Change TransmissionInfo's all_transmissions SequenceNumberSet* to

net/quic/quic_unacked_packet_map.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/quic_unacked_packet_map.h"
 
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "net/quic/quic_connection_stats.h"
 #include "net/quic/quic_utils_chromium.h"
 
 using std::max;
 
 namespace net {
 
 QuicUnackedPacketMap::QuicUnackedPacketMap()
     : largest_sent_packet_(0),
       largest_observed_(0),
       least_unacked_(1),
       bytes_in_flight_(0),
       pending_crypto_packet_count_(0) {
 }
 
 QuicUnackedPacketMap::~QuicUnackedPacketMap() {
   QuicPacketSequenceNumber index = least_unacked_;
   for (UnackedPacketMap::iterator it = unacked_packets_.begin();
        it != unacked_packets_.end(); ++it, ++index) {
     delete it->retransmittable_frames;
     // Only delete all_transmissions once, for the newest packet.
-    if (index == *it->all_transmissions->rbegin()) {
+    if (it->all_transmissions != NULL &&
+        index == *it->all_transmissions->rbegin()) {
       delete it->all_transmissions;
     }
   }
 }
 
 // TODO(ianswett): Combine this method with OnPacketSent once packets are always
 // sent in order and the connection tracks RetransmittableFrames for longer.
 void QuicUnackedPacketMap::AddPacket(
     const SerializedPacket& serialized_packet) {
   DCHECK_EQ(least_unacked_ + unacked_packets_.size(),
             serialized_packet.sequence_number);
   unacked_packets_.push_back(
       TransmissionInfo(serialized_packet.retransmittable_frames,
-                       serialized_packet.sequence_number,
                        serialized_packet.sequence_number_length));
   if (serialized_packet.retransmittable_frames != NULL &&
       serialized_packet.retransmittable_frames->HasCryptoHandshake()
           == IS_HANDSHAKE) {
     ++pending_crypto_packet_count_;
   }
 }
 
 void QuicUnackedPacketMap::RemoveObsoletePackets() {
   while (!unacked_packets_.empty()) {
@@ skipping 20 matching lines @@
   RetransmittableFrames* frames = transmission_info->retransmittable_frames;
   LOG_IF(DFATAL, frames == NULL) << "Attempt to retransmit packet with no "
                                  << "retransmittable frames: "
                                  << old_sequence_number;
 
   // We keep the old packet in the unacked packet list until it, or one of
   // the retransmissions of it are acked.
   transmission_info->retransmittable_frames = NULL;
   // Only keep one transmission older than largest observed, because only the
   // most recent is expected to possibly be a spurious retransmission.
-  if (transmission_info->all_transmissions->size() > 1 &&
+  if (transmission_info->all_transmissions != NULL &&
       *(++transmission_info->all_transmissions->begin()) < largest_observed_) {
     QuicPacketSequenceNumber old_transmission =
         *transmission_info->all_transmissions->begin();
     TransmissionInfo* old_info =
         &unacked_packets_[old_transmission - least_unacked_];
     // Don't remove old packets if they're still in flight.
     if (!old_info->in_flight) {
-      transmission_info->all_transmissions->erase(old_transmission);
+      old_info->all_transmissions->pop_front();
       // This will cause the packet be removed in RemoveObsoletePackets.
-      old_info->all_transmissions = new SequenceNumberSet();
-      old_info->all_transmissions->insert(old_transmission);
+      old_info->all_transmissions = NULL;
     }
   }
+  if (transmission_info->all_transmissions == NULL) {
+    transmission_info->all_transmissions = new SequenceNumberList();
+    transmission_info->all_transmissions->push_back(old_sequence_number);
+  }
+  transmission_info->all_transmissions->push_back(new_sequence_number);
   unacked_packets_.push_back(
       TransmissionInfo(frames,
-                       new_sequence_number,
                        transmission_info->sequence_number_length,
                        transmission_type,
                        transmission_info->all_transmissions));
 }
 
 void QuicUnackedPacketMap::ClearPreviousRetransmissions(size_t num_to_clear) {
   while (!unacked_packets_.empty() && num_to_clear > 0) {
     // If this packet is in flight, or has retransmittable data, then there is
     // no point in clearing out any further packets, because they would not
     // affect the high water mark.
     TransmissionInfo* info = &unacked_packets_.front();
     if (info->in_flight || info->retransmittable_frames != NULL) {
       break;
     }
 
-    info->all_transmissions->erase(least_unacked_);
+    info->all_transmissions->pop_front();
     LOG_IF(DFATAL, info->all_transmissions->empty())
         << "Previous retransmissions must have a newer transmission.";
     unacked_packets_.pop_front();
     ++least_unacked_;
     --num_to_clear;
   }
 }
 
 bool QuicUnackedPacketMap::HasRetransmittableFrames(
     QuicPacketSequenceNumber sequence_number) const {
@@ skipping 10 matching lines @@
   unacked_packets_[sequence_number - least_unacked_].nack_count =
       max(min_nacks,
           unacked_packets_[sequence_number - least_unacked_].nack_count);
 }
 
 void QuicUnackedPacketMap::RemoveRetransmittability(
     QuicPacketSequenceNumber sequence_number) {
   DCHECK_GE(sequence_number, least_unacked_);
   DCHECK_LT(sequence_number, least_unacked_ + unacked_packets_.size());
   TransmissionInfo* info = &unacked_packets_[sequence_number - least_unacked_];
-  SequenceNumberSet* all_transmissions = info->all_transmissions;
-  if (all_transmissions->size() == 1) {
+  SequenceNumberList* all_transmissions = info->all_transmissions;
+  if (all_transmissions == NULL) {
     MaybeRemoveRetransmittableFrames(info);
     return;
   }
   // TODO(ianswett): Consider adding a check to ensure there are retransmittable
   // frames associated with this packet.
-  for (SequenceNumberSet::const_iterator it = all_transmissions->begin();
+  for (SequenceNumberList::const_iterator it = all_transmissions->begin();
        it != all_transmissions->end(); ++it) {
     TransmissionInfo* transmission_info =
         &unacked_packets_[*it - least_unacked_];
     MaybeRemoveRetransmittableFrames(transmission_info);
-    transmission_info->all_transmissions = new SequenceNumberSet();
-    transmission_info->all_transmissions->insert(*it);
+    transmission_info->all_transmissions = NULL;
   }
   delete all_transmissions;
 }
 
 void QuicUnackedPacketMap::MaybeRemoveRetransmittableFrames(
     TransmissionInfo* transmission_info) {
   if (transmission_info->retransmittable_frames != NULL) {
     if (transmission_info->retransmittable_frames->HasCryptoHandshake()
             == IS_HANDSHAKE) {
       --pending_crypto_packet_count_;
     }
     delete transmission_info->retransmittable_frames;
     transmission_info->retransmittable_frames = NULL;
   }
 }
 
 void QuicUnackedPacketMap::IncreaseLargestObserved(
     QuicPacketSequenceNumber largest_observed) {
   DCHECK_LE(largest_observed_, largest_observed);
   largest_observed_ = largest_observed;
 }
 
 bool QuicUnackedPacketMap::IsPacketUseless(
     QuicPacketSequenceNumber sequence_number,
     const TransmissionInfo& info) const {
   return sequence_number <= largest_observed_ &&
       !info.in_flight &&
       info.retransmittable_frames == NULL &&
-      info.all_transmissions->size() == 1;
+      info.all_transmissions == NULL;
 }
 
 bool QuicUnackedPacketMap::IsUnacked(
     QuicPacketSequenceNumber sequence_number) const {
   if (sequence_number < least_unacked_ ||
       sequence_number >= least_unacked_ + unacked_packets_.size()) {
     return false;
   }
   return !IsPacketUseless(sequence_number,
                           unacked_packets_[sequence_number - least_unacked_]);
@@ skipping 125 matching lines @@
   TransmissionInfo* info = &unacked_packets_[sequence_number - least_unacked_];
   DCHECK(!info->in_flight);
   DCHECK_NE(0u, info->bytes_sent);
   DCHECK(info->sent_time.IsInitialized());
 
   bytes_in_flight_ += info->bytes_sent;
   info->in_flight = true;
 }
 
 }  // namespace net