path: root/lib/b64.go

// Copyright © 2020 rsiddharth <s@ricketyspace.net>
// SPDX-License-Identifier: ISC

package lib

const b64_table = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

func HexToBase64(hex string) string {
	hb := []byte(hex)

	b64 := ""
	for i := 0; i <= len(hb)-3; i = i + 3 {
		a := (HexCharToDec(hb[i])<<8 |
			HexCharToDec(hb[i+1])<<4 |
			HexCharToDec(hb[i+2]))
		b64 += encode(a >> 6)
		b64 += encode(a & 0b111111)
	}
	return b64
}

func encode(b uint16) string {
	return string(b64_table[b])
}