sysdeps/mach/hurd/group_member.c

   1 /* `group_member' -- test if process is in a given group.  Hurd version.
   2    Copyright (C) 1993-2024 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 <unistd.h>
  21 #include <hurd.h>
  22 #include <hurd/id.h>
  23
  24 int
  25 __group_member (gid_t gid)
  26 {
  27   int member = 0;
  28   error_t err;
  29   void *crit;
  30
  31 retry:
  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
  58 weak_alias (__group_member, group_member)