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- #ifndef BOOST_ARCHIVE_ITERATORS_TRANSFORM_WIDTH_HPP
- #define BOOST_ARCHIVE_ITERATORS_TRANSFORM_WIDTH_HPP
- #if defined(_MSC_VER) && (_MSC_VER >= 1020)
- # pragma once
- #endif
- #include <boost/config.hpp>
- #include <boost/serialization/pfto.hpp>
- #include <boost/iterator/iterator_adaptor.hpp>
- #include <boost/iterator/iterator_traits.hpp>
- namespace boost {
- namespace archive {
- namespace iterators {
- template<
- class Base,
- int BitsOut,
- int BitsIn,
- class CharType = BOOST_DEDUCED_TYPENAME boost::iterator_value<Base>::type
- >
- 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();
- }
-
- 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){
-
- ++(this->base_reference());
- }
- }
- m_full = false;
- }
- CharType m_current_value;
-
- unsigned int m_displacement;
- base_value_type m_buffer;
-
- bool m_full;
-
- bool m_bufferfull;
- public:
-
- 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)
- {}
-
- 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);
-
- unsigned int j = m_buffer >> (bcount - i);
-
-
- j &= ~(-(1 << i));
-
- retval <<= i;
- retval |= j;
- missing_bits -= i;
- if(0 == missing_bits)
- break;
-
- ++(this->base_reference());
- m_bufferfull = false;
- }
- return retval;
- }
- }
- }
- }
- #endif
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