Make VEA client of command buffer; move sync. IPC to VDA/VEA::Initialize()

content/common/gpu/client/gpu_video_encode_accelerator_host.h

 // Copyright 2013 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 CONTENT_COMMON_GPU_CLIENT_GPU_VIDEO_ENCODE_ACCELERATOR_HOST_H_
 #define CONTENT_COMMON_GPU_CLIENT_GPU_VIDEO_ENCODE_ACCELERATOR_HOST_H_
 
 #include <vector>
 
 #include "base/containers/hash_tables.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
+#include "base/threading/non_thread_safe.h"
+#include "content/common/gpu/client/command_buffer_proxy_impl.h"
 #include "ipc/ipc_listener.h"
 #include "media/video/video_encode_accelerator.h"
 
 namespace gfx {
 
 class Size;
 
 }  // namespace gfx
 
 namespace media {
 
 class VideoFrame;
 
 }  // namespace media
 
 namespace content {
 
 class GpuChannelHost;
 
 // This class is the renderer-side host for the VideoEncodeAccelerator in the
 // GPU process, coordinated over IPC.
 class GpuVideoEncodeAcceleratorHost
     : public IPC::Listener,
       public media::VideoEncodeAccelerator,
-      public base::SupportsWeakPtr<GpuVideoEncodeAcceleratorHost> {
+      public CommandBufferProxyImpl::DeletionObserver,
+      public base::NonThreadSafe {
  public:
-  // Since the GpuChannelHost does _not_ own this object, a reference to
-  // |gpu_channel_host| is taken.
-  GpuVideoEncodeAcceleratorHost(
-      const scoped_refptr<GpuChannelHost>& gpu_channel_host,
-      int32 route_id);
-  virtual ~GpuVideoEncodeAcceleratorHost();
+  // |this| is guaranteed not to outlive |channel| and |impl|.  (See comments
+  // for |channel_| and |impl_|.)
+  GpuVideoEncodeAcceleratorHost(GpuChannelHost* channel,
+                                CommandBufferProxyImpl* impl);
 
   // Static query for the supported profiles.  This query proxies to
   // GpuVideoEncodeAccelerator::GetSupportedProfiles().
   static std::vector<SupportedProfile> GetSupportedProfiles();
 
   // IPC::Listener implementation.
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
   virtual void OnChannelError() OVERRIDE;
 
   // media::VideoEncodeAccelerator implementation.
-  virtual void Initialize(media::VideoFrame::Format format,
+  virtual bool Initialize(media::VideoFrame::Format input_format,
                           const gfx::Size& input_visible_size,
                           media::VideoCodecProfile output_profile,
                           uint32 initial_bitrate,
                           Client* client) OVERRIDE;
   virtual void Encode(const scoped_refptr<media::VideoFrame>& frame,
                       bool force_keyframe) OVERRIDE;
   virtual void UseOutputBitstreamBuffer(
       const media::BitstreamBuffer& buffer) OVERRIDE;
   virtual void RequestEncodingParametersChange(uint32 bitrate,
                                                uint32 framerate_num) OVERRIDE;
   virtual void Destroy() OVERRIDE;
 
+  // CommandBufferProxyImpl::DeletionObserver implemetnation.
+  virtual void OnWillDeleteImpl() OVERRIDE;
+
  private:
-  // Notify |client_| when an error has occured.  Used when notifying from
-  // within a media::VideoEncodeAccelerator entry point, to avoid re-entrancy.
-  void NotifyError(Error error);
+  // Only Destroy() should be deleting |this|.
+  virtual ~GpuVideoEncodeAcceleratorHost();
+
+  // Notify |client_| of an error.  Posts a task to avoid re-entrancy.
+  void PostNotifyError(Error);
+
+  void Send(IPC::Message* message);
 
   // IPC handlers, proxying media::VideoEncodeAccelerator::Client for the GPU
-  // process.
-  void OnNotifyInitializeDone();
+  // process.  Should not be called directly.
   void OnRequireBitstreamBuffers(uint32 input_count,
                                  const gfx::Size& input_coded_size,
                                  uint32 output_buffer_size);
   void OnNotifyInputDone(int32 frame_id);
   void OnBitstreamBufferReady(int32 bitstream_buffer_id,
                               uint32 payload_size,
                               bool key_frame);
   void OnNotifyError(Error error);
 
-  void Send(IPC::Message* message);
+  // Unowned reference to the GpuChannelHost to send IPC messages to the GPU
+  // process.  |channel_| outlives |impl_|, so the reference is always valid as
+  // long as it is not NULL.
+  GpuChannelHost* channel_;
 
-  // Pointer for client callbacks on the media::VideoEncodeAccelerator::Client
-  // interface.
+  // Route ID for the associated encoder in the GPU process.
+  int32 encoder_route_id_;
+
+  // The client that will receive callbacks from the encoder.
   Client* client_;
-  // |client_ptr_factory_| is used for callbacks that need to be done through
-  // a PostTask() to avoid re-entrancy on the client.
-  scoped_ptr<base::WeakPtrFactory<Client> > client_ptr_factory_;
 
-  // IPC channel and route ID.
-  scoped_refptr<GpuChannelHost> channel_;
-  const int32 route_id_;
+  // Unowned reference to the CommandBufferProxyImpl that created us.  |this|
+  // registers as a DeletionObserver of |impl_|, so the reference is always
+  // valid as long as it is not NULL.
+  CommandBufferProxyImpl* impl_;
 
   // media::VideoFrames sent to the encoder.
   // base::IDMap not used here, since that takes pointers, not scoped_refptr.
   typedef base::hash_map<int32, scoped_refptr<media::VideoFrame> > FrameMap;
   FrameMap frame_map_;
 
   // ID serial number for the next frame to send to the GPU process.
   int32 next_frame_id_;
 
+  // WeakPtr factory for posting tasks back to itself.
+  base::WeakPtrFactory<GpuVideoEncodeAcceleratorHost> weak_this_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(GpuVideoEncodeAcceleratorHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_CLIENT_GPU_VIDEO_ENCODE_ACCELERATOR_HOST_H_