net/quic/quic_ack_notifier_manager.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_QUIC_QUIC_ACK_NOTIFIER_MANAGER_H_
   6 #define NET_QUIC_QUIC_ACK_NOTIFIER_MANAGER_H_
   7
   8 #include <list>
   9 #include <map>
  10
  11 #include "base/containers/hash_tables.h"
  12 #include "net/quic/quic_protocol.h"
  13
  14 namespace net {
  15
  16 class QuicAckNotifier;
  17
  18 // The AckNotifierManager is used by the QuicSentPacketManager to keep track of
  19 // all the AckNotifiers currently active. It owns the AckNotifiers which it gets
  20 // from the serialized packets passed into OnSerializedPacket. It maintains both
  21 // a set of AckNotifiers and a map from sequence number to AckNotifier the sake
  22 // of efficiency - we can quickly check the map to see if any AckNotifiers are
  23 // interested in a given sequence number.
  24 class NET_EXPORT_PRIVATE AckNotifierManager {
  25  public:
  26   AckNotifierManager();
  27   virtual ~AckNotifierManager();
  28
  29   // Called when the connection receives a new AckFrame.  If |sequence_number|
  30   // exists in ack_notifier_map_ then the corresponding AckNotifiers will have
  31   // their OnAck method called.
  32   void OnPacketAcked(QuicPacketSequenceNumber sequence_number,
  33                      QuicTime::Delta delta_largest_observed);
  34
  35   // If a packet has been retransmitted with a new sequence number, then this
  36   // will be called. It updates the mapping in ack_notifier_map_, and also
  37   // updates the internal set of sequence numbers in each matching AckNotifier.
  38   void OnPacketRetransmitted(QuicPacketSequenceNumber old_sequence_number,
  39                              QuicPacketSequenceNumber new_sequence_number,
  40                              int packet_payload_size);
  41
  42   // This is called after a packet has been serialized, is ready to be sent, and
  43   // contains retransmittable frames (which may have associated AckNotifiers).
  44   // If any of the retransmittable frames included in |serialized_packet| have
  45   // AckNotifiers registered, then add them to our internal map and additionally
  46   // inform the AckNotifier of the sequence number which it should track.
  47   void OnSerializedPacket(const SerializedPacket& serialized_packet);
  48
  49  private:
  50   typedef std::list<QuicAckNotifier*> AckNotifierList;
  51   // TODO(ianswett): Further improvement may come from changing this to a deque.
  52   typedef base::hash_map<QuicPacketSequenceNumber, AckNotifierList>
  53       AckNotifierMap;
  54
  55   // Maps from sequence number to the AckNotifiers which are registered
  56   // for that sequence number. On receipt of an ACK for a given sequence
  57   // number, call OnAck for all mapped AckNotifiers.
  58   // When the last reference is removed from the map, the notifier is deleted.
  59   AckNotifierMap ack_notifier_map_;
  60
  61   DISALLOW_COPY_AND_ASSIGN(AckNotifierManager);
  62 };
  63
  64 }  // namespace net
  65
  66 #endif  // NET_QUIC_QUIC_ACK_NOTIFIER_MANAGER_H_