1 | /* Copyright (C) 1993-2024 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 <hurd.h> |
19 | #include <hurd/id.h> |
20 | #include <string.h> |
21 | |
22 | int |
23 | geteuids (int n, uid_t *uidset) |
24 | { |
25 | error_t err; |
26 | int nuids; |
27 | void *crit; |
28 | |
29 | retry: |
30 | crit = _hurd_critical_section_lock (); |
31 | __mutex_lock (&_hurd_id.lock); |
32 | |
33 | if (err = _hurd_check_ids ()) |
34 | { |
35 | __mutex_unlock (&_hurd_id.lock); |
36 | _hurd_critical_section_unlock (crit); |
37 | if (err == EINTR) |
38 | /* Got a signal while inside an RPC of the critical section, retry again */ |
39 | goto retry; |
40 | return __hurd_fail (err); |
41 | } |
42 | |
43 | nuids = _hurd_id.gen.nuids; |
44 | |
45 | if (n != 0) |
46 | { |
47 | /* Copy the uids onto stack storage and then release the idlock. */ |
48 | uid_t uids[nuids]; |
49 | memcpy (dest: uids, src: _hurd_id.gen.uids, n: sizeof (uids)); |
50 | __mutex_unlock (&_hurd_id.lock); |
51 | _hurd_critical_section_unlock (crit); |
52 | |
53 | /* Now that the lock is released, we can safely copy the |
54 | uid set into the user's array, which might fault. */ |
55 | if (nuids > n) |
56 | nuids = n; |
57 | memcpy (dest: uidset, src: uids, n: nuids * sizeof (uid_t)); |
58 | } |
59 | else |
60 | { |
61 | __mutex_unlock (&_hurd_id.lock); |
62 | _hurd_critical_section_unlock (crit); |
63 | } |
64 | |
65 | return nuids; |
66 | } |
67 | |
68 | /* XXX Remove this alias when we bump the libc soname. */ |
69 | |
70 | #ifdef SHARED |
71 | weak_alias (geteuids, __getuids) |
72 | #endif |
73 | |