git.ozlabs.org Git - ccan/blob - ccan/timer/_info

   1 #include "config.h"
   2 #include <stdio.h>
   3 #include <string.h>
   4
   5 /**
   6  * timer - efficient implementation of rarely-expiring timers.
   7  *
   8  * This is a lazy implementation of timers: you can add and delete timers
   9  * very quickly, and they are only sorted as their expiry approaches.
  10  *
  11  * This is a common case for timeouts, which must often be set, but
  12  * rarely expire.
  13  *
  14  * Example:
  15  *      // Silly example which outputs strings until timers expire.
  16  *      #include <ccan/timer/timer.h>
  17  *      #include <ccan/time/time.h>
  18  *      #include <stdlib.h>
  19  *      #include <stdio.h>
  20  *
  21  *      struct timed_string {
  22  *              struct list_node node;
  23  *              struct timer timer;
  24  *              const char *string;
  25  *      };
  26  *
  27  *      int main(int argc, char *argv[])
  28  *      {
  29  *              struct timers timers;
  30  *              struct list_head strings;
  31  *              struct list_head expired;
  32  *              struct timed_string *s;
  33  *
  34  *              timers_init(&timers, time_now());
  35  *              list_head_init(&strings);
  36  *
  37  *              while (argv[1]) {
  38  *                      s = malloc(sizeof(*s));
  39  *                      s->string = argv[1];
  40  *                      timer_add(&timers, &s->timer,
  41  *                                timeabs_add(time_now(),
  42  *                                            time_from_msec(atol(argv[2]))));
  43  *                      list_add_tail(&strings, &s->node);
  44  *                      argv += 2;
  45  *              }
  46  *
  47  *              while (!list_empty(&strings)) {
  48  *                      struct timeabs now = time_now();
  49  *                      list_for_each(&strings, s, node)
  50  *                              printf("%s", s->string);
  51  *                      timers_expire(&timers, now, &expired);
  52  *                      while ((s = list_pop(&expired, struct timed_string,
  53  *                                           timer.list)) != NULL) {
  54  *                              list_del_from(&strings, &s->node);
  55  *                              free(s);
  56  *                      }
  57  *              }
  58  *
  59  *              exit(0);
  60  *      }
  61  *
  62  * License: LGPL (v2.1 or any later version)
  63  * Author: Rusty Russell <rusty@rustcorp.com.au>
  64  */
  65 int main(int argc, char *argv[])
  66 {
  67         /* Expect exactly one argument */
  68         if (argc != 2)
  69                 return 1;
  70
  71         if (strcmp(argv[1], "depends") == 0) {
  72                 printf("ccan/array_size\n");
  73                 printf("ccan/ilog\n");
  74                 printf("ccan/likely\n");
  75                 printf("ccan/list\n");
  76                 printf("ccan/time\n");
  77                 return 0;
  78         }
  79
  80         return 1;
  81 }