Adds input device selection on Windows.

media/audio/win/audio_low_latency_input_win.h

 // Copyright (c) 2011 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.
 //
 // Implementation of AudioInputStream for Windows using Windows Core Audio
 // WASAPI for low latency capturing.
 //
 // Overview of operation:
 //
 // - An object of WASAPIAudioInputStream is created by the AudioManager
@@ skipping 60 matching lines @@
 
 // AudioInputStream implementation using Windows Core Audio APIs.
 class MEDIA_EXPORT WASAPIAudioInputStream
     : public AudioInputStream,
       public base::DelegateSimpleThread::Delegate {
  public:
   // The ctor takes all the usual parameters, plus |manager| which is the
   // the audio manager who is creating this object.
   WASAPIAudioInputStream(AudioManagerWin* manager,
                          const AudioParameters& params,
-                         ERole device_role);
+                         const std::string& device_id);
   // The dtor is typically called by the AudioManager only and it is usually
   // triggered by calling AudioInputStream::Close().
   virtual ~WASAPIAudioInputStream();
 
   // Implementation of AudioInputStream.
   virtual bool Open() OVERRIDE;
   virtual void Start(AudioInputCallback* callback) OVERRIDE;
   virtual void Stop() OVERRIDE;
   virtual void Close() OVERRIDE;
 
   // Retrieves the stream format that the audio engine uses for its internal
   // processing/mixing of shared-mode streams.
   static double HardwareSampleRate(ERole device_role);
 
   bool started() const { return started_; }
 
  private:
   // DelegateSimpleThread::Delegate implementation.
   virtual void Run() OVERRIDE;
 
   // Issues the OnError() callback to the |sink_|.
   void HandleError(HRESULT err);
 
   // The Open() method is divided into these sub methods.
-  HRESULT SetCaptureDevice(ERole device_role);
+  HRESULT SetCaptureDevice(const std::string& device_id);

[tommi (sloooow) - chröme, 2011/12/01 14:11:03]

if the device_id has already been handed to the class via the constructor,
shouldn't we skip passing it as a parameter here?
This is a bit confusing in the cc file.

[henrika (OOO until Aug 14), 2011/12/01 16:02:38]

Done.

   HRESULT ActivateCaptureDevice();
   HRESULT GetAudioEngineStreamFormat();
   bool DesiredFormatIsSupported();
   HRESULT InitializeAudioEngine();
 
   // Initializes the COM library for use by the calling thread and set the
   // thread's concurrency model to multi-threaded.
   base::win::ScopedCOMInitializer com_init_;
 
   // Our creator, the audio manager needs to be notified when we close.
@@ skipping 21 matching lines @@
   // is defined as the block of data which the user received in each
   // OnData() callback.
   size_t packet_size_frames_;
 
   // Size in bytes of each audio packet.
   size_t packet_size_bytes_;
 
   // Length of the audio endpoint buffer.
   size_t endpoint_buffer_size_frames_;
 
-  // Defines the role that the system has assigned to an audio endpoint device.
-  ERole device_role_;
+  // Contains the unique name of the selected endpoint device.
+  // Note that AudioManagerBase::kDefaultDeviceId represents the default
+  // device role and is not a valid ID as such.
+  std::string device_id_;
 
   // Conversion factor used in delay-estimation calculations.
   // Converts a raw performance counter value to 100-nanosecond unit.
   double perf_count_to_100ns_units_;
 
   // Conversion factor used in delay-estimation calculations.
   // Converts from milliseconds to audio frames.
   double ms_to_frame_count_;
 
   // Pointer to the object that will receive the recorded audio samples.
@@ skipping 14 matching lines @@
   // recorded.
   base::win::ScopedHandle audio_samples_ready_event_;
 
   // This event will be signaled when capturing shall stop.
   base::win::ScopedHandle stop_capture_event_;
 
   DISALLOW_COPY_AND_ASSIGN(WASAPIAudioInputStream);
 };
 
 #endif  // MEDIA_AUDIO_WIN_AUDIO_LOW_LATENCY_INPUT_WIN_H_