**
**    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: test_async.c,v 1.52 2009/03/25 16:51:43 drh Exp $
**
** This file contains an example implementation of an asynchronous IO 
** backend for SQLite.
**
** WHAT IS ASYNCHRONOUS I/O?
**
** With asynchronous I/O, write requests are handled by a separate thread
................................................................................
    }else{
      rc = getFileLock(pLock);
    }
  }

  return rc;
}




















/*
** Open a file.
*/
static int asyncOpen(
  sqlite3_vfs *pAsyncVfs,
  const char *zName,
................................................................................
  AsyncFile *p = (AsyncFile *)pFile;
  int nName = 0;
  int rc = SQLITE_OK;
  int nByte;
  AsyncFileData *pData;
  AsyncLock *pLock = 0;
  char *z;
  int isExclusive = (flags&SQLITE_OPEN_EXCLUSIVE);

  /* If zName is NULL, then the upper layer is requesting an anonymous file */
  if( zName ){
    nName = strlen(zName)+1;
  }

  nByte = (
................................................................................
  if( zName ){
    z += pVfs->szOsFile;
    pData->zName = z;
    pData->nName = nName;
    memcpy(pData->zName, zName, nName);
  }

  if( !isExclusive ){

    rc = pVfs->xOpen(pVfs, zName, pData->pBaseRead, flags, pOutFlags);
    if( rc==SQLITE_OK && ((*pOutFlags)&SQLITE_OPEN_READWRITE) ){
      rc = pVfs->xOpen(pVfs, zName, pData->pBaseWrite, flags, 0);
    }



  }

  pthread_mutex_lock(&async.lockMutex);

  if( zName && rc==SQLITE_OK ){
    pLock = findLock(pData->zName, pData->nName);
    if( !pLock ){
................................................................................
  pthread_mutex_unlock(&async.lockMutex);

  if( rc==SQLITE_OK ){
    incrOpenFileCount();
    pData->pLock = pLock;
  }

  if( rc==SQLITE_OK && isExclusive ){
    rc = addNewAsyncWrite(pData, ASYNC_OPENEXCLUSIVE, (sqlite3_int64)flags,0,0);
    if( rc==SQLITE_OK ){
      if( pOutFlags ) *pOutFlags = flags;
    }else{
      pthread_mutex_lock(&async.lockMutex);
      unlinkAsyncFile(pData);
      pthread_mutex_unlock(&async.lockMutex);

**
**    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: test_async.c,v 1.53 2009/03/27 09:10:12 danielk1977 Exp $
**
** This file contains an example implementation of an asynchronous IO 
** backend for SQLite.
**
** WHAT IS ASYNCHRONOUS I/O?
**
** With asynchronous I/O, write requests are handled by a separate thread
................................................................................
    }else{
      rc = getFileLock(pLock);
    }
  }

  return rc;
}

/*
** The parameter passed to this function is a copy of a 'flags' parameter
** passed to this modules xOpen() method. This function returns true
** if the file should be opened asynchronously, or false if it should
** be opened immediately.
**
** If the file is to be opened asynchronously, then asyncOpen() will add
** an entry to the event queue and the file will not actually be opened
** until the event is processed. Otherwise, the file is opened directly
** by the caller.
*/
static int doAsynchronousOpen(int flags){
  return (flags&SQLITE_OPEN_CREATE) && (
      (flags&SQLITE_OPEN_MAIN_JOURNAL) ||
      (flags&SQLITE_OPEN_TEMP_JOURNAL) ||
      (flags&SQLITE_OPEN_DELETEONCLOSE)
  );
}

/*
** Open a file.
*/
static int asyncOpen(
  sqlite3_vfs *pAsyncVfs,
  const char *zName,
................................................................................
  AsyncFile *p = (AsyncFile *)pFile;
  int nName = 0;
  int rc = SQLITE_OK;
  int nByte;
  AsyncFileData *pData;
  AsyncLock *pLock = 0;
  char *z;
  int isAsyncOpen = doAsynchronousOpen(flags);

  /* If zName is NULL, then the upper layer is requesting an anonymous file */
  if( zName ){
    nName = strlen(zName)+1;
  }

  nByte = (
................................................................................
  if( zName ){
    z += pVfs->szOsFile;
    pData->zName = z;
    pData->nName = nName;
    memcpy(pData->zName, zName, nName);
  }

  if( !isAsyncOpen ){
    int flagsout;
    rc = pVfs->xOpen(pVfs, zName, pData->pBaseRead, flags, &flagsout);
    if( rc==SQLITE_OK && (flagsout&SQLITE_OPEN_READWRITE) ){
      rc = pVfs->xOpen(pVfs, zName, pData->pBaseWrite, flags, 0);
    }
    if( pOutFlags ){
      *pOutFlags = flagsout;
    }
  }

  pthread_mutex_lock(&async.lockMutex);

  if( zName && rc==SQLITE_OK ){
    pLock = findLock(pData->zName, pData->nName);
    if( !pLock ){
................................................................................
  pthread_mutex_unlock(&async.lockMutex);

  if( rc==SQLITE_OK ){
    incrOpenFileCount();
    pData->pLock = pLock;
  }

  if( rc==SQLITE_OK && isAsyncOpen ){
    rc = addNewAsyncWrite(pData, ASYNC_OPENEXCLUSIVE, (sqlite3_int64)flags,0,0);
    if( rc==SQLITE_OK ){
      if( pOutFlags ) *pOutFlags = flags;
    }else{
      pthread_mutex_lock(&async.lockMutex);
      unlinkAsyncFile(pData);
      pthread_mutex_unlock(&async.lockMutex);

#    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.  The
# focus of this script is database locks.
#
# $Id: trans.test,v 1.39 2008/12/22 10:58:46 danielk1977 Exp $


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

# Create several tables to work with.
#
................................................................................
# Arrange for another process to begin modifying the database but abort
# and die in the middle of the modification.  Then have this process read
# the database.  This process should detect the journal file and roll it
# back.  Verify that this happens correctly.
#
set fd [open test.tcl w]
puts $fd {

  sqlite3 db test.db
  db eval {
    PRAGMA default_cache_size=20;
    BEGIN;
    CREATE TABLE t3 AS SELECT * FROM t2;
    DELETE FROM t2;
  }
................................................................................
} $checksum
do_test trans-8.2 {
  execsql {SELECT md5sum(type,name,tbl_name,rootpage,sql) FROM sqlite_master}
} $checksum2
integrity_check trans-8.3
set fd [open test.tcl w]
puts $fd {

  sqlite3 db test.db
  db eval {
    PRAGMA journal_mode=persist;
    PRAGMA default_cache_size=20;
    BEGIN;
    CREATE TABLE t3 AS SELECT * FROM t2;
    DELETE FROM t2;
................................................................................
  catch {exec [info nameofexec] test.tcl}
  execsql {SELECT md5sum(x,y,z) FROM t2}
} $checksum
do_test trans-8.5 {
  execsql {SELECT md5sum(type,name,tbl_name,rootpage,sql) FROM sqlite_master}
} $checksum2
integrity_check trans-8.6


# In the following sequence of tests, compute the MD5 sum of the content
# of a table, make lots of modifications to that table, then do a rollback.
# Verify that after the rollback, the MD5 checksum is unchanged.
#
do_test trans-9.1 {
  execsql {

#    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.  The
# focus of this script is database locks.
#
# $Id: trans.test,v 1.40 2009/03/27 09:10:12 danielk1977 Exp $


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

# Create several tables to work with.
#
................................................................................
# Arrange for another process to begin modifying the database but abort
# and die in the middle of the modification.  Then have this process read
# the database.  This process should detect the journal file and roll it
# back.  Verify that this happens correctly.
#
set fd [open test.tcl w]
puts $fd {
  sqlite3_test_control_pending_byte 0x0010000
  sqlite3 db test.db
  db eval {
    PRAGMA default_cache_size=20;
    BEGIN;
    CREATE TABLE t3 AS SELECT * FROM t2;
    DELETE FROM t2;
  }
................................................................................
} $checksum
do_test trans-8.2 {
  execsql {SELECT md5sum(type,name,tbl_name,rootpage,sql) FROM sqlite_master}
} $checksum2
integrity_check trans-8.3
set fd [open test.tcl w]
puts $fd {
  sqlite3_test_control_pending_byte 0x0010000
  sqlite3 db test.db
  db eval {
    PRAGMA journal_mode=persist;
    PRAGMA default_cache_size=20;
    BEGIN;
    CREATE TABLE t3 AS SELECT * FROM t2;
    DELETE FROM t2;
................................................................................
  catch {exec [info nameofexec] test.tcl}
  execsql {SELECT md5sum(x,y,z) FROM t2}
} $checksum
do_test trans-8.5 {
  execsql {SELECT md5sum(type,name,tbl_name,rootpage,sql) FROM sqlite_master}
} $checksum2
integrity_check trans-8.6


# In the following sequence of tests, compute the MD5 sum of the content
# of a table, make lots of modifications to that table, then do a rollback.
# Verify that after the rollback, the MD5 checksum is unchanged.
#
do_test trans-9.1 {
  execsql {