20 lines
423 B
JavaScript
20 lines
423 B
JavaScript
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var createHash = require('create-hash')
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var Buffer = require('safe-buffer').Buffer
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module.exports = function (seed, len) {
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var t = Buffer.alloc(0)
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var i = 0
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var c
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while (t.length < len) {
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c = i2ops(i++)
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t = Buffer.concat([t, createHash('sha1').update(seed).update(c).digest()])
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}
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return t.slice(0, len)
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}
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function i2ops (c) {
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var out = Buffer.allocUnsafe(4)
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out.writeUInt32BE(c, 0)
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return out
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}
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