlite3OsRead(&pPager->fd, PGHDR_TO_DATA(pPg), pPager->pageSize);
      TRACE3("FETCH %d page %d\n", PAGERID(pPager), pPg->pgno);
      CODEC(pPager, PGHDR_TO_DATA(pPg), pPg->pgno, 3);
      if( rc!=SQLITE_OK ){
        i64 fileSize;
        if( sqlite3OsFileSize(&pPager->fd,&fileSize)!=SQLITE_OK
               || fileSize>=pgno*pPager->pageSize ){
          sqlite3pager_unref(PGHDR_TO_DATA(pPg));
          return rc;
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
          rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
        }
      }
      if( rc!=SQLITE_OK ){
        return rc;
      }
      pPager->dirtyCache = 0;
      TRACE2("TRANSACTION %d\n", pPager->fd.h);
      if( pPager->useJournal && !pPager->tempFile ){
        rc = pager_open_journal(pPager);
      }
    }
  }
  return rc;
}







|







2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
          rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
        }
      }
      if( rc!=SQLITE_OK ){
        return rc;
      }
      pPager->dirtyCache = 0;
      TRACE2("TRANSACTION %d\n", PAGERID(pPager));
      if( pPager->useJournal && !pPager->tempFile ){
        rc = pager_open_journal(pPager);
      }
    }
  }
  return rc;
}
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
    */
    if( !pPg->inJournal && (pPager->useJournal || MEMDB) ){
      if( (int)pPg->pgno <= pPager->origDbSize ){
        int szPg;
        u32 saved;
        if( MEMDB ){
          PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
          TRACE3("JOURNAL %d page %d\n", pPager->fd.h, pPg->pgno);
          assert( pHist->pOrig==0 );
          pHist->pOrig = sqliteMallocRaw( pPager->pageSize );
          if( pHist->pOrig ){
            memcpy(pHist->pOrig, PGHDR_TO_DATA(pPg), pPager->pageSize);
          }
        }else{
          u32 cksum;
          CODEC(pPager, pData, pPg->pgno, 7);
          cksum = pager_cksum(pPager, pPg->pgno, pData);
          saved = *(u32*)PGHDR_TO_EXTRA(pPg, pPager);
          store32bits(cksum, pPg, pPager->pageSize);
          szPg = pPager->pageSize+8;
          store32bits(pPg->pgno, pPg, -4);
          rc = sqlite3OsWrite(&pPager->jfd, &((char*)pData)[-4], szPg);
          pPager->journalOff += szPg;
          TRACE4("JOURNAL %d page %d needSync=%d\n",
                  pPager->fd.h, pPg->pgno, pPg->needSync);
          CODEC(pPager, pData, pPg->pgno, 0);
          *(u32*)PGHDR_TO_EXTRA(pPg, pPager) = saved;
          if( rc!=SQLITE_OK ){
            sqlite3pager_rollback(pPager);
            pPager->errMask |= PAGER_ERR_FULL;
            return rc;
          }
          pPager->nRec++;
          assert( pPager->aInJournal!=0 );
          pPager->aInJournal[pPg->pgno/8] |= 1<<(pPg->pgno&7);
          pPg->needSync = !pPager->noSync;
          if( pPager->stmtInUse ){
            pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
            page_add_to_stmt_list(pPg);
          }
        }
      }else{
        pPg->needSync = !pPager->journalStarted && !pPager->noSync;
        TRACE4("APPEND %d page %d needSync=%d\n",
                pPager->fd.h, pPg->pgno, pPg->needSync);
      }
      if( pPg->needSync ){
        pPager->needSync = 1;
      }
      pPg->inJournal = 1;
    }
  







|
















|



















|







2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
    */
    if( !pPg->inJournal && (pPager->useJournal || MEMDB) ){
      if( (int)pPg->pgno <= pPager->origDbSize ){
        int szPg;
        u32 saved;
        if( MEMDB ){
          PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
          TRACE3("JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
          assert( pHist->pOrig==0 );
          pHist->pOrig = sqliteMallocRaw( pPager->pageSize );
          if( pHist->pOrig ){
            memcpy(pHist->pOrig, PGHDR_TO_DATA(pPg), pPager->pageSize);
          }
        }else{
          u32 cksum;
          CODEC(pPager, pData, pPg->pgno, 7);
          cksum = pager_cksum(pPager, pPg->pgno, pData);
          saved = *(u32*)PGHDR_TO_EXTRA(pPg, pPager);
          store32bits(cksum, pPg, pPager->pageSize);
          szPg = pPager->pageSize+8;
          store32bits(pPg->pgno, pPg, -4);
          rc = sqlite3OsWrite(&pPager->jfd, &((char*)pData)[-4], szPg);
          pPager->journalOff += szPg;
          TRACE4("JOURNAL %d page %d needSync=%d\n",
                  PAGERID(pPager), pPg->pgno, pPg->needSync);
          CODEC(pPager, pData, pPg->pgno, 0);
          *(u32*)PGHDR_TO_EXTRA(pPg, pPager) = saved;
          if( rc!=SQLITE_OK ){
            sqlite3pager_rollback(pPager);
            pPager->errMask |= PAGER_ERR_FULL;
            return rc;
          }
          pPager->nRec++;
          assert( pPager->aInJournal!=0 );
          pPager->aInJournal[pPg->pgno/8] |= 1<<(pPg->pgno&7);
          pPg->needSync = !pPager->noSync;
          if( pPager->stmtInUse ){
            pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
            page_add_to_stmt_list(pPg);
          }
        }
      }else{
        pPg->needSync = !pPager->journalStarted && !pPager->noSync;
        TRACE4("APPEND %d page %d needSync=%d\n",
                PAGERID(pPager), pPg->pgno, pPg->needSync);
      }
      if( pPg->needSync ){
        pPager->needSync = 1;
      }
      pPg->inJournal = 1;
    }
  
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
      if( MEMDB ){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        assert( pHist->pStmt==0 );
        pHist->pStmt = sqliteMallocRaw( pPager->pageSize );
        if( pHist->pStmt ){
          memcpy(pHist->pStmt, PGHDR_TO_DATA(pPg), pPager->pageSize);
        }
        TRACE3("STMT-JOURNAL %d page %d\n", pPager->fd.h, pPg->pgno);
      }else{
        store32bits(pPg->pgno, pPg, -4);
        CODEC(pPager, pData, pPg->pgno, 7);
        rc = sqlite3OsWrite(&pPager->stfd,((char*)pData)-4, pPager->pageSize+4);
        TRACE3("STMT-JOURNAL %d page %d\n", pPager->fd.h, pPg->pgno);
        CODEC(pPager, pData, pPg->pgno, 0);
        if( rc!=SQLITE_OK ){
          sqlite3pager_rollback(pPager);
          pPager->errMask |= PAGER_ERR_FULL;
          return rc;
        }
        pPager->stmtNRec++;







|




|







2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
      if( MEMDB ){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        assert( pHist->pStmt==0 );
        pHist->pStmt = sqliteMallocRaw( pPager->pageSize );
        if( pHist->pStmt ){
          memcpy(pHist->pStmt, PGHDR_TO_DATA(pPg), pPager->pageSize);
        }
        TRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
      }else{
        store32bits(pPg->pgno, pPg, -4);
        CODEC(pPager, pData, pPg->pgno, 7);
        rc = sqlite3OsWrite(&pPager->stfd,((char*)pData)-4, pPager->pageSize+4);
        TRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
        CODEC(pPager, pData, pPg->pgno, 0);
        if( rc!=SQLITE_OK ){
          sqlite3pager_rollback(pPager);
          pPager->errMask |= PAGER_ERR_FULL;
          return rc;
        }
        pPager->stmtNRec++;
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
      ** When the database file grows, we must make sure that the last page
      ** gets written at least once so that the disk file will be the correct
      ** size. If you do not write this page and the size of the file
      ** on the disk ends up being too small, that can lead to database
      ** corruption during the next transaction.
      */
    }else{
      TRACE3("DONT_WRITE page %d of %d\n", pgno, pPager->fd.h);
      pPg->dirty = 0;
    }
  }
}

/*
** A call to this routine tells the pager that if a rollback occurs,







|







2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
      ** When the database file grows, we must make sure that the last page
      ** gets written at least once so that the disk file will be the correct
      ** size. If you do not write this page and the size of the file
      ** on the disk ends up being too small, that can lead to database
      ** corruption during the next transaction.
      */
    }else{
      TRACE3("DONT_WRITE page %d of %d\n", pgno, PAGERID(pPager));
      pPg->dirty = 0;
    }
  }
}

/*
** A call to this routine tells the pager that if a rollback occurs,
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
    assert( pPager->aInJournal!=0 );
    pPager->aInJournal[pPg->pgno/8] |= 1<<(pPg->pgno&7);
    pPg->inJournal = 1;
    if( pPager->stmtInUse ){
      pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
      page_add_to_stmt_list(pPg);
    }
    TRACE3("DONT_ROLLBACK page %d of %d\n", pPg->pgno, pPager->fd.h);
  }
  if( pPager->stmtInUse && !pPg->inStmt && (int)pPg->pgno<=pPager->stmtSize ){
    assert( pPg->inJournal || (int)pPg->pgno>pPager->origDbSize );
    assert( pPager->aInStmt!=0 );
    pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
    page_add_to_stmt_list(pPg);
  }







|







2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
    assert( pPager->aInJournal!=0 );
    pPager->aInJournal[pPg->pgno/8] |= 1<<(pPg->pgno&7);
    pPg->inJournal = 1;
    if( pPager->stmtInUse ){
      pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
      page_add_to_stmt_list(pPg);
    }
    TRACE3("DONT_ROLLBACK page %d of %d\n", pPg->pgno, PAGERID(pPager));
  }
  if( pPager->stmtInUse && !pPg->inStmt && (int)pPg->pgno<=pPager->stmtSize ){
    assert( pPg->inJournal || (int)pPg->pgno>pPager->origDbSize );
    assert( pPager->aInStmt!=0 );
    pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
    page_add_to_stmt_list(pPg);
  }
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
  if( pPager->errMask!=0 ){
    rc = pager_errcode(pPager);
    return rc;
  }
  if( pPager->state<PAGER_RESERVED ){
    return SQLITE_ERROR;
  }
  TRACE2("COMMIT %d\n", pPager->fd.h);
  if( MEMDB ){
    pPg = pager_get_all_dirty_pages(pPager);
    while( pPg ){
      clearHistory(PGHDR_TO_HIST(pPg, pPager));
      pPg->dirty = 0;
      pPg->inJournal = 0;
      pPg->inStmt = 0;







|







2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
  if( pPager->errMask!=0 ){
    rc = pager_errcode(pPager);
    return rc;
  }
  if( pPager->state<PAGER_RESERVED ){
    return SQLITE_ERROR;
  }
  TRACE2("COMMIT %d\n", PAGERID(pPager));
  if( MEMDB ){
    pPg = pager_get_all_dirty_pages(pPager);
    while( pPg ){
      clearHistory(PGHDR_TO_HIST(pPg, pPager));
      pPg->dirty = 0;
      pPg->inJournal = 0;
      pPg->inStmt = 0;
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
** process is writing trash into the journal file (SQLITE_CORRUPT) or
** unless a prior malloc() failed (SQLITE_NOMEM).  Appropriate error
** codes are returned for all these occasions.  Otherwise,
** SQLITE_OK is returned.
*/
int sqlite3pager_rollback(Pager *pPager){
  int rc;
  TRACE2("ROLLBACK %d\n", pPager->fd.h);
  if( MEMDB ){
    PgHdr *p;
    for(p=pPager->pAll; p; p=p->pNextAll){
      PgHistory *pHist;
      assert( !p->alwaysRollback );
      if( !p->dirty ){
        assert( !((PgHistory *)PGHDR_TO_HIST(p, pPager))->pOrig );
        assert( !((PgHistory *)PGHDR_TO_HIST(p, pPager))->pStmt );
        continue;
      }

      pHist = PGHDR_TO_HIST(p, pPager);
      if( pHist->pOrig ){
        memcpy(PGHDR_TO_DATA(p), pHist->pOrig, pPager->pageSize);
        TRACE3("ROLLBACK-PAGE %d of %d\n", p->pgno, pPager->fd.h);
      }else{
        TRACE3("PAGE %d is clean on %d\n", p->pgno, pPager->fd.h);
      }
      clearHistory(pHist);
      p->dirty = 0;
      p->inJournal = 0;
      p->inStmt = 0;
      p->pPrevStmt = p->pNextStmt = 0;








|














|

|







2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
** process is writing trash into the journal file (SQLITE_CORRUPT) or
** unless a prior malloc() failed (SQLITE_NOMEM).  Appropriate error
** codes are returned for all these occasions.  Otherwise,
** SQLITE_OK is returned.
*/
int sqlite3pager_rollback(Pager *pPager){
  int rc;
  TRACE2("ROLLBACK %d\n", PAGERID(pPager));
  if( MEMDB ){
    PgHdr *p;
    for(p=pPager->pAll; p; p=p->pNextAll){
      PgHistory *pHist;
      assert( !p->alwaysRollback );
      if( !p->dirty ){
        assert( !((PgHistory *)PGHDR_TO_HIST(p, pPager))->pOrig );
        assert( !((PgHistory *)PGHDR_TO_HIST(p, pPager))->pStmt );
        continue;
      }

      pHist = PGHDR_TO_HIST(p, pPager);
      if( pHist->pOrig ){
        memcpy(PGHDR_TO_DATA(p), pHist->pOrig, pPager->pageSize);
        TRACE3("ROLLBACK-PAGE %d of %d\n", p->pgno, PAGERID(pPager));
      }else{
        TRACE3("PAGE %d is clean on %d\n", p->pgno, PAGERID(pPager));
      }
      clearHistory(pHist);
      p->dirty = 0;
      p->inJournal = 0;
      p->inStmt = 0;
      p->pPrevStmt = p->pNextStmt = 0;

3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
** changes of a single SQL command within a larger transaction.
*/
int sqlite3pager_stmt_begin(Pager *pPager){
  int rc;
  char zTemp[SQLITE_TEMPNAME_SIZE];
  assert( !pPager->stmtInUse );
  assert( pPager->dbSize>=0 );
  TRACE2("STMT-BEGIN %d\n", pPager->fd.h);
  if( MEMDB ){
    pPager->stmtInUse = 1;
    pPager->stmtSize = pPager->dbSize;
    return SQLITE_OK;
  }
  if( !pPager->journalOpen ){
    pPager->stmtAutoopen = 1;







|







3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
** changes of a single SQL command within a larger transaction.
*/
int sqlite3pager_stmt_begin(Pager *pPager){
  int rc;
  char zTemp[SQLITE_TEMPNAME_SIZE];
  assert( !pPager->stmtInUse );
  assert( pPager->dbSize>=0 );
  TRACE2("STMT-BEGIN %d\n", PAGERID(pPager));
  if( MEMDB ){
    pPager->stmtInUse = 1;
    pPager->stmtSize = pPager->dbSize;
    return SQLITE_OK;
  }
  if( !pPager->journalOpen ){
    pPager->stmtAutoopen = 1;
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079

/*
** Commit a statement.
*/
int sqlite3pager_stmt_commit(Pager *pPager){
  if( pPager->stmtInUse ){
    PgHdr *pPg, *pNext;
    TRACE2("STMT-COMMIT %d\n", pPager->fd.h);
    if( !MEMDB ){
      sqlite3OsSeek(&pPager->stfd, 0);
      /* sqlite3OsTruncate(&pPager->stfd, 0); */
      sqliteFree( pPager->aInStmt );
      pPager->aInStmt = 0;
    }
    for(pPg=pPager->pStmt; pPg; pPg=pNext){







|







3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073

/*
** Commit a statement.
*/
int sqlite3pager_stmt_commit(Pager *pPager){
  if( pPager->stmtInUse ){
    PgHdr *pPg, *pNext;
    TRACE2("STMT-COMMIT %d\n", PAGERID(pPager));
    if( !MEMDB ){
      sqlite3OsSeek(&pPager->stfd, 0);
      /* sqlite3OsTruncate(&pPager->stfd, 0); */
      sqliteFree( pPager->aInStmt );
      pPager->aInStmt = 0;
    }
    for(pPg=pPager->pStmt; pPg; pPg=pNext){
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111

/*
** Rollback a statement.
*/
int sqlite3pager_stmt_rollback(Pager *pPager){
  int rc;
  if( pPager->stmtInUse ){
    TRACE2("STMT-ROLLBACK %d\n", pPager->fd.h);
    if( MEMDB ){
      PgHdr *pPg;
      for(pPg=pPager->pStmt; pPg; pPg=pPg->pNextStmt){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        if( pHist->pStmt ){
          memcpy(PGHDR_TO_DATA(pPg), pHist->pStmt, pPager->pageSize);
          sqliteFree(pHist->pStmt);







|







3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105

/*
** Rollback a statement.
*/
int sqlite3pager_stmt_rollback(Pager *pPager){
  int rc;
  if( pPager->stmtInUse ){
    TRACE2("STMT-ROLLBACK %d\n", PAGERID(pPager));
    if( MEMDB ){
      PgHdr *pPg;
      for(pPg=pPager->pStmt; pPg; pPg=pPg->pNextStmt){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        if( pHist->pStmt ){
          memcpy(PGHDR_TO_DATA(pPg), pHist->pStmt, pPager->pageSize);
          sqliteFree(pHist->pStmt);
3203
3204
3205
3206
3207
3208
3209



3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226



















3227
3228
3229
3230
3231
3232
3233
** passed to an sqlite3pager_sync() call.
**
** If parameter nTrunc is non-zero, then the pager file is truncated to
** nTrunc pages (this is used by auto-vacuum databases).
*/
int sqlite3pager_sync(Pager *pPager, const char *zMaster, Pgno nTrunc){
  int rc = SQLITE_OK;




  /* 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.
  */
  if( pPager->state!=PAGER_SYNCED && !MEMDB && pPager->dirtyCache ){
    PgHdr *pPg;
    assert( pPager->journalOpen );

    /* If a master journal file name has already been written to the
    ** journal file, then no sync is required. This happens when it is
    ** written, then the process fails to upgrade from a RESERVED to an
    ** EXCLUSIVE lock. The next time the process tries to commit the
    ** transaction the m-j name will have already been written.
    */
    if( !pPager->setMaster ){
      rc = pager_incr_changecounter(pPager);
      if( rc!=SQLITE_OK ) goto sync_exit;



















      rc = writeMasterJournal(pPager, zMaster);
      if( rc!=SQLITE_OK ) goto sync_exit;
      rc = syncJournal(pPager);
      if( rc!=SQLITE_OK ) goto sync_exit;
    }

#ifndef SQLITE_OMIT_AUTOVACUUM







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3249
** passed to an sqlite3pager_sync() call.
**
** If parameter nTrunc is non-zero, then the pager file is truncated to
** nTrunc pages (this is used by auto-vacuum databases).
*/
int sqlite3pager_sync(Pager *pPager, const char *zMaster, Pgno nTrunc){
  int rc = SQLITE_OK;

  TRACE4("DATABASE SYNC: File=%s zMaster=%s nTrunc=%d\n", 
      pPager->zFilename, zMaster, nTrunc);

  /* 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.
  */
  if( pPager->state!=PAGER_SYNCED && !MEMDB && pPager->dirtyCache ){
    PgHdr *pPg;
    assert( pPager->journalOpen );

    /* If a master journal file name has already been written to the
    ** journal file, then no sync is required. This happens when it is
    ** written, then the process fails to upgrade from a RESERVED to an
    ** EXCLUSIVE lock. The next time the process tries to commit the
    ** transaction the m-j name will have already been written.
    */
    if( !pPager->setMaster ){
      rc = pager_incr_changecounter(pPager);
      if( rc!=SQLITE_OK ) goto sync_exit;
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( nTrunc!=0 ){
        /* 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;
        void *pPage;
        for( i=nTrunc+1; i<=pPager->origDbSize; i++ ){
          if( !(pPager->aInJournal[i/8] & (1<<(i&7))) ){
            rc = sqlite3pager_get(pPager, i, &pPage);
            if( rc!=SQLITE_OK ) goto sync_exit;
            rc = sqlite3pager_write(pPage);
            sqlite3pager_unref(pPage);
            if( rc!=SQLITE_OK ) goto sync_exit;
          }
        } 
      }
#endif
      rc = writeMasterJournal(pPager, zMaster);
      if( rc!=SQLITE_OK ) goto sync_exit;
      rc = syncJournal(pPager);
      if( rc!=SQLITE_OK ) goto sync_exit;
    }

#ifndef SQLITE_OMIT_AUTOVACUUM
3275
3276
3277
3278
3279
3280
3281


3282
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3289
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3293
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3298
3299
  PgHdr *pPg = DATA_TO_PGHDR(pData);
  PgHdr *pPgOld; 
  int h;

  assert( !pPager->stmtInUse );
  assert( pPg->nRef>0 );



  /* Unlink pPg from it's hash-chain */
  unlinkHashChain(pPager, pPg);

  /* If the cache contains a page with page-number pgno exists, remove it
  ** from it's hash chain.
  */
  pPgOld = pager_lookup(pPager, pgno);
  if( pPgOld ){
    assert( pPgOld->nRef==0 );
    unlinkHashChain(pPager, pPgOld);
    pPgOld->dirty = 0;



  }

  /* Change the page number for pPg and insert it into the new hash-chain. */
  pPg->pgno = pgno;
  h = pager_hash(pgno);
  if( pPager->aHash[h] ){
    assert( pPager->aHash[h]->pPrevHash==0 );







>
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3291
3292
3293
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3306
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3314
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3316
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3318
3319
3320
  PgHdr *pPg = DATA_TO_PGHDR(pData);
  PgHdr *pPgOld; 
  int h;

  assert( !pPager->stmtInUse );
  assert( pPg->nRef>0 );

  TRACE4("MOVE %d page %d moves to %d\n", PAGERID(pPager), pPg->pgno, pgno);

  /* Unlink pPg from it's hash-chain */
  unlinkHashChain(pPager, pPg);

  /* If the cache contains a page with page-number pgno, remove it
  ** from it's hash chain.
  */
  pPgOld = pager_lookup(pPager, pgno);
  if( pPgOld ){
    assert( pPgOld->nRef==0 );
    unlinkHashChain(pPager, pPgOld);
    pPgOld->dirty = 0;
    if( pPgOld->needSync ){
      pPg->needSync = 1;
    }
  }

  /* Change the page number for pPg and insert it into the new hash-chain. */
  pPg->pgno = pgno;
  h = pager_hash(pgno);
  if( pPager->aHash[h] ){
    assert( pPager->aHash[h]->pPrevHash==0 );