1 /*
2 * Copyright (C) 2009 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 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "config.h"
27
28 #include "PluginHalter.h"
29
30 #include "HaltablePlugin.h"
31 #include "PlatformString.h"
32 #include <wtf/CurrentTime.h>
33 #include <wtf/Vector.h>
34
35 using namespace std;
36
37 namespace WebCore {
38
PluginHalter(PluginHalterClient * client)39 PluginHalter::PluginHalter(PluginHalterClient* client)
40 : m_client(client)
41 , m_timer(this, &PluginHalter::timerFired)
42 , m_pluginAllowedRunTime(numeric_limits<unsigned>::max())
43 {
44 ASSERT_ARG(client, client);
45 }
46
didStartPlugin(HaltablePlugin * obj)47 void PluginHalter::didStartPlugin(HaltablePlugin* obj)
48 {
49 ASSERT_ARG(obj, obj);
50 ASSERT_ARG(obj, !m_plugins.contains(obj));
51
52 if (!m_client->enabled())
53 return;
54
55 double currentTime = WTF::currentTime();
56
57 m_plugins.add(obj, currentTime);
58
59 if (m_plugins.size() == 1)
60 m_oldestStartTime = currentTime;
61
62 startTimerIfNecessary();
63 }
64
didStopPlugin(HaltablePlugin * obj)65 void PluginHalter::didStopPlugin(HaltablePlugin* obj)
66 {
67 if (!m_client->enabled())
68 return;
69
70 m_plugins.remove(obj);
71 }
72
timerFired(Timer<PluginHalter> *)73 void PluginHalter::timerFired(Timer<PluginHalter>*)
74 {
75 if (m_plugins.isEmpty())
76 return;
77
78 Vector<HaltablePlugin*> plugins;
79 copyKeysToVector(m_plugins, plugins);
80
81 // Plug-ins older than this are candidates to be halted.
82 double pluginCutOffTime = WTF::currentTime() - m_pluginAllowedRunTime;
83
84 m_oldestStartTime = numeric_limits<double>::max();
85
86 for (size_t i = 0; i < plugins.size(); ++i) {
87 double thisStartTime = m_plugins.get(plugins[i]);
88 if (thisStartTime > pluginCutOffTime) {
89 // This plug-in is too young to be halted. We find the oldest
90 // plug-in that is not old enough to be halted and use it to set
91 // the timer's next fire time.
92 if (thisStartTime < m_oldestStartTime)
93 m_oldestStartTime = thisStartTime;
94 continue;
95 }
96
97 if (m_client->shouldHaltPlugin(plugins[i]->node(), plugins[i]->isWindowed(), plugins[i]->pluginName()))
98 plugins[i]->halt();
99
100 m_plugins.remove(plugins[i]);
101 }
102
103 startTimerIfNecessary();
104 }
105
startTimerIfNecessary()106 void PluginHalter::startTimerIfNecessary()
107 {
108 if (m_timer.isActive())
109 return;
110
111 if (m_plugins.isEmpty())
112 return;
113
114 double nextFireInterval = static_cast<double>(m_pluginAllowedRunTime) - (currentTime() - m_oldestStartTime);
115 m_timer.startOneShot(nextFireInterval < 0 ? 0 : nextFireInterval);
116 }
117
118 } // namespace WebCore
119