source: vendor/glibc-tests/glibc/nptl/tst-cond18.c

/* Copyright (C) 2004 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Jakub Jelinek <jakub@redhat.com>, 2004.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>

pthread_cond_t cv = PTHREAD_COND_INITIALIZER;
pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
bool exiting;
int fd, count, spins, nn;

void *
tf (void *id)
{
  pthread_mutex_lock (&lock);

  if ((long) id == 0)
    {
      while (!exiting)
        {
          if ((spins++ % 1000) == 0)
            write (fd, ".", 1);
          pthread_mutex_unlock (&lock);

          pthread_mutex_lock (&lock);
          int njobs = rand () % (count + 1);
          nn = njobs;
          if ((rand () % 30) == 0)
            pthread_cond_broadcast (&cv);
          else
            while (njobs--)
              pthread_cond_signal (&cv);
        }

      pthread_cond_broadcast (&cv);
    }
  else
    {
      while (!exiting)
        {
          while (!nn && !exiting)
            pthread_cond_wait (&cv, &lock);
          --nn;
          pthread_mutex_unlock (&lock);

          pthread_mutex_lock (&lock);
        }
    }

  pthread_mutex_unlock (&lock);
  return NULL;
}

int
do_test (void)
{
  fd = open ("/dev/null", O_WRONLY);
  if (fd < 0)
    {
      printf ("couldn't open /dev/null, %m\n");
      return 1;
    }

  count = sysconf (_SC_NPROCESSORS_ONLN);
  if (count <= 0)
    count = 1;
  count *= 8;

  pthread_t th[count + 1];
  int i, ret;

  for (i = 0; i <= count; ++i)
    if ((ret = pthread_create (&th[i], NULL, tf, (void *) (long) i)) != 0)
      {
        errno = ret;
        printf ("pthread_create %d failed: %m\n", i);
        return 1;
      }

  struct timespec ts = { .tv_sec = 20, .tv_nsec = 0 };
  while (nanosleep (&ts, &ts) != 0);

  pthread_mutex_lock (&lock);
  exiting = true;
  pthread_mutex_unlock (&lock);

  for (i = 0; i < count; ++i)
    pthread_join (th[i], NULL);

  close (fd);
  return 0;
}

#define TEST_FUNCTION do_test ()
#define TIMEOUT 40
#include "../test-skeleton.c"