gen/FreeBSD/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. 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 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD: src/lib/libc/gen/sysconf.c,v 1.20 2002/11/17 08:54:29 dougb Exp $");
  42
  43 #include <sys/param.h>
  44 #include <sys/time.h>
  45 #include <sys/sysctl.h>
  46 #include <sys/resource.h>
  47 #include <sys/socket.h>
  48 #include <sys/aio.h>
  49 #include <sys/semaphore.h>
  50
  51 #include <errno.h>
  52 #include <limits.h>
  53 #include <paths.h>
  54 #include <pthread.h>            /* we just need the limits */
  55 #include <time.h>
  56 #include <unistd.h>
  57
  58 #include "../../stdlib/FreeBSD/atexit.h"
  59 #include "../../stdtime/FreeBSD/tzfile.h"
  60
  61 #define _PATH_ZONEINFO  TZDIR   /* from tzfile.h */
  62
  63 /*
  64  * sysconf --
  65  *      get configurable system variables.
  66  *
  67  * XXX
  68  * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values
  69  * not change during the lifetime of the calling process.  This would seem
  70  * to require that any change to system limits kill all running processes.
  71  * A workaround might be to cache the values when they are first retrieved
  72  * and then simply return the cached value on subsequent calls.  This is
  73  * less useful than returning up-to-date values, however.
  74  */
  75 long
  76 sysconf(name)
  77         int name;
  78 {
  79         struct rlimit rl;
  80         quad_t qdvalue; /* for kern.sysv.shmmin */
  81         size_t len;
  82         int mib[3], sverrno, value;
  83         long defaultresult;
  84         const char *path;
  85
  86         len = sizeof(value);
  87         defaultresult = -1;
  88
  89         switch (name) {
  90         case _SC_ARG_MAX:
  91                 mib[0] = CTL_KERN;
  92                 mib[1] = KERN_ARGMAX;
  93                 break;
  94         case _SC_CHILD_MAX:
  95                 if (getrlimit(RLIMIT_NPROC, &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_CLK_TCK:
 105                 return (CLK_TCK);
 106         case _SC_NGROUPS_MAX:
 107                 mib[0] = CTL_KERN;
 108                 mib[1] = KERN_NGROUPS;
 109                 break;
 110         case _SC_OPEN_MAX:
 111         case _SC_STREAM_MAX:    /* assume fds run out before memory does */
 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                 return ((long)rl.rlim_cur);
 121         case _SC_JOB_CONTROL:
 122                 return (_POSIX_JOB_CONTROL);
 123         case _SC_SAVED_IDS:
 124                 /* XXX - must be 1 */
 125                 mib[0] = CTL_KERN;
 126                 mib[1] = KERN_SAVED_IDS;
 127                 goto yesno;
 128         case _SC_VERSION:
 129                 mib[0] = CTL_KERN;
 130                 mib[1] = KERN_POSIX1;
 131                 break;
 132         case _SC_BC_BASE_MAX:
 133                 return (BC_BASE_MAX);
 134         case _SC_BC_DIM_MAX:
 135                 return (BC_DIM_MAX);
 136         case _SC_BC_SCALE_MAX:
 137                 return (BC_SCALE_MAX);
 138         case _SC_BC_STRING_MAX:
 139                 return (BC_STRING_MAX);
 140         case _SC_COLL_WEIGHTS_MAX:
 141                 return (COLL_WEIGHTS_MAX);
 142         case _SC_EXPR_NEST_MAX:
 143                 return (EXPR_NEST_MAX);
 144         case _SC_LINE_MAX:
 145                 return (LINE_MAX);
 146         case _SC_RE_DUP_MAX:
 147                 return (RE_DUP_MAX);
 148         case _SC_2_VERSION:
 149                 /*
 150                  * This is something of a lie, but it would be silly at
 151                  * this point to try to deduce this from the contents
 152                  * of the filesystem.
 153                  */
 154                 return (_POSIX2_VERSION);
 155         case _SC_2_C_BIND:
 156                 return (_POSIX2_C_BIND);
 157         case _SC_2_C_DEV:
 158                 return (_POSIX2_C_DEV);
 159         case _SC_2_CHAR_TERM:
 160                 return (_POSIX2_CHAR_TERM);
 161         case _SC_2_FORT_DEV:
 162                 return (_POSIX2_FORT_DEV);
 163         case _SC_2_FORT_RUN:
 164                 return (_POSIX2_FORT_RUN);
 165         case _SC_2_LOCALEDEF:
 166                 return (_POSIX2_LOCALEDEF);
 167         case _SC_2_SW_DEV:
 168                 return (_POSIX2_SW_DEV);
 169         case _SC_2_UPE:
 170                 return (_POSIX2_UPE);
 171         case _SC_TZNAME_MAX:
 172                 path = _PATH_ZONEINFO;
 173 do_NAME_MAX:
 174                 sverrno = errno;
 175                 errno = 0;
 176                 value = pathconf(path, _PC_NAME_MAX);
 177                 if (value == -1 && errno != 0)
 178                         return (-1);
 179                 errno = sverrno;
 180                 return (value);
 181
 182         case _SC_ASYNCHRONOUS_IO:
 183 #if _POSIX_ASYNCHRONOUS_IO == 0
 184                 mib[0] = CTL_P1003_1B;
 185                 mib[1] = CTL_P1003_1B_ASYNCHRONOUS_IO;
 186                 break;
 187 #else
 188                 return (_POSIX_ASYNCHRONOUS_IO);
 189 #endif
 190         case _SC_MAPPED_FILES:
 191                 return (_POSIX_MAPPED_FILES);
 192         case _SC_MEMLOCK:
 193                 return (_POSIX_MEMLOCK);
 194         case _SC_MEMLOCK_RANGE:
 195                 return (_POSIX_MEMLOCK_RANGE);
 196         case _SC_MEMORY_PROTECTION:
 197                 return (_POSIX_MEMORY_PROTECTION);
 198         case _SC_MESSAGE_PASSING:
 199 #if _POSIX_MESSAGE_PASSING == 0
 200                 mib[0] = CTL_P1003_1B;
 201                 mib[1] = CTL_P1003_1B_MESSAGE_PASSING;
 202                 goto yesno;
 203 #else
 204                 return (_POSIX_MESSAGE_PASSING);
 205 #endif
 206         case _SC_PRIORITIZED_IO:
 207 #if _POSIX_PRIORITIZED_IO == 0
 208                 mib[0] = CTL_P1003_1B;
 209                 mib[1] = CTL_P1003_1B_PRIORITIZED_IO;
 210                 goto yesno;
 211 #else
 212                 return (_POSIX_PRIORITIZED_IO);
 213 #endif
 214         case _SC_PRIORITY_SCHEDULING:
 215 #if _POSIX_PRIORITY_SCHEDULING == 0
 216                 mib[0] = CTL_P1003_1B;
 217                 mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING;
 218                 goto yesno;
 219 #else
 220                 return (_POSIX_PRIORITY_SCHEDULING);
 221 #endif
 222         case _SC_REALTIME_SIGNALS:
 223 #if _POSIX_REALTIME_SIGNALS == 0
 224                 mib[0] = CTL_P1003_1B;
 225                 mib[1] = CTL_P1003_1B_REALTIME_SIGNALS;
 226                 goto yesno;
 227 #else
 228                 return (_POSIX_REALTIME_SIGNALS);
 229 #endif
 230         case _SC_SEMAPHORES:
 231 #if _POSIX_SEMAPHORES == 0
 232                 mib[0] = CTL_P1003_1B;
 233                 mib[1] = CTL_P1003_1B_SEMAPHORES;
 234                 goto yesno;
 235 #else
 236                 return (_POSIX_SEMAPHORES);
 237 #endif
 238         case _SC_FSYNC:
 239                 return (_POSIX_FSYNC);
 240
 241         case _SC_SHARED_MEMORY_OBJECTS:
 242                 return (_POSIX_SHARED_MEMORY_OBJECTS);
 243         case _SC_SYNCHRONIZED_IO:
 244 #if _POSIX_SYNCHRONIZED_IO == 0
 245                 mib[0] = CTL_P1003_1B;
 246                 mib[1] = CTL_P1003_1B_SYNCHRONIZED_IO;
 247                 goto yesno;
 248 #else
 249                 return (_POSIX_SYNCHRONIZED_IO);
 250 #endif
 251         case _SC_TIMERS:
 252 #if _POSIX_TIMERS == 0
 253                 mib[0] = CTL_P1003_1B;
 254                 mib[1] = CTL_P1003_1B_TIMERS;
 255                 goto yesno;
 256 #else
 257                 return (_POSIX_TIMERS);
 258 #endif
 259         case _SC_AIO_LISTIO_MAX:
 260         case _SC_AIO_MAX:
 261                 mib[0] = CTL_KERN;;
 262                 mib[1] = KERN_AIOMAX;
 263                 break;
 264
 265         case _SC_AIO_PRIO_DELTA_MAX:
 266 #if defined(CTL_P1003_1B) && defined(CTL_P1003_1B_AIO_PRIO_DELTA_MAX)
 267                 mib[0] = CTL_P1003_1B;
 268                 mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX;
 269                 break;
 270 #else
 271                 return (-1);
 272 #endif
 273         case _SC_DELAYTIMER_MAX:
 274 #if defined(CTL_P1003_1B) && defined(CTL_P1003_1B_DELAYTIMER_MAX)
 275                 mib[0] = CTL_P1003_1B;
 276                 mib[1] = CTL_P1003_1B_DELAYTIMER_MAX;
 277                 goto yesno;
 278 #else
 279                 return (-1);
 280 #endif
 281         case _SC_MQ_OPEN_MAX:
 282 #if defined(CTL_P1003_1B) && defined(CTL_P1003_1B_MQ_OPEN_MAX)
 283                 mib[0] = CTL_P1003_1B;
 284                 mib[1] = CTL_P1003_1B_MQ_OPEN_MAX;
 285                 goto yesno;
 286 #else
 287                 return (-1);
 288 #endif
 289         case _SC_PAGESIZE:
 290                 defaultresult = getpagesize();
 291 #if defined(CTL_P1003_1B) && defined(CTL_P1003_1B_PAGESIZE)
 292                 mib[0] = CTL_P1003_1B;
 293                 mib[1] = CTL_P1003_1B_PAGESIZE;
 294                 goto yesno;
 295 #else
 296                 return defaultresult;
 297 #endif
 298         case _SC_RTSIG_MAX:
 299 #if defined(CTL_P1003_1B) && defined(CTL_P1003_1B_RTSIG_MAX)
 300                 mib[0] = CTL_P1003_1B;
 301                 mib[1] = CTL_P1003_1B_RTSIG_MAX;
 302                 goto yesno;
 303 #else
 304                 return (-1);
 305 #endif
 306         case _SC_SEM_NSEMS_MAX:
 307                 return (sysctlbyname("kern.sysv.semmns", &value, &len, NULL, 0) == -1 ? -1 : value);
 308
 309         case _SC_SEM_VALUE_MAX:
 310 #if SEM_VALUE_MAX == 0
 311                 mib[0] = CTL_P1003_1B;
 312                 mib[1] = CTL_P1003_1B_SEM_VALUE_MAX;
 313                 goto yesno;
 314 #else
 315                 return (SEM_VALUE_MAX);
 316 #endif
 317         case _SC_SIGQUEUE_MAX:
 318 #if defined(CTL_P1003_1B) && defined(CTL_P1003_1B_SIGQUEUE_MAX)
 319                 mib[0] = CTL_P1003_1B;
 320                 mib[1] = CTL_P1003_1B_SIGQUEUE_MAX;
 321                 goto yesno;
 322 #else
 323                 return (-1);
 324 #endif
 325         case _SC_TIMER_MAX:
 326 #if defined(CTL_P1003_1B) && defined(CTL_P1003_1B_TIMER_MAX)
 327                 mib[0] = CTL_P1003_1B;
 328                 mib[1] = CTL_P1003_1B_TIMER_MAX;
 329 #else
 330                 return (-1);
 331 #endif
 332
 333 yesno:          if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
 334                         return (-1);
 335                 if (value == 0)
 336                         return (defaultresult);
 337                 return (value);
 338         case _SC_2_PBS:
 339         case _SC_2_PBS_ACCOUNTING:
 340         case _SC_2_PBS_CHECKPOINT:
 341         case _SC_2_PBS_LOCATE:
 342         case _SC_2_PBS_MESSAGE:
 343         case _SC_2_PBS_TRACK:
 344                 return -1;
 345         case _SC_ADVISORY_INFO:
 346 #if _POSIX_ADVISORY_INFO == 0
 347 #error "_POSIX_ADVISORY_INFO"
 348 #else
 349                 return (_POSIX_ADVISORY_INFO);
 350 #endif
 351         case _SC_BARRIERS:
 352 #if _POSIX_BARRIERS == 0
 353 #error "_POSIX_BARRIERS"
 354 #else
 355                 return (_POSIX_BARRIERS);
 356 #endif
 357         case _SC_CLOCK_SELECTION:
 358 #if _POSIX_CLOCK_SELECTION == 0
 359 #error "_POSIX_CLOCK_SELECTION"
 360 #else
 361                 return (_POSIX_CLOCK_SELECTION);
 362 #endif
 363         case _SC_CPUTIME:
 364 #if _POSIX_CPUTIME == 0
 365 #error "_POSIX_CPUTIME"
 366 #else
 367                 return (_POSIX_CPUTIME);
 368 #endif
 369         case _SC_FILE_LOCKING:
 370         case _SC_GETGR_R_SIZE_MAX:
 371 /*              return sizeof(group) + group_name_max + group_passwd_max + max_group_member*(MAXLOGNAME+1); */
 372                 return 4096;    /* INT_MAX is too big for Perl */
 373         case _SC_GETPW_R_SIZE_MAX:
 374                 return 4096;
 375         case _SC_HOST_NAME_MAX:
 376                 return (MAXHOSTNAMELEN - 1); /* does not include \0 */
 377         case _SC_LOGIN_NAME_MAX:
 378                 return (MAXLOGNAME);
 379         case _SC_MONOTONIC_CLOCK:
 380 #if _POSIX_MONOTONIC_CLOCK == 0
 381 #error "_POSIX_MONOTONIC_CLOCK"
 382 #else
 383                 return (_POSIX_MONOTONIC_CLOCK);
 384 #endif
 385         case _SC_MQ_PRIO_MAX:
 386                 return (-1);
 387         case _SC_READER_WRITER_LOCKS:
 388                 return (_POSIX_READER_WRITER_LOCKS);
 389         case _SC_REGEXP:
 390                 return (_POSIX_REGEXP);
 391         case _SC_SHELL:
 392                 return (_POSIX_SHELL);
 393         case _SC_SPAWN:
 394                 return (_POSIX_SPAWN);
 395         case _SC_SPIN_LOCKS:
 396                 return (_POSIX_SPIN_LOCKS);
 397         case _SC_SPORADIC_SERVER:
 398 #if _POSIX_SPORADIC_SERVER == 0
 399 #error "_POSIX_SPORADIC_SERVER"
 400 #else
 401                 return (_POSIX_SPORADIC_SERVER);
 402 #endif
 403         case _SC_THREAD_ATTR_STACKADDR:
 404                 return (_POSIX_THREAD_ATTR_STACKADDR);
 405         case _SC_THREAD_ATTR_STACKSIZE:
 406                 return (_POSIX_THREAD_ATTR_STACKSIZE);
 407         case _SC_THREAD_CPUTIME:
 408                 return (_POSIX_THREAD_CPUTIME);
 409         case _SC_THREAD_DESTRUCTOR_ITERATIONS:
 410                 return (PTHREAD_DESTRUCTOR_ITERATIONS);
 411         case _SC_THREAD_KEYS_MAX:
 412                 return (PTHREAD_KEYS_MAX);
 413         case _SC_THREAD_PRIO_INHERIT:
 414                 return (_POSIX_THREAD_PRIO_INHERIT);
 415         case _SC_THREAD_PRIO_PROTECT:
 416                 return (_POSIX_THREAD_PRIO_PROTECT);
 417         case _SC_THREAD_PRIORITY_SCHEDULING:
 418                 return (_POSIX_THREAD_PRIORITY_SCHEDULING);
 419         case _SC_THREAD_PROCESS_SHARED:
 420                 return (_POSIX_THREAD_PROCESS_SHARED);
 421         case _SC_THREAD_SAFE_FUNCTIONS:
 422                 return (_POSIX_THREAD_SAFE_FUNCTIONS);
 423         case _SC_THREAD_SPORADIC_SERVER:
 424                 return (_POSIX_THREAD_SPORADIC_SERVER);
 425         case _SC_THREAD_STACK_MIN:
 426                 return (PTHREAD_STACK_MIN);
 427         case _SC_THREAD_THREADS_MAX:
 428 #ifdef PTHREAD_THREADS_MAX
 429                 return (PTHREAD_THREADS_MAX); /* XXX wrong type! */
 430 #else
 431                 return (-1);
 432 #endif
 433         case _SC_TIMEOUTS:
 434                 return (_POSIX_TIMEOUTS);
 435         case _SC_THREADS:
 436                 return (_POSIX_THREADS);
 437         case _SC_TRACE:
 438 #if _POSIX_TRACE == 0
 439 #error "_POSIX_TRACE"
 440                 /* While you're implementing this, also do the ones below. */
 441 #else
 442                 return (_POSIX_TRACE);
 443 #endif
 444         case _SC_TRACE_EVENT_FILTER:
 445                 return (_POSIX_TRACE_EVENT_FILTER);
 446         case _SC_TRACE_INHERIT:
 447                 return (_POSIX_TRACE_INHERIT);
 448         case _SC_TRACE_LOG:
 449                 return (_POSIX_TRACE_LOG);
 450         case _SC_TTY_NAME_MAX:
 451                 path = "/"; // should be _PATH_DEV (PR-3624562)
 452                 goto do_NAME_MAX;
 453         case _SC_TYPED_MEMORY_OBJECTS:
 454 #if _POSIX_TYPED_MEMORY_OBJECTS == 0
 455 #error "_POSIX_TYPED_MEMORY_OBJECTS"
 456 #else
 457                 return (_POSIX_TYPED_MEMORY_OBJECTS);
 458 #endif
 459         case _SC_V6_ILP32_OFF32:
 460 #if _V6_ILP32_OFF32 == 0
 461                 if (sizeof(int) * CHAR_BIT == 32 &&
 462                     sizeof(int) == sizeof(long) &&
 463                     sizeof(long) == sizeof(void *) &&
 464                     sizeof(void *) == sizeof(off_t))
 465                         return 1;
 466                 else
 467                         return -1;
 468 #else
 469                 return (_V6_ILP32_OFF32);
 470 #endif
 471         case _SC_V6_ILP32_OFFBIG:
 472 #if _V6_ILP32_OFFBIG == 0
 473                 if (sizeof(int) * CHAR_BIT == 32 &&
 474                     sizeof(int) == sizeof(long) &&
 475                     sizeof(long) == sizeof(void *) &&
 476                     sizeof(off_t) * CHAR_BIT >= 64)
 477                         return 1;
 478                 else
 479                         return -1;
 480 #else
 481                 return (_V6_ILP32_OFFBIG);
 482 #endif
 483         case _SC_V6_LP64_OFF64:
 484 #if _V6_LP64_OFF64 == 0
 485                 if (sizeof(int) * CHAR_BIT == 32 &&
 486                     sizeof(long) * CHAR_BIT == 64 &&
 487                     sizeof(long) == sizeof(void *) &&
 488                     sizeof(void *) == sizeof(off_t))
 489                         return 1;
 490                 else
 491                         return -1;
 492 #else
 493                 return (_V6_LP64_OFF64);
 494 #endif
 495         case _SC_V6_LPBIG_OFFBIG:
 496 #if _V6_LPBIG_OFFBIG == 0
 497                 if (sizeof(int) * CHAR_BIT >= 32 &&
 498                     sizeof(long) * CHAR_BIT >= 64 &&
 499                     sizeof(void *) * CHAR_BIT >= 64 &&
 500                     sizeof(off_t) * CHAR_BIT >= 64)
 501                         return 1;
 502                 else
 503                         return -1;
 504 #else
 505                 return (_V6_LPBIG_OFFBIG);
 506 #endif
 507         case _SC_ATEXIT_MAX:
 508                 return (INT_MAX);       /* unlimited */
 509         case _SC_IOV_MAX:
 510 #ifdef KERN_IOV_MAX
 511                 mib[0] = CTL_KERN;
 512                 mib[1] = KERN_IOV_MAX;
 513                 break;
 514 #else
 515                 return (IOV_MAX);
 516 #endif
 517         case _SC_XOPEN_CRYPT:
 518                 return (_XOPEN_CRYPT);
 519         case _SC_XOPEN_ENH_I18N:
 520                 return (_XOPEN_ENH_I18N);
 521         case _SC_XOPEN_LEGACY:
 522                 return (_XOPEN_LEGACY);
 523         case _SC_XOPEN_REALTIME:
 524 #if _XOPEN_REALTIME == 0
 525                 sverrno = errno;
 526                 value = sysconf(_SC_ASYNCHRONOUS_IO) > 0 &&
 527                         sysconf(_SC_MEMLOCK) > 0 &&
 528                         sysconf(_SC_MEMLOCK_RANGE) > 0 &&
 529                         sysconf(_SC_MESSAGE_PASSING) > 0 &&
 530                         sysconf(_SC_PRIORITY_SCHEDULING) > 0 &&
 531                         sysconf(_SC_REALTIME_SIGNALS) > 0 &&
 532                         sysconf(_SC_SEMAPHORES) > 0 &&
 533                         sysconf(_SC_SHARED_MEMORY_OBJECTS) > 0 &&
 534                         sysconf(_SC_SYNCHRONIZED_IO) > 0 &&
 535                         sysconf(_SC_TIMERS) > 0;
 536                 errno = sverrno;
 537                 if (value)
 538                         return (200112L);
 539                 else
 540                         return (-1);
 541 #else
 542                 return (_XOPEN_REALTIME);
 543 #endif
 544         case _SC_XOPEN_REALTIME_THREADS:
 545 #if _XOPEN_REALTIME_THREADS == 0
 546 #error "_XOPEN_REALTIME_THREADS"
 547 #else
 548                 return (_XOPEN_REALTIME_THREADS);
 549 #endif
 550         case _SC_XOPEN_SHM:
 551                 sverrno = errno;
 552                 len = sizeof(qdvalue);
 553                 if (sysctlbyname("kern.sysv.shmmin", &qdvalue, &len, NULL,
 554                     0) == -1) {
 555                         errno = sverrno;
 556                         return (-1);
 557                 }
 558                 errno = sverrno;
 559                 return (1);
 560         case _SC_XOPEN_STREAMS:
 561                 return (_XOPEN_STREAMS);
 562         case _SC_XOPEN_UNIX:
 563                 return (_XOPEN_UNIX);
 564 #ifdef _XOPEN_VERSION
 565         case _SC_XOPEN_VERSION:
 566                 return (_XOPEN_VERSION);
 567 #endif
 568 #ifdef _XOPEN_XCU_VERSION
 569         case _SC_XOPEN_XCU_VERSION:
 570                 return (_XOPEN_XCU_VERSION);
 571 #endif
 572         case _SC_SYMLOOP_MAX:
 573                 return (MAXSYMLINKS);
 574         case _SC_RAW_SOCKETS:
 575                 return (_POSIX_RAW_SOCKETS);
 576         case _SC_IPV6:
 577 #if _POSIX_IPV6 == 0
 578                 sverrno = errno;
 579                 value = socket(PF_INET6, SOCK_DGRAM, 0);
 580                 errno = sverrno;
 581                 if (value >= 0) {
 582                         close(value);
 583                         return (200112L);
 584                 } else
 585                         return (0);
 586 #else
 587                 return (_POSIX_IPV6);
 588 #endif
 589
 590 #ifdef _SC_NPROCESSORS_CONF
 591         case _SC_NPROCESSORS_CONF:
 592 #endif
 593 #ifdef _SC_NPROCESSORS_ONLN
 594         case _SC_NPROCESSORS_ONLN:
 595 #endif
 596 #if defined(_SC_NPROCESSORS_CONF) || defined(_SC_NPROCESSORS_ONLN)
 597                 mib[0] = CTL_HW;
 598                 mib[1] = HW_NCPU;
 599                 break;
 600 #endif
 601         case _SC_XBS5_ILP32_OFF32:
 602                 return (_XBS5_ILP32_OFF32);
 603         case _SC_XBS5_ILP32_OFFBIG:
 604                 return (_XBS5_ILP32_OFFBIG);
 605         case _SC_XBS5_LP64_OFF64:
 606                 return (_XBS5_LP64_OFF64);
 607         case _SC_XBS5_LPBIG_OFFBIG:
 608                 return (_XBS5_LPBIG_OFFBIG);
 609         case _SC_SS_REPL_MAX:
 610                 return (_POSIX_SS_REPL_MAX);
 611         case _SC_TRACE_EVENT_NAME_MAX:
 612                 return (_POSIX_TRACE_EVENT_NAME_MAX);
 613         case _SC_TRACE_NAME_MAX:
 614                 return (_POSIX_TRACE_NAME_MAX);
 615         case _SC_TRACE_SYS_MAX:
 616                 return (_POSIX_TRACE_SYS_MAX);
 617         case _SC_TRACE_USER_EVENT_MAX:
 618                 return (_POSIX_TRACE_USER_EVENT_MAX);
 619         case _SC_PASS_MAX:
 620                 return (PASS_MAX);
 621
 622         default:
 623                 errno = EINVAL;
 624                 return (-1);
 625         }
 626         return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value);
 627 }