1/*
2 * Copyright (c) 1995-2001 Kungliga Tekniska H�gskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifdef HAVE_CONFIG_H
35#include <config.h>
36RCSID("$Id: getdtablesize.c,v 1.11 2001/06/20 00:00:38 joda Exp $");
37#endif
38
39#include "roken.h"
40
41#ifdef HAVE_SYS_TYPES_H
42#include <sys/types.h>
43#endif
44#ifdef TIME_WITH_SYS_TIME
45#include <sys/time.h>
46#include <time.h>
47#elif defined(HAVE_SYS_TIME_H)
48#include <sys/time.h>
49#else
50#include <time.h>
51#endif
52#ifdef HAVE_SYS_PARAM_H
53#include <sys/param.h>
54#endif
55#ifdef HAVE_UNISTD_H
56#include <unistd.h>
57#endif
58
59#ifdef HAVE_SYS_RESOURCE_H
60#include <sys/resource.h>
61#endif
62
63#ifdef HAVE_SYS_SYSCTL_H
64#include <sys/sysctl.h>
65#endif
66
67int getdtablesize(void)
68{
69 int files = -1;
70#if defined(HAVE_SYSCONF) && defined(_SC_OPEN_MAX)
71 files = sysconf(_SC_OPEN_MAX);
72#else /* !defined(HAVE_SYSCONF) */
73#if defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE)
74 struct rlimit res;
75 if (getrlimit(RLIMIT_NOFILE, &res) == 0)
76 files = res.rlim_cur;
77#else /* !definded(HAVE_GETRLIMIT) */
78#if defined(HAVE_SYSCTL) && defined(CTL_KERN) && defined(KERN_MAXFILES)
79 int mib[2];
80 size_t len;
81
82 mib[0] = CTL_KERN;
83 mib[1] = KERN_MAXFILES;
84 len = sizeof(files);
85 sysctl(&mib, 2, &files, sizeof(files), NULL, 0);
86#endif /* defined(HAVE_SYSCTL) */
87#endif /* !definded(HAVE_GETRLIMIT) */
88#endif /* !defined(HAVE_SYSCONF) */
89
90#ifdef OPEN_MAX
91 if (files < 0)
92 files = OPEN_MAX;
93#endif
94
95#ifdef NOFILE
96 if (files < 0)
97 files = NOFILE;
98#endif
99
100 return files;
101}