<filename>ns-allinone-2.35/ns-2.35/adc/simple-intserv-sched.cc<gh_stars>1-10
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/*
 * Copyright (c) 1994 Regents of the University of California.
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 *	This product includes software developed by the Computer Systems
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#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /cvsroot/nsnam/ns-2/adc/simple-intserv-sched.cc,v 1.7 2005/08/26 05:05:28 tomh Exp $ (LBL)";
#endif


//Simple scheduler with 2 service priority levels and protects signalling
//ctrl  packets


#include "config.h"
#include "queue.h"

#define CLASSES 2

class SimpleIntServ : public Queue {
public:
	SimpleIntServ() {
		int i;
		char buf[10];
		for (i=0;i<CLASSES;i++) {
			q_[i] = new PacketQueue;
			qlimit_[i] = 0;
			sprintf(buf,"qlimit%d_",i);
			bind(buf,&qlimit_[i]);
		}
	}
	protected :
	void enque(Packet *);
	Packet *deque();
	PacketQueue *q_[CLASSES];
	int qlimit_[CLASSES];
};


static class SimpleIntServClass : public TclClass {
public:
	SimpleIntServClass() : TclClass("Queue/SimpleIntServ") {}
	TclObject* create(int, const char*const*) {
		return (new SimpleIntServ);
	}
} class_simple_intserv;

void SimpleIntServ::enque(Packet* p)
{
	
	hdr_ip* iph=hdr_ip::access(p);
	int cl=(iph->flowid()) ? 1:0;
	
	if (q_[cl]->length() >= (qlimit_[cl]-1)) {
		hdr_cmn* ch=hdr_cmn::access(p);
		packet_t ptype = ch->ptype();
		if ( (ptype != PT_REQUEST) && (ptype != PT_REJECT) && (ptype != PT_ACCEPT) && (ptype != PT_CONFIRM) && (ptype != PT_TEARDOWN) ) {
			drop(p);
		}
		else {
			q_[cl]->enque(p);
		}
	}
	else {
		q_[cl]->enque(p);
	}
}


Packet *SimpleIntServ::deque()
{
	int i;
	for (i=CLASSES-1;i>=0;i--)
		if (q_[i]->length())
			return q_[i]->deque();
	return 0;
}

