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

// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006

// 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: 22.1  Locales

//

/** @file locale_classes.h

 *  This is an internal header file, included by other library headers.

 *  You should not attempt to use it directly.

 */

#ifndef _LOCALE_CLASSES_H

#define _LOCALE_CLASSES_H 1

#pragma GCC system_header

#include <bits/localefwd.h>

#include <cstring>              // For strcmp.

#include <string>

#include <bits/atomicity.h>

#include <bits/gthr.h>

namespace std

{

  // 22.1.1 Class locale

  /**

   *  @brief  Container class for localization functionality.

   *

   *  The locale class is first a class wrapper for C library locales.  It is

   *  also an extensible container for user-defined localization.  A locale is

   *  a collection of facets that implement various localization features such

   *  as money, time, and number printing.

   *

   *  Constructing C++ locales does not change the C library locale.

   *

   *  This library supports efficient construction and copying of locales

   *  through a reference counting implementation of the locale class.

  */

  class locale

  {

  public:

    // Types:

    /// Definition of locale::category.

    typedef int category;

    // Forward decls and friends:

    class facet;

    class id;

    class _Impl;

    friend class facet;

    friend class _Impl;

    template<typename _Facet>

      friend bool

      has_facet(const locale&) throw();

    template<typename _Facet>

      friend const _Facet&

      use_facet(const locale&);

    template<typename _Cache>

      friend struct __use_cache;

    //@{

    /**

     *  @brief  Category values.

     *

     *  The standard category values are none, ctype, numeric, collate, time,

     *  monetary, and messages.  They form a bitmask that supports union and

     *  intersection.  The category all is the union of these values.

     *

     *  @if maint

     *  NB: Order must match _S_facet_categories definition in locale.cc

     *  @endif

    */

    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:

    /**

     *  @brief  Default constructor.

     *

     *  Constructs a copy of the global locale.  If no locale has been

     *  explicitly set, this is the "C" locale.

    */

    locale() throw();

    /**

     *  @brief  Copy constructor.

     *

     *  Constructs a copy of @a other.

     *

     *  @param  other  The locale to copy.

    */

    locale(const locale& __other) throw();

    /**

     *  @brief  Named locale constructor.

     *

     *  Constructs a copy of the named C library locale.

     *

     *  @param  s  Name of the locale to construct.

     *  @throw  std::runtime_error if s is null or an undefined locale.

    */

    explicit

    locale(const char* __s);

    /**

     *  @brief  Construct locale with facets from another locale.

     *

     *  Constructs a copy of the locale @a base.  The facets specified by @a

     *  cat are replaced with those from the locale named by @a s.  If base is

     *  named, this locale instance will also be named.

     *

     *  @param  base  The locale to copy.

     *  @param  s  Name of the locale to use facets from.

     *  @param  cat  Set of categories defining the facets to use from s.

     *  @throw  std::runtime_error if s is null or an undefined locale.

    */

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

    /**

     *  @brief  Construct locale with facets from another locale.

     *

     *  Constructs a copy of the locale @a base.  The facets specified by @a

     *  cat are replaced with those from the locale @a add.  If @a base and @a

     *  add are named, this locale instance will also be named.

     *

     *  @param  base  The locale to copy.

     *  @param  add  The locale to use facets from.

     *  @param  cat  Set of categories defining the facets to use from add.

    */

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

    /**

     *  @brief  Construct locale with another facet.

     *

     *  Constructs a copy of the locale @a other.  The facet @f is added to

     *  @other, replacing an existing facet of type Facet if there is one.  If

     *  @f is null, this locale is a copy of @a other.

     *

     *  @param  other  The locale to copy.

     *  @param  f  The facet to add in.

    */

    template<typename _Facet>

      locale(const locale& __other, _Facet* __f);

    /// Locale destructor.

    ~locale() throw();

    /**

     *  @brief  Assignment operator.

     *

     *  Set this locale to be a copy of @a other.

     *

     *  @param  other  The locale to copy.

     *  @return  A reference to this locale.

    */

    const locale&

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

    /**

     *  @brief  Construct locale with another facet.

     *

     *  Constructs and returns a new copy of this locale.  Adds or replaces an

     *  existing facet of type Facet from the locale @a other into the new

     *  locale.

     *

     *  @param  Facet  The facet type to copy from other

     *  @param  other  The locale to copy from.

     *  @return  Newly constructed locale.

     *  @throw  std::runtime_error if other has no facet of type Facet.

    */

    template<typename _Facet>

      locale

      combine(const locale& __other) const;

    // Locale operations:

    /**

     *  @brief  Return locale name.

     *  @return  Locale name or "*" if unnamed.

    */

    string

    name() const;

    /**

     *  @brief  Locale equality.

     *

     *  @param  other  The locale to compare against.

     *  @return  True if other and this refer to the same locale instance, are

     *           copies, or have the same name.  False otherwise.

    */

    bool

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

    /**

     *  @brief  Locale inequality.

     *

     *  @param  other  The locale to compare against.

     *  @return  ! (*this == other)

    */

    inline bool

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

    { return !(this->operator==(__other));  }

    /**

     *  @brief  Compare two strings according to collate.

     *

     *  Template operator to compare two strings using the compare function of

     *  the collate facet in this locale.  One use is to provide the locale to

     *  the sort function.  For example, a vector v of strings could be sorted

     *  according to locale loc by doing:

     *  @code

     *  std::sort(v.begin(), v.end(), loc);

     *  @endcode

     *

     *  @param  s1  First string to compare.

     *  @param  s2  Second string to compare.

     *  @return  True if collate<Char> facet compares s1 < s2, else false.

    */

    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:

    /**

     *  @brief  Set global locale

     *

     *  This function sets the global locale to the argument and returns a

     *  copy of the previous global locale.  If the argument has a name, it

     *  will also call std::setlocale(LC_ALL, loc.name()).

     *

     *  @param  locale  The new locale to make global.

     *  @return  Copy of the old global locale.

    */

    static locale

    global(const locale&);

    /**

     *  @brief  Return reference to the "C" 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;

    // 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* const* const _S_categories;

    // 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.

    // 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.

    enum { _S_categories_size = 6 + _GLIBCXX_NUM_CATEGORIES };

#ifdef __GTHREADS

    static __gthread_once_t _S_once;

#endif

    explicit

    locale(_Impl*) throw();

    static void

    _S_initialize();

    static void

    _S_initialize_once();

    static category

    _S_normalize_category(category);

    void

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

  };

  // 22.1.1.1.2  Class locale::facet

  /**

   *  @brief  Localization functionality base class.

   *

   *  The facet class is the base class for a localization feature, such as

   *  money, time, and number printing.  It provides common support for facets

   *  and reference management.

   *

   *  Facets may not be copied or assigned.

  */

  class locale::facet

  {

  private:

    friend class locale;

    friend class locale::_Impl;

    mutable _Atomic_word                _M_refcount;

    // 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 const char                   _S_c_name[2];

#ifdef __GTHREADS

    static __gthread_once_t             _S_once;

#endif

    static void

    _S_initialize_once();

  protected:

    /**

     *  @brief  Facet constructor.

     *

     *  This is the constructor provided by the standard.  If refs is 0, the

     *  facet is destroyed when the last referencing locale is destroyed.

     *  Otherwise the facet will never be destroyed.

     *

     *  @param refs  The initial value for reference count.

    */

    explicit

    facet(size_t __refs = 0) throw() : _M_refcount(__refs ? 1 : 0)

    { }

    /// Facet destructor.

    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);

    // Returns data from the underlying "C" library data for the

    // classic locale.

    static __c_locale

    _S_get_c_locale();

    static const char*

    _S_get_c_name();

  private:

    inline void

    _M_add_reference() const throw()

    { __gnu_cxx::__atomic_add(&_M_refcount, 1); }

    inline void

    _M_remove_reference() const throw()

    {

      if (__gnu_cxx::__exchange_and_add(&_M_refcount, -1) == 1)

        {

          try

            { delete this; }

          catch (...)

            { }

        }

    }

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

    facet&

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

  };

  // 22.1.1.1.3 Class locale::id

  /**

   *  @brief  Facet ID class.

   *

   *  The ID class provides facets with an index used to identify them.

   *  Every facet class must define a public static member locale::id, or be

   *  derived from a facet that provides this member, otherwise the facet

   *  cannot be used in a locale.  The locale::id ensures that each class

   *  type gets a unique identifier.

  */

  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_refcount;

    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.

    /// Constructor.

    id() { }

    size_t

    _M_id() const;

  };

  // Implementation object for locale.

  class locale::_Impl

  {

  public:

    // Friends.

    friend class locale;

    friend class locale::facet;

    template<typename _Facet>

      friend bool

      has_facet(const locale&) throw();

    template<typename _Facet>

      friend const _Facet&

      use_facet(const locale&);

    template<typename _Cache>

      friend struct __use_cache;

  private:

    // Data Members.

    _Atomic_word                        _M_refcount;

    const facet**                       _M_facets;

    size_t                              _M_facets_size;

    const facet**                       _M_caches;

    char**                              _M_names;

    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()

    { __gnu_cxx::__atomic_add(&_M_refcount, 1); }

    inline void

    _M_remove_reference() throw()

    {

      if (__gnu_cxx::__exchange_and_add(&_M_refcount, -1) == 1)

        {

          try

            { delete this; }

          catch(...)

            { }

        }

    }

    _Impl(const _Impl&, size_t);

    _Impl(const char*, size_t);

    _Impl(size_t) throw();

   ~_Impl() throw();

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

    void

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

    inline bool

    _M_check_same_name()

    {

      bool __ret = true;

      if (_M_names[1])

        // We must actually compare all the _M_names: can be all equal!

        for (size_t __i = 0; __ret && __i < _S_categories_size - 1; ++__i)

          __ret = std::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*, const facet*);

    template<typename _Facet>

      inline void

      _M_init_facet(_Facet* __facet)

      { _M_install_facet(&_Facet::id, __facet); }

    void

    _M_install_cache(const facet*, size_t);

  };

  template<typename _Facet>

    locale::locale(const locale& __other, _Facet* __f)

    {

      _M_impl = new _Impl(*__other._M_impl, 1);

      try

        { _M_impl->_M_install_facet(&_Facet::id, __f); }

      catch(...)

        {

          _M_impl->_M_remove_reference();

          __throw_exception_again;

        }

      delete [] _M_impl->_M_names[0];

      _M_impl->_M_names[0] = 0;   // Unnamed.

    }

} // namespace std

#endif