1  /* Copyright (C) 2002-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <error.h>
      19  #include <pthread.h>
      20  #include <stdio.h>
      21  #include <stdlib.h>
      22  
      23  
      24  static pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;
      25  static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
      26  
      27  static pthread_barrier_t bar;
      28  
      29  
      30  static void *
      31  tf (void *a)
      32  {
      33    int i = (long int) a;
      34    int err;
      35  
      36    printf ("child %d: lock\n", i);
      37  
      38    err = pthread_mutex_lock (&mut);
      39    if (err != 0)
      40      error (EXIT_FAILURE, err, "locking in child failed");
      41  
      42    printf ("child %d: sync\n", i);
      43  
      44    int e = pthread_barrier_wait (&bar);
      45    if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
      46      {
      47        puts ("child: barrier_wait failed");
      48        exit (1);
      49      }
      50  
      51    printf ("child %d: wait\n", i);
      52  
      53    err = pthread_cond_wait (&cond, &mut);
      54    if (err != 0)
      55      error (EXIT_FAILURE, err, "child %d: failed to wait", i);
      56  
      57    printf ("child %d: woken up\n", i);
      58  
      59    err = pthread_mutex_unlock (&mut);
      60    if (err != 0)
      61      error (EXIT_FAILURE, err, "child %d: unlock[2] failed", i);
      62  
      63    printf ("child %d: done\n", i);
      64  
      65    return NULL;
      66  }
      67  
      68  
      69  #define N 10
      70  
      71  
      72  static int
      73  do_test (void)
      74  {
      75    pthread_t th[N];
      76    int i;
      77    int err;
      78  
      79    printf ("&cond = %p\n&mut = %p\n", &cond, &mut);
      80  
      81    if (pthread_barrier_init (&bar, NULL, 2) != 0)
      82      {
      83        puts ("barrier_init failed");
      84        exit (1);
      85      }
      86  
      87    pthread_attr_t at;
      88  
      89    if (pthread_attr_init (&at) != 0)
      90      {
      91        puts ("attr_init failed");
      92        return 1;
      93      }
      94  
      95    if (pthread_attr_setstacksize (&at, 1 * 1024 * 1024) != 0)
      96      {
      97        puts ("attr_setstacksize failed");
      98        return 1;
      99      }
     100  
     101    for (i = 0; i < N; ++i)
     102      {
     103        printf ("create thread %d\n", i);
     104  
     105        err = pthread_create (&th[i], &at, tf, (void *) (long int) i);
     106        if (err != 0)
     107  	error (EXIT_FAILURE, err, "cannot create thread %d", i);
     108  
     109        printf ("wait for child %d\n", i);
     110  
     111        /* Wait for the child to start up and get the mutex for the
     112  	 conditional variable.  */
     113        int e = pthread_barrier_wait (&bar);
     114        if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
     115  	{
     116  	  puts ("barrier_wait failed");
     117  	  exit (1);
     118  	}
     119      }
     120  
     121    if (pthread_attr_destroy (&at) != 0)
     122      {
     123        puts ("attr_destroy failed");
     124        return 1;
     125      }
     126  
     127    puts ("get lock ourselves");
     128  
     129    err = pthread_mutex_lock (&mut);
     130    if (err != 0)
     131      error (EXIT_FAILURE, err, "mut locking failed");
     132  
     133    puts ("broadcast");
     134  
     135    /* Wake up all threads.  */
     136    err = pthread_cond_broadcast (&cond);
     137    if (err != 0)
     138      error (EXIT_FAILURE, err, "parent: broadcast failed");
     139  
     140    err = pthread_mutex_unlock (&mut);
     141    if (err != 0)
     142      error (EXIT_FAILURE, err, "mut unlocking failed");
     143  
     144    /* Join all threads.  */
     145    for (i = 0; i < N; ++i)
     146      {
     147        printf ("join thread %d\n", i);
     148  
     149        err = pthread_join (th[i], NULL);
     150        if (err != 0)
     151  	error (EXIT_FAILURE, err, "join of child %d failed", i);
     152      }
     153  
     154    puts ("done");
     155  
     156    return 0;
     157  }
     158  
     159  
     160  #define TEST_FUNCTION do_test ()
     161  #include "../test-skeleton.c"