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4 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
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29 #include "cx/hash_key.h"
32 void cx_hash_murmur(CxHashKey *key) {
33 unsigned char const *data = key->data.cbytes;
35 // extension: special value for NULL
36 key->hash = 1574210520u;
39 size_t len = key->len;
41 unsigned m = 0x5bd1e995;
43 unsigned h = 25 ^ len;
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;
64 h ^= (data[i + 2] & 0xFF) << 16;
65 __attribute__((__fallthrough__));
67 h ^= (data[i + 1] & 0xFF) << 8;
68 __attribute__((__fallthrough__));
70 h ^= (data[i + 0] & 0xFF);
72 __attribute__((__fallthrough__));
73 default: // do nothing
84 CxHashKey cx_hash_key_str(char const *str) {
87 key.len = str == NULL ? 0 : strlen(str);
92 CxHashKey cx_hash_key_bytes(
93 unsigned char const *bytes,
97 key.data.cbytes = bytes;
103 CxHashKey cx_hash_key(
110 cx_hash_murmur(&key);