gluon-l3roamd: init: dynamically configure mesh interfaces gracefully during reload

This patch makes use of the new feature in l3roamd to gracefully
add, remove and list the mesh interfaces that are currently in use. This
helps when changing mesh interfaces often - a characteristic of the
wireguard protocol implementation as in the previous behavior all local
clients are dropped when adjusting mesh interfaces.

package/gluon-l3roamd/files/etc/init.d/gluon-l3roamd

@@ -5,10 +5,39 @@ START=55
 USE_PROCD=1
 PROG=/usr/sbin/l3roamd
 
+echotol3roamd() {
+	local count=0
+	local line="$1"
+	while ! (echo -e "$line" | uc /var/run/l3roamd.sock >/dev/null 2>&1)
+	do
+		sleep 1
+		echo retrying to connect to l3roamd in PID $$, waited ${count}s >&2
+		count=$((count+1))
+	done
+	return 0
+}
+
+
+
+reload_service() {
+	for i in $(ubus call network.interface dump | jsonfilter -e "@.interface[@.proto='gluon_mesh' && @.up=true].device")
+	do
+		echotol3roamd "add_meshif $i"
+	done
+
+	for i in $(echotol3roamd "get_meshifs"| jsonfilter -e "@.mesh_interfaces[@]")
+	do
+		if ! ubus call network.interface dump | jsonfilter -e "@.interface[@.proto='gluon_mesh' && @.up=true].device"|grep -q $i
+		then
+			echotol3roamd "del_meshif $i"
+		fi
+	done
+}
+
 start_service () {
 	local interfaces=$(
-		for dev in $(gluon-list-mesh-interfaces); do echo " -m $dev"; done
+	for dev in $(gluon-list-mesh-interfaces); do echo " -m $dev"; done
-		[ "$(ifstatus local_node | jsonfilter -e '@.up')" = 'true' ] && echo ' -i local-node'
+	[ "$(ifstatus local_node | jsonfilter -e '@.up')" = 'true' ] && echo ' -i local-node'
 	)
 	/sbin/sysctl -w net.ipv6.neigh.default.gc_thresh1=2
 	/sbin/sysctl -w net.ipv4.neigh.default.gc_thresh1=2