util/cbfstool/lz4/lib/xxhash.h

   1 /*
   2    xxHash - Extremely Fast Hash algorithm
   3    Header File
   4    Copyright (C) 2012-2015, 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 #pragma once
  68
  69 #if defined (__cplusplus)
  70 extern "C" {
  71 #endif
  72
  73
  74 /*****************************
  75 *  Definitions
  76 *****************************/
  77 #include <stddef.h>   /* size_t */
  78 typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode;
  79
  80
  81 /*****************************
  82 *  Namespace Emulation
  83 *****************************/
  84 /* Motivations :
  85
  86 If you need to include xxHash into your library,
  87 but wish to avoid xxHash symbols to be present on your library interface
  88 in an effort to avoid potential name collision if another library also includes xxHash,
  89
  90 you can use XXH_NAMESPACE, which will automatically prefix any symbol from xxHash
  91 with the value of XXH_NAMESPACE (so avoid to keep it NULL, and avoid numeric values).
  92
  93 Note that no change is required within the calling program :
  94 it can still call xxHash functions using their regular name.
  95 They will be automatically translated by this header.
  96 */
  97 #ifdef XXH_NAMESPACE
  98 #  define XXH_CAT(A,B) A##B
  99 #  define XXH_NAME2(A,B) XXH_CAT(A,B)
 100 #  define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32)
 101 #  define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64)
 102 #  define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState)
 103 #  define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState)
 104 #  define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState)
 105 #  define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState)
 106 #  define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset)
 107 #  define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset)
 108 #  define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update)
 109 #  define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update)
 110 #  define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest)
 111 #  define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest)
 112 #endif
 113
 114
 115 /*****************************
 116 *  Simple Hash Functions
 117 *****************************/
 118
 119 unsigned int       XXH32 (const void* input, size_t length, unsigned seed);
 120 unsigned long long XXH64 (const void* input, size_t length, unsigned long long seed);
 121
 122 /*
 123 XXH32() :
 124     Calculate the 32-bits hash of sequence "length" bytes stored at memory address "input".
 125     The memory between input & input+length must be valid (allocated and read-accessible).
 126     "seed" can be used to alter the result predictably.
 127     This function successfully passes all SMHasher tests.
 128     Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s
 129 XXH64() :
 130     Calculate the 64-bits hash of sequence of length "len" stored at memory address "input".
 131     Faster on 64-bits systems. Slower on 32-bits systems.
 132 */
 133
 134
 135
 136 /*****************************
 137 *  Advanced Hash Functions
 138 *****************************/
 139 typedef struct { long long ll[ 6]; } XXH32_state_t;
 140 typedef struct { long long ll[11]; } XXH64_state_t;
 141
 142 /*
 143 These structures allow static allocation of XXH states.
 144 States must then be initialized using XXHnn_reset() before first use.
 145
 146 If you prefer dynamic allocation, please refer to functions below.
 147 */
 148
 149 XXH32_state_t* XXH32_createState(void);
 150 XXH_errorcode  XXH32_freeState(XXH32_state_t* statePtr);
 151
 152 XXH64_state_t* XXH64_createState(void);
 153 XXH_errorcode  XXH64_freeState(XXH64_state_t* statePtr);
 154
 155 /*
 156 These functions create and release memory for XXH state.
 157 States must then be initialized using XXHnn_reset() before first use.
 158 */
 159
 160
 161 XXH_errorcode XXH32_reset  (XXH32_state_t* statePtr, unsigned seed);
 162 XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
 163 unsigned int  XXH32_digest (const XXH32_state_t* statePtr);
 164
 165 XXH_errorcode      XXH64_reset  (XXH64_state_t* statePtr, unsigned long long seed);
 166 XXH_errorcode      XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
 167 unsigned long long XXH64_digest (const XXH64_state_t* statePtr);
 168
 169 /*
 170 These functions calculate the xxHash of an input provided in multiple smaller packets,
 171 as opposed to an input provided as a single block.
 172
 173 XXH state space must first be allocated, using either static or dynamic method provided above.
 174
 175 Start a new hash by initializing state with a seed, using XXHnn_reset().
 176
 177 Then, feed the hash state by calling XXHnn_update() as many times as necessary.
 178 Obviously, input must be valid, meaning allocated and read accessible.
 179 The function returns an error code, with 0 meaning OK, and any other value meaning there is an error.
 180
 181 Finally, you can produce a hash anytime, by using XXHnn_digest().
 182 This function returns the final nn-bits hash.
 183 You can nonetheless continue feeding the hash state with more input,
 184 and therefore get some new hashes, by calling again XXHnn_digest().
 185
 186 When you are done, don't forget to free XXH state space, using typically XXHnn_freeState().
 187 */
 188
 189
 190 #if defined (__cplusplus)
 191 }
 192 #endif