/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2005, 2009 INRIA
* Copyright (c) 2009 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: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
* Author: Mirko Banchi <mk.banchi@gmail.com>
*/
#ifndef WIFI_MAC_QUEUE_H
#define WIFI_MAC_QUEUE_H
#include <list>
#include <utility>
#include "ns3/packet.h"
#include "ns3/nstime.h"
#include "ns3/object.h"
#include "wifi-mac-header.h"
namespace ns3 {
class WifiMacParameters;
/**
* \brief a 802.11e-specific queue.
*
* This queue implements what is needed for the 802.11e standard
* Specifically, it refers to 802.11e/D9, section 9.9.1.6, paragraph 6.
*
* When a packet is received by the MAC, to be sent to the PHY,
* it is queued in the internal queue after being tagged by the
* current time.
*
* When a packet is dequeued, the queue checks its timestamp
* to verify whether or not it should be dropped. If
* dot11EDCATableMSDULifetime has elapsed, it is dropped.
* Otherwise, it is returned to the caller.
*/
class WifiMacQueue : public Object
{
public:
static TypeId GetTypeId (void);
WifiMacQueue ();
~WifiMacQueue ();
void SetMaxSize (uint32_t maxSize);
void SetMaxDelay (Time delay);
uint32_t GetMaxSize (void) const;
Time GetMaxDelay (void) const;
void Enqueue (Ptr<const Packet> packet, const WifiMacHeader &hdr);
Ptr<const Packet> Dequeue (WifiMacHeader *hdr);
Ptr<const Packet> Peek (WifiMacHeader *hdr);
/**
* Searchs and returns, if is present in this queue, first packet having
* address indicated by <i>type</i> equals to <i>addr</i>, and tid
* equals to <i>tid</i>. This method removes the packet from this queue.
* Is typically used by ns3::EdcaTxopN in order to perform correct MSDU
* aggregation (A-MSDU).
*/
Ptr<const Packet> DequeueByTidAndAddress (WifiMacHeader *hdr,
uint8_t tid,
WifiMacHeader::AddressType type,
Mac48Address addr);
/**
* Searchs and returns, if is present in this queue, first packet having
* address indicated by <i>type</i> equals to <i>addr</i>, and tid
* equals to <i>tid</i>. This method doesn't remove the packet from this queue.
* Is typically used by ns3::EdcaTxopN in order to perform correct MSDU
* aggregation (A-MSDU).
*/
Ptr<const Packet> PeekByTidAndAddress (WifiMacHeader *hdr,
uint8_t tid,
WifiMacHeader::AddressType type,
Mac48Address addr);
/**
* If exists, removes <i>packet</i> from queue and returns true. Otherwise it
* takes no effects and return false. Deletion of the packet is
* performed in linear time (O(n)).
*/
bool Remove (Ptr<const Packet> packet);
void Flush (void);
bool IsEmpty (void);
uint32_t GetSize (void);
private:
struct Item;
typedef std::list<struct Item> PacketQueue;
typedef std::list<struct Item>::reverse_iterator PacketQueueRI;
typedef std::list<struct Item>::iterator PacketQueueI;
void Cleanup (void);
Mac48Address GetAddressForPacket (enum WifiMacHeader::AddressType type, PacketQueueI);
struct Item {
Item (Ptr<const Packet> packet,
const WifiMacHeader &hdr,
Time tstamp);
Ptr<const Packet> packet;
WifiMacHeader hdr;
Time tstamp;
};
PacketQueue m_queue;
WifiMacParameters *m_parameters;
uint32_t m_size;
uint32_t m_maxSize;
Time m_maxDelay;
};
} // namespace ns3
#endif /* WIFI_MAC_QUEUE_H */