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
startRepeating(double repeatInterval,const TraceLocation & caller)50 void startRepeating(double repeatInterval, const TraceLocation& caller)
51 {
52 start(repeatInterval, repeatInterval, caller);
53 }
startOneShot(double interval,const TraceLocation & caller)54 void startOneShot(double interval, const TraceLocation& caller)
55 {
56 start(interval, 0, caller);
57 }
58
59 void stop();
60 bool isActive() const;
location()61 const TraceLocation& location() const { return m_location; }
62
63 double nextFireInterval() const;
64 double nextUnalignedFireInterval() const;
repeatInterval()65 double repeatInterval() const { return m_repeatInterval; }
66
augmentRepeatInterval(double delta)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
alignedFireTime(double fireTime)79 virtual double alignedFireTime(double fireTime) const { return fireTime; }
80
81 void checkConsistency() const;
82 void checkHeapIndex() const;
83
84 void setNextFireTime(double);
85
inHeap()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
timerHeap()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
Timer(TimerFiredClass * o,TimerFiredFunction f)123 Timer(TimerFiredClass* o, TimerFiredFunction f)
124 : m_object(o), m_function(f) { }
125
126 private:
fired()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
isActive()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
DeferrableOneShotTimer(TimerFiredClass * o,TimerFiredFunction f,double delay)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
restart(const TraceLocation & caller)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:
fired()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