unbound: bugfix init race condition invalid FQDN

options 'add_local_fqdn' and 'add_wan_fqdn' can be affected
by race conditions when they are at level 4. Interface name
may not be returned by network tools. The conf file has bad
record formats and Unbound just will not load. Detect this
and fall back to only the host FQDN (level 3).

squash: improve documentation wording and format codes.

Signed-off-by: Eric Luehrsen <ericluehrsen@hotmail.com>

net/unbound/files/unbound.sh

@@ -115,7 +115,6 @@ create_interface_dns() {
 
   if [ "$ignore" -gt 0 ] ; then
     mode="$UNBOUND_D_WAN_FQDN"
-
   else
     mode="$UNBOUND_D_LAN_FQDN"
   fi
@@ -128,8 +127,15 @@ create_interface_dns() {
     ;;
 
   4)
-    mode_ptr="$if_fqdn"
-    names="$if_fqdn  $host_fqdn  $UNBOUND_TXT_HOSTNAME"
+    if [ -z "$ifdashname" ] ; then
+      # race conditions at init can rarely cause a blank device return
+      # the record format is invalid and Unbound won't load the conf file
+      mode_ptr="$host_fqdn"
+      names="$host_fqdn  $UNBOUND_TXT_HOSTNAME"
+    else
+      mode_ptr="$if_fqdn"
+      names="$if_fqdn  $host_fqdn  $UNBOUND_TXT_HOSTNAME"
+    fi
     ;;
 
   *)
@@ -297,14 +303,14 @@ unbound_mkdir() {
     fi
   fi
 
-  
+
   if [ -f $UNBOUND_KEYFILE.keep ] ; then
     # root.key.keep is reused if newest
     cp -u $UNBOUND_KEYFILE.keep $UNBOUND_KEYFILE
     rm -f $UNBOUND_KEYFILE.keep
   fi
-  
-  
+
+
   # Ensure access and prepare to jail
   chown -R unbound:unbound $UNBOUND_VARDIR
   chmod 775 $UNBOUND_VARDIR