Merge pull request #198 from ethcore/io

Mutithreaded IO

Cargo.toml

@@ -20,6 +20,7 @@ time = "0.1"
 evmjit = { path = "rust-evmjit", optional = true }
 ethash = { path = "ethash" }
 num_cpus = "0.2"
+ctrlc = "1.0"
 clippy = "*" # Always newest, since we use nightly
 
 [features]

ethash/src/lib.rs

@@ -30,13 +30,15 @@ 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
+		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)
 	}
 }

src/bin/client/main.rs

@@ -3,17 +3,18 @@ extern crate ethcore;
 extern crate rustc_serialize;
 extern crate log;
 extern crate env_logger;
+extern crate ctrlc;
 
-use std::io::stdin;
 use std::env;
 use log::{LogLevelFilter};
 use env_logger::LogBuilder;
+use ctrlc::CtrlC;
 use util::*;
 use ethcore::client::*;
-use ethcore::service::ClientService;
+use ethcore::service::{ClientService, NetSyncMessage};
 use ethcore::ethereum;
 use ethcore::blockchain::CacheSize;
-use ethcore::sync::*;
+use ethcore::sync::EthSync;
 
 fn setup_log() {
 	let mut builder = LogBuilder::new();
@@ -30,41 +31,56 @@ 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() });
+	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");
-	loop {
-		let mut cmd = String::new();
-		stdin().read_line(&mut cmd).unwrap();
-		if cmd == "quit\n" || cmd == "exit\n" || cmd == "q\n" {
-			break;
-		}
-	}
+
+	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();
 }
 
-#[derive(Default, Debug)]
 struct Informant {
-	chain_info: Option<BlockChainInfo>,
-	cache_info: Option<CacheSize>,
-	report: Option<ClientReport>,
+	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(&mut self, client: &Client) {
+	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, &self.cache_info, &self.report) {
-			println!("[ {} {} ]---[ {} blk/s | {} tx/s | {} gas/s  //···{}···//  {} ({}) bl  {} ({}) ex ]",
+		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),
-				0, // TODO: peers
+
+				sync_info.num_active_peers,
+				sync_info.num_peers,
+				sync_info.blocks_received,
+				queue_info.queue_size,
+
 				cache_info.blocks,
 				cache_info.blocks as isize - last_cache_info.blocks as isize,
 				cache_info.block_details,
@@ -72,28 +88,28 @@ impl Informant {
 			);
 		}
 
-		self.chain_info = Some(chain_info);
-		self.cache_info = Some(cache_info);
-		self.report = Some(report);
+		*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<RwLock<Client>>,
-	timer: TimerToken,
+	client: Arc<Client>,
+	sync: Arc<EthSync>,
 	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 initialize(&self, io: &IoContext<NetSyncMessage>) { 
+		io.register_timer(INFO_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());
+	fn timeout(&self, _io: &IoContext<NetSyncMessage>, timer: TimerToken) {
+		if INFO_TIMER == timer {
+			self.info.tick(&self.client, &self.sync);
 		}
 	}
 }

src/block_queue.rs

@@ -1,12 +1,23 @@
+//! 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
+	pub queue_size: usize,
+}
 
 /// A queue of blocks. Sits between network or other I/O and the BlockChain.
 /// Sorts them ready for blockchain insertion.
@@ -63,14 +74,15 @@ impl BlockQueue {
 		let deleting = Arc::new(AtomicBool::new(false));
 
 		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 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))
+				.expect("Error starting block verification thread"));
 		}
 		BlockQueue {
 			engine: engine,
@@ -204,7 +216,7 @@ 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 +227,19 @@ 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 {
+		BlockQueueInfo {
+			full: false,
+			queue_size: self.verification.lock().unwrap().unverified.len(),
+		}
+	}
 }
 
 impl Drop for BlockQueue {
@@ -234,7 +257,7 @@ impl Drop for BlockQueue {
 mod tests {
 	use util::*;
 	use spec::*;
-	use queue::*;
+	use block_queue::*;
 
 	#[test]
 	fn test_block_queue() {

src/blockchain.rs

@@ -341,19 +341,19 @@ 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 {
@@ -408,7 +408,7 @@ 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();
@@ -419,6 +419,8 @@ 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();
@@ -426,7 +428,7 @@ 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();
@@ -458,7 +460,7 @@ 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
@@ -466,7 +468,7 @@ 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
@@ -493,7 +495,7 @@ impl BlockChain {
 			total_difficulty: total_difficulty
 		};
 
-		(batch, Some(best_block))
+		(batch, Some(best_block), details)
 	}
 
 	/// Returns true if transaction is known.

src/client.rs

@@ -6,8 +6,8 @@ use error::*;
 use header::BlockNumber;
 use spec::Spec;
 use engine::Engine;
-use queue::BlockQueue;
-use sync::NetSyncMessage;
+use block_queue::{BlockQueue, BlockQueueInfo};
+use service::NetSyncMessage;
 use env_info::LastHashes;
 use verification::*;
 use block::*;
@@ -46,13 +46,6 @@ 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;
 
@@ -95,13 +88,13 @@ 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;
@@ -132,19 +125,21 @@ 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> {
+	pub fn new(spec: Spec, path: &Path, message_channel: IoChannel<NetSyncMessage> ) -> Result<Arc<Client>, Error> {
 		let chain = Arc::new(RwLock::new(BlockChain::new(&spec.genesis_block(), path)));
 		let mut opts = Options::new();
-		opts.create_if_missing(true);
 		opts.set_max_open_files(256);
+		opts.create_if_missing(true);
 		/*opts.set_use_fsync(false);
 		opts.set_bytes_per_sync(8388608);
 		opts.set_disable_data_sync(false);
@@ -164,37 +159,40 @@ 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");
 			}
+		}
+		let state_db = JournalDB::new_with_arc(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(()),
+		}))
 	}
 
 	/// 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>) {
 		let mut bad = HashSet::new();
-		let blocks = self.queue.drain(128); 
+		let _import_lock = self.import_lock.lock();
+		let blocks = self.block_queue.write().unwrap().drain(128); 
 		if blocks.is_empty() {
 			return;
 		}
 
 		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;
 			}
@@ -202,7 +200,7 @@ 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;
 			};
@@ -210,7 +208,7 @@ impl Client {
 				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;
 				},
@@ -228,18 +226,19 @@ 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());
+					self.block_queue.write().unwrap().mark_as_bad(&header.hash());
 					return;
 				}
 			};
 			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());
+				self.block_queue.write().unwrap().mark_as_bad(&header.hash());
 				return;
 			}
 
@@ -252,12 +251,16 @@ impl Client {
 					return;
 				}
 			}
-			self.report.accrue_block(&block);
-
+			self.report.write().unwrap().accrue_block(&block);
 			trace!(target: "client", "Imported #{} ({})", header.number(), header.hash());
 		}
 	}
 
+	/// Clear cached state overlay 
+	pub fn clear_state(&self, hash: &H256) {
+		self.uncommited_states.write().unwrap().remove(hash);
+	}
+
 	/// Get info on the cache.
 	pub fn cache_info(&self) -> CacheSize {
 		self.chain.read().unwrap().cache_size()
@@ -265,7 +268,7 @@ impl Client {
 
 	/// Get the report.
 	pub fn report(&self) -> ClientReport {
-		self.report.clone()
+		self.report.read().unwrap().clone()
 	}
 
 	/// Tick the client.
@@ -328,21 +331,20 @@ 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/lib.rs

@@ -151,6 +151,5 @@ 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/service.rs

@@ -5,10 +5,23 @@ 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 {
@@ -20,9 +33,9 @@ impl ClientService {
 		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));
@@ -30,6 +43,7 @@ impl ClientService {
 		Ok(ClientService {
 			net_service: net_service,
 			client: client,
+			sync: sync,
 		})
 	}
 
@@ -39,25 +53,45 @@ impl ClientService {
 	}
 
 	/// 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 timeout(&self, _io: &IoContext<NetSyncMessage>, timer: TimerToken) {
+		if timer == CLIENT_TICK_TIMER {
+			self.client.tick();
+		}
 	}
 
 	#[allow(match_ref_pats)]
-	fn message<'s>(&'s mut self, _io: &mut IoContext<'s, NetSyncMessage>, net_message: &'s mut NetSyncMessage) {
-		if let &mut UserMessage(ref mut message) = net_message {
-			if let &mut SyncMessage::BlockVerified= message {
-				self.client.write().unwrap().import_verified_blocks();
+	#[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/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(),
 		}
 	}
 
@@ -425,6 +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);
 			}
 		}
@@ -541,7 +551,7 @@ 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;
 		}
@@ -950,7 +960,7 @@ 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(&mut self) -> &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(&mut self) -> &mut BlockChainClient {
+	fn chain(&self) -> &BlockChainClient {
 		self.chain
 	}
 

src/sync/mod.rs

@@ -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/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 {
@@ -50,12 +52,12 @@ impl TestBlockChainClient {
 
 impl BlockChainClient for TestBlockChainClient {
 	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 +66,30 @@ impl BlockChainClient for TestBlockChainClient {
 	}
 
 	fn block(&self, h: &H256) -> Option<Bytes> {
-		self.blocks.get(h).cloned()
+		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_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 +112,14 @@ 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 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 +131,44 @@ 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());
+		if number == self.numbers.read().unwrap().len() {
+			*self.difficulty.write().unwrap().deref_mut() += header.difficulty;
+			mem::replace(self.last_hash.write().unwrap().deref_mut(), header.hash());
+			self.blocks.write().unwrap().insert(header.hash(), b);
+			self.numbers.write().unwrap().insert(number, header.hash());
 			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(header.hash(), b.to_vec());
 		}
 		Ok(())
 	}
 
-	fn queue_status(&self) -> BlockQueueStatus {
-		BlockQueueStatus {
+	fn queue_info(&self) -> BlockQueueInfo {
+		BlockQueueInfo {
 			full: false,
+			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 +211,7 @@ impl<'p> SyncIo for TestIo<'p> {
 		Ok(())
 	}
 
-	fn chain(&mut self) -> &mut BlockChainClient {
+	fn chain(&self) -> &BlockChainClient {
 		self.chain
 	}
 }
@@ -272,7 +275,7 @@ impl TestNet {
 				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));
 		}
 	}
 
@@ -297,7 +300,7 @@ 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]
@@ -310,7 +313,7 @@ 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]
@@ -326,9 +329,9 @@ 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);
 }

util/Cargo.toml

@@ -22,6 +22,7 @@ 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" }
 clippy = "*" # Always newest, since we use nightly

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 +57,63 @@ 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>>) {}
 }
 
 /// 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 +121,7 @@ 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 +1,229 @@
+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,
+	},
+	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(())
+	}
+
+	/// 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 &mut self.handlers {
-				h.stream_hup(&mut IoContext::new(event_loop, &mut self.timers), token.as_usize());
-			}
-		}
-		else if events.is_readable() {
-			for h in &mut self.handlers {
-				h.stream_readable(&mut IoContext::new(event_loop, &mut self.timers), token.as_usize());
-			}
-		}
-		else if events.is_writable() {
-			for h in &mut self.handlers {
-				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 &mut self.handlers {
-					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 &mut self.handlers {
-					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 &mut self.handlers {
-					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::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 +231,19 @@ 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 +252,31 @@ 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 +291,7 @@ 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 +310,10 @@ 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();

util/src/lib.rs

@@ -54,6 +54,7 @@ extern crate crypto as rcrypto;
 extern crate secp256k1;
 extern crate arrayvec;
 extern crate elastic_array;
+extern crate crossbeam;
 
 /// TODO [Gav Wood] Please document me
 pub mod standard;

util/src/network/connection.rs

@@ -1,5 +1,5 @@
 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::*;
@@ -7,6 +7,7 @@ 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 crypto;
@@ -17,11 +18,12 @@ 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
@@ -45,14 +47,14 @@ 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) -> 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(),
 		}
 	}
 
@@ -132,20 +134,19 @@ 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);
+	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| {
+			error!("Failed to register {:?}, {:?}", reg, e);
 			Err(e)
 		})
 	}
 
 	/// 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);
+	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| {
+			error!("Failed to reregister {:?}, {:?}", reg, e);
 			Err(e)
 		})
 	}
@@ -182,8 +183,6 @@ 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 +191,7 @@ 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 +226,7 @@ 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 +235,6 @@ impl EncryptedConnection {
 			egress_mac: egress_mac,
 			ingress_mac: ingress_mac,
 			read_state: EncryptedConnectionState::Header,
-			idle_timeout: None,
 			protocol_id: 0,
 			payload_len: 0
 		})
@@ -337,13 +336,14 @@ 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 => {
 				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 => {
@@ -360,24 +360,15 @@ 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));
-		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));
+	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(())
 	}
 }

util/src/network/discovery.rs

@@ -141,7 +141,7 @@ impl Discovery {
 				{
 						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;
@@ -151,7 +151,7 @@ impl Discovery {
 					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;
@@ -170,7 +170,7 @@ impl Discovery {
 				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;
@@ -184,7 +184,7 @@ impl Discovery {
 				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

@@ -10,6 +10,7 @@ use network::host::{HostInfo};
 use network::node::NodeId;
 use error::*;
 use network::error::NetworkError;
+use io::{IoContext, StreamToken};
 
 #[derive(PartialEq, Eq, Debug)]
 enum HandshakeState {
@@ -33,8 +34,6 @@ 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 +50,16 @@ 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: &NodeId, socket: TcpStream, nonce: &H256) -> Result<Handshake, UtilError> {
 		Ok(Handshake {
 			id: id.clone(),
 			connection: Connection::new(token, socket),
 			originated: false,
 			state: HandshakeState::New,
-			idle_timeout: None,
 			ecdhe: try!(KeyPair::create()),
 			nonce: nonce.clone(),
 			remote_public: Public::new(),
@@ -71,8 +70,9 @@ 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));
 		}
@@ -89,8 +89,8 @@ 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 => {
 				if let Some(data) = try!(self.connection.readable()) {
@@ -104,29 +104,33 @@ impl Handshake {
 					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(())
 	}
 

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::*;
@@ -64,19 +65,25 @@ 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 +111,45 @@ 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)) => {
+	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 does not exist");
+				_ => 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 => {
@@ -153,33 +159,30 @@ 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()
-			},
-			_ => {
+		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()
 	}
 }
-	}
-}
 
 /// Shared host information
 pub struct HostInfo {
@@ -222,26 +225,35 @@ 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 {
+/// 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>,
+}
+
+impl<Message> Host<Message> where Message: Send + Sync + Clone {
 	pub fn new() -> Host<Message> {
 		let config = NetworkConfiguration::new();
 		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 {
+		let mut host = Host::<Message> {
+			info: RwLock::new(HostInfo {
 				keys: KeyPair::create().unwrap(),
 				config: config,
 				nonce: H256::random(),
@@ -249,39 +261,64 @@ impl<Message> Host<Message> where Message: Send {
 				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),
+		};
+		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"),
+		*/
+
+		// self.add_node("enode://a9a921de2ff09a9a4d38b623c67b2d6b477a8e654ae95d874750cbbcb31b33296496a7b4421934e2629269e180823e52c15c2b19fc59592ec51ffe4f2de76ed7@127.0.0.1:30303");
+		// GO bootnodes
+		host.add_node("enode://a979fb575495b8d6db44f750317d0f4622bf4c2aa3365d6af7c284339968eef29b69ad0dce72a4d8db5ebb4968de0e3bec910127f134779fbcb0cb6d3331163c@52.16.188.185:30303"); // IE
+		host.add_node("enode://de471bccee3d042261d52e9bff31458daecc406142b401d4cd848f677479f73104b9fdeb090af9583d3391b7f10cb2ba9e26865dd5fca4fcdc0fb1e3b723c786@54.94.239.50:30303");  // BR
+		host.add_node("enode://1118980bf48b0a3640bdba04e0fe78b1add18e1cd99bf22d53daac1fd9972ad650df52176e7c7d89d1114cfef2bc23a2959aa54998a46afcf7d91809f0855082@52.74.57.123:30303");  // SG
+		// ETH/DEV cpp-ethereum (poc-9.ethdev.com)
+		host.add_node("enode://979b7fa28feeb35a4741660a16076f1943202cb72b6af70d327f053e248bab9ba81760f39d0701ef1d8f89cc1fbd2cacba0710a12cd5314d5e0c9021aa3637f9@5.1.83.226:30303");
+		host
 	}
 
-	fn add_node(&mut self, id: &str) {
+	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
@@ -292,13 +329,14 @@ 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);
 			}
 		}
@@ -312,8 +350,7 @@ 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;
@@ -329,23 +366,26 @@ impl<Message> Host<Message> where Message: Send {
 	}
 
 	#[allow(single_match)]
-	fn connect_peer(&mut self, id: &NodeId, io: &mut IoContext<NetworkIoMessage<Message>>) {
+	#[allow(block_in_if_condition_stmt)]
+	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();
+			let address = {
+				let mut nodes = self.nodes.write().unwrap();
+				let node = nodes.get_mut(id).unwrap();
 				node.last_attempted = Some(::time::now());
-
-			match TcpStream::connect(&node.endpoint.address) {
+				node.endpoint.address
+			};
+			match TcpStream::connect(&address) {
 				Ok(socket) => socket,
 				Err(_) => {
 					warn!("Cannot connect to node");
@@ -354,222 +394,182 @@ impl<Message> Host<Message> where Message: Send {
 			}
 		};
 
-		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| {
+		let nonce = self.info.write().unwrap().next_nonce();
+		if self.connections.write().unwrap().insert_with(|token| {
+			let mut handshake = Handshake::new(token, id, socket, &nonce).expect("Can't create handshake");
+			handshake.start(io, &self.info.read().unwrap(), true).and_then(|_| io.register_stream(token)).unwrap_or_else (|e| {
 				debug!(target: "net", "Handshake create error: {:?}", e);
 			});
-					},
-					_ => {}
-				}
-			},
-			None => { warn!("Max connections reached") }
+			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");
 	}
 
 	#[allow(single_match)]
-	fn connection_writable<'s>(&'s mut self, token: StreamToken, io: &mut IoContext<'s, NetworkIoMessage<Message>>) {
-		let mut kill = false;
+	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| {
+		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;
-				});
-				create_session = h.done();
 						},
-			Some(&mut ConnectionEntry::Session(ref mut s)) => {
-				s.writable(io.event_loop, &self.info).unwrap_or_else(|e| {
+						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| {
+		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;
-				});
-				create_session = h.done();
+					}
+					if h.done() {
+						create_session = true;
+					}
 				},
-			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);
+				ConnectionEntry::Session(ref mut s) => {
+					match s.readable(io, &self.info.read().unwrap()) {
+						Err(e) => {
+							debug!(target: "net", "Handshake read error: {:?}", e);
 							kill = true;
-					SessionData::None
-				}) };
-				match sd {
-					SessionData::Ready => {
-						for (p, _) in &mut self.handlers {
+						},
+						Ok(SessionData::Ready) => {
+							for (p, _) in self.handlers.read().unwrap().iter() {
 								if s.have_capability(p)  {
 									ready_data.push(p);
 								}
 							}
 						},
-					SessionData::Packet {
+						Ok(SessionData::Packet {
 							data,
 							protocol,
 							packet_id,
-					} => {
-						match self.handlers.get_mut(protocol) {
+						}) => {
+							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)),
 							}
 						},
-					SessionData::None => {},
+						Ok(SessionData::None) => {},
 					}
 				}
-			_ => {
-				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;
-		}
-		if create_session {
+		} 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 mut h = self.handlers.get_mut(p).unwrap();
-			h.connected(&mut NetworkContext::new(io, p, Some(token), &mut self.connections, &mut self.timers), &token);
+			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 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..]);
+			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));
 	}
 
-		if let Some(&mut ConnectionEntry::Session(ref mut s)) = self.connections.get_mut(token) {
-			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());
+	fn start_session(&self, token: StreamToken, io: &IoContext<NetworkIoMessage<Message>>) {
+		self.connections.write().unwrap().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");
+					Some(Arc::new(Mutex::new(ConnectionEntry::Session(session))))
 				},
-					Err(e) => {
-						debug!(target: "net", "Session construction error: {:?}", e);
+				_ => { None } // handshake expired
 			}
-				}
-			},
-			_ => 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");
+		}).ok();
 	}
 
-	fn connection_timeout<'s>(&'s mut self, token: StreamToken, io: &mut IoContext<'s, NetworkIoMessage<Message>>) {
+	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 &mut self.handlers {
+		{
+			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;
-			},
+					_ => {},
+				}
+			}
 		}
 		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),
@@ -577,7 +577,7 @@ 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 => {},
@@ -586,66 +586,97 @@ 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 => {},
-			_ => {
-				if let Some(protocol) = self.timers.get_mut(&token).map(|p| *p) {
-					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); }
-					};
-				} // else 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>) {
+	fn message(&self, io: &IoContext<NetworkIoMessage<Message>>, message: &NetworkIoMessage<Message>) {
 		match *message {
 			NetworkIoMessage::AddHandler {
-				ref mut handler,
+				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 });
 				}
 			},
-			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");
 			},
 			NetworkIoMessage::User(ref message) => {
-				for (p, h) in &mut self.handlers {
-					h.message(&mut NetworkContext::new(io, p, None, &mut self.connections, &mut self.timers), &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 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

@@ -8,39 +8,40 @@
 ///
 /// 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]);
+/// 	service.register_protocol(Arc::new(MyHandler), "myproto", &[1u8]);
 ///
 /// 	// Wait for quit condition
 /// 	// ...
@@ -57,36 +58,78 @@ mod error;
 mod node;
 
 /// TODO [arkpar] Please document me
-pub type PeerId = host::PeerId;
+pub use network::host::PeerId;
 /// TODO [arkpar] Please document me
-pub type PacketId = host::PacketId;
+pub use network::host::PacketId;
 /// TODO [arkpar] Please document me
-pub type NetworkContext<'s,'io,  Message> = host::NetworkContext<'s, 'io, Message>;
+pub use network::host::NetworkContext;
 /// TODO [arkpar] Please document me
-pub type NetworkService<Message> = service::NetworkService<Message>;
+pub use network::service::NetworkService;
+/// TODO [arkpar] Please document me
+pub use network::host::NetworkIoMessage;
 /// TODO [arkpar] Please document me
-pub type NetworkIoMessage<Message> = host::NetworkIoMessage<Message>;
 pub use network::host::NetworkIoMessage::User as UserMessage;
 /// TODO [arkpar] Please document me
-pub type NetworkError = error::NetworkError;
+pub use network::error::NetworkError;
 
-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) {}
 }
 
+
+#[test]
+fn test_net_service() {
+
+	use std::sync::Arc;
+	struct MyHandler;
+
+	#[derive(Clone)]
+	struct MyMessage {
+		data: u32
+	}
+
+	impl NetworkProtocolHandler<MyMessage> for MyHandler {
+		fn initialize(&self, io: &NetworkContext<MyMessage>) {
+			io.register_timer(0, 1000).unwrap();
+		}
+
+		fn read(&self, _io: &NetworkContext<MyMessage>, peer: &PeerId, packet_id: u8, data: &[u8]) {
+			println!("Received {} ({} bytes) from {}", packet_id, data.len(), peer);
+		}
+
+		fn connected(&self, _io: &NetworkContext<MyMessage>, peer: &PeerId) {
+			println!("Connected {}", peer);
+		}
+
+		fn disconnected(&self, _io: &NetworkContext<MyMessage>, peer: &PeerId) {
+			println!("Disconnected {}", peer);
+		}
+
+		fn timeout(&self, _io: &NetworkContext<MyMessage>, timer: TimerToken) {
+			println!("Timeout {}", timer);
+		}
+
+		fn message(&self, _io: &NetworkContext<MyMessage>, message: &MyMessage) {
+			println!("Message {}", message.data);
+		}
+	}
+
+	let mut service = NetworkService::<MyMessage>::start().expect("Error creating network service");
+	service.register_protocol(Arc::new(MyHandler), "myproto", &[1u8]).unwrap();
+}

util/src/network/service.rs

@@ -1,23 +1,24 @@
+use std::sync::*;
 use error::*;
 use network::{NetworkProtocolHandler};
 use network::error::{NetworkError};
-use network::host::{Host, NetworkIoMessage, PeerId, PacketId, ProtocolId};
+use network::host::{Host, NetworkIoMessage, ProtocolId};
 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,
 }
 
-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> {
 		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());
+		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,
@@ -25,21 +26,10 @@ impl<Message> NetworkService<Message> where Message: Send + 'static {
 		})
 	}
 
-	/// 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(),
 		}));
@@ -55,7 +45,5 @@ impl<Message> NetworkService<Message> where Message: Send + 'static {
 	pub fn io(&mut self) -> &mut IoService<NetworkIoMessage<Message>> {
 		&mut self.io_service
 	}
-
-
 }
 

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 +127,8 @@ 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)
 	}
 
 	/// Send a protocol packet to peer.