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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)
+# 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 <boost/iterator/iterator_adaptor.hpp>
+#include <boost/iterator/iterator_traits.hpp>
+
+#include <algorithm> // std::min
+
+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 = 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 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 typename iterator_value<Base>::type base_value_type;
+
+    void fill();
+
+    CharType dereference() const {
+        if(!m_buffer_out_full)
+            const_cast<this_t *>(this)->fill();
+        return m_buffer_out;
+    }
+
+    bool equal_impl(const this_t & rhs){
+        if(BitsIn < BitsOut) // discard any left over bits
+            return this->base_reference() == rhs.base_reference();
+        else{
+            // BitsIn > BitsOut  // zero fill
+            if(this->base_reference() == rhs.base_reference()){
+                m_end_of_sequence = true;
+                return 0 == m_remaining_bits;
+            }
+            return false;
+        }
+    }
+
+    // standard iterator interface
+    bool equal(const this_t & rhs) const {
+        return const_cast<this_t *>(this)->equal_impl(rhs);
+    }
+
+    void increment(){
+        m_buffer_out_full = false;
+    }
+
+    bool m_buffer_out_full;
+    CharType m_buffer_out;
+
+    // last read element from input
+    base_value_type m_buffer_in;
+
+    // number of bits to left in the input buffer.
+    unsigned int m_remaining_bits;
+
+    // flag to indicate we've reached end of data.
+    bool m_end_of_sequence;
+
+public:
+    // make composible buy using templated constructor
+    template<class T>
+    transform_width(T start) : 
+        super_t(Base(static_cast< T >(start))),
+        m_buffer_out_full(false),
+        // To disable GCC warning, but not truly necessary 
+	    //(m_buffer_in will be initialized later before being 
+	    //used because m_remaining_bits == 0)
+        m_buffer_in(0), 
+        m_remaining_bits(0),
+        m_end_of_sequence(false)
+    {}
+    // intel 7.1 doesn't like default copy constructor
+    transform_width(const transform_width & rhs) : 
+        super_t(rhs.base_reference()),
+        m_buffer_out_full(rhs.m_buffer_out_full),
+        m_buffer_out(rhs.m_buffer_out),
+        m_buffer_in(rhs.m_buffer_in),
+        m_remaining_bits(rhs.m_remaining_bits),
+        m_end_of_sequence(false)
+    {}
+};
+
+template<
+    class Base, 
+    int BitsOut, 
+    int BitsIn, 
+    class CharType
+>
+void transform_width<Base, BitsOut, BitsIn, CharType>::fill() {
+    unsigned int missing_bits = BitsOut;
+    m_buffer_out = 0;
+    do{
+        if(0 == m_remaining_bits){
+            if(m_end_of_sequence){
+                m_buffer_in = 0;
+                m_remaining_bits = missing_bits;
+            }
+            else{
+                m_buffer_in = * this->base_reference()++;
+                m_remaining_bits = BitsIn;
+            }
+        }
+
+        // append these bits to the next output
+        // up to the size of the output
+        unsigned int i = (std::min)(missing_bits, m_remaining_bits);
+        // shift interesting bits to least significant position
+        base_value_type j = m_buffer_in >> (m_remaining_bits - i);
+        // and mask off the un interesting higher bits
+        // note presumption of twos complement notation
+        j &= (1 << i) - 1;
+        // append then interesting bits to the output value
+        m_buffer_out <<= i;
+        m_buffer_out |= j;
+
+        // and update counters
+        missing_bits -= i;
+        m_remaining_bits -= i;
+    }while(0 < missing_bits);
+    m_buffer_out_full = true;
+}
+
+} // namespace iterators
+} // namespace archive
+} // namespace boost
+
+#endif // BOOST_ARCHIVE_ITERATORS_TRANSFORM_WIDTH_HPP