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_H_ 6 #define NET_QUIC_QUIC_ACK_NOTIFIER_H_ 7 8 #include "base/memory/ref_counted.h" 9 #include "net/quic/quic_protocol.h" 10 11 namespace net { 12 13 // Used to register with a QuicConnection for notification once a set of packets 14 // have all been ACKed. 15 // The connection informs this class of newly ACKed sequence numbers, and once 16 // we have seen ACKs for all the sequence numbers we are interested in, we 17 // trigger a call to a provided Closure. 18 class NET_EXPORT_PRIVATE QuicAckNotifier { 19 public: 20 class NET_EXPORT_PRIVATE DelegateInterface 21 : public base::RefCounted<DelegateInterface> { 22 public: 23 DelegateInterface(); 24 // Args: 25 // num_original_packets - Number of packets in the original transmission. 26 // num_original_bytes - Number of packets in the original transmission. 27 // num_retransmitted_packets - Number of packets that had to be 28 // retransmitted. 29 // num_retransmitted_bytes - Number of bytes that had to be retransmitted. 30 virtual void OnAckNotification(int num_original_packets, 31 int num_original_bytes, 32 int num_retransmitted_packets, 33 int num_retransmitted_bytes, 34 QuicTime::Delta delta_largest_observed) = 0; 35 protected: 36 friend class base::RefCounted<DelegateInterface>; 37 38 // Delegates are ref counted. 39 virtual ~DelegateInterface(); 40 }; 41 42 // QuicAckNotifier is expected to keep its own reference to the delegate. 43 explicit QuicAckNotifier(DelegateInterface* delegate); 44 virtual ~QuicAckNotifier(); 45 46 // Register a sequence number that this AckNotifier should be interested in. 47 void AddSequenceNumber(const QuicPacketSequenceNumber& sequence_number, 48 int packet_payload_size); 49 50 // Called by the QuicConnection on receipt of new ACK frame, with the sequence 51 // number referenced by the ACK frame. 52 // Deletes the matching sequence number from the stored set of sequence 53 // numbers. If this set is now empty, call the stored delegate's 54 // OnAckNotification method. 55 // 56 // Returns true if the provided sequence_number caused the delegate to be 57 // called, false otherwise. 58 bool OnAck(QuicPacketSequenceNumber sequence_number, 59 QuicTime::Delta delta_largest_observed); 60 61 bool IsEmpty() { return sequence_numbers_.empty(); } 62 63 // If a packet is retransmitted by the connection it will be sent with a 64 // different sequence number. Updates our internal set of sequence_numbers to 65 // track the latest number. 66 void UpdateSequenceNumber(QuicPacketSequenceNumber old_sequence_number, 67 QuicPacketSequenceNumber new_sequence_number); 68 69 private: 70 struct PacketInfo { 71 PacketInfo(); 72 explicit PacketInfo(int payload_size); 73 74 int packet_payload_size; 75 }; 76 77 // The delegate's OnAckNotification() method will be called once we have been 78 // notified of ACKs for all the sequence numbers we are tracking. 79 // This is not owned by OnAckNotifier and must outlive it. 80 scoped_refptr<DelegateInterface> delegate_; 81 82 // Sequence numbers this notifier is waiting to hear about. The 83 // delegate will not be called until this is empty. 84 base::hash_map<QuicPacketSequenceNumber, PacketInfo> sequence_numbers_; 85 86 // Transmission and retransmission stats. 87 // Number of packets in the original transmission. 88 int original_packet_count_; 89 // Number of packets in the original transmission. 90 int original_byte_count_; 91 // Number of packets that had to be retransmitted. 92 int retransmitted_packet_count_; 93 // Number of bytes that had to be retransmitted. 94 int retransmitted_byte_count_; 95 96 DISALLOW_COPY_AND_ASSIGN(QuicAckNotifier); 97 }; 98 99 }; // namespace net 100 101 #endif // NET_QUIC_QUIC_ACK_NOTIFIER_H_ 102
