_num_get.c

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/*
 * Copyright (c) 1999
 * 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.
 *
 */
#ifndef _STLP_NUM_GET_C
#define _STLP_NUM_GET_C

#ifndef _STLP_INTERNAL_NUM_GET_H
#  include <stl/_num_get.h>
#endif

#ifndef _STLP_INTERNAL_LIMITS
#  include <stl/_limits.h>
#endif

_STLP_BEGIN_NAMESPACE

_STLP_MOVE_TO_PRIV_NAMESPACE

_STLP_DECLSPEC unsigned char _STLP_CALL __digit_val_table(unsigned);
_STLP_DECLSPEC const char* _STLP_CALL __narrow_atoms();

// __do_get_integer, __do_get_float and its helper functions.

inline bool _STLP_CALL __get_fdigit(char __c, const char*)
{ return __c >= '0' && __c <= '9'; }

inline bool _STLP_CALL __get_fdigit_or_sep(char& __c, char __sep, const char *__digits) {
  if (__c == __sep) {
    __c = ',' ;
    return true ;
  }
  else
    return  __get_fdigit(__c, __digits);
}

inline int _STLP_CALL
__get_digit_from_table(unsigned __index)
{ return (__index > 127 ? 0xFF : __digit_val_table(__index)); }

template <class _InputIter, class _CharT>
int
__get_base_or_zero(_InputIter& __in_ite, _InputIter& __end,
                   ios_base::fmtflags __flags, const ctype<_CharT>& __c_type) {
  _CharT __atoms[5];
  __c_type.widen(__narrow_atoms(), __narrow_atoms() + 5, __atoms);

  bool __negative = false;
  _CharT __c = *__in_ite;

  if (__c == __atoms[1] /* __xminus_char */ ) {
    __negative = true;
    ++__in_ite;
  }
  else if (__c == __atoms[0] /* __xplus_char */ )
    ++__in_ite;

  int __base;
  int __valid_zero = 0;

  ios_base::fmtflags __basefield = __flags & ios_base::basefield;

  switch (__basefield) {
  case ios_base::oct:
    __base = 8;
    break;
  case ios_base::dec:
    __base = 10;
    break;
  case ios_base::hex:
    __base = 16;
    if (__in_ite != __end && *__in_ite == __atoms[2] /* __zero_char */ ) {
      ++__in_ite;
      if (__in_ite != __end &&
          (*__in_ite == __atoms[3] /* __x_char */ || *__in_ite == __atoms[4] /* __X_char */ ))
        ++__in_ite;
      else
        __valid_zero = 1; // That zero is valid by itself.
    }
    break;
  default:
    if (__in_ite != __end && *__in_ite == __atoms[2] /* __zero_char */ ) {
      ++__in_ite;
      if (__in_ite != __end &&
          (*__in_ite == __atoms[3] /* __x_char */ || *__in_ite == __atoms[4] /* __X_char */ )) {
        ++__in_ite;
        __base = 16;
      }
      else
        {
          __base = 8;
          __valid_zero = 1; // That zero is still valid by itself.
        }
    }
    else
      __base = 10;
    break;
  }
  return (__base << 2) | ((int)__negative << 1) | __valid_zero;
}


template <class _InputIter, class _Integer, class _CharT>
bool _STLP_CALL
__get_integer(_InputIter& __first, _InputIter& __last,
              int __base, _Integer& __val,
              int __got, bool __is_negative, _CharT __separator, const string& __grouping, const __true_type& /*_IsSigned*/) {
  bool __ovflow = false;
  _Integer __result = 0;
  bool __is_group = !__grouping.empty();
  char __group_sizes[64];
  char __current_group_size = 0;
  char* __group_sizes_end = __group_sizes;

  _Integer __over_base = (numeric_limits<_Integer>::min)() / __STATIC_CAST(_Integer, __base);

   for ( ; __first != __last ; ++__first) {

     const _CharT __c = *__first;

     if (__is_group && __c == __separator) {
       *__group_sizes_end++ = __current_group_size;
       __current_group_size = 0;
       continue;
     }

     int __n = __get_digit_from_table(__c);

     if (__n >= __base)
       break;

     ++__got;
     ++__current_group_size;

     if (__result < __over_base)
       __ovflow = true;  // don't need to keep accumulating
     else {
       _Integer __next = __STATIC_CAST(_Integer, __base * __result - __n);
       if (__result != 0)
         __ovflow = __ovflow || __next >= __result;
       __result = __next;
     }
   }

   if (__is_group && __group_sizes_end != __group_sizes) {
     *__group_sizes_end++ = __current_group_size;
   }

   // fbp : added to not modify value if nothing was read
   if (__got > 0) {
       __val = __ovflow ? __is_negative ? (numeric_limits<_Integer>::min)()
                                        : (numeric_limits<_Integer>::max)()
                        : __is_negative ? __result
                                        : __STATIC_CAST(_Integer, -__result);
   }
  // overflow is being treated as failure
  return ((__got > 0) && !__ovflow) &&
          (__is_group == 0 ||
           __valid_grouping(__group_sizes, __group_sizes_end,
                            __grouping.data(), __grouping.data()+ __grouping.size()));
}

template <class _InputIter, class _Integer, class _CharT>
bool _STLP_CALL
__get_integer(_InputIter& __first, _InputIter& __last,
              int __base, _Integer& __val,
              int __got, bool __is_negative, _CharT __separator, const string& __grouping, const __false_type& /*_IsSigned*/) {
  bool __ovflow = false;
  _Integer __result = 0;
  bool __is_group = !__grouping.empty();
  char __group_sizes[64];
  char __current_group_size = 0;
  char* __group_sizes_end = __group_sizes;

  _Integer  __over_base = (numeric_limits<_Integer>::max)() / __STATIC_CAST(_Integer, __base);

  for ( ; __first != __last ; ++__first) {

    const _CharT __c = *__first;

    if (__is_group && __c == __separator) {
      *__group_sizes_end++ = __current_group_size;
      __current_group_size = 0;
      continue;
    }

    int __n = __get_digit_from_table(__c);

    if (__n >= __base)
      break;

    ++__got;
    ++__current_group_size;

    if (__result > __over_base)
      __ovflow = true;  //don't need to keep accumulating
    else {
      _Integer __next = __STATIC_CAST(_Integer, __base * __result + __n);
      if (__result != 0)
        __ovflow = __ovflow || __next <= __result;
        __result = __next;
      }
  }

  if (__is_group && __group_sizes_end != __group_sizes) {
      *__group_sizes_end++ = __current_group_size;
  }

  // fbp : added to not modify value if nothing was read
  if (__got > 0) {
      __val = __ovflow ? (numeric_limits<_Integer>::max)()
                       : (__is_negative ? __STATIC_CAST(_Integer, -__result)
                                        : __result);
  }

  // overflow is being treated as failure
  return ((__got > 0) && !__ovflow) &&
          (__is_group == 0 ||
           __valid_grouping(__group_sizes, __group_sizes_end,
                            __grouping.data(), __grouping.data()+ __grouping.size()));
}


template <class _InputIter, class _Integer, class _CharT>
bool _STLP_CALL
__get_decimal_integer(_InputIter& __first, _InputIter& __last, _Integer& __val, _CharT* /*dummy*/) {
  string __grp;
  //Here there is no grouping so separator is not important, we just pass the default character.
  return __get_integer(__first, __last, 10, __val, 0, false, _CharT() /*separator*/, __grp, __false_type());
}

template <class _InputIter, class _Integer, class _CharT>
_InputIter _STLP_CALL
__do_get_integer(_InputIter& __in_ite, _InputIter& __end, ios_base& __str,
                 ios_base::iostate& __err, _Integer& __val, _CharT* /*__pc*/) {
  locale __loc = __str.getloc();
  const ctype<_CharT>& __ctype = use_facet<ctype<_CharT> >(__loc);

#if defined (__HP_aCC) && (__HP_aCC == 1)
  bool _IsSigned = !((_Integer)(-1) > 0);
#else
  typedef typename __bool2type<numeric_limits<_Integer>::is_signed>::_Ret _IsSigned;
#endif

  const int __base_or_zero = __get_base_or_zero(__in_ite, __end, __str.flags(), __ctype);
  int  __got = __base_or_zero & 1;

  bool __result;

  if (__in_ite == __end) {      // We may have already read a 0.  If so,

    if (__got > 0) {       // the result is 0 even if we're at eof.
      __val = 0;
      __result = true;
    }
    else
      __result = false;
  }
  else {
    const numpunct<_CharT>& __np = use_facet<numpunct<_CharT> >(__loc);
    const bool __negative = (__base_or_zero & 2) != 0;
    const int __base = __base_or_zero >> 2;

#if defined (__HP_aCC) && (__HP_aCC == 1)
    if (_IsSigned)
      __result = __get_integer(__in_ite, __end, __base,  __val, __got, __negative, __np.thousands_sep(), __np.grouping(), __true_type() );
    else
      __result = __get_integer(__in_ite, __end, __base,  __val, __got, __negative, __np.thousands_sep(), __np.grouping(), __false_type() );
#else
    __result = __get_integer(__in_ite, __end, __base,  __val, __got, __negative, __np.thousands_sep(), __np.grouping(), _IsSigned());
# endif
  }

  __err = __STATIC_CAST(ios_base::iostate, __result ? ios_base::goodbit : ios_base::failbit);

  if (__in_ite == __end)
    __err |= ios_base::eofbit;
  return __in_ite;
}

// __read_float and its helper functions.
template <class _InputIter, class _CharT>
_InputIter  _STLP_CALL
__copy_sign(_InputIter __first, _InputIter __last, __iostring& __v,
            _CharT __xplus, _CharT __xminus) {
  if (__first != __last) {
    _CharT __c = *__first;
    if (__c == __xplus)
      ++__first;
    else if (__c == __xminus) {
      __v.push_back('-');
      ++__first;
    }
  }
  return __first;
}


template <class _InputIter, class _CharT>