29 lines
709 B
JavaScript
29 lines
709 B
JavaScript
/* eslint-env browser */
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const perf = typeof performance === 'undefined' ? null : performance
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const isoCrypto = typeof crypto === 'undefined' ? null : crypto
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/**
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* @type {function(number):ArrayBuffer}
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*/
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const cryptoRandomBuffer = isoCrypto !== null
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? len => {
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// browser
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const buf = new ArrayBuffer(len)
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const arr = new Uint8Array(buf)
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isoCrypto.getRandomValues(arr)
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return buf
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}
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: len => {
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// polyfill
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const buf = new ArrayBuffer(len)
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const arr = new Uint8Array(buf)
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for (let i = 0; i < len; i++) {
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arr[i] = Math.ceil((Math.random() * 0xFFFFFFFF) >>> 0)
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}
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return buf
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}
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exports.performance = perf
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exports.cryptoRandomBuffer = cryptoRandomBuffer
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