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#include "base/timer/hi_res_timer_manager.h"
6
7#include "base/power_monitor/power_monitor.h"
8#include "base/time/time.h"
9
10namespace base {
11
12HighResolutionTimerManager::HighResolutionTimerManager()
13    : hi_res_clock_available_(false) {
14  base::PowerMonitor* power_monitor = base::PowerMonitor::Get();
15  DCHECK(power_monitor != NULL);
16  power_monitor->AddObserver(this);
17  UseHiResClock(!power_monitor->IsOnBatteryPower());
18}
19
20HighResolutionTimerManager::~HighResolutionTimerManager() {
21  base::PowerMonitor::Get()->RemoveObserver(this);
22  UseHiResClock(false);
23}
24
25void HighResolutionTimerManager::OnPowerStateChange(bool on_battery_power) {
26  UseHiResClock(!on_battery_power);
27}
28
29void HighResolutionTimerManager::UseHiResClock(bool use) {
30  if (use == hi_res_clock_available_)
31    return;
32  hi_res_clock_available_ = use;
33  base::Time::EnableHighResolutionTimer(use);
34}
35
36}  // namespace base
37