regress/lib/libpthread/cond2/cond2.c

   1 /*      $NetBSD$        */
   2
   3 #include <err.h>
   4 #include <pthread.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <unistd.h>
   8
   9 void *threadfunc(void *arg);
  10
  11 pthread_mutex_t mutex;
  12 pthread_cond_t cond;
  13
  14 int
  15 main(int argc, char *argv[])
  16 {
  17         int x,ret;
  18         pthread_t new;
  19         void *joinval;
  20         int sharedval;
  21
  22         printf("1: condition variable test 2\n");
  23
  24         pthread_mutex_init(&mutex, NULL);
  25         pthread_cond_init(&cond, NULL);
  26
  27         x = 20;
  28         pthread_mutex_lock(&mutex);
  29
  30         sharedval = 1;
  31
  32         ret = pthread_create(&new, NULL, threadfunc, &sharedval);
  33         if (ret != 0)
  34                 err(1, "pthread_create");
  35
  36         printf("1: Before waiting.\n");
  37         do {
  38                 sleep(2);
  39                 pthread_cond_wait(&cond, &mutex);
  40                 printf("1: After waiting, in loop.\n");
  41         } while (sharedval != 0);
  42
  43         printf("1: After the loop.\n");
  44
  45         pthread_mutex_unlock(&mutex);
  46
  47         printf("1: After releasing the mutex.\n");
  48         ret = pthread_join(new, &joinval);
  49         if (ret != 0)
  50                 err(1, "pthread_join");
  51
  52         printf("1: Thread joined.\n");
  53
  54         return 0;
  55 }
  56
  57 void *
  58 threadfunc(void *arg)
  59 {
  60         int *share = (int *) arg;
  61
  62         printf("2: Second thread.\n");
  63
  64         printf("2: Locking mutex\n");
  65         pthread_mutex_lock(&mutex);
  66         printf("2: Got mutex.\n");
  67         printf("Shared value: %d. Changing to 0.\n", *share);
  68         *share = 0;
  69
  70         /* Signal first, then unlock, for a different test than #1. */
  71         pthread_cond_signal(&cond);
  72         pthread_mutex_unlock(&mutex);
  73
  74         return NULL;
  75 }