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 "content/browser/system_message_window_win.h"
6
7 #include <dbt.h>
8
9 #include "base/logging.h"
10 #include "base/system_monitor/system_monitor.h"
11 #include "base/win/wrapped_window_proc.h"
12 #include "media/audio/win/core_audio_util_win.h"
13
14 namespace content {
15
16 namespace {
17 const wchar_t kWindowClassName[] = L"Chrome_SystemMessageWindow";
18
19 // A static map from a device category guid to base::SystemMonitor::DeviceType.
20 struct {
21 const GUID device_category;
22 const base::SystemMonitor::DeviceType device_type;
23 } const kDeviceCategoryMap[] = {
24 { KSCATEGORY_AUDIO, base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE },
25 { KSCATEGORY_VIDEO, base::SystemMonitor::DEVTYPE_VIDEO_CAPTURE },
26 };
27 } // namespace
28
29 // Manages the device notification handles for SystemMessageWindowWin.
30 class SystemMessageWindowWin::DeviceNotifications {
31 public:
DeviceNotifications(HWND hwnd)32 explicit DeviceNotifications(HWND hwnd) : notifications_() {
33 Register(hwnd);
34 }
35
~DeviceNotifications()36 ~DeviceNotifications() {
37 Unregister();
38 }
39
Register(HWND hwnd)40 void Register(HWND hwnd) {
41 // Request to receive device notifications. All applications receive basic
42 // notifications via WM_DEVICECHANGE but in order to receive detailed device
43 // arrival and removal messages, we need to register.
44 DEV_BROADCAST_DEVICEINTERFACE filter = {0};
45 filter.dbcc_size = sizeof(filter);
46 filter.dbcc_devicetype = DBT_DEVTYP_DEVICEINTERFACE;
47 bool core_audio_support = media::CoreAudioUtil::IsSupported();
48 for (int i = 0; i < arraysize(kDeviceCategoryMap); ++i) {
49 // If CoreAudio is supported, AudioDeviceListenerWin will
50 // take care of monitoring audio devices.
51 if (core_audio_support &&
52 KSCATEGORY_AUDIO == kDeviceCategoryMap[i].device_category) {
53 continue;
54 }
55
56 filter.dbcc_classguid = kDeviceCategoryMap[i].device_category;
57 DCHECK_EQ(notifications_[i], static_cast<HDEVNOTIFY>(NULL));
58 notifications_[i] = RegisterDeviceNotification(
59 hwnd, &filter, DEVICE_NOTIFY_WINDOW_HANDLE);
60 DPLOG_IF(ERROR, !notifications_[i])
61 << "RegisterDeviceNotification failed";
62 }
63 }
64
Unregister()65 void Unregister() {
66 for (int i = 0; i < arraysize(notifications_); ++i) {
67 if (notifications_[i]) {
68 UnregisterDeviceNotification(notifications_[i]);
69 notifications_[i] = NULL;
70 }
71 }
72 }
73
74 private:
75 HDEVNOTIFY notifications_[arraysize(kDeviceCategoryMap)];
76
77 DISALLOW_IMPLICIT_CONSTRUCTORS(DeviceNotifications);
78 };
79
80
SystemMessageWindowWin()81 SystemMessageWindowWin::SystemMessageWindowWin() {
82 WNDCLASSEX window_class;
83 base::win::InitializeWindowClass(
84 kWindowClassName,
85 &base::win::WrappedWindowProc<SystemMessageWindowWin::WndProcThunk>,
86 0, 0, 0, NULL, NULL, NULL, NULL, NULL,
87 &window_class);
88 instance_ = window_class.hInstance;
89 ATOM clazz = RegisterClassEx(&window_class);
90 DCHECK(clazz);
91
92 window_ = CreateWindow(kWindowClassName,
93 0, 0, 0, 0, 0, 0, 0, 0, instance_, 0);
94 SetWindowLongPtr(window_, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(this));
95 device_notifications_.reset(new DeviceNotifications(window_));
96 }
97
~SystemMessageWindowWin()98 SystemMessageWindowWin::~SystemMessageWindowWin() {
99 if (window_) {
100 DestroyWindow(window_);
101 UnregisterClass(kWindowClassName, instance_);
102 }
103 }
104
OnDeviceChange(UINT event_type,LPARAM data)105 LRESULT SystemMessageWindowWin::OnDeviceChange(UINT event_type, LPARAM data) {
106 base::SystemMonitor* monitor = base::SystemMonitor::Get();
107 base::SystemMonitor::DeviceType device_type =
108 base::SystemMonitor::DEVTYPE_UNKNOWN;
109 switch (event_type) {
110 case DBT_DEVNODES_CHANGED:
111 // For this notification, we're happy with the default DEVTYPE_UNKNOWN.
112 break;
113
114 case DBT_DEVICEREMOVECOMPLETE:
115 case DBT_DEVICEARRIVAL: {
116 // This notification has more details about the specific device that
117 // was added or removed. See if this is a category we're interested
118 // in monitoring and if so report the specific device type. If we don't
119 // find the category in our map, ignore the notification and do not
120 // notify the system monitor.
121 DEV_BROADCAST_DEVICEINTERFACE* device_interface =
122 reinterpret_cast<DEV_BROADCAST_DEVICEINTERFACE*>(data);
123 if (device_interface->dbcc_devicetype != DBT_DEVTYP_DEVICEINTERFACE)
124 return TRUE;
125 for (int i = 0; i < arraysize(kDeviceCategoryMap); ++i) {
126 if (kDeviceCategoryMap[i].device_category ==
127 device_interface->dbcc_classguid) {
128 device_type = kDeviceCategoryMap[i].device_type;
129 break;
130 }
131 }
132
133 // Devices that we do not have a DEVTYPE_ for, get detected via
134 // DBT_DEVNODES_CHANGED, so we avoid sending additional notifications
135 // for those here.
136 if (device_type == base::SystemMonitor::DEVTYPE_UNKNOWN)
137 return TRUE;
138 break;
139 }
140
141 default:
142 return TRUE;
143 }
144
145 monitor->ProcessDevicesChanged(device_type);
146
147 return TRUE;
148 }
149
WndProc(HWND hwnd,UINT message,WPARAM wparam,LPARAM lparam)150 LRESULT CALLBACK SystemMessageWindowWin::WndProc(HWND hwnd, UINT message,
151 WPARAM wparam, LPARAM lparam) {
152 switch (message) {
153 case WM_DEVICECHANGE:
154 return OnDeviceChange(static_cast<UINT>(wparam), lparam);
155 default:
156 break;
157 }
158
159 return ::DefWindowProc(hwnd, message, wparam, lparam);
160 }
161
162 } // namespace content
163