Upgrade all opkg packages

opkg_upgrade_all.sh

#!/bin/sh

MAX_UPDATE_ATTEMPTS=5
MAX_UPGRADE_ATTEMPTS=3

_restart() {
        echo "Restart uhttpd and rpcd..."
        /etc/init.d/uhttpd restart
        /etc/init.d/rpcd restart
}

attempt=${MAX_UPDATE_ATTEMPTS}
while [ ${attempt} -gt 0 ]
do
        echo "Run opkg update, attempt $((${MAX_UPDATE_ATTEMPTS}-${attempt}+1)) of ${MAX_UPDATE_ATTEMPTS}..."
        opkg update >/dev/null 2>&1
        if [ $? -eq 0 ]; then
                echo "Done"
                break
        else
                echo "ERROR: Command opkg update failed."
                sleep 2
        fi
        attempt=$(($attempt-1))
done

NUM_UPGRADABLE=$(opkg list-upgradable 2>/dev/null | wc -l)
if [ ${NUM_UPGRADABLE} -ne 0 ]; then
        echo "Number of upgradable packages is ${NUM_UPGRADABLE}"
        attempt=${MAX_UPGRADE_ATTEMPTS}
        while [ ${attempt} -gt 0 ]
        do
                echo "Run opkg upgrade, attempt $((${MAX_UPGRADE_ATTEMPTS}-${attempt}+1)) of ${MAX_UPGRADE_ATTEMPTS}..."
                opkg list-upgradable | cut -f 1 -d ' ' | xargs opkg upgrade
                if [ $? -eq 0 ]; then                                              
                        _restart
                        break
                else                                                                   
                        echo "ERROR: Upgrade not completed."
                        sleep 2
                fi
                attempt=$(($attempt-1))
        done
else
        echo "No packages need upgrade. Exit..."
        exit 0
fi