/* | |
* Copyright (C) 2006 Apple Computer, Inc. All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without | |
* modification, are permitted provided that the following conditions | |
* are met: | |
* 1. Redistributions of source code must retain the above copyright | |
* notice, this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright | |
* notice, this list of conditions and the following disclaimer in the | |
* documentation and/or other materials provided with the distribution. | |
* | |
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY | |
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | |
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR | |
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | |
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
*/ | |
#include "config.h" | |
#include "SQLiteTransaction.h" | |
#include "SQLiteDatabase.h" | |
namespace WebCore { | |
SQLiteTransaction::SQLiteTransaction(SQLiteDatabase& db, bool readOnly) | |
: m_db(db) | |
, m_inProgress(false) | |
, m_readOnly(readOnly) | |
{ | |
} | |
SQLiteTransaction::~SQLiteTransaction() | |
{ | |
if (m_inProgress) | |
rollback(); | |
} | |
void SQLiteTransaction::begin() | |
{ | |
if (!m_inProgress) { | |
ASSERT(!m_db.m_transactionInProgress); | |
// Call BEGIN IMMEDIATE for a write transaction to acquire | |
// a RESERVED lock on the DB file. Otherwise, another write | |
// transaction (on another connection) could make changes | |
// to the same DB file before this transaction gets to execute | |
// any statements. If that happens, this transaction will fail. | |
// http://www.sqlite.org/lang_transaction.html | |
// http://www.sqlite.org/lockingv3.html#locking | |
if (m_readOnly) | |
m_inProgress = m_db.executeCommand("BEGIN"); | |
else | |
m_inProgress = m_db.executeCommand("BEGIN IMMEDIATE"); | |
m_db.m_transactionInProgress = m_inProgress; | |
} | |
} | |
void SQLiteTransaction::commit() | |
{ | |
if (m_inProgress) { | |
ASSERT(m_db.m_transactionInProgress); | |
m_inProgress = !m_db.executeCommand("COMMIT"); | |
m_db.m_transactionInProgress = m_inProgress; | |
} | |
} | |
void SQLiteTransaction::rollback() | |
{ | |
// We do not use the 'm_inProgress = m_db.executeCommand("ROLLBACK")' construct here, | |
// because m_inProgress should always be set to false after a ROLLBACK, and | |
// m_db.executeCommand("ROLLBACK") can sometimes harmlessly fail, thus returning | |
// a non-zero/true result (http://www.sqlite.org/lang_transaction.html). | |
if (m_inProgress) { | |
ASSERT(m_db.m_transactionInProgress); | |
m_db.executeCommand("ROLLBACK"); | |
m_inProgress = false; | |
m_db.m_transactionInProgress = false; | |
} | |
} | |
void SQLiteTransaction::stop() | |
{ | |
if (m_inProgress) { | |
m_inProgress = false; | |
m_db.m_transactionInProgress = false; | |
} | |
} | |
bool SQLiteTransaction::wasRolledBackBySqlite() const | |
{ | |
// According to http://www.sqlite.org/c3ref/get_autocommit.html, | |
// the auto-commit flag should be off in the middle of a transaction | |
return m_inProgress && m_db.isAutoCommitOn(); | |
} | |
} // namespace WebCore |