/* $NetBSD: sysconf.c,v 1.22 2006/11/25 21:40:04 christos Exp $ */ /*- * Copyright (c) 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Sean Eric Fagan of Cygnus Support. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #if defined(LIBC_SCCS) && !defined(lint) #if 0 static char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94"; #else __RCSID("$NetBSD: sysconf.c,v 1.22 2006/11/25 21:40:04 christos Exp $"); #endif #endif /* LIBC_SCCS and not lint */ #include "namespace.h" #include #include #include #include #include #include #include #include #ifdef __weak_alias __weak_alias(sysconf,__sysconf) #endif /* * sysconf -- * get configurable system variables. * * XXX * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values * not change during the lifetime of the calling process. This would seem * to require that any change to system limits kill all running processes. * A workaround might be to cache the values when they are first retrieved * and then simply return the cached value on subsequent calls. This is * less useful than returning up-to-date values, however. */ long sysconf(name) int name; { struct rlimit rl; size_t len; int mib[3], value; struct clockinfo tmpclock; static int clk_tck; len = sizeof(value); switch (name) { /* 1003.1 */ case _SC_ARG_MAX: mib[0] = CTL_KERN; mib[1] = KERN_ARGMAX; break; case _SC_CHILD_MAX: return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : (long)rl.rlim_cur); case _O_SC_CLK_TCK: /* * For applications compiled when CLK_TCK was a compile-time * constant. */ return 100; case _SC_CLK_TCK: /* * Has to be handled specially because it returns a * struct clockinfo instead of an integer. Also, since * this might be called often by some things that * don't grok CLK_TCK can be a macro expanding to a * function, cache the value. */ if (clk_tck == 0) { mib[0] = CTL_KERN; mib[1] = KERN_CLOCKRATE; len = sizeof(struct clockinfo); clk_tck = sysctl(mib, 2, &tmpclock, &len, NULL, 0) == -1 ? -1 : tmpclock.hz; } return(clk_tck); case _SC_JOB_CONTROL: mib[0] = CTL_KERN; mib[1] = KERN_JOB_CONTROL; goto yesno; case _SC_NGROUPS_MAX: mib[0] = CTL_KERN; mib[1] = KERN_NGROUPS; break; case _SC_OPEN_MAX: return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : (long)rl.rlim_cur); case _SC_STREAM_MAX: mib[0] = CTL_USER; mib[1] = USER_STREAM_MAX; break; case _SC_TZNAME_MAX: mib[0] = CTL_USER; mib[1] = USER_TZNAME_MAX; break; case _SC_SAVED_IDS: mib[0] = CTL_KERN; mib[1] = KERN_SAVED_IDS; goto yesno; case _SC_VERSION: mib[0] = CTL_KERN; mib[1] = KERN_POSIX1; break; /* 1003.1b */ case _SC_PAGESIZE: mib[0] = CTL_HW; mib[1] = HW_PAGESIZE; break; case _SC_FSYNC: mib[0] = CTL_KERN; mib[1] = KERN_FSYNC; goto yesno; case _SC_SYNCHRONIZED_IO: mib[0] = CTL_KERN; mib[1] = KERN_SYNCHRONIZED_IO; goto yesno; case _SC_MAPPED_FILES: mib[0] = CTL_KERN; mib[1] = KERN_MAPPED_FILES; goto yesno; case _SC_MEMLOCK: mib[0] = CTL_KERN; mib[1] = KERN_MEMLOCK; goto yesno; case _SC_MEMLOCK_RANGE: mib[0] = CTL_KERN; mib[1] = KERN_MEMLOCK_RANGE; goto yesno; case _SC_MEMORY_PROTECTION: mib[0] = CTL_KERN; mib[1] = KERN_MEMORY_PROTECTION; goto yesno; case _SC_MONOTONIC_CLOCK: mib[0] = CTL_KERN; mib[1] = KERN_MONOTONIC_CLOCK; goto yesno; case _SC_SEMAPHORES: mib[0] = CTL_KERN; mib[1] = KERN_POSIX_SEMAPHORES; goto yesno; case _SC_TIMERS: mib[0] = CTL_KERN; mib[1] = KERN_POSIX_TIMERS; goto yesno; /* 1003.1c */ case _SC_LOGIN_NAME_MAX: mib[0] = CTL_KERN; mib[1] = KERN_LOGIN_NAME_MAX; break; case _SC_THREADS: mib[0] = CTL_KERN; mib[1] = KERN_POSIX_THREADS; goto yesno; /* 1003.1j */ case _SC_BARRIERS: mib[0] = CTL_KERN; mib[1] = KERN_POSIX_BARRIERS; goto yesno; case _SC_SPIN_LOCKS: mib[0] = CTL_KERN; mib[1] = KERN_POSIX_SPIN_LOCKS; goto yesno; /* Historical; Threads option in 1003.1-2001 */ case _SC_READER_WRITER_LOCKS: mib[0] = CTL_KERN; mib[1] = KERN_POSIX_READER_WRITER_LOCKS; goto yesno; /* 1003.2 */ case _SC_BC_BASE_MAX: mib[0] = CTL_USER; mib[1] = USER_BC_BASE_MAX; break; case _SC_BC_DIM_MAX: mib[0] = CTL_USER; mib[1] = USER_BC_DIM_MAX; break; case _SC_BC_SCALE_MAX: mib[0] = CTL_USER; mib[1] = USER_BC_SCALE_MAX; break; case _SC_BC_STRING_MAX: mib[0] = CTL_USER; mib[1] = USER_BC_STRING_MAX; break; case _SC_COLL_WEIGHTS_MAX: mib[0] = CTL_USER; mib[1] = USER_COLL_WEIGHTS_MAX; break; case _SC_EXPR_NEST_MAX: mib[0] = CTL_USER; mib[1] = USER_EXPR_NEST_MAX; break; case _SC_LINE_MAX: mib[0] = CTL_USER; mib[1] = USER_LINE_MAX; break; case _SC_RE_DUP_MAX: mib[0] = CTL_USER; mib[1] = USER_RE_DUP_MAX; break; case _SC_2_VERSION: mib[0] = CTL_USER; mib[1] = USER_POSIX2_VERSION; break; case _SC_2_C_BIND: mib[0] = CTL_USER; mib[1] = USER_POSIX2_C_BIND; goto yesno; case _SC_2_C_DEV: mib[0] = CTL_USER; mib[1] = USER_POSIX2_C_DEV; goto yesno; case _SC_2_CHAR_TERM: mib[0] = CTL_USER; mib[1] = USER_POSIX2_CHAR_TERM; goto yesno; case _SC_2_FORT_DEV: mib[0] = CTL_USER; mib[1] = USER_POSIX2_FORT_DEV; goto yesno; case _SC_2_FORT_RUN: mib[0] = CTL_USER; mib[1] = USER_POSIX2_FORT_RUN; goto yesno; case _SC_2_LOCALEDEF: mib[0] = CTL_USER; mib[1] = USER_POSIX2_LOCALEDEF; goto yesno; case _SC_2_SW_DEV: mib[0] = CTL_USER; mib[1] = USER_POSIX2_SW_DEV; goto yesno; case _SC_2_UPE: mib[0] = CTL_USER; mib[1] = USER_POSIX2_UPE; goto yesno; /* XPG 4.2 */ case _SC_IOV_MAX: mib[0] = CTL_KERN; mib[1] = KERN_IOV_MAX; break; case _SC_XOPEN_SHM: mib[0] = CTL_KERN; mib[1] = KERN_SYSVIPC; mib[2] = KERN_SYSVIPC_SHM; if (sysctl(mib, 3, &value, &len, NULL, 0) == -1) return (-1); if (value == 0) return (-1); return (0); /* 1003.1-2001, XSI Option Group */ case _SC_ATEXIT_MAX: mib[0] = CTL_USER; mib[1] = USER_ATEXIT_MAX; break; /* 1003.1-2001, TSF */ case _SC_GETGR_R_SIZE_MAX: return _GETGR_R_SIZE_MAX; case _SC_GETPW_R_SIZE_MAX: return _GETPW_R_SIZE_MAX; yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) return (-1); if (value == 0) return (-1); return (value); /*NOTREACHED*/ break; default: errno = EINVAL; return (-1); } return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); }