PluginHalter.cpp revision 643ca7872b450ea4efacab6188849e5aac2ba161 
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
35using namespace std;
36
37namespace WebCore {
38
39PluginHalter::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
47void 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
65void PluginHalter::didStopPlugin(HaltablePlugin* obj)
66{
67    if (!m_client->enabled())
68        return;
69
70    m_plugins.remove(obj);
71}
72
73void 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
106void 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