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 namespace test {
  19 class AckNotifierManagerPeer;
  20 }
  21
  22 // The AckNotifierManager is used by the QuicSentPacketManager to keep track of
  23 // all the AckNotifiers currently active. It owns the AckNotifiers which it gets
  24 // from the serialized packets passed into OnSerializedPacket. It maintains both
  25 // a set of AckNotifiers and a map from sequence number to AckNotifier the sake
  26 // of efficiency - we can quickly check the map to see if any AckNotifiers are
  27 // interested in a given sequence number.
  28 class NET_EXPORT_PRIVATE AckNotifierManager {
  29  public:
  30   AckNotifierManager();
  31   virtual ~AckNotifierManager();
  32
  33   // Called when the connection receives a new AckFrame.  If |sequence_number|
  34   // exists in ack_notifier_map_ then the corresponding AckNotifiers will have
  35   // their OnAck method called.
  36   void OnPacketAcked(QuicPacketSequenceNumber sequence_number,
  37                      QuicTime::Delta delta_largest_observed);
  38
  39   // If a packet has been retransmitted with a new sequence number, then this
  40   // will be called. It updates the mapping in ack_notifier_map_, and also
  41   // updates the internal set of sequence numbers in each matching AckNotifier.
  42   void OnPacketRetransmitted(QuicPacketSequenceNumber old_sequence_number,
  43                              QuicPacketSequenceNumber new_sequence_number,
  44                              int packet_payload_size);
  45
  46   // This is called after a packet has been serialized, is ready to be sent, and
  47   // contains retransmittable frames (which may have associated AckNotifiers).
  48   // If any of the retransmittable frames included in |serialized_packet| have
  49   // AckNotifiers registered, then add them to our internal map and additionally
  50   // inform the AckNotifier of the sequence number which it should track.
  51   void OnSerializedPacket(const SerializedPacket& serialized_packet);
  52
  53   // This method is invoked when a packet is removed from the list of unacked
  54   // packets, and it is no longer necessary to keep track of the notifier.
  55   void OnPacketRemoved(QuicPacketSequenceNumber sequence_number);
  56
  57  private:
  58   friend class test::AckNotifierManagerPeer;
  59
  60   typedef std::list<QuicAckNotifier*> AckNotifierList;
  61   // TODO(ianswett): Further improvement may come from changing this to a deque.
  62   typedef base::hash_map<QuicPacketSequenceNumber, AckNotifierList>
  63       AckNotifierMap;
  64
  65   // Maps from sequence number to the AckNotifiers which are registered
  66   // for that sequence number. On receipt of an ACK for a given sequence
  67   // number, call OnAck for all mapped AckNotifiers.
  68   // When the last reference is removed from the map, the notifier is deleted.
  69   AckNotifierMap ack_notifier_map_;
  70
  71   DISALLOW_COPY_AND_ASSIGN(AckNotifierManager);
  72 };
  73
  74 }  // namespace net
  75
  76 #endif  // NET_QUIC_QUIC_ACK_NOTIFIER_MANAGER_H_