Merge pull request #1243 from Roasbeef/init-block-index-consistency

blockchain: in initChainState mark ancestors of best tip as valid if …

blockchain/chain.go

@@ -1085,6 +1085,17 @@ func (b *BlockChain) reorganizeChain(detachNodes, attachNodes *list.List) error
 func (b *BlockChain) connectBestChain(node *blockNode, block *btcutil.Block, flags BehaviorFlags) (bool, error) {
 	fastAdd := flags&BFFastAdd == BFFastAdd
 
+	flushIndexState := func() {
+		// Intentionally ignore errors writing updated node status to DB. If
+		// it fails to write, it's not the end of the world. If the block is
+		// valid, we flush in connectBlock and if the block is invalid, the
+		// worst that can happen is we revalidate the block after a restart.
+		if writeErr := b.index.flushToDB(); writeErr != nil {
+			log.Warnf("Error flushing block index changes to disk: %v",
+				writeErr)
+		}
+	}
+
 	// We are extending the main (best) chain with a new block.  This is the
 	// most common case.
 	parentHash := &block.MsgBlock().Header.PrevBlock
@@ -1108,14 +1119,7 @@ func (b *BlockChain) connectBestChain(node *blockNode, block *btcutil.Block, fla
 				return false, err
 			}
 
-			// Intentionally ignore errors writing updated node status to DB. If
-			// it fails to write, it's not the end of the world. If the block is
-			// valid, we flush in connectBlock and if the block is invalid, the
-			// worst that can happen is we revalidate the block after a restart.
-			if writeErr := b.index.flushToDB(); writeErr != nil {
-				log.Warnf("Error flushing block index changes to disk: %v",
-					writeErr)
-			}
+			flushIndexState()
 
 			if err != nil {
 				return false, err
@@ -1140,9 +1144,28 @@ func (b *BlockChain) connectBestChain(node *blockNode, block *btcutil.Block, fla
 		// Connect the block to the main chain.
 		err := b.connectBlock(node, block, view, stxos)
 		if err != nil {
+			// If we got hit with a rule error, then we'll mark
+			// that status of the block as invalid and flush the
+			// index state to disk before returning with the error.
+			if _, ok := err.(RuleError); ok {
+				b.index.SetStatusFlags(
+					node, statusValidateFailed,
+				)
+			}
+
+			flushIndexState()
+
 			return false, err
 		}
 
+		// If this is fast add, or this block node isn't yet marked as
+		// valid, then we'll update its status and flush the state to
+		// disk again.
+		if fastAdd || !b.index.NodeStatus(node).KnownValid() {
+			b.index.SetStatusFlags(node, statusValid)
+			flushIndexState()
+		}
+
 		return true, nil
 	}
 	if fastAdd {

blockchain/chainio.go

@@ -1128,7 +1128,7 @@ func (b *BlockChain) initChainState() error {
 	}
 
 	// Attempt to load the chain state from the database.
-	return b.db.View(func(dbTx database.Tx) error {
+	err = b.db.View(func(dbTx database.Tx) error {
 		// Fetch the stored chain state from the database metadata.
 		// When it doesn't exist, it means the database hasn't been
 		// initialized for use with chain yet, so break out now to allow
@@ -1221,6 +1221,25 @@ func (b *BlockChain) initChainState() error {
 			return err
 		}
 
+		// As a final consistency check, we'll run through all the
+		// nodes which are ancestors of the current chain tip, and mark
+		// them as valid if they aren't already marked as such.  This
+		// is a safe assumption as all the block before the current tip
+		// are valid by definition.
+		for iterNode := tip; iterNode != nil; iterNode = iterNode.parent {
+			// If this isn't already marked as valid in the index, then
+			// we'll mark it as valid now to ensure consistency once
+			// we're up and running.
+			if !iterNode.status.KnownValid() {
+				log.Infof("Block %v (height=%v) ancestor of "+
+					"chain tip not marked as valid, "+
+					"upgrading to valid for consistency",
+					iterNode.hash, iterNode.height)
+
+				b.index.SetStatusFlags(iterNode, statusValid)
+			}
+		}
+
 		// Initialize the state related to the best block.
 		blockSize := uint64(len(blockBytes))
 		blockWeight := uint64(GetBlockWeight(btcutil.NewBlock(&block)))
@@ -1230,6 +1249,14 @@ func (b *BlockChain) initChainState() error {
 
 		return nil
 	})
+	if err != nil {
+		return err
+	}
+
+	// As we might have updated the index after it was loaded, we'll
+	// attempt to flush the index to the DB. This will only result in a
+	// write if the elements are dirty, so it'll usually be a noop.
+	return b.index.flushToDB()
 }
 
 // deserializeBlockRow parses a value in the block index bucket into a block