inet::ieee80211::Rx Class Reference

The default implementation of IRx. More...

#include <Rx.h>

Inheritance diagram for inet::ieee80211::Rx:

Public Member Functions
	Rx ()
	~Rx ()
virtual bool	isReceptionInProgress () const override
virtual bool	isMediumFree () const override
virtual void	receptionStateChanged (IRadio::ReceptionState newReceptionState) override
virtual void	transmissionStateChanged (IRadio::TransmissionState transmissionState) override
virtual void	receivedSignalPartChanged (IRadioSignal::SignalPart part) override
virtual bool	lowerFrameReceived (Ieee80211Frame *frame) override
virtual void	frameTransmitted (simtime_t durationField) override
virtual void	registerContention (IContention *contention) override
Public Member Functions inherited from inet::ieee80211::IRx
virtual	~IRx ()

Protected Member Functions
virtual int	numInitStages () const override
virtual void	initialize (int stage) override
virtual void	handleMessage (cMessage *msg) override
virtual void	setOrExtendNav (simtime_t navInterval)
virtual bool	isFcsOk (Ieee80211Frame *frame) const
virtual void	recomputeMediumFree ()
virtual void	refreshDisplay () const override

Protected Attributes
std::vector< IContention * >	contentions
IStatistics *	statistics = nullptr
MACAddress	address
cMessage *	endNavTimer = nullptr
IRadio::ReceptionState	receptionState = IRadio::RECEPTION_STATE_UNDEFINED
IRadio::TransmissionState	transmissionState = IRadio::TRANSMISSION_STATE_UNDEFINED
IRadioSignal::SignalPart	receivedPart = IRadioSignal::SIGNAL_PART_NONE
bool	mediumFree = true

Detailed Description

The default implementation of IRx.

Constructor & Destructor Documentation

inet::ieee80211::Rx::Rx

(

)

{
}

inet::ieee80211::Rx::~Rx

(

)

{
    cancelAndDelete(endNavTimer);
}

Member Function Documentation

void inet::ieee80211::Rx::frameTransmitted ( simtime_t  durationField )

overridevirtual

Implements inet::ieee80211::IRx.

{
    Enter_Method_Silent();
    // the txIndex that transmitted the frame should already own the TXOP, so
    // it has no need to (and should not) check the NAV.
    setOrExtendNav(durationField);
}

void inet::ieee80211::Rx::handleMessage ( cMessage *  msg )

overrideprotectedvirtual

{
    if (msg == endNavTimer) {
        EV_INFO << "The radio channel has become free according to the NAV" << std::endl;
        recomputeMediumFree();
    }
    else
        throw cRuntimeError("Unexpected self message");
}

void inet::ieee80211::Rx::initialize ( int  stage )

overrideprotectedvirtual

{
    if (stage == INITSTAGE_LOCAL) {
        endNavTimer = new cMessage("NAV");
        WATCH(address);
        WATCH(receptionState);
        WATCH(transmissionState);
        WATCH(mediumFree);
    }
    else if (stage == INITSTAGE_LINK_LAYER) {
        // statistics = check_and_cast<IStatistics *>(getModuleByPath(par("statisticsModule")));
        address = check_and_cast<Ieee80211Mac*>(getContainingNicModule(this)->getSubmodule("mac"))->getAddress();
        recomputeMediumFree();
    }
}

bool inet::ieee80211::Rx::isFcsOk ( Ieee80211Frame *  frame ) const

protectedvirtual

Referenced by lowerFrameReceived().

{
    return !frame->hasBitError();
}

virtual bool inet::ieee80211::Rx::isMediumFree ( ) const

inlineoverridevirtual

Implements inet::ieee80211::IRx.

{ return mediumFree; }

bool inet::ieee80211::Rx::isReceptionInProgress ( ) const

overridevirtual

Implements inet::ieee80211::IRx.

{
    return receptionState == IRadio::RECEPTION_STATE_RECEIVING &&
           (receivedPart == IRadioSignal::SIGNAL_PART_WHOLE || receivedPart == IRadioSignal::SIGNAL_PART_DATA);
}

bool inet::ieee80211::Rx::lowerFrameReceived ( Ieee80211Frame *  frame )

overridevirtual

Implements inet::ieee80211::IRx.

{
    Enter_Method("lowerFrameReceived(\"%s\")", frame->getName());
    take(frame);

    bool isFrameOk = isFcsOk(frame);
    if (isFrameOk) {
        EV_INFO << "Received frame from PHY: " << frame << endl;
        if (frame->getReceiverAddress() != address)
            setOrExtendNav(frame->getDuration());
//        statistics->frameReceived(frame);
        return true;
    }
    else {
        EV_INFO << "Received an erroneous frame from PHY, dropping it." << std::endl;
        delete frame;
        for (auto contention : contentions)
            contention->corruptedFrameReceived();
//        statistics->erroneousFrameReceived();
        return false;
    }
}

virtual int inet::ieee80211::Rx::numInitStages ( ) const

inlineoverrideprotectedvirtual

{ return NUM_INIT_STAGES; }

void inet::ieee80211::Rx::receivedSignalPartChanged ( IRadioSignal::SignalPart  part )

overridevirtual

Implements inet::ieee80211::IRx.

{
    Enter_Method_Silent();
    receivedPart = part;
    recomputeMediumFree();
}

void inet::ieee80211::Rx::receptionStateChanged ( IRadio::ReceptionState  newReceptionState )

overridevirtual

Implements inet::ieee80211::IRx.

{
    Enter_Method_Silent();
    receptionState = state;
    recomputeMediumFree();
}

void inet::ieee80211::Rx::recomputeMediumFree ( )

protectedvirtual

Referenced by handleMessage(), initialize(), receivedSignalPartChanged(), receptionStateChanged(), setOrExtendNav(), and transmissionStateChanged().

{
    bool oldMediumFree = mediumFree;
    // note: the duration of mode switching (rx-to-tx or tx-to-rx) should also count as busy
    mediumFree = receptionState == IRadio::RECEPTION_STATE_IDLE && transmissionState == IRadio::TRANSMISSION_STATE_UNDEFINED && !endNavTimer->isScheduled();
    if (mediumFree != oldMediumFree) {
        for (auto contention : contentions)
            contention->mediumStateChanged(mediumFree);
    }
}

void inet::ieee80211::Rx::refreshDisplay ( ) const

overrideprotectedvirtual

{
    if (mediumFree)
        getDisplayString().setTagArg("t", 0, "FREE");
    else {
        std::stringstream os;
        os << "BUSY (";
        bool addSpace = false;
        if (transmissionState != IRadio::TRANSMISSION_STATE_UNDEFINED) {
            switch (transmissionState) {
                case IRadio::IRadio::TRANSMISSION_STATE_UNDEFINED: break; // cannot happen
                case IRadio::IRadio::TRANSMISSION_STATE_IDLE: os << "Tx-Idle"; break;
                case IRadio::IRadio::TRANSMISSION_STATE_TRANSMITTING: os << "Tx"; break;
            }
            addSpace = true;
        }
        else {
            switch (receptionState) {
                case IRadio::RECEPTION_STATE_UNDEFINED: os << "Switching"; break;
                case IRadio::RECEPTION_STATE_IDLE: os << "Rx-Idle"; break; // cannot happen
                case IRadio::RECEPTION_STATE_BUSY: os << "Noise"; break;
                case IRadio::RECEPTION_STATE_RECEIVING: os << "Recv"; break;
            }
            addSpace = true;
        }
        if (endNavTimer->isScheduled()) {
            os << (addSpace ? " " : "") << "NAV";
        }
        os << ")";
        getDisplayString().setTagArg("t", 0, os.str().c_str());
    }
}

void inet::ieee80211::Rx::registerContention ( IContention *  contention )

overridevirtual

Implements inet::ieee80211::IRx.

{
    contention->mediumStateChanged(mediumFree);
    contentions.push_back(contention);
}

void inet::ieee80211::Rx::setOrExtendNav ( simtime_t  navInterval )

protectedvirtual

Referenced by frameTransmitted(), and lowerFrameReceived().

{
    ASSERT(navInterval >= 0);
    if (navInterval > 0) {
        simtime_t endNav = simTime() + navInterval;
        if (endNavTimer->isScheduled()) {
            simtime_t oldEndNav = endNavTimer->getArrivalTime();
            if (endNav < oldEndNav)
                return;    // never decrease NAV
            cancelEvent(endNavTimer);
        }
        EV_INFO << "Setting NAV to " << navInterval << std::endl;
        scheduleAt(endNav, endNavTimer);
        recomputeMediumFree();
    }
}

void inet::ieee80211::Rx::transmissionStateChanged ( IRadio::TransmissionState  transmissionState )

overridevirtual

Implements inet::ieee80211::IRx.

{
    Enter_Method_Silent();
    transmissionState = state;
    recomputeMediumFree();
}

Member Data Documentation

MACAddress inet::ieee80211::Rx::address

protected

Referenced by initialize(), and lowerFrameReceived().

std::vector<IContention *> inet::ieee80211::Rx::contentions

protected

Referenced by lowerFrameReceived(), recomputeMediumFree(), and registerContention().

cMessage* inet::ieee80211::Rx::endNavTimer = nullptr

protected

Referenced by handleMessage(), initialize(), recomputeMediumFree(), refreshDisplay(), setOrExtendNav(), and ~Rx().

bool inet::ieee80211::Rx::mediumFree = true

protected

Referenced by initialize(), recomputeMediumFree(), refreshDisplay(), and registerContention().

IRadioSignal::SignalPart inet::ieee80211::Rx::receivedPart = IRadioSignal::SIGNAL_PART_NONE

protected

Referenced by isReceptionInProgress(), and receivedSignalPartChanged().

IRadio::ReceptionState inet::ieee80211::Rx::receptionState = IRadio::RECEPTION_STATE_UNDEFINED

protected

Referenced by initialize(), isReceptionInProgress(), receptionStateChanged(), recomputeMediumFree(), and refreshDisplay().

IStatistics* inet::ieee80211::Rx::statistics = nullptr

protected

IRadio::TransmissionState inet::ieee80211::Rx::transmissionState = IRadio::TRANSMISSION_STATE_UNDEFINED

protected

Referenced by initialize(), recomputeMediumFree(), refreshDisplay(), and transmissionStateChanged().

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The documentation for this class was generated from the following files:

• Rx.h
• Rx.cc