53 lines
1.3 KiB
C++
53 lines
1.3 KiB
C++
/*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* Copyright 2010-2016 Danny Robson <danny@nerdcruft.net>
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*/
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#ifndef __UTIL_HASH_FLETCHER_HPP
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#define __UTIL_HASH_FLETCHER_HPP
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#include "../types/bits.hpp"
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#include "../view.hpp"
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#include <cstdint>
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#include <cstdlib>
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///////////////////////////////////////////////////////////////////////////////
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namespace util::hash {
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template <typename DigestT>
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class fletcher {
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public:
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using digest_t = DigestT;
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using part_t = typename bytes_type<sizeof (digest_t) / 2>::uint;
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fletcher (part_t modulus, part_t a, part_t b);
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digest_t
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operator() (util::view<const std::uint8_t*>) const noexcept;
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private:
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struct state_t {
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part_t a, b;
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};
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const digest_t m_modulus;
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const state_t m_initial;
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};
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}
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#endif
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