nptl/tst-sem14.c

   1 /* Test for sem_post race: bug 14532.
   2    Copyright (C) 2012-2019 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"