1 /*- 2 * Copyright (c) 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Sean Eric Fagan of Cygnus Support. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #if defined(LIBC_SCCS) && !defined(lint) 38 static char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94"; 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include <sys/_posix.h> 42 #include <sys/param.h> 43 #include <sys/time.h> 44 #include <sys/sysctl.h> 45 #include <sys/resource.h> 46 47 #include <errno.h> 48 #include <time.h> 49 #include <unistd.h> 50 51 /* 52 * sysconf -- 53 * get configurable system variables. 54 * 55 * XXX 56 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 57 * not change during the lifetime of the calling process. This would seem 58 * to require that any change to system limits kill all running processes. 59 * A workaround might be to cache the values when they are first retrieved 60 * and then simply return the cached value on subsequent calls. This is 61 * less useful than returning up-to-date values, however. 62 */ 63 long 64 sysconf(name) 65 int name; 66 { 67 struct rlimit rl; 68 size_t len; 69 int mib[2], value; 70 long defaultresult; 71 72 len = sizeof(value); 73 defaultresult = -1; 74 75 switch (name) { 76 /* 1003.1 */ 77 case _SC_ARG_MAX: 78 mib[0] = CTL_KERN; 79 mib[1] = KERN_ARGMAX; 80 break; 81 case _SC_CHILD_MAX: 82 return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur); 83 case _SC_CLK_TCK: 84 return (CLK_TCK); 85 case _SC_JOB_CONTROL: 86 mib[0] = CTL_KERN; 87 mib[1] = KERN_JOB_CONTROL; 88 goto yesno; 89 case _SC_NGROUPS_MAX: 90 mib[0] = CTL_KERN; 91 mib[1] = KERN_NGROUPS; 92 break; 93 case _SC_OPEN_MAX: 94 return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur); 95 case _SC_STREAM_MAX: 96 mib[0] = CTL_USER; 97 mib[1] = USER_STREAM_MAX; 98 break; 99 case _SC_TZNAME_MAX: 100 mib[0] = CTL_USER; 101 mib[1] = USER_TZNAME_MAX; 102 break; 103 case _SC_SAVED_IDS: 104 mib[0] = CTL_KERN; 105 mib[1] = KERN_SAVED_IDS; 106 goto yesno; 107 case _SC_VERSION: 108 mib[0] = CTL_KERN; 109 mib[1] = KERN_POSIX1; 110 break; 111 112 /* 1003.2 */ 113 case _SC_BC_BASE_MAX: 114 mib[0] = CTL_USER; 115 mib[1] = USER_BC_BASE_MAX; 116 break; 117 case _SC_BC_DIM_MAX: 118 mib[0] = CTL_USER; 119 mib[1] = USER_BC_DIM_MAX; 120 break; 121 case _SC_BC_SCALE_MAX: 122 mib[0] = CTL_USER; 123 mib[1] = USER_BC_SCALE_MAX; 124 break; 125 case _SC_BC_STRING_MAX: 126 mib[0] = CTL_USER; 127 mib[1] = USER_BC_STRING_MAX; 128 break; 129 case _SC_COLL_WEIGHTS_MAX: 130 mib[0] = CTL_USER; 131 mib[1] = USER_COLL_WEIGHTS_MAX; 132 break; 133 case _SC_EXPR_NEST_MAX: 134 mib[0] = CTL_USER; 135 mib[1] = USER_EXPR_NEST_MAX; 136 break; 137 case _SC_LINE_MAX: 138 mib[0] = CTL_USER; 139 mib[1] = USER_LINE_MAX; 140 break; 141 case _SC_RE_DUP_MAX: 142 mib[0] = CTL_USER; 143 mib[1] = USER_RE_DUP_MAX; 144 break; 145 case _SC_2_VERSION: 146 mib[0] = CTL_USER; 147 mib[1] = USER_POSIX2_VERSION; 148 break; 149 case _SC_2_C_BIND: 150 mib[0] = CTL_USER; 151 mib[1] = USER_POSIX2_C_BIND; 152 goto yesno; 153 case _SC_2_C_DEV: 154 mib[0] = CTL_USER; 155 mib[1] = USER_POSIX2_C_DEV; 156 goto yesno; 157 case _SC_2_CHAR_TERM: 158 mib[0] = CTL_USER; 159 mib[1] = USER_POSIX2_CHAR_TERM; 160 goto yesno; 161 case _SC_2_FORT_DEV: 162 mib[0] = CTL_USER; 163 mib[1] = USER_POSIX2_FORT_DEV; 164 goto yesno; 165 case _SC_2_FORT_RUN: 166 mib[0] = CTL_USER; 167 mib[1] = USER_POSIX2_FORT_RUN; 168 goto yesno; 169 case _SC_2_LOCALEDEF: 170 mib[0] = CTL_USER; 171 mib[1] = USER_POSIX2_LOCALEDEF; 172 goto yesno; 173 case _SC_2_SW_DEV: 174 mib[0] = CTL_USER; 175 mib[1] = USER_POSIX2_SW_DEV; 176 goto yesno; 177 case _SC_2_UPE: 178 mib[0] = CTL_USER; 179 mib[1] = USER_POSIX2_UPE; 180 goto yesno; 181 182 #ifdef _P1003_1B_VISIBLE 183 /* POSIX.1B */ 184 185 case _SC_ASYNCHRONOUS_IO: 186 mib[0] = CTL_P1003_1B; 187 mib[1] = CTL_P1003_1B_ASYNCHRONOUS_IO; 188 goto yesno; 189 case _SC_MAPPED_FILES: 190 mib[0] = CTL_P1003_1B; 191 mib[1] = CTL_P1003_1B_MAPPED_FILES; 192 goto yesno; 193 case _SC_MEMLOCK: 194 mib[0] = CTL_P1003_1B; 195 mib[1] = CTL_P1003_1B_MEMLOCK; 196 goto yesno; 197 case _SC_MEMLOCK_RANGE: 198 mib[0] = CTL_P1003_1B; 199 mib[1] = CTL_P1003_1B_MEMLOCK_RANGE; 200 goto yesno; 201 case _SC_MEMORY_PROTECTION: 202 mib[0] = CTL_P1003_1B; 203 mib[1] = CTL_P1003_1B_MEMORY_PROTECTION; 204 goto yesno; 205 case _SC_MESSAGE_PASSING: 206 mib[0] = CTL_P1003_1B; 207 mib[1] = CTL_P1003_1B_MESSAGE_PASSING; 208 goto yesno; 209 case _SC_PRIORITIZED_IO: 210 mib[0] = CTL_P1003_1B; 211 mib[1] = CTL_P1003_1B_PRIORITIZED_IO; 212 goto yesno; 213 case _SC_PRIORITY_SCHEDULING: 214 mib[0] = CTL_P1003_1B; 215 mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING; 216 goto yesno; 217 case _SC_REALTIME_SIGNALS: 218 mib[0] = CTL_P1003_1B; 219 mib[1] = CTL_P1003_1B_REALTIME_SIGNALS; 220 goto yesno; 221 case _SC_SEMAPHORES: 222 mib[0] = CTL_P1003_1B; 223 mib[1] = CTL_P1003_1B_SEMAPHORES; 224 goto yesno; 225 case _SC_FSYNC: 226 mib[0] = CTL_P1003_1B; 227 mib[1] = CTL_P1003_1B_FSYNC; 228 goto yesno; 229 case _SC_SHARED_MEMORY_OBJECTS: 230 mib[0] = CTL_P1003_1B; 231 mib[1] = CTL_P1003_1B_SHARED_MEMORY_OBJECTS; 232 goto yesno; 233 case _SC_SYNCHRONIZED_IO: 234 mib[0] = CTL_P1003_1B; 235 mib[1] = CTL_P1003_1B_SYNCHRONIZED_IO; 236 goto yesno; 237 case _SC_TIMERS: 238 mib[0] = CTL_P1003_1B; 239 mib[1] = CTL_P1003_1B_TIMERS; 240 goto yesno; 241 case _SC_AIO_LISTIO_MAX: 242 mib[0] = CTL_P1003_1B; 243 mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX; 244 goto yesno; 245 case _SC_AIO_MAX: 246 mib[0] = CTL_P1003_1B; 247 mib[1] = CTL_P1003_1B_AIO_MAX; 248 goto yesno; 249 case _SC_AIO_PRIO_DELTA_MAX: 250 mib[0] = CTL_P1003_1B; 251 mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX; 252 goto yesno; 253 case _SC_DELAYTIMER_MAX: 254 mib[0] = CTL_P1003_1B; 255 mib[1] = CTL_P1003_1B_DELAYTIMER_MAX; 256 goto yesno; 257 case _SC_MQ_OPEN_MAX: 258 mib[0] = CTL_P1003_1B; 259 mib[1] = CTL_P1003_1B_MQ_OPEN_MAX; 260 goto yesno; 261 case _SC_PAGESIZE: 262 defaultresult = getpagesize(); 263 mib[0] = CTL_P1003_1B; 264 mib[1] = CTL_P1003_1B_PAGESIZE; 265 goto yesno; 266 case _SC_RTSIG_MAX: 267 mib[0] = CTL_P1003_1B; 268 mib[1] = CTL_P1003_1B_RTSIG_MAX; 269 goto yesno; 270 case _SC_SEM_NSEMS_MAX: 271 mib[0] = CTL_P1003_1B; 272 mib[1] = CTL_P1003_1B_SEM_NSEMS_MAX; 273 goto yesno; 274 case _SC_SEM_VALUE_MAX: 275 mib[0] = CTL_P1003_1B; 276 mib[1] = CTL_P1003_1B_SEM_VALUE_MAX; 277 goto yesno; 278 case _SC_SIGQUEUE_MAX: 279 mib[0] = CTL_P1003_1B; 280 mib[1] = CTL_P1003_1B_SIGQUEUE_MAX; 281 goto yesno; 282 case _SC_TIMER_MAX: 283 mib[0] = CTL_P1003_1B; 284 mib[1] = CTL_P1003_1B_TIMER_MAX; 285 goto yesno; 286 #endif /* _P1003_1B_VISIBLE */ 287 288 yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) 289 return (-1); 290 if (value == 0) 291 return (defaultresult); 292 return (value); 293 break; 294 default: 295 errno = EINVAL; 296 return (-1); 297 } 298 return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); 299 } 300