81 lines
2.5 KiB
C++
81 lines
2.5 KiB
C++
/*
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Copyright (c) 2009-2010 Christopher A. Taylor. All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright notice,
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this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright notice,
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this list of conditions and the following disclaimer in the documentation
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and/or other materials provided with the distribution.
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* Neither the name of LibCat nor the names of its contributors may be used
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to endorse or promote products derived from this software without
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specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
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LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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MurmurHash2 is a very fast noncryptographic 32/64-bit hash
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Algorithm by Austin Appleby <aappleby@gmail.com>
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http://murmurhash.googlepages.com/
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*/
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#ifndef CAT_MURMUR_HASH_2_HPP
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#define CAT_MURMUR_HASH_2_HPP
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#include <cat/Platform.hpp>
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namespace cat {
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// NOTE: Result is NOT endian-neutral. Use getLE().
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u32 MurmurHash32(const void *key, int bytes, u32 seed);
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u64 MurmurHash64(const void *key, int bytes, u64 seed);
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class IncrementalMurmurHash32
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{
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u32 _hash, _tail, _count, _size;
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static const u32 M = 0x5bd1e995;
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static const u32 R = 24;
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public:
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void Begin(u32 seed = 0);
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void Add(const void *data, int bytes);
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u32 End();
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};
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class IncrementalMurmurHash64
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{
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u32 _count;
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u64 _hash, _tail, _size;
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static const u64 M = 0xc6a4a7935bd1e995ULL;
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static const u64 R = 47;
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public:
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void Begin(u64 seed = 0);
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void Add(const void *data, int bytes);
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u64 End();
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};
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} // namespace cat
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#endif // CAT_MURMUR_HASH_2_HPP
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