20 lines
407 B
JavaScript
20 lines
407 B
JavaScript
const { random } = require('@lukeed/csprng');
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var IDX=256, HEX=[], SIZE=256*16, BUFFER;
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while (IDX--) HEX[IDX] = (IDX + 256).toString(16).substring(1);
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function uid(len) {
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var str='', tmp=(len || 11), num=(1+tmp) / 2 | 0;
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if (!BUFFER || ((IDX + num) > SIZE)) {
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BUFFER = random(SIZE);
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IDX = 0;
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}
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while (num--) {
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str += HEX[BUFFER[IDX++]];
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}
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return str.substring(0, tmp);
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}
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exports.uid = uid; |