Cast: Reject old RTCP packets

media/cast/sender/congestion_control.cc

 // Copyright 2014 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.
 
 // The purpose of this file is determine what bitrate to use for mirroring.
 // Ideally this should be as much as possible, without causing any frames to
 // arrive late.
 
 // The current algorithm is to measure how much bandwidth we've been using
 // recently. We also keep track of how much data has been queued up for sending
@@ skipping 95 matching lines @@
   if (offset < 0 || offset >= static_cast<int32>(frame_stats_.size())) {
     return NULL;
   }
   return &frame_stats_[offset];
 }
 
 void CongestionControl::AckFrame(uint32 frame_id, base::TimeTicks when) {
   FrameStats* frame_stats = GetFrameStats(last_acked_frame_);
   while (IsNewerFrameId(frame_id, last_acked_frame_)) {
     FrameStats* last_frame_stats = frame_stats;
+    frame_stats = GetFrameStats(last_acked_frame_ + 1);

[Alpha Left Google, 2014/08/19 18:01:36]

Why this change? This isn't listed in the CL description.

[hubbe, 2014/08/19 18:27:16]

Because the test I added exposed this bug.
I'll add it to the CL description.

+    DCHECK(frame_stats);
+    if (frame_stats->sent_time.is_null()) {
+      // Can't ack a frame that hasn't been sent yet.
+      return;
+    }
     last_acked_frame_++;
-    frame_stats = GetFrameStats(last_acked_frame_);
-    DCHECK(frame_stats);
+    if (when < frame_stats->sent_time)
+      when = frame_stats->sent_time;
+
     frame_stats->ack_time = when;
     acked_bits_in_history_ += frame_stats->frame_size;
     dead_time_in_history_ += DeadTime(*last_frame_stats, *frame_stats);
   }
 }
 
 void CongestionControl::SendFrameToTransport(uint32 frame_id,
                                              size_t frame_size,
                                              base::TimeTicks when) {
   last_encoded_frame_ = frame_id;
@@ skipping 59 matching lines @@
   VLOG(3) << " FBR:" << (bits_per_second / 1E6)
           << " EBF:" << empty_buffer_fraction
           << " SBR:" << (safe_bitrate / 1E6);
   bits_per_second = std::max(bits_per_second, min_bitrate_configured_);
   bits_per_second = std::min(bits_per_second, max_bitrate_configured_);
   return bits_per_second;
 }
 
 }  // namespace cast
 }  // namespace media