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 "platform/PlatformExport.h" 30 #include "platform/TraceLocation.h" 31 #include "platform/heap/Handle.h" 32 #include "wtf/Noncopyable.h" 33 #include "wtf/Threading.h" 34 #include "wtf/Vector.h" 35 36 namespace WebCore { 37 38 // Time intervals are all in seconds. 39 40 class TimerHeapElement; 41 42 class PLATFORM_EXPORT TimerBase { 43 WTF_MAKE_NONCOPYABLE(TimerBase); WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED; 44 public: 45 TimerBase(); 46 virtual ~TimerBase(); 47 48 void start(double nextFireInterval, double repeatInterval, const TraceLocation&); 49 50 void startRepeating(double repeatInterval, const TraceLocation& caller) 51 { 52 start(repeatInterval, repeatInterval, caller); 53 } 54 void startOneShot(double interval, const TraceLocation& caller) 55 { 56 start(interval, 0, caller); 57 } 58 59 void stop(); 60 bool isActive() const; 61 const TraceLocation& location() const { return m_location; } 62 63 double nextFireInterval() const; 64 double nextUnalignedFireInterval() const; 65 double repeatInterval() const { return m_repeatInterval; } 66 67 void augmentRepeatInterval(double delta) { 68 setNextFireTime(m_nextFireTime + delta); 69 m_repeatInterval += delta; 70 } 71 72 void didChangeAlignmentInterval(); 73 74 static void fireTimersInNestedEventLoop(); 75 76 private: 77 virtual void fired() = 0; 78 79 virtual double alignedFireTime(double fireTime) const { return fireTime; } 80 81 void checkConsistency() const; 82 void checkHeapIndex() const; 83 84 void setNextFireTime(double); 85 86 bool inHeap() const { return m_heapIndex != -1; } 87 88 bool hasValidHeapPosition() const; 89 void updateHeapIfNeeded(double oldTime); 90 91 void heapDecreaseKey(); 92 void heapDelete(); 93 void heapDeleteMin(); 94 void heapIncreaseKey(); 95 void heapInsert(); 96 void heapPop(); 97 void heapPopMin(); 98 99 Vector<TimerBase*>& timerHeap() const { ASSERT(m_cachedThreadGlobalTimerHeap); return *m_cachedThreadGlobalTimerHeap; } 100 101 double m_nextFireTime; // 0 if inactive 102 double m_unalignedNextFireTime; // m_nextFireTime not considering alignment interval 103 double m_repeatInterval; // 0 if not repeating 104 int m_heapIndex; // -1 if not in heap 105 unsigned m_heapInsertionOrder; // Used to keep order among equal-fire-time timers 106 Vector<TimerBase*>* m_cachedThreadGlobalTimerHeap; 107 TraceLocation m_location; 108 109 #ifndef NDEBUG 110 ThreadIdentifier m_thread; 111 #endif 112 113 friend class ThreadTimers; 114 friend class TimerHeapLessThanFunction; 115 friend class TimerHeapReference; 116 }; 117 118 template <typename TimerFiredClass> 119 class Timer FINAL : public TimerBase { 120 public: 121 typedef void (TimerFiredClass::*TimerFiredFunction)(Timer*); 122 123 Timer(TimerFiredClass* o, TimerFiredFunction f) 124 : m_object(o), m_function(f) { } 125 126 private: 127 virtual void fired() OVERRIDE { (m_object->*m_function)(this); } 128 129 // FIXME: oilpan: TimerBase should be moved to the heap and m_object should be traced. 130 // This raw pointer is safe as long as Timer<X> is held by the X itself (That's the case 131 // in the current code base). 132 GC_PLUGIN_IGNORE("363031") 133 TimerFiredClass* m_object; 134 TimerFiredFunction m_function; 135 }; 136 137 inline bool TimerBase::isActive() const 138 { 139 ASSERT(m_thread == currentThread()); 140 return m_nextFireTime; 141 } 142 143 template <typename TimerFiredClass> 144 class DeferrableOneShotTimer FINAL : private TimerBase { 145 public: 146 typedef void (TimerFiredClass::*TimerFiredFunction)(DeferrableOneShotTimer*); 147 148 DeferrableOneShotTimer(TimerFiredClass* o, TimerFiredFunction f, double delay) 149 : m_object(o) 150 , m_function(f) 151 , m_delay(delay) 152 , m_shouldRestartWhenTimerFires(false) 153 { 154 } 155 156 void restart(const TraceLocation& caller) 157 { 158 // Setting this boolean is much more efficient than calling startOneShot 159 // again, which might result in rescheduling the system timer which 160 // can be quite expensive. 161 162 if (isActive()) { 163 m_shouldRestartWhenTimerFires = true; 164 return; 165 } 166 startOneShot(m_delay, caller); 167 } 168 169 using TimerBase::stop; 170 using TimerBase::isActive; 171 172 private: 173 virtual void fired() OVERRIDE 174 { 175 if (m_shouldRestartWhenTimerFires) { 176 m_shouldRestartWhenTimerFires = false; 177 // FIXME: This should not be FROM_HERE. 178 startOneShot(m_delay, FROM_HERE); 179 return; 180 } 181 182 (m_object->*m_function)(this); 183 } 184 185 // FIXME: oilpan: TimerBase should be moved to the heap and m_object should be traced. 186 // This raw pointer is safe as long as Timer<X> is held by the X itself (That's the case 187 // in the current code base). 188 GC_PLUGIN_IGNORE("363031") 189 TimerFiredClass* m_object; 190 TimerFiredFunction m_function; 191 192 double m_delay; 193 bool m_shouldRestartWhenTimerFires; 194 }; 195 196 } 197 198 #endif 199