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 ScopedEventQueue_h
32#define ScopedEventQueue_h
33
34#include <wtf/NeverDestroyed.h>
35#include <wtf/Noncopyable.h>
36#include <wtf/PassRefPtr.h>
37#include <wtf/RefPtr.h>
38#include <wtf/Vector.h>
39
40namespace WebCore {
41
42class Event;
43class EventQueueScope;
44
45class ScopedEventQueue {
46    WTF_MAKE_NONCOPYABLE(ScopedEventQueue); WTF_MAKE_FAST_ALLOCATED;
47public:
48    static ScopedEventQueue& instance();
49    void enqueueEvent(PassRefPtr<Event>);
50
51private:
52    ScopedEventQueue();
53    ~ScopedEventQueue();
54
55    void dispatchEvent(PassRefPtr<Event>) const;
56    void dispatchAllEvents();
57    void incrementScopingLevel();
58    void decrementScopingLevel();
59
60    Vector<RefPtr<Event>> m_queuedEvents;
61    unsigned m_scopingLevel;
62
63    friend class WTF::NeverDestroyed<WebCore::ScopedEventQueue>;
64    friend class EventQueueScope;
65};
66
67class EventQueueScope {
68    WTF_MAKE_NONCOPYABLE(EventQueueScope);
69public:
70    EventQueueScope() { ScopedEventQueue::instance().incrementScopingLevel(); }
71    ~EventQueueScope() { ScopedEventQueue::instance().decrementScopingLevel(); }
72};
73
74}
75
76#endif // ScopedEventQueue_h
77