Cast: cancel re-sending if a later nack packet says the receiver doesn't want it anymore

media/cast/transport/pacing/paced_sender.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 MEDIA_CAST_TRANSPORT_PACING_PACED_SENDER_H_
 #define MEDIA_CAST_TRANSPORT_PACING_PACED_SENDER_H_
 
 #include <list>
 #include <vector>
 
@@ skipping 25 matching lines @@
 //    means that older packets are sent first.
 typedef std::pair<base::TimeTicks, std::pair<uint32, uint16> > PacketKey;
 typedef std::vector<std::pair<PacketKey, PacketRef> > SendPacketVector;
 
 // We have this pure virtual class to enable mocking.
 class PacedPacketSender {
  public:
   virtual bool SendPackets(const SendPacketVector& packets) = 0;
   virtual bool ResendPackets(const SendPacketVector& packets) = 0;
   virtual bool SendRtcpPacket(uint32 ssrc, PacketRef packet) = 0;
+  virtual void CancelSendingPacket(const PacketKey& packet_key) = 0;
 
   virtual ~PacedPacketSender() {}
 
   static PacketKey MakePacketKey(const base::TimeTicks& ticks,
                                  uint32 ssrc,
                                  uint16 packet_id);
 };
 
 class PacedSender : public PacedPacketSender,
                     public base::NonThreadSafe,
@@ skipping 10 matching lines @@
   virtual ~PacedSender();
 
   // These must be called before non-RTCP packets are sent.
   void RegisterAudioSsrc(uint32 audio_ssrc);
   void RegisterVideoSsrc(uint32 video_ssrc);
 
   // PacedPacketSender implementation.
   virtual bool SendPackets(const SendPacketVector& packets) OVERRIDE;
   virtual bool ResendPackets(const SendPacketVector& packets) OVERRIDE;
   virtual bool SendRtcpPacket(uint32 ssrc, PacketRef packet) OVERRIDE;
+  virtual void CancelSendingPacket(const PacketKey& packet_key) OVERRIDE;
 
  private:
   // Actually sends the packets to the transport.
   void SendStoredPackets();
   void LogPacketEvent(const Packet& packet, bool retransmit);
 
   enum PacketType {
     PacketType_RTCP,
     PacketType_Resend,
     PacketType_Normal
@@ skipping 45 matching lines @@
   base::WeakPtrFactory<PacedSender> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PacedSender);
 };
 
 }  // namespace transport
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_TRANSPORT_PACING_PACED_SENDER_H_