Thu, 28 Dec 2023 19:17:45 +0100
fix accidental generation of cxListIterator() symbol
563 | 1 | /* |
2 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. | |
3 | * | |
4 | * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved. | |
5 | * | |
6 | * Redistribution and use in source and binary forms, with or without | |
7 | * modification, are permitted provided that the following conditions are met: | |
8 | * | |
9 | * 1. Redistributions of source code must retain the above copyright | |
10 | * notice, this list of conditions and the following disclaimer. | |
11 | * | |
12 | * 2. Redistributions in binary form must reproduce the above copyright | |
13 | * notice, this list of conditions and the following disclaimer in the | |
14 | * documentation and/or other materials provided with the distribution. | |
15 | * | |
16 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
17 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE | |
20 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
26 | * POSSIBILITY OF SUCH DAMAGE. | |
27 | */ | |
28 | ||
29 | #include "cx/hash_key.h" | |
30 | #include <string.h> | |
31 | ||
32 | void cx_hash_murmur(CxHashKey *key) { | |
690 | 33 | unsigned char const *data = key->data; |
604 | 34 | if (data == NULL) { |
628
1e2be40f0cb5
use //-style single line comments everywhere
Mike Becker <universe@uap-core.de>
parents:
604
diff
changeset
|
35 | // extension: special value for NULL |
604 | 36 | key->hash = 1574210520u; |
37 | return; | |
38 | } | |
563 | 39 | size_t len = key->len; |
40 | ||
41 | unsigned m = 0x5bd1e995; | |
42 | unsigned r = 24; | |
43 | unsigned h = 25 ^ len; | |
44 | unsigned i = 0; | |
45 | while (len >= 4) { | |
46 | unsigned k = data[i + 0] & 0xFF; | |
47 | k |= (data[i + 1] & 0xFF) << 8; | |
48 | k |= (data[i + 2] & 0xFF) << 16; | |
49 | k |= (data[i + 3] & 0xFF) << 24; | |
50 | ||
51 | k *= m; | |
52 | k ^= k >> r; | |
53 | k *= m; | |
54 | ||
55 | h *= m; | |
56 | h ^= k; | |
57 | ||
58 | i += 4; | |
59 | len -= 4; | |
60 | } | |
61 | ||
62 | switch (len) { | |
63 | case 3: | |
64 | h ^= (data[i + 2] & 0xFF) << 16; | |
65 | __attribute__((__fallthrough__)); | |
66 | case 2: | |
67 | h ^= (data[i + 1] & 0xFF) << 8; | |
68 | __attribute__((__fallthrough__)); | |
69 | case 1: | |
70 | h ^= (data[i + 0] & 0xFF); | |
71 | h *= m; | |
72 | __attribute__((__fallthrough__)); | |
628
1e2be40f0cb5
use //-style single line comments everywhere
Mike Becker <universe@uap-core.de>
parents:
604
diff
changeset
|
73 | default: // do nothing |
678 | 74 | ; |
563 | 75 | } |
76 | ||
77 | h ^= h >> 13; | |
78 | h *= m; | |
79 | h ^= h >> 15; | |
80 | ||
81 | key->hash = h; | |
82 | } | |
83 | ||
84 | CxHashKey cx_hash_key_str(char const *str) { | |
85 | CxHashKey key; | |
690 | 86 | key.data = str; |
604 | 87 | key.len = str == NULL ? 0 : strlen(str); |
563 | 88 | cx_hash_murmur(&key); |
89 | return key; | |
90 | } | |
91 | ||
92 | CxHashKey cx_hash_key_bytes( | |
93 | unsigned char const *bytes, | |
94 | size_t len | |
95 | ) { | |
96 | CxHashKey key; | |
690 | 97 | key.data = bytes; |
563 | 98 | key.len = len; |
99 | cx_hash_murmur(&key); | |
100 | return key; | |
101 | } | |
102 | ||
103 | CxHashKey cx_hash_key( | |
603
c49104015a6b
fix missing const in cx_hash_key signature
Mike Becker <universe@uap-core.de>
parents:
563
diff
changeset
|
104 | void const *obj, |
563 | 105 | size_t len |
106 | ) { | |
107 | CxHashKey key; | |
690 | 108 | key.data = obj; |
563 | 109 | key.len = len; |
110 | cx_hash_murmur(&key); | |
111 | return key; | |
112 | } |