1/* 2 * Copyright (C) 2006 Apple Computer, 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 COMPUTER, 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 COMPUTER, 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 Timer_h 27#define Timer_h 28 29#include <wtf/Noncopyable.h> 30#include <wtf/Threading.h> 31#include <wtf/Vector.h> 32 33namespace WebCore { 34 35// Time intervals are all in seconds. 36 37class TimerHeapElement; 38 39class TimerBase { 40 WTF_MAKE_NONCOPYABLE(TimerBase); WTF_MAKE_FAST_ALLOCATED; 41public: 42 TimerBase(); 43 virtual ~TimerBase(); 44 45 void start(double nextFireInterval, double repeatInterval); 46 47 void startRepeating(double repeatInterval) { start(repeatInterval, repeatInterval); } 48 void startOneShot(double interval) { start(interval, 0); } 49 50 void stop(); 51 bool isActive() const; 52 53 double nextFireInterval() const; 54 double nextUnalignedFireInterval() const; 55 double repeatInterval() const { return m_repeatInterval; } 56 57 void augmentFireInterval(double delta) { setNextFireTime(m_nextFireTime + delta); } 58 void augmentRepeatInterval(double delta) { augmentFireInterval(delta); m_repeatInterval += delta; } 59 60 void didChangeAlignmentInterval(); 61 62 static void fireTimersInNestedEventLoop(); 63 64private: 65 virtual void fired() = 0; 66 67 virtual double alignedFireTime(double fireTime) const { return fireTime; } 68 69 void checkConsistency() const; 70 void checkHeapIndex() const; 71 72 void setNextFireTime(double); 73 74 bool inHeap() const { return m_heapIndex != -1; } 75 76 bool hasValidHeapPosition() const; 77 void updateHeapIfNeeded(double oldTime); 78 79 void heapDecreaseKey(); 80 void heapDelete(); 81 void heapDeleteMin(); 82 void heapIncreaseKey(); 83 void heapInsert(); 84 void heapPop(); 85 void heapPopMin(); 86 87 Vector<TimerBase*>& timerHeap() const { ASSERT(m_cachedThreadGlobalTimerHeap); return *m_cachedThreadGlobalTimerHeap; } 88 89 double m_nextFireTime; // 0 if inactive 90 double m_unalignedNextFireTime; // m_nextFireTime not considering alignment interval 91 double m_repeatInterval; // 0 if not repeating 92 int m_heapIndex; // -1 if not in heap 93 unsigned m_heapInsertionOrder; // Used to keep order among equal-fire-time timers 94 Vector<TimerBase*>* m_cachedThreadGlobalTimerHeap; 95 96#ifndef NDEBUG 97 ThreadIdentifier m_thread; 98#endif 99 100 friend class ThreadTimers; 101 friend class TimerHeapLessThanFunction; 102 friend class TimerHeapReference; 103}; 104 105template <typename TimerFiredClass> class Timer : public TimerBase { 106public: 107 typedef void (TimerFiredClass::*TimerFiredFunction)(Timer*); 108 109 Timer(TimerFiredClass* o, TimerFiredFunction f) 110 : m_object(o), m_function(f) { } 111 112private: 113 virtual void fired() { (m_object->*m_function)(this); } 114 115 TimerFiredClass* m_object; 116 TimerFiredFunction m_function; 117}; 118 119inline bool TimerBase::isActive() const 120{ 121 ASSERT(m_thread == currentThread()); 122 return m_nextFireTime; 123} 124 125template <typename TimerFiredClass> class DeferrableOneShotTimer : protected TimerBase { 126public: 127 typedef void (TimerFiredClass::*TimerFiredFunction)(DeferrableOneShotTimer*); 128 129 DeferrableOneShotTimer(TimerFiredClass* o, TimerFiredFunction f, double delay) 130 : m_object(o) 131 , m_function(f) 132 , m_delay(delay) 133 , m_shouldRestartWhenTimerFires(false) 134 { 135 } 136 137 void restart() 138 { 139 // Setting this boolean is much more efficient than calling startOneShot 140 // again, which might result in rescheduling the system timer which 141 // can be quite expensive. 142 143 if (isActive()) { 144 m_shouldRestartWhenTimerFires = true; 145 return; 146 } 147 startOneShot(m_delay); 148 } 149 150 using TimerBase::stop; 151 using TimerBase::isActive; 152private: 153 virtual void fired() 154 { 155 if (m_shouldRestartWhenTimerFires) { 156 m_shouldRestartWhenTimerFires = false; 157 startOneShot(m_delay); 158 return; 159 } 160 161 (m_object->*m_function)(this); 162 } 163 164 TimerFiredClass* m_object; 165 TimerFiredFunction m_function; 166 167 double m_delay; 168 bool m_shouldRestartWhenTimerFires; 169}; 170 171} 172 173#endif 174