sysconf.c revision 6171
11573Srgrimes/*- 21573Srgrimes * Copyright (c) 1993 31573Srgrimes * The Regents of the University of California. All rights reserved. 41573Srgrimes * 51573Srgrimes * This code is derived from software contributed to Berkeley by 61573Srgrimes * Sean Eric Fagan of Cygnus Support. 71573Srgrimes * 81573Srgrimes * Redistribution and use in source and binary forms, with or without 91573Srgrimes * modification, are permitted provided that the following conditions 101573Srgrimes * are met: 111573Srgrimes * 1. Redistributions of source code must retain the above copyright 121573Srgrimes * notice, this list of conditions and the following disclaimer. 131573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141573Srgrimes * notice, this list of conditions and the following disclaimer in the 151573Srgrimes * documentation and/or other materials provided with the distribution. 161573Srgrimes * 3. All advertising materials mentioning features or use of this software 171573Srgrimes * must display the following acknowledgement: 181573Srgrimes * This product includes software developed by the University of 191573Srgrimes * California, Berkeley and its contributors. 201573Srgrimes * 4. Neither the name of the University nor the names of its contributors 211573Srgrimes * may be used to endorse or promote products derived from this software 221573Srgrimes * without specific prior written permission. 231573Srgrimes * 241573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341573Srgrimes * SUCH DAMAGE. 351573Srgrimes */ 361573Srgrimes 371573Srgrimes#if defined(LIBC_SCCS) && !defined(lint) 381573Srgrimesstatic char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94"; 391573Srgrimes#endif /* LIBC_SCCS and not lint */ 401573Srgrimes 411573Srgrimes#include <sys/param.h> 421573Srgrimes#include <sys/sysctl.h> 431573Srgrimes#include <sys/resource.h> 441573Srgrimes 451573Srgrimes#include <errno.h> 466171Sbde#include <time.h> 471573Srgrimes#include <unistd.h> 481573Srgrimes 491573Srgrimes/* 501573Srgrimes * sysconf -- 511573Srgrimes * get configurable system variables. 521573Srgrimes * 531573Srgrimes * XXX 541573Srgrimes * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 551573Srgrimes * not change during the lifetime of the calling process. This would seem 561573Srgrimes * to require that any change to system limits kill all running processes. 571573Srgrimes * A workaround might be to cache the values when they are first retrieved 581573Srgrimes * and then simply return the cached value on subsequent calls. This is 591573Srgrimes * less useful than returning up-to-date values, however. 601573Srgrimes */ 611573Srgrimeslong 621573Srgrimessysconf(name) 631573Srgrimes int name; 641573Srgrimes{ 651573Srgrimes struct clockinfo clk; 661573Srgrimes struct rlimit rl; 671573Srgrimes size_t len; 681573Srgrimes int mib[2], value; 691573Srgrimes 701573Srgrimes len = sizeof(value); 711573Srgrimes 721573Srgrimes switch (name) { 731573Srgrimes/* 1003.1 */ 741573Srgrimes case _SC_ARG_MAX: 751573Srgrimes mib[0] = CTL_KERN; 761573Srgrimes mib[1] = KERN_ARGMAX; 771573Srgrimes break; 781573Srgrimes case _SC_CHILD_MAX: 791573Srgrimes return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur); 801573Srgrimes case _SC_CLK_TCK: 811573Srgrimes return (CLK_TCK); 821573Srgrimes case _SC_JOB_CONTROL: 831573Srgrimes mib[0] = CTL_KERN; 841573Srgrimes mib[1] = KERN_JOB_CONTROL; 851573Srgrimes goto yesno; 861573Srgrimes case _SC_NGROUPS_MAX: 871573Srgrimes mib[0] = CTL_KERN; 881573Srgrimes mib[1] = KERN_NGROUPS; 891573Srgrimes break; 901573Srgrimes case _SC_OPEN_MAX: 911573Srgrimes return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur); 921573Srgrimes case _SC_STREAM_MAX: 931573Srgrimes mib[0] = CTL_USER; 941573Srgrimes mib[1] = USER_STREAM_MAX; 951573Srgrimes break; 961573Srgrimes case _SC_TZNAME_MAX: 971573Srgrimes mib[0] = CTL_USER; 981573Srgrimes mib[1] = USER_TZNAME_MAX; 991573Srgrimes break; 1001573Srgrimes case _SC_SAVED_IDS: 1011573Srgrimes mib[0] = CTL_KERN; 1021573Srgrimes mib[1] = KERN_SAVED_IDS; 1031573Srgrimes goto yesno; 1041573Srgrimes case _SC_VERSION: 1051573Srgrimes mib[0] = CTL_KERN; 1061573Srgrimes mib[1] = KERN_POSIX1; 1071573Srgrimes break; 1081573Srgrimes 1091573Srgrimes/* 1003.2 */ 1101573Srgrimes case _SC_BC_BASE_MAX: 1111573Srgrimes mib[0] = CTL_USER; 1121573Srgrimes mib[1] = USER_BC_BASE_MAX; 1131573Srgrimes break; 1141573Srgrimes case _SC_BC_DIM_MAX: 1151573Srgrimes mib[0] = CTL_USER; 1161573Srgrimes mib[1] = USER_BC_DIM_MAX; 1171573Srgrimes break; 1181573Srgrimes case _SC_BC_SCALE_MAX: 1191573Srgrimes mib[0] = CTL_USER; 1201573Srgrimes mib[1] = USER_BC_SCALE_MAX; 1211573Srgrimes break; 1221573Srgrimes case _SC_BC_STRING_MAX: 1231573Srgrimes mib[0] = CTL_USER; 1241573Srgrimes mib[1] = USER_BC_STRING_MAX; 1251573Srgrimes break; 1261573Srgrimes case _SC_COLL_WEIGHTS_MAX: 1271573Srgrimes mib[0] = CTL_USER; 1281573Srgrimes mib[1] = USER_COLL_WEIGHTS_MAX; 1291573Srgrimes break; 1301573Srgrimes case _SC_EXPR_NEST_MAX: 1311573Srgrimes mib[0] = CTL_USER; 1321573Srgrimes mib[1] = USER_EXPR_NEST_MAX; 1331573Srgrimes break; 1341573Srgrimes case _SC_LINE_MAX: 1351573Srgrimes mib[0] = CTL_USER; 1361573Srgrimes mib[1] = USER_LINE_MAX; 1371573Srgrimes break; 1381573Srgrimes case _SC_RE_DUP_MAX: 1391573Srgrimes mib[0] = CTL_USER; 1401573Srgrimes mib[1] = USER_RE_DUP_MAX; 1411573Srgrimes break; 1421573Srgrimes case _SC_2_VERSION: 1431573Srgrimes mib[0] = CTL_USER; 1441573Srgrimes mib[1] = USER_POSIX2_VERSION; 1451573Srgrimes break; 1461573Srgrimes case _SC_2_C_BIND: 1471573Srgrimes mib[0] = CTL_USER; 1481573Srgrimes mib[1] = USER_POSIX2_C_BIND; 1491573Srgrimes goto yesno; 1501573Srgrimes case _SC_2_C_DEV: 1511573Srgrimes mib[0] = CTL_USER; 1521573Srgrimes mib[1] = USER_POSIX2_C_DEV; 1531573Srgrimes goto yesno; 1541573Srgrimes case _SC_2_CHAR_TERM: 1551573Srgrimes mib[0] = CTL_USER; 1561573Srgrimes mib[1] = USER_POSIX2_CHAR_TERM; 1571573Srgrimes goto yesno; 1581573Srgrimes case _SC_2_FORT_DEV: 1591573Srgrimes mib[0] = CTL_USER; 1601573Srgrimes mib[1] = USER_POSIX2_FORT_DEV; 1611573Srgrimes goto yesno; 1621573Srgrimes case _SC_2_FORT_RUN: 1631573Srgrimes mib[0] = CTL_USER; 1641573Srgrimes mib[1] = USER_POSIX2_FORT_RUN; 1651573Srgrimes goto yesno; 1661573Srgrimes case _SC_2_LOCALEDEF: 1671573Srgrimes mib[0] = CTL_USER; 1681573Srgrimes mib[1] = USER_POSIX2_LOCALEDEF; 1691573Srgrimes goto yesno; 1701573Srgrimes case _SC_2_SW_DEV: 1711573Srgrimes mib[0] = CTL_USER; 1721573Srgrimes mib[1] = USER_POSIX2_SW_DEV; 1731573Srgrimes goto yesno; 1741573Srgrimes case _SC_2_UPE: 1751573Srgrimes mib[0] = CTL_USER; 1761573Srgrimes mib[1] = USER_POSIX2_UPE; 1771573Srgrimesyesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) 1781573Srgrimes return (-1); 1791573Srgrimes if (value == 0) 1801573Srgrimes return (-1); 1811573Srgrimes return (value); 1821573Srgrimes break; 1831573Srgrimes default: 1841573Srgrimes errno = EINVAL; 1851573Srgrimes return (-1); 1861573Srgrimes } 1871573Srgrimes return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); 1881573Srgrimes} 189