1 /* Copyright (C) 1991-2022 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 <errno.h>
19 #include <unistd.h>
20 #include <hurd.h>
21 #include <hurd/fd.h>
22 #include <hurd/resource.h>
23 
24 /* Return the maximum number of file descriptors the current process
25    could possibly have (until it raises the resource limit).  */
26 int
__getdtablesize(void)27 __getdtablesize (void)
28 {
29   rlim_t limit;
30 
31   HURD_CRITICAL_BEGIN;
32   __mutex_lock (&_hurd_rlimit_lock);
33   limit = _hurd_rlimits[RLIMIT_NOFILE].rlim_cur;
34   __mutex_unlock (&_hurd_rlimit_lock);
35   HURD_CRITICAL_END;
36 
37   /* RLIM_INFINITY is not meaningful to our caller.  -1 is a good choice
38      because `sysconf (_SC_OPEN_MAX)' calls us, and -1 from sysconf means
39      "no determinable limit".  */
40   return limit == RLIM_INFINITY ? -1 : (int) limit;
41 }
42 
43 weak_alias (__getdtablesize, getdtablesize)
44