f Don't track spent_outputs

Author: tnull

lightning-transaction-sync/src/esplora.rs

@@ -143,7 +143,7 @@ where
 				}
 
 				match maybe_await!(self.get_confirmed_transactions(&sync_state)) {
-					Ok((confirmed_txs, spent_outputs)) => {
+					Ok(confirmed_txs) => {
 						// Double-check the tip hash. If if it changed, a reorg happened since
 						// we started syncing and we need to restart last-minute.
 						let check_tip_hash = maybe_await!(self.client.get_tip_hash())?;
@@ -156,7 +156,6 @@ where
 							&mut sync_state,
 							&confirmables,
 							confirmed_txs,
-							spent_outputs,
 						);
 					}
 					Err(InternalError::Inconsistency) => {
@@ -202,7 +201,6 @@ where
 
 	fn sync_confirmed_transactions(
 		&self, sync_state: &mut SyncState, confirmables: &Vec<&(dyn Confirm + Sync + Send)>, confirmed_txs: Vec<ConfirmedTx>,
-		spent_outputs: HashSet<WatchedOutput>,
 	) {
 		for ctx in confirmed_txs {
 			for c in confirmables {
@@ -214,15 +212,17 @@ where
 			}
 
 			sync_state.watched_transactions.remove(&ctx.tx.txid());
+			
+			for input in &ctx.tx.input {
+				sync_state.watched_outputs.remove(&input.previous_output);
+			}
 		}
-
-		sync_state.watched_outputs = &sync_state.watched_outputs - &spent_outputs;
 	}
 
 	#[maybe_async]
 	fn get_confirmed_transactions(
 		&self, sync_state: &SyncState,
-	) -> Result<(Vec<ConfirmedTx>, HashSet<WatchedOutput>), InternalError> {
+	) -> Result<Vec<ConfirmedTx>, InternalError> {
 
 		// First, check the confirmation status of registered transactions as well as the
 		// status of dependent transactions of registered outputs.
@@ -235,10 +235,7 @@ where
 			}
 		}
 
-		// Remember all registered outputs that have been spent.
-		let mut spent_outputs = HashSet::new();
-
-		for output in &sync_state.watched_outputs {
+		for (_, output) in &sync_state.watched_outputs {
 			if let Some(output_status) = maybe_await!(self.client
 				.get_output_status(&output.outpoint.txid, output.outpoint.index as u64))?
 			{
@@ -252,8 +249,6 @@ where
 							))?
 						{
 							confirmed_txs.push(confirmed_tx);
-							spent_outputs.insert(output.clone());
-							continue;
 						}
 					}
 				}
@@ -266,7 +261,7 @@ where
 			tx1.block_height.cmp(&tx2.block_height).then_with(|| tx1.pos.cmp(&tx2.pos))
 		});
 
-		Ok((confirmed_txs, spent_outputs))
+		Ok(confirmed_txs)
 	}
 
 	#[maybe_async]
@@ -378,6 +373,6 @@ where
 
 	fn register_output(&self, output: WatchedOutput) {
 		let mut locked_queue = self.queue.lock().unwrap();
-		locked_queue.outputs.insert(output);
+		locked_queue.outputs.insert(output.outpoint.into_bitcoin_outpoint(), output);
 	}
 }

lightning-transaction-sync/src/types.rs

@@ -1,6 +1,7 @@
 use lightning::chain::WatchedOutput;
-use bitcoin::{Txid, BlockHash, Transaction, BlockHeader};
-use std::collections::HashSet;
+use bitcoin::{Txid, BlockHash, Transaction, BlockHeader, OutPoint};
+
+use std::collections::{HashSet, HashMap};
 
 
 // Represents the current state.
@@ -10,7 +11,7 @@ pub(crate) struct SyncState {
 	pub watched_transactions: HashSet<Txid>,
 	// Outputs that were previously processed, but must not be forgotten yet as
 	// as we still need to monitor any spends on-chain.
-	pub watched_outputs: HashSet<WatchedOutput>,
+	pub watched_outputs: HashMap<OutPoint, WatchedOutput>,
 	// The tip hash observed during our last sync.
 	pub last_sync_hash: Option<BlockHash>,
 	// Indicates whether we need to resync, e.g., after encountering an error.
@@ -21,7 +22,7 @@ impl SyncState {
 	pub fn new() -> Self {
 		Self {
 			watched_transactions: HashSet::new(),
-			watched_outputs: HashSet::new(),
+			watched_outputs: HashMap::new(),
 			last_sync_hash: None,
 			pending_sync: false,
 		}
@@ -34,14 +35,14 @@ pub(crate) struct FilterQueue {
 	// Transactions that were registered via the `Filter` interface and have to be processed.
 	pub transactions: HashSet<Txid>,
 	// Outputs that were registered via the `Filter` interface and have to be processed.
-	pub outputs: HashSet<WatchedOutput>,
+	pub outputs: HashMap<OutPoint, WatchedOutput>,
 }
 
 impl FilterQueue {
 	pub fn new() -> Self {
 		Self {
 			transactions: HashSet::new(),
-			outputs: HashSet::new(),
+			outputs: HashMap::new(),
 		}
 	}