hurd/fchroot.c

   1 /* Copyright (C) 1991, 92, 93, 94, 95, 96, 97 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <unistd.h>
  20 #include <hurd.h>
  21 #include <hurd/fd.h>
  22 #include <fcntl.h>
  23
  24 /* Change the current root directory to FD.  */
  25 int
  26 fchroot (int fd)
  27 {
  28   error_t err;
  29   file_t dir;
  30
  31   err = HURD_DPORT_USE (fd,
  32                         ({
  33                           dir = __file_name_lookup_under (port, "", O_EXEC, 0);
  34                           dir == MACH_PORT_NULL ? errno : 0;
  35                         }));
  36
  37   if (! err)
  38     {
  39       file_t root;
  40       err = __file_reparent (dir, MACH_PORT_NULL, &root);
  41       __mach_port_deallocate (__mach_task_self (), dir);
  42       if (! err)
  43         _hurd_port_set (&_hurd_ports[INIT_PORT_CRDIR], root);
  44     }
  45
  46   return err ? __hurd_fail (err) : 0;
  47 }