1/*
2 * Copyright (C) 2007, 2008 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 *
8 * 1.  Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright
11 *     notice, this list of conditions and the following disclaimer in the
12 *     documentation and/or other materials provided with the distribution.
13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 *     its contributors may be used to endorse or promote products derived
15 *     from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28#ifndef DatabaseThread_h
29#define DatabaseThread_h
30
31#if ENABLE(SQL_DATABASE)
32
33#include <wtf/Deque.h>
34#include <wtf/HashMap.h>
35#include <wtf/HashSet.h>
36#include <wtf/MessageQueue.h>
37#include <wtf/OwnPtr.h>
38#include <wtf/PassOwnPtr.h>
39#include <wtf/PassRefPtr.h>
40#include <wtf/RefPtr.h>
41#include <wtf/Threading.h>
42
43namespace WebCore {
44
45class DatabaseBackend;
46class DatabaseTask;
47class DatabaseTaskSynchronizer;
48class Document;
49class SQLTransactionClient;
50class SQLTransactionCoordinator;
51
52class DatabaseThread : public ThreadSafeRefCounted<DatabaseThread> {
53public:
54    static PassRefPtr<DatabaseThread> create() { return adoptRef(new DatabaseThread); }
55    ~DatabaseThread();
56
57    bool start();
58    void requestTermination(DatabaseTaskSynchronizer* cleanupSync);
59    bool terminationRequested(DatabaseTaskSynchronizer* taskSynchronizer = 0) const;
60
61    void scheduleTask(PassOwnPtr<DatabaseTask>);
62    void scheduleImmediateTask(PassOwnPtr<DatabaseTask>); // This just adds the task to the front of the queue - the caller needs to be extremely careful not to create deadlocks when waiting for completion.
63    void unscheduleDatabaseTasks(DatabaseBackend*);
64
65    void recordDatabaseOpen(DatabaseBackend*);
66    void recordDatabaseClosed(DatabaseBackend*);
67    ThreadIdentifier getThreadID() { return m_threadID; }
68
69    SQLTransactionClient* transactionClient() { return m_transactionClient.get(); }
70    SQLTransactionCoordinator* transactionCoordinator() { return m_transactionCoordinator.get(); }
71
72private:
73    DatabaseThread();
74
75    static void databaseThreadStart(void*);
76    void databaseThread();
77
78    Mutex m_threadCreationMutex;
79    ThreadIdentifier m_threadID;
80    RefPtr<DatabaseThread> m_selfRef;
81
82    MessageQueue<DatabaseTask> m_queue;
83
84    // This set keeps track of the open databases that have been used on this thread.
85    typedef HashSet<RefPtr<DatabaseBackend> > DatabaseSet;
86    DatabaseSet m_openDatabaseSet;
87
88    OwnPtr<SQLTransactionClient> m_transactionClient;
89    OwnPtr<SQLTransactionCoordinator> m_transactionCoordinator;
90    DatabaseTaskSynchronizer* m_cleanupSync;
91};
92
93} // namespace WebCore
94
95#endif // ENABLE(SQL_DATABASE)
96#endif // DatabaseThread_h
97