Audio output debug recording.

media/audio/audio_output_resampler.cc

Index: media/audio/audio_output_resampler.cc
diff --git a/media/audio/audio_output_resampler.cc b/media/audio/audio_output_resampler.cc
index 9439a634fcdb45a6e38d32768662c8310a5c888e..f27fd8104c09f0a68f247dcbd8c1f7484ced159e 100644
--- a/media/audio/audio_output_resampler.cc
+++ b/media/audio/audio_output_resampler.cc
@@ -28,12 +28,23 @@
 
 namespace media {
 
+namespace {
+
+// Helper function for when we have no debug recording register callback.
+std::unique_ptr<AudioDebugRecorder> GetNullptrAudioDebugRecorder(
+    const AudioParameters& params) {
+  return nullptr;
+}
+
+}  // namespace
+
 class OnMoreDataConverter
     : public AudioOutputStream::AudioSourceCallback,
       public AudioConverter::InputCallback {
  public:
   OnMoreDataConverter(const AudioParameters& input_params,
-                      const AudioParameters& output_params);
+                      const AudioParameters& output_params,
+                      std::unique_ptr<AudioDebugRecorder> debug_recorder);
   ~OnMoreDataConverter() override;
 
   // AudioSourceCallback interface.
@@ -84,6 +95,9 @@ class OnMoreDataConverter
   const int input_buffer_size_;
   const int output_buffer_size_;
 
+  // For audio debug recordings.
+  std::unique_ptr<AudioDebugRecorder> debug_recorder_;
+
   DISALLOW_COPY_AND_ASSIGN(OnMoreDataConverter);
 };
 
@@ -215,11 +229,14 @@ void AudioOutputResampler::SetupFallbackParams() {
 #endif
 }
 
-AudioOutputResampler::AudioOutputResampler(AudioManager* audio_manager,
-                                           const AudioParameters& input_params,
-                                           const AudioParameters& output_params,
-                                           const std::string& output_device_id,
-                                           const base::TimeDelta& close_delay)
+AudioOutputResampler::AudioOutputResampler(
+    AudioManager* audio_manager,
+    const AudioParameters& input_params,
+    const AudioParameters& output_params,
+    const std::string& output_device_id,
+    base::TimeDelta close_delay,
+    const RegisterDebugRecordingSourceCallback&
+        register_debug_recording_source_callback)
     : AudioOutputDispatcher(audio_manager, input_params, output_device_id),
       close_delay_(close_delay),
       output_params_(output_params),
@@ -230,6 +247,10 @@ AudioOutputResampler::AudioOutputResampler(AudioManager* audio_manager,
                           base::Bind(&AudioOutputResampler::Reinitialize,
                                      base::Unretained(this)),
                           false),
+      register_debug_recording_source_callback_(
+          register_debug_recording_source_callback
+              ? register_debug_recording_source_callback
+              : base::BindRepeating(&GetNullptrAudioDebugRecorder)),

[o1ka, 2017/02/10 15:21:53]

Pass this into constructor instead? Why to deffer the decision to
AudioOutputResampler, when everything is know before its creation?

[Henrik Grunell, 2017/02/13 15:16:48]

Absolutely, done.

       weak_factory_(this) {
   DCHECK(input_params.IsValid());
   DCHECK(output_params.IsValid());
@@ -341,7 +362,12 @@ bool AudioOutputResampler::StartStream(
   OnMoreDataConverter* resampler_callback = nullptr;
   CallbackMap::iterator it = callbacks_.find(stream_proxy);
   if (it == callbacks_.end()) {
-    resampler_callback = new OnMoreDataConverter(params_, output_params_);
+    // If a register callback has been given, register and pass the returned
+    // recoder to the converter. Data is fed to same recorder for the lifetime
+    // of the converter, which is until the stream is closed.
+    resampler_callback = new OnMoreDataConverter(
+        params_, output_params_,
+        register_debug_recording_source_callback_.Run(output_params_));
     callbacks_[stream_proxy] =
         base::WrapUnique<OnMoreDataConverter>(resampler_callback);
   } else {
@@ -408,8 +434,10 @@ void AudioOutputResampler::StopStreamInternal(
     dispatcher_->CloseAllIdleStreams();
 }
 
-OnMoreDataConverter::OnMoreDataConverter(const AudioParameters& input_params,
-                                         const AudioParameters& output_params)
+OnMoreDataConverter::OnMoreDataConverter(
+    const AudioParameters& input_params,
+    const AudioParameters& output_params,
+    std::unique_ptr<AudioDebugRecorder> debug_recorder)
     : io_ratio_(static_cast<double>(input_params.GetBytesPerSecond()) /
                 output_params.GetBytesPerSecond()),
       source_callback_(nullptr),
@@ -417,7 +445,8 @@ OnMoreDataConverter::OnMoreDataConverter(const AudioParameters& input_params,
       audio_converter_(input_params, output_params, false),
       error_occurred_(false),
       input_buffer_size_(input_params.frames_per_buffer()),
-      output_buffer_size_(output_params.frames_per_buffer()) {
+      output_buffer_size_(output_params.frames_per_buffer()),
+      debug_recorder_(std::move(debug_recorder)) {
   RecordRebufferingStats(input_params, output_params);
 }
 
@@ -454,6 +483,9 @@ int OnMoreDataConverter::OnMoreData(base::TimeDelta delay,
   current_delay_timestamp_ = delay_timestamp;
   audio_converter_.Convert(dest);
 
+  if (debug_recorder_)
+    debug_recorder_->OnData(dest);
+
   // Always return the full number of frames requested, ProvideInput()
   // will pad with silence if it wasn't able to acquire enough data.
   return dest->frames();