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Overview
Comment:Allow a VACUUM operation to change the page-size in the same way as it can be used to change a database between auto-vacuum and normal mode. (CVS 4896)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1:871df0e7c36a88f175cfc63797745e52a1b1796b
User & Date: danielk1977 2008-03-20 11:04:21
Context
2008-03-20
14:03
Initial implementation of per-connection limits and the sqlite3_limit() API. The sqllimits1.test script crashes. SQLITE_LIMIT_PAGE_COUNT and SQLITE_LIMIT_VDBE_OP are currently ignored. (CVS 4897) check-in: 60c77882 user: drh tags: trunk
11:04
Allow a VACUUM operation to change the page-size in the same way as it can be used to change a database between auto-vacuum and normal mode. (CVS 4896) check-in: 871df0e7 user: danielk1977 tags: trunk
10:44
stick everything that sqlite links against into Libs.private (CVS 4895) check-in: 8b198617 user: vapier tags: trunk
Changes
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Changes to src/btree.c.

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** 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 1.440 2008/03/04 17:45:01 mlcreech Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

................................................................................
**
** SQLITE_OK is returned on success.  If the file is not a
** well-formed database file, then SQLITE_CORRUPT is returned.
** SQLITE_BUSY is returned if the database is locked.  SQLITE_NOMEM
** is returned if we run out of memory. 
*/
static int lockBtree(BtShared *pBt){
  int rc, pageSize;
  MemPage *pPage1;

  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pBt->pPage1 ) return SQLITE_OK;
  rc = sqlite3BtreeGetPage(pBt, 1, &pPage1, 0);
  if( rc!=SQLITE_OK ) return rc;
  

  /* Do some checking to help insure the file we opened really is
  ** a valid database file. 
  */
  rc = SQLITE_NOTADB;
  if( sqlite3PagerPagecount(pBt->pPager)>0 ){


    u8 *page1 = pPage1->aData;
    if( memcmp(page1, zMagicHeader, 16)!=0 ){
      goto page1_init_failed;
    }
    if( page1[18]>1 ){
      pBt->readOnly = 1;
    }
................................................................................
    pageSize = get2byte(&page1[16]);
    if( ((pageSize-1)&pageSize)!=0 || pageSize<512 ||
        (SQLITE_MAX_PAGE_SIZE<32768 && pageSize>SQLITE_MAX_PAGE_SIZE)
    ){
      goto page1_init_failed;
    }
    assert( (pageSize & 7)==0 );
    pBt->pageSize = pageSize;








    pBt->usableSize = pageSize - page1[20];




    if( pBt->usableSize<500 ){
      goto page1_init_failed;
    }


    pBt->maxEmbedFrac = page1[21];
    pBt->minEmbedFrac = page1[22];
    pBt->minLeafFrac = page1[23];
#ifndef SQLITE_OMIT_AUTOVACUUM
    pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
    pBt->incrVacuum = (get4byte(&page1[36 + 7*4])?1:0);
#endif
................................................................................
        goto trans_begun;
      }
    }
  }
#endif

  do {
    if( pBt->pPage1==0 ){
      rc = lockBtree(pBt);
    }

    if( rc==SQLITE_OK && wrflag ){
      if( pBt->readOnly ){
        rc = SQLITE_READONLY;
      }else{
................................................................................
      rc = autoVacuumCommit(pBt, &nTrunc); 
      if( rc!=SQLITE_OK ){
        sqlite3BtreeLeave(p);
        return rc;
      }
    }
#endif
    rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, nTrunc);
    sqlite3BtreeLeave(p);
  }
  return rc;
}

/*
** Commit the transaction currently in progress.
................................................................................
}

#ifndef SQLITE_OMIT_VACUUM
/*
** Copy the complete content of pBtFrom into pBtTo.  A transaction
** must be active for both files.
**
** The size of file pBtFrom may be reduced by this operation.
** If anything goes wrong, the transaction on pBtFrom is rolled back.




*/
static int btreeCopyFile(Btree *pTo, Btree *pFrom){
  int rc = SQLITE_OK;
  Pgno i, nPage, nToPage, iSkip;









  BtShared *pBtTo = pTo->pBt;
  BtShared *pBtFrom = pFrom->pBt;
  pBtTo->db = pTo->db;
  pBtFrom->db = pFrom->db;
  



  if( pTo->inTrans!=TRANS_WRITE || pFrom->inTrans!=TRANS_WRITE ){
    return SQLITE_ERROR;
  }
  if( pBtTo->pCursor ) return SQLITE_BUSY;



  nToPage = sqlite3PagerPagecount(pBtTo->pPager);
  nPage = sqlite3PagerPagecount(pBtFrom->pPager);
  iSkip = PENDING_BYTE_PAGE(pBtTo);
  for(i=1; rc==SQLITE_OK && i<=nPage; i++){
    DbPage *pDbPage;
    if( i==iSkip ) continue;
    rc = sqlite3PagerGet(pBtFrom->pPager, i, &pDbPage);

    if( rc ) break;
    rc = sqlite3PagerOverwrite(pBtTo->pPager, i, sqlite3PagerGetData(pDbPage));
    sqlite3PagerUnref(pDbPage);



  }


  /* If the file is shrinking, journal the pages that are being truncated
  ** so that they can be rolled back if the commit fails.






  */
  for(i=nPage+1; rc==SQLITE_OK && i<=nToPage; i++){

    DbPage *pDbPage;
    if( i==iSkip ) continue;
    rc = sqlite3PagerGet(pBtTo->pPager, i, &pDbPage);
    if( rc ) break;


    rc = sqlite3PagerWrite(pDbPage);
    sqlite3PagerDontWrite(pDbPage);




    /* Yeah.  It seems wierd to call DontWrite() right after Write().  But
    ** that is because the names of those procedures do not exactly 
    ** represent what they do.  Write() really means "put this page in the
    ** rollback journal and mark it as dirty so that it will be written
    ** to the database file later."  DontWrite() undoes the second part of
    ** that and prevents the page from being written to the database.  The
    ** page is still on the rollback journal, though.  And that is the whole
    ** point of this loop: to put pages on the rollback journal. */



    sqlite3PagerUnref(pDbPage);
  }
  if( !rc && nPage<nToPage ){



















































































































    rc = sqlite3PagerTruncate(pBtTo->pPager, nPage);
  }





  if( rc ){
    sqlite3BtreeRollback(pTo);
  }

  return rc;  
}
int sqlite3BtreeCopyFile(Btree *pTo, Btree *pFrom){
  int rc;
  sqlite3BtreeEnter(pTo);
  sqlite3BtreeEnter(pFrom);
  rc = btreeCopyFile(pTo, pFrom);







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** 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 1.441 2008/03/20 11:04:21 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

................................................................................
**
** SQLITE_OK is returned on success.  If the file is not a
** well-formed database file, then SQLITE_CORRUPT is returned.
** SQLITE_BUSY is returned if the database is locked.  SQLITE_NOMEM
** is returned if we run out of memory. 
*/
static int lockBtree(BtShared *pBt){
  int rc;
  MemPage *pPage1;

  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pBt->pPage1 ) return SQLITE_OK;
  rc = sqlite3BtreeGetPage(pBt, 1, &pPage1, 0);
  if( rc!=SQLITE_OK ) return rc;


  /* Do some checking to help insure the file we opened really is
  ** a valid database file. 
  */
  rc = SQLITE_NOTADB;
  if( sqlite3PagerPagecount(pBt->pPager)>0 ){
    int pageSize;
    int usableSize;
    u8 *page1 = pPage1->aData;
    if( memcmp(page1, zMagicHeader, 16)!=0 ){
      goto page1_init_failed;
    }
    if( page1[18]>1 ){
      pBt->readOnly = 1;
    }
................................................................................
    pageSize = get2byte(&page1[16]);
    if( ((pageSize-1)&pageSize)!=0 || pageSize<512 ||
        (SQLITE_MAX_PAGE_SIZE<32768 && pageSize>SQLITE_MAX_PAGE_SIZE)
    ){
      goto page1_init_failed;
    }
    assert( (pageSize & 7)==0 );
    usableSize = pageSize - page1[20];
    if( pageSize!=pBt->pageSize ){
      /* After reading the first page of the database assuming a page size
      ** of BtShared.pageSize, we have discovered that the page-size is
      ** actually pageSize. Unlock the database, leave pBt->pPage1 at
      ** zero and return SQLITE_OK. The caller will call this function
      ** again with the correct page-size.
      */
      releasePage(pPage1);
      pBt->usableSize = usableSize;
      pBt->pageSize = pageSize;
      sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
      return SQLITE_OK;
    }
    if( usableSize<500 ){
      goto page1_init_failed;
    }
    pBt->pageSize = pageSize;
    pBt->usableSize = usableSize;
    pBt->maxEmbedFrac = page1[21];
    pBt->minEmbedFrac = page1[22];
    pBt->minLeafFrac = page1[23];
#ifndef SQLITE_OMIT_AUTOVACUUM
    pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
    pBt->incrVacuum = (get4byte(&page1[36 + 7*4])?1:0);
#endif
................................................................................
        goto trans_begun;
      }
    }
  }
#endif

  do {
    while( rc==SQLITE_OK && pBt->pPage1==0 ){
      rc = lockBtree(pBt);
    }

    if( rc==SQLITE_OK && wrflag ){
      if( pBt->readOnly ){
        rc = SQLITE_READONLY;
      }else{
................................................................................
      rc = autoVacuumCommit(pBt, &nTrunc); 
      if( rc!=SQLITE_OK ){
        sqlite3BtreeLeave(p);
        return rc;
      }
    }
#endif
    rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, nTrunc, 0);
    sqlite3BtreeLeave(p);
  }
  return rc;
}

/*
** Commit the transaction currently in progress.
................................................................................
}

#ifndef SQLITE_OMIT_VACUUM
/*
** Copy the complete content of pBtFrom into pBtTo.  A transaction
** must be active for both files.
**
** The size of file pTo may be reduced by this operation.
** If anything goes wrong, the transaction on pTo is rolled back. 
**
** If successful, CommitPhaseOne() may be called on pTo before returning. 
** The caller should finish committing the transaction on pTo by calling
** sqlite3BtreeCommit().
*/
static int btreeCopyFile(Btree *pTo, Btree *pFrom){
  int rc = SQLITE_OK;
  Pgno i;

  Pgno nFromPage;     /* Number of pages in pFrom */
  Pgno nToPage;       /* Number of pages in pTo */
  Pgno nNewPage;      /* Number of pages in pTo after the copy */

  Pgno iSkip;         /* Pending byte page in pTo */
  int nToPageSize;    /* Page size of pTo in bytes */
  int nFromPageSize;  /* Page size of pFrom in bytes */

  BtShared *pBtTo = pTo->pBt;
  BtShared *pBtFrom = pFrom->pBt;
  pBtTo->db = pTo->db;
  pBtFrom->db = pFrom->db;

  nToPageSize = pBtTo->pageSize;
  nFromPageSize = pBtFrom->pageSize;

  if( pTo->inTrans!=TRANS_WRITE || pFrom->inTrans!=TRANS_WRITE ){
    return SQLITE_ERROR;
  }
  if( pBtTo->pCursor ){
    return SQLITE_BUSY;
  }

  nToPage = sqlite3PagerPagecount(pBtTo->pPager);
  nFromPage = sqlite3PagerPagecount(pBtFrom->pPager);
  iSkip = PENDING_BYTE_PAGE(pBtTo);





  /* Variable nNewPage is the number of pages required to store the
  ** contents of pFrom using the current page-size of pTo.

  */
  nNewPage = ((i64)nFromPage * (i64)nFromPageSize + (i64)nToPageSize - 1) / 
      (i64)nToPageSize;

  for(i=1; rc==SQLITE_OK && (i<=nToPage || i<=nNewPage); i++){



    /* Journal the original page.
    **
    ** iSkip is the page number of the locking page (PENDING_BYTE_PAGE)
    ** in database *pTo (before the copy). This page is never written 
    ** into the journal file. Unless i==iSkip or the page was not
    ** present in pTo before the copy operation, journal page i from pTo.
    */

    if( i!=iSkip && i<=nToPage ){
      DbPage *pDbPage;

      rc = sqlite3PagerGet(pBtTo->pPager, i, &pDbPage);
      if( rc ){
        break;
      }
      rc = sqlite3PagerWrite(pDbPage);

      if( rc ){
        break;
      }
      if( i>nFromPage ){
        /* Yeah.  It seems wierd to call DontWrite() right after Write(). But
        ** that is because the names of those procedures do not exactly 
        ** represent what they do.  Write() really means "put this page in the
        ** rollback journal and mark it as dirty so that it will be written
        ** to the database file later."  DontWrite() undoes the second part of
        ** that and prevents the page from being written to the database. The
        ** page is still on the rollback journal, though.  And that is the 
        ** whole point of this block: to put pages on the rollback journal. 
        */
        sqlite3PagerDontWrite(pDbPage);
      }
      sqlite3PagerUnref(pDbPage);
    }


    /* Overwrite the data in page i of the target database */
    if( rc==SQLITE_OK && i!=iSkip && i<=nNewPage ){

      DbPage *pToPage = 0;
      sqlite3_int64 iOff;

      rc = sqlite3PagerGet(pBtTo->pPager, i, &pToPage);
      if( rc==SQLITE_OK ){
        rc = sqlite3PagerWrite(pToPage);
      }

      for(
        iOff=(i-1)*nToPageSize; 
        rc==SQLITE_OK && iOff<i*nToPageSize; 
        iOff += nFromPageSize
      ){
        DbPage *pFromPage = 0;
        Pgno iFrom = (iOff/nFromPageSize)+1;

        if( iFrom==PENDING_BYTE_PAGE(pBtFrom) ){
          continue;
        }

        rc = sqlite3PagerGet(pBtFrom->pPager, iFrom, &pFromPage);
        if( rc==SQLITE_OK ){
          char *zTo = sqlite3PagerGetData(pToPage);
          char *zFrom = sqlite3PagerGetData(pFromPage);
          int nCopy;

          if( nFromPageSize>=nToPageSize ){
            zFrom += ((i-1)*nToPageSize - ((iFrom-1)*nFromPageSize));
            nCopy = nToPageSize;
          }else{
            zTo += (((iFrom-1)*nFromPageSize) - (i-1)*nToPageSize);
            nCopy = nFromPageSize;
          }

          memcpy(zTo, zFrom, nCopy);
	  sqlite3PagerUnref(pFromPage);
        }
      }

      if( pToPage ) sqlite3PagerUnref(pToPage);
    }
  }

  /* If things have worked so far, the database file may need to be 
  ** truncated. The complex part is that it may need to be truncated to
  ** a size that is not an integer multiple of nToPageSize - the current
  ** page size used by the pager associated with B-Tree pTo.
  **
  ** For example, say the page-size of pTo is 2048 bytes and the original 
  ** number of pages is 5 (10 KB file). If pFrom has a page size of 1024 
  ** bytes and 9 pages, then the file needs to be truncated to 9KB.
  */
  if( rc==SQLITE_OK ){
    if( nFromPageSize!=nToPageSize ){
      sqlite3_file *pFile = sqlite3PagerFile(pBtTo->pPager);
      i64 iSize = (i64)nFromPageSize * (i64)nFromPage;
      i64 iNow = (i64)((nToPage>nNewPage)?nToPage:nNewPage) * (i64)nToPageSize; 
      i64 iPending = ((i64)PENDING_BYTE_PAGE(pBtTo)-1) *(i64)nToPageSize;
  
      assert( iSize<=iNow );
  
      /* Commit phase one syncs the journal file associated with pTo 
      ** containing the original data. It does not sync the database file
      ** itself. After doing this it is safe to use OsTruncate() and other
      ** file APIs on the database file directly.
      */
      pBtTo->db = pTo->db;
      rc = sqlite3PagerCommitPhaseOne(pBtTo->pPager, 0, 0, 1);
      if( iSize<iNow && rc==SQLITE_OK ){
        rc = sqlite3OsTruncate(pFile, iSize);
      }
  
      /* The loop that copied data from database pFrom to pTo did not
      ** populate the locking page of database pTo. If the page-size of
      ** pFrom is smaller than that of pTo, this means some data will
      ** not have been copied. 
      **
      ** This block copies the missing data from database pFrom to pTo 
      ** using file APIs. This is safe because at this point we know that
      ** all of the original data from pTo has been synced into the 
      ** journal file. At this point it would be safe to do anything at
      ** all to the database file except truncate it to zero bytes.
      */
      if( rc==SQLITE_OK && nFromPageSize<nToPageSize && iSize>iPending){
        i64 iOff;
        for(
          iOff=iPending; 
          rc==SQLITE_OK && iOff<(iPending+nToPageSize); 
          iOff += nFromPageSize
        ){
          DbPage *pFromPage = 0;
          Pgno iFrom = (iOff/nFromPageSize)+1;
  
          if( iFrom==PENDING_BYTE_PAGE(pBtFrom) || iFrom>nFromPage ){
            continue;
          }
  
          rc = sqlite3PagerGet(pBtFrom->pPager, iFrom, &pFromPage);
          if( rc==SQLITE_OK ){
            char *zFrom = sqlite3PagerGetData(pFromPage);
  	  rc = sqlite3OsWrite(pFile, zFrom, nFromPageSize, iOff);
            sqlite3PagerUnref(pFromPage);
          }
        }
      }
  
      /* Sync the database file */
      if( rc==SQLITE_OK ){
        rc = sqlite3PagerSync(pBtTo->pPager);
      }
    }else{
      rc = sqlite3PagerTruncate(pBtTo->pPager, nNewPage);
    }
    if( rc==SQLITE_OK ){
      pBtTo->pageSizeFixed = 0;
    }
  }

  if( rc ){
    sqlite3BtreeRollback(pTo);
  }

  return rc;  
}
int sqlite3BtreeCopyFile(Btree *pTo, Btree *pFrom){
  int rc;
  sqlite3BtreeEnter(pTo);
  sqlite3BtreeEnter(pFrom);
  rc = btreeCopyFile(pTo, pFrom);

Changes to src/main.c.

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
...
967
968
969
970
971
972
973

974
975
976
977
978
979
980
**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.424 2008/03/19 16:08:54 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif

................................................................................
  db->errMask = 0xff;
  db->priorNewRowid = 0;
  db->nDb = 2;
  db->magic = SQLITE_MAGIC_BUSY;
  db->aDb = db->aDbStatic;
  db->autoCommit = 1;
  db->nextAutovac = -1;

  db->flags |= SQLITE_ShortColNames
#if SQLITE_DEFAULT_FILE_FORMAT<4
                 | SQLITE_LegacyFileFmt
#endif
#ifdef SQLITE_ENABLE_LOAD_EXTENSION
                 | SQLITE_LoadExtension
#endif







|







 







>







10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
...
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.425 2008/03/20 11:04:21 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif

................................................................................
  db->errMask = 0xff;
  db->priorNewRowid = 0;
  db->nDb = 2;
  db->magic = SQLITE_MAGIC_BUSY;
  db->aDb = db->aDbStatic;
  db->autoCommit = 1;
  db->nextAutovac = -1;
  db->nextPagesize = 0;
  db->flags |= SQLITE_ShortColNames
#if SQLITE_DEFAULT_FILE_FORMAT<4
                 | SQLITE_LegacyFileFmt
#endif
#ifdef SQLITE_ENABLE_LOAD_EXTENSION
                 | SQLITE_LoadExtension
#endif

Changes to src/pager.c.

14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
....
4496
4497
4498
4499
4500
4501
4502











4503
4504
4505
4506
4507
4508
4509
....
4513
4514
4515
4516
4517
4518
4519





4520
4521





4522
4523
4524
4525
4526
4527
4528
....
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
** 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 1.419 2008/03/20 04:45:49 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include <assert.h>
#include <string.h>

/*
................................................................................

    /* Release the page reference. */
    sqlite3PagerUnref(pPgHdr);
    pPager->changeCountDone = 1;
  }
  return rc;
}












/*
** Sync the database file for the pager pPager. zMaster points to the name
** of a master journal file that should be written into the individual
** journal file. zMaster may be NULL, which is interpreted as no master
** journal (a single database transaction).
**
................................................................................
** master journal file if specified).
**
** Note that if zMaster==NULL, this does not overwrite a previous value
** passed to an sqlite3PagerCommitPhaseOne() call.
**
** If parameter nTrunc is non-zero, then the pager file is truncated to
** nTrunc pages (this is used by auto-vacuum databases).





*/
int sqlite3PagerCommitPhaseOne(Pager *pPager, const char *zMaster, Pgno nTrunc){





  int rc = SQLITE_OK;

  PAGERTRACE4("DATABASE SYNC: File=%s zMaster=%s nTrunc=%d\n", 
      pPager->zFilename, zMaster, nTrunc);
  pagerEnter(pPager);

  /* If this is an in-memory db, or no pages have been written to, or this
................................................................................
      ** is made to use an invalid dirty list.
      */
      goto sync_exit;
    }
    pPager->pDirty = 0;

    /* Sync the database file. */
    if( !pPager->noSync ){
      rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
    }
    IOTRACE(("DBSYNC %p\n", pPager))

    pPager->state = PAGER_SYNCED;
  }else if( MEMDB && nTrunc!=0 ){
    rc = sqlite3PagerTruncate(pPager, nTrunc);







|







 







>
>
>
>
>
>
>
>
>
>
>







 







>
>
>
>
>

|
>
>
>
>
>







 







|







14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
....
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
....
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
....
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
** 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 1.420 2008/03/20 11:04:21 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include <assert.h>
#include <string.h>

/*
................................................................................

    /* Release the page reference. */
    sqlite3PagerUnref(pPgHdr);
    pPager->changeCountDone = 1;
  }
  return rc;
}

/*
** Sync the pager file to disk.
*/
int sqlite3PagerSync(Pager *pPager){
  int rc;
  pagerEnter(pPager);
  rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
  pagerLeave(pPager);
  return rc;
}

/*
** Sync the database file for the pager pPager. zMaster points to the name
** of a master journal file that should be written into the individual
** journal file. zMaster may be NULL, which is interpreted as no master
** journal (a single database transaction).
**
................................................................................
** master journal file if specified).
**
** Note that if zMaster==NULL, this does not overwrite a previous value
** passed to an sqlite3PagerCommitPhaseOne() call.
**
** If parameter nTrunc is non-zero, then the pager file is truncated to
** nTrunc pages (this is used by auto-vacuum databases).
**
** If the final parameter - noSync - is true, then the database file itself
** is not synced. The caller must call sqlite3PagerSync() directly to
** sync the database file before calling CommitPhaseTwo() to delete the
** journal file in this case.
*/
int sqlite3PagerCommitPhaseOne(
  Pager *pPager, 
  const char *zMaster, 
  Pgno nTrunc,
  int noSync
){
  int rc = SQLITE_OK;

  PAGERTRACE4("DATABASE SYNC: File=%s zMaster=%s nTrunc=%d\n", 
      pPager->zFilename, zMaster, nTrunc);
  pagerEnter(pPager);

  /* If this is an in-memory db, or no pages have been written to, or this
................................................................................
      ** is made to use an invalid dirty list.
      */
      goto sync_exit;
    }
    pPager->pDirty = 0;

    /* Sync the database file. */
    if( !pPager->noSync && !noSync ){
      rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
    }
    IOTRACE(("DBSYNC %p\n", pPager))

    pPager->state = PAGER_SYNCED;
  }else if( MEMDB && nTrunc!=0 ){
    rc = sqlite3PagerTruncate(pPager, nTrunc);

Changes to src/pager.h.

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
..
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
..
91
92
93
94
95
96
97

98
99
100
101
102
103
104
**    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 1.69 2008/02/02 20:47:38 drh Exp $
*/

#ifndef _PAGER_H_
#define _PAGER_H_

/*
** The type used to represent a page number.  The first page in a file
................................................................................
int sqlite3PagerRef(DbPage*);
int sqlite3PagerUnref(DbPage*);
int sqlite3PagerWrite(DbPage*);
int sqlite3PagerOverwrite(Pager *pPager, Pgno pgno, void*);
int sqlite3PagerPagecount(Pager*);
int sqlite3PagerTruncate(Pager*,Pgno);
int sqlite3PagerBegin(DbPage*, int exFlag);
int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, Pgno);
int sqlite3PagerCommitPhaseTwo(Pager*);
int sqlite3PagerRollback(Pager*);
int sqlite3PagerIsreadonly(Pager*);
int sqlite3PagerStmtBegin(Pager*);
int sqlite3PagerStmtCommit(Pager*);
int sqlite3PagerStmtRollback(Pager*);
void sqlite3PagerDontRollback(DbPage*);
................................................................................
const char *sqlite3PagerJournalname(Pager*);
int sqlite3PagerNosync(Pager*);
int sqlite3PagerMovepage(Pager*,DbPage*,Pgno);
void *sqlite3PagerGetData(DbPage *); 
void *sqlite3PagerGetExtra(DbPage *); 
int sqlite3PagerLockingMode(Pager *, int);
void *sqlite3PagerTempSpace(Pager*);


#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
  int sqlite3PagerReleaseMemory(int);
#endif

#ifdef SQLITE_HAS_CODEC
  void sqlite3PagerSetCodec(Pager*,void*(*)(void*,void*,Pgno,int),void*);







|







 







|







 







>







9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
..
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
..
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
**    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 1.70 2008/03/20 11:04:21 danielk1977 Exp $
*/

#ifndef _PAGER_H_
#define _PAGER_H_

/*
** The type used to represent a page number.  The first page in a file
................................................................................
int sqlite3PagerRef(DbPage*);
int sqlite3PagerUnref(DbPage*);
int sqlite3PagerWrite(DbPage*);
int sqlite3PagerOverwrite(Pager *pPager, Pgno pgno, void*);
int sqlite3PagerPagecount(Pager*);
int sqlite3PagerTruncate(Pager*,Pgno);
int sqlite3PagerBegin(DbPage*, int exFlag);
int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, Pgno, int);
int sqlite3PagerCommitPhaseTwo(Pager*);
int sqlite3PagerRollback(Pager*);
int sqlite3PagerIsreadonly(Pager*);
int sqlite3PagerStmtBegin(Pager*);
int sqlite3PagerStmtCommit(Pager*);
int sqlite3PagerStmtRollback(Pager*);
void sqlite3PagerDontRollback(DbPage*);
................................................................................
const char *sqlite3PagerJournalname(Pager*);
int sqlite3PagerNosync(Pager*);
int sqlite3PagerMovepage(Pager*,DbPage*,Pgno);
void *sqlite3PagerGetData(DbPage *); 
void *sqlite3PagerGetExtra(DbPage *); 
int sqlite3PagerLockingMode(Pager *, int);
void *sqlite3PagerTempSpace(Pager*);
int sqlite3PagerSync(Pager *pPager);

#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
  int sqlite3PagerReleaseMemory(int);
#endif

#ifdef SQLITE_HAS_CODEC
  void sqlite3PagerSetCodec(Pager*,void*(*)(void*,void*,Pgno,int),void*);

Changes to src/pragma.c.

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
346
347
348
349
350
351
352

353
354
355
356
357
358
359
360
**    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 file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.171 2008/03/19 00:21:31 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
#if !defined(SQLITE_OMIT_PRAGMA) && !defined(SQLITE_OMIT_PARSER)
................................................................................
    if( !zRight ){
      int size = pBt ? sqlite3BtreeGetPageSize(pBt) : 0;
      returnSingleInt(pParse, "page_size", size);
    }else{
      /* Malloc may fail when setting the page-size, as there is an internal
      ** buffer that the pager module resizes using sqlite3_realloc().
      */

      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, atoi(zRight), -1) ){
        db->mallocFailed = 1;
      }
    }
  }else

  /*
  **  PRAGMA [database.]max_page_count







|







 







>
|







7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
**    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 file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.172 2008/03/20 11:04:21 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
#if !defined(SQLITE_OMIT_PRAGMA) && !defined(SQLITE_OMIT_PARSER)
................................................................................
    if( !zRight ){
      int size = pBt ? sqlite3BtreeGetPageSize(pBt) : 0;
      returnSingleInt(pParse, "page_size", size);
    }else{
      /* Malloc may fail when setting the page-size, as there is an internal
      ** buffer that the pager module resizes using sqlite3_realloc().
      */
      db->nextPagesize = atoi(zRight);
      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize, -1) ){
        db->mallocFailed = 1;
      }
    }
  }else

  /*
  **  PRAGMA [database.]max_page_count

Changes to src/sqliteInt.h.

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
571
572
573
574
575
576
577

578
579
580
581
582
583
584
**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.675 2008/03/20 00:32:20 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if it was run
** (otherwise we get an empty default).
................................................................................
  int openFlags;                /* Flags passed to sqlite3_vfs.xOpen() */
  int errCode;                  /* Most recent error code (SQLITE_*) */
  int errMask;                  /* & result codes with this before returning */
  u8 autoCommit;                /* The auto-commit flag. */
  u8 temp_store;                /* 1: file 2: memory 0: default */
  u8 mallocFailed;              /* True if we have seen a malloc failure */
  signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */

  int nTable;                   /* Number of tables in the database */
  CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
  i64 lastRowid;                /* ROWID of most recent insert (see above) */
  i64 priorNewRowid;            /* Last randomly generated ROWID */
  int magic;                    /* Magic number for detect library misuse */
  int nChange;                  /* Value returned by sqlite3_changes() */
  int nTotalChange;             /* Value returned by sqlite3_total_changes() */







|







 







>







7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.676 2008/03/20 11:04:21 danielk1977 Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if it was run
** (otherwise we get an empty default).
................................................................................
  int openFlags;                /* Flags passed to sqlite3_vfs.xOpen() */
  int errCode;                  /* Most recent error code (SQLITE_*) */
  int errMask;                  /* & result codes with this before returning */
  u8 autoCommit;                /* The auto-commit flag. */
  u8 temp_store;                /* 1: file 2: memory 0: default */
  u8 mallocFailed;              /* True if we have seen a malloc failure */
  signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
  int nextPagesize;             /* Pagesize after VACUUM if >0 */
  int nTable;                   /* Number of tables in the database */
  CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
  i64 lastRowid;                /* ROWID of most recent insert (see above) */
  i64 priorNewRowid;            /* Last randomly generated ROWID */
  int magic;                    /* Magic number for detect library misuse */
  int nChange;                  /* Value returned by sqlite3_changes() */
  int nTotalChange;             /* Value returned by sqlite3_total_changes() */

Changes to src/test2.c.

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
...
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the pager.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test2.c,v 1.55 2008/03/19 00:21:31 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>

/*
................................................................................
  int rc;
  if( argc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID\"", 0);
    return TCL_ERROR;
  }
  pPager = sqlite3TextToPtr(argv[1]);
  rc = sqlite3PagerCommitPhaseOne(pPager, 0, 0);
  if( rc!=SQLITE_OK ){
    Tcl_AppendResult(interp, errorName(rc), 0);
    return TCL_ERROR;
  }
  rc = sqlite3PagerCommitPhaseTwo(pPager);
  if( rc!=SQLITE_OK ){
    Tcl_AppendResult(interp, errorName(rc), 0);







|







 







|







9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
...
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the pager.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test2.c,v 1.56 2008/03/20 11:04:21 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>

/*
................................................................................
  int rc;
  if( argc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID\"", 0);
    return TCL_ERROR;
  }
  pPager = sqlite3TextToPtr(argv[1]);
  rc = sqlite3PagerCommitPhaseOne(pPager, 0, 0, 0);
  if( rc!=SQLITE_OK ){
    Tcl_AppendResult(interp, errorName(rc), 0);
    return TCL_ERROR;
  }
  rc = sqlite3PagerCommitPhaseTwo(pPager);
  if( rc!=SQLITE_OK ){
    Tcl_AppendResult(interp, errorName(rc), 0);

Changes to src/vacuum.c.

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**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.76 2008/01/03 00:01:25 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/*
** Execute zSql on database db. Return an error code.
................................................................................
int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
  int rc = SQLITE_OK;     /* Return code from service routines */
  Btree *pMain;           /* The database being vacuumed */
  Btree *pTemp;           /* The temporary database we vacuum into */
  char *zSql = 0;         /* SQL statements */
  int saved_flags;        /* Saved value of the db->flags */
  Db *pDb = 0;            /* Database to detach at end of vacuum */


  /* Save the current value of the write-schema flag before setting it. */
  saved_flags = db->flags;
  db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;

  if( !db->autoCommit ){
    sqlite3SetString(pzErrMsg, "cannot VACUUM from within a transaction", 
................................................................................
  */
  zSql = "ATTACH '' AS vacuum_db;";
  rc = execSql(db, zSql);
  if( rc!=SQLITE_OK ) goto end_of_vacuum;
  pDb = &db->aDb[db->nDb-1];
  assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
  pTemp = db->aDb[db->nDb-1].pBt;


  sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain),
     sqlite3BtreeGetReserve(pMain));

  if( db->mallocFailed ){

    rc = SQLITE_NOMEM;
    goto end_of_vacuum;
  }
  assert( sqlite3BtreeGetPageSize(pTemp)==sqlite3BtreeGetPageSize(pMain) );
  rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
  if( rc!=SQLITE_OK ){
    goto end_of_vacuum;
  }

#ifndef SQLITE_OMIT_AUTOVACUUM
  sqlite3BtreeSetAutoVacuum(pTemp, db->nextAutovac>=0 ? db->nextAutovac :
................................................................................

    rc = sqlite3BtreeCopyFile(pMain, pTemp);
    if( rc!=SQLITE_OK ) goto end_of_vacuum;
    rc = sqlite3BtreeCommit(pTemp);
    if( rc!=SQLITE_OK ) goto end_of_vacuum;
    rc = sqlite3BtreeCommit(pMain);
  }





end_of_vacuum:
  /* Restore the original value of db->flags */
  db->flags = saved_flags;

  /* Currently there is an SQL level transaction open on the vacuum
  ** database. No locks are held on any other files (since the main file







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**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.77 2008/03/20 11:04:21 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/*
** Execute zSql on database db. Return an error code.
................................................................................
int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
  int rc = SQLITE_OK;     /* Return code from service routines */
  Btree *pMain;           /* The database being vacuumed */
  Btree *pTemp;           /* The temporary database we vacuum into */
  char *zSql = 0;         /* SQL statements */
  int saved_flags;        /* Saved value of the db->flags */
  Db *pDb = 0;            /* Database to detach at end of vacuum */
  int nRes;

  /* Save the current value of the write-schema flag before setting it. */
  saved_flags = db->flags;
  db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;

  if( !db->autoCommit ){
    sqlite3SetString(pzErrMsg, "cannot VACUUM from within a transaction", 
................................................................................
  */
  zSql = "ATTACH '' AS vacuum_db;";
  rc = execSql(db, zSql);
  if( rc!=SQLITE_OK ) goto end_of_vacuum;
  pDb = &db->aDb[db->nDb-1];
  assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
  pTemp = db->aDb[db->nDb-1].pBt;

  nRes = sqlite3BtreeGetReserve(pMain);
  if( sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain), nRes)

   || sqlite3BtreeSetPageSize(pTemp, db->nextPagesize, nRes)
   || db->mallocFailed 
  ){
    rc = SQLITE_NOMEM;
    goto end_of_vacuum;
  }

  rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
  if( rc!=SQLITE_OK ){
    goto end_of_vacuum;
  }

#ifndef SQLITE_OMIT_AUTOVACUUM
  sqlite3BtreeSetAutoVacuum(pTemp, db->nextAutovac>=0 ? db->nextAutovac :
................................................................................

    rc = sqlite3BtreeCopyFile(pMain, pTemp);
    if( rc!=SQLITE_OK ) goto end_of_vacuum;
    rc = sqlite3BtreeCommit(pTemp);
    if( rc!=SQLITE_OK ) goto end_of_vacuum;
    rc = sqlite3BtreeCommit(pMain);
  }

  if( rc==SQLITE_OK ){
    rc = sqlite3BtreeSetPageSize(pMain, sqlite3BtreeGetPageSize(pTemp), nRes);
  }

end_of_vacuum:
  /* Restore the original value of db->flags */
  db->flags = saved_flags;

  /* Currently there is an SQL level transaction open on the vacuum
  ** database. No locks are held on any other files (since the main file