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 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
29#pragma once
30
31#include <memory>
32#include <wtf/HashSet.h>
33#include <wtf/MessageQueue.h>
34#include <wtf/RefPtr.h>
35#include <wtf/Threading.h>
36
37namespace WebCore {
38
39class Database;
40class DatabaseTask;
41class DatabaseTaskSynchronizer;
42class Document;
43class SQLTransactionCoordinator;
44
45class DatabaseThread : public ThreadSafeRefCounted<DatabaseThread> {
46public:
47 static Ref<DatabaseThread> create() { return adoptRef(*new DatabaseThread); }
48 ~DatabaseThread();
49
50 void start();
51 void requestTermination(DatabaseTaskSynchronizer* cleanupSync);
52 bool terminationRequested(DatabaseTaskSynchronizer* = nullptr) const;
53
54 void scheduleTask(std::unique_ptr<DatabaseTask>&&);
55 void scheduleImmediateTask(std::unique_ptr<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.
56 void unscheduleDatabaseTasks(Database&);
57 bool hasPendingDatabaseActivity() const;
58
59 void recordDatabaseOpen(Database&);
60 void recordDatabaseClosed(Database&);
61 Thread* getThread() { return m_thread.get(); }
62
63 SQLTransactionCoordinator* transactionCoordinator() { return m_transactionCoordinator.get(); }
64
65private:
66 DatabaseThread();
67
68 void databaseThread();
69
70 Lock m_threadCreationMutex;
71 RefPtr<Thread> m_thread;
72 RefPtr<DatabaseThread> m_selfRef;
73
74 MessageQueue<DatabaseTask> m_queue;
75
76 // This set keeps track of the open databases that have been used on this thread.
77 using DatabaseSet = HashSet<RefPtr<Database>>;
78 mutable Lock m_openDatabaseSetMutex;
79 DatabaseSet m_openDatabaseSet;
80
81 std::unique_ptr<SQLTransactionCoordinator> m_transactionCoordinator;
82 DatabaseTaskSynchronizer* m_cleanupSync { nullptr };
83};
84
85} // namespace WebCore
86