1 /* Copyright (C) 1999-2022 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 Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the 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    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <unistd.h>
19 
20 #include <hurd.h>
21 #include <hurd/fd.h>
22 #include <hurd/port.h>
23 
24 /* Change the current root directory to FD.  */
25 int
fchroot(int fd)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, ".", 0, 0);
34 			  dir == MACH_PORT_NULL ? errno : 0;
35 			}));
36 
37   if (! err)
38     {
39       file_t root;
40 
41       /* Prevent going through DIR's ..  */
42       err = __file_reparent (dir, MACH_PORT_NULL, &root);
43       __mach_port_deallocate (__mach_task_self (), dir);
44       if (! err)
45 	_hurd_port_set (&_hurd_ports[INIT_PORT_CRDIR], root);
46     }
47 
48   return err ? __hurd_fail (err) : 0;
49 }
50