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 #if defined(LIBC_RCS) && !defined(lint) 42 static const char rcsid[] = 43 "$FreeBSD$"; 44 #endif /* LIBC_RCS and not lint */ 45 46 #include <sys/_posix.h> 47 #include <sys/param.h> 48 #include <sys/time.h> 49 #include <sys/sysctl.h> 50 #include <sys/resource.h> 51 52 #include <errno.h> 53 #include <time.h> 54 #include <unistd.h> 55 56 /* 57 * sysconf -- 58 * get configurable system variables. 59 * 60 * XXX 61 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 62 * not change during the lifetime of the calling process. This would seem 63 * to require that any change to system limits kill all running processes. 64 * A workaround might be to cache the values when they are first retrieved 65 * and then simply return the cached value on subsequent calls. This is 66 * less useful than returning up-to-date values, however. 67 */ 68 long 69 sysconf(name) 70 int name; 71 { 72 struct rlimit rl; 73 size_t len; 74 int mib[2], value; 75 long defaultresult; 76 77 len = sizeof(value); 78 defaultresult = -1; 79 80 switch (name) { 81 /* 1003.1 */ 82 case _SC_ARG_MAX: 83 mib[0] = CTL_KERN; 84 mib[1] = KERN_ARGMAX; 85 break; 86 case _SC_CHILD_MAX: 87 return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur); 88 case _SC_CLK_TCK: 89 return (CLK_TCK); 90 case _SC_JOB_CONTROL: 91 mib[0] = CTL_KERN; 92 mib[1] = KERN_JOB_CONTROL; 93 goto yesno; 94 case _SC_NGROUPS_MAX: 95 mib[0] = CTL_KERN; 96 mib[1] = KERN_NGROUPS; 97 break; 98 case _SC_OPEN_MAX: 99 return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur); 100 case _SC_STREAM_MAX: 101 mib[0] = CTL_USER; 102 mib[1] = USER_STREAM_MAX; 103 break; 104 case _SC_TZNAME_MAX: 105 mib[0] = CTL_USER; 106 mib[1] = USER_TZNAME_MAX; 107 break; 108 case _SC_SAVED_IDS: 109 mib[0] = CTL_KERN; 110 mib[1] = KERN_SAVED_IDS; 111 goto yesno; 112 case _SC_VERSION: 113 mib[0] = CTL_KERN; 114 mib[1] = KERN_POSIX1; 115 break; 116 117 /* 1003.2 */ 118 case _SC_BC_BASE_MAX: 119 mib[0] = CTL_USER; 120 mib[1] = USER_BC_BASE_MAX; 121 break; 122 case _SC_BC_DIM_MAX: 123 mib[0] = CTL_USER; 124 mib[1] = USER_BC_DIM_MAX; 125 break; 126 case _SC_BC_SCALE_MAX: 127 mib[0] = CTL_USER; 128 mib[1] = USER_BC_SCALE_MAX; 129 break; 130 case _SC_BC_STRING_MAX: 131 mib[0] = CTL_USER; 132 mib[1] = USER_BC_STRING_MAX; 133 break; 134 case _SC_COLL_WEIGHTS_MAX: 135 mib[0] = CTL_USER; 136 mib[1] = USER_COLL_WEIGHTS_MAX; 137 break; 138 case _SC_EXPR_NEST_MAX: 139 mib[0] = CTL_USER; 140 mib[1] = USER_EXPR_NEST_MAX; 141 break; 142 case _SC_LINE_MAX: 143 mib[0] = CTL_USER; 144 mib[1] = USER_LINE_MAX; 145 break; 146 case _SC_RE_DUP_MAX: 147 mib[0] = CTL_USER; 148 mib[1] = USER_RE_DUP_MAX; 149 break; 150 case _SC_2_VERSION: 151 mib[0] = CTL_USER; 152 mib[1] = USER_POSIX2_VERSION; 153 break; 154 case _SC_2_C_BIND: 155 mib[0] = CTL_USER; 156 mib[1] = USER_POSIX2_C_BIND; 157 goto yesno; 158 case _SC_2_C_DEV: 159 mib[0] = CTL_USER; 160 mib[1] = USER_POSIX2_C_DEV; 161 goto yesno; 162 case _SC_2_CHAR_TERM: 163 mib[0] = CTL_USER; 164 mib[1] = USER_POSIX2_CHAR_TERM; 165 goto yesno; 166 case _SC_2_FORT_DEV: 167 mib[0] = CTL_USER; 168 mib[1] = USER_POSIX2_FORT_DEV; 169 goto yesno; 170 case _SC_2_FORT_RUN: 171 mib[0] = CTL_USER; 172 mib[1] = USER_POSIX2_FORT_RUN; 173 goto yesno; 174 case _SC_2_LOCALEDEF: 175 mib[0] = CTL_USER; 176 mib[1] = USER_POSIX2_LOCALEDEF; 177 goto yesno; 178 case _SC_2_SW_DEV: 179 mib[0] = CTL_USER; 180 mib[1] = USER_POSIX2_SW_DEV; 181 goto yesno; 182 case _SC_2_UPE: 183 mib[0] = CTL_USER; 184 mib[1] = USER_POSIX2_UPE; 185 goto yesno; 186 187 #ifdef _P1003_1B_VISIBLE 188 /* POSIX.1B */ 189 190 case _SC_ASYNCHRONOUS_IO: 191 mib[0] = CTL_P1003_1B; 192 mib[1] = CTL_P1003_1B_ASYNCHRONOUS_IO; 193 goto yesno; 194 case _SC_MAPPED_FILES: 195 mib[0] = CTL_P1003_1B; 196 mib[1] = CTL_P1003_1B_MAPPED_FILES; 197 goto yesno; 198 case _SC_MEMLOCK: 199 mib[0] = CTL_P1003_1B; 200 mib[1] = CTL_P1003_1B_MEMLOCK; 201 goto yesno; 202 case _SC_MEMLOCK_RANGE: 203 mib[0] = CTL_P1003_1B; 204 mib[1] = CTL_P1003_1B_MEMLOCK_RANGE; 205 goto yesno; 206 case _SC_MEMORY_PROTECTION: 207 mib[0] = CTL_P1003_1B; 208 mib[1] = CTL_P1003_1B_MEMORY_PROTECTION; 209 goto yesno; 210 case _SC_MESSAGE_PASSING: 211 mib[0] = CTL_P1003_1B; 212 mib[1] = CTL_P1003_1B_MESSAGE_PASSING; 213 goto yesno; 214 case _SC_PRIORITIZED_IO: 215 mib[0] = CTL_P1003_1B; 216 mib[1] = CTL_P1003_1B_PRIORITIZED_IO; 217 goto yesno; 218 case _SC_PRIORITY_SCHEDULING: 219 mib[0] = CTL_P1003_1B; 220 mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING; 221 goto yesno; 222 case _SC_REALTIME_SIGNALS: 223 mib[0] = CTL_P1003_1B; 224 mib[1] = CTL_P1003_1B_REALTIME_SIGNALS; 225 goto yesno; 226 case _SC_SEMAPHORES: 227 mib[0] = CTL_P1003_1B; 228 mib[1] = CTL_P1003_1B_SEMAPHORES; 229 goto yesno; 230 case _SC_FSYNC: 231 mib[0] = CTL_P1003_1B; 232 mib[1] = CTL_P1003_1B_FSYNC; 233 goto yesno; 234 case _SC_SHARED_MEMORY_OBJECTS: 235 mib[0] = CTL_P1003_1B; 236 mib[1] = CTL_P1003_1B_SHARED_MEMORY_OBJECTS; 237 goto yesno; 238 case _SC_SYNCHRONIZED_IO: 239 mib[0] = CTL_P1003_1B; 240 mib[1] = CTL_P1003_1B_SYNCHRONIZED_IO; 241 goto yesno; 242 case _SC_TIMERS: 243 mib[0] = CTL_P1003_1B; 244 mib[1] = CTL_P1003_1B_TIMERS; 245 goto yesno; 246 case _SC_AIO_LISTIO_MAX: 247 mib[0] = CTL_P1003_1B; 248 mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX; 249 goto yesno; 250 case _SC_AIO_MAX: 251 mib[0] = CTL_P1003_1B; 252 mib[1] = CTL_P1003_1B_AIO_MAX; 253 goto yesno; 254 case _SC_AIO_PRIO_DELTA_MAX: 255 mib[0] = CTL_P1003_1B; 256 mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX; 257 goto yesno; 258 case _SC_DELAYTIMER_MAX: 259 mib[0] = CTL_P1003_1B; 260 mib[1] = CTL_P1003_1B_DELAYTIMER_MAX; 261 goto yesno; 262 case _SC_MQ_OPEN_MAX: 263 mib[0] = CTL_P1003_1B; 264 mib[1] = CTL_P1003_1B_MQ_OPEN_MAX; 265 goto yesno; 266 case _SC_PAGESIZE: 267 defaultresult = getpagesize(); 268 mib[0] = CTL_P1003_1B; 269 mib[1] = CTL_P1003_1B_PAGESIZE; 270 goto yesno; 271 case _SC_RTSIG_MAX: 272 mib[0] = CTL_P1003_1B; 273 mib[1] = CTL_P1003_1B_RTSIG_MAX; 274 goto yesno; 275 case _SC_SEM_NSEMS_MAX: 276 mib[0] = CTL_P1003_1B; 277 mib[1] = CTL_P1003_1B_SEM_NSEMS_MAX; 278 goto yesno; 279 case _SC_SEM_VALUE_MAX: 280 mib[0] = CTL_P1003_1B; 281 mib[1] = CTL_P1003_1B_SEM_VALUE_MAX; 282 goto yesno; 283 case _SC_SIGQUEUE_MAX: 284 mib[0] = CTL_P1003_1B; 285 mib[1] = CTL_P1003_1B_SIGQUEUE_MAX; 286 goto yesno; 287 case _SC_TIMER_MAX: 288 mib[0] = CTL_P1003_1B; 289 mib[1] = CTL_P1003_1B_TIMER_MAX; 290 goto yesno; 291 #endif /* _P1003_1B_VISIBLE */ 292 293 #ifdef _SC_IOV_MAX 294 case _SC_IOV_MAX: 295 mib[0] = CTL_KERN; 296 mib[1] = KERN_IOV_MAX; 297 break; 298 #endif 299 300 yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) 301 return (-1); 302 if (value == 0) 303 return (defaultresult); 304 return (value); 305 break; 306 default: 307 errno = EINVAL; 308 return (-1); 309 } 310 return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); 311 } 312