1/*
2 * Copyright (C) 2010 Google 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 are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#ifndef FileThread_h
32#define FileThread_h
33
34#include <functional>
35#include <wtf/MessageQueue.h>
36#include <wtf/PassRefPtr.h>
37#include <wtf/Threading.h>
38
39namespace WebCore {
40
41class FileStream;
42
43class FileThread : public ThreadSafeRefCounted<FileThread> {
44public:
45    static PassRefPtr<FileThread> create()
46    {
47        return adoptRef(new FileThread());
48    }
49
50    ~FileThread();
51
52    bool start();
53    void stop();
54
55    class Task {
56        WTF_MAKE_NONCOPYABLE(Task);
57    public:
58        template<typename T, typename U, typename = typename std::enable_if<!std::is_base_of<Task, U>::value && std::is_convertible<U, std::function<void ()>>::value>::type>
59        Task(T* instance, U method)
60            : m_task(WTF::move(method))
61            , m_instance(instance)
62        {
63        }
64
65        Task(Task&& other)
66            : m_task(WTF::move(other.m_task))
67            , m_instance(other.m_instance)
68        {
69        }
70
71        void performTask()
72        {
73            m_task();
74        }
75        void* instance() const { return m_instance; }
76
77    private:
78        std::function<void ()> m_task;
79        void* m_instance;
80    };
81
82    void postTask(Task);
83
84    void unscheduleTasks(const void* instance);
85
86private:
87    FileThread();
88
89    static void fileThreadStart(void*);
90    void runLoop();
91
92    ThreadIdentifier m_threadID;
93    RefPtr<FileThread> m_selfRef;
94    MessageQueue<Task> m_queue;
95
96    Mutex m_threadCreationMutex;
97};
98
99} // namespace WebCore
100
101#endif // FileThread_h
102