Add a new parameter |latency| to PPB_Audio.

ppapi/shared_impl/ppb_audio_shared.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.
 
 #ifndef PPAPI_SHARED_IMPL_PPB_AUDIO_SHARED_H_
 #define PPAPI_SHARED_IMPL_PPB_AUDIO_SHARED_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/shared_memory.h"
 #include "base/sync_socket.h"
 #include "base/threading/simple_thread.h"
 #include "media/base/audio_bus.h"
 #include "ppapi/c/ppb_audio.h"
+#include "ppapi/c/ppb_audio_config.h"
 #include "ppapi/shared_impl/resource.h"
 #include "ppapi/thunk/ppb_audio_api.h"
 
 #if defined(OS_NACL)
 #include "native_client/src/untrusted/irt/irt_ppapi.h"
 #endif
 
 namespace ppapi {
 
+class PPAPI_SHARED_EXPORT AudioCallback {

[dmichael (off chromium), 2013/08/06 19:43:25]

We used the suffix "Combined" in another place where we have >1 way to talk to
the plugin...  PPPInstanceCombined. It might be helpful to follow that
convention here.

[yzshen1, 2013/08/07 20:51:06]

Done.

+ public:
+  AudioCallback();
+  AudioCallback(PPB_Audio_Callback_1_0 callback_1_0);
+  AudioCallback(PPB_Audio_Callback callback);

[dmichael (off chromium), 2013/08/06 19:43:25]

nit: explicit for both of these

[yzshen1, 2013/08/07 20:51:06]

Done.

+
+  ~AudioCallback();
+
+  bool IsValid() const;
+
+  void Run(void* sample_buffer,
+           uint32_t buffer_size_in_bytes,
+           PP_TimeDelta latency,
+           void* user_data) const;
+
+ private:
+  PPB_Audio_Callback_1_0 callback_1_0_;
+  PPB_Audio_Callback callback_;
+};
+
 // Implements the logic to map shared memory and run the audio thread signaled
 // from the sync socket. Both the proxy and the renderer implementation use
 // this code.
 class PPAPI_SHARED_EXPORT PPB_Audio_Shared
     : public thunk::PPB_Audio_API,
       public base::DelegateSimpleThread::Delegate {
  public:
   PPB_Audio_Shared();
   virtual ~PPB_Audio_Shared();
 
   bool playing() const { return playing_; }
 
   // Sets the callback information that the background thread will use. This
   // is optional. Without a callback, the thread will not be run. This
   // non-callback mode is used in the renderer with the proxy, since the proxy
   // handles the callback entirely within the plugin process.
-  void SetCallback(PPB_Audio_Callback callback, void* user_data);
+  void SetCallback(const AudioCallback& callback, void* user_data);
 
   // Configures the current state to be playing or not. The caller is
   // responsible for ensuring the new state is the opposite of the current one.
   //
   // This is the implementation for PPB_Audio.Start/StopPlayback, except that
   // it does not actually notify the audio system to stop playback, it just
   // configures our object to stop generating callbacks. The actual stop
   // playback request will be done in the derived classes and will be different
   // from the proxy and the renderer.
   void SetStartPlaybackState();
   void SetStopPlaybackState();
 
   // Sets the shared memory and socket handles. This will automatically start
   // playback if we're currently set to play.
   void SetStreamInfo(PP_Instance instance,
                      base::SharedMemoryHandle shared_memory_handle,
                      size_t shared_memory_size,
                      base::SyncSocket::Handle socket_handle,
+                     PP_AudioSampleRate sample_rate,
                      int sample_frame_count);
 
 #if defined(OS_NACL)
   // NaCl has a special API for IRT code to create threads that can call back
   // into user code.
   static void SetThreadFunctions(const struct PP_ThreadFunctions* functions);
 #endif
 
  private:
   // Starts execution of the audio thread.
@@ skipping 24 matching lines @@
   // When the callback is set, this thread is spawned for calling it.
   scoped_ptr<base::DelegateSimpleThread> audio_thread_;
 #else
   uintptr_t thread_id_;
   bool thread_active_;
 
   static void CallRun(void* self);
 #endif
 
   // Callback to call when audio is ready to accept new samples.
-  PPB_Audio_Callback callback_;
+  AudioCallback callback_;
 
   // User data pointer passed verbatim to the callback function.
   void* user_data_;
 
   // AudioBus for shuttling data across the shared memory.
   scoped_ptr<media::AudioBus> audio_bus_;
 
   // Internal buffer for client's integer audio data.
   int client_buffer_size_bytes_;
   scoped_ptr<uint8_t[]> client_buffer_;
 
+  // The size (in bytes) of one second of audio data. Used to calculate latency.
+  size_t bytes_per_second_;
+
   DISALLOW_COPY_AND_ASSIGN(PPB_Audio_Shared);
 };
 
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_PPB_AUDIO_SHARED_H_