Add extra log when CHLO is considered not fit in one packet.

net/quic/quic_packet_creator.cc

 // Copyright (c) 2012 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_packet_creator.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/macros.h"
@@ skipping 156 matching lines @@
   }
   CreateStreamFrame(id, iov, iov_offset, offset, fin, frame);
   // Explicitly disallow multi-packet CHLOs.
   if (FLAGS_quic_disallow_multi_packet_chlo && id == kCryptoStreamId &&
       frame->stream_frame->data_length >= sizeof(kCHLO) &&
       strncmp(frame->stream_frame->data_buffer,
               reinterpret_cast<const char*>(&kCHLO), sizeof(kCHLO)) == 0) {
     DCHECK_EQ(static_cast<size_t>(0), iov_offset);
     if (frame->stream_frame->data_length < iov.iov->iov_len) {
       const string error_details = "Client hello won't fit in a single packet.";
-      QUIC_BUG << error_details;
+      QUIC_BUG << error_details << " Constructed stream frame length: "
+               << frame->stream_frame->data_length
+               << " CHLO length: " << iov.iov->iov_len;
       delegate_->OnUnrecoverableError(QUIC_CRYPTO_CHLO_TOO_LARGE, error_details,
                                       ConnectionCloseSource::FROM_SELF);
       delete frame->stream_frame;
       return false;
     }
   }
   if (!AddFrame(*frame, /*save_retransmittable_frames=*/true)) {
     // Fails if we try to write unencrypted stream data.
     delete frame->stream_frame;
     return false;
@@ skipping 441 matching lines @@
   // Switching path needs to update packet number length.
   UpdatePacketNumberLength(least_packet_awaited_by_peer, max_packets_in_flight);
 }
 
 bool QuicPacketCreator::IncludeNonceInPublicHeader() {
   return have_diversification_nonce_ &&
          packet_.encryption_level == ENCRYPTION_INITIAL;
 }
 
 }  // namespace net