multicodec/src/util.js

JavaScript implementation of the multicodec specification

'use strict'

const varint = require('varint')
const uint8ArrayToString = require('uint8arrays/to-string')
const uint8ArrayFromString = require('uint8arrays/from-string')

module.exports = {
  numberToUint8Array,
  uint8ArrayToNumber,
  varintUint8ArrayEncode,
  varintEncode
}

function uint8ArrayToNumber (buf) {
  return parseInt(uint8ArrayToString(buf, 'base16'), 16)
}

function numberToUint8Array (num) {
  let hexString = num.toString(16)
  if (hexString.length % 2 === 1) {
    hexString = '0' + hexString
  }
  return uint8ArrayFromString(hexString, 'base16')
}

function varintUint8ArrayEncode (input) {
  return Uint8Array.from(varint.encode(uint8ArrayToNumber(input)))
}

function varintEncode (num) {
  return Uint8Array.from(varint.encode(num))
}