crypto/external/bsd/heimdal/dist/lib/roken/getdtablesize.c

   1 /*      $NetBSD: getdtablesize.c,v 1.1.1.1 2011/04/13 18:15:41 elric Exp $      */
   2
   3 /*
   4  * Copyright (c) 1995-2001 Kungliga Tekniska Högskolan
   5  * (Royal Institute of Technology, Stockholm, Sweden).
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * 3. Neither the name of the Institute nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <config.h>
  37
  38 #include <krb5/roken.h>
  39
  40 #ifdef HAVE_SYS_TYPES_H
  41 #include <sys/types.h>
  42 #endif
  43 #ifdef TIME_WITH_SYS_TIME
  44 #include <sys/time.h>
  45 #include <time.h>
  46 #elif defined(HAVE_SYS_TIME_H)
  47 #include <sys/time.h>
  48 #else
  49 #include <time.h>
  50 #endif
  51 #ifdef HAVE_SYS_PARAM_H
  52 #include <sys/param.h>
  53 #endif
  54 #ifdef HAVE_UNISTD_H
  55 #include <unistd.h>
  56 #endif
  57
  58 #ifdef HAVE_SYS_RESOURCE_H
  59 #include <sys/resource.h>
  60 #endif
  61
  62 #ifdef HAVE_SYS_SYSCTL_H
  63 #include <sys/sysctl.h>
  64 #endif
  65
  66 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
  67 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 }