PPB_AudioInput_Dev: support multiple audio input devices - Part 1.

ppapi/cpp/dev/audio_input_dev.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
 #ifndef PPAPI_CPP_DEV_AUDIO_INPUT_DEV_H_
 #define PPAPI_CPP_DEV_AUDIO_INPUT_DEV_H_
 
+#include <vector>
+
 #include "ppapi/c/dev/ppb_audio_input_dev.h"
 #include "ppapi/cpp/audio_config.h"
 #include "ppapi/cpp/resource.h"
 
 namespace pp {
 
+class CompletionCallback;
+class DeviceRef_Dev;
 class InstanceHandle;
 
 class AudioInput_Dev : public Resource {
  public:
   /// An empty constructor for an AudioInput resource.
-  AudioInput_Dev() {}
+  AudioInput_Dev();
 
+  /// This constructor tries to create an audio input resource using the v0.2
+  /// interface, and falls back on the v0.1 interface if that is not available.
+  /// Please use the 2-parameter Open() if you used this constructor.
+  ///
+  /// Note: This constructor is deprecated. Unless your code has to deal with
+  /// browsers that only support the v0.1 interface, please use the 1-parameter
+  /// constructor instead.
   AudioInput_Dev(const InstanceHandle& instance,
                  const AudioConfig& config,
                  PPB_AudioInput_Callback callback,
                  void* user_data);
 
+  /// This constructor uses the v0.2 interface to create an audio input
+  /// resource. Please use the 5-parameter Open() if you used this constructor.
+  explicit AudioInput_Dev(const InstanceHandle& instance);
+
+  AudioInput_Dev(const AudioInput_Dev& other);
+
+  virtual ~AudioInput_Dev();
+
+  AudioInput_Dev& operator=(const AudioInput_Dev& other);
+
   /// Static function for determining whether the browser supports the required
   /// AudioInput interface.
   ///
   /// @return true if the interface is available, false otherwise.
   static bool IsAvailable();
 
   /// Getter function for returning the internal <code>PPB_AudioConfig</code>
   /// struct.
   ///
   /// @return A mutable reference to the PPB_AudioConfig struct.
   AudioConfig& config() { return config_; }
 
   /// Getter function for returning the internal <code>PPB_AudioConfig</code>
   /// struct.
   ///
   /// @return A const reference to the internal <code>PPB_AudioConfig</code>
   /// struct.
   const AudioConfig& config() const { return config_; }
 
+  /// |devices| must stay alive until either this AudioInput_Dev object goes
+  /// away or |callback| is run, if this method returns PP_OK_COMPLETIONPENDING.
+  int32_t EnumerateDevices(std::vector<DeviceRef_Dev>* devices,
+                           const CompletionCallback& callback);
+
+  /// If |device_ref| is null (i.e., is_null() returns true), the default device
+  /// will be used.
+  /// In order to maintain backward compatibility, this method doesn't have
+  /// input parameters config, audio_input_callback and user_data. Instead, it
+  /// uses those values stored when the 4-parameter constructor was called.
+  ///
+  /// Note: This method is deprecated. Unless your code has to deal with
+  /// browsers that only support the v0.1 interface, please use the other
+  /// Open().
+  int32_t Open(const DeviceRef_Dev& device_ref,
+               const CompletionCallback& callback);
+
+  int32_t Open(const DeviceRef_Dev& device_ref,
+               const AudioConfig& config,
+               PPB_AudioInput_Callback audio_input_callback,
+               void* user_data,
+               const CompletionCallback& callback);
+
   bool StartCapture();
   bool StopCapture();
+  void Close();
 
  private:
+  struct EnumerateDevicesState;
+
+  void AbortEnumerateDevices();
+
+  // |user_data| is an EnumerateDevicesState object. It is this method's
+  // responsibility to delete it.
+  static void OnEnumerateDevicesComplete(void* user_data, int32_t result);
+
   AudioConfig config_;
+
+  // It is set in EnumerateDevices(), and cleared in AbortEnumerateDevices() or
+  // OnEnumerateDevicesComplete(). The object will be deleted by
+  // OnEnumerateDevicesComplete().
+  EnumerateDevicesState* enum_state_;
+
+  // Used to store the arguments of Open() for the v0.2 interface.
+  PPB_AudioInput_Callback audio_input_callback_;
+  void* user_data_;
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_DEV_AUDIO_INPUT_DEV_H_