1/* $OpenBSD: sysconf.c,v 1.28 2022/07/19 09:25:44 claudio Exp $ */ 2/*- 3 * Copyright (c) 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * Sean Eric Fagan of Cygnus Support. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#include <sys/types.h> 35#include <sys/sem.h> 36#include <sys/sysctl.h> 37#include <sys/time.h> 38#include <sys/resource.h> 39#include <sys/socket.h> 40 41#include <errno.h> 42#include <grp.h> 43#include <pthread.h> 44#include <pwd.h> 45#include <stdio.h> 46#include <unistd.h> 47 48/* 49 * sysconf -- 50 * get configurable system variables. 51 * 52 * XXX 53 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 54 * not change during the lifetime of the calling process. This would seem 55 * to require that any change to system limits kill all running processes. 56 * A workaround might be to cache the values when they are first retrieved 57 * and then simply return the cached value on subsequent calls. This is 58 * less useful than returning up-to-date values, however. 59 */ 60long 61sysconf(int name) 62{ 63 struct rlimit rl; 64 size_t len; 65 int mib[3], value, namelen, sverrno; 66 67 len = sizeof(value); 68 namelen = 2; 69 70 switch (name) { 71/* 1003.1 */ 72 case _SC_ARG_MAX: 73 mib[0] = CTL_KERN; 74 mib[1] = KERN_ARGMAX; 75 break; 76 case _SC_CHILD_MAX: 77 if (getrlimit(RLIMIT_NPROC, &rl) != 0) 78 return (-1); 79 if (rl.rlim_cur == RLIM_INFINITY) 80 return (-1); 81 if (rl.rlim_cur > LONG_MAX) { 82 errno = EOVERFLOW; 83 return (-1); 84 } 85 return ((long)rl.rlim_cur); 86 case _SC_CLK_TCK: 87 return (CLK_TCK); 88 case _SC_JOB_CONTROL: 89 return (_POSIX_JOB_CONTROL); 90 case _SC_NGROUPS_MAX: 91 mib[0] = CTL_KERN; 92 mib[1] = KERN_NGROUPS; 93 break; 94 case _SC_OPEN_MAX: 95 if (getrlimit(RLIMIT_NOFILE, &rl) != 0) 96 return (-1); 97 if (rl.rlim_cur == RLIM_INFINITY) 98 return (-1); 99 if (rl.rlim_cur > LONG_MAX) { 100 errno = EOVERFLOW; 101 return (-1); 102 } 103 return ((long)rl.rlim_cur); 104 case _SC_STREAM_MAX: 105 if (getrlimit(RLIMIT_NOFILE, &rl) != 0) 106 return (-1); 107 if (rl.rlim_cur == RLIM_INFINITY) 108 return (-1); 109 if (rl.rlim_cur > LONG_MAX) { 110 errno = EOVERFLOW; 111 return (-1); 112 } 113 /* 114 * struct __sFILE currently has a limitation that 115 * file descriptors must fit in a signed short. 116 * This doesn't precisely capture the letter of POSIX 117 * but approximates the spirit. 118 */ 119 if (rl.rlim_cur > SHRT_MAX) 120 return (SHRT_MAX); 121 122 return ((long)rl.rlim_cur); 123 case _SC_TZNAME_MAX: 124 return (NAME_MAX); 125 case _SC_SAVED_IDS: 126 return (_POSIX_SAVED_IDS); 127 case _SC_VERSION: 128 mib[0] = CTL_KERN; 129 mib[1] = KERN_POSIX1; 130 break; 131 132/* 1003.1b */ 133 case _SC_PAGESIZE: 134 if (_pagesize != 0) 135 return (_pagesize); 136 mib[0] = CTL_HW; 137 mib[1] = HW_PAGESIZE; 138 break; 139 case _SC_FSYNC: 140 return (_POSIX_FSYNC); 141 142/* 1003.1c */ 143 case _SC_LOGIN_NAME_MAX: 144 return (LOGIN_NAME_MAX); 145 146 case _SC_THREAD_SAFE_FUNCTIONS: 147 return (_POSIX_THREAD_SAFE_FUNCTIONS); 148 149 case _SC_GETGR_R_SIZE_MAX: 150 return (_GR_BUF_LEN); 151 152 case _SC_GETPW_R_SIZE_MAX: 153 return (_PW_BUF_LEN); 154 155/* 1003.2 */ 156 case _SC_BC_BASE_MAX: 157 return (BC_BASE_MAX); 158 case _SC_BC_DIM_MAX: 159 return (BC_DIM_MAX); 160 case _SC_BC_SCALE_MAX: 161 return (BC_SCALE_MAX); 162 case _SC_BC_STRING_MAX: 163 return (BC_STRING_MAX); 164 case _SC_COLL_WEIGHTS_MAX: 165 return (COLL_WEIGHTS_MAX); 166 case _SC_EXPR_NEST_MAX: 167 return (EXPR_NEST_MAX); 168 case _SC_LINE_MAX: 169 return (LINE_MAX); 170 case _SC_RE_DUP_MAX: 171 return (RE_DUP_MAX); 172 case _SC_2_VERSION: 173 return (_POSIX2_VERSION); 174 case _SC_2_C_BIND: 175 return (_POSIX2_C_BIND); 176 case _SC_2_C_DEV: 177 return (_POSIX2_C_DEV); 178 case _SC_2_CHAR_TERM: 179 return (_POSIX2_CHAR_TERM); 180 case _SC_2_FORT_DEV: 181 return (_POSIX2_FORT_DEV); 182 case _SC_2_FORT_RUN: 183 return (_POSIX2_FORT_RUN); 184 case _SC_2_LOCALEDEF: 185 return (_POSIX2_LOCALEDEF); 186 case _SC_2_SW_DEV: 187 return (_POSIX2_SW_DEV); 188 case _SC_2_UPE: 189 return (_POSIX2_UPE); 190 191/* XPG 4.2 */ 192 case _SC_XOPEN_SHM: 193 mib[0] = CTL_KERN; 194 mib[1] = KERN_SYSVSHM; 195 if (sysctl(mib, namelen, &value, &len, NULL, 0) == -1) 196 return (-1); 197 if (value == 0) 198 return (-1); 199 return (value); 200 break; 201 case _SC_SEM_NSEMS_MAX: 202 return (-1); 203 case _SC_SEM_VALUE_MAX: 204 return (SEM_VALUE_MAX); 205 206/* Unsorted */ 207 case _SC_HOST_NAME_MAX: 208 return (HOST_NAME_MAX); /* does not include \0 */ 209 case _SC_MONOTONIC_CLOCK: 210 return (_POSIX_MONOTONIC_CLOCK); 211 case _SC_2_PBS: 212 case _SC_2_PBS_ACCOUNTING: 213 case _SC_2_PBS_CHECKPOINT: 214 case _SC_2_PBS_LOCATE: 215 case _SC_2_PBS_MESSAGE: 216 case _SC_2_PBS_TRACK: 217 return (_POSIX2_PBS); 218 case _SC_ADVISORY_INFO: 219 return (_POSIX_ADVISORY_INFO); 220 case _SC_AIO_LISTIO_MAX: 221 case _SC_AIO_MAX: 222 case _SC_AIO_PRIO_DELTA_MAX: 223 return (-1); 224 case _SC_ASYNCHRONOUS_IO: 225 return (_POSIX_ASYNCHRONOUS_IO); 226 case _SC_ATEXIT_MAX: 227 return (-1); 228 case _SC_BARRIERS: 229 return (_POSIX_BARRIERS); 230 case _SC_CLOCK_SELECTION: 231 return (_POSIX_CLOCK_SELECTION); 232 case _SC_CPUTIME: 233 return (_POSIX_CPUTIME); 234 case _SC_DELAYTIMER_MAX: 235 return (-1); 236 case _SC_IOV_MAX: 237 return (IOV_MAX); 238 case _SC_IPV6: 239#if _POSIX_IPV6 == 0 240 sverrno = errno; 241 mib[0] = CTL_NET; 242 mib[1] = PF_INET6; 243 mib[2] = 0; 244 namelen = 3; 245 value = 0; 246 if (sysctl(mib, 3, NULL, 0, NULL, 0) == -1) 247 value = errno; 248 errno = sverrno; 249 if (value != ENOPROTOOPT) 250 return (200112L); 251 else 252 return (0); 253#else 254 return (_POSIX_IPV6); 255#endif 256 case _SC_MAPPED_FILES: 257 return (_POSIX_MAPPED_FILES); 258 case _SC_MEMLOCK: 259 return (_POSIX_MEMLOCK); 260 case _SC_MEMLOCK_RANGE: 261 return (_POSIX_MEMLOCK_RANGE); 262 case _SC_MEMORY_PROTECTION: 263 return (_POSIX_MEMORY_PROTECTION); 264 case _SC_MESSAGE_PASSING: 265 return (_POSIX_MESSAGE_PASSING); 266 case _SC_PRIORITIZED_IO: 267 return (_POSIX_PRIORITIZED_IO); 268 case _SC_PRIORITY_SCHEDULING: 269 return (_POSIX_PRIORITY_SCHEDULING); 270 case _SC_RAW_SOCKETS: 271 return (_POSIX_RAW_SOCKETS); 272 case _SC_READER_WRITER_LOCKS: 273 return (_POSIX_READER_WRITER_LOCKS); 274 case _SC_REALTIME_SIGNALS: 275 return (_POSIX_REALTIME_SIGNALS); 276 case _SC_REGEXP: 277 return (_POSIX_REGEXP); 278 case _SC_SEMAPHORES: 279 return (_POSIX_SEMAPHORES); 280 case _SC_SHARED_MEMORY_OBJECTS: 281 return (_POSIX_SHARED_MEMORY_OBJECTS); 282 case _SC_SHELL: 283 return (_POSIX_SHELL); 284 case _SC_SIGQUEUE_MAX: 285 return (-1); 286 case _SC_SPAWN: 287 return (_POSIX_SPAWN); 288 case _SC_SPIN_LOCKS: 289 return (_POSIX_SPIN_LOCKS); 290 case _SC_SPORADIC_SERVER: 291 return (_POSIX_SPORADIC_SERVER); 292 case _SC_SYNCHRONIZED_IO: 293 return (_POSIX_SYNCHRONIZED_IO); 294 case _SC_SYMLOOP_MAX: 295 return (SYMLOOP_MAX); 296 case _SC_THREAD_ATTR_STACKADDR: 297 return (_POSIX_THREAD_ATTR_STACKADDR); 298 case _SC_THREAD_ATTR_STACKSIZE: 299 return (_POSIX_THREAD_ATTR_STACKSIZE); 300 case _SC_THREAD_CPUTIME: 301 return (_POSIX_THREAD_CPUTIME); 302 case _SC_THREAD_DESTRUCTOR_ITERATIONS: 303 return (PTHREAD_DESTRUCTOR_ITERATIONS); 304 case _SC_THREAD_KEYS_MAX: 305 return (PTHREAD_KEYS_MAX); 306 case _SC_THREAD_PRIO_INHERIT: 307 return (_POSIX_THREAD_PRIO_INHERIT); 308 case _SC_THREAD_PRIO_PROTECT: 309 return (_POSIX_THREAD_PRIO_PROTECT); 310 case _SC_THREAD_PRIORITY_SCHEDULING: 311 return (_POSIX_THREAD_PRIORITY_SCHEDULING); 312 case _SC_THREAD_PROCESS_SHARED: 313 return (_POSIX_THREAD_PROCESS_SHARED); 314 case _SC_THREAD_ROBUST_PRIO_INHERIT: 315 return (_POSIX_THREAD_ROBUST_PRIO_INHERIT); 316 case _SC_THREAD_ROBUST_PRIO_PROTECT: 317 return (_POSIX_THREAD_ROBUST_PRIO_PROTECT); 318 case _SC_THREAD_SPORADIC_SERVER: 319 return (_POSIX_THREAD_SPORADIC_SERVER); 320 case _SC_THREAD_STACK_MIN: 321 return (PTHREAD_STACK_MIN); 322 case _SC_THREAD_THREADS_MAX: 323 return (PTHREAD_THREADS_MAX); 324 case _SC_THREADS: 325 return (_POSIX_THREADS); 326 case _SC_TIMEOUTS: 327 return (_POSIX_TIMEOUTS); 328 case _SC_TIMER_MAX: 329 return (-1); 330 case _SC_TIMERS: 331 return (_POSIX_TIMERS); 332 case _SC_TRACE: 333 case _SC_TRACE_EVENT_FILTER: 334 case _SC_TRACE_EVENT_NAME_MAX: 335 case _SC_TRACE_INHERIT: 336 case _SC_TRACE_LOG: 337 return (_POSIX_TRACE); 338 case _SC_TTY_NAME_MAX: 339 return (TTY_NAME_MAX); 340 case _SC_TYPED_MEMORY_OBJECTS: 341 return (_POSIX_TYPED_MEMORY_OBJECTS); 342 case _SC_V6_ILP32_OFF32: 343 return (_POSIX_V6_ILP32_OFF32); 344 case _SC_V6_ILP32_OFFBIG: 345#if _POSIX_V6_ILP32_OFFBIG == 0 346 if (sizeof(int) * CHAR_BIT == 32 && 347 sizeof(long) * CHAR_BIT == 32 && 348 sizeof(void *) * CHAR_BIT == 32 && 349 sizeof(off_t) * CHAR_BIT >= 64) 350 return 1; 351 else 352 return -1; 353#else 354 return (_POSIX_V6_ILP32_OFFBIG); 355#endif 356 case _SC_V6_LP64_OFF64: 357#if _POSIX_V6_LP64_OFF64 == 0 358 if (sizeof(int) * CHAR_BIT == 32 && 359 sizeof(long) * CHAR_BIT == 64 && 360 sizeof(void *) * CHAR_BIT == 64 && 361 sizeof(off_t) * CHAR_BIT == 64) 362 return 1; 363 else 364 return -1; 365#else 366 return (_POSIX_V6_LP64_OFF64); 367#endif 368 case _SC_V6_LPBIG_OFFBIG: 369#if _POSIX_V6_LPBIG_OFFBIG == 0 370 if (sizeof(int) * CHAR_BIT >= 32 && 371 sizeof(long) * CHAR_BIT >= 64 && 372 sizeof(void *) * CHAR_BIT >= 64 && 373 sizeof(off_t) * CHAR_BIT >= 64) 374 return 1; 375 else 376 return -1; 377#else 378 return (_POSIX_V6_LPBIG_OFFBIG); 379#endif 380 case _SC_V7_ILP32_OFF32: 381 return (_POSIX_V7_ILP32_OFF32); 382 case _SC_V7_ILP32_OFFBIG: 383#if _POSIX_V7_ILP32_OFFBIG == 0 384 if (sizeof(int) * CHAR_BIT == 32 && 385 sizeof(long) * CHAR_BIT == 32 && 386 sizeof(void *) * CHAR_BIT == 32 && 387 sizeof(off_t) * CHAR_BIT >= 64) 388 return 1; 389 else 390 return -1; 391#else 392 return (_POSIX_V7_ILP32_OFFBIG); 393#endif 394 case _SC_V7_LP64_OFF64: 395#if _POSIX_V7_LP64_OFF64 == 0 396 if (sizeof(int) * CHAR_BIT == 32 && 397 sizeof(long) * CHAR_BIT == 64 && 398 sizeof(void *) * CHAR_BIT == 64 && 399 sizeof(off_t) * CHAR_BIT == 64) 400 return 1; 401 else 402 return -1; 403#else 404 return (_POSIX_V7_LP64_OFF64); 405#endif 406 case _SC_V7_LPBIG_OFFBIG: 407#if _POSIX_V7_LPBIG_OFFBIG == 0 408 if (sizeof(int) * CHAR_BIT >= 32 && 409 sizeof(long) * CHAR_BIT >= 64 && 410 sizeof(void *) * CHAR_BIT >= 64 && 411 sizeof(off_t) * CHAR_BIT >= 64) 412 return 1; 413 else 414 return -1; 415#else 416 return (_POSIX_V7_LPBIG_OFFBIG); 417#endif 418 case _SC_XOPEN_CRYPT: 419 return (_XOPEN_CRYPT); 420 case _SC_XOPEN_ENH_I18N: 421 return (_XOPEN_ENH_I18N); 422 case _SC_XOPEN_LEGACY: 423 return (_XOPEN_LEGACY); 424 case _SC_XOPEN_REALTIME: 425 return (_XOPEN_REALTIME); 426 case _SC_XOPEN_REALTIME_THREADS: 427 return (_XOPEN_REALTIME_THREADS); 428 case _SC_XOPEN_STREAMS: 429 return (_XOPEN_STREAMS); 430 case _SC_XOPEN_UNIX: 431 return (_XOPEN_UNIX); 432 case _SC_XOPEN_UUCP: 433 return (_XOPEN_UUCP); 434#ifdef _XOPEN_VERSION 435 case _SC_XOPEN_VERSION: 436 return (_XOPEN_VERSION); 437#endif 438 439/* Extensions */ 440 case _SC_PHYS_PAGES: 441 { 442 int64_t physmem; 443 444 mib[0] = CTL_HW; 445 mib[1] = HW_PHYSMEM64; 446 len = sizeof(physmem); 447 if (sysctl(mib, namelen, &physmem, &len, NULL, 0) == -1) 448 return (-1); 449 return (physmem / getpagesize()); 450 } 451 case _SC_AVPHYS_PAGES: 452 { 453 struct uvmexp uvmexp; 454 455 mib[0] = CTL_VM; 456 mib[1] = VM_UVMEXP; 457 len = sizeof(uvmexp); 458 if (sysctl(mib, namelen, &uvmexp, &len, NULL, 0) == -1) 459 return (-1); 460 return (uvmexp.free); 461 } 462 463 case _SC_NPROCESSORS_CONF: 464 mib[0] = CTL_HW; 465 mib[1] = HW_NCPU; 466 break; 467 case _SC_NPROCESSORS_ONLN: 468 mib[0] = CTL_HW; 469 mib[1] = HW_NCPUONLINE; 470 break; 471 472 default: 473 errno = EINVAL; 474 return (-1); 475 } 476 return (sysctl(mib, namelen, &value, &len, NULL, 0) == -1 ? -1 : value); 477} 478DEF_WEAK(sysconf); 479