Fix new green signals bug caused by old trav_lzbdata, and callback loop in signalling formspec

advtrains/lzb.lua

@@ -69,6 +69,7 @@ local function resolve_latest_lzbdata(ckp, index)
 		if ckpi.index <= index and ckpi.lzbdata then
 			return ckpi.lzbdata
 		end
+		i=i-1
 	end
 	return {}
 end
@@ -197,6 +198,8 @@ function advtrains.lzb_invalidate_ahead(train, start_idx)
 			end
 		end
 		train.lzb.trav_index = idx
+		-- FIX reset trav_lzbdata (look_ahead fetches these when required)
+		train.lzb.trav_lzbdata = nil
 		-- re-apply all checkpoints to path_speed
 		train.path_speed = {}
 		for _,ckp in ipairs(train.lzb.checkpoints) do

advtrains/occupation.lua

@@ -196,7 +196,6 @@ function o.get_trains_over(ppos)
 	local r = {}
 	local i = 1
 	while t[i] do
-		local train = advtrains.trains[t[i]]
 		local idx = t[i+1]
 		r[t[i]] = idx
 		i = i + 2

advtrains_interlocking/tcb_ts_ui.lua

@@ -558,7 +558,7 @@ local sig_pselidx = {}
 -- Players having a signalling form open
 local p_open_sig_form = {}
 
-function advtrains.interlocking.show_signalling_form(sigd, pname, sel_rte)
+function advtrains.interlocking.show_signalling_form(sigd, pname, sel_rte, called_from_form_update)
 	if not minetest.check_player_privs(pname, "train_operator") then
 		minetest.chat_send_player(pname, "Insufficient privileges to use this!")
 		return
@@ -651,7 +651,10 @@ function advtrains.interlocking.show_signalling_form(sigd, pname, sel_rte)
 	p_open_sig_form[pname] = sigd
 	
 	-- always a good idea to update the signal aspect
-	advtrains.interlocking.update_signal_aspect(tcbs)
+	if not called_from_form_update then
+	-- FIX prevent a callback loop
+		advtrains.interlocking.update_signal_aspect(tcbs)
+	end
 end
 
 function advtrains.interlocking.update_player_forms(sigd)
@@ -763,7 +766,7 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 			tcbs.route_auto = false
 		end
 		
-		advtrains.interlocking.show_signalling_form(sigd, pname, sel_rte)
+		advtrains.interlocking.show_signalling_form(sigd, pname, sel_rte, true)
 		return
 	end