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xxhash.h
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1 /*
2  xxHash - Extremely Fast Hash algorithm
3  Header File
4  Copyright (C) 2012-2016, Yann Collet.
5 
6  BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
7 
8  Redistribution and use in source and binary forms, with or without
9  modification, are permitted provided that the following conditions are
10  met:
11 
12  * Redistributions of source code must retain the above copyright
13  notice, this list of conditions and the following disclaimer.
14  * Redistributions in binary form must reproduce the above
15  copyright notice, this list of conditions and the following disclaimer
16  in the documentation and/or other materials provided with the
17  distribution.
18 
19  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 
31  You can contact the author at :
32  - xxHash source repository : https://github.com/Cyan4973/xxHash
33 */
34 
35 /* Notice extracted from xxHash homepage :
36 
37 xxHash is an extremely fast Hash algorithm, running at RAM speed limits.
38 It also successfully passes all tests from the SMHasher suite.
39 
40 Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz)
41 
42 Name Speed Q.Score Author
43 xxHash 5.4 GB/s 10
44 CrapWow 3.2 GB/s 2 Andrew
45 MumurHash 3a 2.7 GB/s 10 Austin Appleby
46 SpookyHash 2.0 GB/s 10 Bob Jenkins
47 SBox 1.4 GB/s 9 Bret Mulvey
48 Lookup3 1.2 GB/s 9 Bob Jenkins
49 SuperFastHash 1.2 GB/s 1 Paul Hsieh
50 CityHash64 1.05 GB/s 10 Pike & Alakuijala
51 FNV 0.55 GB/s 5 Fowler, Noll, Vo
52 CRC32 0.43 GB/s 9
53 MD5-32 0.33 GB/s 10 Ronald L. Rivest
54 SHA1-32 0.28 GB/s 10
55 
56 Q.Score is a measure of quality of the hash function.
57 It depends on successfully passing SMHasher test set.
58 10 is a perfect score.
59 
60 A 64-bits version, named XXH64, is available since r35.
61 It offers much better speed, but for 64-bits applications only.
62 Name Speed on 64 bits Speed on 32 bits
63 XXH64 13.8 GB/s 1.9 GB/s
64 XXH32 6.8 GB/s 6.0 GB/s
65 */
66 
67 #ifndef XXHASH_H_5627135585666179
68 #define XXHASH_H_5627135585666179 1
69 
70 #if defined (__cplusplus)
71 extern "C" {
72 #endif
73 
74 
75 /* ****************************
76 * Definitions
77 ******************************/
78 #include <stddef.h> /* size_t */
79 typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode;
80 
81 
82 /* ****************************
83 * API modifier
84 ******************************/
94 #ifdef XXH_PRIVATE_API
95 # ifndef XXH_STATIC_LINKING_ONLY
96 # define XXH_STATIC_LINKING_ONLY
97 # endif
98 # if defined(__GNUC__)
99 # define XXH_PUBLIC_API static __inline __attribute__((unused))
100 # elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
101 # define XXH_PUBLIC_API static inline
102 # elif defined(_MSC_VER)
103 # define XXH_PUBLIC_API static __inline
104 # else
105 # define XXH_PUBLIC_API static /* this version may generate warnings for unused static functions; disable the relevant warning */
106 # endif
107 #else
108 # define XXH_PUBLIC_API /* do nothing */
109 #endif /* XXH_PRIVATE_API */
110 
122 #ifdef XXH_NAMESPACE
123 # define XXH_CAT(A,B) A##B
124 # define XXH_NAME2(A,B) XXH_CAT(A,B)
125 # define XXH_versionNumber XXH_NAME2(XXH_NAMESPACE, XXH_versionNumber)
126 # define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32)
127 # define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState)
128 # define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState)
129 # define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset)
130 # define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update)
131 # define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest)
132 # define XXH32_copyState XXH_NAME2(XXH_NAMESPACE, XXH32_copyState)
133 # define XXH32_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH32_canonicalFromHash)
134 # define XXH32_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH32_hashFromCanonical)
135 # define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64)
136 # define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState)
137 # define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState)
138 # define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset)
139 # define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update)
140 # define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest)
141 # define XXH64_copyState XXH_NAME2(XXH_NAMESPACE, XXH64_copyState)
142 # define XXH64_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH64_canonicalFromHash)
143 # define XXH64_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH64_hashFromCanonical)
144 #endif
145 
146 
147 /* *************************************
148 * Version
149 ***************************************/
150 #define XXH_VERSION_MAJOR 0
151 #define XXH_VERSION_MINOR 6
152 #define XXH_VERSION_RELEASE 2
153 #define XXH_VERSION_NUMBER (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE)
154 XXH_PUBLIC_API unsigned XXH_versionNumber (void);
155 
156 
157 /*-**********************************************************************
158 * 32-bits hash
159 ************************************************************************/
160 typedef unsigned int XXH32_hash_t;
161 
167 XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, unsigned int seed);
168 
169 /*====== Streaming ======*/
170 typedef struct XXH32_state_s XXH32_state_t; /* incomplete type */
172 XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr);
173 XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dst_state, const XXH32_state_t* src_state);
174 
175 XXH_PUBLIC_API XXH_errorcode XXH32_reset (XXH32_state_t* statePtr, unsigned int seed);
176 XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
177 XXH_PUBLIC_API XXH32_hash_t XXH32_digest (const XXH32_state_t* statePtr);
178 
179 /*
180 These functions generate the xxHash of an input provided in multiple segments.
181 Note that, for small input, they are slower than single-call functions, due to state management.
182 For small input, prefer `XXH32()` and `XXH64()` .
183 
184 XXH state must first be allocated, using XXH*_createState() .
185 
186 Start a new hash by initializing state with a seed, using XXH*_reset().
187 
188 Then, feed the hash state by calling XXH*_update() as many times as necessary.
189 Obviously, input must be allocated and read accessible.
190 The function returns an error code, with 0 meaning OK, and any other value meaning there is an error.
191 
192 Finally, a hash value can be produced anytime, by using XXH*_digest().
193 This function returns the nn-bits hash as an int or long long.
194 
195 It's still possible to continue inserting input into the hash state after a digest,
196 and generate some new hashes later on, by calling again XXH*_digest().
197 
198 When done, free XXH state space if it was allocated dynamically.
199 */
200 
201 /*====== Canonical representation ======*/
202 
203 typedef struct { unsigned char digest[4]; } XXH32_canonical_t;
204 XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash);
206 
207 /* Default result type for XXH functions are primitive unsigned 32 and 64 bits.
208 * The canonical representation uses human-readable write convention, aka big-endian (large digits first).
209 * These functions allow transformation of hash result into and from its canonical format.
210 * This way, hash values can be written into a file / memory, and remain comparable on different systems and programs.
211 */
212 
213 
214 #ifndef XXH_NO_LONG_LONG
215 /*-**********************************************************************
216 * 64-bits hash
217 ************************************************************************/
218 typedef unsigned long long XXH64_hash_t;
219 
225 XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t length, unsigned long long seed);
226 
227 /*====== Streaming ======*/
228 typedef struct XXH64_state_s XXH64_state_t; /* incomplete type */
230 XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr);
231 XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dst_state, const XXH64_state_t* src_state);
232 
233 XXH_PUBLIC_API XXH_errorcode XXH64_reset (XXH64_state_t* statePtr, unsigned long long seed);
234 XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
235 XXH_PUBLIC_API XXH64_hash_t XXH64_digest (const XXH64_state_t* statePtr);
236 
237 /*====== Canonical representation ======*/
238 typedef struct { unsigned char digest[8]; } XXH64_canonical_t;
239 XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash);
241 #endif /* XXH_NO_LONG_LONG */
242 
243 
244 #ifdef XXH_STATIC_LINKING_ONLY
245 
246 /* ================================================================================================
247  This section contains definitions which are not guaranteed to remain stable.
248  They may change in future versions, becoming incompatible with a different version of the library.
249  They shall only be used with static linking.
250  Never use these definitions in association with dynamic linking !
251 =================================================================================================== */
252 
253 /* These definitions are only meant to make possible
254  static allocation of XXH state, on stack or in a struct for example.
255  Never use members directly. */
256 
257 struct XXH32_state_s {
258  unsigned total_len_32;
259  unsigned large_len;
260  unsigned v1;
261  unsigned v2;
262  unsigned v3;
263  unsigned v4;
264  unsigned mem32[4]; /* buffer defined as U32 for alignment */
265  unsigned memsize;
266  unsigned reserved; /* never read nor write, will be removed in a future version */
267 }; /* typedef'd to XXH32_state_t */
268 
269 #ifndef XXH_NO_LONG_LONG /* remove 64-bits support */
270 struct XXH64_state_s {
271  unsigned long long total_len;
272  unsigned long long v1;
273  unsigned long long v2;
274  unsigned long long v3;
275  unsigned long long v4;
276  unsigned long long mem64[4]; /* buffer defined as U64 for alignment */
277  unsigned memsize;
278  unsigned reserved[2]; /* never read nor write, will be removed in a future version */
279 }; /* typedef'd to XXH64_state_t */
280 #endif
281 
282 #ifdef XXH_PRIVATE_API
283 # include "xxhash.c" /* include xxhash function bodies as `static`, for inlining */
284 #endif
285 
286 #endif /* XXH_STATIC_LINKING_ONLY */
287 
288 
289 #if defined (__cplusplus)
290 }
291 #endif
292 
293 #endif /* XXHASH_H_5627135585666179 */
Definition: xxhash.h:238
XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t *dst_state, const XXH32_state_t *src_state)
struct XXH64_state_s XXH64_state_t
Definition: xxhash.h:228
XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t *dst, XXH64_hash_t hash)
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)
XXH_PUBLIC_API unsigned XXH_versionNumber(void)
XXH_PUBLIC_API XXH32_hash_t XXH32(const void *input, size_t length, unsigned int seed)
XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t *dst, XXH32_hash_t hash)
XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t *src)
unsigned long long XXH64_hash_t
Definition: xxhash.h:218
unsigned int XXH32_hash_t
Definition: xxhash.h:160
XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t *statePtr, unsigned int seed)
XXH_errorcode
Definition: xxhash.h:79
XXH_PUBLIC_API XXH64_hash_t XXH64(const void *input, size_t length, unsigned long long seed)
XXH_PUBLIC_API XXH32_hash_t XXH32_digest(const XXH32_state_t *statePtr)
Definition: xxhash.h:79
XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t *statePtr, unsigned long long seed)
Definition: xxhash.h:203
XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t *dst_state, const XXH64_state_t *src_state)
XXH_PUBLIC_API XXH64_state_t * XXH64_createState(void)
XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t *statePtr)
#define XXH_PUBLIC_API
XXH_PRIVATE_API This is useful to include xxhash functions in static mode in order to inline them...
Definition: xxhash.h:108
XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t *statePtr)
XXH_PUBLIC_API XXH_errorcode XXH32_update(XXH32_state_t *statePtr, const void *input, size_t length)
struct XXH32_state_s XXH32_state_t
Definition: xxhash.h:170
XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t *src)
Definition: xxhash.h:79
XXH_PUBLIC_API XXH32_state_t * XXH32_createState(void)