locale_facets.tcc

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// Locale support -*- C++ -*-

// Copyright (C) 1997-2017 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/** @file bits/locale_facets.tcc
 *  This is an internal header file, included by other library headers.
 *  Do not attempt to use it directly. @headername{locale}
 */

#ifndef _LOCALE_FACETS_TCC
#define _LOCALE_FACETS_TCC 1

#pragma GCC system_header

namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

  // Routine to access a cache for the facet.  If the cache didn't
  // exist before, it gets constructed on the fly.
  template<typename _Facet>
    struct __use_cache
    {
      const _Facet*
      operator() (const locale& __loc) const;
    };

  // Specializations.
  template<typename _CharT>
    struct __use_cache<__numpunct_cache<_CharT> >
    {
      const __numpunct_cache<_CharT>*
      operator() (const locale& __loc) const
      {
        const size_t __i = numpunct<_CharT>::id._M_id();
        const locale::facet** __caches = __loc._M_impl->_M_caches;
        if (!__caches[__i])
          {
            __numpunct_cache<_CharT>* __tmp = 0;
            __try
              {
                __tmp = new __numpunct_cache<_CharT>;
                __tmp->_M_cache(__loc);
              }
            __catch(...)
              {
                delete __tmp;
                __throw_exception_again;
              }
            __loc._M_impl->_M_install_cache(__tmp, __i);
          }
        return static_cast<const __numpunct_cache<_CharT>*>(__caches[__i]);
      }
    };

  template<typename _CharT>
    void
    __numpunct_cache<_CharT>::_M_cache(const locale& __loc)
    {
      const numpunct<_CharT>& __np = use_facet<numpunct<_CharT> >(__loc);

      char* __grouping = 0;
      _CharT* __truename = 0;
      _CharT* __falsename = 0;
      __try
        {
          const string& __g = __np.grouping();
          _M_grouping_size = __g.size();
          __grouping = new char[_M_grouping_size];
          __g.copy(__grouping, _M_grouping_size);
          _M_use_grouping = (_M_grouping_size
                             && static_cast<signed char>(__grouping[0]) > 0
                             && (__grouping[0]
                                 != __gnu_cxx::__numeric_traits<char>::__max));

          const basic_string<_CharT>& __tn = __np.truename();
          _M_truename_size = __tn.size();
          __truename = new _CharT[_M_truename_size];
          __tn.copy(__truename, _M_truename_size);

          const basic_string<_CharT>& __fn = __np.falsename();
          _M_falsename_size = __fn.size();
          __falsename = new _CharT[_M_falsename_size];
          __fn.copy(__falsename, _M_falsename_size);

          _M_decimal_point = __np.decimal_point();
          _M_thousands_sep = __np.thousands_sep();

          const ctype<_CharT>& __ct = use_facet<ctype<_CharT> >(__loc);
          __ct.widen(__num_base::_S_atoms_out,
                     __num_base::_S_atoms_out
                     + __num_base::_S_oend, _M_atoms_out);
          __ct.widen(__num_base::_S_atoms_in,
                     __num_base::_S_atoms_in
                     + __num_base::_S_iend, _M_atoms_in);

          _M_grouping = __grouping;
          _M_truename = __truename;
          _M_falsename = __falsename;
          _M_allocated = true;
        }
      __catch(...)
        {
          delete [] __grouping;
          delete [] __truename;
          delete [] __falsename;
          __throw_exception_again;
        }
    }

  // Used by both numeric and monetary facets.
  // Check to make sure that the __grouping_tmp string constructed in
  // money_get or num_get matches the canonical grouping for a given
  // locale.
  // __grouping_tmp is parsed L to R
  // 1,222,444 == __grouping_tmp of "\1\3\3"
  // __grouping is parsed R to L
  // 1,222,444 == __grouping of "\3" == "\3\3\3"
  _GLIBCXX_PURE bool
  __verify_grouping(const char* __grouping, size_t __grouping_size,
                    const string& __grouping_tmp) throw ();

_GLIBCXX_BEGIN_NAMESPACE_LDBL

  template<typename _CharT, typename _InIter>
    _GLIBCXX_DEFAULT_ABI_TAG
    _InIter
    num_get<_CharT, _InIter>::
    _M_extract_float(_InIter __beg, _InIter __end, ios_base& __io,
                     ios_base::iostate& __err, string& __xtrc) const
    {
      typedef char_traits<_CharT>                       __traits_type;
      typedef __numpunct_cache<_CharT>                  __cache_type;
      __use_cache<__cache_type> __uc;
      const locale& __loc = __io._M_getloc();
      const __cache_type* __lc = __uc(__loc);
      const _CharT* __lit = __lc->_M_atoms_in;
      char_type __c = char_type();

      // True if __beg becomes equal to __end.
      bool __testeof = __beg == __end;

      // First check for sign.
      if (!__testeof)
        {
          __c = *__beg;
          const bool __plus = __c == __lit[__num_base::_S_iplus];
          if ((__plus || __c == __lit[__num_base::_S_iminus])
              && !(__lc->_M_use_grouping && __c == __lc->_M_thousands_sep)
              && !(__c == __lc->_M_decimal_point))
            {
              __xtrc += __plus ? '+' : '-';
              if (++__beg != __end)
                __c = *__beg;
              else
                __testeof = true;
            }
        }

      // Next, look for leading zeros.
      bool __found_mantissa = false;
      int __sep_pos = 0;
      while (!__testeof)
        {
          if ((__lc->_M_use_grouping && __c == __lc->_M_thousands_sep)
              || __c == __lc->_M_decimal_point)
            break;
          else if (__c == __lit[__num_base::_S_izero])
            {
              if (!__found_mantissa)
                {
                  __xtrc += '0';
                  __found_mantissa = true;
                }
              ++__sep_pos;

              if (++__beg != __end)
                __c = *__beg;
              else
                __testeof = true;
            }
          else
            break;
        }

      // Only need acceptable digits for floating point numbers.
      bool __found_dec = false;
      bool __found_sci = false;
      string __found_grouping;
      if (__lc->_M_use_grouping)
        __found_grouping.reserve(32);
      const char_type* __lit_zero = __lit + __num_base::_S_izero;

      if (!__lc->_M_allocated)
        // "C" locale
        while (!__testeof)
          {
            const int __digit = _M_find(__lit_zero, 10, __c);
            if (__digit != -1)
              {
                __xtrc += '0' + __digit;
                __found_mantissa = true;
              }
            else if (__c == __lc->_M_decimal_point
                     && !__found_dec && !__found_sci)
              {
                __xtrc += '.';
                __found_dec = true;
              }
            else if ((__c == __lit[__num_base::_S_ie] 
                      || __c == __lit[__num_base::_S_iE])
                     && !__found_sci && __found_mantissa)
              {
                // Scientific notation.
                __xtrc += 'e';
                __found_sci = true;
                
                // Remove optional plus or minus sign, if they exist.
                if (++__beg != __end)
                  {
                    __c = *__beg;
                    const bool __plus = __c == __lit[__num_base::_S_iplus];
                    if (__plus || __c == __lit[__num_base::_S_iminus])
                      __xtrc += __plus ? '+' : '-';
                    else
                      continue;
                  }
                else
                  {
                    __testeof = true;
                    break;
                  }
              }
            else
              break;

            if (++__beg != __end)
              __c = *__beg;
            else
              __testeof = true;
          }
      else
        while (!__testeof)
          {
            // According to 22.2.2.1.2, p8-9, first look for thousands_sep
            // and decimal_point.
            if (__lc->_M_use_grouping && __c == __lc->_M_thousands_sep)
              {
                if (!__found_dec && !__found_sci)
                  {
                    // NB: Thousands separator at the beginning of a string
                    // is a no-no, as is two consecutive thousands separators.
                    if (__sep_pos)
                      {
                        __found_grouping += static_cast<char>(__sep_pos);
                        __sep_pos = 0;
                      }
                    else
                      {
                        // NB: __convert_to_v will not assign __v and will
                        // set the failbit.
                        __xtrc.clear();
                        break;
                      }
                  }
                else
                  break;
              }
            else if (__c == __lc->_M_decimal_point)
              {
                if (!__found_dec && !__found_sci)
                  {
                    // If no grouping chars are seen, no grouping check
                    // is applied. Therefore __found_grouping is adjusted
                    // only if decimal_point comes after some thousands_sep.
                    if (__found_grouping.size())
                      __found_grouping += static_cast<char>(__sep_pos);
                    __xtrc += '.';
                    __found_dec = true;
                  }
                else
                  break;
              }
            else
              {
                const char_type* __q =
                  __traits_type::find(__lit_zero, 10, __c);
                if (__q)
                  {
                    __xtrc += '0' + (__q - __lit_zero);
                    __found_mantissa = true;
                    ++__sep_pos;
                  }
                else if ((__c == __lit[__num_base::_S_ie] 
                          || __c == __lit[__num_base::_S_iE])
                         && !__found_sci && __found_mantissa)
                  {
                    // Scientific notation.
                    if (__found_grouping.size() && !__found_dec)
                      __found_grouping += static_cast<char>(__sep_pos);
                    __xtrc += 'e';
                    __found_sci = true;
                    
                    // Remove optional plus or minus sign, if they exist.
                    if (++__beg != __end)
                      {
                        __c = *__beg;
                        const bool __plus = __c == __lit[__num_base::_S_iplus];
                        if ((__plus || __c == __lit[__num_base::_S_iminus])
                            && !(__lc->_M_use_grouping
                                 && __c == __lc->_M_thousands_sep)
                            && !(__c == __lc->_M_decimal_point))
                      __xtrc += __plus ? '+' : '-';
                        else
                          continue;
                      }
                    else
                      {
                        __testeof = true;
                        break;
                      }
                  }
                else
                  break;
              }
            
            if (++__beg != __end)
              __c = *__beg;
            else
              __testeof = true;
          }

      // Digit grouping is checked. If grouping and found_grouping don't
      // match, then get very very upset, and set failbit.
      if (__found_grouping.size())
        {
          // Add the ending grouping if a decimal or 'e'/'E' wasn't found.
          if (!__found_dec && !__found_sci)
            __found_grouping += static_cast<char>(__sep_pos);

          if (!std::__verify_grouping(__lc->_M_grouping, 
                                      __lc->_M_grouping_size,
                                      __found_grouping))
            __err = ios_base::failbit;
        }

      return __beg;
    }

  template<typename _CharT, typename _InIter>
    template<typename _ValueT>
      _GLIBCXX_DEFAULT_ABI_TAG
      _InIter
      num_get<_CharT, _InIter>::
      _M_extract_int(_InIter __beg, _InIter __end, ios_base& __io,
                     ios_base::iostate& __err, _ValueT& __v) const
      {
        typedef char_traits<_CharT>                          __traits_type;
        using __gnu_cxx::__add_unsigned;
        typedef typename __add_unsigned<_ValueT>::__type __unsigned_type;
        typedef __numpunct_cache<_CharT>                     __cache_type;
        __use_cache<__cache_type> __uc;
        const locale& __loc = __io._M_getloc();
        const __cache_type* __lc = __uc(__loc);
        const _CharT* __lit = __lc->_M_atoms_in;
        char_type __c = char_type();

        // NB: Iff __basefield == 0, __base can change based on contents.
        const ios_base::fmtflags __basefield = __io.flags()
                                               & ios_base::basefield;
        const bool __oct = __basefield == ios_base::oct;
        int __base = __oct ? 8 : (__basefield == ios_base::hex ? 16 : 10);

        // True if __beg becomes equal to __end.
        bool __testeof = __beg == __end;

        // First check for sign.
        bool __negative = false;
        if (!__testeof)
          {
            __c = *__beg;
            __negative = __c == __lit[__num_base::_S_iminus];
            if ((__negative || __c == __lit[__num_base::_S_iplus])
                && !(__lc->_M_use_grouping && __c == __lc->_M_thousands_sep)
                && !(__c == __lc->_M_decimal_point))
              {
                if (++__beg != __end)
                  __c = *__beg;
                else
                  __testeof = true;
              }
          }

        // Next, look for leading zeros and check required digits
        // for base formats.
        bool __found_zero = false;
        int __sep_pos = 0;
        while (!__testeof)
          {
            if ((__lc->_M_use_grouping && __c == __lc->_M_thousands_sep)
                || __c == __lc->_M_decimal_point)
              break;
            else if (__c == __lit[__num_base::_S_izero] 
                     && (!__found_zero || __base == 10))
              {
                __found_zero = true;
                ++__sep_pos;
                if (__basefield == 0)
                  __base = 8;
                if (__base == 8)
                  __sep_pos = 0;
              }
            else if (__found_zero
                     && (__c == __lit[__num_base::_S_ix]
                         || __c == __lit[__num_base::_S_iX]))
              {
                if (__basefield == 0)
                  __base = 16;
                if (__base == 16)
                  {
                    __found_zero = false;
                    __sep_pos = 0;
                  }
                else
                  break;
              }
            else
              break;

            if (++__beg != __end)
              {
                __c = *__beg;
                if (!__found_zero)
                  break;
              }
            else
              __testeof = true;
          }
        
        // At this point, base is determined. If not hex, only allow
        // base digits as valid input.
        const size_t __len = (__base == 16 ? __num_base::_S_iend
                              - __num_base::_S_izero : __base);

        // Extract.
        string __found_grouping;
        if (__lc->_M_use_grouping)
          __found_grouping.reserve(32);
        bool __testfail = false;
        bool __testoverflow = false;
        const __unsigned_type __max =
          (__negative && __gnu_cxx::__numeric_traits<_ValueT>::__is_signed)
          ? -__gnu_cxx::__numeric_traits<_ValueT>::__min
          : __gnu_cxx::__numeric_traits<_ValueT>::__max;
        const __unsigned_type __smax = __max / __base;
        __unsigned_type __result = 0;
        int __digit = 0;
        const char_type* __lit_zero = __lit + __num_base::_S_izero;

        if (!__lc->_M_allocated)
          // "C" locale
          while (!__testeof)
            {
              __digit = _M_find(__lit_zero, __len, __c);
              if (__digit == -1)
                break;
              
              if (__result > __smax)
                __testoverflow = true;
              else
                {
                  __result *= __base;
                  __testoverflow |= __result > __max - __digit;
                  __result += __digit;
                  ++__sep_pos;
                }
              
              if (++__beg != __end)
                __c = *__beg;
              else
                __testeof = true;
            }
        else
          while (!__testeof)
            {
              // According to 22.2.2.1.2, p8-9, first look for thousands_sep
              // and decimal_point.
              if (__lc->_M_use_grouping && __c == __lc->_M_thousands_sep)
                {
                  // NB: Thousands separator at the beginning of a string
                  // is a no-no, as is two consecutive thousands separators.
                  if (__sep_pos)
                    {
                      __found_grouping += static_cast<char>(__sep_pos);
                      __sep_pos = 0;
                    }
                  else
                    {
                      __testfail = true;
                      break;
                    }
                }
              else if (__c == __lc->_M_decimal_point)
                break;
              else
                {
                  const char_type* __q =
                    __traits_type::find(__lit_zero, __len, __c);
                  if (!__q)
                    break;
                  
                  __digit = __q - __lit_zero;
                  if (__digit > 15)
                    __digit -= 6;
                  if (__result > __smax)
                    __testoverflow = true;
                  else
                    {
                      __result *= __base;
                      __testoverflow |= __result > __max - __digit;
                      __result += __digit;
                      ++__sep_pos;
                    }
                }
              
              if (++__beg != __end)
                __c = *__beg;
              else
                __testeof = true;
            }
        
        // Digit grouping is checked. If grouping and found_grouping don't
        // match, then get very very upset, and set failbit.
        if (__found_grouping.size())
          {
            // Add the ending grouping.
            __found_grouping += static_cast<char>(__sep_pos);

            if (!std::__verify_grouping(__lc->_M_grouping,
                                        __lc->_M_grouping_size,
                                        __found_grouping))
              __err = ios_base::failbit;
          }

        // _GLIBCXX_RESOLVE_LIB_DEFECTS
        // 23. Num_get overflow result.
        if ((!__sep_pos && !__found_zero && !__found_grouping.size())
            || __testfail)
          {
            __v = 0;
            __err = ios_base::failbit;
          }
        else if (__testoverflow)
          {
            if (__negative
                && __gnu_cxx::__numeric_traits<_ValueT>::__is_signed)
              __v = __gnu_cxx::__numeric_traits<_ValueT>::__min;
            else
              __v = __gnu_cxx::__numeric_traits<_ValueT>::__max;
            __err = ios_base::failbit;
          }
        else
          __v = __negative ? -__result : __result;

        if (__testeof)
          __err |= ios_base::eofbit;
        return __beg;
      }

  // _GLIBCXX_RESOLVE_LIB_DEFECTS
  // 17.  Bad bool parsing
  template<typename _CharT, typename _InIter>
    _InIter
    num_get<_CharT, _InIter>::
    do_get(iter_type __beg, iter_type __end, ios_base& __io,
           ios_base::iostate& __err, bool& __v) const
    {
      if (!(__io.flags() & ios_base::boolalpha))
        {
          // Parse bool values as long.
          // NB: We can't just call do_get(long) here, as it might
          // refer to a derived class.
          long __l = -1;
          __beg = _M_extract_int(__beg, __end, __io, __err, __l);
          if (__l == 0 || __l == 1)
            __v = bool(__l);
          else
            {
              // _GLIBCXX_RESOLVE_LIB_DEFECTS
              // 23. Num_get overflow result.
              __v = true;
              __err = ios_base::failbit;
              if (__beg == __end)
                __err |= ios_base::eofbit;
            }
        }
      else
        {
          // Parse bool values as alphanumeric.
          typedef __numpunct_cache<_CharT>  __cache_type;
          __use_cache<__cache_type> __uc;
          const locale& __loc = __io._M_getloc();
          const __cache_type* __lc = __uc(__loc);

          bool __testf = true;
          bool __testt = true;
          bool __donef = __lc->_M_falsename_size == 0;
          bool __donet = __lc->_M_truename_size == 0;
          bool __testeof = false;
          size_t __n = 0;
          while (!__donef || !__donet)
            {
              if (__beg == __end)
                {
                  __testeof = true;
                  break;
                }

              const char_type __c = *__beg;

              if (!__donef)
                __testf = __c == __lc->_M_falsename[__n];

              if (!__testf && __donet)
                break;

              if (!__donet)
                __testt = __c == __lc->_M_truename[__n];

              if (!__testt && __donef)
                break;

              if (!__testt && !__testf)
                break;

              ++__n;
              ++__beg;

              __donef = !__testf || __n >= __lc->_M_falsename_size;
              __donet = !__testt || __n >= __lc->_M_truename_size;
            }
          if (__testf && __n == __lc->_M_falsename_size && __n)
            {
              __v = false;
              if (__testt && __n == __lc->_M_truename_size)
                __err = ios_base::failbit;
              else
                __err = __testeof ? ios_base::eofbit : ios_base::goodbit;
            }
          else if (__testt && __n == __lc->_M_truename_size && __n)
            {
              __v = true;
              __err = __testeof ? ios_base::eofbit : ios_base::goodbit;
            }
          else
            {
              // _GLIBCXX_RESOLVE_LIB_DEFECTS
              // 23. Num_get overflow result.
              __v = false;
              __err = ios_base::failbit;
              if (__testeof)
                __err |= ios_base::eofbit;
            }
        }
      return __beg;
    }

  template<typename _CharT, typename _InIter>
    _InIter
    num_get<_CharT, _InIter>::
    do_get(iter_type __beg, iter_type __end, ios_base& __io,
           ios_base::iostate& __err, float& __v) const
    {
      string __xtrc;
      __xtrc.reserve(32);
      __beg = _M_extract_float(__beg, __end, __io, __err, __xtrc);
      std::__convert_to_v(__xtrc.c_str(), __v, __err, _S_get_c_locale());
      if (__beg == __end)
        __err |= ios_base::eofbit;
      return __beg;
    }

  template<typename _CharT, typename _InIter>
    _InIter
    num_get<_CharT, _InIter>::
    do_get(iter_type __beg, iter_type __end, ios_base& __io,
           ios_base::iostate& __err, double& __v) const
    {
      string __xtrc;
      __xtrc.reserve(32);
      __beg = _M_extract_float(__beg, __end, __io, __err, __xtrc);
      std::__convert_to_v(__xtrc.c_str(), __v, __err, _S_get_c_locale());
      if (__beg == __end)
        __err |= ios_base::eofbit;
      return __beg;
    }

#if defined _GLIBCXX_LONG_DOUBLE_COMPAT && defined __LONG_DOUBLE_128__
  template<typename _CharT, typename _InIter>
    _InIter
    num_get<_CharT, _InIter>::
    __do_get(iter_type __beg, iter_type __end, ios_base& __io,
             ios_base::iostate& __err, double& __v) const
    {
      string __xtrc;
      __xtrc.reserve(32);
      __beg = _M_extract_float(__beg, __end, __io, __err, __xtrc);
      std::__convert_to_v(__xtrc.c_str(), __v, __err, _S_get_c_locale());
      if (__beg == __end)
        __err |= ios_base::eofbit;
      return __beg;
    }
#endif

  template<typename _CharT, typename _InIter>
    _InIter
    num_get<_CharT, _InIter>::
    do_get(iter_type __beg, iter_type __end, ios_base& __io,
           ios_base::iostate& __err, long double& __v) const
    {
      string __xtrc;
      __xtrc.reserve(32);
      __beg = _M_extract_float(__beg, __end, __io, __err, __xtrc);
      std::__convert_to_v(__xtrc.c_str(), __v, __err, _S_get_c_locale());
      if (__beg == __end)
        __err |= ios_base::eofbit;
      return __beg;
    }

  template<typename _CharT, typename _InIter>
    _InIter
    num_get<_CharT, _InIter>::
    do_get(iter_type __beg, iter_type __end, ios_base& __io,
           ios_base::iostate& __err, void*& __v) const
    {
      // Prepare for hex formatted input.
      typedef ios_base::fmtflags        fmtflags;
      const fmtflags __fmt = __io.flags();
      __io.flags((__fmt & ~ios_base::basefield) | ios_base::hex);

      typedef __gnu_cxx::__conditional_type<(sizeof(void*)
                                             <= sizeof(unsigned long)),
        unsigned long, unsigned long long>::__type _UIntPtrType;       

      _UIntPtrType __ul;
      __beg = _M_extract_int(__beg, __end, __io, __err, __ul);

      // Reset from hex formatted input.
      __io.flags(__fmt);

      __v = reinterpret_cast<void*>(__ul);
      return __beg;
    }

  // For use by integer and floating-point types after they have been
  // converted into a char_type string.
  template<typename _CharT, typename _OutIter>
    void
    num_put<_CharT, _OutIter>::
    _M_pad(_CharT __fill, streamsize __w, ios_base& __io,
           _CharT* __new, const _CharT* __cs, int& __len) const
    {
      // [22.2.2.2.2] Stage 3.
      // If necessary, pad.
      __pad<_CharT, char_traits<_CharT> >::_S_pad(__io, __fill, __new,
                                                  __cs, __w, __len);
      __len = static_cast<int>(__w);
    }

_GLIBCXX_END_NAMESPACE_LDBL

  template<typename _CharT, typename _ValueT>
    int
    __int_to_char(_CharT* __bufend, _ValueT __v, const _CharT* __lit,
                  ios_base::fmtflags __flags, bool __dec)
    {
      _CharT* __buf = __bufend;
      if (__builtin_expect(__dec, true))
        {
          // Decimal.
          do
            {
              *--__buf = __lit[(__v % 10) + __num_base::_S_odigits];
              __v /= 10;
            }
          while (__v != 0);
        }
      else if ((__flags & ios_base::basefield) == ios_base::oct)
        {
          // Octal.
          do
            {
              *--__buf = __lit[(__v & 0x7) + __num_base::_S_odigits];
              __v >>= 3;
            }
          while (__v != 0);
        }
      else
        {
          // Hex.
          const bool __uppercase = __flags & ios_base::uppercase;
          const int __case_offset = __uppercase ? __num_base::_S_oudigits
                                                : __num_base::_S_odigits;
          do
            {
              *--__buf = __lit[(__v & 0xf) + __case_offset];
              __v >>= 4;
            }
          while (__v != 0);
        }
      return __bufend - __buf;
    }

_GLIBCXX_BEGIN_NAMESPACE_LDBL

  template<typename _CharT, typename _OutIter>
    void
    num_put<_CharT, _OutIter>::
    _M_group_int(const char* __grouping, size_t __grouping_size, _CharT __sep,
                 ios_base&, _CharT* __new, _CharT* __cs, int& __len) const
    {
      _CharT* __p = std::__add_grouping(__new, __sep, __grouping,
                                        __grouping_size, __cs, __cs + __len);
      __len = __p - __new;
    }
  
  template<typename _CharT, typename _OutIter>
    template<typename _ValueT>
      _OutIter
      num_put<_CharT, _OutIter>::
      _M_insert_int(_OutIter __s, ios_base& __io, _CharT __fill,
                    _ValueT __v) const
      {
        using __gnu_cxx::__add_unsigned;
        typedef typename __add_unsigned<_ValueT>::__type __unsigned_type;
        typedef __numpunct_cache<_CharT>                     __cache_type;
        __use_cache<__cache_type> __uc;
        const locale& __loc = __io._M_getloc();
        const __cache_type* __lc = __uc(__loc);
        const _CharT* __lit = __lc->_M_atoms_out;
        const ios_base::fmtflags __flags = __io.flags();

        // Long enough to hold hex, dec, and octal representations.
        const int __ilen = 5 * sizeof(_ValueT);
        _CharT* __cs = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
                                                             * __ilen));

        // [22.2.2.2.2] Stage 1, numeric conversion to character.
        // Result is returned right-justified in the buffer.
        const ios_base::fmtflags __basefield = __flags & ios_base::basefield;
        const bool __dec = (__basefield != ios_base::oct
                            && __basefield != ios_base::hex);
        const __unsigned_type __u = ((__v > 0 || !__dec)
                                     ? __unsigned_type(__v)
                                     : -__unsigned_type(__v));
        int __len = __int_to_char(__cs + __ilen, __u, __lit, __flags, __dec);
        __cs += __ilen - __len;

        // Add grouping, if necessary.
        if (__lc->_M_use_grouping)
          {
            // Grouping can add (almost) as many separators as the number
            // of digits + space is reserved for numeric base or sign.
            _CharT* __cs2 = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
                                                                  * (__len + 1)
                                                                  * 2));
            _M_group_int(__lc->_M_grouping, __lc->_M_grouping_size,
                         __lc->_M_thousands_sep, __io, __cs2 + 2, __cs, __len);
            __cs = __cs2 + 2;
          }

        // Complete Stage 1, prepend numeric base or sign.
        if (__builtin_expect(__dec, true))
          {
            // Decimal.
            if (__v >= 0)
              {
                if (bool(__flags & ios_base::showpos)
                    && __gnu_cxx::__numeric_traits<_ValueT>::__is_signed)
                  *--__cs = __lit[__num_base::_S_oplus], ++__len;
              }
            else
              *--__cs = __lit[__num_base::_S_ominus], ++__len;
          }
        else if (bool(__flags & ios_base::showbase) && __v)
          {
            if (__basefield == ios_base::oct)
              *--__cs = __lit[__num_base::_S_odigits], ++__len;
            else
              {
                // 'x' or 'X'
                const bool __uppercase = __flags & ios_base::uppercase;
                *--__cs = __lit[__num_base::_S_ox + __uppercase];
                // '0'
                *--__cs = __lit[__num_base::_S_odigits];
                __len += 2;
              }
          }

        // Pad.
        const streamsize __w = __io.width();
        if (__w > static_cast<streamsize>(__len))
          {
            _CharT* __cs3 = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
                                                                  * __w));
            _M_pad(__fill, __w, __io, __cs3, __cs, __len);
            __cs = __cs3;
          }
        __io.width(0);

        // [22.2.2.2.2] Stage 4.
        // Write resulting, fully-formatted string to output iterator.
        return std::__write(__s, __cs, __len);
      }

  template<typename _CharT, typename _OutIter>
    void
    num_put<_CharT, _OutIter>::
    _M_group_float(const char* __grouping, size_t __grouping_size,
                   _CharT __sep, const _CharT* __p, _CharT* __new,
                   _CharT* __cs, int& __len) const
    {
      // _GLIBCXX_RESOLVE_LIB_DEFECTS
      // 282. What types does numpunct grouping refer to?
      // Add grouping, if necessary.
      const int __declen = __p ? __p - __cs : __len;
      _CharT* __p2 = std::__add_grouping(__new, __sep, __grouping,
                                         __grouping_size,
                                         __cs, __cs + __declen);

      // Tack on decimal part.
      int __newlen = __p2 - __new;
      if (__p)
        {
          char_traits<_CharT>::copy(__p2, __p, __len - __declen);
          __newlen += __len - __declen;
        }
      __len = __newlen;
    }

  // The following code uses vsnprintf (or vsprintf(), when
  // _GLIBCXX_USE_C99_STDIO is not defined) to convert floating point
  // values for insertion into a stream.  An optimization would be to
  // replace them with code that works directly on a wide buffer and
  // then use __pad to do the padding.  It would be good to replace
  // them anyway to gain back the efficiency that C++ provides by
  // knowing up front the type of the values to insert.  Also, sprintf
  // is dangerous since may lead to accidental buffer overruns.  This
  // implementation follows the C++ standard fairly directly as
  // outlined in 22.2.2.2 [lib.locale.num.put]
  template<typename _CharT, typename _OutIter>
    template<typename _ValueT>
      _OutIter
      num_put<_CharT, _OutIter>::
      _M_insert_float(_OutIter __s, ios_base& __io, _CharT __fill, char __mod,
                       _ValueT __v) const
      {
        typedef __numpunct_cache<_CharT>                __cache_type;
        __use_cache<__cache_type> __uc;
        const locale& __loc = __io._M_getloc();
        const __cache_type* __lc = __uc(__loc);

        // Use default precision if out of range.
        const streamsize __prec = __io.precision() < 0 ? 6 : __io.precision();

        const int __max_digits =
          __gnu_cxx::__numeric_traits<_ValueT>::__digits10;

        // [22.2.2.2.2] Stage 1, numeric conversion to character.
        int __len;
        // Long enough for the max format spec.
        char __fbuf[16];
        __num_base::_S_format_float(__io, __fbuf, __mod);

#if _GLIBCXX_USE_C99_STDIO
        // Precision is always used except for hexfloat format.
        const bool __use_prec =
          (__io.flags() & ios_base::floatfield) != ios_base::floatfield;

        // First try a buffer perhaps big enough (most probably sufficient
        // for non-ios_base::fixed outputs)
        int __cs_size = __max_digits * 3;
        char* __cs = static_cast<char*>(__builtin_alloca(__cs_size));
        if (__use_prec)
          __len = std::__convert_from_v(_S_get_c_locale(), __cs, __cs_size,
                                        __fbuf, __prec, __v);
        else
          __len = std::__convert_from_v(_S_get_c_locale(), __cs, __cs_size,
                                        __fbuf, __v);

        // If the buffer was not large enough, try again with the correct size.
        if (__len >= __cs_size)
          {
            __cs_size = __len + 1;
            __cs = static_cast<char*>(__builtin_alloca(__cs_size));
            if (__use_prec)
              __len = std::__convert_from_v(_S_get_c_locale(), __cs, __cs_size,
                                            __fbuf, __prec, __v);
            else
              __len = std::__convert_from_v(_S_get_c_locale(), __cs, __cs_size,
                                            __fbuf, __v);
          }
#else
        // Consider the possibility of long ios_base::fixed outputs
        const bool __fixed = __io.flags() & ios_base::fixed;
        const int __max_exp =
          __gnu_cxx::__numeric_traits<_ValueT>::__max_exponent10;

        // The size of the output string is computed as follows.
        // ios_base::fixed outputs may need up to __max_exp + 1 chars
        // for the integer part + __prec chars for the fractional part
        // + 3 chars for sign, decimal point, '\0'. On the other hand,
        // for non-fixed outputs __max_digits * 2 + __prec chars are
        // largely sufficient.
        const int __cs_size = __fixed ? __max_exp + __prec + 4
                                      : __max_digits * 2 + __prec;
        char* __cs = static_cast<char*>(__builtin_alloca(__cs_size));
        __len = std::__convert_from_v(_S_get_c_locale(), __cs, 0, __fbuf, 
                                      __prec, __v);
#endif

        // [22.2.2.2.2] Stage 2, convert to char_type, using correct
        // numpunct.decimal_point() values for '.' and adding grouping.
        const ctype<_CharT>& __ctype = use_facet<ctype<_CharT> >(__loc);
        
        _CharT* __ws = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
                                                             * __len));
        __ctype.widen(__cs, __cs + __len, __ws);
        
        // Replace decimal point.
        _CharT* __wp = 0;
        const char* __p = char_traits<char>::find(__cs, __len, '.');
        if (__p)
          {
            __wp = __ws + (__p - __cs);
            *__wp = __lc->_M_decimal_point;
          }
        
        // Add grouping, if necessary.
        // N.B. Make sure to not group things like 2e20, i.e., no decimal
        // point, scientific notation.
        if (__lc->_M_use_grouping
            && (__wp || __len < 3 || (__cs[1] <= '9' && __cs[2] <= '9'
                                      && __cs[1] >= '0' && __cs[2] >= '0')))
          {
            // Grouping can add (almost) as many separators as the
            // number of digits, but no more.
            _CharT* __ws2 = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
                                                                  * __len * 2));
            
            streamsize __off = 0;
            if (__cs[0] == '-' || __cs[0] == '+')
              {
                __off = 1;
                __ws2[0] = __ws[0];
                __len -= 1;
              }
            
            _M_group_float(__lc->_M_grouping, __lc->_M_grouping_size,
                           __lc->_M_thousands_sep, __wp, __ws2 + __off,
                           __ws + __off, __len);
            __len += __off;
            
            __ws = __ws2;
          }

        // Pad.
        const streamsize __w = __io.width();
        if (__w > static_cast<streamsize>(__len))
          {
            _CharT* __ws3 = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
                                                                  * __w));
            _M_pad(__fill, __w, __io, __ws3, __ws, __len);
            __ws = __ws3;
          }
        __io.width(0);
        
        // [22.2.2.2.2] Stage 4.
        // Write resulting, fully-formatted string to output iterator.
        return std::__write(__s, __ws, __len);
      }
  
  template<typename _CharT, typename _OutIter>
    _OutIter
    num_put<_CharT, _OutIter>::
    do_put(iter_type __s, ios_base& __io, char_type __fill, bool __v) const
    {
      const ios_base::fmtflags __flags = __io.flags();
      if ((__flags & ios_base::boolalpha) == 0)
        {
          const long __l = __v;
          __s = _M_insert_int(__s, __io, __fill, __l);
        }
      else
        {
          typedef __numpunct_cache<_CharT>              __cache_type;
          __use_cache<__cache_type> __uc;
          const locale& __loc = __io._M_getloc();
          const __cache_type* __lc = __uc(__loc);

          const _CharT* __name = __v ? __lc->_M_truename
                                     : __lc->_M_falsename;
          int __len = __v ? __lc->_M_truename_size
                          : __lc->_M_falsename_size;

          const streamsize __w = __io.width();
          if (__w > static_cast<streamsize>(__len))
            {
              const streamsize __plen = __w - __len;
              _CharT* __ps
                = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
                                                        * __plen));

              char_traits<_CharT>::assign(__ps, __plen, __fill);
              __io.width(0);

              if ((__flags & ios_base::adjustfield) == ios_base::left)
                {
                  __s = std::__write(__s, __name, __len);
                  __s = std::__write(__s, __ps, __plen);
                }
              else
                {
                  __s = std::__write(__s, __ps, __plen);
                  __s = std::__write(__s, __name, __len);
                }
              return __s;
            }
          __io.width(0);
          __s = std::__write(__s, __name, __len);
        }
      return __s;
    }

  template<typename _CharT, typename _OutIter>
    _OutIter
    num_put<_CharT, _OutIter>::
    do_put(iter_type __s, ios_base& __io, char_type __fill, double __v) const
    { return _M_insert_float(__s, __io, __fill, char(), __v); }

#if defined _GLIBCXX_LONG_DOUBLE_COMPAT && defined __LONG_DOUBLE_128__
  template<typename _CharT, typename _OutIter>
    _OutIter
    num_put<_CharT, _OutIter>::
    __do_put(iter_type __s, ios_base& __io, char_type __fill, double __v) const
    { return _M_insert_float(__s, __io, __fill, char(), __v); }
#endif

  template<typename _CharT, typename _OutIter>
    _OutIter
    num_put<_CharT, _OutIter>::
    do_put(iter_type __s, ios_base& __io, char_type __fill,
           long double __v) const
    { return _M_insert_float(__s, __io, __fill, 'L', __v); }

  template<typename _CharT, typename _OutIter>
    _OutIter
    num_put<_CharT, _OutIter>::
    do_put(iter_type __s, ios_base& __io, char_type __fill,
           const void* __v) const
    {
      const ios_base::fmtflags __flags = __io.flags();
      const ios_base::fmtflags __fmt = ~(ios_base::basefield
                                         | ios_base::uppercase);
      __io.flags((__flags & __fmt) | (ios_base::hex | ios_base::showbase));

      typedef __gnu_cxx::__conditional_type<(sizeof(const void*)
                                             <= sizeof(unsigned long)),
        unsigned long, unsigned long long>::__type _UIntPtrType;       

      __s = _M_insert_int(__s, __io, __fill,
                          reinterpret_cast<_UIntPtrType>(__v));
      __io.flags(__flags);
      return __s;
    }

_GLIBCXX_END_NAMESPACE_LDBL

  // Construct correctly padded string, as per 22.2.2.2.2
  // Assumes
  // __newlen > __oldlen
  // __news is allocated for __newlen size

  // NB: Of the two parameters, _CharT can be deduced from the
  // function arguments. The other (_Traits) has to be explicitly specified.
  template<typename _CharT, typename _Traits>
    void
    __pad<_CharT, _Traits>::_S_pad(ios_base& __io, _CharT __fill,
                                   _CharT* __news, const _CharT* __olds,
                                   streamsize __newlen, streamsize __oldlen)
    {
      const size_t __plen = static_cast<size_t>(__newlen - __oldlen);
      const ios_base::fmtflags __adjust = __io.flags() & ios_base::adjustfield;

      // Padding last.
      if (__adjust == ios_base::left)
        {
          _Traits::copy(__news, __olds, __oldlen);
          _Traits::assign(__news + __oldlen, __plen, __fill);
          return;
        }

      size_t __mod = 0;
      if (__adjust == ios_base::internal)
        {
          // Pad after the sign, if there is one.
          // Pad after 0[xX], if there is one.
          // Who came up with these rules, anyway? Jeeze.
          const locale& __loc = __io._M_getloc();
          const ctype<_CharT>& __ctype = use_facet<ctype<_CharT> >(__loc);

          if (__ctype.widen('-') == __olds[0]
              || __ctype.widen('+') == __olds[0])
            {
              __news[0] = __olds[0];
              __mod = 1;
              ++__news;
            }
          else if (__ctype.widen('0') == __olds[0]
                   && __oldlen > 1
                   && (__ctype.widen('x') == __olds[1]
                       || __ctype.widen('X') == __olds[1]))
            {
              __news[0] = __olds[0];
              __news[1] = __olds[1];
              __mod = 2;
              __news += 2;
            }
          // else Padding first.
        }
      _Traits::assign(__news, __plen, __fill);
      _Traits::copy(__news + __plen, __olds + __mod, __oldlen - __mod);
    }

  template<typename _CharT>
    _CharT*
    __add_grouping(_CharT* __s, _CharT __sep,
                   const char* __gbeg, size_t __gsize,
                   const _CharT* __first, const _CharT* __last)
    {
      size_t __idx = 0;
      size_t __ctr = 0;

      while (__last - __first > __gbeg[__idx]
             && static_cast<signed char>(__gbeg[__idx]) > 0
             && __gbeg[__idx] != __gnu_cxx::__numeric_traits<char>::__max)
        {
          __last -= __gbeg[__idx];
          __idx < __gsize - 1 ? ++__idx : ++__ctr;
        }

      while (__first != __last)
        *__s++ = *__first++;

      while (__ctr--)
        {
          *__s++ = __sep;         
          for (char __i = __gbeg[__idx]; __i > 0; --__i)
            *__s++ = *__first++;
        }

      while (__idx--)
        {
          *__s++ = __sep;         
          for (char __i = __gbeg[__idx]; __i > 0; --__i)
            *__s++ = *__first++;
        }

      return __s;
    }

  // Inhibit implicit instantiations for required instantiations,
  // which are defined via explicit instantiations elsewhere.
#if _GLIBCXX_EXTERN_TEMPLATE
  extern template class _GLIBCXX_NAMESPACE_CXX11 numpunct<char>;
  extern template class _GLIBCXX_NAMESPACE_CXX11 numpunct_byname<char>;
  extern template class _GLIBCXX_NAMESPACE_LDBL num_get<char>;
  extern template class _GLIBCXX_NAMESPACE_LDBL num_put<char>;
  extern template class ctype_byname<char>;

  extern template
    const ctype<char>&
    use_facet<ctype<char> >(const locale&);

  extern template
    const numpunct<char>&
    use_facet<numpunct<char> >(const locale&);

  extern template
    const num_put<char>&
    use_facet<num_put<char> >(const locale&);

  extern template
    const num_get<char>&
    use_facet<num_get<char> >(const locale&);

  extern template
    bool
    has_facet<ctype<char> >(const locale&);

  extern template
    bool
    has_facet<numpunct<char> >(const locale&);

  extern template
    bool
    has_facet<num_put<char> >(const locale&);

  extern template
    bool
    has_facet<num_get<char> >(const locale&);

#ifdef _GLIBCXX_USE_WCHAR_T
  extern template class _GLIBCXX_NAMESPACE_CXX11 numpunct<wchar_t>;
  extern template class _GLIBCXX_NAMESPACE_CXX11 numpunct_byname<wchar_t>;
  extern template class _GLIBCXX_NAMESPACE_LDBL num_get<wchar_t>;
  extern template class _GLIBCXX_NAMESPACE_LDBL num_put<wchar_t>;
  extern template class ctype_byname<wchar_t>;

  extern template
    const ctype<wchar_t>&
    use_facet<ctype<wchar_t> >(const locale&);

  extern template
    const numpunct<wchar_t>&
    use_facet<numpunct<wchar_t> >(const locale&);

  extern template
    const num_put<wchar_t>&
    use_facet<num_put<wchar_t> >(const locale&);

  extern template
    const num_get<wchar_t>&
    use_facet<num_get<wchar_t> >(const locale&);

 extern template
    bool
    has_facet<ctype<wchar_t> >(const locale&);

  extern template
    bool
    has_facet<numpunct<wchar_t> >(const locale&);

  extern template
    bool
    has_facet<num_put<wchar_t> >(const locale&);

  extern template
    bool
    has_facet<num_get<wchar_t> >(const locale&);
#endif
#endif

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace

#endif