tcp-tx-buffer.h

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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2010-2015 Adrian Sai-wah Tam
 * Copyright (c) 2016 Natale Patriciello <natale.patriciello@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Original author: Adrian Sai-wah Tam <adrian.sw.tam@gmail.com>
 */
 
#ifndef TCP_TX_BUFFER_H
#define TCP_TX_BUFFER_H
 
#include "ns3/object.h"
#include "ns3/traced-value.h"
#include "ns3/sequence-number.h"
#include "ns3/tcp-option-sack.h"
#include "ns3/tcp-tx-item.h"
 
namespace ns3 {
class Packet;
 
class TcpTxBuffer : public Object
{
public:
  static TypeId GetTypeId (void);
  TcpTxBuffer (uint32_t n = 0);
  virtual ~TcpTxBuffer (void);
 
  // Accessors
 
  SequenceNumber32 HeadSequence (void) const;
 
  SequenceNumber32 TailSequence (void) const;
 
  uint32_t Size (void) const;
 
  uint32_t MaxBufferSize (void) const;
 
  void SetMaxBufferSize (uint32_t n);
 
  bool IsSackEnabled (void) const;
 
  void SetSackEnabled (bool enabled);
 
  uint32_t Available (void) const;
 
  void SetDupAckThresh (uint32_t dupAckThresh);
 
  void SetSegmentSize (uint32_t segmentSize);
 
  uint32_t GetRetransmitsCount (void) const;
 
  uint32_t GetLost (void) const;
 
  uint32_t GetSacked (void) const;
 
  bool Add (Ptr<Packet> p);
 
  uint32_t SizeFromSequence (const SequenceNumber32& seq) const;
 
  TcpTxItem* CopyFromSequence (uint32_t numBytes, const SequenceNumber32& seq);
 
  void SetHeadSequence (const SequenceNumber32& seq);
 
  bool IsRetransmittedDataAcked (const SequenceNumber32& ack) const;
 
  void DiscardUpTo (const SequenceNumber32& seq,
                    const Callback<void, TcpTxItem *> &beforeDelCb = m_nullCb);
 
  uint32_t Update (const TcpOptionSack::SackList &list,
                   const Callback<void, TcpTxItem *> &sackedCb = m_nullCb);
 
  bool IsLost (const SequenceNumber32 &seq) const;
 
  bool NextSeg (SequenceNumber32 *seq, SequenceNumber32 *seqHigh, bool isRecovery) const;
 
  uint32_t BytesInFlight () const;
 
  void SetSentListLost (bool resetSack = false);
 
  bool IsHeadRetransmitted () const;
 
  void DeleteRetransmittedFlagFromHead ();
 
  void ResetSentList ();
 
  void ResetLastSegmentSent ();
 
  void MarkHeadAsLost ();
 
  void AddRenoSack ();
 
  void ResetRenoSack ();
 
  void SetRWndCallback (Callback<uint32_t> rWndCallback);
 
private:
  friend std::ostream & operator<< (std::ostream & os, TcpTxBuffer const & tcpTxBuf);
 
  typedef std::list<TcpTxItem*> PacketList; 
 
  void UpdateLostCount ();
 
  void RemoveFromCounts (TcpTxItem *item, uint32_t size);
 
  bool IsLostRFC (const SequenceNumber32 &seq, const PacketList::const_iterator &segment) const;
 
  uint32_t BytesInFlightRFC () const;
 
  TcpTxItem* GetNewSegment (uint32_t numBytes);
 
  TcpTxItem* GetTransmittedSegment (uint32_t numBytes, const SequenceNumber32 &seq);
 
  TcpTxItem* GetPacketFromList (PacketList &list, const SequenceNumber32 &startingSeq,
                                uint32_t numBytes, const SequenceNumber32 &requestedSeq,
                                bool *listEdited = nullptr) const;
 
  void MergeItems (TcpTxItem *t1, TcpTxItem *t2) const;
 
  void SplitItems (TcpTxItem *t1, TcpTxItem *t2, uint32_t size) const;
 
  void ConsistencyCheck () const;
 
  std::pair <TcpTxBuffer::PacketList::const_iterator, SequenceNumber32>
  FindHighestSacked () const;
 
  PacketList m_appList;  
  PacketList m_sentList; 
  uint32_t m_maxBuffer;  
  uint32_t m_size;       
  uint32_t m_sentSize;   
  Callback<uint32_t> m_rWndCallback; 
 
  TracedValue<SequenceNumber32> m_firstByteSeq; 
  std::pair <PacketList::const_iterator, SequenceNumber32> m_highestSack; 
 
  uint32_t m_lostOut   {0}; 
  uint32_t m_sackedOut {0}; 
  uint32_t m_retrans   {0}; 
 
  uint32_t m_dupAckThresh {0}; 
  uint32_t m_segmentSize {0}; 
  bool     m_renoSack {false}; 
  bool     m_sackEnabled {true}; 
 
  static Callback<void, TcpTxItem *> m_nullCb; 
};
 
std::ostream & operator<< (std::ostream & os, TcpTxBuffer const & tcpTxBuf);
 
std::ostream & operator<< (std::ostream & os, TcpTxItem const & item);
 
} // namespace ns3
 
#endif /* TCP_TX_BUFFER_H */