nptl/tst-cond6.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 <errno.h>
  21 #include <pthread.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <time.h>
  26 #include <unistd.h>
  27 #include <sys/mman.h>
  28 #include <sys/time.h>
  29 #include <sys/wait.h>
  30
  31
  32 int *condition;
  33
  34
  35 int
  36 main (void)
  37 {
  38   size_t ps = sysconf (_SC_PAGESIZE);
  39   char tmpfname[] = "/tmp/tst-cond6.XXXXXX";
  40   char data[ps];
  41   void *mem;
  42   int fd;
  43   pthread_mutexattr_t ma;
  44   pthread_mutex_t *mut1;
  45   pthread_mutex_t *mut2;
  46   pthread_condattr_t ca;
  47   pthread_cond_t *cond;
  48   pid_t pid;
  49   int result = 0;
  50
  51   fd = mkstemp (tmpfname);
  52   if (fd == -1)
  53     {
  54       printf ("cannot open temporary file: %m\n");
  55       exit (1);
  56     }
  57
  58   /* Make sure it is always removed.  */
  59   unlink (tmpfname);
  60
  61   /* Create one page of data.  */
  62   memset (data, '\0', ps);
  63
  64   /* Write the data to the file.  */
  65   if (write (fd, data, ps) != ps)
  66     {
  67       puts ("short write");
  68       exit (1);
  69     }
  70
  71   mem = mmap (NULL, ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
  72   if (mem == MAP_FAILED)
  73     {
  74       printf ("mmap failed: %m\n");
  75       exit (1);
  76     }
  77
  78   mut1 = (pthread_mutex_t *) (((uintptr_t) mem
  79                                + __alignof (pthread_mutex_t))
  80                               & ~(__alignof (pthread_mutex_t) - 1));
  81   mut2 = mut1 + 1;
  82
  83   cond = (pthread_cond_t *) (((uintptr_t) (mut2 + 1)
  84                               + __alignof (pthread_cond_t))
  85                              & ~(__alignof (pthread_cond_t) - 1));
  86
  87   condition = (int *) (((uintptr_t) (cond + 1) + __alignof (int))
  88                        & ~(__alignof (int) - 1));
  89
  90   if (pthread_mutexattr_init (&ma) != 0)
  91     {
  92       puts ("mutexattr_init failed");
  93       exit (1);
  94     }
  95
  96   if (pthread_mutexattr_setpshared (&ma, PTHREAD_PROCESS_SHARED) != 0)
  97     {
  98       puts ("mutexattr_setpshared failed");
  99       exit (1);
 100     }
 101
 102   if (pthread_mutex_init (mut1, &ma) != 0)
 103     {
 104       puts ("1st mutex_init failed");
 105       exit (1);
 106     }
 107
 108   if (pthread_mutex_init (mut2, &ma) != 0)
 109     {
 110       puts ("2nd mutex_init failed");
 111       exit (1);
 112     }
 113
 114   if (pthread_condattr_init (&ca) != 0)
 115     {
 116       puts ("condattr_init failed");
 117       exit (1);
 118     }
 119
 120   if (pthread_condattr_setpshared (&ca, PTHREAD_PROCESS_SHARED) != 0)
 121     {
 122       puts ("condattr_setpshared failed");
 123       exit (1);
 124     }
 125
 126   if (pthread_cond_init (cond, &ca) != 0)
 127     {
 128       puts ("cond_init failed");
 129       exit (1);
 130     }
 131
 132   if (pthread_mutex_lock (mut1) != 0)
 133     {
 134       puts ("parent: 1st mutex_lock failed");
 135       exit (1);
 136     }
 137
 138   puts ("going to fork now");
 139   pid = fork ();
 140   if (pid == -1)
 141     {
 142       puts ("fork failed");
 143       exit (1);
 144     }
 145   else if (pid == 0)
 146     {
 147       struct timespec ts;
 148       struct timeval tv;
 149
 150       if (pthread_mutex_lock (mut2) != 0)
 151         {
 152           puts ("child: mutex_lock failed");
 153           exit (1);
 154         }
 155
 156       if (pthread_mutex_unlock (mut1) != 0)
 157         {
 158           puts ("child: 1st mutex_unlock failed");
 159           exit (1);
 160         }
 161
 162       /* Waiting for the condition will fail.  But we want the timeout
 163          here.  */
 164       if (gettimeofday (&tv, NULL) != 0)
 165         {
 166           puts ("gettimeofday failed");
 167           exit (1);
 168         }
 169
 170       TIMEVAL_TO_TIMESPEC (&tv, &ts);
 171       ts.tv_nsec += 500000000;
 172       if (ts.tv_nsec >= 1000000000)
 173         {
 174           ts.tv_nsec -= 1000000000;
 175           ++ts.tv_sec;
 176         }
 177
 178       do
 179         if (pthread_cond_timedwait (cond, mut2, &ts) != 0)
 180           {
 181             puts ("child: cond_wait failed");
 182             exit (1);
 183           }
 184       while (*condition == 0);
 185
 186       if (pthread_mutex_unlock (mut2) != 0)
 187         {
 188           puts ("child: 2nd mutex_unlock failed");
 189           exit (1);
 190         }
 191
 192       puts ("child done");
 193     }
 194   else
 195     {
 196       int status;
 197
 198       if (pthread_mutex_lock (mut1) != 0)
 199         {
 200           puts ("parent: 2nd mutex_lock failed");
 201           exit (1);
 202         }
 203
 204       if (pthread_mutex_lock (mut2) != 0)
 205         {
 206           puts ("parent: 3rd mutex_lock failed");
 207           exit (1);
 208         }
 209
 210       if (pthread_cond_signal (cond) != 0)
 211         {
 212           puts ("parent: cond_signal failed");
 213           exit (1);
 214         }
 215
 216       *condition = 1;
 217
 218       if (pthread_mutex_unlock (mut2) != 0)
 219         {
 220           puts ("parent: mutex_unlock failed");
 221           exit (1);
 222         }
 223
 224       puts ("waiting for child");
 225
 226       waitpid (pid, &status, 0);
 227       result |= status;
 228
 229       puts ("parent done");
 230     }
 231
 232  return result;
 233 }