1 /* $NetBSD: sysconf.c,v 1.5 1997/07/21 14:07:35 jtc Exp $ */ 2 3 /*- 4 * Copyright (c) 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Sean Eric Fagan of Cygnus Support. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94"; 43 #else 44 __RCSID("$NetBSD: sysconf.c,v 1.5 1997/07/21 14:07:35 jtc Exp $"); 45 #endif 46 #endif /* LIBC_SCCS and not lint */ 47 48 #include "namespace.h" 49 #include <sys/param.h> 50 #include <sys/sysctl.h> 51 #include <sys/time.h> 52 #include <sys/resource.h> 53 54 #include <errno.h> 55 #include <unistd.h> 56 57 #ifdef __weak_alias 58 __weak_alias(sysconf,_sysconf); 59 #endif 60 61 /* 62 * sysconf -- 63 * get configurable system variables. 64 * 65 * XXX 66 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 67 * not change during the lifetime of the calling process. This would seem 68 * to require that any change to system limits kill all running processes. 69 * A workaround might be to cache the values when they are first retrieved 70 * and then simply return the cached value on subsequent calls. This is 71 * less useful than returning up-to-date values, however. 72 */ 73 long 74 sysconf(name) 75 int name; 76 { 77 struct rlimit rl; 78 size_t len; 79 int mib[2], value; 80 81 len = sizeof(value); 82 83 switch (name) { 84 /* 1003.1 */ 85 case _SC_ARG_MAX: 86 mib[0] = CTL_KERN; 87 mib[1] = KERN_ARGMAX; 88 break; 89 case _SC_CHILD_MAX: 90 return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur); 91 case _SC_CLK_TCK: 92 return (CLK_TCK); 93 case _SC_JOB_CONTROL: 94 mib[0] = CTL_KERN; 95 mib[1] = KERN_JOB_CONTROL; 96 goto yesno; 97 case _SC_NGROUPS_MAX: 98 mib[0] = CTL_KERN; 99 mib[1] = KERN_NGROUPS; 100 break; 101 case _SC_OPEN_MAX: 102 return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur); 103 case _SC_STREAM_MAX: 104 mib[0] = CTL_USER; 105 mib[1] = USER_STREAM_MAX; 106 break; 107 case _SC_TZNAME_MAX: 108 mib[0] = CTL_USER; 109 mib[1] = USER_TZNAME_MAX; 110 break; 111 case _SC_SAVED_IDS: 112 mib[0] = CTL_KERN; 113 mib[1] = KERN_SAVED_IDS; 114 goto yesno; 115 case _SC_VERSION: 116 mib[0] = CTL_KERN; 117 mib[1] = KERN_POSIX1; 118 break; 119 120 /* 1003.2 */ 121 case _SC_BC_BASE_MAX: 122 mib[0] = CTL_USER; 123 mib[1] = USER_BC_BASE_MAX; 124 break; 125 case _SC_BC_DIM_MAX: 126 mib[0] = CTL_USER; 127 mib[1] = USER_BC_DIM_MAX; 128 break; 129 case _SC_BC_SCALE_MAX: 130 mib[0] = CTL_USER; 131 mib[1] = USER_BC_SCALE_MAX; 132 break; 133 case _SC_BC_STRING_MAX: 134 mib[0] = CTL_USER; 135 mib[1] = USER_BC_STRING_MAX; 136 break; 137 case _SC_COLL_WEIGHTS_MAX: 138 mib[0] = CTL_USER; 139 mib[1] = USER_COLL_WEIGHTS_MAX; 140 break; 141 case _SC_EXPR_NEST_MAX: 142 mib[0] = CTL_USER; 143 mib[1] = USER_EXPR_NEST_MAX; 144 break; 145 case _SC_LINE_MAX: 146 mib[0] = CTL_USER; 147 mib[1] = USER_LINE_MAX; 148 break; 149 case _SC_RE_DUP_MAX: 150 mib[0] = CTL_USER; 151 mib[1] = USER_RE_DUP_MAX; 152 break; 153 case _SC_2_VERSION: 154 mib[0] = CTL_USER; 155 mib[1] = USER_POSIX2_VERSION; 156 break; 157 case _SC_2_C_BIND: 158 mib[0] = CTL_USER; 159 mib[1] = USER_POSIX2_C_BIND; 160 goto yesno; 161 case _SC_2_C_DEV: 162 mib[0] = CTL_USER; 163 mib[1] = USER_POSIX2_C_DEV; 164 goto yesno; 165 case _SC_2_CHAR_TERM: 166 mib[0] = CTL_USER; 167 mib[1] = USER_POSIX2_CHAR_TERM; 168 goto yesno; 169 case _SC_2_FORT_DEV: 170 mib[0] = CTL_USER; 171 mib[1] = USER_POSIX2_FORT_DEV; 172 goto yesno; 173 case _SC_2_FORT_RUN: 174 mib[0] = CTL_USER; 175 mib[1] = USER_POSIX2_FORT_RUN; 176 goto yesno; 177 case _SC_2_LOCALEDEF: 178 mib[0] = CTL_USER; 179 mib[1] = USER_POSIX2_LOCALEDEF; 180 goto yesno; 181 case _SC_2_SW_DEV: 182 mib[0] = CTL_USER; 183 mib[1] = USER_POSIX2_SW_DEV; 184 goto yesno; 185 case _SC_2_UPE: 186 mib[0] = CTL_USER; 187 mib[1] = USER_POSIX2_UPE; 188 yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) 189 return (-1); 190 if (value == 0) 191 return (-1); 192 return (value); 193 break; 194 default: 195 errno = EINVAL; 196 return (-1); 197 } 198 return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); 199 } 200