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 #include "config.h"
32 #include "ScopedEventQueue.h"
33 
34 #include "Event.h"
35 #include "EventTarget.h"
36 
37 namespace WebCore {
38 
39 ScopedEventQueue* ScopedEventQueue::s_instance = 0;
40 
ScopedEventQueue()41 ScopedEventQueue::ScopedEventQueue()
42     : m_scopingLevel(0)
43 {
44 }
45 
~ScopedEventQueue()46 ScopedEventQueue::~ScopedEventQueue()
47 {
48     ASSERT(!m_scopingLevel);
49     ASSERT(!m_queuedEvents.size());
50 }
51 
initialize()52 void ScopedEventQueue::initialize()
53 {
54     ASSERT(!s_instance);
55     OwnPtr<ScopedEventQueue> instance = adoptPtr(new ScopedEventQueue);
56     s_instance = instance.leakPtr();
57 }
58 
enqueueEvent(PassRefPtr<Event> event)59 void ScopedEventQueue::enqueueEvent(PassRefPtr<Event> event)
60 {
61     if (m_scopingLevel)
62         m_queuedEvents.append(event);
63     else
64         dispatchEvent(event);
65 }
66 
dispatchAllEvents()67 void ScopedEventQueue::dispatchAllEvents()
68 {
69     Vector<RefPtr<Event> > queuedEvents;
70     queuedEvents.swap(m_queuedEvents);
71 
72     for (size_t i = 0; i < queuedEvents.size(); i++)
73         dispatchEvent(queuedEvents[i].release());
74 }
75 
dispatchEvent(PassRefPtr<Event> event) const76 void ScopedEventQueue::dispatchEvent(PassRefPtr<Event> event) const
77 {
78     RefPtr<EventTarget> eventTarget = event->target();
79     eventTarget->dispatchEvent(event);
80 }
81 
instance()82 ScopedEventQueue* ScopedEventQueue::instance()
83 {
84     if (!s_instance)
85         initialize();
86 
87     return s_instance;
88 }
89 
incrementScopingLevel()90 void ScopedEventQueue::incrementScopingLevel()
91 {
92     m_scopingLevel++;
93 }
94 
decrementScopingLevel()95 void ScopedEventQueue::decrementScopingLevel()
96 {
97     ASSERT(m_scopingLevel);
98     m_scopingLevel--;
99     if (!m_scopingLevel)
100         dispatchAllEvents();
101 }
102 
103 }
104