sysdeps/mach/hurd/setgroups.c

   1 /* Copyright (C) 1993, 1994 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <errno.h>
  21 #include <sys/types.h>
  22 #include <grp.h>
  23 #include <hurd.h>
  24 #include <hurd/id.h>
  25
  26 /* Set the group set for the current user to GROUPS (N of them).  */
  27 int
  28 DEFUN(setgroups, (n, groups), size_t n AND CONST gid_t *groups)
  29 {
  30   error_t err;
  31   auth_t newauth;
  32   size_t i;
  33   gid_t new[n];
  34
  35   /* Fault before taking locks.  */
  36   for (i = 0; i < n; ++i)
  37     new[i] = groups[i];
  38
  39   HURD_CRITICAL_BEGIN;
  40   __mutex_lock (&_hurd_id.lock);
  41   err = _hurd_check_ids ();
  42   if (! err)
  43     {
  44       /* Get a new auth port using those IDs.  */
  45       err = __USEPORT (AUTH,
  46                        __auth_makeauth (port, NULL, MACH_MSG_TYPE_COPY_SEND, 0,
  47                                         _hurd_id.gen.uids, _hurd_id.gen.nuids,
  48                                         _hurd_id.aux.uids, _hurd_id.aux.nuids,
  49                                         new, n,
  50                                         _hurd_id.aux.gids, _hurd_id.aux.ngids,
  51                                         &newauth));
  52     }
  53   __mutex_unlock (&_hurd_id.lock);
  54   HURD_CRITICAL_END;
  55
  56   if (err)
  57     return __hurd_fail (err);
  58
  59   /* Install the new auth port and reauthenticate everything.  */
  60   err = __setauth (newauth);
  61   __mach_port_deallocate (__mach_task_self (), newauth);
  62   return err;
  63 }