1 // Copyright (c) 2012 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/system_monitor/system_monitor.h" 6 7 #include <utility> 8 9 #include "base/logging.h" 10 #include "base/message_loop/message_loop.h" 11 #include "base/time/time.h" 12 13 namespace base { 14 15 static SystemMonitor* g_system_monitor = NULL; 16 17 SystemMonitor::SystemMonitor() 18 : devices_changed_observer_list_( 19 new ObserverListThreadSafe<DevicesChangedObserver>()) { 20 DCHECK(!g_system_monitor); 21 g_system_monitor = this; 22 } 23 24 SystemMonitor::~SystemMonitor() { 25 DCHECK_EQ(this, g_system_monitor); 26 g_system_monitor = NULL; 27 } 28 29 // static 30 SystemMonitor* SystemMonitor::Get() { 31 return g_system_monitor; 32 } 33 34 void SystemMonitor::ProcessDevicesChanged(DeviceType device_type) { 35 NotifyDevicesChanged(device_type); 36 } 37 38 void SystemMonitor::AddDevicesChangedObserver(DevicesChangedObserver* obs) { 39 devices_changed_observer_list_->AddObserver(obs); 40 } 41 42 void SystemMonitor::RemoveDevicesChangedObserver(DevicesChangedObserver* obs) { 43 devices_changed_observer_list_->RemoveObserver(obs); 44 } 45 46 void SystemMonitor::NotifyDevicesChanged(DeviceType device_type) { 47 DVLOG(1) << "DevicesChanged with device type " << device_type; 48 devices_changed_observer_list_->Notify( 49 &DevicesChangedObserver::OnDevicesChanged, device_type); 50 } 51 52 } // namespace base 53