sysdeps/pthread/tst-cond1.c

   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_cond_t cond = PTHREAD_COND_INITIALIZER;
  25 static pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;
  26
  27
  28 static void *
  29 tf (void *p)
  30 {
  31   int err;
  32
  33   err = pthread_mutex_lock (&mut);
  34   if (err != 0)
  35     error (EXIT_FAILURE, err, "child: cannot get mutex");
  36
  37   puts ("child: got mutex; signalling");
  38
  39   pthread_cond_signal (&cond);
  40
  41   puts ("child: unlock");
  42
  43   err = pthread_mutex_unlock (&mut);
  44   if (err != 0)
  45     error (EXIT_FAILURE, err, "child: cannot unlock");
  46
  47   puts ("child: done");
  48
  49   return NULL;
  50 }
  51
  52
  53 static int
  54 do_test (void)
  55 {
  56   pthread_t th;
  57   int err;
  58
  59   printf ("&cond = %p\n&mut = %p\n", &cond, &mut);
  60
  61   puts ("parent: get mutex");
  62
  63   err = pthread_mutex_lock (&mut);
  64   if (err != 0)
  65     error (EXIT_FAILURE, err, "parent: cannot get mutex");
  66
  67   puts ("parent: create child");
  68
  69   err = pthread_create (&th, NULL, tf, NULL);
  70   if (err != 0)
  71     error (EXIT_FAILURE, err, "parent: cannot create thread");
  72
  73   puts ("parent: wait for condition");
  74
  75   /* This test will fail on spurious wake-ups, which are allowed; however,
  76      the current implementation shouldn't produce spurious wake-ups in the
  77      scenario we are testing here.  */
  78   err = pthread_cond_wait (&cond, &mut);
  79   if (err != 0)
  80     error (EXIT_FAILURE, err, "parent: cannot wait fir signal");
  81
  82   puts ("parent: got signal");
  83
  84   err = pthread_join (th, NULL);
  85   if (err != 0)
  86     error (EXIT_FAILURE, err, "parent: failed to join");
  87
  88   puts ("done");
  89
  90   return 0;
  91 }
  92
  93
  94 #define TEST_FUNCTION do_test ()
  95 #include "../test-skeleton.c"