76 lines
2.5 KiB
C++
76 lines
2.5 KiB
C++
// Copyright (c) 2012 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_SYSTEM_SYSTEM_MONITOR_H_
|
|
#define BASE_SYSTEM_SYSTEM_MONITOR_H_
|
|
|
|
#include "base/base_export.h"
|
|
#include "base/macros.h"
|
|
#include "base/memory/ref_counted.h"
|
|
#include "base/observer_list_threadsafe.h"
|
|
#include "build/build_config.h"
|
|
|
|
namespace base {
|
|
|
|
// Class for monitoring various system-related subsystems
|
|
// such as power management, network status, etc.
|
|
// TODO(mbelshe): Add support beyond just power management.
|
|
class BASE_EXPORT SystemMonitor {
|
|
public:
|
|
// Type of devices whose change need to be monitored, such as add/remove.
|
|
enum DeviceType {
|
|
DEVTYPE_AUDIO, // Audio device, e.g., microphone.
|
|
DEVTYPE_VIDEO_CAPTURE, // Video capture device, e.g., webcam.
|
|
DEVTYPE_UNKNOWN, // Other devices.
|
|
};
|
|
|
|
// Create SystemMonitor. Only one SystemMonitor instance per application
|
|
// is allowed.
|
|
SystemMonitor();
|
|
~SystemMonitor();
|
|
|
|
// Get the application-wide SystemMonitor (if not present, returns NULL).
|
|
static SystemMonitor* Get();
|
|
|
|
class BASE_EXPORT DevicesChangedObserver {
|
|
public:
|
|
// Notification that the devices connected to the system have changed.
|
|
// This is only implemented on Windows currently.
|
|
virtual void OnDevicesChanged(DeviceType device_type) {}
|
|
|
|
protected:
|
|
virtual ~DevicesChangedObserver() = default;
|
|
};
|
|
|
|
// Add a new observer.
|
|
// Can be called from any thread.
|
|
// Must not be called from within a notification callback.
|
|
void AddDevicesChangedObserver(DevicesChangedObserver* obs);
|
|
|
|
// Remove an existing observer.
|
|
// Can be called from any thread.
|
|
// Must not be called from within a notification callback.
|
|
void RemoveDevicesChangedObserver(DevicesChangedObserver* obs);
|
|
|
|
// The ProcessFoo() style methods are a broken pattern and should not
|
|
// be copied. Any significant addition to this class is blocked on
|
|
// refactoring to improve the state of affairs. See http://crbug.com/149059
|
|
|
|
// Cross-platform handling of a device change event.
|
|
void ProcessDevicesChanged(DeviceType device_type);
|
|
|
|
private:
|
|
// Functions to trigger notifications.
|
|
void NotifyDevicesChanged(DeviceType device_type);
|
|
|
|
scoped_refptr<ObserverListThreadSafe<DevicesChangedObserver>>
|
|
devices_changed_observer_list_;
|
|
|
|
DISALLOW_COPY_AND_ASSIGN(SystemMonitor);
|
|
};
|
|
|
|
} // namespace base
|
|
|
|
#endif // BASE_SYSTEM_SYSTEM_MONITOR_H_
|