From c61da07516bfddad7850ec7767a8e5ea362852c2 Mon Sep 17 00:00:00 2001
From: Robert Habermeier <rphmeier@gmail.com>
Date: Wed, 31 Aug 2016 14:28:56 +0200
Subject: [PATCH] always process trie death row on commit, add more tracing

---
 ethcore/src/block.rs       |  2 +-
 util/src/trie/triedbmut.rs | 32 ++++++++++++++++++++------------
 2 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/ethcore/src/block.rs b/ethcore/src/block.rs
index 784e71dc0..d3b4ac168 100644
--- a/ethcore/src/block.rs
+++ b/ethcore/src/block.rs
@@ -498,7 +498,7 @@ pub fn enact(
 	{
 		if ::log::max_log_level() >= ::log::LogLevel::Trace {
 			let s = try!(State::from_existing(db.boxed_clone(), parent.state_root().clone(), engine.account_start_nonce(), factories.clone()));
-			trace!("enact(): root={}, author={}, author_balance={}\n", s.root(), header.author(), s.balance(&header.author()));
+			trace!(target: "enact", "num={}, root={}, author={}, author_balance={}\n", header.number(), s.root(), header.author(), s.balance(&header.author()));
 		}
 	}
 
diff --git a/util/src/trie/triedbmut.rs b/util/src/trie/triedbmut.rs
index ca5fb015f..8d3d7d3d3 100644
--- a/util/src/trie/triedbmut.rs
+++ b/util/src/trie/triedbmut.rs
@@ -56,11 +56,11 @@ impl From<H256> for NodeHandle {
 	}
 }
 
-fn empty_children() -> [Option<NodeHandle>; 16] {
-	[
+fn empty_children() -> Box<[Option<NodeHandle>; 16]> {
+	Box::new([
 		None, None, None, None, None, None, None, None,
 		None, None, None, None, None, None, None, None,
-	]
+	])
 }
 
 /// Node types in the Trie.
@@ -78,7 +78,7 @@ enum Node {
 	/// The child node is always a branch.
 	Extension(Bytes, NodeHandle),
 	/// A branch has up to 16 children and an optional value.
-	Branch([Option<NodeHandle>; 16], Option<Bytes>)
+	Branch(Box<[Option<NodeHandle>; 16]>, Option<Bytes>)
 }
 
 impl Node {
@@ -820,19 +820,19 @@ impl<'a> TrieDBMut<'a> {
 	/// Commit the in-memory changes to disk, freeing their storage and
 	/// updating the state root.
 	pub fn commit(&mut self) {
-		let handle = match self.root_handle() {
-			NodeHandle::Hash(_) => return, // no changes necessary.
-			NodeHandle::InMemory(h) => h,
-		};
-
 		trace!(target: "trie", "Committing trie changes to db.");
 
-		// kill all the nodes on death row.
+		// always kill all the nodes on death row.
 		trace!(target: "trie", "{:?} nodes to remove from db", self.death_row.len());
 		for hash in self.death_row.drain() {
 			self.db.remove(&hash);
 		}
 
+		let handle = match self.root_handle() {
+			NodeHandle::Hash(_) => return, // no changes necessary.
+			NodeHandle::InMemory(h) => h,
+		};
+
 		match self.storage.destroy(handle) {
 			Stored::New(node) => {
 				let root_rlp = node.into_rlp(|child, stream| self.commit_node(child, stream));
@@ -906,21 +906,29 @@ impl<'a> TrieMut for TrieDBMut<'a> {
 			return self.remove(key);
 		}
 
+		trace!(target: "trie", "insert: key={:?}, value={:?}", key.pretty(), value.pretty());
+
 		let root_handle = self.root_handle();
-		let (new_handle, _) = try!(self.insert_at(root_handle, NibbleSlice::new(key), value.to_owned()));
+		let (new_handle, changed) = try!(self.insert_at(root_handle, NibbleSlice::new(key), value.to_owned()));
+
+		trace!(target: "trie", "insert: altered trie={}", changed);
 		self.root_handle = NodeHandle::InMemory(new_handle);
 
 		Ok(())
 	}
 
 	fn remove(&mut self, key: &[u8]) -> super::Result<()> {
+		trace!(target: "trie", "remove: key={:?}", key.pretty());
+
 		let root_handle = self.root_handle();
 		let key = NibbleSlice::new(key);
 		match try!(self.remove_at(root_handle, key)) {
-			Some((handle, _)) => {
+			Some((handle, changed)) => {
+				trace!(target: "trie", "remove: altered trie={}", changed);
 				self.root_handle = NodeHandle::InMemory(handle);
 			}
 			None => {
+				trace!(target: "trie", "remove: obliterated trie");
 				self.root_handle = NodeHandle::Hash(SHA3_NULL_RLP);
 				*self.root = SHA3_NULL_RLP;
 			}