-- Create a file named by_ip/''ip_addess''.cap with all ip traffic of each ip host. (works for tshark only)
-- Dump files are created for both source and destination hosts
do
	local dir = "by_tlli"
	local dumpers = {}
	local function init_listener()
		local udp_port_table = DissectorTable.get("udp.port")
		local gprs_ns_dis = Dissector.get("gprs_ns")
		udp_port_table:add(23000,gprs_ns_dis)

		local field_tlli = Field.new("bssgp.tlli")
		local tap = Listener.new("ip", "udp.port == 23000")

		-- we will be called once for every IP Header.
		-- If there's more than one IP header in a given packet we'll dump the packet once per every header
		function tap.packet(pinfo,tvb,ip)
			local ttli = field_tlli()
			if not ttli then
				return
			end

			local ttli_str = tostring(ttli)
			ttli_dmp = dumpers[ttli_str]
			if not ttli_dmp then
				print("Creating TLLI " .. tostring(ttli) .. " " .. ttli_str)
				ttli_dmp = Dumper.new_for_current(dir .. "/" .. ttli_str .. ".pcap")
				dumpers[ttli_str] = ttli_dmp
			end
			ttli_dmp:dump_current()
			ttli_dmp:flush()
		end
		function tap.draw()
			for ttli,dumper in pairs(dumpers) do
				 dumper:flush()
			end
		end
		function tap.reset()
			for ttli,dumper in pairs(dumpers) do
				 dumper:close()
			end
			dumpers = {}
		end
	end
	init_listener()
end