Land Recent QUIC changes.

net/quic/quic_ack_notifier.h

+// Copyright (c) 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/callback.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:
+    DelegateInterface();
+    virtual ~DelegateInterface();
+    virtual void OnAckNotification() = 0;
+  };
+
+  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);
+
+  // Called by the QuicConnection on receipt of new ACK frames with a list of
+  // ACKed sequence numbers.
+  // Deletes any matching sequence numbers from the set of sequence numbers
+  // being tracked. If this set is now empty, call the stored delegate's
+  // OnAckNotification method.
+  //
+  // Returns true if the provided sequence_numbers caused the delegate to be
+  // called, false otherwise.
+  bool OnAck(SequenceNumberSet sequence_numbers);
+
+  // 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:
+  // 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.
+  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_;
+};
+
+};  // namespace net
+
+#endif  // NET_QUIC_QUIC_ACK_NOTIFIER_H_