#ifndef BOOST_ARCHIVE_ITERATORS_BINARY_FROM_BASE64_HPP
#define BOOST_ARCHIVE_ITERATORS_BINARY_FROM_BASE64_HPP
// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// binary_from_base64.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 <boost/config.hpp> // for BOOST_DEDUCED_TYPENAME
#include <boost/serialization/throw_exception.hpp>
#include <boost/serialization/pfto.hpp>
#include <boost/static_assert.hpp>
#include <boost/iterator/transform_iterator.hpp>
#include <boost/archive/iterators/dataflow_exception.hpp>
namespace boost {
namespace archive {
namespace iterators {
/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// convert base64 characters to binary data
namespace detail {
template<class CharType>
struct to_6_bit {
typedef CharType result_type;
CharType operator()(CharType t) const{
const char lookup_table[] = {
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,62,-1,-1,-1,63,
52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-1,-1,-1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,
15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,
-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,
41,42,43,44,45,46,47,48,49,50,51,-1,-1,-1,-1,-1
};
// metrowerks trips this assertion - how come?
#if ! defined(__MWERKS__)
BOOST_STATIC_ASSERT(128 == sizeof(lookup_table));
#endif
signed char value = -1;
if((unsigned)t <= 127)
value = lookup_table[(unsigned)t];
if(-1 == value)
boost::serialization::throw_exception(
dataflow_exception(dataflow_exception::invalid_base64_character)
);
return value;
}
};
} // namespace detail
// note: what we would like to do is
// template<class Base, class CharType = BOOST_DEDUCED_TYPENAME Base::value_type>
// typedef transform_iterator<
// from_6_bit<CharType>,
// transform_width<Base, 6, sizeof(Base::value_type) * 8, CharType>
// > base64_from_binary;
// but C++ won't accept this. Rather than using a "type generator" and
// using a different syntax, make a derivation which should be equivalent.
//
// Another issue addressed here is that the transform_iterator doesn't have
// a templated constructor. This makes it incompatible with the dataflow
// ideal. This is also addressed here.
template<
class Base,
class CharType = BOOST_DEDUCED_TYPENAME boost::iterator_value<Base>::type
>
class binary_from_base64 : public
transform_iterator<
detail::to_6_bit<CharType>,
Base
>
{
friend class boost::iterator_core_access;
typedef transform_iterator<
detail::to_6_bit<CharType>,
Base
> super_t;
public:
// make composible buy using templated constructor
template<class T>
binary_from_base64(BOOST_PFTO_WRAPPER(T) start) :
super_t(
Base(BOOST_MAKE_PFTO_WRAPPER(static_cast< T >(start))),
detail::to_6_bit<CharType>()
)
{}
// intel 7.1 doesn't like default copy constructor
binary_from_base64(const binary_from_base64 & rhs) :
super_t(
Base(rhs.base_reference()),
detail::to_6_bit<CharType>()
)
{}
// binary_from_base64(){};
};
} // namespace iterators
} // namespace archive
} // namespace boost
#endif // BOOST_ARCHIVE_ITERATORS_BINARY_FROM_BASE64_HPP
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