sysdeps/mach/hurd/dirfd.c

   1 /* dirfd -- Return the file descriptor used by a DIR stream.  Hurd version.
   2    Copyright (C) 1995-2016 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <dirent.h>
  20 #include <dirstream.h>
  21 #include <hurd/fd.h>
  22 #include <errno.h>
  23
  24 int
  25 dirfd (DIR *dirp)
  26 {
  27   int fd;
  28
  29   HURD_CRITICAL_BEGIN;
  30   __mutex_lock (&_hurd_dtable_lock);
  31   for (fd = 0; fd < _hurd_dtablesize; ++fd)
  32     if (_hurd_dtable[fd] == dirp->__fd)
  33       break;
  34   if (fd == _hurd_dtablesize)
  35     {
  36       errno = EINVAL;
  37       fd = -1;
  38     }
  39   __mutex_unlock (&_hurd_dtable_lock);
  40   HURD_CRITICAL_END;
  41
  42   return fd;
  43 }