Improvement Request for Static IP Configuration File Parsing

[NightowlKr]

Issue:
script file"/etc/init.d/S30eth" fails to handle comments in "/boot/eth.nodhcp"

Suggested fix:
Add a filter to ignore comments in the /boot/eth.nodhcp file, using:

cat /boot/eth.nodhcp | grep -v '^#' | while read inet gw

Proposed code file "/etc/init.d/S30eth" change:

start() {
    printf "start ethernet: "
    if [ -e /boot/eth.nodhcp ]
    then
        [ -e /boot/eth.nodhcp ] &&
            cat /boot/eth.nodhcp | grep -v '^#'  | while read inet gw
            do
                addr=${inet%/*}
                netid=${inet#*/}
                [ -z $gw ] &&
                gw=$( echo $addr| ( IFS='.' read a b c d; echo $((
                    (((((($a<<8)+$b)<<8)+$c)<<8)+$d)
                        & (((1<<$netid)-1)<<(32-$netid))
                    ))
                )) &&
                gw=$(($gw>>24&0xff)).$(($gw>>16&0xff)).$(($gw>>8&0xff)).$((1+( $gw>>0&0xff )))

                arping -Dqc2 -Ieth0 $addr || continue
                ip a add $inet brd + dev eth0
                ip r add default via $gw dev eth0
                cat > /etc/resolve.conf << EOF
nameserver $gw
nameserver 8.8.8.8
nameserver 114.114.114.114
EOF
                break
            done &&
            ip a show dev eth0|grep inet || (
                udhcpc -i eth0 -t 3 -T 1 -A 5 -b -p /run/udhcpc.eth0.pid &>/dev/null
                ip a show dev eth0|grep inet
            ) || (
                # failed to apply dynamic addr, need a available static addr to visit the LAN
                inet=$RESERVE_INET
                addr=${inet%/*}
                ip a add $inet brd + dev eth0
            ) || exit 1
    else
        (udhcpc -i eth0 -t 10 -T 1 -A 5 -b -p /run/udhcpc.eth0.pid) &
    fi

    echo "OK"
}

[archont94]

I think it would be even better to add yq binary and read configs from YAML files.