1 /* Copyright (C) 1993-2022 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 <hurd.h>
19 #include <hurd/id.h>
20 #include <string.h>
21
22 int
geteuids(int n,uid_t * uidset)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 (uids, _hurd_id.gen.uids, 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 (uidset, uids, 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