lib/libc/gen/sysconf.c

   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. 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.
  19  *
  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
  30  * SUCH DAMAGE.
  31  *
  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 $
  34  */
  35
  36 #include <sys/param.h>
  37 #include <sys/time.h>
  38 #include <sys/sysctl.h>
  39 #include <sys/resource.h>
  40 #include <sys/socket.h>
  41
  42 #include <errno.h>
  43 #include <limits.h>
  44 #include <paths.h>
  45 #include <pthread.h>            /* we just need the limits */
  46 #include <semaphore.h>
  47 #include <time.h>
  48 #include <unistd.h>
  49
  50 #include "../stdlib/atexit.h"
  51 #include "../stdtime/tzfile.h"
  52
  53 #define _PATH_ZONEINFO  TZDIR   /* from tzfile.h */
  54
  55 /*
  56  * sysconf --
  57  *      get configurable system variables.
  58  *
  59  * XXX
  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.
  66  */
  67 long
  68 sysconf(int name)
  69 {
  70         struct rlimit rl;
  71         size_t len;
  72         int mib[2], sverrno, value;
  73         long lvalue, defaultresult;
  74         const char *path;
  75
  76         defaultresult = -1;
  77
  78         switch (name) {
  79         case _SC_ARG_MAX:
  80                 mib[0] = CTL_KERN;
  81                 mib[1] = KERN_ARGMAX;
  82                 break;
  83         case _SC_CHILD_MAX:
  84                 if (getrlimit(RLIMIT_NPROC, &rl) != 0)
  85                         return (-1);
  86                 if (rl.rlim_cur == RLIM_INFINITY)
  87                         return (-1);
  88                 if (rl.rlim_cur > LONG_MAX) {
  89                         errno = EOVERFLOW;
  90                         return (-1);
  91                 }
  92                 return ((long)rl.rlim_cur);
  93         case _SC_CLK_TCK:
  94                 return (CLK_TCK);
  95         case _SC_NGROUPS_MAX:
  96                 mib[0] = CTL_KERN;
  97                 mib[1] = KERN_NGROUPS;
  98                 break;
  99         case _SC_OPEN_MAX:
 100                 if (getrlimit(RLIMIT_NOFILE, &rl) != 0)
 101                         return (-1);
 102                 if (rl.rlim_cur == RLIM_INFINITY)
 103                         return (-1);
 104                 if (rl.rlim_cur > LONG_MAX) {
 105                         errno = EOVERFLOW;
 106                         return (-1);
 107                 }
 108                 return ((long)rl.rlim_cur);
 109         case _SC_SEM_VALUE_MAX:
 110                 return (SEM_VALUE_MAX);
 111         case _SC_STREAM_MAX:
 112                 if (getrlimit(RLIMIT_NOFILE, &rl) != 0)
 113                         return (-1);
 114                 if (rl.rlim_cur == RLIM_INFINITY)
 115                         return (-1);
 116                 if (rl.rlim_cur > LONG_MAX) {
 117                         errno = EOVERFLOW;
 118                         return (-1);
 119                 }
 120                 /*
 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.
 125                  */
 126                 if (rl.rlim_cur > SHRT_MAX)
 127                         return (SHRT_MAX);
 128
 129                 return ((long)rl.rlim_cur);
 130         case _SC_JOB_CONTROL:
 131                 return (_POSIX_JOB_CONTROL);
 132         case _SC_SAVED_IDS:
 133                 /* XXX - must be 1 */
 134                 mib[0] = CTL_KERN;
 135                 mib[1] = KERN_SAVED_IDS;
 136                 goto yesno;
 137         case _SC_VERSION:
 138                 mib[0] = CTL_KERN;
 139                 mib[1] = KERN_POSIX1;
 140                 break;
 141         case _SC_BC_BASE_MAX:
 142                 return (BC_BASE_MAX);
 143         case _SC_BC_DIM_MAX:
 144                 return (BC_DIM_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);
 153         case _SC_LINE_MAX:
 154                 return (LINE_MAX);
 155         case _SC_RE_DUP_MAX:
 156                 return (RE_DUP_MAX);
 157         case _SC_2_VERSION:
 158                 /*
 159                  * This is something of a lie, but it would be silly at
 160                  * this point to try to deduce this from the contents
 161                  * of the filesystem.
 162                  */
 163                 return (_POSIX2_VERSION);
 164         case _SC_2_C_BIND:
 165                 return (_POSIX2_C_BIND);
 166         case _SC_2_C_DEV:
 167                 return (_POSIX2_C_DEV);
 168         case _SC_2_CHAR_TERM:
 169                 return (_POSIX2_CHAR_TERM);
 170         case _SC_2_FORT_DEV:
 171                 return (_POSIX2_FORT_DEV);
 172         case _SC_2_FORT_RUN:
 173                 return (_POSIX2_FORT_RUN);
 174         case _SC_2_LOCALEDEF:
 175                 return (_POSIX2_LOCALEDEF);
 176         case _SC_2_SW_DEV:
 177                 return (_POSIX2_SW_DEV);
 178         case _SC_2_UPE:
 179                 return (_POSIX2_UPE);
 180         case _SC_TZNAME_MAX:
 181                 path = _PATH_ZONEINFO;
 182 do_NAME_MAX:
 183                 sverrno = errno;
 184                 errno = 0;
 185                 lvalue = pathconf(path, _PC_NAME_MAX);
 186                 if (lvalue == -1 && errno != 0)
 187                         return (-1);
 188                 errno = sverrno;
 189                 return (lvalue);
 190
 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;
 195                 break;
 196 #else
 197                 return (_POSIX_ASYNCHRONOUS_IO);
 198 #endif
 199         case _SC_MAPPED_FILES:
 200                 return (_POSIX_MAPPED_FILES);
 201         case _SC_MEMLOCK:
 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;
 213                 goto yesno;
 214 #else
 215                 return (_POSIX_PRIORITIZED_IO);
 216 #endif
 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;
 221                 goto yesno;
 222 #else
 223                 return (_POSIX_PRIORITY_SCHEDULING);
 224 #endif
 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;
 229                 goto yesno;
 230 #else
 231                 return (_POSIX_REALTIME_SIGNALS);
 232 #endif
 233         case _SC_SEMAPHORES:
 234 #if _POSIX_SEMAPHORES == 0
 235                 mib[0] = CTL_P1003_1B;
 236                 mib[1] = CTL_P1003_1B_SEMAPHORES;
 237                 goto yesno;
 238 #else
 239                 return (_POSIX_SEMAPHORES);
 240 #endif
 241         case _SC_FSYNC:
 242                 return (_POSIX_FSYNC);
 243
 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;
 250                 goto yesno;
 251 #else
 252                 return (_POSIX_SYNCHRONIZED_IO);
 253 #endif
 254         case _SC_TIMERS:
 255 #if _POSIX_TIMERS == 0
 256                 mib[0] = CTL_P1003_1B;
 257                 mib[1] = CTL_P1003_1B_TIMERS;
 258                 goto yesno;
 259 #else
 260                 return (_POSIX_TIMERS);
 261 #endif
 262         case _SC_AIO_LISTIO_MAX:
 263                 mib[0] = CTL_P1003_1B;
 264                 mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX;
 265                 break;
 266         case _SC_AIO_MAX:
 267                 mib[0] = CTL_P1003_1B;
 268                 mib[1] = CTL_P1003_1B_AIO_MAX;
 269                 break;
 270         case _SC_AIO_PRIO_DELTA_MAX:
 271                 mib[0] = CTL_P1003_1B;
 272                 mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX;
 273                 break;
 274         case _SC_DELAYTIMER_MAX:
 275                 mib[0] = CTL_P1003_1B;
 276                 mib[1] = CTL_P1003_1B_DELAYTIMER_MAX;
 277                 goto yesno;
 278         case _SC_PAGESIZE:
 279                 defaultresult = getpagesize();
 280                 mib[0] = CTL_P1003_1B;
 281                 mib[1] = CTL_P1003_1B_PAGESIZE;
 282                 goto yesno;
 283         case _SC_RTSIG_MAX:
 284                 mib[0] = CTL_P1003_1B;
 285                 mib[1] = CTL_P1003_1B_RTSIG_MAX;
 286                 goto yesno;
 287         case _SC_SEM_NSEMS_MAX:
 288                 mib[0] = CTL_P1003_1B;
 289                 mib[1] = CTL_P1003_1B_SEM_NSEMS_MAX;
 290                 goto yesno;
 291         case _SC_SIGQUEUE_MAX:
 292                 mib[0] = CTL_P1003_1B;
 293                 mib[1] = CTL_P1003_1B_SIGQUEUE_MAX;
 294                 goto yesno;
 295         case _SC_TIMER_MAX:
 296                 mib[0] = CTL_P1003_1B;
 297                 mib[1] = CTL_P1003_1B_TIMER_MAX;
 298 yesno:
 299                 len = sizeof(value);
 300                 if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
 301                         return (-1);
 302                 if (value == 0)
 303                         return (defaultresult);
 304                 return ((long)value);
 305
 306         case _SC_2_PBS:
 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:
 312 #if _POSIX2_PBS == 0
 313 #error "don't know how to determine _SC_2_PBS"
 314                 /*
 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''.
 322                  */
 323 #else
 324                 return (_POSIX2_PBS);
 325 #endif
 326         case _SC_ADVISORY_INFO:
 327 #if _POSIX_ADVISORY_INFO == 0
 328 #error "_POSIX_ADVISORY_INFO"
 329 #else
 330                 return (_POSIX_ADVISORY_INFO);
 331 #endif
 332         case _SC_BARRIERS:
 333 #if _POSIX_BARRIERS == 0
 334 #error "_POSIX_BARRIERS"
 335 #else
 336                 return (_POSIX_BARRIERS);
 337 #endif
 338         case _SC_CLOCK_SELECTION:
 339 #if _POSIX_CLOCK_SELECTION == 0
 340 #error "_POSIX_CLOCK_SELECTION"
 341 #else
 342                 return (_POSIX_CLOCK_SELECTION);
 343 #endif
 344         case _SC_CPUTIME:
 345 #if _POSIX_CPUTIME == 0
 346 #error "_POSIX_CPUTIME"
 347 #else
 348                 return (_POSIX_CPUTIME);
 349 #endif
 350 #ifdef notdef
 351         case _SC_FILE_LOCKING:
 352                 /*
 353                  * XXX - The standard doesn't tell us how to define
 354                  * _POSIX_FILE_LOCKING, so we can't answer this one.
 355                  */
 356 #endif
 357         case _SC_GETGR_R_SIZE_MAX:
 358         case _SC_GETPW_R_SIZE_MAX:
 359                 return (-1);
 360         case _SC_HOST_NAME_MAX:
 361                 return (MAXHOSTNAMELEN - 1); /* does not include \0 */
 362         case _SC_LOGIN_NAME_MAX:
 363                 return (MAXLOGNAME);
 364         case _SC_MONOTONIC_CLOCK:
 365 #if _POSIX_MONOTONIC_CLOCK == 0
 366 #error "_POSIX_MONOTONIC_CLOCK"
 367 #else
 368                 return (_POSIX_MONOTONIC_CLOCK);
 369 #endif
 370         case _SC_MQ_OPEN_MAX:
 371                 len = sizeof(lvalue);
 372                 if (sysctlbyname("kern.mqueue.mq_open_max", &lvalue, &len,
 373                         NULL, 0) == -1)
 374                         return (-1);
 375                 return (lvalue);
 376
 377         case _SC_MQ_PRIO_MAX:
 378                 len = sizeof(lvalue);
 379                 if (sysctlbyname("kern.mqueue.mq_prio_max", &lvalue, &len,
 380                         NULL, 0) == -1)
 381                         return (-1);
 382                 return (lvalue);
 383
 384         case _SC_READER_WRITER_LOCKS:
 385                 return (_POSIX_READER_WRITER_LOCKS);
 386         case _SC_REGEXP:
 387                 return (_POSIX_REGEXP);
 388         case _SC_SHELL:
 389                 return (_POSIX_SHELL);
 390         case _SC_SPAWN:
 391                 return (_POSIX_SPAWN);
 392         case _SC_SPIN_LOCKS:
 393                 return (_POSIX_SPIN_LOCKS);
 394         case _SC_SPORADIC_SERVER:
 395 #if _POSIX_SPORADIC_SERVER == 0
 396 #error "_POSIX_SPORADIC_SERVER"
 397 #else
 398                 return (_POSIX_SPORADIC_SERVER);
 399 #endif
 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! */
 430         case _SC_TIMEOUTS:
 431                 return (_POSIX_TIMEOUTS);
 432         case _SC_THREADS:
 433                 return (_POSIX_THREADS);
 434         case _SC_TRACE:
 435 #if _POSIX_TRACE == 0
 436 #error "_POSIX_TRACE"
 437                 /* While you're implementing this, also do the ones below. */
 438 #else
 439                 return (_POSIX_TRACE);
 440 #endif
 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);
 446         case _SC_TRACE_LOG:
 447                 return (_POSIX_TRACE_LOG);
 448 #endif
 449         case _SC_TTY_NAME_MAX:
 450                 path = _PATH_DEV;
 451                 goto do_NAME_MAX;
 452         case _SC_TYPED_MEMORY_OBJECTS:
 453 #if _POSIX_TYPED_MEMORY_OBJECTS == 0
 454 #error "_POSIX_TYPED_MEMORY_OBJECTS"
 455 #else
 456                 return (_POSIX_TYPED_MEMORY_OBJECTS);
 457 #endif
 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))
 464                         return 1;
 465                 else
 466                         return -1;
 467 #else
 468                 return (_V6_ILP32_OFF32);
 469 #endif
 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)
 476                         return 1;
 477                 else
 478                         return -1;
 479 #else
 480                 return (_V6_ILP32_OFFBIG);
 481 #endif
 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))
 488                         return 1;
 489                 else
 490                         return -1;
 491 #else
 492                 return (_V6_LP64_OFF64);
 493 #endif
 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)
 500                         return 1;
 501                 else
 502                         return -1;
 503 #else
 504                 return (_V6_LPBIG_OFFBIG);
 505 #endif
 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))
 512                         return 1;
 513                 else
 514                         return -1;
 515 #else
 516                 return (_V7_ILP32_OFF32);
 517 #endif
 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)
 524                         return 1;
 525                 else
 526                         return -1;
 527 #else
 528                 return (_V7_ILP32_OFFBIG);
 529 #endif
 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))
 536                         return 1;
 537                 else
 538                         return -1;
 539 #else
 540                 return (_V7_LP64_OFF64);
 541 #endif
 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)
 548                         return 1;
 549                 else
 550                         return -1;
 551 #else
 552                 return (_V7_LPBIG_OFFBIG);
 553 #endif
 554         case _SC_ATEXIT_MAX:
 555                 return (ATEXIT_SIZE);
 556         case _SC_IOV_MAX:
 557                 mib[0] = CTL_KERN;
 558                 mib[1] = KERN_IOV_MAX;
 559                 break;
 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
 568                 sverrno = errno;
 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;
 579                 errno = sverrno;
 580                 if (value)
 581                         return (200112L);
 582                 else
 583                         return (-1);
 584 #else
 585                 return (_XOPEN_REALTIME);
 586 #endif
 587         case _SC_XOPEN_REALTIME_THREADS:
 588 #if _XOPEN_REALTIME_THREADS == 0
 589 #error "_XOPEN_REALTIME_THREADS"
 590 #else
 591                 return (_XOPEN_REALTIME_THREADS);
 592 #endif
 593         case _SC_XOPEN_SHM:
 594                 return (_XOPEN_SHM);
 595         case _SC_XOPEN_STREAMS:
 596                 return (_XOPEN_STREAMS);
 597         case _SC_XOPEN_UNIX:
 598                 return (_XOPEN_UNIX);
 599 #ifdef _XOPEN_VERSION
 600         case _SC_XOPEN_VERSION:
 601                 return (_XOPEN_VERSION);
 602 #endif
 603 #ifdef _XOPEN_XCU_VERSION
 604         case _SC_XOPEN_XCU_VERSION:
 605                 return (_XOPEN_XCU_VERSION);
 606 #endif
 607         case _SC_SYMLOOP_MAX:
 608                 return (MAXSYMLINKS);
 609         case _SC_RAW_SOCKETS:
 610                 return (_POSIX_RAW_SOCKETS);
 611         case _SC_IPV6:
 612 #if _POSIX_IPV6 == 0
 613                 sverrno = errno;
 614                 value = socket(PF_INET6, SOCK_DGRAM, 0);
 615                 errno = sverrno;
 616                 if (value >= 0) {
 617                         close(value);
 618                         return (200112L);
 619                 } else
 620                         return (0);
 621 #else
 622                 return (_POSIX_IPV6);
 623 #endif
 624
 625         case _SC_NPROCESSORS_CONF:
 626         case _SC_NPROCESSORS_ONLN:
 627                 mib[0] = CTL_HW;
 628                 mib[1] = HW_NCPU;
 629                 break;
 630
 631 #ifdef _SC_PHYS_PAGES
 632         case _SC_PHYS_PAGES:
 633                 len = sizeof(lvalue);
 634                 if (sysctlbyname("hw.availpages", &lvalue, &len, NULL, 0) == -1)
 635                         return (-1);
 636                 return (lvalue);
 637 #endif
 638
 639         case _SC_LEVEL1_DCACHE_LINESIZE:
 640                 return (__VM_CACHELINE_SIZE);
 641
 642         default:
 643                 errno = EINVAL;
 644                 return (-1);
 645         }
 646         len = sizeof(value);
 647         if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
 648                 value = -1;
 649         return ((long)value);
 650 }