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/* Copyright (c) 2011 Google, Inc. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining a copy */
/* of this software and associated documentation files (the "Software"), to deal */
/* in the Software without restriction, including without limitation the rights */
/* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell */
/* copies of the Software, and to permit persons to whom the Software is */
/* furnished to do so, subject to the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be included in */
/* all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR */
/* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, */
/* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE */
/* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER */
/* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, */
/* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN */
/* THE SOFTWARE. */
/* */
/* CityHash, by Geoff Pike and Jyrki Alakuijala */
/* */
/* This file provides a few functions for hashing strings. On x86-64 */
/* hardware in 2011, CityHash64() is faster than other high-quality */
/* hash functions, such as Murmur. This is largely due to higher */
/* instruction-level parallelism. CityHash64() and CityHash128() also perform */
/* well on hash-quality tests. */
/* */
/* CityHash128() is optimized for relatively long strings and returns */
/* a 128-bit hash. For strings more than about 2000 bytes it can be */
/* faster than CityHash64(). */
/* */
/* Functions in the CityHash family are not suitable for cryptography. */
/* */
/* WARNING: This code has not been tested on big-endian platforms! */
/* It is known to work well on little-endian platforms that have a small penalty */
/* for unaligned reads, such as current Intel and AMD moderate-to-high-end CPUs. */
/* */
/* By the way, for some hash functions, given strings a and b, the hash */
/* of a+b is easily derived from the hashes of a and b. This property */
/* doesn't hold for any hash functions in this file. */
#ifndef CITY_HASH_H_
# define CITY_HASH_H_
# include <stddef.h>
# ifdef _MSC_VER
typedef unsigned char uint8;
typedef unsigned int uint32;
typedef unsigned long long uint64;
# else
# include <stdint.h>
typedef uint8_t uint8;
typedef uint32_t uint32;
typedef uint64_t uint64;
# endif
# ifdef __cplusplus
extern "C" {
# endif
# pragma pack(1)
typedef struct
{
uint64 first, second;
} uint128;
# pragma pack()
# define Uint128Low64(x) ((x).first)
# define Uint128High64(x) ((x).second)
/* Hash function for a byte array. */
uint64 CityHash64(const char *buf, size_t len);
/* Hash function for a byte array. For convenience, a 64-bit seed is also */
/* hashed into the result. */
uint64 CityHash64WithSeed(const char *buf, size_t len, uint64 seed);
/* Hash function for a byte array. For convenience, two seeds are also */
/* hashed into the result. */
uint64 CityHash64WithSeeds(const char *buf, size_t len,
uint64 seed0, uint64 seed1);
/* Hash function for a byte array. */
uint128 CityHash128(const char *s, size_t len);
/* Hash function for a byte array. For convenience, a 128-bit seed is also */
/* hashed into the result. */
uint128 CityHash128WithSeed(const char *s, size_t len, uint128 seed);
# ifdef __cplusplus
}
# endif
#endif /* CITY_HASH_H_ */
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