Merge branch 'master' into Dockerfile

.gitignore

@@ -23,4 +23,5 @@ Cargo.lock
 
 /json-tests/target/
 
-
+# jetbrains ide stuff
+.idea

.gitmodules

@@ -1,3 +1,4 @@
 [submodule "res/ethereum/tests"]
 	path = res/ethereum/tests
 	url = git@github.com:ethereum/tests
+	branch = develop

.travis.yml

@@ -0,0 +1,16 @@
+language: rust
+
+rust:
+    - nightly
+
+os:
+    - osx
+
+before_script:
+    - brew update
+    - brew install rocksdb
+
+cache:
+  directories:
+  - $TRAVIS_BUILD_DIR/target
+  - $HOME/.cargo

Cargo.toml

@@ -17,14 +17,13 @@ heapsize = "0.2.0"
 rust-crypto = "0.2.34"
 time = "0.1"
 #interpolate_idents = { git = "https://github.com/SkylerLipthay/interpolate_idents" }
-evmjit = { path = "rust-evmjit", optional = true }
+evmjit = { path = "evmjit", optional = true }
 ethash = { path = "ethash" }
 num_cpus = "0.2"
+clippy = "0.0.37"
+crossbeam = "0.1.5"
 
 [features]
 jit = ["evmjit"]
 evm_debug = []
-
-[[bin]]
-name = "client"
-path = "src/bin/client/main.rs"
+test-heavy = []

bin/Cargo.toml

@@ -0,0 +1,21 @@
+[package]
+description = "Ethcore client."
+name = "ethcore-client"
+version = "0.1.0"
+license = "GPL-3.0"
+authors = ["Ethcore <admin@ethcore.io>"]
+
+[dependencies]
+log = "0.3"
+env_logger = "0.3"
+rustc-serialize = "0.3"
+docopt = "0.6"
+docopt_macros = "0.6"
+ctrlc = "1.0"
+ethcore-util = { path = "../util" }
+ethcore-rpc = { path = "../rpc", optional = true }
+ethcore = { path = ".." }
+clippy = "0.0.37"
+
+[features]
+rpc = ["ethcore-rpc"]

bin/src/main.rs

@@ -0,0 +1,168 @@
+//! Ethcore client application.
+
+#![warn(missing_docs)]
+#![feature(plugin)]
+#![plugin(docopt_macros)]
+#![plugin(clippy)]
+extern crate docopt;
+extern crate rustc_serialize;
+extern crate ethcore_util as util;
+extern crate ethcore;
+extern crate log;
+extern crate env_logger;
+extern crate ctrlc;
+
+#[cfg(feature = "rpc")]
+extern crate ethcore_rpc as rpc;
+
+use std::env;
+use log::{LogLevelFilter};
+use env_logger::LogBuilder;
+use ctrlc::CtrlC;
+use util::*;
+use ethcore::client::*;
+use ethcore::service::{ClientService, NetSyncMessage};
+use ethcore::ethereum;
+use ethcore::blockchain::CacheSize;
+use ethcore::sync::EthSync;
+
+docopt!(Args derive Debug, "
+Parity. Ethereum Client.
+
+Usage:
+  parity [options]
+  parity [options] <enode>...
+
+Options:
+  -l --logging LOGGING  Specify the logging level
+  -h --help             Show this screen.
+");
+
+fn setup_log(init: &str) {
+	let mut builder = LogBuilder::new();
+	builder.filter(None, LogLevelFilter::Info);
+
+	if env::var("RUST_LOG").is_ok() {
+		builder.parse(&env::var("RUST_LOG").unwrap());
+	}
+
+	builder.parse(init);
+
+	builder.init().unwrap();
+}
+
+
+#[cfg(feature = "rpc")]
+fn setup_rpc_server(client: Arc<Client>, sync: Arc<EthSync>) {
+	use rpc::v1::*;
+	
+	let mut server = rpc::HttpServer::new(1);
+	server.add_delegate(Web3Client::new().to_delegate());
+	server.add_delegate(EthClient::new(client.clone()).to_delegate());
+	server.add_delegate(EthFilterClient::new(client).to_delegate());
+	server.add_delegate(NetClient::new(sync).to_delegate());
+	server.start_async("127.0.0.1:3030");
+}
+
+#[cfg(not(feature = "rpc"))]
+fn setup_rpc_server(_client: Arc<Client>, _sync: Arc<EthSync>) {
+}
+
+fn main() {
+	let args: Args = Args::docopt().decode().unwrap_or_else(|e| e.exit());
+
+	setup_log(&args.flag_logging);
+
+	let spec = ethereum::new_frontier();
+	let init_nodes = match args.arg_enode.len() {
+		0 => spec.nodes().clone(),
+		_ => args.arg_enode.clone(),
+	};
+	let mut net_settings = NetworkConfiguration::new();
+	net_settings.boot_nodes = init_nodes;
+	let mut service = ClientService::start(spec, net_settings).unwrap();
+	setup_rpc_server(service.client(), service.sync());
+	let io_handler  = Arc::new(ClientIoHandler { client: service.client(), info: Default::default(), sync: service.sync() });
+	service.io().register_handler(io_handler).expect("Error registering IO handler");
+
+	let exit = Arc::new(Condvar::new());
+	let e = exit.clone();
+	CtrlC::set_handler(move || { e.notify_all(); });
+	let mutex = Mutex::new(());
+	let _ = exit.wait(mutex.lock().unwrap()).unwrap();
+}
+
+struct Informant {
+	chain_info: RwLock<Option<BlockChainInfo>>,
+	cache_info: RwLock<Option<CacheSize>>,
+	report: RwLock<Option<ClientReport>>,
+}
+
+impl Default for Informant {
+	fn default() -> Self {
+		Informant {
+			chain_info: RwLock::new(None),
+			cache_info: RwLock::new(None),
+			report: RwLock::new(None),
+		}
+	}
+}
+
+impl Informant {
+	pub fn tick(&self, client: &Client, sync: &EthSync) {
+		// 5 seconds betwen calls. TODO: calculate this properly.
+		let dur = 5usize;
+
+		let chain_info = client.chain_info();
+		let queue_info = client.queue_info();
+		let cache_info = client.cache_info();
+		let report = client.report();
+		let sync_info = sync.status();
+
+		if let (_, &Some(ref last_cache_info), &Some(ref last_report)) = (self.chain_info.read().unwrap().deref(), self.cache_info.read().unwrap().deref(), self.report.read().unwrap().deref()) {
+			println!("[ {} {} ]---[ {} blk/s | {} tx/s | {} gas/s  //··· {}/{} peers, {} downloaded, {}+{} queued ···//  {} ({}) bl  {} ({}) ex ]",
+				chain_info.best_block_number,
+				chain_info.best_block_hash,
+				(report.blocks_imported - last_report.blocks_imported) / dur,
+				(report.transactions_applied - last_report.transactions_applied) / dur,
+				(report.gas_processed - last_report.gas_processed) / From::from(dur),
+
+				sync_info.num_active_peers,
+				sync_info.num_peers,
+				sync_info.blocks_received,
+				queue_info.unverified_queue_size,
+				queue_info.verified_queue_size,
+
+				cache_info.blocks,
+				cache_info.blocks as isize - last_cache_info.blocks as isize,
+				cache_info.block_details,
+				cache_info.block_details as isize - last_cache_info.block_details as isize
+			);
+		}
+
+		*self.chain_info.write().unwrap().deref_mut() = Some(chain_info);
+		*self.cache_info.write().unwrap().deref_mut() = Some(cache_info);
+		*self.report.write().unwrap().deref_mut() = Some(report);
+	}
+}
+
+const INFO_TIMER: TimerToken = 0;
+
+struct ClientIoHandler {
+	client: Arc<Client>,
+	sync: Arc<EthSync>,
+	info: Informant,
+}
+
+impl IoHandler<NetSyncMessage> for ClientIoHandler {
+	fn initialize(&self, io: &IoContext<NetSyncMessage>) { 
+		io.register_timer(INFO_TIMER, 5000).expect("Error registering timer");
+	}
+
+	fn timeout(&self, _io: &IoContext<NetSyncMessage>, timer: TimerToken) {
+		if INFO_TIMER == timer {
+			self.info.tick(&self.client, &self.sync);
+		}
+	}
+}
+

cov.sh

@@ -17,5 +17,5 @@ fi
 
 cargo test --no-run || exit $?
 mkdir -p target/coverage
-kcov --exclude-pattern ~/.multirust --include-pattern src --verify target/coverage target/debug/ethcore*
+kcov --exclude-pattern ~/.multirust,rocksdb,secp256k1 --include-pattern src --verify target/coverage target/debug/ethcore*
 xdg-open target/coverage/index.html

ethash/src/lib.rs

@@ -30,11 +30,13 @@ impl EthashManager {
 	/// `nonce` - The nonce to pack into the mix
 	pub fn compute_light(&self, block_number: u64, header_hash: &H256, nonce: u64) -> ProofOfWork {
 		let epoch = block_number / ETHASH_EPOCH_LENGTH;
-		if !self.lights.read().unwrap().contains_key(&epoch) {
-			let mut lights = self.lights.write().unwrap(); // obtain write lock
-			if !lights.contains_key(&epoch) {
-				let light = Light::new(block_number);
-				lights.insert(epoch, light);
+		while !self.lights.read().unwrap().contains_key(&epoch) {
+			if let Ok(mut lights) = self.lights.try_write()
+			{
+				if !lights.contains_key(&epoch) {
+					let light = Light::new(block_number);
+					lights.insert(epoch, light);
+				}
 			}
 		}
 		self.lights.read().unwrap().get(&epoch).unwrap().compute(header_hash, nonce)

hook.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+echo "#!/bin/sh\ncargo test" >> ./.git/hooks/pre-push
+chmod +x ./.git/hooks/pre-push

res/ethereum/frontier.json

@@ -26,6 +26,11 @@
 		"gasLimit": "0x1388",
 		"stateRoot": "0xd7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544"
 	},
+	"nodes": [
+		"enode://a979fb575495b8d6db44f750317d0f4622bf4c2aa3365d6af7c284339968eef29b69ad0dce72a4d8db5ebb4968de0e3bec910127f134779fbcb0cb6d3331163c@52.16.188.185:30303",
+		"enode://de471bccee3d042261d52e9bff31458daecc406142b401d4cd848f677479f73104b9fdeb090af9583d3391b7f10cb2ba9e26865dd5fca4fcdc0fb1e3b723c786@54.94.239.50:30303",
+		"enode://1118980bf48b0a3640bdba04e0fe78b1add18e1cd99bf22d53daac1fd9972ad650df52176e7c7d89d1114cfef2bc23a2959aa54998a46afcf7d91809f0855082@52.74.57.123:30303"
+	],
 	"accounts": {
 		"0000000000000000000000000000000000000001": { "builtin": { "name": "ecrecover", "linear": { "base": 3000, "word": 0 } } },
 		"0000000000000000000000000000000000000002": { "builtin": { "name": "sha256", "linear": { "base": 60, "word": 12 } } },

res/ethereum/tests

@@ -1 +1 @@
-Subproject commit dc86e6359675440aea59ddb48648a01c799925d8
+Subproject commit c670b1d8c9f09593a6758ab2c099360e16c7c25b

rpc/Cargo.toml

@@ -0,0 +1,19 @@
+[package]
+description = "Ethcore jsonrpc"
+name = "ethcore-rpc"
+version = "0.1.0"
+license = "GPL-3.0"
+authors = ["Ethcore <admin@ethcore.io"]
+
+[lib]
+
+[dependencies]
+serde = "0.6.7"
+serde_macros = "0.6.10"
+serde_json = "0.6.0"
+jsonrpc-core = "1.1"
+jsonrpc-http-server = "1.1"
+ethcore-util = { path = "../util" }
+ethcore = { path = ".." }
+clippy = "0.0.37"
+

rpc/src/lib.rs

@@ -0,0 +1,43 @@
+//! Ethcore rpc.
+#![warn(missing_docs)]
+#![feature(custom_derive, custom_attribute, plugin)]
+#![plugin(serde_macros)]
+#![plugin(clippy)]
+
+extern crate serde;
+extern crate serde_json;
+extern crate jsonrpc_core;
+extern crate jsonrpc_http_server;
+extern crate ethcore_util as util;
+extern crate ethcore;
+
+use self::jsonrpc_core::{IoHandler, IoDelegate};
+
+pub mod v1;
+
+/// Http server.
+pub struct HttpServer {
+	handler: IoHandler,
+	threads: usize
+}
+
+impl HttpServer {
+	/// Construct new http server object with given number of threads.
+	pub fn new(threads: usize) -> HttpServer {
+		HttpServer {
+			handler: IoHandler::new(),
+			threads: threads
+		}
+	}
+
+	/// Add io delegate.
+	pub fn add_delegate<D>(&mut self, delegate: IoDelegate<D>) where D: Send + Sync + 'static {
+		self.handler.add_delegate(delegate);
+	}
+
+	/// Start server asynchronously in new thread
+	pub fn start_async(self, addr: &str) {
+		let server = jsonrpc_http_server::Server::new(self.handler, self.threads);
+		server.start_async(addr)
+	}
+}

rpc/src/v1/impls/eth.rs

@@ -0,0 +1,132 @@
+//! Eth rpc implementation.
+use std::sync::Arc;
+use jsonrpc_core::*;
+use util::hash::*;
+use util::uint::*;
+use util::sha3::*;
+use ethcore::client::*;
+use ethcore::views::*;
+use v1::traits::{Eth, EthFilter};
+use v1::types::Block;
+
+/// Eth rpc implementation.
+pub struct EthClient {
+	client: Arc<Client>,
+}
+
+impl EthClient {
+	/// Creates new EthClient.
+	pub fn new(client: Arc<Client>) -> Self {
+		EthClient {
+			client: client
+		}
+	}
+}
+
+impl Eth for EthClient {
+	fn protocol_version(&self, params: Params) -> Result<Value, Error> {
+		match params {
+			Params::None => Ok(Value::U64(63)),
+			_ => Err(Error::invalid_params())
+		}
+	}
+
+	fn author(&self, params: Params) -> Result<Value, Error> {
+		match params {
+			Params::None => to_value(&Address::new()),
+			_ => Err(Error::invalid_params())
+		}
+	}
+
+	fn gas_price(&self, params: Params) -> Result<Value, Error> {
+		match params {
+			Params::None => Ok(Value::U64(0)),
+			_ => Err(Error::invalid_params())
+		}
+	}
+
+	fn block_number(&self, params: Params) -> Result<Value, Error> {
+		match params {
+			Params::None => Ok(Value::U64(self.client.chain_info().best_block_number)),
+			_ => Err(Error::invalid_params())
+		}
+	}
+
+	fn is_mining(&self, params: Params) -> Result<Value, Error> {
+		match params {
+			Params::None => Ok(Value::Bool(false)),
+			_ => Err(Error::invalid_params())
+		}
+	}
+
+	fn hashrate(&self, params: Params) -> Result<Value, Error> {
+		match params {
+			Params::None => Ok(Value::U64(0)),
+			_ => Err(Error::invalid_params())
+		}
+	}
+
+	fn block_transaction_count(&self, _: Params) -> Result<Value, Error> {
+		Ok(Value::U64(0))
+	}
+
+	fn block(&self, params: Params) -> Result<Value, Error> {
+		match from_params::<(H256, bool)>(params) {
+			Ok((hash, _include_txs)) => match (self.client.block_header(&hash), self.client.block_total_difficulty(&hash)) {
+				(Some(bytes), Some(total_difficulty)) => {
+					let view = HeaderView::new(&bytes);
+					let block = Block {
+						hash: view.sha3(),
+						parent_hash: view.parent_hash(),
+						uncles_hash: view.uncles_hash(),
+						author: view.author(),
+						miner: view.author(),
+						state_root: view.state_root(),
+						transactions_root: view.transactions_root(),
+						receipts_root: view.receipts_root(),
+						number: U256::from(view.number()),
+						gas_used: view.gas_used(),
+						gas_limit: view.gas_limit(),
+						logs_bloom: view.log_bloom(),
+						timestamp: U256::from(view.timestamp()),
+						difficulty: view.difficulty(),
+						total_difficulty: total_difficulty,
+						uncles: vec![],
+						transactions: vec![]
+					};
+					to_value(&block)
+				},
+				_ => Ok(Value::Null)
+			},
+			Err(err) => Err(err)
+		}
+	}
+}
+
+/// Eth filter rpc implementation.
+pub struct EthFilterClient {
+	client: Arc<Client>
+}
+
+impl EthFilterClient {
+	/// Creates new Eth filter client.
+	pub fn new(client: Arc<Client>) -> Self {
+		EthFilterClient {
+			client: client
+		}
+	}
+}
+
+impl EthFilter for EthFilterClient {
+	fn new_block_filter(&self, _params: Params) -> Result<Value, Error> {
+		Ok(Value::U64(0))
+	}
+
+	fn new_pending_transaction_filter(&self, _params: Params) -> Result<Value, Error> {
+		Ok(Value::U64(1))
+	}
+
+	fn filter_changes(&self, _: Params) -> Result<Value, Error> {
+		to_value(&self.client.chain_info().best_block_hash).map(|v| Value::Array(vec![v]))
+	}
+}

rpc/src/v1/impls/mod.rs

@@ -0,0 +1,8 @@
+//! Ethereum rpc interface implementation.
+mod web3;
+mod eth;
+mod net;
+
+pub use self::web3::Web3Client;
+pub use self::eth::{EthClient, EthFilterClient};
+pub use self::net::NetClient;

rpc/src/v1/impls/net.rs

@@ -0,0 +1,29 @@
+//! Net rpc implementation.
+use std::sync::Arc;
+use jsonrpc_core::*;
+use ethcore::sync::EthSync;
+use v1::traits::Net;
+
+/// Net rpc implementation.
+pub struct NetClient {
+	sync: Arc<EthSync>
+}
+
+impl NetClient {
+	/// Creates new NetClient.
+	pub fn new(sync: Arc<EthSync>) -> Self { 
+		NetClient {
+			sync: sync
+		}
+	}
+}
+
+impl Net for NetClient {
+	fn version(&self, _: Params) -> Result<Value, Error> {
+		Ok(Value::U64(self.sync.status().protocol_version as u64))
+	}
+
+	fn peer_count(&self, _params: Params) -> Result<Value, Error> {
+		Ok(Value::U64(self.sync.status().num_peers as u64))
+	}
+}

rpc/src/v1/impls/web3.rs

@@ -0,0 +1,21 @@
+//! Web3 rpc implementation.
+use jsonrpc_core::*;
+use v1::traits::Web3;
+
+/// Web3 rpc implementation.
+pub struct Web3Client;
+
+impl Web3Client {
+	/// Creates new Web3Client.
+	pub fn new() -> Self { Web3Client }
+}
+
+impl Web3 for Web3Client {
+	fn client_version(&self, params: Params) -> Result<Value, Error> {
+		match params {
+			//Params::None => Ok(Value::String("parity/0.1.0/-/rust1.7-nightly".to_owned())),
+			Params::None => Ok(Value::String("surprise/0.1.0/surprise/surprise".to_owned())),
+			_ => Err(Error::invalid_params())
+		}
+	}
+}

rpc/src/v1/mod.rs

@@ -0,0 +1,10 @@
+//! Ethcore rpc v1.
+//! 
+//! Compliant with ethereum rpc.
+
+pub mod traits;
+mod impls;
+mod types;
+
+pub use self::traits::{Web3, Eth, EthFilter, Net};
+pub use self::impls::*;

rpc/src/v1/traits/eth.rs

@@ -0,0 +1,163 @@
+//! Eth rpc interface.
+use std::sync::Arc;
+use jsonrpc_core::*;
+
+/// Eth rpc interface.
+pub trait Eth: Sized + Send + Sync + 'static {
+	/// Returns protocol version.
+	fn protocol_version(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns the number of hashes per second that the node is mining with.
+	fn hashrate(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns block author.
+	fn author(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns true if client is actively mining new blocks.
+	fn is_mining(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns current gas_price.
+	fn gas_price(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns accounts list.
+	fn accounts(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns highest block number.
+	fn block_number(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns balance of the given account.
+	fn balance(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns content of the storage at given address.
+	fn storage_at(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns block with given index / hash.
+	fn block(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+	
+	/// Returns the number of transactions sent from given address at given time (block number).
+	fn transaction_count(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns the number of transactions in a block.
+	fn block_transaction_count(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns the number of uncles in a given block.
+	fn block_uncles_count(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns the code at given address at given time (block number).
+	fn code_at(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Sends transaction.
+	fn send_transaction(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Call contract.
+	fn call(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Estimate gas needed for execution of given contract.
+	fn estimate_gas(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns transaction at given block and index.
+	fn transaction_at(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns transaction receipt.
+	fn transaction_receipt(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns an uncles at given block and index.
+	fn uncle_at(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns available compilers.
+	fn compilers(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Compiles lll code.
+	fn compile_lll(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Compiles solidity.
+	fn compile_solidity(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Compiles serpent.
+	fn compile_serpent(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns logs matching given filter object.
+	fn logs(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns the hash of the current block, the seedHash, and the boundary condition to be met.
+	fn work(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Used for submitting a proof-of-work solution.
+	fn submit_work(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Used for submitting mining hashrate.
+	fn submit_hashrate(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Should be used to convert object to io delegate.
+	fn to_delegate(self) -> IoDelegate<Self> {
+		let mut delegate = IoDelegate::new(Arc::new(self));
+		delegate.add_method("eth_protocolVersion", Eth::protocol_version);
+		delegate.add_method("eth_hashrate", Eth::hashrate);
+		delegate.add_method("eth_coinbase", Eth::author);
+		delegate.add_method("eth_mining", Eth::is_mining);
+		delegate.add_method("eth_gasPrice", Eth::gas_price);
+		delegate.add_method("eth_accounts", Eth::accounts);
+		delegate.add_method("eth_blockNumber", Eth::block_number);
+		delegate.add_method("eth_balance", Eth::balance);
+		delegate.add_method("eth_getStorageAt", Eth::storage_at);
+		delegate.add_method("eth_getTransactionCount", Eth::transaction_count);
+		delegate.add_method("eth_getBlockTransactionCountByHash", Eth::block_transaction_count);
+		delegate.add_method("eth_getBlockTransactionCountByNumber", Eth::block_transaction_count);
+		delegate.add_method("eth_getUncleCountByBlockHash", Eth::block_uncles_count);
+		delegate.add_method("eth_getUncleCountByBlockNumber", Eth::block_uncles_count);
+		delegate.add_method("eth_code", Eth::code_at);
+		delegate.add_method("eth_sendTransaction", Eth::send_transaction);
+		delegate.add_method("eth_call", Eth::call);
+		delegate.add_method("eth_estimateGas", Eth::estimate_gas);
+		delegate.add_method("eth_getBlockByHash", Eth::block);
+		delegate.add_method("eth_getBlockByNumber", Eth::block);
+		delegate.add_method("eth_getTransactionByBlockHashAndIndex", Eth::transaction_at);
+		delegate.add_method("eth_getTransactionByBlockNumberAndIndex", Eth::transaction_at);
+		delegate.add_method("eth_getTransactionReceipt", Eth::transaction_receipt);
+		delegate.add_method("eth_getUncleByBlockHashAndIndex", Eth::uncle_at);
+		delegate.add_method("eth_getUncleByBlockNumberAndIndex", Eth::uncle_at);
+		delegate.add_method("eth_getCompilers", Eth::compilers);
+		delegate.add_method("eth_compileLLL", Eth::compile_lll);
+		delegate.add_method("eth_compileSolidity", Eth::compile_solidity);
+		delegate.add_method("eth_compileSerpent", Eth::compile_serpent);
+		delegate.add_method("eth_getLogs", Eth::logs);
+		delegate.add_method("eth_getWork", Eth::work);
+		delegate.add_method("eth_submitWork", Eth::submit_work);
+		delegate.add_method("eth_submitHashrate", Eth::submit_hashrate);
+		delegate
+	}
+}
+
+/// Eth filters rpc api (polling).
+// TODO: do filters api properly
+pub trait EthFilter: Sized + Send + Sync + 'static {
+	/// Returns id of new filter.
+	fn new_filter(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns id of new block filter.
+	fn new_block_filter(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns id of new block filter.
+	fn new_pending_transaction_filter(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns filter changes since last poll.
+	fn filter_changes(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns filter logs.
+	fn filter_logs(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Uninstalls filter.
+	fn uninstall_filter(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Should be used to convert object to io delegate.
+	fn to_delegate(self) -> IoDelegate<Self> {
+		let mut delegate = IoDelegate::new(Arc::new(self));
+		delegate.add_method("eth_newFilter", EthFilter::new_filter);
+		delegate.add_method("eth_newBlockFilter", EthFilter::new_block_filter);
+		delegate.add_method("eth_newPendingTransactionFilter", EthFilter::new_pending_transaction_filter);
+		delegate.add_method("eth_getFilterChanges", EthFilter::filter_changes);
+		delegate.add_method("eth_getFilterLogs", EthFilter::filter_logs);
+		delegate.add_method("eth_uninstallFilter", EthFilter::uninstall_filter);
+		delegate
+	}
+}

rpc/src/v1/traits/mod.rs

@@ -0,0 +1,13 @@
+//! Ethereum rpc interfaces.
+
+macro_rules! rpc_unimplemented {
+	() => (Err(Error::internal_error()))
+}
+
+pub mod web3;
+pub mod eth;
+pub mod net;
+
+pub use self::web3::Web3;
+pub use self::eth::{Eth, EthFilter};
+pub use self::net::Net;

rpc/src/v1/traits/net.rs

@@ -0,0 +1,25 @@
+//! Net rpc interface.
+use std::sync::Arc;
+use jsonrpc_core::*;
+
+/// Net rpc interface.
+pub trait Net: Sized + Send + Sync + 'static {
+	/// Returns protocol version.
+	fn version(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns number of peers connected to node.
+	fn peer_count(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Returns true if client is actively listening for network connections.
+	/// Otherwise false.
+	fn is_listening(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Should be used to convert object to io delegate.
+	fn to_delegate(self) -> IoDelegate<Self> {
+		let mut delegate = IoDelegate::new(Arc::new(self));
+		delegate.add_method("net_version", Net::version);
+		delegate.add_method("net_peerCount", Net::peer_count);
+		delegate.add_method("net_listening", Net::is_listening);
+		delegate
+	}
+}

rpc/src/v1/traits/web3.rs

@@ -0,0 +1,16 @@
+//! Web3 rpc interface.
+use std::sync::Arc;
+use jsonrpc_core::*;
+
+/// Web3 rpc interface.
+pub trait Web3: Sized + Send + Sync + 'static {
+	/// Returns current client version.
+	fn client_version(&self, _: Params) -> Result<Value, Error> { rpc_unimplemented!() }
+
+	/// Should be used to convert object to io delegate.
+	fn to_delegate(self) -> IoDelegate<Self> {
+		let mut delegate = IoDelegate::new(Arc::new(self));
+		delegate.add_method("web3_clientVersion", Web3::client_version);
+		delegate
+	}
+}

rpc/src/v1/types/block.rs

@@ -0,0 +1,36 @@
+use util::hash::*;
+use util::uint::*;
+
+#[derive(Default, Debug, Serialize)]
+pub struct Block {
+	pub hash: H256,
+	#[serde(rename="parentHash")]
+	pub parent_hash: H256,
+	#[serde(rename="sha3Uncles")]
+	pub uncles_hash: H256,
+	pub author: Address,
+	// TODO: get rid of this one
+	pub miner: Address,
+	#[serde(rename="stateRoot")]
+	pub state_root: H256,
+	#[serde(rename="transactionsRoot")]
+	pub transactions_root: H256,
+	#[serde(rename="receiptsRoot")]
+	pub receipts_root: H256,
+	pub number: U256,
+	#[serde(rename="gasUsed")]
+	pub gas_used: U256,
+	#[serde(rename="gasLimit")]
+	pub gas_limit: U256,
+	// TODO: figure out how to properly serialize bytes
+	//#[serde(rename="extraData")]
+	//extra_data: Vec<u8>,
+	#[serde(rename="logsBloom")]
+	pub logs_bloom: H2048,
+	pub timestamp: U256,
+	pub difficulty: U256,
+	#[serde(rename="totalDifficulty")]
+	pub total_difficulty: U256,
+	pub uncles: Vec<U256>,
+	pub transactions: Vec<U256>
+}

rpc/src/v1/types/mod.rs

@@ -0,0 +1,3 @@
+mod block;
+
+pub use self::block::Block;

src/account.rs

@@ -103,7 +103,7 @@ impl Account {
 	/// Get (and cache) the contents of the trie's storage at `key`.
 	pub fn storage_at(&self, db: &HashDB, key: &H256) -> H256 {
 		self.storage_overlay.borrow_mut().entry(key.clone()).or_insert_with(||{
-			(Filth::Clean, H256::from(SecTrieDB::new(db, &self.storage_root).get(key.bytes()).map(|v| -> U256 {decode(v)}).unwrap_or(U256::zero())))
+			(Filth::Clean, H256::from(SecTrieDB::new(db, &self.storage_root).get(key.bytes()).map_or(U256::zero(), |v| -> U256 {decode(v)})))
 		}).1.clone()
 	}
 
@@ -149,11 +149,15 @@ impl Account {
 	/// Provide a database to lookup `code_hash`. Should not be called if it is a contract without code.
 	pub fn cache_code(&mut self, db: &HashDB) -> bool {
 		// TODO: fill out self.code_cache;
-		return self.is_cached() ||
+		trace!("Account::cache_code: ic={}; self.code_hash={:?}, self.code_cache={}", self.is_cached(), self.code_hash, self.code_cache.pretty());
+		self.is_cached() ||
 			match self.code_hash {
 				Some(ref h) => match db.lookup(h) {
 					Some(x) => { self.code_cache = x.to_vec(); true },
-					_ => false,
+					_ => {
+						warn!("Failed reverse lookup of {}", h);
+						false
+					},
 				},
 				_ => false,
 			}
@@ -248,8 +252,8 @@ mod tests {
 
 		let a = Account::from_rlp(&rlp);
 		assert_eq!(a.storage_root().unwrap().hex(), "c57e1afb758b07f8d2c8f13a3b6e44fa5ff94ab266facc5a4fd3f062426e50b2");
-		assert_eq!(a.storage_at(&mut db, &H256::from(&U256::from(0x00u64))), H256::from(&U256::from(0x1234u64)));
-		assert_eq!(a.storage_at(&mut db, &H256::from(&U256::from(0x01u64))), H256::new());
+		assert_eq!(a.storage_at(&db, &H256::from(&U256::from(0x00u64))), H256::from(&U256::from(0x1234u64)));
+		assert_eq!(a.storage_at(&db, &H256::from(&U256::from(0x01u64))), H256::new());
 	}
 
 	#[test]

src/account_diff.rs

@@ -15,10 +15,10 @@ pub enum Existance {
 
 impl fmt::Display for Existance {
 	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-		match self {
-			&Existance::Born => try!(write!(f, "+++")),
-			&Existance::Alive => try!(write!(f, "***")),
-			&Existance::Died => try!(write!(f, "XXX")),
+		match *self {
+			Existance::Born => try!(write!(f, "+++")),
+			Existance::Alive => try!(write!(f, "***")),
+			Existance::Died => try!(write!(f, "XXX")),
 		}
 		Ok(())
 	}
@@ -72,11 +72,11 @@ impl AccountDiff {
 					code: Diff::new(pre.code.clone(), post.code.clone()),
 					storage: storage.into_iter().map(|k|
 						(k.clone(), Diff::new(
-							pre.storage.get(&k).cloned().unwrap_or(H256::new()),
-							post.storage.get(&k).cloned().unwrap_or(H256::new())
+							pre.storage.get(&k).cloned().unwrap_or_else(H256::new),
+							post.storage.get(&k).cloned().unwrap_or_else(H256::new)
 						))).collect(),
 				};
-				if r.balance.is_same() && r.nonce.is_same() && r.code.is_same() && r.storage.len() == 0 {
+				if r.balance.is_same() && r.nonce.is_same() && r.code.is_same() && r.storage.is_empty() {
 					None
 				} else {
 					Some(r)
@@ -112,16 +112,15 @@ impl fmt::Display for AccountDiff {
 			Diff::Changed(ref pre, ref post) => try!(write!(f, "${} ({} {} {})", post, pre, if pre > post {"-"} else {"+"}, *max(pre, post) - *min(pre, post))),
 			_ => {},
 		}
-		match self.code {
-			Diff::Born(ref x) => try!(write!(f, "  code {}", x.pretty())),
-			_ => {},
+		if let Diff::Born(ref x) = self.code {
+			try!(write!(f, "  code {}", x.pretty()));
 		}
 		try!(write!(f, "\n"));
-		for (k, dv) in self.storage.iter() {
-			match dv {
-				&Diff::Born(ref v) => try!(write!(f, "    +  {} => {}\n", interpreted_hash(k), interpreted_hash(v))),
-				&Diff::Changed(ref pre, ref post) => try!(write!(f, "    *  {} => {} (was {})\n", interpreted_hash(k), interpreted_hash(post), interpreted_hash(pre))),
-				&Diff::Died(_) => try!(write!(f, "    X  {}\n", interpreted_hash(k))),
+		for (k, dv) in &self.storage {
+			match *dv {
+				Diff::Born(ref v) => try!(write!(f, "    +  {} => {}\n", interpreted_hash(k), interpreted_hash(v))),
+				Diff::Changed(ref pre, ref post) => try!(write!(f, "    *  {} => {} (was {})\n", interpreted_hash(k), interpreted_hash(post), interpreted_hash(pre))),
+				Diff::Died(_) => try!(write!(f, "    X  {}\n", interpreted_hash(k))),
 				_ => {},
 			}
 		}

src/action_params.rs

@@ -3,8 +3,16 @@ use util::hash::*;
 use util::uint::*;
 use util::bytes::*;
 
-// TODO: should be a trait, possible to avoid cloning everything from a Transaction(/View).
+/// Transaction value
+#[derive(Clone, Debug)]
+pub enum ActionValue {
+	/// Value that should be transfered
+	Transfer(U256),
+	/// Apparent value for transaction (not transfered)
+	Apparent(U256)
+}
 
+// TODO: should be a trait, possible to avoid cloning everything from a Transaction(/View).
 /// Action (call/create) input params. Everything else should be specified in Externalities.
 #[derive(Clone, Debug)]
 pub struct ActionParams {
@@ -22,16 +30,16 @@ pub struct ActionParams {
 	/// Gas price.
 	pub gas_price: U256,
 	/// Transaction value.
-	pub value: U256,
+	pub value: ActionValue,
 	/// Code being executed.
 	pub code: Option<Bytes>,
 	/// Input data.
 	pub data: Option<Bytes>
 }
 
-impl ActionParams {
-	/// TODO [Gav Wood] Please document me
-	pub fn new() -> ActionParams {
+impl Default for ActionParams {
+	/// Returns default ActionParams initialized with zeros
+	fn default() -> ActionParams {
 		ActionParams {
 			code_address: Address::new(),
 			address: Address::new(),
@@ -39,7 +47,7 @@ impl ActionParams {
 			origin: Address::new(),
 			gas: U256::zero(),
 			gas_price: U256::zero(),
-			value: U256::zero(),
+			value: ActionValue::Transfer(U256::zero()),
 			code: None,
 			data: None
 		}

src/bin/client/main.rs

@@ -1,100 +0,0 @@
-extern crate ethcore_util as util;
-extern crate ethcore;
-extern crate rustc_serialize;
-extern crate log;
-extern crate env_logger;
-
-use std::io::stdin;
-use std::env;
-use log::{LogLevelFilter};
-use env_logger::LogBuilder;
-use util::*;
-use ethcore::client::*;
-use ethcore::service::ClientService;
-use ethcore::ethereum;
-use ethcore::blockchain::CacheSize;
-use ethcore::sync::*;
-
-fn setup_log() {
-	let mut builder = LogBuilder::new();
-	builder.filter(None, LogLevelFilter::Info);
-
-	if env::var("RUST_LOG").is_ok() {
-		builder.parse(&env::var("RUST_LOG").unwrap());
-	}
-
-	builder.init().unwrap();
-}
-
-fn main() {
-	setup_log();
-	let spec = ethereum::new_frontier();
-	let mut service = ClientService::start(spec).unwrap();
-	let io_handler  = Box::new(ClientIoHandler { client: service.client(), timer: 0, info: Default::default() });
-	service.io().register_handler(io_handler).expect("Error registering IO handler");
-	loop {
-		let mut cmd = String::new();
-		stdin().read_line(&mut cmd).unwrap();
-		if cmd == "quit\n" || cmd == "exit\n" || cmd == "q\n" {
-			break;
-		}
-	}
-}
-
-#[derive(Default, Debug)]
-struct Informant {
-	chain_info: Option<BlockChainInfo>,
-	cache_info: Option<CacheSize>,
-	report: Option<ClientReport>,
-}
-
-impl Informant {
-	pub fn tick(&mut self, client: &Client) {
-		// 5 seconds betwen calls. TODO: calculate this properly.
-		let dur = 5usize;
-
-		let chain_info = client.chain_info();
-		let cache_info = client.cache_info();
-		let report = client.report();
-
-		if let (_, &Some(ref last_cache_info), &Some(ref last_report)) = (&self.chain_info, &self.cache_info, &self.report) {
-			println!("[ {} {} ]---[ {} blk/s | {} tx/s | {} gas/s  //···{}···//  {} ({}) bl  {} ({}) ex ]",
-				chain_info.best_block_number,
-				chain_info.best_block_hash,
-				(report.blocks_imported - last_report.blocks_imported) / dur,
-				(report.transactions_applied - last_report.transactions_applied) / dur,
-				(report.gas_processed - last_report.gas_processed) / From::from(dur),
-				0, // TODO: peers
-				cache_info.blocks,
-				cache_info.blocks as isize - last_cache_info.blocks as isize,
-				cache_info.block_details,
-				cache_info.block_details as isize - last_cache_info.block_details as isize
-			);
-		}
-
-		self.chain_info = Some(chain_info);
-		self.cache_info = Some(cache_info);
-		self.report = Some(report);
-	}
-}
-
-struct ClientIoHandler {
-	client: Arc<RwLock<Client>>,
-	timer: TimerToken,
-	info: Informant,
-}
-
-impl IoHandler<NetSyncMessage> for ClientIoHandler {
-	fn initialize<'s>(&'s mut self, io: &mut IoContext<'s, NetSyncMessage>) { 
-		self.timer = io.register_timer(5000).expect("Error registering timer");
-	}
-
-	fn timeout<'s>(&'s mut self, _io: &mut IoContext<'s, NetSyncMessage>, timer: TimerToken) {
-		if self.timer == timer {
-			let client = self.client.read().unwrap();
-			client.tick();
-			self.info.tick(client.deref());
-		}
-	}
-}
-

src/block.rs

@@ -1,82 +1,128 @@
+#![allow(ptr_arg)] // Because of &LastHashes -> &Vec<_>
+
 use common::*;
 use engine::*;
 use state::*;
 use verification::PreVerifiedBlock;
 
-/// A transaction/receipt execution entry.
-pub struct Entry {
-	transaction: Transaction,
-	receipt: Receipt,
+/// A block, encoded as it is on the block chain.
+// TODO: rename to Block
+#[derive(Default, Debug, Clone)]
+pub struct Block {
+	/// The header of this block.
+	pub header: Header,
+	/// The transactions in this block.
+	pub transactions: Vec<Transaction>,
+	/// The uncles of this block.
+	pub uncles: Vec<Header>,
+}
+
+impl Block {
+	/// Returns true iff the given bytes form a valid encoding of a block in RLP.
+	// TODO: implement Decoder for this and have this use that.
+	pub fn is_good(b: &[u8]) -> bool {
+		/*
+		let urlp = UntrustedRlp::new(&b);
+		if !urlp.is_list() || urlp.item_count() != 3 || urlp.size() != b.len() { return false; }
+		if urlp.val_at::<Header>(0).is_err() { return false; }
+
+		if !urlp.at(1).unwrap().is_list() { return false; }
+		if urlp.at(1).unwrap().iter().find(|i| i.as_val::<Transaction>().is_err()).is_some() {
+			return false;
+		}
+		
+		if !urlp.at(2).unwrap().is_list() { return false; }
+		if urlp.at(2).unwrap().iter().find(|i| i.as_val::<Header>().is_err()).is_some() {
+			return false;
+		}
+		true*/
+		UntrustedRlp::new(b).as_val::<Block>().is_ok()
+	}
+}
+
+impl Decodable for Block {
+	fn decode<D>(decoder: &D) -> Result<Self, DecoderError> where D: Decoder {
+		if decoder.as_raw().len() != try!(decoder.as_rlp().payload_info()).total() {
+			return Err(DecoderError::RlpIsTooBig);	
+		}
+		let d = try!(decoder.as_list());
+		if d.len() != 3 {
+			return Err(DecoderError::RlpIncorrectListLen);
+		}
+		Ok(Block {
+			header: try!(Decodable::decode(&d[0])),
+			transactions: try!(Decodable::decode(&d[1])),
+			uncles: try!(Decodable::decode(&d[2])),
+		})
+	}
 }
 
 /// Internal type for a block's common elements.
-pub struct Block {
-	header: Header,
+// TODO: rename to ExecutedBlock
+// TODO: use BareBlock
+#[derive(Debug, Clone)]
+pub struct ExecutedBlock {
+	base: Block,
 
-	/// State is the most final state in the block.
+	receipts: Vec<Receipt>,
+	transactions_set: HashSet<H256>,
 	state: State,
-
-	archive: Vec<Entry>,
-	archive_set: HashSet<H256>,
-
-	uncles: Vec<Header>,
 }
 
-/// A set of references to `Block` fields that are publicly accessible. 
+/// A set of references to `ExecutedBlock` fields that are publicly accessible. 
 pub struct BlockRefMut<'a> {
 	/// TODO [Gav Wood] Please document me
 	pub header: &'a Header,
 	/// TODO [Gav Wood] Please document me
-	pub state: &'a mut State,
-	/// TODO [Gav Wood] Please document me
-	pub archive: &'a Vec<Entry>,
+	pub transactions: &'a Vec<Transaction>,
 	/// TODO [Gav Wood] Please document me
 	pub uncles: &'a Vec<Header>,
+
+	/// TODO [Gav Wood] Please document me
+	pub receipts: &'a Vec<Receipt>,
+	/// TODO [Gav Wood] Please document me
+	pub state: &'a mut State,
 }
 
-impl Block {
+impl ExecutedBlock {
 	/// Create a new block from the given `state`.
-	fn new(state: State) -> Block {
-		Block {
-			header: Header::new(),
-			state: state,
-			archive: Vec::new(),
-			archive_set: HashSet::new(),
-			uncles: Vec::new(),
-		}
-	}
+	fn new(state: State) -> ExecutedBlock { ExecutedBlock { base: Default::default(), receipts: Default::default(), transactions_set: Default::default(), state: state } }
 
 	/// Get a structure containing individual references to all public fields.
 	pub fn fields(&mut self) -> BlockRefMut {
 		BlockRefMut {
-			header: &self.header,
+			header: &self.base.header,
+			transactions: &self.base.transactions,
+			uncles: &self.base.uncles,
 			state: &mut self.state,
-			archive: &self.archive,
-			uncles: &self.uncles,
+			receipts: &self.receipts,
 		}
 	}
 }
 
-/// Trait for a object that is_a `Block`.
+/// Trait for a object that is_a `ExecutedBlock`.
 pub trait IsBlock {
 	/// Get the block associated with this object.
-	fn block(&self) -> &Block;
+	fn block(&self) -> &ExecutedBlock;
 
 	/// Get the header associated with this object's block.
-	fn header(&self) -> &Header { &self.block().header }
+	fn header(&self) -> &Header { &self.block().base.header }
 
 	/// Get the final state associated with this object's block.
 	fn state(&self) -> &State { &self.block().state }
 
 	/// Get all information on transactions in this block.
-	fn archive(&self) -> &Vec<Entry> { &self.block().archive }
+	fn transactions(&self) -> &Vec<Transaction> { &self.block().base.transactions }
+
+	/// Get all information on receipts in this block.
+	fn receipts(&self) -> &Vec<Receipt> { &self.block().receipts }
 
 	/// Get all uncles in this block.
-	fn uncles(&self) -> &Vec<Header> { &self.block().uncles }
+	fn uncles(&self) -> &Vec<Header> { &self.block().base.uncles }
 }
 
-impl IsBlock for Block {
-	fn block(&self) -> &Block { self }
+impl IsBlock for ExecutedBlock {
+	fn block(&self) -> &ExecutedBlock { self }
 }
 
 /// Block that is ready for transactions to be added.
@@ -84,7 +130,7 @@ 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<'x, 'y> {
-	block: Block,
+	block: ExecutedBlock,
 	engine: &'x Engine,
 	last_hashes: &'y LastHashes,
 }
@@ -102,7 +148,7 @@ pub struct ClosedBlock<'x, 'y> {
 ///
 /// The block's header has valid seal arguments. The block cannot be reversed into a ClosedBlock or OpenBlock.
 pub struct SealedBlock {
-	block: Block,
+	block: ExecutedBlock,
 	uncle_bytes: Bytes,
 }
 
@@ -110,42 +156,42 @@ impl<'x, 'y> OpenBlock<'x, 'y> {
 	/// Create a new OpenBlock ready for transaction pushing.
 	pub fn new<'a, 'b>(engine: &'a Engine, db: JournalDB, 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())),
+			block: ExecutedBlock::new(State::from_existing(db, parent.state_root().clone(), engine.account_start_nonce())),
 			engine: engine,
 			last_hashes: last_hashes,
 		};
 
-		r.block.header.set_number(parent.number() + 1);
-		r.block.header.set_author(author);
-		r.block.header.set_extra_data(extra_data);
-		r.block.header.set_timestamp_now();
+		r.block.base.header.set_number(parent.number() + 1);
+		r.block.base.header.set_author(author);
+		r.block.base.header.set_extra_data(extra_data);
+		r.block.base.header.set_timestamp_now();
 
-		engine.populate_from_parent(&mut r.block.header, parent);
+		engine.populate_from_parent(&mut r.block.base.header, parent);
 		engine.on_new_block(&mut r.block);
 		r
 	}
 
 	/// Alter the author for the block.
-	pub fn set_author(&mut self, author: Address) { self.block.header.set_author(author); }
+	pub fn set_author(&mut self, author: Address) { self.block.base.header.set_author(author); }
 
 	/// Alter the timestamp of the block.
-	pub fn set_timestamp(&mut self, timestamp: u64) { self.block.header.set_timestamp(timestamp); }
+	pub fn set_timestamp(&mut self, timestamp: u64) { self.block.base.header.set_timestamp(timestamp); }
 
 	/// Alter the difficulty for the block.
-	pub fn set_difficulty(&mut self, a: U256) { self.block.header.set_difficulty(a); }
+	pub fn set_difficulty(&mut self, a: U256) { self.block.base.header.set_difficulty(a); }
 
 	/// Alter the gas limit for the block.
-	pub fn set_gas_limit(&mut self, a: U256) { self.block.header.set_gas_limit(a); }
+	pub fn set_gas_limit(&mut self, a: U256) { self.block.base.header.set_gas_limit(a); }
 
 	/// Alter the gas limit for the block.
-	pub fn set_gas_used(&mut self, a: U256) { self.block.header.set_gas_used(a); }
+	pub fn set_gas_used(&mut self, a: U256) { self.block.base.header.set_gas_used(a); }
 
 	/// 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() {
 			Err(BlockError::ExtraDataOutOfBounds(OutOfBounds{min: None, max: Some(self.engine.maximum_extra_data_size()), found: extra_data.len()}))
 		} else {
-			self.block.header.set_extra_data(extra_data);
+			self.block.base.header.set_extra_data(extra_data);
 			Ok(())
 		}
 	}
@@ -155,12 +201,12 @@ impl<'x, 'y> OpenBlock<'x, 'y> {
 	/// NOTE Will check chain constraints and the uncle number but will NOT check
 	/// that the header itself is actually valid.
 	pub fn push_uncle(&mut self, valid_uncle_header: Header) -> Result<(), BlockError> {
-		if self.block.uncles.len() >= self.engine.maximum_uncle_count() {
-			return Err(BlockError::TooManyUncles(OutOfBounds{min: None, max: Some(self.engine.maximum_uncle_count()), found: self.block.uncles.len()}));
+		if self.block.base.uncles.len() >= self.engine.maximum_uncle_count() {
+			return Err(BlockError::TooManyUncles(OutOfBounds{min: None, max: Some(self.engine.maximum_uncle_count()), found: self.block.base.uncles.len()}));
 		}
 		// TODO: check number
 		// TODO: check not a direct ancestor (use last_hashes for that)
-		self.block.uncles.push(valid_uncle_header);
+		self.block.base.uncles.push(valid_uncle_header);
 		Ok(())
 	}
 
@@ -168,13 +214,13 @@ impl<'x, 'y> OpenBlock<'x, 'y> {
 	pub fn env_info(&self) -> EnvInfo {
 		// TODO: memoise.
 		EnvInfo {
-			number: self.block.header.number,
-			author: self.block.header.author.clone(),
-			timestamp: self.block.header.timestamp,
-			difficulty: self.block.header.difficulty.clone(),
+			number: self.block.base.header.number,
+			author: self.block.base.header.author.clone(),
+			timestamp: self.block.base.header.timestamp,
+			difficulty: self.block.base.header.difficulty.clone(),
 			last_hashes: self.last_hashes.clone(),		// TODO: should be a reference.
-			gas_used: self.block.archive.last().map(|t| t.receipt.gas_used).unwrap_or(U256::from(0)),
-			gas_limit: self.block.header.gas_limit.clone(),
+			gas_used: self.block.receipts.last().map_or(U256::zero(), |r| r.gas_used),
+			gas_limit: self.block.base.header.gas_limit.clone(),
 		}
 	}
 
@@ -186,9 +232,10 @@ impl<'x, 'y> OpenBlock<'x, 'y> {
 //		info!("env_info says gas_used={}", env_info.gas_used);
 		match self.block.state.apply(&env_info, self.engine, &t) {
 			Ok(receipt) => {
-				self.block.archive_set.insert(h.unwrap_or_else(||t.hash()));
-				self.block.archive.push(Entry { transaction: t, receipt: receipt });
-				Ok(&self.block.archive.last().unwrap().receipt)
+				self.block.transactions_set.insert(h.unwrap_or_else(||t.hash()));
+				self.block.base.transactions.push(t);
+				self.block.receipts.push(receipt);
+				Ok(&self.block.receipts.last().unwrap())
 			}
 			Err(x) => Err(From::from(x))
 		}
@@ -198,25 +245,25 @@ impl<'x, 'y> OpenBlock<'x, 'y> {
 	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());
-		let uncle_bytes = s.block.uncles.iter().fold(RlpStream::new_list(s.block.uncles.len()), |mut s, u| {s.append(&u.rlp(Seal::With)); s} ).out();
-		s.block.header.uncles_hash = uncle_bytes.sha3();
-		s.block.header.state_root = s.block.state.root().clone();
-		s.block.header.receipts_root = ordered_trie_root(s.block.archive.iter().map(|ref e| e.receipt.rlp_bytes()).collect());
-		s.block.header.log_bloom = s.block.archive.iter().fold(LogBloom::zero(), |mut b, e| {b |= &e.receipt.log_bloom; b});
-		s.block.header.gas_used = s.block.archive.last().map(|t| t.receipt.gas_used).unwrap_or(U256::from(0));
-		s.block.header.note_dirty();
+		s.block.base.header.transactions_root = ordered_trie_root(s.block.base.transactions.iter().map(|ref e| e.rlp_bytes()).collect());
+		let uncle_bytes = s.block.base.uncles.iter().fold(RlpStream::new_list(s.block.base.uncles.len()), |mut s, u| {s.append(&u.rlp(Seal::With)); s} ).out();
+		s.block.base.header.uncles_hash = uncle_bytes.sha3();
+		s.block.base.header.state_root = s.block.state.root().clone();
+		s.block.base.header.receipts_root = ordered_trie_root(s.block.receipts.iter().map(|ref r| r.rlp_bytes()).collect());
+		s.block.base.header.log_bloom = s.block.receipts.iter().fold(LogBloom::zero(), |mut b, r| {b |= &r.log_bloom; b});
+		s.block.base.header.gas_used = s.block.receipts.last().map_or(U256::zero(), |r| r.gas_used);
+		s.block.base.header.note_dirty();
 
 		ClosedBlock::new(s, uncle_bytes)
 	}
 }
 
 impl<'x, 'y> IsBlock for OpenBlock<'x, 'y> {
-	fn block(&self) -> &Block { &self.block }
+	fn block(&self) -> &ExecutedBlock { &self.block }
 }
 
 impl<'x, 'y> IsBlock for ClosedBlock<'x, 'y> {
-	fn block(&self) -> &Block { &self.open_block.block }
+	fn block(&self) -> &ExecutedBlock { &self.open_block.block }
 }
 
 impl<'x, 'y> ClosedBlock<'x, 'y> {
@@ -238,7 +285,7 @@ impl<'x, 'y> ClosedBlock<'x, 'y> {
 		if seal.len() != s.open_block.engine.seal_fields() {
 			return Err(BlockError::InvalidSealArity(Mismatch{expected: s.open_block.engine.seal_fields(), found: seal.len()}));
 		}
-		s.open_block.block.header.set_seal(seal);
+		s.open_block.block.base.header.set_seal(seal);
 		Ok(SealedBlock { block: s.open_block.block, uncle_bytes: s.uncle_bytes })
 	}
 
@@ -253,9 +300,9 @@ impl SealedBlock {
 	/// Get the RLP-encoding of the block.
 	pub fn rlp_bytes(&self) -> Bytes {
 		let mut block_rlp = RlpStream::new_list(3);
-		self.block.header.stream_rlp(&mut block_rlp, Seal::With);
-		block_rlp.append_list(self.block.archive.len());
-		for e in self.block.archive.iter() { e.transaction.rlp_append(&mut block_rlp); }
+		self.block.base.header.stream_rlp(&mut block_rlp, Seal::With);
+		block_rlp.append_list(self.block.receipts.len());
+		for t in &self.block.base.transactions { t.rlp_append(&mut block_rlp); }
 		block_rlp.append_raw(&self.uncle_bytes, 1);
 		block_rlp.out()
 	}
@@ -265,7 +312,7 @@ impl SealedBlock {
 }
 
 impl IsBlock for SealedBlock {
-	fn block(&self) -> &Block { &self.block }
+	fn block(&self) -> &ExecutedBlock { &self.block }
 }
 
 /// Enact the block given by block header, transactions and uncles

src/block_queue.rs

@@ -1,12 +1,35 @@
+//! A queue of blocks. Sits between network or other I/O and the BlockChain.
+//! Sorts them ready for blockchain insertion.
 use std::thread::{JoinHandle, self};
 use std::sync::atomic::{AtomicBool, Ordering as AtomicOrdering};
 use util::*;
 use verification::*;
 use error::*;
 use engine::Engine;
-use sync::*;
 use views::*;
 use header::*;
+use service::*;
+
+/// Block queue status
+#[derive(Debug)]
+pub struct BlockQueueInfo {
+	/// Indicates that queue is full
+	pub full: bool,
+	/// Number of queued blocks pending verification
+	pub unverified_queue_size: usize,
+	/// Number of verified queued blocks pending import
+	pub verified_queue_size: usize,
+	/// Number of blocks being verified
+	pub verifying_queue_size: usize,
+}
+
+impl BlockQueueInfo {
+	/// The total size of the queues.
+	pub fn total_queue_size(&self) -> usize { self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size }
+
+	/// The size of the unverified and verifying queues.
+	pub fn incomplete_queue_size(&self) -> usize { self.unverified_queue_size + self.verifying_queue_size }
+}
 
 /// A queue of blocks. Sits between network or other I/O and the BlockChain.
 /// Sorts them ready for blockchain insertion.
@@ -17,6 +40,7 @@ pub struct BlockQueue {
 	verifiers: Vec<JoinHandle<()>>,
 	deleting: Arc<AtomicBool>,
 	ready_signal: Arc<QueueSignal>,
+	empty: Arc<Condvar>,
 	processing: HashSet<H256>
 }
 
@@ -61,16 +85,19 @@ impl BlockQueue {
 		let more_to_verify = Arc::new(Condvar::new());
 		let ready_signal = Arc::new(QueueSignal { signalled: AtomicBool::new(false), message_channel: message_channel });
 		let deleting = Arc::new(AtomicBool::new(false));
+		let empty = Arc::new(Condvar::new());
 
 		let mut verifiers: Vec<JoinHandle<()>> = Vec::new();
-		let thread_count = max(::num_cpus::get(), 2) - 1;
-		for _ in 0..thread_count {
+		let thread_count = max(::num_cpus::get(), 3) - 2;
+		for i in 0..thread_count {
 			let verification = verification.clone();
 			let engine = engine.clone();
 			let more_to_verify = more_to_verify.clone();
 			let ready_signal = ready_signal.clone();
+			let empty = empty.clone();
 			let deleting = deleting.clone();
-			verifiers.push(thread::spawn(move || BlockQueue::verify(verification, engine, more_to_verify, ready_signal,  deleting)));
+			verifiers.push(thread::Builder::new().name(format!("Verifier #{}", i)).spawn(move || BlockQueue::verify(verification, engine, more_to_verify, ready_signal, deleting, empty))
+				.expect("Error starting block verification thread"));
 		}
 		BlockQueue {
 			engine: engine,
@@ -80,13 +107,19 @@ impl BlockQueue {
 			verifiers: verifiers,
 			deleting: deleting.clone(),
 			processing: HashSet::new(),
+			empty: empty.clone(),
 		}
 	}
 
-	fn verify(verification: Arc<Mutex<Verification>>, engine: Arc<Box<Engine>>, wait: Arc<Condvar>, ready: Arc<QueueSignal>, deleting: Arc<AtomicBool>) {
+	fn verify(verification: Arc<Mutex<Verification>>, engine: Arc<Box<Engine>>, wait: Arc<Condvar>, ready: Arc<QueueSignal>, deleting: Arc<AtomicBool>, empty: Arc<Condvar>) {
 		while !deleting.load(AtomicOrdering::Relaxed) {
 			{
 				let mut lock = verification.lock().unwrap();
+
+				if lock.unverified.is_empty() && lock.verifying.is_empty() {
+					empty.notify_all();
+				}
+
 				while lock.unverified.is_empty() && !deleting.load(AtomicOrdering::Relaxed) {
 					lock = wait.wait(lock).unwrap();
 				}
@@ -155,36 +188,46 @@ impl BlockQueue {
 		verification.verifying.clear();
 	}
 
+	/// Wait for queue to be empty
+	pub fn flush(&mut self) {
+		let mut verification = self.verification.lock().unwrap();
+		while !verification.unverified.is_empty() || !verification.verifying.is_empty() {
+			verification = self.empty.wait(verification).unwrap();
+		}
+	}
+
 	/// Add a block to the queue.
 	pub fn import_block(&mut self, bytes: Bytes) -> ImportResult {
 		let header = BlockView::new(&bytes).header();
-		if self.processing.contains(&header.hash()) {
+		let h = header.hash();
+		if self.processing.contains(&h) {
 			return Err(ImportError::AlreadyQueued);
 		}
 		{
 			let mut verification = self.verification.lock().unwrap();
-			if verification.bad.contains(&header.hash()) {
+			if verification.bad.contains(&h) {
 				return Err(ImportError::Bad(None));
 			}
 
 			if verification.bad.contains(&header.parent_hash) {
-				verification.bad.insert(header.hash());
+				verification.bad.insert(h.clone());
 				return Err(ImportError::Bad(None));
 			}
 		}
 
 		match verify_block_basic(&header, &bytes, self.engine.deref().deref()) {
 			Ok(()) => {
-				self.processing.insert(header.hash());
+				self.processing.insert(h.clone());
 				self.verification.lock().unwrap().unverified.push_back(UnVerifiedBlock { header: header, bytes: bytes });
 				self.more_to_verify.notify_all();
+				Ok(h)
 			},
 			Err(err) => {
 				warn!(target: "client", "Stage 1 block verification failed for {}\nError: {:?}", BlockView::new(&bytes).header_view().sha3(), err);
-				self.verification.lock().unwrap().bad.insert(header.hash());
+				self.verification.lock().unwrap().bad.insert(h.clone());
+				Err(From::from(err))
 			}
 		}
-		Ok(())
 	}
 
 	/// Mark given block and all its children as bad. Stops verification.
@@ -204,7 +247,7 @@ impl BlockQueue {
 		verification.verified = new_verified;
 	}
 
-	/// TODO [arkpar] Please document me
+	/// Removes up to `max` verified blocks from the queue
 	pub fn drain(&mut self, max: usize) -> Vec<PreVerifiedBlock> {
 		let mut verification = self.verification.lock().unwrap();
 		let count = min(max, verification.verified.len());
@@ -215,8 +258,22 @@ impl BlockQueue {
 			result.push(block);
 		}
 		self.ready_signal.reset();
+		if !verification.verified.is_empty() {
+			self.ready_signal.set();
+		}
 		result
 	}
+
+	/// Get queue status.
+	pub fn queue_info(&self) -> BlockQueueInfo {
+		let verification = self.verification.lock().unwrap();
+		BlockQueueInfo {
+			full: false,
+			verified_queue_size: verification.verified.len(),
+			unverified_queue_size: verification.unverified.len(),
+			verifying_queue_size: verification.verifying.len(),
+		}
+	}
 }
 
 impl Drop for BlockQueue {
@@ -234,7 +291,7 @@ impl Drop for BlockQueue {
 mod tests {
 	use util::*;
 	use spec::*;
-	use queue::*;
+	use block_queue::*;
 
 	#[test]
 	fn test_block_queue() {

src/blockchain.rs

@@ -107,6 +107,11 @@ pub trait BlockProvider {
 	fn genesis_hash(&self) -> H256 {
 		self.block_hash(0).expect("Genesis hash should always exist")
 	}
+
+	/// Returns the header of the genesis block.
+	fn genesis_header(&self) -> Header {
+		self.block_header(&self.genesis_hash()).unwrap()
+	}
 }
 
 #[derive(Debug, Hash, Eq, PartialEq, Clone)]
@@ -153,9 +158,8 @@ impl BlockProvider for BlockChain {
 	fn block(&self, hash: &H256) -> Option<Bytes> {
 		{
 			let read = self.blocks.read().unwrap();
-			match read.get(hash) {
-				Some(v) => return Some(v.clone()),
-				None => ()
+			if let Some(v) = read.get(hash) {
+				return Some(v.clone());
 			}
 		}
 
@@ -188,7 +192,7 @@ impl BlockProvider for BlockChain {
 
 const COLLECTION_QUEUE_SIZE: usize = 2;
 const MIN_CACHE_SIZE: usize = 1;
-const MAX_CACHE_SIZE: usize = 1024 * 1024 * 1;
+const MAX_CACHE_SIZE: usize = 1024 * 1024;
 
 impl BlockChain {
 	/// Create new instance of blockchain from given Genesis
@@ -284,13 +288,6 @@ impl BlockChain {
 		bc
 	}
 
-	/// Ensure that the best block does indeed have a state_root in the state DB.
-	/// If it doesn't, then rewind down until we find one that does and delete data to ensure that
-	/// later blocks will be reimported. 
-	pub fn ensure_good(&mut self, _state: &JournalDB) {
-		unimplemented!();
-	}
-
 	/// Returns a tree route between `from` and `to`, which is a tuple of:
 	///
 	/// - a vector of hashes of all blocks, ordered from `from` to `to`.
@@ -342,19 +339,19 @@ impl BlockChain {
 			Some(h) => h,
 			None => return None,
 		};
-		Some(self._tree_route((from_details, from), (to_details, to)))
+		Some(self._tree_route((&from_details, &from), (&to_details, &to)))
 	}
 
 	/// Similar to `tree_route` function, but can be used to return a route
 	/// between blocks which may not be in database yet.
-	fn _tree_route(&self, from: (BlockDetails, H256), to: (BlockDetails, H256)) -> TreeRoute {
+	fn _tree_route(&self, from: (&BlockDetails, &H256), to: (&BlockDetails, &H256)) -> TreeRoute {
 		let mut from_branch = vec![];
 		let mut to_branch = vec![];
 
-		let mut from_details = from.0;
-		let mut to_details = to.0;
-		let mut current_from = from.1;
-		let mut current_to = to.1;
+		let mut from_details = from.0.clone();
+		let mut to_details = to.0.clone();
+		let mut current_from = from.1.clone();
+		let mut current_to = to.1.clone();
 
 		// reset from && to to the same level
 		while from_details.number > to_details.number {
@@ -393,7 +390,6 @@ impl BlockChain {
 		}
 	}
 
-
 	/// Inserts the block into backing cache database.
 	/// Expects the block to be valid and already verified.
 	/// If the block is already known, does nothing.
@@ -409,7 +405,7 @@ impl BlockChain {
 
 		// store block in db
 		self.blocks_db.put(&hash, &bytes).unwrap();
-		let (batch, new_best) = self.block_to_extras_insert_batch(bytes);
+		let (batch, new_best, details) = self.block_to_extras_insert_batch(bytes);
 
 		// update best block
 		let mut best_block = self.best_block.write().unwrap();
@@ -420,6 +416,8 @@ impl BlockChain {
 		// update caches
 		let mut write = self.block_details.write().unwrap();
 		write.remove(&header.parent_hash());
+		write.insert(hash.clone(), details);
+		self.note_used(CacheID::Block(hash));
 
 		// update extras database
 		self.extras_db.write(batch).unwrap();
@@ -427,7 +425,7 @@ impl BlockChain {
 
 	/// Transforms block into WriteBatch that may be written into database
 	/// Additionally, if it's new best block it returns new best block object.
-	fn block_to_extras_insert_batch(&self, bytes: &[u8]) -> (WriteBatch, Option<BestBlock>) {
+	fn block_to_extras_insert_batch(&self, bytes: &[u8]) -> (WriteBatch, Option<BestBlock>, BlockDetails) {
 		// create views onto rlp
 		let block = BlockView::new(bytes);
 		let header = block.header_view();
@@ -459,7 +457,7 @@ impl BlockChain {
 
 		// if it's not new best block, just return
 		if !is_new_best {
-			return (batch, None);
+			return (batch, None, details);
 		}
 
 		// if its new best block we need to make sure that all ancestors
@@ -467,7 +465,7 @@ impl BlockChain {
 		// find the route between old best block and the new one
 		let best_hash = self.best_block_hash();
 		let best_details = self.block_details(&best_hash).expect("best block hash is invalid!");
-		let route = self._tree_route((best_details, best_hash), (details, hash.clone()));
+		let route = self._tree_route((&best_details, &best_hash), (&details, &hash));
 
 		match route.blocks.len() {
 			// its our parent
@@ -494,7 +492,7 @@ impl BlockChain {
 			total_difficulty: total_difficulty
 		};
 
-		(batch, Some(best_block))
+		(batch, Some(best_block), details)
 	}
 
 	/// Returns true if transaction is known.
@@ -527,9 +525,8 @@ impl BlockChain {
 		K: ExtrasSliceConvertable + Eq + Hash + Clone {
 		{
 			let read = cache.read().unwrap();
-			match read.get(hash) {
-				Some(v) => return Some(v.clone()),
-				None => ()
+			if let Some(v) = read.get(hash) {
+				return Some(v.clone());
 			}
 		}
 
@@ -549,9 +546,8 @@ impl BlockChain {
 		T: ExtrasIndexable {
 		{
 			let read = cache.read().unwrap();
-			match read.get(hash) {
-				Some(_) => return true,
-				None => ()
+			if let Some(_) = read.get(hash) {
+				return true;
 			}
 		}
 
@@ -569,15 +565,6 @@ impl BlockChain {
 		}
 	}
 
-	/// Tries to squeeze the cache if its too big.
-	pub fn squeeze_to_fit(&self, size: CacheSize) {
-		self.blocks.write().unwrap().squeeze(size.blocks);
-		self.block_details.write().unwrap().squeeze(size.block_details);
-		self.transaction_addresses.write().unwrap().squeeze(size.transaction_addresses);
-		self.block_logs.write().unwrap().squeeze(size.block_logs);
-		self.blocks_blooms.write().unwrap().squeeze(size.blocks_blooms);
-	}
-
 	/// Let the cache system know that a cacheable item has been used.
 	fn note_used(&self, id: CacheID) {
 		let mut cache_man = self.cache_man.write().unwrap();
@@ -631,20 +618,18 @@ impl BlockChain {
 
 #[cfg(test)]
 mod tests {
-	use std::env;
 	use std::str::FromStr;
 	use rustc_serialize::hex::FromHex;
 	use util::hash::*;
 	use blockchain::*;
+	use tests::helpers::*;
 
 	#[test]
 	fn valid_tests_extra32() {
 		let genesis = "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".from_hex().unwrap();
 
-		let mut dir = env::temp_dir();
-		dir.push(H32::random().hex());
-
-		let bc = BlockChain::new(&genesis, &dir);
+		let temp = RandomTempPath::new();
+		let bc = BlockChain::new(&genesis, temp.as_path());
 
 		let genesis_hash = H256::from_str("3caa2203f3d7c136c0295ed128a7d31cea520b1ca5e27afe17d0853331798942").unwrap();
 
@@ -670,6 +655,7 @@ mod tests {
 	}
 
 	#[test]
+	#[allow(cyclomatic_complexity)]
 	fn test_small_fork() {
 		let genesis = "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".from_hex().unwrap();
 		let b1 = "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".from_hex().unwrap();
@@ -686,10 +672,8 @@ mod tests {
 		// b3a is a part of canon chain, whereas b3b is part of sidechain
 		let best_block_hash = H256::from_str("c208f88c9f5bf7e00840439742c12e5226d9752981f3ec0521bdcb6dd08af277").unwrap();
 
-		let mut dir = env::temp_dir();
-		dir.push(H32::random().hex());
-
-		let bc = BlockChain::new(&genesis, &dir);
+		let temp = RandomTempPath::new();
+		let bc = BlockChain::new(&genesis, temp.as_path());
 		bc.insert_block(&b1);
 		bc.insert_block(&b2);
 		bc.insert_block(&b3a);
@@ -766,18 +750,16 @@ mod tests {
 		let genesis_hash = H256::from_str("5716670833ec874362d65fea27a7cd35af5897d275b31a44944113111e4e96d2").unwrap();
 		let b1_hash = H256::from_str("437e51676ff10756fcfee5edd9159fa41dbcb1b2c592850450371cbecd54ee4f").unwrap();
 
-		let mut dir = env::temp_dir();
-		dir.push(H32::random().hex());
-
+		let temp = RandomTempPath::new();
 		{
-			let bc = BlockChain::new(&genesis, &dir);
+			let bc = BlockChain::new(&genesis, temp.as_path());
 			assert_eq!(bc.best_block_hash(), genesis_hash);
 			bc.insert_block(&b1);
 			assert_eq!(bc.best_block_hash(), b1_hash);
 		}
 
 		{
-			let bc = BlockChain::new(&genesis, &dir);
+			let bc = BlockChain::new(&genesis, temp.as_path());
 			assert_eq!(bc.best_block_hash(), b1_hash);
 		}
 	}

src/builtin.rs

@@ -94,16 +94,13 @@ pub fn new_builtin_exec(name: &str) -> Option<Box<Fn(&[u8], &mut [u8])>> {
 			if it.v == H256::from(&U256::from(27)) || it.v == H256::from(&U256::from(28)) {
 				let s = Signature::from_rsv(&it.r, &it.s, it.v[31] - 27);
 				if ec::is_valid(&s) {
-					match ec::recover(&s, &it.hash) {
-						Ok(p) => {
-							let r = p.as_slice().sha3();
-							// NICE: optimise and separate out into populate-like function
-							for i in 0..min(32, output.len()) {
-								output[i] = if i < 12 {0} else {r[i]};
-							}
+					if let Ok(p) = ec::recover(&s, &it.hash) {
+						let r = p.as_slice().sha3();
+						// NICE: optimise and separate out into populate-like function
+						for i in 0..min(32, output.len()) {
+							output[i] = if i < 12 {0} else {r[i]};
 						}
-						_ => {}
-					};
+					}
 				}
 			}
 		})),

src/client.rs

@@ -4,10 +4,12 @@ use blockchain::{BlockChain, BlockProvider, CacheSize};
 use views::BlockView;
 use error::*;
 use header::BlockNumber;
+use state::State;
 use spec::Spec;
 use engine::Engine;
-use queue::BlockQueue;
-use sync::NetSyncMessage;
+use views::HeaderView;
+use block_queue::{BlockQueue, BlockQueueInfo};
+use service::NetSyncMessage;
 use env_info::LastHashes;
 use verification::*;
 use block::*;
@@ -46,13 +48,6 @@ impl fmt::Display for BlockChainInfo {
 	}
 }
 
-/// Block queue status
-#[derive(Debug)]
-pub struct BlockQueueStatus {
-	/// TODO [arkpar] Please document me
-	pub full: bool,
-}
-
 /// TODO [arkpar] Please document me
 pub type TreeRoute = ::blockchain::TreeRoute;
 
@@ -71,6 +66,9 @@ pub trait BlockChainClient : Sync + Send {
 	/// Get block status by block header hash.
 	fn block_status(&self, hash: &H256) -> BlockStatus;
 
+	/// Get block total difficulty.
+	fn block_total_difficulty(&self, hash: &H256) -> Option<U256>;
+
 	/// Get raw block header data by block number.
 	fn block_header_at(&self, n: BlockNumber) -> Option<Bytes>;
 
@@ -84,6 +82,9 @@ pub trait BlockChainClient : Sync + Send {
 	/// Get block status by block number.
 	fn block_status_at(&self, n: BlockNumber) -> BlockStatus;
 
+	/// Get block total difficulty.
+	fn block_total_difficulty_at(&self, n: BlockNumber) -> Option<U256>;
+
 	/// Get a tree route between `from` and `to`.
 	/// See `BlockChain::tree_route`.
 	fn tree_route(&self, from: &H256, to: &H256) -> Option<TreeRoute>;
@@ -95,16 +96,21 @@ pub trait BlockChainClient : Sync + Send {
 	fn block_receipts(&self, hash: &H256) -> Option<Bytes>;
 
 	/// Import a block into the blockchain.
-	fn import_block(&mut self, bytes: Bytes) -> ImportResult;
+	fn import_block(&self, bytes: Bytes) -> ImportResult;
 
 	/// Get block queue information.
-	fn queue_status(&self) -> BlockQueueStatus;
+	fn queue_info(&self) -> BlockQueueInfo;
 
 	/// Clear block queue and abort all import activity.
-	fn clear_queue(&mut self);
+	fn clear_queue(&self);
 
 	/// Get blockchain information.
 	fn chain_info(&self) -> BlockChainInfo;
+
+	/// Get the best block header.
+	fn best_block_header(&self) -> Bytes {
+		self.block_header(&self.chain_info().best_block_hash).unwrap()
+	}
 }
 
 #[derive(Default, Clone, Debug, Eq, PartialEq)]
@@ -128,24 +134,29 @@ impl ClientReport {
 }
 
 /// Blockchain database client backed by a persistent database. Owns and manages a blockchain and a block queue.
+/// Call `import_block()` to import a block asynchronously; `flush_queue()` flushes the queue.
 pub struct Client {
 	chain: Arc<RwLock<BlockChain>>,
 	engine: Arc<Box<Engine>>,
 	state_db: JournalDB,
-	queue: BlockQueue,
-	report: ClientReport,
+	block_queue: RwLock<BlockQueue>,
+	report: RwLock<ClientReport>,
+	uncommited_states: RwLock<HashMap<H256, JournalDB>>,
+	import_lock: Mutex<()>
 }
 
 const HISTORY: u64 = 1000;
 
 impl Client {
 	/// Create a new client with given spec and DB path.
-	pub fn new(spec: Spec, path: &Path, message_channel: IoChannel<NetSyncMessage> ) -> Result<Client, Error> {
-		let chain = Arc::new(RwLock::new(BlockChain::new(&spec.genesis_block(), path)));
+	pub fn new(spec: Spec, path: &Path, message_channel: IoChannel<NetSyncMessage> ) -> Result<Arc<Client>, Error> {
+		let gb = spec.genesis_block();
+		let chain = Arc::new(RwLock::new(BlockChain::new(&gb, path)));
 		let mut opts = Options::new();
-		opts.create_if_missing(true);
 		opts.set_max_open_files(256);
-		/*opts.set_use_fsync(false);
+		opts.create_if_missing(true);
+		opts.set_use_fsync(false);
+		/*
 		opts.set_bytes_per_sync(8388608);
 		opts.set_disable_data_sync(false);
 		opts.set_block_cache_size_mb(1024);
@@ -164,37 +175,38 @@ impl Client {
 
 		let mut state_path = path.to_path_buf();
 		state_path.push("state");
-		let db = DB::open(&opts, state_path.to_str().unwrap()).unwrap();
-		let mut state_db = JournalDB::new(db);
+		let db = Arc::new(DB::open(&opts, state_path.to_str().unwrap()).unwrap());
 		
 		let engine = Arc::new(try!(spec.to_engine()));
+		let mut state_db = JournalDB::new_with_arc(db.clone());
 		if engine.spec().ensure_db_good(&mut state_db) {
 			state_db.commit(0, &engine.spec().genesis_header().hash(), None).expect("Error commiting genesis state to state DB");
 		}
-
-//		chain.write().unwrap().ensure_good(&state_db);
-
-		Ok(Client {
+		Ok(Arc::new(Client {
 			chain: chain,
 			engine: engine.clone(),
 			state_db: state_db,
-			queue: BlockQueue::new(engine, message_channel),
-			report: Default::default(),
-		})
+			block_queue: RwLock::new(BlockQueue::new(engine, message_channel)),
+			report: RwLock::new(Default::default()),
+			uncommited_states: RwLock::new(HashMap::new()),
+			import_lock: Mutex::new(()),
+		}))
+	}
+
+	/// Flush the block import queue.
+	pub fn flush_queue(&self) {
+		self.block_queue.write().unwrap().flush();
 	}
 
 	/// This is triggered by a message coming from a block queue when the block is ready for insertion
-	pub fn import_verified_blocks(&mut self) {
-		
+	pub fn import_verified_blocks(&self, _io: &IoChannel<NetSyncMessage>) -> usize {
+		let mut ret = 0;
 		let mut bad = HashSet::new();
-		let blocks = self.queue.drain(128); 
-		if blocks.is_empty() {
-			return;
-		}
-
+		let _import_lock = self.import_lock.lock();
+		let blocks = self.block_queue.write().unwrap().drain(128);
 		for block in blocks {
 			if bad.contains(&block.header.parent_hash) {
-				self.queue.mark_as_bad(&block.header.hash());
+				self.block_queue.write().unwrap().mark_as_bad(&block.header.hash());
 				bad.insert(block.header.hash());
 				continue;
 			}
@@ -202,17 +214,17 @@ impl Client {
 			let header = &block.header;
 			if let Err(e) = verify_block_family(&header, &block.bytes, self.engine.deref().deref(), self.chain.read().unwrap().deref()) {
 				warn!(target: "client", "Stage 3 block verification failed for #{} ({})\nError: {:?}", header.number(), header.hash(), e);
-				self.queue.mark_as_bad(&header.hash());
+				self.block_queue.write().unwrap().mark_as_bad(&header.hash());
 				bad.insert(block.header.hash());
-				return;
+				break;
 			};
 			let parent = match self.chain.read().unwrap().block_header(&header.parent_hash) {
 				Some(p) => p,
 				None => {
 					warn!(target: "client", "Block import failed for #{} ({}): Parent not found ({}) ", header.number(), header.hash(), header.parent_hash);
-					self.queue.mark_as_bad(&header.hash());
+					self.block_queue.write().unwrap().mark_as_bad(&header.hash());
 					bad.insert(block.header.hash());
-					return;
+					break;
 				},
 			};
 			// build last hashes
@@ -228,19 +240,20 @@ impl Client {
 				}
 			}
 
-			let result = match enact_verified(&block, self.engine.deref().deref(), self.state_db.clone(), &parent, &last_hashes) {
+			let db = self.state_db.clone();
+			let result = match enact_verified(&block, self.engine.deref().deref(), db, &parent, &last_hashes) {
 				Ok(b) => b,
 				Err(e) => {
 					warn!(target: "client", "Block import failed for #{} ({})\nError: {:?}", header.number(), header.hash(), e);
-				bad.insert(block.header.hash());
-					self.queue.mark_as_bad(&header.hash());
-					return;
+					bad.insert(block.header.hash());
+					self.block_queue.write().unwrap().mark_as_bad(&header.hash());
+					break;
 				}
 			};
 			if let Err(e) = verify_block_final(&header, result.block().header()) {
 				warn!(target: "client", "Stage 4 block verification failed for #{} ({})\nError: {:?}", header.number(), header.hash(), e);
-				self.queue.mark_as_bad(&header.hash());
-				return;
+				self.block_queue.write().unwrap().mark_as_bad(&header.hash());
+				break;
 			}
 
 			self.chain.write().unwrap().insert_block(&block.bytes); //TODO: err here?
@@ -249,13 +262,24 @@ impl Client {
 				Ok(_) => (),
 				Err(e) => {
 					warn!(target: "client", "State DB commit failed: {:?}", e);
-					return;
+					break;
 				}
 			}
-			self.report.accrue_block(&block);
-
+			self.report.write().unwrap().accrue_block(&block);
 			trace!(target: "client", "Imported #{} ({})", header.number(), header.hash());
+			ret += 1;
 		}
+		ret
+	}
+
+	/// Clear cached state overlay 
+	pub fn clear_state(&self, hash: &H256) {
+		self.uncommited_states.write().unwrap().remove(hash);
+	}
+
+	/// Get a copy of the best block's state.
+	pub fn state(&self) -> State {
+		State::from_existing(self.state_db.clone(), HeaderView::new(&self.best_block_header()).state_root(), self.engine.account_start_nonce())
 	}
 
 	/// Get info on the cache.
@@ -265,7 +289,7 @@ impl Client {
 
 	/// Get the report.
 	pub fn report(&self) -> ClientReport {
-		self.report.clone()
+		self.report.read().unwrap().clone()
 	}
 
 	/// Tick the client.
@@ -296,6 +320,10 @@ impl BlockChainClient for Client {
 	fn block_status(&self, hash: &H256) -> BlockStatus {
 		if self.chain.read().unwrap().is_known(&hash) { BlockStatus::InChain } else { BlockStatus::Unknown }
 	}
+	
+	fn block_total_difficulty(&self, hash: &H256) -> Option<U256> {
+		self.chain.read().unwrap().block_details(hash).map(|d| d.total_difficulty)
+	}
 
 	fn block_header_at(&self, n: BlockNumber) -> Option<Bytes> {
 		self.chain.read().unwrap().block_hash(n).and_then(|h| self.block_header(&h))
@@ -316,6 +344,10 @@ impl BlockChainClient for Client {
 		}
 	}
 
+	fn block_total_difficulty_at(&self, n: BlockNumber) -> Option<U256> {
+		self.chain.read().unwrap().block_hash(n).and_then(|h| self.block_total_difficulty(&h))
+	}
+
 	fn tree_route(&self, from: &H256, to: &H256) -> Option<TreeRoute> {
 		self.chain.read().unwrap().tree_route(from.clone(), to.clone())
 	}
@@ -328,21 +360,20 @@ impl BlockChainClient for Client {
 		unimplemented!();
 	}
 
-	fn import_block(&mut self, bytes: Bytes) -> ImportResult {
+	fn import_block(&self, bytes: Bytes) -> ImportResult {
 		let header = BlockView::new(&bytes).header();
 		if self.chain.read().unwrap().is_known(&header.hash()) {
 			return Err(ImportError::AlreadyInChain);
 		}
-		self.queue.import_block(bytes)
+		self.block_queue.write().unwrap().import_block(bytes)
 	}
 
-	fn queue_status(&self) -> BlockQueueStatus {
-		BlockQueueStatus {
-			full: false
-		}
+	fn queue_info(&self) -> BlockQueueInfo {
+		self.block_queue.read().unwrap().queue_info()
 	}
 
-	fn clear_queue(&mut self) {
+	fn clear_queue(&self) {
+		self.block_queue.write().unwrap().clear();
 	}
 
 	fn chain_info(&self) -> BlockChainInfo {

src/engine.rs

@@ -1,5 +1,5 @@
 use common::*;
-use block::Block;
+use block::ExecutedBlock;
 use spec::Spec;
 use evm::Schedule;
 use evm::Factory;
@@ -37,9 +37,9 @@ pub trait Engine : Sync + Send {
 	fn account_start_nonce(&self) -> U256 { decode(&self.spec().engine_params.get("accountStartNonce").unwrap()) }
 
 	/// Block transformation functions, before and after the transactions.
-	fn on_new_block(&self, _block: &mut Block) {}
+	fn on_new_block(&self, _block: &mut ExecutedBlock) {}
 	/// TODO [Gav Wood] Please document me
-	fn on_close_block(&self, _block: &mut Block) {}
+	fn on_close_block(&self, _block: &mut ExecutedBlock) {}
 
 	// TODO: consider including State in the params for verification functions.
 	/// Phase 1 quick block verification. Only does checks that are cheap. `block` (the header's full block) 

src/env_info.rs

@@ -25,8 +25,14 @@ pub struct EnvInfo {
 }
 
 impl EnvInfo {
-	/// TODO [debris] Please document me
+	/// Create empty env_info initialized with zeros
 	pub fn new() -> EnvInfo {
+		EnvInfo::default()
+	}
+}
+
+impl Default for EnvInfo {
+	fn default() -> Self {
 		EnvInfo {
 			number: 0,
 			author: Address::new(),
@@ -53,11 +59,3 @@ impl FromJson for EnvInfo {
 		}
 	}
 }
-
-/// TODO: it should be the other way around.
-/// `new` should call `default`.
-impl Default for EnvInfo {
-	fn default() -> Self {
-		EnvInfo::new()
-	}
-}

src/error.rs

@@ -120,7 +120,9 @@ pub enum BlockError {
 	/// TODO [arkpar] Please document me
 	InvalidParentHash(Mismatch<H256>),
 	/// TODO [arkpar] Please document me
-	InvalidNumber(OutOfBounds<BlockNumber>),
+	InvalidNumber(Mismatch<BlockNumber>),
+	/// Block number isn't sensible.
+	RidiculousNumber(OutOfBounds<BlockNumber>),
 	/// TODO [arkpar] Please document me
 	UnknownParent(H256),
 	/// TODO [Gav Wood] Please document me
@@ -145,7 +147,7 @@ impl From<Error> for ImportError {
 }
 
 /// Result of import block operation.
-pub type ImportResult = Result<(), ImportError>;
+pub type ImportResult = Result<H256, ImportError>;
 
 #[derive(Debug)]
 /// General error type which should be capable of representing all errors in ethcore.

src/ethereum/ethash.rs

@@ -32,13 +32,13 @@ impl Ethash {
 	}
 
 	fn u64_param(&self, name: &str) -> u64 {
-		*self.u64_params.write().unwrap().entry(name.to_string()).or_insert_with(||
-			self.spec().engine_params.get(name).map(|a| decode(&a)).unwrap_or(0u64))
+		*self.u64_params.write().unwrap().entry(name.to_owned()).or_insert_with(||
+			self.spec().engine_params.get(name).map_or(0u64, |a| decode(&a)))
 	}
 
 	fn u256_param(&self, name: &str) -> U256 {
-		*self.u256_params.write().unwrap().entry(name.to_string()).or_insert_with(||
-			self.spec().engine_params.get(name).map(|a| decode(&a)).unwrap_or(x!(0)))
+		*self.u256_params.write().unwrap().entry(name.to_owned()).or_insert_with(||
+			self.spec().engine_params.get(name).map_or(x!(0), |a| decode(&a)))
 	}
 }
 
@@ -83,8 +83,8 @@ impl Engine for Ethash {
 
 	/// 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 reward = self.spec().engine_params.get("blockReward").map(|a| decode(&a)).unwrap_or(U256::from(0u64));
+	fn on_close_block(&self, block: &mut ExecutedBlock) {
+		let reward = self.spec().engine_params.get("blockReward").map_or(U256::from(0u64), |a| decode(&a));
 		let fields = block.fields();
 
 		// Bestow block reward
@@ -99,13 +99,17 @@ impl Engine for Ethash {
 	}
 
 	fn verify_block_basic(&self, header: &Header, _block: Option<&[u8]>) -> result::Result<(), Error> {
+		// check the seal fields.
+		try!(UntrustedRlp::new(&header.seal[0]).as_val::<H256>());
+		try!(UntrustedRlp::new(&header.seal[1]).as_val::<H64>());
+
 		let min_difficulty = decode(self.spec().engine_params.get("minimumDifficulty").unwrap());
 		if header.difficulty < min_difficulty {
 			return Err(From::from(BlockError::InvalidDifficulty(Mismatch { expected: min_difficulty, found: header.difficulty })))
 		}
 		let difficulty = Ethash::boundary_to_difficulty(&Ethash::from_ethash(quick_get_difficulty(
 				&Ethash::to_ethash(header.bare_hash()), 
-				header.nonce(),
+				header.nonce().low_u64(),
 				&Ethash::to_ethash(header.mix_hash()))));
 		if difficulty < header.difficulty {
 			return Err(From::from(BlockError::InvalidEthashDifficulty(Mismatch { expected: header.difficulty, found: difficulty })));
@@ -114,7 +118,7 @@ impl Engine for Ethash {
 	}
 
 	fn verify_block_unordered(&self, header: &Header, _block: Option<&[u8]>) -> result::Result<(), Error> {
-		let result = self.pow.compute_light(header.number as u64, &Ethash::to_ethash(header.bare_hash()), header.nonce());
+		let result = self.pow.compute_light(header.number as u64, &Ethash::to_ethash(header.bare_hash()), header.nonce().low_u64());
 		let mix = Ethash::from_ethash(result.mix_hash);
 		let difficulty = Ethash::boundary_to_difficulty(&Ethash::from_ethash(result.value));
 		if mix != header.mix_hash() {
@@ -153,6 +157,7 @@ impl Engine for Ethash {
 	}
 }
 
+#[allow(wrong_self_convention)] // to_ethash should take self
 impl Ethash {
 	fn calculate_difficuty(&self, header: &Header, parent: &Header) -> U256 {
 		const EXP_DIFF_PERIOD: u64 = 100000;
@@ -203,7 +208,7 @@ impl Ethash {
 }
 
 impl Header {
-	fn nonce(&self) -> u64 {
+	fn nonce(&self) -> H64 {
 		decode(&self.seal()[1])
 	}
 	fn mix_hash(&self) -> H256 {

src/evm/ext.rs

@@ -26,7 +26,7 @@ pub enum MessageCallResult {
 	Failed
 }
 
-/// TODO [debris] Please document me
+/// Externalities interface for EVMs
 pub trait Ext {
 	/// Returns a value for given key.
 	fn storage_at(&self, key: &H256) -> H256;
@@ -55,8 +55,9 @@ pub trait Ext {
 	/// and true if subcall was successfull.
 	fn call(&mut self, 
 			gas: &U256, 
-			address: &Address, 
-			value: &U256, 
+			sender_address: &Address, 
+			receive_address: &Address, 
+			value: Option<U256>,
 			data: &[u8], 
 			code_address: &Address, 
 			output: &mut [u8]) -> MessageCallResult;

src/evm/factory.rs

@@ -68,10 +68,11 @@ impl Factory {
 	fn jit() -> Box<Evm> {
 		unimplemented!()
 	}
-
+}
+impl Default for Factory {
 	/// Returns jitvm factory
 	#[cfg(feature = "jit")]
-	pub fn default() -> Factory {
+	fn default() -> Factory {
 		Factory {
 			evm: VMType::Jit
 		}
@@ -79,7 +80,7 @@ impl Factory {
 
 	/// Returns native rust evm factory
 	#[cfg(not(feature = "jit"))]
-	pub fn default() -> Factory {
+	fn default() -> Factory {
 		Factory {
 			evm: VMType::Interpreter
 		}

src/evm/interpreter.rs

@@ -7,19 +7,19 @@ use super::instructions::Instruction;
 use std::marker::Copy;
 use evm::{MessageCallResult, ContractCreateResult};
 
-#[cfg(not(feature = "evm_debug"))]
+#[cfg(not(feature = "evm-debug"))]
 macro_rules! evm_debug {
 	($x: expr) => {}
 }
 
-#[cfg(feature = "evm_debug")]
+#[cfg(feature = "evm-debug")]
 macro_rules! evm_debug {
 	($x: expr) => {
 		$x
 	}
 }
 
-#[cfg(feature = "evm_debug")]
+#[cfg(feature = "evm-debug")]
 fn color(instruction: Instruction, name: &'static str) -> String {
 	let c = instruction as usize % 6;
 	let colors = [31, 34, 33, 32, 35, 36];
@@ -72,7 +72,7 @@ impl<S : Copy> VecStack<S> {
 
 impl<S : fmt::Display> Stack<S> for VecStack<S> {
 	fn peek(&self, no_from_top: usize) -> &S {
-		return &self.stack[self.stack.len() - no_from_top - 1];
+		&self.stack[self.stack.len() - no_from_top - 1]
 	}
 
 	fn swap_with_top(&mut self, no_from_top: usize) {
@@ -157,7 +157,7 @@ impl Memory for Vec<u8> {
 	}
 
 	fn size(&self) -> usize {
-		return self.len()
+		self.len()
 	}
 
 	fn read_slice(&self, init_off_u: U256, init_size_u: U256) -> &[u8] {
@@ -228,6 +228,7 @@ struct CodeReader<'a> {
 	code: &'a Bytes
 }
 
+#[allow(len_without_is_empty)]
 impl<'a> CodeReader<'a> {
 	/// Get `no_of_bytes` from code and convert to U256. Move PC
 	fn read(&mut self, no_of_bytes: usize) -> U256 {
@@ -330,6 +331,7 @@ impl evm::Evm for Interpreter {
 }
 
 impl Interpreter {
+	#[allow(cyclomatic_complexity)]
 	fn get_gas_cost_mem(&self,
 						ext: &evm::Ext,
 						instruction: Instruction,
@@ -569,16 +571,10 @@ impl Interpreter {
 				let call_gas = stack.pop_back();
 				let code_address = stack.pop_back();
 				let code_address = u256_to_address(&code_address);
-				let is_delegatecall = instruction == instructions::DELEGATECALL;
 
-				let value = match is_delegatecall {
-					true => params.value,
-					false => stack.pop_back()
-				};
-
-				let address = match instruction == instructions::CALL {
-					true => &code_address,
-					false => &params.address
+				let value = match instruction == instructions::DELEGATECALL {
+					true => None,
+					false => Some(stack.pop_back())
 				};
 
 				let in_off = stack.pop_back();
@@ -586,13 +582,27 @@ impl Interpreter {
 				let out_off = stack.pop_back();
 				let out_size = stack.pop_back();
 
-				let call_gas = call_gas + match !is_delegatecall && value > U256::zero() {
+				// Add stipend (only CALL|CALLCODE when value > 0)
+				let call_gas = call_gas + value.map_or_else(U256::zero, |val| match val > U256::zero() {
 					true => U256::from(ext.schedule().call_stipend),
 					false => U256::zero()
+				});
+
+				// Get sender & receive addresses, check if we have balance
+				let (sender_address, receive_address, has_balance) = match instruction {
+					instructions::CALL => {
+						let has_balance = ext.balance(&params.address) >= value.unwrap();
+						(&params.address, &code_address, has_balance)
+					},
+					instructions::CALLCODE => {
+						let has_balance = ext.balance(&params.address) >= value.unwrap();
+						(&params.address, &params.address, has_balance)
+					},
+					instructions::DELEGATECALL => (&params.sender, &params.address, true),
+					_ => panic!(format!("Unexpected instruction {} in CALL branch.", instruction))
 				};
 
-				let can_call = (is_delegatecall || ext.balance(&params.address) >= value) && ext.depth() < ext.schedule().max_depth;
-
+				let can_call = has_balance && ext.depth() < ext.schedule().max_depth;
 				if !can_call {
 					stack.push(U256::zero());
 					return Ok(InstructionResult::UnusedGas(call_gas));
@@ -603,7 +613,7 @@ impl Interpreter {
 					// and we don't want to copy
 					let input = unsafe { ::std::mem::transmute(mem.read_slice(in_off, in_size)) };
 					let output = mem.writeable_slice(out_off, out_size);
-					ext.call(&call_gas, address, &value, input, &code_address, output)
+					ext.call(&call_gas, sender_address, receive_address, value, input, &code_address, output)
 				};
 
 				return match call_result {
@@ -710,13 +720,16 @@ impl Interpreter {
 				stack.push(address_to_u256(params.sender.clone()));
 			},
 			instructions::CALLVALUE => {
-				stack.push(params.value.clone());
+				stack.push(match params.value {
+					ActionValue::Transfer(val) => val,
+					ActionValue::Apparent(val) => val,
+				});
 			},
 			instructions::CALLDATALOAD => {
 				let big_id = stack.pop_back();
 				let id = big_id.low_u64() as usize;
 				let max = id.wrapping_add(32);
-				let data = params.data.clone().unwrap_or(vec![]);
+				let data = params.data.clone().unwrap_or_else(|| vec![]);
 				let bound = cmp::min(data.len(), max);
 				if id < bound && big_id < U256::from(data.len()) {
 					let mut v = data[id..bound].to_vec();
@@ -727,7 +740,7 @@ impl Interpreter {
 				}
 			},
 			instructions::CALLDATASIZE => {
-				stack.push(U256::from(params.data.clone().unwrap_or(vec![]).len()));
+				stack.push(U256::from(params.data.clone().map_or(0, |l| l.len())));
 			},
 			instructions::CODESIZE => {
 				stack.push(U256::from(code.len()));
@@ -738,10 +751,10 @@ impl Interpreter {
 				stack.push(U256::from(len));
 			},
 			instructions::CALLDATACOPY => {
-				self.copy_data_to_memory(mem, stack, &params.data.clone().unwrap_or(vec![]));
+				self.copy_data_to_memory(mem, stack, &params.data.clone().unwrap_or_else(|| vec![]));
 			},
 			instructions::CODECOPY => {
-				self.copy_data_to_memory(mem, stack, &params.code.clone().unwrap_or(vec![]));
+				self.copy_data_to_memory(mem, stack, &params.code.clone().unwrap_or_else(|| vec![]));
 			},
 			instructions::EXTCODECOPY => {
 				let address = u256_to_address(&stack.pop_back());
@@ -781,7 +794,7 @@ impl Interpreter {
 	fn copy_data_to_memory(&self,
 						   mem: &mut Memory,
 						   stack: &mut Stack<U256>,
-						   data: &Bytes) {
+						   data: &[u8]) {
 		let offset = stack.pop_back();
 		let index = stack.pop_back();
 		let size = stack.pop_back();
@@ -1051,7 +1064,7 @@ impl Interpreter {
 		Ok(())
 	}
 
-	fn find_jump_destinations(&self, code: &Bytes) -> HashSet<CodePosition> {
+	fn find_jump_destinations(&self, code: &[u8]) -> HashSet<CodePosition> {
 		let mut jump_dests = HashSet::new();
 		let mut position = 0;
 
@@ -1066,7 +1079,7 @@ impl Interpreter {
 			position += 1;
 		}
 
-		return jump_dests;
+		jump_dests
 	}
 }
 

src/evm/jit.rs

@@ -64,7 +64,7 @@ impl IntoJit<evmjit::I256> for H256 {
 		for i in 0..self.bytes().len() {
 			let rev = self.bytes().len() - 1 - i;
 			let pos = rev / 8;
-			ret[pos] += (self.bytes()[i] as u64) << (rev % 8) * 8;
+			ret[pos] += (self.bytes()[i] as u64) << ((rev % 8) * 8);
 		}
 		evmjit::I256 { words: ret }
 	}
@@ -218,9 +218,11 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 			}
 		}
 
-		match self.ext.call(&call_gas, 
+		match self.ext.call(
+					  &call_gas, 
+					  &self.address,
 					  &receive_address, 
-					  &value, 
+					  Some(value),
 					  unsafe { slice::from_raw_parts(in_beg, in_size as usize) },
 					  &code_address,
 					  unsafe { slice::from_raw_parts_mut(out_beg, out_size as usize) }) {
@@ -262,7 +264,7 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 			}
 		
 			let bytes_ref: &[u8] = slice::from_raw_parts(beg, size as usize);
-			self.ext.log(topics, bytes_ref.to_vec());
+			self.ext.log(topics, bytes_ref);
 		}
 	}
 
@@ -287,8 +289,8 @@ impl evm::Evm for JitEvm {
 		assert!(params.gas <= U256::from(i64::max_value() as u64), "evmjit max gas is 2 ^ 63");
 		assert!(params.gas_price <= U256::from(i64::max_value() as u64), "evmjit max gas is 2 ^ 63");
 
-		let call_data = params.data.unwrap_or(vec![]);
-		let code = params.code.unwrap_or(vec![]);
+		let call_data = params.data.unwrap_or_else(Vec::new);
+		let code = params.code.unwrap_or_else(Vec::new);
 
 		let mut data = evmjit::RuntimeDataHandle::new();
 		data.gas = params.gas.low_u64() as i64;
@@ -303,7 +305,10 @@ impl evm::Evm for JitEvm {
 		data.address = params.address.into_jit();
 		data.caller = params.sender.into_jit();
 		data.origin = params.origin.into_jit();
-		data.call_value = params.value.into_jit();
+		data.call_value = match params.value {
+			ActionValue::Transfer(val) => val.into_jit(),
+			ActionValue::Apparent(val) => val.into_jit()
+		};
 
 		data.author = ext.env_info().author.clone().into_jit();
 		data.difficulty = ext.env_info().difficulty.into_jit();

src/evm/schedule.rs

@@ -2,67 +2,67 @@
 
 /// Definition of the cost schedule and other parameterisations for the EVM.
 pub struct Schedule {
-	/// TODO [Gav Wood] Please document me
+	/// Does it support exceptional failed code deposit
 	pub exceptional_failed_code_deposit: bool,
-	/// TODO [Gav Wood] Please document me
+	/// Does it have a delegate cal
 	pub have_delegate_call: bool,
-	/// TODO [Tomusdrw] Please document me
+	/// VM stack limit
 	pub stack_limit: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Max number of nested calls/creates
 	pub max_depth: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas prices for instructions in all tiers
 	pub tier_step_gas: [usize; 8],
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for `EXP` opcode
 	pub exp_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Additional gas for `EXP` opcode for each byte of exponent
 	pub exp_byte_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for `SHA3` opcode
 	pub sha3_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Additional gas for `SHA3` opcode for each word of hashed memory
 	pub sha3_word_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for loading from storage
 	pub sload_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for setting new value to storage (`storage==0`, `new!=0`)
 	pub sstore_set_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for altering value in storage
 	pub sstore_reset_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas refund for `SSTORE` clearing (when `storage!=0`, `new==0`)
 	pub sstore_refund_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for `JUMPDEST` opcode
 	pub jumpdest_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for `LOG*`
 	pub log_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Additional gas for data in `LOG*`
 	pub log_data_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Additional gas for each topic in `LOG*`
 	pub log_topic_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for `CREATE` opcode
 	pub create_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for `*CALL*` opcodes
 	pub call_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Stipend for transfer for `CALL|CALLCODE` opcode when `value>0`
 	pub call_stipend: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Additional gas required for value transfer (`CALL|CALLCODE`)
 	pub call_value_transfer_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Additional gas for creating new account (`CALL|CALLCODE`)
 	pub call_new_account_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Refund for SUICIDE
 	pub suicide_refund_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas for used memory
 	pub memory_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Coefficient used to convert memory size to gas price for memory
 	pub quad_coeff_div: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Cost for contract length when executing `CREATE`
 	pub create_data_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Transaction cost
 	pub tx_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// `CREATE` transaction cost
 	pub tx_create_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Additional cost for empty data transaction
 	pub tx_data_zero_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Aditional cost for non-empty data transaction
 	pub tx_data_non_zero_gas: usize,
-	/// TODO [Gav Wood] Please document me
+	/// Gas price for copying memory
 	pub copy_gas: usize,
 }
 

src/evm/tests.rs

@@ -19,7 +19,7 @@ struct FakeExt {
 	logs: Vec<FakeLogEntry>,
 	_suicides: HashSet<Address>,
 	info: EnvInfo,
-	_schedule: Schedule
+	schedule: Schedule
 }
 
 impl FakeExt {
@@ -61,8 +61,9 @@ impl Ext for FakeExt {
 
 	fn call(&mut self, 
 			_gas: &U256, 
-			_address: &Address, 
-			_value: &U256, 
+			_sender_address: &Address, 
+			_receive_address: &Address, 
+			_value: Option<U256>,
 			_data: &[u8], 
 			_code_address: &Address, 
 			_output: &mut [u8]) -> MessageCallResult {
@@ -89,7 +90,7 @@ impl Ext for FakeExt {
 	}
 
 	fn schedule(&self) -> &Schedule {
-		&self._schedule
+		&self.schedule
 	}
 
 	fn env_info(&self) -> &EnvInfo {
@@ -110,7 +111,7 @@ fn test_stack_underflow() {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "01600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
@@ -122,7 +123,7 @@ fn test_stack_underflow() {
 	};
 	
 	match err {
-		evm::Error::StackUnderflow {instruction: _, wanted, on_stack} => {
+		evm::Error::StackUnderflow {wanted, on_stack, ..} => {
 			assert_eq!(wanted, 2);
 			assert_eq!(on_stack, 0);
 		}
@@ -137,7 +138,7 @@ fn test_add(factory: super::Factory) {
   let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff01600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
@@ -157,7 +158,7 @@ fn test_sha3(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "6000600020600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
@@ -177,7 +178,7 @@ fn test_address(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "30600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
@@ -198,7 +199,7 @@ fn test_origin(factory: super::Factory) {
 	let origin = Address::from_str("cd1722f2947def4cf144679da39c4c32bdc35681").unwrap();
 	let code = "32600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.origin = origin.clone();
 	params.gas = U256::from(100_000);
@@ -214,13 +215,14 @@ fn test_origin(factory: super::Factory) {
 	assert_eq!(ext.store.get(&H256::new()).unwrap(), &H256::from_str("000000000000000000000000cd1722f2947def4cf144679da39c4c32bdc35681").unwrap());
 }
 
+// TODO [todr] Fails with Signal 11 on JIT
 evm_test!{test_sender: test_sender_jit, test_sender_int}
 fn test_sender(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let sender = Address::from_str("cd1722f2947def4cf144679da39c4c32bdc35681").unwrap();
 	let code = "33600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.sender = sender.clone();
 	params.gas = U256::from(100_000);
@@ -254,7 +256,7 @@ fn test_extcodecopy(factory: super::Factory) {
 	let code = "333b60006000333c600051600055".from_hex().unwrap();
 	let sender_code = "6005600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.sender = sender.clone();
 	params.gas = U256::from(100_000);
@@ -276,7 +278,7 @@ fn test_log_empty(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "60006000a0".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
@@ -307,7 +309,7 @@ fn test_log_sender(factory: super::Factory) {
 	let sender = Address::from_str("cd1722f3947def4cf144679da39c4c32bdc35681").unwrap();
 	let code = "60ff6000533360206000a1".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.sender = sender.clone();
 	params.gas = U256::from(100_000);
@@ -332,7 +334,7 @@ fn test_blockhash(factory: super::Factory) {
 	let code = "600040600055".from_hex().unwrap();
 	let blockhash = H256::from_str("123400000000000000000000cd1722f2947def4cf144679da39c4c32bdc35681").unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
@@ -354,7 +356,7 @@ fn test_calldataload(factory: super::Factory) {
 	let code = "600135600055".from_hex().unwrap();
 	let data = "0123ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff23".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
@@ -376,7 +378,7 @@ fn test_author(factory: super::Factory) {
 	let author = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "41600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
 	let mut ext = FakeExt::new();
@@ -396,7 +398,7 @@ fn test_timestamp(factory: super::Factory) {
 	let timestamp = 0x1234; 
 	let code = "42600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
 	let mut ext = FakeExt::new();
@@ -416,7 +418,7 @@ fn test_number(factory: super::Factory) {
 	let number = 0x1234; 
 	let code = "43600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
 	let mut ext = FakeExt::new();
@@ -436,7 +438,7 @@ fn test_difficulty(factory: super::Factory) {
 	let difficulty = U256::from(0x1234);
 	let code = "44600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
 	let mut ext = FakeExt::new();
@@ -456,7 +458,7 @@ fn test_gas_limit(factory: super::Factory) {
 	let gas_limit = U256::from(0x1234);
 	let code = "45600055".from_hex().unwrap();
 
-	let mut params = ActionParams::new();
+	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
 	params.code = Some(code);
 	let mut ext = FakeExt::new();

src/executive.rs

@@ -5,6 +5,12 @@ use engine::*;
 use evm::{self, Ext};
 use externalities::*;
 use substate::*;
+use crossbeam;
+
+/// Max depth to avoid stack overflow (when it's reached we start a new thread with VM)
+/// TODO [todr] We probably need some more sophisticated calculations here (limit on my machine 132)
+/// Maybe something like here: https://github.com/ethereum/libethereum/blob/4db169b8504f2b87f7d5a481819cfb959fc65f6c/libethereum/ExtVM.cpp
+const MAX_VM_DEPTH_FOR_THREAD: usize = 128;
 
 /// Returns new address created from address and given nonce.
 pub fn contract_address(address: &Address, nonce: &U256) -> Address {
@@ -75,7 +81,7 @@ impl<'a> Executive<'a> {
 	}
 
 	/// Creates `Externalities` from `Executive`.
-	pub fn to_externalities<'_>(&'_ mut self, origin_info: OriginInfo, substate: &'_ mut Substate, output: OutputPolicy<'_>) -> Externalities {
+	pub fn as_externalities<'_>(&'_ mut self, origin_info: OriginInfo, substate: &'_ mut Substate, output: OutputPolicy<'_>) -> Externalities {
 		Externalities::new(self.state, self.info, self.engine, self.depth, origin_info, substate, output)
 	}
 
@@ -123,8 +129,8 @@ impl<'a> Executive<'a> {
 
 		let mut substate = Substate::new();
 
-		let res = match t.action() {
-			&Action::Create => {
+		let res = match *t.action() {
+			Action::Create => {
 				let new_address = contract_address(&sender, &nonce);
 				let params = ActionParams {
 					code_address: new_address.clone(),
@@ -133,13 +139,13 @@ impl<'a> Executive<'a> {
 					origin: sender.clone(),
 					gas: init_gas,
 					gas_price: t.gas_price,
-					value: t.value,
+					value: ActionValue::Transfer(t.value),
 					code: Some(t.data.clone()),
 					data: None,
 				};
 				self.create(params, &mut substate)
 			},
-			&Action::Call(ref address) => {
+			Action::Call(ref address) => {
 				let params = ActionParams {
 					code_address: address.clone(),
 					address: address.clone(),
@@ -147,7 +153,7 @@ impl<'a> Executive<'a> {
 					origin: sender.clone(),
 					gas: init_gas,
 					gas_price: t.gas_price,
-					value: t.value,
+					value: ActionValue::Transfer(t.value),
 					code: self.state.code(address),
 					data: Some(t.data.clone()),
 				};
@@ -161,6 +167,27 @@ impl<'a> Executive<'a> {
 		Ok(try!(self.finalize(t, substate, res)))
 	}
 
+	fn exec_vm(&mut self, params: ActionParams, unconfirmed_substate: &mut Substate, output_policy: OutputPolicy) -> evm::Result {
+		// Ordinary execution - keep VM in same thread
+		if (self.depth + 1) % MAX_VM_DEPTH_FOR_THREAD != 0 {
+			let mut ext = self.as_externalities(OriginInfo::from(&params), unconfirmed_substate, output_policy);
+			let vm_factory = self.engine.vm_factory();
+			return vm_factory.create().exec(params, &mut ext);
+		}
+
+		// Start in new thread to reset stack
+		// TODO [todr] No thread builder yet, so we need to reset once for a while
+		// https://github.com/aturon/crossbeam/issues/16
+		crossbeam::scope(|scope| {
+			let mut ext = self.as_externalities(OriginInfo::from(&params), unconfirmed_substate, output_policy);
+			let vm_factory = self.engine.vm_factory();
+
+			scope.spawn(move || {
+				vm_factory.create().exec(params, &mut ext)
+			})
+		}).join()
+	}
+
 	/// Calls contract function with given contract params.
 	/// NOTE. It does not finalize the transaction (doesn't do refunds, nor suicides).
 	/// Modifies the substate and the output.
@@ -170,14 +197,16 @@ impl<'a> Executive<'a> {
 		let backup = self.state.clone();
 
 		// at first, transfer value to destination
-		self.state.transfer_balance(&params.sender, &params.address, &params.value);
+		if let ActionValue::Transfer(val) = params.value {
+			self.state.transfer_balance(&params.sender, &params.address, &val);
+		}
 		trace!("Executive::call(params={:?}) self.env_info={:?}", params, self.info);
 
 		if self.engine.is_builtin(&params.code_address) {
 			// if destination is builtin, try to execute it
 			
 			let default = [];
-			let data = if let &Some(ref d) = &params.data { d as &[u8] } else { &default as &[u8] };
+			let data = if let Some(ref d) = params.data { d as &[u8] } else { &default as &[u8] };
 
 			let cost = self.engine.cost_of_builtin(&params.code_address, data);
 			match cost <= params.gas {
@@ -198,8 +227,7 @@ impl<'a> Executive<'a> {
 			let mut unconfirmed_substate = Substate::new();
 
 			let res = {
-				let mut ext = self.to_externalities(OriginInfo::from(&params), &mut unconfirmed_substate, OutputPolicy::Return(output));
-				self.engine.vm_factory().create().exec(params, &mut ext)
+				self.exec_vm(params, &mut unconfirmed_substate, OutputPolicy::Return(output))
 			};
 
 			trace!("exec: sstore-clears={}\n", unconfirmed_substate.sstore_clears_count);
@@ -227,11 +255,12 @@ impl<'a> Executive<'a> {
 		self.state.new_contract(&params.address);
 
 		// then transfer value to it
-		self.state.transfer_balance(&params.sender, &params.address, &params.value);
+		if let ActionValue::Transfer(val) = params.value {
+			self.state.transfer_balance(&params.sender, &params.address, &val);
+		}
 
 		let res = {
-			let mut ext = self.to_externalities(OriginInfo::from(&params), &mut unconfirmed_substate, OutputPolicy::InitContract);
-			self.engine.vm_factory().create().exec(params, &mut ext)
+			self.exec_vm(params, &mut unconfirmed_substate, OutputPolicy::InitContract)
 		};
 		self.enact_result(&res, substate, unconfirmed_substate, backup);
 		res
@@ -248,7 +277,7 @@ impl<'a> Executive<'a> {
 		let refunds_bound = sstore_refunds + suicide_refunds;
 
 		// real ammount to refund
-		let gas_left_prerefund = match &result { &Ok(x) => x, _ => x!(0) };
+		let gas_left_prerefund = match result { Ok(x) => x, _ => x!(0) };
 		let refunded = cmp::min(refunds_bound, (t.gas - gas_left_prerefund) / U256::from(2));
 		let gas_left = gas_left_prerefund + refunded;
 
@@ -265,19 +294,13 @@ impl<'a> Executive<'a> {
 		self.state.add_balance(&self.info.author, &fees_value);
 
 		// perform suicides
-		for address in substate.suicides.iter() {
-			trace!("Killing {}", address);
+		for address in &substate.suicides {
 			self.state.kill_account(address);
 		}
 
 		match result { 
 			Err(evm::Error::Internal) => Err(ExecutionError::Internal),
-			// TODO [ToDr] BadJumpDestination @debris - how to handle that?
-			Err(evm::Error::OutOfGas) 
-				| Err(evm::Error::BadJumpDestination { destination: _ }) 
-				| Err(evm::Error::BadInstruction { instruction: _ }) 
-				| Err(evm::Error::StackUnderflow {instruction: _, wanted: _, on_stack: _})
-				| Err(evm::Error::OutOfStack {instruction: _, wanted: _, limit: _}) => {
+			Err(_) => {
 				Ok(Executed {
 					gas: t.gas,
 					gas_used: t.gas,
@@ -301,16 +324,15 @@ impl<'a> Executive<'a> {
 	}
 
 	fn enact_result(&mut self, result: &evm::Result, substate: &mut Substate, un_substate: Substate, backup: State) {
-		// TODO: handle other evm::Errors same as OutOfGas once they are implemented
-		match result {
-			&Err(evm::Error::OutOfGas)
-				| &Err(evm::Error::BadJumpDestination { destination: _ }) 
-				| &Err(evm::Error::BadInstruction { instruction: _ }) 
-				| &Err(evm::Error::StackUnderflow {instruction: _, wanted: _, on_stack: _})
-				| &Err(evm::Error::OutOfStack {instruction: _, wanted: _, limit: _}) => {
+		match *result {
+			Err(evm::Error::OutOfGas)
+				| Err(evm::Error::BadJumpDestination {..}) 
+				| Err(evm::Error::BadInstruction {.. }) 
+				| Err(evm::Error::StackUnderflow {..})
+				| Err(evm::Error::OutOfStack {..}) => {
 				self.state.revert(backup);
 			},
-			&Ok(_) | &Err(evm::Error::Internal) => substate.accrue(un_substate)
+			Ok(_) | Err(evm::Error::Internal) => substate.accrue(un_substate)
 		}
 	}
 }
@@ -367,12 +389,12 @@ mod tests {
 	fn test_sender_balance(factory: Factory) {
 		let sender = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 		let address = contract_address(&sender, &U256::zero());
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		params.address = address.clone();
 		params.sender = sender.clone();
 		params.gas = U256::from(100_000);
 		params.code = Some("3331600055".from_hex().unwrap());
-		params.value = U256::from(0x7);
+		params.value = ActionValue::Transfer(U256::from(0x7));
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(0x100u64));
 		let info = EnvInfo::new();
@@ -424,13 +446,13 @@ mod tests {
 		let address = contract_address(&sender, &U256::zero());
 		// TODO: add tests for 'callcreate'
 		//let next_address = contract_address(&address, &U256::zero());
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		params.address = address.clone();
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
 		params.code = Some(code.clone());
-		params.value = U256::from(100);
+		params.value = ActionValue::Transfer(U256::from(100));
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(100));
 		let info = EnvInfo::new();
@@ -477,13 +499,13 @@ mod tests {
 		let address = contract_address(&sender, &U256::zero());
 		// TODO: add tests for 'callcreate'
 		//let next_address = contract_address(&address, &U256::zero());
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		params.address = address.clone();
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
 		params.code = Some(code.clone());
-		params.value = U256::from(100);
+		params.value = ActionValue::Transfer(U256::from(100));
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(100));
 		let info = EnvInfo::new();
@@ -528,13 +550,13 @@ mod tests {
 		let sender = Address::from_str("cd1722f3947def4cf144679da39c4c32bdc35681").unwrap();
 		let address = contract_address(&sender, &U256::zero());
 		let next_address = contract_address(&address, &U256::zero());
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		params.address = address.clone();
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
 		params.code = Some(code.clone());
-		params.value = U256::from(100);
+		params.value = ActionValue::Transfer(U256::from(100));
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(100));
 		let info = EnvInfo::new();
@@ -584,12 +606,12 @@ mod tests {
 		let address_b = Address::from_str("945304eb96065b2a98b57a48a06ae28d285a71b5" ).unwrap();
 		let sender = Address::from_str("cd1722f3947def4cf144679da39c4c32bdc35681").unwrap();
 
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		params.address = address_a.clone();
 		params.sender = sender.clone();
 		params.gas = U256::from(100_000);
 		params.code = Some(code_a.clone());
-		params.value = U256::from(100_000);
+		params.value = ActionValue::Transfer(U256::from(100_000));
 
 		let mut state = State::new_temp();
 		state.init_code(&address_a, code_a.clone());
@@ -633,7 +655,7 @@ mod tests {
 		let sender = Address::from_str("cd1722f3947def4cf144679da39c4c32bdc35681").unwrap();
 		let code = "600160005401600055600060006000600060003060e05a03f1600155".from_hex().unwrap();
 		let address = contract_address(&sender, &U256::zero());
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		params.address = address.clone();
 		params.gas = U256::from(100_000);
 		params.code = Some(code.clone());
@@ -789,13 +811,13 @@ mod tests {
 		let address = contract_address(&sender, &U256::zero());
 		// TODO: add tests for 'callcreate'
 		//let next_address = contract_address(&address, &U256::zero());
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		params.address = address.clone();
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(0x0186a0);
 		params.code = Some(code.clone());
-		params.value = U256::from_str("0de0b6b3a7640000").unwrap();
+		params.value = ActionValue::Transfer(U256::from_str("0de0b6b3a7640000").unwrap());
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from_str("152d02c7e14af6800000").unwrap());
 		let info = EnvInfo::new();

src/externalities.rs

@@ -19,7 +19,8 @@ pub enum OutputPolicy<'a> {
 pub struct OriginInfo {
 	address: Address,
 	origin: Address,
-	gas_price: U256
+	gas_price: U256,
+	value: U256
 }
 
 impl OriginInfo {
@@ -28,7 +29,11 @@ impl OriginInfo {
 		OriginInfo {
 			address: params.address.clone(),
 			origin: params.origin.clone(),
-			gas_price: params.gas_price.clone()
+			gas_price: params.gas_price.clone(),
+			value: match params.value {
+				ActionValue::Transfer(val) => val,
+				ActionValue::Apparent(val) => val,
+			}
 		}
 	}
 }
@@ -111,7 +116,7 @@ impl<'a> Ext for Externalities<'a> {
 			origin: self.origin_info.origin.clone(),
 			gas: *gas,
 			gas_price: self.origin_info.gas_price.clone(),
-			value: value.clone(),
+			value: ActionValue::Transfer(value.clone()),
 			code: Some(code.to_vec()),
 			data: None,
 		};
@@ -131,24 +136,29 @@ impl<'a> Ext for Externalities<'a> {
 
 	fn call(&mut self, 
 			gas: &U256, 
-			address: &Address, 
-			value: &U256, 
+			sender_address: &Address, 
+			receive_address: &Address, 
+			value: Option<U256>,
 			data: &[u8], 
 			code_address: &Address, 
 			output: &mut [u8]) -> MessageCallResult {
 
-		let params = ActionParams {
+		let mut params = ActionParams {
+			sender: sender_address.clone(),
+			address: receive_address.clone(), 
+			value: ActionValue::Apparent(self.origin_info.value.clone()),
 			code_address: code_address.clone(),
-			address: address.clone(), 
-			sender: self.origin_info.address.clone(),
 			origin: self.origin_info.origin.clone(),
 			gas: *gas,
 			gas_price: self.origin_info.gas_price.clone(),
-			value: value.clone(),
 			code: self.state.code(code_address),
 			data: Some(data.to_vec()),
 		};
 
+		if let Some(value) = value {
+			params.value = ActionValue::Transfer(value);
+		}
+
 		let mut ex = Executive::from_parent(self.state, self.env_info, self.engine, self.depth);
 
 		match ex.call(params, self.substate, BytesRef::Fixed(output)) {
@@ -158,9 +168,10 @@ impl<'a> Ext for Externalities<'a> {
 	}
 
 	fn extcode(&self, address: &Address) -> Bytes {
-		self.state.code(address).unwrap_or(vec![])
+		self.state.code(address).unwrap_or_else(|| vec![])
 	}
 
+	#[allow(match_ref_pats)]
 	fn ret(&mut self, gas: &U256, data: &[u8]) -> Result<U256, evm::Error> {
 		match &mut self.output {
 			&mut OutputPolicy::Return(BytesRef::Fixed(ref mut slice)) => unsafe {
@@ -204,7 +215,13 @@ impl<'a> Ext for Externalities<'a> {
 	fn suicide(&mut self, refund_address: &Address) {
 		let address = self.origin_info.address.clone();
 		let balance = self.balance(&address);
-		self.state.transfer_balance(&address, refund_address, &balance);
+		if &address == refund_address {
+			// TODO [todr] To be consisted with CPP client we set balance to 0 in that case.
+			self.state.sub_balance(&address, &balance);
+		} else {
+			trace!("Suiciding {} -> {} (xfer: {})", address, refund_address, balance);
+			self.state.transfer_balance(&address, refund_address, &balance);
+		}
 		self.substate.suicides.insert(address);
 	}
 

src/header.rs

@@ -2,7 +2,7 @@ use util::*;
 use basic_types::*;
 use time::now_utc;
 
-/// TODO [Gav Wood] Please document me
+/// Type for Block number
 pub type BlockNumber = u64;
 
 /// A block header.
@@ -11,7 +11,7 @@ pub type BlockNumber = u64;
 /// which is non-specific.
 ///
 /// Doesn't do all that much on its own.
-#[derive(Debug, Clone)]
+#[derive(Default, Debug, Clone)]
 pub struct Header {
 	// TODO: make all private.
 	/// TODO [Gav Wood] Please document me
@@ -171,9 +171,10 @@ impl Header {
 		s.append(&self.gas_used);
 		s.append(&self.timestamp);
 		s.append(&self.extra_data);
-		match with_seal {
-			Seal::With => for b in self.seal.iter() { s.append_raw(&b, 1); },
-			_ => {}
+		if let Seal::With = with_seal {
+			for b in &self.seal { 
+				s.append_raw(&b, 1); 
+			}
 		}
 	}
 
@@ -236,7 +237,7 @@ impl Encodable for Header {
 			self.timestamp.encode(e);
 			self.extra_data.encode(e);
 
-			for b in self.seal.iter() {
+			for b in &self.seal {
 				e.emit_raw(&b);
 			}
 		})

src/lib.rs

@@ -1,8 +1,11 @@
 #![warn(missing_docs)]
 #![feature(cell_extras)]
 #![feature(augmented_assignments)]
-//#![feature(plugin)]
+#![feature(plugin)]
 //#![plugin(interpolate_idents)]
+#![plugin(clippy)]
+#![allow(needless_range_loop, match_bool)]
+
 //! Ethcore's ethereum implementation
 //!
 //! ### Rust version
@@ -73,7 +76,6 @@
 //!       sudo make install
 //!       sudo ldconfig
 //!       ```
-
 #[macro_use]
 extern crate log;
 extern crate rustc_serialize;
@@ -88,6 +90,9 @@ extern crate num_cpus;
 extern crate evmjit;
 #[macro_use]
 extern crate ethcore_util as util;
+extern crate crossbeam;
+
+// NOTE: Add doc parser exception for these pub declarations.
 
 /// TODO [Gav Wood] Please document me
 pub mod common;
@@ -149,6 +154,5 @@ pub mod sync;
 pub mod block;
 /// TODO [arkpar] Please document me
 pub mod verification;
-/// TODO [debris] Please document me
-pub mod queue;
+pub mod block_queue;
 pub mod ethereum;

src/log_entry.rs

@@ -2,7 +2,7 @@ use util::*;
 use basic_types::LogBloom;
 
 /// A single log's entry.
-#[derive(Debug,PartialEq,Eq)]
+#[derive(Default, Debug, Clone, PartialEq, Eq)]
 pub struct LogEntry {
 	/// TODO [Gav Wood] Please document me
 	pub address: Address,

src/null_engine.rs

@@ -11,7 +11,7 @@ pub struct NullEngine {
 }
 
 impl NullEngine {
-	/// TODO [Tomusdrw] Please document me
+	/// Returns new instance of NullEngine with default VM Factory
 	pub fn new_boxed(spec: Spec) -> Box<Engine> {
 		Box::new(NullEngine{
 			spec: spec,

src/pod_account.rs

@@ -31,7 +31,7 @@ impl PodAccount {
 		}
 	}
 
-	/// TODO [Gav Wood] Please document me
+	/// Returns the RLP for this account.
 	pub fn rlp(&self) -> Bytes {
 		let mut stream = RlpStream::new_list(4);
 		stream.append(&self.nonce);
@@ -40,6 +40,18 @@ impl PodAccount {
 		stream.append(&self.code.sha3());
 		stream.out()
 	}
+
+	/// Place additional data into given hash DB.
+	pub fn insert_additional(&self, db: &mut HashDB) {
+		if !self.code.is_empty() {
+			db.insert(&self.code);
+		}
+		let mut r = H256::new();
+		let mut t = SecTrieDBMut::new(db, &mut r);
+		for (k, v) in &self.storage {
+			t.insert(k, &encode(&U256::from(v.as_slice())));
+		}
+	}
 }
 
 impl fmt::Display for PodAccount {

src/pod_state.rs

@@ -1,17 +1,25 @@
 use util::*;
 use pod_account::*;
 
-#[derive(Debug,Clone,PartialEq,Eq)]
+#[derive(Debug,Clone,PartialEq,Eq,Default)]
 /// TODO [Gav Wood] Please document me
 pub struct PodState (BTreeMap<Address, PodAccount>);
 
 impl PodState {
 	/// Contruct a new object from the `m`.
-	pub fn new(m: BTreeMap<Address, PodAccount>) -> PodState { PodState(m) }
+	pub fn new() -> PodState { Default::default() }
+
+	/// Contruct a new object from the `m`.
+	pub fn from(m: BTreeMap<Address, PodAccount>) -> PodState { PodState(m) }
 
 	/// Get the underlying map.
 	pub fn get(&self) -> &BTreeMap<Address, PodAccount> { &self.0 }
 
+	/// Get the root hash of the trie of the RLP of this.
+	pub fn root(&self) -> H256 {
+		sec_trie_root(self.0.iter().map(|(k, v)| (k.to_vec(), v.rlp())).collect())
+	}
+
 	/// Drain object to get the underlying map.
 	pub fn drain(self) -> BTreeMap<Address, PodAccount> { self.0 }
 }
@@ -26,10 +34,10 @@ impl FromJson for PodState {
 			let code = acc.find("code").map(&Bytes::from_json);
 			if balance.is_some() || nonce.is_some() || storage.is_some() || code.is_some() {
 				state.insert(address_from_hex(address), PodAccount{
-					balance: balance.unwrap_or(U256::zero()),
-					nonce: nonce.unwrap_or(U256::zero()),
-					storage: storage.unwrap_or(BTreeMap::new()),
-					code: code.unwrap_or(Vec::new())
+					balance: balance.unwrap_or_else(U256::zero),
+					nonce: nonce.unwrap_or_else(U256::zero),
+					storage: storage.unwrap_or_else(BTreeMap::new),
+					code: code.unwrap_or_else(Vec::new)
 				});
 			}
 			state

src/receipt.rs

@@ -3,7 +3,7 @@ use basic_types::LogBloom;
 use log_entry::LogEntry;
 
 /// Information describing execution of a transaction.
-#[derive(Debug)]
+#[derive(Default, Debug, Clone)]
 pub struct Receipt {
 	/// TODO [Gav Wood] Please document me
 	pub state_root: H256,
@@ -36,7 +36,7 @@ impl RlpStandard for Receipt {
 		// TODO: make work:
 		//s.append(&self.logs);
 		s.append_list(self.logs.len());
-		for l in self.logs.iter() {
+		for l in &self.logs {
 			l.rlp_append(s);
 		}
 	}

src/service.rs

@@ -5,24 +5,37 @@ use error::*;
 use std::env;
 use client::Client;
 
+/// Message type for external and internal events
+#[derive(Clone)]
+pub enum SyncMessage {
+	/// New block has been imported into the blockchain
+	NewChainBlock(Bytes), //TODO: use Cow
+	/// A block is ready 
+	BlockVerified,
+}
+
+/// TODO [arkpar] Please document me
+pub type NetSyncMessage = NetworkIoMessage<SyncMessage>;
+
 /// Client service setup. Creates and registers client and network services with the IO subsystem.
 pub struct ClientService {
 	net_service: NetworkService<SyncMessage>,
-	client: Arc<RwLock<Client>>,
+	client: Arc<Client>,
+	sync: Arc<EthSync>,
 }
 
 impl ClientService {
 	/// Start the service in a separate thread.
-	pub fn start(spec: Spec) -> Result<ClientService, Error> {
-		let mut net_service = try!(NetworkService::start());
+	pub fn start(spec: Spec, net_config: NetworkConfiguration) -> Result<ClientService, Error> {
+		let mut net_service = try!(NetworkService::start(net_config));
 		info!("Starting {}", net_service.host_info());
 		info!("Configured for {} using {} engine", spec.name, spec.engine_name);
 		let mut dir = env::home_dir().unwrap();
 		dir.push(".parity");
 		dir.push(H64::from(spec.genesis_header().hash()).hex());
-		let client = Arc::new(RwLock::new(try!(Client::new(spec, &dir, net_service.io().channel()))));
-		EthSync::register(&mut net_service, client.clone());
-		let client_io = Box::new(ClientIoHandler {
+		let client = try!(Client::new(spec, &dir, net_service.io().channel()));
+		let sync = EthSync::register(&mut net_service, client.clone());
+		let client_io = Arc::new(ClientIoHandler {
 			client: client.clone()
 		});
 		try!(net_service.io().register_handler(client_io));
@@ -30,43 +43,62 @@ impl ClientService {
 		Ok(ClientService {
 			net_service: net_service,
 			client: client,
+			sync: sync,
 		})
 	}
 
+	/// Get the network service.
+	pub fn add_node(&mut self, _enode: &str) {
+		unimplemented!();
+	}
+
 	/// TODO [arkpar] Please document me
 	pub fn io(&mut self) -> &mut IoService<NetSyncMessage> {
 		self.net_service.io()
 	}
 
 	/// TODO [arkpar] Please document me
-	pub fn client(&self) -> Arc<RwLock<Client>> {
+	pub fn client(&self) -> Arc<Client> {
 		self.client.clone()
+	
+	}
+	
+	/// Get shared sync handler
+	pub fn sync(&self) -> Arc<EthSync> {
+		self.sync.clone()
 	}
 }
 
 /// IO interface for the Client handler
 struct ClientIoHandler {
-	client: Arc<RwLock<Client>>
+	client: Arc<Client>
 }
 
+const CLIENT_TICK_TIMER: TimerToken = 0;
+const CLIENT_TICK_MS: u64 = 5000;
+
 impl IoHandler<NetSyncMessage> for ClientIoHandler {
-	fn initialize<'s>(&'s mut self, _io: &mut IoContext<'s, NetSyncMessage>) {
+	fn initialize(&self, io: &IoContext<NetSyncMessage>) {
+		io.register_timer(CLIENT_TICK_TIMER, CLIENT_TICK_MS).expect("Error registering client timer");
 	}
 
-	fn message<'s>(&'s mut self, _io: &mut IoContext<'s, NetSyncMessage>, net_message: &'s mut NetSyncMessage) {
-		match net_message {
-			&mut UserMessage(ref mut message) =>  {
-				match message {
-					&mut SyncMessage::BlockVerified => {
-						self.client.write().unwrap().import_verified_blocks();
-					},
-					_ => {}, // ignore other messages
-				}
-
-			}
-			_ => {}, // ignore other messages
+	fn timeout(&self, _io: &IoContext<NetSyncMessage>, timer: TimerToken) {
+		if timer == CLIENT_TICK_TIMER {
+			self.client.tick();
 		}
+	}
 
+	#[allow(match_ref_pats)]
+	#[allow(single_match)]
+	fn message(&self, io: &IoContext<NetSyncMessage>, net_message: &NetSyncMessage) {
+		if let &UserMessage(ref message) = net_message {
+			match message {
+				&SyncMessage::BlockVerified => {
+					self.client.import_verified_blocks(&io.channel());
+				},
+				_ => {}, // ignore other messages
+			}
+		}
 	}
 }
 

src/spec.rs

@@ -1,6 +1,7 @@
 use common::*;
 use flate2::read::GzDecoder;
 use engine::*;
+use pod_state::*;
 use null_engine::*;
 
 /// Converts file from base64 gzipped bytes to json
@@ -10,7 +11,7 @@ pub fn gzip64res_to_json(source: &[u8]) -> Json {
 	let data = source.from_base64().expect("Genesis block is malformed!");
 	let data_ref: &[u8] = &data;
 	let mut decoder = GzDecoder::new(data_ref).expect("Gzip is invalid");
-	let mut s: String = "".to_string();
+	let mut s: String = "".to_owned();
 	decoder.read_to_string(&mut s).expect("Gzip is invalid");
 	Json::from_str(&s).expect("Json is invalid")
 }
@@ -18,14 +19,14 @@ pub fn gzip64res_to_json(source: &[u8]) -> Json {
 /// Convert JSON value to equivlaent RLP representation.
 // TODO: handle container types.
 fn json_to_rlp(json: &Json) -> Bytes {
-	match json {
-		&Json::Boolean(o) => encode(&(if o {1u64} else {0})),
-		&Json::I64(o) => encode(&(o as u64)),
-		&Json::U64(o) => encode(&o),
-		&Json::String(ref s) if s.len() >= 2 && &s[0..2] == "0x" && U256::from_str(&s[2..]).is_ok() => {
+	match *json {
+		Json::Boolean(o) => encode(&(if o {1u64} else {0})),
+		Json::I64(o) => encode(&(o as u64)),
+		Json::U64(o) => encode(&o),
+		Json::String(ref s) if s.len() >= 2 && &s[0..2] == "0x" && U256::from_str(&s[2..]).is_ok() => {
 			encode(&U256::from_str(&s[2..]).unwrap())
 		},
-		&Json::String(ref s) => {
+		Json::String(ref s) => {
 			encode(s)
 		},
 		_ => panic!()
@@ -40,28 +41,6 @@ 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 {
-	/// TODO [arkpar] Please document me
-	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)]
@@ -73,6 +52,9 @@ pub struct Spec {
 	/// TODO [Gav Wood] Please document me
 	pub engine_name: String,
 
+	/// Known nodes on the network in enode format.
+	pub nodes: Vec<String>,
+
 	// Parameters concerning operation of the specific engine we're using.
 	// Name -> RLP-encoded value
 	/// TODO [Gav Wood] Please document me
@@ -80,7 +62,7 @@ pub struct Spec {
 
 	// Builtin-contracts are here for now but would like to abstract into Engine API eventually.
 	/// TODO [Gav Wood] Please document me
-	pub builtins: HashMap<Address, Builtin>,
+	pub builtins: BTreeMap<Address, Builtin>,
 
 	// Genesis params.
 	/// TODO [Gav Wood] Please document me
@@ -98,7 +80,7 @@ pub struct Spec {
 	/// TODO [arkpar] Please document me
 	pub extra_data: Bytes,
 	/// TODO [Gav Wood] Please document me
-	pub genesis_state: HashMap<Address, GenesisAccount>,
+	genesis_state: PodState,
 	/// TODO [Gav Wood] Please document me
 	pub seal_fields: usize,
 	/// TODO [Gav Wood] Please document me
@@ -108,6 +90,7 @@ pub struct Spec {
 	state_root_memo: RwLock<Option<H256>>,
 }
 
+#[allow(wrong_self_convention)] // because to_engine(self) should be to_engine(&self)
 impl Spec {
 	/// Convert this object into a boxed Engine of the right underlying type.
 	// TODO avoid this hard-coded nastiness - use dynamic-linked plugin framework instead.
@@ -122,11 +105,14 @@ impl Spec {
 	/// Return the state root for the genesis state, memoising accordingly.
 	pub fn state_root(&self) -> H256 {
 		if self.state_root_memo.read().unwrap().is_none() {
-			*self.state_root_memo.write().unwrap() = Some(sec_trie_root(self.genesis_state.iter().map(|(k, v)| (k.to_vec(), v.rlp())).collect()));
+			*self.state_root_memo.write().unwrap() = Some(self.genesis_state.root());
 		}
 		self.state_root_memo.read().unwrap().as_ref().unwrap().clone()
 	}
 
+	/// Get the known knodes of the network in enode format.
+	pub fn nodes(&self) -> &Vec<String> { &self.nodes }
+
 	/// TODO [Gav Wood] Please document me
 	pub fn genesis_header(&self) -> Header {
 		Header {
@@ -167,6 +153,46 @@ impl Spec {
 		ret.append_raw(&empty_list, 1);
 		ret.out()
 	}
+
+	/// Overwrite the genesis components with the given JSON, assuming standard Ethereum test format.
+	pub fn overwrite_genesis(&mut self, genesis: &Json) {
+		let (seal_fields, seal_rlp) = {
+			if genesis.find("mixHash").is_some() && genesis.find("nonce").is_some() {
+				let mut s = RlpStream::new();
+				s.append(&H256::from_json(&genesis["mixHash"]));
+				s.append(&H64::from_json(&genesis["nonce"]));
+				(2, s.out())
+			} else {
+				// backup algo that will work with sealFields/sealRlp (and without).
+				(
+					u64::from_json(&genesis["sealFields"]) as usize,
+					Bytes::from_json(&genesis["sealRlp"])
+				)
+			}
+		};
+		
+		self.parent_hash = H256::from_json(&genesis["parentHash"]);
+		self.author = Address::from_json(&genesis["coinbase"]);
+		self.difficulty = U256::from_json(&genesis["difficulty"]);
+		self.gas_limit = U256::from_json(&genesis["gasLimit"]);
+		self.gas_used = U256::from_json(&genesis["gasUsed"]);
+		self.timestamp = u64::from_json(&genesis["timestamp"]);
+		self.extra_data = Bytes::from_json(&genesis["extraData"]);
+		self.seal_fields = seal_fields;
+		self.seal_rlp = seal_rlp;
+		self.state_root_memo = RwLock::new(genesis.find("stateRoot").and_then(|_| Some(H256::from_json(&genesis["stateRoot"]))));
+	}
+
+	/// Alter the value of the genesis state.
+	pub fn set_genesis_state(&mut self, s: PodState) {
+		self.genesis_state = s;
+		*self.state_root_memo.write().unwrap() = None;
+	}
+
+	/// Returns `false` if the memoized state root is invalid. `true` otherwise.
+	pub fn is_state_root_valid(&self) -> bool {
+		self.state_root_memo.read().unwrap().clone().map_or(true, |sr| sr == self.genesis_state.root())
+	}
 }
 
 impl FromJson for Spec {
@@ -174,8 +200,8 @@ impl FromJson for Spec {
 	fn from_json(json: &Json) -> Spec {
 		// once we commit ourselves to some json parsing library (serde?)
 		// move it to proper data structure
-		let mut state = HashMap::new();
-		let mut builtins = HashMap::new();
+		let mut builtins = BTreeMap::new();
+		let mut state = PodState::new();
 
 		if let Some(&Json::Object(ref accounts)) = json.find("accounts") {
 			for (address, acc) in accounts.iter() {
@@ -185,17 +211,14 @@ impl FromJson for Spec {
 						builtins.insert(addr.clone(), builtin);
 					}
 				}
-				let balance = acc.find("balance").and_then(|x| match x { &Json::String(ref b) => U256::from_dec_str(b).ok(), _ => None });
-				let nonce = acc.find("nonce").and_then(|x| match x { &Json::String(ref b) => U256::from_dec_str(b).ok(), _ => None });
-//				let balance = if let Some(&Json::String(ref b)) = acc.find("balance") {U256::from_dec_str(b).unwrap_or(U256::from(0))} else {U256::from(0)};
-//				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, GenesisAccount { balance: balance.unwrap_or(U256::from(0)), nonce: nonce.unwrap_or(U256::from(0)) });
-				}
 			}
+			state = xjson!(&json["accounts"]);
 		}
 
+		let nodes = if let Some(&Json::Array(ref ns)) = json.find("nodes") {
+			ns.iter().filter_map(|n| if let Json::String(ref s) = *n { Some(s.clone()) } else {None}).collect()
+		} else { Vec::new() };
+
 		let genesis = &json["genesis"];//.as_object().expect("No genesis object in JSON");
 
 		let (seal_fields, seal_rlp) = {
@@ -212,12 +235,12 @@ impl FromJson for Spec {
 				)
 			}
 		};
-
 		
 		Spec {
-			name: json.find("name").map(|j| j.as_string().unwrap()).unwrap_or("unknown").to_string(),
-			engine_name: json["engineName"].as_string().unwrap().to_string(),
+			name: json.find("name").map_or("unknown", |j| j.as_string().unwrap()).to_owned(),
+			engine_name: json["engineName"].as_string().unwrap().to_owned(),
 			engine_params: json_to_rlp_map(&json["params"]),
+			nodes: nodes,
 			builtins: builtins,
 			parent_hash: H256::from_str(&genesis["parentHash"].as_string().unwrap()[2..]).unwrap(),
 			author: Address::from_str(&genesis["author"].as_string().unwrap()[2..]).unwrap(),
@@ -238,16 +261,17 @@ impl Spec {
 	/// Ensure that the given state DB has the trie nodes in for the genesis state.
 	pub fn ensure_db_good(&self, db: &mut HashDB) -> bool {
 		if !db.contains(&self.state_root()) {
-			info!("Populating genesis state...");
 			let mut root = H256::new(); 
 			{
 				let mut t = SecTrieDBMut::new(db, &mut root);
-				for (address, account) in self.genesis_state.iter() {
+				for (address, account) in self.genesis_state.get().iter() {
 					t.insert(address.as_slice(), &account.rlp());
 				}
 			}
+			for (_, account) in self.genesis_state.get().iter() {
+				account.insert_additional(db);
+			}
 			assert!(db.contains(&self.state_root()));
-			info!("Genesis state is ready");
 			true
 		} else { false }
 	}

src/state.rs

@@ -3,7 +3,7 @@ use engine::Engine;
 use executive::Executive;
 use pod_account::*;
 use pod_state::*;
-use state_diff::*;
+//use state_diff::*;	// TODO: uncomment once to_pod() works correctly.
 
 /// TODO [Gav Wood] Please document me
 pub type ApplyResult = Result<Receipt, Error>;
@@ -88,22 +88,22 @@ impl State {
 
 	/// Get the balance of account `a`.
 	pub fn balance(&self, a: &Address) -> U256 {
-		self.get(a, false).as_ref().map(|account| account.balance().clone()).unwrap_or(U256::from(0u8))
+		self.get(a, false).as_ref().map_or(U256::zero(), |account| account.balance().clone())
 	}
 
 	/// Get the nonce of account `a`.
 	pub fn nonce(&self, a: &Address) -> U256 {
-		self.get(a, false).as_ref().map(|account| account.nonce().clone()).unwrap_or(U256::from(0u8))
+		self.get(a, false).as_ref().map_or(U256::zero(), |account| account.nonce().clone())
 	}
 
 	/// Mutate storage of account `a` so that it is `value` for `key`.
 	pub fn storage_at(&self, a: &Address, key: &H256) -> H256 {
-		self.get(a, false).as_ref().map(|a|a.storage_at(&self.db, key)).unwrap_or(H256::new())	
+		self.get(a, false).as_ref().map_or(H256::new(), |a|a.storage_at(&self.db, key))	
 	}
 
 	/// Mutate storage of account `a` so that it is `value` for `key`.
 	pub fn code(&self, a: &Address) -> Option<Bytes> {
-		self.get(a, true).as_ref().map(|a|a.code().map(|x|x.to_vec())).unwrap_or(None)
+		self.get(a, true).as_ref().map_or(None, |a|a.code().map(|x|x.to_vec()))
 	}
 
 	/// Add `incr` to the balance of account `a`.
@@ -145,16 +145,16 @@ impl State {
 	/// Execute a given transaction.
 	/// This will change the state accordingly.
 	pub fn apply(&mut self, env_info: &EnvInfo, engine: &Engine, t: &Transaction) -> ApplyResult {
-
-		let old = self.to_pod();
+//		let old = self.to_pod();
 
 		let e = try!(Executive::new(self, env_info, engine).transact(t));
 		//println!("Executed: {:?}", e);
 
-		trace!("Applied transaction. Diff:\n{}\n", StateDiff::diff_pod(&old, &self.to_pod()));
+		// TODO uncomment once to_pod() works correctly.
+//		trace!("Applied transaction. Diff:\n{}\n", StateDiff::diff_pod(&old, &self.to_pod()));
 		self.commit();
 		let receipt = Receipt::new(self.root().clone(), e.cumulative_gas_used, e.logs);
-		trace!("Transaction receipt: {:?}", receipt);
+//		trace!("Transaction receipt: {:?}", receipt);
 		Ok(receipt)
 	}
 
@@ -170,6 +170,7 @@ impl State {
 
 	/// Commit accounts to SecTrieDBMut. This is similar to cpp-ethereum's dev::eth::commit.
 	/// `accounts` is mutable because we may need to commit the code or storage and record that.
+	#[allow(match_ref_pats)]
 	pub fn commit_into(db: &mut HashDB, root: &mut H256, accounts: &mut HashMap<Address, Option<Account>>) {
 		// first, commit the sub trees.
 		// TODO: is this necessary or can we dispense with the `ref mut a` for just `a`?
@@ -186,9 +187,9 @@ impl State {
 		{
 			let mut trie = SecTrieDBMut::from_existing(db, root);
 			for (address, ref a) in accounts.iter() {
-				match a {
-					&&Some(ref account) => trie.insert(address, &account.rlp()),
-					&&None => trie.remove(address),
+				match **a {
+					Some(ref account) => trie.insert(address, &account.rlp()),
+					None => trie.remove(address),
 				}
 			}
 		}
@@ -210,7 +211,7 @@ impl State {
 	pub fn to_hashmap_pod(&self) -> HashMap<Address, PodAccount> {
 		// TODO: handle database rather than just the cache.
 		self.cache.borrow().iter().fold(HashMap::new(), |mut m, (add, opt)| {
-			if let &Some(ref acc) = opt {
+			if let Some(ref acc) = *opt {
 				m.insert(add.clone(), PodAccount::from_account(acc));
 			}
 			m
@@ -220,8 +221,8 @@ impl State {
 	/// Populate a PodAccount map from this state.
 	pub fn to_pod(&self) -> PodState {
 		// TODO: handle database rather than just the cache.
-		PodState::new(self.cache.borrow().iter().fold(BTreeMap::new(), |mut m, (add, opt)| {
-			if let &Some(ref acc) = opt {
+		PodState::from(self.cache.borrow().iter().fold(BTreeMap::new(), |mut m, (add, opt)| {
+			if let Some(ref acc) = *opt {
 				m.insert(add.clone(), PodAccount::from_account(acc));
 			}
 			m

src/state_diff.rs

@@ -15,7 +15,7 @@ impl StateDiff {
 
 impl fmt::Display for StateDiff {
 	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-		for (add, acc) in self.0.iter() {
+		for (add, acc) in &self.0 {
 			try!(write!(f, "{} {}: {}", acc.existance(), add, acc));
 		}
 		Ok(())
@@ -32,8 +32,8 @@ mod test {
 
 	#[test]
 	fn create_delete() {
-		let a = PodState::new(map![ x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]) ]);
-		assert_eq!(StateDiff::diff_pod(&a, &PodState::new(map![])), StateDiff(map![
+		let a = PodState::from(map![ x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]) ]);
+		assert_eq!(StateDiff::diff_pod(&a, &PodState::new()), StateDiff(map![
 			x!(1) => AccountDiff{
 				balance: Diff::Died(x!(69)),
 				nonce: Diff::Died(x!(0)),
@@ -41,7 +41,7 @@ mod test {
 				storage: map![],
 			}
 		]));
-		assert_eq!(StateDiff::diff_pod(&PodState::new(map![]), &a), StateDiff(map![
+		assert_eq!(StateDiff::diff_pod(&PodState::new(), &a), StateDiff(map![
 			x!(1) => AccountDiff{
 				balance: Diff::Born(x!(69)),
 				nonce: Diff::Born(x!(0)),
@@ -53,8 +53,8 @@ mod test {
 
 	#[test]
 	fn create_delete_with_unchanged() {
-		let a = PodState::new(map![ x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]) ]);
-		let b = PodState::new(map![
+		let a = PodState::from(map![ x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]) ]);
+		let b = PodState::from(map![
 			x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]),
 			x!(2) => PodAccount::new(x!(69), x!(0), vec![], map![])
 		]);
@@ -78,11 +78,11 @@ mod test {
 
 	#[test]
 	fn change_with_unchanged() {
-		let a = PodState::new(map![
+		let a = PodState::from(map![
 			x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]),
 			x!(2) => PodAccount::new(x!(69), x!(0), vec![], map![])
 		]);
-		let b = PodState::new(map![
+		let b = PodState::from(map![
 			x!(1) => PodAccount::new(x!(69), x!(1), vec![], map![]),
 			x!(2) => PodAccount::new(x!(69), x!(0), vec![], map![])
 		]);

src/sync/chain.rs

@@ -107,6 +107,10 @@ pub struct SyncStatus {
 	pub blocks_total: usize,
 	/// Number of blocks downloaded so far.
 	pub blocks_received: usize,
+	/// Total number of connected peers
+	pub num_peers: usize,
+	/// Total number of active peers
+	pub num_active_peers: usize,
 }
 
 #[derive(PartialEq, Eq, Debug)]
@@ -195,8 +199,10 @@ impl ChainSync {
 			start_block_number: self.starting_block,
 			last_imported_block_number: self.last_imported_block,
 			highest_block_number: self.highest_block,
-			blocks_total: (self.last_imported_block - self.starting_block) as usize,
-			blocks_received: (self.highest_block - self.starting_block) as usize,
+			blocks_received: (self.last_imported_block - self.starting_block) as usize,
+			blocks_total: (self.highest_block - self.starting_block) as usize,
+			num_peers: self.peers.len(),
+			num_active_peers: self.peers.values().filter(|p| p.asking != PeerAsking::Nothing).count(),
 		}
 	}
 
@@ -212,7 +218,7 @@ impl ChainSync {
 		self.downloading_bodies.clear();
 		self.headers.clear();
 		self.bodies.clear();
-		for (_, ref mut p) in self.peers.iter_mut() {
+		for (_, ref mut p) in &mut self.peers {
 			p.asking_blocks.clear();
 		}
 		self.header_ids.clear();
@@ -268,6 +274,7 @@ impl ChainSync {
 		Ok(())
 	}
 
+	#[allow(cyclomatic_complexity)]
 	/// Called by peer once it has new block headers during sync
 	fn on_peer_block_headers(&mut self, io: &mut SyncIo, peer_id: PeerId, r: &UntrustedRlp) -> Result<(), PacketDecodeError> {
 		self.reset_peer_asking(peer_id, PeerAsking::BlockHeaders);
@@ -375,7 +382,7 @@ impl ChainSync {
 				transactions_root: tx_root,
 				uncles: uncles
 			};
-			match self.header_ids.get(&header_id).map(|n| *n) {
+			match self.header_ids.get(&header_id).cloned() {
 				Some(n) => {
 					self.header_ids.remove(&header_id);
 					self.bodies.insert_item(n, body.as_raw().to_vec());
@@ -408,7 +415,7 @@ impl ChainSync {
 				Err(ImportError::AlreadyQueued) => {
 					trace!(target: "sync", "New block already queued {:?}", h);
 				},
-				Ok(()) => {
+				Ok(_) => {
 					trace!(target: "sync", "New block queued {:?}", h);
 				},
 				Err(e) => {
@@ -424,6 +431,10 @@ impl ChainSync {
 			let peer_difficulty = self.peers.get_mut(&peer_id).expect("ChainSync: unknown peer").difficulty;
 			if difficulty > peer_difficulty {
 				trace!(target: "sync", "Received block {:?}  with no known parent. Peer needs syncing...", h);
+				{
+					let peer = self.peers.get_mut(&peer_id).expect("ChainSync: unknown peer");
+					peer.latest = header_view.sha3();
+				}
 				self.sync_peer(io, peer_id, true);
 			}
 		}
@@ -464,6 +475,9 @@ impl ChainSync {
 				}
 			}
 		};
+		if max_height != x!(0) {
+			self.sync_peer(io, peer_id, true);
+		}
 		Ok(())
 	}
 
@@ -540,7 +554,7 @@ impl ChainSync {
 	fn request_blocks(&mut self, io: &mut SyncIo, peer_id: PeerId) {
 		self.clear_peer_download(peer_id);
 
-		if io.chain().queue_status().full {
+		if io.chain().queue_info().full {
 			self.pause_sync();
 			return;
 		}
@@ -666,7 +680,7 @@ impl ChainSync {
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
 					},
-					Ok(()) => {
+					Ok(_) => {
 						trace!(target: "sync", "Block queued {:?}", h);
 						self.last_imported_block = headers.0 + i as BlockNumber;
 						self.last_imported_hash = h.clone();
@@ -699,16 +713,13 @@ impl ChainSync {
 	/// Used to recover from an error and re-download parts of the chain detected as bad.
 	fn remove_downloaded_blocks(&mut self, start: BlockNumber) {
 		for n in self.headers.get_tail(&start) {
-			match self.headers.find_item(&n) {
-				Some(ref header_data) => {
-					let header_to_delete = HeaderView::new(&header_data.data);
-					let header_id = HeaderId {
-						transactions_root: header_to_delete.transactions_root(),
-						uncles: header_to_delete.uncles_hash()
-					};
-					self.header_ids.remove(&header_id);
-				},
-				None => {}
+			if let Some(ref header_data) = self.headers.find_item(&n) {
+				let header_to_delete = HeaderView::new(&header_data.data);
+				let header_id = HeaderId {
+					transactions_root: header_to_delete.transactions_root(),
+					uncles: header_to_delete.uncles_hash()
+				};
+				self.header_ids.remove(&header_id);
 			}
 			self.downloading_bodies.remove(&n);
 			self.downloading_headers.remove(&n);
@@ -796,12 +807,9 @@ impl ChainSync {
 		packet.append(&chain.best_block_hash);
 		packet.append(&chain.genesis_hash);
 		//TODO: handle timeout for status request
-		match io.send(peer_id, STATUS_PACKET, packet.out()) {
-			Err(e) => {
-				warn!(target:"sync", "Error sending status request: {:?}", e);
-				io.disable_peer(peer_id);
-			}
-			Ok(_) => ()
+		if let Err(e) = io.send(peer_id, STATUS_PACKET, packet.out()) {
+			warn!(target:"sync", "Error sending status request: {:?}", e);
+			io.disable_peer(peer_id);
 		}
 	}
 
@@ -837,12 +845,9 @@ impl ChainSync {
 		let mut data = Bytes::new();
 		let inc = (skip + 1) as BlockNumber;
 		while number <= last && number > 0 && count < max_count {
-			match io.chain().block_header_at(number) {
-				Some(mut hdr) => {
-					data.append(&mut hdr);
-					count += 1;
-				}
-				None => {}
+			if let Some(mut hdr) = io.chain().block_header_at(number) {
+				data.append(&mut hdr);
+				count += 1;
 			}
 			if reverse {
 				if number <= inc {
@@ -874,12 +879,9 @@ impl ChainSync {
 		let mut added = 0usize;
 		let mut data = Bytes::new();
 		for i in 0..count {
-			match io.chain().block_body(&try!(r.val_at::<H256>(i))) {
-				Some(mut hdr) => {
-					data.append(&mut hdr);
-					added += 1;
-				}
-				None => {}
+			if let Some(mut hdr) = io.chain().block_body(&try!(r.val_at::<H256>(i))) {
+				data.append(&mut hdr);
+				added += 1;
 			}
 		}
 		let mut rlp = RlpStream::new_list(added);
@@ -901,12 +903,9 @@ impl ChainSync {
 		let mut added = 0usize;
 		let mut data = Bytes::new();
 		for i in 0..count {
-			match io.chain().state_data(&try!(r.val_at::<H256>(i))) {
-				Some(mut hdr) => {
-					data.append(&mut hdr);
-					added += 1;
-				}
-				None => {}
+			if let Some(mut hdr) = io.chain().state_data(&try!(r.val_at::<H256>(i))) {
+				data.append(&mut hdr);
+				added += 1;
 			}
 		}
 		let mut rlp = RlpStream::new_list(added);
@@ -927,12 +926,9 @@ impl ChainSync {
 		let mut added = 0usize;
 		let mut data = Bytes::new();
 		for i in 0..count {
-			match io.chain().block_receipts(&try!(r.val_at::<H256>(i))) {
-				Some(mut hdr) => {
-					data.append(&mut hdr);
-					added += 1;
-				}
-				None => {}
+			if let Some(mut hdr) = io.chain().block_receipts(&try!(r.val_at::<H256>(i))) {
+				data.append(&mut hdr);
+				added += 1;
 			}
 		}
 		let mut rlp = RlpStream::new_list(added);
@@ -967,7 +963,7 @@ impl ChainSync {
 	}
 
 	/// Maintain other peers. Send out any new blocks and transactions
-	pub fn maintain_sync(&mut self, _io: &mut SyncIo) {
+	pub fn _maintain_sync(&mut self, _io: &mut SyncIo) {
 	}
 }
 

src/sync/io.rs

@@ -1,7 +1,7 @@
 use client::BlockChainClient;
 use util::{NetworkContext, PeerId, PacketId,};
 use util::error::UtilError;
-use sync::SyncMessage;
+use service::SyncMessage;
 
 /// IO interface for the syning handler.
 /// Provides peer connection management and an interface to the blockchain client.
@@ -14,7 +14,7 @@ pub trait SyncIo {
 	/// 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;
+	fn chain(&self) -> &BlockChainClient;
 	/// Returns peer client identifier string
 	fn peer_info(&self, peer_id: PeerId) -> String {
 		peer_id.to_string()
@@ -22,14 +22,14 @@ pub trait SyncIo {
 }
 
 /// Wraps `NetworkContext` and the blockchain client
-pub struct NetSyncIo<'s, 'h, 'io> where 'h: 's, 'io: 'h {
-	network: &'s mut NetworkContext<'h, 'io, SyncMessage>,
-	chain: &'s mut BlockChainClient
+pub struct NetSyncIo<'s, 'h> where 'h: 's {
+	network: &'s NetworkContext<'h, SyncMessage>,
+	chain: &'s BlockChainClient
 }
 
-impl<'s, 'h, 'io> NetSyncIo<'s, 'h, 'io> {
+impl<'s, 'h> NetSyncIo<'s, 'h> {
 	/// Creates a new instance from the `NetworkContext` and the blockchain client reference.
-	pub fn new(network: &'s mut NetworkContext<'h, 'io, SyncMessage>, chain: &'s mut BlockChainClient) -> NetSyncIo<'s,'h,'io> {
+	pub fn new(network: &'s NetworkContext<'h, SyncMessage>, chain: &'s BlockChainClient) -> NetSyncIo<'s, 'h> {
 		NetSyncIo {
 			network: network,
 			chain: chain,
@@ -37,7 +37,7 @@ impl<'s, 'h, 'io> NetSyncIo<'s, 'h, 'io> {
 	}
 }
 
-impl<'s, 'h, 'op> SyncIo for NetSyncIo<'s, 'h, 'op> {
+impl<'s, 'h> SyncIo for NetSyncIo<'s, 'h> {
 	fn disable_peer(&mut self, peer_id: PeerId) {
 		self.network.disable_peer(peer_id);
 	}
@@ -50,7 +50,7 @@ impl<'s, 'h, 'op> SyncIo for NetSyncIo<'s, 'h, 'op> {
 		self.network.send(peer_id, packet_id, data)
 	}
 
-	fn chain<'a>(&'a mut self) -> &'a mut BlockChainClient {
+	fn chain(&self) -> &BlockChainClient {
 		self.chain
 	}
 

src/sync/mod.rs

@@ -9,15 +9,15 @@
 /// extern crate ethcore;
 /// use std::env;
 /// use std::sync::Arc;
-/// use util::network::NetworkService;
+/// use util::network::{NetworkService, NetworkConfiguration};
 /// use ethcore::client::Client;
 /// use ethcore::sync::EthSync;
 /// use ethcore::ethereum;
 ///
 /// fn main() {
-/// 	let mut service = NetworkService::start().unwrap();
+/// 	let mut service = NetworkService::start(NetworkConfiguration::new()).unwrap();
 /// 	let dir = env::temp_dir();
-/// 	let client = Arc::new(Client::new(ethereum::new_frontier(), &dir).unwrap());
+/// 	let client = Client::new(ethereum::new_frontier(), &dir, service.io().channel()).unwrap();
 /// 	EthSync::register(&mut service, client);
 /// }
 /// ```
@@ -25,10 +25,9 @@
 use std::ops::*;
 use std::sync::*;
 use client::Client;
-use util::network::{NetworkProtocolHandler, NetworkService, NetworkContext, PeerId, NetworkIoMessage};
-use util::TimerToken;
-use util::Bytes;
+use util::network::{NetworkProtocolHandler, NetworkService, NetworkContext, PeerId};
 use sync::chain::ChainSync;
+use service::SyncMessage;
 use sync::io::NetSyncIo;
 
 mod chain;
@@ -38,76 +37,57 @@ mod range_collection;
 #[cfg(test)]
 mod tests;
 
-/// Message type for external events
-pub enum SyncMessage {
-	/// New block has been imported into the blockchain
-	NewChainBlock(Bytes),
-	/// A block is ready 
-	BlockVerified,
-}
-
-/// TODO [arkpar] Please document me
-pub type NetSyncMessage = NetworkIoMessage<SyncMessage>;
-
 /// Ethereum network protocol handler
 pub struct EthSync {
 	/// Shared blockchain client. TODO: this should evetually become an IPC endpoint
-	chain: Arc<RwLock<Client>>,
+	chain: Arc<Client>,
 	/// Sync strategy
-	sync: ChainSync
+	sync: RwLock<ChainSync>
 }
 
 pub use self::chain::SyncStatus;
 
 impl EthSync {
 	/// Creates and register protocol with the network service
-	pub fn register(service: &mut NetworkService<SyncMessage>, chain: Arc<RwLock<Client>>) {
-		let sync = Box::new(EthSync {
+	pub fn register(service: &mut NetworkService<SyncMessage>, chain: Arc<Client>) -> Arc<EthSync> {
+		let sync = Arc::new(EthSync {
 			chain: chain,
-			sync: ChainSync::new(),
+			sync: RwLock::new(ChainSync::new()),
 		});
-		service.register_protocol(sync, "eth", &[62u8, 63u8]).expect("Error registering eth protocol handler");
+		service.register_protocol(sync.clone(), "eth", &[62u8, 63u8]).expect("Error registering eth protocol handler");
+		sync
 	}
 
 	/// Get sync status
 	pub fn status(&self) -> SyncStatus {
-		self.sync.status()
+		self.sync.read().unwrap().status()
 	}
 
 	/// Stop sync
 	pub fn stop(&mut self, io: &mut NetworkContext<SyncMessage>) {
-		self.sync.abort(&mut NetSyncIo::new(io, self.chain.write().unwrap().deref_mut()));
+		self.sync.write().unwrap().abort(&mut NetSyncIo::new(io, self.chain.deref()));
 	}
 
 	/// Restart sync
 	pub fn restart(&mut self, io: &mut NetworkContext<SyncMessage>) {
-		self.sync.restart(&mut NetSyncIo::new(io, self.chain.write().unwrap().deref_mut()));
+		self.sync.write().unwrap().restart(&mut NetSyncIo::new(io, self.chain.deref()));
 	}
 }
 
 impl NetworkProtocolHandler<SyncMessage> for EthSync {
-	fn initialize(&mut self, io: &mut NetworkContext<SyncMessage>) {
-		self.sync.restart(&mut NetSyncIo::new(io, self.chain.write().unwrap().deref_mut()));
-		io.register_timer(1000).unwrap();
+	fn initialize(&self, _io: &NetworkContext<SyncMessage>) {
 	}
 
-	fn read(&mut self, io: &mut NetworkContext<SyncMessage>, peer: &PeerId, packet_id: u8, data: &[u8]) {
-		self.sync.on_packet(&mut NetSyncIo::new(io, self.chain.write().unwrap().deref_mut()) , *peer, packet_id, data);
+	fn read(&self, io: &NetworkContext<SyncMessage>, peer: &PeerId, packet_id: u8, data: &[u8]) {
+		self.sync.write().unwrap().on_packet(&mut NetSyncIo::new(io, self.chain.deref()) , *peer, packet_id, data);
 	}
 
-	fn connected(&mut self, io: &mut NetworkContext<SyncMessage>, peer: &PeerId) {
-		self.sync.on_peer_connected(&mut NetSyncIo::new(io, self.chain.write().unwrap().deref_mut()), *peer);
+	fn connected(&self, io: &NetworkContext<SyncMessage>, peer: &PeerId) {
+		self.sync.write().unwrap().on_peer_connected(&mut NetSyncIo::new(io, self.chain.deref()), *peer);
 	}
 
-	fn disconnected(&mut self, io: &mut NetworkContext<SyncMessage>, peer: &PeerId) {
-		self.sync.on_peer_aborting(&mut NetSyncIo::new(io, self.chain.write().unwrap().deref_mut()), *peer);
-	}
-
-	fn timeout(&mut self, io: &mut NetworkContext<SyncMessage>, _timer: TimerToken) {
-		self.sync.maintain_sync(&mut NetSyncIo::new(io, self.chain.write().unwrap().deref_mut()));
-	}
-
-	fn message(&mut self, _io: &mut NetworkContext<SyncMessage>, _message: &SyncMessage) {
+	fn disconnected(&self, io: &NetworkContext<SyncMessage>, peer: &PeerId) {
+		self.sync.write().unwrap().on_peer_aborting(&mut NetSyncIo::new(io, self.chain.deref()), *peer);
 	}
 }
 

src/sync/range_collection.rs

@@ -29,7 +29,7 @@ pub trait RangeCollection<K, V> {
 	/// Remove all elements >= `tail`
 	fn insert_item(&mut self, key: K, value: V);
 	/// Get an iterator over ranges
-	fn range_iter<'c>(&'c self) -> RangeIterator<'c, K, V>;
+	fn range_iter(& self) -> RangeIterator<K, V>;
 }
 
 /// Range iterator. For each range yelds a key for the first element of the range and a vector of values.
@@ -60,7 +60,7 @@ impl<'c, K:'c, V:'c> Iterator for RangeIterator<'c, K, V> where K: Add<Output =
 }
 
 impl<K, V> RangeCollection<K, V> for Vec<(K, Vec<V>)> where K: Ord + PartialEq + Add<Output = K> + Sub<Output = K> + Copy + FromUsize + ToUsize {
-	fn range_iter<'c>(&'c self) -> RangeIterator<'c, K, V> {
+	fn range_iter(&self) -> RangeIterator<K, V> {
 		RangeIterator {
 			range: self.len(),
 			collection: self
@@ -191,6 +191,7 @@ impl<K, V> RangeCollection<K, V> for Vec<(K, Vec<V>)> where K: Ord + PartialEq +
 }
 
 #[test]
+#[allow(cyclomatic_complexity)]
 fn test_range() {
 	use std::cmp::{Ordering};
 

src/sync/tests.rs

@@ -1,38 +1,40 @@
 use util::*;
-use client::{BlockChainClient, BlockStatus, TreeRoute, BlockQueueStatus, BlockChainInfo};
+use client::{BlockChainClient, BlockStatus, TreeRoute, BlockChainInfo};
+use block_queue::BlockQueueInfo;
 use header::{Header as BlockHeader, BlockNumber};
 use error::*;
 use sync::io::SyncIo;
 use sync::chain::ChainSync;
 
 struct TestBlockChainClient {
-	blocks: HashMap<H256, Bytes>,
- 	numbers: HashMap<usize, H256>,
+	blocks: RwLock<HashMap<H256, Bytes>>,
+ 	numbers: RwLock<HashMap<usize, H256>>,
 	genesis_hash: H256,
-	last_hash: H256,
-	difficulty: U256
+	last_hash: RwLock<H256>,
+	difficulty: RwLock<U256>,
 }
 
 impl TestBlockChainClient {
 	fn new() -> TestBlockChainClient {
 
 		let mut client = TestBlockChainClient {
-			blocks: HashMap::new(),
-			numbers: HashMap::new(),
+			blocks: RwLock::new(HashMap::new()),
+			numbers: RwLock::new(HashMap::new()),
 			genesis_hash: H256::new(),
-			last_hash: H256::new(),
-			difficulty: From::from(0),
+			last_hash: RwLock::new(H256::new()),
+			difficulty: RwLock::new(From::from(0)),
 		};
 		client.add_blocks(1, true); // add genesis block
-		client.genesis_hash = client.last_hash.clone();
+		client.genesis_hash = client.last_hash.read().unwrap().clone();
 		client
 	}
 
 	pub fn add_blocks(&mut self, count: usize, empty: bool) {
-		for n in self.numbers.len()..(self.numbers.len() + count) {
+		let len = self.numbers.read().unwrap().len();
+		for n in len..(len + count) {
 			let mut header = BlockHeader::new();
 			header.difficulty = From::from(n);
-			header.parent_hash = self.last_hash.clone();
+			header.parent_hash = self.last_hash.read().unwrap().clone();
 			header.number = n as BlockNumber;
 			let mut uncles = RlpStream::new_list(if empty {0} else {1});
 			if !empty {
@@ -49,13 +51,17 @@ impl TestBlockChainClient {
 }
 
 impl BlockChainClient for TestBlockChainClient {
+	fn block_total_difficulty(&self, _h: &H256) -> Option<U256> {
+		unimplemented!();
+	}
+
 	fn block_header(&self, h: &H256) -> Option<Bytes> {
-		self.blocks.get(h).map(|r| Rlp::new(r).at(0).as_raw().to_vec())
+		self.blocks.read().unwrap().get(h).map(|r| Rlp::new(r).at(0).as_raw().to_vec())
 
 	}
 
 	fn block_body(&self, h: &H256) -> Option<Bytes> {
-		self.blocks.get(h).map(|r| {
+		self.blocks.read().unwrap().get(h).map(|r| {
 			let mut stream = RlpStream::new_list(2);
 			stream.append_raw(Rlp::new(&r).at(1).as_raw(), 1);
 			stream.append_raw(Rlp::new(&r).at(2).as_raw(), 1);
@@ -64,30 +70,34 @@ impl BlockChainClient for TestBlockChainClient {
 	}
 
 	fn block(&self, h: &H256) -> Option<Bytes> {
-		self.blocks.get(h).map(|b| b.clone())
+		self.blocks.read().unwrap().get(h).cloned()
 	}
 
 	fn block_status(&self, h: &H256) -> BlockStatus {
-		match self.blocks.get(h) {
+		match self.blocks.read().unwrap().get(h) {
 			Some(_) => BlockStatus::InChain,
 			None => BlockStatus::Unknown
 		}
 	}
 
+	fn block_total_difficulty_at(&self, _number: BlockNumber) -> Option<U256> {
+		unimplemented!();
+	}
+
 	fn block_header_at(&self, n: BlockNumber) -> Option<Bytes> {
-		self.numbers.get(&(n as usize)).and_then(|h| self.block_header(h))
+		self.numbers.read().unwrap().get(&(n as usize)).and_then(|h| self.block_header(h))
 	}
 
 	fn block_body_at(&self, n: BlockNumber) -> Option<Bytes> {
-		self.numbers.get(&(n as usize)).and_then(|h| self.block_body(h))
+		self.numbers.read().unwrap().get(&(n as usize)).and_then(|h| self.block_body(h))
 	}
 
 	fn block_at(&self, n: BlockNumber) -> Option<Bytes> {
-		self.numbers.get(&(n as usize)).map(|h| self.blocks.get(h).unwrap().clone())
+		self.numbers.read().unwrap().get(&(n as usize)).map(|h| self.blocks.read().unwrap().get(h).unwrap().clone())
 	}
 
 	fn block_status_at(&self, n: BlockNumber) -> BlockStatus {
-		if (n as usize) < self.blocks.len() {
+		if (n as usize) < self.blocks.read().unwrap().len() {
 			BlockStatus::InChain
 		} else {
 			BlockStatus::Unknown
@@ -110,14 +120,15 @@ impl BlockChainClient for TestBlockChainClient {
 		None
 	}
 
-	fn import_block(&mut self, b: Bytes) -> ImportResult {
+	fn import_block(&self, b: Bytes) -> ImportResult {
 		let header = Rlp::new(&b).val_at::<BlockHeader>(0);
+		let h = header.hash();
 		let number: usize = header.number as usize;
-		if number > self.blocks.len() {
-			panic!("Unexpected block number. Expected {}, got {}", self.blocks.len(), number);
+		if number > self.blocks.read().unwrap().len() {
+			panic!("Unexpected block number. Expected {}, got {}", self.blocks.read().unwrap().len(), number);
 		}
 		if number > 0 {
-			match self.blocks.get(&header.parent_hash) {
+			match self.blocks.read().unwrap().get(&header.parent_hash) {
 				Some(parent) => {
 					let parent = Rlp::new(parent).val_at::<BlockHeader>(0);
 					if parent.number != (header.number - 1) {
@@ -129,43 +140,47 @@ impl BlockChainClient for TestBlockChainClient {
 				}
 			}
 		}
-		if number == self.numbers.len() {
-			self.difficulty = self.difficulty + header.difficulty;
-			self.last_hash = header.hash();
-			self.blocks.insert(header.hash(), b);
-			self.numbers.insert(number, header.hash());
+		let len = self.numbers.read().unwrap().len();
+		if number == len {
+			*self.difficulty.write().unwrap().deref_mut() += header.difficulty;
+			mem::replace(self.last_hash.write().unwrap().deref_mut(), h.clone());
+			self.blocks.write().unwrap().insert(h.clone(), b);
+			self.numbers.write().unwrap().insert(number, h.clone());
 			let mut parent_hash = header.parent_hash;
 			if number > 0 {
 				let mut n = number - 1;
-				while n > 0 && self.numbers[&n] != parent_hash {
-					*self.numbers.get_mut(&n).unwrap() = parent_hash.clone();
+				while n > 0 && self.numbers.read().unwrap()[&n] != parent_hash {
+					*self.numbers.write().unwrap().get_mut(&n).unwrap() = parent_hash.clone();
 					n -= 1;
-					parent_hash = Rlp::new(&self.blocks[&parent_hash]).val_at::<BlockHeader>(0).parent_hash;
+					parent_hash = Rlp::new(&self.blocks.read().unwrap()[&parent_hash]).val_at::<BlockHeader>(0).parent_hash;
 				}
 			}
 		}
 		else {
-			self.blocks.insert(header.hash(), b.to_vec());
+			self.blocks.write().unwrap().insert(h.clone(), b.to_vec());
 		}
-		Ok(())
+		Ok(h)
 	}
 
-	fn queue_status(&self) -> BlockQueueStatus {
-		BlockQueueStatus {
+	fn queue_info(&self) -> BlockQueueInfo {
+		BlockQueueInfo {
 			full: false,
+			verified_queue_size: 0,
+			unverified_queue_size: 0,
+			verifying_queue_size: 0,
 		}
 	}
 
-	fn clear_queue(&mut self) {
+	fn clear_queue(&self) {
 	}
 
 	fn chain_info(&self) -> BlockChainInfo {
 		BlockChainInfo {
-			total_difficulty: self.difficulty,
-			pending_total_difficulty: self.difficulty,
+			total_difficulty: *self.difficulty.read().unwrap(),
+			pending_total_difficulty: *self.difficulty.read().unwrap(),
 			genesis_hash: self.genesis_hash.clone(),
-			best_block_hash: self.last_hash.clone(),
-			best_block_number: self.blocks.len() as BlockNumber - 1,
+			best_block_hash: self.last_hash.read().unwrap().clone(),
+			best_block_number: self.blocks.read().unwrap().len() as BlockNumber - 1,
 		}
 	}
 }
@@ -208,7 +223,7 @@ impl<'p> SyncIo for TestIo<'p> {
 		Ok(())
 	}
 
-	fn chain<'a>(&'a mut self) -> &'a mut BlockChainClient {
+	fn chain(&self) -> &BlockChainClient {
 		self.chain
 	}
 }
@@ -265,17 +280,14 @@ impl TestNet {
 
 	pub fn sync_step(&mut self) {
 		for peer in 0..self.peers.len() {
-			match self.peers[peer].queue.pop_front() {
-				Some(packet) => {
-					let mut p = self.peers.get_mut(packet.recipient).unwrap();
-					trace!("--- {} -> {} ---", peer, packet.recipient);
-					p.sync.on_packet(&mut TestIo::new(&mut p.chain, &mut p.queue, Some(peer as PeerId)), peer as PeerId, packet.packet_id, &packet.data);
-					trace!("----------------");
-				},
-				None => {}
+			if let Some(packet) = self.peers[peer].queue.pop_front() {
+				let mut p = self.peers.get_mut(packet.recipient).unwrap();
+				trace!("--- {} -> {} ---", peer, packet.recipient);
+				p.sync.on_packet(&mut TestIo::new(&mut p.chain, &mut p.queue, Some(peer as PeerId)), peer as PeerId, packet.packet_id, &packet.data);
+				trace!("----------------");
 			}
 			let mut p = self.peers.get_mut(peer).unwrap();
-			p.sync.maintain_sync(&mut TestIo::new(&mut p.chain, &mut p.queue, None));
+			p.sync._maintain_sync(&mut TestIo::new(&mut p.chain, &mut p.queue, None));
 		}
 	}
 
@@ -300,7 +312,7 @@ fn full_sync_two_peers() {
 	net.peer_mut(2).chain.add_blocks(1000, false);
 	net.sync();
 	assert!(net.peer(0).chain.block_at(1000).is_some());
-	assert_eq!(net.peer(0).chain.blocks, net.peer(1).chain.blocks);
+	assert_eq!(net.peer(0).chain.blocks.read().unwrap().deref(), net.peer(1).chain.blocks.read().unwrap().deref());
 }
 
 #[test]
@@ -313,7 +325,7 @@ fn full_sync_empty_blocks() {
 	}
 	net.sync();
 	assert!(net.peer(0).chain.block_at(1000).is_some());
-	assert_eq!(net.peer(0).chain.blocks, net.peer(1).chain.blocks);
+	assert_eq!(net.peer(0).chain.blocks.read().unwrap().deref(), net.peer(1).chain.blocks.read().unwrap().deref());
 }
 
 #[test]
@@ -329,9 +341,9 @@ fn forked_sync() {
 	net.peer_mut(1).chain.add_blocks(100, false); //fork between 1 and 2
 	net.peer_mut(2).chain.add_blocks(10, true);
 	// peer 1 has the best chain of 601 blocks
-	let peer1_chain = net.peer(1).chain.numbers.clone();
+	let peer1_chain = net.peer(1).chain.numbers.read().unwrap().clone();
 	net.sync();
-	assert_eq!(net.peer(0).chain.numbers, peer1_chain);
-	assert_eq!(net.peer(1).chain.numbers, peer1_chain);
-	assert_eq!(net.peer(2).chain.numbers, peer1_chain);
+	assert_eq!(net.peer(0).chain.numbers.read().unwrap().deref(), &peer1_chain);
+	assert_eq!(net.peer(1).chain.numbers.read().unwrap().deref(), &peer1_chain);
+	assert_eq!(net.peer(2).chain.numbers.read().unwrap().deref(), &peer1_chain);
 }

src/tests/chain.rs

@@ -0,0 +1,82 @@
+use super::test_common::*;
+use client::{BlockChainClient,Client};
+use pod_state::*;
+use block::Block;
+use ethereum;
+use super::helpers::*;
+
+pub enum ChainEra {
+	Frontier,
+	Homestead,
+}
+
+pub fn json_chain_test(json_data: &[u8], era: ChainEra) -> Vec<String> {
+	let json = Json::from_str(::std::str::from_utf8(json_data).unwrap()).expect("Json is invalid");
+	let mut failed = Vec::new();
+
+	for (name, test) in json.as_object().unwrap() {
+		let mut fail = false;
+		{
+			let mut fail_unless = |cond: bool| if !cond && !fail {
+				failed.push(name.clone());
+				flush(format!("FAIL\n"));
+				fail = true;
+				true
+			} else {false};
+
+			flush(format!("   - {}...", name));
+
+			let blocks: Vec<(Bytes, bool)> = test["blocks"].as_array().unwrap().iter().map(|e| (xjson!(&e["rlp"]), e.find("blockHeader").is_some())).collect();
+			let mut spec = match era {
+				ChainEra::Frontier => ethereum::new_frontier_test(),
+				ChainEra::Homestead => ethereum::new_homestead_test(),
+			};
+			let s = PodState::from_json(test.find("pre").unwrap());
+			spec.set_genesis_state(s);
+			spec.overwrite_genesis(test.find("genesisBlockHeader").unwrap());
+			assert!(spec.is_state_root_valid());
+
+			let temp = RandomTempPath::new();
+			{
+				let client = Client::new(spec, temp.as_path(), IoChannel::disconnected()).unwrap();
+				for (b, is_valid) in blocks.into_iter() {
+					if Block::is_good(&b) {
+						let _ = client.import_block(b.clone());
+					}
+					client.flush_queue();
+					let imported_ok = client.import_verified_blocks(&IoChannel::disconnected()) > 0;
+					assert_eq!(imported_ok, is_valid);
+				}
+				fail_unless(client.chain_info().best_block_hash == H256::from_json(&test["lastblockhash"]));
+			}
+		}
+		if !fail {
+			flush(format!("ok\n"));
+		}
+	}
+	println!("!!! {:?} tests from failed.", failed.len());
+	failed
+}
+
+fn do_json_test(json_data: &[u8]) -> Vec<String> {
+	json_chain_test(json_data, ChainEra::Frontier)
+}
+
+declare_test!{BlockchainTests_bcBlockGasLimitTest, "BlockchainTests/bcBlockGasLimitTest"}
+declare_test!{BlockchainTests_bcForkBlockTest, "BlockchainTests/bcForkBlockTest"}
+declare_test!{BlockchainTests_bcForkStressTest, "BlockchainTests/bcForkStressTest"}
+declare_test!{BlockchainTests_bcForkUncle, "BlockchainTests/bcForkUncle"}
+declare_test!{BlockchainTests_bcGasPricerTest, "BlockchainTests/bcGasPricerTest"}
+declare_test!{BlockchainTests_bcInvalidHeaderTest, "BlockchainTests/bcInvalidHeaderTest"}
+declare_test!{BlockchainTests_bcInvalidRLPTest, "BlockchainTests/bcInvalidRLPTest"}
+declare_test!{BlockchainTests_bcMultiChainTest, "BlockchainTests/bcMultiChainTest"}
+declare_test!{BlockchainTests_bcRPC_API_Test, "BlockchainTests/bcRPC_API_Test"}
+declare_test!{BlockchainTests_bcStateTest, "BlockchainTests/bcStateTest"}
+declare_test!{BlockchainTests_bcTotalDifficultyTest, "BlockchainTests/bcTotalDifficultyTest"}
+declare_test!{BlockchainTests_bcUncleHeaderValiditiy, "BlockchainTests/bcUncleHeaderValiditiy"}
+declare_test!{BlockchainTests_bcUncleTest, "BlockchainTests/bcUncleTest"}
+declare_test!{BlockchainTests_bcValidBlockTest, "BlockchainTests/bcValidBlockTest"}
+declare_test!{BlockchainTests_bcWalletTest, "BlockchainTests/bcWalletTest"}
+
+declare_test!{BlockchainTests_RandomTests_bl10251623GO, "BlockchainTests/RandomTests/bl10251623GO"}
+declare_test!{BlockchainTests_RandomTests_bl201507071825GO, "BlockchainTests/RandomTests/bl201507071825GO"}

src/tests/client.rs

@@ -0,0 +1,117 @@
+use client::{BlockChainClient,Client};
+use super::test_common::*;
+use super::helpers::*;
+
+fn get_good_dummy_block() -> Bytes {
+	let mut block_header = Header::new();
+	let test_spec = get_test_spec();
+	let test_engine = test_spec.to_engine().unwrap();
+	block_header.gas_limit = decode(test_engine.spec().engine_params.get("minGasLimit").unwrap());
+	block_header.difficulty = decode(test_engine.spec().engine_params.get("minimumDifficulty").unwrap());
+	block_header.timestamp = 40;
+	block_header.number = 1;
+	block_header.parent_hash = test_engine.spec().genesis_header().hash();
+	block_header.state_root = test_engine.spec().genesis_header().state_root;
+
+	create_test_block(&block_header)
+}
+
+fn get_bad_state_dummy_block() -> Bytes {
+	let mut block_header = Header::new();
+	let test_spec = get_test_spec();
+	let test_engine = test_spec.to_engine().unwrap();
+	block_header.gas_limit = decode(test_engine.spec().engine_params.get("minGasLimit").unwrap());
+	block_header.difficulty = decode(test_engine.spec().engine_params.get("minimumDifficulty").unwrap());
+	block_header.timestamp = 40;
+	block_header.number = 1;
+	block_header.parent_hash = test_engine.spec().genesis_header().hash();
+	block_header.state_root = x!(0xbad);
+
+	create_test_block(&block_header)
+}
+
+
+fn get_test_client_with_blocks(blocks: Vec<Bytes>) -> Arc<Client> {
+	let dir = RandomTempPath::new();
+	let client = Client::new(get_test_spec(), dir.as_path(), IoChannel::disconnected()).unwrap();
+	for block in &blocks {
+		if let Err(_) = client.import_block(block.clone()) {
+			panic!("panic importing block which is well-formed");
+		}
+	}
+	client.flush_queue();
+	client.import_verified_blocks(&IoChannel::disconnected());
+	client
+}
+
+
+#[test]
+fn created() {
+	let dir = RandomTempPath::new();
+	let client_result = Client::new(get_test_spec(), dir.as_path(), IoChannel::disconnected());
+	assert!(client_result.is_ok());
+}
+
+#[test]
+fn imports_from_empty() {
+	let dir = RandomTempPath::new();
+	let client = Client::new(get_test_spec(), dir.as_path(), IoChannel::disconnected()).unwrap();
+	client.import_verified_blocks(&IoChannel::disconnected());
+	client.flush_queue();
+}
+
+#[test]
+fn imports_good_block() {
+	let dir = RandomTempPath::new();
+	let client = Client::new(get_test_spec(), dir.as_path(), IoChannel::disconnected()).unwrap();
+	let good_block = get_good_dummy_block();
+	if let Err(_) = client.import_block(good_block) {
+		panic!("error importing block being good by definition");
+	}
+	client.flush_queue();
+	client.import_verified_blocks(&IoChannel::disconnected());
+
+	let block = client.block_header_at(1).unwrap();
+	assert!(!block.is_empty());
+}
+
+#[test]
+fn query_none_block() {
+	let dir = RandomTempPath::new();
+	let client = Client::new(get_test_spec(), dir.as_path(), IoChannel::disconnected()).unwrap();
+
+    let non_existant = client.block_header_at(188);
+	assert!(non_existant.is_none());
+}
+
+#[test]
+fn query_bad_block() {
+	let client = get_test_client_with_blocks(vec![get_bad_state_dummy_block()]);
+	let bad_block:Option<Bytes> = client.block_header_at(1);
+
+	assert!(bad_block.is_none());
+}
+
+#[test]
+fn returns_chain_info() {
+	let dummy_block = get_good_dummy_block();
+	let client = get_test_client_with_blocks(vec![dummy_block.clone()]);
+	let block = BlockView::new(&dummy_block);
+	let info = client.chain_info();
+	assert_eq!(info.best_block_hash, block.header().hash());
+}
+
+#[test]
+fn imports_block_sequence() {
+	let client = generate_dummy_client(6);
+	let block = client.block_header_at(5).unwrap();
+
+	assert!(!block.is_empty());
+}
+
+#[test]
+fn can_collect_garbage() {
+	let client = generate_dummy_client(100);
+	client.tick();
+	assert!(client.cache_info().blocks < 100 * 1024);
+}

src/tests/executive.rs

@@ -101,8 +101,9 @@ impl<'a> Ext for TestExt<'a> {
 
 	fn call(&mut self, 
 			gas: &U256, 
+			_sender_address: &Address, 
 			receive_address: &Address, 
-			value: &U256, 
+			value: Option<U256>,
 			data: &[u8], 
 			_code_address: &Address, 
 			_output: &mut [u8]) -> MessageCallResult {
@@ -110,7 +111,7 @@ impl<'a> Ext for TestExt<'a> {
 			data: data.to_vec(),
 			destination: Some(receive_address.clone()),
 			gas_limit: *gas,
-			value: *value
+			value: value.unwrap()
 		});
 		MessageCallResult::Success(*gas)
 	}
@@ -168,7 +169,7 @@ fn do_json_test_for(vm: &VMType, json_data: &[u8]) -> Vec<String> {
 		let mut fail = false;
 		//let mut fail_unless = |cond: bool| if !cond && !fail { failed.push(name.to_string()); fail = true };
 		let mut fail_unless = |cond: bool, s: &str | if !cond && !fail { 
-			failed.push(format!("[{}] {}: {}", vm, name.to_string(), s)); 
+			failed.push(format!("[{}] {}: {}", vm, name, s)); 
 			fail = true 
 		};
 	
@@ -187,20 +188,14 @@ fn do_json_test_for(vm: &VMType, json_data: &[u8]) -> Vec<String> {
 			BTreeMap::from_json(&s["storage"]).into_iter().foreach(|(k, v)| state.set_storage(&address, k, v));
 		});
 
-		let mut info = EnvInfo::new();
-
-		test.find("env").map(|env| {
-			info.author = xjson!(&env["currentCoinbase"]);
-			info.difficulty = xjson!(&env["currentDifficulty"]);
-			info.gas_limit = xjson!(&env["currentGasLimit"]);
-			info.number = xjson!(&env["currentNumber"]);
-			info.timestamp = xjson!(&env["currentTimestamp"]);
-		});
+		let info = test.find("env").map(|env| {
+			EnvInfo::from_json(env)
+		}).unwrap_or_default();
 
 		let engine = TestEngine::new(1, vm.clone());
 
 		// params
-		let mut params = ActionParams::new();
+		let mut params = ActionParams::default();
 		test.find("exec").map(|exec| {
 			params.address = xjson!(&exec["address"]);
 			params.sender = xjson!(&exec["caller"]);
@@ -209,7 +204,7 @@ fn do_json_test_for(vm: &VMType, json_data: &[u8]) -> Vec<String> {
 			params.data = xjson!(&exec["data"]);
 			params.gas = xjson!(&exec["gas"]);
 			params.gas_price = xjson!(&exec["gasPrice"]);
-			params.value = xjson!(&exec["value"]);
+			params.value = ActionValue::Transfer(xjson!(&exec["value"]));
 		});
 
 		let out_of_gas = test.find("callcreates").map(|_calls| {
@@ -245,7 +240,7 @@ fn do_json_test_for(vm: &VMType, json_data: &[u8]) -> Vec<String> {
 				test.find("post").map(|pre| for (addr, s) in pre.as_object().unwrap() {
 					let address = Address::from(addr.as_ref());
 
-					fail_unless(state.code(&address).unwrap_or(vec![]) == Bytes::from_json(&s["code"]), "code is incorrect");
+					fail_unless(state.code(&address).unwrap_or_else(|| vec![]) == Bytes::from_json(&s["code"]), "code is incorrect");
 					fail_unless(state.balance(&address) == xjson!(&s["balance"]), "balance is incorrect");
 					fail_unless(state.nonce(&address) == xjson!(&s["nonce"]), "nonce is incorrect");
 					BTreeMap::from_json(&s["storage"]).iter().foreach(|(k, v)| fail_unless(&state.storage_at(&address, &k) == v, "storage is incorrect"));
@@ -266,7 +261,7 @@ fn do_json_test_for(vm: &VMType, json_data: &[u8]) -> Vec<String> {
 	}
 
 
-	for f in failed.iter() {
+	for f in &failed {
 		println!("FAILED: {:?}", f);
 	}
 
@@ -276,12 +271,11 @@ fn do_json_test_for(vm: &VMType, json_data: &[u8]) -> Vec<String> {
 
 declare_test!{ExecutiveTests_vmArithmeticTest, "VMTests/vmArithmeticTest"}
 declare_test!{ExecutiveTests_vmBitwiseLogicOperationTest, "VMTests/vmBitwiseLogicOperationTest"}
-// this one crashes with some vm internal error. Separately they pass.
-declare_test_ignore!{ExecutiveTests_vmBlockInfoTest, "VMTests/vmBlockInfoTest"}
+declare_test!{ExecutiveTests_vmBlockInfoTest, "VMTests/vmBlockInfoTest"}
+ // TODO [todr] Fails with Signal 11 when using JIT
 declare_test!{ExecutiveTests_vmEnvironmentalInfoTest, "VMTests/vmEnvironmentalInfoTest"}
 declare_test!{ExecutiveTests_vmIOandFlowOperationsTest, "VMTests/vmIOandFlowOperationsTest"}
-// this one take way too long.
-declare_test_ignore!{ExecutiveTests_vmInputLimits, "VMTests/vmInputLimits"}
+declare_test!{heavy => ExecutiveTests_vmInputLimits, "VMTests/vmInputLimits"}
 declare_test!{ExecutiveTests_vmLogTest, "VMTests/vmLogTest"}
 declare_test!{ExecutiveTests_vmPerformanceTest, "VMTests/vmPerformanceTest"}
 declare_test!{ExecutiveTests_vmPushDupSwapTest, "VMTests/vmPushDupSwapTest"}

src/tests/helpers.rs

@@ -0,0 +1,80 @@
+use client::{BlockChainClient,Client};
+use std::env;
+use super::test_common::*;
+use std::path::PathBuf;
+use spec::*;
+use std::fs::{remove_dir_all};
+
+
+pub struct RandomTempPath {
+	path: PathBuf
+}
+
+impl RandomTempPath {
+	pub fn new() -> RandomTempPath {
+		let mut dir = env::temp_dir();
+		dir.push(H32::random().hex());
+		RandomTempPath {
+			path: dir.clone()
+		}
+	}
+
+	pub fn as_path(&self) -> &PathBuf {
+		&self.path
+	}
+}
+
+impl Drop for RandomTempPath {
+	fn drop(&mut self) {
+		if let Err(e) = remove_dir_all(self.as_path()) {
+			panic!("failed to remove temp directory, probably something failed to destroyed ({})", e);
+		}
+	}
+}
+
+pub fn get_test_spec() -> Spec {
+	Spec::new_test()
+}
+
+pub fn create_test_block(header: &Header) -> Bytes {
+	let mut rlp = RlpStream::new_list(3);
+	rlp.append(header);
+	rlp.append_raw(&rlp::EMPTY_LIST_RLP, 1);
+	rlp.append_raw(&rlp::EMPTY_LIST_RLP, 1);
+	rlp.out()
+}
+
+pub fn generate_dummy_client(block_number: usize) -> Arc<Client> {
+	let dir = RandomTempPath::new();
+
+	let client = Client::new(get_test_spec(), dir.as_path(), IoChannel::disconnected()).unwrap();
+	let test_spec = get_test_spec();
+	let test_engine = test_spec.to_engine().unwrap();
+	let state_root = test_engine.spec().genesis_header().state_root;
+	let mut rolling_hash = test_engine.spec().genesis_header().hash();
+	let mut rolling_block_number = 1;
+	let mut rolling_timestamp = 40;
+
+	for _ in 0..block_number {
+		let mut header = Header::new();
+
+		header.gas_limit = decode(test_engine.spec().engine_params.get("minGasLimit").unwrap());
+		header.difficulty = decode(test_engine.spec().engine_params.get("minimumDifficulty").unwrap());
+		header.timestamp = rolling_timestamp;
+		header.number = rolling_block_number;
+		header.parent_hash = rolling_hash;
+		header.state_root = state_root.clone();
+
+		rolling_hash = header.hash();
+		rolling_block_number = rolling_block_number + 1;
+		rolling_timestamp = rolling_timestamp + 10;
+
+		if let Err(_) = client.import_block(create_test_block(&header)) {
+			panic!("error importing block which is valid by definition");
+		}
+
+	}
+	client.flush_queue();
+	client.import_verified_blocks(&IoChannel::disconnected());
+	client
+}

src/tests/homestead_chain.rs

@@ -0,0 +1,20 @@
+use super::test_common::*;
+use super::chain::{ChainEra, json_chain_test};
+
+fn do_json_test(json_data: &[u8]) -> Vec<String> {
+	json_chain_test(json_data, ChainEra::Homestead)
+}
+
+declare_test!{BlockchainTests_Homestead_bcBlockGasLimitTest, "BlockchainTests/Homestead/bcBlockGasLimitTest"}
+declare_test!{BlockchainTests_Homestead_bcForkStressTest, "BlockchainTests/Homestead/bcForkStressTest"}
+declare_test!{BlockchainTests_Homestead_bcGasPricerTest, "BlockchainTests/Homestead/bcGasPricerTest"}
+declare_test!{BlockchainTests_Homestead_bcInvalidHeaderTest, "BlockchainTests/Homestead/bcInvalidHeaderTest"}
+declare_test!{BlockchainTests_Homestead_bcInvalidRLPTest, "BlockchainTests/Homestead/bcInvalidRLPTest"}
+declare_test!{BlockchainTests_Homestead_bcMultiChainTest, "BlockchainTests/Homestead/bcMultiChainTest"}
+declare_test!{BlockchainTests_Homestead_bcRPC_API_Test, "BlockchainTests/Homestead/bcRPC_API_Test"}
+declare_test!{BlockchainTests_Homestead_bcStateTest, "BlockchainTests/Homestead/bcStateTest"}
+declare_test!{BlockchainTests_Homestead_bcTotalDifficultyTest, "BlockchainTests/Homestead/bcTotalDifficultyTest"}
+declare_test!{BlockchainTests_Homestead_bcUncleHeaderValiditiy, "BlockchainTests/Homestead/bcUncleHeaderValiditiy"}
+declare_test!{BlockchainTests_Homestead_bcUncleTest, "BlockchainTests/Homestead/bcUncleTest"}
+declare_test!{BlockchainTests_Homestead_bcValidBlockTest, "BlockchainTests/Homestead/bcValidBlockTest"}
+declare_test!{BlockchainTests_Homestead_bcWalletTest, "BlockchainTests/Homestead/bcWalletTest"}

src/tests/mod.rs

@@ -4,3 +4,7 @@ mod test_common;
 mod transaction;
 mod executive;
 mod state;
+mod client;
+mod chain;
+pub mod helpers;
+mod homestead_chain;

src/tests/state.rs

@@ -15,7 +15,7 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 		let mut fail = false;
 		{
 			let mut fail_unless = |cond: bool| if !cond && !fail {
-				failed.push(name.to_string());
+				failed.push(name.clone());
 				flush(format!("FAIL\n"));
 				fail = true;
 				true
@@ -73,20 +73,20 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 
 declare_test!{StateTests_stBlockHashTest, "StateTests/stBlockHashTest"}
 declare_test!{StateTests_stCallCodes, "StateTests/stCallCodes"}
-declare_test_ignore!{StateTests_stCallCreateCallCodeTest, "StateTests/stCallCreateCallCodeTest"}	//<< Out of stack
-declare_test!{StateTests_stDelegatecallTest, "StateTests/stDelegatecallTest"}						//<< FAIL - gas too high
+declare_test!{StateTests_stCallCreateCallCodeTest, "StateTests/stCallCreateCallCodeTest"}
+declare_test!{StateTests_stDelegatecallTest, "StateTests/stDelegatecallTest"}
 declare_test!{StateTests_stExample, "StateTests/stExample"}
 declare_test!{StateTests_stInitCodeTest, "StateTests/stInitCodeTest"}
 declare_test!{StateTests_stLogTests, "StateTests/stLogTests"}
-declare_test!{StateTests_stMemoryStressTest, "StateTests/stMemoryStressTest"}
-declare_test!{StateTests_stMemoryTest, "StateTests/stMemoryTest"}
+declare_test!{heavy => StateTests_stMemoryStressTest, "StateTests/stMemoryStressTest"}
+declare_test!{heavy => StateTests_stMemoryTest, "StateTests/stMemoryTest"}
 declare_test!{StateTests_stPreCompiledContracts, "StateTests/stPreCompiledContracts"}
-declare_test_ignore!{StateTests_stQuadraticComplexityTest, "StateTests/stQuadraticComplexityTest"}	//<< Too long
-declare_test_ignore!{StateTests_stRecursiveCreate, "StateTests/stRecursiveCreate"}					//<< Out of stack 
+declare_test!{heavy => StateTests_stQuadraticComplexityTest, "StateTests/stQuadraticComplexityTest"}
+declare_test!{StateTests_stRecursiveCreate, "StateTests/stRecursiveCreate"}
 declare_test!{StateTests_stRefundTest, "StateTests/stRefundTest"}
 declare_test!{StateTests_stSolidityTest, "StateTests/stSolidityTest"}
-declare_test_ignore!{StateTests_stSpecialTest, "StateTests/stSpecialTest"}							//<< Signal 11
-declare_test_ignore!{StateTests_stSystemOperationsTest, "StateTests/stSystemOperationsTest"}		//<< Signal 11
+declare_test!{StateTests_stSpecialTest, "StateTests/stSpecialTest"}
+declare_test!{StateTests_stSystemOperationsTest, "StateTests/stSystemOperationsTest"}
 declare_test!{StateTests_stTransactionTest, "StateTests/stTransactionTest"}
 declare_test!{StateTests_stTransitionTest, "StateTests/stTransitionTest"}
 declare_test!{StateTests_stWalletTest, "StateTests/stWalletTest"}

src/tests/test_common.rs

@@ -1,24 +1,34 @@
 pub use common::*;
 
+macro_rules! test {
+	($name: expr) => {
+		assert!(do_json_test(include_bytes!(concat!("../../res/ethereum/tests/", $name, ".json"))).is_empty());
+	}
+}
+
 #[macro_export]
 macro_rules! declare_test {
-	($id: ident, $name: expr) => {
-		#[test]
-		#[allow(non_snake_case)]
-		fn $id() {
-			assert!(do_json_test(include_bytes!(concat!("../../res/ethereum/tests/", $name, ".json"))).len() == 0);
-		}
-	};
-}
-
-#[macro_export]
-macro_rules! declare_test_ignore {
-	($id: ident, $name: expr) => {
-		#[test]
+	(ignore => $id: ident, $name: expr) => {
 		#[ignore]
+		#[test]
 		#[allow(non_snake_case)]
 		fn $id() {
-			assert!(do_json_test(include_bytes!(concat!("../../res/ethereum/tests/", $name, ".json"))).len() == 0);
+			test!($name);
 		}
 	};
+	(heavy => $id: ident, $name: expr) => {
+		#[cfg(feature = "test-heavy")]
+		#[test]
+		#[allow(non_snake_case)]
+		fn $id() {
+			test!($name);
+		}
+	};
+	($id: ident, $name: expr) => {
+		#[test]
+		#[allow(non_snake_case)]
+		fn $id() {
+			test!($name);
+		}
+	}
 }

src/tests/transaction.rs

@@ -9,13 +9,13 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 	let ot = RefCell::new(Transaction::new());
 	for (name, test) in json.as_object().unwrap() {
 		let mut fail = false;
-		let mut fail_unless = |cond: bool| if !cond && !fail { failed.push(name.to_string()); println!("Transaction: {:?}", ot.borrow()); fail = true };
+		let mut fail_unless = |cond: bool| if !cond && !fail { failed.push(name.clone()); println!("Transaction: {:?}", ot.borrow()); fail = true };
 		let schedule = match test.find("blocknumber")
 			.and_then(|j| j.as_string())
 			.and_then(|s| BlockNumber::from_str(s).ok())
 			.unwrap_or(0) { x if x < 900000 => &old_schedule, _ => &new_schedule };
 		let rlp = Bytes::from_json(&test["rlp"]);
-		let res = UntrustedRlp::new(&rlp).as_val().map_err(|e| From::from(e)).and_then(|t: Transaction| t.validate(schedule, schedule.have_delegate_call));
+		let res = UntrustedRlp::new(&rlp).as_val().map_err(From::from).and_then(|t: Transaction| t.validate(schedule, schedule.have_delegate_call));
 		fail_unless(test.find("transaction").is_none() == res.is_err());
 		if let (Some(&Json::Object(ref tx)), Some(&Json::String(ref expect_sender))) = (test.find("transaction"), test.find("sender")) {
 			let t = res.unwrap();
@@ -30,11 +30,11 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 				fail_unless(to == &xjson!(&tx["to"]));
 			} else {
 				*ot.borrow_mut() = t.clone();
-				fail_unless(Bytes::from_json(&tx["to"]).len() == 0);
+				fail_unless(Bytes::from_json(&tx["to"]).is_empty());
 			}
 		}
 	}
-	for f in failed.iter() {
+	for f in &failed {
 		println!("FAILED: {:?}", f);
 	}
 	failed
@@ -65,14 +65,14 @@ declare_test!{TransactionTests/ttTransactionTest}
 declare_test!{TransactionTests/tt10mbDataField}
 declare_test!{TransactionTests/ttWrongRLPTransaction}
 declare_test!{TransactionTests/Homestead/ttTransactionTest}
-declare_test!{TransactionTests/Homestead/tt10mbDataField}
+declare_test!{heavy => TransactionTests/Homestead/tt10mbDataField}
 declare_test!{TransactionTests/Homestead/ttWrongRLPTransaction}
 declare_test!{TransactionTests/RandomTests/tr201506052141PYTHON}*/
 
 declare_test!{TransactionTests_ttTransactionTest, "TransactionTests/ttTransactionTest"}
-declare_test_ignore!{TransactionTests_tt10mbDataField, "TransactionTests/tt10mbDataField"}
+declare_test!{heavy => TransactionTests_tt10mbDataField, "TransactionTests/tt10mbDataField"}
 declare_test!{TransactionTests_ttWrongRLPTransaction, "TransactionTests/ttWrongRLPTransaction"}
 declare_test!{TransactionTests_Homestead_ttTransactionTest, "TransactionTests/Homestead/ttTransactionTest"}
-declare_test_ignore!{TransactionTests_Homestead_tt10mbDataField, "TransactionTests/Homestead/tt10mbDataField"}
+declare_test!{heavy => TransactionTests_Homestead_tt10mbDataField, "TransactionTests/Homestead/tt10mbDataField"}
 declare_test!{TransactionTests_Homestead_ttWrongRLPTransaction, "TransactionTests/Homestead/ttWrongRLPTransaction"}
 declare_test!{TransactionTests_RandomTests_tr201506052141PYTHON, "TransactionTests/RandomTests/tr201506052141PYTHON"}

src/transaction.rs

@@ -3,7 +3,7 @@ use basic_types::*;
 use error::*;
 use evm::Schedule;
 
-#[derive(Debug,Clone)]
+#[derive(Debug, Clone)]
 /// TODO [Gav Wood] Please document me
 pub enum Action {
 	/// TODO [Gav Wood] Please document me
@@ -12,9 +12,13 @@ pub enum Action {
 	Call(Address),
 }
 
+impl Default for Action {
+	fn default() -> Action { Action::Create }
+}
+
 /// A set of information describing an externally-originating message call
 /// or contract creation operation.
-#[derive(Debug,Clone)]
+#[derive(Default, Debug, Clone)]
 pub struct Transaction {
 	/// TODO [debris] Please document me
 	pub nonce: U256,
@@ -117,9 +121,8 @@ impl Transaction {
 		};
 		s.append(&self.value);
 		s.append(&self.data);
-		match with_seal {
-			Seal::With => { s.append(&(self.v as u16)).append(&self.r).append(&self.s); },
-			_ => {}
+		if let Seal::With = with_seal {
+			s.append(&(self.v as u16)).append(&self.r).append(&self.s);
 		}
 	}
 
@@ -138,7 +141,7 @@ impl FromJson for Transaction {
 			gas_price: xjson!(&json["gasPrice"]),
 			gas: xjson!(&json["gasLimit"]),
 			action: match Bytes::from_json(&json["to"]) {
-				ref x if x.len() == 0 => Action::Create,
+				ref x if x.is_empty() => Action::Create,
 				ref x => Action::Call(Address::from_slice(x)),
 			},
 			value: xjson!(&json["value"]),
@@ -303,4 +306,4 @@ fn signing() {
 	let key = KeyPair::create().unwrap();
 	let t = Transaction::new_create(U256::from(42u64), b"Hello!".to_vec(), U256::from(3000u64), U256::from(50_000u64), U256::from(1u64)).signed(&key.secret());
 	assert_eq!(Address::from(key.public().sha3()), t.sender().unwrap());
-}
+}

src/verification.rs

@@ -64,7 +64,7 @@ pub fn verify_block_unordered(header: Header, bytes: Bytes, engine: &Engine) ->
 /// Phase 3 verification. Check block information against parent and uncles.
 pub fn verify_block_family<BC>(header: &Header, bytes: &[u8], engine: &Engine, bc: &BC) -> Result<(), Error> where BC: BlockProvider {
 	// TODO: verify timestamp
-	let parent = try!(bc.block_header(&header.parent_hash).ok_or::<Error>(From::from(BlockError::UnknownParent(header.parent_hash.clone()))));
+	let parent = try!(bc.block_header(&header.parent_hash).ok_or_else(|| Error::from(BlockError::UnknownParent(header.parent_hash.clone()))));
 	try!(verify_parent(&header, &parent));
 	try!(engine.verify_block_family(&header, &parent, Some(bytes)));
 
@@ -122,7 +122,7 @@ pub fn verify_block_family<BC>(header: &Header, bytes: &[u8], engine: &Engine, b
 			// cB.p^7	-------------/
 			// cB.p^8
 			let mut expected_uncle_parent = header.parent_hash.clone();
-			let uncle_parent = try!(bc.block_header(&uncle.parent_hash).ok_or::<Error>(From::from(BlockError::UnknownUncleParent(uncle.parent_hash.clone()))));
+			let uncle_parent = try!(bc.block_header(&uncle.parent_hash).ok_or_else(|| Error::from(BlockError::UnknownUncleParent(uncle.parent_hash.clone()))));
 			for _ in 0..depth {
 				match bc.block_details(&expected_uncle_parent) {
 					Some(details) => { 
@@ -162,7 +162,7 @@ pub fn verify_block_final(expected: &Header, got: &Header) -> Result<(), Error>
 /// Check basic header parameters.
 fn verify_header(header: &Header, engine: &Engine) -> Result<(), Error> {
 	if header.number >= From::from(BlockNumber::max_value()) {
-		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: Some(From::from(BlockNumber::max_value())), min: None, found: header.number })))
+		return Err(From::from(BlockError::RidiculousNumber(OutOfBounds { max: Some(From::from(BlockNumber::max_value())), min: None, found: header.number })))
 	}
 	if header.gas_used > header.gas_limit {
 		return Err(From::from(BlockError::TooMuchGasUsed(OutOfBounds { max: Some(header.gas_limit), min: None, found: header.gas_used })));
@@ -186,8 +186,8 @@ fn verify_parent(header: &Header, parent: &Header) -> Result<(), Error> {
 	if header.timestamp <= parent.timestamp {
 		return Err(From::from(BlockError::InvalidTimestamp(OutOfBounds { max: None, min: Some(parent.timestamp + 1), found: header.timestamp })))
 	}
-	if header.number <= parent.number {
-		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: None, min: Some(parent.number + 1), found: header.number })));
+	if header.number != parent.number + 1 {
+		return Err(From::from(BlockError::InvalidNumber(Mismatch { expected: parent.number + 1, found: header.number })));
 	}
 	Ok(())
 }
@@ -284,7 +284,7 @@ mod tests {
 
 		/// Get raw block data
 		fn block(&self, hash: &H256) -> Option<Bytes> {
-			self.blocks.get(hash).map(|b| b.clone())
+			self.blocks.get(hash).cloned()
 		}
 
 		/// Get the familial details concerning a block.
@@ -302,7 +302,7 @@ mod tests {
 
 		/// Get the hash of given block's number.
 		fn block_hash(&self, index: BlockNumber) -> Option<H256> {
-			self.numbers.get(&index).map(|h| h.clone())
+			self.numbers.get(&index).cloned()
 		}
 	}
 
@@ -400,7 +400,7 @@ mod tests {
 		header = good.clone();
 		header.number = BlockNumber::max_value();
 		check_fail(basic_test(&create_test_block(&header), engine.deref()),
-			InvalidNumber(OutOfBounds { max: Some(BlockNumber::max_value()), min: None, found: header.number }));
+			RidiculousNumber(OutOfBounds { max: Some(BlockNumber::max_value()), min: None, found: header.number }));
 
 		header = good.clone();
 		header.gas_used = header.gas_limit + From::from(1);
@@ -443,7 +443,7 @@ mod tests {
 		header = good.clone();
 		header.number = 9;
 		check_fail(family_test(&create_test_block_with_data(&header, &good_transactions, &good_uncles), engine.deref(), &bc),
-			InvalidNumber(OutOfBounds { max: None, min: Some(parent.number + 1), found: header.number }));
+			InvalidNumber(Mismatch { expected: parent.number + 1, found: header.number }));
 		
 		header = good.clone();
 		let mut bad_uncles = good_uncles.clone();

src/views.rs

@@ -141,7 +141,7 @@ impl<'a> BlockView<'a> {
 
 	/// Return List of transactions in given block.
 	pub fn transaction_views(&self) -> Vec<TransactionView> {
-		self.rlp.at(1).iter().map(|rlp| TransactionView::new_from_rlp(rlp)).collect()
+		self.rlp.at(1).iter().map(TransactionView::new_from_rlp).collect()
 	}
 
 	/// Return transaction hashes.
@@ -156,7 +156,7 @@ impl<'a> BlockView<'a> {
 
 	/// Return List of transactions in given block.
 	pub fn uncle_views(&self) -> Vec<HeaderView> {
-		self.rlp.at(2).iter().map(|rlp| HeaderView::new_from_rlp(rlp)).collect()
+		self.rlp.at(2).iter().map(HeaderView::new_from_rlp).collect()
 	}
 
 	/// Return list of uncle hashes of given block.

util/Cargo.toml

@@ -22,8 +22,11 @@ rust-crypto = "0.2.34"
 elastic-array = "0.4"
 heapsize = "0.2"
 itertools = "0.4"
+crossbeam = "0.2"
 slab = { git = "https://github.com/arkpar/slab.git" }
 sha3 = { path = "sha3" }
+serde = "0.6.7"
+clippy = "0.0.37"
 
 [dev-dependencies]
 json-tests = { path = "json-tests" }

util/src/bytes.rs

@@ -106,18 +106,18 @@ impl<'a> Deref for BytesRef<'a> {
 	type Target = [u8];
 
 	fn deref(&self) -> &[u8] {
-		match self {
-			&BytesRef::Flexible(ref bytes) => bytes,
-			&BytesRef::Fixed(ref bytes) => bytes
+		match *self {
+			BytesRef::Flexible(ref bytes) => bytes,
+			BytesRef::Fixed(ref bytes) => bytes
 		}
 	}
 }
 
 impl <'a> DerefMut for BytesRef<'a> {
 	fn deref_mut(&mut self) -> &mut [u8] {
-		match self {
-			&mut BytesRef::Flexible(ref mut bytes) => bytes,
-			&mut BytesRef::Fixed(ref mut bytes) => bytes
+		match *self {
+			BytesRef::Flexible(ref mut bytes) => bytes,
+			BytesRef::Fixed(ref mut bytes) => bytes
 		}
 	}
 }
@@ -273,7 +273,9 @@ pub enum FromBytesError {
 	/// TODO [debris] Please document me
 	DataIsTooShort,
 	/// TODO [debris] Please document me
-	DataIsTooLong
+	DataIsTooLong,
+	/// Integer-representation is non-canonically prefixed with zero byte(s).
+	ZeroPrefixedInt,
 }
 
 impl StdError for FromBytesError {
@@ -299,7 +301,7 @@ pub trait FromBytes: Sized {
 
 impl FromBytes for String {
 	fn from_bytes(bytes: &[u8]) -> FromBytesResult<String> {
-		Ok(::std::str::from_utf8(bytes).unwrap().to_string())
+		Ok(::std::str::from_utf8(bytes).unwrap().to_owned())
 	}
 }
 
@@ -310,6 +312,9 @@ macro_rules! impl_uint_from_bytes {
 				match bytes.len() {
 					0 => Ok(0),
 					l if l <= mem::size_of::<$to>() => {
+						if bytes[0] == 0 {
+							return Err(FromBytesError::ZeroPrefixedInt)
+						}
 						let mut res = 0 as $to;
 						for i in 0..l {
 							let shift = (l - 1 - i) * 8;
@@ -344,7 +349,9 @@ macro_rules! impl_uint_from_bytes {
 	($name: ident) => {
 		impl FromBytes for $name {
 			fn from_bytes(bytes: &[u8]) -> FromBytesResult<$name> {
-				if bytes.len() <= $name::SIZE {
+				if !bytes.is_empty() && bytes[0] == 0 {
+					Err(FromBytesError::ZeroPrefixedInt)
+				} else if bytes.len() <= $name::SIZE {
 					Ok($name::from(bytes))
 				} else {
 					Err(FromBytesError::DataIsTooLong)

util/src/chainfilter.rs

@@ -323,10 +323,9 @@ impl<'a, D> ChainFilter<'a, D> where D: FilterDataSource
 			let offset = level_size * index;
 
 			// go doooown!
-			match self.blocks(bloom, from_block, to_block, max_level, offset) {
-				Some(blocks) => result.extend(blocks),
-				None => ()
-			};
+			if let Some(blocks) = self.blocks(bloom, from_block, to_block, max_level, offset) {
+				result.extend(blocks);
+			}
 		}
 
 		result

util/src/hash.rs

@@ -8,6 +8,8 @@ use rand::os::OsRng;
 use bytes::{BytesConvertable,Populatable};
 use from_json::*;
 use uint::{Uint, U256};
+use rustc_serialize::hex::ToHex;
+use serde;
 
 /// Trait for a fixed-size byte array to be used as the output of hash functions.
 ///
@@ -41,6 +43,8 @@ pub trait FixedHash: Sized + BytesConvertable + Populatable + FromStr + Default
 	fn contains<'a>(&'a self, b: &'a Self) -> bool;
 	/// TODO [debris] Please document me
 	fn is_zero(&self) -> bool;
+	/// Return the lowest 8 bytes interpreted as a BigEndian integer.
+	fn low_u64(&self) -> u64;
 }
 
 fn clean_0x(s: &str) -> &str {
@@ -71,8 +75,8 @@ macro_rules! impl_hash {
 				&self.0
 			}
 		}
-		impl DerefMut for $from {
 
+		impl DerefMut for $from {
 			#[inline]
 			fn deref_mut(&mut self) -> &mut [u8] {
 				&mut self.0
@@ -190,6 +194,14 @@ macro_rules! impl_hash {
 			fn is_zero(&self) -> bool {
 				self.eq(&Self::new())
 			}
+
+			fn low_u64(&self) -> u64 {
+				let mut ret = 0u64;
+				for i in 0..min($size, 8) {
+					ret |= (self.0[$size - 1 - i] as u64) << (i * 8);
+				}
+				ret
+			}
 		}
 
 		impl FromStr for $from {
@@ -205,13 +217,48 @@ macro_rules! impl_hash {
 			}
 		}
 
+		impl serde::Serialize for $from {
+			fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error> 
+			where S: serde::Serializer {
+				let mut hex = "0x".to_owned();
+				hex.push_str(self.to_hex().as_ref());
+				serializer.visit_str(hex.as_ref())
+			}
+		}
+
+		impl serde::Deserialize for $from {
+			fn deserialize<D>(deserializer: &mut D) -> Result<$from, D::Error>
+			where D: serde::Deserializer {
+				struct HashVisitor;
+
+				impl serde::de::Visitor for HashVisitor {
+					type Value = $from;
+					
+					fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: serde::Error {
+						// 0x + len
+						if value.len() != 2 + $size * 2 {
+							return Err(serde::Error::syntax("Invalid length."));
+						}
+
+						value[2..].from_hex().map(|ref v| $from::from_slice(v)).map_err(|_| serde::Error::syntax("Invalid valid hex."))
+					}
+
+					fn visit_string<E>(&mut self, value: String) -> Result<Self::Value, E> where E: serde::Error {
+						self.visit_str(value.as_ref())
+					}
+				}
+
+				deserializer.visit(HashVisitor)
+			}
+		}
+
 		impl FromJson for $from {
 			fn from_json(json: &Json) -> Self {
-				match json {
-					&Json::String(ref s) => {
+				match *json {
+					Json::String(ref s) => {
 						match s.len() % 2 {
 							0 => FromStr::from_str(clean_0x(s)).unwrap(),
-							_ => FromStr::from_str(&("0".to_string() + &(clean_0x(s).to_string()))[..]).unwrap()
+							_ => FromStr::from_str(&("0".to_owned() + &(clean_0x(s).to_owned()))[..]).unwrap()
 						}
 					},
 					_ => Default::default(),
@@ -221,7 +268,7 @@ macro_rules! impl_hash {
 
 		impl fmt::Debug for $from {
 			fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-				for i in self.0.iter() {
+				for i in &self.0[..] {
 					try!(write!(f, "{:02x}", i));
 				}
 				Ok(())
@@ -229,11 +276,11 @@ macro_rules! impl_hash {
 		}
 		impl fmt::Display for $from {
 			fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-				for i in self.0[0..2].iter() {
+				for i in &self.0[0..2] {
 					try!(write!(f, "{:02x}", i));
 				}
 				try!(write!(f, "…"));
-				for i in self.0[$size - 4..$size].iter() {
+				for i in &self.0[$size - 4..$size] {
 					try!(write!(f, "{:02x}", i));
 				}
 				Ok(())
@@ -291,36 +338,36 @@ macro_rules! impl_hash {
 		impl Index<usize> for $from {
 			type Output = u8;
 
-			fn index<'a>(&'a self, index: usize) -> &'a u8 {
+			fn index(&self, index: usize) -> &u8 {
 				&self.0[index]
 			}
 		}
 		impl IndexMut<usize> for $from {
-			fn index_mut<'a>(&'a mut self, index: usize) -> &'a mut u8 {
+			fn index_mut(&mut self, index: usize) -> &mut u8 {
 				&mut self.0[index]
 			}
 		}
 		impl Index<ops::Range<usize>> for $from {
 			type Output = [u8];
 
-			fn index<'a>(&'a self, index: ops::Range<usize>) -> &'a [u8] {
+			fn index(&self, index: ops::Range<usize>) -> &[u8] {
 				&self.0[index]
 			}
 		}
 		impl IndexMut<ops::Range<usize>> for $from {
-			fn index_mut<'a>(&'a mut self, index: ops::Range<usize>) -> &'a mut [u8] {
+			fn index_mut(&mut self, index: ops::Range<usize>) -> &mut [u8] {
 				&mut self.0[index]
 			}
 		}
 		impl Index<ops::RangeFull> for $from {
 			type Output = [u8];
 
-			fn index<'a>(&'a self, _index: ops::RangeFull) -> &'a [u8] {
+			fn index(&self, _index: ops::RangeFull) -> &[u8] {
 				&self.0
 			}
 		}
 		impl IndexMut<ops::RangeFull> for $from {
-			fn index_mut<'a>(&'a mut self, _index: ops::RangeFull) -> &'a mut [u8] {
+			fn index_mut(&mut self, _index: ops::RangeFull) -> &mut [u8] {
 				&mut self.0
 			}
 		}
@@ -440,9 +487,9 @@ macro_rules! impl_hash {
 			fn from(s: &'_ str) -> $from {
 				use std::str::FromStr;
 				if s.len() % 2 == 1 {
-					$from::from_str(&("0".to_string() + &(clean_0x(s).to_string()))[..]).unwrap_or($from::new())
+					$from::from_str(&("0".to_owned() + &(clean_0x(s).to_owned()))[..]).unwrap_or_else(|_| $from::new())
 				} else {
-					$from::from_str(clean_0x(s)).unwrap_or($from::new())
+					$from::from_str(clean_0x(s)).unwrap_or_else(|_| $from::new())
 				}
 			}
 		}
@@ -469,6 +516,18 @@ impl<'_> From<&'_ U256> for H256 {
 	}
 }
 
+impl From<H256> for U256 {
+	fn from(value: H256) -> U256 {
+		U256::from(value.bytes())
+	}
+}
+
+impl<'_> From<&'_ H256> for U256 {
+	fn from(value: &'_ H256) -> U256 {
+		U256::from(value.bytes())
+	}
+}
+
 impl From<H256> for Address {
 	fn from(value: H256) -> Address {
 		unsafe {
@@ -562,9 +621,11 @@ pub static ZERO_H256: H256 = H256([0x00; 32]);
 #[cfg(test)]
 mod tests {
 	use hash::*;
+	use uint::*;
 	use std::str::FromStr;
 
 	#[test]
+	#[allow(eq_op)]
 	fn hash() {
 		let h = H64([0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef]);
 		assert_eq!(H64::from_str("0123456789abcdef").unwrap(), h);
@@ -634,5 +695,18 @@ mod tests {
 		// too short.
 		assert_eq!(H64::from(0), H64::from("0x34567890abcdef"));
 	}
+
+	#[test]
+	fn from_and_to_u256() {
+		let u: U256 = x!(0x123456789abcdef0u64);
+		let h = H256::from(u);
+		assert_eq!(H256::from(u), H256::from("000000000000000000000000000000000000000000000000123456789abcdef0"));
+		let h_ref = H256::from(&u);
+		assert_eq!(h, h_ref);
+		let r_ref: U256 = From::from(&h);
+		assert_eq!(r_ref, u);
+		let r: U256 = From::from(h);
+		assert_eq!(r, u);
+	}
 }
 

util/src/io/mod.rs

@@ -8,27 +8,28 @@
 ///
 /// struct MyHandler;
 ///
+/// #[derive(Clone)]
 /// struct MyMessage {
 /// 	data: u32
 /// }
 ///
 ///	impl IoHandler<MyMessage> for MyHandler {
-///		fn initialize(&mut self, io: &mut IoContext<MyMessage>) {
-///			io.register_timer(1000).unwrap();
+///		fn initialize(&self, io: &IoContext<MyMessage>) {
+///			io.register_timer(0, 1000).unwrap();
 ///		}
 ///
-///		fn timeout(&mut self, _io: &mut IoContext<MyMessage>, timer: TimerToken) {
+///		fn timeout(&self, _io: &IoContext<MyMessage>, timer: TimerToken) {
 ///			println!("Timeout {}", timer);
 ///		}
 ///
-///		fn message(&mut self, _io: &mut IoContext<MyMessage>, message: &mut MyMessage) {
+///		fn message(&self, _io: &IoContext<MyMessage>, message: &MyMessage) {
 ///			println!("Message {}", message.data);
 ///		}
 ///	}
 ///
 /// fn main () {
 /// 	let mut service = IoService::<MyMessage>::start().expect("Error creating network service");
-/// 	service.register_handler(Box::new(MyHandler)).unwrap();
+/// 	service.register_handler(Arc::new(MyHandler)).unwrap();
 ///
 /// 	// Wait for quit condition
 /// 	// ...
@@ -36,6 +37,9 @@
 /// }
 /// ```
 mod service;
+mod worker;
+
+use mio::{EventLoop, Token};
 
 #[derive(Debug)]
 /// TODO [arkpar] Please document me
@@ -44,7 +48,7 @@ pub enum IoError {
 	Mio(::std::io::Error),
 }
 
-impl<Message> From<::mio::NotifyError<service::IoMessage<Message>>> for IoError where Message: Send {
+impl<Message> From<::mio::NotifyError<service::IoMessage<Message>>> for IoError where Message: Send + Clone {
 	fn from(_err: ::mio::NotifyError<service::IoMessage<Message>>) -> IoError {
 		IoError::Mio(::std::io::Error::new(::std::io::ErrorKind::ConnectionAborted, "Network IO notification error"))
 	}
@@ -53,54 +57,65 @@ impl<Message> From<::mio::NotifyError<service::IoMessage<Message>>> for IoError
 /// Generic IO handler. 
 /// All the handler function are called from within IO event loop.
 /// `Message` type is used as notification data
-pub trait IoHandler<Message>: Send where Message: Send + 'static {
+pub trait IoHandler<Message>: Send + Sync where Message: Send + Sync + Clone + 'static {
 	/// Initialize the handler
-	fn initialize<'s>(&'s mut self, _io: &mut IoContext<'s, Message>) {}
+	fn initialize(&self, _io: &IoContext<Message>) {}
 	/// Timer function called after a timeout created with `HandlerIo::timeout`.
-	fn timeout<'s>(&'s mut self, _io: &mut IoContext<'s, Message>, _timer: TimerToken) {}
+	fn timeout(&self, _io: &IoContext<Message>, _timer: TimerToken) {}
 	/// Called when a broadcasted message is received. The message can only be sent from a different IO handler.
-	fn message<'s>(&'s mut self, _io: &mut IoContext<'s, Message>, _message: &'s mut Message) {} // TODO: make message immutable and provide internal channel for adding network handler
+	fn message(&self, _io: &IoContext<Message>, _message: &Message) {}
 	/// Called when an IO stream gets closed
-	fn stream_hup<'s>(&'s mut self, _io: &mut IoContext<'s, Message>, _stream: StreamToken) {}
+	fn stream_hup(&self, _io: &IoContext<Message>, _stream: StreamToken) {}
 	/// Called when an IO stream can be read from 
-	fn stream_readable<'s>(&'s mut self, _io: &mut IoContext<'s, Message>, _stream: StreamToken) {}
+	fn stream_readable(&self, _io: &IoContext<Message>, _stream: StreamToken) {}
 	/// Called when an IO stream can be written to
-	fn stream_writable<'s>(&'s mut self, _io: &mut IoContext<'s, Message>, _stream: StreamToken) {}
+	fn stream_writable(&self, _io: &IoContext<Message>, _stream: StreamToken) {}
+	/// Register a new stream with the event loop
+	fn register_stream(&self, _stream: StreamToken, _reg: Token, _event_loop: &mut EventLoop<IoManager<Message>>) {}
+	/// Re-register a stream with the event loop
+	fn update_stream(&self, _stream: StreamToken, _reg: Token, _event_loop: &mut EventLoop<IoManager<Message>>) {}
+	/// Deregister a stream. Called whenstream is removed from event loop
+	fn deregister_stream(&self, _stream: StreamToken, _event_loop: &mut EventLoop<IoManager<Message>>) {}
 }
 
 /// TODO [arkpar] Please document me
-pub type TimerToken = service::TimerToken;
+pub use io::service::TimerToken;
 /// TODO [arkpar] Please document me
-pub type StreamToken = service::StreamToken;
+pub use io::service::StreamToken;
 /// TODO [arkpar] Please document me
-pub type IoContext<'s, M> = service::IoContext<'s, M>;
+pub use io::service::IoContext;
 /// TODO [arkpar] Please document me
-pub type IoService<M> = service::IoService<M>;
+pub use io::service::IoService;
 /// TODO [arkpar] Please document me
-pub type IoChannel<M> = service::IoChannel<M>;
-//pub const USER_TOKEN_START: usize = service::USER_TOKEN; // TODO: ICE in rustc 1.7.0-nightly (49c382779 2016-01-12)
+pub use io::service::IoChannel;
+/// TODO [arkpar] Please document me
+pub use io::service::IoManager;
+/// TODO [arkpar] Please document me
+pub use io::service::TOKENS_PER_HANDLER;
 
 #[cfg(test)]
 mod tests {
 
+	use std::sync::Arc;
 	use io::*;
 
 	struct MyHandler;
 
+	#[derive(Clone)]
 	struct MyMessage {
 		data: u32
 	}
 
 	impl IoHandler<MyMessage> for MyHandler {
-		fn initialize(&mut self, io: &mut IoContext<MyMessage>) {
-			io.register_timer(1000).unwrap();
+		fn initialize(&self, io: &IoContext<MyMessage>) {
+			io.register_timer(0, 1000).unwrap();
 		}
 
-		fn timeout(&mut self, _io: &mut IoContext<MyMessage>, timer: TimerToken) {
+		fn timeout(&self, _io: &IoContext<MyMessage>, timer: TimerToken) {
 			println!("Timeout {}", timer);
 		}
 
-		fn message(&mut self, _io: &mut IoContext<MyMessage>, message: &mut MyMessage) {
+		fn message(&self, _io: &IoContext<MyMessage>, message: &MyMessage) {
 			println!("Message {}", message.data);
 		}
 	}
@@ -108,7 +123,7 @@ mod tests {
 	#[test]
 	fn test_service_register_handler () {
 		let mut service = IoService::<MyMessage>::start().expect("Error creating network service");
-		service.register_handler(Box::new(MyHandler)).unwrap();
+		service.register_handler(Arc::new(MyHandler)).unwrap();
 	}
 
 }

util/src/io/service.rs

@@ -1,148 +1,247 @@
+use std::sync::*;
 use std::thread::{self, JoinHandle};
+use std::collections::HashMap;
 use mio::*;
-use mio::util::{Slab};
 use hash::*;
 use rlp::*;
 use error::*;
 use io::{IoError, IoHandler};
+use arrayvec::*;
+use crossbeam::sync::chase_lev;
+use io::worker::{Worker, Work, WorkType};
 
+/// Timer ID
 pub type TimerToken = usize;
+/// Timer ID
 pub type StreamToken = usize;
+/// IO Hadndler ID
+pub type HandlerId = usize;
 
-// Tokens
-const MAX_USER_TIMERS: usize = 32;
-const USER_TIMER: usize = 0;
-const LAST_USER_TIMER: usize = USER_TIMER + MAX_USER_TIMERS - 1;
-//const USER_TOKEN: usize = LAST_USER_TIMER + 1;
+/// Maximum number of tokens a handler can use
+pub const TOKENS_PER_HANDLER: usize = 16384;
 
 /// Messages used to communicate with the event loop from other threads.
-pub enum IoMessage<Message> where Message: Send + Sized {
+#[derive(Clone)]
+pub enum IoMessage<Message> where Message: Send + Clone + Sized {
 	/// Shutdown the event loop
 	Shutdown,
 	/// Register a new protocol handler.
 	AddHandler {
-		handler: Box<IoHandler<Message>+Send>,
+		handler: Arc<IoHandler<Message>+Send>,
+	},
+	AddTimer {
+		handler_id: HandlerId,
+		token: TimerToken,
+		delay: u64,
+	},
+	RemoveTimer {
+		handler_id: HandlerId,
+		token: TimerToken,
+	},
+	RegisterStream {
+		handler_id: HandlerId,
+		token: StreamToken,
+	},
+	DeregisterStream {
+		handler_id: HandlerId,
+		token: StreamToken,
+	},
+	UpdateStreamRegistration {
+		handler_id: HandlerId,
+		token: StreamToken,
 	},
 	/// Broadcast a message across all protocol handlers.
 	UserMessage(Message)
 }
 
 /// IO access point. This is passed to all IO handlers and provides an interface to the IO subsystem.
-pub struct IoContext<'s, Message> where Message: Send + 'static {
-	timers: &'s mut Slab<UserTimer>,
-	/// Low leve MIO Event loop for custom handler registration.
-	pub event_loop: &'s mut EventLoop<IoManager<Message>>,
+pub struct IoContext<Message> where Message: Send + Clone + 'static {
+	channel: IoChannel<Message>,
+	handler: HandlerId,
 }
 
-impl<'s, Message> IoContext<'s, Message> where Message: Send + 'static {
+impl<Message> IoContext<Message> where Message: Send + Clone + 'static {
 	/// Create a new IO access point. Takes references to all the data that can be updated within the IO handler.
-	fn new(event_loop: &'s mut EventLoop<IoManager<Message>>, timers: &'s mut Slab<UserTimer>) -> IoContext<'s, Message> {
+	pub fn new(channel: IoChannel<Message>, handler: HandlerId) -> IoContext<Message> {
 		IoContext {
-			event_loop: event_loop,
-			timers: timers,
+			handler: handler,
+			channel: channel,
 		}
 	}
 
-	/// Register a new IO timer. Returns a new timer token. 'IoHandler::timeout' will be called with the token.
-	pub fn register_timer(&mut self, ms: u64) -> Result<TimerToken, UtilError> {
-		match self.timers.insert(UserTimer {
+	/// Register a new IO timer. 'IoHandler::timeout' will be called with the token.
+	pub fn register_timer(&self, token: TimerToken, ms: u64) -> Result<(), UtilError> {
+		try!(self.channel.send_io(IoMessage::AddTimer {
+			token: token,
 			delay: ms,
-		}) {
-			Ok(token) => {
-				self.event_loop.timeout_ms(token, ms).expect("Error registering user timer");
-				Ok(token.as_usize())
-			},
-			_ => { panic!("Max timers reached") }
-		}
+			handler_id: self.handler,
+		}));
+		Ok(())
+	}
+
+	/// Delete a timer.
+	pub fn clear_timer(&self, token: TimerToken) -> Result<(), UtilError> {
+		try!(self.channel.send_io(IoMessage::RemoveTimer {
+			token: token,
+			handler_id: self.handler,
+		}));
+		Ok(())
+	}
+
+	/// Register a new IO stream.
+	pub fn register_stream(&self, token: StreamToken) -> Result<(), UtilError> {
+		try!(self.channel.send_io(IoMessage::RegisterStream {
+			token: token,
+			handler_id: self.handler,
+		}));
+		Ok(())
+	}
+
+	/// Deregister an IO stream.
+	pub fn deregister_stream(&self, token: StreamToken) -> Result<(), UtilError> {
+		try!(self.channel.send_io(IoMessage::DeregisterStream {
+			token: token,
+			handler_id: self.handler,
+		}));
+		Ok(())
+	}
+
+	/// Reregister an IO stream.
+	pub fn update_registration(&self, token: StreamToken) -> Result<(), UtilError> {
+		try!(self.channel.send_io(IoMessage::UpdateStreamRegistration {
+			token: token,
+			handler_id: self.handler,
+		}));
+		Ok(())
 	}
 
 	/// Broadcast a message to other IO clients
-	pub fn message(&mut self, message: Message) {
-		match self.event_loop.channel().send(IoMessage::UserMessage(message)) {
-			Ok(_) => {}
-			Err(e) => { panic!("Error sending io message {:?}", e); }
-		}
+	pub fn message(&self, message: Message) {
+		self.channel.send(message).expect("Error seding message");
+	}
+
+	/// Get message channel
+	pub fn channel(&self) -> IoChannel<Message> {
+		self.channel.clone()
 	}
 }
 
+#[derive(Clone)]
 struct UserTimer {
 	delay: u64,
+	timeout: Timeout,
 }
 
 /// Root IO handler. Manages user handlers, messages and IO timers.
-pub struct IoManager<Message> where Message: Send {
-	timers: Slab<UserTimer>,
-	handlers: Vec<Box<IoHandler<Message>>>,
+pub struct IoManager<Message> where Message: Send + Sync {
+	timers: Arc<RwLock<HashMap<HandlerId, UserTimer>>>,
+	handlers: Vec<Arc<IoHandler<Message>>>,
+	_workers: Vec<Worker>,
+	worker_channel: chase_lev::Worker<Work<Message>>,
+	work_ready: Arc<Condvar>,
 }
 
-impl<Message> IoManager<Message> where Message: Send + 'static {
+impl<Message> IoManager<Message> where Message: Send + Sync + Clone + 'static {
 	/// Creates a new instance and registers it with the event loop.
 	pub fn start(event_loop: &mut EventLoop<IoManager<Message>>) -> Result<(), UtilError> {
+		let (worker, stealer) = chase_lev::deque();
+		let num_workers = 4;
+		let work_ready_mutex =  Arc::new(Mutex::new(()));
+		let work_ready = Arc::new(Condvar::new());
+		let workers = (0..num_workers).map(|i| 
+			Worker::new(i, stealer.clone(), IoChannel::new(event_loop.channel()), work_ready.clone(), work_ready_mutex.clone())).collect();
+
 		let mut io = IoManager {
-			timers: Slab::new_starting_at(Token(USER_TIMER), MAX_USER_TIMERS),
+			timers: Arc::new(RwLock::new(HashMap::new())),
 			handlers: Vec::new(),
+			worker_channel: worker,
+			_workers: workers,
+			work_ready: work_ready,
 		};
 		try!(event_loop.run(&mut io));
 		Ok(())
 	}
 }
 
-impl<Message> Handler for IoManager<Message> where Message: Send + 'static {
+impl<Message> Handler for IoManager<Message> where Message: Send + Clone + Sync + 'static {
 	type Timeout = Token;
 	type Message = IoMessage<Message>;
 
-	fn ready(&mut self, event_loop: &mut EventLoop<Self>, token: Token, events: EventSet) {
+	fn ready(&mut self, _event_loop: &mut EventLoop<Self>, token: Token, events: EventSet) {
+		let handler_index  = token.as_usize() / TOKENS_PER_HANDLER;
+		let token_id  = token.as_usize() % TOKENS_PER_HANDLER;
+		if handler_index >= self.handlers.len() {
+			panic!("Unexpected stream token: {}", token.as_usize());
+		}
+		let handler = self.handlers[handler_index].clone();
+
 		if events.is_hup() {
-			for h in self.handlers.iter_mut() {
-				h.stream_hup(&mut IoContext::new(event_loop, &mut self.timers), token.as_usize());
-			}
-		}
-		else if events.is_readable() {
-			for h in self.handlers.iter_mut() {
-				h.stream_readable(&mut IoContext::new(event_loop, &mut self.timers), token.as_usize());
-			}
-		}
-		else if events.is_writable() {
-			for h in self.handlers.iter_mut() {
-				h.stream_writable(&mut IoContext::new(event_loop, &mut self.timers), token.as_usize());
+			self.worker_channel.push(Work { work_type: WorkType::Hup, token: token_id, handler: handler.clone(), handler_id: handler_index });
+		}
+		else {
+			if events.is_readable() {
+				self.worker_channel.push(Work { work_type: WorkType::Readable, token: token_id, handler: handler.clone(), handler_id: handler_index });
+			}
+			if events.is_writable() {
+				self.worker_channel.push(Work { work_type: WorkType::Writable, token: token_id, handler: handler.clone(), handler_id: handler_index });
 			}
 		}
+		self.work_ready.notify_all();
 	}
 
 	fn timeout(&mut self, event_loop: &mut EventLoop<Self>, token: Token) {
-		match token.as_usize() {
-			USER_TIMER ... LAST_USER_TIMER => {
-				let delay = {
-					let timer = self.timers.get_mut(token).expect("Unknown user timer token");
-					timer.delay
-				};
-				for h in self.handlers.iter_mut() {
-					h.timeout(&mut IoContext::new(event_loop, &mut self.timers), token.as_usize());
-				}
-				event_loop.timeout_ms(token, delay).expect("Error re-registering user timer");
-			}
-			_ => { // Just pass the event down. IoHandler is supposed to re-register it if required.
-				for h in self.handlers.iter_mut() {
-					h.timeout(&mut IoContext::new(event_loop, &mut self.timers), token.as_usize());
-				}
-			}
+		let handler_index  = token.as_usize()  / TOKENS_PER_HANDLER;
+		let token_id  = token.as_usize()  % TOKENS_PER_HANDLER;
+		if handler_index >= self.handlers.len() {
+			panic!("Unexpected timer token: {}", token.as_usize());
+		}
+		if let Some(timer) = self.timers.read().unwrap().get(&token.as_usize()) {
+			event_loop.timeout_ms(token, timer.delay).expect("Error re-registering user timer");
+			let handler = self.handlers[handler_index].clone();
+			self.worker_channel.push(Work { work_type: WorkType::Timeout, token: token_id, handler: handler, handler_id: handler_index });
+			self.work_ready.notify_all();
 		}
 	}
 
 	fn notify(&mut self, event_loop: &mut EventLoop<Self>, msg: Self::Message) {
-		let mut m = msg;
-		match m {
+		match msg {
 			IoMessage::Shutdown => event_loop.shutdown(),
-			IoMessage::AddHandler {
-				handler,
-			} => {
-				self.handlers.push(handler);
-				self.handlers.last_mut().unwrap().initialize(&mut IoContext::new(event_loop, &mut self.timers));
+			IoMessage::AddHandler { handler } => {
+				let handler_id = {
+					self.handlers.push(handler.clone());
+					self.handlers.len() - 1
+				};
+				handler.initialize(&IoContext::new(IoChannel::new(event_loop.channel()), handler_id));
 			},
-			IoMessage::UserMessage(ref mut data) => {
-				for h in self.handlers.iter_mut() {
-					h.message(&mut IoContext::new(event_loop, &mut self.timers), data);
+			IoMessage::AddTimer { handler_id, token, delay } => {
+				let timer_id = token + handler_id * TOKENS_PER_HANDLER;
+				let timeout = event_loop.timeout_ms(Token(timer_id), delay).expect("Error registering user timer");
+				self.timers.write().unwrap().insert(timer_id, UserTimer { delay: delay, timeout: timeout });
+			},
+			IoMessage::RemoveTimer { handler_id, token } => {
+				let timer_id = token + handler_id * TOKENS_PER_HANDLER;
+				if let Some(timer) = self.timers.write().unwrap().remove(&timer_id) {
+					event_loop.clear_timeout(timer.timeout);
 				}
+			},
+			IoMessage::RegisterStream { handler_id, token } => {
+				let handler = self.handlers.get(handler_id).expect("Unknown handler id").clone();
+				handler.register_stream(token, Token(token + handler_id * TOKENS_PER_HANDLER), event_loop);
+			},
+			IoMessage::DeregisterStream { handler_id, token } => {
+				let handler = self.handlers.get(handler_id).expect("Unknown handler id").clone();
+				handler.deregister_stream(token, event_loop);
+			},
+			IoMessage::UpdateStreamRegistration { handler_id, token } => {
+				let handler = self.handlers.get(handler_id).expect("Unknown handler id").clone();
+				handler.update_stream(token, Token(token + handler_id * TOKENS_PER_HANDLER), event_loop);
+			},
+			IoMessage::UserMessage(data) => {
+				for n in 0 .. self.handlers.len() {
+					let handler = self.handlers[n].clone();
+					self.worker_channel.push(Work { work_type: WorkType::Message(data.clone()), token: 0, handler: handler, handler_id: n });
+				}
+				self.work_ready.notify_all();
 			}
 		}
 	}
@@ -150,11 +249,19 @@ impl<Message> Handler for IoManager<Message> where Message: Send + 'static {
 
 /// Allows sending messages into the event loop. All the IO handlers will get the message
 /// in the `message` callback.
-pub struct IoChannel<Message> where Message: Send {
+pub struct IoChannel<Message> where Message: Send + Clone{
 	channel: Option<Sender<IoMessage<Message>>>
 }
 
-impl<Message> IoChannel<Message> where Message: Send {
+impl<Message> Clone for IoChannel<Message> where Message: Send + Clone {
+	fn clone(&self) -> IoChannel<Message> {
+		IoChannel {
+			channel: self.channel.clone()
+		}
+	}
+}
+
+impl<Message> IoChannel<Message> where Message: Send + Clone {
 	/// Send a msessage through the channel
 	pub fn send(&self, message: Message) -> Result<(), IoError> {
 		if let Some(ref channel) = self.channel {
@@ -163,20 +270,31 @@ impl<Message> IoChannel<Message> where Message: Send {
 		Ok(())
 	}
 
+	/// Send low level io message
+	pub fn send_io(&self, message: IoMessage<Message>) -> Result<(), IoError> {
+		if let Some(ref channel) = self.channel {
+			try!(channel.send(message))
+		}
+		Ok(())
+	}
 	/// Create a new channel to connected to event loop.
 	pub fn disconnected() -> IoChannel<Message> {
 		IoChannel { channel: None }
 	}
+
+	fn new(channel: Sender<IoMessage<Message>>) -> IoChannel<Message> {
+		IoChannel { channel: Some(channel) }
+	}
 }
 
 /// General IO Service. Starts an event loop and dispatches IO requests.
 /// 'Message' is a notification message type
-pub struct IoService<Message> where Message: Send + 'static {
+pub struct IoService<Message> where Message: Send + Sync + Clone + 'static {
 	thread: Option<JoinHandle<()>>,
-	host_channel: Sender<IoMessage<Message>>
+	host_channel: Sender<IoMessage<Message>>,
 }
 
-impl<Message> IoService<Message> where Message: Send + 'static {
+impl<Message> IoService<Message> where Message: Send + Sync + Clone + 'static {
 	/// Starts IO event loop
 	pub fn start() -> Result<IoService<Message>, UtilError> {
 		let mut event_loop = EventLoop::new().unwrap();
@@ -191,7 +309,7 @@ impl<Message> IoService<Message> where Message: Send + 'static {
 	}
 
 	/// Regiter a IO hadnler with the event loop.
-	pub fn register_handler(&mut self, handler: Box<IoHandler<Message>+Send>) -> Result<(), IoError> {
+	pub fn register_handler(&mut self, handler: Arc<IoHandler<Message>+Send>) -> Result<(), IoError> {
 		try!(self.host_channel.send(IoMessage::AddHandler {
 			handler: handler,
 		}));
@@ -210,10 +328,10 @@ impl<Message> IoService<Message> where Message: Send + 'static {
 	}
 }
 
-impl<Message> Drop for IoService<Message> where Message: Send {
+impl<Message> Drop for IoService<Message> where Message: Send + Sync + Clone {
 	fn drop(&mut self) {
 		self.host_channel.send(IoMessage::Shutdown).unwrap();
-		self.thread.take().unwrap().join().unwrap();
+		self.thread.take().unwrap().join().ok();
 	}
 }
 

util/src/io/worker.rs

@@ -0,0 +1,99 @@
+use std::sync::*;
+use std::mem;
+use std::thread::{JoinHandle, self};
+use std::sync::atomic::{AtomicBool, Ordering as AtomicOrdering};
+use crossbeam::sync::chase_lev;
+use io::service::{HandlerId, IoChannel, IoContext};
+use io::{IoHandler};
+
+pub enum WorkType<Message> {
+	Readable,
+	Writable,
+	Hup,
+	Timeout,
+	Message(Message)
+}
+
+pub struct Work<Message> {
+	pub work_type: WorkType<Message>,
+	pub token: usize,
+	pub handler_id: HandlerId,
+	pub handler: Arc<IoHandler<Message>>,
+}
+
+/// An IO worker thread
+/// Sorts them ready for blockchain insertion.
+pub struct Worker {
+	thread: Option<JoinHandle<()>>,
+	wait: Arc<Condvar>,
+	deleting: Arc<AtomicBool>,
+}
+
+impl Worker {
+	/// Creates a new worker instance.
+	pub fn new<Message>(index: usize, 
+						stealer: chase_lev::Stealer<Work<Message>>, 
+						channel: IoChannel<Message>,
+						wait: Arc<Condvar>,
+						wait_mutex: Arc<Mutex<()>>) -> Worker 
+						where Message: Send + Sync + Clone + 'static {
+		let deleting = Arc::new(AtomicBool::new(false));
+		let mut worker = Worker {
+			thread: None,
+			wait: wait.clone(),
+			deleting: deleting.clone(),
+		};
+		worker.thread = Some(thread::Builder::new().name(format!("IO Worker #{}", index)).spawn(
+			move || Worker::work_loop(stealer, channel.clone(), wait, wait_mutex.clone(), deleting))
+			.expect("Error creating worker thread"));
+		worker
+	}
+
+	fn work_loop<Message>(stealer: chase_lev::Stealer<Work<Message>>,
+						channel: IoChannel<Message>, wait: Arc<Condvar>, 
+						wait_mutex: Arc<Mutex<()>>, 
+						deleting: Arc<AtomicBool>) 
+						where Message: Send + Sync + Clone + 'static {
+		while !deleting.load(AtomicOrdering::Relaxed) {
+			{
+				let lock = wait_mutex.lock().unwrap();
+				let _ = wait.wait(lock).unwrap();
+				if deleting.load(AtomicOrdering::Relaxed) {
+					return;
+				}
+			}
+			while let chase_lev::Steal::Data(work) = stealer.steal() {
+				Worker::do_work(work, channel.clone());
+			}
+		}
+	}
+
+	fn do_work<Message>(work: Work<Message>, channel: IoChannel<Message>) where Message: Send + Sync + Clone + 'static {
+		match work.work_type {
+			WorkType::Readable => {
+				work.handler.stream_readable(&IoContext::new(channel, work.handler_id), work.token);
+			},
+			WorkType::Writable => {
+				work.handler.stream_writable(&IoContext::new(channel, work.handler_id), work.token);
+			}
+			WorkType::Hup => {
+				work.handler.stream_hup(&IoContext::new(channel, work.handler_id), work.token);
+			}
+			WorkType::Timeout => {
+				work.handler.timeout(&IoContext::new(channel, work.handler_id), work.token);
+			}
+			WorkType::Message(message) => {
+				work.handler.message(&IoContext::new(channel, work.handler_id), &message);
+			}
+		}
+	}
+}
+
+impl Drop for Worker {
+	fn drop(&mut self) {
+		self.deleting.store(true, AtomicOrdering::Relaxed);
+		self.wait.notify_all();
+		let thread = mem::replace(&mut self.thread, None).unwrap();
+		thread.join().ok();
+	}
+}

util/src/journaldb.rs

@@ -34,6 +34,16 @@ impl JournalDB {
 		}
 	}
 
+	/// Create a new instance given a shared `backing` database.
+	pub fn new_with_arc(backing: Arc<DB>) -> JournalDB {
+		JournalDB {
+			forward: OverlayDB::new_with_arc(backing.clone()),
+			backing: backing,
+			inserts: vec![],
+			removes: vec![],
+		}
+	}
+
 	/// Create a new instance with an anonymous temporary database.
 	pub fn new_temp() -> JournalDB {
 		let mut dir = env::temp_dir();
@@ -96,7 +106,7 @@ impl JournalDB {
 			})) {
 				let rlp = Rlp::new(&rlp_data);
 				let to_remove: Vec<H256> = rlp.val_at(if canon_id == rlp.val_at(0) {2} else {1});
-				for i in to_remove.iter() {
+				for i in &to_remove {
 					self.forward.remove(i);
 				}
 				try!(self.backing.delete(&last));

util/src/json_aid.rs

@@ -11,18 +11,18 @@ pub fn clean(s: &str) -> &str {
 
 fn u256_from_str(s: &str) -> U256 {
 	if s.len() >= 2 && &s[0..2] == "0x" {
-		U256::from_str(&s[2..]).unwrap_or(U256::from(0))
+		U256::from_str(&s[2..]).unwrap_or_else(|_| U256::zero())
 	} else {
-		U256::from_dec_str(s).unwrap_or(U256::from(0))
+		U256::from_dec_str(s).unwrap_or_else(|_| U256::zero())
 	}
 }
 
 impl FromJson for Bytes {
 	fn from_json(json: &Json) -> Self {
-		match json {
-			&Json::String(ref s) => match s.len() % 2 {
-				0 => FromHex::from_hex(clean(s)).unwrap_or(vec![]),
-				_ => FromHex::from_hex(&("0".to_string() + &(clean(s).to_string()))[..]).unwrap_or(vec![]),
+		match *json {
+			Json::String(ref s) => match s.len() % 2 {
+				0 => FromHex::from_hex(clean(s)).unwrap_or_else(|_| vec![]),
+				_ => FromHex::from_hex(&("0".to_owned() + &(clean(s).to_owned()))[..]).unwrap_or_else(|_| vec![]),
 			},
 			_ => vec![],
 		}
@@ -31,8 +31,8 @@ impl FromJson for Bytes {
 
 impl FromJson for BTreeMap<H256, H256> {
 	fn from_json(json: &Json) -> Self {
-		match json {
-			&Json::Object(ref o) => o.iter().map(|(key, value)| (x!(&u256_from_str(key)), x!(&U256::from_json(value)))).collect(),
+		match *json {
+			Json::Object(ref o) => o.iter().map(|(key, value)| (x!(&u256_from_str(key)), x!(&U256::from_json(value)))).collect(),
 			_ => BTreeMap::new(),
 		}
 	}
@@ -40,8 +40,8 @@ impl FromJson for BTreeMap<H256, H256> {
 
 impl<T> FromJson for Vec<T> where T: FromJson {
 	fn from_json(json: &Json) -> Self {
-		match json {
-			&Json::Array(ref o) => o.iter().map(|x|T::from_json(x)).collect(),
+		match *json {
+			Json::Array(ref o) => o.iter().map(|x|T::from_json(x)).collect(),
 			_ => Vec::new(),
 		}
 	}
@@ -49,9 +49,9 @@ impl<T> FromJson for Vec<T> where T: FromJson {
 
 impl<T> FromJson for Option<T> where T: FromJson {
 	fn from_json(json: &Json) -> Self {
-		match json {
-			&Json::String(ref o) if o.is_empty() => None,
-			&Json::Null => None,
+		match *json {
+			Json::String(ref o) if o.is_empty() => None,
+			Json::Null => None,
 			_ => Some(FromJson::from_json(json)),
 		}
 	}
@@ -135,4 +135,4 @@ fn option_types() {
 	assert_eq!(None, v);
 	let v: Option<u16> = xjson!(&j["empty"]);
 	assert_eq!(None, v);
-}
+}

util/src/lib.rs

@@ -2,6 +2,9 @@
 #![feature(op_assign_traits)]
 #![feature(augmented_assignments)]
 #![feature(associated_consts)]
+#![feature(plugin)]
+#![plugin(clippy)]
+#![allow(needless_range_loop, match_bool)]
 //! Ethcore-util library
 //!
 //! ### Rust version:
@@ -51,6 +54,8 @@ extern crate crypto as rcrypto;
 extern crate secp256k1;
 extern crate arrayvec;
 extern crate elastic_array;
+extern crate crossbeam;
+extern crate serde;
 
 /// TODO [Gav Wood] Please document me
 pub mod standard;

util/src/misc.rs

@@ -18,13 +18,13 @@ impl<T> Diff<T> where T: Eq {
 	pub fn new(pre: T, post: T) -> Self { if pre == post { Diff::Same } else { Diff::Changed(pre, post) } }
 
 	/// Get the before value, if there is one.
-	pub fn pre(&self) -> Option<&T> { match self { &Diff::Died(ref x) | &Diff::Changed(ref x, _) => Some(x), _ => None } }
+	pub fn pre(&self) -> Option<&T> { match *self { Diff::Died(ref x) | Diff::Changed(ref x, _) => Some(x), _ => None } }
 
 	/// Get the after value, if there is one.
-	pub fn post(&self) -> Option<&T> { match self { &Diff::Born(ref x) | &Diff::Changed(_, ref x) => Some(x), _ => None } }
+	pub fn post(&self) -> Option<&T> { match *self { Diff::Born(ref x) | Diff::Changed(_, ref x) => Some(x), _ => None } }
 
 	/// Determine whether there was a change or not.
-	pub fn is_same(&self) -> bool { match self { &Diff::Same => true, _ => false }}
+	pub fn is_same(&self) -> bool { match *self { Diff::Same => true, _ => false }}
 }
 
 #[derive(PartialEq,Eq,Clone,Copy)]

util/src/network/connection.rs

@@ -1,5 +1,6 @@
+use std::sync::Arc;
 use std::collections::VecDeque;
-use mio::{Handler, Token, EventSet, EventLoop, Timeout, PollOpt, TryRead, TryWrite};
+use mio::{Handler, Token, EventSet, EventLoop, PollOpt, TryRead, TryWrite};
 use mio::tcp::*;
 use hash::*;
 use sha3::*;
@@ -7,8 +8,10 @@ use bytes::*;
 use rlp::*;
 use std::io::{self, Cursor, Read};
 use error::*;
+use io::{IoContext, StreamToken};
 use network::error::NetworkError;
 use network::handshake::Handshake;
+use network::stats::NetworkStats;
 use crypto;
 use rcrypto::blockmodes::*;
 use rcrypto::aessafe::*;
@@ -17,11 +20,12 @@ use rcrypto::buffer::*;
 use tiny_keccak::Keccak;
 
 const ENCRYPTED_HEADER_LEN: usize = 32;
+const RECIEVE_PAYLOAD_TIMEOUT: u64 = 30000;
 
 /// Low level tcp connection
 pub struct Connection {
 	/// Connection id (token)
-	pub token: Token,
+	pub token: StreamToken,
 	/// Network socket
 	pub socket: TcpStream,
 	/// Receive buffer
@@ -32,6 +36,8 @@ pub struct Connection {
 	send_queue: VecDeque<Cursor<Bytes>>,
 	/// Event flags this connection expects
 	interest: EventSet,
+	/// Shared network staistics
+	stats: Arc<NetworkStats>,
 }
 
 /// Connection write status.
@@ -45,14 +51,15 @@ pub enum WriteStatus {
 
 impl Connection {
 	/// Create a new connection with given id and socket.
-	pub fn new(token: Token, socket: TcpStream) -> Connection {
+	pub fn new(token: StreamToken, socket: TcpStream, stats: Arc<NetworkStats>) -> Connection {
 		Connection {
 			token: token,
 			socket: socket,
 			send_queue: VecDeque::new(),
 			rec_buf: Bytes::new(),
 			rec_size: 0,
-			interest: EventSet::hup(),
+			interest: EventSet::hup() | EventSet::readable(),
+			stats: stats,
 		}
 	}
 
@@ -66,7 +73,6 @@ impl Connection {
 	}
 
 	/// Readable IO handler. Called when there is some data to be read.
-	//TODO: return a slice
 	pub fn readable(&mut self) -> io::Result<Option<Bytes>> {
 		if self.rec_size == 0 || self.rec_buf.len() >= self.rec_size {
 			warn!(target:"net", "Unexpected connection read");
@@ -75,9 +81,12 @@ impl Connection {
 		// resolve "multiple applicable items in scope [E0034]" error
 		let sock_ref = <TcpStream as Read>::by_ref(&mut self.socket);
 		match sock_ref.take(max as u64).try_read_buf(&mut self.rec_buf) {
-			Ok(Some(_)) if self.rec_buf.len() == self.rec_size => {
-				self.rec_size = 0;
-				Ok(Some(::std::mem::replace(&mut self.rec_buf, Bytes::new())))
+			Ok(Some(size)) if size != 0  => {
+				self.stats.inc_recv(size);
+				if self.rec_size != 0 && self.rec_buf.len() == self.rec_size {
+					self.rec_size = 0;
+					Ok(Some(::std::mem::replace(&mut self.rec_buf, Bytes::new())))
+				} else { Ok(None) }
 			},
 			Ok(_) => Ok(None),
 			Err(e) => Err(e),
@@ -86,7 +95,7 @@ impl Connection {
 
 	/// Add a packet to send queue.
 	pub fn send(&mut self, data: Bytes) {
-		if data.len() != 0 {
+		if !data.is_empty() {
 			self.send_queue.push_back(Cursor::new(data));
 		}
 		if !self.interest.is_writable() {
@@ -107,14 +116,17 @@ impl Connection {
 				return Ok(WriteStatus::Complete)
 			}
 			match self.socket.try_write_buf(buf) {
-				Ok(_) if (buf.position() as usize) < send_size => {
+				Ok(Some(size)) if (buf.position() as usize) < send_size => {
 					self.interest.insert(EventSet::writable());
+					self.stats.inc_send(size);
 					Ok(WriteStatus::Ongoing)
 				},
-				Ok(_) if (buf.position() as usize) == send_size => {
+				Ok(Some(size)) if (buf.position() as usize) == send_size => {
+					self.stats.inc_send(size);
 					Ok(WriteStatus::Complete)
 				},
-				Ok(_) => { panic!("Wrote past buffer");},
+				Ok(Some(_)) => { panic!("Wrote past buffer");},
+				Ok(None) => Ok(WriteStatus::Ongoing),
 				Err(e) => Err(e)
 			}
 		}.and_then(|r| {
@@ -132,23 +144,29 @@ impl Connection {
 	}
 
 	/// Register this connection with the IO event loop.
-	pub fn register<Host: Handler>(&mut self, event_loop: &mut EventLoop<Host>) -> io::Result<()> {
-		trace!(target: "net", "connection register; token={:?}", self.token);
-		self.interest.insert(EventSet::readable());
-		event_loop.register(&self.socket, self.token, self.interest, PollOpt::edge() | PollOpt::oneshot()).or_else(|e| {
-			error!("Failed to register {:?}, {:?}", self.token, e);
-			Err(e)
+	pub fn register_socket<Host: Handler>(&self, reg: Token, event_loop: &mut EventLoop<Host>) -> io::Result<()> {
+		trace!(target: "net", "connection register; token={:?}", reg);
+		event_loop.register(&self.socket, reg, self.interest, PollOpt::edge() | PollOpt::oneshot()).or_else(|e| {
+			debug!("Failed to register {:?}, {:?}", reg, e);
+			Ok(())
 		})
 	}
 
 	/// Update connection registration. Should be called at the end of the IO handler.
-	pub fn reregister<Host: Handler>(&mut self, event_loop: &mut EventLoop<Host>) -> io::Result<()> {
-		trace!(target: "net", "connection reregister; token={:?}", self.token);
-		event_loop.reregister( &self.socket, self.token, self.interest, PollOpt::edge() | PollOpt::oneshot()).or_else(|e| {
-			error!("Failed to reregister {:?}, {:?}", self.token, e);
-			Err(e)
+	pub fn update_socket<Host: Handler>(&self, reg: Token, event_loop: &mut EventLoop<Host>) -> io::Result<()> {
+		trace!(target: "net", "connection reregister; token={:?}", reg);
+		event_loop.reregister( &self.socket, reg, self.interest, PollOpt::edge() | PollOpt::oneshot()).or_else(|e| {
+			debug!("Failed to reregister {:?}, {:?}", reg, e);
+			Ok(())
 		})
 	}
+
+	/// Delete connection registration. Should be called at the end of the IO handler.
+	pub fn deregister_socket<Host: Handler>(&self, event_loop: &mut EventLoop<Host>) -> io::Result<()> {
+		trace!(target: "net", "connection deregister; token={:?}", self.token);
+		event_loop.deregister(&self.socket).ok(); // ignore errors here
+		Ok(())
+	}
 }
 
 /// RLPx packet
@@ -182,8 +200,6 @@ pub struct EncryptedConnection {
 	ingress_mac: Keccak,
 	/// Read state
 	read_state: EncryptedConnectionState,
-	/// Disconnect timeout
-	idle_timeout: Option<Timeout>,
 	/// Protocol id for the last received packet
 	protocol_id: u16,
 	/// Payload expected to be received for the last header.
@@ -192,7 +208,7 @@ pub struct EncryptedConnection {
 
 impl EncryptedConnection {
 	/// Create an encrypted connection out of the handshake. Consumes a handshake object.
-	pub fn new(handshake: Handshake) -> Result<EncryptedConnection, UtilError> {
+	pub fn new(mut handshake: Handshake) -> Result<EncryptedConnection, UtilError> {
 		let shared = try!(crypto::ecdh::agree(handshake.ecdhe.secret(), &handshake.remote_public));
 		let mut nonce_material = H512::new();
 		if handshake.originated {
@@ -227,6 +243,7 @@ impl EncryptedConnection {
 		ingress_mac.update(&mac_material);
 		ingress_mac.update(if handshake.originated { &handshake.ack_cipher } else { &handshake.auth_cipher });
 
+		handshake.connection.expect(ENCRYPTED_HEADER_LEN);
 		Ok(EncryptedConnection {
 			connection: handshake.connection,
 			encoder: encoder,
@@ -235,7 +252,6 @@ impl EncryptedConnection {
 			egress_mac: egress_mac,
 			ingress_mac: ingress_mac,
 			read_state: EncryptedConnectionState::Header,
-			idle_timeout: None,
 			protocol_id: 0,
 			payload_len: 0
 		})
@@ -337,16 +353,14 @@ impl EncryptedConnection {
 	}
 
 	/// Readable IO handler. Tracker receive status and returns decoded packet if avaialable.
-	pub fn readable<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>) -> Result<Option<Packet>, UtilError> {
-		self.idle_timeout.map(|t| event_loop.clear_timeout(t));
+	pub fn readable<Message>(&mut self, io: &IoContext<Message>) -> Result<Option<Packet>, UtilError> where Message: Send + Clone{
+		io.clear_timer(self.connection.token).unwrap();
 		match self.read_state {
 			EncryptedConnectionState::Header => {
-				match try!(self.connection.readable()) {
-					Some(data)  => {
-						try!(self.read_header(&data));
-					},
-					None => {}
-				};
+				if let Some(data) = try!(self.connection.readable()) {
+					try!(self.read_header(&data));
+					try!(io.register_timer(self.connection.token, RECIEVE_PAYLOAD_TIMEOUT));
+				}
 				Ok(None)
 			},
 			EncryptedConnectionState::Payload => {
@@ -363,24 +377,21 @@ impl EncryptedConnection {
 	}
 
 	/// Writable IO handler. Processes send queeue.
-	pub fn writable<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
-		self.idle_timeout.map(|t| event_loop.clear_timeout(t));
+	pub fn writable<Message>(&mut self, io: &IoContext<Message>) -> Result<(), UtilError> where Message: Send + Clone {
+		io.clear_timer(self.connection.token).unwrap();
 		try!(self.connection.writable());
 		Ok(())
 	}
 
-	/// Register this connection with the event handler.
-	pub fn register<Host:Handler<Timeout=Token>>(&mut self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
-		self.connection.expect(ENCRYPTED_HEADER_LEN);
-		self.idle_timeout.map(|t| event_loop.clear_timeout(t));
-		self.idle_timeout = event_loop.timeout_ms(self.connection.token, 1800).ok();
-		try!(self.connection.reregister(event_loop));
+	/// Update connection registration. This should be called at the end of the event loop.
+	pub fn update_socket<Host:Handler>(&self, reg: Token, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
+		try!(self.connection.update_socket(reg, event_loop));
 		Ok(())
 	}
 
-	/// Update connection registration. This should be called at the end of the event loop.
-	pub fn reregister<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
-		try!(self.connection.reregister(event_loop));
+	/// Delete connection registration. This should be called at the end of the event loop.
+	pub fn deregister_socket<Host:Handler>(&self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
+		try!(self.connection.deregister_socket(event_loop));
 		Ok(())
 	}
 }

util/src/network/discovery.rs

@@ -62,7 +62,7 @@ impl Discovery {
 			discovery_round: 0,
 			discovery_id: NodeId::new(),
 			discovery_nodes: HashSet::new(),
-			node_buckets: (0..NODE_BINS).map(|x| NodeBucket::new(x)).collect(),
+			node_buckets: (0..NODE_BINS).map(NodeBucket::new).collect(),
 		}
 	}
 
@@ -122,7 +122,8 @@ impl Discovery {
 		ret
 	}
 
-	fn nearest_node_entries<'b>(source: &NodeId, target: &NodeId, buckets: &'b Vec<NodeBucket>) -> Vec<&'b NodeId>
+	#[allow(cyclomatic_complexity)]
+	fn nearest_node_entries<'b>(source: &NodeId, target: &NodeId, buckets: &'b [NodeBucket]) -> Vec<&'b NodeId>
 	{
 		// send ALPHA FindNode packets to nodes we know, closest to target
 		const LAST_BIN: u32 = NODE_BINS - 1;
@@ -136,21 +137,21 @@ impl Discovery {
 		if head > 1 && tail != LAST_BIN {
 			while head != tail && head < NODE_BINS && count < BUCKET_SIZE
 			{
-				for n in buckets[head as usize].nodes.iter()
+				for n in &buckets[head as usize].nodes
 				{
 						if count < BUCKET_SIZE {
 							count += 1;
-							found.entry(Discovery::distance(target, &n)).or_insert(Vec::new()).push(n);
+							found.entry(Discovery::distance(target, &n)).or_insert_with(Vec::new).push(n);
 						}
 						else {
 							break;
 						}
 				}
 				if count < BUCKET_SIZE && tail != 0 {
-					for n in buckets[tail as usize].nodes.iter() {
+					for n in &buckets[tail as usize].nodes {
 						if count < BUCKET_SIZE {
 							count += 1;
-							found.entry(Discovery::distance(target, &n)).or_insert(Vec::new()).push(n);
+							found.entry(Discovery::distance(target, &n)).or_insert_with(Vec::new).push(n);
 						}
 						else {
 							break;
@@ -166,10 +167,10 @@ impl Discovery {
 		}
 		else if head < 2 {
 			while head < NODE_BINS && count < BUCKET_SIZE {
-				for n in buckets[head as usize].nodes.iter() {
+				for n in &buckets[head as usize].nodes {
 						if count < BUCKET_SIZE {
 							count += 1;
-							found.entry(Discovery::distance(target, &n)).or_insert(Vec::new()).push(n);
+							found.entry(Discovery::distance(target, &n)).or_insert_with(Vec::new).push(n);
 						}
 						else {
 							break;
@@ -180,10 +181,10 @@ impl Discovery {
 		}
 		else {
 			while tail > 0 && count < BUCKET_SIZE {
-				for n in buckets[tail as usize].nodes.iter() {
+				for n in &buckets[tail as usize].nodes {
 						if count < BUCKET_SIZE {
 							count += 1;
-							found.entry(Discovery::distance(target, &n)).or_insert(Vec::new()).push(n);
+							found.entry(Discovery::distance(target, &n)).or_insert_with(Vec::new).push(n);
 						}
 						else {
 							break;

util/src/network/error.rs

@@ -19,11 +19,17 @@ pub enum DisconnectReason
 }
 
 #[derive(Debug)]
+/// Network error.
 pub enum NetworkError {
+	/// Authentication error.
 	Auth,
+	/// Unrecognised protocol.
 	BadProtocol,
+	/// Peer not found.
 	PeerNotFound,
+	/// Peer is diconnected.
 	Disconnect(DisconnectReason),
+	/// Socket IO error.
 	Io(IoError),
 }
 

util/src/network/handshake.rs

@@ -1,3 +1,4 @@
+use std::sync::Arc;
 use mio::*;
 use mio::tcp::*;
 use hash::*;
@@ -10,6 +11,8 @@ use network::host::{HostInfo};
 use network::node::NodeId;
 use error::*;
 use network::error::NetworkError;
+use network::stats::NetworkStats;
+use io::{IoContext, StreamToken};
 
 #[derive(PartialEq, Eq, Debug)]
 enum HandshakeState {
@@ -33,8 +36,6 @@ pub struct Handshake {
 	state: HandshakeState,
 	/// Outgoing or incoming connection
 	pub originated: bool,
-	/// Disconnect timeout
-	idle_timeout: Option<Timeout>,
 	/// ECDH ephemeral
 	pub ecdhe: KeyPair,
 	/// Connection nonce
@@ -51,16 +52,16 @@ pub struct Handshake {
 
 const AUTH_PACKET_SIZE: usize = 307;
 const ACK_PACKET_SIZE: usize = 210;
+const HANDSHAKE_TIMEOUT: u64 = 30000;
 
 impl Handshake {
 	/// Create a new handshake object
-	pub fn new(token: Token, id: &NodeId, socket: TcpStream, nonce: &H256) -> Result<Handshake, UtilError> {
+	pub fn new(token: StreamToken, id: Option<&NodeId>, socket: TcpStream, nonce: &H256, stats: Arc<NetworkStats>) -> Result<Handshake, UtilError> {
 		Ok(Handshake {
-			id: id.clone(),
-			connection: Connection::new(token, socket),
+			id: if let Some(id) = id { id.clone()} else { NodeId::new() },
+			connection: Connection::new(token, socket, stats),
 			originated: false,
 			state: HandshakeState::New,
-			idle_timeout: None,
 			ecdhe: try!(KeyPair::create()),
 			nonce: nonce.clone(),
 			remote_public: Public::new(),
@@ -71,8 +72,9 @@ impl Handshake {
 	}
 
 	/// Start a handhsake
-	pub fn start(&mut self, host: &HostInfo, originated: bool) -> Result<(), UtilError> {
+	pub fn start<Message>(&mut self, io: &IoContext<Message>, host: &HostInfo, originated: bool) -> Result<(), UtilError> where Message: Send + Clone{
 		self.originated = originated;
+		io.register_timer(self.connection.token, HANDSHAKE_TIMEOUT).ok();
 		if originated {
 			try!(self.write_auth(host));
 		}
@@ -89,79 +91,90 @@ impl Handshake {
 	}
 
 	/// Readable IO handler. Drives the state change.
-	pub fn readable<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>, host: &HostInfo) -> Result<(), UtilError> {
-		self.idle_timeout.map(|t| event_loop.clear_timeout(t));
+	pub fn readable<Message>(&mut self, io: &IoContext<Message>, host: &HostInfo) -> Result<(), UtilError> where Message: Send + Clone {
+		io.clear_timer(self.connection.token).unwrap();
 		match self.state {
 			HandshakeState::ReadingAuth => {
-				match try!(self.connection.readable()) {
-					Some(data)  => {
-						try!(self.read_auth(host, &data));
-						try!(self.write_ack());
-					},
-					None => {}
+				if let Some(data) = try!(self.connection.readable()) {
+					try!(self.read_auth(host, &data));
+					try!(self.write_ack());
 				};
 			},
 			HandshakeState::ReadingAck => {
-				match try!(self.connection.readable()) {
-					Some(data)  => {
-						try!(self.read_ack(host, &data));
-						self.state = HandshakeState::StartSession;
-					},
-					None => {}
+				if let Some(data) = try!(self.connection.readable()) {
+					try!(self.read_ack(host, &data));
+					self.state = HandshakeState::StartSession;
 				};
 			},
+			HandshakeState::StartSession => {},
 			_ => { panic!("Unexpected state"); }
 		}
 		if self.state != HandshakeState::StartSession {
-			try!(self.connection.reregister(event_loop));
+			try!(io.update_registration(self.connection.token));
 		}
 		Ok(())
 	}
 
 	/// Writabe IO handler.
-	pub fn writable<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>, _host: &HostInfo) -> Result<(), UtilError> {
-		self.idle_timeout.map(|t| event_loop.clear_timeout(t));
+	pub fn writable<Message>(&mut self, io: &IoContext<Message>, _host: &HostInfo) -> Result<(), UtilError> where Message: Send + Clone {
+		io.clear_timer(self.connection.token).unwrap();
 		try!(self.connection.writable());
 		if self.state != HandshakeState::StartSession {
-			try!(self.connection.reregister(event_loop));
+			io.update_registration(self.connection.token).unwrap();
 		}
 		Ok(())
 	}
 
-	/// Register the IO handler with the event loop
-	pub fn register<Host:Handler<Timeout=Token>>(&mut self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
-		self.idle_timeout.map(|t| event_loop.clear_timeout(t));
-		self.idle_timeout = event_loop.timeout_ms(self.connection.token, 1800).ok();
-		try!(self.connection.register(event_loop));
+	/// Register the socket with the event loop
+	pub fn register_socket<Host:Handler<Timeout=Token>>(&self, reg: Token, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
+		try!(self.connection.register_socket(reg, event_loop));
+		Ok(())
+	}
+
+	pub fn update_socket<Host:Handler<Timeout=Token>>(&self, reg: Token, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
+		try!(self.connection.update_socket(reg, event_loop));
+		Ok(())
+	}
+
+	/// Delete registration
+	pub fn deregister_socket<Host:Handler>(&self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
+		try!(self.connection.deregister_socket(event_loop));
 		Ok(())
 	}
 
 	/// Parse, validate and confirm auth message
 	fn read_auth(&mut self, host: &HostInfo, data: &[u8]) -> Result<(), UtilError> {
 		trace!(target:"net", "Received handshake auth to {:?}", self.connection.socket.peer_addr());
-		assert!(data.len() == AUTH_PACKET_SIZE);
+		if data.len() != AUTH_PACKET_SIZE {
+			debug!(target:"net", "Wrong auth packet size");
+			return Err(From::from(NetworkError::BadProtocol));
+		}
 		self.auth_cipher = data.to_vec();
 		let auth = try!(ecies::decrypt(host.secret(), data));
 		let (sig, rest) = auth.split_at(65);
 		let (hepubk, rest) = rest.split_at(32);
 		let (pubk, rest) = rest.split_at(64);
 		let (nonce, _) = rest.split_at(32);
-		self.remote_public.clone_from_slice(pubk);
+		self.id.clone_from_slice(pubk);
 		self.remote_nonce.clone_from_slice(nonce);
-		let shared = try!(ecdh::agree(host.secret(), &self.remote_public));
+		let shared = try!(ecdh::agree(host.secret(), &self.id));
 		let signature = Signature::from_slice(sig);
 		let spub = try!(ec::recover(&signature, &(&shared ^ &self.remote_nonce)));
+		self.remote_public = spub.clone();
 		if &spub.sha3()[..] != hepubk {
 			trace!(target:"net", "Handshake hash mismath with {:?}", self.connection.socket.peer_addr());
 			return Err(From::from(NetworkError::Auth));
 		};
-		self.write_ack()
+		Ok(())
 	}
 
 	/// Parse and validate ack message
 	fn read_ack(&mut self, host: &HostInfo, data: &[u8]) -> Result<(), UtilError> {
 		trace!(target:"net", "Received handshake auth to {:?}", self.connection.socket.peer_addr());
-		assert!(data.len() == ACK_PACKET_SIZE);
+		if data.len() != ACK_PACKET_SIZE {
+			debug!(target:"net", "Wrong ack packet size");
+			return Err(From::from(NetworkError::BadProtocol));
+		}
 		self.ack_cipher = data.to_vec();
 		let ack = try!(ecies::decrypt(host.secret(), data));
 		self.remote_public.clone_from_slice(&ack[0..64]);

util/src/network/host.rs

@@ -1,8 +1,9 @@
-use std::mem;
 use std::net::{SocketAddr};
 use std::collections::{HashMap};
 use std::hash::{Hasher};
 use std::str::{FromStr};
+use std::sync::*;
+use std::ops::*;
 use mio::*;
 use mio::tcp::*;
 use mio::udp::*;
@@ -16,6 +17,7 @@ use error::*;
 use io::*;
 use network::NetworkProtocolHandler;
 use network::node::*;
+use network::stats::NetworkStats;
 
 type Slab<T> = ::slab::Slab<T, usize>;
 
@@ -27,24 +29,45 @@ const IDEAL_PEERS: u32 = 10;
 const MAINTENANCE_TIMEOUT: u64 = 1000;
 
 #[derive(Debug)]
-struct NetworkConfiguration {
-	listen_address: SocketAddr,
-	public_address: SocketAddr,
-	nat_enabled: bool,
-	discovery_enabled: bool,
-	pin: bool,
+/// Network service configuration
+pub struct NetworkConfiguration {
+	/// IP address to listen for incoming connections
+	pub listen_address: SocketAddr,
+	/// IP address to advertise
+	pub public_address: SocketAddr,
+	/// Enable NAT configuration
+	pub nat_enabled: bool,
+	/// Enable discovery
+	pub discovery_enabled: bool,
+	/// Pin to boot nodes only
+	pub pin: bool,
+	/// List of initial node addresses
+	pub boot_nodes: Vec<String>,
+	/// Use provided node key instead of default
+	pub use_secret: Option<Secret>,
 }
 
 impl NetworkConfiguration {
-	fn new() -> NetworkConfiguration {
+	/// Create a new instance of default settings.
+	pub fn new() -> NetworkConfiguration {
 		NetworkConfiguration {
 			listen_address: SocketAddr::from_str("0.0.0.0:30304").unwrap(),
 			public_address: SocketAddr::from_str("0.0.0.0:30304").unwrap(),
 			nat_enabled: true,
 			discovery_enabled: true,
 			pin: false,
+			boot_nodes: Vec::new(),
+			use_secret: None,
 		}
 	}
+
+	/// Create new default configuration with sepcified listen port.
+	pub fn new_with_port(port: u16) -> NetworkConfiguration {
+		let mut config = NetworkConfiguration::new();
+		config.listen_address = SocketAddr::from_str(&format!("0.0.0.0:{}", port)).unwrap();
+		config.public_address = SocketAddr::from_str(&format!("0.0.0.0:{}", port)).unwrap();
+		config
+	}
 }
 
 // Tokens
@@ -64,19 +87,25 @@ pub type PacketId = u8;
 pub type ProtocolId = &'static str;
 
 /// Messages used to communitate with the event loop from other threads.
-pub enum NetworkIoMessage<Message> where Message: Send {
+#[derive(Clone)]
+pub enum NetworkIoMessage<Message> where Message: Send + Sync + Clone {
 	/// Register a new protocol handler.
 	AddHandler {
-		handler: Option<Box<NetworkProtocolHandler<Message>+Send>>,
+		/// Handler shared instance.
+		handler: Arc<NetworkProtocolHandler<Message> + Sync>,
+		/// Protocol Id.
 		protocol: ProtocolId,
+		/// Supported protocol versions.
 		versions: Vec<u8>,
 	},
-	/// Send data over the network.
-	Send {
-		peer: PeerId,
-		packet_id: PacketId,
+	/// Register a new protocol timer
+	AddTimer {
+		/// Protocol Id.
 		protocol: ProtocolId,
-		data: Vec<u8>,
+		/// Timer token.
+		token: TimerToken,
+		/// Timer delay in milliseconds.
+		delay: u64,
 	},
 	/// User message
 	User(Message),
@@ -104,46 +133,45 @@ impl Encodable for CapabilityInfo {
 }
 
 /// IO access point. This is passed to all IO handlers and provides an interface to the IO subsystem.
-pub struct NetworkContext<'s, 'io, Message> where Message: Send + 'static, 'io: 's {
-	io: &'s mut IoContext<'io, NetworkIoMessage<Message>>,
+pub struct NetworkContext<'s, Message> where Message: Send + Sync + Clone + 'static, 's {
+	io: &'s IoContext<NetworkIoMessage<Message>>,
 	protocol: ProtocolId,
-	connections: &'s mut Slab<ConnectionEntry>,
-	timers: &'s mut HashMap<TimerToken, ProtocolId>,
+	connections: Arc<RwLock<Slab<SharedConnectionEntry>>>,
 	session: Option<StreamToken>,
 }
 
-impl<'s, 'io, Message> NetworkContext<'s, 'io, Message> where Message: Send + 'static, {
+impl<'s, Message> NetworkContext<'s, Message> where Message: Send + Sync + Clone + 'static, {
 	/// Create a new network IO access point. Takes references to all the data that can be updated within the IO handler.
-	fn new(io: &'s mut IoContext<'io, NetworkIoMessage<Message>>, 
+	fn new(io: &'s IoContext<NetworkIoMessage<Message>>, 
 		protocol: ProtocolId, 
-		session: Option<StreamToken>, connections: &'s mut Slab<ConnectionEntry>, 
-		timers: &'s mut HashMap<TimerToken, ProtocolId>) -> NetworkContext<'s, 'io, Message> {
+		session: Option<StreamToken>, connections: Arc<RwLock<Slab<SharedConnectionEntry>>>) -> NetworkContext<'s, Message> {
 		NetworkContext {
 			io: io,
 			protocol: protocol,
 			session: session,
 			connections: connections,
-			timers: timers,
 		}
 	}
 
 	/// Send a packet over the network to another peer.
-	pub fn send(&mut self, peer: PeerId, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError> {
-		match self.connections.get_mut(peer) {
-			Some(&mut ConnectionEntry::Session(ref mut s)) => {
-				s.send_packet(self.protocol, packet_id as u8, &data).unwrap_or_else(|e| {
-					warn!(target: "net", "Send error: {:?}", e);
-				}); //TODO: don't copy vector data
-			},
-			_ => {
-				warn!(target: "net", "Send: Peer does not exist");
+	pub fn send(&self, peer: PeerId, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError> {
+		if let Some(connection) = self.connections.read().unwrap().get(peer).cloned() {
+			match *connection.lock().unwrap().deref_mut() {
+				ConnectionEntry::Session(ref mut s) => {
+					s.send_packet(self.protocol, packet_id as u8, &data).unwrap_or_else(|e| {
+						warn!(target: "net", "Send error: {:?}", e);
+					}); //TODO: don't copy vector data
+				},
+				_ => warn!(target: "net", "Send: Peer is not connected yet")
 			}
+		} else  {
+			warn!(target: "net", "Send: Peer does not exist")
 		}
 		Ok(())
 	}
 
 	/// Respond to a current network message. Panics if no there is no packet in the context.
-	pub fn respond(&mut self, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError> {
+	pub fn respond(&self, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError> {
 		match self.session {
 			Some(session) => self.send(session, packet_id, data),
 			None => {
@@ -153,31 +181,28 @@ impl<'s, 'io, Message> NetworkContext<'s, 'io, Message> where Message: Send + 's
 	}
 
 	/// Disable current protocol capability for given peer. If no capabilities left peer gets disconnected.
-	pub fn disable_peer(&mut self, _peer: PeerId) {
+	pub fn disable_peer(&self, _peer: PeerId) {
 		//TODO: remove capability, disconnect if no capabilities left
 	}
 
-	/// Register a new IO timer. Returns a new timer token. 'NetworkProtocolHandler::timeout' will be called with the token.
-	pub fn register_timer(&mut self, ms: u64) -> Result<TimerToken, UtilError>{
-		match self.io.register_timer(ms) {
-			Ok(token) => {
-				self.timers.insert(token, self.protocol);
-				Ok(token)
-			},
-			e => e,
-		}
+	/// Register a new IO timer. 'IoHandler::timeout' will be called with the token.
+	pub fn register_timer(&self, token: TimerToken, ms: u64) -> Result<(), UtilError> {
+		self.io.message(NetworkIoMessage::AddTimer {
+			token: token,
+			delay: ms,
+			protocol: self.protocol,
+		});
+		Ok(())
 	}
 
 	/// Returns peer identification string
 	pub fn peer_info(&self, peer: PeerId) -> String {
-		match self.connections.get(peer) {
-			Some(&ConnectionEntry::Session(ref s)) => {
-				s.info.client_version.clone()
-			},
-			_ => {
-				"unknown".to_string()
+		if let Some(connection) = self.connections.read().unwrap().get(peer).cloned() {
+			if let ConnectionEntry::Session(ref s) = *connection.lock().unwrap().deref() {
+				return s.info.client_version.clone()
 			}
 		}
+		"unknown".to_owned()
 	}
 }
 
@@ -213,7 +238,7 @@ impl HostInfo {
 	/// Increments and returns connection nonce.
 	pub fn next_nonce(&mut self) -> H256 {
 		self.nonce = self.nonce.sha3();
-		return self.nonce.clone();
+		self.nonce.clone()
 	}
 }
 
@@ -222,66 +247,103 @@ enum ConnectionEntry {
 	Session(Session)
 }
 
-/// Root IO handler. Manages protocol handlers, IO timers and network connections.
-pub struct Host<Message> where Message: Send {
-	pub info: HostInfo,
-	udp_socket: UdpSocket,
-	listener: TcpListener,
-	connections: Slab<ConnectionEntry>,
-	timers: HashMap<TimerToken, ProtocolId>,
-	nodes: HashMap<NodeId, Node>,
-	handlers: HashMap<ProtocolId, Box<NetworkProtocolHandler<Message>>>,
+type SharedConnectionEntry = Arc<Mutex<ConnectionEntry>>;
+
+#[derive(Copy, Clone)]
+struct ProtocolTimer {
+	pub protocol: ProtocolId,
+	pub token: TimerToken, // Handler level token
 }
 
-impl<Message> Host<Message> where Message: Send {
-	pub fn new() -> Host<Message> {
-		let config = NetworkConfiguration::new();
+/// Root IO handler. Manages protocol handlers, IO timers and network connections.
+pub struct Host<Message> where Message: Send + Sync + Clone {
+	pub info: RwLock<HostInfo>,
+	udp_socket: Mutex<UdpSocket>,
+	tcp_listener: Mutex<TcpListener>,
+	connections: Arc<RwLock<Slab<SharedConnectionEntry>>>,
+	nodes: RwLock<HashMap<NodeId, Node>>,
+	handlers: RwLock<HashMap<ProtocolId, Arc<NetworkProtocolHandler<Message>>>>,
+	timers: RwLock<HashMap<TimerToken, ProtocolTimer>>,
+	timer_counter: RwLock<usize>,
+	stats: Arc<NetworkStats>,
+}
+
+impl<Message> Host<Message> where Message: Send + Sync + Clone {
+	/// Create a new instance
+	pub fn new(config: NetworkConfiguration) -> Host<Message> {
 		let addr = config.listen_address;
 		// Setup the server socket
-		let listener = TcpListener::bind(&addr).unwrap();
+		let tcp_listener = TcpListener::bind(&addr).unwrap();
 		let udp_socket = UdpSocket::bound(&addr).unwrap();
-		Host::<Message> {
-			info: HostInfo {
-				keys: KeyPair::create().unwrap(),
+		let mut host = Host::<Message> {
+			info: RwLock::new(HostInfo {
+				keys: if let Some(ref secret) = config.use_secret { KeyPair::from_secret(secret.clone()).unwrap() } else { KeyPair::create().unwrap() },
 				config: config,
 				nonce: H256::random(),
 				protocol_version: 4,
-				client_version: "parity".to_string(),
+				client_version: "parity".to_owned(),
 				listen_port: 0,
 				capabilities: Vec::new(),
-			},
-			udp_socket: udp_socket,
-			listener: listener,
-			connections: Slab::new_starting_at(FIRST_CONNECTION, MAX_CONNECTIONS),
-			timers: HashMap::new(),
-			nodes: HashMap::new(),
-			handlers: HashMap::new(),
+			}),
+			udp_socket: Mutex::new(udp_socket),
+			tcp_listener: Mutex::new(tcp_listener),
+			connections: Arc::new(RwLock::new(Slab::new_starting_at(FIRST_CONNECTION, MAX_CONNECTIONS))),
+			nodes: RwLock::new(HashMap::new()),
+			handlers: RwLock::new(HashMap::new()),
+			timers: RwLock::new(HashMap::new()),
+			timer_counter: RwLock::new(LAST_CONNECTION + 1),
+			stats: Arc::new(NetworkStats::default()),
+		};
+		let port = host.info.read().unwrap().config.listen_address.port();
+		host.info.write().unwrap().deref_mut().listen_port = port;
+
+		/*
+		match ::ifaces::Interface::get_all().unwrap().into_iter().filter(|x| x.kind == ::ifaces::Kind::Packet && x.addr.is_some()).next() {
+		Some(iface) => config.public_address = iface.addr.unwrap(),
+		None => warn!("No public network interface"),
+		*/
+
+		let boot_nodes = host.info.read().unwrap().config.boot_nodes.clone();
+		for n in boot_nodes {
+			host.add_node(&n);
 		}
+		host
 	}
 
-	fn add_node(&mut self, id: &str) {
+	pub fn stats(&self) -> Arc<NetworkStats> {
+		self.stats.clone()
+	}
+
+	pub fn add_node(&mut self, id: &str) {
 		match Node::from_str(id) {
 			Err(e) => { warn!("Could not add node: {:?}", e); },
 			Ok(n) => {
-				self.nodes.insert(n.id.clone(), n);
+				self.nodes.write().unwrap().insert(n.id.clone(), n);
 			}
 		}
 	}
 
-	fn maintain_network(&mut self, io: &mut IoContext<NetworkIoMessage<Message>>) {
+	pub fn client_version(&self) -> String {
+		self.info.read().unwrap().client_version.clone()
+	}
+
+	pub fn client_id(&self) -> NodeId {
+		self.info.read().unwrap().id().clone()
+	}
+
+	fn maintain_network(&self, io: &IoContext<NetworkIoMessage<Message>>) {
 		self.connect_peers(io);
-		io.event_loop.timeout_ms(Token(IDLE), MAINTENANCE_TIMEOUT).unwrap();
 	}
 
 	fn have_session(&self, id: &NodeId) -> bool {
-		self.connections.iter().any(|e| match e { &ConnectionEntry::Session(ref s) => s.info.id.eq(&id), _ => false  })
+		self.connections.read().unwrap().iter().any(|e| match *e.lock().unwrap().deref() { ConnectionEntry::Session(ref s) => s.info.id.eq(&id), _ => false  })
 	}
 
 	fn connecting_to(&self, id: &NodeId) -> bool {
-		self.connections.iter().any(|e| match e { &ConnectionEntry::Handshake(ref h) => h.id.eq(&id), _ => false  })
+		self.connections.read().unwrap().iter().any(|e| match *e.lock().unwrap().deref() { ConnectionEntry::Handshake(ref h) => h.id.eq(&id), _ => false  })
 	}
 
-	fn connect_peers(&mut self, io: &mut IoContext<NetworkIoMessage<Message>>) {
+	fn connect_peers(&self, io: &IoContext<NetworkIoMessage<Message>>) {
 		struct NodeInfo {
 			id: NodeId,
 			peer_type: PeerType
@@ -292,18 +354,19 @@ impl<Message> Host<Message> where Message: Send {
 		let mut req_conn = 0;
 		//TODO: use nodes from discovery here
 		//for n in self.node_buckets.iter().flat_map(|n| &n.nodes).map(|id| NodeInfo { id: id.clone(), peer_type: self.nodes.get(id).unwrap().peer_type}) {
-		for n in self.nodes.values().map(|n| NodeInfo { id: n.id.clone(), peer_type: n.peer_type }) {
+		let pin = self.info.read().unwrap().deref().config.pin;
+		for n in self.nodes.read().unwrap().values().map(|n| NodeInfo { id: n.id.clone(), peer_type: n.peer_type }) {
 			let connected = self.have_session(&n.id) || self.connecting_to(&n.id);
 			let required = n.peer_type == PeerType::Required;
 			if connected && required {
 				req_conn += 1;
 			}
-			else if !connected && (!self.info.config.pin || required) {
+			else if !connected && (!pin || required) {
 				to_connect.push(n);
 			}
 		}
 
-		for n in to_connect.iter() {
+		for n in &to_connect {
 			if n.peer_type == PeerType::Required {
 				if req_conn < IDEAL_PEERS {
 					self.connect_peer(&n.id, io);
@@ -312,13 +375,12 @@ impl<Message> Host<Message> where Message: Send {
 			}
 		}
 
-		if !self.info.config.pin
-		{
+		if !pin {
 			let pending_count = 0; //TODO:
 			let peer_count = 0;
 			let mut open_slots = IDEAL_PEERS - peer_count  - pending_count + req_conn;
 			if open_slots > 0 {
-				for n in to_connect.iter() {
+				for n in &to_connect {
 					if n.peer_type == PeerType::Optional && open_slots > 0 {
 						open_slots -= 1;
 						self.connect_peer(&n.id, io);
@@ -328,23 +390,26 @@ impl<Message> Host<Message> where Message: Send {
 		}
 	}
 
-	fn connect_peer(&mut self, id: &NodeId, io: &mut IoContext<NetworkIoMessage<Message>>) {
+	#[allow(single_match)]
+	fn connect_peer(&self, id: &NodeId, io: &IoContext<NetworkIoMessage<Message>>) {
 		if self.have_session(id)
 		{
 			warn!("Aborted connect. Node already connected.");
 			return;
 		}
-		if self.connecting_to(id)
-		{
+		if self.connecting_to(id) {
 			warn!("Aborted connect. Node already connecting.");
 			return;
 		}
 
 		let socket = {
-			let node = self.nodes.get_mut(id).unwrap();
-			node.last_attempted = Some(::time::now());
-
-			match TcpStream::connect(&node.endpoint.address) {
+			let address = {
+				let mut nodes = self.nodes.write().unwrap();
+				let node = nodes.get_mut(id).unwrap();
+				node.last_attempted = Some(::time::now());
+				node.endpoint.address
+			};
+			match TcpStream::connect(&address) {
 				Ok(socket) => socket,
 				Err(_) => {
 					warn!("Cannot connect to node");
@@ -352,225 +417,203 @@ impl<Message> Host<Message> where Message: Send {
 				}
 			}
 		};
+		self.create_connection(socket, Some(id), io);
+	}
 
-		let nonce = self.info.next_nonce();
-		match self.connections.insert_with(|token| ConnectionEntry::Handshake(Handshake::new(Token(token), id, socket, &nonce).expect("Can't create handshake"))) {
-			Some(token) => {
-				match self.connections.get_mut(token) {
-					Some(&mut ConnectionEntry::Handshake(ref mut h)) => {
-						h.start(&self.info, true)
-							.and_then(|_| h.register(io.event_loop))
-							.unwrap_or_else (|e| {
-								debug!(target: "net", "Handshake create error: {:?}", e);
-							});
-					},
-					_ => {}
-				}
-			},
-			None => { warn!("Max connections reached") }
+	#[allow(block_in_if_condition_stmt)]
+	fn create_connection(&self, socket: TcpStream, id: Option<&NodeId>, io: &IoContext<NetworkIoMessage<Message>>) {
+		let nonce = self.info.write().unwrap().next_nonce();
+		let mut connections = self.connections.write().unwrap();
+		if connections.insert_with(|token| {
+			let mut handshake = Handshake::new(token, id, socket, &nonce, self.stats.clone()).expect("Can't create handshake");
+			handshake.start(io, &self.info.read().unwrap(), id.is_some()).and_then(|_| io.register_stream(token)).unwrap_or_else (|e| {
+				debug!(target: "net", "Handshake create error: {:?}", e);
+			});
+			Arc::new(Mutex::new(ConnectionEntry::Handshake(handshake)))
+		}).is_none() {
+			warn!("Max connections reached");
 		}
 	}
 
-
-	fn accept(&mut self, _io: &mut IoContext<NetworkIoMessage<Message>>) {
+	fn accept(&self, io: &IoContext<NetworkIoMessage<Message>>) {
 		trace!(target: "net", "accept");
+		loop {
+			let socket = match self.tcp_listener.lock().unwrap().accept() {
+				Ok(None) => break,
+				Ok(Some((sock, _addr))) => sock,
+				Err(e) => {
+					warn!("Error accepting connection: {:?}", e);
+					break
+				},
+			};
+			self.create_connection(socket, None, io);
+		}
+		io.update_registration(TCP_ACCEPT).expect("Error registering TCP listener");
 	}
 
-	fn connection_writable<'s>(&'s mut self, token: StreamToken, io: &mut IoContext<'s, NetworkIoMessage<Message>>) {
-		let mut kill = false;
+	#[allow(single_match)]
+	fn connection_writable(&self, token: StreamToken, io: &IoContext<NetworkIoMessage<Message>>) {
 		let mut create_session = false;
-		match self.connections.get_mut(token) {
-			Some(&mut ConnectionEntry::Handshake(ref mut h)) => {
-				h.writable(io.event_loop, &self.info).unwrap_or_else(|e| {
-					debug!(target: "net", "Handshake write error: {:?}", e);
-					kill = true;
-				});
-				create_session = h.done();
-			},
-			Some(&mut ConnectionEntry::Session(ref mut s)) => {
-				s.writable(io.event_loop, &self.info).unwrap_or_else(|e| {
-					debug!(target: "net", "Session write error: {:?}", e);
-					kill = true;
-				});
+		let mut kill = false;
+		if let Some(connection) = self.connections.read().unwrap().get(token).cloned() {
+			match *connection.lock().unwrap().deref_mut() {
+				ConnectionEntry::Handshake(ref mut h) => {
+					match h.writable(io, &self.info.read().unwrap()) {
+						Err(e) => {
+							debug!(target: "net", "Handshake write error: {:?}", e);
+							kill = true;
+						},
+						Ok(_) => ()
+					}
+					if h.done() {
+						create_session = true;
+					}
+				},
+				ConnectionEntry::Session(ref mut s) => {
+					match s.writable(io, &self.info.read().unwrap()) {
+						Err(e) => {
+							debug!(target: "net", "Session write error: {:?}", e);
+							kill = true;
+						},
+						Ok(_) => ()
+					}
+					io.update_registration(token).unwrap_or_else(|e| debug!(target: "net", "Session registration error: {:?}", e));
+				}
 			}
-			_ => {
-				warn!(target: "net", "Received event for unknown connection");
-			}
-		}
+		} 
 		if kill {
-			self.kill_connection(token, io);
+			self.kill_connection(token, io); //TODO: mark connection as dead an check in kill_connection
 			return;
 		} else if create_session {
 			self.start_session(token, io);
-		}
-		match self.connections.get_mut(token) {
-			Some(&mut ConnectionEntry::Session(ref mut s)) => {
-				s.reregister(io.event_loop).unwrap_or_else(|e| debug!(target: "net", "Session registration error: {:?}", e));
-			},
-			_ => (),
+			io.update_registration(token).unwrap_or_else(|e| debug!(target: "net", "Session registration error: {:?}", e));
 		}
 	}
 
-	fn connection_closed<'s>(&'s mut self, token: TimerToken, io: &mut IoContext<'s, NetworkIoMessage<Message>>) {
+	fn connection_closed(&self, token: TimerToken, io: &IoContext<NetworkIoMessage<Message>>) {
 		self.kill_connection(token, io);
 	}
 
-	fn connection_readable<'s>(&'s mut self, token: StreamToken, io: &mut IoContext<'s, NetworkIoMessage<Message>>) {
-		let mut kill = false;
-		let mut create_session = false;
+	fn connection_readable(&self, token: StreamToken, io: &IoContext<NetworkIoMessage<Message>>) {
 		let mut ready_data: Vec<ProtocolId> = Vec::new();
 		let mut packet_data: Option<(ProtocolId, PacketId, Vec<u8>)> = None;
-		match self.connections.get_mut(token) {
-			Some(&mut ConnectionEntry::Handshake(ref mut h)) => {
-				h.readable(io.event_loop, &self.info).unwrap_or_else(|e| {
-					debug!(target: "net", "Handshake read error: {:?}", e);
-					kill = true;
-				});
-				create_session = h.done();
-			},
-			Some(&mut ConnectionEntry::Session(ref mut s)) => {
-				let sd = { s.readable(io.event_loop, &self.info).unwrap_or_else(|e| {
-					debug!(target: "net", "Session read error: {:?}", e);
-					kill = true;
-					SessionData::None
-				}) };
-				match sd {
-					SessionData::Ready => {
-						for (p, _) in self.handlers.iter_mut() {
-							if s.have_capability(p)  {
-								ready_data.push(p);
+		let mut create_session = false;
+		let mut kill = false;
+		if let Some(connection) = self.connections.read().unwrap().get(token).cloned() {
+			match *connection.lock().unwrap().deref_mut() {
+				ConnectionEntry::Handshake(ref mut h) => {
+					if let Err(e) = h.readable(io, &self.info.read().unwrap()) {
+						debug!(target: "net", "Handshake read error: {:?}", e);
+						kill = true;
+					}
+					if h.done() {
+						create_session = true;
+					}
+				},
+				ConnectionEntry::Session(ref mut s) => {
+					match s.readable(io, &self.info.read().unwrap()) {
+						Err(e) => {
+							debug!(target: "net", "Handshake read error: {:?}", e);
+							kill = true;
+						},
+						Ok(SessionData::Ready) => {
+							for (p, _) in self.handlers.read().unwrap().iter() {
+								if s.have_capability(p)  {
+									ready_data.push(p);
+								}
 							}
-						}
-					},
-					SessionData::Packet {
-						data,
-						protocol,
-						packet_id,
-					} => {
-						match self.handlers.get_mut(protocol) {
-							None => { warn!(target: "net", "No handler found for protocol: {:?}", protocol) },
-							Some(_) => packet_data = Some((protocol, packet_id, data)),
-						}
-					},
-					SessionData::None => {},
-				}
-			}
-			_ => {
-				warn!(target: "net", "Received event for unknown connection");
-			}
-		}
-		if kill {
-			self.kill_connection(token, io);
-			return;
-		}
-		if create_session {
-			self.start_session(token, io);
-		}
-		for p in ready_data {
-			let mut h = self.handlers.get_mut(p).unwrap();
-			h.connected(&mut NetworkContext::new(io, p, Some(token), &mut self.connections, &mut self.timers), &token);
-		}
-		if let Some((p, packet_id, data)) = packet_data {
-			let mut h = self.handlers.get_mut(p).unwrap();
-			h.read(&mut NetworkContext::new(io, p, Some(token), &mut self.connections, &mut self.timers), &token, packet_id, &data[1..]);
-		}
-
-		match self.connections.get_mut(token) {
-			Some(&mut ConnectionEntry::Session(ref mut s)) => {
-				s.reregister(io.event_loop).unwrap_or_else(|e| debug!(target: "net", "Session registration error: {:?}", e));
-			},
-			_ => (),
-		}
-	}
-
-	fn start_session(&mut self, token: StreamToken, io: &mut IoContext<NetworkIoMessage<Message>>) {
-		let info = &self.info;
-		// TODO: use slab::replace_with (currently broken)
-		/*
-		match self.connections.remove(token) {
-			Some(ConnectionEntry::Handshake(h)) => {
-				match Session::new(h, io.event_loop, info) {
-					Ok(session) => {
-						assert!(token == self.connections.insert(ConnectionEntry::Session(session)).ok().unwrap());
-					},
-					Err(e) => {
-						debug!(target: "net", "Session construction error: {:?}", e);
+						},
+						Ok(SessionData::Packet {
+							data,
+							protocol,
+							packet_id,
+						}) => {
+							match self.handlers.read().unwrap().get(protocol) {
+								None => { warn!(target: "net", "No handler found for protocol: {:?}", protocol) },
+								Some(_) => packet_data = Some((protocol, packet_id, data)),
+							}
+						},
+						Ok(SessionData::None) => {},
 					}
 				}
-			},
-			_ => panic!("Error updating slab with session")
-		}*/
-		self.connections.replace_with(token, |c| {
-			match c {
-				ConnectionEntry::Handshake(h) => Session::new(h, io.event_loop, info)
-					.map(|s| Some(ConnectionEntry::Session(s)))
-					.unwrap_or_else(|e| {
-						debug!(target: "net", "Session construction error: {:?}", e);
-						None
-					}),
-					_ => { panic!("No handshake to create a session from"); }
 			}
-		}).expect("Error updating slab with session");
+		} 
+		if kill {
+			self.kill_connection(token, io); //TODO: mark connection as dead an check in kill_connection
+			return;
+		} else if create_session {
+			self.start_session(token, io);
+			io.update_registration(token).unwrap_or_else(|e| debug!(target: "net", "Session registration error: {:?}", e));
+		}
+		for p in ready_data {
+			let h = self.handlers.read().unwrap().get(p).unwrap().clone();
+			h.connected(&NetworkContext::new(io, p, Some(token), self.connections.clone()), &token);
+		}
+		if let Some((p, packet_id, data)) = packet_data {
+			let h = self.handlers.read().unwrap().get(p).unwrap().clone();
+			h.read(&NetworkContext::new(io, p, Some(token), self.connections.clone()), &token, packet_id, &data[1..]);
+		}
+		io.update_registration(token).unwrap_or_else(|e| debug!(target: "net", "Token registration error: {:?}", e));
 	}
 
-	fn connection_timeout<'s>(&'s mut self, token: StreamToken, io: &mut IoContext<'s, NetworkIoMessage<Message>>) {
+	fn start_session(&self, token: StreamToken, io: &IoContext<NetworkIoMessage<Message>>) {
+		let mut connections = self.connections.write().unwrap();
+		connections.replace_with(token, |c| {
+			match Arc::try_unwrap(c).ok().unwrap().into_inner().unwrap() {
+				ConnectionEntry::Handshake(h) => {
+					let session = Session::new(h, io, &self.info.read().unwrap()).expect("Session creation error");
+					io.update_registration(token).expect("Error updating session registration");
+					self.stats.inc_sessions();
+					Some(Arc::new(Mutex::new(ConnectionEntry::Session(session))))
+				},
+				_ => { None } // handshake expired
+			}
+		}).ok();
+	}
+
+	fn connection_timeout(&self, token: StreamToken, io: &IoContext<NetworkIoMessage<Message>>) {
 		self.kill_connection(token, io)
 	}
 
-	fn kill_connection<'s>(&'s mut self, token: StreamToken, io: &mut IoContext<'s, NetworkIoMessage<Message>>) {
+	fn kill_connection(&self, token: StreamToken, io: &IoContext<NetworkIoMessage<Message>>) {
 		let mut to_disconnect: Vec<ProtocolId> = Vec::new();
-		let mut remove = true;
-		match self.connections.get_mut(token) {
-			Some(&mut ConnectionEntry::Handshake(_)) => (), // just abandon handshake
-			Some(&mut ConnectionEntry::Session(ref mut s)) if s.is_ready() => {
-				for (p, _) in self.handlers.iter_mut() {
-					if s.have_capability(p)  {
-						to_disconnect.push(p);
-					}
+		{
+			let mut connections = self.connections.write().unwrap();
+			if let Some(connection) = connections.get(token).cloned() {
+				match *connection.lock().unwrap().deref_mut() {
+					ConnectionEntry::Handshake(_) => {
+						connections.remove(token);
+					},
+					ConnectionEntry::Session(ref mut s) if s.is_ready() => {
+						for (p, _) in self.handlers.read().unwrap().iter() {
+							if s.have_capability(p)  {
+								to_disconnect.push(p);
+							}
+						}
+						connections.remove(token);
+					},
+					_ => {},
 				}
-			},
-			_ => {
-				remove = false;
-			},
+			}
+			io.deregister_stream(token).expect("Error deregistering stream");
 		}
 		for p in to_disconnect {
-			let mut h = self.handlers.get_mut(p).unwrap();
-			h.disconnected(&mut NetworkContext::new(io, p, Some(token), &mut self.connections, &mut self.timers), &token);
-		}
-		if remove {
-			self.connections.remove(token);
+			let h = self.handlers.read().unwrap().get(p).unwrap().clone();
+			h.disconnected(&NetworkContext::new(io, p, Some(token), self.connections.clone()), &token);
 		}
 	}
 }
 
-impl<Message> IoHandler<NetworkIoMessage<Message>> for Host<Message> where Message: Send + 'static {
+impl<Message> IoHandler<NetworkIoMessage<Message>> for Host<Message> where Message: Send + Sync + Clone + 'static {
 	/// Initialize networking
-	fn initialize(&mut self, io: &mut IoContext<NetworkIoMessage<Message>>) {
-		/*
-		match ::ifaces::Interface::get_all().unwrap().into_iter().filter(|x| x.kind == ::ifaces::Kind::Packet && x.addr.is_some()).next() {
-		Some(iface) => config.public_address = iface.addr.unwrap(),
-		None => warn!("No public network interface"),
-		*/
-
-		// Start listening for incoming connections
-		io.event_loop.register(&self.listener, Token(TCP_ACCEPT), EventSet::readable(), PollOpt::edge()).unwrap();
-		io.event_loop.timeout_ms(Token(IDLE), MAINTENANCE_TIMEOUT).unwrap();
-		// open the udp socket
-		io.event_loop.register(&self.udp_socket, Token(NODETABLE_RECEIVE), EventSet::readable(), PollOpt::edge()).unwrap();
-		io.event_loop.timeout_ms(Token(NODETABLE_MAINTAIN), 7200).unwrap();
-		let port = self.info.config.listen_address.port();
-		self.info.listen_port = port;
-
-		self.add_node("enode://a9a921de2ff09a9a4d38b623c67b2d6b477a8e654ae95d874750cbbcb31b33296496a7b4421934e2629269e180823e52c15c2b19fc59592ec51ffe4f2de76ed7@127.0.0.1:30303");
-/*		// GO bootnodes
-		self.add_node("enode://a979fb575495b8d6db44f750317d0f4622bf4c2aa3365d6af7c284339968eef29b69ad0dce72a4d8db5ebb4968de0e3bec910127f134779fbcb0cb6d3331163c@52.16.188.185:30303"); // IE
-		self.add_node("enode://de471bccee3d042261d52e9bff31458daecc406142b401d4cd848f677479f73104b9fdeb090af9583d3391b7f10cb2ba9e26865dd5fca4fcdc0fb1e3b723c786@54.94.239.50:30303");  // BR
-		self.add_node("enode://1118980bf48b0a3640bdba04e0fe78b1add18e1cd99bf22d53daac1fd9972ad650df52176e7c7d89d1114cfef2bc23a2959aa54998a46afcf7d91809f0855082@52.74.57.123:30303");  // SG
-		// ETH/DEV cpp-ethereum (poc-9.ethdev.com)
-		self.add_node("enode://979b7fa28feeb35a4741660a16076f1943202cb72b6af70d327f053e248bab9ba81760f39d0701ef1d8f89cc1fbd2cacba0710a12cd5314d5e0c9021aa3637f9@5.1.83.226:30303");*/
+	fn initialize(&self, io: &IoContext<NetworkIoMessage<Message>>) {
+		io.register_stream(TCP_ACCEPT).expect("Error registering TCP listener");
+		io.register_stream(NODETABLE_RECEIVE).expect("Error registering UDP listener");
+		io.register_timer(IDLE, MAINTENANCE_TIMEOUT).expect("Error registering Network idle timer");
+		//io.register_timer(NODETABLE_MAINTAIN, 7200);
 	}
 
-	fn stream_hup<'s>(&'s mut self, io: &mut IoContext<'s, NetworkIoMessage<Message>>, stream: StreamToken) {
+	fn stream_hup(&self, io: &IoContext<NetworkIoMessage<Message>>, stream: StreamToken) {
 		trace!(target: "net", "Hup: {}", stream);
 		match stream {
 			FIRST_CONNECTION ... LAST_CONNECTION => self.connection_closed(stream, io),
@@ -578,7 +621,7 @@ impl<Message> IoHandler<NetworkIoMessage<Message>> for Host<Message> where Messa
 		};
 	}
 
-	fn stream_readable<'s>(&'s mut self, io: &mut IoContext<'s, NetworkIoMessage<Message>>, stream: StreamToken) {
+	fn stream_readable(&self, io: &IoContext<NetworkIoMessage<Message>>, stream: StreamToken) {
 		match stream {
 			FIRST_CONNECTION ... LAST_CONNECTION => self.connection_readable(stream, io),
 			NODETABLE_RECEIVE => {},
@@ -587,65 +630,115 @@ impl<Message> IoHandler<NetworkIoMessage<Message>> for Host<Message> where Messa
 		}
 	}
 
-	fn stream_writable<'s>(&'s mut self, io: &mut IoContext<'s, NetworkIoMessage<Message>>, stream: StreamToken) {
+	fn stream_writable(&self, io: &IoContext<NetworkIoMessage<Message>>, stream: StreamToken) {
 		match stream {
 			FIRST_CONNECTION ... LAST_CONNECTION => self.connection_writable(stream, io),
+			NODETABLE_RECEIVE => {},
 			_ => panic!("Received unknown writable token"),
 		}
 	}
 
-	fn timeout<'s>(&'s mut self, io: &mut IoContext<'s, NetworkIoMessage<Message>>, token: TimerToken) {
+	fn timeout(&self, io: &IoContext<NetworkIoMessage<Message>>, token: TimerToken) {
 		match token {
 			IDLE => self.maintain_network(io),
 			FIRST_CONNECTION ... LAST_CONNECTION => self.connection_timeout(token, io),
 			NODETABLE_DISCOVERY => {},
 			NODETABLE_MAINTAIN => {},
-			_ => match self.timers.get_mut(&token).map(|p| *p) {
-					Some(protocol) => match self.handlers.get_mut(protocol) {
-							None => { warn!(target: "net", "No handler found for protocol: {:?}", protocol) },
-							Some(h) => { h.timeout(&mut NetworkContext::new(io, protocol, Some(token), &mut self.connections, &mut self.timers), token); }
-					},
-					None => {} // time not registerd through us
+			_ => match self.timers.read().unwrap().get(&token).cloned() {
+				Some(timer) => match self.handlers.read().unwrap().get(timer.protocol).cloned() {
+						None => { warn!(target: "net", "No handler found for protocol: {:?}", timer.protocol) },
+						Some(h) => { h.timeout(&NetworkContext::new(io, timer.protocol, None, self.connections.clone()), timer.token); }
+				},
+				None => { warn!("Unknown timer token: {}", token); } // timer is not registerd through us
 			}
 		}
 	}
 
-	fn message<'s>(&'s mut self, io: &mut IoContext<'s, NetworkIoMessage<Message>>, message: &'s mut NetworkIoMessage<Message>) {
-		match message {
-			&mut NetworkIoMessage::AddHandler {
-				ref mut handler,
+	fn message(&self, io: &IoContext<NetworkIoMessage<Message>>, message: &NetworkIoMessage<Message>) {
+		match *message {
+			NetworkIoMessage::AddHandler {
+				ref handler,
 				ref protocol,
 				ref versions
 			} => {
-				let mut h = mem::replace(handler, None).unwrap();
-				h.initialize(&mut NetworkContext::new(io, protocol, None, &mut self.connections, &mut self.timers));
-				self.handlers.insert(protocol, h);
+				let h = handler.clone();
+				h.initialize(&NetworkContext::new(io, protocol, None, self.connections.clone()));
+				self.handlers.write().unwrap().insert(protocol, h);
+				let mut info = self.info.write().unwrap();
 				for v in versions {
-					self.info.capabilities.push(CapabilityInfo { protocol: protocol, version: *v, packet_count:0 });
+					info.capabilities.push(CapabilityInfo { protocol: protocol, version: *v, packet_count:0 });
 				}
 			},
-			&mut NetworkIoMessage::Send {
-				ref peer,
-				ref packet_id,
+			NetworkIoMessage::AddTimer {
 				ref protocol,
-				ref data,
+				ref delay,
+				ref token,
 			} => {
-				match self.connections.get_mut(*peer as usize) {
-					Some(&mut ConnectionEntry::Session(ref mut s)) => {
-						s.send_packet(protocol, *packet_id as u8, &data).unwrap_or_else(|e| {
-							warn!(target: "net", "Send error: {:?}", e);
-						}); //TODO: don't copy vector data
-					},
-					_ => {
-						warn!(target: "net", "Send: Peer does not exist");
-					}
-				}
+				let handler_token = {
+					let mut timer_counter = self.timer_counter.write().unwrap();
+					let counter = timer_counter.deref_mut();
+					let handler_token = *counter;
+					*counter += 1;
+					handler_token
+				};
+				self.timers.write().unwrap().insert(handler_token, ProtocolTimer { protocol: protocol, token: *token });
+				io.register_timer(handler_token, *delay).expect("Error registering timer");
 			},
-			&mut NetworkIoMessage::User(ref message) => {
-				for (p, h) in self.handlers.iter_mut() {
-					h.message(&mut NetworkContext::new(io, p, None, &mut self.connections, &mut self.timers), &message);
+			NetworkIoMessage::User(ref message) => {
+				for (p, h) in self.handlers.read().unwrap().iter() {
+					h.message(&NetworkContext::new(io, p, None, self.connections.clone()), &message);
 				}
 			}
 		}
 	}
+
+	fn register_stream(&self, stream: StreamToken, reg: Token, event_loop: &mut EventLoop<IoManager<NetworkIoMessage<Message>>>) {
+		match stream {
+			FIRST_CONNECTION ... LAST_CONNECTION => {
+				if let Some(connection) = self.connections.read().unwrap().get(stream).cloned() {
+					match *connection.lock().unwrap().deref() {
+						ConnectionEntry::Handshake(ref h) => h.register_socket(reg, event_loop).expect("Error registering socket"),
+						ConnectionEntry::Session(_) => warn!("Unexpected session stream registration")
+					}
+				} else {} // expired
+			}
+			NODETABLE_RECEIVE => event_loop.register(self.udp_socket.lock().unwrap().deref(), Token(NODETABLE_RECEIVE), EventSet::all(), PollOpt::edge()).expect("Error registering stream"),
+			TCP_ACCEPT => event_loop.register(self.tcp_listener.lock().unwrap().deref(), Token(TCP_ACCEPT), EventSet::all(), PollOpt::edge()).expect("Error registering stream"),
+			_ => warn!("Unexpected stream registration")
+		}
+	}
+
+	fn deregister_stream(&self, stream: StreamToken, event_loop: &mut EventLoop<IoManager<NetworkIoMessage<Message>>>) {
+		match stream {
+			FIRST_CONNECTION ... LAST_CONNECTION => {
+				let mut connections = self.connections.write().unwrap();
+				if let Some(connection) = connections.get(stream).cloned() {
+					match *connection.lock().unwrap().deref() {
+						ConnectionEntry::Handshake(ref h) => h.deregister_socket(event_loop).expect("Error deregistering socket"),
+						ConnectionEntry::Session(ref s) => s.deregister_socket(event_loop).expect("Error deregistering session socket"),
+					}
+					connections.remove(stream);
+				} 
+			},
+			NODETABLE_RECEIVE => event_loop.deregister(self.udp_socket.lock().unwrap().deref()).unwrap(),
+			TCP_ACCEPT => event_loop.deregister(self.tcp_listener.lock().unwrap().deref()).unwrap(),
+			_ => warn!("Unexpected stream deregistration")
+		}
+	}
+
+	fn update_stream(&self, stream: StreamToken, reg: Token, event_loop: &mut EventLoop<IoManager<NetworkIoMessage<Message>>>) {
+		match stream {
+			FIRST_CONNECTION ... LAST_CONNECTION => {
+				if let Some(connection) = self.connections.read().unwrap().get(stream).cloned() {
+					match *connection.lock().unwrap().deref() {
+						ConnectionEntry::Handshake(ref h) => h.update_socket(reg, event_loop).expect("Error updating socket"),
+						ConnectionEntry::Session(ref s) => s.update_socket(reg, event_loop).expect("Error updating socket"),
+					}
+				} else {} // expired
+			}
+			NODETABLE_RECEIVE => event_loop.reregister(self.udp_socket.lock().unwrap().deref(), Token(NODETABLE_RECEIVE), EventSet::all(), PollOpt::edge()).expect("Error reregistering stream"),
+			TCP_ACCEPT => event_loop.reregister(self.tcp_listener.lock().unwrap().deref(), Token(TCP_ACCEPT), EventSet::all(), PollOpt::edge()).expect("Error reregistering stream"),
+			_ => warn!("Unexpected stream update")
+		}
+	}
 }

util/src/network/mod.rs

@@ -1,5 +1,4 @@
-/// Network and general IO module.
-///
+/// Network and general IO module. 
 /// Example usage for craeting a network service and adding an IO handler:
 ///
 /// ```rust
@@ -8,39 +7,40 @@
 ///
 /// struct MyHandler;
 ///
+/// #[derive(Clone)]
 /// struct MyMessage {
 /// 	data: u32
 /// }
 ///
 /// impl NetworkProtocolHandler<MyMessage> for MyHandler {
-///		fn initialize(&mut self, io: &mut NetworkContext<MyMessage>) {
-///			io.register_timer(1000);
+///		fn initialize(&self, io: &NetworkContext<MyMessage>) {
+///			io.register_timer(0, 1000);
 ///		}
 ///
-///		fn read(&mut self, io: &mut NetworkContext<MyMessage>, peer: &PeerId, packet_id: u8, data: &[u8]) {
+///		fn read(&self, io: &NetworkContext<MyMessage>, peer: &PeerId, packet_id: u8, data: &[u8]) {
 ///			println!("Received {} ({} bytes) from {}", packet_id, data.len(), peer);
 ///		}
 ///
-///		fn connected(&mut self, io: &mut NetworkContext<MyMessage>, peer: &PeerId) {
+///		fn connected(&self, io: &NetworkContext<MyMessage>, peer: &PeerId) {
 ///			println!("Connected {}", peer);
 ///		}
 ///
-///		fn disconnected(&mut self, io: &mut NetworkContext<MyMessage>, peer: &PeerId) {
+///		fn disconnected(&self, io: &NetworkContext<MyMessage>, peer: &PeerId) {
 ///			println!("Disconnected {}", peer);
 ///		}
 ///
-///		fn timeout(&mut self, io: &mut NetworkContext<MyMessage>, timer: TimerToken) {
+///		fn timeout(&self, io: &NetworkContext<MyMessage>, timer: TimerToken) {
 ///			println!("Timeout {}", timer);
 ///		}
 ///
-///		fn message(&mut self, io: &mut NetworkContext<MyMessage>, message: &MyMessage) {
+///		fn message(&self, io: &NetworkContext<MyMessage>, message: &MyMessage) {
 ///			println!("Message {}", message.data);
 ///		}
 /// }
 ///
 /// fn main () {
-/// 	let mut service = NetworkService::<MyMessage>::start().expect("Error creating network service");
-/// 	service.register_protocol(Box::new(MyHandler), "myproto", &[1u8]);
+/// 	let mut service = NetworkService::<MyMessage>::start(NetworkConfiguration::new()).expect("Error creating network service");
+/// 	service.register_protocol(Arc::new(MyHandler), "myproto", &[1u8]);
 ///
 /// 	// Wait for quit condition
 /// 	// ...
@@ -55,38 +55,38 @@ mod discovery;
 mod service;
 mod error;
 mod node;
+mod stats;
 
-/// TODO [arkpar] Please document me
-pub type PeerId = host::PeerId;
-/// TODO [arkpar] Please document me
-pub type PacketId = host::PacketId;
-/// TODO [arkpar] Please document me
-pub type NetworkContext<'s,'io,  Message> = host::NetworkContext<'s, 'io, Message>;
-/// TODO [arkpar] Please document me
-pub type NetworkService<Message> = service::NetworkService<Message>;
-/// TODO [arkpar] Please document me
-pub type NetworkIoMessage<Message> = host::NetworkIoMessage<Message>;
+#[cfg(test)]
+mod tests;
+
+pub use network::host::PeerId;
+pub use network::host::PacketId;
+pub use network::host::NetworkContext;
+pub use network::service::NetworkService;
+pub use network::host::NetworkIoMessage;
 pub use network::host::NetworkIoMessage::User as UserMessage;
-/// TODO [arkpar] Please document me
-pub type NetworkError = error::NetworkError;
+pub use network::error::NetworkError;
+pub use network::host::NetworkConfiguration;
+pub use network::stats::NetworkStats;
 
-use io::*;
+use io::TimerToken;
 
 /// Network IO protocol handler. This needs to be implemented for each new subprotocol.
 /// All the handler function are called from within IO event loop.
 /// `Message` is the type for message data.
-pub trait NetworkProtocolHandler<Message>: Send where Message: Send {
+pub trait NetworkProtocolHandler<Message>: Sync + Send where Message: Send + Sync + Clone {
 	/// Initialize the handler
-	fn initialize(&mut self, _io: &mut NetworkContext<Message>) {}
+	fn initialize(&self, _io: &NetworkContext<Message>) {}
 	/// Called when new network packet received.
-	fn read(&mut self, io: &mut NetworkContext<Message>, peer: &PeerId, packet_id: u8, data: &[u8]);
+	fn read(&self, io: &NetworkContext<Message>, peer: &PeerId, packet_id: u8, data: &[u8]);
 	/// Called when new peer is connected. Only called when peer supports the same protocol.
-	fn connected(&mut self, io: &mut NetworkContext<Message>, peer: &PeerId);
+	fn connected(&self, io: &NetworkContext<Message>, peer: &PeerId);
 	/// Called when a previously connected peer disconnects.
-	fn disconnected(&mut self, io: &mut NetworkContext<Message>, peer: &PeerId);
+	fn disconnected(&self, io: &NetworkContext<Message>, peer: &PeerId);
 	/// Timer function called after a timeout created with `NetworkContext::timeout`.
-	fn timeout(&mut self, _io: &mut NetworkContext<Message>, _timer: TimerToken) {}
+	fn timeout(&self, _io: &NetworkContext<Message>, _timer: TimerToken) {}
 	/// Called when a broadcasted message is received. The message can only be sent from a different IO handler.
-	fn message(&mut self, _io: &mut NetworkContext<Message>, _message: &Message) {}
+	fn message(&self, _io: &NetworkContext<Message>, _message: &Message) {}
 }
 

util/src/network/node.rs

@@ -20,14 +20,16 @@ pub struct NodeEndpoint {
 	pub udp_port: u16
 }
 
-impl NodeEndpoint {
+impl FromStr for NodeEndpoint {
+	type Err = UtilError;
+
 	/// Create endpoint from string. Performs name resolution if given a host name.
 	fn from_str(s: &str) -> Result<NodeEndpoint, UtilError> {
 		let address = s.to_socket_addrs().map(|mut i| i.next());
 		match address {
 			Ok(Some(a)) => Ok(NodeEndpoint {
 				address: a,
-				address_str: s.to_string(),
+				address_str: s.to_owned(),
 				udp_port: a.port()
 			}),
 			Ok(_) => Err(UtilError::AddressResolve(None)),

util/src/network/service.rs

@@ -1,45 +1,39 @@
+use std::sync::*;
 use error::*;
-use network::{NetworkProtocolHandler};
+use network::{NetworkProtocolHandler, NetworkConfiguration};
 use network::error::{NetworkError};
-use network::host::{Host, NetworkIoMessage, PeerId, PacketId, ProtocolId};
+use network::host::{Host, NetworkIoMessage, ProtocolId};
+use network::stats::{NetworkStats};
 use io::*;
 
 /// IO Service with networking
 /// `Message` defines a notification data type.
-pub struct NetworkService<Message> where Message: Send + 'static {
+pub struct NetworkService<Message> where Message: Send + Sync + Clone + 'static {
 	io_service: IoService<NetworkIoMessage<Message>>,
 	host_info: String,
+	stats: Arc<NetworkStats>
 }
 
-impl<Message> NetworkService<Message> where Message: Send + 'static {
+impl<Message> NetworkService<Message> where Message: Send + Sync + Clone + 'static {
 	/// Starts IO event loop
-	pub fn start() -> Result<NetworkService<Message>, UtilError> {
+	pub fn start(config: NetworkConfiguration) -> Result<NetworkService<Message>, UtilError> {
 		let mut io_service = try!(IoService::<NetworkIoMessage<Message>>::start());
-		let host = Box::new(Host::new());
-		let host_info = host.info.client_version.clone();
-		info!("NetworkService::start(): id={:?}", host.info.id());
+		let host = Arc::new(Host::new(config));
+		let stats = host.stats().clone();
+		let host_info = host.client_version();
+		info!("NetworkService::start(): id={:?}", host.client_id());
 		try!(io_service.register_handler(host));
 		Ok(NetworkService {
 			io_service: io_service,
 			host_info: host_info,
+			stats: stats,
 		})
 	}
 
-	/// Send a message over the network. Normaly `HostIo::send` should be used. This can be used from non-io threads.
-	pub fn send(&mut self, peer: &PeerId, packet_id: PacketId, protocol: ProtocolId, data: &[u8]) -> Result<(), NetworkError> {
-		try!(self.io_service.send_message(NetworkIoMessage::Send {
-			peer: *peer,
-			packet_id: packet_id,
-			protocol: protocol,
-			data: data.to_vec()
-		}));
-		Ok(())
-	}
-
 	/// Regiter a new protocol handler with the event loop.
-	pub fn register_protocol(&mut self, handler: Box<NetworkProtocolHandler<Message>+Send>, protocol: ProtocolId, versions: &[u8]) -> Result<(), NetworkError> {
+	pub fn register_protocol(&mut self, handler: Arc<NetworkProtocolHandler<Message>+Send + Sync>, protocol: ProtocolId, versions: &[u8]) -> Result<(), NetworkError> {
 		try!(self.io_service.send_message(NetworkIoMessage::AddHandler {
-			handler: Some(handler),
+			handler: handler,
 			protocol: protocol,
 			versions: versions.to_vec(),
 		}));
@@ -56,6 +50,9 @@ impl<Message> NetworkService<Message> where Message: Send + 'static {
 		&mut self.io_service
 	}
 
-
+	/// Returns underlying io service.
+	pub fn stats(&self) -> &NetworkStats {
+		&self.stats
+	}
 }
 

util/src/network/session.rs

@@ -4,6 +4,7 @@ use rlp::*;
 use network::connection::{EncryptedConnection, Packet};
 use network::handshake::Handshake;
 use error::*;
+use io::{IoContext};
 use network::error::{NetworkError, DisconnectReason};
 use network::host::*;
 use network::node::NodeId;
@@ -84,7 +85,7 @@ const PACKET_LAST: u8 = 0x7f;
 
 impl Session {
 	/// Create a new session out of comepleted handshake. Consumes handshake object.
-	pub fn new<Host:Handler<Timeout=Token>>(h: Handshake, event_loop: &mut EventLoop<Host>, host: &HostInfo) -> Result<Session, UtilError> {
+	pub fn new<Message>(h: Handshake, _io: &IoContext<Message>, host: &HostInfo) -> Result<Session, UtilError> where Message: Send + Sync + Clone {
 		let id = h.id.clone();
 		let connection = try!(EncryptedConnection::new(h));
 		let mut session = Session {
@@ -99,7 +100,6 @@ impl Session {
 		};
 		try!(session.write_hello(host));
 		try!(session.write_ping());
-		try!(session.connection.register(event_loop));
 		Ok(session)
 	}
 
@@ -109,16 +109,16 @@ impl Session {
 	}
 
 	/// Readable IO handler. Returns packet data if available.
-	pub fn readable<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>, host: &HostInfo) -> Result<SessionData, UtilError> {
-		match try!(self.connection.readable(event_loop)) {
+	pub fn readable<Message>(&mut self, io: &IoContext<Message>, host: &HostInfo) -> Result<SessionData, UtilError>  where Message: Send + Sync + Clone {
+		match try!(self.connection.readable(io)) {
 			Some(data) => Ok(try!(self.read_packet(data, host))),
 			None => Ok(SessionData::None)
 		}
 	}
 
 	/// Writable IO handler. Sends pending packets.
-	pub fn writable<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>, _host: &HostInfo) -> Result<(), UtilError> {
-		self.connection.writable(event_loop)
+	pub fn writable<Message>(&mut self, io: &IoContext<Message>, _host: &HostInfo) -> Result<(), UtilError> where Message: Send + Sync + Clone {
+		self.connection.writable(io)
 	}
 
 	/// Checks if peer supports given capability
@@ -127,8 +127,13 @@ impl Session {
 	}
 
 	/// Update registration with the event loop. Should be called at the end of the IO handler.
-	pub fn reregister<Host:Handler>(&mut self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
-		self.connection.reregister(event_loop)
+	pub fn update_socket<Host:Handler>(&self, reg:Token, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
+		self.connection.update_socket(reg, event_loop)
+	}
+
+	/// Delete registration
+	pub fn deregister_socket<Host:Handler>(&self, event_loop: &mut EventLoop<Host>) -> Result<(), UtilError> {
+		self.connection.deregister_socket(event_loop)
 	}
 
 	/// Send a protocol packet to peer.
@@ -182,7 +187,7 @@ impl Session {
 				// map to protocol
 				let protocol = self.info.capabilities[i].protocol;
 				let pid = packet_id - self.info.capabilities[i].id_offset;
-				return Ok(SessionData::Packet { data: packet.data, protocol: protocol, packet_id: pid } )
+				Ok(SessionData::Packet { data: packet.data, protocol: protocol, packet_id: pid } )
 			},
 			_ => {
 				debug!(target: "net", "Unkown packet: {:?}", packet_id);
@@ -212,7 +217,7 @@ impl Session {
 		// Intersect with host capabilities
 		// Leave only highset mutually supported capability version
 		let mut caps: Vec<SessionCapabilityInfo> = Vec::new();
-		for hc in host.capabilities.iter() {
+		for hc in &host.capabilities {
 			if peer_caps.iter().any(|c| c.protocol == hc.protocol && c.version == hc.version) {
 				caps.push(SessionCapabilityInfo {
 					protocol: hc.protocol,

util/src/network/stats.rs

@@ -0,0 +1,51 @@
+//! Network Statistics
+use std::sync::atomic::*;
+
+/// Network statistics structure
+#[derive(Default, Debug)]
+pub struct NetworkStats {
+	/// Bytes received
+	recv: AtomicUsize,
+	/// Bytes sent
+	send: AtomicUsize,
+	/// Total number of sessions created
+	sessions: AtomicUsize,
+}
+
+impl NetworkStats {
+	/// Increase bytes received.
+	#[inline]
+	pub fn inc_recv(&self, size: usize) {
+		self.recv.fetch_add(size, Ordering::Relaxed);
+	}
+
+	/// Increase bytes sent.
+	#[inline]
+	pub fn inc_send(&self, size: usize) {
+		self.send.fetch_add(size, Ordering::Relaxed);
+	}
+
+	/// Increase number of sessions.
+	#[inline]
+	pub fn inc_sessions(&self) {
+		self.sessions.fetch_add(1, Ordering::Relaxed);
+	}
+
+	/// Get bytes sent.
+	#[inline]
+	pub fn send(&self) -> usize {
+		self.send.load(Ordering::Relaxed)
+	}
+
+	/// Get bytes received.
+	#[inline]
+	pub fn recv(&self) -> usize {
+		self.recv.load(Ordering::Relaxed)
+	}
+
+	/// Get total number of sessions created.
+	#[inline]
+	pub fn sessions(&self) -> usize {
+		self.sessions.load(Ordering::Relaxed)
+	}
+}

util/src/network/tests.rs

@@ -0,0 +1,103 @@
+use std::sync::atomic::{AtomicBool, Ordering as AtomicOrdering};
+use std::thread;
+use std::time::*;
+use common::*;
+use network::*;
+use io::TimerToken;
+use crypto::KeyPair;
+
+pub struct TestProtocol {
+	pub packet: Mutex<Bytes>,
+	pub got_timeout: AtomicBool,
+}
+
+impl Default for TestProtocol {
+	fn default() -> Self {
+		TestProtocol { 
+			packet: Mutex::new(Vec::new()), 
+			got_timeout: AtomicBool::new(false), 
+		}
+	}
+}
+
+#[derive(Clone)]
+pub struct TestProtocolMessage {
+	payload: u32,
+}
+
+impl TestProtocol {
+	/// Creates and register protocol with the network service
+	pub fn register(service: &mut NetworkService<TestProtocolMessage>) -> Arc<TestProtocol> {
+		let handler = Arc::new(TestProtocol::default());
+		service.register_protocol(handler.clone(), "test", &[42u8, 43u8]).expect("Error registering test protocol handler");
+		handler
+	}
+
+	pub fn got_packet(&self) -> bool {
+		self.packet.lock().unwrap().deref()[..] == b"hello"[..]
+	}
+
+	pub fn got_timeout(&self) -> bool {
+		self.got_timeout.load(AtomicOrdering::Relaxed)
+	}
+}
+
+impl NetworkProtocolHandler<TestProtocolMessage> for TestProtocol {
+	fn initialize(&self, io: &NetworkContext<TestProtocolMessage>) {
+		io.register_timer(0, 10).unwrap();
+	}
+
+	fn read(&self, _io: &NetworkContext<TestProtocolMessage>, _peer: &PeerId, packet_id: u8, data: &[u8]) {
+		assert_eq!(packet_id, 33);
+		self.packet.lock().unwrap().extend(data);
+	}
+
+	fn connected(&self, io: &NetworkContext<TestProtocolMessage>, _peer: &PeerId) {
+		io.respond(33, "hello".to_owned().into_bytes()).unwrap();
+	}
+
+	fn disconnected(&self, _io: &NetworkContext<TestProtocolMessage>, _peer: &PeerId) {
+	}
+
+	/// Timer function called after a timeout created with `NetworkContext::timeout`.
+	fn timeout(&self, _io: &NetworkContext<TestProtocolMessage>, timer: TimerToken) {
+		assert_eq!(timer, 0);
+		self.got_timeout.store(true, AtomicOrdering::Relaxed);
+	}
+}
+
+
+#[test]
+fn test_net_service() {
+	let mut service = NetworkService::<TestProtocolMessage>::start(NetworkConfiguration::new()).expect("Error creating network service");
+	service.register_protocol(Arc::new(TestProtocol::default()), "myproto", &[1u8]).unwrap();
+}
+
+#[test]
+fn test_net_connect() {
+	let key1 = KeyPair::create().unwrap();
+	let mut config1 = NetworkConfiguration::new_with_port(30344);
+	config1.use_secret = Some(key1.secret().clone());
+	config1.boot_nodes = vec![ ];
+	let mut config2 = NetworkConfiguration::new_with_port(30345);
+	config2.boot_nodes = vec![ format!("enode://{}@127.0.0.1:30344", key1.public().hex()) ];
+	let mut service1 = NetworkService::<TestProtocolMessage>::start(config1).unwrap();
+	let mut service2 = NetworkService::<TestProtocolMessage>::start(config2).unwrap();
+	let handler1 = TestProtocol::register(&mut service1);
+	let handler2 = TestProtocol::register(&mut service2);
+	while !handler1.got_packet() && !handler2.got_packet() {
+		thread::sleep(Duration::from_millis(50));
+	}
+	assert!(service1.stats().sessions() >= 1);
+	assert!(service2.stats().sessions() >= 1);
+}
+
+#[test]
+fn test_net_timeout() {
+	let config = NetworkConfiguration::new_with_port(30346);
+	let mut service = NetworkService::<TestProtocolMessage>::start(config).unwrap();
+	let handler = TestProtocol::register(&mut service);
+	while !handler.got_timeout() {
+		thread::sleep(Duration::from_millis(50));
+	}
+}

util/src/overlaydb.rs

@@ -169,7 +169,7 @@ impl HashDB for OverlayDB {
 		match k {
 			Some(&(ref d, rc)) if rc > 0 => Some(d),
 			_ => {
-				let memrc = k.map(|&(_, rc)| rc).unwrap_or(0);
+				let memrc = k.map_or(0, |&(_, rc)| rc);
 				match self.payload(key) {
 					Some(x) => {
 						let (d, rc) = x;
@@ -194,16 +194,11 @@ impl HashDB for OverlayDB {
 		match k {
 			Some(&(_, rc)) if rc > 0 => true,
 			_ => {
-				let memrc = k.map(|&(_, rc)| rc).unwrap_or(0);
+				let memrc = k.map_or(0, |&(_, rc)| rc);
 				match self.payload(key) {
 					Some(x) => {
 						let (_, rc) = x;
-						if rc as i32 + memrc > 0 {
-							true
-						}
-						else {
-							false
-						}
+						rc as i32 + memrc > 0
 					}
 					// Replace above match arm with this once https://github.com/rust-lang/rust/issues/15287 is done.
 					//Some((d, rc)) if rc + memrc > 0 => true,

util/src/rlp/rlperrors.rs

@@ -7,6 +7,8 @@ use bytes::FromBytesError;
 pub enum DecoderError {
 	/// TODO [debris] Please document me
 	FromBytesError(FromBytesError),
+	/// Given data has additional bytes at the end of the valid RLP fragment.
+	RlpIsTooBig,
 	/// TODO [debris] Please document me
 	RlpIsTooShort,
 	/// TODO [debris] Please document me
@@ -21,6 +23,8 @@ pub enum DecoderError {
 	RlpListLenWithZeroPrefix,
 	/// TODO [debris] Please document me
 	RlpInvalidIndirection,
+	/// Returned when declared length is inconsistent with data specified after
+	RlpInconsistentLengthAndData
 }
 
 impl StdError for DecoderError {