gossip: Refactoring message handling and removed redundant timers

We were firing off the wakeup timers all over the place, out of fear
that we would be triggering two concurrent broadcasts. This is not
really the case since the wakeup calls are idempotent. This also
allows us not to differentiate between triggering a broadcast on a
local peer or on a proxied peer.

lightningd/gossip/gossip.c

@@ -74,6 +74,8 @@ struct peer {
 	bool local;
 };
 
+static void wake_pkt_out(struct peer *peer);
+
 static void destroy_peer(struct peer *peer)
 {
 	list_del_from(&peer->daemon->peers, &peer->list);
@@ -98,9 +100,28 @@ static struct peer *setup_new_peer(struct daemon *daemon, const u8 *msg)
 	peer->proxy_msg_out = tal_arr(peer, u8*, 0);
 	list_add_tail(&daemon->peers, &peer->list);
 	tal_add_destructor(peer, destroy_peer);
+	wake_pkt_out(peer);
 	return peer;
 }
 
+static void handle_gossip_msg(struct routing_state *rstate, u8 *msg)
+{
+	int t = fromwire_peektype(msg);
+	switch(t) {
+	case WIRE_CHANNEL_ANNOUNCEMENT:
+		handle_channel_announcement(rstate, msg, tal_count(msg));
+		break;
+
+	case WIRE_NODE_ANNOUNCEMENT:
+		handle_node_announcement(rstate, msg, tal_count(msg));
+		break;
+
+	case WIRE_CHANNEL_UPDATE:
+		handle_channel_update(rstate, msg, tal_count(msg));
+		break;
+	}
+}
+
 static struct io_plan *peer_msgin(struct io_conn *conn,
 				  struct peer *peer, u8 *msg)
 {
@@ -114,15 +135,9 @@ static struct io_plan *peer_msgin(struct io_conn *conn,
 		return io_close(conn);
 
 	case WIRE_CHANNEL_ANNOUNCEMENT:
-		handle_channel_announcement(peer->daemon->rstate, msg, tal_count(msg));
-		return peer_read_message(conn, &peer->pcs, peer_msgin);
-
 	case WIRE_NODE_ANNOUNCEMENT:
-		handle_node_announcement(peer->daemon->rstate, msg, tal_count(msg));
-		return peer_read_message(conn, &peer->pcs, peer_msgin);
-
 	case WIRE_CHANNEL_UPDATE:
-		handle_channel_update(peer->daemon->rstate, msg, tal_count(msg));
+		handle_gossip_msg(peer->daemon->rstate, msg);
 		return peer_read_message(conn, &peer->pcs, peer_msgin);
 
 	case WIRE_INIT:
@@ -180,6 +195,8 @@ static struct io_plan *pkt_out(struct io_conn *conn, struct peer *peer);
 static void wake_pkt_out(struct peer *peer)
 {
 	peer->gossip_sync = true;
+	new_reltimer(&peer->daemon->timers, peer, time_from_sec(30),
+		     wake_pkt_out, peer);
 	io_wake(peer);
 }
 
@@ -193,8 +210,6 @@ static struct io_plan *peer_dump_gossip(struct io_conn *conn, struct peer *peer)
 				      &peer->broadcast_index);
 
 	if (!next) {
-		new_reltimer(&peer->daemon->timers, peer, time_from_sec(30),
-			     wake_pkt_out, peer);
 		/* Going to wake up in pkt_out since we mix time based and
 		 * message based wakeups */
 		return io_out_wait(conn, peer, pkt_out, peer);
@@ -262,8 +277,6 @@ static struct io_plan *client_dump_gossip(struct io_conn *conn, struct peer *pee
 				      &peer->broadcast_index);
 
 	if (!next) {
-		new_reltimer(&peer->daemon->timers, peer, time_from_sec(30),
-			     wake_pkt_out, peer);
 		return io_out_wait(conn, peer, client_pkt_out, peer);
 	} else {
 		return io_write_wire(conn, next->payload, client_dump_gossip, peer);
@@ -283,8 +296,6 @@ static struct io_plan *client_pkt_out(struct io_conn *conn, struct peer *peer)
 
 	if (peer->local) {
 		/* Not our turn, the local loop is taking care of broadcasts */
-		new_reltimer(&peer->daemon->timers, peer, time_from_sec(30),
-			     wake_pkt_out, peer);
 		/* Going to wake up in pkt_out since we mix time based and
 		 * message based wakeups */
 		return io_out_wait(conn, peer, client_pkt_out, peer);