/* Test changing to a directory named by a file descriptor.

   Copyright (C) 2009-2017 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 <http://www.gnu.org/licenses/>.  */

/* Written by Eric Blake <ebb9@byu.net>, 2009.  */

#include <config.h>

#include <unistd.h>

#include "signature.h"

SIGNATURE_CHECK (fchdir, int, (int));

#include <errno.h>

#include <fcntl.h>

#include <stdlib.h>

#include <string.h>

#include "cloexec.h"

#include "macros.h"

int

main (void)

{

  char *cwd;

  int fd;

  int i;

  cwd = getcwd (NULL, 0);

  ASSERT (cwd);

  fd = open (".", O_RDONLY);

  ASSERT (0 <= fd);

  /* Test behaviour for invalid file descriptors.  */

  {

    errno = 0;

    ASSERT (fchdir (-1) == -1);

    ASSERT (errno == EBADF);

  }

  {

    close (99);

    errno = 0;

    ASSERT (fchdir (99) == -1);

    ASSERT (errno == EBADF);

  }

  /* Check for other failure cases.  */

  {

    int bad_fd = open ("/dev/null", O_RDONLY);

    ASSERT (0 <= bad_fd);

    errno = 0;

    ASSERT (fchdir (bad_fd) == -1);

    ASSERT (errno == ENOTDIR);

    ASSERT (close (bad_fd) == 0);

  }

  /* Repeat test twice, once in '.' and once in '..'.  */

  for (i = 0; i < 2; i++)

    {

      ASSERT (chdir (&".."[1 - i]) == 0);

      ASSERT (fchdir (fd) == 0);

      {

        size_t len = strlen (cwd) + 1;

        char *new_dir = malloc (len);

        ASSERT (new_dir);

        ASSERT (getcwd (new_dir, len) == new_dir);

        ASSERT (strcmp (cwd, new_dir) == 0);

        free (new_dir);

      }

      /* For second iteration, use a cloned fd, to ensure that dup

         remembers whether an fd was associated with a directory.  */

      if (!i)

        {

          int new_fd = dup (fd);

          ASSERT (0 <= new_fd);

          ASSERT (close (fd) == 0);

          ASSERT (dup2 (new_fd, fd) == fd);

          ASSERT (close (new_fd) == 0);

          ASSERT (dup_cloexec (fd) == new_fd);

          ASSERT (dup2 (new_fd, fd) == fd);

          ASSERT (close (new_fd) == 0);

          ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, new_fd) == new_fd);

          ASSERT (close (fd) == 0);

          ASSERT (fcntl (new_fd, F_DUPFD, fd) == fd);

          ASSERT (close (new_fd) == 0);

#if GNULIB_TEST_DUP3

          ASSERT (dup3 (fd, new_fd, 0) == new_fd);

          ASSERT (dup3 (new_fd, fd, 0) == fd);

          ASSERT (close (new_fd) == 0);

#endif

        }

    }

  free (cwd);

  return 0;

}