Move script_run_callbacks to Lua

builtin/misc_register.lua

@@ -314,6 +314,45 @@ minetest.register_item(":", {
 	groups = {not_in_creative_inventory=1},
 })
 
+
+function minetest.run_callbacks(callbacks, mode, ...)
+	assert(type(callbacks) == "table")
+	local cb_len = #callbacks
+	if cb_len == 0 then
+		if mode == 2 or mode == 3 then
+			return true
+		elseif mode == 4 or mode == 5 then
+			return false
+		end
+	end
+	local ret = nil
+	for i = 1, cb_len do
+		local cb_ret = callbacks[i](...)
+
+		if mode == 0 and i == 1 then
+			ret = cb_ret
+		elseif mode == 1 and i == cb_len then
+			ret = cb_ret
+		elseif mode == 2 then
+			if not cb_ret or i == 1 then
+				ret = cb_ret
+			end
+		elseif mode == 3 then
+			if cb_ret then
+				return cb_ret
+			end
+			ret = cb_ret
+		elseif mode == 4 then
+			if (cb_ret and not ret) or i == 1 then
+				ret = cb_ret
+			end
+		elseif mode == 5 and cb_ret then
+			return cb_ret
+		end
+	end
+	return ret
+end
+
 --
 -- Callback registration
 --