f only look up node details when relevant, and read addresses more efficiently

Author: arik-so

lightning-rapid-gossip-sync/src/processing.rs

@@ -143,65 +143,66 @@ impl<NG: Deref<Target=NetworkGraph<L>>, L: Deref> RapidGossipSync<NG, L> where L
 				let current_node_id = NodeId::from_pubkey(&current_pubkey);
 				node_ids.push(current_pubkey);
 
-				let mut synthetic_node_announcement = UnsignedNodeAnnouncement {
-					features: NodeFeatures::empty(),
-					timestamp: backdated_timestamp,
-					node_id: current_node_id,
-					rgb: [0, 0, 0],
-					alias: NodeAlias([0u8; 32]),
-					addresses: Vec::new(),
-					excess_address_data: Vec::new(),
-					excess_data: Vec::new(),
-				};
-
-				read_only_network_graph.nodes()
-					.get(&current_node_id)
-					.and_then(|node| node.announcement_info.as_ref())
-					.map(|info| {
-						synthetic_node_announcement.features = info.features().clone();
-						synthetic_node_announcement.rgb = info.rgb().clone();
-						synthetic_node_announcement.alias = info.alias().clone();
-						synthetic_node_announcement.addresses = info.addresses().clone();
-					});
-
-				if has_address_details {
-					let address_count: u8 = Readable::read(read_cursor)?;
-					let mut node_addresses: Vec<SocketAddress> = Vec::new();
-					for address_index in 0..address_count {
-						let current_byte_count: u8 = Readable::read(read_cursor)?;
-						let mut address_reader = FixedLengthReader::new(&mut read_cursor, current_byte_count as u64);
-						let mut address_bytes = Vec::new();
-						address_reader.read_to_end(&mut address_bytes)?;
-
-						let mut address_cursor = io::Cursor::new(&address_bytes);
-						if let Ok(current_address) = Readable::read(&mut address_cursor) {
-							node_addresses.push(current_address);
-						} else {
-							// Do not crash to allow future socket address forwards compatibility
-							log_gossip!(
+
+				if has_address_details || feature_detail_marker > 0 {
+					let mut synthetic_node_announcement = UnsignedNodeAnnouncement {
+						features: NodeFeatures::empty(),
+						timestamp: backdated_timestamp,
+						node_id: current_node_id,
+						rgb: [0, 0, 0],
+						alias: NodeAlias([0u8; 32]),
+						addresses: Vec::new(),
+						excess_address_data: Vec::new(),
+						excess_data: Vec::new(),
+					};
+
+					read_only_network_graph.nodes()
+						.get(&current_node_id)
+						.and_then(|node| node.announcement_info.as_ref())
+						.map(|info| {
+							synthetic_node_announcement.features = info.features().clone();
+							synthetic_node_announcement.rgb = info.rgb().clone();
+							synthetic_node_announcement.alias = info.alias().clone();
+							synthetic_node_announcement.addresses = info.addresses().clone();
+						});
+
+					if has_address_details {
+						let address_count: u8 = Readable::read(read_cursor)?;
+						let mut node_addresses: Vec<SocketAddress> = Vec::new();
+						for address_index in 0..address_count {
+							let current_byte_count: u8 = Readable::read(read_cursor)?;
+							let mut address_reader = FixedLengthReader::new(&mut read_cursor, current_byte_count as u64);
+							if let Ok(current_address) = Readable::read(&mut address_reader) {
+								node_addresses.push(current_address);
+								if address_reader.bytes_remain() {
+									return Err(DecodeError::ShortRead.into());
+								}
+							} else {
+								// Do not crash to allow future socket address forwards compatibility
+								log_gossip!(
 								self.logger,
-								"Failure to parse address at index {} for node ID {}: {:?}",
-								address_index, current_node_id, address_bytes
+								"Failure to parse address at index {} for node ID {}",
+								address_index, current_node_id
 							);
+								address_reader.eat_remaining()?;
+							}
 						}
+						synthetic_node_announcement.addresses = node_addresses;
 					}
-					synthetic_node_announcement.addresses = node_addresses;
-				}
 
-				if feature_detail_marker > 0 {
-					if feature_detail_marker < 7 {
-						let feature_index = (feature_detail_marker - 1) as usize;
-						synthetic_node_announcement.features = default_node_features
-							.get(feature_index)
-							.ok_or(DecodeError::InvalidValue)?
-							.clone();
-					} else {
-						let node_features: NodeFeatures = Readable::read(read_cursor)?;
-						synthetic_node_announcement.features = node_features;
+					if feature_detail_marker > 0 {
+						if feature_detail_marker < 7 {
+							let feature_index = (feature_detail_marker - 1) as usize;
+							synthetic_node_announcement.features = default_node_features
+								.get(feature_index)
+								.ok_or(DecodeError::InvalidValue)?
+								.clone();
+						} else {
+							let node_features: NodeFeatures = Readable::read(read_cursor)?;
+							synthetic_node_announcement.features = node_features;
+						}
 					}
-				}
 
-				if feature_detail_marker > 0 || has_address_details {
 					node_modifications.push(synthetic_node_announcement);
 				}