1/*
2 * Copyright (C) 2007, 2014 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#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    ASSERT(m_originalWndProc);
83
84    m_listeners.add(listener);
85}
86
87void WindowMessageBroadcaster::removeListener(WindowMessageListener* listener)
88{
89    m_listeners.remove(listener);
90    if (m_listeners.isEmpty())
91        destroy();
92}
93
94void WindowMessageBroadcaster::destroy()
95{
96    m_listeners.clear();
97    unsubclassWindow();
98    instancesMap().remove(m_subclassedWindow);
99    delete this;
100}
101
102void WindowMessageBroadcaster::unsubclassWindow()
103{
104    SetWindowLongPtr(m_subclassedWindow, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(m_originalWndProc));
105    m_originalWndProc = 0;
106}
107
108LRESULT CALLBACK WindowMessageBroadcaster::SubclassedWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
109{
110    WindowMessageBroadcaster* broadcaster = instancesMap().get(hwnd);
111    ASSERT(broadcaster);
112    if (!broadcaster)
113        return 0;
114
115    ListenerSet::const_iterator end = broadcaster->listeners().end();
116    for (ListenerSet::const_iterator it = broadcaster->listeners().begin(); it != end; ++it)
117        (*it)->windowReceivedMessage(hwnd, message, wParam, lParam);
118
119    WNDPROC originalWndProc = broadcaster->originalWndProc();
120
121    // This will delete broadcaster.
122    if (message == WM_DESTROY)
123        broadcaster->destroy();
124
125    return CallWindowProc(originalWndProc, hwnd, message, wParam, lParam);
126}
127
128} // namespace WebCore
129