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+#ifndef BOOST_ARCHIVE_ITERATORS_TRANSFORM_WIDTH_HPP
+#define BOOST_ARCHIVE_ITERATORS_TRANSFORM_WIDTH_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
+// transform_width.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.
+
+// iterator which takes elements of x bits and returns elements of y bits.
+// used to change streams of 8 bit characters into streams of 6 bit characters.
+// and vice-versa for implementing base64 encodeing/decoding. Be very careful
+// when using and end iterator. end is only reliable detected when the input
+// stream length is some common multiple of x and y. E.G. Base64 6 bit
+// character and 8 bit bytes. Lowest common multiple is 24 => 4 6 bit characters
+// or 3 8 bit characters
+
+#include <algorithm>
+
+#include <boost/config.hpp> // for BOOST_DEDUCED_TYPENAME & PTFO
+#include <boost/serialization/pfto.hpp>
+
+#include <boost/iterator/iterator_adaptor.hpp>
+#include <boost/iterator/iterator_traits.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,
+ int BitsOut,
+ int BitsIn,
+ class CharType = BOOST_DEDUCED_TYPENAME boost::iterator_value<Base>::type // output character
+>
+class transform_width :
+ public boost::iterator_adaptor<
+ transform_width<Base, BitsOut, BitsIn, CharType>,
+ Base,
+ CharType,
+ single_pass_traversal_tag,
+ CharType
+ >
+{
+ friend class boost::iterator_core_access;
+ typedef BOOST_DEDUCED_TYPENAME boost::iterator_adaptor<
+ transform_width<Base, BitsOut, BitsIn, CharType>,
+ Base,
+ CharType,
+ single_pass_traversal_tag,
+ CharType
+ > super_t;
+
+ typedef transform_width<Base, BitsOut, BitsIn, CharType> this_t;
+ typedef BOOST_DEDUCED_TYPENAME iterator_value<Base>::type base_value_type;
+
+ CharType fill();
+
+ CharType dereference_impl(){
+ if(! m_full){
+ m_current_value = fill();
+ m_full = true;
+ }
+ return m_current_value;
+ }
+
+ CharType dereference() const {
+ return const_cast<this_t *>(this)->dereference_impl();
+ }
+
+ // test for iterator equality
+ bool equal(const this_t & rhs) const {
+ return
+ this->base_reference() == rhs.base_reference();
+ ;
+ }
+
+ void increment(){
+ m_displacement += BitsOut;
+
+ while(m_displacement >= BitsIn){
+ m_displacement -= BitsIn;
+ if(0 == m_displacement)
+ m_bufferfull = false;
+ if(! m_bufferfull){
+ // note: suspect that this is not invoked for borland
+ ++(this->base_reference());
+ }
+ }
+ m_full = false;
+ }
+
+ CharType m_current_value;
+ // number of bits left in current input character buffer
+ unsigned int m_displacement;
+ base_value_type m_buffer;
+ // flag to current output character is ready - just used to save time
+ bool m_full;
+ // flag to indicate that m_buffer has data
+ bool m_bufferfull;
+
+public:
+ // make composible buy using templated constructor
+ template<class T>
+ transform_width(BOOST_PFTO_WRAPPER(T) start) :
+ super_t(Base(BOOST_MAKE_PFTO_WRAPPER(static_cast< T >(start)))),
+ m_displacement(0),
+ m_full(false),
+ m_bufferfull(false)
+ {}
+ // intel 7.1 doesn't like default copy constructor
+ transform_width(const transform_width & rhs) :
+ super_t(rhs.base_reference()),
+ m_current_value(rhs.m_current_value),
+ m_displacement(rhs.m_displacement),
+ m_buffer(rhs.m_buffer),
+ m_full(rhs.m_full),
+ m_bufferfull(rhs.m_bufferfull)
+ {}
+};
+
+template<class Base, int BitsOut, int BitsIn, class CharType>
+CharType transform_width<Base, BitsOut, BitsIn, CharType>::fill(){
+ CharType retval = 0;
+ unsigned int missing_bits = BitsOut;
+ for(;;){
+ unsigned int bcount;
+ if(! m_bufferfull){
+ m_buffer = * this->base_reference();
+ m_bufferfull = true;
+ bcount = BitsIn;
+ }
+ else
+ bcount = BitsIn - m_displacement;
+ unsigned int i = (std::min)(bcount, missing_bits);
+ // shift interesting bits to least significant position
+ unsigned int j = m_buffer >> (bcount - i);
+ // strip off uninteresting bits
+ // (note presumption of two's complement arithmetic)
+ j &= ~(-(1 << i));
+ // append then interesting bits to the output value
+ retval <<= i;
+ retval |= j;
+ missing_bits -= i;
+ if(0 == missing_bits)
+ break;
+ // note: suspect that this is not invoked for borland 5.51
+ ++(this->base_reference());
+ m_bufferfull = false;
+ }
+ return retval;
+}
+
+} // namespace iterators
+} // namespace archive
+} // namespace boost
+
+#endif // BOOST_ARCHIVE_ITERATORS_TRANSFORM_WIDTH_HPP