add new socket message WARNING

lualib/socket.lua

@@ -133,6 +133,25 @@ socket_message[6] = function(id, size, data, address)
 	s.callback(str, address)
 end
 
+local function default_warning(id, size)
+	local s = socket_pool[id]
+		local last = s.warningsize or 0
+		if last + 64 < size then	-- if size increase 64K
+			s.warningsize = size
+			skynet.error(string.format("WARNING: %d K bytes need to send out (fd = %d)", size, id))
+		end
+		s.warningsize = size
+end
+
+-- SKYNET_SOCKET_TYPE_WARNING
+socket_message[7] = function(id, size)
+	local s = socket_pool[id]
+	if s then
+		local warning = s.warning or default_warning
+		warning(id, size)
+	end
+end
+
 skynet.register_protocol {
 	name = "socket",
 	id = skynet.PTYPE_SOCKET,	-- PTYPE_SOCKET = 6
@@ -404,4 +423,10 @@ end
 socket.sendto = assert(driver.udp_send)
 socket.udp_address = assert(driver.udp_address)
 
+function socket.warning(id, callback)
+	local obj = socket_pool[id]
+	assert(obj)
+	obj.warning = callback
+end
+
 return socket