c_locale.cc

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// Wrapper for underlying C-language localization -*- C++ -*-

// Copyright (C) 2001, 2002, 2003, 2004, 2005
// 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 2, 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.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

//
// ISO C++ 14882: 22.8  Standard locale categories.
//

// Written by Benjamin Kosnik <[e-mail]>

#include <cerrno>  // For errno
#include <cmath>  // For isinf, finite, finitef, fabs
#include <cstdlib>  // For strof, strtold
#include <locale>

#ifdef _GLIBCXX_HAVE_IEEEFP_H
#include <ieeefp.h>
#endif

namespace std 
{
  // Specializations for all types used in num_get.
  template<>
    void
    __convert_to_v(const char* __s, float& __v, ios_base::iostate& __err, 
		   const __c_locale&) 	      
    {
      // Assumes __s formatted for "C" locale.
      errno = 0;
      char* __old = strdup(setlocale(LC_ALL, NULL));
      setlocale(LC_ALL, "C");
      char* __sanity;
#if defined(_GLIBCXX_HAVE_STRTOF)
      float __f = strtof(__s, &__sanity);
#else
      double __d = strtod(__s, &__sanity);
      float __f = static_cast<float>(__d);
#ifdef _GLIBCXX_HAVE_FINITEF
      if (!finitef (__f))
	errno = ERANGE;
#elif defined (_GLIBCXX_HAVE_FINITE)
      if (!finite (static_cast<double> (__f)))
	errno = ERANGE;
#elif defined (_GLIBCXX_HAVE_ISINF)
      if (isinf (static_cast<double> (__f)))
	errno = ERANGE;
#else
      if (fabs(__d) > numeric_limits<float>::max())
	errno = ERANGE;
#endif
#endif
      if (__sanity != __s && errno != ERANGE)
	__v = __f;
      else
	__err |= ios_base::failbit;
      setlocale(LC_ALL, __old);
      free(__old);
    }

  template<>
    void
    __convert_to_v(const char* __s, double& __v, ios_base::iostate& __err, 
		   const __c_locale&) 
    {
      // Assumes __s formatted for "C" locale.
      errno = 0;
      char* __old = strdup(setlocale(LC_ALL, NULL));
      setlocale(LC_ALL, "C");
      char* __sanity;
      double __d = strtod(__s, &__sanity);
      if (__sanity != __s && errno != ERANGE)
	__v = __d;
      else
	__err |= ios_base::failbit;
      setlocale(LC_ALL, __old);
      free(__old);
    }

  template<>
    void
    __convert_to_v(const char* __s, long double& __v, 
		   ios_base::iostate& __err, const __c_locale&) 
    {
      // Assumes __s formatted for "C" locale.
      errno = 0;
      char* __old = strdup(setlocale(LC_ALL, NULL));
      setlocale(LC_ALL, "C");
#if defined(_GLIBCXX_HAVE_STRTOLD)
      char* __sanity;
      long double __ld = strtold(__s, &__sanity);
      if (__sanity != __s && errno != ERANGE)
	__v = __ld;
#else
      typedef char_traits<char>::int_type int_type;
      long double __ld;
      int __p = sscanf(__s, "%Lf", &__ld);
      if (__p && static_cast<int_type>(__p) != char_traits<char>::eof()
	  && errno != ERANGE)
	__v = __ld;
#endif
      else
	__err |= ios_base::failbit;
      setlocale(LC_ALL, __old);
      free(__old);
    }

  void
  locale::facet::_S_create_c_locale(__c_locale& __cloc, const char* __s, 
				    __c_locale)
  {
    // Currently, the generic model only supports the "C" locale.
    // See http://gcc.gnu.org/ml/libstdc++/2003-02/msg00345.html
    __cloc = NULL;
    if (strcmp(__s, "C"))
      __throw_runtime_error(__N("locale::facet::_S_create_c_locale "
			    "name not valid"));
  }

  void
  locale::facet::_S_destroy_c_locale(__c_locale& __cloc)
  { __cloc = NULL; }

  __c_locale
  locale::facet::_S_clone_c_locale(__c_locale&)
  { return __c_locale(); }
} // namespace std

namespace __gnu_cxx
{
  const char* const category_names[6 + _GLIBCXX_NUM_CATEGORIES] =
    {
      "LC_CTYPE", 
      "LC_NUMERIC",
      "LC_TIME",   
      "LC_COLLATE", 
      "LC_MONETARY",
      "LC_MESSAGES"
    };
}  

namespace std
{
  const char* const* const locale::_S_categories = __gnu_cxx::category_names;
}  // namespace std