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| -rw-r--r-- | src/zstd/lib/common/xxhash.h | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/src/zstd/lib/common/xxhash.h b/src/zstd/lib/common/xxhash.h new file mode 100644 index 000000000..4207eba83 --- /dev/null +++ b/src/zstd/lib/common/xxhash.h @@ -0,0 +1,285 @@ +/* + * xxHash - Extremely Fast Hash algorithm + * Header File + * Copyright (c) 2012-2020, Yann Collet, Facebook, Inc. + * + * You can contact the author at : + * - xxHash source repository : https://github.com/Cyan4973/xxHash + * + * This source code is licensed under both the BSD-style license (found in the + * LICENSE file in the root directory of this source tree) and the GPLv2 (found + * in the COPYING file in the root directory of this source tree). + * You may select, at your option, one of the above-listed licenses. +*/ + +/* Notice extracted from xxHash homepage : + +xxHash is an extremely fast Hash algorithm, running at RAM speed limits. +It also successfully passes all tests from the SMHasher suite. + +Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz) + +Name Speed Q.Score Author +xxHash 5.4 GB/s 10 +CrapWow 3.2 GB/s 2 Andrew +MumurHash 3a 2.7 GB/s 10 Austin Appleby +SpookyHash 2.0 GB/s 10 Bob Jenkins +SBox 1.4 GB/s 9 Bret Mulvey +Lookup3 1.2 GB/s 9 Bob Jenkins +SuperFastHash 1.2 GB/s 1 Paul Hsieh +CityHash64 1.05 GB/s 10 Pike & Alakuijala +FNV 0.55 GB/s 5 Fowler, Noll, Vo +CRC32 0.43 GB/s 9 +MD5-32 0.33 GB/s 10 Ronald L. Rivest +SHA1-32 0.28 GB/s 10 + +Q.Score is a measure of quality of the hash function. +It depends on successfully passing SMHasher test set. +10 is a perfect score. + +A 64-bits version, named XXH64, is available since r35. +It offers much better speed, but for 64-bits applications only. +Name Speed on 64 bits Speed on 32 bits +XXH64 13.8 GB/s 1.9 GB/s +XXH32 6.8 GB/s 6.0 GB/s +*/ + +#if defined (__cplusplus) +extern "C" { +#endif + +#ifndef XXHASH_H_5627135585666179 +#define XXHASH_H_5627135585666179 1 + + +/* **************************** +* Definitions +******************************/ +#include <stddef.h> /* size_t */ +typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode; + + +/* **************************** +* API modifier +******************************/ +/** XXH_PRIVATE_API +* This is useful if you want to include xxhash functions in `static` mode +* in order to inline them, and remove their symbol from the public list. +* Methodology : +* #define XXH_PRIVATE_API +* #include "xxhash.h" +* `xxhash.c` is automatically included. +* It's not useful to compile and link it as a separate module anymore. +*/ +#ifdef XXH_PRIVATE_API +# ifndef XXH_STATIC_LINKING_ONLY +# define XXH_STATIC_LINKING_ONLY +# endif +# if defined(__GNUC__) +# define XXH_PUBLIC_API static __inline __attribute__((unused)) +# elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) +# define XXH_PUBLIC_API static inline +# elif defined(_MSC_VER) +# define XXH_PUBLIC_API static __inline +# else +# define XXH_PUBLIC_API static /* this version may generate warnings for unused static functions; disable the relevant warning */ +# endif +#else +# define XXH_PUBLIC_API /* do nothing */ +#endif /* XXH_PRIVATE_API */ + +/*!XXH_NAMESPACE, aka Namespace Emulation : + +If you want to include _and expose_ xxHash functions from within your own library, +but also want to avoid symbol collisions with another library which also includes xxHash, + +you can use XXH_NAMESPACE, to automatically prefix any public symbol from xxhash library +with the value of XXH_NAMESPACE (so avoid to keep it NULL and avoid numeric values). + +Note that no change is required within the calling program as long as it includes `xxhash.h` : +regular symbol name will be automatically translated by this header. +*/ +#ifdef XXH_NAMESPACE +# define XXH_CAT(A,B) A##B +# define XXH_NAME2(A,B) XXH_CAT(A,B) +# define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32) +# define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64) +# define XXH_versionNumber XXH_NAME2(XXH_NAMESPACE, XXH_versionNumber) +# define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState) +# define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState) +# define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState) +# define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState) +# define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset) +# define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset) +# define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update) +# define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update) +# define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest) +# define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest) +# define XXH32_copyState XXH_NAME2(XXH_NAMESPACE, XXH32_copyState) +# define XXH64_copyState XXH_NAME2(XXH_NAMESPACE, XXH64_copyState) +# define XXH32_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH32_canonicalFromHash) +# define XXH64_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH64_canonicalFromHash) +# define XXH32_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH32_hashFromCanonical) +# define XXH64_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH64_hashFromCanonical) +#endif + + +/* ************************************* +* Version +***************************************/ +#define XXH_VERSION_MAJOR 0 +#define XXH_VERSION_MINOR 6 +#define XXH_VERSION_RELEASE 2 +#define XXH_VERSION_NUMBER (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE) +XXH_PUBLIC_API unsigned XXH_versionNumber (void); + + +/* **************************** +* Simple Hash Functions +******************************/ +typedef unsigned int XXH32_hash_t; +typedef unsigned long long XXH64_hash_t; + +XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, unsigned int seed); +XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t length, unsigned long long seed); + +/*! +XXH32() : + Calculate the 32-bits hash of sequence "length" bytes stored at memory address "input". + The memory between input & input+length must be valid (allocated and read-accessible). + "seed" can be used to alter the result predictably. + Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s +XXH64() : + Calculate the 64-bits hash of sequence of length "len" stored at memory address "input". + "seed" can be used to alter the result predictably. + This function runs 2x faster on 64-bits systems, but slower on 32-bits systems (see benchmark). +*/ + + +/* **************************** +* Streaming Hash Functions +******************************/ +typedef struct XXH32_state_s XXH32_state_t; /* incomplete type */ +typedef struct XXH64_state_s XXH64_state_t; /* incomplete type */ + +/*! State allocation, compatible with dynamic libraries */ + +XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void); +XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr); + +XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void); +XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr); + + +/* hash streaming */ + +XXH_PUBLIC_API XXH_errorcode XXH32_reset (XXH32_state_t* statePtr, unsigned int seed); +XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length); +XXH_PUBLIC_API XXH32_hash_t XXH32_digest (const XXH32_state_t* statePtr); + +XXH_PUBLIC_API XXH_errorcode XXH64_reset (XXH64_state_t* statePtr, unsigned long long seed); +XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length); +XXH_PUBLIC_API XXH64_hash_t XXH64_digest (const XXH64_state_t* statePtr); + +/* +These functions generate the xxHash of an input provided in multiple segments. +Note that, for small input, they are slower than single-call functions, due to state management. +For small input, prefer `XXH32()` and `XXH64()` . + +XXH state must first be allocated, using XXH*_createState() . + +Start a new hash by initializing state with a seed, using XXH*_reset(). + +Then, feed the hash state by calling XXH*_update() as many times as necessary. +Obviously, input must be allocated and read accessible. +The function returns an error code, with 0 meaning OK, and any other value meaning there is an error. + +Finally, a hash value can be produced anytime, by using XXH*_digest(). +This function returns the nn-bits hash as an int or long long. + +It's still possible to continue inserting input into the hash state after a digest, +and generate some new hashes later on, by calling again XXH*_digest(). + +When done, free XXH state space if it was allocated dynamically. +*/ + + +/* ************************** +* Utils +****************************/ +#if !(defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)) /* ! C99 */ +# define restrict /* disable restrict */ +#endif + +XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* restrict dst_state, const XXH32_state_t* restrict src_state); +XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* restrict dst_state, const XXH64_state_t* restrict src_state); + + +/* ************************** +* Canonical representation +****************************/ +/* Default result type for XXH functions are primitive unsigned 32 and 64 bits. +* The canonical representation uses human-readable write convention, aka big-endian (large digits first). +* These functions allow transformation of hash result into and from its canonical format. +* This way, hash values can be written into a file / memory, and remain comparable on different systems and programs. +*/ +typedef struct { unsigned char digest[4]; } XXH32_canonical_t; +typedef struct { unsigned char digest[8]; } XXH64_canonical_t; + +XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash); +XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash); + +XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src); +XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src); + +#endif /* XXHASH_H_5627135585666179 */ + + + +/* ================================================================================================ + This section contains definitions which are not guaranteed to remain stable. + They may change in future versions, becoming incompatible with a different version of the library. + They shall only be used with static linking. + Never use these definitions in association with dynamic linking ! +=================================================================================================== */ +#if defined(XXH_STATIC_LINKING_ONLY) && !defined(XXH_STATIC_H_3543687687345) +#define XXH_STATIC_H_3543687687345 + +/* These definitions are only meant to allow allocation of XXH state + statically, on stack, or in a struct for example. + Do not use members directly. */ + + struct XXH32_state_s { + unsigned total_len_32; + unsigned large_len; + unsigned v1; + unsigned v2; + unsigned v3; + unsigned v4; + unsigned mem32[4]; /* buffer defined as U32 for alignment */ + unsigned memsize; + unsigned reserved; /* never read nor write, will be removed in a future version */ + }; /* typedef'd to XXH32_state_t */ + + struct XXH64_state_s { + unsigned long long total_len; + unsigned long long v1; + unsigned long long v2; + unsigned long long v3; + unsigned long long v4; + unsigned long long mem64[4]; /* buffer defined as U64 for alignment */ + unsigned memsize; + unsigned reserved[2]; /* never read nor write, will be removed in a future version */ + }; /* typedef'd to XXH64_state_t */ + + +# ifdef XXH_PRIVATE_API +# include "xxhash.c" /* include xxhash functions as `static`, for inlining */ +# endif + +#endif /* XXH_STATIC_LINKING_ONLY && XXH_STATIC_H_3543687687345 */ + + +#if defined (__cplusplus) +} +#endif |