mac-rx-middle.h

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/*
 * Copyright (c) 2005 INRIA
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
 */
 
#ifndef MAC_RX_MIDDLE_H
#define MAC_RX_MIDDLE_H
 
#include "ns3/callback.h"
#include "ns3/simple-ref-count.h"
 
#include <map>
 
namespace ns3
{
 
class WifiMacHeader;
class OriginatorRxStatus;
class Packet;
class Mac48Address;
class WifiMpdu;
 
/**
 * \ingroup wifi
 *
 * This class handles duplicate detection and recomposition of fragments.
 */
class MacRxMiddle : public SimpleRefCount<MacRxMiddle>
{
  public:
    /**
     * typedef for callback
     */
    using ForwardUpCallback = Callback<void, Ptr<const WifiMpdu>, uint8_t /* link ID */>;
 
    MacRxMiddle();
    ~MacRxMiddle();
 
    /**
     * Set a callback to forward the packet up.
     *
     * \param callback the callback to set
     */
    void SetForwardCallback(ForwardUpCallback callback);
 
    /**
     * Receive an MPDU on the given link.
     *
     * \param mpdu the MPDU
     * \param linkId the ID of the given link
     */
    void Receive(Ptr<const WifiMpdu> mpdu, uint8_t linkId);
 
  private:
    /// allow MacRxMiddleTest associated class access
    friend class MacRxMiddleTest;
    /**
     * Look up for OriginatorRxStatus associated with the sender address
     * (by looking at ADDR2 field in the header).
     * The method creates a new OriginatorRxStatus if one is not already presented.
     *
     * \param hdr the MAC header
     *
     * \return OriginatorRxStatus
     */
    OriginatorRxStatus& Lookup(const WifiMacHeader& hdr);
    /**
     * Check if we have already received the packet from the sender before
     * (by looking at the sequence control field).
     *
     * \param hdr the MAC header
     * \param originator the packet originator status
     *
     * \return true if we already received the packet previously,
     *         false otherwise
     */
    bool IsDuplicate(const WifiMacHeader& hdr, const OriginatorRxStatus& originator) const;
    /**
     * Check if the received packet is a fragment and handle it appropriately.
     * If the packet is not a fragment, the method returns the packet.
     * If the packet is a fragment (not the last fragment), the method initiates
     * de-fragmentation process and return 0.
     * If the packet is the last fragment, the method tries to re-construct the full packet
     * and return the packet if success.
     *
     * \param packet the packet
     * \param hdr the MAC header
     * \param originator the packet originator status
     *
     * \return a packet if the packet is successfully reassembled (or not a fragment),
     *         0 if we failed to reassemble the packet (e.g. missing fragments/out-of-order).
     */
    Ptr<const Packet> HandleFragments(Ptr<const Packet> packet,
                                      const WifiMacHeader& hdr,
                                      OriginatorRxStatus& originator);
 
    /**
     * typedef for a map between address and OriginatorRxStatus
     */
    using Originators = std::map<Mac48Address, OriginatorRxStatus, std::less<>>;
 
    /**
     * typedef for a map between address, OriginatorRxStatus, and Traffic ID
     */
    using QosOriginators =
        std::map<std::pair<Mac48Address, uint8_t>, OriginatorRxStatus, std::less<>>;
 
    /**
     * typedef for an iterator for Originators
     */
    using OriginatorsI = std::map<Mac48Address, OriginatorRxStatus, std::less<>>::iterator;
 
    /**
     * typedef for an iterator for QosOriginators
     */
    using QosOriginatorsI =
        std::map<std::pair<Mac48Address, uint8_t>, OriginatorRxStatus, std::less<>>::iterator;
 
    Originators m_originatorStatus;       ///< originator status
    QosOriginators m_qosOriginatorStatus; ///< QOS originator status
    ForwardUpCallback m_callback;         ///< forward up callback
};
 
} // namespace ns3
 
#endif /* MAC_RX_MIDDLE_H */