/* Test truncating a file.

   Copyright (C) 2011-2019 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include <unistd.h>

#include "signature.h"

SIGNATURE_CHECK (ftruncate, int, (int, off_t));

#include <errno.h>

#include <fcntl.h>

#include "macros.h"

int

main (int argc, char *argv[])

{

  const char *filename = argv[1];

  /* Test behaviour for invalid file descriptors.  */

  {

    errno = 0;

    ASSERT (ftruncate (-1, 0) == -1);

    ASSERT (errno == EBADF);

  }

  {

    close (99);

    errno = 0;

    ASSERT (ftruncate (99, 0) == -1);

    ASSERT (errno == EBADF);

  }

  /* Test behaviour for read-only file descriptors.  */

  {

    int fd = open (filename, O_RDONLY);

    ASSERT (fd >= 0);

    errno = 0;

    ASSERT (ftruncate (fd, 0) == -1);

    ASSERT (errno == EBADF || errno == EINVAL

            || errno == EACCES /* seen on mingw */

           );

    close (fd);

  }

  return 0;

}