1 // Copyright 2013 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 // libudev is used for monitoring device changes.
6
7 #include "content/browser/device_monitor_udev.h"
8
9 #include <libudev.h>
10
11 #include <string>
12
13 #include "base/system_monitor/system_monitor.h"
14 #include "content/browser/udev_linux.h"
15 #include "content/public/browser/browser_thread.h"
16
17 namespace {
18
19 struct SubsystemMap {
20 base::SystemMonitor::DeviceType device_type;
21 const char* subsystem;
22 const char* devtype;
23 };
24
25 const char kAudioSubsystem[] = "sound";
26 const char kVideoSubsystem[] = "video4linux";
27
28 // Add more subsystems here for monitoring.
29 const SubsystemMap kSubsystemMap[] = {
30 { base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE, kAudioSubsystem, NULL },
31 { base::SystemMonitor::DEVTYPE_VIDEO_CAPTURE, kVideoSubsystem, NULL },
32 };
33
34 } // namespace
35
36 namespace content {
37
DeviceMonitorLinux()38 DeviceMonitorLinux::DeviceMonitorLinux() {
39 DCHECK(BrowserThread::IsMessageLoopValid(BrowserThread::IO));
40 BrowserThread::PostTask(BrowserThread::IO,
41 FROM_HERE,
42 base::Bind(&DeviceMonitorLinux::Initialize, base::Unretained(this)));
43 }
44
~DeviceMonitorLinux()45 DeviceMonitorLinux::~DeviceMonitorLinux() {
46 }
47
Initialize()48 void DeviceMonitorLinux::Initialize() {
49 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
50
51 // We want to be notified of IO message loop destruction to delete |udev_|.
52 base::MessageLoop::current()->AddDestructionObserver(this);
53
54 std::vector<UdevLinux::UdevMonitorFilter> filters;
55 for (size_t i = 0; i < arraysize(kSubsystemMap); ++i) {
56 filters.push_back(UdevLinux::UdevMonitorFilter(
57 kSubsystemMap[i].subsystem, kSubsystemMap[i].devtype));
58 }
59 udev_.reset(new UdevLinux(filters,
60 base::Bind(&DeviceMonitorLinux::OnDevicesChanged,
61 base::Unretained(this))));
62 }
63
WillDestroyCurrentMessageLoop()64 void DeviceMonitorLinux::WillDestroyCurrentMessageLoop() {
65 // Called on IO thread.
66 udev_.reset();
67 }
68
OnDevicesChanged(udev_device * device)69 void DeviceMonitorLinux::OnDevicesChanged(udev_device* device) {
70 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
71 DCHECK(device);
72
73 base::SystemMonitor::DeviceType device_type =
74 base::SystemMonitor::DEVTYPE_UNKNOWN;
75 std::string subsystem(udev_device_get_subsystem(device));
76 for (size_t i = 0; i < arraysize(kSubsystemMap); ++i) {
77 if (subsystem == kSubsystemMap[i].subsystem) {
78 device_type = kSubsystemMap[i].device_type;
79 break;
80 }
81 }
82 DCHECK_NE(device_type, base::SystemMonitor::DEVTYPE_UNKNOWN);
83
84 base::SystemMonitor::Get()->ProcessDevicesChanged(device_type);
85 }
86
87 } // namespace content
88