classifier-virtual.cc

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/* -*-  Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
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 *    must display the following acknowledgement:
 *      This product includes software developed by the MASH Research
 *      Group at the University of California Berkeley.
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#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /nfs/jade/vint/CVSROOT/ns-2/classifier/classifier-virtual.cc,v 1.12 2001/12/20 00:15:33 haldar Exp $";
#endif

extern "C" {
#include <tcl.h>
}
#include "config.h"
#include "packet.h"
#include "ip.h"
#include "classifier.h"
#include "route.h"
#include "object.h"
#include "address.h"

class VirtualClassifier : public Classifier {
public:
        VirtualClassifier() : routelogic_(0) {
                Tcl_InitHashTable(&ht_, TCL_ONE_WORD_KEYS);
        }
        ~VirtualClassifier() {
                Tcl_DeleteHashTable(&ht_);
        }
        virtual void do_install(char *dst, NsObject *target) { }
protected:
        NsObject* next_;
        Tcl_HashTable ht_;
        RouteLogic *routelogic_;
        NsObject* target_;
        bool enableHrouting_;
        char nodeaddr_[SMALL_LEN];

        int classify(Packet *const p) {
                hdr_ip* iph = hdr_ip::access(p);
                return mshift(iph->daddr());
        }
        
        void recv(Packet* p, Handler* h) {
                if (!routelogic_) {
                        Tcl &tcl = Tcl::instance();
                        tcl.evalc("[Simulator instance] get-routelogic");
                        routelogic_= (RouteLogic*) TclObject::lookup(tcl.result());
                        //tcl.evalf("%s info class", tcl.result());
                }
                /* first we find the next hop by asking routelogic
                 * then we use a hash next_hop -> target_object
                 * thus, the size of the table is at most N-1
                 */
                Tcl &tcl = Tcl::instance();
                hdr_ip* iph = hdr_ip::access(p);
                char* adst= Address::instance().print_nodeaddr(iph->daddr());
                //adst[strlen(adst)-1]= 0;
                target_= 0;

                int next_hopIP;
                routelogic_->lookup_flat(nodeaddr_, adst, next_hopIP);
                delete [] adst;

                int newEntry;
                Tcl_HashEntry *ep= Tcl_CreateHashEntry(&ht_, (const char*)next_hopIP, 
                                                       &newEntry); 
                if (newEntry) {
                        tcl.evalf("%s find %d", name(), next_hopIP);
                        Tcl_SetHashValue(ep, target_= (NsObject*)tcl.lookup(tcl.result()));
                } else {
                        target_= (NsObject*)Tcl_GetHashValue(ep);
                }
                
                if (!target_) {
                        /*
                         * XXX this should be "dropped" somehow.  Right now,
                         * these events aren't traced.
                         */
                        Packet::free(p);
                        return;
                }
                target_->recv(p,h);
        }
        int command(int argc, const char*const* argv) {
                if (argc == 3) {
                        if (strcmp(argv[1], "nodeaddr") == 0) {
                                strcpy(nodeaddr_, argv[2]);
                                return(TCL_OK);
                        }
                }
                return (NsObject::command(argc, argv));
        }
};

static class VirtualClassifierClass : public TclClass {
public:
        VirtualClassifierClass() : TclClass("Classifier/Virtual") {}
        TclObject* create(int, const char*const*) {
                return (new VirtualClassifier());
        }
} class_virtual_classifier;

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