1/* `group_member' -- test if process is in a given group. Hurd version.
2 Copyright (C) 1993-2022 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 <unistd.h>
21#include <hurd.h>
22#include <hurd/id.h>
23
24int
25__group_member (gid_t gid)
26{
27 int member = 0;
28 error_t err;
29 void *crit;
30
31retry:
32 crit = _hurd_critical_section_lock ();
33 __mutex_lock (&_hurd_id.lock);
34
35 err = _hurd_check_ids ();
36 if (! err)
37 {
38 size_t i;
39 for (i = 0; i < _hurd_id.gen.ngids; ++i)
40 if (_hurd_id.gen.gids[i] == gid)
41 {
42 member = 1;
43 break;
44 }
45 }
46
47 __mutex_unlock (&_hurd_id.lock);
48 _hurd_critical_section_unlock (crit);
49 if (err == EINTR)
50 /* Got a signal while inside an RPC of the critical section, retry again */
51 goto retry;
52
53 if (err)
54 __hurd_fail (err);
55 return member;
56}
57
58weak_alias (__group_member, group_member)
59

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