Qore Programming Language  1.12.0
xxhash.h
1 /*
2  xxHash - Extremely Fast Hash algorithm
3  Header File
4  Copyright (C) 2012-2014, Yann Collet.
5  BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
6 
7  Redistribution and use in source and binary forms, with or without
8  modification, are permitted provided that the following conditions are
9  met:
10 
11  * Redistributions of source code must retain the above copyright
12  notice, this list of conditions and the following disclaimer.
13  * Redistributions in binary form must reproduce the above
14  copyright notice, this list of conditions and the following disclaimer
15  in the documentation and/or other materials provided with the
16  distribution.
17 
18  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 
30  You can contact the author at :
31  - xxHash source repository : http://code.google.com/p/xxhash/
32 */
33 
34 /* Notice extracted from xxHash homepage :
35 
36 xxHash is an extremely fast Hash algorithm, running at RAM speed limits.
37 It also successfully passes all tests from the SMHasher suite.
38 
39 Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz)
40 
41 Name Speed Q.Score Author
42 xxHash 5.4 GB/s 10
43 CrapWow 3.2 GB/s 2 Andrew
44 MumurHash 3a 2.7 GB/s 10 Austin Appleby
45 SpookyHash 2.0 GB/s 10 Bob Jenkins
46 SBox 1.4 GB/s 9 Bret Mulvey
47 Lookup3 1.2 GB/s 9 Bob Jenkins
48 SuperFastHash 1.2 GB/s 1 Paul Hsieh
49 CityHash64 1.05 GB/s 10 Pike & Alakuijala
50 FNV 0.55 GB/s 5 Fowler, Noll, Vo
51 CRC32 0.43 GB/s 9
52 MD5-32 0.33 GB/s 10 Ronald L. Rivest
53 SHA1-32 0.28 GB/s 10
54 
55 Q.Score is a measure of quality of the hash function.
56 It depends on successfully passing SMHasher test set.
57 10 is a perfect score.
58 */
59 
60 #pragma once
61 
62 #if defined (__cplusplus)
63 extern "C" {
64 #endif
65 
66 
67 /*****************************
68  Includes
69 *****************************/
70 #include <cstddef> /* size_t */
71 
72 
73 /*****************************
74  Type
75 *****************************/
76 typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode;
77 
78 
79 
80 /*****************************
81  Simple Hash Functions
82 *****************************/
83 
84 unsigned int XXH32 (const void* input, size_t length, unsigned seed);
85 unsigned long long XXH64 (const void* input, size_t length, unsigned long long seed);
86 
87 /*
88 XXH32() :
89  Calculate the 32-bits hash of sequence "length" bytes stored at memory address "input".
90  The memory between input & input+length must be valid (allocated and read-accessible).
91  "seed" can be used to alter the result predictably.
92  This function successfully passes all SMHasher tests.
93  Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s
94 XXH64() :
95  Calculate the 64-bits hash of sequence of length "len" stored at memory address "input".
96 */
97 
98 
99 
100 /*****************************
101  Advanced Hash Functions
102 *****************************/
103 typedef hashdecl { long long ll[ 6]; } XXH32_state_t;
104 typedef hashdecl { long long ll[11]; } XXH64_state_t;
105 
106 /*
107 These structures allow static allocation of XXH states.
108 States must then be initialized using XXHnn_reset() before first use.
109 
110 If you prefer dynamic allocation, please refer to functions below.
111 */
112 
113 XXH32_state_t* XXH32_createState(void);
114 XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr);
115 
116 XXH64_state_t* XXH64_createState(void);
117 XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr);
118 
119 /*
120 These functions create and release memory for XXH state.
121 States must then be initialized using XXHnn_reset() before first use.
122 */
123 
124 
125 XXH_errorcode XXH32_reset (XXH32_state_t* statePtr, unsigned seed);
126 XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
127 unsigned int XXH32_digest (const XXH32_state_t* statePtr);
128 
129 XXH_errorcode XXH64_reset (XXH64_state_t* statePtr, unsigned long long seed);
130 XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
131 unsigned long long XXH64_digest (const XXH64_state_t* statePtr);
132 
133 /*
134 These functions calculate the xxHash of an input provided in multiple smaller packets,
135 as opposed to an input provided as a single block.
136 
137 XXH state space must first be allocated, using either static or dynamic method provided above.
138 
139 Start a new hash by initializing state with a seed, using XXHnn_reset().
140 
141 Then, feed the hash state by calling XXHnn_update() as many times as necessary.
142 Obviously, input must be valid, meaning allocated and read accessible.
143 The function returns an error code, with 0 meaning OK, and any other value meaning there is an error.
144 
145 Finally, you can produce a hash anytime, by using XXHnn_digest().
146 This function returns the final nn-bits hash.
147 You can nonetheless continue feeding the hash state with more input,
148 and therefore get some new hashes, by calling again XXHnn_digest().
149 
150 When you are done, don't forget to free XXH state space, using typically XXHnn_freeState().
151 */
152 
153 #if defined (__cplusplus)
154 }
155 #endif
156 
157 hashdecl qore_hash_str {
158  DLLLOCAL size_t operator()(const char* s1) const {
159 #if TARGET_BITS == 64
160 return XXH64(s1, strlen(s1), 0);
161 #else
162 return XXH32(s1, strlen(s1), 0);
163 #endif
164  }
165 };