diff options
Diffstat (limited to 'hurd/getuids.c')
-rw-r--r-- | hurd/getuids.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/hurd/getuids.c b/hurd/getuids.c new file mode 100644 index 0000000..9a62f65 --- /dev/null +++ b/hurd/getuids.c @@ -0,0 +1,63 @@ +/* Copyright (C) 1993, 1994 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <hurd.h> +#include <hurd/id.h> +#include <string.h> + +int +__getuids (int n, uid_t *uidset) +{ + error_t err; + int nuids; + void *crit; + + crit = _hurd_critical_section_lock (); + __mutex_lock (&_hurd_id.lock); + + if (err = _hurd_check_ids ()) + { + __mutex_unlock (&_hurd_id.lock); + _hurd_critical_section_unlock (crit); + return __hurd_fail (err); + } + + nuids = _hurd_id.gen.nuids; + + if (n != 0) + { + /* Copy the uids onto stack storage and then release the idlock. */ + uid_t uids[nuids]; + memcpy (uids, _hurd_id.gen.uids, sizeof (uids)); + __mutex_unlock (&_hurd_id.lock); + _hurd_critical_section_unlock (crit); + + /* Now that the lock is released, we can safely copy the + uid set into the user's array, which might fault. */ + if (nuids > n) + nuids = n; + memcpy (uidset, uids, nuids * sizeof (uid_t)); + } + else + { + __mutex_unlock (&_hurd_id.lock); + _hurd_critical_section_unlock (crit); + } + + return nuids; +} |