libknot/processing: moved packet parsing out of overlay_consume()

the overlay may be used for cached data now, and it's not okay to reparse
it if not needed or wanted

src/knot/server/tcp-handler.c

@@ -144,6 +144,7 @@ static int tcp_handle(tcp_context_t *tcp, int fd,
 	knot_overlay_add(&tcp->overlay, NS_PROC_QUERY, &param);
 
 	/* Input packet. */
+	(void) knot_pkt_parse(query, 0);
 	int state = knot_overlay_consume(&tcp->overlay, query);
 
 	/* Resolve until NOOP or finished. */

src/knot/server/udp-handler.c

@@ -134,6 +134,7 @@ void udp_handle(udp_context_t *udp, int fd, struct sockaddr_storage *ss,
 	knot_overlay_add(&udp->overlay, NS_PROC_QUERY, &param);
 
 	/* Input packet. */
+	(void) knot_pkt_parse(query, 0);
 	int state = knot_overlay_consume(&udp->overlay, query);
 
 	/* Process answer. */

src/libknot/processing/overlay.c

@@ -89,8 +89,6 @@ int knot_overlay_consume(struct knot_overlay *overlay, knot_pkt_t *pkt)
 		return overlay->state;
 	}
 
-	knot_pkt_parse(pkt, 0);
-
 	ITERATE_LAYERS(overlay, knot_layer_consume, pkt);
 }
 

src/libknot/processing/requestor.c

@@ -255,6 +255,7 @@ static int request_io(struct knot_requestor *req, struct knot_request *last,
 			return ret;
 		}
 
+		(void) knot_pkt_parse(query, 0);
 		knot_overlay_consume(&req->overlay, resp);
 	}