53 lines
1.5 KiB
JavaScript
53 lines
1.5 KiB
JavaScript
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/* eslint-disable */
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/**
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* JS Implementation of MurmurHash2
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*
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* @author <a href="mailto:gary.court@gmail.com">Gary Court</a>
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* @see http://github.com/garycourt/murmurhash-js
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* @author <a href="mailto:aappleby@gmail.com">Austin Appleby</a>
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* @see http://sites.google.com/site/murmurhash/
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*
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* @param {string} str ASCII only
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* @param {number} seed Positive integer only
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* @return {number} 32-bit positive integer hash
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*/
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function murmurhash2_32_gc(str, seed) {
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var l = str.length,
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h = seed ^ l,
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i = 0,
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k;
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while (l >= 4) {
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k = str.charCodeAt(i) & 0xff | (str.charCodeAt(++i) & 0xff) << 8 | (str.charCodeAt(++i) & 0xff) << 16 | (str.charCodeAt(++i) & 0xff) << 24;
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k = (k & 0xffff) * 0x5bd1e995 + (((k >>> 16) * 0x5bd1e995 & 0xffff) << 16);
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k ^= k >>> 24;
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k = (k & 0xffff) * 0x5bd1e995 + (((k >>> 16) * 0x5bd1e995 & 0xffff) << 16);
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h = (h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0x5bd1e995 & 0xffff) << 16) ^ k;
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l -= 4;
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++i;
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}
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switch (l) {
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case 3:
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h ^= (str.charCodeAt(i + 2) & 0xff) << 16;
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case 2:
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h ^= (str.charCodeAt(i + 1) & 0xff) << 8;
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case 1:
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h ^= str.charCodeAt(i) & 0xff;
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h = (h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0x5bd1e995 & 0xffff) << 16);
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}
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h ^= h >>> 13;
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h = (h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0x5bd1e995 & 0xffff) << 16);
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h ^= h >>> 15;
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return h >>> 0;
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}
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var hash = function hash(str) {
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return murmurhash2_32_gc(str, 1).toString(36);
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};
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export default hash;
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