Merge branch 'network' into verification

Cargo.toml

@@ -15,6 +15,7 @@ flate2 = "0.2"
 rocksdb = "0.2.1"
 heapsize = "0.2.0"
 rust-crypto = "0.2.34"
+time = "0.1"
 
 evmjit = { path = "rust-evmjit", optional = true }
 

src/bin/client.rs

@@ -16,10 +16,10 @@ fn main() {
 	::env_logger::init().ok();
 	let mut service = NetworkService::start().unwrap();
 	//TODO: replace with proper genesis and chain params.
-	let frontier = ethereum::new_frontier();
+	let spec = ethereum::new_frontier();
 	let mut dir = env::temp_dir();
 	dir.push(H32::random().hex());
-	let client = Arc::new(Client::new(&frontier.genesis_block(), &dir));
+	let client = Arc::new(Client::new(spec, &dir).unwrap());
 	EthSync::register(&mut service, client);
 	loop {
 		let mut cmd = String::new();

src/block.rs

@@ -21,7 +21,16 @@ pub struct Block {
 	uncles: Vec<Header>,
 }
 
+/// A set of references to `Block` fields that are publicly accessible. 
+pub struct BlockRefMut<'a> {
+	pub header: &'a Header,
+	pub state: &'a mut State,
+	pub archive: &'a Vec<Entry>,
+	pub uncles: &'a Vec<Header>,
+}
+
 impl Block {
+	/// Create a new block from the given `state`.
 	fn new(state: State) -> Block {
 		Block {
 			header: Header::new(),
@@ -32,7 +41,15 @@ impl Block {
 		}
 	}
 
-	pub fn state_mut(&mut self) -> &mut State { &mut self.state }
+	/// Get a structure containing individual references to all public fields.
+	pub fn fields(&mut self) -> BlockRefMut {
+		BlockRefMut {
+			header: &self.header,
+			state: &mut self.state,
+			archive: &self.archive,
+			uncles: &self.uncles,
+		}
+	}
 }
 
 /// Trait for a object that is_a `Block`.
@@ -61,18 +78,18 @@ impl IsBlock for Block {
 ///
 /// It's a bit like a Vec<Transaction>, eccept that whenever a transaction is pushed, we execute it and
 /// maintain the system `state()`. We also archive execution receipts in preparation for later block creation.
-pub struct OpenBlock<'engine> {
+pub struct OpenBlock<'x, 'y> {
 	block: Block,
-	engine: &'engine Engine,
+	engine: &'x Engine,
-	last_hashes: LastHashes,
+	last_hashes: &'y LastHashes,
 }
 
 /// Just like OpenBlock, except that we've applied `Engine::on_close_block`, finished up the non-seal header fields,
 /// and collected the uncles.
 ///
 /// There is no function available to push a transaction. If you want that you'll need to `reopen()` it.
-pub struct ClosedBlock<'engine> {
+pub struct ClosedBlock<'x, 'y> {
-	open_block: OpenBlock<'engine>,
+	open_block: OpenBlock<'x, 'y>,
 	uncle_bytes: Bytes,
 }
 
@@ -84,9 +101,9 @@ pub struct SealedBlock {
 	uncle_bytes: Bytes,
 }
 
-impl<'engine> OpenBlock<'engine> {
+impl<'x, 'y> OpenBlock<'x, 'y> {
 	/// Create a new OpenBlock ready for transaction pushing.
-	pub fn new<'a>(engine: &'a Engine, db: OverlayDB, parent: &Header, last_hashes: LastHashes, author: Address, extra_data: Bytes) -> OpenBlock<'a> {
+	pub fn new<'a, 'b>(engine: &'a Engine, db: OverlayDB, parent: &Header, last_hashes: &'b LastHashes, author: Address, extra_data: Bytes) -> OpenBlock<'a, 'b> {
 		let mut r = OpenBlock {
 			block: Block::new(State::from_existing(db, parent.state_root.clone(), engine.account_start_nonce())),
 			engine: engine,
@@ -95,6 +112,8 @@ impl<'engine> OpenBlock<'engine> {
 
 		r.block.header.set_author(author);
 		r.block.header.set_extra_data(extra_data);
+		r.block.header.set_timestamp_now();
+
 		engine.populate_from_parent(&mut r.block.header, parent);
 		engine.on_new_block(&mut r.block);
 		r
@@ -103,6 +122,9 @@ impl<'engine> OpenBlock<'engine> {
 	/// Alter the author for the block.
 	pub fn set_author(&mut self, author: Address) { self.block.header.set_author(author); }
 
+	/// Alter the timestamp of the block.
+	pub fn set_timestamp(&mut self, timestamp: u64) { self.block.header.set_timestamp(timestamp); }
+
 	/// Alter the extra_data for the block.
 	pub fn set_extra_data(&mut self, extra_data: Bytes) -> Result<(), BlockError> {
 		if extra_data.len() > self.engine.maximum_extra_data_size() {
@@ -131,9 +153,9 @@ impl<'engine> OpenBlock<'engine> {
 	pub fn env_info(&self) -> EnvInfo {
 		// TODO: memoise.
 		EnvInfo {
-			number: self.block.header.number.clone(),
+			number: self.block.header.number,
 			author: self.block.header.author.clone(),
-			timestamp: self.block.header.timestamp.clone(),
+			timestamp: self.block.header.timestamp,
 			difficulty: self.block.header.difficulty.clone(),
 			last_hashes: self.last_hashes.clone(),
 			gas_used: self.block.archive.last().map(|t| t.receipt.gas_used).unwrap_or(U256::from(0)),
@@ -157,7 +179,7 @@ impl<'engine> OpenBlock<'engine> {
 	}
 
 	/// Turn this into a `ClosedBlock`. A BlockChain must be provided in order to figure out the uncles.
-	pub fn close(self) -> ClosedBlock<'engine> {
+	pub fn close(self) -> ClosedBlock<'x, 'y> {
 		let mut s = self;
 		s.engine.on_close_block(&mut s.block);
 		s.block.header.transactions_root = ordered_trie_root(s.block.archive.iter().map(|ref e| e.transaction.rlp_bytes()).collect());
@@ -173,16 +195,16 @@ impl<'engine> OpenBlock<'engine> {
 	}
 }
 
-impl<'engine> IsBlock for OpenBlock<'engine> {
+impl<'x, 'y> IsBlock for OpenBlock<'x, 'y> {
 	fn block(&self) -> &Block { &self.block }
 }
 
-impl<'engine> IsBlock for ClosedBlock<'engine> {
+impl<'x, 'y> IsBlock for ClosedBlock<'x, 'y> {
 	fn block(&self) -> &Block { &self.open_block.block }
 }
 
-impl<'engine> ClosedBlock<'engine> {
+impl<'x, 'y> ClosedBlock<'x, 'y> {
-	fn new<'a>(open_block: OpenBlock<'a>, uncle_bytes: Bytes) -> ClosedBlock<'a> {
+	fn new<'a, 'b>(open_block: OpenBlock<'a, 'b>, uncle_bytes: Bytes) -> ClosedBlock<'a, 'b> {
 		ClosedBlock {
 			open_block: open_block,
 			uncle_bytes: uncle_bytes,
@@ -205,7 +227,7 @@ impl<'engine> ClosedBlock<'engine> {
 	}
 
 	/// Turn this back into an `OpenBlock`.
-	pub fn reopen(self) -> OpenBlock<'engine> { self.open_block }
+	pub fn reopen(self) -> OpenBlock<'x, 'y> { self.open_block }
 }
 
 impl SealedBlock {
@@ -218,12 +240,25 @@ impl SealedBlock {
 		block_rlp.append_raw(&self.uncle_bytes, 1);
 		block_rlp.out()
 	}
+
+	/// Drop this object and return the underlieing database.
+	pub fn drain(self) -> OverlayDB { self.block.state.drop().1 }
 }
 
 impl IsBlock for SealedBlock {
 	fn block(&self) -> &Block { &self.block }
 }
 
+pub fn enact(rlp_bytes: &[u8], engine: &Engine, db: OverlayDB, parent: &Header, last_hashes: &LastHashes) -> Result<SealedBlock, Error> {
+	let block = BlockView::new(rlp_bytes);
+	let header = block.header_view();
+	let mut b = OpenBlock::new(engine, db, parent, last_hashes, header.author(), header.extra_data());
+	b.set_timestamp(header.timestamp());
+	for t in block.transactions().into_iter() { try!(b.push_transaction(t, None)); }
+	for u in block.uncles().into_iter() { try!(b.push_uncle(u)); }
+	Ok(try!(b.close().seal(header.seal())))
+}
+
 #[test]
 fn open_block() {
 	use spec::*;
@@ -231,7 +266,30 @@ fn open_block() {
 	let genesis_header = engine.spec().genesis_header();
 	let mut db = OverlayDB::new_temp();
 	engine.spec().ensure_db_good(&mut db);
-	let b = OpenBlock::new(engine.deref(), db, &genesis_header, vec![genesis_header.hash()], Address::zero(), vec![]);
+	let last_hashes = vec![genesis_header.hash()];
+	let b = OpenBlock::new(engine.deref(), db, &genesis_header, &last_hashes, Address::zero(), vec![]);
 	let b = b.close();
 	let _ = b.seal(vec![]);
 }
+
+#[test]
+fn enact_block() {
+	use spec::*;
+	let engine = Spec::new_test().to_engine().unwrap();
+	let genesis_header = engine.spec().genesis_header();
+
+	let mut db = OverlayDB::new_temp();
+	engine.spec().ensure_db_good(&mut db);
+	let b = OpenBlock::new(engine.deref(), db, &genesis_header, &vec![genesis_header.hash()], Address::zero(), vec![]).close().seal(vec![]).unwrap();
+	let orig_bytes = b.rlp_bytes();
+	let orig_db = b.drain();
+
+	let mut db = OverlayDB::new_temp();
+	engine.spec().ensure_db_good(&mut db);
+	let e = enact(&orig_bytes, engine.deref(), db, &genesis_header, &vec![genesis_header.hash()]).unwrap();
+
+	assert_eq!(e.rlp_bytes(), orig_bytes);
+	
+	let db = e.drain();
+	assert_eq!(orig_db.keys(), db.keys());
+}

src/blockchain.rs

@@ -1,6 +1,5 @@
 //! Fast access to blockchain data.
 
-use std::sync::*;
 use util::*;
 use rocksdb::{DB, WriteBatch, Writable};
 use header::*;
@@ -34,7 +33,7 @@ pub struct CacheSize {
 /// Information about best block gathered together
 struct BestBlock {
 	pub hash: H256,
-	pub number: U256,
+	pub number: BlockNumber,
 	pub total_difficulty: U256
 }
 
@@ -42,7 +41,7 @@ impl BestBlock {
 	fn new() -> BestBlock {
 		BestBlock {
 			hash: H256::new(),
-			number: U256::from(0),
+			number: 0,
 			total_difficulty: U256::from(0)
 		}
 	}
@@ -59,7 +58,7 @@ pub struct BlockChain {
 
 	// extra caches
 	block_details: RwLock<HashMap<H256, BlockDetails>>,
-	block_hashes: RwLock<HashMap<U256, H256>>,
+	block_hashes: RwLock<HashMap<BlockNumber, H256>>,
 	transaction_addresses: RwLock<HashMap<H256, TransactionAddress>>,
 	block_logs: RwLock<HashMap<H256, BlockLogBlooms>>,
 	blocks_blooms: RwLock<HashMap<H256, BlocksBlooms>>,
@@ -93,7 +92,7 @@ impl BlockChain {
 	/// 	let genesis_hash = "d4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3";
 	/// 	assert_eq!(bc.genesis_hash(), H256::from_str(genesis_hash).unwrap());
 	/// 	assert!(bc.is_known(&bc.genesis_hash()));
-	/// 	assert_eq!(bc.genesis_hash(), bc.block_hash(&U256::from(0u8)).unwrap());
+	/// 	assert_eq!(bc.genesis_hash(), bc.block_hash(0).unwrap());
 	/// }
 	/// ```
 	pub fn new(genesis: &[u8], path: &Path) -> BlockChain {
@@ -200,11 +199,16 @@ impl BlockChain {
 	///   ```json
 	///   { blocks: [B4, B3, A3, A4], ancestor: A2, index: 2 }
 	///   ```
-	pub fn tree_route(&self, from: H256, to: H256) -> TreeRoute {
+	pub fn tree_route(&self, from: H256, to: H256) -> Option<TreeRoute> {
-		let from_details = self.block_details(&from).expect("from hash is invalid!");
+		let from_details = match self.block_details(&from) {
-		let to_details = self.block_details(&to).expect("to hash is invalid!");
+			Some(h) => h,
-
+			None => return None,
-		self._tree_route((from_details, from), (to_details, to))
+		};
+		let to_details = match self.block_details(&to) {
+			Some(h) => h,
+			None => return None,
+		};
+		Some(self._tree_route((from_details, from), (to_details, to)))
 	}
 
 	/// Similar to `tree_route` function, but can be used to return a route
@@ -337,9 +341,9 @@ impl BlockChain {
 			// it is a fork
 			i if i > 1 => {
 				let ancestor_number = self.block_number(&route.ancestor).unwrap();
-				let start_number = ancestor_number + U256::from(1u8);
+				let start_number = ancestor_number + 1;
 				for (index, hash) in route.blocks.iter().skip(route.index).enumerate() {
-					batch.put_extras(&(start_number + U256::from(index as u64)), hash);
+					batch.put_extras(&(start_number + index as BlockNumber), hash);
 				}
 			},
 			// route.blocks.len() could be 0 only if inserted block is best block,
@@ -372,7 +376,7 @@ impl BlockChain {
 
 	/// Returns reference to genesis hash.
 	pub fn genesis_hash(&self) -> H256 {
-		self.block_hash(&U256::from(0u8)).expect("Genesis hash should always exist")
+		self.block_hash(0).expect("Genesis hash should always exist")
 	}
 
 	/// Get the partial-header of a block.
@@ -410,8 +414,8 @@ impl BlockChain {
 	}
 
 	/// Get the hash of given block's number.
-	pub fn block_hash(&self, hash: &U256) -> Option<H256> {
+	pub fn block_hash(&self, index: BlockNumber) -> Option<H256> {
-		self.query_extras(hash, &self.block_hashes)
+		self.query_extras(&index, &self.block_hashes)
 	}
 
 	/// Get best block hash.
@@ -420,7 +424,7 @@ impl BlockChain {
 	}
 
 	/// Get best block number.
-	pub fn best_block_number(&self) -> U256 {
+	pub fn best_block_number(&self) -> BlockNumber {
 		self.best_block.read().unwrap().number
 	}
 
@@ -430,7 +434,7 @@ impl BlockChain {
 	}
 
 	/// Get the number of given block's hash.
-	pub fn block_number(&self, hash: &H256) -> Option<U256> {
+	pub fn block_number(&self, hash: &H256) -> Option<BlockNumber> {
 		self.block(hash).map(|bytes| BlockView::new(&bytes).header_view().number())
 	}
 
@@ -522,7 +526,6 @@ mod tests {
 	use std::str::FromStr;
 	use rustc_serialize::hex::FromHex;
 	use util::hash::*;
-	use util::uint::*;
 	use blockchain::*;
 
 	#[test]
@@ -537,11 +540,10 @@ mod tests {
 		let genesis_hash = H256::from_str("3caa2203f3d7c136c0295ed128a7d31cea520b1ca5e27afe17d0853331798942").unwrap();
 
 		assert_eq!(bc.genesis_hash(), genesis_hash.clone());
-		assert_eq!(bc.best_block_number(), U256::from(0u8));
+		assert_eq!(bc.best_block_number(), 0);
 		assert_eq!(bc.best_block_hash(), genesis_hash.clone());
-		assert_eq!(bc.block_hash(&U256::from(0u8)), Some(genesis_hash.clone()));
+		assert_eq!(bc.block_hash(0), Some(genesis_hash.clone()));
-		assert_eq!(bc.block_hash(&U256::from(1u8)), None);
+		assert_eq!(bc.block_hash(1), None);
-
 		
 		let first = "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".from_hex().unwrap();
 
@@ -549,13 +551,13 @@ mod tests {
 
 		let first_hash = H256::from_str("a940e5af7d146b3b917c953a82e1966b906dace3a4e355b5b0a4560190357ea1").unwrap();
 
-		assert_eq!(bc.block_hash(&U256::from(0u8)), Some(genesis_hash.clone()));
+		assert_eq!(bc.block_hash(0), Some(genesis_hash.clone()));
-		assert_eq!(bc.best_block_number(), U256::from(1u8));
+		assert_eq!(bc.best_block_number(), 1);
 		assert_eq!(bc.best_block_hash(), first_hash.clone());
-		assert_eq!(bc.block_hash(&U256::from(1u8)), Some(first_hash.clone()));
+		assert_eq!(bc.block_hash(1), Some(first_hash.clone()));
 		assert_eq!(bc.block_details(&first_hash).unwrap().parent, genesis_hash.clone());
 		assert_eq!(bc.block_details(&genesis_hash).unwrap().children, vec![first_hash.clone()]);
-		assert_eq!(bc.block_hash(&U256::from(2u8)), None);
+		assert_eq!(bc.block_hash(2), None);
 	}
 
 	#[test]
@@ -585,64 +587,64 @@ mod tests {
 		bc.insert_block(&b3b);
 
 		assert_eq!(bc.best_block_hash(), best_block_hash);
-		assert_eq!(bc.block_number(&genesis_hash).unwrap(), U256::from(0));
+		assert_eq!(bc.block_number(&genesis_hash).unwrap(), 0);
-		assert_eq!(bc.block_number(&b1_hash).unwrap(), U256::from(1));
+		assert_eq!(bc.block_number(&b1_hash).unwrap(), 1);
-		assert_eq!(bc.block_number(&b2_hash).unwrap(), U256::from(2));
+		assert_eq!(bc.block_number(&b2_hash).unwrap(), 2);
-		assert_eq!(bc.block_number(&b3a_hash).unwrap(), U256::from(3));
+		assert_eq!(bc.block_number(&b3a_hash).unwrap(), 3);
-		assert_eq!(bc.block_number(&b3b_hash).unwrap(), U256::from(3));
+		assert_eq!(bc.block_number(&b3b_hash).unwrap(), 3);
 
-		assert_eq!(bc.block_hash(&U256::from(0)).unwrap(), genesis_hash);
+		assert_eq!(bc.block_hash(0).unwrap(), genesis_hash);
-		assert_eq!(bc.block_hash(&U256::from(1)).unwrap(), b1_hash);
+		assert_eq!(bc.block_hash(1).unwrap(), b1_hash);
-		assert_eq!(bc.block_hash(&U256::from(2)).unwrap(), b2_hash);
+		assert_eq!(bc.block_hash(2).unwrap(), b2_hash);
-		assert_eq!(bc.block_hash(&U256::from(3)).unwrap(), b3a_hash);
+		assert_eq!(bc.block_hash(3).unwrap(), b3a_hash);
 
 		// test trie route
-		let r0_1 = bc.tree_route(genesis_hash.clone(), b1_hash.clone());
+		let r0_1 = bc.tree_route(genesis_hash.clone(), b1_hash.clone()).unwrap();
 		assert_eq!(r0_1.ancestor, genesis_hash);
 		assert_eq!(r0_1.blocks, [b1_hash.clone()]);
 		assert_eq!(r0_1.index, 0);
 
-		let r0_2 = bc.tree_route(genesis_hash.clone(), b2_hash.clone());
+		let r0_2 = bc.tree_route(genesis_hash.clone(), b2_hash.clone()).unwrap();
 		assert_eq!(r0_2.ancestor, genesis_hash);
 		assert_eq!(r0_2.blocks, [b1_hash.clone(), b2_hash.clone()]);
 		assert_eq!(r0_2.index, 0);
 
-		let r1_3a = bc.tree_route(b1_hash.clone(), b3a_hash.clone());
+		let r1_3a = bc.tree_route(b1_hash.clone(), b3a_hash.clone()).unwrap();
 		assert_eq!(r1_3a.ancestor, b1_hash);
 		assert_eq!(r1_3a.blocks, [b2_hash.clone(), b3a_hash.clone()]);
 		assert_eq!(r1_3a.index, 0);
 
-		let r1_3b = bc.tree_route(b1_hash.clone(), b3b_hash.clone());
+		let r1_3b = bc.tree_route(b1_hash.clone(), b3b_hash.clone()).unwrap();
 		assert_eq!(r1_3b.ancestor, b1_hash);
 		assert_eq!(r1_3b.blocks, [b2_hash.clone(), b3b_hash.clone()]);
 		assert_eq!(r1_3b.index, 0);
 
-		let r3a_3b = bc.tree_route(b3a_hash.clone(), b3b_hash.clone());
+		let r3a_3b = bc.tree_route(b3a_hash.clone(), b3b_hash.clone()).unwrap();
 		assert_eq!(r3a_3b.ancestor, b2_hash);
 		assert_eq!(r3a_3b.blocks, [b3a_hash.clone(), b3b_hash.clone()]);
 		assert_eq!(r3a_3b.index, 1);
 
-		let r1_0 = bc.tree_route(b1_hash.clone(), genesis_hash.clone());
+		let r1_0 = bc.tree_route(b1_hash.clone(), genesis_hash.clone()).unwrap();
 		assert_eq!(r1_0.ancestor, genesis_hash);
 		assert_eq!(r1_0.blocks, [b1_hash.clone()]);
 		assert_eq!(r1_0.index, 1);
 
-		let r2_0 = bc.tree_route(b2_hash.clone(), genesis_hash.clone());
+		let r2_0 = bc.tree_route(b2_hash.clone(), genesis_hash.clone()).unwrap();
 		assert_eq!(r2_0.ancestor, genesis_hash);
 		assert_eq!(r2_0.blocks, [b2_hash.clone(), b1_hash.clone()]);
 		assert_eq!(r2_0.index, 2);
 
-		let r3a_1 = bc.tree_route(b3a_hash.clone(), b1_hash.clone());
+		let r3a_1 = bc.tree_route(b3a_hash.clone(), b1_hash.clone()).unwrap();
 		assert_eq!(r3a_1.ancestor, b1_hash);
 		assert_eq!(r3a_1.blocks, [b3a_hash.clone(), b2_hash.clone()]);
 		assert_eq!(r3a_1.index, 2);
 
-		let r3b_1 = bc.tree_route(b3b_hash.clone(), b1_hash.clone());
+		let r3b_1 = bc.tree_route(b3b_hash.clone(), b1_hash.clone()).unwrap();
 		assert_eq!(r3b_1.ancestor, b1_hash);
 		assert_eq!(r3b_1.blocks, [b3b_hash.clone(), b2_hash.clone()]);
 		assert_eq!(r3b_1.index, 2);
 
-		let r3b_3a = bc.tree_route(b3b_hash.clone(), b3a_hash.clone());
+		let r3b_3a = bc.tree_route(b3b_hash.clone(), b3a_hash.clone()).unwrap();
 		assert_eq!(r3b_3a.ancestor, b2_hash);
 		assert_eq!(r3b_3a.blocks, [b3b_hash.clone(), b3a_hash.clone()]);
 		assert_eq!(r3b_3a.index, 1);

src/builtin.rs

@@ -12,6 +12,11 @@ pub struct Builtin {
 	pub execute: Box<Fn(&[u8], &mut [u8])>,
 }
 
+// Rust does not mark closurer that do not capture as Sync
+// We promise that all builtins are thread safe since they only operate on given input.
+unsafe impl Sync for Builtin {}
+unsafe impl Send for Builtin {}
+
 impl fmt::Debug for Builtin {
 	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 		write!(f, "<Builtin>")

src/client.rs

@@ -1,22 +1,17 @@
-use std::sync::Arc;
 use util::*;
 use blockchain::BlockChain;
 use views::BlockView;
-
+use error::*;
-/// Status for a block in a queue.
+use header::BlockNumber;
-pub enum QueueStatus {
+use spec::Spec;
-	/// Part of the known chain.
+use engine::Engine;
-	Known,
-	/// Part of the unknown chain.
-	Unknown,
-}
 
 /// General block status
 pub enum BlockStatus {
 	/// Part of the blockchain.
 	InChain,
 	/// Queued for import.
-	Queued(QueueStatus),
+	Queued,
 	/// Known as bad.
 	Bad,
 	/// Unknown.
@@ -24,16 +19,7 @@ pub enum BlockStatus {
 }
 
 /// Result of import block operation.
-pub enum ImportResult {
+pub type ImportResult = Result<(), ImportError>;
-	/// Added to import queue.
-	Queued(QueueStatus),
-	/// Already in the chain.
-	AlreadyInChain,
-	/// Already queued for import.
-	AlreadyQueued(QueueStatus),
-	/// Bad or already known as bad.
-	Bad,
-}
 
 /// Information about the blockchain gthered together.
 pub struct BlockChainInfo {
@@ -56,8 +42,6 @@ pub struct BlockQueueStatus {
 
 pub type TreeRoute = ::blockchain::TreeRoute;
 
-pub type BlockNumber = u64;
-
 /// Blockchain database client. Owns and manages a blockchain and a block queue.
 pub trait BlockChainClient : Sync {
 	/// Get raw block header data by block header hash.
@@ -88,7 +72,7 @@ pub trait BlockChainClient : Sync {
 
 	/// Get a tree route between `from` and `to`.
 	/// See `BlockChain::tree_route`.
-	fn tree_route(&self, from: &H256, to: &H256) -> TreeRoute;
+	fn tree_route(&self, from: &H256, to: &H256) -> Option<TreeRoute>;
 
 	/// Get latest state node
 	fn state_data(&self, hash: &H256) -> Option<Bytes>;
@@ -112,14 +96,17 @@ pub trait BlockChainClient : Sync {
 /// Blockchain database client backed by a persistent database. Owns and manages a blockchain and a block queue.
 pub struct Client {
 	chain: Arc<BlockChain>,
+	_engine: Arc<Box<Engine>>,
 }
 
 impl Client {
-	pub fn new(genesis: &[u8], path: &Path) -> Client {
+	pub fn new(spec: Spec, path: &Path) -> Result<Client, Error> {
-		let chain = Arc::new(BlockChain::new(genesis, path));
+		let chain = Arc::new(BlockChain::new(&spec.genesis_block(), path));
-		Client {
+		let engine = Arc::new(try!(spec.to_engine()));
+		Ok(Client {
 			chain: chain.clone(),
-		}
+			_engine: engine,
+		})
 	}
 }
 
@@ -147,25 +134,25 @@ impl BlockChainClient for Client {
 	}
 
 	fn block_header_at(&self, n: BlockNumber) -> Option<Bytes> {
-		self.chain.block_hash(&From::from(n)).and_then(|h| self.block_header(&h))
+		self.chain.block_hash(n).and_then(|h| self.block_header(&h))
 	}
 
 	fn block_body_at(&self, n: BlockNumber) -> Option<Bytes> {
-		self.chain.block_hash(&From::from(n)).and_then(|h| self.block_body(&h))
+		self.chain.block_hash(n).and_then(|h| self.block_body(&h))
 	}
 
 	fn block_at(&self, n: BlockNumber) -> Option<Bytes> {
-		self.chain.block_hash(&From::from(n)).and_then(|h| self.block(&h))
+		self.chain.block_hash(n).and_then(|h| self.block(&h))
 	}
 
 	fn block_status_at(&self, n: BlockNumber) -> BlockStatus {
-		match self.chain.block_hash(&From::from(n)) {
+		match self.chain.block_hash(n) {
 			Some(h) => self.block_status(&h),
 			None => BlockStatus::Unknown
 		}
 	}
 
-	fn tree_route(&self, from: &H256, to: &H256) -> TreeRoute {
+	fn tree_route(&self, from: &H256, to: &H256) -> Option<TreeRoute> {
 		self.chain.tree_route(from.clone(), to.clone())
 	}
 
@@ -184,11 +171,11 @@ impl BlockChainClient for Client {
 			let header = block.header_view();
 			let hash = header.sha3();
 			if self.chain.is_known(&hash) {
-				return ImportResult::Bad;
+				return Err(ImportError::AlreadyInChain);
 			}
 		}
 		self.chain.insert_block(bytes);
-		ImportResult::Queued(QueueStatus::Known)
+		Ok(())
 	}
 
 	fn queue_status(&self) -> BlockQueueStatus {

src/engine.rs

@@ -4,7 +4,7 @@ use spec::Spec;
 
 /// A consensus mechanism for the chain. Generally either proof-of-work or proof-of-stake-based.
 /// Provides hooks into each of the major parts of block import.
-pub trait Engine {
+pub trait Engine : Sync + Send {
 	/// The name of this engine.
 	fn name(&self) -> &str;
 	/// The version of this engine. Should be of the form 

src/env_info.rs

@@ -1,4 +1,5 @@
 use util::*;
+use header::BlockNumber;
 
 /// Simple vector of hashes, should be at most 256 items large, can be smaller if being used
 /// for a block whose number is less than 257.
@@ -7,11 +8,11 @@ pub type LastHashes = Vec<H256>;
 /// Information concerning the execution environment for a message-call/contract-creation.
 pub struct EnvInfo {
 	/// The block number.
-	pub number: U256,
+	pub number: BlockNumber,
 	/// The block author.
 	pub author: Address,
 	/// The block timestamp.
-	pub timestamp: U256,
+	pub timestamp: u64,
 	/// The block difficulty.
 	pub difficulty: U256,
 	/// The block gas limit.

src/error.rs

@@ -1,6 +1,7 @@
 //! General error types for use in ethcore.
 
 use util::*;
+use header::BlockNumber;
 
 #[derive(Debug)]
 pub struct Mismatch<T: fmt::Debug> {
@@ -23,8 +24,8 @@ pub enum BlockError {
 	InvalidSealArity(Mismatch<usize>),
 	TooMuchGasUsed(OutOfBounds<U256>),
 	InvalidUnclesHash(Mismatch<H256>),
-	UncleTooOld(OutOfBounds<U256>),
+	UncleTooOld(OutOfBounds<BlockNumber>),
-	UncleIsBrother(OutOfBounds<U256>),
+	UncleIsBrother(OutOfBounds<BlockNumber>),
 	UncleInChain(H256),
 	UncleParentNotInChain(H256),
 	InvalidStateRoot,
@@ -33,15 +34,22 @@ pub enum BlockError {
 	InvalidDifficulty(Mismatch<U256>),
 	InvalidGasLimit(OutOfBounds<U256>),
 	InvalidReceiptsStateRoot,
-	InvalidTimestamp(OutOfBounds<U256>),
+	InvalidTimestamp(OutOfBounds<u64>),
 	InvalidLogBloom,
 	InvalidBlockNonce,
 	InvalidParentHash(Mismatch<H256>),
-	InvalidNumber(OutOfBounds<U256>),
+	InvalidNumber(OutOfBounds<BlockNumber>),
 	UnknownParent(H256),
 	UnknownUncleParent(H256),
 }
 
+#[derive(Debug)]
+pub enum ImportError {
+	Bad(BlockError),
+	AlreadyInChain,
+	AlreadyQueued,
+}
+
 #[derive(Debug)]
 /// General error type which should be capable of representing all errors in ethcore.
 pub enum Error {

src/ethereum/ethash.rs

@@ -17,13 +17,31 @@ impl Ethash {
 
 impl Engine for Ethash {
 	fn name(&self) -> &str { "Ethash" }
+	fn version(&self) -> SemanticVersion { SemanticVersion::new(1, 0, 0) }
+	// Two fields - mix
+	fn seal_fields(&self) -> usize { 2 }
+	// Two empty data items in RLP.
+	fn seal_rlp(&self) -> Bytes { encode(&H64::new()) }
+
+	/// Additional engine-specific information for the user/developer concerning `header`.
+	fn extra_info(&self, _header: &Header) -> HashMap<String, String> { HashMap::new() }
 	fn spec(&self) -> &Spec { &self.spec }
 	fn evm_schedule(&self, _env_info: &EnvInfo) -> EvmSchedule { EvmSchedule::new_frontier() }
 
 	/// Apply the block reward on finalisation of the block.
+	/// This assumes that all uncles are valid uncles (i.e. of at least one generation before the current).
 	fn on_close_block(&self, block: &mut Block) {
-		let a = block.header().author.clone();
+		let reward = self.spec().engine_params.get("blockReward").map(|a| decode(&a)).unwrap_or(U256::from(0u64));
-		block.state_mut().add_balance(&a, &decode(&self.spec().engine_params.get("blockReward").unwrap()));
+		let fields = block.fields();
+
+		// Bestow block reward
+		fields.state.add_balance(&fields.header.author, &(reward + reward / U256::from(32) * U256::from(fields.uncles.len())));
+
+		// Bestow uncle rewards
+		let current_number = fields.header.number();
+		for u in fields.uncles.iter() {
+			fields.state.add_balance(u.author(), &(reward * U256::from((8 + u.number() - current_number) / 8)));
+		}
 	}
 
 
@@ -37,7 +55,7 @@ impl Engine for Ethash {
 			return Err(From::from(BlockError::InvalidGasLimit(OutOfBounds { min: min_gas_limit, max: From::from(0), found: header.gas_limit }))); 
 		}
 		let maximum_extra_data_size = self.maximum_extra_data_size();
-		if header.number != From::from(0) && header.extra_data.len() > maximum_extra_data_size {
+		if header.number != 0 && header.extra_data.len() > maximum_extra_data_size {
 			return Err(From::from(BlockError::ExtraDataOutOfBounds(OutOfBounds { min: 0, max: maximum_extra_data_size, found: header.extra_data.len() }))); 
 		}
 		// TODO: Verify seal (quick)
@@ -70,13 +88,13 @@ impl Engine for Ethash {
 impl Ethash {
 	fn calculate_difficuty(&self, header: &Header, parent: &Header) -> U256 {
 		const EXP_DIFF_PERIOD: u64 = 100000;
-		if header.number == From::from(0) {
+		if header.number == 0 {
 			panic!("Can't calculate genesis block difficulty");
 		}
 
 		let min_difficulty = decode(self.spec().engine_params.get("minimumDifficulty").unwrap());
 		let difficulty_bound_divisor = decode(self.spec().engine_params.get("difficultyBoundDivisor").unwrap());
-		let duration_limit = decode(self.spec().engine_params.get("durationLimit").unwrap());
+		let duration_limit: u64 = decode(self.spec().engine_params.get("durationLimit").unwrap());
 		let frontier_limit = decode(self.spec().engine_params.get("frontierCompatibilityModeLimit").unwrap());
 		let mut target = if header.number < frontier_limit {
 			if header.timestamp >= parent.timestamp + duration_limit {
@@ -87,16 +105,16 @@ impl Ethash {
 			}
 		}
 		else {
-			let diff_inc = (header.timestamp - parent.timestamp) / From::from(10);
+			let diff_inc = (header.timestamp - parent.timestamp) / 10;
-			if diff_inc <= From::from(1) {
+			if diff_inc <= 1 {
-				parent.difficulty + parent.difficulty / From::from(2048) * (U256::from(1) - diff_inc)
+				parent.difficulty + parent.difficulty / From::from(2048) * From::from(1 - diff_inc)
 			}
 			else {
-				parent.difficulty - parent.difficulty / From::from(2048) * max(diff_inc - From::from(1), From::from(99))
+				parent.difficulty - parent.difficulty / From::from(2048) * From::from(max(diff_inc - 1, 99))
 			}
 		};
 		target = max(min_difficulty, target);
-		let period = ((parent.number + From::from(1)).as_u64() / EXP_DIFF_PERIOD) as usize;
+		let period = ((parent.number + 1) / EXP_DIFF_PERIOD) as usize;
 		if period > 1 {
 			target = max(min_difficulty, target + (U256::from(1) << (period - 2)));
 		}
@@ -111,9 +129,10 @@ fn on_close_block() {
 	let genesis_header = engine.spec().genesis_header();
 	let mut db = OverlayDB::new_temp();
 	engine.spec().ensure_db_good(&mut db);
-	let b = OpenBlock::new(engine.deref(), db, &genesis_header, vec![genesis_header.hash()], Address::zero(), vec![]);
+	let last_hashes = vec![genesis_header.hash()];
+	let b = OpenBlock::new(engine.deref(), db, &genesis_header, &last_hashes, Address::zero(), vec![]);
 	let b = b.close();
-	assert_eq!(b.state().balance(&Address::zero()), U256::from_str("4563918244F40000").unwrap());
+	assert_eq!(b.state().balance(&Address::zero()), U256::from_str("4563918244f40000").unwrap());
 }
 
 // TODO: difficulty test

src/ethereum/mod.rs

@@ -52,7 +52,7 @@ mod tests {
 	fn morden() {
 		let morden = new_morden();
 
-		assert_eq!(*morden.state_root(), H256::from_str("f3f4696bbf3b3b07775128eb7a3763279a394e382130f27c21e70233e04946a9").unwrap());
+		assert_eq!(morden.state_root(), H256::from_str("f3f4696bbf3b3b07775128eb7a3763279a394e382130f27c21e70233e04946a9").unwrap());
 		let genesis = morden.genesis_block();
 		assert_eq!(BlockView::new(&genesis).header_view().sha3(), H256::from_str("0cd786a2425d16f152c658316c423e6ce1181e15c3295826d7c9904cba9ce303").unwrap());
 
@@ -63,7 +63,7 @@ mod tests {
 	fn frontier() {
 		let frontier = new_frontier();
 
-		assert_eq!(*frontier.state_root(), H256::from_str("d7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544").unwrap());
+		assert_eq!(frontier.state_root(), H256::from_str("d7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544").unwrap());
 		let genesis = frontier.genesis_block();
 		assert_eq!(BlockView::new(&genesis).header_view().sha3(), H256::from_str("d4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3").unwrap());
 

src/extras.rs

@@ -1,4 +1,5 @@
 use util::*;
+use header::BlockNumber;
 use rocksdb::{DB, Writable};
 
 /// Represents index of extra data in database
@@ -74,6 +75,13 @@ impl ExtrasSliceConvertable for U256 {
 	}
 }
 
+// NICE: make less horrible.
+impl ExtrasSliceConvertable for BlockNumber {
+	fn to_extras_slice(&self, i: ExtrasIndex) -> H264 {
+		U256::from(*self).to_extras_slice(i)
+	}
+}
+
 /// Types implementing this trait can be indexed in extras database
 pub trait ExtrasIndexable {
 	fn extras_index() -> ExtrasIndex;
@@ -88,7 +96,7 @@ impl ExtrasIndexable for H256 {
 /// Familial details concerning a block
 #[derive(Debug, Clone)]
 pub struct BlockDetails {
-	pub number: U256,
+	pub number: BlockNumber,
 	pub total_difficulty: U256,
 	pub parent: H256,
 	pub children: Vec<H256>

src/header.rs

@@ -1,5 +1,8 @@
 use util::*;
 use basic_types::*;
+use time::now_utc;
+
+pub type BlockNumber = u64;
 
 /// A block header.
 ///
@@ -11,8 +14,8 @@ use basic_types::*;
 pub struct Header {
 	// TODO: make all private.
 	pub parent_hash: H256,
-	pub timestamp: U256,
+	pub timestamp: u64,
-	pub number: U256,
+	pub number: BlockNumber,
 	pub author: Address,
 
 	pub transactions_root: H256,
@@ -41,8 +44,8 @@ impl Header {
 	pub fn new() -> Header {
 		Header {
 			parent_hash: ZERO_H256.clone(),
-			timestamp: BAD_U256,
+			timestamp: 0,
-			number: ZERO_U256,
+			number: 0,
 			author: ZERO_ADDRESS.clone(),
 
 			transactions_root: SHA3_NULL_RLP,
@@ -61,14 +64,23 @@ impl Header {
 		}
 	}
 
+	pub fn number(&self) -> BlockNumber { self.number }
+	pub fn timestamp(&self) -> u64 { self.timestamp }
 	pub fn author(&self) -> &Address { &self.author }
+
 	pub fn extra_data(&self) -> &Bytes { &self.extra_data }
+
 	pub fn seal(&self) -> &Vec<Bytes> { &self.seal }
 
 	// TODO: seal_at, set_seal_at &c.
 
+	pub fn set_number(&mut self, a: BlockNumber) { self.number = a; self.note_dirty(); }
+	pub fn set_timestamp(&mut self, a: u64) { self.timestamp = a; self.note_dirty(); }
+	pub fn set_timestamp_now(&mut self) { self.timestamp = now_utc().to_timespec().sec as u64; self.note_dirty(); }
 	pub fn set_author(&mut self, a: Address) { if a != self.author { self.author = a; self.note_dirty(); } }
+
 	pub fn set_extra_data(&mut self, a: Bytes) { if a != self.extra_data { self.extra_data = a; self.note_dirty(); } }
+
 	pub fn set_seal(&mut self, a: Vec<Bytes>) { self.seal = a; self.note_dirty(); }
 
 	/// Get the hash of this header (sha3 of the RLP).

src/lib.rs

@@ -78,6 +78,7 @@ extern crate flate2;
 extern crate rocksdb;
 extern crate heapsize;
 extern crate crypto;
+extern crate time;
 
 extern crate env_logger;
 #[cfg(feature = "jit" )]

src/queue.rs

@@ -1,26 +1,24 @@
 use std::sync::Arc;
-//use util::bytes::*;
+use util::*;
-use util::sha3::*;
 use blockchain::BlockChain;
 use client::{QueueStatus, ImportResult};
 use views::{BlockView};
 
-
+/// A queue of blocks. Sits between network or other I/O and the BlockChain.
-pub struct BlockQueue {
+/// Sorts them ready for blockchain insertion.
-	chain: Arc<BlockChain>
+pub struct BlockQueue;
-}
 
 impl BlockQueue {
-	pub fn new(chain: Arc<BlockChain>) -> BlockQueue {
+	/// Creates a new queue instance.
-		BlockQueue {
+	pub fn new() -> BlockQueue {
-			chain: chain
-		}
 	}
 
+	/// Clear the queue and stop verification activity.
 	pub fn clear(&mut self) {
 	}
 
-	pub fn import_block(&mut self, bytes: &[u8]) -> ImportResult {
+	/// Add a block to the queue.
+	pub fn import_block(&mut self, bytes: &[u8], bc: &mut BlockChain) -> ImportResult {
 		//TODO: verify block
 		{
 			let block = BlockView::new(bytes);
@@ -30,7 +28,7 @@ impl BlockQueue {
 				return ImportResult::Bad;
 			}
 		}
-		self.chain.insert_block(bytes);
+		bc.insert_block(bytes);
 		ImportResult::Queued(QueueStatus::Known)
 	}
 }

src/spec.rs

@@ -40,6 +40,27 @@ fn json_to_rlp_map(json: &Json) -> HashMap<String, Bytes> {
 	})
 }
 
+//TODO: add code and data
+#[derive(Debug)]
+/// Genesis account data. Does no thave a DB overlay cache
+pub struct GenesisAccount {
+	// Balance of the account.
+	balance: U256,
+	// Nonce of the account.
+	nonce: U256,
+}
+
+impl GenesisAccount {
+	pub fn rlp(&self) -> Bytes {
+		let mut stream = RlpStream::new_list(4);
+		stream.append(&self.nonce);
+		stream.append(&self.balance);
+		stream.append(&SHA3_NULL_RLP);
+		stream.append(&SHA3_EMPTY);
+		stream.out()
+	}
+}
+
 /// Parameters for a block chain; includes both those intrinsic to the design of the
 /// chain and those to be interpreted by the active chain engine.
 #[derive(Debug)]
@@ -60,14 +81,14 @@ pub struct Spec {
 	pub difficulty: U256,
 	pub gas_limit: U256,
 	pub gas_used: U256,
-	pub timestamp: U256,
+	pub timestamp: u64,
 	pub extra_data: Bytes,
-	pub genesis_state: HashMap<Address, Account>,
+	pub genesis_state: HashMap<Address, GenesisAccount>,
 	pub seal_fields: usize,
 	pub seal_rlp: Bytes,
 
 	// May be prepopulated if we know this in advance.
-	state_root_memo: RefCell<Option<H256>>,
+	state_root_memo: RwLock<Option<H256>>,
 }
 
 impl Spec {
@@ -82,18 +103,18 @@ impl Spec {
 	}
 
 	/// Return the state root for the genesis state, memoising accordingly.
-	pub fn state_root(&self) -> Ref<H256> {
+	pub fn state_root(&self) -> H256 {
-		if self.state_root_memo.borrow().is_none() {
+		if self.state_root_memo.read().unwrap().is_none() {
-			*self.state_root_memo.borrow_mut() = Some(sec_trie_root(self.genesis_state.iter().map(|(k, v)| (k.to_vec(), v.rlp())).collect()));
+			*self.state_root_memo.write().unwrap() = Some(sec_trie_root(self.genesis_state.iter().map(|(k, v)| (k.to_vec(), v.rlp())).collect()));
 		}
-		Ref::map(self.state_root_memo.borrow(), |x|x.as_ref().unwrap())
+		self.state_root_memo.read().unwrap().as_ref().unwrap().clone()
 	}
 
 	pub fn genesis_header(&self) -> Header {
 		Header {
 			parent_hash: self.parent_hash.clone(),
-			timestamp: self.timestamp.clone(),
+			timestamp: self.timestamp,
-			number: U256::from(0u8),
+			number: 0,
 			author: self.author.clone(),
 			transactions_root: SHA3_NULL_RLP.clone(),
 			uncles_hash: RlpStream::new_list(0).out().sha3(),
@@ -113,7 +134,7 @@ impl Spec {
 				let r = Rlp::new(&seal);
 				(0..self.seal_fields).map(|i| r.at(i).as_raw().to_vec()).collect()
 			},
-			hash: RefCell::new(None)
+			hash: RefCell::new(None),
 		}
 	}
 
@@ -149,7 +170,7 @@ impl Spec {
 //				let nonce = if let Some(&Json::String(ref n)) = acc.find("nonce") {U256::from_dec_str(n).unwrap_or(U256::from(0))} else {U256::from(0)};
 				// TODO: handle code & data if they exist.
 				if balance.is_some() || nonce.is_some() {
-					state.insert(addr, Account::new_basic(balance.unwrap_or(U256::from(0)), nonce.unwrap_or(U256::from(0))));
+					state.insert(addr, GenesisAccount { balance: balance.unwrap_or(U256::from(0)), nonce: nonce.unwrap_or(U256::from(0)) });
 				}
 			}
 		}
@@ -181,12 +202,12 @@ impl Spec {
 			difficulty: U256::from_str(&genesis["difficulty"].as_string().unwrap()[2..]).unwrap(),
 			gas_limit: U256::from_str(&genesis["gasLimit"].as_string().unwrap()[2..]).unwrap(),
 			gas_used: U256::from(0u8),
-			timestamp: U256::from_str(&genesis["timestamp"].as_string().unwrap()[2..]).unwrap(),
+			timestamp: u64::from_str(&genesis["timestamp"].as_string().unwrap()[2..]).unwrap(),
 			extra_data: genesis["extraData"].as_string().unwrap()[2..].from_hex().unwrap(),
 			genesis_state: state,
 			seal_fields: seal_fields,
 			seal_rlp: seal_rlp,
-			state_root_memo: RefCell::new(genesis.find("stateRoot").and_then(|_| genesis["stateRoot"].as_string()).map(|s| H256::from_str(&s[2..]).unwrap())),
+			state_root_memo: RwLock::new(genesis.find("stateRoot").and_then(|_| genesis["stateRoot"].as_string()).map(|s| H256::from_str(&s[2..]).unwrap())),
 		}
 	}
 
@@ -228,7 +249,7 @@ mod tests {
 	fn test_chain() {
 		let test_spec = Spec::new_test();
 
-		assert_eq!(*test_spec.state_root(), H256::from_str("f3f4696bbf3b3b07775128eb7a3763279a394e382130f27c21e70233e04946a9").unwrap());
+		assert_eq!(test_spec.state_root(), H256::from_str("f3f4696bbf3b3b07775128eb7a3763279a394e382130f27c21e70233e04946a9").unwrap());
 		let genesis = test_spec.genesis_block();
 		assert_eq!(BlockView::new(&genesis).header_view().sha3(), H256::from_str("0cd786a2425d16f152c658316c423e6ce1181e15c3295826d7c9904cba9ce303").unwrap());
 

src/sync/chain.rs

@@ -16,9 +16,10 @@
 use util::*;
 use std::mem::{replace};
 use views::{HeaderView};
-use header::{Header as BlockHeader};
+use header::{BlockNumber, Header as BlockHeader};
-use client::{BlockNumber, BlockChainClient, BlockStatus, QueueStatus, ImportResult};
+use client::{BlockChainClient, BlockStatus};
 use sync::range_collection::{RangeCollection, ToUsize, FromUsize};
+use error::*;
 use sync::io::SyncIo;
 
 impl ToUsize for BlockNumber {
@@ -76,12 +77,13 @@ struct HeaderId {
 }
 
 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
+/// Sync state 
 pub enum SyncState {
 	/// Initial chain sync has not started yet
 	NotSynced,
 	/// Initial chain sync complete. Waiting for new packets
 	Idle,
-	/// Block downloading paused. Waiting for block queue to process blocks and free space
+	/// Block downloading paused. Waiting for block queue to process blocks and free some space
 	Waiting,
 	/// Downloading blocks
 	Blocks,
@@ -108,24 +110,33 @@ pub struct SyncStatus {
 }
 
 #[derive(PartialEq, Eq, Debug)]
+/// Peer data type requested
 enum PeerAsking {
 	Nothing,
 	BlockHeaders,
 	BlockBodies,
 }
 
+/// Syncing peer information
 struct PeerInfo {
+	/// eth protocol version
 	protocol_version: u32,
+	/// Peer chain genesis hash
 	genesis: H256,
+	/// Peer network id 
 	network_id: U256,
+	/// Peer best block hash
 	latest: H256,
+	/// Peer total difficulty
 	difficulty: U256,
+	/// Type of data currenty being requested from peer.
 	asking: PeerAsking,
+	/// A set of block numbers being requested
 	asking_blocks: Vec<BlockNumber>,
 }
 
-type Body = Bytes;
+/// Blockchain sync handler.
-
+/// See module documentation for more details.
 pub struct ChainSync {
 	/// Sync state
 	state: SyncState,
@@ -140,7 +151,7 @@ pub struct ChainSync {
 	/// Downloaded headers.
 	headers: Vec<(BlockNumber, Vec<Header>)>, //TODO: use BTreeMap once range API is sable. For now it is a vector sorted in descending order
 	/// Downloaded bodies
-	bodies: Vec<(BlockNumber, Vec<Body>)>, //TODO: use BTreeMap once range API is sable. For now it is a vector sorted in descending order
+	bodies: Vec<(BlockNumber, Vec<Bytes>)>, //TODO: use BTreeMap once range API is sable. For now it is a vector sorted in descending order
 	/// Peer info
 	peers: HashMap<PeerId, PeerInfo>,
 	/// Used to map body to header
@@ -390,16 +401,22 @@ impl ChainSync {
 		// TODO: Decompose block and add to self.headers and self.bodies instead
 		if header_view.number() == From::from(self.last_imported_block + 1) {
 			match io.chain().import_block(block_rlp.as_raw()) {
-				ImportResult::AlreadyInChain => {
+				Err(ImportError::AlreadyInChain) => {
 					trace!(target: "sync", "New block already in chain {:?}", h);
 				},
-				ImportResult::AlreadyQueued(_) => {
+				Err(ImportError::AlreadyQueued) => {
 					trace!(target: "sync", "New block already queued {:?}", h);
 				},
-				ImportResult::Queued(QueueStatus::Known) => {
+				Ok(()) => {
 					trace!(target: "sync", "New block queued {:?}", h);
 				},
-				ImportResult::Queued(QueueStatus::Unknown) => {
+				Err(e) => {
+					debug!(target: "sync", "Bad new block {:?} : {:?}", h, e);
+					io.disable_peer(peer_id);
+				}
+			};
+		} 
+		else {
 			trace!(target: "sync", "New block unknown {:?}", h);
 			//TODO: handle too many unknown blocks
 			let difficulty: U256 = try!(r.val_at(1));
@@ -408,12 +425,6 @@ impl ChainSync {
 				trace!(target: "sync", "Received block {:?}  with no known parent. Peer needs syncing...", h);
 				self.sync_peer(io, peer_id, true);
 			}
-				},
-				ImportResult::Bad =>{
-					debug!(target: "sync", "Bad new block {:?}", h);
-					io.disable_peer(peer_id);
-				}
-			};
 		}
 		Ok(())
 	}
@@ -434,7 +445,7 @@ impl ChainSync {
 				BlockStatus::InChain  => {
 					trace!(target: "sync", "New block hash already in chain {:?}", h);
 				},
-				BlockStatus::Queued(_) => {
+				BlockStatus::Queued => {
 					trace!(target: "sync", "New hash block already queued {:?}", h);
 				},
 				BlockStatus::Unknown => {
@@ -642,27 +653,24 @@ impl ChainSync {
 				block_rlp.append_raw(body.at(1).as_raw(), 1);
 				let h = &headers.1[i].hash;
 				match io.chain().import_block(&block_rlp.out()) {
-					ImportResult::AlreadyInChain  => {
+					Err(ImportError::AlreadyInChain) => {
 						trace!(target: "sync", "Block already in chain {:?}", h);
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
 					},
-					ImportResult::AlreadyQueued(_)  => {
+					Err(ImportError::AlreadyQueued) => {
 						trace!(target: "sync", "Block already queued {:?}", h);
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
 					},
-					ImportResult::Queued(QueueStatus::Known) => {
+					Ok(()) => {
 						trace!(target: "sync", "Block queued {:?}", h);
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
 						imported += 1;
 					},
-					ImportResult::Queued(QueueStatus::Unknown) => {
+					Err(e) => {
-						panic!("Queued out of order block");
+						debug!(target: "sync", "Bad block {:?} : {:?}", h, e);
-					},
-					ImportResult::Bad =>{
-						debug!(target: "sync", "Bad block {:?}", h);
 						restart = true;
 					}
 				}

src/sync/io.rs

@@ -2,19 +2,28 @@ use client::BlockChainClient;
 use util::network::{HandlerIo, PeerId, PacketId,};
 use util::error::UtilError;
 
+/// IO interface for the syning handler.
+/// Provides peer connection management and an interface to the blockchain client.
+// TODO: ratings
 pub trait SyncIo {
+	/// Disable a peer
 	fn disable_peer(&mut self, peer_id: &PeerId);
+	/// Respond to current request with a packet. Can be called from an IO handler for incoming packet.
 	fn respond(&mut self, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError>;
+	/// Send a packet to a peer.
 	fn send(&mut self, peer_id: PeerId, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError>;
+	/// Get the blockchain
 	fn chain<'s>(&'s mut self) -> &'s mut BlockChainClient;
 }
 
+/// Wraps `HandlerIo` and the blockchain client
 pub struct NetSyncIo<'s, 'h> where 'h:'s {
 	network: &'s mut HandlerIo<'h>,
 	chain: &'s mut BlockChainClient
 }
 
 impl<'s, 'h> NetSyncIo<'s, 'h> {
+	/// Creates a new instance from the `HandlerIo` and the blockchain client reference.
 	pub fn new(network: &'s mut HandlerIo<'h>, chain: &'s mut BlockChainClient) -> NetSyncIo<'s,'h> {
 		NetSyncIo {
 			network: network,

src/sync/mod.rs

@@ -16,9 +16,8 @@
 ///
 /// fn main() {
 /// 	let mut service = NetworkService::start().unwrap();
-///		let frontier = ethereum::new_frontier();
 /// 	let dir = env::temp_dir();
-/// 	let client = Arc::new(Client::new(&frontier.genesis_block(), &dir));
+/// 	let client = Arc::new(Client::new(ethereum::new_frontier(), &dir).unwrap());
 /// 	EthSync::register(&mut service, client);
 /// }
 /// ```

src/sync/tests.rs

@@ -6,8 +6,8 @@ use util::sha3::Hashable;
 use util::rlp::{self, Rlp, RlpStream, View, Stream};
 use util::network::{PeerId, PacketId};
 use util::error::UtilError;
-use client::{BlockChainClient, BlockStatus, BlockNumber, TreeRoute, BlockQueueStatus, BlockChainInfo, ImportResult, QueueStatus};
+use client::{BlockChainClient, BlockStatus, TreeRoute, BlockQueueStatus, BlockChainInfo, ImportResult};
-use header::Header as BlockHeader;
+use header::{Header as BlockHeader, BlockNumber};
 use sync::io::SyncIo;
 use sync::chain::ChainSync;
 
@@ -39,7 +39,7 @@ impl TestBlockChainClient {
 			let mut header = BlockHeader::new();
 			header.difficulty = From::from(n);
 			header.parent_hash = self.last_hash.clone();
-			header.number = From::from(n);
+			header.number = n as BlockNumber;
 			let mut uncles = RlpStream::new_list(if empty {0} else {1});
 			if !empty {
 				uncles.append(&H256::from(&U256::from(n)));
@@ -49,7 +49,7 @@ impl TestBlockChainClient {
 			rlp.append(&header);
 			rlp.append_raw(&rlp::NULL_RLP, 1);
 			rlp.append_raw(uncles.as_raw(), 1);
-			self.import_block(rlp.as_raw());
+			self.import_block(rlp.as_raw()).unwrap();
 		}
 	}
 }
@@ -100,12 +100,12 @@ impl BlockChainClient for TestBlockChainClient {
 		}
 	}
 
-	fn tree_route(&self, _from: &H256, _to: &H256) -> TreeRoute {
+	fn tree_route(&self, _from: &H256, _to: &H256) -> Option<TreeRoute> {
-		TreeRoute {
+		Some(TreeRoute {
 			blocks: Vec::new(),
 			ancestor: H256::new(),
 			index: 0
-		}
+		})
 	}
 
 	fn state_data(&self, _h: &H256) -> Option<Bytes> {
@@ -118,7 +118,7 @@ impl BlockChainClient for TestBlockChainClient {
 
 	fn import_block(&mut self, b: &[u8]) -> ImportResult {
 		let header = Rlp::new(&b).val_at::<BlockHeader>(0);
-		let number: usize = header.number.low_u64() as usize;
+		let number: usize = header.number as usize;
 		if number > self.blocks.len() {
 			panic!("Unexpected block number. Expected {}, got {}", self.blocks.len(), number);
 		}
@@ -126,7 +126,7 @@ impl BlockChainClient for TestBlockChainClient {
 			match self.blocks.get(&header.parent_hash) {
 				Some(parent) => {
 					let parent = Rlp::new(parent).val_at::<BlockHeader>(0);
-					if parent.number != (header.number - From::from(1)) {
+					if parent.number != (header.number - 1) {
 						panic!("Unexpected block parent");
 					}
 				},
@@ -153,7 +153,7 @@ impl BlockChainClient for TestBlockChainClient {
 		else {
 			self.blocks.insert(header.hash(), b.to_vec());
 		}
-		ImportResult::Queued(QueueStatus::Known)
+		Ok(())
 	}
 
 	fn queue_status(&self) -> BlockQueueStatus {

src/verification.rs

@@ -6,7 +6,6 @@
 /// 3. Final verification against the blockchain done before enactment.
 
 use common::*;
-use client::BlockNumber;
 use engine::Engine;
 use blockchain::BlockChain;
 
@@ -82,12 +81,12 @@ pub fn verify_block_final(bytes: &[u8], engine: &mut Engine, bc: &BlockChain) ->
 			// 6											7
 			//												(8 Invalid)
 
-			let depth = if header.number > uncle.number { header.number - uncle.number } else { From::from(0) };
+			let depth = if header.number > uncle.number { header.number - uncle.number } else { 0 };
-			if depth > From::from(6) {
+			if depth > 6 {
-				return Err(From::from(BlockError::UncleTooOld(OutOfBounds { min: header.number - depth, max: header.number - From::from(1), found: uncle.number })));
+				return Err(From::from(BlockError::UncleTooOld(OutOfBounds { min: header.number - depth, max: header.number - 1, found: uncle.number })));
 			}
-			else if depth < From::from(1) {
+			else if depth < 1 {
-				return Err(From::from(BlockError::UncleIsBrother(OutOfBounds { min: header.number - depth, max: header.number - From::from(1), found: uncle.number })));
+				return Err(From::from(BlockError::UncleIsBrother(OutOfBounds { min: header.number - depth, max: header.number - 1, found: uncle.number })));
 			}
 
 			// cB
@@ -100,7 +99,7 @@ pub fn verify_block_final(bytes: &[u8], engine: &mut Engine, bc: &BlockChain) ->
 			// cB.p^7	-------------/
 			// cB.p^8
 			let mut expected_uncle_parent = header.parent_hash.clone();
-			for _ in 0..depth.as_u32() {
+			for _ in 0..depth {
 				 expected_uncle_parent = bc.block_details(&expected_uncle_parent).unwrap().parent;
 			}
 			if expected_uncle_parent != uncle_parent.hash() {
@@ -116,7 +115,7 @@ pub fn verify_block_final(bytes: &[u8], engine: &mut Engine, bc: &BlockChain) ->
 /// Check basic header parameters.
 fn verify_header(header: &Header) -> Result<(), Error> {
 	if header.number > From::from(BlockNumber::max_value()) {
-		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: From::from(BlockNumber::max_value()), min: From::from(0), found: header.number })))
+		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: From::from(BlockNumber::max_value()), min: 0, found: header.number })))
 	}
 	if header.gas_used > header.gas_limit {
 		return Err(From::from(BlockError::TooMuchGasUsed(OutOfBounds { max: header.gas_limit, min: From::from(0), found: header.gas_used })));
@@ -130,10 +129,10 @@ fn verify_parent(header: &Header, parent: &Header) -> Result<(), Error> {
 		return Err(From::from(BlockError::InvalidParentHash(Mismatch { expected: parent.hash(), found: header.parent_hash.clone() })))
 	}
 	if header.timestamp <= parent.timestamp {
-		return Err(From::from(BlockError::InvalidTimestamp(OutOfBounds { max: BAD_U256, min: parent.timestamp + From::from(1), found: header.timestamp })))
+		return Err(From::from(BlockError::InvalidTimestamp(OutOfBounds { max: u64::max_value(), min: parent.timestamp + 1, found: header.timestamp })))
 	}
 	if header.number <= parent.number {
-		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: From::from(BlockNumber::max_value()), min: parent.number + From::from(1), found: header.number })));
+		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: BlockNumber::max_value(), min: parent.number + 1, found: header.number })));
 	}
 	Ok(())
 }

src/views.rs

@@ -113,7 +113,7 @@ impl<'a> HeaderView<'a> {
 	pub fn difficulty(&self) -> U256 { self.rlp.val_at(7) }
 
 	/// Returns block number.
-	pub fn number(&self) -> U256 { self.rlp.val_at(8) }
+	pub fn number(&self) -> BlockNumber { self.rlp.val_at(8) }
 	
 	/// Returns block gas limit.
 	pub fn gas_limit(&self) -> U256 { self.rlp.val_at(9) }
@@ -122,7 +122,7 @@ impl<'a> HeaderView<'a> {
 	pub fn gas_used(&self) -> U256 { self.rlp.val_at(10) }
 
 	/// Returns timestamp.
-	pub fn timestamp(&self) -> U256 { self.rlp.val_at(11) }
+	pub fn timestamp(&self) -> u64 { self.rlp.val_at(11) }
 
 	/// Returns block extra data.
 	pub fn extra_data(&self) -> Bytes { self.rlp.val_at(12) }