src/media/cast/net/cast_transport_sender_impl.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // This class maintains a send transport for audio and video in a Cast
   6 // Streaming session.
   7 // Audio, video frames and RTCP messages are submitted to this object
   8 // and then packetized and paced to the underlying UDP socket.
   9 //
  10 // The hierarchy of send transport in a Cast Streaming session:
  11 //
  12 // CastTransportSender              RTP                      RTCP
  13 // ------------------------------------------------------------------
  14 //                      TransportEncryptionHandler (A/V)
  15 //                      RtpSender (A/V)                   Rtcp (A/V)
  16 //                                      PacedSender (Shared)
  17 //                                      UdpTransport (Shared)
  18 //
  19 // There are objects of TransportEncryptionHandler, RtpSender and Rtcp
  20 // for each audio and video stream.
  21 // PacedSender and UdpTransport are shared between all RTP and RTCP
  22 // streams.
  23
  24 #ifndef MEDIA_CAST_NET_CAST_TRANSPORT_IMPL_H_
  25 #define MEDIA_CAST_NET_CAST_TRANSPORT_IMPL_H_
  26
  27 #include "base/callback.h"
  28 #include "base/gtest_prod_util.h"
  29 #include "base/memory/ref_counted.h"
  30 #include "base/memory/scoped_ptr.h"
  31 #include "base/memory/weak_ptr.h"
  32 #include "base/time/tick_clock.h"
  33 #include "base/time/time.h"
  34 #include "base/timer/timer.h"
  35 #include "media/cast/common/transport_encryption_handler.h"
  36 #include "media/cast/logging/logging_defines.h"
  37 #include "media/cast/logging/simple_event_subscriber.h"
  38 #include "media/cast/net/cast_transport_config.h"
  39 #include "media/cast/net/cast_transport_sender.h"
  40 #include "media/cast/net/pacing/paced_sender.h"
  41 #include "media/cast/net/rtcp/rtcp.h"
  42 #include "media/cast/net/rtp/rtp_sender.h"
  43
  44 namespace media {
  45 namespace cast {
  46
  47 class UdpTransport;
  48
  49 class CastTransportSenderImpl : public CastTransportSender {
  50  public:
  51   // |external_transport| is only used for testing.
  52   // |raw_events_callback|: Raw events will be returned on this callback
  53   // which will be invoked every |raw_events_callback_interval|.
  54   // This can be a null callback, i.e. if user is not interested in raw events.
  55   // |raw_events_callback_interval|: This can be |base::TimeDelta()| if
  56   // |raw_events_callback| is a null callback.
  57   // |options| contains optional settings for the transport, possible
  58   // keys are:
  59   //   "DSCP" (value ignored) - turns DSCP on
  60   //   "pacer_target_burst_size": int - specifies how many packets to send
  61   //                                    per 10 ms ideally.
  62   //   "pacer_max_burst_size": int - specifies how many pakcets to send
  63   //                                 per 10 ms, max
  64   //   "disable_wifi_scan" (value ignored) - disable wifi scans while streaming
  65   //   "media_streaming_mode" (value ignored) - turn media streaming mode on
  66   // Note, these options may be ignored on some platforms.
  67   CastTransportSenderImpl(
  68       net::NetLog* net_log,
  69       base::TickClock* clock,
  70       const net::IPEndPoint& remote_end_point,
  71       scoped_ptr<base::DictionaryValue> options,
  72       const CastTransportStatusCallback& status_callback,
  73       const BulkRawEventsCallback& raw_events_callback,
  74       base::TimeDelta raw_events_callback_interval,
  75       const scoped_refptr<base::SingleThreadTaskRunner>& transport_task_runner,
  76       PacketSender* external_transport);
  77
  78   virtual ~CastTransportSenderImpl();
  79
  80   virtual void InitializeAudio(const CastTransportRtpConfig& config,
  81                                const RtcpCastMessageCallback& cast_message_cb,
  82                                const RtcpRttCallback& rtt_cb) OVERRIDE;
  83   virtual void InitializeVideo(const CastTransportRtpConfig& config,
  84                                const RtcpCastMessageCallback& cast_message_cb,
  85                                const RtcpRttCallback& rtt_cb) OVERRIDE;
  86   virtual void InsertFrame(uint32 ssrc, const EncodedFrame& frame) OVERRIDE;
  87
  88   virtual void SendSenderReport(
  89       uint32 ssrc,
  90       base::TimeTicks current_time,
  91       uint32 current_time_as_rtp_timestamp) OVERRIDE;
  92
  93   virtual void CancelSendingFrames(
  94       uint32 ssrc,
  95       const std::vector<uint32>& frame_ids) OVERRIDE;
  96
  97   virtual void ResendFrameForKickstart(uint32 ssrc, uint32 frame_id) OVERRIDE;
  98
  99   virtual PacketReceiverCallback PacketReceiverForTesting() OVERRIDE;
 100
 101  private:
 102   FRIEND_TEST_ALL_PREFIXES(CastTransportSenderImplTest, NacksCancelRetransmits);
 103   FRIEND_TEST_ALL_PREFIXES(CastTransportSenderImplTest, CancelRetransmits);
 104   FRIEND_TEST_ALL_PREFIXES(CastTransportSenderImplTest, Kickstart);
 105   FRIEND_TEST_ALL_PREFIXES(CastTransportSenderImplTest,
 106                            DedupRetransmissionWithAudio);
 107
 108   // Resend packets for the stream identified by |ssrc|.
 109   // If |cancel_rtx_if_not_in_list| is true then transmission of packets for the
 110   // frames but not in the list will be dropped.
 111   // See PacedSender::ResendPackets() to see how |dedup_info| works.
 112   void ResendPackets(uint32 ssrc,
 113                      const MissingFramesAndPacketsMap& missing_packets,
 114                      bool cancel_rtx_if_not_in_list,
 115                      const DedupInfo& dedup_info);
 116
 117   // If |raw_events_callback_| is non-null, calls it with events collected
 118   // by |event_subscriber_| since last call.
 119   void SendRawEvents();
 120
 121   // Called when a packet is received.
 122   void OnReceivedPacket(scoped_ptr<Packet> packet);
 123
 124   // Called when a log message is received.
 125   void OnReceivedLogMessage(EventMediaType media_type,
 126                             const RtcpReceiverLogMessage& log);
 127
 128   // Called when a RTCP Cast message is received.
 129   void OnReceivedCastMessage(uint32 ssrc,
 130                              const RtcpCastMessageCallback& cast_message_cb,
 131                              const RtcpCastMessage& cast_message);
 132
 133   base::TickClock* clock_;  // Not owned by this class.
 134   CastTransportStatusCallback status_callback_;
 135   scoped_refptr<base::SingleThreadTaskRunner> transport_task_runner_;
 136
 137   LoggingImpl logging_;
 138
 139   // Interface to a UDP socket.
 140   scoped_ptr<UdpTransport> transport_;
 141
 142   // Packet sender that performs pacing.
 143   PacedSender pacer_;
 144
 145   // Packetizer for audio and video frames.
 146   scoped_ptr<RtpSender> audio_sender_;
 147   scoped_ptr<RtpSender> video_sender_;
 148
 149   // Maintains RTCP session for audio and video.
 150   scoped_ptr<Rtcp> audio_rtcp_session_;
 151   scoped_ptr<Rtcp> video_rtcp_session_;
 152
 153   // Encrypts data in EncodedFrames before they are sent.  Note that it's
 154   // important for the encryption to happen here, in code that would execute in
 155   // the main browser process, for security reasons.  This helps to mitigate
 156   // the damage that could be caused by a compromised renderer process.
 157   TransportEncryptionHandler audio_encryptor_;
 158   TransportEncryptionHandler video_encryptor_;
 159
 160   // This is non-null iff |raw_events_callback_| is non-null.
 161   scoped_ptr<SimpleEventSubscriber> event_subscriber_;
 162
 163   BulkRawEventsCallback raw_events_callback_;
 164   base::TimeDelta raw_events_callback_interval_;
 165
 166   // Right after a frame is sent we record the number of bytes sent to the
 167   // socket. We record the corresponding bytes sent for the most recent ACKed
 168   // audio packet.
 169   int64 last_byte_acked_for_audio_;
 170
 171   scoped_ptr<net::ScopedWifiOptions> wifi_options_autoreset_;
 172
 173   base::WeakPtrFactory<CastTransportSenderImpl> weak_factory_;
 174
 175   DISALLOW_COPY_AND_ASSIGN(CastTransportSenderImpl);
 176 };
 177
 178 }  // namespace cast
 179 }  // namespace media
 180
 181 #endif  // MEDIA_CAST_NET_CAST_TRANSPORT_IMPL_H_