--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/storage/DatabaseThread.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2007, 2008 Apple 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.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "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 OR ITS 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 "DatabaseThread.h"
+
+#if ENABLE(DATABASE)
+
+#include "AutodrainedPool.h"
+#include "Database.h"
+#include "DatabaseTask.h"
+#include "Logging.h"
+#include "SQLTransactionClient.h"
+#include "SQLTransactionCoordinator.h"
+
+namespace WebCore {
+
+DatabaseThread::DatabaseThread()
+    : m_threadID(0)
+    , m_transactionClient(new SQLTransactionClient())
+    , m_transactionCoordinator(new SQLTransactionCoordinator())
+    , m_cleanupSync(0)
+{
+    m_selfRef = this;
+}
+
+DatabaseThread::~DatabaseThread()
+{
+    // FIXME: Any cleanup required here?  Since the thread deletes itself after running its detached course, I don't think so.  Lets be sure.
+    ASSERT(terminationRequested());
+}
+
+bool DatabaseThread::start()
+{
+    MutexLocker lock(m_threadCreationMutex);
+
+    if (m_threadID)
+        return true;
+
+    m_threadID = createThread(DatabaseThread::databaseThreadStart, this, "WebCore: Database");
+
+    return m_threadID;
+}
+
+void DatabaseThread::requestTermination(DatabaseTaskSynchronizer *cleanupSync)
+{
+    ASSERT(!m_cleanupSync);
+    m_cleanupSync = cleanupSync;
+    LOG(StorageAPI, "DatabaseThread %p was asked to terminate\n", this);
+    m_queue.kill();
+}
+
+bool DatabaseThread::terminationRequested() const
+{
+    return m_queue.killed();
+}
+
+void* DatabaseThread::databaseThreadStart(void* vDatabaseThread)
+{
+    DatabaseThread* dbThread = static_cast<DatabaseThread*>(vDatabaseThread);
+    return dbThread->databaseThread();
+}
+
+void* DatabaseThread::databaseThread()
+{
+    {
+        // Wait for DatabaseThread::start() to complete.
+        MutexLocker lock(m_threadCreationMutex);
+        LOG(StorageAPI, "Started DatabaseThread %p", this);
+    }
+
+    AutodrainedPool pool;
+    while (OwnPtr<DatabaseTask> task = m_queue.waitForMessage()) {
+        task->performTask();
+        pool.cycle();
+    }
+
+    // Clean up the list of all pending transactions on this database thread
+    m_transactionCoordinator->shutdown();
+
+    LOG(StorageAPI, "About to detach thread %i and clear the ref to DatabaseThread %p, which currently has %i ref(s)", m_threadID, this, refCount());
+
+    // Close the databases that we ran transactions on. This ensures that if any transactions are still open, they are rolled back and we don't leave the database in an
+    // inconsistent or locked state.
+    if (m_openDatabaseSet.size() > 0) {
+        // As the call to close will modify the original set, we must take a copy to iterate over.
+        DatabaseSet openSetCopy;
+        openSetCopy.swap(m_openDatabaseSet);
+        DatabaseSet::iterator end = openSetCopy.end();
+        for (DatabaseSet::iterator it = openSetCopy.begin(); it != end; ++it)
+            (*it)->close();
+    }
+
+    // Detach the thread so its resources are no longer of any concern to anyone else
+    detachThread(m_threadID);
+
+    DatabaseTaskSynchronizer* cleanupSync = m_cleanupSync;
+
+    // Clear the self refptr, possibly resulting in deletion
+    m_selfRef = 0;
+
+    if (cleanupSync) // Someone wanted to know when we were done cleaning up.
+        cleanupSync->taskCompleted();
+
+    return 0;
+}
+
+void DatabaseThread::recordDatabaseOpen(Database* database)
+{
+    ASSERT(currentThread() == m_threadID);
+    ASSERT(database);
+    ASSERT(!m_openDatabaseSet.contains(database));
+    m_openDatabaseSet.add(database);
+}
+
+void DatabaseThread::recordDatabaseClosed(Database* database)
+{
+    ASSERT(currentThread() == m_threadID);
+    ASSERT(database);
+    ASSERT(m_queue.killed() || m_openDatabaseSet.contains(database));
+    m_openDatabaseSet.remove(database);
+}
+
+void DatabaseThread::scheduleTask(PassOwnPtr<DatabaseTask> task)
+{
+    m_queue.append(task);
+}
+
+void DatabaseThread::scheduleImmediateTask(PassOwnPtr<DatabaseTask> task)
+{
+    m_queue.prepend(task);
+}
+
+class SameDatabasePredicate {
+public:
+    SameDatabasePredicate(const Database* database) : m_database(database) { }
+    bool operator()(DatabaseTask* task) const { return task->database() == m_database; }
+private:
+    const Database* m_database;
+};
+
+void DatabaseThread::unscheduleDatabaseTasks(Database* database)
+{
+    // Note that the thread loop is running, so some tasks for the database
+    // may still be executed. This is unavoidable.
+    SameDatabasePredicate predicate(database);
+    m_queue.removeIf(predicate);
+}
+} // namespace WebCore
+#endif