Move common code and variables from audio/video sender to frame sender.

More cleanup to come.

BUG=406622

Review URL: https://codereview.chromium.org/514263002

Cr-Commit-Position: refs/heads/master@{#292496}

6 files changed, 90 insertions, 179 deletions

diff --git a/media/cast/sender/audio_sender.cc b/media/cast/sender/audio_sender.cc
index 4bf93b3..040bc62 100644
--- a/media/cast/sender/audio_sender.cc
+++ b/media/cast/sender/audio_sender.cc
@@ -16,7 +16,6 @@ namespace cast {
 namespace {
 
 const int kNumAggressiveReportsSentAtStart = 100;
-const int kMinSchedulingDelayMs = 1;
 
 // TODO(miu): This should be specified in AudioSenderConfig, but currently it is
 // fixed to 100 FPS (i.e., 10 ms per frame), and AudioEncoder assumes this as
@@ -37,12 +36,8 @@ AudioSender::AudioSender(scoped_refptr<CastEnvironment> cast_environment,
         kAudioFrameRate * 2.0, // We lie to increase max outstanding frames.
         audio_config.target_playout_delay),
       configured_encoder_bitrate_(audio_config.bitrate),
-      num_aggressive_rtcp_reports_sent_(0),
-      last_sent_frame_id_(0),
-      latest_acked_frame_id_(0),
-      duplicate_ack_counter_(0),
-      cast_initialization_status_(STATUS_AUDIO_UNINITIALIZED),
       weak_factory_(this) {
+  cast_initialization_status_ = STATUS_AUDIO_UNINITIALIZED;
   VLOG(1) << "max_unacked_frames " << max_unacked_frames_;
   DCHECK_GT(max_unacked_frames_, 0);
 
@@ -76,7 +71,6 @@ AudioSender::AudioSender(scoped_refptr<CastEnvironment> cast_environment,
       base::Bind(&AudioSender::OnReceivedCastFeedback,
                  weak_factory_.GetWeakPtr()),
       base::Bind(&AudioSender::OnReceivedRtt, weak_factory_.GetWeakPtr()));
-  memset(frame_id_to_rtp_timestamp_, 0, sizeof(frame_id_to_rtp_timestamp_));
 }
 
 AudioSender::~AudioSender() {}
@@ -149,37 +143,6 @@ void AudioSender::SendEncodedAudioFrame(
   transport_sender_->InsertCodedAudioFrame(*encoded_frame);
 }
 
-void AudioSender::ScheduleNextResendCheck() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  DCHECK(!last_send_time_.is_null());
-  base::TimeDelta time_to_next =
-      last_send_time_ - cast_environment_->Clock()->NowTicks() +
-      target_playout_delay_;
-  time_to_next = std::max(
-      time_to_next, base::TimeDelta::FromMilliseconds(kMinSchedulingDelayMs));
-  cast_environment_->PostDelayedTask(
-      CastEnvironment::MAIN,
-      FROM_HERE,
-      base::Bind(&AudioSender::ResendCheck, weak_factory_.GetWeakPtr()),
-      time_to_next);
-}
-
-void AudioSender::ResendCheck() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  DCHECK(!last_send_time_.is_null());
-  const base::TimeDelta time_since_last_send =
-      cast_environment_->Clock()->NowTicks() - last_send_time_;
-  if (time_since_last_send > target_playout_delay_) {
-    if (latest_acked_frame_id_ == last_sent_frame_id_) {
-      // Last frame acked, no point in doing anything
-    } else {
-      VLOG(1) << "ACK timeout; last acked frame: " << latest_acked_frame_id_;
-      ResendForKickstart();
-    }
-  }
-  ScheduleNextResendCheck();
-}
-
 void AudioSender::OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback) {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
 
@@ -257,14 +220,5 @@ bool AudioSender::AreTooManyFramesInFlight() const {
   return frames_in_flight >= max_unacked_frames_;
 }
 
-void AudioSender::ResendForKickstart() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  DCHECK(!last_send_time_.is_null());
-  VLOG(1) << "Resending last packet of frame " << last_sent_frame_id_
-          << " to kick-start.";
-  last_send_time_ = cast_environment_->Clock()->NowTicks();
-  transport_sender_->ResendFrameForKickstart(ssrc_, last_sent_frame_id_);
-}
-
 }  // namespace cast
 }  // namespace media
diff --git a/media/cast/sender/audio_sender.h b/media/cast/sender/audio_sender.h
index e07b892..4ca539b 100644
--- a/media/cast/sender/audio_sender.h
+++ b/media/cast/sender/audio_sender.h
@@ -55,15 +55,6 @@ class AudioSender : public FrameSender,
   void OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback);
 
  private:
-  // Schedule and execute periodic checks for re-sending packets.  If no
-  // acknowledgements have been received for "too long," AudioSender will
-  // speculatively re-send certain packets of an unacked frame to kick-start
-  // re-transmission.  This is a last resort tactic to prevent the session from
-  // getting stuck after a long outage.
-  void ScheduleNextResendCheck();
-  void ResendCheck();
-  void ResendForKickstart();
-
   // Returns true if there are too many frames in flight, as defined by the
   // configured target playout delay plus simple logic.  When this is true,
   // InsertAudio() will silenty drop frames instead of sending them to the audio
@@ -77,39 +68,6 @@ class AudioSender : public FrameSender,
   scoped_ptr<AudioEncoder> audio_encoder_;
   const int configured_encoder_bitrate_;
 
-  // Counts how many RTCP reports are being "aggressively" sent (i.e., one per
-  // frame) at the start of the session.  Once a threshold is reached, RTCP
-  // reports are instead sent at the configured interval + random drift.
-  int num_aggressive_rtcp_reports_sent_;
-
-  // This is "null" until the first frame is sent.  Thereafter, this tracks the
-  // last time any frame was sent or re-sent.
-  base::TimeTicks last_send_time_;
-
-  // The ID of the last frame sent.  Logic throughout AudioSender assumes this
-  // can safely wrap-around.  This member is invalid until
-  // |!last_send_time_.is_null()|.
-  uint32 last_sent_frame_id_;
-
-  // The ID of the latest (not necessarily the last) frame that has been
-  // acknowledged.  Logic throughout AudioSender assumes this can safely
-  // wrap-around.  This member is invalid until |!last_send_time_.is_null()|.
-  uint32 latest_acked_frame_id_;
-
-  // Counts the number of duplicate ACK that are being received.  When this
-  // number reaches a threshold, the sender will take this as a sign that the
-  // receiver hasn't yet received the first packet of the next frame.  In this
-  // case, AudioSender will trigger a re-send of the next frame.
-  int duplicate_ack_counter_;
-
-  // If this sender is ready for use, this is STATUS_AUDIO_INITIALIZED.
-  CastInitializationStatus cast_initialization_status_;
-
-  // This is a "good enough" mapping for finding the RTP timestamp associated
-  // with a video frame. The key is the lowest 8 bits of frame id (which is
-  // what is sent via RTCP). This map is used for logging purposes.
-  RtpTimestamp frame_id_to_rtp_timestamp_[256];
-
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<AudioSender> weak_factory_;
 
diff --git a/media/cast/sender/frame_sender.cc b/media/cast/sender/frame_sender.cc
index b531a06..61f8b1a 100644
--- a/media/cast/sender/frame_sender.cc
+++ b/media/cast/sender/frame_sender.cc
@@ -24,9 +24,14 @@ FrameSender::FrameSender(scoped_refptr<CastEnvironment> cast_environment,
       rtt_available_(false),
       rtcp_interval_(rtcp_interval),
       max_frame_rate_(max_frame_rate),
+      num_aggressive_rtcp_reports_sent_(0),
+      last_sent_frame_id_(0),
+      latest_acked_frame_id_(0),
+      duplicate_ack_counter_(0),
       weak_factory_(this) {
   SetTargetPlayoutDelay(playout_delay);
   send_target_playout_delay_ = false;
+  memset(frame_id_to_rtp_timestamp_, 0, sizeof(frame_id_to_rtp_timestamp_));
 }
 
 FrameSender::~FrameSender() {
@@ -84,5 +89,45 @@ void FrameSender::SetTargetPlayoutDelay(
   send_target_playout_delay_ = true;
 }
 
+void FrameSender::ResendCheck() {
+  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
+  DCHECK(!last_send_time_.is_null());
+  const base::TimeDelta time_since_last_send =
+      cast_environment_->Clock()->NowTicks() - last_send_time_;
+  if (time_since_last_send > target_playout_delay_) {
+    if (latest_acked_frame_id_ == last_sent_frame_id_) {
+      // Last frame acked, no point in doing anything
+    } else {
+      VLOG(1) << "ACK timeout; last acked frame: " << latest_acked_frame_id_;
+      ResendForKickstart();
+    }
+  }
+  ScheduleNextResendCheck();
+}
+
+void FrameSender::ScheduleNextResendCheck() {
+  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
+  DCHECK(!last_send_time_.is_null());
+  base::TimeDelta time_to_next =
+      last_send_time_ - cast_environment_->Clock()->NowTicks() +
+      target_playout_delay_;
+  time_to_next = std::max(
+      time_to_next, base::TimeDelta::FromMilliseconds(kMinSchedulingDelayMs));
+  cast_environment_->PostDelayedTask(
+      CastEnvironment::MAIN,
+      FROM_HERE,
+      base::Bind(&FrameSender::ResendCheck, weak_factory_.GetWeakPtr()),
+      time_to_next);
+}
+
+void FrameSender::ResendForKickstart() {
+  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
+  DCHECK(!last_send_time_.is_null());
+  VLOG(1) << "Resending last packet of frame " << last_sent_frame_id_
+          << " to kick-start.";
+  last_send_time_ = cast_environment_->Clock()->NowTicks();
+  transport_sender_->ResendFrameForKickstart(ssrc_, last_sent_frame_id_);
+}
+
 }  // namespace cast
 }  // namespace media
diff --git a/media/cast/sender/frame_sender.h b/media/cast/sender/frame_sender.h
index 5da392796..09211da 100644
--- a/media/cast/sender/frame_sender.h
+++ b/media/cast/sender/frame_sender.h
@@ -74,6 +74,15 @@ class FrameSender {
   base::TimeDelta max_rtt_;
 
  protected:
+  // Schedule and execute periodic checks for re-sending packets.  If no
+  // acknowledgements have been received for "too long," AudioSender will
+  // speculatively re-send certain packets of an unacked frame to kick-start
+  // re-transmission.  This is a last resort tactic to prevent the session from
+  // getting stuck after a long outage.
+  void ScheduleNextResendCheck();
+  void ResendCheck();
+  void ResendForKickstart();
+
   const base::TimeDelta rtcp_interval_;
 
   // The total amount of time between a frame's capture/recording on the sender
@@ -94,6 +103,40 @@ class FrameSender {
   // new frames shall halt.
   int max_unacked_frames_;
 
+  // Counts how many RTCP reports are being "aggressively" sent (i.e., one per
+  // frame) at the start of the session.  Once a threshold is reached, RTCP
+  // reports are instead sent at the configured interval + random drift.
+  int num_aggressive_rtcp_reports_sent_;
+
+  // This is "null" until the first frame is sent.  Thereafter, this tracks the
+  // last time any frame was sent or re-sent.
+  base::TimeTicks last_send_time_;
+
+  // The ID of the last frame sent.  Logic throughout AudioSender assumes this
+  // can safely wrap-around.  This member is invalid until
+  // |!last_send_time_.is_null()|.
+  uint32 last_sent_frame_id_;
+
+  // The ID of the latest (not necessarily the last) frame that has been
+  // acknowledged.  Logic throughout AudioSender assumes this can safely
+  // wrap-around.  This member is invalid until |!last_send_time_.is_null()|.
+  uint32 latest_acked_frame_id_;
+
+  // Counts the number of duplicate ACK that are being received.  When this
+  // number reaches a threshold, the sender will take this as a sign that the
+  // receiver hasn't yet received the first packet of the next frame.  In this
+  // case, VideoSender will trigger a re-send of the next frame.
+  int duplicate_ack_counter_;
+
+  // If this sender is ready for use, this is STATUS_AUDIO_INITIALIZED or
+  // STATUS_VIDEO_INITIALIZED.
+  CastInitializationStatus cast_initialization_status_;
+
+  // This is a "good enough" mapping for finding the RTP timestamp associated
+  // with a video frame. The key is the lowest 8 bits of frame id (which is
+  // what is sent via RTCP). This map is used for logging purposes.
+  RtpTimestamp frame_id_to_rtp_timestamp_[256];
+
  private:
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<FrameSender> weak_factory_;
diff --git a/media/cast/sender/video_sender.cc b/media/cast/sender/video_sender.cc
index f0e3a14..3fc5f6c 100644
--- a/media/cast/sender/video_sender.cc
+++ b/media/cast/sender/video_sender.cc
@@ -20,7 +20,6 @@ namespace media {
 namespace cast {
 
 const int kNumAggressiveReportsSentAtStart = 100;
-const int kMinSchedulingDelayMs = 1;
 
 namespace {
 
@@ -51,17 +50,13 @@ VideoSender::VideoSender(
         video_config.max_frame_rate,
         video_config.target_playout_delay),
       fixed_bitrate_(GetFixedBitrate(video_config)),
-      num_aggressive_rtcp_reports_sent_(0),
       frames_in_encoder_(0),
-      last_sent_frame_id_(0),
-      latest_acked_frame_id_(0),
-      duplicate_ack_counter_(0),
       congestion_control_(cast_environment->Clock(),
                           video_config.max_bitrate,
                           video_config.min_bitrate,
                           max_unacked_frames_),
-      cast_initialization_status_(STATUS_VIDEO_UNINITIALIZED),
       weak_factory_(this) {
+  cast_initialization_status_ = STATUS_VIDEO_UNINITIALIZED;
   VLOG(1) << "max_unacked_frames is " << max_unacked_frames_
           << " for target_playout_delay="
           << target_playout_delay_.InMilliseconds() << " ms"
@@ -92,8 +87,6 @@ VideoSender::VideoSender(
       base::Bind(&VideoSender::OnReceivedCastFeedback,
                  weak_factory_.GetWeakPtr()),
       base::Bind(&VideoSender::OnReceivedRtt, weak_factory_.GetWeakPtr()));
-
-  memset(frame_id_to_rtp_timestamp_, 0, sizeof(frame_id_to_rtp_timestamp_));
 }
 
 VideoSender::~VideoSender() {
@@ -223,37 +216,6 @@ void VideoSender::SendEncodedVideoFrame(
   transport_sender_->InsertCodedVideoFrame(*encoded_frame);
 }
 
-void VideoSender::ResendCheck() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  DCHECK(!last_send_time_.is_null());
-  const base::TimeDelta time_since_last_send =
-      cast_environment_->Clock()->NowTicks() - last_send_time_;
-  if (time_since_last_send > target_playout_delay_) {
-    if (latest_acked_frame_id_ == last_sent_frame_id_) {
-      // Last frame acked, no point in doing anything
-    } else {
-      VLOG(1) << "ACK timeout; last acked frame: " << latest_acked_frame_id_;
-      ResendForKickstart();
-    }
-  }
-  ScheduleNextResendCheck();
-}
-
-void VideoSender::ScheduleNextResendCheck() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  DCHECK(!last_send_time_.is_null());
-  base::TimeDelta time_to_next =
-      last_send_time_ - cast_environment_->Clock()->NowTicks() +
-      target_playout_delay_;
-  time_to_next = std::max(
-      time_to_next, base::TimeDelta::FromMilliseconds(kMinSchedulingDelayMs));
-  cast_environment_->PostDelayedTask(
-      CastEnvironment::MAIN,
-      FROM_HERE,
-      base::Bind(&VideoSender::ResendCheck, weak_factory_.GetWeakPtr()),
-      time_to_next);
-}
-
 void VideoSender::OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback) {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
 
@@ -352,14 +314,5 @@ bool VideoSender::AreTooManyFramesInFlight() const {
   return frames_in_flight >= max_unacked_frames_;
 }
 
-void VideoSender::ResendForKickstart() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  DCHECK(!last_send_time_.is_null());
-  VLOG(1) << "Resending last packet of frame " << last_sent_frame_id_
-          << " to kick-start.";
-  last_send_time_ = cast_environment_->Clock()->NowTicks();
-  transport_sender_->ResendFrameForKickstart(ssrc_, last_sent_frame_id_);
-}
-
 }  // namespace cast
 }  // namespace media
diff --git a/media/cast/sender/video_sender.h b/media/cast/sender/video_sender.h
index ebada4d..5fe3261 100644
--- a/media/cast/sender/video_sender.h
+++ b/media/cast/sender/video_sender.h
@@ -61,15 +61,6 @@ class VideoSender : public FrameSender,
   void OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback);
 
  private:
-  // Schedule and execute periodic checks for re-sending packets.  If no
-  // acknowledgements have been received for "too long," VideoSender will
-  // speculatively re-send certain packets of an unacked frame to kick-start
-  // re-transmission.  This is a last resort tactic to prevent the session from
-  // getting stuck after a long outage.
-  void ScheduleNextResendCheck();
-  void ResendCheck();
-  void ResendForKickstart();
-
   // Returns true if there are too many frames in flight, as defined by the
   // configured target playout delay plus simple logic.  When this is true,
   // InsertRawVideoFrame() will silenty drop frames instead of sending them to
@@ -89,47 +80,14 @@ class VideoSender : public FrameSender,
   // a hardware-based encoder.
   scoped_ptr<VideoEncoder> video_encoder_;
 
-  // Counts how many RTCP reports are being "aggressively" sent (i.e., one per
-  // frame) at the start of the session.  Once a threshold is reached, RTCP
-  // reports are instead sent at the configured interval + random drift.
-  int num_aggressive_rtcp_reports_sent_;
-
   // The number of frames currently being processed in |video_encoder_|.
   int frames_in_encoder_;
 
-  // This is "null" until the first frame is sent.  Thereafter, this tracks the
-  // last time any frame was sent or re-sent.
-  base::TimeTicks last_send_time_;
-
-  // The ID of the last frame sent.  Logic throughout VideoSender assumes this
-  // can safely wrap-around.  This member is invalid until
-  // |!last_send_time_.is_null()|.
-  uint32 last_sent_frame_id_;
-
-  // The ID of the latest (not necessarily the last) frame that has been
-  // acknowledged.  Logic throughout VideoSender assumes this can safely
-  // wrap-around.  This member is invalid until |!last_send_time_.is_null()|.
-  uint32 latest_acked_frame_id_;
-
-  // Counts the number of duplicate ACK that are being received.  When this
-  // number reaches a threshold, the sender will take this as a sign that the
-  // receiver hasn't yet received the first packet of the next frame.  In this
-  // case, VideoSender will trigger a re-send of the next frame.
-  int duplicate_ack_counter_;
-
   // When we get close to the max number of un-acked frames, we set lower
   // the bitrate drastically to ensure that we catch up. Without this we
   // risk getting stuck in a catch-up state forever.
   CongestionControl congestion_control_;
 
-  // If this sender is ready for use, this is STATUS_VIDEO_INITIALIZED.
-  CastInitializationStatus cast_initialization_status_;
-
-  // This is a "good enough" mapping for finding the RTP timestamp associated
-  // with a video frame. The key is the lowest 8 bits of frame id (which is
-  // what is sent via RTCP). This map is used for logging purposes.
-  RtpTimestamp frame_id_to_rtp_timestamp_[256];
-
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<VideoSender> weak_factory_;