Merge branch 'master' of github.com:ethcore/parity

.gitmodules

@@ -1,4 +1,4 @@
 [submodule "ethcore/res/ethereum/tests"]
 	path = ethcore/res/ethereum/tests
-	url = git@github.com:ethereum/tests
+	url = https://github.com/ethereum/tests.git
 	branch = develop

README.md

@@ -2,13 +2,15 @@
 
 [![Build Status][travis-image]][travis-url] [![Coverage Status][coveralls-image]][coveralls-url] [![Join the chat at https://gitter.im/trogdoro/xiki][gitter-image]][gitter-url]
 
-[travis-image]: https://travis-ci.com/ethcore/parity.svg?token=DMFvZu71iaTbUYx9UypX&branch=master
+[travis-image]: https://travis-ci.org/ethcore/parity.svg?branch=master
-[travis-url]: https://travis-ci.com/ethcore/parity
+[travis-url]: https://travis-ci.org/ethcore/parity
 [coveralls-image]: https://coveralls.io/repos/github/ethcore/parity/badge.svg?branch=master&t=Fk0OuQ
 [coveralls-url]: https://coveralls.io/r/ethcore/parity?branch=master
 [gitter-image]: https://badges.gitter.im/Join%20Chat.svg
 [gitter-url]: https://gitter.im/ethcore/parity?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge
 
+[Documentation](http://ethcore.github.io/parity/ethcore/index.html)
+
 ### Building from source
 
 ##### Ubuntu 14.04, 15.04, 15.10

ethcore/src/block_queue.rs

@@ -205,6 +205,8 @@ impl BlockQueue {
 		let mut verification = self.verification.lock().unwrap();
 		verification.unverified.clear();
 		verification.verifying.clear();
+		verification.verified.clear();
+		self.processing.write().unwrap().clear();
 	}
 
 	/// Wait for queue to be empty

ethcore/src/client.rs

@@ -67,7 +67,6 @@ impl fmt::Display for BlockChainInfo {
 	}
 }
 
-
 /// Blockchain database client. Owns and manages a blockchain and a block queue.
 pub trait BlockChainClient : Sync + Send {
 	/// Get raw block header data by block header hash.
@@ -155,8 +154,7 @@ impl ClientReport {
 pub struct Client {
 	chain: Arc<RwLock<BlockChain>>,
 	engine: Arc<Box<Engine>>,
-	state_db: Arc<DB>,
+	state_db: Mutex<JournalDB>,
-	state_journal: Mutex<JournalDB>,
 	block_queue: RwLock<BlockQueue>,
 	report: RwLock<ClientReport>,
 	import_lock: Mutex<()>
@@ -209,8 +207,7 @@ impl Client {
 		Ok(Arc::new(Client {
 			chain: chain,
 			engine: engine.clone(),
-			state_db: db.clone(),
+			state_db: Mutex::new(state_db),
-			state_journal: Mutex::new(JournalDB::new_with_arc(db)),
 			block_queue: RwLock::new(BlockQueue::new(engine, message_channel)),
 			report: RwLock::new(Default::default()),
 			import_lock: Mutex::new(()),
@@ -265,7 +262,7 @@ impl Client {
 				}
 			}
 
-			let db = self.state_journal.lock().unwrap().clone();
+			let db = self.state_db.lock().unwrap().clone();
 			let result = match enact_verified(&block, self.engine.deref().deref(), db, &parent, &last_hashes) {
 				Ok(b) => b,
 				Err(e) => {
@@ -302,7 +299,7 @@ impl Client {
 
 	/// Get a copy of the best block's state.
 	pub fn state(&self) -> State {
-		State::from_existing(JournalDB::new_with_arc(self.state_db.clone()), HeaderView::new(&self.best_block_header()).state_root(), self.engine.account_start_nonce())
+		State::from_existing(self.state_db.lock().unwrap().clone(), HeaderView::new(&self.best_block_header()).state_root(), self.engine.account_start_nonce())
 	}
 
 	/// Get info on the cache.

util/src/journaldb.rs

@@ -92,7 +92,6 @@ impl JournalDB {
 
 	/// Commit all recent insert operations and historical removals from the old era
 	/// to the backing database.
-	#[allow(cyclomatic_complexity)]
 	pub fn commit(&mut self, now: u64, id: &H256, end: Option<(u64, H256)>) -> Result<u32, UtilError> {
 		// journal format: 
 		// [era, 0] => [ id, [insert_0, ...], [remove_0, ...] ]
@@ -105,6 +104,17 @@ impl JournalDB {
 		// for each end_era that we journaled that we are no passing by, 
 		// we remove all of its removes assuming it is canonical and all
 		// of its inserts otherwise.
+		//
+		// We also keep reference counters for each key inserted in the journal to handle 
+		// the following cases where key K must not be deleted from the DB when processing removals :
+		// Given H is the journal size in eras, 0 <= C <= H.
+		// Key K is removed in era A(N) and re-inserted in canonical era B(N + C).
+		// Key K is removed in era A(N) and re-inserted in non-canonical era B`(N + C).
+		// Key K is added in non-canonical era A'(N) canonical B(N + C).
+		//
+		// The counter is encreased each time a key is inserted in the journal in the commit. The list of insertions
+		// is saved with the era record. When the era becomes end_era and goes out of journal the counter is decreased
+		// and the key is safe to delete.
 
 		// record new commit's details.
 		let batch = WriteBatch::new();
@@ -125,6 +135,7 @@ impl JournalDB {
 
 			let mut r = RlpStream::new_list(3);
 			let inserts: Vec<H256> = self.overlay.keys().iter().filter(|&(_, &c)| c > 0).map(|(key, _)| key.clone()).collect();
+			// Increase counter for each inserted key no matter if the block is canonical or not. 
 			for i in &inserts {
 				*counters.entry(i.clone()).or_insert(0) += 1;
 			}
@@ -139,6 +150,8 @@ impl JournalDB {
 		if let Some((end_era, canon_id)) = end {
 			let mut index = 0usize;
 			let mut last;
+			let mut to_remove: Vec<H256> = Vec::new();
+			let mut canon_inserts: Vec<H256> = Vec::new();
 			while let Some(rlp_data) = try!(self.backing.get({
 				let mut r = RlpStream::new_list(2);
 				r.append(&end_era);
@@ -146,39 +159,33 @@ impl JournalDB {
 				last = r.drain();
 				&last
 			})) {
-				let to_add;
 				let rlp = Rlp::new(&rlp_data);
-				{
+				let inserts: Vec<H256> = rlp.val_at(1);
-					to_add = rlp.val_at(1);
+				JournalDB::decrease_counters(&inserts, &mut counters);
-					for i in &to_add {
+				// Collect keys to be removed. These are removed keys for canonical block, inserted for non-canonical
-						let delete_counter = {
+				if canon_id == rlp.val_at(0) {
-							if let Some(mut cnt) = counters.get_mut(i) {
+					to_remove.extend(rlp.at(2).iter().map(|r| r.as_val::<H256>()));
-								*cnt -= 1;
+					canon_inserts = inserts;
-								*cnt == 0 
 				}
-							else { false }
+				else {
-								 
+					to_remove.extend(inserts);
-						};
-						if delete_counter { 
-							counters.remove(i); 
 				}
-					}
-				}
-				let to_remove: Vec<H256> = if canon_id == rlp.val_at(0) {rlp.val_at(2)} else {to_add};
-				for i in &to_remove {
-					if !counters.contains_key(i) {
-						batch.delete(&i).expect("Low-level database error. Some issue with your hard disk?");
-					}
-				}
-
 				try!(batch.delete(&last));
-				trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, to_remove.len());
 				index += 1;
 			}
 
+			let canon_inserts = canon_inserts.drain(..).collect::<HashSet<_>>();
+			// Purge removed keys if they are not referenced and not re-inserted in the canon commit
+			let mut deletes = 0;
+			for h in to_remove.iter().filter(|h| !counters.contains_key(h) && !canon_inserts.contains(h)) {
+				try!(batch.delete(&h));
+				deletes += 1;
+			}
 			try!(batch.put(&LAST_ERA_KEY, &encode(&end_era)));
+			trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, deletes);
 		}
 
+		// Commit overlay insertions
 		let mut ret = 0u32;
 		let mut deletes = 0usize;
 		for i in self.overlay.drain().into_iter() {
@@ -200,6 +207,21 @@ impl JournalDB {
 		Ok(ret)
 	}
 
+
+	// Decrease counters for given keys. Deletes obsolete counters
+	fn decrease_counters(keys: &[H256], counters: &mut HashMap<H256, i32>) {
+		for i in keys.iter() {
+			let delete_counter = {
+				let cnt = counters.get_mut(i).expect("Missing key counter");
+				*cnt -= 1;
+				*cnt == 0
+			};
+			if delete_counter {
+				counters.remove(i);
+			}
+		}
+	}
+
 	fn payload(&self, key: &H256) -> Option<Bytes> {
 		self.backing.get(&key.bytes()).expect("Low-level database error. Some issue with your hard disk?").map(|v| v.to_vec())
 	}
@@ -387,4 +409,21 @@ mod tests {
 		jdb.commit(3, &b"2".sha3(), Some((0, b"2".sha3()))).unwrap();
 		assert!(jdb.exists(&foo));
 	}
+
+	#[test]
+	fn fork_same_key() {
+		// history is 1
+		let mut jdb = JournalDB::new_temp();
+		jdb.commit(0, &b"0".sha3(), None).unwrap();
+
+		let foo = jdb.insert(b"foo");
+		jdb.commit(1, &b"1a".sha3(), Some((0, b"0".sha3()))).unwrap();
+
+		jdb.insert(b"foo");
+		jdb.commit(1, &b"1b".sha3(), Some((0, b"0".sha3()))).unwrap();
+		assert!(jdb.exists(&foo));
+
+		jdb.commit(2, &b"2a".sha3(), Some((1, b"1a".sha3()))).unwrap();
+		assert!(jdb.exists(&foo));
+	}
 }