1/* 2 * Copyright (C) 2013 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#ifndef Watchdog_h 27#define Watchdog_h 28 29#if OS(DARWIN) 30#include <dispatch/dispatch.h> 31#endif 32 33namespace JSC { 34 35class ExecState; 36class VM; 37 38class Watchdog { 39public: 40 class Scope; 41 42 Watchdog(); 43 ~Watchdog(); 44 45 typedef bool (*ShouldTerminateCallback)(ExecState*, void* data1, void* data2); 46 void setTimeLimit(VM&, double seconds, ShouldTerminateCallback = 0, void* data1 = 0, void* data2 = 0); 47 48 // This version of didFire() will check the elapsed CPU time and call the 49 // callback (if needed) to determine if the watchdog should fire. 50 bool didFire(ExecState*); 51 52 bool isEnabled(); 53 54 // This version of didFire() is a more efficient version for when we want 55 // to know if the watchdog has fired in the past, and not whether it should 56 // fire right now. 57 bool didFire() { return m_didFire; } 58 JS_EXPORT_PRIVATE void fire(); 59 60 void* timerDidFireAddress() { return &m_timerDidFire; } 61 62private: 63 void arm(); 64 void disarm(); 65 void startCountdownIfNeeded(); 66 void startCountdown(double limit); 67 void stopCountdown(); 68 bool isArmed() { return !!m_reentryCount; } 69 70 // Platform specific timer implementation: 71 void initTimer(); 72 void destroyTimer(); 73 void startTimer(double limit); 74 void stopTimer(); 75 76 // m_timerDidFire (above) indicates whether the timer fired. The Watchdog 77 // still needs to check if the allowed CPU time has elapsed. If so, then 78 // the Watchdog fires and m_didFire will be set. 79 // NOTE: m_timerDidFire is only set by the platform specific timer 80 // (probably from another thread) but is only cleared in the script thread. 81 bool m_timerDidFire; 82 bool m_didFire; 83 84 // All time units are in seconds. 85 double m_limit; 86 double m_startTime; 87 double m_elapsedTime; 88 89 int m_reentryCount; 90 bool m_isStopped; 91 92 ShouldTerminateCallback m_callback; 93 void* m_callbackData1; 94 void* m_callbackData2; 95 96#if OS(DARWIN) && !PLATFORM(EFL) && !PLATFORM(GTK) 97 dispatch_queue_t m_queue; 98 dispatch_source_t m_timer; 99#endif 100 101 friend class Watchdog::Scope; 102 friend class LLIntOffsetsExtractor; 103}; 104 105class Watchdog::Scope { 106public: 107 Scope(Watchdog* watchdog) 108 : m_watchdog(watchdog) 109 { 110 if (!watchdog) 111 return; 112 m_watchdog->arm(); 113 } 114 115 ~Scope() 116 { 117 if (!m_watchdog) 118 return; 119 m_watchdog->disarm(); 120 } 121 122private: 123 Watchdog* m_watchdog; 124}; 125 126} // namespace JSC 127 128#endif // Watchdog_h 129