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 * @(#)sysconf.c 8.2 (Berkeley) 3/20/94 37 * $DragonFly: src/lib/libc/gen/sysconf.c,v 1.3 2004/11/09 17:52:45 joerg Exp $ 38 */ 39 40 #include <sys/_posix.h> 41 #include <sys/param.h> 42 #include <sys/time.h> 43 #include <sys/sysctl.h> 44 #include <sys/resource.h> 45 46 #include <errno.h> 47 #include <time.h> 48 #include <unistd.h> 49 50 /* 51 * sysconf -- 52 * get configurable system variables. 53 * 54 * XXX 55 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 56 * not change during the lifetime of the calling process. This would seem 57 * to require that any change to system limits kill all running processes. 58 * A workaround might be to cache the values when they are first retrieved 59 * and then simply return the cached value on subsequent calls. This is 60 * less useful than returning up-to-date values, however. 61 */ 62 long 63 sysconf(name) 64 int name; 65 { 66 struct rlimit rl; 67 size_t len; 68 int mib[2], value; 69 long defaultresult; 70 71 len = sizeof(value); 72 defaultresult = -1; 73 74 switch (name) { 75 /* 1003.1 */ 76 case _SC_ARG_MAX: 77 mib[0] = CTL_KERN; 78 mib[1] = KERN_ARGMAX; 79 break; 80 case _SC_CHILD_MAX: 81 return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur); 82 case _SC_CLK_TCK: 83 return (CLK_TCK); 84 case _SC_JOB_CONTROL: 85 mib[0] = CTL_KERN; 86 mib[1] = KERN_JOB_CONTROL; 87 goto yesno; 88 case _SC_NGROUPS_MAX: 89 mib[0] = CTL_KERN; 90 mib[1] = KERN_NGROUPS; 91 break; 92 case _SC_OPEN_MAX: 93 return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur); 94 case _SC_STREAM_MAX: 95 mib[0] = CTL_USER; 96 mib[1] = USER_STREAM_MAX; 97 break; 98 case _SC_TZNAME_MAX: 99 mib[0] = CTL_USER; 100 mib[1] = USER_TZNAME_MAX; 101 break; 102 case _SC_SAVED_IDS: 103 mib[0] = CTL_KERN; 104 mib[1] = KERN_SAVED_IDS; 105 goto yesno; 106 case _SC_VERSION: 107 mib[0] = CTL_KERN; 108 mib[1] = KERN_POSIX1; 109 break; 110 case _SC_IOV_MAX: 111 mib[0] = CTL_KERN; 112 mib[1] = KERN_IOV_MAX; 113 break; 114 115 /* 1003.2 */ 116 case _SC_BC_BASE_MAX: 117 mib[0] = CTL_USER; 118 mib[1] = USER_BC_BASE_MAX; 119 break; 120 case _SC_BC_DIM_MAX: 121 mib[0] = CTL_USER; 122 mib[1] = USER_BC_DIM_MAX; 123 break; 124 case _SC_BC_SCALE_MAX: 125 mib[0] = CTL_USER; 126 mib[1] = USER_BC_SCALE_MAX; 127 break; 128 case _SC_BC_STRING_MAX: 129 mib[0] = CTL_USER; 130 mib[1] = USER_BC_STRING_MAX; 131 break; 132 case _SC_COLL_WEIGHTS_MAX: 133 mib[0] = CTL_USER; 134 mib[1] = USER_COLL_WEIGHTS_MAX; 135 break; 136 case _SC_EXPR_NEST_MAX: 137 mib[0] = CTL_USER; 138 mib[1] = USER_EXPR_NEST_MAX; 139 break; 140 case _SC_LINE_MAX: 141 mib[0] = CTL_USER; 142 mib[1] = USER_LINE_MAX; 143 break; 144 case _SC_RE_DUP_MAX: 145 mib[0] = CTL_USER; 146 mib[1] = USER_RE_DUP_MAX; 147 break; 148 case _SC_2_VERSION: 149 mib[0] = CTL_USER; 150 mib[1] = USER_POSIX2_VERSION; 151 break; 152 case _SC_2_C_BIND: 153 mib[0] = CTL_USER; 154 mib[1] = USER_POSIX2_C_BIND; 155 goto yesno; 156 case _SC_2_C_DEV: 157 mib[0] = CTL_USER; 158 mib[1] = USER_POSIX2_C_DEV; 159 goto yesno; 160 case _SC_2_CHAR_TERM: 161 mib[0] = CTL_USER; 162 mib[1] = USER_POSIX2_CHAR_TERM; 163 goto yesno; 164 case _SC_2_FORT_DEV: 165 mib[0] = CTL_USER; 166 mib[1] = USER_POSIX2_FORT_DEV; 167 goto yesno; 168 case _SC_2_FORT_RUN: 169 mib[0] = CTL_USER; 170 mib[1] = USER_POSIX2_FORT_RUN; 171 goto yesno; 172 case _SC_2_LOCALEDEF: 173 mib[0] = CTL_USER; 174 mib[1] = USER_POSIX2_LOCALEDEF; 175 goto yesno; 176 case _SC_2_SW_DEV: 177 mib[0] = CTL_USER; 178 mib[1] = USER_POSIX2_SW_DEV; 179 goto yesno; 180 case _SC_2_UPE: 181 mib[0] = CTL_USER; 182 mib[1] = USER_POSIX2_UPE; 183 goto yesno; 184 185 #ifdef _P1003_1B_VISIBLE 186 /* POSIX.1B */ 187 188 case _SC_ASYNCHRONOUS_IO: 189 mib[0] = CTL_P1003_1B; 190 mib[1] = CTL_P1003_1B_ASYNCHRONOUS_IO; 191 goto yesno; 192 case _SC_MAPPED_FILES: 193 mib[0] = CTL_P1003_1B; 194 mib[1] = CTL_P1003_1B_MAPPED_FILES; 195 goto yesno; 196 case _SC_MEMLOCK: 197 mib[0] = CTL_P1003_1B; 198 mib[1] = CTL_P1003_1B_MEMLOCK; 199 goto yesno; 200 case _SC_MEMLOCK_RANGE: 201 mib[0] = CTL_P1003_1B; 202 mib[1] = CTL_P1003_1B_MEMLOCK_RANGE; 203 goto yesno; 204 case _SC_MEMORY_PROTECTION: 205 mib[0] = CTL_P1003_1B; 206 mib[1] = CTL_P1003_1B_MEMORY_PROTECTION; 207 goto yesno; 208 case _SC_MESSAGE_PASSING: 209 mib[0] = CTL_P1003_1B; 210 mib[1] = CTL_P1003_1B_MESSAGE_PASSING; 211 goto yesno; 212 case _SC_PRIORITIZED_IO: 213 mib[0] = CTL_P1003_1B; 214 mib[1] = CTL_P1003_1B_PRIORITIZED_IO; 215 goto yesno; 216 case _SC_PRIORITY_SCHEDULING: 217 mib[0] = CTL_P1003_1B; 218 mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING; 219 goto yesno; 220 case _SC_REALTIME_SIGNALS: 221 mib[0] = CTL_P1003_1B; 222 mib[1] = CTL_P1003_1B_REALTIME_SIGNALS; 223 goto yesno; 224 case _SC_SEMAPHORES: 225 mib[0] = CTL_P1003_1B; 226 mib[1] = CTL_P1003_1B_SEMAPHORES; 227 goto yesno; 228 case _SC_FSYNC: 229 mib[0] = CTL_P1003_1B; 230 mib[1] = CTL_P1003_1B_FSYNC; 231 goto yesno; 232 case _SC_SHARED_MEMORY_OBJECTS: 233 mib[0] = CTL_P1003_1B; 234 mib[1] = CTL_P1003_1B_SHARED_MEMORY_OBJECTS; 235 goto yesno; 236 case _SC_SYNCHRONIZED_IO: 237 mib[0] = CTL_P1003_1B; 238 mib[1] = CTL_P1003_1B_SYNCHRONIZED_IO; 239 goto yesno; 240 case _SC_TIMERS: 241 mib[0] = CTL_P1003_1B; 242 mib[1] = CTL_P1003_1B_TIMERS; 243 goto yesno; 244 case _SC_AIO_LISTIO_MAX: 245 mib[0] = CTL_P1003_1B; 246 mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX; 247 goto yesno; 248 case _SC_AIO_MAX: 249 mib[0] = CTL_P1003_1B; 250 mib[1] = CTL_P1003_1B_AIO_MAX; 251 goto yesno; 252 case _SC_AIO_PRIO_DELTA_MAX: 253 mib[0] = CTL_P1003_1B; 254 mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX; 255 goto yesno; 256 case _SC_DELAYTIMER_MAX: 257 mib[0] = CTL_P1003_1B; 258 mib[1] = CTL_P1003_1B_DELAYTIMER_MAX; 259 goto yesno; 260 case _SC_MQ_OPEN_MAX: 261 mib[0] = CTL_P1003_1B; 262 mib[1] = CTL_P1003_1B_MQ_OPEN_MAX; 263 goto yesno; 264 case _SC_PAGESIZE: 265 defaultresult = getpagesize(); 266 mib[0] = CTL_P1003_1B; 267 mib[1] = CTL_P1003_1B_PAGESIZE; 268 goto yesno; 269 case _SC_RTSIG_MAX: 270 mib[0] = CTL_P1003_1B; 271 mib[1] = CTL_P1003_1B_RTSIG_MAX; 272 goto yesno; 273 case _SC_SEM_NSEMS_MAX: 274 mib[0] = CTL_P1003_1B; 275 mib[1] = CTL_P1003_1B_SEM_NSEMS_MAX; 276 goto yesno; 277 case _SC_SEM_VALUE_MAX: 278 mib[0] = CTL_P1003_1B; 279 mib[1] = CTL_P1003_1B_SEM_VALUE_MAX; 280 goto yesno; 281 case _SC_SIGQUEUE_MAX: 282 mib[0] = CTL_P1003_1B; 283 mib[1] = CTL_P1003_1B_SIGQUEUE_MAX; 284 goto yesno; 285 case _SC_TIMER_MAX: 286 mib[0] = CTL_P1003_1B; 287 mib[1] = CTL_P1003_1B_TIMER_MAX; 288 goto yesno; 289 #endif /* _P1003_1B_VISIBLE */ 290 291 yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) 292 return (-1); 293 if (value == 0) 294 return (defaultresult); 295 return (value); 296 break; 297 default: 298 errno = EINVAL; 299 return (-1); 300 } 301 return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); 302 } 303