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 1.297 2007/03/26 12:26:27 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

/*
** Execute a rollback if a transaction is active and unlock the 
** database file. This is a no-op if the pager has already entered
** the error-state.
*/
static void pagerUnlockAndRollback(Pager *p){
  if( p->errCode ) return;
  assert( p->state>=PAGER_RESERVED || p->journalOpen==0 );
  if( p->state>=PAGER_RESERVED ){
    sqlite3PagerRollback(p);
  }
  pager_unlock(p);
  assert( p->errCode || !p->journalOpen || (p->exclusiveMode&&!p->journalOff) );
  assert( p->errCode || !p->stmtOpen || p->exclusiveMode );
}

        /* Playback and delete the journal.  Drop the database write
        ** lock and reacquire the read lock.
        */
        rc = pager_playback(pPager, 1);
        if( rc!=SQLITE_OK ){
          return pager_error(pPager, rc);
        }
        assert(pPager->state==PAGER_SHARED || 
            (pPager->exclusiveMode && pPager->state>PAGER_SHARED)
        );
      }

      if( pPager->pAll ){
        PgHdr *pPage1 = pager_lookup(pPager, 1);
        if( pPage1 ){
          unlinkHashChain(pPager, pPage1);
        }

          if( iChangeCount!=pPager->iChangeCount ){
            pager_reset(pPager);
          }
          pPager->iChangeCount = iChangeCount;
        }
      }
    }
    assert( pPager->exclusiveMode || pPager->state<=PAGER_SHARED );
    if( pPager->state==PAGER_UNLOCK ){
    pPager->state = PAGER_SHARED;
  }
  }

  return rc;
}

/*
** Acquire a page.
**

#***********************************************************************
# This file attempts to check the library in an out-of-memory situation.
# When compiled with -DSQLITE_DEBUG=1, the SQLite library accepts a special
# command (sqlite_malloc_fail N) which causes the N-th malloc to fail.  This
# special feature is used to see what happens in the library if a malloc
# were to really fail due to an out-of-memory situation.
#
# $Id: malloc.test,v 1.38 2007/03/26 12:26:27 danielk1977 Exp $

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

# Only run these tests if memory debugging is turned on.
#
if {[info command sqlite_malloc_stat]==""} {

}

# This block tests malloc() failures that occur while opening a 
# connection to a database.
do_malloc_test 10 -sqlprep {
  CREATE TABLE abc(a, b, c);
} -tclbody {
  db close
  sqlite3 db2 test.db
  db2 eval {SELECT * FROM sqlite_master}
  db2 close
} 

# This block tests malloc() failures that occur within calls to
# sqlite3_create_function().

#
#    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 runs all tests.
#
# $Id: quick.test,v 1.49 2007/03/26 12:26:27 danielk1977 Exp $

proc lshift {lvar} {
  upvar $lvar l
  set ret [lindex $l 0]
  set l [lrange $l 1 end]
  return $ret
}

  btree3.test
  btree4.test
  btree5.test
  btree6.test
  corrupt.test
  crash.test
  crash2.test
  exclusive3.test
  loadext.test
  malloc.test
  malloc2.test
  malloc3.test
  memleak.test
  misuse.test
  quick.test