• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 #include "net/quic/quic_ack_notifier_manager.h"
6 
7 #include <stddef.h>
8 #include <list>
9 #include <map>
10 #include <utility>
11 #include <vector>
12 
13 #include "base/stl_util.h"
14 #include "net/quic/quic_ack_notifier.h"
15 #include "net/quic/quic_protocol.h"
16 
17 namespace net {
18 
AckNotifierManager()19 AckNotifierManager::AckNotifierManager() {}
20 
~AckNotifierManager()21 AckNotifierManager::~AckNotifierManager() {
22   STLDeleteElements(&ack_notifiers_);
23 }
24 
OnPacketAcked(QuicPacketSequenceNumber sequence_number)25 void AckNotifierManager::OnPacketAcked(
26     QuicPacketSequenceNumber sequence_number) {
27   // Inform all the registered AckNotifiers of the new ACK.
28   AckNotifierMap::iterator map_it = ack_notifier_map_.find(sequence_number);
29   if (map_it == ack_notifier_map_.end()) {
30     // No AckNotifier is interested in this sequence number.
31     return;
32   }
33 
34   // One or more AckNotifiers are registered as interested in this sequence
35   // number. Iterate through them and call OnAck on each.
36   for (AckNotifierSet::iterator set_it = map_it->second.begin();
37        set_it != map_it->second.end(); ++set_it) {
38     QuicAckNotifier* ack_notifier = *set_it;
39     ack_notifier->OnAck(sequence_number);
40 
41     // If this has resulted in an empty AckNotifer, erase it.
42     if (ack_notifier->IsEmpty()) {
43       delete ack_notifier;
44       ack_notifiers_.erase(ack_notifier);
45     }
46   }
47 
48   // Remove the sequence number from the map as we have notified all the
49   // registered AckNotifiers, and we won't see it again.
50   ack_notifier_map_.erase(map_it);
51 }
52 
UpdateSequenceNumber(QuicPacketSequenceNumber old_sequence_number,QuicPacketSequenceNumber new_sequence_number)53 void AckNotifierManager::UpdateSequenceNumber(
54     QuicPacketSequenceNumber old_sequence_number,
55     QuicPacketSequenceNumber new_sequence_number) {
56   AckNotifierMap::iterator map_it = ack_notifier_map_.find(old_sequence_number);
57   if (map_it != ack_notifier_map_.end()) {
58     // We will add an entry to the map for the new sequence number, and move
59     // the
60     // list of AckNotifiers over.
61     AckNotifierSet new_set;
62     for (AckNotifierSet::iterator notifier_it = map_it->second.begin();
63          notifier_it != map_it->second.end(); ++notifier_it) {
64       (*notifier_it)
65           ->UpdateSequenceNumber(old_sequence_number, new_sequence_number);
66       new_set.insert(*notifier_it);
67     }
68     ack_notifier_map_[new_sequence_number] = new_set;
69     ack_notifier_map_.erase(map_it);
70   }
71 }
72 
OnSerializedPacket(const SerializedPacket & serialized_packet)73 void AckNotifierManager::OnSerializedPacket(
74     const SerializedPacket& serialized_packet) {
75   // Run through all the frames and if any of them are stream frames and have
76   // an AckNotifier registered, then inform the AckNotifier that it should be
77   // interested in this packet's sequence number.
78 
79   RetransmittableFrames* frames = serialized_packet.retransmittable_frames;
80 
81   // AckNotifiers can only be attached to retransmittable frames.
82   if (!frames) {
83     return;
84   }
85 
86   for (QuicFrames::const_iterator it = frames->frames().begin();
87        it != frames->frames().end(); ++it) {
88     if (it->type == STREAM_FRAME && it->stream_frame->notifier != NULL) {
89       QuicAckNotifier* notifier = it->stream_frame->notifier;
90 
91       // The AckNotifier needs to know it is tracking this packet's sequence
92       // number.
93       notifier->AddSequenceNumber(serialized_packet.sequence_number);
94 
95       // Update the mapping in the other direction, from sequence
96       // number to AckNotifier.
97       ack_notifier_map_[serialized_packet.sequence_number].insert(notifier);
98 
99       // Take ownership of the AckNotifier.
100       ack_notifiers_.insert(notifier);
101     }
102   }
103 }
104 
105 }  // namespace net
106