sed.headache.sh

#!/bin/bash
# https://www.debuggex.com/r/Hutq6OGOTwM8Qevp
#

#!/bin/sh
a() {
    tmp=${1##*://}
    proto=${1//:*/}
    cn=${tmp%:*}
    port=${1##*:}
    port=${port-1194}
    proto=${proto-udp}
}

b() {
    a=$(echo "$@" | sed -re 's#((udp|tcp)://)?([0-9a-zA-Z\.]+)(:([0-9]+))?#proto=\2\ncn=\3\nport=\5\n#')
    echo ret=$?
    eval $a
    #export proto cn port
}

c() {
    if [[ "$@" =~ ^((udp|tcp)://)?([0-9a-zA-Z\.]+)(:([0-9]+))?$ ]]; then 
        proto=${BASH_REMATCH[2]};
        cn=${BASH_REMATCH[3]};
        port=${BASH_REMATCH[5]};
    else
        echo "Did not match"
    fi
}

#b $@
c $@

echo "proto: $proto"
echo "cn: $cn"
echo "port: $port"