chainntnfs/neutrinonotify: track best block hash

chainntnfs/neutrinonotify/neutrino.go

@@ -44,8 +44,8 @@ type NeutrinoNotifier struct {
 	started int32 // To be used atomically.
 	stopped int32 // To be used atomically.
 
-	heightMtx  sync.RWMutex
+	bestBlockMtx sync.RWMutex
-	bestHeight uint32
+	bestBlock    chainntnfs.BlockEpoch
 
 	p2pNode   *neutrino.ChainService
 	chainView *neutrino.Rescan
@@ -126,10 +126,12 @@ func (n *NeutrinoNotifier) Start() error {
 	if err != nil {
 		return err
 	}
-	n.bestHeight = uint32(startingPoint.Height)
+	n.bestBlock.Hash = &startingPoint.Hash
+	n.bestBlock.Height = startingPoint.Height
+
 	n.txNotifier = chainntnfs.NewTxNotifier(
-		n.bestHeight, chainntnfs.ReorgSafetyLimit, n.confirmHintCache,
+		uint32(n.bestBlock.Height), chainntnfs.ReorgSafetyLimit,
-		n.spendHintCache,
+		n.confirmHintCache, n.spendHintCache,
 	)
 
 	// Next, we'll create our set of rescan options. Currently it's
@@ -334,9 +336,9 @@ out:
 				chainntnfs.Log.Infof("New block epoch subscription")
 				n.blockEpochClients[msg.epochID] = msg
 				if msg.bestBlock != nil {
-					n.heightMtx.Lock()
+					n.bestBlockMtx.Lock()
-					bestHeight := int32(n.bestHeight)
+					bestHeight := n.bestBlock.Height
-					n.heightMtx.Unlock()
+					n.bestBlockMtx.Unlock()
 					missedBlocks, err :=
 						chainntnfs.GetClientMissedBlocks(
 							n.chainConn, msg.bestBlock,
@@ -365,7 +367,7 @@ out:
 		case item := <-n.chainUpdates.ChanOut():
 			update := item.(*filteredBlock)
 			if update.connect {
-				n.heightMtx.Lock()
+				n.bestBlockMtx.Lock()
 				// Since neutrino has no way of knowing what
 				// height to rewind to in the case of a reorged
 				// best known height, there is no point in
@@ -374,27 +376,24 @@ out:
 				// the other notifiers do when they receive
 				// a new connected block. Therefore, we just
 				// compare the heights.
-				if update.height != n.bestHeight+1 {
+				if update.height != uint32(n.bestBlock.Height+1) {
 					// Handle the case where the notifier
 					// missed some blocks from its chain
 					// backend
 					chainntnfs.Log.Infof("Missed blocks, " +
 						"attempting to catch up")
-					bestBlock := chainntnfs.BlockEpoch{
+
-						Height: int32(n.bestHeight),
-						Hash:   nil,
-					}
 					_, missedBlocks, err :=
 						chainntnfs.HandleMissedBlocks(
 							n.chainConn,
 							n.txNotifier,
-							bestBlock,
+							n.bestBlock,
 							int32(update.height),
 							false,
 						)
 					if err != nil {
 						chainntnfs.Log.Error(err)
-						n.heightMtx.Unlock()
+						n.bestBlockMtx.Unlock()
 						continue
 					}
 
@@ -403,13 +402,13 @@ out:
 							n.getFilteredBlock(block)
 						if err != nil {
 							chainntnfs.Log.Error(err)
-							n.heightMtx.Unlock()
+							n.bestBlockMtx.Unlock()
 							continue out
 						}
 						err = n.handleBlockConnected(filteredBlock)
 						if err != nil {
 							chainntnfs.Log.Error(err)
-							n.heightMtx.Unlock()
+							n.bestBlockMtx.Unlock()
 							continue out
 						}
 					}
@@ -420,42 +419,30 @@ out:
 				if err != nil {
 					chainntnfs.Log.Error(err)
 				}
-				n.heightMtx.Unlock()
+
+				n.bestBlockMtx.Unlock()
 				continue
 			}
 
-			n.heightMtx.Lock()
+			n.bestBlockMtx.Lock()
-			if update.height != uint32(n.bestHeight) {
+			if update.height != uint32(n.bestBlock.Height) {
 				chainntnfs.Log.Infof("Missed disconnected " +
 					"blocks, attempting to catch up")
 			}
-
-			hash, err := n.p2pNode.GetBlockHash(int64(n.bestHeight))
-			if err != nil {
-				chainntnfs.Log.Errorf("Unable to fetch block hash "+
-					"for height %d: %v", n.bestHeight, err)
-				n.heightMtx.Unlock()
-				continue
-			}
-
-			notifierBestBlock := chainntnfs.BlockEpoch{
-				Height: int32(n.bestHeight),
-				Hash:   hash,
-			}
 			newBestBlock, err := chainntnfs.RewindChain(
-				n.chainConn, n.txNotifier, notifierBestBlock,
+				n.chainConn, n.txNotifier, n.bestBlock,
 				int32(update.height-1),
 			)
 			if err != nil {
 				chainntnfs.Log.Errorf("Unable to rewind chain "+
 					"from height %d to height %d: %v",
-					n.bestHeight, update.height-1, err)
+					n.bestBlock.Height, update.height-1, err)
 			}
 
 			// Set the bestHeight here in case a chain rewind
 			// partially completed.
-			n.bestHeight = uint32(newBestBlock.Height)
+			n.bestBlock = newBestBlock
-			n.heightMtx.Unlock()
+			n.bestBlockMtx.Unlock()
 
 		case txUpdate := <-n.txUpdates.ChanOut():
 			// A new relevant transaction notification has been
@@ -570,6 +557,8 @@ func (n *NeutrinoNotifier) historicalConfDetails(confRequest chainntnfs.ConfRequ
 // handleBlockConnected applies a chain update for a new block. Any watched
 // transactions included this block will processed to either send notifications
 // now or after numConfirmations confs.
+//
+// NOTE: This method must be called with the bestBlockMtx lock held.
 func (n *NeutrinoNotifier) handleBlockConnected(newBlock *filteredBlock) error {
 	// We'll extend the txNotifier's height with the information of this new
 	// block, which will handle all of the notification logic for us.
@@ -588,7 +577,8 @@ func (n *NeutrinoNotifier) handleBlockConnected(newBlock *filteredBlock) error {
 	// registered clients whom have had notifications fulfilled. Before
 	// doing so, we'll make sure update our in memory state in order to
 	// satisfy any client requests based upon the new block.
-	n.bestHeight = newBlock.height
+	n.bestBlock.Hash = &newBlock.hash
+	n.bestBlock.Height = int32(newBlock.height)
 
 	n.notifyBlockEpochs(int32(newBlock.height), &newBlock.hash)
 	return n.txNotifier.NotifyHeight(newBlock.height)
@@ -730,9 +720,9 @@ func (n *NeutrinoNotifier) RegisterSpendNtfn(outpoint *wire.OutPoint,
 	// to fetch the UTXO from the chain. If we're behind, then we may miss a
 	// notification dispatch.
 	for {
-		n.heightMtx.RLock()
+		n.bestBlockMtx.RLock()
-		currentHeight := n.bestHeight
+		currentHeight := uint32(n.bestBlock.Height)
-		n.heightMtx.RUnlock()
+		n.bestBlockMtx.RUnlock()
 
 		if currentHeight >= historicalDispatch.StartHeight {
 			break

chainntnfs/neutrinonotify/neutrino_dev.go

@@ -89,7 +89,8 @@ func (n *NeutrinoNotifier) UnsafeStart(bestHeight int32,
 
 	// Run notificationDispatcher after setting the notifier's best height
 	// to avoid a race condition.
-	n.bestHeight = uint32(bestHeight)
+	n.bestBlock.Hash = bestHash
+	n.bestBlock.Height = bestHeight
 
 	n.wg.Add(1)
 	go n.notificationDispatcher()