sysdeps/posix/sysconf.c

   1 /* Copyright (C) 1991-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <limits.h>
  20 #include <grp.h>
  21 #include <pwd.h>
  22 #include <stddef.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <time.h>
  27 #include <unistd.h>
  28 #include <sys/param.h>
  29 #include <sys/stat.h>
  30 #include <sys/sysinfo.h>
  31 #include <sys/types.h>
  32 #include <regex.h>
  33
  34 #define NEED_SPEC_ARRAY 0
  35 #include <posix-conf-vars.h>
  36
  37 #define NEED_CHECK_SPEC \
  38   (!defined _XBS5_ILP32_OFF32 || !defined _XBS5_ILP32_OFFBIG \
  39    || !defined _XBS5_LP64_OFF64 || !defined _XBS5_LPBIG_OFFBIG \
  40    || !defined _POSIX_V6_ILP32_OFF32 || !defined _POSIX_V6_ILP32_OFFBIG \
  41    || !defined _POSIX_V6_LP64_OFF64 || !defined _POSIX_V6_LPBIG_OFFBIG \
  42    || !defined _POSIX_V7_ILP32_OFF32 || !defined _POSIX_V7_ILP32_OFFBIG \
  43    || !defined _POSIX_V7_LP64_OFF64 || !defined _POSIX_V7_LPBIG_OFFBIG)
  44 #if NEED_CHECK_SPEC
  45 static long int __sysconf_check_spec (const char *spec);
  46 #endif
  47
  48
  49 /* Get the value of the system variable NAME.  */
  50 long int
  51 __sysconf (name)
  52      int name;
  53 {
  54   switch (name)
  55     {
  56       /* Also add obsolete or unnecessarily added constants here.  */
  57     case _SC_EQUIV_CLASS_MAX:
  58     default:
  59       __set_errno (EINVAL);
  60       return -1;
  61
  62     case _SC_ARG_MAX:
  63 #ifdef  ARG_MAX
  64       return ARG_MAX;
  65 #else
  66       return -1;
  67 #endif
  68
  69     case _SC_CHILD_MAX:
  70 #ifdef  CHILD_MAX
  71       return CHILD_MAX;
  72 #else
  73       return __get_child_max ();
  74 #endif
  75
  76     case _SC_CLK_TCK:
  77       return __getclktck ();
  78
  79     case _SC_NGROUPS_MAX:
  80 #ifdef  NGROUPS_MAX
  81       return NGROUPS_MAX;
  82 #else
  83       return -1;
  84 #endif
  85
  86     case _SC_OPEN_MAX:
  87       return __getdtablesize ();
  88
  89     case _SC_STREAM_MAX:
  90 #ifdef  STREAM_MAX
  91       return STREAM_MAX;
  92 #else
  93       return FOPEN_MAX;
  94 #endif
  95
  96     case _SC_TZNAME_MAX:
  97       return MAX (__tzname_max (), _POSIX_TZNAME_MAX);
  98
  99     case _SC_JOB_CONTROL:
 100 #if CONF_IS_DEFINED_SET (_POSIX_JOB_CONTROL)
 101       return _POSIX_JOB_CONTROL;
 102 #else
 103       return -1;
 104 #endif
 105
 106     case _SC_SAVED_IDS:
 107 #if CONF_IS_DEFINED_SET (_POSIX_SAVED_IDS)
 108       return 1;
 109 #else
 110       return -1;
 111 #endif
 112
 113     case _SC_REALTIME_SIGNALS:
 114 #if CONF_IS_DEFINED_SET (_POSIX_REALTIME_SIGNALS)
 115       return _POSIX_REALTIME_SIGNALS;
 116 #else
 117       return -1;
 118 #endif
 119
 120     case _SC_PRIORITY_SCHEDULING:
 121 #if CONF_IS_DEFINED_SET (_POSIX_PRIORITY_SCHEDULING)
 122       return _POSIX_PRIORITY_SCHEDULING;
 123 #else
 124       return -1;
 125 #endif
 126
 127     case _SC_TIMERS:
 128 #if CONF_IS_DEFINED_SET (_POSIX_TIMERS)
 129       return _POSIX_TIMERS;
 130 #else
 131       return -1;
 132 #endif
 133
 134     case _SC_ASYNCHRONOUS_IO:
 135 #if CONF_IS_DEFINED_SET (_POSIX_ASYNCHRONOUS_IO)
 136       return _POSIX_ASYNCHRONOUS_IO;
 137 #else
 138       return -1;
 139 #endif
 140
 141     case _SC_PRIORITIZED_IO:
 142 #if CONF_IS_DEFINED_SET (_POSIX_PRIORITIZED_IO)
 143       return _POSIX_PRIORITIZED_IO;
 144 #else
 145       return -1;
 146 #endif
 147
 148     case _SC_SYNCHRONIZED_IO:
 149 #if CONF_IS_DEFINED_SET (_POSIX_SYNCHRONIZED_IO)
 150       return _POSIX_SYNCHRONIZED_IO;
 151 #else
 152       return -1;
 153 #endif
 154
 155     case _SC_FSYNC:
 156 #if CONF_IS_DEFINED_SET (_POSIX_FSYNC)
 157       return _POSIX_FSYNC;
 158 #else
 159       return -1;
 160 #endif
 161
 162     case _SC_MAPPED_FILES:
 163 #if CONF_IS_DEFINED_SET (_POSIX_MAPPED_FILES)
 164       return _POSIX_MAPPED_FILES;
 165 #else
 166       return -1;
 167 #endif
 168
 169     case _SC_MEMLOCK:
 170 #if CONF_IS_DEFINED_SET (_POSIX_MEMLOCK)
 171       return _POSIX_MEMLOCK;
 172 #else
 173       return -1;
 174 #endif
 175
 176     case _SC_MEMLOCK_RANGE:
 177 #if CONF_IS_DEFINED_SET (_POSIX_MEMLOCK_RANGE)
 178       return _POSIX_MEMLOCK_RANGE;
 179 #else
 180       return -1;
 181 #endif
 182
 183     case _SC_MEMORY_PROTECTION:
 184 #if CONF_IS_DEFINED_SET (_POSIX_MEMORY_PROTECTION)
 185       return _POSIX_MEMORY_PROTECTION;
 186 #else
 187       return -1;
 188 #endif
 189
 190     case _SC_MESSAGE_PASSING:
 191 #if CONF_IS_DEFINED_SET (_POSIX_MESSAGE_PASSING)
 192       return _POSIX_MESSAGE_PASSING;
 193 #else
 194       return -1;
 195 #endif
 196
 197     case _SC_SEMAPHORES:
 198 #if CONF_IS_DEFINED_SET (_POSIX_SEMAPHORES)
 199       return _POSIX_SEMAPHORES;
 200 #else
 201       return -1;
 202 #endif
 203
 204     case _SC_SHARED_MEMORY_OBJECTS:
 205 #if CONF_IS_DEFINED_SET (_POSIX_SHARED_MEMORY_OBJECTS)
 206       return _POSIX_SHARED_MEMORY_OBJECTS;
 207 #else
 208       return -1;
 209 #endif
 210
 211     case _SC_VERSION:
 212       return _POSIX_VERSION;
 213
 214     case _SC_PAGESIZE:
 215       return __getpagesize ();
 216
 217     case _SC_AIO_LISTIO_MAX:
 218 #ifdef  AIO_LISTIO_MAX
 219       return AIO_LISTIO_MAX;
 220 #else
 221       return -1;
 222 #endif
 223
 224     case _SC_AIO_MAX:
 225 #ifdef  AIO_MAX
 226       return AIO_MAX;
 227 #else
 228       return -1;
 229 #endif
 230
 231     case _SC_AIO_PRIO_DELTA_MAX:
 232 #ifdef  AIO_PRIO_DELTA_MAX
 233       return AIO_PRIO_DELTA_MAX;
 234 #else
 235       return -1;
 236 #endif
 237
 238     case _SC_DELAYTIMER_MAX:
 239 #ifdef  DELAYTIMER_MAX
 240       return DELAYTIMER_MAX;
 241 #else
 242       return -1;
 243 #endif
 244
 245     case _SC_MQ_OPEN_MAX:
 246 #ifdef  MQ_OPEN_MAX
 247       return MQ_OPEN_MAX;
 248 #else
 249       return -1;
 250 #endif
 251
 252     case _SC_MQ_PRIO_MAX:
 253 #ifdef  MQ_PRIO_MAX
 254       return MQ_PRIO_MAX;
 255 #else
 256       return -1;
 257 #endif
 258
 259     case _SC_RTSIG_MAX:
 260 #ifdef  RTSIG_MAX
 261       return RTSIG_MAX;
 262 #else
 263       return -1;
 264 #endif
 265
 266     case _SC_SEM_NSEMS_MAX:
 267 #ifdef  SEM_NSEMS_MAX
 268       return SEM_NSEMS_MAX;
 269 #else
 270       return -1;
 271 #endif
 272
 273     case _SC_SEM_VALUE_MAX:
 274 #ifdef  SEM_VALUE_MAX
 275       return SEM_VALUE_MAX;
 276 #else
 277       return -1;
 278 #endif
 279
 280     case _SC_SIGQUEUE_MAX:
 281 #ifdef  SIGQUEUE_MAX
 282       return SIGQUEUE_MAX;
 283 #else
 284       return -1;
 285 #endif
 286
 287     case _SC_TIMER_MAX:
 288 #ifdef  TIMER_MAX
 289       return TIMER_MAX;
 290 #else
 291       return -1;
 292 #endif
 293
 294     case _SC_BC_BASE_MAX:
 295 #ifdef  BC_BASE_MAX
 296       return BC_BASE_MAX;
 297 #else
 298       return -1;
 299 #endif
 300
 301     case _SC_BC_DIM_MAX:
 302 #ifdef  BC_DIM_MAX
 303       return BC_DIM_MAX;
 304 #else
 305       return -1;
 306 #endif
 307
 308     case _SC_BC_SCALE_MAX:
 309 #ifdef  BC_SCALE_MAX
 310       return BC_SCALE_MAX;
 311 #else
 312       return -1;
 313 #endif
 314
 315     case _SC_BC_STRING_MAX:
 316 #ifdef  BC_STRING_MAX
 317       return BC_STRING_MAX;
 318 #else
 319       return -1;
 320 #endif
 321
 322     case _SC_COLL_WEIGHTS_MAX:
 323 #ifdef  COLL_WEIGHTS_MAX
 324       return COLL_WEIGHTS_MAX;
 325 #else
 326       return -1;
 327 #endif
 328
 329     case _SC_EXPR_NEST_MAX:
 330 #ifdef  EXPR_NEST_MAX
 331       return EXPR_NEST_MAX;
 332 #else
 333       return -1;
 334 #endif
 335
 336     case _SC_LINE_MAX:
 337 #ifdef  LINE_MAX
 338       return LINE_MAX;
 339 #else
 340       return -1;
 341 #endif
 342
 343     case _SC_RE_DUP_MAX:
 344 #ifdef  RE_DUP_MAX
 345       return RE_DUP_MAX;
 346 #else
 347       return -1;
 348 #endif
 349
 350     case _SC_CHARCLASS_NAME_MAX:
 351 #ifdef  CHARCLASS_NAME_MAX
 352       return CHARCLASS_NAME_MAX;
 353 #else
 354       return -1;
 355 #endif
 356
 357     case _SC_PII:
 358 #if CONF_IS_DEFINED_SET (_POSIX_PII)
 359       return 1;
 360 #else
 361       return -1;
 362 #endif
 363
 364     case _SC_PII_XTI:
 365 #if CONF_IS_DEFINED_SET (_POSIX_PII_XTI)
 366       return 1;
 367 #else
 368       return -1;
 369 #endif
 370
 371     case _SC_PII_SOCKET:
 372 #if CONF_IS_DEFINED_SET (_POSIX_PII_SOCKET)
 373       return 1;
 374 #else
 375       return -1;
 376 #endif
 377
 378     case _SC_PII_INTERNET:
 379 #if CONF_IS_DEFINED_SET (_POSIX_PII_INTERNET)
 380       return 1;
 381 #else
 382       return -1;
 383 #endif
 384
 385     case _SC_PII_OSI:
 386 #if CONF_IS_DEFINED_SET (_POSIX_PII_OSI)
 387       return 1;
 388 #else
 389       return -1;
 390 #endif
 391
 392     case _SC_POLL:
 393 #if CONF_IS_DEFINED_SET (_POSIX_POLL)
 394       return 1;
 395 #else
 396       return -1;
 397 #endif
 398
 399     case _SC_SELECT:
 400 #if CONF_IS_DEFINED_SET (_POSIX_SELECT)
 401       return 1;
 402 #else
 403       return -1;
 404 #endif
 405
 406       /* The same as _SC_IOV_MAX.  */
 407     case _SC_UIO_MAXIOV:
 408 #ifdef  UIO_MAXIOV
 409       return UIO_MAXIOV;
 410 #else
 411       return -1;
 412 #endif
 413
 414     case _SC_PII_INTERNET_STREAM:
 415 #if CONF_IS_DEFINED_SET (_POSIX_PII_INTERNET_STREAM)
 416       return 1;
 417 #else
 418       return -1;
 419 #endif
 420
 421     case _SC_PII_INTERNET_DGRAM:
 422 #if CONF_IS_DEFINED_SET (_POSIX_PII_INTERNET_DGRAM)
 423       return 1;
 424 #else
 425       return -1;
 426 #endif
 427
 428     case _SC_PII_OSI_COTS:
 429 #if CONF_IS_DEFINED_SET (_POSIX_PII_OSI_COTS)
 430       return 1;
 431 #else
 432       return -1;
 433 #endif
 434
 435     case _SC_PII_OSI_CLTS:
 436 #if CONF_IS_DEFINED_SET (_POSIX_PII_OSI_CLTS)
 437       return 1;
 438 #else
 439       return -1;
 440 #endif
 441
 442     case _SC_PII_OSI_M:
 443 #if CONF_IS_DEFINED_SET (_POSIX_PII_OSI_M)
 444       return 1;
 445 #else
 446       return -1;
 447 #endif
 448
 449     case _SC_T_IOV_MAX:
 450 #ifdef  _T_IOV_MAX
 451       return _T_IOV_MAX;
 452 #else
 453       return -1;
 454 #endif
 455
 456     case _SC_2_VERSION:
 457       return _POSIX2_VERSION;
 458
 459     case _SC_2_C_BIND:
 460 #ifdef  _POSIX2_C_BIND
 461       return _POSIX2_C_BIND;
 462 #else
 463       return -1;
 464 #endif
 465
 466     case _SC_2_C_DEV:
 467 #ifdef  _POSIX2_C_DEV
 468       return _POSIX2_C_DEV;
 469 #else
 470       return -1;
 471 #endif
 472
 473     case _SC_2_C_VERSION:
 474 #ifdef  _POSIX2_C_VERSION
 475       return _POSIX2_C_VERSION;
 476 #else
 477       return -1;
 478 #endif
 479
 480     case _SC_2_FORT_DEV:
 481 #ifdef  _POSIX2_FORT_DEV
 482       return _POSIX2_FORT_DEV;
 483 #else
 484       return -1;
 485 #endif
 486
 487     case _SC_2_FORT_RUN:
 488 #ifdef  _POSIX2_FORT_RUN
 489       return _POSIX2_FORT_RUN;
 490 #else
 491       return -1;
 492 #endif
 493
 494     case _SC_2_LOCALEDEF:
 495 #ifdef  _POSIX2_LOCALEDEF
 496       return _POSIX2_LOCALEDEF;
 497 #else
 498       return -1;
 499 #endif
 500
 501     case _SC_2_SW_DEV:
 502 #ifdef  _POSIX2_SW_DEV
 503       return _POSIX2_SW_DEV;
 504 #else
 505       return -1;
 506 #endif
 507
 508     case _SC_2_CHAR_TERM:
 509 #ifdef  _POSIX2_CHAR_TERM
 510       return _POSIX2_CHAR_TERM;
 511 #else
 512       return -1;
 513 #endif
 514
 515     case _SC_2_UPE:
 516 #ifdef  _POSIX2_UPE
 517       return _POSIX2_UPE;
 518 #else
 519       return -1;
 520 #endif
 521
 522       /* POSIX 1003.1c (POSIX Threads).  */
 523     case _SC_THREADS:
 524 #if CONF_IS_DEFINED_SET (_POSIX_THREADS)
 525       return _POSIX_THREADS;
 526 #else
 527       return -1;
 528 #endif
 529
 530     case _SC_THREAD_SAFE_FUNCTIONS:
 531 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_SAFE_FUNCTIONS)
 532       return _POSIX_THREAD_SAFE_FUNCTIONS;
 533 #else
 534       return -1;
 535 #endif
 536
 537     case _SC_GETGR_R_SIZE_MAX:
 538       return NSS_BUFLEN_GROUP;
 539
 540     case _SC_GETPW_R_SIZE_MAX:
 541       return NSS_BUFLEN_PASSWD;
 542
 543     case _SC_LOGIN_NAME_MAX:
 544 #ifdef  LOGIN_NAME_MAX
 545       return LOGIN_NAME_MAX;
 546 #else
 547       return -1;
 548 #endif
 549
 550     case _SC_TTY_NAME_MAX:
 551 #ifdef  TTY_NAME_MAX
 552       return TTY_NAME_MAX;
 553 #else
 554       return -1;
 555 #endif
 556
 557     case _SC_THREAD_DESTRUCTOR_ITERATIONS:
 558 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_DESTRUCTOR_ITERATIONS)
 559       return _POSIX_THREAD_DESTRUCTOR_ITERATIONS;
 560 #else
 561       return -1;
 562 #endif
 563
 564     case _SC_THREAD_KEYS_MAX:
 565 #ifdef  PTHREAD_KEYS_MAX
 566       return PTHREAD_KEYS_MAX;
 567 #else
 568       return -1;
 569 #endif
 570
 571     case _SC_THREAD_STACK_MIN:
 572 #ifdef  PTHREAD_STACK_MIN
 573       return PTHREAD_STACK_MIN;
 574 #else
 575       return -1;
 576 #endif
 577
 578     case _SC_THREAD_THREADS_MAX:
 579 #ifdef  PTHREAD_THREADS_MAX
 580       return PTHREAD_THREADS_MAX;
 581 #else
 582       return -1;
 583 #endif
 584
 585     case _SC_THREAD_ATTR_STACKADDR:
 586 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_ATTR_STACKADDR)
 587       return _POSIX_THREAD_ATTR_STACKADDR;
 588 #else
 589       return -1;
 590 #endif
 591
 592     case _SC_THREAD_ATTR_STACKSIZE:
 593 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_ATTR_STACKSIZE)
 594       return _POSIX_THREAD_ATTR_STACKSIZE;
 595 #else
 596       return -1;
 597 #endif
 598
 599     case _SC_THREAD_PRIORITY_SCHEDULING:
 600 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_PRIORITY_SCHEDULING)
 601       return _POSIX_THREAD_PRIORITY_SCHEDULING;
 602 #else
 603       return -1;
 604 #endif
 605
 606     case _SC_THREAD_PRIO_INHERIT:
 607 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_PRIO_INHERIT)
 608       return _POSIX_THREAD_PRIO_INHERIT;
 609 #else
 610       return -1;
 611 #endif
 612
 613     case _SC_THREAD_PRIO_PROTECT:
 614 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_PRIO_PROTECT)
 615       return _POSIX_THREAD_PRIO_PROTECT;
 616 #else
 617       return -1;
 618 #endif
 619
 620     case _SC_THREAD_PROCESS_SHARED:
 621 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_PROCESS_SHARED)
 622       return _POSIX_THREAD_PROCESS_SHARED;
 623 #else
 624       return -1;
 625 #endif
 626
 627     case _SC_NPROCESSORS_CONF:
 628       return __get_nprocs_conf ();
 629
 630     case _SC_NPROCESSORS_ONLN:
 631       return __get_nprocs ();
 632
 633     case _SC_PHYS_PAGES:
 634       return __get_phys_pages ();
 635
 636     case _SC_AVPHYS_PAGES:
 637       return __get_avphys_pages ();
 638
 639     case _SC_ATEXIT_MAX:
 640       /* We have no limit since we use lists.  */
 641       return INT_MAX;
 642
 643     case _SC_PASS_MAX:
 644       /* We have no limit but since the return value might be used to
 645          allocate a buffer we restrict the value.  */
 646       return BUFSIZ;
 647
 648     case _SC_XOPEN_VERSION:
 649       return _XOPEN_VERSION;
 650
 651     case _SC_XOPEN_XCU_VERSION:
 652       return _XOPEN_XCU_VERSION;
 653
 654     case _SC_XOPEN_UNIX:
 655       return _XOPEN_UNIX;
 656
 657     case _SC_XOPEN_CRYPT:
 658 #ifdef  _XOPEN_CRYPT
 659       return _XOPEN_CRYPT;
 660 #else
 661       return -1;
 662 #endif
 663
 664     case _SC_XOPEN_ENH_I18N:
 665 #ifdef  _XOPEN_ENH_I18N
 666       return _XOPEN_ENH_I18N;
 667 #else
 668       return -1;
 669 #endif
 670
 671     case _SC_XOPEN_SHM:
 672 #ifdef  _XOPEN_SHM
 673       return _XOPEN_SHM;
 674 #else
 675       return -1;
 676 #endif
 677
 678     case _SC_XOPEN_XPG2:
 679 #ifdef  _XOPEN_XPG2
 680       return _XOPEN_XPG2;
 681 #else
 682       return -1;
 683 #endif
 684
 685     case _SC_XOPEN_XPG3:
 686 #ifdef  _XOPEN_XPG3
 687       return _XOPEN_XPG3;
 688 #else
 689       return -1;
 690 #endif
 691
 692     case _SC_XOPEN_XPG4:
 693 #ifdef  _XOPEN_XPG4
 694       return _XOPEN_XPG4;
 695 #else
 696       return -1;
 697 #endif
 698
 699     case _SC_CHAR_BIT:
 700       return CHAR_BIT;
 701
 702     case _SC_CHAR_MAX:
 703       return CHAR_MAX;
 704
 705     case _SC_CHAR_MIN:
 706       return CHAR_MIN;
 707
 708     case _SC_INT_MAX:
 709       return INT_MAX;
 710
 711     case _SC_INT_MIN:
 712       return INT_MIN;
 713
 714     case _SC_LONG_BIT:
 715       return sizeof (long int) * CHAR_BIT;
 716
 717     case _SC_WORD_BIT:
 718       return sizeof (int) * CHAR_BIT;
 719
 720     case _SC_MB_LEN_MAX:
 721       return MB_LEN_MAX;
 722
 723     case _SC_NZERO:
 724       return NZERO;
 725
 726     case _SC_SSIZE_MAX:
 727       return _POSIX_SSIZE_MAX;
 728
 729     case _SC_SCHAR_MAX:
 730       return SCHAR_MAX;
 731
 732     case _SC_SCHAR_MIN:
 733       return SCHAR_MIN;
 734
 735     case _SC_SHRT_MAX:
 736       return SHRT_MAX;
 737
 738     case _SC_SHRT_MIN:
 739       return SHRT_MIN;
 740
 741     case _SC_UCHAR_MAX:
 742       return UCHAR_MAX;
 743
 744     case _SC_UINT_MAX:
 745       return UINT_MAX;
 746
 747     case _SC_ULONG_MAX:
 748       return ULONG_MAX;
 749
 750     case _SC_USHRT_MAX:
 751       return USHRT_MAX;
 752
 753     case _SC_NL_ARGMAX:
 754 #ifdef  NL_ARGMAX
 755       return NL_ARGMAX;
 756 #else
 757       return -1;
 758 #endif
 759
 760     case _SC_NL_LANGMAX:
 761 #ifdef  NL_LANGMAX
 762       return NL_LANGMAX;
 763 #else
 764       return -1;
 765 #endif
 766
 767     case _SC_NL_MSGMAX:
 768 #ifdef  NL_MSGMAX
 769       return NL_MSGMAX;
 770 #else
 771       return -1;
 772 #endif
 773
 774     case _SC_NL_NMAX:
 775 #ifdef  NL_NMAX
 776       return NL_NMAX;
 777 #else
 778       return -1;
 779 #endif
 780
 781     case _SC_NL_SETMAX:
 782 #ifdef  NL_SETMAX
 783       return NL_SETMAX;
 784 #else
 785       return -1;
 786 #endif
 787
 788     case _SC_NL_TEXTMAX:
 789 #ifdef  NL_TEXTMAX
 790       return NL_TEXTMAX;
 791 #else
 792       return -1;
 793 #endif
 794
 795 #define START_ENV_GROUP(VERSION)                \
 796       /* Empty.  */
 797
 798 #define END_ENV_GROUP(VERSION)                  \
 799       /* Empty.  */
 800
 801 #define KNOWN_ABSENT_ENVIRONMENT(SC_PREFIX, ENV_PREFIX, SUFFIX) \
 802     case _SC_##SC_PREFIX##_##SUFFIX:                            \
 803       return _##ENV_PREFIX##_##SUFFIX;
 804
 805 #define KNOWN_PRESENT_ENVIRONMENT(SC_PREFIX, ENV_PREFIX, SUFFIX)        \
 806     case _SC_##SC_PREFIX##_##SUFFIX:                                    \
 807       return _##ENV_PREFIX##_##SUFFIX;
 808
 809 #define UNKNOWN_ENVIRONMENT(SC_PREFIX, ENV_PREFIX, SUFFIX)      \
 810     case _SC_##SC_PREFIX##_##SUFFIX:                            \
 811       return __sysconf_check_spec (#SUFFIX);
 812
 813 #include <posix/posix-envs.def>
 814
 815 #undef START_ENV_GROUP
 816 #undef END_ENV_GROUP
 817 #undef KNOWN_ABSENT_ENVIRONMENT
 818 #undef KNOWN_PRESENT_ENVIRONMENT
 819 #undef UNKNOWN_ENVIRONMENT
 820
 821     case _SC_XOPEN_LEGACY:
 822       return _XOPEN_LEGACY;
 823
 824     case _SC_XOPEN_REALTIME:
 825 #ifdef _XOPEN_REALTIME
 826       return _XOPEN_REALTIME;
 827 #else
 828       return -1;
 829 #endif
 830     case _SC_XOPEN_REALTIME_THREADS:
 831 #ifdef _XOPEN_REALTIME_THREADS
 832       return _XOPEN_REALTIME_THREADS;
 833 #else
 834       return -1;
 835 #endif
 836
 837     case _SC_ADVISORY_INFO:
 838 #if CONF_IS_DEFINED_SET (_POSIX_ADVISORY_INFO)
 839       return _POSIX_ADVISORY_INFO;
 840 #else
 841       return -1;
 842 #endif
 843
 844     case _SC_BARRIERS:
 845 #if CONF_IS_DEFINED_SET (_POSIX_BARRIERS)
 846       return _POSIX_BARRIERS;
 847 #else
 848       return -1;
 849 #endif
 850
 851     case _SC_BASE:
 852 #if CONF_IS_DEFINED_SET (_POSIX_BASE)
 853       return _POSIX_BASE;
 854 #else
 855       return -1;
 856 #endif
 857     case _SC_C_LANG_SUPPORT:
 858 #if CONF_IS_DEFINED_SET (_POSIX_C_LANG_SUPPORT)
 859       return _POSIX_C_LANG_SUPPORT;
 860 #else
 861       return -1;
 862 #endif
 863     case _SC_C_LANG_SUPPORT_R:
 864 #if CONF_IS_DEFINED_SET (_POSIX_C_LANG_SUPPORT_R)
 865       return _POSIX_C_LANG_SUPPORT_R;
 866 #else
 867       return -1;
 868 #endif
 869
 870     case _SC_CLOCK_SELECTION:
 871 #if CONF_IS_DEFINED_SET (_POSIX_CLOCK_SELECTION)
 872       return _POSIX_CLOCK_SELECTION;
 873 #else
 874       return -1;
 875 #endif
 876
 877     case _SC_CPUTIME:
 878 #if CONF_IS_DEFINED_SET (_POSIX_CPUTIME)
 879       return _POSIX_CPUTIME;
 880 #else
 881       return -1;
 882 #endif
 883
 884     case _SC_DEVICE_IO:
 885 #if CONF_IS_DEFINED_SET (_POSIX_DEVICE_IO)
 886       return _POSIX_DEVICE_IO;
 887 #else
 888       return -1;
 889 #endif
 890     case _SC_DEVICE_SPECIFIC:
 891 #if CONF_IS_DEFINED_SET (_POSIX_DEVICE_SPECIFIC)
 892       return _POSIX_DEVICE_SPECIFIC;
 893 #else
 894       return -1;
 895 #endif
 896     case _SC_DEVICE_SPECIFIC_R:
 897 #if CONF_IS_DEFINED_SET (_POSIX_DEVICE_SPECIFIC_R)
 898       return _POSIX_DEVICE_SPECIFIC_R;
 899 #else
 900       return -1;
 901 #endif
 902
 903     case _SC_FD_MGMT:
 904 #if CONF_IS_DEFINED_SET (_POSIX_FD_MGMT)
 905       return _POSIX_FD_MGMT;
 906 #else
 907       return -1;
 908 #endif
 909
 910     case _SC_FIFO:
 911 #if CONF_IS_DEFINED_SET (_POSIX_FIFO)
 912       return _POSIX_FIFO;
 913 #else
 914       return -1;
 915 #endif
 916     case _SC_PIPE:
 917 #if CONF_IS_DEFINED_SET (_POSIX_PIPE)
 918       return _POSIX_PIPE;
 919 #else
 920       return -1;
 921 #endif
 922
 923     case _SC_FILE_ATTRIBUTES:
 924 #if CONF_IS_DEFINED_SET (_POSIX_FILE_ATTRIBUTES)
 925       return _POSIX_FILE_ATTRIBUTES;
 926 #else
 927       return -1;
 928 #endif
 929     case _SC_FILE_LOCKING:
 930 #if CONF_IS_DEFINED_SET (_POSIX_FILE_LOCKING)
 931       return _POSIX_FILE_LOCKING;
 932 #else
 933       return -1;
 934 #endif
 935     case _SC_FILE_SYSTEM:
 936 #if CONF_IS_DEFINED_SET (_POSIX_FILE_SYSTEM)
 937       return _POSIX_FILE_SYSTEM;
 938 #else
 939       return -1;
 940 #endif
 941
 942     case _SC_MONOTONIC_CLOCK:
 943 #if CONF_IS_DEFINED_SET (_POSIX_MONOTONIC_CLOCK)
 944       return _POSIX_MONOTONIC_CLOCK;
 945 #else
 946       return -1;
 947 #endif
 948
 949     case _SC_MULTI_PROCESS:
 950 #if CONF_IS_DEFINED_SET (_POSIX_MULTI_PROCESS)
 951       return _POSIX_MULTI_PROCESS;
 952 #else
 953       return -1;
 954 #endif
 955     case _SC_SINGLE_PROCESS:
 956 #if CONF_IS_DEFINED_SET (_POSIX_SINGLE_PROCESS)
 957       return _POSIX_SINGLE_PROCESS;
 958 #else
 959       return -1;
 960 #endif
 961
 962     case _SC_NETWORKING:
 963 #if CONF_IS_DEFINED_SET (_POSIX_NETWORKING)
 964       return _POSIX_NETWORKING;
 965 #else
 966       return -1;
 967 #endif
 968
 969     case _SC_READER_WRITER_LOCKS:
 970 #if CONF_IS_DEFINED_SET (_POSIX_READER_WRITER_LOCKS)
 971       return _POSIX_READER_WRITER_LOCKS;
 972 #else
 973       return -1;
 974 #endif
 975     case _SC_SPIN_LOCKS:
 976 #if CONF_IS_DEFINED_SET (_POSIX_SPIN_LOCKS)
 977       return _POSIX_SPIN_LOCKS;
 978 #else
 979       return -1;
 980 #endif
 981
 982     case _SC_REGEXP:
 983 #if CONF_IS_DEFINED_SET (_POSIX_REGEXP)
 984       return _POSIX_REGEXP;
 985 #else
 986       return -1;
 987 #endif
 988     /* _REGEX_VERSION has been removed with IEEE Std 1003.1-2001/Cor 2-2004,
 989        item XSH/TC2/D6/137.  */
 990     case _SC_REGEX_VERSION:
 991       return -1;
 992
 993     case _SC_SHELL:
 994 #if CONF_IS_DEFINED_SET (_POSIX_SHELL)
 995       return _POSIX_SHELL;
 996 #else
 997       return -1;
 998 #endif
 999
1000     case _SC_SIGNALS:
1001 #if CONF_IS_DEFINED (_POSIX_SIGNALS)
1002       return _POSIX_SIGNALS;
1003 #else
1004       return -1;
1005 #endif
1006
1007     case _SC_SPAWN:
1008 #if CONF_IS_DEFINED_SET (_POSIX_SPAWN)
1009       return _POSIX_SPAWN;
1010 #else
1011       return -1;
1012 #endif
1013
1014     case _SC_SPORADIC_SERVER:
1015 #if CONF_IS_DEFINED_SET (_POSIX_SPORADIC_SERVER)
1016       return _POSIX_SPORADIC_SERVER;
1017 #else
1018       return -1;
1019 #endif
1020     case _SC_THREAD_SPORADIC_SERVER:
1021 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_SPORADIC_SERVER)
1022       return _POSIX_THREAD_SPORADIC_SERVER;
1023 #else
1024       return -1;
1025 #endif
1026
1027     case _SC_SYSTEM_DATABASE:
1028 #if CONF_IS_DEFINED_SET (_POSIX_SYSTEM_DATABASE)
1029       return _POSIX_SYSTEM_DATABASE;
1030 #else
1031       return -1;
1032 #endif
1033     case _SC_SYSTEM_DATABASE_R:
1034 #if CONF_IS_DEFINED_SET (_POSIX_SYSTEM_DATABASE_R)
1035       return _POSIX_SYSTEM_DATABASE_R;
1036 #else
1037       return -1;
1038 #endif
1039
1040     case _SC_THREAD_CPUTIME:
1041 #if CONF_IS_DEFINED_SET (_POSIX_THREAD_CPUTIME)
1042       return _POSIX_THREAD_CPUTIME;
1043 #else
1044       return -1;
1045 #endif
1046
1047     case _SC_TIMEOUTS:
1048 #if CONF_IS_DEFINED_SET (_POSIX_TIMEOUTS)
1049       return _POSIX_TIMEOUTS;
1050 #else
1051       return -1;
1052 #endif
1053
1054     case _SC_TYPED_MEMORY_OBJECTS:
1055 #if CONF_IS_DEFINED_SET (_POSIX_TYPED_MEMORY_OBJECTS)
1056       return _POSIX_TYPED_MEMORY_OBJECTS;
1057 #else
1058       return -1;
1059 #endif
1060
1061     case _SC_USER_GROUPS:
1062 #if CONF_IS_DEFINED_SET (_POSIX_USER_GROUPS)
1063       return _POSIX_USER_GROUPS;
1064 #else
1065       return -1;
1066 #endif
1067     case _SC_USER_GROUPS_R:
1068 #if CONF_IS_DEFINED_SET (_POSIX_USER_GROUPS_R)
1069       return _POSIX_USER_GROUPS_R;
1070 #else
1071       return -1;
1072 #endif
1073
1074     case _SC_2_PBS:
1075 #ifdef _POSIX2_PBS
1076       return _POSIX2_PBS;
1077 #else
1078       return -1;
1079 #endif
1080     case _SC_2_PBS_ACCOUNTING:
1081 #ifdef _POSIX2_PBS_ACCOUNTING
1082       return _POSIX2_PBS_ACCOUNTING;
1083 #else
1084       return -1;
1085 #endif
1086     case _SC_2_PBS_CHECKPOINT:
1087 #ifdef _POSIX2_PBS_CHECKPOINT
1088       return _POSIX2_PBS_CHECKPOINT;
1089 #else
1090       return -1;
1091 #endif
1092     case _SC_2_PBS_LOCATE:
1093 #ifdef _POSIX2_PBS_LOCATE
1094       return _POSIX2_PBS_LOCATE;
1095 #else
1096       return -1;
1097 #endif
1098     case _SC_2_PBS_MESSAGE:
1099 #ifdef _POSIX2_PBS_MESSAGE
1100       return _POSIX2_PBS_MESSAGE;
1101 #else
1102       return -1;
1103 #endif
1104     case _SC_2_PBS_TRACK:
1105 #ifdef _POSIX2_PBS_TRACK
1106       return _POSIX2_PBS_TRACK;
1107 #else
1108       return -1;
1109 #endif
1110
1111     case _SC_SYMLOOP_MAX:
1112 #ifdef SYMLOOP_MAX
1113       return SYMLOOP_MAX;
1114 #else
1115       return -1;
1116 #endif
1117
1118     case _SC_STREAMS:
1119 #ifdef _XOPEN_STREAMS
1120       return _XOPEN_STREAMS;
1121 #else
1122       return -1;
1123 #endif
1124
1125     case _SC_HOST_NAME_MAX:
1126 #ifdef HOST_NAME_MAX
1127       return HOST_NAME_MAX;
1128 #else
1129       return -1;
1130 #endif
1131
1132     case _SC_TRACE:
1133 #if CONF_IS_DEFINED_SET (_POSIX_TRACE)
1134       return _POSIX_TRACE;
1135 #else
1136       return -1;
1137 #endif
1138     case _SC_TRACE_EVENT_FILTER:
1139 #if CONF_IS_DEFINED_SET (_POSIX_TRACE_EVENT_FILTER)
1140       return _POSIX_TRACE_EVENT_FILTER;
1141 #else
1142       return -1;
1143 #endif
1144     case _SC_TRACE_INHERIT:
1145 #if CONF_IS_DEFINED_SET (_POSIX_TRACE_INHERIT)
1146       return _POSIX_TRACE_INHERIT;
1147 #else
1148       return -1;
1149 #endif
1150     case _SC_TRACE_LOG:
1151 #if CONF_IS_DEFINED_SET (_POSIX_TRACE_LOG)
1152       return _POSIX_TRACE_LOG;
1153 #else
1154       return -1;
1155 #endif
1156
1157     case _SC_TRACE_EVENT_NAME_MAX:
1158     case _SC_TRACE_NAME_MAX:
1159     case _SC_TRACE_SYS_MAX:
1160     case _SC_TRACE_USER_EVENT_MAX:
1161       /* No support for tracing.  */
1162
1163     case _SC_XOPEN_STREAMS:
1164       /* No support for STREAMS.  */
1165       return -1;
1166
1167     case _SC_LEVEL1_ICACHE_SIZE:
1168     case _SC_LEVEL1_ICACHE_ASSOC:
1169     case _SC_LEVEL1_ICACHE_LINESIZE:
1170     case _SC_LEVEL1_DCACHE_SIZE:
1171     case _SC_LEVEL1_DCACHE_ASSOC:
1172     case _SC_LEVEL1_DCACHE_LINESIZE:
1173     case _SC_LEVEL2_CACHE_SIZE:
1174     case _SC_LEVEL2_CACHE_ASSOC:
1175     case _SC_LEVEL2_CACHE_LINESIZE:
1176     case _SC_LEVEL3_CACHE_SIZE:
1177     case _SC_LEVEL3_CACHE_ASSOC:
1178     case _SC_LEVEL3_CACHE_LINESIZE:
1179     case _SC_LEVEL4_CACHE_SIZE:
1180     case _SC_LEVEL4_CACHE_ASSOC:
1181     case _SC_LEVEL4_CACHE_LINESIZE:
1182       /* In general we cannot determine these values.  Therefore we
1183          return zero which indicates that no information is
1184          available.  */
1185       return 0;
1186
1187     case _SC_IPV6:
1188 #if CONF_IS_DEFINED_SET (_POSIX_IPV6)
1189       return _POSIX_IPV6;
1190 #else
1191       return -1;
1192 #endif
1193
1194     case _SC_RAW_SOCKETS:
1195 #if CONF_IS_DEFINED_SET (_POSIX_RAW_SOCKETS)
1196       return _POSIX_RAW_SOCKETS;
1197 #else
1198       return -1;
1199 #endif
1200     }
1201 }
1202
1203 #undef __sysconf
1204 weak_alias (__sysconf, sysconf)
1205 libc_hidden_def (__sysconf)
1206
1207 #if NEED_CHECK_SPEC
1208 static long int
1209 __sysconf_check_spec (const char *spec)
1210 {
1211   int save_errno = errno;
1212
1213   const char *getconf_dir = __libc_secure_getenv ("GETCONF_DIR") ?: GETCONF_DIR;
1214   size_t getconf_dirlen = strlen (getconf_dir);
1215   size_t speclen = strlen (spec);
1216
1217   char name[getconf_dirlen + sizeof ("/POSIX_V6_") + speclen];
1218   memcpy (mempcpy (mempcpy (name, getconf_dir, getconf_dirlen),
1219                    "/POSIX_V6_", sizeof ("/POSIX_V6_") - 1),
1220           spec, speclen + 1);
1221
1222   struct stat64 st;
1223   long int ret = __xstat64 (_STAT_VER, name, &st) >= 0 ? 1 : -1;
1224
1225   __set_errno (save_errno);
1226   return ret;
1227 }
1228 #endif