3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Sean Eric Fagan of Cygnus Support.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * @(#)sysconf.c 8.2 (Berkeley) 3/20/94
33 * $FreeBSD: src/lib/libc/gen/sysconf.c,v 1.26 2008/02/27 05:56:57 wollman Exp $
36 #include <sys/param.h>
38 #include <sys/sysctl.h>
39 #include <sys/resource.h>
40 #include <sys/socket.h>
45 #include <pthread.h> /* we just need the limits */
46 #include <semaphore.h>
50 #include "../stdlib/atexit.h"
51 #include "../stdtime/tzfile.h"
53 #define _PATH_ZONEINFO TZDIR /* from tzfile.h */
57 * get configurable system variables.
60 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values
61 * not change during the lifetime of the calling process. This would seem
62 * to require that any change to system limits kill all running processes.
63 * A workaround might be to cache the values when they are first retrieved
64 * and then simply return the cached value on subsequent calls. This is
65 * less useful than returning up-to-date values, however.
72 int mib[2], sverrno, value;
73 long lvalue, defaultresult;
84 if (getrlimit(RLIMIT_NPROC, &rl) != 0)
86 if (rl.rlim_cur == RLIM_INFINITY)
88 if (rl.rlim_cur > LONG_MAX) {
92 return ((long)rl.rlim_cur);
97 mib[1] = KERN_NGROUPS;
100 if (getrlimit(RLIMIT_NOFILE, &rl) != 0)
102 if (rl.rlim_cur == RLIM_INFINITY)
104 if (rl.rlim_cur > LONG_MAX) {
108 return ((long)rl.rlim_cur);
109 case _SC_SEM_VALUE_MAX:
110 return (SEM_VALUE_MAX);
112 if (getrlimit(RLIMIT_NOFILE, &rl) != 0)
114 if (rl.rlim_cur == RLIM_INFINITY)
116 if (rl.rlim_cur > LONG_MAX) {
121 * struct __sFILE currently has a limitation that
122 * file descriptors must fit in a signed short.
123 * This doesn't precisely capture the letter of POSIX
124 * but approximates the spirit.
126 if (rl.rlim_cur > SHRT_MAX)
129 return ((long)rl.rlim_cur);
130 case _SC_JOB_CONTROL:
131 return (_POSIX_JOB_CONTROL);
133 /* XXX - must be 1 */
135 mib[1] = KERN_SAVED_IDS;
139 mib[1] = KERN_POSIX1;
141 case _SC_BC_BASE_MAX:
142 return (BC_BASE_MAX);
145 case _SC_BC_SCALE_MAX:
146 return (BC_SCALE_MAX);
147 case _SC_BC_STRING_MAX:
148 return (BC_STRING_MAX);
149 case _SC_COLL_WEIGHTS_MAX:
150 return (COLL_WEIGHTS_MAX);
151 case _SC_EXPR_NEST_MAX:
152 return (EXPR_NEST_MAX);
159 * This is something of a lie, but it would be silly at
160 * this point to try to deduce this from the contents
163 return (_POSIX2_VERSION);
165 return (_POSIX2_C_BIND);
167 return (_POSIX2_C_DEV);
168 case _SC_2_CHAR_TERM:
169 return (_POSIX2_CHAR_TERM);
171 return (_POSIX2_FORT_DEV);
173 return (_POSIX2_FORT_RUN);
174 case _SC_2_LOCALEDEF:
175 return (_POSIX2_LOCALEDEF);
177 return (_POSIX2_SW_DEV);
179 return (_POSIX2_UPE);
181 path = _PATH_ZONEINFO;
185 lvalue = pathconf(path, _PC_NAME_MAX);
186 if (lvalue == -1 && errno != 0)
191 case _SC_ASYNCHRONOUS_IO:
192 #if _POSIX_ASYNCHRONOUS_IO == 0
193 mib[0] = CTL_P1003_1B;
194 mib[1] = CTL_P1003_1B_ASYNCHRONOUS_IO;
197 return (_POSIX_ASYNCHRONOUS_IO);
199 case _SC_MAPPED_FILES:
200 return (_POSIX_MAPPED_FILES);
202 return (_POSIX_MEMLOCK);
203 case _SC_MEMLOCK_RANGE:
204 return (_POSIX_MEMLOCK_RANGE);
205 case _SC_MEMORY_PROTECTION:
206 return (_POSIX_MEMORY_PROTECTION);
207 case _SC_MESSAGE_PASSING:
208 return (_POSIX_MESSAGE_PASSING);
209 case _SC_PRIORITIZED_IO:
210 #if _POSIX_PRIORITIZED_IO == 0
211 mib[0] = CTL_P1003_1B;
212 mib[1] = CTL_P1003_1B_PRIORITIZED_IO;
215 return (_POSIX_PRIORITIZED_IO);
217 case _SC_PRIORITY_SCHEDULING:
218 #if _POSIX_PRIORITY_SCHEDULING == 0
219 mib[0] = CTL_P1003_1B;
220 mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING;
223 return (_POSIX_PRIORITY_SCHEDULING);
225 case _SC_REALTIME_SIGNALS:
226 #if _POSIX_REALTIME_SIGNALS == 0
227 mib[0] = CTL_P1003_1B;
228 mib[1] = CTL_P1003_1B_REALTIME_SIGNALS;
231 return (_POSIX_REALTIME_SIGNALS);
234 #if _POSIX_SEMAPHORES == 0
235 mib[0] = CTL_P1003_1B;
236 mib[1] = CTL_P1003_1B_SEMAPHORES;
239 return (_POSIX_SEMAPHORES);
242 return (_POSIX_FSYNC);
244 case _SC_SHARED_MEMORY_OBJECTS:
245 return (_POSIX_SHARED_MEMORY_OBJECTS);
246 case _SC_SYNCHRONIZED_IO:
247 #if _POSIX_SYNCHRONIZED_IO == 0
248 mib[0] = CTL_P1003_1B;
249 mib[1] = CTL_P1003_1B_SYNCHRONIZED_IO;
252 return (_POSIX_SYNCHRONIZED_IO);
255 #if _POSIX_TIMERS == 0
256 mib[0] = CTL_P1003_1B;
257 mib[1] = CTL_P1003_1B_TIMERS;
260 return (_POSIX_TIMERS);
262 case _SC_AIO_LISTIO_MAX:
263 mib[0] = CTL_P1003_1B;
264 mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX;
267 mib[0] = CTL_P1003_1B;
268 mib[1] = CTL_P1003_1B_AIO_MAX;
270 case _SC_AIO_PRIO_DELTA_MAX:
271 mib[0] = CTL_P1003_1B;
272 mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX;
274 case _SC_DELAYTIMER_MAX:
275 mib[0] = CTL_P1003_1B;
276 mib[1] = CTL_P1003_1B_DELAYTIMER_MAX;
279 defaultresult = getpagesize();
280 mib[0] = CTL_P1003_1B;
281 mib[1] = CTL_P1003_1B_PAGESIZE;
284 mib[0] = CTL_P1003_1B;
285 mib[1] = CTL_P1003_1B_RTSIG_MAX;
287 case _SC_SEM_NSEMS_MAX:
288 mib[0] = CTL_P1003_1B;
289 mib[1] = CTL_P1003_1B_SEM_NSEMS_MAX;
291 case _SC_SIGQUEUE_MAX:
292 mib[0] = CTL_P1003_1B;
293 mib[1] = CTL_P1003_1B_SIGQUEUE_MAX;
296 mib[0] = CTL_P1003_1B;
297 mib[1] = CTL_P1003_1B_TIMER_MAX;
300 if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
303 return (defaultresult);
304 return ((long)value);
307 case _SC_2_PBS_ACCOUNTING:
308 case _SC_2_PBS_CHECKPOINT:
309 case _SC_2_PBS_LOCATE:
310 case _SC_2_PBS_MESSAGE:
311 case _SC_2_PBS_TRACK:
313 #error "don't know how to determine _SC_2_PBS"
315 * This probably requires digging through the filesystem
316 * to see if the appropriate package has been installed.
317 * Since we don't currently support this option at all,
318 * it's not worth the effort to write the code now.
319 * Figuring out which of the sub-options are supported
320 * would be even more difficult, so it's probably easier
321 * to always say ``no''.
324 return (_POSIX2_PBS);
326 case _SC_ADVISORY_INFO:
327 #if _POSIX_ADVISORY_INFO == 0
328 #error "_POSIX_ADVISORY_INFO"
330 return (_POSIX_ADVISORY_INFO);
333 #if _POSIX_BARRIERS == 0
334 #error "_POSIX_BARRIERS"
336 return (_POSIX_BARRIERS);
338 case _SC_CLOCK_SELECTION:
339 #if _POSIX_CLOCK_SELECTION == 0
340 #error "_POSIX_CLOCK_SELECTION"
342 return (_POSIX_CLOCK_SELECTION);
345 #if _POSIX_CPUTIME == 0
346 #error "_POSIX_CPUTIME"
348 return (_POSIX_CPUTIME);
351 case _SC_FILE_LOCKING:
353 * XXX - The standard doesn't tell us how to define
354 * _POSIX_FILE_LOCKING, so we can't answer this one.
357 case _SC_GETGR_R_SIZE_MAX:
358 case _SC_GETPW_R_SIZE_MAX:
360 case _SC_HOST_NAME_MAX:
361 return (MAXHOSTNAMELEN - 1); /* does not include \0 */
362 case _SC_LOGIN_NAME_MAX:
364 case _SC_MONOTONIC_CLOCK:
365 #if _POSIX_MONOTONIC_CLOCK == 0
366 #error "_POSIX_MONOTONIC_CLOCK"
368 return (_POSIX_MONOTONIC_CLOCK);
370 case _SC_MQ_OPEN_MAX:
371 len = sizeof(lvalue);
372 if (sysctlbyname("kern.mqueue.mq_open_max", &lvalue, &len,
377 case _SC_MQ_PRIO_MAX:
378 len = sizeof(lvalue);
379 if (sysctlbyname("kern.mqueue.mq_prio_max", &lvalue, &len,
384 case _SC_READER_WRITER_LOCKS:
385 return (_POSIX_READER_WRITER_LOCKS);
387 return (_POSIX_REGEXP);
389 return (_POSIX_SHELL);
391 return (_POSIX_SPAWN);
393 return (_POSIX_SPIN_LOCKS);
394 case _SC_SPORADIC_SERVER:
395 #if _POSIX_SPORADIC_SERVER == 0
396 #error "_POSIX_SPORADIC_SERVER"
398 return (_POSIX_SPORADIC_SERVER);
400 case _SC_THREAD_ATTR_STACKADDR:
401 return (_POSIX_THREAD_ATTR_STACKADDR);
402 case _SC_THREAD_ATTR_STACKSIZE:
403 return (_POSIX_THREAD_ATTR_STACKSIZE);
404 case _SC_THREAD_CPUTIME:
405 return (_POSIX_THREAD_CPUTIME);
406 case _SC_THREAD_DESTRUCTOR_ITERATIONS:
407 return (PTHREAD_DESTRUCTOR_ITERATIONS);
408 case _SC_THREAD_KEYS_MAX:
409 return (PTHREAD_KEYS_MAX);
410 case _SC_THREAD_PRIO_INHERIT:
411 return (_POSIX_THREAD_PRIO_INHERIT);
412 case _SC_THREAD_PRIO_PROTECT:
413 return (_POSIX_THREAD_PRIO_PROTECT);
414 case _SC_THREAD_PRIORITY_SCHEDULING:
415 return (_POSIX_THREAD_PRIORITY_SCHEDULING);
416 case _SC_THREAD_PROCESS_SHARED:
417 return (_POSIX_THREAD_PROCESS_SHARED);
418 case _SC_THREAD_ROBUST_PRIO_INHERIT:
419 return (_POSIX_THREAD_ROBUST_PRIO_INHERIT);
420 case _SC_THREAD_ROBUST_PRIO_PROTECT:
421 return (_POSIX_THREAD_ROBUST_PRIO_PROTECT);
422 case _SC_THREAD_SAFE_FUNCTIONS:
423 return (_POSIX_THREAD_SAFE_FUNCTIONS);
424 case _SC_THREAD_SPORADIC_SERVER:
425 return (_POSIX_THREAD_SPORADIC_SERVER);
426 case _SC_THREAD_STACK_MIN:
427 return (PTHREAD_STACK_MIN);
428 case _SC_THREAD_THREADS_MAX:
429 return (PTHREAD_THREADS_MAX); /* XXX wrong type! */
431 return (_POSIX_TIMEOUTS);
433 return (_POSIX_THREADS);
435 #if _POSIX_TRACE == 0
436 #error "_POSIX_TRACE"
437 /* While you're implementing this, also do the ones below. */
439 return (_POSIX_TRACE);
441 #if _POSIX_TRACE > -1
442 case _SC_TRACE_EVENT_FILTER:
443 return (_POSIX_TRACE_EVENT_FILTER);
444 case _SC_TRACE_INHERIT:
445 return (_POSIX_TRACE_INHERIT);
447 return (_POSIX_TRACE_LOG);
449 case _SC_TTY_NAME_MAX:
452 case _SC_TYPED_MEMORY_OBJECTS:
453 #if _POSIX_TYPED_MEMORY_OBJECTS == 0
454 #error "_POSIX_TYPED_MEMORY_OBJECTS"
456 return (_POSIX_TYPED_MEMORY_OBJECTS);
458 case _SC_V6_ILP32_OFF32:
459 #if _V6_ILP32_OFF32 == 0
460 if (sizeof(int) * CHAR_BIT == 32 &&
461 sizeof(int) == sizeof(long) &&
462 sizeof(long) == sizeof(void *) &&
463 sizeof(void *) == sizeof(off_t))
468 return (_V6_ILP32_OFF32);
470 case _SC_V6_ILP32_OFFBIG:
471 #if _V6_ILP32_OFFBIG == 0
472 if (sizeof(int) * CHAR_BIT == 32 &&
473 sizeof(int) == sizeof(long) &&
474 sizeof(long) == sizeof(void *) &&
475 sizeof(off_t) * CHAR_BIT >= 64)
480 return (_V6_ILP32_OFFBIG);
482 case _SC_V6_LP64_OFF64:
483 #if _V6_LP64_OFF64 == 0
484 if (sizeof(int) * CHAR_BIT == 32 &&
485 sizeof(long) * CHAR_BIT == 64 &&
486 sizeof(long) == sizeof(void *) &&
487 sizeof(void *) == sizeof(off_t))
492 return (_V6_LP64_OFF64);
494 case _SC_V6_LPBIG_OFFBIG:
495 #if _V6_LPBIG_OFFBIG == 0
496 if (sizeof(int) * CHAR_BIT >= 32 &&
497 sizeof(long) * CHAR_BIT >= 64 &&
498 sizeof(void *) * CHAR_BIT >= 64 &&
499 sizeof(off_t) * CHAR_BIT >= 64)
504 return (_V6_LPBIG_OFFBIG);
506 case _SC_V7_ILP32_OFF32:
507 #if _V7_ILP32_OFF32 == 0
508 if (sizeof(int) * CHAR_BIT == 32 &&
509 sizeof(int) == sizeof(long) &&
510 sizeof(long) == sizeof(void *) &&
511 sizeof(void *) == sizeof(off_t))
516 return (_V7_ILP32_OFF32);
518 case _SC_V7_ILP32_OFFBIG:
519 #if _V7_ILP32_OFFBIG == 0
520 if (sizeof(int) * CHAR_BIT == 32 &&
521 sizeof(int) == sizeof(long) &&
522 sizeof(long) == sizeof(void *) &&
523 sizeof(off_t) * CHAR_BIT >= 64)
528 return (_V7_ILP32_OFFBIG);
530 case _SC_V7_LP64_OFF64:
531 #if _V7_LP64_OFF64 == 0
532 if (sizeof(int) * CHAR_BIT == 32 &&
533 sizeof(long) * CHAR_BIT == 64 &&
534 sizeof(long) == sizeof(void *) &&
535 sizeof(void *) == sizeof(off_t))
540 return (_V7_LP64_OFF64);
542 case _SC_V7_LPBIG_OFFBIG:
543 #if _V7_LPBIG_OFFBIG == 0
544 if (sizeof(int) * CHAR_BIT >= 32 &&
545 sizeof(long) * CHAR_BIT >= 64 &&
546 sizeof(void *) * CHAR_BIT >= 64 &&
547 sizeof(off_t) * CHAR_BIT >= 64)
552 return (_V7_LPBIG_OFFBIG);
555 return (ATEXIT_SIZE);
558 mib[1] = KERN_IOV_MAX;
560 case _SC_XOPEN_CRYPT:
561 return (_XOPEN_CRYPT);
562 case _SC_XOPEN_ENH_I18N:
563 return (_XOPEN_ENH_I18N);
564 case _SC_XOPEN_LEGACY:
565 return (_XOPEN_LEGACY);
566 case _SC_XOPEN_REALTIME:
567 #if _XOPEN_REALTIME == 0
569 value = sysconf(_SC_ASYNCHRONOUS_IO) > 0 &&
570 sysconf(_SC_MEMLOCK) > 0 &&
571 sysconf(_SC_MEMLOCK_RANGE) > 0 &&
572 sysconf(_SC_MESSAGE_PASSING) > 0 &&
573 sysconf(_SC_PRIORITY_SCHEDULING) > 0 &&
574 sysconf(_SC_REALTIME_SIGNALS) > 0 &&
575 sysconf(_SC_SEMAPHORES) > 0 &&
576 sysconf(_SC_SHARED_MEMORY_OBJECTS) > 0 &&
577 sysconf(_SC_SYNCHRONIZED_IO) > 0 &&
578 sysconf(_SC_TIMERS) > 0;
585 return (_XOPEN_REALTIME);
587 case _SC_XOPEN_REALTIME_THREADS:
588 #if _XOPEN_REALTIME_THREADS == 0
589 #error "_XOPEN_REALTIME_THREADS"
591 return (_XOPEN_REALTIME_THREADS);
595 case _SC_XOPEN_STREAMS:
596 return (_XOPEN_STREAMS);
598 return (_XOPEN_UNIX);
599 #ifdef _XOPEN_VERSION
600 case _SC_XOPEN_VERSION:
601 return (_XOPEN_VERSION);
603 #ifdef _XOPEN_XCU_VERSION
604 case _SC_XOPEN_XCU_VERSION:
605 return (_XOPEN_XCU_VERSION);
607 case _SC_SYMLOOP_MAX:
608 return (MAXSYMLINKS);
609 case _SC_RAW_SOCKETS:
610 return (_POSIX_RAW_SOCKETS);
614 value = socket(PF_INET6, SOCK_DGRAM, 0);
622 return (_POSIX_IPV6);
625 case _SC_NPROCESSORS_CONF:
626 case _SC_NPROCESSORS_ONLN:
631 #ifdef _SC_PHYS_PAGES
633 len = sizeof(lvalue);
634 if (sysctlbyname("hw.availpages", &lvalue, &len, NULL, 0) == -1)
639 case _SC_LEVEL1_DCACHE_LINESIZE:
640 return (__VM_CACHELINE_SIZE);
647 if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
649 return ((long)value);