block-ack-manager.h

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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2009, 2010 MIRKO BANCHI
 *
 * 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
 *
 * Author: Mirko Banchi <mk.banchi@gmail.com>
 */

#ifndef BLOCK_ACK_MANAGER_H
#define BLOCK_ACK_MANAGER_H

#include <map>
#include "ns3/nstime.h"
#include "wifi-mac-header.h"
#include "originator-block-ack-agreement.h"
#include "block-ack-type.h"

namespace ns3 {

class WifiRemoteStationManager;
class MgtAddBaResponseHeader;
class MgtAddBaRequestHeader;
class CtrlBAckResponseHeader;
class MacTxMiddle;
class WifiMacQueue;
class WifiMode;
class Packet;

struct Bar
{
  Bar ();
  Bar (Ptr<const Packet> packet,
       Mac48Address recipient,
       uint8_t tid,
       bool immediate);
  Ptr<const Packet> bar; 
  Mac48Address recipient; 
  uint8_t tid; 
  bool immediate; 
};


class BlockAckManager : public Object
{
private:
  BlockAckManager (const BlockAckManager&);
  BlockAckManager& operator= (const BlockAckManager& block);


public:
  static TypeId GetTypeId (void);

  BlockAckManager ();
  ~BlockAckManager ();

  void SetWifiRemoteStationManager (const Ptr<WifiRemoteStationManager> manager);
  bool ExistsAgreement (Mac48Address recipient, uint8_t tid) const;
  bool ExistsAgreementInState (Mac48Address recipient, uint8_t tid,
                               OriginatorBlockAckAgreement::State state) const;
  void CreateAgreement (const MgtAddBaRequestHeader *reqHdr, Mac48Address recipient);
  void DestroyAgreement (Mac48Address recipient, uint8_t tid);
  void UpdateAgreement (const MgtAddBaResponseHeader *respHdr, Mac48Address recipient);
  void StorePacket (Ptr<const Packet> packet, const WifiMacHeader &hdr, Time tStamp);
  Ptr<const Packet> GetNextPacket (WifiMacHeader &hdr, bool removePacket);
  bool HasBar (Bar &bar);
  bool HasPackets (void) const;
  void NotifyGotBlockAck (const CtrlBAckResponseHeader *blockAck, Mac48Address recipient, double rxSnr, WifiMode txMode, double dataSnr);
  uint32_t GetNBufferedPackets (Mac48Address recipient, uint8_t tid) const;
  uint32_t GetNRetryNeededPackets (Mac48Address recipient, uint8_t tid) const;
  void NotifyAgreementEstablished (Mac48Address recipient, uint8_t tid, uint16_t startingSeq);
  void NotifyAgreementUnsuccessful (Mac48Address recipient, uint8_t tid);
  void NotifyMpduTransmission (Mac48Address recipient, uint8_t tid, uint16_t nextSeqNumber, WifiMacHeader::QosAckPolicy policy);
  void CompleteAmpduExchange (Mac48Address recipient, uint8_t tid);
  void SetBlockAckThreshold (uint8_t nPackets);

  void SetQueue (const Ptr<WifiMacQueue> queue);
  void SetTxMiddle (const Ptr<MacTxMiddle> txMiddle);

  void SetBlockAckType (BlockAckType bAckType);
  void SetMaxPacketDelay (Time maxDelay);

  void SetBlockAckInactivityCallback (Callback<void, Mac48Address, uint8_t, bool> callback);
  void SetBlockDestinationCallback (Callback<void, Mac48Address, uint8_t> callback);
  void SetUnblockDestinationCallback (Callback<void, Mac48Address, uint8_t> callback);

  bool SwitchToBlockAckIfNeeded (Mac48Address recipient, uint8_t tid, uint16_t startingSeq);
  uint16_t GetSeqNumOfNextRetryPacket (Mac48Address recipient, uint8_t tid) const;
  bool AlreadyExists (uint16_t currentSeq, Mac48Address recipient, uint8_t tid) const;
  bool RemovePacket (uint8_t tid, Mac48Address recipient, uint16_t seqnumber);
  Ptr<const Packet> PeekNextPacketByTidAndAddress (WifiMacHeader &hdr, uint8_t tid, Time *timestamp);
  bool NeedBarRetransmission (uint8_t tid, uint16_t seqNumber, Mac48Address recipient);

  typedef Callback <void, const WifiMacHeader&> TxOk;
  typedef Callback <void, const WifiMacHeader&> TxFailed;
  void SetTxOkCallback (TxOk callback);
  void SetTxFailedCallback (TxFailed callback);


private:
  Ptr<Packet> ScheduleBlockAckReqIfNeeded (Mac48Address recipient, uint8_t tid);

  void CleanupBuffers (void);
  void InactivityTimeout (Mac48Address recipient, uint8_t tid);

  struct Item;
  typedef std::list<Item> PacketQueue;
  typedef std::list<Item>::iterator PacketQueueI;
  typedef std::list<Item>::const_iterator PacketQueueCI;
  typedef std::map<std::pair<Mac48Address, uint8_t>,
                   std::pair<OriginatorBlockAckAgreement, PacketQueue> > Agreements;
  typedef std::map<std::pair<Mac48Address, uint8_t>,
                   std::pair<OriginatorBlockAckAgreement, PacketQueue> >::iterator AgreementsI;
  typedef std::map<std::pair<Mac48Address, uint8_t>,
                   std::pair<OriginatorBlockAckAgreement, PacketQueue> >::const_iterator AgreementsCI;

  struct Item
  {
    Item (Ptr<const Packet> packet,
          const WifiMacHeader &hdr,
          Time tStamp);
    Ptr<const Packet> packet; 
    WifiMacHeader hdr; 
    Time timestamp; 
  };
  void InsertInRetryQueue (PacketQueueI item);

  void RemoveFromRetryQueue (Mac48Address address, uint8_t tid, uint16_t seq);

  Agreements m_agreements;

  std::list<PacketQueueI> m_retryPackets;
  std::list<Bar> m_bars; 

  uint8_t m_blockAckThreshold; 
  BlockAckType m_blockAckType; 
  Time m_maxDelay; 
  Ptr<MacTxMiddle> m_txMiddle; 
  Mac48Address m_address; 
  Ptr<WifiMacQueue> m_queue; 
  Callback<void, Mac48Address, uint8_t, bool> m_blockAckInactivityTimeout; 
  Callback<void, Mac48Address, uint8_t> m_blockPackets; 
  Callback<void, Mac48Address, uint8_t> m_unblockPackets; 
  TxOk m_txOkCallback; 
  TxFailed m_txFailedCallback; 
  Ptr<WifiRemoteStationManager> m_stationManager; 
};

} //namespace ns3

#endif /* BLOCK_ACK_MANAGER_H */