Remove funding script return value from ChannelMonitor::get_funding_txo

It's not needed except for one place where we can just access the field
directly, so we can avoid the allocation on each call. For API
consumers, they may still access the funding script via
`ChannelMonitor::get_funding_script`.

Author: wpaulino

lightning/src/chain/chainmonitor.rs

@@ -342,7 +342,7 @@ where C::Target: chain::Filter,
 			// `ChannelMonitorUpdate` after a channel persist for a channel with the same
 			// `latest_update_id`.
 			let _pending_monitor_updates = monitor_state.pending_monitor_updates.lock().unwrap();
-			let funding_txo = monitor.get_funding_txo().0;
+			let funding_txo = monitor.get_funding_txo();
 			match self.persister.update_persisted_channel(funding_txo, None, monitor) {
 				ChannelMonitorUpdateStatus::Completed =>
 					log_trace!(logger, "Finished syncing Channel Monitor for channel {} for block-data",
@@ -516,7 +516,7 @@ where C::Target: chain::Filter,
 			// Completed event.
 			return Ok(());
 		}
-		let funding_txo = monitor_data.monitor.get_funding_txo().0;
+		let funding_txo = monitor_data.monitor.get_funding_txo();
 		self.pending_monitor_events.lock().unwrap().push((funding_txo, channel_id, vec![MonitorEvent::Completed {
 			funding_txo,
 			channel_id,
@@ -535,7 +535,7 @@ where C::Target: chain::Filter,
 		let monitors = self.monitors.read().unwrap();
 		let monitor = &monitors.get(&channel_id).unwrap().monitor;
 		let counterparty_node_id = monitor.get_counterparty_node_id();
-		let funding_txo = monitor.get_funding_txo().0;
+		let funding_txo = monitor.get_funding_txo();
 		self.pending_monitor_events.lock().unwrap().push((funding_txo, channel_id, vec![MonitorEvent::Completed {
 			funding_txo,
 			channel_id,
@@ -642,7 +642,7 @@ where C::Target: chain::Filter,
 				have_monitors_to_prune = true;
 			}
 			if needs_persistence {
-				self.persister.update_persisted_channel(monitor_holder.monitor.get_funding_txo().0, None, &monitor_holder.monitor);
+				self.persister.update_persisted_channel(monitor_holder.monitor.get_funding_txo(), None, &monitor_holder.monitor);
 			}
 		}
 		if have_monitors_to_prune {
@@ -655,7 +655,7 @@ where C::Target: chain::Filter,
 						"Archiving fully resolved ChannelMonitor for channel ID {}",
 						channel_id
 					);
-					self.persister.archive_persisted_channel(monitor_holder.monitor.get_funding_txo().0);
+					self.persister.archive_persisted_channel(monitor_holder.monitor.get_funding_txo());
 					false
 				} else {
 					true
@@ -769,7 +769,7 @@ where C::Target: chain::Filter,
 		log_trace!(logger, "Got new ChannelMonitor for channel {}", log_funding_info!(monitor));
 		let update_id = monitor.get_latest_update_id();
 		let mut pending_monitor_updates = Vec::new();
-		let persist_res = self.persister.persist_new_channel(monitor.get_funding_txo().0, &monitor);
+		let persist_res = self.persister.persist_new_channel(monitor.get_funding_txo(), &monitor);
 		match persist_res {
 			ChannelMonitorUpdateStatus::InProgress => {
 				log_info!(logger, "Persistence of new ChannelMonitor for channel {} in progress", log_funding_info!(monitor));
@@ -825,7 +825,7 @@ where C::Target: chain::Filter,
 				let update_res = monitor.update_monitor(update, &self.broadcaster, &self.fee_estimator, &self.logger);
 
 				let update_id = update.update_id;
-				let funding_txo = monitor.get_funding_txo().0;
+				let funding_txo = monitor.get_funding_txo();
 				let persist_res = if update_res.is_err() {
 					// Even if updating the monitor returns an error, the monitor's state will
 					// still be changed. Therefore, we should persist the updated monitor despite the error.
@@ -878,7 +878,7 @@ where C::Target: chain::Filter,
 		for monitor_state in self.monitors.read().unwrap().values() {
 			let monitor_events = monitor_state.monitor.get_and_clear_pending_monitor_events();
 			if monitor_events.len() > 0 {
-				let monitor_funding_txo = monitor_state.monitor.get_funding_txo().0;
+				let monitor_funding_txo = monitor_state.monitor.get_funding_txo();
 				let monitor_channel_id = monitor_state.monitor.channel_id();
 				let counterparty_node_id = monitor_state.monitor.get_counterparty_node_id();
 				pending_monitor_events.push((monitor_funding_txo, monitor_channel_id, monitor_events, counterparty_node_id));

lightning/src/chain/channelmonitor.rs

@@ -1574,8 +1574,13 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 	}
 
 	/// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
-	pub fn get_funding_txo(&self) -> (OutPoint, ScriptBuf) {
-		self.inner.lock().unwrap().get_funding_txo().clone()
+	pub fn get_funding_txo(&self) -> OutPoint {
+		self.inner.lock().unwrap().get_funding_txo()
+	}
+
+	/// Gets the funding script of the channel this ChannelMonitor is monitoring for.
+	pub fn get_funding_script(&self) -> ScriptBuf {
+		self.inner.lock().unwrap().get_funding_script()
 	}
 
 	/// Gets the channel_id of the channel this ChannelMonitor is monitoring for.
@@ -1599,8 +1604,8 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 	{
 		let lock = self.inner.lock().unwrap();
 		let logger = WithChannelMonitor::from_impl(logger, &*lock, None);
-		log_trace!(&logger, "Registering funding outpoint {}", &lock.get_funding_txo().0);
-		filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
+		log_trace!(&logger, "Registering funding outpoint {}", &lock.get_funding_txo());
+		filter.register_tx(&lock.funding_info.0.txid, &lock.funding_info.1);
 		for (txid, outputs) in lock.get_outputs_to_watch().iter() {
 			for (index, script_pubkey) in outputs.iter() {
 				assert!(*index <= u16::MAX as u32);
@@ -2061,7 +2066,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 					"Thought we were done claiming funds, but claimable_balances now has entries");
 				log_error!(logger,
 					"WARNING: LDK thought it was done claiming all the available funds in the ChannelMonitor for channel {}, but later decided it had more to claim. This is potentially an important bug in LDK, please report it at https://github.com/lightningdevkit/rust-lightning/issues/new",
-					inner.get_funding_txo().0);
+					inner.get_funding_txo());
 				inner.balances_empty_height = None;
 				(false, true)
 			},
@@ -2070,7 +2075,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 				// None. It is set to the current block height.
 				log_debug!(logger,
 					"ChannelMonitor funded at {} is now fully resolved. It will become archivable in {} blocks",
-					inner.get_funding_txo().0, ARCHIVAL_DELAY_BLOCKS);
+					inner.get_funding_txo(), ARCHIVAL_DELAY_BLOCKS);
 				inner.balances_empty_height = Some(current_height);
 				(false, true)
 			},
@@ -3296,8 +3301,12 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
 		self.latest_update_id
 	}
 
-	fn get_funding_txo(&self) -> &(OutPoint, ScriptBuf) {
-		&self.funding_info
+	fn get_funding_txo(&self) -> OutPoint {
+		self.funding_info.0
+	}
+
+	fn get_funding_script(&self) -> ScriptBuf {
+		self.funding_info.1.clone()
 	}
 
 	pub fn channel_id(&self) -> ChannelId {

lightning/src/ln/channelmanager.rs

@@ -8131,7 +8131,7 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 			},
 			hash_map::Entry::Vacant(e) => {
 				let mut outpoint_to_peer_lock = self.outpoint_to_peer.lock().unwrap();
-				match outpoint_to_peer_lock.entry(monitor.get_funding_txo().0) {
+				match outpoint_to_peer_lock.entry(monitor.get_funding_txo()) {
 					hash_map::Entry::Occupied(_) => {
 						fail_chan!("The funding_created message had the same funding_txid as an existing channel - funding is not possible");
 					},
@@ -13365,7 +13365,7 @@ where
 					updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast: true }],
 					channel_id: Some(monitor.channel_id()),
 				};
-				let funding_txo = monitor.get_funding_txo().0;
+				let funding_txo = monitor.get_funding_txo();
 				if let Some(counterparty_node_id) = monitor.get_counterparty_node_id() {
 					let update = BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
 						counterparty_node_id,
@@ -13576,7 +13576,7 @@ where
 			) => { {
 				let mut max_in_flight_update_id = 0;
 				$chan_in_flight_upds.retain(|upd| upd.update_id > $monitor.get_latest_update_id());
-				let funding_txo = $monitor.get_funding_txo().0;
+				let funding_txo = $monitor.get_funding_txo();
 				for update in $chan_in_flight_upds.iter() {
 					log_trace!($logger, "Replaying ChannelMonitorUpdate {} for {}channel {}",
 						update.update_id, $channel_info_log, &$monitor.channel_id());
@@ -13741,7 +13741,7 @@ where
 			// We only rebuild the pending payments map if we were most recently serialized by
 			// 0.0.102+
 			for (_, monitor) in args.channel_monitors.iter() {
-				let counterparty_opt = outpoint_to_peer.get(&monitor.get_funding_txo().0);
+				let counterparty_opt = outpoint_to_peer.get(&monitor.get_funding_txo());
 				if counterparty_opt.is_none() {
 					for (htlc_source, (htlc, _)) in monitor.get_pending_or_resolved_outbound_htlcs() {
 						let logger = WithChannelMonitor::from(&args.logger, monitor, Some(htlc.payment_hash));
@@ -13821,7 +13821,7 @@ where
 									// `ChannelMonitor` is removed.
 									let compl_action =
 										EventCompletionAction::ReleaseRAAChannelMonitorUpdate {
-											channel_funding_outpoint: monitor.get_funding_txo().0,
+											channel_funding_outpoint: monitor.get_funding_txo(),
 											channel_id: monitor.channel_id(),
 											counterparty_node_id: path.hops[0].pubkey,
 										};
@@ -13934,7 +13934,7 @@ where
 									// channel_id -> peer map entry).
 									counterparty_opt.is_none(),
 									counterparty_opt.cloned().or(monitor.get_counterparty_node_id()),
-									monitor.get_funding_txo().0, monitor.channel_id()))
+									monitor.get_funding_txo(), monitor.channel_id()))
 							} else { None }
 						} else {
 							// If it was an outbound payment, we've handled it above - if a preimage

lightning/src/util/persist.rs

@@ -356,8 +356,8 @@ where
 			(&*entropy_source, &*signer_provider),
 		) {
 			Ok((block_hash, channel_monitor)) => {
-				if channel_monitor.get_funding_txo().0.txid != txid
-					|| channel_monitor.get_funding_txo().0.index != index
+				if channel_monitor.get_funding_txo().txid != txid
+					|| channel_monitor.get_funding_txo().index != index
 				{
 					return Err(io::Error::new(
 						io::ErrorKind::InvalidData,
@@ -617,8 +617,8 @@ where
 			(&*self.entropy_source, &*self.signer_provider),
 		) {
 			Ok((blockhash, channel_monitor)) => {
-				if channel_monitor.get_funding_txo().0.txid != outpoint.txid
-					|| channel_monitor.get_funding_txo().0.index != outpoint.index
+				if channel_monitor.get_funding_txo().txid != outpoint.txid
+					|| channel_monitor.get_funding_txo().index != outpoint.index
 				{
 					log_error!(
 						self.logger,
@@ -1219,7 +1219,7 @@ mod tests {
 					// check that when we read it, we got the right update id
 					assert_eq!(mon.get_latest_update_id(), $expected_update_id);
 
-					let monitor_name = MonitorName::from(mon.get_funding_txo().0);
+					let monitor_name = MonitorName::from(mon.get_funding_txo());
 					assert_eq!(
 						persister_0
 							.kv_store
@@ -1238,7 +1238,7 @@ mod tests {
 				assert_eq!(persisted_chan_data_1.len(), 1);
 				for (_, mon) in persisted_chan_data_1.iter() {
 					assert_eq!(mon.get_latest_update_id(), $expected_update_id);
-					let monitor_name = MonitorName::from(mon.get_funding_txo().0);
+					let monitor_name = MonitorName::from(mon.get_funding_txo());
 					assert_eq!(
 						persister_1
 							.kv_store
@@ -1433,7 +1433,7 @@ mod tests {
 		// Get the monitor and make a fake stale update at update_id=1 (lowest height of an update possible)
 		let persisted_chan_data = persister_0.read_all_channel_monitors_with_updates().unwrap();
 		let (_, monitor) = &persisted_chan_data[0];
-		let monitor_name = MonitorName::from(monitor.get_funding_txo().0);
+		let monitor_name = MonitorName::from(monitor.get_funding_txo());
 		persister_0
 			.kv_store
 			.write(