Emit SpliceLocked event

Once both parties have exchanged splice_locked messages, the splice
funding is ready for use. Emit an event to the user indicating as much.

Author: jkczyz

lightning/src/events/mod.rs

@@ -1353,10 +1353,13 @@ pub enum Event {
 		/// Will be `None` for channels created prior to LDK version 0.0.122.
 		channel_type: Option<ChannelTypeFeatures>,
 	},
-	/// Used to indicate that a channel with the given `channel_id` is ready to
-	/// be used. This event is emitted either when the funding transaction has been confirmed
-	/// on-chain, or, in case of a 0conf channel, when both parties have confirmed the channel
-	/// establishment.
+	/// Used to indicate that a channel with the given `channel_id` is ready to be used. This event
+	/// is emitted when
+	/// - the initial funding transaction has been confirmed on-chain to an acceptable depth
+	///   according to both parties (i.e., `channel_ready` messages were exchanged),
+	/// - a splice funding transaction has been confirmed on-chain to an acceptable depth according
+	///   to both parties (i.e., `splice_locked` messages were exchanged), or,
+	/// - in case of a 0conf channel, when both parties have confirmed the channel establishment.
 	///
 	/// # Failure Behavior and Persistence
 	/// This event will eventually be replayed after failures-to-handle (i.e., the event handler

lightning/src/ln/channel.rs

@@ -2440,8 +2440,8 @@ where
 	// We track whether we already emitted a `FundingTxBroadcastSafe` event.
 	funding_tx_broadcast_safe_event_emitted: bool,
 
-	// We track whether we already emitted a `ChannelReady` event.
-	channel_ready_event_emitted: bool,
+	// We track whether we already emitted an initial `ChannelReady` event.
+	initial_channel_ready_event_emitted: bool,
 
 	/// Some if we initiated to shut down the channel.
 	local_initiated_shutdown: Option<()>,
@@ -3288,7 +3288,7 @@ where
 
 			channel_pending_event_emitted: false,
 			funding_tx_broadcast_safe_event_emitted: false,
-			channel_ready_event_emitted: false,
+			initial_channel_ready_event_emitted: false,
 
 			channel_keys_id,
 
@@ -3531,7 +3531,7 @@ where
 
 			channel_pending_event_emitted: false,
 			funding_tx_broadcast_safe_event_emitted: false,
-			channel_ready_event_emitted: false,
+			initial_channel_ready_event_emitted: false,
 
 			channel_keys_id,
 
@@ -3959,14 +3959,14 @@ where
 		self.channel_pending_event_emitted = true;
 	}
 
-	// Checks whether we should emit a `ChannelReady` event.
-	pub(crate) fn should_emit_channel_ready_event(&mut self) -> bool {
-		self.is_usable() && !self.channel_ready_event_emitted
+	// Checks whether we should emit an initial `ChannelReady` event.
+	pub(crate) fn should_emit_initial_channel_ready_event(&mut self) -> bool {
+		self.is_usable() && !self.initial_channel_ready_event_emitted
 	}
 
 	// Remembers that we already emitted a `ChannelReady` event.
-	pub(crate) fn set_channel_ready_event_emitted(&mut self) {
-		self.channel_ready_event_emitted = true;
+	pub(crate) fn set_initial_channel_ready_event_emitted(&mut self) {
+		self.initial_channel_ready_event_emitted = true;
 	}
 
 	// Remembers that we already emitted a `FundingTxBroadcastSafe` event.
@@ -12050,7 +12050,7 @@ where
 			{ Some(self.context.holder_max_htlc_value_in_flight_msat) } else { None };
 
 		let channel_pending_event_emitted = Some(self.context.channel_pending_event_emitted);
-		let channel_ready_event_emitted = Some(self.context.channel_ready_event_emitted);
+		let initial_channel_ready_event_emitted = Some(self.context.initial_channel_ready_event_emitted);
 		let funding_tx_broadcast_safe_event_emitted = Some(self.context.funding_tx_broadcast_safe_event_emitted);
 
 		// `user_id` used to be a single u64 value. In order to remain backwards compatible with
@@ -12094,7 +12094,7 @@ where
 			(17, self.context.announcement_sigs_state, required),
 			(19, self.context.latest_inbound_scid_alias, option),
 			(21, self.context.outbound_scid_alias, required),
-			(23, channel_ready_event_emitted, option),
+			(23, initial_channel_ready_event_emitted, option),
 			(25, user_id_high_opt, option),
 			(27, self.context.channel_keys_id, required),
 			(28, holder_max_accepted_htlcs, option),
@@ -12403,7 +12403,7 @@ where
 		let mut latest_inbound_scid_alias = None;
 		let mut outbound_scid_alias = 0u64;
 		let mut channel_pending_event_emitted = None;
-		let mut channel_ready_event_emitted = None;
+		let mut initial_channel_ready_event_emitted = None;
 		let mut funding_tx_broadcast_safe_event_emitted = None;
 
 		let mut user_id_high_opt: Option<u64> = None;
@@ -12458,7 +12458,7 @@ where
 			(17, announcement_sigs_state, required),
 			(19, latest_inbound_scid_alias, option),
 			(21, outbound_scid_alias, required),
-			(23, channel_ready_event_emitted, option),
+			(23, initial_channel_ready_event_emitted, option),
 			(25, user_id_high_opt, option),
 			(27, channel_keys_id, required),
 			(28, holder_max_accepted_htlcs, option),
@@ -12758,7 +12758,7 @@ where
 
 				funding_tx_broadcast_safe_event_emitted: funding_tx_broadcast_safe_event_emitted.unwrap_or(false),
 				channel_pending_event_emitted: channel_pending_event_emitted.unwrap_or(true),
-				channel_ready_event_emitted: channel_ready_event_emitted.unwrap_or(true),
+				initial_channel_ready_event_emitted: initial_channel_ready_event_emitted.unwrap_or(true),
 
 				channel_keys_id,
 

lightning/src/ln/channelmanager.rs

@@ -3355,9 +3355,9 @@ macro_rules! emit_channel_pending_event {
 	};
 }
 
-macro_rules! emit_channel_ready_event {
+macro_rules! emit_initial_channel_ready_event {
 	($locked_events: expr, $channel: expr) => {
-		if $channel.context.should_emit_channel_ready_event() {
+		if $channel.context.should_emit_initial_channel_ready_event() {
 			debug_assert!($channel.context.channel_pending_event_emitted());
 			$locked_events.push_back((
 				events::Event::ChannelReady {
@@ -3368,7 +3368,7 @@ macro_rules! emit_channel_ready_event {
 				},
 				None,
 			));
-			$channel.context.set_channel_ready_event_emitted();
+			$channel.context.set_initial_channel_ready_event_emitted();
 		}
 	};
 }
@@ -8155,7 +8155,7 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 		{
 			let mut pending_events = self.pending_events.lock().unwrap();
 			emit_channel_pending_event!(pending_events, channel);
-			emit_channel_ready_event!(pending_events, channel);
+			emit_initial_channel_ready_event!(pending_events, channel);
 		}
 
 		(htlc_forwards, decode_update_add_htlcs)
@@ -9182,7 +9182,7 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 
 					{
 						let mut pending_events = self.pending_events.lock().unwrap();
-						emit_channel_ready_event!(pending_events, chan);
+						emit_initial_channel_ready_event!(pending_events, chan);
 					}
 
 					Ok(())
@@ -10161,6 +10161,14 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 					if !chan.has_pending_splice() {
 						let mut short_to_chan_info = self.short_to_chan_info.write().unwrap();
 						insert_short_channel_id!(short_to_chan_info, chan);
+
+						let mut pending_events = self.pending_events.lock().unwrap();
+						pending_events.push_back((events::Event::ChannelReady {
+							channel_id: chan.context.channel_id(),
+							user_channel_id: chan.context.get_user_id(),
+							counterparty_node_id: chan.context.get_counterparty_node_id(),
+							channel_type: chan.funding.get_channel_type().clone(),
+						}, None));
 					}
 
 					if let Some(announcement_sigs) = announcement_sigs_opt {
@@ -12267,6 +12275,14 @@ where
 										if !funded_channel.has_pending_splice() {
 											let mut short_to_chan_info = self.short_to_chan_info.write().unwrap();
 											insert_short_channel_id!(short_to_chan_info, funded_channel);
+
+											let mut pending_events = self.pending_events.lock().unwrap();
+											pending_events.push_back((events::Event::ChannelReady {
+												channel_id: funded_channel.context.channel_id(),
+												user_channel_id: funded_channel.context.get_user_id(),
+												counterparty_node_id: funded_channel.context.get_counterparty_node_id(),
+												channel_type: funded_channel.funding.get_channel_type().clone(),
+											}, None));
 										}
 
 										pending_msg_events.push(MessageSendEvent::SendSpliceLocked {
@@ -12279,7 +12295,7 @@ where
 
 								{
 									let mut pending_events = self.pending_events.lock().unwrap();
-									emit_channel_ready_event!(pending_events, funded_channel);
+									emit_initial_channel_ready_event!(pending_events, funded_channel);
 								}
 
 								if let Some(height) = height_opt {