xref: /openbsd-src/gnu/lib/libstdc++/libstdc++/include/bits/locale_classes.h (revision 534d6ef73a061b07292185cee5cb8230994f382b)

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

// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
// 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// 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: 22.1  Locales
//

/** @file localefwd.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 */

#ifndef _CPP_BITS_LOCALE_CLASSES_H
#define _CPP_BITS_LOCALE_CLASSES_H	1

#pragma GCC system_header

#include <bits/localefwd.h>
#include <cstring>		// For strcmp.
#include <string>
#include <bits/atomicity.h>

namespace std
{
  class __locale_cache_base;
  template<typename _Facet> class __locale_cache;

  // 22.1.1 Class locale
  class locale
  {
  public:
    // Types:
    typedef unsigned int 	category;

    // Forward decls and friends:
    class facet;
    class id;
    class _Impl;

    friend class facet;
    friend class _Impl;

    template<typename _Facet>
      friend const _Facet&
      use_facet(const locale&);

    template<typename _Facet>
      friend bool
      has_facet(const locale&) throw();

    template<typename _Facet>
      friend const __locale_cache<_Facet>&
      __use_cache(const locale&);

    // Category values:
    // NB: Order must match _S_facet_categories definition in locale.cc
    static const category none		= 0;
    static const category ctype 	= 1L << 0;
    static const category numeric 	= 1L << 1;
    static const category collate  	= 1L << 2;
    static const category time 		= 1L << 3;
    static const category monetary 	= 1L << 4;
    static const category messages 	= 1L << 5;
    static const category all 		= (ctype | numeric | collate |
				 	   time  | monetary | messages);

    // Construct/copy/destroy:
    locale() throw();

    locale(const locale& __other) throw();

    explicit
    locale(const char* __s);

    locale(const locale& __base, const char* __s, category __cat);

    locale(const locale& __base, const locale& __add, category __cat);

    template<typename _Facet>
      locale(const locale& __other, _Facet* __f);

    ~locale() throw();

    const locale&
    operator=(const locale& __other) throw();

    template<typename _Facet>
      locale
      combine(const locale& __other) const;

    // Locale operations:
    string
    name() const;

    bool
    operator==(const locale& __other) const throw ();

    inline bool
    operator!=(const locale& __other) const throw ()
    { return !(this->operator==(__other));  }

    template<typename _Char, typename _Traits, typename _Alloc>
      bool
      operator()(const basic_string<_Char, _Traits, _Alloc>& __s1,
		 const basic_string<_Char, _Traits, _Alloc>& __s2) const;

    // Global locale objects:
    static locale
    global(const locale&);

    static const locale&
    classic();

  private:
    // The (shared) implementation
    _Impl* 		_M_impl;

    // The "C" reference locale
    static _Impl* 	_S_classic;

    // Current global locale
    static _Impl* 	_S_global;

    // Number of standard categories. For C++, these categories are
    // collate, ctype, monetary, numeric, time, and messages. These
    // directly correspond to ISO C99 macros LC_COLLATE, LC_CTYPE,
    // LC_MONETARY, LC_NUMERIC, and LC_TIME. In addition, POSIX (IEEE
    // 1003.1-2001) specifies LC_MESSAGES.
    static const size_t	_S_categories_size = 6;

    // In addition to the standard categories, the underlying
    // operating system is allowed to define extra LC_*
    // macros. For GNU systems, the following are also valid:
    // LC_PAPER, LC_NAME, LC_ADDRESS, LC_TELEPHONE, LC_MEASUREMENT,
    // and LC_IDENTIFICATION.
    static const size_t	_S_extra_categories_size = _GLIBCPP_NUM_CATEGORIES;

    // Names of underlying locale categories.
    // NB: locale::global() has to know how to modify all the
    // underlying categories, not just the ones required by the C++
    // standard.
    static const char* 	_S_categories[_S_categories_size
				      + _S_extra_categories_size];

    explicit
    locale(_Impl*) throw();

    static inline void
    _S_initialize()
    {
      if (!_S_classic)
	classic();
    }

    static category
    _S_normalize_category(category);

    void
    _M_coalesce(const locale& __base, const locale& __add, category __cat);
  };


  // Implementation object for locale
  class locale::_Impl
  {
  public:
    // Friends.
    friend class locale;
    friend class locale::facet;

    template<typename _Facet>
      friend const _Facet&
      use_facet(const locale&);

    template<typename _Facet>
      friend bool
      has_facet(const locale&) throw();

    template<typename _Facet>
      friend const __locale_cache<_Facet>&
      __use_cache(const locale&);

  private:
    // Data Members.
    _Atomic_word			_M_references;
    facet** 				_M_facets;
    size_t 				_M_facets_size;

    char* 				_M_names[_S_categories_size
						 + _S_extra_categories_size];
    static const locale::id* const 	_S_id_ctype[];
    static const locale::id* const 	_S_id_numeric[];
    static const locale::id* const 	_S_id_collate[];
    static const locale::id* const 	_S_id_time[];
    static const locale::id* const 	_S_id_monetary[];
    static const locale::id* const 	_S_id_messages[];
    static const locale::id* const* const _S_facet_categories[];

    inline void
    _M_add_reference() throw()
    { __atomic_add(&_M_references, 1); }

    inline void
    _M_remove_reference() throw()
    {
      if (__exchange_and_add(&_M_references, -1) == 1)
	{
	  try
	    { delete this; }
	  catch(...)
	    { }
	}
    }

    _Impl(const _Impl&, size_t);
    _Impl(const char*, size_t);
    _Impl(facet**, size_t, bool);

   ~_Impl() throw();

    _Impl(const _Impl&);  // Not defined.

    void
    operator=(const _Impl&);  // Not defined.

    inline bool
    _M_check_same_name()
    {
      bool __ret = true;
      for (size_t __i = 0;
	   __ret && __i < _S_categories_size + _S_extra_categories_size - 1;
	   ++__i)
	__ret &= (strcmp(_M_names[__i], _M_names[__i + 1]) == 0);
      return __ret;
    }

    void
    _M_replace_categories(const _Impl*, category);

    void
    _M_replace_category(const _Impl*, const locale::id* const*);

    void
    _M_replace_facet(const _Impl*, const locale::id*);

    void
    _M_install_facet(const locale::id*, facet*);

    template<typename _Facet>
      inline void
      _M_init_facet(_Facet* __facet)
      { _M_install_facet(&_Facet::id, __facet);  }

    // Retrieve the cache at __index.  0 is returned if the cache is
    // missing.  Cache is actually located at __index +
    // _M_facets_size.  __index must be < _M_facets_size.
    inline __locale_cache_base*
      _M_get_cache(size_t __index)
      {
	return (__locale_cache_base*)_M_facets[__index + _M_facets_size];
      }

    // Save the supplied cache at __id.  Assumes _M_get_cache has been
    // called.
    void
    _M_install_cache(__locale_cache_base* __cache, int __id)
    {
      _M_facets[__id + _M_facets_size] =
	reinterpret_cast<locale::facet*>(__cache);
    }

  };

  template<typename _Facet>
    locale::locale(const locale& __other, _Facet* __f)
    {
      _M_impl = new _Impl(*__other._M_impl, 1);

      char* _M_tmp_names[_S_categories_size + _S_extra_categories_size];
      size_t __i = 0;
      try
	{
	  for (; __i < _S_categories_size
		       + _S_extra_categories_size; ++__i)
	    {
	      _M_tmp_names[__i] = new char[2];
	      strlcpy(_M_tmp_names[__i], "*", 2);
	    }
	  _M_impl->_M_install_facet(&_Facet::id, __f);
	}
      catch(...)
	{
	  _M_impl->_M_remove_reference();
	  for (size_t __j = 0; __j < __i; ++__j)
	    delete [] _M_tmp_names[__j];
	  __throw_exception_again;
	}

      for (size_t __k = 0; __k < _S_categories_size
	                         + _S_extra_categories_size; ++__k)
	{
	  delete [] _M_impl->_M_names[__k];
	  _M_impl->_M_names[__k] = _M_tmp_names[__k];
	}
    }


  // 22.1.1.1.2  Class locale::facet
  class locale::facet
  {
  private:
    friend class locale;
    friend class locale::_Impl;

    _Atomic_word 			_M_references;

  protected:
    // Contains data from the underlying "C" library for the classic locale.
    static __c_locale		     	_S_c_locale;

    // String literal for the name of the classic locale.
    static char				_S_c_name[2];

    explicit
    facet(size_t __refs = 0) throw();

    virtual
    ~facet();

    static void
    _S_create_c_locale(__c_locale& __cloc, const char* __s,
		       __c_locale __old = 0);

    static __c_locale
    _S_clone_c_locale(__c_locale& __cloc);

    static void
    _S_destroy_c_locale(__c_locale& __cloc);

  private:
    void
    _M_add_reference() throw();

    void
    _M_remove_reference() throw();

    facet(const facet&);  // Not defined.

    void
    operator=(const facet&);  // Not defined.
  };


  // 22.1.1.1.3 Class locale::id
  class locale::id
  {
  private:
    friend class locale;
    friend class locale::_Impl;
    template<typename _Facet>
      friend const _Facet&
      use_facet(const locale&);
    template<typename _Facet>
      friend bool
      has_facet(const locale&) throw ();

    // NB: There is no accessor for _M_index because it may be used
    // before the constructor is run; the effect of calling a member
    // function (even an inline) would be undefined.
    mutable size_t 		_M_index;

    // Last id number assigned.
    static _Atomic_word 	_S_highwater;

    void
    operator=(const id&);  // Not defined.

    id(const id&);  // Not defined.

  public:
    // NB: This class is always a static data member, and thus can be
    // counted on to be zero-initialized.
    id();

    inline size_t
    _M_id() const
    {
      if (!_M_index)
	_M_index = 1 + __exchange_and_add(&_S_highwater, 1);
      return _M_index - 1;
    }
  };
} // namespace std

#endif