Use the new legacy en/decoding to de/ser ChannelDetails

Allowing us to use `impl_writeable_tlv_based!` again rather than
manually writing the de/ser logic.

Author: TheBlueMatt

lightning/src/ln/channel_state.rs

@@ -15,15 +15,12 @@ use bitcoin::secp256k1::PublicKey;
 
 use crate::chain::chaininterface::{FeeEstimator, LowerBoundedFeeEstimator};
 use crate::chain::transaction::OutPoint;
-use crate::io;
 use crate::ln::channel::ChannelContext;
-use crate::ln::msgs::DecodeError;
 use crate::ln::types::ChannelId;
 use crate::sign::SignerProvider;
 use crate::types::features::{ChannelTypeFeatures, InitFeatures};
 use crate::types::payment::PaymentHash;
 use crate::util::config::ChannelConfig;
-use crate::util::ser::{Readable, Writeable, Writer};
 
 use core::ops::Deref;
 
@@ -549,128 +546,45 @@ impl ChannelDetails {
 	}
 }
 
-impl Writeable for ChannelDetails {
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
-		// `user_channel_id` used to be a single u64 value. In order to remain backwards compatible with
-		// versions prior to 0.0.113, the u128 is serialized as two separate u64 values.
-		let user_channel_id_low = self.user_channel_id as u64;
-		let user_channel_id_high_opt = Some((self.user_channel_id >> 64) as u64);
-		#[allow(deprecated)] // TODO: Remove once balance_msat is removed.
-		{
-			write_tlv_fields!(writer, {
-				(1, self.inbound_scid_alias, option),
-				(2, self.channel_id, required),
-				(3, self.channel_type, option),
-				(4, self.counterparty, required),
-				(5, self.outbound_scid_alias, option),
-				(6, self.funding_txo, option),
-				(7, self.config, option),
-				(8, self.short_channel_id, option),
-				(9, self.confirmations, option),
-				(10, self.channel_value_satoshis, required),
-				(12, self.unspendable_punishment_reserve, option),
-				(14, user_channel_id_low, required),
-				(16, self.next_outbound_htlc_limit_msat, required), // Forwards compatibility for removed balance_msat field.
-				(18, self.outbound_capacity_msat, required),
-				(19, self.next_outbound_htlc_limit_msat, required),
-				(20, self.inbound_capacity_msat, required),
-				(21, self.next_outbound_htlc_minimum_msat, required),
-				(22, self.confirmations_required, option),
-				(24, self.force_close_spend_delay, option),
-				(26, self.is_outbound, required),
-				(28, self.is_channel_ready, required),
-				(30, self.is_usable, required),
-				(32, self.is_announced, required),
-				(33, self.inbound_htlc_minimum_msat, option),
-				(35, self.inbound_htlc_maximum_msat, option),
-				(37, user_channel_id_high_opt, option),
-				(39, self.feerate_sat_per_1000_weight, option),
-				(41, self.channel_shutdown_state, option),
-				(43, self.pending_inbound_htlcs, optional_vec),
-				(45, self.pending_outbound_htlcs, optional_vec),
-			});
-		}
-		Ok(())
-	}
-}
-
-impl Readable for ChannelDetails {
-	fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
-		_init_and_read_len_prefixed_tlv_fields!(reader, {
-			(1, inbound_scid_alias, option),
-			(2, channel_id, required),
-			(3, channel_type, option),
-			(4, counterparty, required),
-			(5, outbound_scid_alias, option),
-			(6, funding_txo, option),
-			(7, config, option),
-			(8, short_channel_id, option),
-			(9, confirmations, option),
-			(10, channel_value_satoshis, required),
-			(12, unspendable_punishment_reserve, option),
-			(14, user_channel_id_low, required),
-			(16, _balance_msat, option), // Backwards compatibility for removed balance_msat field.
-			(18, outbound_capacity_msat, required),
-			// Note that by the time we get past the required read above, outbound_capacity_msat will be
-			// filled in, so we can safely unwrap it here.
-			(19, next_outbound_htlc_limit_msat, (default_value, outbound_capacity_msat.0.unwrap() as u64)),
-			(20, inbound_capacity_msat, required),
-			(21, next_outbound_htlc_minimum_msat, (default_value, 0)),
-			(22, confirmations_required, option),
-			(24, force_close_spend_delay, option),
-			(26, is_outbound, required),
-			(28, is_channel_ready, required),
-			(30, is_usable, required),
-			(32, is_announced, required),
-			(33, inbound_htlc_minimum_msat, option),
-			(35, inbound_htlc_maximum_msat, option),
-			(37, user_channel_id_high_opt, option),
-			(39, feerate_sat_per_1000_weight, option),
-			(41, channel_shutdown_state, option),
-			(43, pending_inbound_htlcs, optional_vec),
-			(45, pending_outbound_htlcs, optional_vec),
-		});
-
-		// `user_channel_id` used to be a single u64 value. In order to remain backwards compatible with
-		// versions prior to 0.0.113, the u128 is serialized as two separate u64 values.
-		let user_channel_id_low: u64 = user_channel_id_low.0.unwrap();
-		let user_channel_id = user_channel_id_low as u128
-			+ ((user_channel_id_high_opt.unwrap_or(0 as u64) as u128) << 64);
-
-		let _balance_msat: Option<u64> = _balance_msat;
-
-		Ok(Self {
-			inbound_scid_alias,
-			channel_id: channel_id.0.unwrap(),
-			channel_type,
-			counterparty: counterparty.0.unwrap(),
-			outbound_scid_alias,
-			funding_txo,
-			config,
-			short_channel_id,
-			channel_value_satoshis: channel_value_satoshis.0.unwrap(),
-			unspendable_punishment_reserve,
-			user_channel_id,
-			outbound_capacity_msat: outbound_capacity_msat.0.unwrap(),
-			next_outbound_htlc_limit_msat: next_outbound_htlc_limit_msat.0.unwrap(),
-			next_outbound_htlc_minimum_msat: next_outbound_htlc_minimum_msat.0.unwrap(),
-			inbound_capacity_msat: inbound_capacity_msat.0.unwrap(),
-			confirmations_required,
-			confirmations,
-			force_close_spend_delay,
-			is_outbound: is_outbound.0.unwrap(),
-			is_channel_ready: is_channel_ready.0.unwrap(),
-			is_usable: is_usable.0.unwrap(),
-			is_announced: is_announced.0.unwrap(),
-			inbound_htlc_minimum_msat,
-			inbound_htlc_maximum_msat,
-			feerate_sat_per_1000_weight,
-			channel_shutdown_state,
-			pending_inbound_htlcs: pending_inbound_htlcs.unwrap_or(Vec::new()),
-			pending_outbound_htlcs: pending_outbound_htlcs.unwrap_or(Vec::new()),
-		})
-	}
-}
+impl_writeable_tlv_based!(ChannelDetails, {
+	(1, inbound_scid_alias, option),
+	(2, channel_id, required),
+	(3, channel_type, option),
+	(4, counterparty, required),
+	(5, outbound_scid_alias, option),
+	(6, funding_txo, option),
+	(7, config, option),
+	(8, short_channel_id, option),
+	(9, confirmations, option),
+	(10, channel_value_satoshis, required),
+	(12, unspendable_punishment_reserve, option),
+	// Note that _user_channel_id_low is used below, but rustc warns anyway
+	(14, _user_channel_id_low, (legacy, u64,
+		|us: &ChannelDetails| Some(us.user_channel_id as u64))),
+	(16, _balance_msat, (legacy, u64, |us: &ChannelDetails| Some(us.next_outbound_htlc_limit_msat))),
+	(18, outbound_capacity_msat, required),
+	(19, next_outbound_htlc_limit_msat, (default_value, outbound_capacity_msat)),
+	(20, inbound_capacity_msat, required),
+	(21, next_outbound_htlc_minimum_msat, (default_value, 0)),
+	(22, confirmations_required, option),
+	(24, force_close_spend_delay, option),
+	(26, is_outbound, required),
+	(28, is_channel_ready, required),
+	(30, is_usable, required),
+	(32, is_announced, required),
+	(33, inbound_htlc_minimum_msat, option),
+	(35, inbound_htlc_maximum_msat, option),
+	// Note that _user_channel_id_high is used below, but rustc warns anyway
+	(37, _user_channel_id_high, (legacy, u64,
+		|us: &ChannelDetails| Some((us.user_channel_id >> 64) as u64))),
+	(39, feerate_sat_per_1000_weight, option),
+	(41, channel_shutdown_state, option),
+	(43, pending_inbound_htlcs, optional_vec),
+	(45, pending_outbound_htlcs, optional_vec),
+	(_unused, user_channel_id, (static_value,
+		_user_channel_id_low.unwrap_or(0) as u128 | ((_user_channel_id_high.unwrap_or(0) as u128) << 64)
+	)),
+});
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 /// Further information on the details of the channel shutdown.

lightning/src/util/ser.rs

@@ -413,6 +413,12 @@ impl<T> From<T> for RequiredWrapper<T> {
 		RequiredWrapper(Some(t))
 	}
 }
+impl<T: Clone> Clone for RequiredWrapper<T> {
+	fn clone(&self) -> Self {
+		Self(self.0.clone())
+	}
+}
+impl<T: Copy> Copy for RequiredWrapper<T> {}
 
 /// Wrapper to read a required (non-optional) TLV record that may have been upgraded without
 /// backwards compat.