LayerIpMcast.cpp

#include "Headers.h"
#include "LayerIpMcast.h"

CLayerIpMcast::CLayerIpMcast(
    CSimHandler*    sim,
    __uint32        numGroups
    ) : CLayer(sim)
{
    this->numGroups = numGroups;

    // Groups
    this->groups = new CLayerIpMcastGroup[this->numGroups];

    // Memberships
    this->memberships = new CLayerIpMcastMembership[this->numGroups];

    // Delegates
    this->delegateRecv = new Delegate2<CLayerIpMcast, void, __uint32, CPacketIp*>(this, &CLayerIpMcast::Recv);
    this->delegateSend = new Delegate1<CLayerIpMcast, void, CPacketIp*>(this, &CLayerIpMcast::Send);
    this->delegateJoin =  new Delegate3<CLayerIpMcast, void, __uint32, CAddress, CLayerIpMcastGroup*>(this, &CLayerIpMcast::Join);
    this->delegateLeave = new Delegate3<CLayerIpMcast, void, __uint32, CAddress, CLayerIpMcastGroup*>(this, &CLayerIpMcast::Leave);
    this->delegateLocalJoin = new Delegate2<CLayerIpMcast, void, __uint32, CAddress>(this, &CLayerIpMcast::LocalJoin);
    this->delegateLocalLeave = new Delegate2<CLayerIpMcast, void, __uint32, CAddress>(this, &CLayerIpMcast::LocalLeave);

    // Events
    this->eventRecv = new Event2<void, __uint32, CPacketIp*>();
    this->eventSend = new Event2<void, __uint32, CPacketIp*>();
}

CLayerIpMcast::~CLayerIpMcast()
{
    delete[] this->groups;
    delete[] this->memberships;

    // Delegates
    delete this->delegateRecv;
    delete this->delegateSend;
    delete this->delegateJoin;
    delete this->delegateLeave;
    delete this->delegateLocalJoin;
    delete this->delegateLocalLeave;

    // Event
    delete this->eventRecv;
    delete this->eventSend;
}

void CLayerIpMcast::Recv(__uint32 entry, CPacketIp* packet)
{
    // Process only multicast packets addressed to a multicast group
    if(!packet->Dst().IsMulticastGroup()) return;

    // Calculate the group
    __uint32 group = packet->Dst().MulticastGroup();
    assert(group < this->numGroups);

    /*
     * Local forwarding
     */
    // If there is a local membership for this group send the packet payload to the upper layers
    if(this->memberships[group].State() == CLayerIpMcastMembership::MEMBER)
    {
        (*this->eventRecv)(entry, packet);
    }

    /*
     * Multicast routing
     */
    // Execute multicast forwarding only if TTL is greater than zero
    if(packet->Ttl() == 0) return;

    // Forward a copy of the packet to all output interfaces for this group except the inbound interface
    for(CLayerIpMcastGroup::Iterator iter = this->groups[group].Out()->begin(); iter != this->groups[group].Out()->end(); iter++)
    {
        if(*iter != entry)
        {
            (*this->eventSend)(*iter, type_cast<CPacketIp*>(packet->Copy()));
        }
    }
}

void CLayerIpMcast::Send(CPacketIp* packet)
{
    // Process only packets addressed to a multicast group
    if(!packet->Dst().IsMulticastGroup()) return;

    // Get the group
    __uint32 group = packet->Dst().MulticastGroup();
    assert(group < this->numGroups);

    // Forward the packet only if there is a membership for this group
    if(this->memberships[group].State() != CLayerIpMcastMembership::MEMBER) return;

    // Send the packet to the lower layer on the membership interface
    (*this->eventSend)(this->memberships[group].Entry(), packet);
}

void CLayerIpMcast::Join(__uint32 entry, CAddress address, CLayerIpMcastGroup* groupSender)
{
    __uint32 group = address.MulticastGroup();
    assert(group < this->numGroups);

    // Add interface to multicast group
    this->groups[group].Out()->insert(entry);
}

void CLayerIpMcast::Leave(__uint32 entry, CAddress address, CLayerIpMcastGroup* groupSender)
{
    __uint32 group = address.MulticastGroup();
    assert(group < this->numGroups);

    // Remove interface from multicast group
    this->groups[group].Out()->erase(entry);
}

void CLayerIpMcast::LocalJoin(__uint32 entry, CAddress address)
{
    __uint32 group = address.MulticastGroup();
    assert(group < this->numGroups);

    // Add membership for this group and interface
    this->memberships[group].Join(entry);
}

void CLayerIpMcast::LocalLeave(__uint32 entry, CAddress address)
{
    __uint32 group = address.MulticastGroup();
    assert(group < this->numGroups);

    // Remove membership for this group and interface
    this->memberships[group].Leave();
}