d-tail.cc

在网络仿真模拟工具下实现支持QoS的MAC层EDCF协议

// derived from drop-tail.cc

#include <cmu-trace.h>
#include "d-tail.h"

#include "iostream.h"

static class DTailClass : public TclClass {
 public:
	DTailClass() : TclClass("Queue/DTail") {}
	TclObject* create(int, const char*const*) {
		return (new DTail);
	}
} class_d_tail;

void DTail::reset()
{
	Queue::reset();
}

int 
DTail::command(int argc, const char*const* argv) {

	if (argc==2) {
		if (strcmp(argv[1], "printstats") == 0) {
			print_summarystats();
			return (TCL_OK);
		}
	}
	if (argc == 3) {
		if (!strcmp(argv[1], "packetqueue-attach")) {
			delete q_;
			if (!(q_ = (PacketQueue*) TclObject::lookup(argv[2])))
				return (TCL_ERROR);
			else {
				pq_ = q_;
				return (TCL_OK);
			}
		}
	}
	return Queue::command(argc, argv);
}

/*
 * drop-tail
 */
void DTail::target_handle(NsObject* targ){
    target_ = targ;
}

void DTail::recv(Packet* p, Handler *h)
{
    Queue::recv(p,h);
}

void DTail::enque(Packet* p)
{
    	if (summarystats) {
                Queue::updateStats(qib_?q_->byteLength():q_->length());
	}
	int qlimBytes = qlim_ * mean_pktsize_;
	if ((!qib_ && (q_->length() + 1) >= qlim_) ||
  	(qib_ && (q_->byteLength() + hdr_cmn::access(p)->size()) >= qlimBytes)){
	    
            // if the queue would overflow if we added this packet...
		if (drop_front_) { /* remove from head of queue */
		        q_->enque(p);
			Packet *pp = q_->deque();
			drop(pp);
		} else {
		    drop(p);
		}
	} else {
	    q_->enque(p);
	}
}

Packet* DTail::deque()
{
        if (summarystats && &Scheduler::instance() != NULL) {
                Queue::updateStats(qib_?q_->byteLength():q_->length());
        }
	return q_->deque();
}

void DTail::print_summarystats()
{
	//double now = Scheduler::instance().clock();
        printf("True average queue: %5.3f", true_ave_);
        if (qib_)
                printf(" (in bytes)");
        printf(" time: %5.3f\n", total_time_);
}

void DTail::setPF(int pf){
    PF = pf;
}
void DTail::setCW_MIN(int cw_min){
    CW_MIN = cw_min;
}
void DTail::setCW_MAX(int cw_max){
    CW_MAX = cw_max;
}
void DTail::setAIFS(int aifs){
    AIFS = aifs;
}

void DTail::setTXOPLimit(double limit){
    LIMIT = limit;
}

int DTail::getPF(){
    return PF;
}
int DTail::getCW_MIN(){
    return CW_MIN;
}

int DTail::getCW_MAX(){
    return CW_MAX;
}
int DTail::getAIFS(){
    return AIFS;
}

double DTail::getTXOPLimit(){
    return LIMIT;
}

int DTail::getLen(){
    return Queue::length();
}

int DTail::getByteLen(){
    return Queue::byteLength();
}

void DTail::recvHighPri(Packet *p) {
    target_->recv(p, &qh_);
}

void DTail::setdrop(NsObject* getdrop_) {
    drop_ = getdrop_;
}

//added by smallko
double DTail::getavgLen() {
    double qweight1=0.1;
    avgquelen=double((1-qweight1)*(Queue::length()) + qweight1*avgquelen);
    return avgquelen;
}