Cast: Reshuffle files under media/cast

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>
-
-#include "base/basictypes.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/memory/weak_ptr.h"
-#include "base/single_thread_task_runner.h"
-#include "base/threading/non_thread_safe.h"
-#include "base/time/default_tick_clock.h"
-#include "base/time/tick_clock.h"
-#include "base/time/time.h"
-#include "media/cast/transport/cast_transport_config.h"
-#include "media/cast/transport/transport/udp_transport.h"
-
-namespace media {
-namespace cast {
-
-class LoggingImpl;
-
-namespace transport {
-
-// Use std::pair for free comparison operators.
-// { capture_time, ssrc, packet_id }
-// The PacketKey is designed to meet two criteria:
-// 1. When we re-send the same packet again, we can use the packet key
-//    to identify it so that we can de-duplicate packets in the queue.
-// 2. The sort order of the PacketKey determines the order that packets
-//    are sent out. Using the capture_time as the first member basically
-//    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,
-                             base::TimeDelta dedupe_window) = 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,
-                    public base::SupportsWeakPtr<PacedSender> {
- public:
-  // The |external_transport| should only be used by the Cast receiver and for
-  // testing.
-  PacedSender(
-      base::TickClock* clock,
-      LoggingImpl* logging,
-      PacketSender* external_transport,
-      const scoped_refptr<base::SingleThreadTaskRunner>& transport_task_runner);
-
-  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,
-                             base::TimeDelta dedupe_window) 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, CastLoggingEvent event);
-
-  enum PacketType {
-    PacketType_RTCP,
-    PacketType_Resend,
-    PacketType_Normal
-  };
-  enum State {
-    // In an unblocked state, we can send more packets.
-    // We have to check the current time against |burst_end_| to see if we are
-    // appending to the current burst or if we can start a new one.
-    State_Unblocked,
-    // In this state, we are waiting for a callback from the udp transport.
-    // This happens when the OS-level buffer is full. Once we receive the
-    // callback, we go to State_Unblocked and see if we can write more packets
-    // to the current burst. (Or the next burst if enough time has passed.)
-    State_TransportBlocked,
-    // Once we've written enough packets for a time slice, we go into this
-    // state and PostDelayTask a call to ourselves to wake up when we can
-    // send more data.
-    State_BurstFull
-  };
-
-  bool empty() const;
-  size_t size() const;
-
-  // Returns the next packet to send. RTCP packets have highest priority,
-  // resend packets have second highest priority and then comes everything
-  // else.
-  PacketRef GetNextPacket(PacketType* packet_type,
-                          PacketKey* packet_key);
-
-  base::TickClock* const clock_;  // Not owned by this class.
-  LoggingImpl* const logging_;    // Not owned by this class.
-  PacketSender* transport_;       // Not owned by this class.
-  scoped_refptr<base::SingleThreadTaskRunner> transport_task_runner_;
-  uint32 audio_ssrc_;
-  uint32 video_ssrc_;
-  std::map<PacketKey, std::pair<PacketType, PacketRef> > packet_list_;
-  std::map<PacketKey, base::TimeTicks> sent_time_;
-  std::map<PacketKey, base::TimeTicks> sent_time_buffer_;
-
-  // Maximum burst size for the next three bursts.
-  size_t max_burst_size_;
-  size_t next_max_burst_size_;
-  size_t next_next_max_burst_size_;
-  // Number of packets already sent in the current burst.
-  size_t current_burst_size_;
-  // This is when the current burst ends.
-  base::TimeTicks burst_end_;
-
-  State state_;
-
-  // NOTE: Weak pointers must be invalidated before all other member variables.
-  base::WeakPtrFactory<PacedSender> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(PacedSender);
-};
-
-}  // namespace transport
-}  // namespace cast
-}  // namespace media
-
-#endif  // MEDIA_CAST_TRANSPORT_PACING_PACED_SENDER_H_