Viewing file:  locale_classes.h (16.22 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
// 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.
/** @file locale_classes.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
//
// ISO C++ 14882: 22.1 Locales
//
#ifndef _LOCALE_CLASSES_H
#define _LOCALE_CLASSES_H 1
#pragma GCC system_header
#include <bits/localefwd.h>
#include <cstring> // For strcmp.
#include <string>
#include <ext/atomicity.h>
_GLIBCXX_BEGIN_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_dispatch(&_M_refcount, 1); }
inline void
_M_remove_reference() const throw()
{
if (__gnu_cxx::__exchange_and_add_dispatch(&_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_dispatch(&_M_refcount, 1); }
inline void
_M_remove_reference() throw()
{
if (__gnu_cxx::__exchange_and_add_dispatch(&_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.
}
_GLIBCXX_END_NAMESPACE
#endif
|