906f3dca72
Summary: this is the key component extracted from diff: https://reviews.facebook.net/D14271 I separate it to a dedicated patch to make the review easier. Test Plan: added a unit test and passed it. Reviewers: haobo, sdong, dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D16245
43 lines
1.3 KiB
C++
43 lines
1.3 KiB
C++
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
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// This source code is licensed under the BSD-style license found in the
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// LICENSE file in the root directory of this source tree. An additional grant
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// of patent rights can be found in the PATENTS file in the same directory.
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//
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/*
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Murmurhash from http://sites.google.com/site/murmurhash/
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All code is released to the public domain. For business purposes, Murmurhash is
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under the MIT license.
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*/
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#pragma once
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#include <stdint.h>
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#include "rocksdb/slice.h"
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#if defined(__x86_64__)
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#define MURMUR_HASH MurmurHash64A
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uint64_t MurmurHash64A ( const void * key, int len, unsigned int seed );
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#define MurmurHash MurmurHash64A
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typedef uint64_t murmur_t;
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#elif defined(__i386__)
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#define MURMUR_HASH MurmurHash2
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unsigned int MurmurHash2 ( const void * key, int len, unsigned int seed );
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#define MurmurHash MurmurHash2
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typedef unsigned int murmur_t;
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#else
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#define MURMUR_HASH MurmurHashNeutral2
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unsigned int MurmurHashNeutral2 ( const void * key, int len, unsigned int seed );
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#define MurmurHash MurmurHashNeutral2
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typedef unsigned int murmur_t;
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#endif
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// Allow slice to be hashable by murmur hash.
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namespace rocksdb {
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struct murmur_hash {
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size_t operator()(const Slice& slice) const {
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return MurmurHash(slice.data(), slice.size(), 0);
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}
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};
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} // rocksdb
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