regress/lib/libpthread/cond4/cond4.c

   1 /*      $NetBSD: cond4.c,v 1.1 2003/01/30 18:53:48 thorpej Exp $        */
   2
   3 #include <assert.h>
   4 #include <err.h>
   5 #include <pthread.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8
   9 void *threadfunc(void *arg);
  10
  11 pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
  12 pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
  13 int count, total, toggle;
  14 #define COUNT 50000
  15
  16 int main(int argc, char *argv[])
  17 {
  18         int ret;
  19         pthread_t new;
  20         void *joinval;
  21         int sharedval;
  22
  23         printf("1: condition variable test 4\n");
  24
  25         ret = pthread_mutex_lock(&mutex);
  26         if (ret)
  27                 err(1, "pthread_mutex_lock(1)");
  28
  29         count = COUNT;
  30         toggle = 0;
  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         while (count>0) {
  38                 count--;
  39                 total++;
  40                 toggle = 1;
  41 #if 0
  42                 printf("1: Before signal %d.\n", count);
  43 #endif
  44                 pthread_cond_signal(&cond);
  45                 do {
  46                         pthread_cond_wait(&cond, &mutex);
  47                 } while (toggle != 0);
  48         }
  49         printf("1: After the loop.\n");
  50
  51         toggle = 1;
  52         pthread_mutex_unlock(&mutex);
  53         pthread_cond_signal(&cond);
  54
  55         printf("1: After releasing the mutex.\n");
  56         ret = pthread_join(new, &joinval);
  57         if (ret != 0)
  58                 err(1, "pthread_join");
  59
  60         printf("1: Thread joined. Final count = %d, total = %d\n",
  61             count, total);
  62         assert(count == 0);
  63         assert(total == COUNT);
  64
  65         return 0;
  66 }
  67
  68 void *threadfunc(void *arg)
  69 {
  70 #if 0
  71         int *share = (int *) arg;
  72 #endif
  73
  74         printf("2: Second thread.\n");
  75         pthread_mutex_lock(&mutex);
  76         printf("2: Before the loop.\n");
  77         while (count>0) {
  78                 count--;
  79                 total++;
  80                 toggle = 0;
  81 #if 0
  82                 printf("2: Before signal %d.\n", count);
  83 #endif
  84                 pthread_cond_signal(&cond);
  85                 do {
  86                         pthread_cond_wait(&cond, &mutex);
  87                 } while (toggle != 1);
  88         }
  89         printf("2: After the loop.\n");
  90         pthread_mutex_unlock(&mutex);
  91
  92         return NULL;
  93 }