third_party/WebKit/Source/platform/Timer.h

   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/heap/Handle.h"
  31 #include "public/platform/WebTraceLocation.h"
  32 #include "wtf/AddressSanitizer.h"
  33 #include "wtf/Noncopyable.h"
  34 #include "wtf/Threading.h"
  35 #include "wtf/Vector.h"
  36
  37 namespace blink {
  38
  39 // Time intervals are all in seconds.
  40
  41 class PLATFORM_EXPORT TimerBase {
  42     WTF_MAKE_NONCOPYABLE(TimerBase);
  43 public:
  44     TimerBase();
  45     virtual ~TimerBase();
  46
  47     void start(double nextFireInterval, double repeatInterval, const WebTraceLocation&);
  48
  49     void startRepeating(double repeatInterval, const WebTraceLocation& caller)
  50     {
  51         start(repeatInterval, repeatInterval, caller);
  52     }
  53     void startOneShot(double interval, const WebTraceLocation& caller)
  54     {
  55         start(interval, 0, caller);
  56     }
  57
  58     void stop();
  59     bool isActive() const;
  60     const WebTraceLocation& location() const { return m_location; }
  61
  62     double nextFireInterval() const;
  63     double nextUnalignedFireInterval() const;
  64     double repeatInterval() const { return m_repeatInterval; }
  65
  66     void augmentRepeatInterval(double delta) {
  67         double now = monotonicallyIncreasingTime();
  68         setNextFireTime(now, m_nextFireTime - now + delta);
  69         m_repeatInterval += delta;
  70     }
  71
  72     void didChangeAlignmentInterval(double now);
  73
  74     struct PLATFORM_EXPORT Comparator {
  75         bool operator()(const TimerBase* a, const TimerBase* b) const;
  76     };
  77
  78 private:
  79     virtual void fired() = 0;
  80
  81     NO_LAZY_SWEEP_SANITIZE_ADDRESS
  82     virtual bool canFire() const { return true; }
  83
  84     virtual double alignedFireTime(double fireTime) const { return fireTime; }
  85
  86     void setNextFireTime(double now, double delay);
  87
  88     void runInternal();
  89
  90     class CancellableTimerTask final : public WebThread::Task {
  91         WTF_MAKE_NONCOPYABLE(CancellableTimerTask);
  92     public:
  93         explicit CancellableTimerTask(TimerBase* timer) : m_timer(timer) { }
  94
  95         ~CancellableTimerTask() override
  96         {
  97             if (m_timer)
  98                 m_timer->m_cancellableTimerTask = nullptr;
  99         }
 100
 101         NO_LAZY_SWEEP_SANITIZE_ADDRESS
 102         void run() override
 103         {
 104             if (m_timer) {
 105                 m_timer->m_cancellableTimerTask = nullptr;
 106                 m_timer->runInternal();
 107                 m_timer = nullptr;
 108             }
 109         }
 110
 111         void cancel()
 112         {
 113             m_timer = nullptr;
 114         }
 115
 116     private:
 117         TimerBase* m_timer; // NOT OWNED
 118     };
 119
 120     double m_nextFireTime; // 0 if inactive
 121     double m_unalignedNextFireTime; // m_nextFireTime not considering alignment interval
 122     double m_repeatInterval; // 0 if not repeating
 123     WebTraceLocation m_location;
 124     CancellableTimerTask* m_cancellableTimerTask; // NOT OWNED
 125     WebScheduler* m_webScheduler; // Not owned.
 126
 127 #if ENABLE(ASSERT)
 128     ThreadIdentifier m_thread;
 129 #endif
 130
 131     friend class ThreadTimers;
 132     friend class TimerHeapLessThanFunction;
 133     friend class TimerHeapReference;
 134 };
 135
 136 template<typename T, bool = IsGarbageCollectedType<T>::value>
 137 class TimerIsObjectAliveTrait {
 138 public:
 139     static bool isHeapObjectAlive(T*) { return true; }
 140 };
 141
 142 template<typename T>
 143 class TimerIsObjectAliveTrait<T, true> {
 144 public:
 145     static bool isHeapObjectAlive(T* objectPointer)
 146     {
 147         return !Heap::willObjectBeLazilySwept(objectPointer);
 148     }
 149 };
 150
 151 template <typename TimerFiredClass>
 152 class Timer : public TimerBase {
 153 public:
 154     typedef void (TimerFiredClass::*TimerFiredFunction)(Timer*);
 155
 156     Timer(TimerFiredClass* o, TimerFiredFunction f)
 157         : m_object(o), m_function(f)
 158     {
 159     }
 160
 161 protected:
 162     void fired() override
 163     {
 164         (m_object->*m_function)(this);
 165     }
 166
 167     NO_LAZY_SWEEP_SANITIZE_ADDRESS
 168     bool canFire() const override
 169     {
 170         // Oilpan: if a timer fires while Oilpan heaps are being lazily
 171         // swept, it is not safe to proceed if the object is about to
 172         // be swept (and this timer will be stopped while doing so.)
 173         return TimerIsObjectAliveTrait<TimerFiredClass>::isHeapObjectAlive(m_object);
 174     }
 175
 176 private:
 177     // FIXME: Oilpan: TimerBase should be moved to the heap and m_object should be traced.
 178     // This raw pointer is safe as long as Timer<X> is held by the X itself (That's the case
 179     // in the current code base).
 180     GC_PLUGIN_IGNORE("363031")
 181     TimerFiredClass* m_object;
 182     TimerFiredFunction m_function;
 183 };
 184
 185 NO_LAZY_SWEEP_SANITIZE_ADDRESS
 186 inline bool TimerBase::isActive() const
 187 {
 188     ASSERT(m_thread == currentThread());
 189     return m_cancellableTimerTask;
 190 }
 191
 192 } // namespace blink
 193
 194 #endif // Timer_h