[blocked-4507]: Update rust-lightning to use default_value_vec

Update to be able to write vectors of HTLCLocator for PaymentForwarded.
Note that we still don't expect to receive multiple outgoing HTLCs
because trampoline has not yet been enabled, but we lay the groundwork
here.

Author: carlaKC

Cargo.toml

@@ -172,15 +172,15 @@ harness = false
 #vss-client-ng = { path = "../vss-client" }
 #vss-client-ng = { git = "https://github.com/lightningdevkit/vss-client", branch = "main" }
 #
-#[patch."https://github.com/lightningdevkit/rust-lightning"]
-#lightning = { path = "../rust-lightning/lightning" }
-#lightning-types = { path = "../rust-lightning/lightning-types" }
-#lightning-invoice = { path = "../rust-lightning/lightning-invoice" }
-#lightning-net-tokio = { path = "../rust-lightning/lightning-net-tokio" }
-#lightning-persister = { path = "../rust-lightning/lightning-persister" }
-#lightning-background-processor = { path = "../rust-lightning/lightning-background-processor" }
-#lightning-rapid-gossip-sync = { path = "../rust-lightning/lightning-rapid-gossip-sync" }
-#lightning-block-sync = { path = "../rust-lightning/lightning-block-sync" }
-#lightning-transaction-sync = { path = "../rust-lightning/lightning-transaction-sync" }
-#lightning-liquidity = { path = "../rust-lightning/lightning-liquidity" }
-#lightning-macros = { path = "../rust-lightning/lightning-macros" }
+[patch."https://github.com/lightningdevkit/rust-lightning"]
+lightning = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc", features = ["std"] }
+lightning-types = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc" }
+lightning-invoice = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc", features = ["std"] }
+lightning-net-tokio = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc" }
+lightning-persister = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc", features = ["tokio"] }
+lightning-background-processor = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc" }
+lightning-rapid-gossip-sync = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc" }
+lightning-block-sync = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc", features = ["rest-client", "rpc-client", "tokio"] }
+lightning-transaction-sync = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc", features = ["esplora-async-https", "time", "electrum-rustls-ring"] }
+lightning-liquidity = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc", features = ["std"] }
+lightning-macros = { git = "https://github.com/carlakc/rust-lightning", rev = "62fde7a019b2d6a696efb7120be1d548efb031cc" }

src/event.rs

@@ -18,10 +18,9 @@ use lightning::events::bump_transaction::BumpTransactionEvent;
 #[cfg(not(feature = "uniffi"))]
 use lightning::events::PaidBolt12Invoice;
 use lightning::events::{
-	ClosureReason, Event as LdkEvent, FundingInfo, PaymentFailureReason, PaymentPurpose,
-	ReplayEvent,
+	ClosureReason, Event as LdkEvent, FundingInfo, HTLCLocator as LdkHtlcLocator,
+	PaymentFailureReason, PaymentPurpose, ReplayEvent,
 };
-use lightning::impl_writeable_tlv_based_enum;
 use lightning::ln::channelmanager::PaymentId;
 use lightning::ln::types::ChannelId;
 use lightning::routing::gossip::NodeId;
@@ -32,6 +31,7 @@ use lightning::util::config::{
 use lightning::util::errors::APIError;
 use lightning::util::persist::KVStore;
 use lightning::util::ser::{Readable, ReadableArgs, Writeable, Writer};
+use lightning::{impl_writeable_tlv_based, impl_writeable_tlv_based_enum};
 use lightning_liquidity::lsps2::utils::compute_opening_fee;
 use lightning_types::payment::{PaymentHash, PaymentPreimage};
 
@@ -61,6 +61,40 @@ use crate::{
 	UserChannelId,
 };
 
+/// Identifies the channel and counterparty that a HTLC was processed with.
+#[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "uniffi", derive(uniffi::Record))]
+pub struct HTLCLocator {
+	/// The channel that the HTLC was sent or received on.
+	pub channel_id: ChannelId,
+	/// The `user_channel_id` for the channel.
+	///
+	/// Will only be `None` for events serialized with LDK Node v0.3.0 or prior, or if the
+	/// payment was settled via an on-chain transaction.
+	pub user_channel_id: Option<UserChannelId>,
+	/// The node id of the counterparty for this HTLC.
+	///
+	/// This is only `None` for HTLCs received prior to LDK Node v0.5 or for events serialized by
+	/// versions prior to v0.5.
+	pub node_id: Option<PublicKey>,
+}
+
+impl_writeable_tlv_based!(HTLCLocator, {
+	(1, channel_id, required),
+	(3, user_channel_id, option),
+	(5, node_id, option),
+});
+
+impl From<LdkHtlcLocator> for HTLCLocator {
+	fn from(value: LdkHtlcLocator) -> Self {
+		HTLCLocator {
+			channel_id: value.channel_id,
+			user_channel_id: value.user_channel_id.map(|u| UserChannelId(u)),
+			node_id: value.node_id,
+		}
+	}
+}
+
 /// An event emitted by [`Node`], which should be handled by the user.
 ///
 /// [`Node`]: [`crate::Node`]
@@ -128,29 +162,14 @@ pub enum Event {
 	},
 	/// A payment has been forwarded.
 	PaymentForwarded {
-		/// The channel id of the incoming channel between the previous node and us.
-		prev_channel_id: ChannelId,
-		/// The channel id of the outgoing channel between the next node and us.
-		next_channel_id: ChannelId,
-		/// The `user_channel_id` of the incoming channel between the previous node and us.
-		///
-		/// Will only be `None` for events serialized with LDK Node v0.3.0 or prior.
-		prev_user_channel_id: Option<UserChannelId>,
-		/// The `user_channel_id` of the outgoing channel between the next node and us.
-		///
-		/// This will be `None` if the payment was settled via an on-chain transaction. See the
-		/// caveat described for the `total_fee_earned_msat` field.
-		next_user_channel_id: Option<UserChannelId>,
-		/// The node id of the previous node.
-		///
-		/// This is only `None` for HTLCs received prior to LDK Node v0.5 or for events serialized by
-		/// versions prior to v0.5.
-		prev_node_id: Option<PublicKey>,
-		/// The node id of the next node.
-		///
-		/// This is only `None` for HTLCs received prior to LDK Node v0.5 or for events serialized by
-		/// versions prior to v0.5.
-		next_node_id: Option<PublicKey>,
+		/// The set of incoming HTLCs that were forwarded to our node. Contains a single HTLC for
+		/// source-routed payments, and may contain multiple HTLCs when we acted as a trampoline
+		/// router.
+		prev_htlcs: Vec<HTLCLocator>,
+		/// The set of outgoing HTLCs forwarded by our node. Contains a single HTLC for regular
+		/// source-routed payments, and may contain multiple HTLCs when we acted as a trampoline
+		/// router.
+		next_htlcs: Vec<HTLCLocator>,
 		/// The total fee, in milli-satoshis, which was earned as a result of the payment.
 		///
 		/// Note that if we force-closed the channel over which we forwarded an HTLC while the HTLC
@@ -323,16 +342,27 @@ impl_writeable_tlv_based_enum!(Event,
 		(7, custom_records, optional_vec),
 	},
 	(7, PaymentForwarded) => {
-		(0, prev_channel_id, required),
-		(1, prev_node_id, option),
-		(2, next_channel_id, required),
-		(3, next_node_id, option),
-		(4, prev_user_channel_id, option),
-		(6, next_user_channel_id, option),
+		// Legacy fields: read from old data, never written.
+		(0, legacy_prev_channel_id, (legacy, ChannelId, |_| Ok(()), |_: &Event| None::<Option<ChannelId>>)),
+		(1, legacy_prev_node_id, (legacy, PublicKey, |_| Ok(()), |_: &Event| None::<Option<PublicKey>>)),
+		(2, legacy_next_channel_id, (legacy, ChannelId, |_| Ok(()), |_: &Event| None::<Option<ChannelId>>)),
+		(3, legacy_next_node_id, (legacy, PublicKey, |_| Ok(()), |_: &Event| None::<Option<PublicKey>>)),
+		(4, legacy_prev_user_channel_id, (legacy, u128, |_| Ok(()), |_: &Event| None::<Option<u128>>)),
+		(6, legacy_next_user_channel_id, (legacy, u128, |_| Ok(()), |_: &Event| None::<Option<u128>>)),
 		(8, total_fee_earned_msat, option),
 		(10, skimmed_fee_msat, option),
 		(12, claim_from_onchain_tx, required),
 		(14, outbound_amount_forwarded_msat, option),
+		(15, prev_htlcs, (default_value_vec, vec![HTLCLocator {
+			channel_id: legacy_prev_channel_id.ok_or(lightning::ln::msgs::DecodeError::InvalidValue)?,
+			user_channel_id: legacy_prev_user_channel_id.map(UserChannelId),
+			node_id: legacy_prev_node_id,
+		}])),
+		(17, next_htlcs, (default_value_vec, vec![HTLCLocator {
+			channel_id: legacy_next_channel_id.ok_or(lightning::ln::msgs::DecodeError::InvalidValue)?,
+			user_channel_id: legacy_next_user_channel_id.map(UserChannelId),
+			node_id: legacy_next_node_id,
+		}])),
 	},
 	(8, SplicePending) => {
 		(1, channel_id, required),
@@ -1400,9 +1430,6 @@ where
 				// reporting the first HTLC in each vec.
 				debug_assert_eq!(prev_htlcs.len(), 1, "unexpected number of prev_htlcs");
 				debug_assert_eq!(next_htlcs.len(), 1, "unexpected number of next_htlcs");
-				let prev_htlc = prev_htlcs
-					.first()
-					.expect("we expect at least one prev_htlc for PaymentForwarded");
 				let next_htlc = next_htlcs
 					.first()
 					.expect("we expect at least one next_htlc for PaymentForwarded");
@@ -1415,12 +1442,8 @@ where
 				}
 
 				let event = Event::PaymentForwarded {
-					prev_channel_id: prev_htlc.channel_id,
-					next_channel_id: next_htlc.channel_id,
-					prev_user_channel_id: prev_htlc.user_channel_id.map(UserChannelId),
-					next_user_channel_id: next_htlc.user_channel_id.map(UserChannelId),
-					prev_node_id: prev_htlc.node_id,
-					next_node_id: next_htlc.node_id,
+					prev_htlcs: prev_htlcs.into_iter().map(HTLCLocator::from).collect(),
+					next_htlcs: next_htlcs.into_iter().map(HTLCLocator::from).collect(),
 					total_fee_earned_msat,
 					skimmed_fee_msat,
 					claim_from_onchain_tx,