43 lines
921 B
C++
43 lines
921 B
C++
/*
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/.
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*
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* Copyright 2015 Danny Robson <danny@nerdcruft.net>
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*/
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#pragma once
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#include "../../view.hpp"
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#include <cstdint>
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#include <cstddef>
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// Austin Appleby's MumurHash1
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namespace cruft::hash {
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class murmur1 {
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public:
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using digest_t = uint32_t;
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using seed_t = uint32_t;
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murmur1 (seed_t _seed):
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m_seed (_seed)
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{ ; }
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static constexpr uint32_t mix (uint32_t h, uint32_t k)
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{
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constexpr uint32_t m = 0xc6a4a793;
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h += k;
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h *= m;
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h ^= h >> 16;
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return h;
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}
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digest_t operator() (cruft::view<const uint8_t*> data) const noexcept;
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private:
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seed_t m_seed;
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};
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} |