SQLite

** 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 1.507 2008/11/21 03:23:43 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"

/*
** Macros for troubleshooting.  Normally turned off
*/

  while( i>0 ){
    cksum += aData[i];
    i -= 200;
  }
  return cksum;
}




/*
** Read a single page from the journal file opened on file descriptor
** jfd.  Playback this one page.
**
** The isMainJrnl flag is true if this is the main rollback journal and
** false for the statement journal.  The main rollback journal uses
** checksums - the statement journal does not.

    */
    void *pData;
    pData = pPg->pData;
    memcpy(pData, aData, pPager->pageSize);
    if( pPager->xReiniter ){
      pPager->xReiniter(pPg);
    }
    if( isMainJrnl ){
      sqlite3PcacheMakeClean(pPg);
    }
#ifdef SQLITE_CHECK_PAGES
    pPg->pageHash = pager_pagehash(pPg);
#endif
    /* If this was page 1, then restore the value of Pager.dbFileVers.
    ** Do this before any decoding. */
    if( pgno==1 ){
      memcpy(&pPager->dbFileVers, &((u8*)pData)[24],sizeof(pPager->dbFileVers));

      }
    }
  }
  /*NOTREACHED*/
  assert( 0 );

end_playback:
  /* There may be pages in cache that are dirty but which were not in
  ** the rollback journal.  Such pages would have been taken out of the
  ** freelist (and hence marked as DontRollback).  All such pages must
  ** be reinitialized.
  */
  if( rc==SQLITE_OK && pPager->xReiniter ){
    PgHdr *pDirty;     /* List of page that are still dirty */
    pDirty = sqlite3PcacheDirtyList(pPager->pPCache);
    while( pDirty ){
      pPager->xReiniter(pDirty);
      sqlite3PcacheMakeClean(pDirty);
      pDirty = pDirty->pDirty;
    }
  }
  if( rc==SQLITE_OK ){
    zMaster = pPager->pTmpSpace;
    rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
  }
  if( rc==SQLITE_OK ){
    rc = pager_end_transaction(pPager, zMaster[0]!='\0');
  }

      pPager->origDbSize = pPager->dbSize;
      rc = writeJournalHdr(pPager);
    }
  }
  assert( !pPager->journalOpen || pPager->journalOff>0 || rc!=SQLITE_OK );
  return rc;
}


















/*
** Mark a data page as writeable.  The page is written into the journal 
** if it is not there already.  This routine must be called before making
** changes to a page.
**
** The first time this routine is called, the pager creates a new

  if( rc ){
    return rc;
  }

  /* Mark the page as dirty.  If the page has already been written
  ** to the journal then we can return right away.
  */
  sqlite3PcacheMakeDirty(pPg);
  if( pageInJournal(pPg) && (pageInStatement(pPg) || pPager->stmtInUse==0) ){
    pPager->dirtyCache = 1;
    pPager->dbModified = 1;
  }else{

    /* If we get this far, it means that the page needs to be
    ** written to the transaction journal or the ckeckpoint journal

  }

  sqlite3PcacheMove(pPg, pgno);
  if( pPgOld ){
    sqlite3PcacheDrop(pPgOld);
  }

  sqlite3PcacheMakeDirty(pPg);
  pPager->dirtyCache = 1;
  pPager->dbModified = 1;

  if( needSyncPgno ){
    /* If needSyncPgno is non-zero, then the journal file needs to be 
    ** sync()ed before any data is written to database file page needSyncPgno.
    ** Currently, no such page exists in the page-cache and the 

        sqlite3BitvecClear(pPager->pInJournal, needSyncPgno);
      }
      return rc;
    }
    pPager->needSync = 1;
    assert( pPager->noSync==0 && !MEMDB );
    pPgHdr->flags |= PGHDR_NEED_SYNC;
    sqlite3PcacheMakeDirty(pPgHdr);
    sqlite3PagerUnref(pPgHdr);
  }

  return SQLITE_OK;
}
#endif

# 2008 November 20
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# When a transaction rolls back, make sure that dirty pages in the
# page cache which are not in the rollback journal are reinitialized
# in the btree layer.
#
# $Id: tkt35xx.test,v 1.1 2008/11/21 03:23:43 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_test tkt35xx-1.1 {
  execsql {
    PRAGMA auto_vacuum = 0;
    CREATE TABLE t1(a,b,c);
    CREATE INDEX i1 ON t1(c);
    INSERT INTO t1 VALUES(0, 0, zeroblob(676));
    INSERT INTO t1 VALUES(1, 1, zeroblob(676));
    DELETE FROM t1;
    BEGIN;
    INSERT INTO t1 VALUES(0, 0, zeroblob(676));
    INSERT INTO t1 VALUES(1, 1, zeroblob(676));
    ROLLBACK;
    INSERT INTO t1 VALUES(0, 0, zeroblob(676));
  }
  execsql {
    INSERT INTO t1 VALUES(1, 1, zeroblob(676));
  }
} {}