| // Copyright (c) 2011 The Chromium Authors. All rights reserved. | 
 | // Use of this source code is governed by a BSD-style license that can be | 
 | // found in the LICENSE file. | 
 |  | 
 | #ifndef BASE_TIMER_HI_RES_TIMER_MANAGER_H_ | 
 | #define BASE_TIMER_HI_RES_TIMER_MANAGER_H_ | 
 |  | 
 | #include "base/base_export.h" | 
 | #include "base/macros.h" | 
 | #include "base/memory/ref_counted.h" | 
 | #include "base/timer/timer.h" | 
 | #include "build_config.h" | 
 |  | 
 | namespace base { | 
 |  | 
 | // Ensures that the Windows high resolution timer is only used | 
 | // when not running on battery power. | 
 | class BASE_EXPORT HighResolutionTimerManager { | 
 |  public: | 
 |   HighResolutionTimerManager(); | 
 |   ~HighResolutionTimerManager(); | 
 |  | 
 |   // Returns true if the hi resolution clock could be used right now. | 
 |   bool hi_res_clock_available() const { return hi_res_clock_available_; } | 
 |  | 
 |  private: | 
 |   // Enable or disable the faster multimedia timer. | 
 |   void UseHiResClock(bool use); | 
 |  | 
 |   bool hi_res_clock_available_; | 
 |  | 
 | #if defined(OS_WIN) | 
 |   // Timer for polling the high resolution timer usage. | 
 |   base::RepeatingTimer timer_; | 
 | #endif | 
 |  | 
 |   DISALLOW_COPY_AND_ASSIGN(HighResolutionTimerManager); | 
 | }; | 
 |  | 
 | }  // namespace base | 
 |  | 
 | #endif  // BASE_TIMER_HI_RES_TIMER_MANAGER_H_ |