sa.cc.cc

在网络的边缘路由器中并不能完全接受所到的包

/* -*-	Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (c) Xerox Corporation 1997. All rights reserved.
 *
 * License is granted to copy, to use, and to make and to use derivative
 * works for research and evaluation purposes, provided that Xerox is
 * acknowledged in all documentation pertaining to any such copy or
 * derivative work. Xerox grants no other licenses expressed or
 * implied. The Xerox trade name should not be used in any advertising
 * without its written permission. 
 *
 * XEROX CORPORATION MAKES NO REPRESENTATIONS CONCERNING EITHER THE
 * MERCHANTABILITY OF THIS SOFTWARE OR THE SUITABILITY OF THIS SOFTWARE
 * FOR ANY PARTICULAR PURPOSE.  The software is provided "as is" without
 * express or implied warranty of any kind.
 *
 * These notices must be retained in any copies of any part of this
 * software. 
 */

//packets after it succeeds in a3-way handshake from the receiver
// should be connected with Agent/SignalAck class

#include "udp.h"
#include "sa.h"
#include "ip.h"
#include "packet.h"
#include "random.h"

#define SAMPLERATE 8000

SA_Agent::SA_Agent() : Agent(PT_UDP), trafgen_(0), rtd_(0), callback_(0), 
    sa_timer_(this), nextPkttime_(-1), running_(0), seqno_(-1)
{
	bind ("off_resv_",&off_resv_);
	bind("off_rtp_", &off_rtp_);
	bind_bw("rate_",&rate_);
	bind("bucket_",&bucket_);
	bind("packetSize_", &size_);
        bind("off_ip_", &off_ip_);

        //begin archanakrishna
          bind("ingressnodeofpacket_", (int*)&ingressnodeofpacket_);
          bind("egressnodeofpacket_", (int*)&egressnodeofpacket_);
          bind("classofpacket_", &classofpacket_);
        //end archanakrishna

}

SA_Agent::~SA_Agent()
{
        if (callback_) 
                delete[] callback_;

}


static class SA_AgentClass : public TclClass {
public:
	SA_AgentClass() : TclClass("Agent/SA") {}
	TclObject* create(int, const char*const*) {
		return (new SA_Agent());
	}
} class_signalsource_agent;

int SA_Agent::command(int argc, const char*const* argv)
{
	Tcl& tcl = Tcl::instance();
	if (argc==3) {
		if (strcmp(argv[1], "target") == 0) {
			target_ = (NsObject*)TclObject::lookup(argv[2]);
			if (target_ == 0) {
				tcl.resultf("no such object %s", argv[2]);
				return (TCL_ERROR);
			}
			ctrl_target_=target_;
			return (TCL_OK);
		} 
		else if (strcmp(argv[1],"ctrl-target")== 0) {
			ctrl_target_=(NsObject*)TclObject::lookup(argv[2]);
			if (ctrl_target_ == 0) {
				tcl.resultf("no such object %s", argv[2]);
				return (TCL_ERROR);
			}
			return (TCL_OK);
		}
	        if (strcmp(argv[1], "stoponidle") == 0) {
		        stoponidle(argv[2]);
			return(TCL_OK);
		}
                if (strcmp(argv[1], "attach-traffic") == 0) {
                        trafgen_ =(TrafficGenerator*)TclObject::lookup(argv[2]);
                        if (trafgen_ == 0) {
                                tcl.resultf("no such node %s", argv[2]);
                                return(TCL_ERROR);
                        }
                        return(TCL_OK);
                }

	}
        if (argc == 2) {
                if (strcmp(argv[1], "start") == 0) {
                        start();
                        return(TCL_OK);
                } else if (strcmp(argv[1], "stop") == 0) {
                        stop();
                        return(TCL_OK);
                }
        }
	return (Agent::command(argc,argv));
}


void SA_Agent::start()
{
	//send the request packet
	if (trafgen_) {
		trafgen_->init();
		//running_=1;
		sendreq();
              
	}
}

void SA_Agent::stop()
{
	sendteardown();
	if (running_ != 0) {
		sa_timer_.cancel();
		running_ =0;
	}
}


void SA_Agent::sendreq()
{
	Packet *p = allocpkt();
	hdr_cmn* ch= (hdr_cmn*)p->access(off_cmn_);
	ch->ptype()=PT_REQUEST;
	ch->size()=20;
	//also put in the r,b parameters for the flow in the packet
	hdr_resv* rv=(hdr_resv*)p->access(off_resv_);
	rv->decision() =1;
	rv->rate()=rate_;
	rv->bucket()=bucket_;

	ctrl_target_->recv(p);

        // begin archanakrishna
        //        double arrivaltime = ch->arrivaltimestamp();
        //        double servicetime = ch->servicetimestamp();
        //        printf("The arrival time is %f \n",arrivaltime);
        //        printf("The service time is %f \n",servicetime);
        // end archanakrishna

}

void SA_Agent::sendteardown()
{
	Packet *p = allocpkt();
	hdr_cmn* ch= (hdr_cmn*)p->access(off_cmn_);
	ch->ptype()=PT_TEARDOWN;
	ch->size()=20;
	//also put in the r,b parameters for the flow in the packet
	hdr_resv* rv=(hdr_resv*)p->access(off_resv_);
	rv->decision() =1;
	rv->rate()=rate_;
	rv->bucket()=bucket_;
	ctrl_target_->recv(p);
}


void SA_Agent::recv(Packet *p, Handler *) 
{
	hdr_cmn *ch= (hdr_cmn *)p->access(off_cmn_);
	hdr_resv *rv=(hdr_resv *)p->access(off_resv_);
	hdr_ip * iph = (hdr_ip*)p->access(off_ip_);
	if ( ch->ptype() == PT_ACCEPT || ch->ptype() == PT_REJECT ) {
		ch->ptype() = PT_CONFIRM;
		// turn the packet around by swapping src and dst
		nsaddr_t tmp;
		tmp = iph->src();
		iph->src()=iph->dst();
		iph->dst()=tmp;
		ctrl_target_->recv(p);
		
	}
	
	// put an additional check here to see if admission was granted
	if (rv->decision()) {
		//printf("Flow %d accepted @ %f\n",iph->flowid(),Scheduler::instance().clock());
		fflush(stdout);
		double t = trafgen_->next_interval(size_);
		running_=1;
		sa_timer_.resched(t);
	}
	else {
		//printf("Flow %d rejected @ %f\n",iph->flowid(),Scheduler::instance().clock());
		fflush(stdout);
		//Currently the flow is stopped if rejected
		running_=0;
	}
	//make an upcall to sched a stoptime for this flow from now
	Tcl::instance().evalf("%s sched-stop %d",name(),rv->decision());
}

void SA_Agent::stoponidle(const char *s)
{
        callback_ = new char[strlen(s)+1];
        strcpy(callback_, s);

        if (trafgen_->on()) {
                // Tcl::instance().evalf("puts \"%s waiting for burst at %f\"", name(), Scheduler::instance().clock());
                rtd_ = 1;
        }
        else {
                stop();
                Tcl::instance().evalf("%s %s", name(), callback_);
        }

}

void SA_Timer::expire(Event* /*e*/) {
        a_->timeout(0);
}

void SA_Agent::timeout(int)
{
        if (running_) {
                /* send a packet */
                sendpkt();
                /* figure out when to send the next one */
                nextPkttime_ = trafgen_->next_interval(size_);
                /* schedule it */
                sa_timer_.resched(nextPkttime_);

                /* hack: if we are waiting for a current burst to end
                 * before stopping . . .
                 */
                if (rtd_) {
                        if (trafgen_->on() == 0) {
                                stop();
                                //Tcl::instance().evalf("puts \"%s burst over at %f\"",
                                // name(), Scheduler::instance().clock());
                                Tcl::instance().evalf("%s sched-stop %d", name(), 0);
                        }
                }
        }
}

void SA_Agent::sendpkt()
{
        Packet* p = allocpkt();
        hdr_rtp* rh = (hdr_rtp*)p->access(off_rtp_);
        hdr_ip *iph=(hdr_ip*)p->access(off_ip_);
        rh->seqno() = ++seqno_;
        rh->flags()=0;

        double local_time=Scheduler::instance().clock();
        /*put in "rtp timestamps" and begining of talkspurt labels */
        hdr_cmn* ch = (hdr_cmn*)p->access(off_cmn_);
        ch->timestamp()=(u_int32_t)(SAMPLERATE*local_time);
        ch->size()=size_;

        //begin archanakrishna
          ch->pktingressnode() = ingressnodeofpacket_;
          ch->pktegressnode() = egressnodeofpacket_;
          ch->classofpacket() = classofpacket_;
        //end archanakrishna 

        if ((nextPkttime_ != trafgen_->interval()) || (nextPkttime_ == -1))
                rh->flags() |= RTP_M;

        // begin archanakrishna

       // printf("\n In SA_Agent::sendpkt() function the seqno,flowid and unique id of the packet are \n seqno = %d , flowid = %d, unique id = %d \n",rh->seqno(),iph->flowid(),ch->uid());

        // end archanakrishna


        target_->recv(p);
}

void SA_Agent::sendmsg(int nbytes, const char* /*flags*/)
{
        Packet *p;
        int n;

        if (size_)
                n = nbytes / size_;
        else
                printf("Error: SA_Agent size = 0\n");

        if (nbytes == -1) {
                start();
                return;
        }
        while (n-- > 0) {
       		p = allocpkt();
                hdr_rtp* rh = (hdr_rtp*)p->access(off_rtp_);
                rh->seqno() = seqno_;
                target_->recv(p);
        }
        n = nbytes % size_;
        if (n > 0) {
        	p = allocpkt();
        	hdr_rtp* rh = (hdr_rtp*)p->access(off_rtp_);
        	rh->seqno() = seqno_;
        	target_->recv(p);
        }
        idle();
}