Switch to PacketNumberQueue interval iteration and avoid allocations in new ACK frame generation. G…

net/quic/quic_protocol.h

 // 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.
 
 #ifndef NET_QUIC_QUIC_PROTOCOL_H_
 #define NET_QUIC_QUIC_PROTOCOL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 876 matching lines @@
   QuicPacketEntropyHash entropy_hash;
   // The lowest packet we've sent which is unacked, and we expect an ack for.
   QuicPacketNumber least_unacked;
 };
 
 // A sequence of packet numbers where each number is unique. Intended to be used
 // in a sliding window fashion, where smaller old packet numbers are removed and
 // larger new packet numbers are added, with the occasional random access.
 class NET_EXPORT_PRIVATE PacketNumberQueue {
  public:
+  using const_interval_iterator = IntervalSet<QuicPacketNumber>::const_iterator;
+  using const_reverse_interval_iterator =
+      IntervalSet<QuicPacketNumber>::const_reverse_iterator;
   // TODO(jdorfman): remove const_iterator and change the callers to iterate
   // over the intervals.
   class NET_EXPORT_PRIVATE const_iterator
       : public std::iterator<std::input_iterator_tag,
                              QuicPacketNumber,
                              std::ptrdiff_t,
                              const QuicPacketNumber*,
                              const QuicPacketNumber&> {
    public:
     const_iterator(
@@ skipping 79 matching lines @@
 
   // Returns iterators over the individual packet numbers.
   const_iterator begin() const;
   const_iterator end() const;
   const_iterator lower_bound(QuicPacketNumber packet_number) const;
 
   NET_EXPORT_PRIVATE friend std::ostream& operator<<(
       std::ostream& os,
       const PacketNumberQueue& q);
 
+  // Returns iterators over the packet number intervals.
+  const_interval_iterator begin_intervals() const;
+  const_interval_iterator end_intervals() const;
+  const_reverse_interval_iterator rbegin_intervals() const;
+  const_reverse_interval_iterator rend_intervals() const;
+
  private:
   IntervalSet<QuicPacketNumber> packet_number_intervals_;
 };
 
 struct NET_EXPORT_PRIVATE QuicAckFrame {
   QuicAckFrame();
   QuicAckFrame(const QuicAckFrame& other);
   ~QuicAckFrame();
 
   NET_EXPORT_PRIVATE friend std::ostream& operator<<(std::ostream& os,
@@ skipping 491 matching lines @@
       : iov(iov), iov_count(iov_count), total_length(total_length) {}
 
   const struct iovec* iov;
   const int iov_count;
   const size_t total_length;
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_PROTOCOL_H_