mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-22 19:00:07 +00:00
145 lines
2.9 KiB
C
145 lines
2.9 KiB
C
/* Copyright (C) 2002-2014 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <errno.h>
|
|
#include <semaphore.h>
|
|
#include <stdint.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/wait.h>
|
|
|
|
|
|
int
|
|
do_test (void)
|
|
{
|
|
size_t ps = sysconf (_SC_PAGESIZE);
|
|
char tmpfname[] = "/tmp/tst-sem3.XXXXXX";
|
|
char data[ps];
|
|
void *mem;
|
|
int fd;
|
|
sem_t *s;
|
|
pid_t pid;
|
|
char *p;
|
|
|
|
fd = mkstemp (tmpfname);
|
|
if (fd == -1)
|
|
{
|
|
printf ("cannot open temporary file: %m\n");
|
|
return 1;
|
|
}
|
|
|
|
/* Make sure it is always removed. */
|
|
unlink (tmpfname);
|
|
|
|
/* Create one page of data. */
|
|
memset (data, '\0', ps);
|
|
|
|
/* Write the data to the file. */
|
|
if (write (fd, data, ps) != (ssize_t) ps)
|
|
{
|
|
puts ("short write");
|
|
return 1;
|
|
}
|
|
|
|
mem = mmap (NULL, ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
|
|
if (mem == MAP_FAILED)
|
|
{
|
|
printf ("mmap failed: %m\n");
|
|
return 1;
|
|
}
|
|
|
|
s = (sem_t *) (((uintptr_t) mem + __alignof (sem_t))
|
|
& ~(__alignof (sem_t) - 1));
|
|
p = (char *) (s + 1);
|
|
|
|
if (sem_init (s, 1, 1) == -1)
|
|
{
|
|
puts ("init failed");
|
|
return 1;
|
|
}
|
|
|
|
if (TEMP_FAILURE_RETRY (sem_wait (s)) == -1)
|
|
{
|
|
puts ("1st wait failed");
|
|
return 1;
|
|
}
|
|
|
|
errno = 0;
|
|
if (TEMP_FAILURE_RETRY (sem_trywait (s)) != -1)
|
|
{
|
|
puts ("trywait succeeded");
|
|
return 1;
|
|
}
|
|
else if (errno != EAGAIN)
|
|
{
|
|
puts ("trywait didn't return EAGAIN");
|
|
return 1;
|
|
}
|
|
|
|
*p = 0;
|
|
|
|
puts ("going to fork now");
|
|
pid = fork ();
|
|
if (pid == -1)
|
|
{
|
|
puts ("fork failed");
|
|
return 1;
|
|
}
|
|
else if (pid == 0)
|
|
{
|
|
/* Play some lock ping-pong. It's our turn to unlock first. */
|
|
if ((*p)++ != 0)
|
|
{
|
|
puts ("child: *p != 0");
|
|
return 1;
|
|
}
|
|
|
|
if (sem_post (s) == -1)
|
|
{
|
|
puts ("child: 1st post failed");
|
|
return 1;
|
|
}
|
|
|
|
puts ("child done");
|
|
}
|
|
else
|
|
{
|
|
if (TEMP_FAILURE_RETRY (sem_wait (s)) == -1)
|
|
{
|
|
printf ("parent: 2nd wait failed: %m\n");
|
|
return 1;
|
|
}
|
|
|
|
if (*p != 1)
|
|
{
|
|
puts ("*p != 1");
|
|
return 1;
|
|
}
|
|
|
|
puts ("parent done");
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define TEST_FUNCTION do_test ()
|
|
#include "../test-skeleton.c"
|