only do a update if DNS entry is outdated

actions/dynamicdns

@@ -269,23 +269,26 @@ doGetWANIP()
 # this function is called via cronjob
 doUpdate()
 {
+    dnsentry=$(nslookup ${host}|tail -n2|grep A|sed s/[^0-9.]//g)
+    if [ "${dnsentry}" =  "${wanip}" ];then
+        return
+    fi
     if [ ! -z ${server} ];then
         start-stop-daemon -S -x ${UPDATE_TOOL} -m -p ${PIDFILE} -- -c ${cfgfile}
     fi
-
     if [ ! -z ${updateurl} ];then
         doReplaceVars
         if [ "${basicauth}" = "enabled" ];then
-            local wgetoptions=" --user $user --password $pass "
+            local wgetoptions=" --user ${user} --password ${pass} "
         fi
         if [ "${ignoreCertError}" = "enabled" ];then
             local wgetoptions=" --no-check-certificate "
         fi
 
-        $WGET ${wgetoptions} "${updateurl}"
+        ${WGET} ${wgetoptions} "${updateurl}"
         # ToDo: check the returning text from WEB Server. User need to give expected string.
-        if [ $? -eq 0 ];then
-            ${0} success $wanip
+        if [ ${?} -eq 0 ];then
+            ${0} success ${wanip}
         else
             ${0} failed
         fi