1 /* $NetBSD: sysconf.c,v 1.3 1995/03/04 01:56:09 cgd 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 #if defined(LIBC_SCCS) && !defined(lint) 40 #if 0 41 static char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94"; 42 #else 43 static char rcsid[] = "$NetBSD: sysconf.c,v 1.3 1995/03/04 01:56:09 cgd Exp $"; 44 #endif 45 #endif /* LIBC_SCCS and not lint */ 46 47 #include <sys/param.h> 48 #include <sys/sysctl.h> 49 #include <sys/time.h> 50 #include <sys/resource.h> 51 52 #include <errno.h> 53 #include <unistd.h> 54 55 /* 56 * sysconf -- 57 * get configurable system variables. 58 * 59 * XXX 60 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 61 * not change during the lifetime of the calling process. This would seem 62 * to require that any change to system limits kill all running processes. 63 * A workaround might be to cache the values when they are first retrieved 64 * and then simply return the cached value on subsequent calls. This is 65 * less useful than returning up-to-date values, however. 66 */ 67 long 68 sysconf(name) 69 int name; 70 { 71 struct clockinfo clk; 72 struct rlimit rl; 73 size_t len; 74 int mib[2], value; 75 76 len = sizeof(value); 77 78 switch (name) { 79 /* 1003.1 */ 80 case _SC_ARG_MAX: 81 mib[0] = CTL_KERN; 82 mib[1] = KERN_ARGMAX; 83 break; 84 case _SC_CHILD_MAX: 85 return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur); 86 case _SC_CLK_TCK: 87 return (CLK_TCK); 88 case _SC_JOB_CONTROL: 89 mib[0] = CTL_KERN; 90 mib[1] = KERN_JOB_CONTROL; 91 goto yesno; 92 case _SC_NGROUPS_MAX: 93 mib[0] = CTL_KERN; 94 mib[1] = KERN_NGROUPS; 95 break; 96 case _SC_OPEN_MAX: 97 return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur); 98 case _SC_STREAM_MAX: 99 mib[0] = CTL_USER; 100 mib[1] = USER_STREAM_MAX; 101 break; 102 case _SC_TZNAME_MAX: 103 mib[0] = CTL_USER; 104 mib[1] = USER_TZNAME_MAX; 105 break; 106 case _SC_SAVED_IDS: 107 mib[0] = CTL_KERN; 108 mib[1] = KERN_SAVED_IDS; 109 goto yesno; 110 case _SC_VERSION: 111 mib[0] = CTL_KERN; 112 mib[1] = KERN_POSIX1; 113 break; 114 115 /* 1003.2 */ 116 case _SC_BC_BASE_MAX: 117 mib[0] = CTL_USER; 118 mib[1] = USER_BC_BASE_MAX; 119 break; 120 case _SC_BC_DIM_MAX: 121 mib[0] = CTL_USER; 122 mib[1] = USER_BC_DIM_MAX; 123 break; 124 case _SC_BC_SCALE_MAX: 125 mib[0] = CTL_USER; 126 mib[1] = USER_BC_SCALE_MAX; 127 break; 128 case _SC_BC_STRING_MAX: 129 mib[0] = CTL_USER; 130 mib[1] = USER_BC_STRING_MAX; 131 break; 132 case _SC_COLL_WEIGHTS_MAX: 133 mib[0] = CTL_USER; 134 mib[1] = USER_COLL_WEIGHTS_MAX; 135 break; 136 case _SC_EXPR_NEST_MAX: 137 mib[0] = CTL_USER; 138 mib[1] = USER_EXPR_NEST_MAX; 139 break; 140 case _SC_LINE_MAX: 141 mib[0] = CTL_USER; 142 mib[1] = USER_LINE_MAX; 143 break; 144 case _SC_RE_DUP_MAX: 145 mib[0] = CTL_USER; 146 mib[1] = USER_RE_DUP_MAX; 147 break; 148 case _SC_2_VERSION: 149 mib[0] = CTL_USER; 150 mib[1] = USER_POSIX2_VERSION; 151 break; 152 case _SC_2_C_BIND: 153 mib[0] = CTL_USER; 154 mib[1] = USER_POSIX2_C_BIND; 155 goto yesno; 156 case _SC_2_C_DEV: 157 mib[0] = CTL_USER; 158 mib[1] = USER_POSIX2_C_DEV; 159 goto yesno; 160 case _SC_2_CHAR_TERM: 161 mib[0] = CTL_USER; 162 mib[1] = USER_POSIX2_CHAR_TERM; 163 goto yesno; 164 case _SC_2_FORT_DEV: 165 mib[0] = CTL_USER; 166 mib[1] = USER_POSIX2_FORT_DEV; 167 goto yesno; 168 case _SC_2_FORT_RUN: 169 mib[0] = CTL_USER; 170 mib[1] = USER_POSIX2_FORT_RUN; 171 goto yesno; 172 case _SC_2_LOCALEDEF: 173 mib[0] = CTL_USER; 174 mib[1] = USER_POSIX2_LOCALEDEF; 175 goto yesno; 176 case _SC_2_SW_DEV: 177 mib[0] = CTL_USER; 178 mib[1] = USER_POSIX2_SW_DEV; 179 goto yesno; 180 case _SC_2_UPE: 181 mib[0] = CTL_USER; 182 mib[1] = USER_POSIX2_UPE; 183 yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) 184 return (-1); 185 if (value == 0) 186 return (-1); 187 return (value); 188 break; 189 default: 190 errno = EINVAL; 191 return (-1); 192 } 193 return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); 194 } 195