1  /* Test for sem_post race: bug 14532.
       2     Copyright (C) 2012-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <pthread.h>
      20  #include <semaphore.h>
      21  #include <stdio.h>
      22  
      23  #define NTHREADS 10
      24  #define NITER 100000
      25  
      26  sem_t sem;
      27  int c;
      28  volatile int thread_fail;
      29  
      30  static void *
      31  tf (void *arg)
      32  {
      33    for (int i = 0; i < NITER; i++)
      34      {
      35        if (sem_wait (&sem) != 0)
      36  	{
      37  	  perror ("sem_wait");
      38  	  thread_fail = 1;
      39  	}
      40        ++c;
      41        if (sem_post (&sem) != 0)
      42  	{
      43  	  perror ("sem_post");
      44  	  thread_fail = 1;
      45  	}
      46      }
      47    return NULL;
      48  }
      49  
      50  static int
      51  do_test (void)
      52  {
      53    if (sem_init (&sem, 0, 0) != 0)
      54      {
      55        perror ("sem_init");
      56        return 1;
      57      }
      58  
      59    pthread_t th[NTHREADS];
      60    for (int i = 0; i < NTHREADS; i++)
      61      {
      62        if (pthread_create (&th[i], NULL, tf, NULL) != 0)
      63  	{
      64  	  puts ("pthread_create failed");
      65  	  return 1;
      66  	}
      67      }
      68  
      69    if (sem_post (&sem) != 0)
      70      {
      71        perror ("sem_post");
      72        return 1;
      73      }
      74  
      75    for (int i = 0; i < NTHREADS; i++)
      76      if (pthread_join (th[i], NULL) != 0)
      77        {
      78  	puts ("pthread_join failed");
      79  	return 1;
      80        }
      81  
      82    if (c != NTHREADS * NITER)
      83      {
      84        printf ("c = %d, should be %d\n", c, NTHREADS * NITER);
      85        return 1;
      86      }
      87    return thread_fail;
      88  }
      89  
      90  #define TEST_FUNCTION do_test ()
      91  #include "../test-skeleton.c"