fix: allow fast node to rewind after abnormal shutdown

core/blockchain.go

@@ -411,10 +411,33 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis
 	if err := bc.loadLastState(); err != nil {
 		return nil, err
 	}
+
+	// Load any existing snapshot, regenerating it if loading failed
+	if bc.cacheConfig.SnapshotLimit > 0 {
+		// If the chain was rewound past the snapshot persistent layer (causing
+		// a recovery block number to be persisted to disk), check if we're still
+		// in recovery mode and in that case, don't invalidate the snapshot on a
+		// head mismatch.
+		var recover bool
+
+		head := bc.CurrentBlock()
+		if layer := rawdb.ReadSnapshotRecoveryNumber(bc.db); layer != nil && *layer >= head.Number.Uint64() {
+			log.Warn("Enabling snapshot recovery", "chainhead", head.Number, "diskbase", *layer)
+			recover = true
+		}
+		snapconfig := snapshot.Config{
+			CacheSize:  bc.cacheConfig.SnapshotLimit,
+			Recovery:   recover,
+			NoBuild:    bc.cacheConfig.SnapshotNoBuild,
+			AsyncBuild: !bc.cacheConfig.SnapshotWait,
+		}
+		bc.snaps, _ = snapshot.New(snapconfig, bc.db, bc.triedb, head.Root, int(bc.cacheConfig.TriesInMemory), bc.NoTries())
+	}
+
 	// Make sure the state associated with the block is available, or log out
 	// if there is no available state, waiting for state sync.
 	head := bc.CurrentBlock()
-	if !bc.NoTries() && !bc.HasState(head.Root) {
+	if !bc.HasState(head.Root) {
 		if head.Number.Uint64() == 0 {
 			// The genesis state is missing, which is only possible in the path-based
 			// scheme. This situation occurs when the initial state sync is not finished
@@ -430,7 +453,7 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis
 			if bc.cacheConfig.SnapshotLimit > 0 {
 				diskRoot = rawdb.ReadSnapshotRoot(bc.db)
 			}
-			if bc.triedb.Scheme() == rawdb.PathScheme {
+			if bc.triedb.Scheme() == rawdb.PathScheme && !bc.NoTries() {
 				recoverable, _ := bc.triedb.Recoverable(diskRoot)
 				if !bc.HasState(diskRoot) && !recoverable {
 					diskRoot = bc.triedb.Head()
@@ -511,27 +534,6 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis
 		}
 	}
 
-	// Load any existing snapshot, regenerating it if loading failed
-	if bc.cacheConfig.SnapshotLimit > 0 {
-		// If the chain was rewound past the snapshot persistent layer (causing
-		// a recovery block number to be persisted to disk), check if we're still
-		// in recovery mode and in that case, don't invalidate the snapshot on a
-		// head mismatch.
-		var recover bool
-
-		head := bc.CurrentBlock()
-		if layer := rawdb.ReadSnapshotRecoveryNumber(bc.db); layer != nil && *layer >= head.Number.Uint64() {
-			log.Warn("Enabling snapshot recovery", "chainhead", head.Number, "diskbase", *layer)
-			recover = true
-		}
-		snapconfig := snapshot.Config{
-			CacheSize:  bc.cacheConfig.SnapshotLimit,
-			Recovery:   recover,
-			NoBuild:    bc.cacheConfig.SnapshotNoBuild,
-			AsyncBuild: !bc.cacheConfig.SnapshotWait,
-		}
-		bc.snaps, _ = snapshot.New(snapconfig, bc.db, bc.triedb, head.Root, int(bc.cacheConfig.TriesInMemory), bc.NoTries())
-	}
 	// do options before start any routine
 	for _, option := range options {
 		bc, err = option(bc)
@@ -993,7 +995,7 @@ func (bc *BlockChain) rewindPathHead(head *types.Header, root common.Hash) (*typ
 // then block number zero is returned, indicating that snapshot recovery is disabled
 // and the whole snapshot should be auto-generated in case of head mismatch.
 func (bc *BlockChain) rewindHead(head *types.Header, root common.Hash) (*types.Header, uint64) {
-	if bc.triedb.Scheme() == rawdb.PathScheme {
+	if bc.triedb.Scheme() == rawdb.PathScheme && !bc.NoTries() {
 		return bc.rewindPathHead(head, root)
 	}
 	return bc.rewindHashHead(head, root)