utils/Burg/queue.c


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char rcsid_queue[] = "$Id$";

#include "b.h"
#include <stdio.h>

Queue globalQ;

Queue
newQ()
{
  Queue q;

  q = (Queue) zalloc(sizeof(struct queue));
  assert(q);
  q->head = 0;
  q->tail = 0;

  return q;
}

void
addQ(q, ts) Queue q; Item_Set ts;
{
  List qe;

  assert(q);
  assert(ts);

  qe = newList(ts, 0);
  if (q->head) {
    assert(q->tail);
    q->tail->next = qe;
    q->tail = qe;
  } else {
    q->head = q->tail = qe;
  }
}

Item_Set
popQ(q) Queue q;
{
  List qe;
  Item_Set ts;

  assert(q);

  if (q->head) {
    qe = q->head;
    q->head = q->head->next;
    ts = (Item_Set) qe->x;
    zfree(qe);
    return ts;
  } else {
    return 0;
  }
}

void
dumpQ(q) Queue q;
{
  printf("Begin Queue\n");
  foreachList((ListFn)dumpItem_Set, q->head);
  printf("End Queue\n");
}