1 /* $NetBSD: rpc_dtablesize.c,v 1.14 1998/11/15 17:32:43 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2009, Sun Microsystems, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 * - Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 * - Neither the name of Sun Microsystems, Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #if defined(LIBC_SCCS) && !defined(lint)
32 static char *sccsid2 = "@(#)rpc_dtablesize.c 1.2 87/08/11 Copyr 1987 Sun Micro";
33 static char *sccsid = "@(#)rpc_dtablesize.c 2.1 88/07/29 4.0 RPCSRC";
34 #endif
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37
38 #include "namespace.h"
39 #include <unistd.h>
40 #include "un-namespace.h"
41
42 int _rpc_dtablesize(void); /* XXX */
43
44 /*
45 * Cache the result of getdtablesize(), so we don't have to do an
46 * expensive system call every time.
47 */
48 /*
49 * XXX In FreeBSD 2.x, you can have the maximum number of open file
50 * descriptors be greater than FD_SETSIZE (which us 256 by default).
51 *
52 * Since old programs tend to use this call to determine the first arg
53 * for _select(), having this return > FD_SETSIZE is a Bad Idea(TM)!
54 */
55 int
_rpc_dtablesize(void)56 _rpc_dtablesize(void)
57 {
58 static int size;
59
60 if (size == 0) {
61 size = getdtablesize();
62 if (size > FD_SETSIZE)
63 size = FD_SETSIZE;
64 }
65 return (size);
66 }
67