Fix the logic for computing the number of truncated QUIC ACK frames sent.

net/quic/quic_connection_logger.cc

 // Copyright (c) 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.
 
 #include "net/quic/quic_connection_logger.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 353 matching lines @@
       break;
     case STREAM_FRAME:
       net_log_.AddEvent(
           NetLog::TYPE_QUIC_SESSION_STREAM_FRAME_SENT,
           base::Bind(&NetLogQuicStreamFrameCallback, frame.stream_frame));
       break;
     case ACK_FRAME:
       net_log_.AddEvent(
           NetLog::TYPE_QUIC_SESSION_ACK_FRAME_SENT,
           base::Bind(&NetLogQuicAckFrameCallback, frame.ack_frame));
-      if (frame.ack_frame->is_truncated)
+      size_t num_ranges = 0;
+      QuicPacketSequenceNumber last_missing = 0;
+      for (size_t i = 0; i < frame.ack_frame->missing_packets.size(); ++i) {
+        if (frame.ack_frame->missing_packets[i] != last_missing + 1) {

[Ian Swett, 2014/09/08 17:27:58]

It's annoying to have to perform this logic in multiple spots, but LGTM.

+          ++num_ranges;
+        }
+        last_missing = frame.ack_frame->missing_packets[i];
+      }
+      if (num_ranges >= numeric_limits<uint8>::max())
         ++num_truncated_acks_sent_;
       break;
     case CONGESTION_FEEDBACK_FRAME:
       net_log_.AddEvent(
           NetLog::TYPE_QUIC_SESSION_CONGESTION_FEEDBACK_FRAME_SENT,
           base::Bind(&NetLogQuicCongestionFeedbackFrameCallback,
                      frame.congestion_feedback_frame));
       break;
     case RST_STREAM_FRAME:
       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicSession.RstStreamErrorCodeClient",
@@ skipping 467 matching lines @@
       continue;
     }
     // Record some overlapping patterns, to get a better picture, since this is
     // not very expensive.
     if (i % 3 == 0)
       six_packet_histogram->Add(recent_6_mask);
   }
 }
 
 }  // namespace net