/* Test of ftello() function.

   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 <stdio.h>

#include <errno.h>

#include <unistd.h>

#include "macros.h"

int

main (int argc, char **argv)

{

  const char *filename = argv[1];

  /* Test that ftello() sets errno if someone else closes the stream

     fd behind the back of stdio.  */

  {

    FILE *fp = fopen (filename, "r");

    ASSERT (fp != NULL);

    setvbuf (fp, NULL, _IONBF, 0);

    ASSERT (close (fileno (fp)) == 0);

    errno = 0;

    ASSERT (ftello (fp) == (off_t)-1);

    ASSERT (errno == EBADF);

    fclose (fp);

  }

  /* Test that ftello() sets errno if the stream was constructed with

     an invalid file descriptor.  */

  {

    FILE *fp = fdopen (-1, "w");

    if (fp != NULL)

      {

        errno = 0;

        ASSERT (ftello (fp) == (off_t)-1);

        ASSERT (errno == EBADF);

        fclose (fp);

      }

  }

  {

    FILE *fp;

    close (99);

    fp = fdopen (99, "w");

    if (fp != NULL)

      {

        errno = 0;

        ASSERT (ftello (fp) == (off_t)-1);

        ASSERT (errno == EBADF);

        fclose (fp);

      }

  }

  return 0;

}