content/browser/background_sync/background_sync_power_observer.cc

   1 // Copyright 2015 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 #include "content/browser/background_sync/background_sync_power_observer.h"
   6
   7 #include "base/power_monitor/power_monitor.h"
   8 #include "base/thread_task_runner_handle.h"
   9
  10 namespace content {
  11
  12 BackgroundSyncPowerObserver::BackgroundSyncPowerObserver(
  13     const base::Closure& power_callback)
  14     : observing_power_monitor_(false),
  15       on_battery_(true),
  16       power_changed_callback_(power_callback) {
  17   base::PowerMonitor* power_monitor = base::PowerMonitor::Get();
  18   if (power_monitor) {
  19     observing_power_monitor_ = true;
  20     on_battery_ = power_monitor->IsOnBatteryPower();
  21     power_monitor->AddObserver(this);
  22   }
  23 }
  24
  25 BackgroundSyncPowerObserver::~BackgroundSyncPowerObserver() {
  26   base::PowerMonitor* power_monitor = base::PowerMonitor::Get();
  27
  28   if (power_monitor)
  29     power_monitor->RemoveObserver(this);
  30 }
  31
  32 bool BackgroundSyncPowerObserver::PowerSufficient(
  33     SyncPowerState power_state) const {
  34   DCHECK(observing_power_monitor_);
  35   DCHECK(base::PowerMonitor::Get());
  36
  37   switch (power_state) {
  38     case POWER_STATE_AUTO:
  39       // TODO(jkarlin): Also check for device status, such as power saving mode
  40       // or user preferences. crbug.com/482088.
  41       return true;
  42     case POWER_STATE_AVOID_DRAINING:
  43       return !on_battery_;
  44   }
  45
  46   NOTREACHED();
  47   return false;
  48 }
  49
  50 void BackgroundSyncPowerObserver::OnPowerStateChange(bool on_battery_power) {
  51   DCHECK(observing_power_monitor_);
  52   DCHECK(base::PowerMonitor::Get());
  53
  54   if (on_battery_ == on_battery_power)
  55     return;
  56
  57   on_battery_ = on_battery_power;
  58   base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
  59                                                 power_changed_callback_);
  60 }
  61
  62 }  // namespace content