_limits.h

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/*
 * Copyright (c) 1997
 * Silicon Graphics Computer Systems, Inc.
 *
 * Copyright (c) 1999
 * Boris Fomitchev
 *
 * This material is provided "as is", with absolutely no warranty expressed
 * or implied. Any use is at your own risk.
 *
 * Permission to use or copy this software for any purpose is hereby granted
 * without fee, provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 *
 */

/* NOTE: This may be not portable code. Parts of numeric_limits<> are
 * inherently machine-dependent.  At present this file is suitable
 * for the MIPS, SPARC, Alpha and ia32 architectures.
 */

#ifndef _STLP_INTERNAL_LIMITS
#define _STLP_INTERNAL_LIMITS

#ifndef _STLP_CLIMITS
#  include <climits>
#endif

#ifndef _STLP_CFLOAT
#  include <cfloat>
#endif

#if defined (_STLP_HAS_WCHAR_T) && !defined (_STLP_INTERNAL_CWCHAR)
#  include <stl/_cwchar.h>
#endif

_STLP_BEGIN_NAMESPACE

enum float_round_style {
  round_indeterminate       = -1,
  round_toward_zero         =  0,
  round_to_nearest          =  1,
  round_toward_infinity     =  2,
  round_toward_neg_infinity =  3
};

enum float_denorm_style {
  denorm_indeterminate = -1,
  denorm_absent        =  0,
  denorm_present       =  1
};

_STLP_MOVE_TO_PRIV_NAMESPACE

// Base class for all specializations of numeric_limits.
template <class __number>
class _Numeric_limits_base {
public:

  static __number (_STLP_CALL min)() _STLP_NOTHROW { return __number(); }
  static __number (_STLP_CALL max)() _STLP_NOTHROW { return __number(); }

  _STLP_STATIC_CONSTANT(int, digits = 0);
  _STLP_STATIC_CONSTANT(int, digits10 = 0);
  _STLP_STATIC_CONSTANT(int, radix = 0);
  _STLP_STATIC_CONSTANT(int, min_exponent = 0);
  _STLP_STATIC_CONSTANT(int, min_exponent10 = 0);
  _STLP_STATIC_CONSTANT(int, max_exponent = 0);
  _STLP_STATIC_CONSTANT(int, max_exponent10 = 0);

  _STLP_STATIC_CONSTANT(float_denorm_style, has_denorm = denorm_absent);
  _STLP_STATIC_CONSTANT(float_round_style, round_style = round_toward_zero);

  _STLP_STATIC_CONSTANT(bool, is_specialized = false);
  _STLP_STATIC_CONSTANT(bool, is_signed  = false);
  _STLP_STATIC_CONSTANT(bool, is_integer = false);
  _STLP_STATIC_CONSTANT(bool, is_exact = false);
  _STLP_STATIC_CONSTANT(bool, has_infinity = false);
  _STLP_STATIC_CONSTANT(bool, has_quiet_NaN = false);
  _STLP_STATIC_CONSTANT(bool, has_signaling_NaN = false);
  _STLP_STATIC_CONSTANT(bool, has_denorm_loss = false);
  _STLP_STATIC_CONSTANT(bool, is_iec559 = false);
  _STLP_STATIC_CONSTANT(bool, is_bounded = false);
  _STLP_STATIC_CONSTANT(bool, is_modulo = false);
  _STLP_STATIC_CONSTANT(bool, traps = false);
  _STLP_STATIC_CONSTANT(bool, tinyness_before = false);

  static __number _STLP_CALL epsilon() _STLP_NOTHROW     { return __number(); }
  static __number _STLP_CALL round_error() _STLP_NOTHROW { return __number(); }

  static __number _STLP_CALL infinity() _STLP_NOTHROW      { return __number(); }
  static __number _STLP_CALL quiet_NaN() _STLP_NOTHROW     { return __number(); }
  static __number _STLP_CALL signaling_NaN() _STLP_NOTHROW { return __number(); }
  static __number _STLP_CALL denorm_min() _STLP_NOTHROW    { return __number(); }
};

// Base class for integers.

#ifdef _STLP_LIMITED_DEFAULT_TEMPLATES
#  ifdef _STLP_LONG_LONG
#    define _STLP_LIMITS_MIN_TYPE _STLP_LONG_LONG
#    define _STLP_LIMITS_MAX_TYPE unsigned _STLP_LONG_LONG
#  else
#    define _STLP_LIMITS_MIN_TYPE long
#    define _STLP_LIMITS_MAX_TYPE unsigned long
#  endif
#else
#  define _STLP_LIMITS_MIN_TYPE _Int
#  define _STLP_LIMITS_MAX_TYPE _Int
#endif /* _STLP_LIMITED_DEFAULT_TEMPLATES */

template <class _Int,
          _STLP_LIMITS_MIN_TYPE __imin,
          _STLP_LIMITS_MAX_TYPE __imax,
          int __idigits, bool __ismod>
class _Integer_limits : public _Numeric_limits_base<_Int> {
public:

  static _Int (_STLP_CALL min) () _STLP_NOTHROW { return (_Int)__imin; }
  static _Int (_STLP_CALL max) () _STLP_NOTHROW { return (_Int)__imax; }

  _STLP_STATIC_CONSTANT(int, digits = (__idigits < 0) ? ((int)((sizeof(_Int) * (CHAR_BIT))) - ((__imin == 0) ? 0 : 1)) : (__idigits));
  _STLP_STATIC_CONSTANT(int, digits10 = (digits * 301UL) / 1000);
  _STLP_STATIC_CONSTANT(int, radix = 2);
  _STLP_STATIC_CONSTANT(bool, is_specialized = true);
  _STLP_STATIC_CONSTANT(bool, is_signed = (__imin != 0));
  _STLP_STATIC_CONSTANT(bool, is_integer = true);
  _STLP_STATIC_CONSTANT(bool, is_exact = true);
  _STLP_STATIC_CONSTANT(bool, is_bounded = true);
  _STLP_STATIC_CONSTANT(bool, is_modulo = __ismod);
};

// Base class for floating-point numbers.
template <class __number,
         int __Digits, int __Digits10,
         int __MinExp, int __MaxExp,
         int __MinExp10, int __MaxExp10,
         bool __IsIEC559,
         float_denorm_style __DenormStyle,
         float_round_style __RoundStyle>
class _Floating_limits : public _Numeric_limits_base<__number> {
public:

  _STLP_STATIC_CONSTANT(int, digits = __Digits);
  _STLP_STATIC_CONSTANT(int, digits10 = __Digits10);
  _STLP_STATIC_CONSTANT(int, radix = FLT_RADIX);
  _STLP_STATIC_CONSTANT(int, min_exponent = __MinExp);
  _STLP_STATIC_CONSTANT(int, max_exponent = __MaxExp);
  _STLP_STATIC_CONSTANT(int, min_exponent10 = __MinExp10);
  _STLP_STATIC_CONSTANT(int, max_exponent10 = __MaxExp10);

  _STLP_STATIC_CONSTANT(float_denorm_style, has_denorm = __DenormStyle);
  _STLP_STATIC_CONSTANT(float_round_style, round_style = __RoundStyle);

  _STLP_STATIC_CONSTANT(bool, is_specialized = true);
  _STLP_STATIC_CONSTANT(bool, is_signed = true);

  _STLP_STATIC_CONSTANT(bool, has_infinity = true);
#if (!defined (_STLP_MSVC) || (_STLP_MSVC > 1300)) && \
    (!defined (__BORLANDC__) || (__BORLANDC__ >= 0x590)) && \
    (!defined (_CRAY) || defined (_CRAYIEEE))
  _STLP_STATIC_CONSTANT(bool, has_quiet_NaN = true);
  _STLP_STATIC_CONSTANT(bool, has_signaling_NaN = true);
#else
  _STLP_STATIC_CONSTANT(bool, has_quiet_NaN = false);
  _STLP_STATIC_CONSTANT(bool, has_signaling_NaN = false);
#endif

  _STLP_STATIC_CONSTANT(bool, is_iec559 = __IsIEC559 && has_infinity && has_quiet_NaN && has_signaling_NaN && (has_denorm == denorm_present));
  _STLP_STATIC_CONSTANT(bool, has_denorm_loss =  false);
  _STLP_STATIC_CONSTANT(bool, is_bounded = true);
  _STLP_STATIC_CONSTANT(bool, traps = true);
  _STLP_STATIC_CONSTANT(bool, tinyness_before = false);
};

_STLP_MOVE_TO_STD_NAMESPACE

// Class numeric_limits

// The unspecialized class.

template<class _Tp>
class numeric_limits : public _STLP_PRIV _Numeric_limits_base<_Tp> {};

// Specializations for all built-in integral types.

#if !defined (_STLP_NO_BOOL)
_STLP_TEMPLATE_NULL
class numeric_limits<bool>
  : public _STLP_PRIV _Integer_limits<bool, false, true, 1, false>
{};
#endif /* _STLP_NO_BOOL */

_STLP_TEMPLATE_NULL
class numeric_limits<char>
  : public _STLP_PRIV _Integer_limits<char, CHAR_MIN, CHAR_MAX, -1, true>
{};

#if !defined (_STLP_NO_SIGNED_BUILTINS)
_STLP_TEMPLATE_NULL
class numeric_limits<signed char>
  : public _STLP_PRIV _Integer_limits<signed char, SCHAR_MIN, SCHAR_MAX, -1, true>
{};
#endif

_STLP_TEMPLATE_NULL
class numeric_limits<unsigned char>
  : public _STLP_PRIV _Integer_limits<unsigned char, 0, UCHAR_MAX, -1, true>
{};

#if !(defined (_STLP_NO_WCHAR_T) || defined (_STLP_WCHAR_T_IS_USHORT))

_STLP_TEMPLATE_NULL
class numeric_limits<wchar_t>
  : public _STLP_PRIV _Integer_limits<wchar_t, WCHAR_MIN, WCHAR_MAX, -1, true>
{};

#endif

_STLP_TEMPLATE_NULL
class numeric_limits<short>
  : public _STLP_PRIV _Integer_limits<short, SHRT_MIN, SHRT_MAX, -1, true>
{};

_STLP_TEMPLATE_NULL
class numeric_limits<unsigned short>
  : public _STLP_PRIV _Integer_limits<unsigned short, 0, USHRT_MAX, -1, true>
{};

#if defined (__xlC__) && (__xlC__ == 0x500)
#  undef INT_MIN
#  define INT_MIN -2147483648
#endif

_STLP_TEMPLATE_NULL
class numeric_limits<int>
  : public _STLP_PRIV _Integer_limits<int, INT_MIN, INT_MAX, -1, true>
{};

_STLP_TEMPLATE_NULL
class numeric_limits<unsigned int>
  : public _STLP_PRIV _Integer_limits<unsigned int, 0, UINT_MAX, -1, true>
{};

_STLP_TEMPLATE_NULL
class numeric_limits<long>
  : public _STLP_PRIV _Integer_limits<long, LONG_MIN, LONG_MAX, -1, true>
{};

_STLP_TEMPLATE_NULL
class numeric_limits<unsigned long>
  : public _STLP_PRIV _Integer_limits<unsigned long, 0, ULONG_MAX, -1, true>
{};

#if defined (_STLP_LONG_LONG)

#  if defined (_STLP_MSVC) || defined (__BORLANDC__)
#    define LONGLONG_MAX     0x7fffffffffffffffi64