boost/archive/iterators/wchar_from_mb.hpp
#ifndef BOOST_ARCHIVE_ITERATORS_WCHAR_FROM_MB_HPP
#define BOOST_ARCHIVE_ITERATORS_WCHAR_FROM_MB_HPP
// MS compatible compilers support #pragma once
#if defined(_MSC_VER)
# pragma once
#endif
/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// wchar_from_mb.hpp
// (C) Copyright 2002 Robert Ramey - http://www.rrsd.com .
// Use, modification and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// See http://www.boost.org for updates, documentation, and revision history.
#include <boost/assert.hpp>
#include <cctype>
#include <cstddef> // size_t
#include <cwchar> // mbstate_t and mbrtowc
#include <boost/config.hpp>
#if defined(BOOST_NO_STDC_NAMESPACE)
namespace std{
using ::mbstate_t;
using ::mbrtowc;
} // namespace std
#endif
#include <boost/serialization/throw_exception.hpp>
#include <boost/iterator/iterator_adaptor.hpp>
#include <boost/archive/iterators/dataflow_exception.hpp>
namespace boost {
namespace archive {
namespace iterators {
/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// class used by text archives to translate char strings to wchar_t
// strings of the currently selected locale
template<class Base>
class wchar_from_mb
: public boost::iterator_adaptor<
wchar_from_mb<Base>,
Base,
wchar_t,
single_pass_traversal_tag,
wchar_t
>
{
friend class boost::iterator_core_access;
typedef typename boost::iterator_adaptor<
wchar_from_mb<Base>,
Base,
wchar_t,
single_pass_traversal_tag,
wchar_t
> super_t;
typedef wchar_from_mb<Base> this_t;
wchar_t drain();
wchar_t dereference_impl() {
if(! m_full){
m_current_value = drain();
m_full = true;
}
return m_current_value;
}
wchar_t dereference() const {
return const_cast<this_t *>(this)->dereference_impl();
}
void increment(){
dereference_impl();
m_full = false;
++(this->base_reference());
};
wchar_t m_current_value;
bool m_full;
public:
// make composible buy using templated constructor
template<class T>
wchar_from_mb(T start) :
super_t(Base(static_cast< T >(start))),
m_full(false)
{}
// intel 7.1 doesn't like default copy constructor
wchar_from_mb(const wchar_from_mb & rhs) :
super_t(rhs.base_reference()),
m_full(rhs.m_full)
{}
};
template<class Base>
wchar_t wchar_from_mb<Base>::drain(){
std::mbstate_t mbs;
wchar_t retval;
std::size_t result;
do {
char val = *this->base_reference();
result = std::mbrtowc(&retval, &val, 1, &mbs);
if(result == static_cast<std::size_t>(-1))
boost::serialization::throw_exception(iterators::dataflow_exception(
iterators::dataflow_exception::invalid_conversion
));
} while (result == static_cast<std::size_t>(-2));
return retval;
}
} // namespace iterators
} // namespace archive
} // namespace boost
#endif // BOOST_ARCHIVE_ITERATORS_WCHAR_FROM_MB_HPP