Landing Recent QUIC Changes.

net/quic/congestion_control/tcp_loss_algorithm.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.
 
 #include "net/quic/congestion_control/tcp_loss_algorithm.h"
 
 #include "net/quic/congestion_control/rtt_stats.h"
 #include "net/quic/quic_protocol.h"
 
 namespace net {
@@ skipping 19 matching lines @@
 // Uses nack counts to decide when packets are lost.
 SequenceNumberSet TCPLossAlgorithm::DetectLostPackets(
     const QuicUnackedPacketMap& unacked_packets,
     const QuicTime& time,
     QuicPacketSequenceNumber largest_observed,
     const RttStats& rtt_stats) {
   SequenceNumberSet lost_packets;
   loss_detection_timeout_ = QuicTime::Zero();
   QuicTime::Delta loss_delay =
       rtt_stats.SmoothedRtt().Multiply(kEarlyRetransmitLossDelayMultiplier);
-
+  QuicPacketSequenceNumber sequence_number = unacked_packets.GetLeastUnacked();
   for (QuicUnackedPacketMap::const_iterator it = unacked_packets.begin();
-       it != unacked_packets.end() && it->first <= largest_observed; ++it) {
-    if (!it->second.in_flight) {
+       it != unacked_packets.end() && sequence_number <= largest_observed;
+       ++it, ++sequence_number) {
+    if (!it->in_flight) {
       continue;
     }
 
-    LOG_IF(DFATAL, it->second.nack_count == 0)
+    LOG_IF(DFATAL, it->nack_count == 0)
         << "All packets less than largest observed should have been nacked.";
-    if (it->second.nack_count >= kNumberOfNacksBeforeRetransmission) {
-      lost_packets.insert(it->first);
+    if (it->nack_count >= kNumberOfNacksBeforeRetransmission) {
+      lost_packets.insert(sequence_number);
       continue;
     }
 
     // Only early retransmit(RFC5827) when the last packet gets acked and
     // there are retransmittable packets in flight.
     // This also implements a timer-protected variant of FACK.
-    if (it->second.retransmittable_frames &&
+    if (it->retransmittable_frames &&
         unacked_packets.largest_sent_packet() == largest_observed) {
       // Early retransmit marks the packet as lost once 1.25RTTs have passed
       // since the packet was sent and otherwise sets an alarm.
-      if (time >= it->second.sent_time.Add(loss_delay)) {
-        lost_packets.insert(it->first);
+      if (time >= it->sent_time.Add(loss_delay)) {
+        lost_packets.insert(sequence_number);
       } else {
         // Set the timeout for the earliest retransmittable packet where early
         // retransmit applies.
-        loss_detection_timeout_ = it->second.sent_time.Add(loss_delay);
+        loss_detection_timeout_ = it->sent_time.Add(loss_delay);
         break;
       }
     }
   }
 
   return lost_packets;
 }
 
 QuicTime TCPLossAlgorithm::GetLossTimeout() const {
   return loss_detection_timeout_;
 }
 
 }  // namespace net