1/* 2 * Copyright (C) 2013 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "config.h" 27#include "DatabaseBackend.h" 28 29#if ENABLE(SQL_DATABASE) 30 31#include "ChangeVersionData.h" 32#include "ChangeVersionWrapper.h" 33#include "DatabaseBackendContext.h" 34#include "DatabaseTask.h" 35#include "DatabaseThread.h" 36#include "DatabaseTracker.h" 37#include "Logging.h" 38#include "SQLTransaction.h" 39#include "SQLTransactionBackend.h" 40#include "SQLTransactionClient.h" 41#include "SQLTransactionCoordinator.h" 42 43namespace WebCore { 44 45DatabaseBackend::DatabaseBackend(PassRefPtr<DatabaseBackendContext> databaseContext, const String& name, const String& expectedVersion, const String& displayName, unsigned long estimatedSize) 46 : DatabaseBackendBase(databaseContext, name, expectedVersion, displayName, estimatedSize, DatabaseType::Async) 47 , m_transactionInProgress(false) 48 , m_isTransactionQueueEnabled(true) 49{ 50} 51 52bool DatabaseBackend::openAndVerifyVersion(bool setVersionInNewDatabase, DatabaseError& error, String& errorMessage) 53{ 54 DatabaseTaskSynchronizer synchronizer; 55 if (!databaseContext()->databaseThread() || databaseContext()->databaseThread()->terminationRequested(&synchronizer)) 56 return false; 57 58 bool success = false; 59 OwnPtr<DatabaseOpenTask> task = DatabaseOpenTask::create(this, setVersionInNewDatabase, &synchronizer, error, errorMessage, success); 60 databaseContext()->databaseThread()->scheduleImmediateTask(task.release()); 61 synchronizer.waitForTaskCompletion(); 62 63 return success; 64} 65 66bool DatabaseBackend::performOpenAndVerify(bool setVersionInNewDatabase, DatabaseError& error, String& errorMessage) 67{ 68 if (DatabaseBackendBase::performOpenAndVerify(setVersionInNewDatabase, error, errorMessage)) { 69 if (databaseContext()->databaseThread()) 70 databaseContext()->databaseThread()->recordDatabaseOpen(this); 71 72 return true; 73 } 74 75 return false; 76} 77 78void DatabaseBackend::close() 79{ 80 ASSERT(databaseContext()->databaseThread()); 81 ASSERT(currentThread() == databaseContext()->databaseThread()->getThreadID()); 82 83 { 84 MutexLocker locker(m_transactionInProgressMutex); 85 86 // Clean up transactions that have not been scheduled yet: 87 // Transaction phase 1 cleanup. See comment on "What happens if a 88 // transaction is interrupted?" at the top of SQLTransactionBackend.cpp. 89 RefPtr<SQLTransactionBackend> transaction; 90 while (!m_transactionQueue.isEmpty()) { 91 transaction = m_transactionQueue.takeFirst(); 92 transaction->notifyDatabaseThreadIsShuttingDown(); 93 } 94 95 m_isTransactionQueueEnabled = false; 96 m_transactionInProgress = false; 97 } 98 99 closeDatabase(); 100 101 // DatabaseThread keeps databases alive by referencing them in its 102 // m_openDatabaseSet. DatabaseThread::recordDatabaseClose() will remove 103 // this database from that set (which effectively deref's it). We hold on 104 // to it with a local pointer here for a liitle longer, so that we can 105 // unschedule any DatabaseTasks that refer to it before the database gets 106 // deleted. 107 RefPtr<DatabaseBackend> protect = this; 108 databaseContext()->databaseThread()->recordDatabaseClosed(this); 109 databaseContext()->databaseThread()->unscheduleDatabaseTasks(this); 110} 111 112PassRefPtr<SQLTransactionBackend> DatabaseBackend::runTransaction(PassRefPtr<SQLTransaction> transaction, 113 bool readOnly, const ChangeVersionData* data) 114{ 115 MutexLocker locker(m_transactionInProgressMutex); 116 if (!m_isTransactionQueueEnabled) 117 return 0; 118 119 RefPtr<SQLTransactionWrapper> wrapper; 120 if (data) 121 wrapper = ChangeVersionWrapper::create(data->oldVersion(), data->newVersion()); 122 123 RefPtr<SQLTransactionBackend> transactionBackend = SQLTransactionBackend::create(this, transaction, wrapper, readOnly); 124 m_transactionQueue.append(transactionBackend); 125 if (!m_transactionInProgress) 126 scheduleTransaction(); 127 128 return transactionBackend; 129} 130 131void DatabaseBackend::inProgressTransactionCompleted() 132{ 133 MutexLocker locker(m_transactionInProgressMutex); 134 m_transactionInProgress = false; 135 scheduleTransaction(); 136} 137 138void DatabaseBackend::scheduleTransaction() 139{ 140 ASSERT(!m_transactionInProgressMutex.tryLock()); // Locked by caller. 141 RefPtr<SQLTransactionBackend> transaction; 142 143 if (m_isTransactionQueueEnabled && !m_transactionQueue.isEmpty()) 144 transaction = m_transactionQueue.takeFirst(); 145 146 if (transaction && databaseContext()->databaseThread()) { 147 OwnPtr<DatabaseTransactionTask> task = DatabaseTransactionTask::create(transaction); 148 LOG(StorageAPI, "Scheduling DatabaseTransactionTask %p for transaction %p\n", task.get(), task->transaction()); 149 m_transactionInProgress = true; 150 databaseContext()->databaseThread()->scheduleTask(task.release()); 151 } else 152 m_transactionInProgress = false; 153} 154 155void DatabaseBackend::scheduleTransactionStep(SQLTransactionBackend* transaction) 156{ 157 if (!databaseContext()->databaseThread()) 158 return; 159 160 OwnPtr<DatabaseTransactionTask> task = DatabaseTransactionTask::create(transaction); 161 LOG(StorageAPI, "Scheduling DatabaseTransactionTask %p for the transaction step\n", task.get()); 162 databaseContext()->databaseThread()->scheduleTask(task.release()); 163} 164 165SQLTransactionClient* DatabaseBackend::transactionClient() const 166{ 167 return databaseContext()->databaseThread()->transactionClient(); 168} 169 170SQLTransactionCoordinator* DatabaseBackend::transactionCoordinator() const 171{ 172 return databaseContext()->databaseThread()->transactionCoordinator(); 173} 174 175} // namespace WebCore 176 177#endif // ENABLE(SQL_DATABASE) 178