Adding key press detection in the browser process.

media/audio/audio_input_controller.cc

Index: media/audio/audio_input_controller.cc
diff --git a/media/audio/audio_input_controller.cc b/media/audio/audio_input_controller.cc
index 31e137e2b17e4442c00979e85cbcffa31cd53cba..11673522c5109c9e0f2274e5522930f9a0b4e3b4 100644
--- a/media/audio/audio_input_controller.cc
+++ b/media/audio/audio_input_controller.cc
@@ -36,14 +36,17 @@ namespace media {
 AudioInputController::Factory* AudioInputController::factory_ = NULL;
 
 AudioInputController::AudioInputController(EventHandler* handler,
-                                           SyncWriter* sync_writer)
+                                           SyncWriter* sync_writer,
+                                           KeyPressMonitor* key_press_monitor)
     : creator_loop_(base::MessageLoopProxy::current()),
       handler_(handler),
       stream_(NULL),
       data_is_active_(false),
       state_(kEmpty),
       sync_writer_(sync_writer),
-      max_volume_(0.0) {
+      max_volume_(0.0),
+      key_press_monitor_(key_press_monitor),
+      key_pressed_(false) {
   DCHECK(creator_loop_.get());
 }
 
@@ -56,17 +59,19 @@ scoped_refptr<AudioInputController> AudioInputController::Create(
     AudioManager* audio_manager,
     EventHandler* event_handler,
     const AudioParameters& params,
-    const std::string& device_id) {
+    const std::string& device_id,
+    KeyPressMonitor* key_press_monitor) {
   DCHECK(audio_manager);
 
   if (!params.IsValid() || (params.channels() > kMaxInputChannels))
     return NULL;
 
-  if (factory_)
-    return factory_->Create(audio_manager, event_handler, params);
-
-  scoped_refptr<AudioInputController> controller(new AudioInputController(
-      event_handler, NULL));
+  if (factory_) {
+    return factory_->Create(
+        audio_manager, event_handler, params, key_press_monitor);
+  }
+  scoped_refptr<AudioInputController> controller(
+      new AudioInputController(event_handler, NULL, key_press_monitor));
 
   controller->message_loop_ = audio_manager->GetMessageLoop();
 
@@ -87,7 +92,8 @@ scoped_refptr<AudioInputController> AudioInputController::CreateLowLatency(
     EventHandler* event_handler,
     const AudioParameters& params,
     const std::string& device_id,
-    SyncWriter* sync_writer) {
+    SyncWriter* sync_writer,
+    KeyPressMonitor* key_press_monitor) {
   DCHECK(audio_manager);
   DCHECK(sync_writer);
 
@@ -96,8 +102,8 @@ scoped_refptr<AudioInputController> AudioInputController::CreateLowLatency(
 
   // Create the AudioInputController object and ensure that it runs on
   // the audio-manager thread.
-  scoped_refptr<AudioInputController> controller(new AudioInputController(
-      event_handler, sync_writer));
+  scoped_refptr<AudioInputController> controller(
+      new AudioInputController(event_handler, sync_writer, key_press_monitor));
   controller->message_loop_ = audio_manager->GetMessageLoop();
 
   // Create and open a new audio input stream from the existing
@@ -116,14 +122,15 @@ scoped_refptr<AudioInputController> AudioInputController::CreateForStream(
     const scoped_refptr<base::MessageLoopProxy>& message_loop,
     EventHandler* event_handler,
     AudioInputStream* stream,
-    SyncWriter* sync_writer) {
+    SyncWriter* sync_writer,
+    KeyPressMonitor* key_press_monitor) {
   DCHECK(sync_writer);
   DCHECK(stream);
 
   // Create the AudioInputController object and ensure that it runs on
   // the audio-manager thread.
-  scoped_refptr<AudioInputController> controller(new AudioInputController(
-      event_handler, sync_writer));
+  scoped_refptr<AudioInputController> controller(
+      new AudioInputController(event_handler, sync_writer, key_press_monitor));
   controller->message_loop_ = message_loop;
 
   // TODO(miu): See TODO at top of file.  Until that's resolved, we need to
@@ -233,6 +240,8 @@ void AudioInputController::DoRecord() {
 
   stream_->Start(this);
   handler_->OnRecording(this);
+
+  key_press_monitor_->AddKeyPressListener(this);
 }
 
 void AudioInputController::DoClose() {
@@ -252,6 +261,7 @@ void AudioInputController::DoClose() {
 
     state_ = kClosed;
   }
+  key_press_monitor_->RemoveKeyPressListener(this);
 }
 
 void AudioInputController::DoReportError() {
@@ -320,10 +330,14 @@ void AudioInputController::DoCheckForNoData() {
 void AudioInputController::OnData(AudioInputStream* stream, const uint8* data,
                                   uint32 size, uint32 hardware_delay_bytes,
                                   double volume) {
+  bool key_pressed;
   {
     base::AutoLock auto_lock(lock_);
     if (state_ != kRecording)
       return;
+
+    key_pressed = key_pressed_;

[DaleCurtis, 2013/08/02 01:01:17]

You could initialize key_pressed to false above and then use std::swap() here. 
Up to you, I find it preferable to an uninitialized variable.

[jiayl, 2013/08/02 20:32:20]

Done.

+    key_pressed_ = false;
   }
 
   // Mark data as active to ensure that the periodic calls to
@@ -332,7 +346,7 @@ void AudioInputController::OnData(AudioInputStream* stream, const uint8* data,
 
   // Use SyncSocket if we are in a low-latency mode.
   if (LowLatencyMode()) {
-    sync_writer_->Write(data, size, volume);
+    sync_writer_->Write(data, size, volume, key_pressed);
     sync_writer_->UpdateRecordedBytes(hardware_delay_bytes);
     return;
   }
@@ -353,8 +367,13 @@ void AudioInputController::OnError(AudioInputStream* stream) {
       &AudioInputController::DoReportError, this));
 }
 
+void AudioInputController::OnKeyPressed() {
+  base::AutoLock auto_lock(lock_);
+  key_pressed_ = true;
+}
+
 void AudioInputController::DoStopCloseAndClearStream(
-    base::WaitableEvent *done) {
+    base::WaitableEvent* done) {
   DCHECK(message_loop_->BelongsToCurrentThread());
 
   // Allow calling unconditionally and bail if we don't have a stream to close.