utils/Burg/queue.c

   1 char rcsid_queue[] = "$Id$";
   2
   3 #include "b.h"
   4 #include <stdio.h>
   5
   6 Queue globalQ;
   7
   8 Queue
   9 newQ()
  10 {
  11   Queue q;
  12
  13   q = (Queue) zalloc(sizeof(struct queue));
  14   assert(q);
  15   q->head = 0;
  16   q->tail = 0;
  17
  18   return q;
  19 }
  20
  21 void
  22 addQ(q, ts) Queue q; Item_Set ts;
  23 {
  24   List qe;
  25
  26   assert(q);
  27   assert(ts);
  28
  29   qe = newList(ts, 0);
  30   if (q->head) {
  31     assert(q->tail);
  32     q->tail->next = qe;
  33     q->tail = qe;
  34   } else {
  35     q->head = q->tail = qe;
  36   }
  37 }
  38
  39 Item_Set
  40 popQ(q) Queue q;
  41 {
  42   List qe;
  43   Item_Set ts;
  44
  45   assert(q);
  46
  47   if (q->head) {
  48     qe = q->head;
  49     q->head = q->head->next;
  50     ts = (Item_Set) qe->x;
  51     zfree(qe);
  52     return ts;
  53   } else {
  54     return 0;
  55   }
  56 }
  57
  58 void
  59 dumpQ(q) Queue q;
  60 {
  61   printf("Begin Queue\n");
  62   foreachList((ListFn)dumpItem_Set, q->head);
  63   printf("End Queue\n");
  64 }