1/*
2 * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
3 * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
15 * its contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
19 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
22 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include "config.h"
31#include "TimeoutChecker.h"
32
33#include "CallFrame.h"
34#include "JSGlobalObject.h"
35
36#if OS(DARWIN)
37#include <mach/mach.h>
38#elif OS(WINDOWS)
39#include <windows.h>
40#else
41#include "CurrentTime.h"
42#endif
43
44using namespace std;
45
46namespace JSC {
47
48// Number of ticks before the first timeout check is done.
49static const int ticksUntilFirstCheck = 1024;
50
51// Default number of milliseconds between each timeout check.
52static const int defaultIntervalBetweenChecks = 1000;
53
54// Returns the time the current thread has spent executing, in milliseconds.
55static inline unsigned getCPUTime()
56{
57#if OS(DARWIN)
58 mach_msg_type_number_t infoCount = THREAD_BASIC_INFO_COUNT;
59 thread_basic_info_data_t info;
60
61 // Get thread information
62 mach_port_t threadPort = mach_thread_self();
63 thread_info(threadPort, THREAD_BASIC_INFO, reinterpret_cast<thread_info_t>(&info), &infoCount);
64 mach_port_deallocate(mach_task_self(), threadPort);
65
66 unsigned time = info.user_time.seconds * 1000 + info.user_time.microseconds / 1000;
67 time += info.system_time.seconds * 1000 + info.system_time.microseconds / 1000;
68
69 return time;
70#elif OS(WINDOWS)
71 union {
72 FILETIME fileTime;
73 unsigned long long fileTimeAsLong;
74 } userTime, kernelTime;
75
76 // GetThreadTimes won't accept NULL arguments so we pass these even though
77 // they're not used.
78 FILETIME creationTime, exitTime;
79
80 GetThreadTimes(GetCurrentThread(), &creationTime, &exitTime, &kernelTime.fileTime, &userTime.fileTime);
81
82 return userTime.fileTimeAsLong / 10000 + kernelTime.fileTimeAsLong / 10000;
83#elif OS(SYMBIAN)
84 RThread current;
85 TTimeIntervalMicroSeconds cpuTime;
86
87 TInt err = current.GetCpuTime(cpuTime);
88 ASSERT_WITH_MESSAGE(err == KErrNone, "GetCpuTime failed with %d", err);
89 return cpuTime.Int64() / 1000;
90#else
91 // FIXME: We should return the time the current thread has spent executing.
92 return currentTime() * 1000;
93#endif
94}
95
96TimeoutChecker::TimeoutChecker()
97 : m_timeoutInterval(0)
98 , m_startCount(0)
99 , m_intervalBetweenChecks(defaultIntervalBetweenChecks)
100{
101 reset();
102}
103
104TimeoutChecker::~TimeoutChecker()
105{
106}
107
108void TimeoutChecker::reset()
109{
110 m_ticksUntilNextCheck = ticksUntilFirstCheck;
111 m_timeAtLastCheck = 0;
112 m_timeExecuting = 0;
113}
114
115void TimeoutChecker::copyTimeoutValues(TimeoutChecker* other)
116{
117 m_timeoutInterval = other->m_timeoutInterval;
118 m_startCount = other->m_startCount;
119 m_intervalBetweenChecks = other->m_intervalBetweenChecks;
120}
121
122bool TimeoutChecker::didTimeOut(ExecState* exec)
123{
124 unsigned currentTime = getCPUTime();
125
126 if (!m_timeAtLastCheck) {
127 // Suspicious amount of looping in a script -- start timing it
128 m_timeAtLastCheck = currentTime;
129 return false;
130 }
131
132 unsigned timeDiff = currentTime - m_timeAtLastCheck;
133
134 if (timeDiff == 0)
135 timeDiff = 1;
136
137 m_timeExecuting += timeDiff;
138 m_timeAtLastCheck = currentTime;
139
140 // Adjust the tick threshold so we get the next checkTimeout call in the
141 // interval specified in intervalBetweenChecks.
142 m_ticksUntilNextCheck = static_cast<unsigned>((static_cast<float>(m_intervalBetweenChecks) / timeDiff) * m_ticksUntilNextCheck);
143 // If the new threshold is 0 reset it to the default threshold. This can happen if the timeDiff is higher than the
144 // preferred script check time interval.
145 if (m_ticksUntilNextCheck == 0)
146 m_ticksUntilNextCheck = ticksUntilFirstCheck;
147
148 if (m_timeoutInterval && m_timeExecuting > m_timeoutInterval) {
149 if (exec->dynamicGlobalObject()->shouldInterruptScript())
150 return true;
151
152 reset();
153 }
154
155 return false;
156}
157
158} // namespace JSC
159

source code of qtscript/src/3rdparty/javascriptcore/JavaScriptCore/runtime/TimeoutChecker.cpp