channel-access-manager.h

Go to the documentation of this file.

/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2005,2006 INRIA
 *
 * 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: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
 */

#ifndef CHANNEL_ACCESS_MANAGER_H
#define CHANNEL_ACCESS_MANAGER_H

#include <vector>
#include "ns3/event-id.h"
#include "ns3/nstime.h"

namespace ns3 {

class WifiPhy;
class PhyListener;
class Txop;
class MacLow;

class ChannelAccessManager : public Object
{
public:
  ChannelAccessManager ();
  virtual ~ChannelAccessManager ();

  void SetupPhyListener (Ptr<WifiPhy> phy);
  void RemovePhyListener (Ptr<WifiPhy> phy);
  void SetupLow (Ptr<MacLow> low);

  void SetSlot (Time slotTime);
  void SetSifs (Time sifs);
  void SetEifsNoDifs (Time eifsNoDifs);

  Time GetEifsNoDifs () const;

  void Add (Ptr<Txop> dcf);

  void RequestAccess (Ptr<Txop> state, bool isCfPeriod = false);

  void NotifyRxStartNow (Time duration);
  void NotifyRxEndOkNow (void);
  void NotifyRxEndErrorNow (void);
  void NotifyTxStartNow (Time duration);
  void NotifyMaybeCcaBusyStartNow (Time duration);
  void NotifySwitchingStartNow (Time duration);
  void NotifySleepNow (void);
  void NotifyOffNow (void);
  void NotifyWakeupNow (void);
  void NotifyOnNow (void);
  void NotifyNavResetNow (Time duration);
  void NotifyNavStartNow (Time duration);
  void NotifyAckTimeoutStartNow (Time duration);
  void NotifyAckTimeoutResetNow ();
  void NotifyCtsTimeoutStartNow (Time duration);
  void NotifyCtsTimeoutResetNow ();

  bool IsBusy (void) const;


protected:
  // Inherited from ns3::Object
  void DoDispose (void);


private:
  void UpdateBackoff (void);
  Time MostRecent (Time a, Time b) const;
  Time MostRecent (Time a, Time b, Time c, Time d, Time e, Time f) const;
  Time MostRecent (Time a, Time b, Time c, Time d, Time e, Time f, Time g) const;
  Time GetAccessGrantStart (bool ignoreNav = false) const;
  Time GetBackoffStartFor (Ptr<Txop> state);
  Time GetBackoffEndFor (Ptr<Txop> state);

  void DoRestartAccessTimeoutIfNeeded (void);

  void AccessTimeout (void);
  void DoGrantAccess (void);
  bool IsWithinAifs (Ptr<Txop> state) const;
  void GrantPcfAccess (Ptr<Txop> state);

  typedef std::vector<Ptr<Txop> > States;

  States m_states;              
  Time m_lastAckTimeoutEnd;     
  Time m_lastCtsTimeoutEnd;     
  Time m_lastNavStart;          
  Time m_lastNavDuration;       
  Time m_lastRxStart;           
  Time m_lastRxDuration;        
  bool m_lastRxReceivedOk;      
  Time m_lastRxEnd;             
  Time m_lastTxStart;           
  Time m_lastTxDuration;        
  Time m_lastBusyStart;         
  Time m_lastBusyDuration;      
  Time m_lastSwitchingStart;    
  Time m_lastSwitchingDuration; 
  bool m_rxing;                 
  bool m_sleeping;              
  bool m_off;                   
  Time m_eifsNoDifs;            
  EventId m_accessTimeout;      
  Time m_slot;                  
  Time m_sifs;                  
  PhyListener* m_phyListener;   
};

} //namespace ns3

#endif /* CHANNEL_ACCESS_MANAGER_H */