if( pPager->noSync ){
    rc = SQLITE_OK;
  }else{
    rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
  }
  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).
**

  if( pPager->noSync ){
    rc = SQLITE_OK;
  }else{
    rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
  }
  return rc;
}

/*
** This function may only be called while a write-transaction is active in
** rollback. If the connection is in WAL mode, this call is a no-op. 
** Otherwise, if the connection does not already have an EXCLUSIVE lock on 
** the database file, an attempt is made to obtain one.
**
** If the EXCLUSIVE lock is already held or the attempt to obtain it is
** successful, or the connection is in WAL mode, SQLITE_OK is returned.
** Otherwise, either SQLITE_BUSY or an SQLITE_IOERR_XXX error code is 
** returned.
*/
int sqlite3PagerExclusiveLock(Pager *pPager){
  int rc = SQLITE_OK;
  assert( pPager->state>=PAGER_RESERVED );
  if( 0==pagerUseWal(pPager) ){
    rc = pager_wait_on_lock(pPager, PAGER_EXCLUSIVE);
  }
  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).
**

void *sqlite3PagerGetData(DbPage *); 
void *sqlite3PagerGetExtra(DbPage *); 

/* Functions used to manage pager transactions and savepoints. */
int sqlite3PagerPagecount(Pager*, int*);
int sqlite3PagerBegin(Pager*, int exFlag, int);
int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);

int sqlite3PagerSync(Pager *pPager);
int sqlite3PagerCommitPhaseTwo(Pager*);
int sqlite3PagerRollback(Pager*);
int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
int sqlite3PagerSharedLock(Pager *pPager);

void *sqlite3PagerGetData(DbPage *); 
void *sqlite3PagerGetExtra(DbPage *); 

/* Functions used to manage pager transactions and savepoints. */
int sqlite3PagerPagecount(Pager*, int*);
int sqlite3PagerBegin(Pager*, int exFlag, int);
int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
int sqlite3PagerExclusiveLock(Pager*);
int sqlite3PagerSync(Pager *pPager);
int sqlite3PagerCommitPhaseTwo(Pager*);
int sqlite3PagerRollback(Pager*);
int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
int sqlite3PagerSharedLock(Pager *pPager);

  /* Before doing anything else, call the xSync() callback for any
  ** virtual module tables written in this transaction. This has to
  ** be done before determining whether a master journal file is 
  ** required, as an xSync() callback may add an attached database
  ** to the transaction.
  */
  rc = sqlite3VtabSync(db, &p->zErrMsg);
  if( rc!=SQLITE_OK ){
    return rc;
  }

  /* This loop determines (a) if the commit hook should be invoked and
  ** (b) how many database files have open write transactions, not 
  ** including the temp database. (b) is important because if more than 
  ** one database file has an open write transaction, a master journal
  ** file is required for an atomic commit.
  */ 
  for(i=0; i<db->nDb; i++){ 
    Btree *pBt = db->aDb[i].pBt;
    if( sqlite3BtreeIsInTrans(pBt) ){
      needXcommit = 1;
      if( i!=1 ) nTrans++;

    }



  }

  /* If there are any write-transactions at all, invoke the commit hook */
  if( needXcommit && db->xCommitCallback ){
    rc = db->xCommitCallback(db->pCommitArg);
    if( rc ){
      return SQLITE_CONSTRAINT;
................................................................................
    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
      Btree *pBt = db->aDb[i].pBt;
      if( pBt ){
        rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
      }
    }
    sqlite3OsCloseFree(pMaster);

    if( rc!=SQLITE_OK ){
      sqlite3DbFree(db, zMaster);
      return rc;
    }

    /* Delete the master journal file. This commits the transaction. After
    ** doing this the directory is synced again before any individual

  /* Before doing anything else, call the xSync() callback for any
  ** virtual module tables written in this transaction. This has to
  ** be done before determining whether a master journal file is 
  ** required, as an xSync() callback may add an attached database
  ** to the transaction.
  */
  rc = sqlite3VtabSync(db, &p->zErrMsg);




  /* This loop determines (a) if the commit hook should be invoked and
  ** (b) how many database files have open write transactions, not 
  ** including the temp database. (b) is important because if more than 
  ** one database file has an open write transaction, a master journal
  ** file is required for an atomic commit.
  */ 
  for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
    Btree *pBt = db->aDb[i].pBt;
    if( sqlite3BtreeIsInTrans(pBt) ){
      needXcommit = 1;
      if( i!=1 ) nTrans++;
      rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));
    }
  }
  if( rc!=SQLITE_OK ){
    return rc;
  }

  /* If there are any write-transactions at all, invoke the commit hook */
  if( needXcommit && db->xCommitCallback ){
    rc = db->xCommitCallback(db->pCommitArg);
    if( rc ){
      return SQLITE_CONSTRAINT;
................................................................................
    for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
      Btree *pBt = db->aDb[i].pBt;
      if( pBt ){
        rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
      }
    }
    sqlite3OsCloseFree(pMaster);
    assert( rc!=SQLITE_BUSY );
    if( rc!=SQLITE_OK ){
      sqlite3DbFree(db, zMaster);
      return rc;
    }

    /* Delete the master journal file. This commits the transaction. After
    ** doing this the directory is synced again before any individual

# 2010 July 29
#
# 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.
#
#***********************************************************************
#

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

foreach f [glob -nocomplain test.db*mj*] { file delete -force $f }
file delete -force test.db2

do_test tkt-f3e5abed55-1.1 {
  execsql {
    ATTACH 'test.db2' AS aux;
    CREATE TABLE main.t1(a, b);
    CREATE TABLE aux.t2(c, d);
  }
} {}

do_test tkt-f3e5abed55-1.2 {
  glob -nocomplain test.db*mj*
} {}

do_test tkt-f3e5abed55-1.3 {
  sqlite3 db2 test.db
  execsql { BEGIN; SELECT * FROM t1 } db2
} {}

do_test tkt-f3e5abed55-1.4 {
  execsql {
    BEGIN;
      INSERT INTO t1 VALUES(1, 2);
      INSERT INTO t2 VALUES(1, 2);
  }
  catchsql COMMIT
} {1 {database is locked}}

do_test tkt-f3e5abed55-1.5 {
  execsql COMMIT db2
  execsql COMMIT
} {}

do_test tkt-f3e5abed55-1.6 {
  glob -nocomplain test.db*mj*
} {}
foreach f [glob -nocomplain test.db*mj*] { file delete -force $f }
db close
db2 close



# Set up a testvfs so that the next time SQLite tries to delete the
# file "test.db-journal", a snapshot of the current file-system contents
# is taken.
#
testvfs tvfs -default 1
tvfs script xDelete
tvfs filter xDelete
proc xDelete {method file args} {
  if {[file tail $file] == "test.db-journal"} {
    faultsim_save
    tvfs filter {}
  }
  return "SQLITE_OK"
}

sqlite3 db  test.db
sqlite3 db2 test.db
do_test tkt-f3e5abed55-2.1 {
  execsql {
    ATTACH 'test.db2' AS aux;
    BEGIN;
      INSERT INTO t1 VALUES(3, 4);
      INSERT INTO t2 VALUES(3, 4);
  }
} {}
do_test tkt-f3e5abed55-2.2 {
  execsql { BEGIN; SELECT * FROM t1 } db2
} {1 2}
do_test tkt-f3e5abed55-2.3 {
  catchsql COMMIT
} {1 {database is locked}}

do_test tkt-f3e5abed55-2.4 {
  execsql COMMIT db2
  execsql {
    COMMIT;
    SELECT * FROM t1;
    SELECT * FROM t2;
  }
} {1 2 3 4 1 2 3 4}
do_test tkt-f3e5abed55-2.5 {
  db close
  db2 close
  faultsim_restore_and_reopen
  execsql {
    ATTACH 'test.db2' AS aux;
    SELECT * FROM t1;
    SELECT * FROM t2;
  }
} {1 2 3 4 1 2 3 4}


finish_test