Cleanup RectangleUpdateDecoder and VideoStub

remoting/client/rectangle_update_decoder.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 REMOTING_CLIENT_RECTANGLE_UPDATE_DECODER_H_
 #define REMOTING_CLIENT_RECTANGLE_UPDATE_DECODER_H_
 
 #include <list>
 
-#include "base/callback.h"
+#include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "remoting/codec/video_decoder.h"
 #include "remoting/client/chromoting_stats.h"
 #include "remoting/client/frame_consumer_proxy.h"
 #include "remoting/client/frame_producer.h"
 #include "remoting/protocol/video_stub.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }  // namespace base
 
 namespace pp {
 class ImageData;
-};
+}  // namespace pp
 
 namespace remoting {
 
 class ChromotingStats;
-class VideoPacket;
 
 namespace protocol {
 class SessionConfig;
 }  // namespace protocol
 
 // TODO(ajwong): Re-examine this API, especially with regards to how error
 // conditions on each step are reported.  Should they be CHECKs? Logs? Other?
 // TODO(sergeyu): Rename this class.
 class RectangleUpdateDecoder
     : public base::RefCountedThreadSafe<RectangleUpdateDecoder>,
       public FrameProducer,
       public protocol::VideoStub {
  public:
   // Creates an update decoder on |main_task_runner_| and |decode_task_runner_|,
   // outputting to |consumer|. The |main_task_runner_| is responsible for
   // receiving and queueing packets. The |decode_task_runner_| is responsible
   // for decoding the video packets.
   // TODO(wez): Replace the ref-counted proxy with an owned FrameConsumer.
   RectangleUpdateDecoder(
       scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
       scoped_refptr<base::SingleThreadTaskRunner> decode_task_runner,
       scoped_refptr<FrameConsumerProxy> consumer);
 
   // Initializes decoder with the information from the protocol config.
   void Initialize(const protocol::SessionConfig& config);
 
-  // Removes all video packets in the queue.
-  void DropAllPackets();
+  // Stop decoding of any pending video packets.
+  void Stop();
 
   // FrameProducer implementation.  These methods may be called before we are
   // Initialize()d, or we know the source screen size.
   virtual void DrawBuffer(pp::ImageData* buffer) OVERRIDE;
   virtual void InvalidateRegion(const SkRegion& region) OVERRIDE;
   virtual void RequestReturnBuffers(const base::Closure& done) OVERRIDE;
   virtual void SetOutputSizeAndClip(const SkISize& view_size,
                                     const SkIRect& clip_area) OVERRIDE;
 
   // VideoStub implementation.
   virtual void ProcessVideoPacket(scoped_ptr<VideoPacket> packet,
                                   const base::Closure& done) OVERRIDE;
-  virtual int GetPendingVideoPackets() OVERRIDE;
 
   // Return the stats recorded by this client.
   ChromotingStats* GetStats();
 
  private:
-  struct QueuedVideoPacket {
-    QueuedVideoPacket(scoped_ptr<VideoPacket> packet,
-                      const base::Closure& done);
-    ~QueuedVideoPacket();
-    VideoPacket* packet;
-    base::Closure done;
-  };
-
   friend class base::RefCountedThreadSafe<RectangleUpdateDecoder>;
   virtual ~RectangleUpdateDecoder();
 
   // Paints the invalidated region to the next available buffer and returns it
   // to the consumer.
   void SchedulePaint();
   void DoPaint();
 
-  // If a packet is not being processed, dispatches a single message from the
-  // |received_packets_| queue.
-  void ProcessNextPacket();
-
   // Decodes the contents of |packet|. DecodePacket may keep a reference to
   // |packet| so the |packet| must remain alive and valid until |done| is
   // executed.
   void DecodePacket(scoped_ptr<VideoPacket> packet, const base::Closure& done);
 
   // Callback method when a VideoPacket is processed.
   // If |last_packet| is true then |decode_start| contains the timestamp when
   // the packet will start to be processed.
-  void OnPacketDone(bool last_packet, base::Time decode_start);
+  void OnPacketDone(bool last_packet,
+                    base::Time decode_start,
+                    const base::Closure& done);
 
   scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> decode_task_runner_;
   scoped_refptr<FrameConsumerProxy> consumer_;
   scoped_ptr<VideoDecoder> decoder_;
 
   // Remote screen size in pixels.
   SkISize source_size_;
 
   // Vertical and horizontal DPI of the remote screen.
   SkIPoint source_dpi_;
 
   // The current dimensions of the frame consumer view.
   SkISize view_size_;
   SkIRect clip_area_;
 
   // The drawing buffers supplied by the frame consumer.
   std::list<pp::ImageData*> buffers_;
 
   // Flag used to coalesce runs of SchedulePaint()s into a single DoPaint().
   bool paint_scheduled_;
 
-  // Contains all video packets that have been received, but have not yet been
-  // processed.
-  //
-  // Used to serialize sending of messages to the client.
-  // TODO(sergeyu): Simplify this code and remove this list.
-  std::list<QueuedVideoPacket> received_packets_;
-
-  // True if a message is being processed. Can be used to determine if it is
-  // safe to dispatch another message.
-  bool packet_being_processed_;
+  // Set to true after Stop() has been called.

[Wez, 2012/08/28 16:42:27]

nit: True after Stop() has been called.
The current wording sounds like an instruction. :)

[Sergey Ulanov, 2012/08/28 18:30:27]

Done.

+  bool stopped_;
 
   ChromotingStats stats_;
 
   // Keep track of the most recent sequence number bounced back from the host.
   int64 latest_sequence_number_;
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_CLIENT_RECTANGLE_UPDATE_DECODER_H_