1/*
2 * Copyright (c) 1995-2001 Kungliga Tekniska Högskolan
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#include <config.h>
35
36#include "roken.h"
37
38#ifdef HAVE_SYS_TYPES_H
39#include <sys/types.h>
40#endif
41#ifdef TIME_WITH_SYS_TIME
42#include <sys/time.h>
43#include <time.h>
44#elif defined(HAVE_SYS_TIME_H)
45#include <sys/time.h>
46#else
47#include <time.h>
48#endif
49#ifdef HAVE_SYS_PARAM_H
50#include <sys/param.h>
51#endif
52#ifdef HAVE_UNISTD_H
53#include <unistd.h>
54#endif
55
56#ifdef HAVE_SYS_RESOURCE_H
57#include <sys/resource.h>
58#endif
59
60#ifdef HAVE_SYS_SYSCTL_H
61#include <sys/sysctl.h>
62#endif
63
64ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
65getdtablesize(void)
66{
67  int files = -1;
68#if defined(HAVE_SYSCONF) && defined(_SC_OPEN_MAX)
69  files = sysconf(_SC_OPEN_MAX);
70#else /* !defined(HAVE_SYSCONF) */
71#if defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE)
72  struct rlimit res;
73  if (getrlimit(RLIMIT_NOFILE, &res) == 0)
74    files = res.rlim_cur;
75#else /* !definded(HAVE_GETRLIMIT) */
76#if defined(HAVE_SYSCTL) && defined(CTL_KERN) && defined(KERN_MAXFILES)
77  int mib[2];
78  size_t len;
79
80  mib[0] = CTL_KERN;
81  mib[1] = KERN_MAXFILES;
82  len = sizeof(files);
83  sysctl(&mib, 2, &files, sizeof(files), NULL, 0);
84#endif /* defined(HAVE_SYSCTL) */
85#endif /* !definded(HAVE_GETRLIMIT) */
86#endif /* !defined(HAVE_SYSCONF) */
87
88#ifdef OPEN_MAX
89  if (files < 0)
90    files = OPEN_MAX;
91#endif
92
93#ifdef NOFILE
94  if (files < 0)
95    files = NOFILE;
96#endif
97
98  return files;
99}
100