/* $OpenBSD: sysconf.c,v 1.10 2008/06/25 14:54:44 millert 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 #include #include #include #include #include #include #include #include /* * 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(int name) { struct rlimit rl; size_t len; int mib[3], value, namelen; len = sizeof(value); namelen = 2; 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 : rl.rlim_cur); case _SC_CLK_TCK: 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 : 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; /* 1003.1c */ case _SC_LOGIN_NAME_MAX: return (LOGIN_NAME_MAX); case _SC_THREAD_SAFE_FUNCTIONS: return (_POSIX_THREAD_SAFE_FUNCTIONS); case _SC_GETGR_R_SIZE_MAX: return (_PW_BUF_LEN); case _SC_GETPW_R_SIZE_MAX: return (_PW_BUF_LEN); /* 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_XOPEN_SHM: mib[0] = CTL_KERN; mib[1] = KERN_SYSVSHM; yesno: if (sysctl(mib, namelen, &value, &len, NULL, 0) == -1) return (-1); if (value == 0) return (-1); return (value); break; case _SC_SEM_NSEMS_MAX: case _SC_SEM_VALUE_MAX: mib[0] = CTL_KERN; mib[1] = KERN_SEMINFO; mib[2] = name = _SC_SEM_NSEMS_MAX ? KERN_SEMINFO_SEMMNS : KERN_SEMINFO_SEMVMX; namelen = 3; break; /* Extensions */ case _SC_PHYS_PAGES: { int64_t physmem; mib[0] = CTL_HW; mib[1] = HW_PHYSMEM64; len = sizeof(physmem); if (sysctl(mib, namelen, &physmem, &len, NULL, 0) == -1) return (-1); return (physmem / getpagesize()); } case _SC_AVPHYS_PAGES: { struct vmtotal vmtotal; mib[0] = CTL_VM; mib[1] = VM_METER; len = sizeof(vmtotal); if (sysctl(mib, namelen, &vmtotal, &len, NULL, 0) == -1) return (-1); return (vmtotal.t_free); } default: errno = EINVAL; return (-1); } return (sysctl(mib, namelen, &value, &len, NULL, 0) == -1 ? -1 : value); }