1// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef BASE_TIMER_HI_RES_TIMER_MANAGER_H_ 6#define BASE_TIMER_HI_RES_TIMER_MANAGER_H_ 7 8#include "base/base_export.h" 9#include "base/basictypes.h" 10#include "base/power_monitor/power_observer.h" 11 12namespace base { 13 14// Ensures that the Windows high resolution timer is only used 15// when not running on battery power. 16class BASE_EXPORT HighResolutionTimerManager : public base::PowerObserver { 17 public: 18 HighResolutionTimerManager(); 19 virtual ~HighResolutionTimerManager(); 20 21 // base::PowerObserver method. 22 virtual void OnPowerStateChange(bool on_battery_power) OVERRIDE; 23 24 // Returns true if the hi resolution clock could be used right now. 25 bool hi_res_clock_available() const { return hi_res_clock_available_; } 26 27 private: 28 // Enable or disable the faster multimedia timer. 29 void UseHiResClock(bool use); 30 31 bool hi_res_clock_available_; 32 33 DISALLOW_COPY_AND_ASSIGN(HighResolutionTimerManager); 34}; 35 36} // namespace base 37 38#endif // BASE_TIMER_HI_RES_TIMER_MANAGER_H_ 39