Add DeviceMonitorLinux in BrowserMainLoop.

The DeviceMonitorLinux detects device change and sends the signal to SystemMonitor.

This patch depends on http://codereview.chromium.org/10836004/

BUG=137799
Review URL: https://chromiumcodereview.appspot.com/10829073

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149266 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/browser_main_loop.cc

@@ -66,6 +66,10 @@
 #include <glib-object.h>
 #endif
 
+#if defined(OS_LINUX)
+#include "content/browser/device_monitor_linux.h"
+#endif
+
 #if defined(OS_CHROMEOS)
 #include <dbus/dbus-glib.h>
 #endif
@@ -615,6 +619,10 @@ void BrowserMainLoop::BrowserThreadsStarted() {
   ImageTransportFactory::Initialize();
 #endif
 
+#if defined(OS_LINUX)
+  device_monitor_linux_.reset(new DeviceMonitorLinux());
+#endif
+
   // RDH needs the IO thread to be created.
   resource_dispatcher_host_.reset(new ResourceDispatcherHostImpl());
 

content/browser/browser_main_loop.h

@@ -44,9 +44,13 @@ namespace content {
 class BrowserMainParts;
 class BrowserShutdownImpl;
 class BrowserThreadImpl;
-struct MainFunctionParams;
 class ResourceDispatcherHostImpl;
 class WebKitThread;
+struct MainFunctionParams;
+
+#if defined(OS_LINUX)
+class DeviceMonitorLinux;
+#endif
 
 // Implements the main browser loop stages called from BrowserMainRunner.
 // See comments in browser_main_parts.h for additional info.
@@ -105,6 +109,8 @@ class BrowserMainLoop {
   scoped_ptr<BrowserOnlineStateObserver> online_state_observer_;
 #if defined(OS_WIN)
   scoped_ptr<SystemMessageWindowWin> system_message_window_;
+#elif defined(OS_LINUX)
+  scoped_ptr<DeviceMonitorLinux> device_monitor_linux_;
 #endif
 
   // Destroy parts_ before main_message_loop_ (required) and before other

content/browser/device_monitor_linux.cc

+// 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.
+
+// libudev is used for monitoring device changes.
+
+#include "content/browser/device_monitor_linux.h"
+
+#include <libudev.h>
+
+#include <string>
+
+#include "base/system_monitor/system_monitor.h"
+#include "content/browser/udev_linux.h"
+#include "content/public/browser/browser_thread.h"
+
+namespace {
+
+struct SubsystemMap {
+  base::SystemMonitor::DeviceType device_type;
+  const char* subsystem;
+  const char* devtype;
+};
+
+const char kAudioSubsystem[] = "sound";
+const char kVideoSubsystem[] = "video4linux";
+
+// Add more subsystems here for monitoring.
+const SubsystemMap kSubsystemMap[] = {
+  { base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE, kAudioSubsystem, NULL },
+  { base::SystemMonitor::DEVTYPE_VIDEO_CAPTURE, kVideoSubsystem, NULL },
+};
+
+}  // namespace
+
+namespace content {
+
+DeviceMonitorLinux::DeviceMonitorLinux() {
+  DCHECK(BrowserThread::IsMessageLoopValid(BrowserThread::IO));
+  BrowserThread::PostTask(BrowserThread::IO,
+      FROM_HERE,
+      base::Bind(&DeviceMonitorLinux::Initialize, base::Unretained(this)));
+}
+
+DeviceMonitorLinux::~DeviceMonitorLinux() {
+}
+
+void DeviceMonitorLinux::Initialize() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  // We want to be notified of IO message loop destruction to delete |udev_|.
+  MessageLoop::current()->AddDestructionObserver(this);
+
+  std::vector<UdevLinux::UdevMonitorFilter> filters;
+  for (size_t i = 0; i < arraysize(kSubsystemMap); ++i) {
+    filters.push_back(content::UdevLinux::UdevMonitorFilter(
+        kSubsystemMap[i].subsystem, kSubsystemMap[i].devtype));
+  }
+  udev_.reset(new UdevLinux(filters,
+      base::Bind(&DeviceMonitorLinux::OnDevicesChanged,
+                 base::Unretained(this))));
+}
+
+void DeviceMonitorLinux::WillDestroyCurrentMessageLoop() {
+  // Called on IO thread.
+  udev_.reset();
+}
+
+void DeviceMonitorLinux::OnDevicesChanged(udev_device* device) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  DCHECK(device);
+
+  base::SystemMonitor::DeviceType device_type =
+      base::SystemMonitor::DEVTYPE_UNKNOWN;
+  std::string subsystem(udev_device_get_subsystem(device));
+  for (size_t i = 0; i < arraysize(kSubsystemMap); ++i) {
+    if (subsystem == kSubsystemMap[i].subsystem) {
+      device_type = kSubsystemMap[i].device_type;
+      break;
+    }
+  }
+  DCHECK_NE(device_type, base::SystemMonitor::DEVTYPE_UNKNOWN);
+
+  base::SystemMonitor::Get()->ProcessDevicesChanged(device_type);
+}
+
+}  // namespace content

content/browser/device_monitor_linux.h

+// 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.
+
+// This class is used to detect device change and notify base::SystemMonitor
+// on Linux.
+
+#ifndef CONTENT_BROWSER_DEVICE_MONITOR_LINUX_H_
+#define CONTENT_BROWSER_DEVICE_MONITOR_LINUX_H_
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/message_loop.h"
+
+extern "C" {
+struct udev_device;
+}
+
+namespace content {
+
+class UdevLinux;
+
+class DeviceMonitorLinux : public MessageLoop::DestructionObserver {
+ public:
+  DeviceMonitorLinux();
+  virtual ~DeviceMonitorLinux();
+
+ private:
+  // This object is deleted on the UI thread after the IO thread has been
+  // destroyed. Need to know when IO thread is being destroyed so that
+  // we can delete udev_.
+  virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
+
+  void Initialize();
+  void OnDevicesChanged(udev_device* device);
+
+  scoped_ptr<UdevLinux> udev_;
+
+  DISALLOW_COPY_AND_ASSIGN(DeviceMonitorLinux);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_DEVICE_MONITOR_LINUX_H_

content/content_browser.gypi

@@ -268,6 +268,8 @@
     'browser/debugger/worker_devtools_manager.h',
     'browser/debugger/worker_devtools_message_filter.cc',
     'browser/debugger/worker_devtools_message_filter.h',
+    'browser/device_monitor_linux.cc',
+    'browser/device_monitor_linux.h',
     'browser/device_orientation/accelerometer_mac.cc',
     'browser/device_orientation/accelerometer_mac.h',
     'browser/device_orientation/data_fetcher.h',