1/* 2 * Copyright (C) 2013 Apple 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 INC. AND ITS CONTRIBUTORS ``AS IS'' 14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 23 * THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef PageThrottler_h 27#define PageThrottler_h 28 29#include "Timer.h" 30 31#include <wtf/HashSet.h> 32#include <wtf/RefCounted.h> 33 34namespace WebCore { 35 36class Page; 37class PageActivityAssertionToken; 38 39class PageThrottler : public RefCounted<PageThrottler> { 40public: 41 static PassRefPtr<PageThrottler> create(Page* page) 42 { 43 return adoptRef(new PageThrottler(page)); 44 } 45 46 bool shouldThrottleAnimations() const { return m_throttleState != PageNotThrottledState; } 47 bool shouldThrottleTimers() const { return m_throttleState != PageNotThrottledState; } 48 49 void setThrottled(bool); 50 51 void preventThrottling(); 52 void reportInterestingEvent(); 53 void allowThrottling(); 54 void clearPage(); 55 56 ~PageThrottler(); 57 58private: 59 enum PageThrottleState { 60 PageNotThrottledState, 61 PageWaitingToThrottleState, 62 PageThrottledState 63 }; 64 65 friend class PageActivityAssertionToken; 66 void addActivityToken(PageActivityAssertionToken*); 67 void removeActivityToken(PageActivityAssertionToken*); 68 69 PageThrottler(Page*); 70 void startThrottleHysteresisTimer(); 71 void stopThrottleHysteresisTimer(); 72 void throttleHysteresisTimerFired(Timer<PageThrottler>*); 73 74 Page* m_page; 75 76 void throttlePage(); 77 void unthrottlePage(); 78 79 unsigned m_activeThrottleBlockers; 80 PageThrottleState m_throttleState; 81 Timer<PageThrottler> m_throttleHysteresisTimer; 82 HashSet<PageActivityAssertionToken*> m_activityTokens; 83}; 84 85} 86#endif 87