// Copyright 2013 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_ACK_NOTIFIER_H_
#define NET_QUIC_QUIC_ACK_NOTIFIER_H_
#include "base/memory/ref_counted.h"
#include "net/quic/quic_protocol.h"
namespace net {
// Used to register with a QuicConnection for notification once a set of packets
// have all been ACKed.
// The connection informs this class of newly ACKed sequence numbers, and once
// we have seen ACKs for all the sequence numbers we are interested in, we
// trigger a call to a provided Closure.
class NET_EXPORT_PRIVATE QuicAckNotifier {
public:
class NET_EXPORT_PRIVATE DelegateInterface
: public base::RefCounted<DelegateInterface> {
public:
DelegateInterface();
// Args:
// num_original_packets - Number of packets in the original transmission.
// num_original_bytes - Number of packets in the original transmission.
// num_retransmitted_packets - Number of packets that had to be
// retransmitted.
// num_retransmitted_bytes - Number of bytes that had to be retransmitted.
virtual void OnAckNotification(int num_original_packets,
int num_original_bytes,
int num_retransmitted_packets,
int num_retransmitted_bytes) = 0;
protected:
friend class base::RefCounted<DelegateInterface>;
// Delegates are ref counted.
virtual ~DelegateInterface();
};
// QuicAckNotifier is expected to keep its own reference to the delegate.
explicit QuicAckNotifier(DelegateInterface* delegate);
virtual ~QuicAckNotifier();
// Register a sequence number that this AckNotifier should be interested in.
void AddSequenceNumber(const QuicPacketSequenceNumber& sequence_number,
int packet_payload_size);
// Called by the QuicConnection on receipt of new ACK frame, with the sequence
// number referenced by the ACK frame.
// Deletes the matching sequence number from the stored set of sequence
// numbers. If this set is now empty, call the stored delegate's
// OnAckNotification method.
//
// Returns true if the provided sequence_number caused the delegate to be
// called, false otherwise.
bool OnAck(QuicPacketSequenceNumber sequence_number);
bool IsEmpty() { return sequence_numbers_.empty(); }
// If a packet is retransmitted by the connection it will be sent with a
// different sequence number. Updates our internal set of sequence_numbers to
// track the latest number.
void UpdateSequenceNumber(QuicPacketSequenceNumber old_sequence_number,
QuicPacketSequenceNumber new_sequence_number);
private:
struct PacketInfo {
PacketInfo();
explicit PacketInfo(int payload_size);
int packet_payload_size;
};
// The delegate's OnAckNotification() method will be called once we have been
// notified of ACKs for all the sequence numbers we are tracking.
// This is not owned by OnAckNotifier and must outlive it.
scoped_refptr<DelegateInterface> delegate_;
// Sequence numbers this notifier is waiting to hear about. The
// delegate will not be called until this is empty.
base::hash_map<QuicPacketSequenceNumber, PacketInfo> sequence_numbers_;
// Transmission and retransmission stats.
// Number of packets in the original transmission.
int original_packet_count_;
// Number of packets in the original transmission.
int original_byte_count_;
// Number of packets that had to be retransmitted.
int retransmitted_packet_count_;
// Number of bytes that had to be retransmitted.
int retransmitted_byte_count_;
};
}; // namespace net
#endif // NET_QUIC_QUIC_ACK_NOTIFIER_H_