/* Test that openat works.

   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 <fcntl.h>

#include "signature.h"

SIGNATURE_CHECK (openat, int, (int, char const *, int, ...));

#include <errno.h>

#include <stdarg.h>

#include <stdbool.h>

#include <stdio.h>

#include <unistd.h>

#include "macros.h"

#define BASE "test-openat.t"

#include "test-open.h"

static int dfd = AT_FDCWD;

/* Wrapper around openat to test open behavior.  */

static int

do_open (char const *name, int flags, ...)

{

  if (flags & O_CREAT)

    {

      mode_t mode = 0;

      va_list arg;

      va_start (arg, flags);

      /* We have to use PROMOTED_MODE_T instead of mode_t, otherwise GCC 4

         creates crashing code when 'mode_t' is smaller than 'int'.  */

      mode = va_arg (arg, PROMOTED_MODE_T);

      va_end (arg);

      return openat (dfd, name, flags, mode);

    }

  return openat (dfd, name, flags);

}

int

main (int argc _GL_UNUSED, char *argv[])

{

  int result;

  /* Test behaviour for invalid file descriptors.  */

  {

    errno = 0;

    ASSERT (openat (-1, "foo", O_RDONLY) == -1);

    ASSERT (errno == EBADF);

  }

  {

    close (99);

    errno = 0;

    ASSERT (openat (99, "foo", O_RDONLY) == -1);

    ASSERT (errno == EBADF);

  }

  /* Basic checks.  */

  result = test_open (do_open, false);

  dfd = open (".", O_RDONLY);

  ASSERT (0 <= dfd);

  ASSERT (test_open (do_open, false) == result);

  ASSERT (close (dfd) == 0);

  /* Check that even when *-safer modules are in use, plain openat can

     land in fd 0.  Do this test last, since it is destructive to

     stdin.  */

  ASSERT (close (STDIN_FILENO) == 0);

  ASSERT (openat (AT_FDCWD, ".", O_RDONLY) == STDIN_FILENO);

  {

    dfd = open (".", O_RDONLY);

    ASSERT (STDIN_FILENO < dfd);

    ASSERT (chdir ("..") == 0);

    ASSERT (close (STDIN_FILENO) == 0);

    ASSERT (openat (dfd, ".", O_RDONLY) == STDIN_FILENO);

    ASSERT (close (dfd) == 0);

  }

  return result;

}