gossip_store: avoid gratuitous copy on load.

Doesn't make measurable difference, but an obvious optimization.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

gossipd/gossip_store.c

@@ -327,7 +327,7 @@ void gossip_store_load(struct routing_state *rstate, struct gossip_store *gs)
 							       &gossip_msg,
 							       &satoshis)) {
 			if (!routing_add_channel_announcement(rstate,
-							      gossip_msg,
+							      take(gossip_msg),
 							      satoshis)) {
 				bad = "Bad channel_announcement";
 				goto truncate;
@@ -335,14 +335,16 @@ void gossip_store_load(struct routing_state *rstate, struct gossip_store *gs)
 			stats[0]++;
 		} else if (fromwire_gossip_store_channel_update(msg, msg,
 								&gossip_msg)) {
-			if (!routing_add_channel_update(rstate, gossip_msg)) {
+			if (!routing_add_channel_update(rstate,
+							take(gossip_msg))) {
 				bad = "Bad channel_update";
 				goto truncate;
 			}
 			stats[1]++;
 		} else if (fromwire_gossip_store_node_announcement(msg, msg,
 								   &gossip_msg)) {
-			if (!routing_add_node_announcement(rstate, gossip_msg)) {
+			if (!routing_add_node_announcement(rstate,
+							   take(gossip_msg))) {
 				bad = "Bad node_announcement";
 				goto truncate;
 			}

gossipd/routing.c

@@ -889,6 +889,10 @@ bool routing_add_channel_announcement(struct routing_state *rstate,
 	struct pubkey bitcoin_key_1;
 	struct pubkey bitcoin_key_2;
 
+	/* Make sure we own msg, even if we don't save it. */
+	if (taken(msg))
+		tal_steal(tmpctx, msg);
+
 	if (!fromwire_channel_announcement(
 		    tmpctx, msg, &node_signature_1, &node_signature_2,
 		    &bitcoin_signature_1, &bitcoin_signature_2, &features, &chain_hash,
@@ -1228,6 +1232,10 @@ bool routing_add_channel_update(struct routing_state *rstate,
 	struct chan *chan;
 	u8 direction;
 
+	/* Make sure we own msg, even if we don't save it. */
+	if (taken(update))
+		tal_steal(tmpctx, update);
+
 	if (!fromwire_channel_update(update, &signature, &chain_hash,
 				     &short_channel_id, &timestamp,
 				     &message_flags, &channel_flags,
@@ -1499,6 +1507,10 @@ bool routing_add_node_announcement(struct routing_state *rstate, const u8 *msg T
 	u8 *features, *addresses;
 	struct wireaddr *wireaddrs;
 
+	/* Make sure we own msg, even if we don't save it. */
+	if (taken(msg))
+		tal_steal(tmpctx, msg);
+
 	/* Note: validity of node_id is already checked. */
 	if (!fromwire_node_announcement(tmpctx, msg,
 					&signature, &features, &timestamp,