/
index.js
50 lines (46 loc) · 1.09 KB
/
index.js
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var alphabet = '0123456789abcdef'
var encodeLookup = []
var decodeLookup = []
for (var i = 0; i < 256; i++) {
encodeLookup[i] = alphabet[i >> 4 & 0xf] + alphabet[i & 0xf]
if (i < 16) {
if (i < 10) {
decodeLookup[0x30 + i] = i
} else {
decodeLookup[0x61 - 10 + i] = i
}
}
}
/**
* Encode a Uint8Array to a hex string
*
* @param {Uint8Array} array Bytes to encode to string
* @return {String} hex string
*/
export function encode (array) {
var length = array.length
var string = ''
var i = 0
while (i < length) {
string += encodeLookup[array[i++]]
}
return string
}
/**
* Decodes a hex string to a Uint8Array
*
* @param {String} string hex string to decode to Uint8Array
* @return {Uint8Array} Uint8Array
*/
export function decode (string) {
var sizeof = string.length >> 1
var length = sizeof << 1
var array = new Uint8Array(sizeof)
var n = 0
var i = 0
while (i < length) {
array[n++] = decodeLookup[string.charCodeAt(i++)] << 4 | decodeLookup[string.charCodeAt(i++)]
}
return array
}
export default { encode, decode }