Sprout/sprout/checksum/xor.hpp
2014-01-08 16:48:12 +09:00

91 lines
3 KiB
C++

/*=============================================================================
Copyright (c) 2011-2014 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
Distributed under 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)
=============================================================================*/
#ifndef SPROUT_CHECKSUM_XOR_HPP
#define SPROUT_CHECKSUM_XOR_HPP
#include <cstddef>
#include <cstdint>
#include <sprout/config.hpp>
#include <sprout/container/functions.hpp>
#include <sprout/iterator/operation.hpp>
#include <sprout/iterator/bytes_iterator.hpp>
#include <sprout/numeric/accumulate.hpp>
#include <sprout/functional/polymorphic/bit_xor.hpp>
namespace sprout {
//
// xor8
//
class xor8 {
public:
typedef std::uint8_t value_type;
typedef xor8 const const_type;
typedef std::size_t sum_type;
private:
sum_type sum_;
private:
template<typename InputIterator>
SPROUT_CONSTEXPR sum_type calc_sum(InputIterator first, InputIterator last) const {
return sprout::accumulate(
sprout::make_bytes_iterator(first),
sprout::make_bytes_iterator(last),
sum_,
sprout::bit_xor_
);
}
public:
xor8(xor8 const&) = default;
explicit SPROUT_CONSTEXPR xor8(sum_type sum)
: sum_(sum)
{}
SPROUT_CXX14_CONSTEXPR void reset(sum_type new_sum = 0) {
sum_ = new_sum;
}
SPROUT_CONSTEXPR xor8 const process_byte(std::uint8_t byte) const {
return xor8(sum_ ^ byte);
}
template<typename InputIterator>
SPROUT_CONSTEXPR xor8 const process_block(InputIterator bytes_begin, InputIterator bytes_end) const {
return xor8(calc_sum(bytes_begin, bytes_end));
}
template<typename InputIterator>
SPROUT_CONSTEXPR xor8 const process_bytes(InputIterator buffer, std::size_t byte_count) const {
return process_block(buffer, sprout::next(buffer, byte_count));
}
template<typename InputRange>
SPROUT_CONSTEXPR xor8 const process_range(InputRange const& bytes_range) const {
return process_block(sprout::begin(bytes_range), sprout::end(bytes_range));
}
SPROUT_CXX14_CONSTEXPR void process_byte(std::uint8_t byte) {
sum_ ^= byte;
}
template<typename InputIterator>
SPROUT_CXX14_CONSTEXPR void process_block(InputIterator bytes_begin, InputIterator bytes_end) {
sum_ = calc_sum(bytes_begin, bytes_end);
}
template<typename InputIterator>
SPROUT_CXX14_CONSTEXPR void process_bytes(InputIterator buffer, std::size_t byte_count) {
process_block(buffer, sprout::next(buffer, byte_count));
}
template<typename InputRange>
SPROUT_CXX14_CONSTEXPR void process_range(InputRange const& bytes_range) {
process_block(sprout::begin(bytes_range), sprout::end(bytes_range));
}
SPROUT_CONSTEXPR value_type checksum() const {
return static_cast<value_type>(sum_ & 0xFF);
}
SPROUT_CONSTEXPR value_type operator()() const {
return checksum();
}
};
} // namespace sprout
#endif // #ifndef SPROUT_CHECKSUM_XOR_HPP