Implement timers by posting delayed tasks

Source/platform/Timer.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef Timer_h
 #define Timer_h
 
 #include "platform/PlatformExport.h"
 #include "platform/heap/Handle.h"
+#include "platform/scheduler/CancellableTaskFactory.h"
 #include "public/platform/WebTraceLocation.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/Threading.h"
 #include "wtf/Vector.h"
 
 namespace blink {
 
 // Time intervals are all in seconds.
 
 class PLATFORM_EXPORT TimerBase {
@@ skipping 15 matching lines @@
 
     void stop();
     bool isActive() const;
     const WebTraceLocation& location() const { return m_location; }
 
     double nextFireInterval() const;
     double nextUnalignedFireInterval() const;
     double repeatInterval() const { return m_repeatInterval; }
 
     void augmentRepeatInterval(double delta) {
-        setNextFireTime(m_nextFireTime + delta);
+        double now = monotonicallyIncreasingTime();
+        setNextFireTime(now, m_nextFireTime - now + delta);
         m_repeatInterval += delta;
     }
 
-    void didChangeAlignmentInterval();
+    void didChangeAlignmentInterval(double now);
 
 private:
     virtual void fired() = 0;
 
     virtual double alignedFireTime(double fireTime) const { return fireTime; }
 
-    void checkConsistency() const;
-    void checkHeapIndex() const;
+    void setNextFireTime(double now, double delay);
 
-    void setNextFireTime(double);
-
-    bool inHeap() const { return m_heapIndex != -1; }
-
-    bool hasValidHeapPosition() const;
-    void updateHeapIfNeeded(double oldTime);
-
-    void heapDecreaseKey();
-    void heapDelete();
-    void heapDeleteMin();
-    void heapIncreaseKey();
-    void heapInsert();
-    void heapPop();
-    void heapPopMin();
-
-    Vector<TimerBase*>& timerHeap() const { ASSERT(m_cachedThreadGlobalTimerHeap); return *m_cachedThreadGlobalTimerHeap; }
+    void run();
 
     double m_nextFireTime; // 0 if inactive
     double m_unalignedNextFireTime; // m_nextFireTime not considering alignment interval
     double m_repeatInterval; // 0 if not repeating
-    int m_heapIndex; // -1 if not in heap
-    unsigned m_heapInsertionOrder; // Used to keep order among equal-fire-time timers
-    Vector<TimerBase*>* m_cachedThreadGlobalTimerHeap;
     WebTraceLocation m_location;
+    CancellableTaskFactory m_cancellableTaskFactory;
+    WebScheduler* m_webScheduler; // Not owned.
 
 #if ENABLE(ASSERT)
     ThreadIdentifier m_thread;
 #endif
 
     friend class ThreadTimers;
     friend class TimerHeapLessThanFunction;
     friend class TimerHeapReference;
 };
 
@@ skipping 36 matching lines @@
     // This raw pointer is safe as long as Timer<X> is held by the X itself (That's the case
     // in the current code base).
     GC_PLUGIN_IGNORE("363031")
     TimerFiredClass* m_object;
     TimerFiredFunction m_function;
 };
 
 inline bool TimerBase::isActive() const
 {
     ASSERT(m_thread == currentThread());
-    return m_nextFireTime;
+    return m_cancellableTaskFactory.isPending();
 }
 
 }
 
 #endif