1/*
2 * Copyright (C) 2007 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
29#include "config.h"
30#include "WindowMessageBroadcaster.h"
31
32#include "WindowMessageListener.h"
33
34namespace WebCore {
35
36typedef HashMap<HWND, WindowMessageBroadcaster*> InstanceMap;
37
38static InstanceMap& instancesMap()
39{
40    static InstanceMap instances;
41    return instances;
42}
43
44void WindowMessageBroadcaster::addListener(HWND hwnd, WindowMessageListener* listener)
45{
46    WindowMessageBroadcaster* broadcaster = instancesMap().get(hwnd);
47    if (!broadcaster) {
48        broadcaster = new WindowMessageBroadcaster(hwnd);
49        instancesMap().add(hwnd, broadcaster);
50    }
51
52    broadcaster->addListener(listener);
53}
54
55void WindowMessageBroadcaster::removeListener(HWND hwnd, WindowMessageListener* listener)
56{
57    WindowMessageBroadcaster* broadcaster = instancesMap().get(hwnd);
58    if (!broadcaster)
59        return;
60
61    broadcaster->removeListener(listener);
62}
63
64WindowMessageBroadcaster::WindowMessageBroadcaster(HWND hwnd)
65    : m_subclassedWindow(hwnd)
66    , m_originalWndProc(0)
67{
68    ASSERT_ARG(hwnd, IsWindow(hwnd));
69}
70
71WindowMessageBroadcaster::~WindowMessageBroadcaster()
72{
73}
74
75void WindowMessageBroadcaster::addListener(WindowMessageListener* listener)
76{
77    if (m_listeners.isEmpty()) {
78        ASSERT(!m_originalWndProc);
79#pragma warning(disable: 4244 4312)
80        m_originalWndProc = reinterpret_cast<WNDPROC>(SetWindowLongPtr(m_subclassedWindow, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(SubclassedWndProc)));
81    }
82
83    m_listeners.add(listener);
84}
85
86void WindowMessageBroadcaster::removeListener(WindowMessageListener* listener)
87{
88    ListenerSet::iterator found = m_listeners.find(listener);
89    if (found == m_listeners.end())
90        return;
91
92    m_listeners.remove(found);
93
94    if (m_listeners.isEmpty())
95        destroy();
96}
97
98void WindowMessageBroadcaster::destroy()
99{
100    m_listeners.clear();
101    unsubclassWindow();
102    instancesMap().remove(m_subclassedWindow);
103    delete this;
104}
105
106void WindowMessageBroadcaster::unsubclassWindow()
107{
108    SetWindowLongPtr(m_subclassedWindow, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(m_originalWndProc));
109    m_originalWndProc = 0;
110}
111
112LRESULT CALLBACK WindowMessageBroadcaster::SubclassedWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
113{
114    WindowMessageBroadcaster* broadcaster = instancesMap().get(hwnd);
115    ASSERT(broadcaster);
116
117    ListenerSet::const_iterator end = broadcaster->listeners().end();
118    for (ListenerSet::const_iterator it = broadcaster->listeners().begin(); it != end; ++it)
119        (*it)->windowReceivedMessage(hwnd, message, wParam, lParam);
120
121    WNDPROC originalWndProc = broadcaster->originalWndProc();
122
123    // This will delete broadcaster.
124    if (message == WM_DESTROY)
125        broadcaster->destroy();
126
127    return CallWindowProc(originalWndProc, hwnd, message, wParam, lParam);
128}
129
130} // namespace WebCore
131