Export QUIC response retransmit packet and byte counts via faster stats.

net/quic/quic_ack_notifier.h

 // 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();
-    virtual void OnAckNotification() = 0;
-
+    // 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);
-
-  // Register a set of sequence numbers that this AckNotifier should be
-  // interested in.
-  void AddSequenceNumbers(const SequenceNumberSet& sequence_numbers);
+  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_;
 
-  // Set of sequence numbers this notifier is waiting to hear about. The
-  // delegate will not be called until this is an empty set.
-  SequenceNumberSet sequence_numbers_;
+  // 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_