content/browser/power_profiler/power_profiler_service.h

   1 // Copyright 2014 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 CONTENT_BROWSER_POWER_PROFILER_POWER_PROFILER_SERVICE_H_
   6 #define CONTENT_BROWSER_POWER_PROFILER_POWER_PROFILER_SERVICE_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/singleton.h"
  10 #include "base/observer_list.h"
  11 #include "base/task_runner.h"
  12 #include "base/timer/timer.h"
  13 #include "content/browser/power_profiler/power_data_provider.h"
  14 #include "content/browser/power_profiler/power_profiler_observer.h"
  15 #include "content/common/content_export.h"
  16
  17 namespace content {
  18
  19 // A class used to query power information and notify the observers.
  20 class CONTENT_EXPORT PowerProfilerService {
  21  public:
  22   static PowerProfilerService* GetInstance();
  23
  24   // Add and remove an observer.
  25   void AddObserver(PowerProfilerObserver* observer);
  26   void RemoveObserver(PowerProfilerObserver* observer);
  27
  28   bool IsAvailable() const;
  29   std::string GetAccuracyLevel() const;
  30
  31   virtual ~PowerProfilerService();
  32
  33  private:
  34   enum Status {
  35     UNINITIALIZED,
  36     INITIALIZED,  // Initialized, profiling has not started.
  37     PROFILING
  38   };
  39
  40   friend struct DefaultSingletonTraits<PowerProfilerService>;
  41   friend class PowerProfilerServiceTest;
  42
  43   PowerProfilerService();
  44
  45   PowerProfilerService(scoped_ptr<PowerDataProvider> provider,
  46                        scoped_refptr<base::TaskRunner> task_runner,
  47                        const base::TimeDelta& sample_period);
  48
  49   void Start();
  50   void Stop();
  51
  52   // Query power data from PowerDataProvider, executes on the WorkerPool thread.
  53   void QueryDataOnTaskRunner();
  54
  55   // Initiate the query on the UI thread, the task is delegated to
  56   // QueryDataOnTaskRunner.
  57   void QueryData();
  58
  59   // Executes on the UI thread.
  60   void Notify(const PowerEventVector&);
  61
  62   base::RepeatingTimer<PowerProfilerService> query_power_timer_;
  63   scoped_refptr<base::TaskRunner> task_runner_;
  64
  65   Status status_;
  66
  67   // Sampling period of power data measurement.
  68   base::TimeDelta sample_period_;
  69   base::ObserverList<PowerProfilerObserver> observers_;
  70
  71   scoped_ptr<PowerDataProvider> data_provider_;
  72
  73   DISALLOW_COPY_AND_ASSIGN(PowerProfilerService);
  74 };
  75
  76 }  // namespace content
  77
  78 #endif  // CONTENT_BROWSER_POWER_PROFILER_POWER_PROFILER_SERVICE_H_