glibc/libio/tst-freopen.c

103 lines
2.5 KiB
C

/* Test freopen with mmap stdio.
Copyright (C) 2002-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
int
main (void)
{
char name[] = "/tmp/tst-freopen.XXXXXX";
const char * const test = "Let's test freopen.\n";
char temp[strlen (test) + 1];
int fd = mkstemp (name);
FILE *f;
if (fd == -1)
{
printf ("%u: cannot open temporary file: %m\n", __LINE__);
exit (1);
}
f = fdopen (fd, "w");
if (f == NULL)
{
printf ("%u: cannot fdopen temporary file: %m\n", __LINE__);
exit (1);
}
fputs (test, f);
fclose (f);
f = fopen (name, "r");
if (f == NULL)
{
printf ("%u: cannot fopen temporary file: %m\n", __LINE__);
exit (1);
}
if (fread (temp, 1, strlen (test), f) != strlen (test))
{
printf ("%u: couldn't read the file back: %m\n", __LINE__);
exit (1);
}
temp [strlen (test)] = '\0';
if (strcmp (test, temp))
{
printf ("%u: read different string than was written:\n%s%s",
__LINE__, test, temp);
exit (1);
}
f = freopen (name, "r+", f);
if (f == NULL)
{
printf ("%u: cannot freopen temporary file: %m\n", __LINE__);
exit (1);
}
if (fseek (f, 0, SEEK_SET) != 0)
{
printf ("%u: couldn't fseek to start: %m\n", __LINE__);
exit (1);
}
if (fread (temp, 1, strlen (test), f) != strlen (test))
{
printf ("%u: couldn't read the file back: %m\n", __LINE__);
exit (1);
}
temp [strlen (test)] = '\0';
if (strcmp (test, temp))
{
printf ("%u: read different string than was written:\n%s%s",
__LINE__, test, temp);
exit (1);
}
fclose (f);
unlink (name);
exit (0);
}