nptl/tst-flock1.c

   1 /* Copyright (C) 2002 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <pthread.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <sys/file.h>
  25
  26
  27 static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
  28
  29 static int fd;
  30
  31
  32 static void *
  33 tf (void *arg)
  34 {
  35   if (flock (fd, LOCK_SH | LOCK_NB) != 0)
  36     {
  37       puts ("second flock failed");
  38       exit (1);
  39     }
  40
  41   pthread_mutex_unlock (&lock);
  42
  43   return NULL;
  44 }
  45
  46
  47 static int
  48 do_test (void)
  49 {
  50   char tmp[] = "/tmp/tst-flock1-XXXXXX";
  51
  52   fd = mkstemp (tmp);
  53   if (fd == -1)
  54     {
  55       puts ("mkstemp failed");
  56       exit (1);
  57     }
  58
  59   unlink (tmp);
  60
  61   write (fd, "foobar xyzzy", 12);
  62
  63   if (flock (fd, LOCK_EX | LOCK_NB) != 0)
  64     {
  65       puts ("first flock failed");
  66       exit (1);
  67     }
  68
  69   pthread_mutex_lock (&lock);
  70
  71   pthread_t th;
  72   if (pthread_create (&th, NULL, tf, NULL) != 0)
  73     {
  74       puts ("pthread_create failed");
  75       exit (1);
  76     }
  77
  78   pthread_mutex_lock (&lock);
  79
  80   void *result;
  81   if (pthread_join (th, &result) != 0)
  82     {
  83       puts ("pthread_join failed");
  84       exit (1);
  85     }
  86
  87   close (fd);
  88
  89   return result != NULL;
  90 }
  91
  92 #define TEST_FUNCTION do_test ()
  93 #include "../test-skeleton.c"