gcc/libstdc++-v3/include/bits/locale_classes.h
Jonathan Wakely 596676d66c libstdc++: Add comparison operators to types from Utilities clause
Some more C++20 changes from P1614R2, "The Mothership has Landed".

This removes all redundant equality and inequality operators in the
Utilities clause, as they can be synthesized from the remaining equality
operators.

It also removes the single redundant operator in the Localization
clause, because it didn't seem worth doing in a separate commit.

	* include/bits/allocator.h (operator!=): Do not define for C++20.
	* include/bits/locale_classes.h (operator!=): Likewise.
	* include/bits/std_function.h (operator==(nullptr_t, const function&))
	(operator!=(const function&, nullptr_t))
	(operator!=(nullptr_t, const function&)): Likewise.
	* include/ext/bitmap_allocator.h (operator!=): Likewise.
	* include/ext/debug_allocator.h (operator!=): Likewise.
	* include/ext/extptr_allocator.h (operator!=): Likewise.
	* include/ext/malloc_allocator.h (operator!=): Likewise.
	* include/ext/mt_allocator.h (operator!=): Likewise.
	* include/ext/new_allocator.h (operator!=): Likewise.
	* include/ext/pool_allocator.h (operator!=): Likewise.
	* include/ext/throw_allocator.h (operator!=): Likewise.
	* include/std/bitset (bitset::operator!=): Likewise.
	* include/std/memory_resource (operator!=): Likewise.
	* include/std/scoped_allocator (operator!=): Likewise.
2020-04-15 19:47:48 +01:00

856 lines
24 KiB
C++

// Locale support -*- C++ -*-
// Copyright (C) 1997-2020 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_classes.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{locale}
*/
//
// ISO C++ 14882: 22.1 Locales
//
#ifndef _LOCALE_CLASSES_H
#define _LOCALE_CLASSES_H 1
#pragma GCC system_header
#include <bits/localefwd.h>
#include <string>
#include <ext/atomicity.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
// 22.1.1 Class locale
/**
* @brief Container class for localization functionality.
* @ingroup locales
*
* 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.
*
* 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:
/**
* @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);
#if __cplusplus >= 201103L
/**
* @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 an undefined locale.
*/
explicit
locale(const std::string& __s) : locale(__s.c_str()) { }
/**
* @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 an undefined locale.
*/
locale(const locale& __base, const std::string& __s, category __cat)
: locale(__base, __s.c_str(), __cat) { }
#endif
/**
* @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 @a __f
* is added to @a __other, replacing an existing facet of type
* Facet if there is one. If @a __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.
*
* @tparam _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.
*/
_GLIBCXX_DEFAULT_ABI_TAG
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();
#if __cpp_impl_three_way_comparison < 201907L
/**
* @brief Locale inequality.
*
* @param __other The locale to compare against.
* @return ! (*this == __other)
*/
bool
operator!=(const locale& __other) const throw()
{ return !(this->operator==(__other)); }
#endif
/**
* @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 __loc The new locale to make global.
* @return Copy of the old global locale.
*/
static locale
global(const locale& __loc);
/**
* @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() throw();
static category
_S_normalize_category(category);
void
_M_coalesce(const locale& __base, const locale& __add, category __cat);
#if _GLIBCXX_USE_CXX11_ABI
static const id* const _S_twinned_facets[];
#endif
};
// 22.1.1.1.2 Class locale::facet
/**
* @brief Localization functionality base class.
* @ingroup locales
*
* 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) throw();
static void
_S_destroy_c_locale(__c_locale& __cloc);
static __c_locale
_S_lc_ctype_c_locale(__c_locale __cloc, const char* __s);
// Returns data from the underlying "C" library data for the
// classic locale.
static __c_locale
_S_get_c_locale();
_GLIBCXX_CONST static const char*
_S_get_c_name() throw();
#if __cplusplus < 201103L
private:
facet(const facet&); // Not defined.
facet&
operator=(const facet&); // Not defined.
#else
facet(const facet&) = delete;
facet&
operator=(const facet&) = delete;
#endif
private:
void
_M_add_reference() const throw()
{ __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }
void
_M_remove_reference() const throw()
{
// Be race-detector-friendly. For more info see bits/c++config.
_GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount);
if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1)
{
_GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount);
__try
{ delete this; }
__catch(...)
{ }
}
}
const facet* _M_sso_shim(const id*) const;
const facet* _M_cow_shim(const id*) const;
protected:
class __shim; // For internal use only.
};
// 22.1.1.1.3 Class locale::id
/**
* @brief Facet ID class.
* @ingroup locales
*
* 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 throw();
};
// 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[];
void
_M_add_reference() throw()
{ __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }
void
_M_remove_reference() throw()
{
// Be race-detector-friendly. For more info see bits/c++config.
_GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount);
if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1)
{
_GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount);
__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.
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 = __builtin_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>
void
_M_init_facet(_Facet* __facet)
{ _M_install_facet(&_Facet::id, __facet); }
template<typename _Facet>
void
_M_init_facet_unchecked(_Facet* __facet)
{
__facet->_M_add_reference();
_M_facets[_Facet::id._M_id()] = __facet;
}
void
_M_install_cache(const facet*, size_t);
void _M_init_extra(facet**);
void _M_init_extra(void*, void*, const char*, const char*);
};
/**
* @brief Facet for localized string comparison.
*
* This facet encapsulates the code to compare strings in a localized
* manner.
*
* The collate template uses protected virtual functions to provide
* the actual results. The public accessors forward the call to
* the virtual functions. These virtual functions are hooks for
* developers to implement the behavior they require from the
* collate facet.
*/
template<typename _CharT>
class _GLIBCXX_NAMESPACE_CXX11 collate : public locale::facet
{
public:
// Types:
//@{
/// Public typedefs
typedef _CharT char_type;
typedef basic_string<_CharT> string_type;
//@}
protected:
// Underlying "C" library locale information saved from
// initialization, needed by collate_byname as well.
__c_locale _M_c_locale_collate;
public:
/// Numpunct facet id.
static locale::id id;
/**
* @brief Constructor performs initialization.
*
* This is the constructor provided by the standard.
*
* @param __refs Passed to the base facet class.
*/
explicit
collate(size_t __refs = 0)
: facet(__refs), _M_c_locale_collate(_S_get_c_locale())
{ }
/**
* @brief Internal constructor. Not for general use.
*
* This is a constructor for use by the library itself to set up new
* locales.
*
* @param __cloc The C locale.
* @param __refs Passed to the base facet class.
*/
explicit
collate(__c_locale __cloc, size_t __refs = 0)
: facet(__refs), _M_c_locale_collate(_S_clone_c_locale(__cloc))
{ }
/**
* @brief Compare two strings.
*
* This function compares two strings and returns the result by calling
* collate::do_compare().
*
* @param __lo1 Start of string 1.
* @param __hi1 End of string 1.
* @param __lo2 Start of string 2.
* @param __hi2 End of string 2.
* @return 1 if string1 > string2, -1 if string1 < string2, else 0.
*/
int
compare(const _CharT* __lo1, const _CharT* __hi1,
const _CharT* __lo2, const _CharT* __hi2) const
{ return this->do_compare(__lo1, __hi1, __lo2, __hi2); }
/**
* @brief Transform string to comparable form.
*
* This function is a wrapper for strxfrm functionality. It takes the
* input string and returns a modified string that can be directly
* compared to other transformed strings. In the C locale, this
* function just returns a copy of the input string. In some other
* locales, it may replace two chars with one, change a char for
* another, etc. It does so by returning collate::do_transform().
*
* @param __lo Start of string.
* @param __hi End of string.
* @return Transformed string_type.
*/
string_type
transform(const _CharT* __lo, const _CharT* __hi) const
{ return this->do_transform(__lo, __hi); }
/**
* @brief Return hash of a string.
*
* This function computes and returns a hash on the input string. It
* does so by returning collate::do_hash().
*
* @param __lo Start of string.
* @param __hi End of string.
* @return Hash value.
*/
long
hash(const _CharT* __lo, const _CharT* __hi) const
{ return this->do_hash(__lo, __hi); }
// Used to abstract out _CharT bits in virtual member functions, below.
int
_M_compare(const _CharT*, const _CharT*) const throw();
size_t
_M_transform(_CharT*, const _CharT*, size_t) const throw();
protected:
/// Destructor.
virtual
~collate()
{ _S_destroy_c_locale(_M_c_locale_collate); }
/**
* @brief Compare two strings.
*
* This function is a hook for derived classes to change the value
* returned. @see compare().
*
* @param __lo1 Start of string 1.
* @param __hi1 End of string 1.
* @param __lo2 Start of string 2.
* @param __hi2 End of string 2.
* @return 1 if string1 > string2, -1 if string1 < string2, else 0.
*/
virtual int
do_compare(const _CharT* __lo1, const _CharT* __hi1,
const _CharT* __lo2, const _CharT* __hi2) const;
/**
* @brief Transform string to comparable form.
*
* This function is a hook for derived classes to change the value
* returned.
*
* @param __lo Start.
* @param __hi End.
* @return transformed string.
*/
virtual string_type
do_transform(const _CharT* __lo, const _CharT* __hi) const;
/**
* @brief Return hash of a string.
*
* This function computes and returns a hash on the input string. This
* function is a hook for derived classes to change the value returned.
*
* @param __lo Start of string.
* @param __hi End of string.
* @return Hash value.
*/
virtual long
do_hash(const _CharT* __lo, const _CharT* __hi) const;
};
template<typename _CharT>
locale::id collate<_CharT>::id;
// Specializations.
template<>
int
collate<char>::_M_compare(const char*, const char*) const throw();
template<>
size_t
collate<char>::_M_transform(char*, const char*, size_t) const throw();
#ifdef _GLIBCXX_USE_WCHAR_T
template<>
int
collate<wchar_t>::_M_compare(const wchar_t*, const wchar_t*) const throw();
template<>
size_t
collate<wchar_t>::_M_transform(wchar_t*, const wchar_t*, size_t) const throw();
#endif
/// class collate_byname [22.2.4.2].
template<typename _CharT>
class _GLIBCXX_NAMESPACE_CXX11 collate_byname : public collate<_CharT>
{
public:
//@{
/// Public typedefs
typedef _CharT char_type;
typedef basic_string<_CharT> string_type;
//@}
explicit
collate_byname(const char* __s, size_t __refs = 0)
: collate<_CharT>(__refs)
{
if (__builtin_strcmp(__s, "C") != 0
&& __builtin_strcmp(__s, "POSIX") != 0)
{
this->_S_destroy_c_locale(this->_M_c_locale_collate);
this->_S_create_c_locale(this->_M_c_locale_collate, __s);
}
}
#if __cplusplus >= 201103L
explicit
collate_byname(const string& __s, size_t __refs = 0)
: collate_byname(__s.c_str(), __refs) { }
#endif
protected:
virtual
~collate_byname() { }
};
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
# include <bits/locale_classes.tcc>
#endif