mirror of https://github.com/torvalds/linux.git
48 lines
1.1 KiB
C
48 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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#ifndef _SELINUX_HASH_H_
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#define _SELINUX_HASH_H_
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/*
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* Based on MurmurHash3, written by Austin Appleby and placed in the
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* public domain.
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*/
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static inline u32 av_hash(u32 key1, u32 key2, u32 key3, u32 mask)
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{
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static const u32 c1 = 0xcc9e2d51;
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static const u32 c2 = 0x1b873593;
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static const u32 r1 = 15;
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static const u32 r2 = 13;
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static const u32 m = 5;
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static const u32 n = 0xe6546b64;
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u32 hash = 0;
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#define mix(input) \
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do { \
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u32 v = input; \
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v *= c1; \
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v = (v << r1) | (v >> (32 - r1)); \
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v *= c2; \
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hash ^= v; \
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hash = (hash << r2) | (hash >> (32 - r2)); \
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hash = hash * m + n; \
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} while (0)
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mix(key1);
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mix(key2);
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mix(key3);
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#undef mix
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hash ^= hash >> 16;
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hash *= 0x85ebca6b;
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hash ^= hash >> 13;
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hash *= 0xc2b2ae35;
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hash ^= hash >> 16;
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return hash & mask;
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}
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#endif /* _SELINUX_HASH_H_ */
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