64 lines
1.6 KiB
C++
64 lines
1.6 KiB
C++
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/*
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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 2016 Danny Robson <danny@nerdcruft.net>
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*/
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#ifndef CRUFT_UTIL_HASH_XXHASH_HPP
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#define CRUFT_UTIL_HASH_XXHASH_HPP
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#include <cstdint>
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#include <type_traits>
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namespace util::hash {
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template <typename T>
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class xxhash {
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public:
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static_assert (std::is_same<T,uint32_t>::value || std::is_same<T,uint64_t>::value);
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using digest_t = T;
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xxhash (void);
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xxhash (uint32_t seed);
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void update (const uint8_t *restrict first, const uint8_t *restrict last);
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void finish (void);
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digest_t digest (void) const;
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void reset (void);
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private:
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uint32_t m_seed;
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struct {
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uint32_t total_len_32;
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uint32_t large_len;
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T v1, v2, v3, v4;
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uint32_t mem32[4];
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uint32_t memsize;
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uint32_t reserved;
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//uint64_t length;
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//T v[4];
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//T mem[4];
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//unsigned memsize;
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} m_state;
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};
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using xxhash32 = xxhash<uint32_t>;
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using xxhash64 = xxhash<uint64_t>;
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}
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#endif
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