only set a read deadline when the keep-alive value is positive (#83)

broker/client.go

@@ -121,6 +121,7 @@ func (c *client) readLoop() {
 			return
 		default:
 			//add read timeout
+			if keepAlive > 0 {
 				if err := nc.SetReadDeadline(time.Now().Add(timeOut)); err != nil {
 					log.Error("set read timeout error: ", zap.Error(err), zap.String("ClientID", c.info.clientID))
 					msg := &Message{
@@ -130,6 +131,7 @@ func (c *client) readLoop() {
 					b.SubmitWork(c.info.clientID, msg)
 					return
 				}
+			}
 
 			packet, err := packets.ReadPacket(nc)
 			if err != nil {