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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// Copyright 2017 crypto-browserify. All rights reserved. MIT license.import { Buffer } from "../../buffer.ts";import { nextTick } from "../../_next_tick.ts";
// limit of Crypto.getRandomValues()// https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValuesconst MAX_BYTES = 65536;
// Node supports requesting up to this number of bytes// https://github.com/nodejs/node/blob/master/lib/internal/crypto/random.js#L48const MAX_UINT32 = 4294967295;
export function randomBytes(  size: number,  cb?: (err: Error | null, b: Buffer) => void,) {  // phantomjs needs to throw  if (size > MAX_UINT32) {    throw new RangeError("requested too many random bytes");  }
  const bytes = Buffer.allocUnsafe(size);
  if (size > 0) { // getRandomValues fails on IE if size == 0    if (size > MAX_BYTES) { // this is the max bytes crypto.getRandomValues      // can do at once see https://developer.mozilla.org/en-US/docs/Web/API/window.crypto.getRandomValues      for (let generated = 0; generated < size; generated += MAX_BYTES) {        // buffer.slice automatically checks if the end is past the end of        // the buffer so we don't have to here        globalThis.crypto.getRandomValues(          bytes.slice(generated, generated + MAX_BYTES),        );      }    } else {      globalThis.crypto.getRandomValues(bytes);    }  }
  if (typeof cb === "function") {    return nextTick(function () {      cb(null, bytes);    });  }
  return bytes;}