regress/lib/libpthread/mutex1/mutex1.c

   1 /*      $NetBSD$        */
   2
   3 #include <assert.h>
   4 #include <err.h>
   5 #include <pthread.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <unistd.h>
   9
  10 void *threadfunc(void *arg);
  11
  12 pthread_mutex_t mutex;
  13
  14 int
  15 main(int argc, char *argv[])
  16 {
  17         int x,ret;
  18         pthread_t new;
  19         void *joinval;
  20
  21         printf("1: Mutex-test 1\n");
  22
  23         pthread_mutex_init(&mutex, NULL);
  24         x = 1;
  25         pthread_mutex_lock(&mutex);
  26         ret = pthread_create(&new, NULL, threadfunc, &x);
  27         if (ret != 0)
  28                 err(1, "pthread_create");
  29         printf("1: Before changing the value.\n");
  30         sleep(2);
  31         x = 20;
  32         printf("1: Before releasing the mutex.\n");
  33         sleep(2);
  34         pthread_mutex_unlock(&mutex);
  35         printf("1: After releasing the mutex.\n");
  36         ret = pthread_join(new, &joinval);
  37         if (ret != 0)
  38                 err(1, "pthread_join");
  39
  40         pthread_mutex_lock(&mutex);
  41         printf("1: Thread joined. X was %d. Return value (int) was %d\n",
  42             x, *(int *)joinval);
  43         assert(x == 21);
  44         assert(*(int *)joinval == 21);
  45         pthread_mutex_unlock(&mutex);
  46         return 0;
  47 }
  48
  49 void *
  50 threadfunc(void *arg)
  51 {
  52         int *param;
  53
  54         printf("2: Second thread.\n");
  55
  56         param = arg;
  57         printf("2: Locking mutex\n");
  58         pthread_mutex_lock(&mutex);
  59         printf("2: Got mutex. *param = %d\n", *param);
  60         assert(*param == 20);
  61         (*param)++;
  62
  63         pthread_mutex_unlock(&mutex);
  64
  65         return param;
  66 }