예제 #1
0
파일: arena.c 프로젝트: Ace-Tang/glibc
static mstate
internal_function
arena_get2 (mstate a_tsd, size_t size, mstate avoid_arena)
{
  mstate a;

  static size_t narenas_limit;

  a = get_free_list ();
  if (a == NULL)
    {
      /* Nothing immediately available, so generate a new arena.  */
      if (narenas_limit == 0)
        {
          if (mp_.arena_max != 0)
            narenas_limit = mp_.arena_max;
          else if (narenas > mp_.arena_test)
            {
              int n = __get_nprocs ();

              if (n >= 1)
                narenas_limit = NARENAS_FROM_NCORES (n);
              else
                /* We have no information about the system.  Assume two
                   cores.  */
                narenas_limit = NARENAS_FROM_NCORES (2);
            }
        }
    repeat:;
      size_t n = narenas;
      /* NB: the following depends on the fact that (size_t)0 - 1 is a
         very large number and that the underflow is OK.  If arena_max
         is set the value of arena_test is irrelevant.  If arena_test
         is set but narenas is not yet larger or equal to arena_test
         narenas_limit is 0.  There is no possibility for narenas to
         be too big for the test to always fail since there is not
         enough address space to create that many arenas.  */
      if (__glibc_unlikely (n <= narenas_limit - 1))
        {
          if (catomic_compare_and_exchange_bool_acq (&narenas, n + 1, n))
            goto repeat;
          a = _int_new_arena (size);
	  if (__glibc_unlikely (a == NULL))
            catomic_decrement (&narenas);
        }
      else
        a = reused_arena (avoid_arena);
    }
  return a;
}
예제 #2
0
파일: arena.c 프로젝트: Xilinx/eglibc
static mstate
internal_function
arena_get2(mstate a_tsd, size_t size, mstate avoid_arena)
{
  mstate a;

#ifdef PER_THREAD
  static size_t narenas_limit;

  a = get_free_list ();
  if (a == NULL)
    {
      /* Nothing immediately available, so generate a new arena.  */
      if (narenas_limit == 0)
	{
	  if (mp_.arena_max != 0)
	    narenas_limit = mp_.arena_max;
	  else if (narenas > mp_.arena_test)
	    {
	      int n  = __get_nprocs ();

	      if (n >= 1)
		narenas_limit = NARENAS_FROM_NCORES (n);
	      else
		/* We have no information about the system.  Assume two
		   cores.  */
		narenas_limit = NARENAS_FROM_NCORES (2);
	    }
	}
    repeat:;
      size_t n = narenas;
      /* NB: the following depends on the fact that (size_t)0 - 1 is a
	 very large number and that the underflow is OK.  If arena_max
	 is set the value of arena_test is irrelevant.  If arena_test
	 is set but narenas is not yet larger or equal to arena_test
	 narenas_limit is 0.  There is no possibility for narenas to
	 be too big for the test to always fail since there is not
	 enough address space to create that many arenas.  */
      if (__builtin_expect (n <= narenas_limit - 1, 0))
	{
	  if (catomic_compare_and_exchange_bool_acq (&narenas, n + 1, n))
	    goto repeat;
	  a = _int_new_arena (size);
	  if (__builtin_expect (a == NULL, 0))
	    catomic_decrement (&narenas);
	}
      else
	a = reused_arena (avoid_arena);
    }
#else
  if(!a_tsd)
    a = a_tsd = &main_arena;
  else {
    a = a_tsd->next;
    if(!a) {
      /* This can only happen while initializing the new arena. */
      (void)mutex_lock(&main_arena.mutex);
      THREAD_STAT(++(main_arena.stat_lock_wait));
      return &main_arena;
    }
  }

  /* Check the global, circularly linked list for available arenas. */
  bool retried = false;
 repeat:
  do {
    if(!mutex_trylock(&a->mutex)) {
      if (retried)
	(void)mutex_unlock(&list_lock);
      THREAD_STAT(++(a->stat_lock_loop));
      tsd_setspecific(arena_key, (void *)a);
      return a;
    }
    a = a->next;
  } while(a != a_tsd);

  /* If not even the list_lock can be obtained, try again.  This can
     happen during `atfork', or for example on systems where thread
     creation makes it temporarily impossible to obtain _any_
     locks. */
  if(!retried && mutex_trylock(&list_lock)) {
    /* We will block to not run in a busy loop.  */
    (void)mutex_lock(&list_lock);

    /* Since we blocked there might be an arena available now.  */
    retried = true;
    a = a_tsd;
    goto repeat;
  }

  /* Nothing immediately available, so generate a new arena.  */
  a = _int_new_arena(size);
  (void)mutex_unlock(&list_lock);
#endif

  return a;
}
예제 #3
0
/* Get the value of the system variable NAME.  */
long int
__sysconf (int name)
{
  switch (name)
    {
      /* Also add obsolete or unnecessarily added constants here.  */
    case _SC_EQUIV_CLASS_MAX:
    default:
      __set_errno (EINVAL);
      return -1;

    case _SC_ARG_MAX:
#ifdef	ARG_MAX
      return ARG_MAX;
#else
      return -1;
#endif

    case _SC_CHILD_MAX:
#ifdef	CHILD_MAX
      return CHILD_MAX;
#else
      return __get_child_max ();
#endif

    case _SC_CLK_TCK:
      return __getclktck ();

    case _SC_NGROUPS_MAX:
#ifdef	NGROUPS_MAX
      return NGROUPS_MAX;
#else
      return -1;
#endif

    case _SC_OPEN_MAX:
      return __getdtablesize ();

    case _SC_STREAM_MAX:
#ifdef	STREAM_MAX
      return STREAM_MAX;
#else
      return FOPEN_MAX;
#endif

    case _SC_TZNAME_MAX:
      return MAX (__tzname_max (), _POSIX_TZNAME_MAX);

    case _SC_JOB_CONTROL:
#if CONF_IS_DEFINED_SET (_POSIX_JOB_CONTROL)
      return _POSIX_JOB_CONTROL;
#else
      return -1;
#endif

    case _SC_SAVED_IDS:
#if CONF_IS_DEFINED_SET (_POSIX_SAVED_IDS)
      return 1;
#else
      return -1;
#endif

    case _SC_REALTIME_SIGNALS:
#if CONF_IS_DEFINED_SET (_POSIX_REALTIME_SIGNALS)
      return _POSIX_REALTIME_SIGNALS;
#else
      return -1;
#endif

    case _SC_PRIORITY_SCHEDULING:
#if CONF_IS_DEFINED_SET (_POSIX_PRIORITY_SCHEDULING)
      return _POSIX_PRIORITY_SCHEDULING;
#else
      return -1;
#endif

    case _SC_TIMERS:
#if CONF_IS_DEFINED_SET (_POSIX_TIMERS)
      return _POSIX_TIMERS;
#else
      return -1;
#endif

    case _SC_ASYNCHRONOUS_IO:
#if CONF_IS_DEFINED_SET (_POSIX_ASYNCHRONOUS_IO)
      return _POSIX_ASYNCHRONOUS_IO;
#else
      return -1;
#endif

    case _SC_PRIORITIZED_IO:
#if CONF_IS_DEFINED_SET (_POSIX_PRIORITIZED_IO)
      return _POSIX_PRIORITIZED_IO;
#else
      return -1;
#endif

    case _SC_SYNCHRONIZED_IO:
#if CONF_IS_DEFINED_SET (_POSIX_SYNCHRONIZED_IO)
      return _POSIX_SYNCHRONIZED_IO;
#else
      return -1;
#endif

    case _SC_FSYNC:
#if CONF_IS_DEFINED_SET (_POSIX_FSYNC)
      return _POSIX_FSYNC;
#else
      return -1;
#endif

    case _SC_MAPPED_FILES:
#if CONF_IS_DEFINED_SET (_POSIX_MAPPED_FILES)
      return _POSIX_MAPPED_FILES;
#else
      return -1;
#endif

    case _SC_MEMLOCK:
#if CONF_IS_DEFINED_SET (_POSIX_MEMLOCK)
      return _POSIX_MEMLOCK;
#else
      return -1;
#endif

    case _SC_MEMLOCK_RANGE:
#if CONF_IS_DEFINED_SET (_POSIX_MEMLOCK_RANGE)
      return _POSIX_MEMLOCK_RANGE;
#else
      return -1;
#endif

    case _SC_MEMORY_PROTECTION:
#if CONF_IS_DEFINED_SET (_POSIX_MEMORY_PROTECTION)
      return _POSIX_MEMORY_PROTECTION;
#else
      return -1;
#endif

    case _SC_MESSAGE_PASSING:
#if CONF_IS_DEFINED_SET (_POSIX_MESSAGE_PASSING)
      return _POSIX_MESSAGE_PASSING;
#else
      return -1;
#endif

    case _SC_SEMAPHORES:
#if CONF_IS_DEFINED_SET (_POSIX_SEMAPHORES)
      return _POSIX_SEMAPHORES;
#else
      return -1;
#endif

    case _SC_SHARED_MEMORY_OBJECTS:
#if CONF_IS_DEFINED_SET (_POSIX_SHARED_MEMORY_OBJECTS)
      return _POSIX_SHARED_MEMORY_OBJECTS;
#else
      return -1;
#endif

    case _SC_VERSION:
      return _POSIX_VERSION;

    case _SC_PAGESIZE:
      return __getpagesize ();

    case _SC_AIO_LISTIO_MAX:
#ifdef	AIO_LISTIO_MAX
      return AIO_LISTIO_MAX;
#else
      return -1;
#endif

    case _SC_AIO_MAX:
#ifdef	AIO_MAX
      return AIO_MAX;
#else
      return -1;
#endif

    case _SC_AIO_PRIO_DELTA_MAX:
#ifdef	AIO_PRIO_DELTA_MAX
      return AIO_PRIO_DELTA_MAX;
#else
      return -1;
#endif

    case _SC_DELAYTIMER_MAX:
#ifdef	DELAYTIMER_MAX
      return DELAYTIMER_MAX;
#else
      return -1;
#endif

    case _SC_MQ_OPEN_MAX:
#ifdef	MQ_OPEN_MAX
      return MQ_OPEN_MAX;
#else
      return -1;
#endif

    case _SC_MQ_PRIO_MAX:
#ifdef	MQ_PRIO_MAX
      return MQ_PRIO_MAX;
#else
      return -1;
#endif

    case _SC_RTSIG_MAX:
#ifdef	RTSIG_MAX
      return RTSIG_MAX;
#else
      return -1;
#endif

    case _SC_SEM_NSEMS_MAX:
#ifdef	SEM_NSEMS_MAX
      return SEM_NSEMS_MAX;
#else
      return -1;
#endif

    case _SC_SEM_VALUE_MAX:
#ifdef	SEM_VALUE_MAX
      return SEM_VALUE_MAX;
#else
      return -1;
#endif

    case _SC_SIGQUEUE_MAX:
#ifdef	SIGQUEUE_MAX
      return SIGQUEUE_MAX;
#else
      return -1;
#endif

    case _SC_TIMER_MAX:
#ifdef	TIMER_MAX
      return TIMER_MAX;
#else
      return -1;
#endif

    case _SC_BC_BASE_MAX:
#ifdef	BC_BASE_MAX
      return BC_BASE_MAX;
#else
      return -1;
#endif

    case _SC_BC_DIM_MAX:
#ifdef	BC_DIM_MAX
      return BC_DIM_MAX;
#else
      return -1;
#endif

    case _SC_BC_SCALE_MAX:
#ifdef	BC_SCALE_MAX
      return BC_SCALE_MAX;
#else
      return -1;
#endif

    case _SC_BC_STRING_MAX:
#ifdef	BC_STRING_MAX
      return BC_STRING_MAX;
#else
      return -1;
#endif

    case _SC_COLL_WEIGHTS_MAX:
#ifdef	COLL_WEIGHTS_MAX
      return COLL_WEIGHTS_MAX;
#else
      return -1;
#endif

    case _SC_EXPR_NEST_MAX:
#ifdef	EXPR_NEST_MAX
      return EXPR_NEST_MAX;
#else
      return -1;
#endif

    case _SC_LINE_MAX:
#ifdef	LINE_MAX
      return LINE_MAX;
#else
      return -1;
#endif

    case _SC_RE_DUP_MAX:
#ifdef	RE_DUP_MAX
      return RE_DUP_MAX;
#else
      return -1;
#endif

    case _SC_CHARCLASS_NAME_MAX:
#ifdef	CHARCLASS_NAME_MAX
      return CHARCLASS_NAME_MAX;
#else
      return -1;
#endif

    case _SC_PII:
#if CONF_IS_DEFINED_SET (_POSIX_PII)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_XTI:
#if CONF_IS_DEFINED_SET (_POSIX_PII_XTI)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_SOCKET:
#if CONF_IS_DEFINED_SET (_POSIX_PII_SOCKET)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_INTERNET:
#if CONF_IS_DEFINED_SET (_POSIX_PII_INTERNET)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_OSI:
#if CONF_IS_DEFINED_SET (_POSIX_PII_OSI)
      return 1;
#else
      return -1;
#endif

    case _SC_POLL:
#if CONF_IS_DEFINED_SET (_POSIX_POLL)
      return 1;
#else
      return -1;
#endif

    case _SC_SELECT:
#if CONF_IS_DEFINED_SET (_POSIX_SELECT)
      return 1;
#else
      return -1;
#endif

      /* The same as _SC_IOV_MAX.  */
    case _SC_UIO_MAXIOV:
#ifdef	UIO_MAXIOV
      return UIO_MAXIOV;
#else
      return -1;
#endif

    case _SC_PII_INTERNET_STREAM:
#if CONF_IS_DEFINED_SET (_POSIX_PII_INTERNET_STREAM)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_INTERNET_DGRAM:
#if CONF_IS_DEFINED_SET (_POSIX_PII_INTERNET_DGRAM)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_OSI_COTS:
#if CONF_IS_DEFINED_SET (_POSIX_PII_OSI_COTS)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_OSI_CLTS:
#if CONF_IS_DEFINED_SET (_POSIX_PII_OSI_CLTS)
      return 1;
#else
      return -1;
#endif

    case _SC_PII_OSI_M:
#if CONF_IS_DEFINED_SET (_POSIX_PII_OSI_M)
      return 1;
#else
      return -1;
#endif

    case _SC_T_IOV_MAX:
#ifdef	_T_IOV_MAX
      return _T_IOV_MAX;
#else
      return -1;
#endif

    case _SC_2_VERSION:
      return _POSIX2_VERSION;

    case _SC_2_C_BIND:
#ifdef	_POSIX2_C_BIND
      return _POSIX2_C_BIND;
#else
      return -1;
#endif

    case _SC_2_C_DEV:
#ifdef	_POSIX2_C_DEV
      return _POSIX2_C_DEV;
#else
      return -1;
#endif

    case _SC_2_C_VERSION:
#ifdef	_POSIX2_C_VERSION
      return _POSIX2_C_VERSION;
#else
      return -1;
#endif

    case _SC_2_FORT_DEV:
#ifdef	_POSIX2_FORT_DEV
      return _POSIX2_FORT_DEV;
#else
      return -1;
#endif

    case _SC_2_FORT_RUN:
#ifdef	_POSIX2_FORT_RUN
      return _POSIX2_FORT_RUN;
#else
      return -1;
#endif

    case _SC_2_LOCALEDEF:
#ifdef	_POSIX2_LOCALEDEF
      return _POSIX2_LOCALEDEF;
#else
      return -1;
#endif

    case _SC_2_SW_DEV:
#ifdef	_POSIX2_SW_DEV
      return _POSIX2_SW_DEV;
#else
      return -1;
#endif

    case _SC_2_CHAR_TERM:
#ifdef	_POSIX2_CHAR_TERM
      return _POSIX2_CHAR_TERM;
#else
      return -1;
#endif

    case _SC_2_UPE:
#ifdef	_POSIX2_UPE
      return _POSIX2_UPE;
#else
      return -1;
#endif

      /* POSIX 1003.1c (POSIX Threads).  */
    case _SC_THREADS:
#if CONF_IS_DEFINED_SET (_POSIX_THREADS)
      return _POSIX_THREADS;
#else
      return -1;
#endif

    case _SC_THREAD_SAFE_FUNCTIONS:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_SAFE_FUNCTIONS)
      return _POSIX_THREAD_SAFE_FUNCTIONS;
#else
      return -1;
#endif

    case _SC_GETGR_R_SIZE_MAX:
      return NSS_BUFLEN_GROUP;

    case _SC_GETPW_R_SIZE_MAX:
      return NSS_BUFLEN_PASSWD;

    case _SC_LOGIN_NAME_MAX:
#ifdef	LOGIN_NAME_MAX
      return LOGIN_NAME_MAX;
#else
      return -1;
#endif

    case _SC_TTY_NAME_MAX:
#ifdef	TTY_NAME_MAX
      return TTY_NAME_MAX;
#else
      return -1;
#endif

    case _SC_THREAD_DESTRUCTOR_ITERATIONS:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_DESTRUCTOR_ITERATIONS)
      return _POSIX_THREAD_DESTRUCTOR_ITERATIONS;
#else
      return -1;
#endif

    case _SC_THREAD_KEYS_MAX:
#ifdef	PTHREAD_KEYS_MAX
      return PTHREAD_KEYS_MAX;
#else
      return -1;
#endif

    case _SC_THREAD_STACK_MIN:
#ifdef	PTHREAD_STACK_MIN
      return PTHREAD_STACK_MIN;
#else
      return -1;
#endif

    case _SC_THREAD_THREADS_MAX:
#ifdef	PTHREAD_THREADS_MAX
      return PTHREAD_THREADS_MAX;
#else
      return -1;
#endif

    case _SC_THREAD_ATTR_STACKADDR:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_ATTR_STACKADDR)
      return _POSIX_THREAD_ATTR_STACKADDR;
#else
      return -1;
#endif

    case _SC_THREAD_ATTR_STACKSIZE:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_ATTR_STACKSIZE)
      return _POSIX_THREAD_ATTR_STACKSIZE;
#else
      return -1;
#endif

    case _SC_THREAD_PRIORITY_SCHEDULING:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_PRIORITY_SCHEDULING)
      return _POSIX_THREAD_PRIORITY_SCHEDULING;
#else
      return -1;
#endif

    case _SC_THREAD_PRIO_INHERIT:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_PRIO_INHERIT)
      return _POSIX_THREAD_PRIO_INHERIT;
#else
      return -1;
#endif

    case _SC_THREAD_PRIO_PROTECT:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_PRIO_PROTECT)
      return _POSIX_THREAD_PRIO_PROTECT;
#else
      return -1;
#endif

    case _SC_THREAD_PROCESS_SHARED:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_PROCESS_SHARED)
      return _POSIX_THREAD_PROCESS_SHARED;
#else
      return -1;
#endif

    case _SC_NPROCESSORS_CONF:
      return __get_nprocs_conf ();

    case _SC_NPROCESSORS_ONLN:
      return __get_nprocs ();

    case _SC_PHYS_PAGES:
      return __get_phys_pages ();

    case _SC_AVPHYS_PAGES:
      return __get_avphys_pages ();

    case _SC_ATEXIT_MAX:
      /* We have no limit since we use lists.  */
      return INT_MAX;

    case _SC_PASS_MAX:
      /* We have no limit but since the return value might be used to
	 allocate a buffer we restrict the value.  */
      return BUFSIZ;

    case _SC_XOPEN_VERSION:
      return _XOPEN_VERSION;

    case _SC_XOPEN_XCU_VERSION:
      return _XOPEN_XCU_VERSION;

    case _SC_XOPEN_UNIX:
      return _XOPEN_UNIX;

    case _SC_XOPEN_CRYPT:
#ifdef	_XOPEN_CRYPT
      return _XOPEN_CRYPT;
#else
      return -1;
#endif

    case _SC_XOPEN_ENH_I18N:
#ifdef	_XOPEN_ENH_I18N
      return _XOPEN_ENH_I18N;
#else
      return -1;
#endif

    case _SC_XOPEN_SHM:
#ifdef	_XOPEN_SHM
      return _XOPEN_SHM;
#else
      return -1;
#endif

    case _SC_XOPEN_XPG2:
#ifdef	_XOPEN_XPG2
      return _XOPEN_XPG2;
#else
      return -1;
#endif

    case _SC_XOPEN_XPG3:
#ifdef	_XOPEN_XPG3
      return _XOPEN_XPG3;
#else
      return -1;
#endif

    case _SC_XOPEN_XPG4:
#ifdef	_XOPEN_XPG4
      return _XOPEN_XPG4;
#else
      return -1;
#endif

    case _SC_CHAR_BIT:
      return CHAR_BIT;

    case _SC_CHAR_MAX:
      return CHAR_MAX;

    case _SC_CHAR_MIN:
      return CHAR_MIN;

    case _SC_INT_MAX:
      return INT_MAX;

    case _SC_INT_MIN:
      return INT_MIN;

    case _SC_LONG_BIT:
      return sizeof (long int) * CHAR_BIT;

    case _SC_WORD_BIT:
      return sizeof (int) * CHAR_BIT;

    case _SC_MB_LEN_MAX:
      return MB_LEN_MAX;

    case _SC_NZERO:
      return NZERO;

    case _SC_SSIZE_MAX:
      return _POSIX_SSIZE_MAX;

    case _SC_SCHAR_MAX:
      return SCHAR_MAX;

    case _SC_SCHAR_MIN:
      return SCHAR_MIN;

    case _SC_SHRT_MAX:
      return SHRT_MAX;

    case _SC_SHRT_MIN:
      return SHRT_MIN;

    case _SC_UCHAR_MAX:
      return UCHAR_MAX;

    case _SC_UINT_MAX:
      return UINT_MAX;

    case _SC_ULONG_MAX:
      return ULONG_MAX;

    case _SC_USHRT_MAX:
      return USHRT_MAX;

    case _SC_NL_ARGMAX:
#ifdef	NL_ARGMAX
      return NL_ARGMAX;
#else
      return -1;
#endif

    case _SC_NL_LANGMAX:
#ifdef	NL_LANGMAX
      return NL_LANGMAX;
#else
      return -1;
#endif

    case _SC_NL_MSGMAX:
#ifdef	NL_MSGMAX
      return NL_MSGMAX;
#else
      return -1;
#endif

    case _SC_NL_NMAX:
#ifdef	NL_NMAX
      return NL_NMAX;
#else
      return -1;
#endif

    case _SC_NL_SETMAX:
#ifdef	NL_SETMAX
      return NL_SETMAX;
#else
      return -1;
#endif

    case _SC_NL_TEXTMAX:
#ifdef	NL_TEXTMAX
      return NL_TEXTMAX;
#else
      return -1;
#endif

#define START_ENV_GROUP(VERSION)		\
      /* Empty.  */

#define END_ENV_GROUP(VERSION)			\
      /* Empty.  */

#define KNOWN_ABSENT_ENVIRONMENT(SC_PREFIX, ENV_PREFIX, SUFFIX)	\
    case _SC_##SC_PREFIX##_##SUFFIX:				\
      return _##ENV_PREFIX##_##SUFFIX;

#define KNOWN_PRESENT_ENVIRONMENT(SC_PREFIX, ENV_PREFIX, SUFFIX)	\
    case _SC_##SC_PREFIX##_##SUFFIX:					\
      return _##ENV_PREFIX##_##SUFFIX;

#define UNKNOWN_ENVIRONMENT(SC_PREFIX, ENV_PREFIX, SUFFIX)	\
    case _SC_##SC_PREFIX##_##SUFFIX:				\
      return __sysconf_check_spec (#SUFFIX);

#include <posix/posix-envs.def>

#undef START_ENV_GROUP
#undef END_ENV_GROUP
#undef KNOWN_ABSENT_ENVIRONMENT
#undef KNOWN_PRESENT_ENVIRONMENT
#undef UNKNOWN_ENVIRONMENT

    case _SC_XOPEN_LEGACY:
      return _XOPEN_LEGACY;

    case _SC_XOPEN_REALTIME:
#ifdef _XOPEN_REALTIME
      return _XOPEN_REALTIME;
#else
      return -1;
#endif
    case _SC_XOPEN_REALTIME_THREADS:
#ifdef _XOPEN_REALTIME_THREADS
      return _XOPEN_REALTIME_THREADS;
#else
      return -1;
#endif

    case _SC_ADVISORY_INFO:
#if CONF_IS_DEFINED_SET (_POSIX_ADVISORY_INFO)
      return _POSIX_ADVISORY_INFO;
#else
      return -1;
#endif

    case _SC_BARRIERS:
#if CONF_IS_DEFINED_SET (_POSIX_BARRIERS)
      return _POSIX_BARRIERS;
#else
      return -1;
#endif

    case _SC_BASE:
#if CONF_IS_DEFINED_SET (_POSIX_BASE)
      return _POSIX_BASE;
#else
      return -1;
#endif
    case _SC_C_LANG_SUPPORT:
#if CONF_IS_DEFINED_SET (_POSIX_C_LANG_SUPPORT)
      return _POSIX_C_LANG_SUPPORT;
#else
      return -1;
#endif
    case _SC_C_LANG_SUPPORT_R:
#if CONF_IS_DEFINED_SET (_POSIX_C_LANG_SUPPORT_R)
      return _POSIX_C_LANG_SUPPORT_R;
#else
      return -1;
#endif

    case _SC_CLOCK_SELECTION:
#if CONF_IS_DEFINED_SET (_POSIX_CLOCK_SELECTION)
      return _POSIX_CLOCK_SELECTION;
#else
      return -1;
#endif

    case _SC_CPUTIME:
#if CONF_IS_DEFINED_SET (_POSIX_CPUTIME)
      return _POSIX_CPUTIME;
#else
      return -1;
#endif

    case _SC_DEVICE_IO:
#if CONF_IS_DEFINED_SET (_POSIX_DEVICE_IO)
      return _POSIX_DEVICE_IO;
#else
      return -1;
#endif
    case _SC_DEVICE_SPECIFIC:
#if CONF_IS_DEFINED_SET (_POSIX_DEVICE_SPECIFIC)
      return _POSIX_DEVICE_SPECIFIC;
#else
      return -1;
#endif
    case _SC_DEVICE_SPECIFIC_R:
#if CONF_IS_DEFINED_SET (_POSIX_DEVICE_SPECIFIC_R)
      return _POSIX_DEVICE_SPECIFIC_R;
#else
      return -1;
#endif

    case _SC_FD_MGMT:
#if CONF_IS_DEFINED_SET (_POSIX_FD_MGMT)
      return _POSIX_FD_MGMT;
#else
      return -1;
#endif

    case _SC_FIFO:
#if CONF_IS_DEFINED_SET (_POSIX_FIFO)
      return _POSIX_FIFO;
#else
      return -1;
#endif
    case _SC_PIPE:
#if CONF_IS_DEFINED_SET (_POSIX_PIPE)
      return _POSIX_PIPE;
#else
      return -1;
#endif

    case _SC_FILE_ATTRIBUTES:
#if CONF_IS_DEFINED_SET (_POSIX_FILE_ATTRIBUTES)
      return _POSIX_FILE_ATTRIBUTES;
#else
      return -1;
#endif
    case _SC_FILE_LOCKING:
#if CONF_IS_DEFINED_SET (_POSIX_FILE_LOCKING)
      return _POSIX_FILE_LOCKING;
#else
      return -1;
#endif
    case _SC_FILE_SYSTEM:
#if CONF_IS_DEFINED_SET (_POSIX_FILE_SYSTEM)
      return _POSIX_FILE_SYSTEM;
#else
      return -1;
#endif

    case _SC_MONOTONIC_CLOCK:
#if CONF_IS_DEFINED_SET (_POSIX_MONOTONIC_CLOCK)
      return _POSIX_MONOTONIC_CLOCK;
#else
      return -1;
#endif

    case _SC_MULTI_PROCESS:
#if CONF_IS_DEFINED_SET (_POSIX_MULTI_PROCESS)
      return _POSIX_MULTI_PROCESS;
#else
      return -1;
#endif
    case _SC_SINGLE_PROCESS:
#if CONF_IS_DEFINED_SET (_POSIX_SINGLE_PROCESS)
      return _POSIX_SINGLE_PROCESS;
#else
      return -1;
#endif

    case _SC_NETWORKING:
#if CONF_IS_DEFINED_SET (_POSIX_NETWORKING)
      return _POSIX_NETWORKING;
#else
      return -1;
#endif

    case _SC_READER_WRITER_LOCKS:
#if CONF_IS_DEFINED_SET (_POSIX_READER_WRITER_LOCKS)
      return _POSIX_READER_WRITER_LOCKS;
#else
      return -1;
#endif
    case _SC_SPIN_LOCKS:
#if CONF_IS_DEFINED_SET (_POSIX_SPIN_LOCKS)
      return _POSIX_SPIN_LOCKS;
#else
      return -1;
#endif

    case _SC_REGEXP:
#if CONF_IS_DEFINED_SET (_POSIX_REGEXP)
      return _POSIX_REGEXP;
#else
      return -1;
#endif
    /* _REGEX_VERSION has been removed with IEEE Std 1003.1-2001/Cor 2-2004,
       item XSH/TC2/D6/137.  */
    case _SC_REGEX_VERSION:
      return -1;

    case _SC_SHELL:
#if CONF_IS_DEFINED_SET (_POSIX_SHELL)
      return _POSIX_SHELL;
#else
      return -1;
#endif

    case _SC_SIGNALS:
#if CONF_IS_DEFINED (_POSIX_SIGNALS)
      return _POSIX_SIGNALS;
#else
      return -1;
#endif

    case _SC_SPAWN:
#if CONF_IS_DEFINED_SET (_POSIX_SPAWN)
      return _POSIX_SPAWN;
#else
      return -1;
#endif

    case _SC_SPORADIC_SERVER:
#if CONF_IS_DEFINED_SET (_POSIX_SPORADIC_SERVER)
      return _POSIX_SPORADIC_SERVER;
#else
      return -1;
#endif
    case _SC_THREAD_SPORADIC_SERVER:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_SPORADIC_SERVER)
      return _POSIX_THREAD_SPORADIC_SERVER;
#else
      return -1;
#endif

    case _SC_SYSTEM_DATABASE:
#if CONF_IS_DEFINED_SET (_POSIX_SYSTEM_DATABASE)
      return _POSIX_SYSTEM_DATABASE;
#else
      return -1;
#endif
    case _SC_SYSTEM_DATABASE_R:
#if CONF_IS_DEFINED_SET (_POSIX_SYSTEM_DATABASE_R)
      return _POSIX_SYSTEM_DATABASE_R;
#else
      return -1;
#endif

    case _SC_THREAD_CPUTIME:
#if CONF_IS_DEFINED_SET (_POSIX_THREAD_CPUTIME)
      return _POSIX_THREAD_CPUTIME;
#else
      return -1;
#endif

    case _SC_TIMEOUTS:
#if CONF_IS_DEFINED_SET (_POSIX_TIMEOUTS)
      return _POSIX_TIMEOUTS;
#else
      return -1;
#endif

    case _SC_TYPED_MEMORY_OBJECTS:
#if CONF_IS_DEFINED_SET (_POSIX_TYPED_MEMORY_OBJECTS)
      return _POSIX_TYPED_MEMORY_OBJECTS;
#else
      return -1;
#endif

    case _SC_USER_GROUPS:
#if CONF_IS_DEFINED_SET (_POSIX_USER_GROUPS)
      return _POSIX_USER_GROUPS;
#else
      return -1;
#endif
    case _SC_USER_GROUPS_R:
#if CONF_IS_DEFINED_SET (_POSIX_USER_GROUPS_R)
      return _POSIX_USER_GROUPS_R;
#else
      return -1;
#endif

    case _SC_2_PBS:
#ifdef _POSIX2_PBS
      return _POSIX2_PBS;
#else
      return -1;
#endif
    case _SC_2_PBS_ACCOUNTING:
#ifdef _POSIX2_PBS_ACCOUNTING
      return _POSIX2_PBS_ACCOUNTING;
#else
      return -1;
#endif
    case _SC_2_PBS_CHECKPOINT:
#ifdef _POSIX2_PBS_CHECKPOINT
      return _POSIX2_PBS_CHECKPOINT;
#else
      return -1;
#endif
    case _SC_2_PBS_LOCATE:
#ifdef _POSIX2_PBS_LOCATE
      return _POSIX2_PBS_LOCATE;
#else
      return -1;
#endif
    case _SC_2_PBS_MESSAGE:
#ifdef _POSIX2_PBS_MESSAGE
      return _POSIX2_PBS_MESSAGE;
#else
      return -1;
#endif
    case _SC_2_PBS_TRACK:
#ifdef _POSIX2_PBS_TRACK
      return _POSIX2_PBS_TRACK;
#else
      return -1;
#endif

    case _SC_SYMLOOP_MAX:
#ifdef SYMLOOP_MAX
      return SYMLOOP_MAX;
#else
      return -1;
#endif

    case _SC_STREAMS:
#ifdef _XOPEN_STREAMS
      return _XOPEN_STREAMS;
#else
      return -1;
#endif

    case _SC_HOST_NAME_MAX:
#ifdef HOST_NAME_MAX
      return HOST_NAME_MAX;
#else
      return -1;
#endif

    case _SC_TRACE:
#if CONF_IS_DEFINED_SET (_POSIX_TRACE)
      return _POSIX_TRACE;
#else
      return -1;
#endif
    case _SC_TRACE_EVENT_FILTER:
#if CONF_IS_DEFINED_SET (_POSIX_TRACE_EVENT_FILTER)
      return _POSIX_TRACE_EVENT_FILTER;
#else
      return -1;
#endif
    case _SC_TRACE_INHERIT:
#if CONF_IS_DEFINED_SET (_POSIX_TRACE_INHERIT)
      return _POSIX_TRACE_INHERIT;
#else
      return -1;
#endif
    case _SC_TRACE_LOG:
#if CONF_IS_DEFINED_SET (_POSIX_TRACE_LOG)
      return _POSIX_TRACE_LOG;
#else
      return -1;
#endif

    case _SC_TRACE_EVENT_NAME_MAX:
    case _SC_TRACE_NAME_MAX:
    case _SC_TRACE_SYS_MAX:
    case _SC_TRACE_USER_EVENT_MAX:
      /* No support for tracing.  */

    case _SC_XOPEN_STREAMS:
      /* No support for STREAMS.  */
      return -1;

    case _SC_LEVEL1_ICACHE_SIZE:
    case _SC_LEVEL1_ICACHE_ASSOC:
    case _SC_LEVEL1_ICACHE_LINESIZE:
    case _SC_LEVEL1_DCACHE_SIZE:
    case _SC_LEVEL1_DCACHE_ASSOC:
    case _SC_LEVEL1_DCACHE_LINESIZE:
    case _SC_LEVEL2_CACHE_SIZE:
    case _SC_LEVEL2_CACHE_ASSOC:
    case _SC_LEVEL2_CACHE_LINESIZE:
    case _SC_LEVEL3_CACHE_SIZE:
    case _SC_LEVEL3_CACHE_ASSOC:
    case _SC_LEVEL3_CACHE_LINESIZE:
    case _SC_LEVEL4_CACHE_SIZE:
    case _SC_LEVEL4_CACHE_ASSOC:
    case _SC_LEVEL4_CACHE_LINESIZE:
      /* In general we cannot determine these values.  Therefore we
	 return zero which indicates that no information is
	 available.  */
      return 0;

    case _SC_IPV6:
#if CONF_IS_DEFINED_SET (_POSIX_IPV6)
      return _POSIX_IPV6;
#else
      return -1;
#endif

    case _SC_RAW_SOCKETS:
#if CONF_IS_DEFINED_SET (_POSIX_RAW_SOCKETS)
      return _POSIX_RAW_SOCKETS;
#else
      return -1;
#endif
    }
}