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