1/* Make a link between file names relative to open directories. Hurd version.
2 Copyright (C) 2006-2024 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 <https://www.gnu.org/licenses/>. */
18
19#include <errno.h>
20#include <fcntl.h>
21#include <stddef.h>
22#include <unistd.h>
23#include <hurd.h>
24#include <hurd/fd.h>
25
26#include <linkat_common.h>
27
28/* Make a link to FROM relative to FROMFD called TO relative to TOFD. */
29int
30__linkat_common (int fromfd, const char *from, int tofd, const char *to, int at_flags, int flags)
31{
32 error_t err;
33 file_t oldfile, linknode, todir;
34 char *toname;
35
36 oldfile = __file_name_lookup_at (fromfd, at_flags, from, flags, 0);
37 if (oldfile == MACH_PORT_NULL)
38 return -1;
39
40 /* The file_getlinknode RPC returns the port that should be passed to
41 the receiving filesystem (the one containing TODIR) in dir_link. */
42
43 err = __file_getlinknode (oldfile, &linknode);
44 __mach_port_deallocate (__mach_task_self (), oldfile);
45 if (err)
46 return __hurd_fail (err);
47
48 todir = __file_name_split_at (tofd, to, &toname);
49 if (todir != MACH_PORT_NULL)
50 {
51 err = __dir_link (todir, linknode, toname, 1);
52 __mach_port_deallocate (__mach_task_self (), todir);
53 }
54 __mach_port_deallocate (__mach_task_self (), linknode);
55 if (todir == MACH_PORT_NULL)
56 return -1;
57
58 if (err)
59 return __hurd_fail (err);
60 return 0;
61}
62
63int
64__linkat (int fromfd, const char *from, int tofd, const char *to, int at_flags)
65{
66 /* POSIX says linkat doesn't follow symlinks by default, so pass
67 O_NOLINK. That can be overridden by AT_SYMLINK_FOLLOW in FLAGS. */
68 return __linkat_common (fromfd, from, tofd, to, at_flags, flags: O_NOLINK);
69}
70weak_alias (__linkat, linkat)
71

source code of glibc/sysdeps/mach/hurd/linkat.c