#!/bin/bash

urlencode() {
    # Usage: urlencode string
    local l="${#1}"
    for (( i = 0 ; i < l ; i++ )); do
        offsetByte=${1:i:1}
        case "$offsetByte" in
            [a-zA-Z0-9.~_-]) printf "$offsetByte" ;;
            ' ') printf + ;;
            *) printf '%%%X' "'$offsetByte"
        esac
    done
}

urldecode() {
    # Usage: urldecode string
    data=${1//+/ }
    printf '%b' "${data//\%/\x}"
}