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 1.565 2009/02/04 10:09:04 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"

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

**
** This function returns SQLITE_OK if everything is successful, an IO
** error code if the attempt to write to the sub-journal fails, or 
** SQLITE_NOMEM if a malloc fails while setting a bit in a savepoint
** bitvec.
*/
static int subjournalPage(PgHdr *pPg){
  int rc = SQLITE_OK;

  Pager *pPager = pPg->pPager;
  if( isOpen(pPager->sjfd) ){
    void *pData = pPg->pData;
    i64 offset = pPager->nSubRec*(4+pPager->pageSize);
    char *pData2 = CODEC2(pPager, pData, pPg->pgno, 7);
  
    PAGERTRACE(("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno));
  
    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);
    }
  }
  if( rc==SQLITE_OK ){
    pPager->nSubRec++;
    assert( pPager->nSavepoint>0 );
    rc = addToSavepointBitvecs(pPager, pPg->pgno);
    testcase( rc!=SQLITE_OK );
  }

# 2008 December 15
#
# 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: savepoint.test,v 1.12 2009/02/04 10:09:04 danielk1977 Exp $

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


#----------------------------------------------------------------------
# The following tests - savepoint-1.* - test that the SAVEPOINT, RELEASE

} {1 {column a is not unique}}
do_test savepoint-12.3 {
  sqlite3_get_autocommit db
} {1}
do_test savepoint-12.4 {
  execsql { SAVEPOINT one }
} {}

#-------------------------------------------------------------------------
# The following tests - savepoint-13.* - test the interaction of 
# savepoints and "journal_mode = off".
# 
do_test savepoint-13.1 {
  db close
  catch {file delete -force test.db}
  sqlite3 db test.db
  execsql {
    BEGIN;
      CREATE TABLE t1(a PRIMARY KEY, b);
      INSERT INTO t1 VALUES(1, 2);
    COMMIT;
    PRAGMA journal_mode = off;
  }
} {off}
do_test savepoint-13.2 {
  execsql {
    BEGIN;
    INSERT INTO t1 VALUES(3, 4);
    INSERT INTO t1 SELECT a+4,b+4  FROM t1;
    COMMIT;
  }
} {}
do_test savepoint-13.3 {
  execsql {
    BEGIN;
      INSERT INTO t1 VALUES(9, 10);
      SAVEPOINT s1;
        INSERT INTO t1 VALUES(11, 12);
    COMMIT;
  }
} {}
do_test savepoint-13.4 {
  execsql {
    BEGIN;
      INSERT INTO t1 VALUES(13, 14);
      SAVEPOINT s1;
        INSERT INTO t1 VALUES(15, 16);
      ROLLBACK TO s1;
    ROLLBACK;
    SELECT * FROM t1;
  }
} {1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16}

finish_test