nptl/tst-rwlock12.c

   1 /* Copyright (C) 2002, 2003 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 <errno.h>
  21 #include <pthread.h>
  22 #include <stdint.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #include <sys/mman.h>
  28 #include <sys/wait.h>
  29
  30
  31 static int
  32 do_test (void)
  33 {
  34 #if ! _POSIX_THREAD_PROCESS_SHARED
  35
  36   puts ("_POSIX_THREAD_PROCESS_SHARED not supported, test skipped");
  37   return 0;
  38
  39 #else
  40
  41   size_t ps = sysconf (_SC_PAGESIZE);
  42   char tmpfname[] = "/tmp/tst-rwlock12.XXXXXX";
  43   char data[ps];
  44   void *mem;
  45   int fd;
  46   pthread_mutex_t *m;
  47   pthread_mutexattr_t ma;
  48   pthread_rwlock_t *r;
  49   pthread_rwlockattr_t ra;
  50   pid_t pid;
  51   int status = 0;
  52
  53   fd = mkstemp (tmpfname);
  54   if (fd == -1)
  55     {
  56       printf ("cannot open temporary file: %m\n");
  57       return 1;
  58     }
  59
  60   /* Make sure it is always removed.  */
  61   unlink (tmpfname);
  62
  63   /* Create one page of data.  */
  64   memset (data, '\0', ps);
  65
  66   /* Write the data to the file.  */
  67   if (write (fd, data, ps) != (ssize_t) ps)
  68     {
  69       puts ("short write");
  70       return 1;
  71     }
  72
  73   mem = mmap (NULL, ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
  74   if (mem == MAP_FAILED)
  75     {
  76       printf ("mmap failed: %m\n");
  77       return 1;
  78     }
  79
  80   r = (pthread_rwlock_t *) (((uintptr_t) mem + __alignof (pthread_rwlock_t))
  81                             & ~(__alignof (pthread_rwlock_t) - 1));
  82   /* The following assumes alignment for a mutex is at least as high
  83      as that for a rwlock.  Which is true in our case.  */
  84   m = (pthread_mutex_t *) (r + 1);
  85
  86   if (pthread_rwlockattr_init (&ra) != 0)
  87     {
  88       puts ("rwlockattr_init failed");
  89       return 1;
  90     }
  91
  92   if (pthread_rwlockattr_setpshared (&ra, PTHREAD_PROCESS_SHARED) != 0)
  93     {
  94       puts ("rwlockattr_setpshared failed");
  95       return 1;
  96     }
  97
  98   if (pthread_rwlock_init (r, &ra) != 0)
  99     {
 100       puts ("rwlock_init failed");
 101       return 1;
 102     }
 103
 104   if (pthread_mutexattr_init (&ma) != 0)
 105     {
 106       puts ("rwlockattr_init failed");
 107       return 1;
 108     }
 109
 110   if (pthread_mutexattr_setpshared (&ma, PTHREAD_PROCESS_SHARED) != 0)
 111     {
 112       puts ("mutexattr_setpshared failed");
 113       return 1;
 114     }
 115
 116   if (pthread_mutex_init (m, &ma) != 0)
 117     {
 118       puts ("mutex_init failed");
 119       return 1;
 120     }
 121
 122   /* Lock the mutex.  */
 123   if (pthread_mutex_lock (m) != 0)
 124     {
 125       puts ("mutex_lock failed");
 126       return 1;
 127     }
 128
 129   puts ("going to fork now");
 130   pid = fork ();
 131   if (pid == -1)
 132     {
 133       puts ("fork failed");
 134       return 1;
 135     }
 136   else if (pid == 0)
 137     {
 138       /* Lock the mutex.  */
 139       if (pthread_mutex_lock (m) != 0)
 140         {
 141           puts ("child: mutex_lock failed");
 142           return 1;
 143         }
 144
 145       /* Try to get the rwlock.  */
 146       if (pthread_rwlock_trywrlock (r) == 0)
 147         {
 148           puts ("rwlock_trywrlock succeeded");
 149           return 1;
 150         }
 151
 152       /* Try again.  */
 153       struct timespec ts = { .tv_sec = 0, .tv_nsec = 500000000 };
 154       int e = pthread_rwlock_timedwrlock (r, &ts);
 155       if (e == 0)
 156         {
 157           puts ("rwlock_timedwrlock succeeded");
 158           return 1;
 159         }
 160       if (e != ETIMEDOUT)
 161         {
 162           puts ("rwlock_timedwrlock didn't return ETIMEDOUT");
 163           status = 1;
 164         }
 165
 166       if (pthread_rwlock_tryrdlock (r) == 0)
 167         {
 168           puts ("rwlock_tryrdlock succeeded");
 169           return 1;
 170         }
 171
 172       e = pthread_rwlock_timedrdlock (r, &ts);
 173       if (e == 0)
 174         {
 175           puts ("rwlock_timedrdlock succeeded");
 176           return 1;
 177         }
 178       if (e != ETIMEDOUT)
 179         {
 180           puts ("rwlock_timedrdlock didn't return ETIMEDOUT");
 181           status = 1;
 182         }
 183     }
 184   else
 185     {
 186       /* Lock the rwlock for writing.  */
 187       if (pthread_rwlock_wrlock (r) != 0)
 188         {
 189           puts ("rwlock_wrlock failed");
 190           kill (pid, SIGTERM);
 191           return 1;
 192         }
 193
 194       /* Allow the child to run.  */
 195       if (pthread_mutex_unlock (m) != 0)
 196         {
 197           puts ("mutex_unlock failed");
 198           kill (pid, SIGTERM);
 199           return 1;
 200         }
 201
 202       /* Just wait for the child.  */
 203       if (TEMP_FAILURE_RETRY (waitpid (pid, &status, 0)) != pid)
 204         {
 205           puts ("waitpid failed");
 206           kill (pid, SIGTERM);
 207           return 1;
 208         }
 209     }
 210
 211   return status;
 212 #endif
 213 }
 214
 215 #define TEST_FUNCTION do_test ()
 216 #include "../test-skeleton.c"