drop-tail.h

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 *  This product includes software developed by the Computer Systems
 *  Engineering Group at Lawrence Berkeley Laboratory.
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 * @(#) $Header: /nfs/jade/vint/CVSROOT/ns-2/queue/drop-tail.h,v 1.19 2004/10/28 23:35:37 haldar Exp $ (LBL)
 */

#ifndef ns_drop_tail_h
#define ns_drop_tail_h

#include <string.h>
#include "queue.h"
#include "config.h"

/*
 * A bounded, drop-tail queue
 */
class DropTail : public Queue {
  public:
    DropTail() { 
        q_ = new PacketQueue; 
        pq_ = q_;
        bind_bool("drop_front_", &drop_front_);
        bind_bool("summarystats_", &summarystats);
        bind_bool("queue_in_bytes_", &qib_);  // boolean: q in bytes?
        bind("mean_pktsize_", &mean_pktsize_);
        //      _RENAMED("drop-front_", "drop_front_");
    }
    ~DropTail() {
        delete q_;
    }
  protected:
    void reset();
    int command(int argc, const char*const* argv); 
    void enque(Packet*);
    Packet* deque();
    void shrink_queue();    // To shrink queue and drop excessive packets.

    PacketQueue *q_;    /* underlying FIFO queue */
    int drop_front_;    /* drop-from-front (rather than from tail) */
    int summarystats;
    void print_summarystats();
    int qib_;           /* bool: queue measured in bytes? */
    int mean_pktsize_;  /* configured mean packet size in bytes */
};

#endif

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