Merge remote-tracking branch 'parity/master' into bft

Conflicts:
	ethcore/src/client/client.rs
	sync/src/api.rs

.gitlab-ci.yml

@@ -266,6 +266,7 @@ test-linux:
   before_script:
     - git submodule update --init --recursive
   script:
+    - export RUST_BACKTRACE=1
     - ./test.sh --verbose
   tags:
     - rust-test

Cargo.lock

@@ -288,6 +288,7 @@ dependencies = [
  "hyper 0.9.4 (git+https://github.com/ethcore/hyper)",
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lru-cache 0.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -317,7 +318,7 @@ dependencies = [
  "ethcore-devtools 1.4.0",
  "ethcore-rpc 1.4.0",
  "ethcore-util 1.4.0",
- "https-fetch 0.1.0",
+ "fetch 0.1.0",
  "hyper 0.9.4 (git+https://github.com/ethcore/hyper)",
  "jsonrpc-core 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "jsonrpc-http-server 6.1.0 (git+https://github.com/ethcore/jsonrpc-http-server.git)",
@@ -466,6 +467,7 @@ dependencies = [
  "ethkey 0.2.0",
  "ethstore 0.1.0",
  "ethsync 1.4.0",
+ "fetch 0.1.0",
  "json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git)",
  "jsonrpc-core 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "jsonrpc-http-server 6.1.0 (git+https://github.com/ethcore/jsonrpc-http-server.git)",
@@ -639,6 +641,16 @@ dependencies = [
  "libc 0.2.15 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "fetch"
+version = "0.1.0"
+dependencies = [
+ "https-fetch 0.1.0",
+ "hyper 0.9.4 (git+https://github.com/ethcore/hyper)",
+ "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "flate2"
 version = "0.2.14"
@@ -690,7 +702,7 @@ version = "0.1.0"
 dependencies = [
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "mio 0.5.1 (git+https://github.com/ethcore/mio?branch=v0.5.x)",
- "rustls 0.1.1 (git+https://github.com/ctz/rustls)",
+ "rustls 0.1.2 (git+https://github.com/ctz/rustls)",
 ]
 
 [[package]]
@@ -852,6 +864,11 @@ name = "libc"
 version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "linked-hash-map"
+version = "0.0.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "linked-hash-map"
 version = "0.3.0"
@@ -862,6 +879,14 @@ name = "log"
 version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "lru-cache"
+version = "0.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "linked-hash-map 0.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "matches"
 version = "0.1.2"
@@ -1345,7 +1370,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "ring"
-version = "0.3.1"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1429,15 +1454,15 @@ dependencies = [
 
 [[package]]
 name = "rustls"
-version = "0.1.1"
+version = "0.1.2"
-source = "git+https://github.com/ctz/rustls#a9c5a79f49337e22ac05bb1ea114240bdbe0fdd2"
+source = "git+https://github.com/ctz/rustls#3d2db624997004b7b18ba4463d6081f37598b2f5"
 dependencies = [
  "base64 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "ring 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ring 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.35 (registry+https://github.com/rust-lang/crates.io-index)",
  "untrusted 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "webpki 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "webpki 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1788,10 +1813,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "webpki"
-version = "0.2.2"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "ring 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ring 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.35 (registry+https://github.com/rust-lang/crates.io-index)",
  "untrusted 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1903,14 +1928,16 @@ dependencies = [
 "checksum itoa 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ae3088ea4baeceb0284ee9eea42f591226e6beaecf65373e41b38d95a1b8e7a1"
 "checksum json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git)" = "<none>"
 "checksum json-tcp-server 0.1.0 (git+https://github.com/ethcore/json-tcp-server)" = "<none>"
-"checksum jsonrpc-core 3.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e913b3c809aab9378889da8b990b4a46b98bd4794c8117946a1cf63c5f87bcde"
+"checksum jsonrpc-core 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "3c5094610b07f28f3edaf3947b732dadb31dbba4941d4d0c1c7a8350208f4414"
 "checksum jsonrpc-http-server 6.1.0 (git+https://github.com/ethcore/jsonrpc-http-server.git)" = "<none>"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum language-tags 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a91d884b6667cd606bb5a69aa0c99ba811a115fc68915e7056ec08a46e93199a"
 "checksum lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "49247ec2a285bb3dcb23cbd9c35193c025e7251bfce77c1d5da97e6362dffe7f"
 "checksum libc 0.2.15 (registry+https://github.com/rust-lang/crates.io-index)" = "23e3757828fa702a20072c37ff47938e9dd331b92fac6e223d26d4b7a55f7ee2"
+"checksum linked-hash-map 0.0.9 (registry+https://github.com/rust-lang/crates.io-index)" = "83f7ff3baae999fdf921cccf54b61842bb3b26868d50d02dff48052ebec8dd79"
 "checksum linked-hash-map 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6d262045c5b87c0861b3f004610afd0e2c851e2908d08b6c870cbb9d5f494ecd"
 "checksum log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "ab83497bf8bf4ed2a74259c1c802351fcd67a65baa86394b6ba73c36f4838054"
+"checksum lru-cache 0.0.7 (registry+https://github.com/rust-lang/crates.io-index)" = "42d50dcb5d9f145df83b1043207e1ac0c37c9c779c4e128ca4655abc3f3cbf8c"
 "checksum matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "15305656809ce5a4805b1ff2946892810992197ce1270ff79baded852187942e"
 "checksum memchr 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "d8b629fb514376c675b98c1421e80b151d3817ac42d7c667717d282761418d20"
 "checksum mime 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a74cc2587bf97c49f3f5bab62860d6abf3902ca73b66b51d9b049fbdcd727bd2"
@@ -1964,7 +1991,7 @@ dependencies = [
 "checksum rayon 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "655df67c314c30fa3055a365eae276eb88aa4f3413a352a1ab32c1320eda41ea"
 "checksum regex 0.1.68 (registry+https://github.com/rust-lang/crates.io-index)" = "b4329b8928a284580a1c63ec9d846b12f6d3472317243ff7077aff11f23f2b29"
 "checksum regex-syntax 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "841591b1e05609a643e3b4d0045fce04f701daba7151ddcd3ad47b080693d5a9"
-"checksum ring 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d059a6a96d3be79042e3f70eb97945912839265f9d8ab45b921abaf266c70dbb"
+"checksum ring 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "0d2f6547bf9640f1d3cc4e771f82374ec8fd237c17eeb3ff5cd5ccbe22377a09"
 "checksum rocksdb 0.4.5 (git+https://github.com/ethcore/rust-rocksdb)" = "<none>"
 "checksum rocksdb-sys 0.3.0 (git+https://github.com/ethcore/rust-rocksdb)" = "<none>"
 "checksum rotor 0.6.3 (git+https://github.com/ethcore/rotor)" = "<none>"
@@ -1972,7 +1999,7 @@ dependencies = [
 "checksum rust-crypto 0.2.36 (registry+https://github.com/rust-lang/crates.io-index)" = "f76d05d3993fd5f4af9434e8e436db163a12a9d40e1a58a726f27a01dfd12a2a"
 "checksum rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)" = "6159e4e6e559c81bd706afe9c8fd68f547d3e851ce12e76b1de7914bab61691b"
 "checksum rustc_version 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "c5f5376ea5e30ce23c03eb77cbe4962b988deead10910c372b226388b594c084"
-"checksum rustls 0.1.1 (git+https://github.com/ctz/rustls)" = "<none>"
+"checksum rustls 0.1.2 (git+https://github.com/ctz/rustls)" = "<none>"
 "checksum semver 0.1.20 (registry+https://github.com/rust-lang/crates.io-index)" = "d4f410fedcf71af0345d7607d246e7ad15faaadd49d240ee3b24e5dc21a820ac"
 "checksum semver 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2d5b7638a1f03815d94e88cb3b3c08e87f0db4d683ef499d1836aaf70a45623f"
 "checksum serde 0.8.4 (registry+https://github.com/rust-lang/crates.io-index)" = "b1dfda9ebb31d29fa8b94d7eb3031a86a8dcec065f0fe268a30f98867bf45775"
@@ -2017,7 +2044,7 @@ dependencies = [
 "checksum vecio 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0795a11576d29ae80525a3fda315bf7b534f8feb9d34101e5fe63fb95bb2fd24"
 "checksum vergen 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "56b639f935488eb40f06d17c3e3bcc3054f6f75d264e187b1107c8d1cba8d31c"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
-"checksum webpki 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "5dc10a815fabbb0c3145c1153240528f3a8703a47e26e8dbb4a5d4f6386200ad"
+"checksum webpki 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "813503a5985585e0812d430cd1328ee322f47f66629c8ed4ecab939cf9e92f91"
 "checksum winapi 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "4dfaaa8fbdaa618fa6914b59b2769d690dd7521920a18d84b42d254678dd5fd4"
 "checksum winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"
 "checksum ws 0.5.2 (git+https://github.com/ethcore/ws-rs.git?branch=mio-upstream-stable)" = "<none>"

dapps/Cargo.toml

@@ -26,7 +26,7 @@ linked-hash-map = "0.3"
 ethcore-devtools = { path = "../devtools" }
 ethcore-rpc = { path = "../rpc" }
 ethcore-util = { path = "../util" }
-https-fetch = { path = "../util/https-fetch" }
+fetch = { path = "../util/fetch" }
 parity-dapps = { git = "https://github.com/ethcore/parity-ui.git", version = "1.4" }
 # List of apps
 parity-dapps-status = { git = "https://github.com/ethcore/parity-ui.git", version = "1.4" }

dapps/src/handlers/client/mod.rs

@@ -1,113 +0,0 @@
-// Copyright 2015, 2016 Ethcore (UK) Ltd.
-// This file is part of Parity.
-
-// Parity is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-
-// Parity is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU General Public License for more details.
-
-// You should have received a copy of the GNU General Public License
-// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
-
-//! Hyper Client Handlers
-
-pub mod fetch_file;
-
-use std::env;
-use std::sync::{mpsc, Arc};
-use std::sync::atomic::AtomicBool;
-use std::path::PathBuf;
-
-use hyper;
-use https_fetch as https;
-
-use random_filename;
-use self::fetch_file::{Fetch, Error as HttpFetchError};
-
-pub type FetchResult = Result<PathBuf, FetchError>;
-
-#[derive(Debug)]
-pub enum FetchError {
-	InvalidUrl,
-	Http(HttpFetchError),
-	Https(https::FetchError),
-	Other(String),
-}
-
-impl From<HttpFetchError> for FetchError {
-	fn from(e: HttpFetchError) -> Self {
-		FetchError::Http(e)
-	}
-}
-
-pub struct Client {
-	http_client: hyper::Client<Fetch>,
-	https_client: https::Client,
-}
-
-impl Client {
-	pub fn new() -> Self {
-		Client {
-			http_client: hyper::Client::new().expect("Unable to initialize http client."),
-			https_client: https::Client::new().expect("Unable to initialize https client."),
-		}
-	}
-
-	pub fn close(self) {
-		self.http_client.close();
-		self.https_client.close();
-	}
-
-	pub fn request(&mut self, url: &str, abort: Arc<AtomicBool>, on_done: Box<Fn() + Send>) -> Result<mpsc::Receiver<FetchResult>, FetchError> {
-		let is_https = url.starts_with("https://");
-		let url = try!(url.parse().map_err(|_| FetchError::InvalidUrl));
-		trace!(target: "dapps", "Fetching from: {:?}", url);
-		if is_https {
-			let url = try!(Self::convert_url(url));
-
-			let (tx, rx) = mpsc::channel();
-			let temp_path = Self::temp_path();
-			let res = self.https_client.fetch_to_file(url, temp_path.clone(), abort, move |result| {
-				let res = tx.send(
-					result.map(|_| temp_path).map_err(FetchError::Https)
-				);
-				if let Err(_) = res {
-					warn!("Fetch finished, but no one was listening");
-				}
-				on_done();
-			});
-
-			match res {
-				Ok(_) => Ok(rx),
-				Err(e) => Err(FetchError::Other(format!("{:?}", e))),
-			}
-		} else {
-			let (tx, rx) = mpsc::channel();
-			let res = self.http_client.request(url, Fetch::new(tx, abort, on_done));
-
-			match res {
-				Ok(_) => Ok(rx),
-				Err(e) => Err(FetchError::Other(format!("{:?}", e))),
-			}
-		}
-	}
-
-	fn convert_url(url: hyper::Url) -> Result<https::Url, FetchError> {
-		let host = format!("{}", try!(url.host().ok_or(FetchError::InvalidUrl)));
-		let port = try!(url.port_or_known_default().ok_or(FetchError::InvalidUrl));
-		https::Url::new(&host, port, url.path()).map_err(|_| FetchError::InvalidUrl)
-	}
-
-	fn temp_path() -> PathBuf {
-		let mut dir = env::temp_dir();
-		dir.push(random_filename());
-		dir
-	}
-}
-
-

dapps/src/handlers/fetch.rs

@@ -22,13 +22,13 @@ use std::sync::{mpsc, Arc};
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::time::{Instant, Duration};
 use util::Mutex;
+use fetch::{Client, Fetch, FetchResult};
 
 use hyper::{server, Decoder, Encoder, Next, Method, Control};
 use hyper::net::HttpStream;
 use hyper::status::StatusCode;
 
 use handlers::{ContentHandler, Redirection};
-use handlers::client::{Client, FetchResult};
 use apps::redirection_address;
 use page::LocalPageEndpoint;
 
@@ -159,7 +159,7 @@ impl<H: ContentValidator> ContentFetcherHandler<H> {
 		handler: H) -> (Self, Arc<FetchControl>) {
 
 		let fetch_control = Arc::new(FetchControl::default());
-		let client = Client::new();
+		let client = Client::default();
 		let handler = ContentFetcherHandler {
 			fetch_control: fetch_control.clone(),
 			control: Some(control),

dapps/src/handlers/mod.rs

@@ -21,7 +21,6 @@ mod echo;
 mod content;
 mod redirect;
 mod fetch;
-pub mod client;
 
 pub use self::auth::AuthRequiredHandler;
 pub use self::echo::EchoHandler;

dapps/src/lib.rs

@@ -58,10 +58,10 @@ extern crate jsonrpc_http_server;
 extern crate mime_guess;
 extern crate rustc_serialize;
 extern crate parity_dapps;
-extern crate https_fetch;
 extern crate ethcore_rpc;
 extern crate ethcore_util as util;
 extern crate linked_hash_map;
+extern crate fetch;
 #[cfg(test)]
 extern crate ethcore_devtools as devtools;
 

ethash/src/compute.rs

@@ -202,6 +202,9 @@ impl SeedHashCompute {
 	}
 }
 
+pub fn slow_get_seedhash(block_number: u64) -> H256 {
+	SeedHashCompute::resume_compute_seedhash([0u8; 32], 0, block_number / ETHASH_EPOCH_LENGTH)
+}
 
 #[inline]
 fn fnv_hash(x: u32, y: u32) -> u32 {

ethash/src/lib.rs

@@ -26,7 +26,7 @@ mod compute;
 
 use std::mem;
 use compute::Light;
-pub use compute::{ETHASH_EPOCH_LENGTH, H256, ProofOfWork, SeedHashCompute, quick_get_difficulty};
+pub use compute::{ETHASH_EPOCH_LENGTH, H256, ProofOfWork, SeedHashCompute, quick_get_difficulty, slow_get_seedhash};
 
 use std::sync::Arc;
 use parking_lot::Mutex;

ethcore/Cargo.toml

@@ -37,6 +37,7 @@ ethkey = { path = "../ethkey" }
 ethcore-ipc-nano = { path = "../ipc/nano" }
 rlp = { path = "../util/rlp" }
 rand = "0.3"
+lru-cache = "0.0.7"
 
 [dependencies.hyper]
 git = "https://github.com/ethcore/hyper"

ethcore/res/ethereum/expanse.json

@@ -0,0 +1,69 @@
+{
+	"name": "Expanse",
+	"forkName": "expanse",
+	"engine": {
+		"Ethash": {
+			"params": {
+				"gasLimitBoundDivisor": "0x0400",
+				"minimumDifficulty": "0x020000",
+				"difficultyBoundDivisor": "0x0800",
+				"difficultyIncrementDivisor": "60",
+				"durationLimit": "0x3C",
+				"blockReward": "0x6f05b59d3b200000",
+				"registrar" : "0x6c221ca53705f3497ec90ca7b84c59ae7382fc21",
+				"frontierCompatibilityModeLimit": "0x30d40",
+				"difficultyHardforkTransition": "0x59d9",
+				"difficultyHardforkBoundDivisor": "0x0200",
+				"bombDefuseTransition": "0x30d40"
+			}
+		}
+	},
+	"params": {
+		"accountStartNonce": "0x00",
+		"maximumExtraDataSize": "0x20",
+		"minGasLimit": "0x1388",
+		"networkID": "0x1",
+		"subprotocolName": "exp"
+	},
+	"genesis": {
+		"seal": {
+			"ethereum": {
+				"nonce": "0x214652414e4b4f21",
+				"mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
+			}
+		},
+		"difficulty": "0x40000000",
+		"author": "0x93decab0cd745598860f782ac1e8f046cb99e898",
+		"timestamp": "0x00",
+		"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
+		"extraData": "0x4672616e6b6f497346726565646f6d",
+		"gasLimit": "0x1388"
+	},
+	"nodes": [
+		"enode://7f335a047654f3e70d6f91312a7cf89c39704011f1a584e2698250db3d63817e74b88e26b7854111e16b2c9d0c7173c05419aeee2d0321850227b126d8b1be3f@46.101.156.249:42786",
+		"enode://df872f81e25f72356152b44cab662caf1f2e57c3a156ecd20e9ac9246272af68a2031b4239a0bc831f2c6ab34733a041464d46b3ea36dce88d6c11714446e06b@178.62.208.109:42786",
+		"enode://96d3919b903e7f5ad59ac2f73c43be9172d9d27e2771355db03fd194732b795829a31fe2ea6de109d0804786c39a807e155f065b4b94c6fce167becd0ac02383@45.55.22.34:42786",
+		"enode://5f6c625bf287e3c08aad568de42d868781e961cbda805c8397cfb7be97e229419bef9a5a25a75f97632787106bba8a7caf9060fab3887ad2cfbeb182ab0f433f@46.101.182.53:42786",
+		"enode://d33a8d4c2c38a08971ed975b750f21d54c927c0bf7415931e214465a8d01651ecffe4401e1db913f398383381413c78105656d665d83f385244ab302d6138414@128.199.183.48:42786",
+		"enode://df872f81e25f72356152b44cab662caf1f2e57c3a156ecd20e9ac9246272af68a2031b4239a0bc831f2c6ab34733a041464d46b3ea36dce88d6c11714446e06b@178.62.208.109:42786",
+		"enode://f6f0d6b9b7d02ec9e8e4a16e38675f3621ea5e69860c739a65c1597ca28aefb3cec7a6d84e471ac927d42a1b64c1cbdefad75e7ce8872d57548ddcece20afdd1@159.203.64.95:42786"
+	],
+	"accounts": {
+		"0000000000000000000000000000000000000001": { "builtin": { "name": "ecrecover", "pricing": { "linear": { "base": 3000, "word": 0 } } } },
+		"0000000000000000000000000000000000000002": { "builtin": { "name": "sha256", "pricing": { "linear": { "base": 60, "word": 12 } } } },
+		"0000000000000000000000000000000000000003": { "builtin": { "name": "ripemd160", "pricing": { "linear": { "base": 600, "word": 120 } } } },
+		"0000000000000000000000000000000000000004": { "builtin": { "name": "identity", "pricing": { "linear": { "base": 15, "word": 3 } } } },
+		"bb94f0ceb32257275b2a7a9c094c13e469b4563e": {
+			"balance": "10000000000000000000000000"
+		},
+		"15656715068ab0dbdf0ab00748a8a19e40f28192": {
+			"balance": "1000000000000000000000000"
+		},
+		"c075fa11f85bda3aaba67106226aaf086ac16f4e": {
+			"balance": "100000000000000000000000"
+		},
+		"93decab0cd745598860f782ac1e8f046cb99e898": {
+			"balance": "10000000000000000000000"
+		}
+	}
+}

ethcore/res/ethereum/frontier.json

@@ -157,6 +157,9 @@
 		"stateRoot": "0xd7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544"
 	},
 	"nodes": [
+		"enode://cd6611461840543d5b9c56fbf088736154c699c43973b3a1a32390cf27106f87e58a818a606ccb05f3866de95a4fe860786fea71bf891ea95f234480d3022aa3@136.243.154.245:30303",
+		"enode://bcc7240543fe2cf86f5e9093d05753dd83343f8fda7bf0e833f65985c73afccf8f981301e13ef49c4804491eab043647374df1c4adf85766af88a624ecc3330e@136.243.154.244:30303",
+		"enode://ed4227681ca8c70beb2277b9e870353a9693f12e7c548c35df6bca6a956934d6f659999c2decb31f75ce217822eefca149ace914f1cbe461ed5a2ebaf9501455@88.212.206.70:30303",
 		"enode://a979fb575495b8d6db44f750317d0f4622bf4c2aa3365d6af7c284339968eef29b69ad0dce72a4d8db5ebb4968de0e3bec910127f134779fbcb0cb6d3331163c@52.16.188.185:30303",
 		"enode://de471bccee3d042261d52e9bff31458daecc406142b401d4cd848f677479f73104b9fdeb090af9583d3391b7f10cb2ba9e26865dd5fca4fcdc0fb1e3b723c786@54.94.239.50:30303",
 		"enode://1118980bf48b0a3640bdba04e0fe78b1add18e1cd99bf22d53daac1fd9972ad650df52176e7c7d89d1114cfef2bc23a2959aa54998a46afcf7d91809f0855082@52.74.57.123:30303",

ethcore/src/block.rs

@@ -19,6 +19,7 @@
 use common::*;
 use engines::Engine;
 use state::*;
+use state_db::StateDB;
 use verification::PreverifiedBlock;
 use trace::FlatTrace;
 use factory::Factories;
@@ -69,7 +70,7 @@ impl Decodable for Block {
 	}
 }
 
-/// Internal type for a block's common elements.
+/// An internal type for a block's common elements.
 #[derive(Clone)]
 pub struct ExecutedBlock {
 	base: Block,
@@ -179,7 +180,7 @@ pub trait IsBlock {
 /// Trait for a object that has a state database.
 pub trait Drain {
 	/// Drop this object and return the underlieing database.
-	fn drain(self) -> Box<JournalDB>;
+	fn drain(self) -> StateDB;
 }
 
 impl IsBlock for ExecutedBlock {
@@ -205,6 +206,7 @@ pub struct ClosedBlock {
 	block: ExecutedBlock,
 	uncle_bytes: Bytes,
 	last_hashes: Arc<LastHashes>,
+	unclosed_state: State,
 }
 
 /// Just like `ClosedBlock` except that we can't reopen it and it's faster.
@@ -231,7 +233,7 @@ impl<'x> OpenBlock<'x> {
 		engine: &'x Engine,
 		factories: Factories,
 		tracing: bool,
-		db: Box<JournalDB>,
+		db: StateDB,
 		parent: &Header,
 		last_hashes: Arc<LastHashes>,
 		author: Address,
@@ -346,8 +348,7 @@ impl<'x> OpenBlock<'x> {
 	pub fn close(self) -> ClosedBlock {
 		let mut s = self;
 
-		// take a snapshot so the engine's changes can be rolled back.
+		let unclosed_state = s.block.state.clone();
-		s.block.state.snapshot();
 
 		s.engine.on_close_block(&mut s.block);
 		s.block.base.header.set_transactions_root(ordered_trie_root(s.block.base.transactions.iter().map(|e| e.rlp_bytes().to_vec())));
@@ -362,6 +363,7 @@ impl<'x> OpenBlock<'x> {
 			block: s.block,
 			uncle_bytes: uncle_bytes,
 			last_hashes: s.last_hashes,
+			unclosed_state: unclosed_state,
 		}
 	}
 
@@ -369,9 +371,6 @@ impl<'x> OpenBlock<'x> {
 	pub fn close_and_lock(self) -> LockedBlock {
 		let mut s = self;
 
-		// take a snapshot so the engine's changes can be rolled back.
-		s.block.state.snapshot();
-
 		s.engine.on_close_block(&mut s.block);
 		if s.block.base.header.transactions_root().is_zero() || s.block.base.header.transactions_root() == &SHA3_NULL_RLP {
 			s.block.base.header.set_transactions_root(ordered_trie_root(s.block.base.transactions.iter().map(|e| e.rlp_bytes().to_vec())));
@@ -388,11 +387,10 @@ impl<'x> OpenBlock<'x> {
 		s.block.base.header.set_log_bloom(s.block.receipts.iter().fold(LogBloom::zero(), |mut b, r| {b = &b | &r.log_bloom; b})); //TODO: use |= operator
 		s.block.base.header.set_gas_used(s.block.receipts.last().map_or(U256::zero(), |r| r.gas_used));
 
-		ClosedBlock {
+		LockedBlock {
 			block: s.block,
 			uncle_bytes: uncle_bytes,
-			last_hashes: s.last_hashes,
+		}
-		}.lock()
 	}
 }
 
@@ -413,17 +411,7 @@ impl ClosedBlock {
 	pub fn hash(&self) -> H256 { self.header().rlp_sha3(Seal::Without) }
 
 	/// Turn this into a `LockedBlock`, unable to be reopened again.
-	pub fn lock(mut self) -> LockedBlock {
+	pub fn lock(self) -> LockedBlock {
-		// finalize the changes made by the engine.
-		self.block.state.clear_snapshot();
-		if let Err(e) = self.block.state.commit() {
-			warn!("Error committing closed block's state: {:?}", e);
-		}
-
-		// set the state root here, after commit recalculates with the block
-		// rewards.
-		self.block.base.header.set_state_root(self.block.state.root().clone());
-
 		LockedBlock {
 			block: self.block,
 			uncle_bytes: self.uncle_bytes,
@@ -431,12 +419,12 @@ impl ClosedBlock {
 	}
 
 	/// Given an engine reference, reopen the `ClosedBlock` into an `OpenBlock`.
-	pub fn reopen(mut self, engine: &Engine) -> OpenBlock {
+	pub fn reopen(self, engine: &Engine) -> OpenBlock {
 		// revert rewards (i.e. set state back at last transaction's state).
-		self.block.state.revert_snapshot();
+		let mut block = self.block;
-
+		block.state = self.unclosed_state;
 		OpenBlock {
-			block: self.block,
+			block: block,
 			engine: engine,
 			last_hashes: self.last_hashes,
 		}
@@ -462,11 +450,11 @@ impl LockedBlock {
 	/// Provide a valid seal in order to turn this into a `SealedBlock`.
 	/// This does check the validity of `seal` with the engine.
 	/// Returns the `ClosedBlock` back again if the seal is no good.
-	pub fn try_seal(self, engine: &Engine, seal: Vec<Bytes>) -> Result<SealedBlock, LockedBlock> {
+	pub fn try_seal(self, engine: &Engine, seal: Vec<Bytes>) -> Result<SealedBlock, (Error, LockedBlock)> {
 		let mut s = self;
 		s.block.base.header.set_seal(seal);
 		match engine.verify_block_seal(&s.block.base.header) {
-			Err(_) => Err(s),
+			Err(e) => Err((e, s)),
 			_ => Ok(SealedBlock { block: s.block, uncle_bytes: s.uncle_bytes }),
 		}
 	}
@@ -474,7 +462,9 @@ impl LockedBlock {
 
 impl Drain for LockedBlock {
 	/// Drop this object and return the underlieing database.
-	fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
+	fn drain(self) -> StateDB {
+		self.block.state.drop().1
+	}
 }
 
 impl SealedBlock {
@@ -490,7 +480,9 @@ impl SealedBlock {
 
 impl Drain for SealedBlock {
 	/// Drop this object and return the underlieing database.
-	fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
+	fn drain(self) -> StateDB {
+		self.block.state.drop().1
+	}
 }
 
 impl IsBlock for SealedBlock {
@@ -505,7 +497,7 @@ pub fn enact(
 	uncles: &[Header],
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	factories: Factories,
@@ -537,7 +529,7 @@ pub fn enact_bytes(
 	block_bytes: &[u8],
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	factories: Factories,
@@ -553,7 +545,7 @@ pub fn enact_verified(
 	block: &PreverifiedBlock,
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	factories: Factories,
@@ -568,7 +560,7 @@ pub fn enact_and_seal(
 	block_bytes: &[u8],
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	factories: Factories,
@@ -588,9 +580,9 @@ mod tests {
 		use spec::*;
 		let spec = Spec::new_test();
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let b = OpenBlock::new(&*spec.engine, Default::default(), false, db, &genesis_header, last_hashes, Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
 		let b = b.close_and_lock();
@@ -604,25 +596,25 @@ mod tests {
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
 
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let b = OpenBlock::new(engine, Default::default(), false, db, &genesis_header, last_hashes.clone(), Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap()
 			.close_and_lock().seal(engine, vec![]).unwrap();
 		let orig_bytes = b.rlp_bytes();
 		let orig_db = b.drain();
 
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let e = enact_and_seal(&orig_bytes, engine, false, db, &genesis_header, last_hashes, Default::default()).unwrap();
 
 		assert_eq!(e.rlp_bytes(), orig_bytes);
 
 		let db = e.drain();
-		assert_eq!(orig_db.keys(), db.keys());
+		assert_eq!(orig_db.journal_db().keys(), db.journal_db().keys());
-		assert!(orig_db.keys().iter().filter(|k| orig_db.get(k.0) != db.get(k.0)).next() == None);
+		assert!(orig_db.journal_db().keys().iter().filter(|k| orig_db.journal_db().get(k.0) != db.journal_db().get(k.0)).next() == None);
 	}
 
 	#[test]
@@ -632,9 +624,9 @@ mod tests {
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
 
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let mut open_block = OpenBlock::new(engine, Default::default(), false, db, &genesis_header, last_hashes.clone(), Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
 		let mut uncle1_header = Header::new();
@@ -648,9 +640,9 @@ mod tests {
 		let orig_bytes = b.rlp_bytes();
 		let orig_db = b.drain();
 
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let e = enact_and_seal(&orig_bytes, engine, false, db, &genesis_header, last_hashes, Default::default()).unwrap();
 
 		let bytes = e.rlp_bytes();
@@ -659,7 +651,7 @@ mod tests {
 		assert_eq!(uncles[1].extra_data(), b"uncle2");
 
 		let db = e.drain();
-		assert_eq!(orig_db.keys(), db.keys());
+		assert_eq!(orig_db.journal_db().keys(), db.journal_db().keys());
-		assert!(orig_db.keys().iter().filter(|k| orig_db.get(k.0) != db.get(k.0)).next() == None);
+		assert!(orig_db.journal_db().keys().iter().filter(|k| orig_db.journal_db().get(k.0) != db.journal_db().get(k.0)).next() == None);
 	}
 }

ethcore/src/blockchain/blockchain.rs

@@ -181,7 +181,7 @@ pub struct BlockChain {
 
 	pending_best_block: RwLock<Option<BestBlock>>,
 	pending_block_hashes: RwLock<HashMap<BlockNumber, H256>>,
-	pending_transaction_addresses: RwLock<HashMap<H256, TransactionAddress>>,
+	pending_transaction_addresses: RwLock<HashMap<H256, Option<TransactionAddress>>>,
 }
 
 impl BlockProvider for BlockChain {
@@ -331,11 +331,12 @@ impl BlockProvider for BlockChain {
 			.filter_map(|number| self.block_hash(number).map(|hash| (number, hash)))
 			.filter_map(|(number, hash)| self.block_receipts(&hash).map(|r| (number, hash, r.receipts)))
 			.filter_map(|(number, hash, receipts)| self.block_body(&hash).map(|ref b| (number, hash, receipts, BodyView::new(b).transaction_hashes())))
-			.flat_map(|(number, hash, mut receipts, hashes)| {
+			.flat_map(|(number, hash, mut receipts, mut hashes)| {
 				assert_eq!(receipts.len(), hashes.len());
 				log_index = receipts.iter().fold(0, |sum, receipt| sum + receipt.logs.len());
 
 				let receipts_len = receipts.len();
+				hashes.reverse();
 				receipts.reverse();
 				receipts.into_iter()
 					.map(|receipt| receipt.logs)
@@ -680,8 +681,8 @@ impl BlockChain {
 				block_hashes: self.prepare_block_hashes_update(bytes, &info),
 				block_details: self.prepare_block_details_update(bytes, &info),
 				block_receipts: self.prepare_block_receipts_update(receipts, &info),
-				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				blocks_blooms: self.prepare_block_blooms_update(bytes, &info),
+				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				info: info,
 				block: bytes
 			}, is_best);
@@ -714,8 +715,8 @@ impl BlockChain {
 				block_hashes: self.prepare_block_hashes_update(bytes, &info),
 				block_details: update,
 				block_receipts: self.prepare_block_receipts_update(receipts, &info),
-				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				blocks_blooms: self.prepare_block_blooms_update(bytes, &info),
+				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				info: info,
 				block: bytes,
 			}, is_best);
@@ -783,8 +784,8 @@ impl BlockChain {
 			block_hashes: self.prepare_block_hashes_update(bytes, &info),
 			block_details: self.prepare_block_details_update(bytes, &info),
 			block_receipts: self.prepare_block_receipts_update(receipts, &info),
-			transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 			blocks_blooms: self.prepare_block_blooms_update(bytes, &info),
+			transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 			info: info.clone(),
 			block: bytes,
 		}, true);
@@ -877,7 +878,7 @@ impl BlockChain {
 			let mut write_txs = self.pending_transaction_addresses.write();
 
 			batch.extend_with_cache(db::COL_EXTRA, &mut *write_hashes, update.block_hashes, CacheUpdatePolicy::Overwrite);
-			batch.extend_with_cache(db::COL_EXTRA, &mut *write_txs, update.transactions_addresses, CacheUpdatePolicy::Overwrite);
+			batch.extend_with_option_cache(db::COL_EXTRA, &mut *write_txs, update.transactions_addresses, CacheUpdatePolicy::Overwrite);
 		}
 	}
 
@@ -895,18 +896,25 @@ impl BlockChain {
 			*best_block = block;
 		}
 
+		let pending_txs = mem::replace(&mut *pending_write_txs, HashMap::new());
+		let (retracted_txs, enacted_txs) = pending_txs.into_iter().partition::<HashMap<_, _>, _>(|&(_, ref value)| value.is_none());
+
 		let pending_hashes_keys: Vec<_> = pending_write_hashes.keys().cloned().collect();
-		let pending_txs_keys: Vec<_> = pending_write_txs.keys().cloned().collect();
+		let enacted_txs_keys: Vec<_> = enacted_txs.keys().cloned().collect();
 
 		write_hashes.extend(mem::replace(&mut *pending_write_hashes, HashMap::new()));
-		write_txs.extend(mem::replace(&mut *pending_write_txs, HashMap::new()));
+		write_txs.extend(enacted_txs.into_iter().map(|(k, v)| (k, v.expect("Transactions were partitioned; qed"))));
+
+		for hash in retracted_txs.keys() {
+			write_txs.remove(hash);
+		}
 
 		let mut cache_man = self.cache_man.lock();
 		for n in pending_hashes_keys {
 			cache_man.note_used(CacheID::BlockHashes(n));
 		}
 
-		for hash in pending_txs_keys {
+		for hash in enacted_txs_keys {
 			cache_man.note_used(CacheID::TransactionAddresses(hash));
 		}
 	}
@@ -1008,7 +1016,7 @@ impl BlockChain {
 	}
 
 	/// This function returns modified transaction addresses.
-	fn prepare_transaction_addresses_update(&self, block_bytes: &[u8], info: &BlockInfo) -> HashMap<H256, TransactionAddress> {
+	fn prepare_transaction_addresses_update(&self, block_bytes: &[u8], info: &BlockInfo) -> HashMap<H256, Option<TransactionAddress>> {
 		let block = BlockView::new(block_bytes);
 		let transaction_hashes = block.transaction_hashes();
 
@@ -1017,10 +1025,10 @@ impl BlockChain {
 				transaction_hashes.into_iter()
 					.enumerate()
 					.map(|(i ,tx_hash)| {
-						(tx_hash, TransactionAddress {
+						(tx_hash, Some(TransactionAddress {
 							block_hash: info.hash.clone(),
 							index: i
-						})
+						}))
 					})
 					.collect()
 			},
@@ -1031,23 +1039,30 @@ impl BlockChain {
 						let hashes = BodyView::new(&bytes).transaction_hashes();
 						hashes.into_iter()
 							.enumerate()
-							.map(|(i, tx_hash)| (tx_hash, TransactionAddress {
+							.map(|(i, tx_hash)| (tx_hash, Some(TransactionAddress {
 								block_hash: hash.clone(),
 								index: i,
-							}))
+							})))
-							.collect::<HashMap<H256, TransactionAddress>>()
+							.collect::<HashMap<H256, Option<TransactionAddress>>>()
 					});
 
 				let current_addresses = transaction_hashes.into_iter()
 					.enumerate()
 					.map(|(i ,tx_hash)| {
-						(tx_hash, TransactionAddress {
+						(tx_hash, Some(TransactionAddress {
 							block_hash: info.hash.clone(),
 							index: i
-						})
+						}))
 					});
 
-				addresses.chain(current_addresses).collect()
+				let retracted = data.retracted.iter().flat_map(|hash| {
+					let bytes = self.block_body(hash).expect("Retracted block must be in database.");
+					let hashes = BodyView::new(&bytes).transaction_hashes();
+					hashes.into_iter().map(|hash| (hash, None)).collect::<HashMap<H256, Option<TransactionAddress>>>()
+				});
+
+				// The order here is important! Don't remove transaction if it was part of enacted blocks as well.
+				retracted.chain(addresses).chain(current_addresses).collect()
 			},
 			BlockLocation::Branch => HashMap::new(),
 		}
@@ -1345,6 +1360,70 @@ mod tests {
 		// TODO: insert block that already includes one of them as an uncle to check it's not allowed.
 	}
 
+	#[test]
+	fn test_fork_transaction_addresses() {
+		let mut canon_chain = ChainGenerator::default();
+		let mut finalizer = BlockFinalizer::default();
+		let genesis = canon_chain.generate(&mut finalizer).unwrap();
+		let mut fork_chain = canon_chain.fork(1);
+		let mut fork_finalizer = finalizer.fork();
+
+		let t1 = Transaction {
+			nonce: 0.into(),
+			gas_price: 0.into(),
+			gas: 100_000.into(),
+			action: Action::Create,
+			value: 100.into(),
+			data: "601080600c6000396000f3006000355415600957005b60203560003555".from_hex().unwrap(),
+		}.sign(&"".sha3());
+
+
+		let b1a = canon_chain
+			.with_transaction(t1.clone())
+			.generate(&mut finalizer).unwrap();
+
+		// Empty block
+		let b1b = fork_chain
+			.generate(&mut fork_finalizer).unwrap();
+
+		let b2 = fork_chain
+			.generate(&mut fork_finalizer).unwrap();
+
+		let b1a_hash = BlockView::new(&b1a).header_view().sha3();
+		let b2_hash = BlockView::new(&b2).header_view().sha3();
+
+		let t1_hash = t1.hash();
+
+		let temp = RandomTempPath::new();
+		let db = new_db(temp.as_str());
+		let bc = BlockChain::new(Config::default(), &genesis, db.clone());
+
+		let mut batch = db.transaction();
+		let _ = bc.insert_block(&mut batch, &b1a, vec![]);
+		bc.commit();
+		let _ = bc.insert_block(&mut batch, &b1b, vec![]);
+		bc.commit();
+		db.write(batch).unwrap();
+
+		assert_eq!(bc.best_block_hash(), b1a_hash);
+		assert_eq!(bc.transaction_address(&t1_hash), Some(TransactionAddress {
+			block_hash: b1a_hash.clone(),
+			index: 0,
+		}));
+
+		// now let's make forked chain the canon chain
+		let mut batch = db.transaction();
+		let _ = bc.insert_block(&mut batch, &b2, vec![]);
+		bc.commit();
+		db.write(batch).unwrap();
+
+		// Transaction should be retracted
+		assert_eq!(bc.best_block_hash(), b2_hash);
+		assert_eq!(bc.transaction_address(&t1_hash), None);
+	}
+
+
+
 	#[test]
 	fn test_overwriting_transaction_addresses() {
 		let mut canon_chain = ChainGenerator::default();
@@ -1415,14 +1494,14 @@ mod tests {
 		db.write(batch).unwrap();
 
 		assert_eq!(bc.best_block_hash(), b1a_hash);
-		assert_eq!(bc.transaction_address(&t1_hash).unwrap(), TransactionAddress {
+		assert_eq!(bc.transaction_address(&t1_hash), Some(TransactionAddress {
 			block_hash: b1a_hash.clone(),
 			index: 0,
-		});
+		}));
-		assert_eq!(bc.transaction_address(&t2_hash).unwrap(), TransactionAddress {
+		assert_eq!(bc.transaction_address(&t2_hash), Some(TransactionAddress {
 			block_hash: b1a_hash.clone(),
 			index: 1,
-		});
+		}));
 
 		// now let's make forked chain the canon chain
 		let mut batch = db.transaction();
@@ -1431,18 +1510,18 @@ mod tests {
 		db.write(batch).unwrap();
 
 		assert_eq!(bc.best_block_hash(), b2_hash);
-		assert_eq!(bc.transaction_address(&t1_hash).unwrap(), TransactionAddress {
+		assert_eq!(bc.transaction_address(&t1_hash), Some(TransactionAddress {
 			block_hash: b1b_hash.clone(),
 			index: 1,
-		});
+		}));
-		assert_eq!(bc.transaction_address(&t2_hash).unwrap(), TransactionAddress {
+		assert_eq!(bc.transaction_address(&t2_hash), Some(TransactionAddress {
 			block_hash: b1b_hash.clone(),
 			index: 0,
-		});
+		}));
-		assert_eq!(bc.transaction_address(&t3_hash).unwrap(), TransactionAddress {
+		assert_eq!(bc.transaction_address(&t3_hash), Some(TransactionAddress {
 			block_hash: b2_hash.clone(),
 			index: 0,
-		});
+		}));
 	}
 
 	#[test]
@@ -1682,7 +1761,7 @@ mod tests {
 			gas_price: 0.into(),
 			gas: 100_000.into(),
 			action: Action::Create,
-			value: 100.into(),
+			value: 101.into(),
 			data: "601080600c6000396000f3006000355415600957005b60203560003555".from_hex().unwrap(),
 		}.sign(&"".sha3());
 		let t2 = Transaction {
@@ -1690,7 +1769,7 @@ mod tests {
 			gas_price: 0.into(),
 			gas: 100_000.into(),
 			action: Action::Create,
-			value: 100.into(),
+			value: 102.into(),
 			data: "601080600c6000396000f3006000355415600957005b60203560003555".from_hex().unwrap(),
 		}.sign(&"".sha3());
 		let t3 = Transaction {
@@ -1698,7 +1777,7 @@ mod tests {
 			gas_price: 0.into(),
 			gas: 100_000.into(),
 			action: Action::Create,
-			value: 100.into(),
+			value: 103.into(),
 			data: "601080600c6000396000f3006000355415600957005b60203560003555".from_hex().unwrap(),
 		}.sign(&"".sha3());
 		let tx_hash1 = t1.hash();

ethcore/src/blockchain/update.rs

@@ -17,8 +17,8 @@ pub struct ExtrasUpdate<'a> {
 	pub block_details: HashMap<H256, BlockDetails>,
 	/// Modified block receipts.
 	pub block_receipts: HashMap<H256, BlockReceipts>,
-	/// Modified transaction addresses.
-	pub transactions_addresses: HashMap<H256, TransactionAddress>,
 	/// Modified blocks blooms.
 	pub blocks_blooms: HashMap<LogGroupPosition, BloomGroup>,
+	/// Modified transaction addresses (None signifies removed transactions).
+	pub transactions_addresses: HashMap<H256, Option<TransactionAddress>>,
 }

ethcore/src/client/client.rs

@@ -32,7 +32,7 @@ use util::kvdb::*;
 // other
 use ethkey::recover;
 use io::*;
-use views::{BlockView, HeaderView, BodyView};
+use views::{HeaderView, BodyView};
 use error::{ImportError, ExecutionError, CallError, BlockError, ImportResult, Error as EthcoreError};
 use header::BlockNumber;
 use state::State;
@@ -48,7 +48,7 @@ use transaction::{LocalizedTransaction, SignedTransaction, Action};
 use blockchain::extras::TransactionAddress;
 use types::filter::Filter;
 use log_entry::LocalizedLogEntry;
-use block_queue::{BlockQueue, BlockQueueInfo};
+use verification::queue::{BlockQueue, QueueInfo as BlockQueueInfo};
 use blockchain::{BlockChain, BlockProvider, TreeRoute, ImportRoute};
 use client::{
 	BlockID, TransactionID, UncleID, TraceId, ClientConfig, BlockChainClient,
@@ -67,7 +67,7 @@ use miner::{Miner, MinerService};
 use snapshot::{self, io as snapshot_io};
 use factory::Factories;
 use rlp::{View, UntrustedRlp};
-
+use state_db::StateDB;
 
 // re-export
 pub use types::blockchain_info::BlockChainInfo;
@@ -127,9 +127,9 @@ pub struct Client {
 	tracedb: RwLock<TraceDB<BlockChain>>,
 	engine: Arc<Engine>,
 	config: ClientConfig,
-	db: RwLock<Arc<Database>>,
 	pruning: journaldb::Algorithm,
-	state_db: RwLock<Box<JournalDB>>,
+	db: RwLock<Arc<Database>>,
+	state_db: Mutex<StateDB>,
 	block_queue: BlockQueue,
 	report: RwLock<ClientReport>,
 	import_lock: Mutex<()>,
@@ -173,14 +173,15 @@ impl Client {
 		let chain = Arc::new(BlockChain::new(config.blockchain.clone(), &gb, db.clone()));
 		let tracedb = RwLock::new(TraceDB::new(config.tracing.clone(), db.clone(), chain.clone()));
 
-		let mut state_db = journaldb::new(db.clone(), config.pruning, ::db::COL_STATE);
+		let journal_db = journaldb::new(db.clone(), config.pruning, ::db::COL_STATE);
-		if state_db.is_empty() && try!(spec.ensure_db_good(state_db.as_hashdb_mut())) {
+		let mut state_db = StateDB::new(journal_db);
+		if state_db.journal_db().is_empty() && try!(spec.ensure_db_good(&mut state_db)) {
 			let mut batch = DBTransaction::new(&db);
 			try!(state_db.commit(&mut batch, 0, &spec.genesis_header().hash(), None));
 			try!(db.write(batch).map_err(ClientError::Database));
 		}
 
-		if !chain.block_header(&chain.best_block_hash()).map_or(true, |h| state_db.contains(h.state_root())) {
+		if !chain.block_header(&chain.best_block_hash()).map_or(true, |h| state_db.journal_db().contains(h.state_root())) {
 			warn!("State root not found for block #{} ({})", chain.best_block_number(), chain.best_block_hash().hex());
 		}
 
@@ -209,7 +210,7 @@ impl Client {
 			verifier: verification::new(config.verifier_type.clone()),
 			config: config,
 			db: RwLock::new(db),
-			state_db: RwLock::new(state_db),
+			state_db: Mutex::new(state_db),
 			block_queue: block_queue,
 			report: RwLock::new(Default::default()),
 			import_lock: Mutex::new(()),
@@ -300,7 +301,8 @@ impl Client {
 		// Enact Verified Block
 		let parent = chain_has_parent.unwrap();
 		let last_hashes = self.build_last_hashes(header.parent_hash().clone());
-		let db = self.state_db.read().boxed_clone();
+		let is_canon = header.parent_hash() == &chain.best_block_hash();
+		let db = if is_canon { self.state_db.lock().boxed_clone_canon() } else { self.state_db.lock().boxed_clone() };
 
 		let enact_result = enact_verified(block, engine, self.tracedb.read().tracing_enabled(), db, &parent, last_hashes, self.factories.clone());
 		if let Err(e) = enact_result {
@@ -443,7 +445,8 @@ impl Client {
 		// CHECK! I *think* this is fine, even if the state_root is equal to another
 		// already-imported block of the same number.
 		// TODO: Prove it with a test.
-		block.drain().commit(&mut batch, number, hash, ancient).expect("DB commit failed.");
+		let mut state = block.drain();
+		state.commit(&mut batch, number, hash, ancient).expect("DB commit failed.");
 
 		let route = chain.insert_block(&mut batch, block_data, receipts);
 		self.tracedb.read().import(&mut batch, TraceImportRequest {
@@ -456,7 +459,6 @@ impl Client {
 		// Final commit to the DB
 		self.db.read().write_buffered(batch);
 		chain.commit();
-
 		self.update_last_hashes(&parent, hash);
 		route
 	}
@@ -498,7 +500,7 @@ impl Client {
 		};
 
 		self.block_header(id).and_then(|header| {
-			let db = self.state_db.read().boxed_clone();
+			let db = self.state_db.lock().boxed_clone();
 
 			// early exit for pruned blocks
 			if db.is_pruned() && self.chain.read().best_block_number() >= block_number + HISTORY {
@@ -529,7 +531,7 @@ impl Client {
 	/// Get a copy of the best block's state.
 	pub fn state(&self) -> State {
 		State::from_existing(
-			self.state_db.read().boxed_clone(),
+			self.state_db.lock().boxed_clone(),
 			HeaderView::new(&self.best_block_header()).state_root(),
 			self.engine.account_start_nonce(),
 			self.factories.clone())
@@ -544,7 +546,7 @@ impl Client {
 	/// Get the report.
 	pub fn report(&self) -> ClientReport {
 		let mut report = self.report.read().clone();
-		report.state_db_mem = self.state_db.read().mem_used();
+		report.state_db_mem = self.state_db.lock().mem_used();
 		report
 	}
 
@@ -600,7 +602,7 @@ impl Client {
 	/// Take a snapshot at the given block.
 	/// If the ID given is "latest", this will default to 1000 blocks behind.
 	pub fn take_snapshot<W: snapshot_io::SnapshotWriter + Send>(&self, writer: W, at: BlockID, p: &snapshot::Progress) -> Result<(), EthcoreError> {
-		let db = self.state_db.read().boxed_clone();
+		let db = self.state_db.lock().journal_db().boxed_clone();
 		let best_block_number = self.chain_info().best_block_number;
 		let block_number = try!(self.block_number(at).ok_or(snapshot::Error::InvalidStartingBlock(at)));
 
@@ -679,14 +681,14 @@ impl snapshot::DatabaseRestore for Client {
 		trace!(target: "snapshot", "Replacing client database with {:?}", new_db);
 
 		let _import_lock = self.import_lock.lock();
-		let mut state_db = self.state_db.write();
+		let mut state_db = self.state_db.lock();
 		let mut chain = self.chain.write();
 		let mut tracedb = self.tracedb.write();
 		self.miner.clear();
 		let db = self.db.write();
 		try!(db.restore(new_db));
 
-		*state_db = journaldb::new(db.clone(), self.pruning, ::db::COL_STATE);
+		*state_db = StateDB::new(journaldb::new(db.clone(), self.pruning, ::db::COL_STATE));
 		*chain = Arc::new(BlockChain::new(self.config.blockchain.clone(), &[], db.clone()));
 		*tracedb = TraceDB::new(self.config.tracing.clone(), db.clone(), chain.clone());
 		Ok(())
@@ -806,7 +808,7 @@ impl BlockChainClient for Client {
 		let chain = self.chain.read();
 		match Self::block_hash(&chain, id) {
 			Some(ref hash) if chain.is_known(hash) => BlockStatus::InChain,
-			Some(hash) => self.block_queue.block_status(&hash),
+			Some(hash) => self.block_queue.status(&hash).into(),
 			None => BlockStatus::Unknown
 		}
 	}
@@ -853,9 +855,12 @@ impl BlockChainClient for Client {
 
 	fn transaction_receipt(&self, id: TransactionID) -> Option<LocalizedReceipt> {
 		let chain = self.chain.read();
-		self.transaction_address(id).and_then(|address| chain.block_number(&address.block_hash).and_then(|block_number| {
+		self.transaction_address(id)
+			.and_then(|address| chain.block_number(&address.block_hash).and_then(|block_number| {
 			let t = chain.block_body(&address.block_hash)
-				.and_then(|block| BodyView::new(&block).localized_transaction_at(&address.block_hash, block_number, address.index));
+				.and_then(|block| {
+					BodyView::new(&block).localized_transaction_at(&address.block_hash, block_number, address.index)
+				});
 
 			match (t, chain.transaction_receipt(&address)) {
 				(Some(tx), Some(receipt)) => {
@@ -910,7 +915,7 @@ impl BlockChainClient for Client {
 	}
 
 	fn state_data(&self, hash: &H256) -> Option<Bytes> {
-		self.state_db.read().state(hash)
+		self.state_db.lock().journal_db().state(hash)
 	}
 
 	fn block_receipts(&self, hash: &H256) -> Option<Bytes> {
@@ -918,16 +923,21 @@ impl BlockChainClient for Client {
 	}
 
 	fn import_block(&self, bytes: Bytes) -> Result<H256, BlockImportError> {
+		use verification::queue::kind::HasHash;
+		use verification::queue::kind::blocks::Unverified;
+
+		// create unverified block here so the `sha3` calculation can be cached.
+		let unverified = Unverified::new(bytes);
+
 		{
-			let header = BlockView::new(&bytes).header_view();
+			if self.chain.read().is_known(&unverified.hash()) {
-			if self.chain.read().is_known(&header.sha3()) {
 				return Err(BlockImportError::Import(ImportError::AlreadyInChain));
 			}
-			if self.block_status(BlockID::Hash(header.parent_hash())) == BlockStatus::Unknown {
+			if self.block_status(BlockID::Hash(unverified.parent_hash())) == BlockStatus::Unknown {
-				return Err(BlockImportError::Block(BlockError::UnknownParent(header.parent_hash())));
+				return Err(BlockImportError::Block(BlockError::UnknownParent(unverified.parent_hash())));
 			}
 		}
-		Ok(try!(self.block_queue.import_block(bytes)))
+		Ok(try!(self.block_queue.import(unverified)))
 	}
 
 	fn queue_info(&self) -> BlockQueueInfo {
@@ -1062,7 +1072,7 @@ impl MiningBlockChainClient for Client {
 			engine,
 			self.factories.clone(),
 			false,	// TODO: this will need to be parameterised once we want to do immediate mining insertion.
-			self.state_db.read().boxed_clone(),
+			self.state_db.lock().boxed_clone(),
 			&chain.block_header(&h).expect("h is best block hash: so its header must exist: qed"),
 			self.build_last_hashes(h.clone()),
 			author,

ethcore/src/client/config.rs

@@ -16,11 +16,11 @@
 
 use std::str::FromStr;
 pub use std::time::Duration;
-pub use block_queue::BlockQueueConfig;
 pub use blockchain::Config as BlockChainConfig;
 pub use trace::Config as TraceConfig;
 pub use evm::VMType;
-pub use verification::VerifierType;
+
+use verification::{VerifierType, QueueConfig};
 use util::{journaldb, CompactionProfile};
 use util::trie::TrieSpec;
 
@@ -84,7 +84,7 @@ impl Default for Mode {
 #[derive(Debug, PartialEq, Default)]
 pub struct ClientConfig {
 	/// Block queue configuration.
-	pub queue: BlockQueueConfig,
+	pub queue: QueueConfig,
 	/// Blockchain configuration.
 	pub blockchain: BlockChainConfig,
 	/// Trace configuration.

ethcore/src/client/mod.rs

@@ -23,7 +23,7 @@ mod trace;
 mod client;
 
 pub use self::client::*;
-pub use self::config::{Mode, ClientConfig, DatabaseCompactionProfile, BlockQueueConfig, BlockChainConfig, VMType};
+pub use self::config::{Mode, ClientConfig, DatabaseCompactionProfile, BlockChainConfig, VMType};
 pub use self::error::Error;
 pub use types::ids::*;
 pub use self::test_client::{TestBlockChainClient, EachBlockWith};

ethcore/src/client/test_client.rs

@@ -37,11 +37,12 @@ use evm::{Factory as EvmFactory, VMType};
 use miner::{Miner, MinerService, TransactionImportResult};
 use spec::Spec;
 
-use block_queue::BlockQueueInfo;
+use verification::queue::QueueInfo;
 use block::{OpenBlock, SealedBlock};
 use executive::Executed;
 use error::CallError;
 use trace::LocalizedTrace;
+use state_db::StateDB;
 
 /// Test client.
 pub struct TestBlockChainClient {
@@ -283,13 +284,14 @@ impl TestBlockChainClient {
 	}
 }
 
-pub fn get_temp_journal_db() -> GuardedTempResult<Box<JournalDB>> {
+pub fn get_temp_state_db() -> GuardedTempResult<StateDB> {
 	let temp = RandomTempPath::new();
 	let db = Database::open_default(temp.as_str()).unwrap();
 	let journal_db = journaldb::new(Arc::new(db), journaldb::Algorithm::EarlyMerge, None);
+	let state_db = StateDB::new(journal_db);
 	GuardedTempResult {
 		_temp: temp,
-		result: Some(journal_db)
+		result: Some(state_db)
 	}
 }
 
@@ -297,9 +299,9 @@ impl MiningBlockChainClient for TestBlockChainClient {
 	fn prepare_open_block(&self, author: Address, gas_range_target: (U256, U256), extra_data: Bytes) -> OpenBlock {
 		let engine = &*self.spec.engine;
 		let genesis_header = self.spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		self.spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		self.spec.ensure_db_good(&mut db).unwrap();
 
 		let last_hashes = vec![genesis_header.hash()];
 		let mut open_block = OpenBlock::new(
@@ -383,11 +385,11 @@ impl BlockChainClient for TestBlockChainClient {
 	}
 
 	fn transaction(&self, _id: TransactionID) -> Option<LocalizedTransaction> {
-		unimplemented!();
+		None	// Simple default.
 	}
 
 	fn uncle(&self, _id: UncleID) -> Option<Bytes> {
-		unimplemented!();
+		None	// Simple default.
 	}
 
 	fn transaction_receipt(&self, id: TransactionID) -> Option<LocalizedReceipt> {
@@ -544,8 +546,8 @@ impl BlockChainClient for TestBlockChainClient {
 		Ok(h)
 	}
 
-	fn queue_info(&self) -> BlockQueueInfo {
+	fn queue_info(&self) -> QueueInfo {
-		BlockQueueInfo {
+		QueueInfo {
 			verified_queue_size: self.queue_size.load(AtomicOrder::Relaxed),
 			unverified_queue_size: 0,
 			verifying_queue_size: 0,

ethcore/src/client/traits.rs

@@ -17,7 +17,7 @@
 use std::collections::BTreeMap;
 use util::{U256, Address, H256, H2048, Bytes, Itertools};
 use blockchain::TreeRoute;
-use block_queue::BlockQueueInfo;
+use verification::queue::QueueInfo as BlockQueueInfo;
 use block::{OpenBlock, SealedBlock};
 use header::{BlockNumber};
 use transaction::{LocalizedTransaction, SignedTransaction};

ethcore/src/db.rs

@@ -86,6 +86,9 @@ pub trait Writable {
 	/// Writes the value into the database.
 	fn write<T, R>(&mut self, col: Option<u32>, key: &Key<T, Target = R>, value: &T) where T: rlp::Encodable, R: Deref<Target = [u8]>;
 
+	/// Deletes key from the databse.
+	fn delete<T, R>(&mut self, col: Option<u32>, key: &Key<T, Target = R>) where T: rlp::Encodable, R: Deref<Target = [u8]>;
+
 	/// Writes the value into the database and updates the cache.
 	fn write_with_cache<K, T, R>(&mut self, col: Option<u32>, cache: &mut Cache<K, T>, key: K, value: T, policy: CacheUpdatePolicy) where
 	K: Key<T, Target = R> + Hash + Eq,
@@ -122,6 +125,34 @@ pub trait Writable {
 			},
 		}
 	}
+
+	/// Writes and removes the values into the database and updates the cache.
+	fn extend_with_option_cache<K, T, R>(&mut self, col: Option<u32>, cache: &mut Cache<K, Option<T>>, values: HashMap<K, Option<T>>, policy: CacheUpdatePolicy) where
+	K: Key<T, Target = R> + Hash + Eq,
+	T: rlp::Encodable,
+	R: Deref<Target = [u8]> {
+		match policy {
+			CacheUpdatePolicy::Overwrite => {
+				for (key, value) in values.into_iter() {
+					match value {
+						Some(ref v) => self.write(col, &key, v),
+						None => self.delete(col, &key),
+					}
+					cache.insert(key, value);
+				}
+			},
+			CacheUpdatePolicy::Remove => {
+				for (key, value) in values.into_iter() {
+					match value {
+						Some(v) => self.write(col, &key, &v),
+						None => self.delete(col, &key),
+					}
+					cache.remove(&key);
+				}
+			},
+		}
+	}
+
 }
 
 /// Should be used to read values from database.
@@ -173,6 +204,10 @@ impl Writable for DBTransaction {
 	fn write<T, R>(&mut self, col: Option<u32>, key: &Key<T, Target = R>, value: &T) where T: rlp::Encodable, R: Deref<Target = [u8]> {
 		self.put(col, &key.key(), &rlp::encode(value));
 	}
+
+	fn delete<T, R>(&mut self, col: Option<u32>, key: &Key<T, Target = R>) where T: rlp::Encodable, R: Deref<Target = [u8]> {
+		self.delete(col, &key.key());
+	}
 }
 
 impl Readable for Database {

ethcore/src/engines/basic_authority.rs

@@ -252,9 +252,9 @@ mod tests {
 		let spec = new_test_authority();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let b = OpenBlock::new(engine, Default::default(), false, db, &genesis_header, last_hashes, addr, (3141562.into(), 31415620.into()), vec![]).unwrap();
 		let b = b.close_and_lock();

ethcore/src/engines/instant_seal.rs

@@ -81,9 +81,9 @@ mod tests {
 		let spec = Spec::new_test_instant();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let b = OpenBlock::new(engine, Default::default(), false, db, &genesis_header, last_hashes, addr, (3141562.into(), 31415620.into()), vec![]).unwrap();
 		let b = b.close_and_lock();

ethcore/src/ethereum/ethash.rs

@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
-use ethash::{quick_get_difficulty, EthashManager, H256 as EH256};
+use ethash::{quick_get_difficulty, slow_get_seedhash, EthashManager, H256 as EH256};
 use common::*;
 use block::*;
 use spec::CommonParams;
@@ -32,6 +32,8 @@ pub struct EthashParams {
 	pub minimum_difficulty: U256,
 	/// Difficulty bound divisor.
 	pub difficulty_bound_divisor: U256,
+	/// Difficulty increment divisor.
+	pub difficulty_increment_divisor: u64,
 	/// Block duration.
 	pub duration_limit: u64,
 	/// Block reward.
@@ -46,6 +48,12 @@ pub struct EthashParams {
 	pub dao_hardfork_beneficiary: Address,
 	/// DAO hard-fork DAO accounts list (L)
 	pub dao_hardfork_accounts: Vec<Address>,
+	/// Transition block for a change of difficulty params (currently just bound_divisor).
+	pub difficulty_hardfork_transition: u64,
+	/// Difficulty param after the difficulty transition.
+	pub difficulty_hardfork_bound_divisor: U256,
+	/// Block on which there is no additional difficulty from the exponential bomb.
+	pub bomb_defuse_transition: u64,
 }
 
 impl From<ethjson::spec::EthashParams> for EthashParams {
@@ -54,6 +62,7 @@ impl From<ethjson::spec::EthashParams> for EthashParams {
 			gas_limit_bound_divisor: p.gas_limit_bound_divisor.into(),
 			minimum_difficulty: p.minimum_difficulty.into(),
 			difficulty_bound_divisor: p.difficulty_bound_divisor.into(),
+			difficulty_increment_divisor: p.difficulty_increment_divisor.map_or(10, Into::into),
 			duration_limit: p.duration_limit.into(),
 			block_reward: p.block_reward.into(),
 			registrar: p.registrar.map_or_else(Address::new, Into::into),
@@ -61,6 +70,9 @@ impl From<ethjson::spec::EthashParams> for EthashParams {
 			dao_hardfork_transition: p.dao_hardfork_transition.map_or(0x7fffffffffffffff, Into::into),
 			dao_hardfork_beneficiary: p.dao_hardfork_beneficiary.map_or_else(Address::new, Into::into),
 			dao_hardfork_accounts: p.dao_hardfork_accounts.unwrap_or_else(Vec::new).into_iter().map(Into::into).collect(),
+			difficulty_hardfork_transition: p.difficulty_hardfork_transition.map_or(0x7fffffffffffffff, Into::into),
+			difficulty_hardfork_bound_divisor: p.difficulty_hardfork_bound_divisor.map_or(p.difficulty_bound_divisor.into(), Into::into),
+			bomb_defuse_transition: p.bomb_defuse_transition.map_or(0x7fffffffffffffff, Into::into),
 		}
 	}
 }
@@ -168,6 +180,10 @@ impl Engine for Ethash {
 			fields.state.add_balance(u.author(), &(reward * U256::from(8 + u.number() - current_number) / U256::from(8)));
 		}
 
+		// Commit state so that we can actually figure out the state root.
+		if let Err(e) = fields.state.commit() {
+			warn!("Encountered error on state commit: {}", e);		
+		}		
 	}
 
 	fn verify_block_basic(&self, header: &Header, _block: Option<&[u8]>) -> result::Result<(), Error> {
@@ -217,6 +233,7 @@ impl Engine for Ethash {
 		let result = self.pow.compute_light(header.number() as u64, &Ethash::to_ethash(header.bare_hash()), header.nonce().low_u64());
 		let mix = Ethash::from_ethash(result.mix_hash);
 		let difficulty = Ethash::boundary_to_difficulty(&Ethash::from_ethash(result.value));
+		trace!(target: "miner", "num: {}, seed: {}, h: {}, non: {}, mix: {}, res: {}" , header.number() as u64, Ethash::from_ethash(slow_get_seedhash(header.number() as u64)), header.bare_hash(), header.nonce().low_u64(), Ethash::from_ethash(result.mix_hash), Ethash::from_ethash(result.value));
 		if mix != header.mix_hash() {
 			return Err(From::from(BlockError::MismatchedH256SealElement(Mismatch { expected: mix, found: header.mix_hash() })));
 		}
@@ -267,7 +284,11 @@ impl Ethash {
 		}
 
 		let min_difficulty = self.ethash_params.minimum_difficulty;
-		let difficulty_bound_divisor = self.ethash_params.difficulty_bound_divisor;
+		let difficulty_hardfork = header.number() >= self.ethash_params.difficulty_hardfork_transition;
+		let difficulty_bound_divisor = match difficulty_hardfork {
+			true => self.ethash_params.difficulty_hardfork_bound_divisor,
+			false => self.ethash_params.difficulty_bound_divisor,
+		};
 		let duration_limit = self.ethash_params.duration_limit;
 		let frontier_limit = self.ethash_params.frontier_compatibility_mode_limit;
 
@@ -281,17 +302,19 @@ impl Ethash {
 		else {
 			trace!(target: "ethash", "Calculating difficulty parent.difficulty={}, header.timestamp={}, parent.timestamp={}", parent.difficulty(), header.timestamp(), parent.timestamp());
 			//block_diff = parent_diff + parent_diff // 2048 * max(1 - (block_timestamp - parent_timestamp) // 10, -99)
-			let diff_inc = (header.timestamp() - parent.timestamp()) / 10;
+			let diff_inc = (header.timestamp() - parent.timestamp()) / self.ethash_params.difficulty_increment_divisor;
 			if diff_inc <= 1 {
-				parent.difficulty().clone() + parent.difficulty().clone() / From::from(2048) * From::from(1 - diff_inc)
+				parent.difficulty().clone() + parent.difficulty().clone() / From::from(difficulty_bound_divisor) * From::from(1 - diff_inc)
 			} else {
-				parent.difficulty().clone() - parent.difficulty().clone() / From::from(2048) * From::from(min(diff_inc - 1, 99))
+				parent.difficulty().clone() - parent.difficulty().clone() / From::from(difficulty_bound_divisor) * From::from(min(diff_inc - 1, 99))
 			}
 		};
 		target = max(min_difficulty, target);
-		let period = ((parent.number() + 1) / EXP_DIFF_PERIOD) as usize;
+		if header.number() < self.ethash_params.bomb_defuse_transition {
-		if period > 1 {
+			let period = ((parent.number() + 1) / EXP_DIFF_PERIOD) as usize;
-			target = max(min_difficulty, target + (U256::from(1) << (period - 2)));
+			if period > 1 {
+				target = max(min_difficulty, target + (U256::from(1) << (period - 2)));
+			}
 		}
 		target
 	}
@@ -355,9 +378,9 @@ mod tests {
 		let spec = new_morden();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let b = OpenBlock::new(engine, Default::default(), false, db, &genesis_header, last_hashes, Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
 		let b = b.close();
@@ -369,9 +392,9 @@ mod tests {
 		let spec = new_morden();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let mut b = OpenBlock::new(engine, Default::default(), false, db, &genesis_header, last_hashes, Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
 		let mut uncle = Header::new();

ethcore/src/ethereum/mod.rs

@@ -42,6 +42,9 @@ pub fn new_frontier() -> Spec { load(include_bytes!("../../res/ethereum/frontier
 /// Create a new Frontier mainnet chain spec without the DAO hardfork.
 pub fn new_classic() -> Spec { load(include_bytes!("../../res/ethereum/classic.json")) }
 
+/// Create a new Frontier mainnet chain spec without the DAO hardfork.
+pub fn new_expanse() -> Spec { load(include_bytes!("../../res/ethereum/expanse.json")) }
+
 /// Create a new Frontier chain spec as though it never changes to Homestead.
 pub fn new_frontier_test() -> Spec { load(include_bytes!("../../res/ethereum/frontier_test.json")) }
 
@@ -69,9 +72,9 @@ mod tests {
 		let spec = new_morden();
 		let engine = &spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let s = State::from_existing(db, genesis_header.state_root().clone(), engine.account_start_nonce(), Default::default()).unwrap();
 		assert_eq!(s.balance(&"0000000000000000000000000000000000000001".into()), 1u64.into());
 		assert_eq!(s.balance(&"0000000000000000000000000000000000000002".into()), 1u64.into());

ethcore/src/evm/jit.rs

@@ -196,6 +196,7 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 				receive_address: *const evmjit::H256,
 				code_address: *const evmjit::H256,
 				transfer_value: *const evmjit::I256,
+				// We are ignoring apparent value - it's handled in externalities.
 				_apparent_value: *const evmjit::I256,
 				in_beg: *const u8,
 				in_size: u64,
@@ -208,12 +209,13 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 		let sender_address = unsafe { Address::from_jit(&*sender_address) };
 		let receive_address = unsafe { Address::from_jit(&*receive_address) };
 		let code_address = unsafe { Address::from_jit(&*code_address) };
-		// TODO Is it always safe in case of DELEGATE_CALL?
 		let transfer_value = unsafe { U256::from_jit(&*transfer_value) };
-		let value = Some(transfer_value);
 
 		// receive address and code address are the same in normal calls
 		let is_callcode = receive_address != code_address;
+		let is_delegatecall = is_callcode && sender_address != receive_address;
+
+		let value = if is_delegatecall { None } else { Some(transfer_value) };
 
 		if !is_callcode && !self.ext.exists(&code_address) {
 			gas_cost = gas_cost + U256::from(self.ext.schedule().call_new_account_gas);
@@ -242,10 +244,10 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 			}
 		}
 
-		// TODO [ToDr] Any way to detect DelegateCall?
+		let call_type = match (is_callcode, is_delegatecall) {
-		let call_type = match is_callcode {
+			(_, true) => CallType::DelegateCall,
-			true => CallType::CallCode,
+			(true, false) => CallType::CallCode,
-			false => CallType::Call,
+			(false, false) => CallType::Call,
 		};
 
 		match self.ext.call(

ethcore/src/evm/tests.rs

@@ -141,7 +141,7 @@ impl Ext for FakeExt {
 	}
 
 	fn extcodesize(&self, address: &Address) -> usize {
-		self.codes.get(address).map(|v| v.len()).unwrap_or(0)
+		self.codes.get(address).map_or(0, |c| c.len())
 	}
 
 	fn log(&mut self, topics: Vec<H256>, data: &[u8]) {

ethcore/src/executive.rs

@@ -589,8 +589,11 @@ mod tests {
 		assert_eq!(substate.contracts_created.len(), 0);
 	}
 
-	evm_test!{test_call_to_create: test_call_to_create_jit, test_call_to_create_int}
+	#[test]
-	fn test_call_to_create(factory: Factory) {
+	// Tracing is not suported in JIT
+	fn test_call_to_create() {
+		let factory = Factory::new(VMType::Interpreter);
+
 		// code:
 		//
 		// 7c 601080600c6000396000f3006000355415600957005b60203560003555 - push 29 bytes?
@@ -712,8 +715,10 @@ mod tests {
 		assert_eq!(vm_tracer.drain().unwrap(), expected_vm_trace);
 	}
 
-	evm_test!{test_create_contract: test_create_contract_jit, test_create_contract_int}
+	#[test]
-	fn test_create_contract(factory: Factory) {
+	fn test_create_contract() {
+		// Tracing is not supported in JIT
+		let factory = Factory::new(VMType::Interpreter);
 		// code:
 		//
 		// 60 10 - push 16

ethcore/src/externalities.rs

@@ -209,7 +209,6 @@ impl<'a, T, V> Ext for Externalities<'a, T, V> where T: 'a + Tracer, V: 'a + VMT
 		self.state.code_size(address).unwrap_or(0)
 	}
 
-
 	#[cfg_attr(feature="dev", allow(match_ref_pats))]
 	fn ret(mut self, gas: &U256, data: &[u8]) -> evm::Result<U256>
 		where Self: Sized {

ethcore/src/header.rs

@@ -295,6 +295,12 @@ impl Encodable for Header {
 	}
 }
 
+impl HeapSizeOf for Header {
+	fn heap_size_of_children(&self) -> usize {
+		self.extra_data.heap_size_of_children() + self.seal.heap_size_of_children()
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use rustc_serialize::hex::FromHex;

ethcore/src/lib.rs

@@ -110,6 +110,7 @@ extern crate lazy_static;
 extern crate heapsize;
 #[macro_use]
 extern crate ethcore_ipc as ipc;
+extern crate lru_cache;
 
 #[cfg(feature = "jit" )]
 extern crate evmjit;
@@ -119,7 +120,6 @@ pub extern crate ethstore;
 pub mod account_provider;
 pub mod engines;
 pub mod block;
-pub mod block_queue;
 pub mod client;
 pub mod error;
 pub mod ethereum;
@@ -143,6 +143,7 @@ mod basic_types;
 mod env_info;
 mod pod_account;
 mod state;
+mod state_db;
 mod account_db;
 mod builtin;
 mod executive;

ethcore/src/miner/miner.rs

@@ -864,15 +864,24 @@ impl MinerService for Miner {
 	}
 
 	fn submit_seal(&self, chain: &MiningBlockChainClient, pow_hash: H256, seal: Vec<Bytes>) -> Result<(), Error> {
-		let result = if let Some(b) = self.sealing_work.lock().queue.get_used_if(if self.options.enable_resubmission { GetAction::Clone } else { GetAction::Take }, |b| &b.hash() == &pow_hash) {
+		let result =
-			b.lock().try_seal(&*self.engine, seal).or_else(|_| {
+			if let Some(b) = self.sealing_work.lock().queue.get_used_if(
-				warn!(target: "miner", "Mined solution rejected: Invalid.");
+				if self.options.enable_resubmission {
-				Err(Error::PowInvalid)
+					GetAction::Clone
-			})
+				} else {
-		} else {
+					GetAction::Take
-			warn!(target: "miner", "Mined solution rejected: Block unknown or out of date.");
+				},
-			Err(Error::PowHashInvalid)
+				|b| &b.hash() == &pow_hash
-		};
+			) {
+				trace!(target: "miner", "Sealing block {}={}={} with seal {:?}", pow_hash, b.hash(), b.header().bare_hash(), seal);
+				b.lock().try_seal(&*self.engine, seal).or_else(|(e, _)| {
+					warn!(target: "miner", "Mined solution rejected: {}", e);
+					Err(Error::PowInvalid)
+				})
+			} else {
+				warn!(target: "miner", "Mined solution rejected: Block unknown or out of date.");
+				Err(Error::PowHashInvalid)
+			};
 		result.and_then(|sealed| {
 			let n = sealed.header().number();
 			let h = sealed.header().hash();
@@ -915,7 +924,7 @@ impl MinerService for Miner {
 			out_of_chain.for_each(|txs| {
 				let mut transaction_queue = self.transaction_queue.lock();
 				let _ = self.add_transactions_to_queue(
-					chain, txs, TransactionOrigin::External, &mut transaction_queue
+					chain, txs, TransactionOrigin::RetractedBlock, &mut transaction_queue
 				);
 			});
 		}

ethcore/src/miner/transaction_queue.rs

@@ -98,6 +98,8 @@ pub enum TransactionOrigin {
 	Local,
 	/// External transaction received from network
 	External,
+	/// Transactions from retracted blocks
+	RetractedBlock,
 }
 
 impl PartialOrd for TransactionOrigin {
@@ -112,10 +114,11 @@ impl Ord for TransactionOrigin {
 			return Ordering::Equal;
 		}
 
-		if *self == TransactionOrigin::Local {
+		match (*self, *other) {
-			Ordering::Less
+			(TransactionOrigin::RetractedBlock, _) => Ordering::Less,
-		} else {
+			(_, TransactionOrigin::RetractedBlock) => Ordering::Greater,
-			Ordering::Greater
+			(TransactionOrigin::Local, _) => Ordering::Less,
+			_ => Ordering::Greater,
 		}
 	}
 }
@@ -711,7 +714,10 @@ impl TransactionQueue {
 			let order = self.current.drop(sender, &k).expect("iterating over a collection that has been retrieved above;
 															 qed");
 			if k >= current_nonce {
-				self.future.insert(*sender, k, order.update_height(k, current_nonce));
+				let order = order.update_height(k, current_nonce);
+				if let Some(old) = self.future.insert(*sender, k, order.clone()) {
+					Self::replace_orders(*sender, k, old, order, &mut self.future, &mut self.by_hash);
+				}
 			} else {
 				trace!(target: "txqueue", "Removing old transaction: {:?} (nonce: {} < {})", order.hash, k, current_nonce);
 				self.by_hash.remove(&order.hash).expect("All transactions in `future` are also in `by_hash`");
@@ -776,7 +782,9 @@ impl TransactionQueue {
 				self.future.by_gas_price.remove(&order.gas_price, &order.hash);
 				// Put to current
 				let order = order.update_height(current_nonce, first_nonce);
-				self.current.insert(address, current_nonce, order);
+				if let Some(old) = self.current.insert(address, current_nonce, order.clone()) {
+					Self::replace_orders(address, current_nonce, old, order, &mut self.current, &mut self.by_hash);
+				}
 				update_last_nonce_to = Some(current_nonce);
 				current_nonce = current_nonce + U256::one();
 			}
@@ -810,47 +818,49 @@ impl TransactionQueue {
 		let nonce = tx.nonce();
 		let hash = tx.hash();
 
-		let next_nonce = self.last_nonces
-			.get(&address)
-			.cloned()
-			.map_or(state_nonce, |n| n + U256::one());
-
 		// The transaction might be old, let's check that.
 		// This has to be the first test, otherwise calculating
 		// nonce height would result in overflow.
 		if nonce < state_nonce {
 			// Droping transaction
-			trace!(target: "txqueue", "Dropping old transaction: {:?} (nonce: {} < {})", tx.hash(), nonce, next_nonce);
+			trace!(target: "txqueue", "Dropping old transaction: {:?} (nonce: {} < {})", tx.hash(), nonce, state_nonce);
 			return Err(TransactionError::Old);
-		} else if nonce > next_nonce {
+		}
+
+		// Update nonces of transactions in future (remove old transactions)
+		self.update_future(&address, state_nonce);
+		// State nonce could be updated. Maybe there are some more items waiting in future?
+		self.move_matching_future_to_current(address, state_nonce, state_nonce);
+		// Check the next expected nonce (might be updated by move above)
+		let next_nonce = self.last_nonces
+			.get(&address)
+			.cloned()
+			.map_or(state_nonce, |n| n + U256::one());
+
+		// Future transaction
+		if nonce > next_nonce {
 			// We have a gap - put to future.
-			// Update nonces of transactions in future (remove old transactions)
-			self.update_future(&address, state_nonce);
 			// Insert transaction (or replace old one with lower gas price)
 			try!(check_too_cheap(Self::replace_transaction(tx, state_nonce, &mut self.future, &mut self.by_hash)));
-			// Return an error if this transaction is not imported because of limit.
+			// Enforce limit in Future
-			try!(check_if_removed(&address, &nonce, self.future.enforce_limit(&mut self.by_hash)));
+			let removed = self.future.enforce_limit(&mut self.by_hash);
+			// Return an error if this transaction was not imported because of limit.
+			try!(check_if_removed(&address, &nonce, removed));
 
 			debug!(target: "txqueue", "Importing transaction to future: {:?}", hash);
 			debug!(target: "txqueue", "status: {:?}", self.status());
 			return Ok(TransactionImportResult::Future);
 		}
+
+		// We might have filled a gap - move some more transactions from future
+		self.move_matching_future_to_current(address, nonce, state_nonce);
+		self.move_matching_future_to_current(address, nonce + U256::one(), state_nonce);
+
+		// Replace transaction if any
 		try!(check_too_cheap(Self::replace_transaction(tx, state_nonce, &mut self.current, &mut self.by_hash)));
 		// Keep track of highest nonce stored in current
 		let new_max = self.last_nonces.get(&address).map_or(nonce, |n| cmp::max(nonce, *n));
 		self.last_nonces.insert(address, new_max);
-		// Update nonces of transactions in future
-		self.update_future(&address, state_nonce);
-		// Maybe there are some more items waiting in future?
-		self.move_matching_future_to_current(address, nonce + U256::one(), state_nonce);
-		// There might be exactly the same transaction waiting in future
-		// same (sender, nonce), but above function would not move it.
-		if let Some(order) = self.future.drop(&address, &nonce) {
-			// Let's insert that transaction to current (if it has higher gas_price)
-			let future_tx = self.by_hash.remove(&order.hash).expect("All transactions in `future` are always in `by_hash`.");
-			// if transaction in `current` (then one we are importing) is replaced it means that it has to low gas_price
-			try!(check_too_cheap(!Self::replace_transaction(future_tx, state_nonce, &mut self.current, &mut self.by_hash)));
-		}
 
 		// Also enforce the limit
 		let removed = self.current.enforce_limit(&mut self.by_hash);
@@ -895,24 +905,28 @@ impl TransactionQueue {
 
 
 		if let Some(old) = set.insert(address, nonce, order.clone()) {
-			// There was already transaction in queue. Let's check which one should stay
+			Self::replace_orders(address, nonce, old, order, set, by_hash)
-			let old_fee = old.gas_price;
-			let new_fee = order.gas_price;
-			if old_fee.cmp(&new_fee) == Ordering::Greater {
-				// Put back old transaction since it has greater priority (higher gas_price)
-				set.insert(address, nonce, old);
-				// and remove new one
-				by_hash.remove(&hash).expect("The hash has been just inserted and no other line is altering `by_hash`.");
-				false
-			} else {
-				// Make sure we remove old transaction entirely
-				by_hash.remove(&old.hash).expect("The hash is coming from `future` so it has to be in `by_hash`.");
-				true
-			}
 		} else {
 			true
 		}
 	}
+
+	fn replace_orders(address: Address, nonce: U256, old: TransactionOrder, order: TransactionOrder, set: &mut TransactionSet, by_hash: &mut HashMap<H256, VerifiedTransaction>) -> bool {
+		// There was already transaction in queue. Let's check which one should stay
+		let old_fee = old.gas_price;
+		let new_fee = order.gas_price;
+		if old_fee.cmp(&new_fee) == Ordering::Greater {
+			// Put back old transaction since it has greater priority (higher gas_price)
+			set.insert(address, nonce, old);
+			// and remove new one
+			by_hash.remove(&order.hash).expect("The hash has been just inserted and no other line is altering `by_hash`.");
+			false
+		} else {
+			// Make sure we remove old transaction entirely
+			by_hash.remove(&old.hash).expect("The hash is coming from `future` so it has to be in `by_hash`.");
+			true
+		}
+	}
 }
 
 fn check_too_cheap(is_in: bool) -> Result<(), TransactionError> {
@@ -1014,6 +1028,17 @@ mod test {
 		new_tx_pair_default(0.into(), 1.into())
 	}
 
+	#[test]
+	fn test_ordering() {
+		assert_eq!(TransactionOrigin::Local.cmp(&TransactionOrigin::External), Ordering::Less);
+		assert_eq!(TransactionOrigin::RetractedBlock.cmp(&TransactionOrigin::Local), Ordering::Less);
+		assert_eq!(TransactionOrigin::RetractedBlock.cmp(&TransactionOrigin::External), Ordering::Less);
+
+		assert_eq!(TransactionOrigin::External.cmp(&TransactionOrigin::Local), Ordering::Greater);
+		assert_eq!(TransactionOrigin::Local.cmp(&TransactionOrigin::RetractedBlock), Ordering::Greater);
+		assert_eq!(TransactionOrigin::External.cmp(&TransactionOrigin::RetractedBlock), Ordering::Greater);
+	}
+
 	#[test]
 	fn should_return_correct_nonces_when_dropped_because_of_limit() {
 		// given
@@ -1196,6 +1221,31 @@ mod test {
 		assert_eq!(txq.top_transactions()[0], tx2);
 	}
 
+	#[test]
+	fn should_move_all_transactions_from_future() {
+		// given
+		let mut txq = TransactionQueue::new();
+		let (tx, tx2) = new_tx_pair_default(1.into(), 1.into());
+		let prev_nonce = |a: &Address| AccountDetails{ nonce: default_account_details(a).nonce - U256::one(), balance:
+			!U256::zero() };
+
+		// First insert one transaction to future
+		let res = txq.add(tx.clone(), &prev_nonce, TransactionOrigin::External);
+		assert_eq!(res.unwrap(), TransactionImportResult::Future);
+		assert_eq!(txq.status().future, 1);
+
+		// now import second transaction to current
+		let res = txq.add(tx2.clone(), &default_account_details, TransactionOrigin::External);
+
+		// then
+		assert_eq!(res.unwrap(), TransactionImportResult::Current);
+		assert_eq!(txq.status().pending, 2);
+		assert_eq!(txq.status().future, 0);
+		assert_eq!(txq.current.by_priority.len(), 2);
+		assert_eq!(txq.current.by_address.len(), 2);
+		assert_eq!(txq.top_transactions()[0], tx);
+		assert_eq!(txq.top_transactions()[1], tx2);
+	}
 
 	#[test]
 	fn should_import_tx() {
@@ -1375,6 +1425,27 @@ mod test {
 		assert_eq!(top.len(), 2);
 	}
 
+	#[test]
+	fn should_prioritize_reimported_transactions_within_same_nonce_height() {
+		// given
+		let mut txq = TransactionQueue::new();
+		let tx = new_tx_default();
+		// the second one has same nonce but higher `gas_price`
+		let (_, tx2) = new_similar_tx_pair();
+
+		// when
+		// first insert local one with higher gas price
+		txq.add(tx2.clone(), &default_account_details, TransactionOrigin::Local).unwrap();
+		// then the one with lower gas price, but from retracted block
+		txq.add(tx.clone(), &default_account_details, TransactionOrigin::RetractedBlock).unwrap();
+
+		// then
+		let top = txq.top_transactions();
+		assert_eq!(top[0], tx); // retracted should be first
+		assert_eq!(top[1], tx2);
+		assert_eq!(top.len(), 2);
+	}
+
 	#[test]
 	fn should_not_prioritize_local_transactions_with_different_nonce_height() {
 		// given

ethcore/src/pod_account.rs

@@ -48,7 +48,7 @@ impl PodAccount {
 		PodAccount {
 			balance: *acc.balance(),
 			nonce: *acc.nonce(),
-			storage: acc.storage_overlay().iter().fold(BTreeMap::new(), |mut m, (k, &(_, ref v))| {m.insert(k.clone(), v.clone()); m}),
+			storage: acc.storage_changes().iter().fold(BTreeMap::new(), |mut m, (k, v)| {m.insert(k.clone(), v.clone()); m}),
 			code: acc.code().map(|x| x.to_vec()),
 		}
 	}

ethcore/src/service.rs

@@ -80,7 +80,13 @@ impl ClientService {
 		}
 
 		let mut db_config = DatabaseConfig::with_columns(::db::NUM_COLUMNS);
-		db_config.cache_size = config.db_cache_size;
+
+		// give all rocksdb cache to state column; everything else has its
+		// own caches.
+		if let Some(size) = config.db_cache_size {
+			db_config.set_cache(::db::COL_STATE, size);
+		}
+
 		db_config.compaction = config.db_compaction.compaction_profile();
 		db_config.wal = config.db_wal;
 
@@ -90,7 +96,7 @@ impl ClientService {
 		let snapshot_params = SnapServiceParams {
 			engine: spec.engine.clone(),
 			genesis_block: spec.genesis_block(),
-			db_config: db_config,
+			db_config: db_config.clone(),
 			pruning: pruning,
 			channel: io_service.channel(),
 			snapshot_root: snapshot_path.into(),

ethcore/src/snapshot/account.rs

@@ -205,7 +205,7 @@ impl Account {
 #[cfg(test)]
 mod tests {
 	use account_db::{AccountDB, AccountDBMut};
-	use tests::helpers::get_temp_journal_db;
+	use tests::helpers::get_temp_state_db;
 	use snapshot::tests::helpers::fill_storage;
 
 	use util::sha3::{SHA3_EMPTY, SHA3_NULL_RLP};
@@ -218,8 +218,7 @@ mod tests {
 
 	#[test]
 	fn encoding_basic() {
-		let mut db = get_temp_journal_db();
+		let mut db = get_temp_state_db();
-		let mut db = &mut **db;
 		let addr = Address::random();
 
 		let account = Account {
@@ -239,8 +238,7 @@ mod tests {
 
 	#[test]
 	fn encoding_storage() {
-		let mut db = get_temp_journal_db();
+		let mut db = get_temp_state_db();
-		let mut db = &mut **db;
 		let addr = Address::random();
 
 		let account = {
@@ -265,8 +263,7 @@ mod tests {
 
 	#[test]
 	fn encoding_code() {
-		let mut db = get_temp_journal_db();
+		let mut db = get_temp_state_db();
-		let mut db = &mut **db;
 
 		let addr1 = Address::random();
 		let addr2 = Address::random();

ethcore/src/spec/spec.rs

@@ -20,6 +20,7 @@ use common::*;
 use engines::{Engine, NullEngine, InstantSeal, BasicAuthority, Tendermint};
 use pod_state::*;
 use account_db::*;
+use state_db::StateDB;
 use super::genesis::Genesis;
 use super::seal::Generic as GenericSeal;
 use ethereum;
@@ -36,6 +37,8 @@ pub struct CommonParams {
 	pub maximum_extra_data_size: usize,
 	/// Network id.
 	pub network_id: U256,
+	/// Main subprotocol name.
+	pub subprotocol_name: String,
 	/// Minimum gas limit.
 	pub min_gas_limit: U256,
 	/// Fork block to check.
@@ -48,6 +51,7 @@ impl From<ethjson::spec::Params> for CommonParams {
 			account_start_nonce: p.account_start_nonce.into(),
 			maximum_extra_data_size: p.maximum_extra_data_size.into(),
 			network_id: p.network_id.into(),
+			subprotocol_name: p.subprotocol_name.unwrap_or_else(|| "eth".to_owned()),
 			min_gas_limit: p.min_gas_limit.into(),
 			fork_block: if let (Some(n), Some(h)) = (p.fork_block, p.fork_hash) { Some((n.into(), h.into())) } else { None },
 		}
@@ -156,6 +160,9 @@ impl Spec {
 	/// Get the configured Network ID.
 	pub fn network_id(&self) -> U256 { self.params.network_id }
 
+	/// Get the configured Network ID.
+	pub fn subprotocol_name(&self) -> String { self.params.subprotocol_name.clone() }
+
 	/// Get the configured network fork block.
 	pub fn fork_block(&self) -> Option<(BlockNumber, H256)> { self.params.fork_block }
 
@@ -169,7 +176,7 @@ impl Spec {
 		header.set_transactions_root(self.transactions_root.clone());
 		header.set_uncles_hash(RlpStream::new_list(0).out().sha3());
 		header.set_extra_data(self.extra_data.clone());
-		header.set_state_root(self.state_root().clone());
+		header.set_state_root(self.state_root());
 		header.set_receipts_root(self.receipts_root.clone());
 		header.set_log_bloom(H2048::new().clone());
 		header.set_gas_used(self.gas_used.clone());
@@ -184,6 +191,7 @@ impl Spec {
 			let r = Rlp::new(&seal);
 			(0..self.seal_fields).map(|i| r.at(i).as_raw().to_vec()).collect()
 		});
+		trace!(target: "spec", "Header hash is {}", header.hash());
 		header
 	}
 
@@ -227,19 +235,22 @@ impl Spec {
 	}
 
 	/// Ensure that the given state DB has the trie nodes in for the genesis state.
-	pub fn ensure_db_good(&self, db: &mut HashDB) -> Result<bool, Box<TrieError>> {
+	pub fn ensure_db_good(&self, db: &mut StateDB) -> Result<bool, Box<TrieError>> {
-		if !db.contains(&self.state_root()) {
+		if !db.as_hashdb().contains(&self.state_root()) {
+			trace!(target: "spec", "ensure_db_good: Fresh database? Cannot find state root {}", self.state_root());
 			let mut root = H256::new();
+
 			{
-				let mut t = SecTrieDBMut::new(db, &mut root);
+				let mut t = SecTrieDBMut::new(db.as_hashdb_mut(), &mut root);
 				for (address, account) in self.genesis_state.get().iter() {
 					try!(t.insert(&**address, &account.rlp()));
 				}
 			}
+			trace!(target: "spec", "ensure_db_good: Populated sec trie; root is {}", root);
 			for (address, account) in self.genesis_state.get().iter() {
-				account.insert_additional(&mut AccountDBMut::new(db, address));
+				account.insert_additional(&mut AccountDBMut::new(db.as_hashdb_mut(), address));
 			}
-			assert!(db.contains(&self.state_root()));
+			assert!(db.as_hashdb().contains(&self.state_root()));
 			Ok(true)
 		} else { Ok(false) }
 	}

ethcore/src/state/account.rs

@@ -20,11 +20,13 @@ use std::collections::hash_map::Entry;
 use util::*;
 use pod_account::*;
 use rlp::*;
+use lru_cache::LruCache;
 
-use std::cell::{Ref, RefCell, Cell};
+use std::cell::{RefCell, Cell};
+
+const STORAGE_CACHE_ITEMS: usize = 4096;
 
 /// Single account in the system.
-#[derive(Clone)]
 pub struct Account {
 	// Balance of the account.
 	balance: U256,
@@ -32,10 +34,16 @@ pub struct Account {
 	nonce: U256,
 	// Trie-backed storage.
 	storage_root: H256,
-	// Overlay on trie-backed storage - tuple is (<clean>, <value>).
+	// LRU Cache of the trie-backed storage.
-	storage_overlay: RefCell<HashMap<H256, (Filth, H256)>>,
+	// This is limited to `STORAGE_CACHE_ITEMS` recent queries
+	storage_cache: RefCell<LruCache<H256, H256>>,
+	// Modified storage. Accumulates changes to storage made in `set_storage`
+	// Takes precedence over `storage_cache`.
+	storage_changes: HashMap<H256, H256>,
 	// Code hash of the account. If None, means that it's a contract whose code has not yet been set.
 	code_hash: Option<H256>,
+	// Size of the accoun code.
+	code_size: Option<usize>,
 	// Code cache of the account.
 	code_cache: Bytes,
 	// Account is new or has been modified
@@ -52,23 +60,31 @@ impl Account {
 			balance: balance,
 			nonce: nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(storage.into_iter().map(|(k, v)| (k, (Filth::Dirty, v))).collect()),
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: storage,
 			code_hash: Some(code.sha3()),
+			code_size: Some(code.len()),
 			code_cache: code,
 			filth: Filth::Dirty,
 			address_hash: Cell::new(None),
 		}
 	}
 
+	fn empty_storage_cache() -> RefCell<LruCache<H256, H256>> {
+		RefCell::new(LruCache::new(STORAGE_CACHE_ITEMS))
+	}
+
 	/// General constructor.
 	pub fn from_pod(pod: PodAccount) -> Account {
 		Account {
 			balance: pod.balance,
 			nonce: pod.nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(pod.storage.into_iter().map(|(k, v)| (k, (Filth::Dirty, v))).collect()),
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: pod.storage.into_iter().collect(),
 			code_hash: pod.code.as_ref().map(|c| c.sha3()),
-			code_cache: pod.code.as_ref().map_or_else(|| { warn!("POD account with unknown code is being created! Assuming no code."); vec![] }, |c| c.clone()),
+			code_size: Some(pod.code.as_ref().map_or(0, |c| c.len())),
+			code_cache: pod.code.map_or_else(|| { warn!("POD account with unknown code is being created! Assuming no code."); vec![] }, |c| c),
 			filth: Filth::Dirty,
 			address_hash: Cell::new(None),
 		}
@@ -80,9 +96,11 @@ impl Account {
 			balance: balance,
 			nonce: nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(HashMap::new()),
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
 			code_hash: Some(SHA3_EMPTY),
 			code_cache: vec![],
+			code_size: Some(0),
 			filth: Filth::Dirty,
 			address_hash: Cell::new(None),
 		}
@@ -95,9 +113,11 @@ impl Account {
 			nonce: r.val_at(0),
 			balance: r.val_at(1),
 			storage_root: r.val_at(2),
-			storage_overlay: RefCell::new(HashMap::new()),
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
 			code_hash: Some(r.val_at(3)),
 			code_cache: vec![],
+			code_size: None,
 			filth: Filth::Clean,
 			address_hash: Cell::new(None),
 		}
@@ -110,9 +130,11 @@ impl Account {
 			balance: balance,
 			nonce: nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(HashMap::new()),
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
 			code_hash: None,
 			code_cache: vec![],
+			code_size: None,
 			filth: Filth::Dirty,
 			address_hash: Cell::new(None),
 		}
@@ -123,44 +145,62 @@ impl Account {
 	pub fn init_code(&mut self, code: Bytes) {
 		assert!(self.code_hash.is_none());
 		self.code_cache = code;
+		self.code_size = Some(self.code_cache.len());
 		self.filth = Filth::Dirty;
 	}
 
 	/// Reset this account's code to the given code.
 	pub fn reset_code(&mut self, code: Bytes) {
 		self.code_hash = None;
+		self.code_size = Some(0);
 		self.init_code(code);
 	}
 
 	/// Set (and cache) the contents of the trie's storage at `key` to `value`.
 	pub fn set_storage(&mut self, key: H256, value: H256) {
-		match self.storage_overlay.borrow_mut().entry(key) {
+		match self.storage_changes.entry(key) {
-			Entry::Occupied(ref mut entry) if entry.get().1 != value => {
+			Entry::Occupied(ref mut entry) if entry.get() != &value => {
-				entry.insert((Filth::Dirty, value));
+				entry.insert(value);
 				self.filth = Filth::Dirty;
 			},
 			Entry::Vacant(entry) => {
-				entry.insert((Filth::Dirty, value));
+				entry.insert(value);
 				self.filth = Filth::Dirty;
 			},
-			_ => (),
+			_ => {},
 		}
 	}
 
 	/// Get (and cache) the contents of the trie's storage at `key`.
+	/// Takes modifed storage into account.
 	pub fn storage_at(&self, db: &HashDB, key: &H256) -> H256 {
-		self.storage_overlay.borrow_mut().entry(key.clone()).or_insert_with(||{
+		if let Some(value) = self.cached_storage_at(key) {
-			let db = SecTrieDB::new(db, &self.storage_root)
+			return value;
-				.expect("Account storage_root initially set to zero (valid) and only altered by SecTrieDBMut. \
+		}
-				SecTrieDBMut would not set it to an invalid state root. Therefore the root is valid and DB creation \
+		let db = SecTrieDB::new(db, &self.storage_root)
-				using it will not fail.");
+			.expect("Account storage_root initially set to zero (valid) and only altered by SecTrieDBMut. \
+			SecTrieDBMut would not set it to an invalid state root. Therefore the root is valid and DB creation \
+			using it will not fail.");
 
-			let item: U256 = match db.get(key){
+		let item: U256 = match db.get(key){
-				Ok(x) => x.map_or_else(U256::zero, decode),
+			Ok(x) => x.map_or_else(U256::zero, decode),
-				Err(e) => panic!("Encountered potential DB corruption: {}", e),
+			Err(e) => panic!("Encountered potential DB corruption: {}", e),
-			};
+		};
-			(Filth::Clean, item.into())
+		let value: H256 = item.into();
-		}).1.clone()
+		self.storage_cache.borrow_mut().insert(key.clone(), value.clone());
+		value
+	}
+
+	/// Get cached storage value if any. Returns `None` if the
+	/// key is not in the cache.
+	pub fn cached_storage_at(&self, key: &H256) -> Option<H256> {
+		if let Some(value) = self.storage_changes.get(key) {
+			return Some(value.clone())
+		}
+		if let Some(value) = self.storage_cache.borrow_mut().get_mut(key) {
+			return Some(value.clone())
+		}
+		None
 	}
 
 	/// return the balance associated with this account.
@@ -196,6 +236,12 @@ impl Account {
 		}
 	}
 
+	/// returns the account's code size. If `None` then the code cache or code size cache isn't available -
+	/// get someone who knows to call `note_code`.
+	pub fn code_size(&self) -> Option<usize> {
+		self.code_size.clone()
+	}
+
 	#[cfg(test)]
 	/// Provide a byte array which hashes to the `code_hash`. returns the hash as a result.
 	pub fn note_code(&mut self, code: Bytes) -> Result<(), H256> {
@@ -203,6 +249,7 @@ impl Account {
 		match self.code_hash {
 			Some(ref i) if h == *i => {
 				self.code_cache = code;
+				self.code_size = Some(self.code_cache.len());
 				Ok(())
 			},
 			_ => Err(h)
@@ -216,11 +263,12 @@ impl Account {
 
 	/// Is this a new or modified account?
 	pub fn is_dirty(&self) -> bool {
-		self.filth == Filth::Dirty
+		self.filth == Filth::Dirty || !self.storage_is_clean()
 	}
 
 	/// Mark account as clean.
 	pub fn set_clean(&mut self) {
+		assert!(self.storage_is_clean());
 		self.filth = Filth::Clean
 	}
 
@@ -231,7 +279,31 @@ impl Account {
 		self.is_cached() ||
 			match self.code_hash {
 				Some(ref h) => match db.get(h) {
-					Some(x) => { self.code_cache = x.to_vec(); true },
+					Some(x) => {
+						self.code_cache = x.to_vec();
+						self.code_size = Some(x.len());
+						true
+					},
+					_ => {
+						warn!("Failed reverse get of {}", h);
+						false
+					},
+				},
+				_ => false,
+			}
+	}
+
+	/// Provide a database to get `code_size`. Should not be called if it is a contract without code.
+	pub fn cache_code_size(&mut self, db: &HashDB) -> bool {
+		// TODO: fill out self.code_cache;
+		trace!("Account::cache_code_size: ic={}; self.code_hash={:?}, self.code_cache={}", self.is_cached(), self.code_hash, self.code_cache.pretty());
+		self.code_size.is_some() ||
+			match self.code_hash {
+				Some(ref h) if h != &SHA3_EMPTY => match db.get(h) {
+					Some(x) => {
+						self.code_size = Some(x.len());
+						true
+					},
 					_ => {
 						warn!("Failed reverse get of {}", h);
 						false
@@ -241,16 +313,15 @@ impl Account {
 			}
 	}
 
-	#[cfg(test)]
 	/// Determine whether there are any un-`commit()`-ed storage-setting operations.
-	pub fn storage_is_clean(&self) -> bool { self.storage_overlay.borrow().iter().find(|&(_, &(f, _))| f == Filth::Dirty).is_none() }
+	pub fn storage_is_clean(&self) -> bool { self.storage_changes.is_empty() }
 
 	#[cfg(test)]
 	/// return the storage root associated with this account or None if it has been altered via the overlay.
 	pub fn storage_root(&self) -> Option<&H256> { if self.storage_is_clean() {Some(&self.storage_root)} else {None} }
 
 	/// return the storage overlay.
-	pub fn storage_overlay(&self) -> Ref<HashMap<H256, (Filth, H256)>> { self.storage_overlay.borrow() }
+	pub fn storage_changes(&self) -> &HashMap<H256, H256> { &self.storage_changes }
 
 	/// Increment the nonce of the account by one.
 	pub fn inc_nonce(&mut self) {
@@ -276,26 +347,24 @@ impl Account {
 		}
 	}
 
-	/// Commit the `storage_overlay` to the backing DB and update `storage_root`.
+	/// Commit the `storage_changes` to the backing DB and update `storage_root`.
 	pub fn commit_storage(&mut self, trie_factory: &TrieFactory, db: &mut HashDB) {
 		let mut t = trie_factory.from_existing(db, &mut self.storage_root)
 			.expect("Account storage_root initially set to zero (valid) and only altered by SecTrieDBMut. \
 				SecTrieDBMut would not set it to an invalid state root. Therefore the root is valid and DB creation \
 				using it will not fail.");
-		for (k, &mut (ref mut f, ref mut v)) in self.storage_overlay.borrow_mut().iter_mut() {
+		for (k, v) in self.storage_changes.drain() {
-			if f == &Filth::Dirty {
+			// cast key and value to trait type,
-				// cast key and value to trait type,
+			// so we can call overloaded `to_bytes` method
-				// so we can call overloaded `to_bytes` method
+			let res = match v.is_zero() {
-				let res = match v.is_zero() {
+				true => t.remove(&k),
-					true => t.remove(k),
+				false => t.insert(&k, &encode(&U256::from(&*v))),
-					false => t.insert(k, &encode(&U256::from(&*v))),
+			};
-				};
 
-				if let Err(e) = res {
+			if let Err(e) = res {
-					warn!("Encountered potential DB corruption: {}", e);
+				warn!("Encountered potential DB corruption: {}", e);
-				}
-				*f = Filth::Clean;
 			}
+			self.storage_cache.borrow_mut().insert(k, v);
 		}
 	}
 
@@ -303,9 +372,13 @@ impl Account {
 	pub fn commit_code(&mut self, db: &mut HashDB) {
 		trace!("Commiting code of {:?} - {:?}, {:?}", self, self.code_hash.is_none(), self.code_cache.is_empty());
 		match (self.code_hash.is_none(), self.code_cache.is_empty()) {
-			(true, true) => self.code_hash = Some(SHA3_EMPTY),
+			(true, true) => {
+				self.code_hash = Some(SHA3_EMPTY);
+				self.code_size = Some(0);
+			},
 			(true, false) => {
 				self.code_hash = Some(db.insert(&self.code_cache));
+				self.code_size = Some(self.code_cache.len());
 			},
 			(false, _) => {},
 		}
@@ -317,9 +390,57 @@ impl Account {
 		stream.append(&self.nonce);
 		stream.append(&self.balance);
 		stream.append(&self.storage_root);
-		stream.append(self.code_hash.as_ref().expect("Cannot form RLP of contract account without code."));
+		stream.append(self.code_hash.as_ref().unwrap_or(&SHA3_EMPTY));
 		stream.out()
 	}
+
+	/// Clone basic account data
+	pub fn clone_basic(&self) -> Account {
+		Account {
+			balance: self.balance.clone(),
+			nonce: self.nonce.clone(),
+			storage_root: self.storage_root.clone(),
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
+			code_hash: self.code_hash.clone(),
+			code_size: self.code_size.clone(),
+			code_cache: Bytes::new(),
+			filth: self.filth,
+			address_hash: self.address_hash.clone(),
+		}
+	}
+
+	/// Clone account data and dirty storage keys
+	pub fn clone_dirty(&self) -> Account {
+		let mut account = self.clone_basic();
+		account.storage_changes = self.storage_changes.clone();
+		account.code_cache = self.code_cache.clone();
+		account
+	}
+
+	/// Clone account data, dirty storage keys and cached storage keys.
+	pub fn clone_all(&self) -> Account {
+		let mut account = self.clone_dirty();
+		account.storage_cache = self.storage_cache.clone();
+		account
+	}
+
+	/// Replace self with the data from other account merging storage cache
+	pub fn merge_with(&mut self, other: Account) {
+		assert!(self.storage_is_clean());
+		assert!(other.storage_is_clean());
+		self.balance = other.balance;
+		self.nonce = other.nonce;
+		self.storage_root = other.storage_root;
+		self.code_hash = other.code_hash;
+		self.code_cache = other.code_cache;
+		self.code_size = other.code_size;
+		self.address_hash = other.address_hash;
+		let mut cache = self.storage_cache.borrow_mut();
+		for (k, v) in other.storage_cache.into_inner().into_iter() {
+			cache.insert(k.clone() , v.clone()); //TODO: cloning should not be required here
+		}
+	}
 }
 
 impl fmt::Debug for Account {
@@ -416,6 +537,7 @@ mod tests {
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
 		a.init_code(vec![0x55, 0x44, 0xffu8]);
 		assert_eq!(a.code_hash(), SHA3_EMPTY);
+		assert_eq!(a.code_size(), Some(3));
 		a.commit_code(&mut db);
 		assert_eq!(a.code_hash().hex(), "af231e631776a517ca23125370d542873eca1fb4d613ed9b5d5335a46ae5b7eb");
 	}

ethcore/src/state/mod.rs

@@ -23,6 +23,7 @@ use trace::FlatTrace;
 use pod_account::*;
 use pod_state::{self, PodState};
 use types::state_diff::StateDiff;
+use state_db::StateDB;
 
 mod account;
 mod substate;
@@ -41,23 +42,92 @@ pub struct ApplyOutcome {
 /// Result type for the execution ("application") of a transaction.
 pub type ApplyResult = Result<ApplyOutcome, Error>;
 
+#[derive(Debug)]
+enum AccountEntry {
+	/// Contains account data.
+	Cached(Account),
+	/// Account has been deleted.
+	Killed,
+	/// Account does not exist.
+	Missing,
+}
+
+impl AccountEntry {
+	fn is_dirty(&self) -> bool {
+		match *self {
+			AccountEntry::Cached(ref a) => a.is_dirty(),
+			AccountEntry::Killed => true,
+			AccountEntry::Missing => false,
+		}
+	}
+
+	/// Clone dirty data into new `AccountEntry`.
+	/// Returns None if clean.
+	fn clone_dirty(&self) -> Option<AccountEntry> {
+		match *self {
+			AccountEntry::Cached(ref acc) if acc.is_dirty() => Some(AccountEntry::Cached(acc.clone_dirty())),
+			AccountEntry::Killed => Some(AccountEntry::Killed),
+			_ => None,
+		}
+	}
+
+	/// Clone account entry data that needs to be saved in the snapshot.
+	/// This includes basic account information and all locally cached storage keys
+	fn clone_for_snapshot(&self) -> AccountEntry {
+		match *self {
+			AccountEntry::Cached(ref acc) => AccountEntry::Cached(acc.clone_all()),
+			AccountEntry::Killed => AccountEntry::Killed,
+			AccountEntry::Missing => AccountEntry::Missing,
+		}
+	}
+}
+
 /// Representation of the entire state of all accounts in the system.
+///
+/// `State` can work together with `StateDB` to share account cache.
+///
+/// Local cache contains changes made locally and changes accumulated
+/// locally from previous commits. Global cache reflects the database
+/// state and never contains any changes.
+///
+/// Account data can be in the following cache states:
+/// * In global but not local - something that was queried from the database,
+/// but never modified
+/// * In local but not global - something that was just added (e.g. new account)
+/// * In both with the same value - something that was changed to a new value,
+/// but changed back to a previous block in the same block (same State instance)
+/// * In both with different values - something that was overwritten with a
+/// new value.
+///
+/// All read-only state queries check local cache/modifications first,
+/// then global state cache. If data is not found in any of the caches
+/// it is loaded from the DB to the local cache.
+///
+/// Upon destruction all the local cache data merged into the global cache.
+/// The merge might be rejected if current state is non-canonical.
 pub struct State {
-	db: Box<JournalDB>,
+	db: StateDB,
 	root: H256,
-	cache: RefCell<HashMap<Address, Option<Account>>>,
+	cache: RefCell<HashMap<Address, AccountEntry>>,
-	snapshots: RefCell<Vec<HashMap<Address, Option<Option<Account>>>>>,
+	snapshots: RefCell<Vec<HashMap<Address, Option<AccountEntry>>>>,
 	account_start_nonce: U256,
 	factories: Factories,
 }
 
+#[derive(Copy, Clone)]
+enum RequireCache {
+	None,
+	CodeSize,
+	Code,
+}
+
 const SEC_TRIE_DB_UNWRAP_STR: &'static str = "A state can only be created with valid root. Creating a SecTrieDB with a valid root will not fail. \
 			 Therefore creating a SecTrieDB with this state's root will not fail.";
 
 impl State {
 	/// Creates new state with empty state root
 	#[cfg(test)]
-	pub fn new(mut db: Box<JournalDB>, account_start_nonce: U256, factories: Factories) -> State {
+	pub fn new(mut db: StateDB, account_start_nonce: U256, factories: Factories) -> State {
 		let mut root = H256::new();
 		{
 			// init trie and reset root too null
@@ -75,7 +145,7 @@ impl State {
 	}
 
 	/// Creates new state with existing state root
-	pub fn from_existing(db: Box<JournalDB>, root: H256, account_start_nonce: U256, factories: Factories) -> Result<State, TrieError> {
+	pub fn from_existing(db: StateDB, root: H256, account_start_nonce: U256, factories: Factories) -> Result<State, TrieError> {
 		if !db.as_hashdb().contains(&root) {
 			return Err(TrieError::InvalidStateRoot(root));
 		}
@@ -119,14 +189,21 @@ impl State {
 						self.cache.borrow_mut().insert(k, v);
 					},
 					None => {
-						self.cache.borrow_mut().remove(&k);
+						match self.cache.borrow_mut().entry(k) {
+							::std::collections::hash_map::Entry::Occupied(e) => {
+								if e.get().is_dirty() {
+									e.remove();
+								}
+							},
+							_ => {}
+						}
 					}
 				}
 			}
 		}
 	}
 
-	fn insert_cache(&self, address: &Address, account: Option<Account>) {
+	fn insert_cache(&self, address: &Address, account: AccountEntry) {
 		if let Some(ref mut snapshot) = self.snapshots.borrow_mut().last_mut() {
 			if !snapshot.contains_key(address) {
 				snapshot.insert(address.clone(), self.cache.borrow_mut().insert(address.clone(), account));
@@ -139,13 +216,14 @@ impl State {
 	fn note_cache(&self, address: &Address) {
 		if let Some(ref mut snapshot) = self.snapshots.borrow_mut().last_mut() {
 			if !snapshot.contains_key(address) {
-				snapshot.insert(address.clone(), self.cache.borrow().get(address).cloned());
+				snapshot.insert(address.clone(), self.cache.borrow().get(address).map(AccountEntry::clone_for_snapshot));
 			}
 		}
 	}
 
 	/// Destroy the current object and return root and database.
-	pub fn drop(self) -> (H256, Box<JournalDB>) {
+	pub fn drop(mut self) -> (H256, StateDB) {
+		self.commit_cache();
 		(self.root, self.db)
 	}
 
@@ -157,50 +235,99 @@ impl State {
 	/// Create a new contract at address `contract`. If there is already an account at the address
 	/// it will have its code reset, ready for `init_code()`.
 	pub fn new_contract(&mut self, contract: &Address, balance: U256) {
-		self.insert_cache(contract, Some(Account::new_contract(balance, self.account_start_nonce)));
+		self.insert_cache(contract, AccountEntry::Cached(Account::new_contract(balance, self.account_start_nonce)));
 	}
 
 	/// Remove an existing account.
 	pub fn kill_account(&mut self, account: &Address) {
-		self.insert_cache(account, None);
+		self.insert_cache(account, AccountEntry::Killed);
 	}
 
 	/// Determine whether an account exists.
 	pub fn exists(&self, a: &Address) -> bool {
-		self.ensure_cached(a, false, |a| a.is_some())
+		self.ensure_cached(a, RequireCache::None, |a| a.is_some())
 	}
 
 	/// Get the balance of account `a`.
 	pub fn balance(&self, a: &Address) -> U256 {
-		self.ensure_cached(a, false,
+		self.ensure_cached(a, RequireCache::None,
 			|a| a.as_ref().map_or(U256::zero(), |account| *account.balance()))
 	}
 
 	/// Get the nonce of account `a`.
 	pub fn nonce(&self, a: &Address) -> U256 {
-		self.ensure_cached(a, false,
+		self.ensure_cached(a, RequireCache::None,
 			|a| a.as_ref().map_or(self.account_start_nonce, |account| *account.nonce()))
 	}
 
 	/// Mutate storage of account `address` so that it is `value` for `key`.
 	pub fn storage_at(&self, address: &Address, key: &H256) -> H256 {
-		self.ensure_cached(address, false, |a| a.as_ref().map_or(H256::new(), |a| {
+		// Storage key search and update works like this:
-			let addr_hash = a.address_hash(address);
+		// 1. If there's an entry for the account in the local cache check for the key and return it if found.
-			let db = self.factories.accountdb.readonly(self.db.as_hashdb(), addr_hash);
+		// 2. If there's an entry for the account in the global cache check for the key or load it into that account.
-			a.storage_at(db.as_hashdb(), key)
+		// 3. If account is missing in the global cache load it into the local cache and cache the key there.
-		}))
+
+		// check local cache first without updating
+		{
+			let local_cache = self.cache.borrow_mut();
+			let mut local_account = None;
+			if let Some(maybe_acc) = local_cache.get(address) {
+				match *maybe_acc {
+					AccountEntry::Cached(ref account) => {
+						if let Some(value) = account.cached_storage_at(key) {
+							return value;
+						} else {
+							local_account = Some(maybe_acc);
+						}
+					},
+					_ => return H256::new(),
+				}
+			}
+			// check the global cache and and cache storage key there if found,
+			// otherwise cache the account localy and cache storage key there.
+			if let Some(result) = self.db.get_cached(address, |acc| acc.map_or(H256::new(), |a| {
+					let account_db = self.factories.accountdb.readonly(self.db.as_hashdb(), a.address_hash(address));
+					a.storage_at(account_db.as_hashdb(), key)
+				})) {
+				return result;
+			}
+			if let Some(ref mut acc) = local_account {
+				if let AccountEntry::Cached(ref account) = **acc {
+					let account_db = self.factories.accountdb.readonly(self.db.as_hashdb(), account.address_hash(address));
+					return account.storage_at(account_db.as_hashdb(), key)
+				} else {
+					return H256::new()
+				}
+			}
+		}
+		
+		// account is not found in the global cache, get from the DB and insert into local
+		let db = self.factories.trie.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
+		let maybe_acc = match db.get(address) {
+			Ok(acc) => acc.map(Account::from_rlp),
+			Err(e) => panic!("Potential DB corruption encountered: {}", e),
+		};
+		let r = maybe_acc.as_ref().map_or(H256::new(), |a| {
+			let account_db = self.factories.accountdb.readonly(self.db.as_hashdb(), a.address_hash(address));
+			a.storage_at(account_db.as_hashdb(), key)
+		});
+		match maybe_acc {
+			Some(account) => self.insert_cache(address, AccountEntry::Cached(account)),
+			None => self.insert_cache(address, AccountEntry::Missing),
+		}
+		r
 	}
 
-	/// Get the code of account `a`.
+	/// Get accounts' code.
 	pub fn code(&self, a: &Address) -> Option<Bytes> {
-		self.ensure_cached(a, true,
+		self.ensure_cached(a, RequireCache::Code,
-			|a| a.as_ref().map_or(None, |a| a.code().map(|x| x.to_vec())))
+			|a| a.as_ref().map_or(None, |a| a.code().map(|x|x.to_vec())))
 	}
 
-	/// Get the code size of account `a`.
+	/// Get accounts' code size.
 	pub fn code_size(&self, a: &Address) -> Option<usize> {
-		self.ensure_cached(a, true,
+		self.ensure_cached(a, RequireCache::CodeSize,
-			|a| a.as_ref().map_or(None, |a| a.code().map(|x| x.len())))
+			|a| a.as_ref().and_then(|a| a.code_size()))
 	}
 
 	/// Add `incr` to the balance of account `a`.
@@ -262,19 +389,19 @@ impl State {
 	/// Commit accounts to SecTrieDBMut. This is similar to cpp-ethereum's dev::eth::commit.
 	/// `accounts` is mutable because we may need to commit the code or storage and record that.
 	#[cfg_attr(feature="dev", allow(match_ref_pats))]
-	pub fn commit_into(
+	fn commit_into(
 		factories: &Factories,
-		db: &mut HashDB,
+		db: &mut StateDB,
 		root: &mut H256,
-		accounts: &mut HashMap<Address, Option<Account>>
+		accounts: &mut HashMap<Address, AccountEntry>
 	) -> Result<(), Error> {
 		// first, commit the sub trees.
 		// TODO: is this necessary or can we dispense with the `ref mut a` for just `a`?
 		for (address, ref mut a) in accounts.iter_mut() {
 			match a {
-				&mut&mut Some(ref mut account) if account.is_dirty() => {
+				&mut&mut AccountEntry::Cached(ref mut account) if account.is_dirty() => {
 					let addr_hash = account.address_hash(address);
-					let mut account_db = factories.accountdb.create(db, addr_hash);
+					let mut account_db = factories.accountdb.create(db.as_hashdb_mut(), addr_hash);
 					account.commit_storage(&factories.trie, account_db.as_hashdb_mut());
 					account.commit_code(account_db.as_hashdb_mut());
 				}
@@ -283,15 +410,18 @@ impl State {
 		}
 
 		{
-			let mut trie = factories.trie.from_existing(db, root).unwrap();
+			let mut trie = factories.trie.from_existing(db.as_hashdb_mut(), root).unwrap();
 			for (address, ref mut a) in accounts.iter_mut() {
 				match **a {
-					Some(ref mut account) if account.is_dirty() => {
+					AccountEntry::Cached(ref mut account) if account.is_dirty() => {
 						account.set_clean();
-						try!(trie.insert(address, &account.rlp()))
+						try!(trie.insert(address, &account.rlp()));
 					},
-					None => try!(trie.remove(address)),
+					AccountEntry::Killed => {
-					_ => (),
+						try!(trie.remove(address));
+						**a = AccountEntry::Missing;
+					},
+					_ => {},
 				}
 			}
 		}
@@ -299,10 +429,27 @@ impl State {
 		Ok(())
 	}
 
+	fn commit_cache(&mut self) {
+		let mut addresses = self.cache.borrow_mut();
+		for (address, a) in addresses.drain() {
+			match a {
+				AccountEntry::Cached(account) => {
+					if !account.is_dirty() {
+						self.db.cache_account(address, Some(account));
+					}
+				},
+				AccountEntry::Missing => {
+					self.db.cache_account(address, None);
+				},
+				_ => {},
+			}
+		}
+	}
+
 	/// Commits our cached account changes into the trie.
 	pub fn commit(&mut self) -> Result<(), Error> {
 		assert!(self.snapshots.borrow().is_empty());
-		Self::commit_into(&self.factories, self.db.as_hashdb_mut(), &mut self.root, &mut *self.cache.borrow_mut())
+		Self::commit_into(&self.factories, &mut self.db, &mut self.root, &mut *self.cache.borrow_mut())
 	}
 
 	/// Clear state cache
@@ -316,7 +463,7 @@ impl State {
 	pub fn populate_from(&mut self, accounts: PodState) {
 		assert!(self.snapshots.borrow().is_empty());
 		for (add, acc) in accounts.drain().into_iter() {
-			self.cache.borrow_mut().insert(add, Some(Account::from_pod(acc)));
+			self.cache.borrow_mut().insert(add, AccountEntry::Cached(Account::from_pod(acc)));
 		}
 	}
 
@@ -326,7 +473,7 @@ impl State {
 		// TODO: handle database rather than just the cache.
 		// will need fat db.
 		PodState::from(self.cache.borrow().iter().fold(BTreeMap::new(), |mut m, (add, opt)| {
-			if let Some(ref acc) = *opt {
+			if let AccountEntry::Cached(ref acc) = *opt {
 				m.insert(add.clone(), PodAccount::from_account(acc));
 			}
 			m
@@ -335,7 +482,7 @@ impl State {
 
 	fn query_pod(&mut self, query: &PodState) {
 		for (address, pod_account) in query.get() {
-			self.ensure_cached(address, true, |a| {
+			self.ensure_cached(address, RequireCache::Code, |a| {
 				if a.is_some() {
 					for key in pod_account.storage.keys() {
 						self.storage_at(address, key);
@@ -354,28 +501,61 @@ impl State {
 		pod_state::diff_pod(&state_pre.to_pod(), &pod_state_post)
 	}
 
-	/// Ensure account `a` is in our cache of the trie DB and return a handle for getting it.
+	fn update_account_cache(require: RequireCache, account: &mut Account, db: &HashDB) {
-	/// `require_code` requires that the code be cached, too.
+		match require {
-	fn ensure_cached<'a, F, U>(&'a self, a: &'a Address, require_code: bool, f: F) -> U
+			RequireCache::None => {},
-		where F: FnOnce(&Option<Account>) -> U {
+			RequireCache::Code => {
-		let have_key = self.cache.borrow().contains_key(a);
+				account.cache_code(db);
-		if !have_key {
+			}
-			let db = self.factories.trie.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
+			RequireCache::CodeSize => {
-			let maybe_acc = match db.get(a) {
+				account.cache_code_size(db);
-				Ok(acc) => acc.map(Account::from_rlp),
-				Err(e) => panic!("Potential DB corruption encountered: {}", e),
-			};
-			self.insert_cache(a, maybe_acc);
-		}
-		if require_code {
-			if let Some(ref mut account) = self.cache.borrow_mut().get_mut(a).unwrap().as_mut() {
-				let addr_hash = account.address_hash(a);
-				let accountdb = self.factories.accountdb.readonly(self.db.as_hashdb(), addr_hash);
-				account.cache_code(accountdb.as_hashdb());
 			}
 		}
+	}
 
-		f(self.cache.borrow().get(a).unwrap())
+	/// Check caches for required data
+	/// First searches for account in the local, then the shared cache.
+	/// Populates local cache if nothing found.
+	fn ensure_cached<F, U>(&self, a: &Address, require: RequireCache, f: F) -> U
+		where F: Fn(Option<&Account>) -> U {
+		// check local cache first
+		if let Some(ref mut maybe_acc) = self.cache.borrow_mut().get_mut(a) {
+			if let AccountEntry::Cached(ref mut account) = **maybe_acc {
+				let accountdb = self.factories.accountdb.readonly(self.db.as_hashdb(), account.address_hash(a));
+				Self::update_account_cache(require, account, accountdb.as_hashdb());
+				return f(Some(account));
+			}
+			return f(None);
+		}
+		// check global cache
+		let result = self.db.get_cached(a, |mut acc| {
+			if let Some(ref mut account) = acc {
+				let accountdb = self.factories.accountdb.readonly(self.db.as_hashdb(), account.address_hash(a));
+				Self::update_account_cache(require, account, accountdb.as_hashdb());
+			}
+			f(acc.map(|a| &*a))
+		});
+		match result {
+			Some(r) => r,
+			None => {
+				// not found in the global cache, get from the DB and insert into local
+				let db = self.factories.trie.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
+				let mut maybe_acc = match db.get(a) {
+					Ok(acc) => acc.map(Account::from_rlp),
+					Err(e) => panic!("Potential DB corruption encountered: {}", e),
+				};
+				if let Some(ref mut account) = maybe_acc.as_mut() {
+					let accountdb = self.factories.accountdb.readonly(self.db.as_hashdb(), account.address_hash(a));
+					Self::update_account_cache(require, account, accountdb.as_hashdb());
+				}
+				let r = f(maybe_acc.as_ref());
+				match maybe_acc {
+					Some(account) => self.insert_cache(a, AccountEntry::Cached(account)),
+					None => self.insert_cache(a, AccountEntry::Missing),
+				}
+				r
+			}
+		}
 	}
 
 	/// Pull account `a` in our cache from the trie DB. `require_code` requires that the code be cached, too.
@@ -390,30 +570,40 @@ impl State {
 	{
 		let contains_key = self.cache.borrow().contains_key(a);
 		if !contains_key {
-			let db = self.factories.trie.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
+			match self.db.get_cached_account(a) {
-			let maybe_acc = match db.get(a) {
+				Some(Some(acc)) => self.insert_cache(a, AccountEntry::Cached(acc)),
-				Ok(acc) => acc.map(Account::from_rlp),
+				Some(None) => self.insert_cache(a, AccountEntry::Missing),
-				Err(e) => panic!("Potential DB corruption encountered: {}", e),
+				None => {
-			};
+					let db = self.factories.trie.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
-
+					let maybe_acc = match db.get(a) {
-			self.insert_cache(a, maybe_acc);
+						Ok(Some(acc)) => AccountEntry::Cached(Account::from_rlp(acc)),
+						Ok(None) => AccountEntry::Missing,
+						Err(e) => panic!("Potential DB corruption encountered: {}", e),
+					};
+					self.insert_cache(a, maybe_acc);
+				}
+			}
 		} else {
 			self.note_cache(a);
 		}
 
 		match self.cache.borrow_mut().get_mut(a).unwrap() {
-			&mut Some(ref mut acc) => not_default(acc),
+			&mut AccountEntry::Cached(ref mut acc) => not_default(acc),
-			slot @ &mut None => *slot = Some(default()),
+			slot => *slot = AccountEntry::Cached(default()),
 		}
 
 		RefMut::map(self.cache.borrow_mut(), |c| {
-			let account = c.get_mut(a).unwrap().as_mut().unwrap();
+			match c.get_mut(a).unwrap() {
-			if require_code {
+				&mut AccountEntry::Cached(ref mut account) => {
-				let addr_hash = account.address_hash(a);
+					if require_code {
-				let accountdb = self.factories.accountdb.readonly(self.db.as_hashdb(), addr_hash);
+						let addr_hash = account.address_hash(a);
-				account.cache_code(accountdb.as_hashdb());
+						let accountdb = self.factories.accountdb.readonly(self.db.as_hashdb(), addr_hash);
+						account.cache_code(accountdb.as_hashdb());
+					}
+					account
+				},
+				_ => panic!("Required account must always exist; qed"),
 			}
-			account
 		})
 	}
 }
@@ -427,17 +617,10 @@ impl fmt::Debug for State {
 impl Clone for State {
 	fn clone(&self) -> State {
 		let cache = {
-			let mut cache = HashMap::new();
+			let mut cache: HashMap<Address, AccountEntry> = HashMap::new();
 			for (key, val) in self.cache.borrow().iter() {
-				let key = key.clone();
+				if let Some(entry) = val.clone_dirty() {
-				match *val {
+					cache.insert(key.clone(), entry);
-					Some(ref acc) if acc.is_dirty() => {
-						cache.insert(key, Some(acc.clone()));
-					},
-					None => {
-						cache.insert(key, None);
-					},
-					_ => {},
 				}
 			}
 			cache
@@ -447,7 +630,7 @@ impl Clone for State {
 			db: self.db.boxed_clone(),
 			root: self.root.clone(),
 			cache: RefCell::new(cache),
-			snapshots: RefCell::new(self.snapshots.borrow().clone()),
+			snapshots: RefCell::new(Vec::new()),
 			account_start_nonce: self.account_start_nonce.clone(),
 			factories: self.factories.clone(),
 		}

ethcore/src/state_db.rs

@@ -0,0 +1,161 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+use lru_cache::LruCache;
+use util::journaldb::JournalDB;
+use util::hash::{H256};
+use util::hashdb::HashDB;
+use util::{Arc, Address, DBTransaction, UtilError, Mutex};
+use state::Account;
+
+const STATE_CACHE_ITEMS: usize = 65536;
+
+struct AccountCache {
+	/// DB Account cache. `None` indicates that account is known to be missing.
+	accounts: LruCache<Address, Option<Account>>,
+}
+
+/// State database abstraction.
+/// Manages shared global state cache.
+/// A clone of `StateDB` may be created as canonical or not.
+/// For canonical clones cache changes are accumulated and applied
+/// on commit.
+/// For non-canonical clones cache is cleared on commit.
+pub struct StateDB {
+	db: Box<JournalDB>,
+	account_cache: Arc<Mutex<AccountCache>>,
+	cache_overlay: Vec<(Address, Option<Account>)>,
+	is_canon: bool,
+}
+
+impl StateDB {
+	/// Create a new instance wrapping `JournalDB`
+	pub fn new(db: Box<JournalDB>) -> StateDB {
+		StateDB {
+			db: db,
+			account_cache: Arc::new(Mutex::new(AccountCache { accounts: LruCache::new(STATE_CACHE_ITEMS) })),
+			cache_overlay: Vec::new(),
+			is_canon: false,
+		}
+	}
+
+	/// Commit all recent insert operations and canonical historical commits' removals from the
+	/// old era to the backing database, reverting any non-canonical historical commit's inserts.
+	pub fn commit(&mut self, batch: &mut DBTransaction, now: u64, id: &H256, end: Option<(u64, H256)>) -> Result<u32, UtilError> {
+		let records = try!(self.db.commit(batch, now, id, end));
+		if self.is_canon {
+			self.commit_cache();
+		} else {
+			self.clear_cache();
+		}
+		Ok(records)
+	}
+
+	/// Returns an interface to HashDB.
+	pub fn as_hashdb(&self) -> &HashDB {
+		self.db.as_hashdb()
+	}
+
+	/// Returns an interface to mutable HashDB.
+	pub fn as_hashdb_mut(&mut self) -> &mut HashDB {
+		self.db.as_hashdb_mut()
+	}
+
+	/// Clone the database.
+	pub fn boxed_clone(&self) -> StateDB {
+		StateDB {
+			db: self.db.boxed_clone(),
+			account_cache: self.account_cache.clone(),
+			cache_overlay: Vec::new(),
+			is_canon: false,
+		}
+	}
+
+	/// Clone the database for a canonical state.
+	pub fn boxed_clone_canon(&self) -> StateDB {
+		StateDB {
+			db: self.db.boxed_clone(),
+			account_cache: self.account_cache.clone(),
+			cache_overlay: Vec::new(),
+			is_canon: true,
+		}
+	}
+
+	/// Check if pruning is enabled on the database.
+	pub fn is_pruned(&self) -> bool {
+		self.db.is_pruned()
+	}
+
+	/// Heap size used.
+	pub fn mem_used(&self) -> usize {
+		self.db.mem_used() //TODO: + self.account_cache.lock().heap_size_of_children()
+	}
+
+	/// Returns underlying `JournalDB`.
+	pub fn journal_db(&self) -> &JournalDB {
+		&*self.db
+	}
+
+	/// Enqueue cache change.
+	pub fn cache_account(&mut self, addr: Address, data: Option<Account>) {
+		self.cache_overlay.push((addr, data));
+	}
+
+	/// Apply pending cache changes.
+	fn commit_cache(&mut self) {
+		let mut cache = self.account_cache.lock();
+		for (address, account) in self.cache_overlay.drain(..) {
+			if let Some(&mut Some(ref mut existing)) = cache.accounts.get_mut(&address) {
+				if let Some(new) = account {
+					existing.merge_with(new);
+					continue;
+				}
+			}
+			cache.accounts.insert(address, account);
+		}
+	}
+
+	/// Clear the cache.
+	pub fn clear_cache(&mut self) {
+		self.cache_overlay.clear();
+		let mut cache = self.account_cache.lock();
+		cache.accounts.clear();
+	}
+
+	/// Get basic copy of the cached account. Does not include storage.
+	/// Returns 'None' if the state is non-canonical and cache is disabled
+	/// or if the account is not cached.
+	pub fn get_cached_account(&self, addr: &Address) -> Option<Option<Account>> {
+		if !self.is_canon {
+			return None;
+		}
+		let mut cache = self.account_cache.lock();
+		cache.accounts.get_mut(&addr).map(|a| a.as_ref().map(|a| a.clone_basic()))
+	}
+
+	/// Get value from a cached account.
+	/// Returns 'None' if the state is non-canonical and cache is disabled
+	/// or if the account is not cached.
+	pub fn get_cached<F, U>(&self, a: &Address, f: F) -> Option<U>
+		where F: FnOnce(Option<&mut Account>) -> U {
+		if !self.is_canon {
+			return None;
+		}
+		let mut cache = self.account_cache.lock();
+		cache.accounts.get_mut(a).map(|c| f(c.as_mut()))
+	}
+}
+

ethcore/src/tests/helpers.rs

@@ -19,6 +19,7 @@ use io::*;
 use client::{BlockChainClient, Client, ClientConfig};
 use common::*;
 use spec::*;
+use state_db::StateDB;
 use block::{OpenBlock, Drain};
 use blockchain::{BlockChain, Config as BlockChainConfig};
 use state::*;
@@ -146,9 +147,9 @@ pub fn generate_dummy_client_with_spec_and_data<F>(get_test_spec: F, block_numbe
 	).unwrap();
 	let test_engine = &*test_spec.engine;
 
-	let mut db_result = get_temp_journal_db();
+	let mut db_result = get_temp_state_db();
 	let mut db = db_result.take();
-	test_spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+	test_spec.ensure_db_good(&mut db).unwrap();
 	let genesis_header = test_spec.genesis_header();
 
 	let mut rolling_timestamp = 40;
@@ -321,9 +322,9 @@ pub fn generate_dummy_empty_blockchain() -> GuardedTempResult<BlockChain> {
 	}
 }
 
-pub fn get_temp_journal_db() -> GuardedTempResult<Box<JournalDB>> {
+pub fn get_temp_state_db() -> GuardedTempResult<StateDB> {
 	let temp = RandomTempPath::new();
-	let journal_db = get_temp_journal_db_in(temp.as_path());
+	let journal_db = get_temp_state_db_in(temp.as_path());
 
 	GuardedTempResult {
 		_temp: temp,
@@ -333,7 +334,7 @@ pub fn get_temp_journal_db() -> GuardedTempResult<Box<JournalDB>> {
 
 pub fn get_temp_state() -> GuardedTempResult<State> {
 	let temp = RandomTempPath::new();
-	let journal_db = get_temp_journal_db_in(temp.as_path());
+	let journal_db = get_temp_state_db_in(temp.as_path());
 
 	GuardedTempResult {
 	    _temp: temp,
@@ -341,13 +342,14 @@ pub fn get_temp_state() -> GuardedTempResult<State> {
 	}
 }
 
-pub fn get_temp_journal_db_in(path: &Path) -> Box<JournalDB> {
+pub fn get_temp_state_db_in(path: &Path) -> StateDB {
 	let db = new_db(path.to_str().expect("Only valid utf8 paths for tests."));
-	journaldb::new(db.clone(), journaldb::Algorithm::EarlyMerge, None)
+	let journal_db = journaldb::new(db.clone(), journaldb::Algorithm::EarlyMerge, None);
+	StateDB::new(journal_db)
 }
 
 pub fn get_temp_state_in(path: &Path) -> State {
-	let journal_db = get_temp_journal_db_in(path);
+	let journal_db = get_temp_state_db_in(path);
 	State::new(journal_db, U256::from(0), Default::default())
 }
 

ethcore/src/trace/executive_tracer.rs

@@ -31,7 +31,7 @@ fn top_level_subtraces(traces: &[FlatTrace]) -> usize {
 	traces.iter().filter(|t| t.trace_address.is_empty()).count()
 }
 
-fn update_trace_address(traces: Vec<FlatTrace>) -> Vec<FlatTrace> {
+fn prefix_subtrace_addresses(mut traces: Vec<FlatTrace>) -> Vec<FlatTrace> {
 	// input traces are expected to be ordered like
 	// []
 	// [0]
@@ -48,24 +48,36 @@ fn update_trace_address(traces: Vec<FlatTrace>) -> Vec<FlatTrace> {
 	// [0, 0, 1]
 	// [1]
 	// [1, 0]
-	let mut top_subtrace_index = 0;
+	let mut current_subtrace_index = 0;
-	let mut subtrace_subtraces_left = 0;
+	let mut first = true;
-	traces.into_iter().map(|mut trace| {
+	for trace in traces.iter_mut() {
-		let is_top_subtrace = trace.trace_address.is_empty();
+		match (first, trace.trace_address.is_empty()) {
-		let is_subtrace = trace.trace_address.len() == 1;
+			(true, _) => first = false,
-		trace.trace_address.push_front(top_subtrace_index);
+			(_, true) => current_subtrace_index += 1,
-
+			_ => {}
-		if is_top_subtrace {
-			subtrace_subtraces_left = trace.subtraces;
-		} else if is_subtrace {
-			subtrace_subtraces_left -= 1;
 		}			
+		trace.trace_address.push_front(current_subtrace_index);
+	}
+	traces
+}
 
-		if subtrace_subtraces_left == 0 {
+#[test]
-			top_subtrace_index += 1;
+fn should_prefix_address_properly() {
-		}
+	use super::trace::{Action, Res, Suicide};
-		trace
+
-	}).collect()
+	let f = |v: Vec<usize>| FlatTrace {
+		action: Action::Suicide(Suicide {
+			address: Default::default(),
+			balance: Default::default(),
+			refund_address: Default::default(),
+		}),
+		result: Res::None,
+		subtraces: 0,
+		trace_address: v.into_iter().collect(),
+	};
+	let t = vec![vec![], vec![0], vec![0, 0], vec![0], vec![], vec![], vec![0], vec![]].into_iter().map(&f).collect();
+	let t = prefix_subtrace_addresses(t);
+	assert_eq!(t, vec![vec![0], vec![0, 0], vec![0, 0, 0], vec![0, 0], vec![1], vec![2], vec![2, 0], vec![3]].into_iter().map(&f).collect::<Vec<_>>());
 }  
 
 impl Tracer for ExecutiveTracer {
@@ -93,7 +105,7 @@ impl Tracer for ExecutiveTracer {
 		};
 		debug!(target: "trace", "Traced call {:?}", trace);
 		self.traces.push(trace);
-		self.traces.extend(update_trace_address(subs));
+		self.traces.extend(prefix_subtrace_addresses(subs));
 	}
 
 	fn trace_create(&mut self, create: Option<Create>, gas_used: U256, code: Option<Bytes>, address: Address, subs: Vec<FlatTrace>) {
@@ -109,7 +121,7 @@ impl Tracer for ExecutiveTracer {
 		};
 		debug!(target: "trace", "Traced create {:?}", trace);
 		self.traces.push(trace);
-		self.traces.extend(update_trace_address(subs));
+		self.traces.extend(prefix_subtrace_addresses(subs));
 	}
 
 	fn trace_failed_call(&mut self, call: Option<Call>, subs: Vec<FlatTrace>, error: TraceError) {
@@ -121,7 +133,7 @@ impl Tracer for ExecutiveTracer {
 		};
 		debug!(target: "trace", "Traced failed call {:?}", trace);
 		self.traces.push(trace);
-		self.traces.extend(update_trace_address(subs));
+		self.traces.extend(prefix_subtrace_addresses(subs));
 	}
 
 	fn trace_failed_create(&mut self, create: Option<Create>, subs: Vec<FlatTrace>, error: TraceError) {
@@ -133,7 +145,7 @@ impl Tracer for ExecutiveTracer {
 		};
 		debug!(target: "trace", "Traced failed create {:?}", trace);
 		self.traces.push(trace);
-		self.traces.extend(update_trace_address(subs));
+		self.traces.extend(prefix_subtrace_addresses(subs));
 	}
 
 	fn trace_suicide(&mut self, address: Address, balance: U256, refund_address: Address) {

ethcore/src/types/block_status.rs

@@ -15,6 +15,7 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
 //! Block status description module
+use verification::queue::Status as QueueStatus;
 
 /// General block status
 #[derive(Debug, Eq, PartialEq, Binary)]
@@ -28,3 +29,13 @@ pub enum BlockStatus {
 	/// Unknown.
 	Unknown,
 }
+
+impl From<QueueStatus> for BlockStatus {
+	fn from(status: QueueStatus) -> Self {
+		match status {
+			QueueStatus::Queued => BlockStatus::Queued,
+			QueueStatus::Bad => BlockStatus::Bad,
+			QueueStatus::Unknown => BlockStatus::Unknown,
+		}
+	}
+}

ethcore/src/types/mod.rs.in

@@ -25,7 +25,7 @@ pub mod executed;
 pub mod block_status;
 pub mod account_diff;
 pub mod state_diff;
-pub mod block_queue_info;
+pub mod verification_queue_info;
 pub mod filter;
 pub mod trace_filter;
 pub mod call_analytics;

ethcore/src/types/transaction.rs

@@ -20,7 +20,7 @@ use std::ops::Deref;
 use std::cell::*;
 use rlp::*;
 use util::sha3::Hashable;
-use util::{H256, Address, U256, Bytes};
+use util::{H256, Address, U256, Bytes, HeapSizeOf};
 use ethkey::{Signature, sign, Secret, Public, recover, public_to_address, Error as EthkeyError};
 use error::*;
 use evm::Schedule;
@@ -86,6 +86,12 @@ impl Transaction {
 	}
 }
 
+impl HeapSizeOf for Transaction {
+	fn heap_size_of_children(&self) -> usize {
+		self.data.heap_size_of_children()
+	}
+}
+
 impl From<ethjson::state::Transaction> for SignedTransaction {
 	fn from(t: ethjson::state::Transaction) -> Self {
 		let to: Option<ethjson::hash::Address> = t.to.into();
@@ -251,6 +257,12 @@ impl Encodable for SignedTransaction {
 	fn rlp_append(&self, s: &mut RlpStream) { self.rlp_append_sealed_transaction(s) }
 }
 
+impl HeapSizeOf for SignedTransaction {
+	fn heap_size_of_children(&self) -> usize {
+		self.unsigned.heap_size_of_children()
+	}
+}
+
 impl SignedTransaction {
 	/// Append object with a signature into RLP stream
 	pub fn rlp_append_sealed_transaction(&self, s: &mut RlpStream) {

ethcore/src/types/verification_queue_info.rs

@@ -0,0 +1,53 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Verification queue info types
+
+/// Verification queue status
+#[derive(Debug, Binary)]
+pub struct VerificationQueueInfo {
+	/// Number of queued items pending verification
+	pub unverified_queue_size: usize,
+	/// Number of verified queued items pending import
+	pub verified_queue_size: usize,
+	/// Number of items being verified
+	pub verifying_queue_size: usize,
+	/// Configured maximum number of items in the queue
+	pub max_queue_size: usize,
+	/// Configured maximum number of bytes to use
+	pub max_mem_use: usize,
+	/// Heap memory used in bytes
+	pub mem_used: usize,
+}
+
+impl VerificationQueueInfo {
+	/// The total size of the queues.
+	pub fn total_queue_size(&self) -> usize { self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size }
+
+	/// The size of the unverified and verifying queues.
+	pub fn incomplete_queue_size(&self) -> usize { self.unverified_queue_size + self.verifying_queue_size }
+
+	/// Indicates that queue is full
+	pub fn is_full(&self) -> bool {
+		self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size > self.max_queue_size ||
+			self.mem_used > self.max_mem_use
+	}
+
+	/// Indicates that queue is empty
+	pub fn is_empty(&self) -> bool {
+		self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size == 0
+	}
+}

ethcore/src/verification/mod.rs

@@ -16,6 +16,7 @@
 
 pub mod verification;
 pub mod verifier;
+pub mod queue;
 mod canon_verifier;
 mod noop_verifier;
 
@@ -23,6 +24,7 @@ pub use self::verification::*;
 pub use self::verifier::Verifier;
 pub use self::canon_verifier::CanonVerifier;
 pub use self::noop_verifier::NoopVerifier;
+pub use self::queue::{BlockQueue, Config as QueueConfig, VerificationQueue, QueueInfo};
 
 /// Verifier type.
 #[derive(Debug, PartialEq, Clone)]

ethcore/src/verification/queue/kind.rs

@@ -0,0 +1,182 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Definition of valid items for the verification queue.
+
+use engines::Engine;
+use error::Error;
+
+use util::{HeapSizeOf, H256};
+
+pub use self::blocks::Blocks;
+pub use self::headers::Headers;
+
+/// Something which can produce a hash and a parent hash.
+pub trait HasHash {
+	/// Get the hash of this item.
+	fn hash(&self) -> H256;
+
+	/// Get the hash of this item's parent.
+	fn parent_hash(&self) -> H256;
+}
+
+/// Defines transitions between stages of verification.
+///
+/// It starts with a fallible transformation from an "input" into the unverified item.
+/// This consists of quick, simply done checks as well as extracting particular data.
+///
+/// Then, there is a `verify` function which performs more expensive checks and
+/// produces the verified output.
+///
+/// For correctness, the hashes produced by each stage of the pipeline should be
+/// consistent.
+pub trait Kind: 'static + Sized + Send + Sync {
+	/// The first stage: completely unverified.
+	type Input: Sized + Send + HasHash + HeapSizeOf;
+
+	/// The second stage: partially verified.
+	type Unverified: Sized + Send + HasHash + HeapSizeOf;
+
+	/// The third stage: completely verified.
+	type Verified: Sized + Send + HasHash + HeapSizeOf;
+
+	/// Attempt to create the `Unverified` item from the input.
+	fn create(input: Self::Input, engine: &Engine) -> Result<Self::Unverified, Error>;
+
+	/// Attempt to verify the `Unverified` item using the given engine.
+	fn verify(unverified: Self::Unverified, engine: &Engine) -> Result<Self::Verified, Error>;
+}
+
+/// The blocks verification module.
+pub mod blocks {
+	use super::{Kind, HasHash};
+
+	use engines::Engine;
+	use error::Error;
+	use header::Header;
+	use verification::{PreverifiedBlock, verify_block_basic, verify_block_unordered};
+
+	use util::{Bytes, HeapSizeOf, H256};
+
+	/// A mode for verifying blocks.
+	pub struct Blocks;
+
+	impl Kind for Blocks {
+		type Input = Unverified;
+		type Unverified = Unverified;
+		type Verified = PreverifiedBlock;
+
+		fn create(input: Self::Input, engine: &Engine) -> Result<Self::Unverified, Error> {
+			match verify_block_basic(&input.header, &input.bytes, engine) {
+				Ok(()) => Ok(input),
+				Err(e) => {
+					warn!(target: "client", "Stage 1 block verification failed for {}: {:?}", input.hash(), e);
+					Err(e)
+				}
+			}
+		}
+
+		fn verify(un: Self::Unverified, engine: &Engine) -> Result<Self::Verified, Error> {
+			let hash = un.hash();
+			match verify_block_unordered(un.header, un.bytes, engine) {
+				Ok(verified) => Ok(verified),
+				Err(e) => {
+					warn!(target: "client", "Stage 2 block verification failed for {}: {:?}", hash, e);
+					Err(e)
+				}
+			}
+		}
+	}
+
+	/// An unverified block.
+	pub struct Unverified {
+		header: Header,
+		bytes: Bytes,
+	}
+
+	impl Unverified {
+		/// Create an `Unverified` from raw bytes.
+		pub fn new(bytes: Bytes) -> Self {
+			use views::BlockView;
+
+			let header = BlockView::new(&bytes).header();
+			Unverified {
+				header: header,
+				bytes: bytes,
+			}
+		}
+	}
+
+	impl HeapSizeOf for Unverified {
+		fn heap_size_of_children(&self) -> usize {
+			self.header.heap_size_of_children() + self.bytes.heap_size_of_children()
+		}
+	}
+
+	impl HasHash for Unverified {
+		fn hash(&self) -> H256 {
+			self.header.hash()
+		}
+
+		fn parent_hash(&self) -> H256 {
+			self.header.parent_hash().clone()
+		}
+	}
+
+	impl HasHash for PreverifiedBlock {
+		fn hash(&self) -> H256 {
+			self.header.hash()
+		}
+
+		fn parent_hash(&self) -> H256 {
+			self.header.parent_hash().clone()
+		}
+	}
+}
+
+/// Verification for headers.
+pub mod headers {
+	use super::{Kind, HasHash};
+
+	use engines::Engine;
+	use error::Error;
+	use header::Header;
+	use verification::verify_header_params;
+
+	use util::hash::H256;
+
+	impl HasHash for Header {
+		fn hash(&self) -> H256 { self.hash() }
+		fn parent_hash(&self) -> H256 { self.parent_hash().clone() }
+	}
+
+	/// A mode for verifying headers.
+	pub struct Headers;
+
+	impl Kind for Headers {
+		type Input = Header;
+		type Unverified = Header;
+		type Verified = Header;
+
+		fn create(input: Self::Input, engine: &Engine) -> Result<Self::Unverified, Error> {
+			verify_header_params(&input, engine).map(|_| input)
+		}
+
+		fn verify(unverified: Self::Unverified, engine: &Engine) -> Result<Self::Verified, Error> {
+			engine.verify_block_unordered(&unverified, None).map(|_| unverified)
+		}
+	}
+}

ethcore/src/verification/queue/mod.rs

@@ -16,30 +16,35 @@
 
 //! A queue of blocks. Sits between network or other I/O and the `BlockChain`.
 //! Sorts them ready for blockchain insertion.
+
 use std::thread::{JoinHandle, self};
 use std::sync::atomic::{AtomicBool, Ordering as AtomicOrdering};
 use std::sync::{Condvar as SCondvar, Mutex as SMutex};
 use util::*;
 use io::*;
-use verification::*;
 use error::*;
 use engines::Engine;
-use views::*;
-use header::*;
 use service::*;
-use client::BlockStatus;
 
-pub use types::block_queue_info::BlockQueueInfo;
+use self::kind::{HasHash, Kind};
 
-known_heap_size!(0, UnverifiedBlock, VerifyingBlock, PreverifiedBlock);
+pub use types::verification_queue_info::VerificationQueueInfo as QueueInfo;
+
+pub mod kind;
 
 const MIN_MEM_LIMIT: usize = 16384;
 const MIN_QUEUE_LIMIT: usize = 512;
 
-/// Block queue configuration
+/// Type alias for block queue convenience.
+pub type BlockQueue = VerificationQueue<self::kind::Blocks>;
+
+/// Type alias for header queue convenience.
+pub type HeaderQueue = VerificationQueue<self::kind::Headers>;
+
+/// Verification queue configuration
 #[derive(Debug, PartialEq, Clone)]
-pub struct BlockQueueConfig {
+pub struct Config {
-	/// Maximum number of blocks to keep in unverified queue.
+	/// Maximum number of items to keep in unverified queue.
 	/// When the limit is reached, is_full returns true.
 	pub max_queue_size: usize,
 	/// Maximum heap memory to use.
@@ -47,42 +52,44 @@ pub struct BlockQueueConfig {
 	pub max_mem_use: usize,
 }
 
-impl Default for BlockQueueConfig {
+impl Default for Config {
 	fn default() -> Self {
-		BlockQueueConfig {
+		Config {
 			max_queue_size: 30000,
 			max_mem_use: 50 * 1024 * 1024,
 		}
 	}
 }
 
+/// An item which is in the process of being verified.
+pub struct Verifying<K: Kind> {
+	hash: H256,
+	output: Option<K::Verified>,
+}
 
-impl BlockQueueInfo {
+impl<K: Kind> HeapSizeOf for Verifying<K> {
-	/// The total size of the queues.
+	fn heap_size_of_children(&self) -> usize {
-	pub fn total_queue_size(&self) -> usize { self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size }
+		self.output.heap_size_of_children()
-
-	/// The size of the unverified and verifying queues.
-	pub fn incomplete_queue_size(&self) -> usize { self.unverified_queue_size + self.verifying_queue_size }
-
-	/// Indicates that queue is full
-	pub fn is_full(&self) -> bool {
-		self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size > self.max_queue_size ||
-			self.mem_used > self.max_mem_use
-	}
-
-	/// Indicates that queue is empty
-	pub fn is_empty(&self) -> bool {
-		self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size == 0
 	}
 }
 
-/// A queue of blocks. Sits between network or other I/O and the `BlockChain`.
+/// Status of items in the queue.
-/// Sorts them ready for blockchain insertion.
+pub enum Status {
-pub struct BlockQueue {
+	/// Currently queued.
+	Queued,
+	/// Known to be bad.
+	Bad,
+	/// Unknown.
+	Unknown,
+}
+
+/// A queue of items to be verified. Sits between network or other I/O and the `BlockChain`.
+/// Keeps them in the same order as inserted, minus invalid items.
+pub struct VerificationQueue<K: Kind> {
 	panic_handler: Arc<PanicHandler>,
 	engine: Arc<Engine>,
 	more_to_verify: Arc<SCondvar>,
-	verification: Arc<Verification>,
+	verification: Arc<Verification<K>>,
 	verifiers: Vec<JoinHandle<()>>,
 	deleting: Arc<AtomicBool>,
 	ready_signal: Arc<QueueSignal>,
@@ -92,16 +99,6 @@ pub struct BlockQueue {
 	max_mem_use: usize,
 }
 
-struct UnverifiedBlock {
-	header: Header,
-	bytes: Bytes,
-}
-
-struct VerifyingBlock {
-	hash: H256,
-	block: Option<PreverifiedBlock>,
-}
-
 struct QueueSignal {
 	deleting: Arc<AtomicBool>,
 	signalled: AtomicBool,
@@ -128,19 +125,19 @@ impl QueueSignal {
 	}
 }
 
-struct Verification {
+struct Verification<K: Kind> {
 	// All locks must be captured in the order declared here.
-	unverified: Mutex<VecDeque<UnverifiedBlock>>,
+	unverified: Mutex<VecDeque<K::Unverified>>,
-	verified: Mutex<VecDeque<PreverifiedBlock>>,
+	verified: Mutex<VecDeque<K::Verified>>,
-	verifying: Mutex<VecDeque<VerifyingBlock>>,
+	verifying: Mutex<VecDeque<Verifying<K>>>,
 	bad: Mutex<HashSet<H256>>,
 	more_to_verify: SMutex<()>,
 	empty: SMutex<()>,
 }
 
-impl BlockQueue {
+impl<K: Kind> VerificationQueue<K> {
 	/// Creates a new queue instance.
-	pub fn new(config: BlockQueueConfig, engine: Arc<Engine>, message_channel: IoChannel<ClientIoMessage>) -> BlockQueue {
+	pub fn new(config: Config, engine: Arc<Engine>, message_channel: IoChannel<ClientIoMessage>) -> Self {
 		let verification = Arc::new(Verification {
 			unverified: Mutex::new(VecDeque::new()),
 			verified: Mutex::new(VecDeque::new()),
@@ -175,13 +172,13 @@ impl BlockQueue {
 				.name(format!("Verifier #{}", i))
 				.spawn(move || {
 					panic_handler.catch_panic(move || {
-						BlockQueue::verify(verification, engine, more_to_verify, ready_signal, deleting, empty)
+						VerificationQueue::verify(verification, engine, more_to_verify, ready_signal, deleting, empty)
 					}).unwrap()
 				})
 				.expect("Error starting block verification thread")
 			);
 		}
-		BlockQueue {
+		VerificationQueue {
 			engine: engine,
 			panic_handler: panic_handler,
 			ready_signal: ready_signal.clone(),
@@ -196,7 +193,7 @@ impl BlockQueue {
 		}
 	}
 
-	fn verify(verification: Arc<Verification>, engine: Arc<Engine>, wait: Arc<SCondvar>, ready: Arc<QueueSignal>, deleting: Arc<AtomicBool>, empty: Arc<SCondvar>) {
+	fn verify(verification: Arc<Verification<K>>, engine: Arc<Engine>, wait: Arc<SCondvar>, ready: Arc<QueueSignal>, deleting: Arc<AtomicBool>, empty: Arc<SCondvar>) {
 		while !deleting.load(AtomicOrdering::Acquire) {
 			{
 				let mut more_to_verify = verification.more_to_verify.lock().unwrap();
@@ -214,57 +211,66 @@ impl BlockQueue {
 				}
 			}
 
-			let block = {
+			let item = {
+				// acquire these locks before getting the item to verify.
 				let mut unverified = verification.unverified.lock();
-				if unverified.is_empty() {
-					continue;
-				}
 				let mut verifying = verification.verifying.lock();
-				let block = unverified.pop_front().unwrap();
+
-				verifying.push_back(VerifyingBlock{ hash: block.header.hash(), block: None });
+				let item = match unverified.pop_front() {
-				block
+					Some(item) => item,
+					None => continue,
+				};
+
+				verifying.push_back(Verifying { hash: item.hash(), output: None });
+				item
 			};
 
-			let block_hash = block.header.hash();
+			let hash = item.hash();
-			match verify_block_unordered(block.header, block.bytes, &*engine) {
+			match K::verify(item, &*engine) {
 				Ok(verified) => {
 					let mut verifying = verification.verifying.lock();
-					for e in verifying.iter_mut() {
+					let mut idx = None;
-						if e.hash == block_hash {
+					for (i, e) in verifying.iter_mut().enumerate() {
-							e.block = Some(verified);
+						if e.hash == hash {
+							idx = Some(i);
+							e.output = Some(verified);
 							break;
 						}
 					}
-					if !verifying.is_empty() && verifying.front().unwrap().hash == block_hash {
+
+					if idx == Some(0) {
 						// we're next!
 						let mut verified = verification.verified.lock();
 						let mut bad = verification.bad.lock();
-						BlockQueue::drain_verifying(&mut verifying, &mut verified, &mut bad);
+						VerificationQueue::drain_verifying(&mut verifying, &mut verified, &mut bad);
 						ready.set();
 					}
 				},
-				Err(err) => {
+				Err(_) => {
 					let mut verifying = verification.verifying.lock();
 					let mut verified = verification.verified.lock();
 					let mut bad = verification.bad.lock();
-					warn!(target: "client", "Stage 2 block verification failed for {}\nError: {:?}", block_hash, err);
+
-					bad.insert(block_hash.clone());
+					bad.insert(hash.clone());
-					verifying.retain(|e| e.hash != block_hash);
+					verifying.retain(|e| e.hash != hash);
-					BlockQueue::drain_verifying(&mut verifying, &mut verified, &mut bad);
+
-					ready.set();
+					if verifying.front().map_or(false, |x| x.output.is_some()) {
+						VerificationQueue::drain_verifying(&mut verifying, &mut verified, &mut bad);
+						ready.set();
+					}
 				}
 			}
 		}
 	}
 
-	fn drain_verifying(verifying: &mut VecDeque<VerifyingBlock>, verified: &mut VecDeque<PreverifiedBlock>, bad: &mut HashSet<H256>) {
+	fn drain_verifying(verifying: &mut VecDeque<Verifying<K>>, verified: &mut VecDeque<K::Verified>, bad: &mut HashSet<H256>) {
-		while !verifying.is_empty() && verifying.front().unwrap().block.is_some() {
+		while let Some(output) = verifying.front_mut().and_then(|x| x.output.take()) {
-			let block = verifying.pop_front().unwrap().block.unwrap();
+			assert!(verifying.pop_front().is_some());
-			if bad.contains(block.header.parent_hash()) {
+
-				bad.insert(block.header.hash());
+			if bad.contains(&output.parent_hash()) {
-			}
+				bad.insert(output.hash());
-			else {
+			} else {
-				verified.push_back(block);
+				verified.push_back(output);
 			}
 		}
 	}
@@ -288,21 +294,20 @@ impl BlockQueue {
 		}
 	}
 
-	/// Check if the block is currently in the queue
+	/// Check if the item is currently in the queue
-	pub fn block_status(&self, hash: &H256) -> BlockStatus {
+	pub fn status(&self, hash: &H256) -> Status {
 		if self.processing.read().contains(hash) {
-			return BlockStatus::Queued;
+			return Status::Queued;
 		}
 		if self.verification.bad.lock().contains(hash) {
-			return BlockStatus::Bad;
+			return Status::Bad;
 		}
-		BlockStatus::Unknown
+		Status::Unknown
 	}
 
 	/// Add a block to the queue.
-	pub fn import_block(&self, bytes: Bytes) -> ImportResult {
+	pub fn import(&self, input: K::Input) -> ImportResult {
-		let header = BlockView::new(&bytes).header();
+		let h = input.hash();
-		let h = header.hash();
 		{
 			if self.processing.read().contains(&h) {
 				return Err(ImportError::AlreadyQueued.into());
@@ -313,74 +318,71 @@ impl BlockQueue {
 				return Err(ImportError::KnownBad.into());
 			}
 
-			if bad.contains(header.parent_hash()) {
+			if bad.contains(&input.parent_hash()) {
 				bad.insert(h.clone());
 				return Err(ImportError::KnownBad.into());
 			}
 		}
 
-		match verify_block_basic(&header, &bytes, &*self.engine) {
+		match K::create(input, &*self.engine) {
-			Ok(()) => {
+			Ok(item) => {
 				self.processing.write().insert(h.clone());
-				self.verification.unverified.lock().push_back(UnverifiedBlock { header: header, bytes: bytes });
+				self.verification.unverified.lock().push_back(item);
 				self.more_to_verify.notify_all();
 				Ok(h)
 			},
 			Err(err) => {
-				warn!(target: "client", "Stage 1 block verification failed for {}\nError: {:?}", BlockView::new(&bytes).header_view().sha3(), err);
 				self.verification.bad.lock().insert(h.clone());
 				Err(err)
 			}
 		}
 	}
 
-	/// Mark given block and all its children as bad. Stops verification.
+	/// Mark given item and all its children as bad. pauses verification
-	pub fn mark_as_bad(&self, block_hashes: &[H256]) {
+	/// until complete.
-		if block_hashes.is_empty() {
+	pub fn mark_as_bad(&self, hashes: &[H256]) {
+		if hashes.is_empty() {
 			return;
 		}
 		let mut verified_lock = self.verification.verified.lock();
 		let mut verified = &mut *verified_lock;
 		let mut bad = self.verification.bad.lock();
 		let mut processing = self.processing.write();
-		bad.reserve(block_hashes.len());
+		bad.reserve(hashes.len());
-		for hash in block_hashes {
+		for hash in hashes {
 			bad.insert(hash.clone());
 			processing.remove(hash);
 		}
 
 		let mut new_verified = VecDeque::new();
-		for block in verified.drain(..) {
+		for output in verified.drain(..) {
-			if bad.contains(block.header.parent_hash()) {
+			if bad.contains(&output.parent_hash()) {
-				bad.insert(block.header.hash());
+				bad.insert(output.hash());
-				processing.remove(&block.header.hash());
+				processing.remove(&output.hash());
 			} else {
-				new_verified.push_back(block);
+				new_verified.push_back(output);
 			}
 		}
 		*verified = new_verified;
 	}
 
-	/// Mark given block as processed
+	/// Mark given item as processed
-	pub fn mark_as_good(&self, block_hashes: &[H256]) {
+	pub fn mark_as_good(&self, hashes: &[H256]) {
-		if block_hashes.is_empty() {
+		if hashes.is_empty() {
 			return;
 		}
 		let mut processing = self.processing.write();
-		for hash in block_hashes {
+		for hash in hashes {
 			processing.remove(hash);
 		}
 	}
 
-	/// Removes up to `max` verified blocks from the queue
+	/// Removes up to `max` verified items from the queue
-	pub fn drain(&self, max: usize) -> Vec<PreverifiedBlock> {
+	pub fn drain(&self, max: usize) -> Vec<K::Verified> {
 		let mut verified = self.verification.verified.lock();
 		let count = min(max, verified.len());
-		let mut result = Vec::with_capacity(count);
+		let result = verified.drain(..count).collect::<Vec<_>>();
-		for _ in 0..count {
+
-			let block = verified.pop_front().unwrap();
-			result.push(block);
-		}
 		self.ready_signal.reset();
 		if !verified.is_empty() {
 			self.ready_signal.set();
@@ -389,7 +391,7 @@ impl BlockQueue {
 	}
 
 	/// Get queue status.
-	pub fn queue_info(&self) -> BlockQueueInfo {
+	pub fn queue_info(&self) -> QueueInfo {
 		let (unverified_len, unverified_bytes) = {
 			let v = self.verification.unverified.lock();
 			(v.len(), v.heap_size_of_children())
@@ -402,7 +404,8 @@ impl BlockQueue {
 			let v = self.verification.verified.lock();
 			(v.len(), v.heap_size_of_children())
 		};
-		BlockQueueInfo {
+
+		QueueInfo {
 			unverified_queue_size: unverified_len,
 			verifying_queue_size: verifying_len,
 			verified_queue_size: verified_len,
@@ -428,22 +431,22 @@ impl BlockQueue {
 	}
 }
 
-impl MayPanic for BlockQueue {
+impl<K: Kind> MayPanic for VerificationQueue<K> {
 	fn on_panic<F>(&self, closure: F) where F: OnPanicListener {
 		self.panic_handler.on_panic(closure);
 	}
 }
 
-impl Drop for BlockQueue {
+impl<K: Kind> Drop for VerificationQueue<K> {
 	fn drop(&mut self) {
-		trace!(target: "shutdown", "[BlockQueue] Closing...");
+		trace!(target: "shutdown", "[VerificationQueue] Closing...");
 		self.clear();
 		self.deleting.store(true, AtomicOrdering::Release);
 		self.more_to_verify.notify_all();
 		for t in self.verifiers.drain(..) {
 			t.join().unwrap();
 		}
-		trace!(target: "shutdown", "[BlockQueue] Closed.");
+		trace!(target: "shutdown", "[VerificationQueue] Closed.");
 	}
 }
 
@@ -452,7 +455,8 @@ mod tests {
 	use util::*;
 	use io::*;
 	use spec::*;
-	use block_queue::*;
+	use super::{BlockQueue, Config};
+	use super::kind::blocks::Unverified;
 	use tests::helpers::*;
 	use error::*;
 	use views::*;
@@ -460,7 +464,7 @@ mod tests {
 	fn get_test_queue() -> BlockQueue {
 		let spec = get_test_spec();
 		let engine = spec.engine;
-		BlockQueue::new(BlockQueueConfig::default(), engine, IoChannel::disconnected())
+		BlockQueue::new(Config::default(), engine, IoChannel::disconnected())
 	}
 
 	#[test]
@@ -468,13 +472,13 @@ mod tests {
 		// TODO better test
 		let spec = Spec::new_test();
 		let engine = spec.engine;
-		let _ = BlockQueue::new(BlockQueueConfig::default(), engine, IoChannel::disconnected());
+		let _ = BlockQueue::new(Config::default(), engine, IoChannel::disconnected());
 	}
 
 	#[test]
 	fn can_import_blocks() {
 		let queue = get_test_queue();
-		if let Err(e) = queue.import_block(get_good_dummy_block()) {
+		if let Err(e) = queue.import(Unverified::new(get_good_dummy_block())) {
 			panic!("error importing block that is valid by definition({:?})", e);
 		}
 	}
@@ -482,11 +486,11 @@ mod tests {
 	#[test]
 	fn returns_error_for_duplicates() {
 		let queue = get_test_queue();
-		if let Err(e) = queue.import_block(get_good_dummy_block()) {
+		if let Err(e) = queue.import(Unverified::new(get_good_dummy_block())) {
 			panic!("error importing block that is valid by definition({:?})", e);
 		}
 
-		let duplicate_import = queue.import_block(get_good_dummy_block());
+		let duplicate_import = queue.import(Unverified::new(get_good_dummy_block()));
 		match duplicate_import {
 			Err(e) => {
 				match e {
@@ -503,14 +507,14 @@ mod tests {
 		let queue = get_test_queue();
 		let block = get_good_dummy_block();
 		let hash = BlockView::new(&block).header().hash().clone();
-		if let Err(e) = queue.import_block(block) {
+		if let Err(e) = queue.import(Unverified::new(block)) {
 			panic!("error importing block that is valid by definition({:?})", e);
 		}
 		queue.flush();
 		queue.drain(10);
 		queue.mark_as_good(&[ hash ]);
 
-		if let Err(e) = queue.import_block(get_good_dummy_block()) {
+		if let Err(e) = queue.import(Unverified::new(get_good_dummy_block())) {
 			panic!("error importing block that has already been drained ({:?})", e);
 		}
 	}
@@ -518,7 +522,8 @@ mod tests {
 	#[test]
 	fn returns_empty_once_finished() {
 		let queue = get_test_queue();
-		queue.import_block(get_good_dummy_block()).expect("error importing block that is valid by definition");
+		queue.import(Unverified::new(get_good_dummy_block()))
+			.expect("error importing block that is valid by definition");
 		queue.flush();
 		queue.drain(1);
 
@@ -529,13 +534,13 @@ mod tests {
 	fn test_mem_limit() {
 		let spec = get_test_spec();
 		let engine = spec.engine;
-		let mut config = BlockQueueConfig::default();
+		let mut config = Config::default();
 		config.max_mem_use = super::MIN_MEM_LIMIT;  // empty queue uses about 15000
 		let queue = BlockQueue::new(config, engine, IoChannel::disconnected());
 		assert!(!queue.queue_info().is_full());
 		let mut blocks = get_good_dummy_block_seq(50);
 		for b in blocks.drain(..) {
-			queue.import_block(b).unwrap();
+			queue.import(Unverified::new(b)).unwrap();
 		}
 		assert!(queue.queue_info().is_full());
 	}

ethcore/src/verification/verification.rs

@@ -36,14 +36,22 @@ pub struct PreverifiedBlock {
 	pub bytes: Bytes,
 }
 
+impl HeapSizeOf for PreverifiedBlock {
+	fn heap_size_of_children(&self) -> usize {
+		self.header.heap_size_of_children()
+			+ self.transactions.heap_size_of_children()
+			+ self.bytes.heap_size_of_children()
+	}
+}
+
 /// Phase 1 quick block verification. Only does checks that are cheap. Operates on a single block
 pub fn verify_block_basic(header: &Header, bytes: &[u8], engine: &Engine) -> Result<(), Error> {
-	try!(verify_header(&header, engine));
+	try!(verify_header_params(&header, engine));
 	try!(verify_block_integrity(bytes, &header.transactions_root(), &header.uncles_hash()));
 	try!(engine.verify_block_basic(&header, Some(bytes)));
 	for u in try!(UntrustedRlp::new(bytes).at(2)).iter().map(|rlp| rlp.as_val::<Header>()) {
 		let u = try!(u);
-		try!(verify_header(&u, engine));
+		try!(verify_header_params(&u, engine));
 		try!(engine.verify_block_basic(&u, None));
 	}
 	// Verify transactions.
@@ -179,7 +187,7 @@ pub fn verify_block_final(expected: &Header, got: &Header) -> Result<(), Error>
 }
 
 /// Check basic header parameters.
-fn verify_header(header: &Header, engine: &Engine) -> Result<(), Error> {
+pub fn verify_header_params(header: &Header, engine: &Engine) -> Result<(), Error> {
 	if header.number() >= From::from(BlockNumber::max_value()) {
 		return Err(From::from(BlockError::RidiculousNumber(OutOfBounds { max: Some(From::from(BlockNumber::max_value())), min: None, found: header.number() })))
 	}

ethkey/src/signature.rs

@@ -26,7 +26,6 @@ use bigint::hash::{H520, H256, FixedHash};
 use {Secret, Public, SECP256K1, Error, Message, public_to_address, Address};
 
 #[repr(C)]
-#[derive(Eq)]
 pub struct Signature([u8; 65]);
 
 impl Signature {
@@ -77,6 +76,9 @@ impl PartialEq for Signature {
 	}
 }
 
+// manual implementation required in Rust 1.13+, see `std::cmp::AssertParamIsEq`.
+impl Eq for Signature { }
+
 // also manual for the same reason, but the pretty printing might be useful.
 impl fmt::Debug for Signature {
 	fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {

ethstore/src/account/safe_account.rs

@@ -16,14 +16,14 @@
 
 use ethkey::{KeyPair, sign, Address, Secret, Signature, Message};
 use {json, Error, crypto};
-use crypto::{Keccak256};
+use crypto::Keccak256;
 use random::Random;
 use account::{Version, Cipher, Kdf, Aes128Ctr, Pbkdf2, Prf};
 
 #[derive(Debug, PartialEq, Clone)]
 pub struct Crypto {
 	pub cipher: Cipher,
-	pub ciphertext: [u8; 32],
+	pub ciphertext: Vec<u8>,
 	pub kdf: Kdf,
 	pub mac: [u8; 32],
 }
@@ -95,7 +95,7 @@ impl Crypto {
 			cipher: Cipher::Aes128Ctr(Aes128Ctr {
 				iv: iv,
 			}),
-			ciphertext: ciphertext,
+			ciphertext: ciphertext.to_vec(),
 			kdf: Kdf::Pbkdf2(Pbkdf2 {
 				dklen: crypto::KEY_LENGTH as u32,
 				salt: salt,
@@ -107,6 +107,10 @@ impl Crypto {
 	}
 
 	pub fn secret(&self, password: &str) -> Result<Secret, Error> {
+		if self.ciphertext.len() > 32 {
+			return Err(Error::InvalidSecret);
+		}
+
 		let (derived_left_bits, derived_right_bits) = match self.kdf {
 			Kdf::Pbkdf2(ref params) => crypto::derive_key_iterations(password, &params.salt, params.c),
 			Kdf::Scrypt(ref params) => crypto::derive_key_scrypt(password, &params.salt, params.n, params.p, params.r),
@@ -122,7 +126,8 @@ impl Crypto {
 
 		match self.cipher {
 			Cipher::Aes128Ctr(ref params) => {
-				crypto::aes::decrypt(&derived_left_bits, &params.iv, &self.ciphertext, &mut *secret)
+				let from = 32 - self.ciphertext.len();
+				crypto::aes::decrypt(&derived_left_bits, &params.iv, &self.ciphertext, &mut (&mut *secret)[from..])
 			},
 		}
 

ethstore/src/json/bytes.rs

@@ -0,0 +1,58 @@
+use std::{ops, str};
+use serde::{Deserialize, Deserializer, Error, Serialize, Serializer};
+use rustc_serialize::hex::{ToHex, FromHex, FromHexError};
+
+#[derive(Debug, PartialEq)]
+pub struct Bytes(Vec<u8>);
+
+impl ops::Deref for Bytes {
+	type Target = [u8];
+
+	fn deref(&self) -> &Self::Target {
+		&self.0
+	}
+}
+
+impl Deserialize for Bytes {
+	fn deserialize<D>(deserializer: &mut D) -> Result<Self, D::Error>
+		where D: Deserializer
+	{
+		let s = try!(String::deserialize(deserializer));
+		let data = try!(s.from_hex().map_err(|e| Error::custom(format!("Invalid hex value {}", e))));
+		Ok(Bytes(data))
+	}
+}
+
+impl Serialize for Bytes {
+	fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
+	where S: Serializer {
+		serializer.serialize_str(&self.0.to_hex())
+	}
+}
+
+impl str::FromStr for Bytes {
+	type Err = FromHexError;
+
+	fn from_str(s: &str) -> Result<Self, Self::Err> {
+		s.from_hex().map(Bytes)
+	}
+}
+
+impl From<&'static str> for Bytes {
+	fn from(s: &'static str) -> Self {
+		s.parse().expect(&format!("invalid string literal for {}: '{}'", stringify!(Self), s))
+	}
+}
+
+impl From<Vec<u8>> for Bytes {
+	fn from(v: Vec<u8>) -> Self {
+		Bytes(v)
+	}
+}
+
+impl From<Bytes> for Vec<u8> {
+	fn from(b: Bytes) -> Self {
+		b.0
+	}
+}
+

ethstore/src/json/crypto.rs

@@ -16,12 +16,14 @@
 
 use serde::{Deserialize, Deserializer, Serialize, Serializer, Error};
 use serde::de::{Visitor, MapVisitor};
-use super::{Cipher, CipherSer, CipherSerParams, Kdf, KdfSer, KdfSerParams, H256};
+use super::{Cipher, CipherSer, CipherSerParams, Kdf, KdfSer, KdfSerParams, H256, Bytes};
+
+pub type CipherText = Bytes;
 
 #[derive(Debug, PartialEq)]
 pub struct Crypto {
 	pub cipher: Cipher,
-	pub ciphertext: H256,
+	pub ciphertext: CipherText,
 	pub kdf: Kdf,
 	pub mac: H256,
 }

ethstore/src/json/hash.rs

@@ -14,9 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
-use std::fmt;
+use std::{ops, fmt, str};
-use std::ops;
-use std::str::FromStr;
 use rustc_serialize::hex::{FromHex, ToHex};
 use serde::{Serialize, Serializer, Deserialize, Deserializer, Error as SerdeError};
 use serde::de::Visitor;
@@ -65,7 +63,7 @@ macro_rules! impl_hash {
 					type Value = $name;
 
 					fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: SerdeError {
-						FromStr::from_str(value).map_err(SerdeError::custom)
+						value.parse().map_err(SerdeError::custom)
 					}
 
 					fn visit_string<E>(&mut self, value: String) -> Result<Self::Value, E> where E: SerdeError {
@@ -77,7 +75,7 @@ macro_rules! impl_hash {
 			}
 		}
 
-		impl FromStr for $name {
+		impl str::FromStr for $name {
 			type Err = Error;
 
 			fn from_str(value: &str) -> Result<Self, Self::Err> {
@@ -92,6 +90,12 @@ macro_rules! impl_hash {
 			}
 		}
 
+		impl From<&'static str> for $name {
+			fn from(s: &'static str) -> Self {
+				s.parse().expect(&format!("invalid string literal for {}: '{}'", stringify!(Self), s))
+			}
+		}
+
 		impl From<[u8; $size]> for $name {
 			fn from(bytes: [u8; $size]) -> Self {
 				$name(bytes)

ethstore/src/json/id.rs

@@ -15,8 +15,7 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
 //! Universaly unique identifier.
-use std::str::FromStr;
+use std::{fmt, str};
-use std::fmt;
 use rustc_serialize::hex::{ToHex, FromHex};
 use serde::{Deserialize, Serialize, Deserializer, Serializer, Error as SerdeError};
 use serde::de::Visitor;
@@ -73,7 +72,7 @@ fn copy_into(from: &str, into: &mut [u8]) -> Result<(), Error> {
 	Ok(())
 }
 
-impl FromStr for UUID {
+impl str::FromStr for UUID {
 	type Err = Error;
 
 	fn from_str(s: &str) -> Result<Self, Self::Err> {
@@ -95,6 +94,12 @@ impl FromStr for UUID {
 	}
 }
 
+impl From<&'static str> for UUID {
+	fn from(s: &'static str) -> Self {
+		s.parse().expect(&format!("invalid string literal for {}: '{}'", stringify!(Self), s))
+	}
+}
+
 impl Serialize for UUID {
 	fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
 	where S: Serializer {
@@ -116,7 +121,7 @@ impl Visitor for UUIDVisitor {
 	type Value = UUID;
 
 	fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: SerdeError {
-		UUID::from_str(value).map_err(SerdeError::custom)
+		value.parse().map_err(SerdeError::custom)
 	}
 
 	fn visit_string<E>(&mut self, value: String) -> Result<Self::Value, E> where E: SerdeError {
@@ -126,19 +131,18 @@ impl Visitor for UUIDVisitor {
 
 #[cfg(test)]
 mod tests {
-	use std::str::FromStr;
 	use super::UUID;
 
 	#[test]
 	fn uuid_from_str() {
-		let uuid = UUID::from_str("3198bc9c-6672-5ab3-d995-4942343ae5b6").unwrap();
+		let uuid: UUID = "3198bc9c-6672-5ab3-d995-4942343ae5b6".into();
 		assert_eq!(uuid, UUID::from([0x31, 0x98, 0xbc, 0x9c, 0x66, 0x72, 0x5a, 0xb3, 0xd9, 0x95, 0x49, 0x42, 0x34, 0x3a, 0xe5, 0xb6]));
 	}
 
 	#[test]
 	fn uuid_from_and_to_str() {
 		let from = "3198bc9c-6672-5ab3-d995-4942343ae5b6";
-		let uuid = UUID::from_str(from).unwrap();
+		let uuid: UUID = from.into();
 		let to: String = uuid.into();
 		assert_eq!(from, &to);
 	}

ethstore/src/json/key_file.rs

@@ -153,7 +153,7 @@ impl KeyFile {
 mod tests {
 	use std::str::FromStr;
 	use serde_json;
-	use json::{KeyFile, UUID, Version, Crypto, Cipher, Aes128Ctr, Kdf, Scrypt, H128, H160, H256};
+	use json::{KeyFile, UUID, Version, Crypto, Cipher, Aes128Ctr, Kdf, Scrypt};
 
 	#[test]
 	fn basic_keyfile() {
@@ -185,20 +185,20 @@ mod tests {
 		let expected = KeyFile {
 			id: UUID::from_str("8777d9f6-7860-4b9b-88b7-0b57ee6b3a73").unwrap(),
 			version: Version::V3,
-			address: H160::from_str("6edddfc6349aff20bc6467ccf276c5b52487f7a8").unwrap(),
+			address: "6edddfc6349aff20bc6467ccf276c5b52487f7a8".into(),
 			crypto: Crypto {
 				cipher: Cipher::Aes128Ctr(Aes128Ctr {
-					iv: H128::from_str("b5a7ec855ec9e2c405371356855fec83").unwrap(),
+					iv: "b5a7ec855ec9e2c405371356855fec83".into(),
 				}),
-				ciphertext: H256::from_str("7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc").unwrap(),
+				ciphertext: "7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc".into(),
 				kdf: Kdf::Scrypt(Scrypt {
 					n: 262144,
 					dklen: 32,
 					p: 1,
 					r: 8,
-					salt: H256::from_str("1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209").unwrap(),
+					salt: "1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209".into(),
 				}),
-				mac: H256::from_str("46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f").unwrap(),
+				mac: "46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f".into(),
 			},
 			name: Some("Test".to_owned()),
 			meta: Some("{}".to_owned()),
@@ -234,22 +234,22 @@ mod tests {
 		}"#;
 
 		let expected = KeyFile {
-			id: UUID::from_str("8777d9f6-7860-4b9b-88b7-0b57ee6b3a73").unwrap(),
+			id: "8777d9f6-7860-4b9b-88b7-0b57ee6b3a73".into(),
 			version: Version::V3,
-			address: H160::from_str("6edddfc6349aff20bc6467ccf276c5b52487f7a8").unwrap(),
+			address: "6edddfc6349aff20bc6467ccf276c5b52487f7a8".into(),
 			crypto: Crypto {
 				cipher: Cipher::Aes128Ctr(Aes128Ctr {
-					iv: H128::from_str("b5a7ec855ec9e2c405371356855fec83").unwrap(),
+					iv: "b5a7ec855ec9e2c405371356855fec83".into(),
 				}),
-				ciphertext: H256::from_str("7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc").unwrap(),
+				ciphertext: "7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc".into(),
 				kdf: Kdf::Scrypt(Scrypt {
 					n: 262144,
 					dklen: 32,
 					p: 1,
 					r: 8,
-					salt: H256::from_str("1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209").unwrap(),
+					salt: "1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209".into(),
 				}),
-				mac: H256::from_str("46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f").unwrap(),
+				mac: "46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f".into(),
 			},
 			name: None,
 			meta: None,
@@ -262,22 +262,22 @@ mod tests {
 	#[test]
 	fn to_and_from_json() {
 		let file = KeyFile {
-			id: UUID::from_str("8777d9f6-7860-4b9b-88b7-0b57ee6b3a73").unwrap(),
+			id: "8777d9f6-7860-4b9b-88b7-0b57ee6b3a73".into(),
 			version: Version::V3,
-			address: H160::from_str("6edddfc6349aff20bc6467ccf276c5b52487f7a8").unwrap(),
+			address: "6edddfc6349aff20bc6467ccf276c5b52487f7a8".into(),
 			crypto: Crypto {
 				cipher: Cipher::Aes128Ctr(Aes128Ctr {
-					iv: H128::from_str("b5a7ec855ec9e2c405371356855fec83").unwrap(),
+					iv: "b5a7ec855ec9e2c405371356855fec83".into(),
 				}),
-				ciphertext: H256::from_str("7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc").unwrap(),
+				ciphertext: "7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc".into(),
 				kdf: Kdf::Scrypt(Scrypt {
 					n: 262144,
 					dklen: 32,
 					p: 1,
 					r: 8,
-					salt: H256::from_str("1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209").unwrap(),
+					salt: "1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209".into(),
 				}),
-				mac: H256::from_str("46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f").unwrap(),
+				mac: "46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f".into(),
 			},
 			name: Some("Test".to_owned()),
 			meta: None,

ethstore/src/json/mod.rs.in

@@ -1,3 +1,4 @@
+mod bytes;
 mod cipher;
 mod crypto;
 mod error;
@@ -8,8 +9,9 @@ mod key_file;
 mod presale;
 mod version;
 
+pub use self::bytes::Bytes;
 pub use self::cipher::{Cipher, CipherSer, CipherSerParams, Aes128Ctr};
-pub use self::crypto::Crypto;
+pub use self::crypto::{Crypto, CipherText};
 pub use self::error::Error;
 pub use self::hash::{H128, H160, H256};
 pub use self::id::UUID;

ethstore/src/json/presale.rs

@@ -1,30 +1,8 @@
 use std::io::Read;
-use std::ops::Deref;
 use serde_json;
-use serde::{Deserialize, Deserializer, Error};
+use super::{H160, Bytes};
-use rustc_serialize::hex::FromHex;
-use super::{H160};
 
-#[derive(Debug, PartialEq)]
+pub type Encseed = Bytes;
-pub struct Encseed(Vec<u8>);
-
-impl Deref for Encseed {
-	type Target = [u8];
-
-	fn deref(&self) -> &Self::Target {
-		&self.0
-	}
-}
-
-impl Deserialize for Encseed {
-	fn deserialize<D>(deserializer: &mut D) -> Result<Self, D::Error>
-		where D: Deserializer
-	{
-		let s = try!(String::deserialize(deserializer));
-		let data = try!(s.from_hex().map_err(|e| Error::custom(format!("Invalid hex value {}", e))));
-		Ok(Encseed(data))
-	}
-}
 
 #[derive(Debug, PartialEq, Deserialize)]
 pub struct PresaleWallet {
@@ -43,8 +21,7 @@ impl PresaleWallet {
 mod tests {
 	use std::str::FromStr;
 	use serde_json;
-	use rustc_serialize::hex::FromHex;
+	use json::{PresaleWallet, H160};
-	use json::{PresaleWallet, H160, Encseed};
 
 	#[test]
 	fn presale_wallet() {
@@ -57,7 +34,7 @@ mod tests {
 		} "#;
 
 		let expected = PresaleWallet {
-			encseed: Encseed("137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066".from_hex().unwrap()),
+			encseed: "137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066".into(),
 			address: H160::from_str("ede84640d1a1d3e06902048e67aa7db8d52c2ce1").unwrap(),
 		};
 
@@ -77,7 +54,7 @@ mod tests {
 		} "#;
 
 		let expected = PresaleWallet {
-			encseed: Encseed("137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0d".from_hex().unwrap()),
+			encseed: "137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0d".into(),
 			address: H160::from_str("ede84640d1a1d3e06902048e67aa7db8d52c2ce1").unwrap(),
 		};
 

ethstore/tests/api.rs

@@ -19,9 +19,8 @@ extern crate ethstore;
 
 mod util;
 
-use std::str::FromStr;
 use ethstore::{SecretStore, EthStore};
-use ethstore::ethkey::{Random, Generator, Secret, Address};
+use ethstore::ethkey::{Random, Generator, Secret, KeyPair, verify_address};
 use ethstore::dir::DiskDirectory;
 use util::TransientDir;
 
@@ -103,14 +102,21 @@ fn pat_path() -> &'static str {
 	}
 }
 
+fn ciphertext_path() -> &'static str {
+	match ::std::fs::metadata("ethstore") {
+		Ok(_) => "ethstore/tests/res/ciphertext",
+		Err(_) => "tests/res/ciphertext",
+	}
+}
+
 #[test]
 fn secret_store_laod_geth_files() {
 	let dir = DiskDirectory::at(test_path());
 	let store = EthStore::open(Box::new(dir)).unwrap();
 	assert_eq!(store.accounts().unwrap(), vec![
-		Address::from_str("3f49624084b67849c7b4e805c5988c21a430f9d9").unwrap(),
+		"3f49624084b67849c7b4e805c5988c21a430f9d9".into(),
-		Address::from_str("5ba4dcf897e97c2bdf8315b9ef26c13c085988cf").unwrap(),
+		"5ba4dcf897e97c2bdf8315b9ef26c13c085988cf".into(),
-		Address::from_str("63121b431a52f8043c16fcf0d1df9cb7b5f66649").unwrap(),
+		"63121b431a52f8043c16fcf0d1df9cb7b5f66649".into(),
 	]);
 }
 
@@ -119,9 +125,30 @@ fn secret_store_load_pat_files() {
 	let dir = DiskDirectory::at(pat_path());
 	let store = EthStore::open(Box::new(dir)).unwrap();
 	assert_eq!(store.accounts().unwrap(), vec![
-		Address::from_str("3f49624084b67849c7b4e805c5988c21a430f9d9").unwrap(),
+		"3f49624084b67849c7b4e805c5988c21a430f9d9".into(),
-		Address::from_str("5ba4dcf897e97c2bdf8315b9ef26c13c085988cf").unwrap(),
+		"5ba4dcf897e97c2bdf8315b9ef26c13c085988cf".into(),
 	]);
 }
 
+#[test]
+fn test_decrypting_files_with_short_ciphertext() {
+	// 31e9d1e6d844bd3a536800ef8d8be6a9975db509, 30
+	let kp1 = KeyPair::from_secret("000081c29e8142bb6a81bef5a92bda7a8328a5c85bb2f9542e76f9b0f94fc018".into()).unwrap();
+	// d1e64e5480bfaf733ba7d48712decb8227797a4e , 31
+	let kp2 = KeyPair::from_secret("00fa7b3db73dc7dfdf8c5fbdb796d741e4488628c41fc4febd9160a866ba0f35".into()).unwrap();
+	let dir = DiskDirectory::at(ciphertext_path());
+	let store = EthStore::open(Box::new(dir)).unwrap();
+	let accounts = store.accounts().unwrap();
+	assert_eq!(accounts, vec![
+		"31e9d1e6d844bd3a536800ef8d8be6a9975db509".into(),
+		"d1e64e5480bfaf733ba7d48712decb8227797a4e".into(),
+	]);
 
+	let message = Default::default();
+
+	let s1 = store.sign(&accounts[0], "foo", &message).unwrap();
+	let s2 = store.sign(&accounts[1], "foo", &message).unwrap();
+	assert!(verify_address(&accounts[0], &s1, &message).unwrap());
+	assert!(verify_address(&kp1.address(), &s1, &message).unwrap());
+	assert!(verify_address(&kp2.address(), &s2, &message).unwrap());
+}

ethstore/tests/res/ciphertext/30.json

@@ -0,0 +1,21 @@
+{
+	"address" : "31e9d1e6d844bd3a536800ef8d8be6a9975db509",
+	"crypto" : {
+		"cipher" : "aes-128-ctr",
+		"cipherparams" : {
+			"iv" : "3ca92af36ad7c2cd92454c59cea5ef00"
+		},
+		"ciphertext" : "108b7d34f3442fc26ab1ab90ca91476ba6bfa8c00975a49ef9051dc675aa",
+		"kdf" : "scrypt",
+		"kdfparams" : {
+			"dklen" : 32,
+			"n" : 2,
+			"r" : 8,
+			"p" : 1,
+			"salt" : "d0769e608fb86cda848065642a9c6fa046845c928175662b8e356c77f914cd3b"
+		},
+		"mac" : "75d0e6759f7b3cefa319c3be41680ab6beea7d8328653474bd06706d4cc67420"
+	},
+	"id" : "a37e1559-5955-450d-8075-7b8931b392b2",
+	"version" : 3
+}

ethstore/tests/res/ciphertext/31.json

@@ -0,0 +1,21 @@
+{
+	"address" : "d1e64e5480bfaf733ba7d48712decb8227797a4e",
+	"crypto" : {
+		"cipher" : "aes-128-ctr",
+		"cipherparams" : {
+			"iv" : "e0c41130a323adc1446fc82f724bca2f"
+		},
+		"ciphertext" : "9517cd5bdbe69076f9bf5057248c6c050141e970efa36ce53692d5d59a3984",
+		"kdf" : "scrypt",
+		"kdfparams" : {
+			"dklen" : 32,
+			"n" : 2,
+			"r" : 8,
+			"p" : 1,
+			"salt" : "711f816911c92d649fb4c84b047915679933555030b3552c1212609b38208c63"
+		},
+		"mac" : "d5e116151c6aa71470e67a7d42c9620c75c4d23229847dcc127794f0732b0db5"
+	},
+	"id" : "fecfc4ce-e956-48fd-953b-30f8b52ed66c",
+	"version" : 3
+}

json/src/spec/ethash.rs

@@ -32,6 +32,9 @@ pub struct EthashParams {
 	#[serde(rename="difficultyBoundDivisor")]
 	pub difficulty_bound_divisor: Uint,
 	/// See main EthashParams docs.
+	#[serde(rename="difficultyIncrementDivisor")]
+	pub difficulty_increment_divisor: Option<Uint>,
+	/// See main EthashParams docs.
 	#[serde(rename="durationLimit")]
 	pub duration_limit: Uint,
 	/// See main EthashParams docs.
@@ -39,9 +42,11 @@ pub struct EthashParams {
 	pub block_reward: Uint,
 	/// See main EthashParams docs.
 	pub registrar: Option<Address>,
+
 	/// See main EthashParams docs.
 	#[serde(rename="frontierCompatibilityModeLimit")]
 	pub frontier_compatibility_mode_limit: Option<Uint>,
+
 	/// See main EthashParams docs.
 	#[serde(rename="daoHardforkTransition")]
 	pub dao_hardfork_transition: Option<Uint>,
@@ -51,6 +56,16 @@ pub struct EthashParams {
 	/// See main EthashParams docs.
 	#[serde(rename="daoHardforkAccounts")]
 	pub dao_hardfork_accounts: Option<Vec<Address>>,
+
+	/// See main EthashParams docs.
+	#[serde(rename="difficultyHardforkTransition")]
+	pub difficulty_hardfork_transition: Option<Uint>,
+	/// See main EthashParams docs.
+	#[serde(rename="difficultyHardforkBoundDivisor")]
+	pub difficulty_hardfork_bound_divisor: Option<Uint>,
+	/// See main EthashParams docs.
+	#[serde(rename="bombDefuseTransition")]
+	pub bomb_defuse_transition: Option<Uint>,
 }
 
 /// Ethash engine deserialization.
@@ -99,7 +114,10 @@ mod tests {
 					"0x7602b46df5390e432ef1c307d4f2c9ff6d65cc97",
 					"0xbb9bc244d798123fde783fcc1c72d3bb8c189413",
 					"0x807640a13483f8ac783c557fcdf27be11ea4ac7a"
-				]
+				],
+				"difficultyHardforkTransition": "0x59d9",
+				"difficultyHardforkBoundDivisor": "0x0200",
+				"bombDefuseTransition": "0x42"
 			}
 		}"#;
 

json/src/spec/params.rs

@@ -31,6 +31,9 @@ pub struct Params {
 	/// Network id.
 	#[serde(rename="networkID")]
 	pub network_id: Uint,
+	/// Name of the main ("eth") subprotocol.
+	#[serde(rename="subprotocolName")]
+	pub subprotocol_name: Option<String>,
 	/// Minimum gas limit.
 	#[serde(rename="minGasLimit")]
 	pub min_gas_limit: Uint,
@@ -53,6 +56,7 @@ mod tests {
 			"frontierCompatibilityModeLimit": "0x118c30",
 			"maximumExtraDataSize": "0x20",
 			"networkID" : "0x1",
+			"subprotocolName" : "exp",
 			"minGasLimit": "0x1388",
 			"accountStartNonce": "0x00"
 		}"#;

logger/src/lib.rs

@@ -91,10 +91,10 @@ pub fn setup_log(config: &Config) -> Result<Arc<RotatingLogger>, String> {
 		let timestamp = time::strftime("%Y-%m-%d %H:%M:%S %Z", &time::now()).unwrap();
 
 		let with_color = if max_log_level() <= LogLevelFilter::Info {
-			format!("{}{}", Colour::Black.bold().paint(timestamp), record.args())
+			format!("{} {}", Colour::Black.bold().paint(timestamp), record.args())
 		} else {
 			let name = thread::current().name().map_or_else(Default::default, |x| format!("{}", Colour::Blue.bold().paint(x)));
-			format!("{}{} {} {}  {}", Colour::Black.bold().paint(timestamp), name, record.level(), record.target(), record.args())
+			format!("{} {} {} {}  {}", Colour::Black.bold().paint(timestamp), name, record.level(), record.target(), record.args())
 		};
 
 		let removed_color = kill_color(with_color.as_ref());

parity/cli/usage.txt

@@ -31,8 +31,8 @@ Operating Options:
                            (default: {flag_mode_alarm}).
   --chain CHAIN            Specify the blockchain type. CHAIN may be either a
                            JSON chain specification file or olympic, frontier,
-                           homestead, mainnet, morden, classic or testnet
+                           homestead, mainnet, morden, classic, expanse or
-                           (default: {flag_chain}).
+                           testnet (default: {flag_chain}).
   -d --db-path PATH        Specify the database & configuration directory path
                            (default: {flag_db_path}).
   --keys-path PATH         Specify the path for JSON key files to be found

parity/migration.rs

@@ -43,13 +43,15 @@ pub enum Error {
 	/// Returned when current version cannot be read or guessed.
 	UnknownDatabaseVersion,
 	/// Migration does not support existing pruning algorithm.
-	UnsuportedPruningMethod,
+	UnsupportedPruningMethod,
 	/// Existing DB is newer than the known one.
 	FutureDBVersion,
 	/// Migration is not possible.
 	MigrationImpossible,
 	/// Migration unexpectadly failed.
 	MigrationFailed,
+	/// Internal migration error.
+	Internal(MigrationError),
 	/// Migration was completed succesfully,
 	/// but there was a problem with io.
 	Io(IoError),
@@ -59,10 +61,11 @@ impl Display for Error {
 	fn fmt(&self, f: &mut Formatter) -> Result<(), FmtError> {
 		let out = match *self {
 			Error::UnknownDatabaseVersion => "Current database version cannot be read".into(),
-			Error::UnsuportedPruningMethod => "Unsupported pruning method for database migration. Delete DB and resync.".into(),
+			Error::UnsupportedPruningMethod => "Unsupported pruning method for database migration. Delete DB and resync.".into(),
 			Error::FutureDBVersion => "Database was created with newer client version. Upgrade your client or delete DB and resync.".into(),
 			Error::MigrationImpossible => format!("Database migration to version {} is not possible.", CURRENT_VERSION),
 			Error::MigrationFailed => "Database migration unexpectedly failed".into(),
+			Error::Internal(ref err) => format!("{}", err),
 			Error::Io(ref err) => format!("Unexpected io error on DB migration: {}.", err),
 		};
 
@@ -80,7 +83,7 @@ impl From<MigrationError> for Error {
 	fn from(err: MigrationError) -> Self {
 		match err {
 			MigrationError::Io(e) => Error::Io(e),
-			_ => Error::MigrationFailed,
+			_ => Error::Internal(err),
 		}
 	}
 }
@@ -160,7 +163,7 @@ fn consolidate_database(
 	let config = default_migration_settings(compaction_profile);
 	let mut db_config = DatabaseConfig {
 		max_open_files: 64,
-		cache_size: None,
+		cache_sizes: Default::default(),
 		compaction: config.compaction_profile,
 		columns: None,
 		wal: true,
@@ -320,7 +323,7 @@ mod legacy {
 		let res = match pruning {
 			Algorithm::Archive => manager.add_migration(migrations::state::ArchiveV7::default()),
 			Algorithm::OverlayRecent => manager.add_migration(migrations::state::OverlayRecentV7::default()),
-			_ => return Err(Error::UnsuportedPruningMethod),
+			_ => return Err(Error::UnsupportedPruningMethod),
 		};
 
 		try!(res.map_err(|_| Error::MigrationImpossible));

parity/params.rs

@@ -29,6 +29,7 @@ pub enum SpecType {
 	Testnet,
 	Olympic,
 	Classic,
+	Expanse,
 	Custom(String),
 }
 
@@ -47,6 +48,7 @@ impl str::FromStr for SpecType {
 			"frontier-dogmatic" | "homestead-dogmatic" | "classic" => SpecType::Classic,
 			"morden" | "testnet" => SpecType::Testnet,
 			"olympic" => SpecType::Olympic,
+			"expanse" => SpecType::Expanse,
 			other => SpecType::Custom(other.into()),
 		};
 		Ok(spec)
@@ -60,6 +62,7 @@ impl SpecType {
 			SpecType::Testnet => Ok(ethereum::new_morden()),
 			SpecType::Olympic => Ok(ethereum::new_olympic()),
 			SpecType::Classic => Ok(ethereum::new_classic()),
+			SpecType::Expanse => Ok(ethereum::new_expanse()),
 			SpecType::Custom(ref filename) => {
 				let file = try!(fs::File::open(filename).map_err(|_| "Could not load specification file."));
 				Spec::load(file)

parity/run.rs

@@ -148,6 +148,11 @@ pub fn execute(cmd: RunCmd) -> Result<(), String> {
 		Some(id) => id,
 		None => spec.network_id(),
 	};
+	if spec.subprotocol_name().len() != 3 {
+		warn!("Your chain specification's subprotocol length is not 3. Ignoring.");
+	} else {
+		sync_config.subprotocol_name.clone_from_slice(spec.subprotocol_name().as_bytes());
+	}
 	sync_config.fork_block = spec.fork_block();
 
 	// prepare account provider

rpc/Cargo.toml

@@ -25,6 +25,7 @@ ethsync = { path = "../sync" }
 ethjson = { path = "../json" }
 ethcore-devtools = { path = "../devtools" }
 rlp = { path = "../util/rlp" }
+fetch = { path = "../util/fetch" }
 rustc-serialize = "0.3"
 transient-hashmap = "0.1"
 serde_macros = { version = "0.8.0", optional = true }

rpc/src/lib.rs

@@ -36,6 +36,7 @@ extern crate json_ipc_server as ipc;
 extern crate ethcore_ipc;
 extern crate time;
 extern crate rlp;
+extern crate fetch;
 
 #[macro_use]
 extern crate log;

rpc/src/v1/helpers/errors.rs

@@ -23,6 +23,7 @@ macro_rules! rpc_unimplemented {
 use std::fmt;
 use ethcore::error::Error as EthcoreError;
 use ethcore::account_provider::{Error as AccountError};
+use fetch::FetchError;
 use jsonrpc_core::{Error, ErrorCode, Value};
 
 mod codes {
@@ -41,6 +42,7 @@ mod codes {
 	pub const REQUEST_REJECTED_LIMIT: i64 = -32041;
 	pub const REQUEST_NOT_FOUND: i64 = -32042;
 	pub const COMPILATION_ERROR: i64 = -32050;
+	pub const FETCH_ERROR: i64 = -32060;
 }
 
 pub fn unimplemented() -> Error {
@@ -155,6 +157,14 @@ pub fn signer_disabled() -> Error {
 	}
 }
 
+pub fn from_fetch_error(error: FetchError) -> Error {
+	Error {
+		code: ErrorCode::ServerError(codes::FETCH_ERROR),
+		message: "Error while fetching content.".into(),
+		data: Some(Value::String(format!("{:?}", error))),
+	}
+}
+
 pub fn from_signing_error(error: AccountError) -> Error {
 	Error {
 		code: ErrorCode::ServerError(codes::ACCOUNT_LOCKED),

rpc/src/v1/impls/eth.rs

@@ -424,13 +424,9 @@ impl<C, S: ?Sized, M, EM> Eth for EthClient<C, S, M, EM> where
 
 	fn transaction_by_hash(&self, hash: RpcH256) -> Result<Option<Transaction>, Error> {
 		try!(self.active());
-
-		let miner = take_weak!(self.miner);
 		let hash: H256 = hash.into();
-		match miner.transaction(&hash) {
+		let miner = take_weak!(self.miner);
-			Some(pending_tx) => Ok(Some(pending_tx.into())),
+		Ok(try!(self.transaction(TransactionID::Hash(hash))).or_else(|| miner.transaction(&hash).map(Into::into)))
-			None => self.transaction(TransactionID::Hash(hash))
-		}
 	}
 
 	fn transaction_by_block_hash_and_index(&self, hash: RpcH256, index: Index) -> Result<Option<Transaction>, Error> {

rpc/src/v1/impls/ethcore.rs

@@ -15,30 +15,33 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
 //! Ethcore-specific rpc implementation.
-use std::sync::{Arc, Weak};
+use std::{fs, io};
+use std::sync::{mpsc, Arc, Weak};
 use std::str::FromStr;
 use std::collections::{BTreeMap};
-use util::{RotatingLogger, Address};
+use util::{RotatingLogger, Address, Mutex, sha3};
 use util::misc::version_data;
 
 use crypto::ecies;
+use fetch::{Client as FetchClient, Fetch};
 use ethkey::{Brain, Generator};
 use ethstore::random_phrase;
 use ethsync::{SyncProvider, ManageNetwork};
 use ethcore::miner::MinerService;
 use ethcore::client::{MiningBlockChainClient};
 
-use jsonrpc_core::*;
+use jsonrpc_core::{from_params, to_value, Value, Error, Params, Ready};
 use v1::traits::Ethcore;
-use v1::types::{Bytes, U256, H160, H512, Peers, Transaction};
+use v1::types::{Bytes, U256, H160, H256, H512, Peers, Transaction};
 use v1::helpers::{errors, SigningQueue, SignerService, NetworkSettings};
 use v1::helpers::params::expect_no_params;
 
 /// Ethcore implementation.
-pub struct EthcoreClient<C, M, S: ?Sized> where
+pub struct EthcoreClient<C, M, S: ?Sized, F=FetchClient> where
 	C: MiningBlockChainClient,
 	M: MinerService,
-	S: SyncProvider {
+	S: SyncProvider,
+	F: Fetch {
 
 	client: Weak<C>,
 	miner: Weak<M>,
@@ -47,10 +50,14 @@ pub struct EthcoreClient<C, M, S: ?Sized> where
 	logger: Arc<RotatingLogger>,
 	settings: Arc<NetworkSettings>,
 	signer: Option<Arc<SignerService>>,
+	fetch: Mutex<F>
 }
 
-impl<C, M, S: ?Sized> EthcoreClient<C, M, S> where C: MiningBlockChainClient, M: MinerService, S: SyncProvider {
+impl<C, M, S: ?Sized> EthcoreClient<C, M, S> where
-	/// Creates new `EthcoreClient`.
+	C: MiningBlockChainClient,
+	M: MinerService,
+	S: SyncProvider, {
+	/// Creates new `EthcoreClient` with default `Fetch`.
 	pub fn new(
 		client: &Arc<C>,
 		miner: &Arc<M>,
@@ -60,6 +67,26 @@ impl<C, M, S: ?Sized> EthcoreClient<C, M, S> where C: MiningBlockChainClient, M:
 		settings: Arc<NetworkSettings>,
 		signer: Option<Arc<SignerService>>
 	) -> Self {
+		Self::with_fetch(client, miner, sync, net, logger, settings, signer)
+	}
+}
+
+impl<C, M, S: ?Sized, F> EthcoreClient<C, M, S, F> where
+	C: MiningBlockChainClient,
+	M: MinerService,
+	S: SyncProvider,
+	F: Fetch, {
+
+	/// Creates new `EthcoreClient` with customizable `Fetch`.
+	pub fn with_fetch(
+		client: &Arc<C>,
+		miner: &Arc<M>,
+		sync: &Arc<S>,
+		net: &Arc<ManageNetwork>,
+		logger: Arc<RotatingLogger>,
+		settings: Arc<NetworkSettings>,
+		signer: Option<Arc<SignerService>>
+		) -> Self {
 		EthcoreClient {
 			client: Arc::downgrade(client),
 			miner: Arc::downgrade(miner),
@@ -68,6 +95,7 @@ impl<C, M, S: ?Sized> EthcoreClient<C, M, S> where C: MiningBlockChainClient, M:
 			logger: logger,
 			settings: settings,
 			signer: signer,
+			fetch: Mutex::new(F::default()),
 		}
 	}
 
@@ -78,7 +106,11 @@ impl<C, M, S: ?Sized> EthcoreClient<C, M, S> where C: MiningBlockChainClient, M:
 	}
 }
 
-impl<C, M, S: ?Sized> Ethcore for EthcoreClient<C, M, S> where M: MinerService + 'static, C: MiningBlockChainClient + 'static, S: SyncProvider + 'static {
+impl<C, M, S: ?Sized, F> Ethcore for EthcoreClient<C, M, S, F> where
+	M: MinerService + 'static,
+	C: MiningBlockChainClient + 'static,
+	S: SyncProvider + 'static,
+	F: Fetch + 'static {
 
 	fn transactions_limit(&self, params: Params) -> Result<Value, Error> {
 		try!(self.active());
@@ -233,4 +265,42 @@ impl<C, M, S: ?Sized> Ethcore for EthcoreClient<C, M, S> where M: MinerService +
 
 		Ok(to_value(&take_weak!(self.miner).all_transactions().into_iter().map(Into::into).collect::<Vec<Transaction>>()))
 	}
+
+	fn hash_content(&self, params: Params, ready: Ready) {
+		let res = self.active().and_then(|_| from_params::<(String,)>(params));
+
+		let hash_content = |result| {
+			let path = try!(result);
+			let mut file = io::BufReader::new(try!(fs::File::open(&path)));
+			// Try to hash
+			let result = sha3(&mut file);
+			// Remove file (always)
+			try!(fs::remove_file(&path));
+			// Return the result
+			Ok(try!(result))
+		};
+
+		match res {
+			Err(e) => ready.ready(Err(e)),
+			Ok((url, )) => {
+				let (tx, rx) = mpsc::channel();
+				let res = self.fetch.lock().request_async(&url, Default::default(), Box::new(move |result| {
+					let result = hash_content(result)
+							.map_err(errors::from_fetch_error)
+							.map(|hash| to_value(H256::from(hash)));
+
+					// Receive ready and invoke with result.
+					let ready: Ready = rx.try_recv().expect("When on_done is invoked ready object is always sent.");
+					ready.ready(result);
+				}));
+
+				// Either invoke ready right away or transfer it to the closure.
+				if let Err(e) = res {
+					ready.ready(Err(errors::from_fetch_error(e)));
+				} else {
+					tx.send(ready).expect("Rx end is sent to on_done closure.");
+				}
+			}
+		}
+	}
 }

rpc/src/v1/tests/helpers/fetch.rs

@@ -0,0 +1,44 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Test implementation of fetch client.
+
+use std::io::Write;
+use std::{env, fs, thread};
+use std::sync::Arc;
+use std::sync::atomic::AtomicBool;
+use fetch::{Fetch, FetchError, FetchResult};
+
+/// Test implementation of fetcher. Will always return the same file.
+#[derive(Default)]
+pub struct TestFetch;
+
+impl Fetch for TestFetch {
+	fn request_async(&mut self, _url: &str, _abort: Arc<AtomicBool>, on_done: Box<Fn(FetchResult) + Send>) -> Result<(), FetchError> {
+		thread::spawn(move || {
+			let mut path = env::temp_dir();
+			path.push(Self::random_filename());
+
+			let mut file = fs::File::create(&path).unwrap();
+			file.write_all(b"Some content").unwrap();
+
+			on_done(Ok(path));
+		});
+		Ok(())
+	}
+}
+
+

rpc/src/v1/tests/helpers/mod.rs

@@ -18,6 +18,8 @@
 
 mod sync_provider;
 mod miner_service;
+mod fetch;
 
 pub use self::sync_provider::{Config, TestSyncProvider};
 pub use self::miner_service::TestMinerService;
+pub use self::fetch::TestFetch;

rpc/src/v1/tests/mocked/ethcore.rs

@@ -23,7 +23,7 @@ use ethcore::client::{TestBlockChainClient};
 use jsonrpc_core::IoHandler;
 use v1::{Ethcore, EthcoreClient};
 use v1::helpers::{SignerService, NetworkSettings};
-use v1::tests::helpers::{TestSyncProvider, Config, TestMinerService};
+use v1::tests::helpers::{TestSyncProvider, Config, TestMinerService, TestFetch};
 use super::manage_network::TestManageNetwork;
 
 fn miner_service() -> Arc<TestMinerService> {
@@ -60,12 +60,15 @@ fn network_service() -> Arc<ManageNetwork> {
 	Arc::new(TestManageNetwork)
 }
 
+type TestEthcoreClient = EthcoreClient<TestBlockChainClient, TestMinerService, TestSyncProvider, TestFetch>;
+
 fn ethcore_client(
 	client: &Arc<TestBlockChainClient>,
 	miner: &Arc<TestMinerService>,
 	sync: &Arc<TestSyncProvider>,
-	net: &Arc<ManageNetwork>) -> EthcoreClient<TestBlockChainClient, TestMinerService, TestSyncProvider> {
+	net: &Arc<ManageNetwork>)
-	EthcoreClient::new(client, miner, sync, net, logger(), settings(), None)
+	-> TestEthcoreClient {
+	EthcoreClient::with_fetch(client, miner, sync, net, logger(), settings(), None)
 }
 
 #[test]
@@ -140,9 +143,9 @@ fn rpc_ethcore_dev_logs() {
 	let logger = logger();
 	logger.append("a".to_owned());
 	logger.append("b".to_owned());
-	let ethcore = EthcoreClient::new(&client, &miner, &sync, &net, logger.clone(), settings(), None).to_delegate();
+	let ethcore: TestEthcoreClient = EthcoreClient::with_fetch(&client, &miner, &sync, &net, logger.clone(), settings(), None);
 	let io = IoHandler::new();
-	io.add_delegate(ethcore);
+	io.add_delegate(ethcore.to_delegate());
 
 	let request = r#"{"jsonrpc": "2.0", "method": "ethcore_devLogs", "params":[], "id": 1}"#;
 	let response = r#"{"jsonrpc":"2.0","result":["b","a"],"id":1}"#;
@@ -263,8 +266,8 @@ fn rpc_ethcore_unsigned_transactions_count() {
 	let net = network_service();
 	let io = IoHandler::new();
 	let signer = Arc::new(SignerService::new_test());
-	let ethcore = EthcoreClient::new(&client, &miner, &sync, &net, logger(), settings(), Some(signer)).to_delegate();
+	let ethcore: TestEthcoreClient = EthcoreClient::with_fetch(&client, &miner, &sync, &net, logger(), settings(), Some(signer));
-	io.add_delegate(ethcore);
+	io.add_delegate(ethcore.to_delegate());
 
 	let request = r#"{"jsonrpc": "2.0", "method": "ethcore_unsignedTransactionsCount", "params":[], "id": 1}"#;
 	let response = r#"{"jsonrpc":"2.0","result":0,"id":1}"#;
@@ -287,6 +290,21 @@ fn rpc_ethcore_unsigned_transactions_count_when_signer_disabled() {
 	assert_eq!(io.handle_request_sync(request), Some(response.to_owned()));
 }
 
+#[test]
+fn rpc_ethcore_hash_content() {
+	let miner = miner_service();
+	let client = client_service();
+	let sync = sync_provider();
+	let net = network_service();
+	let io = IoHandler::new();
+	io.add_delegate(ethcore_client(&client, &miner, &sync, &net).to_delegate());
+
+	let request = r#"{"jsonrpc": "2.0", "method": "ethcore_hashContent", "params":["https://ethcore.io/assets/images/ethcore-black-horizontal.png"], "id": 1}"#;
+	let response = r#"{"jsonrpc":"2.0","result":"0x2be00befcf008bc0e7d9cdefc194db9c75352e8632f48498b5a6bfce9f02c88e","id":1}"#;
+
+	assert_eq!(io.handle_request_sync(request), Some(response.to_owned()));
+}
+
 #[test]
 fn rpc_ethcore_pending_transactions() {
 	let miner = miner_service();

rpc/src/v1/traits/ethcore.rs

@@ -83,6 +83,9 @@ pub trait Ethcore: Sized + Send + Sync + 'static {
 	/// Returns all pending (current) transactions from transaction queue.
 	fn pending_transactions(&self, _: Params) -> Result<Value, Error>;
 
+	/// Hash a file content under given URL.
+	fn hash_content(&self, _: Params, _: Ready);
+
 	/// Should be used to convert object to io delegate.
 	fn to_delegate(self) -> IoDelegate<Self> {
 		let mut delegate = IoDelegate::new(Arc::new(self));
@@ -107,6 +110,8 @@ pub trait Ethcore: Sized + Send + Sync + 'static {
 		delegate.add_method("ethcore_registryAddress", Ethcore::registry_address);
 		delegate.add_method("ethcore_encryptMessage", Ethcore::encrypt_message);
 		delegate.add_method("ethcore_pendingTransactions", Ethcore::pending_transactions);
+		delegate.add_async_method("ethcore_hashContent", Ethcore::hash_content);
+
 		delegate
 	}
 }

rpc/src/v1/types/hash.rs

@@ -25,9 +25,10 @@ use util::{H64 as Eth64, H160 as Eth160, H256 as Eth256, H520 as Eth520, H512 as
 macro_rules! impl_hash {
 	($name: ident, $other: ident, $size: expr) => {
 		/// Hash serialization
-		#[derive(Eq)]
 		pub struct $name([u8; $size]);
 
+		impl Eq for $name { }
+
 		impl Default for $name {
 			fn default() -> Self {
 				$name([0; $size])

rpc/src/v1/types/trace.rs

@@ -414,15 +414,15 @@ pub struct LocalizedTrace {
 	/// Result
 	result: Res,
 	/// Trace address
-	trace_address: Vec<U256>,
+	trace_address: Vec<usize>,
 	/// Subtraces
-	subtraces: U256,
+	subtraces: usize,
 	/// Transaction position
-	transaction_position: U256,
+	transaction_position: usize,
 	/// Transaction hash
 	transaction_hash: H256,
 	/// Block Number
-	block_number: U256,
+	block_number: u64,
 	/// Block Hash
 	block_hash: H256,
 }
@@ -485,9 +485,9 @@ impl From<EthLocalizedTrace> for LocalizedTrace {
 #[derive(Debug)]
 pub struct Trace {
 	/// Trace address
-	trace_address: Vec<U256>,
+	trace_address: Vec<usize>,
 	/// Subtraces
-	subtraces: U256,
+	subtraces: usize,
 	/// Action
 	action: Action,
 	/// Result
@@ -601,15 +601,15 @@ mod tests {
 				gas_used: 8.into(),
 				output: vec![0x56, 0x78].into(),
 			}),
-			trace_address: vec![10.into()],
+			trace_address: vec![10],
-			subtraces: 1.into(),
+			subtraces: 1,
-			transaction_position: 11.into(),
+			transaction_position: 11,
 			transaction_hash: 12.into(),
-			block_number: 13.into(),
+			block_number: 13,
 			block_hash: 14.into(),
 		};
 		let serialized = serde_json::to_string(&t).unwrap();
-		assert_eq!(serialized, r#"{"type":"call","action":{"from":"0x0000000000000000000000000000000000000004","to":"0x0000000000000000000000000000000000000005","value":"0x6","gas":"0x7","input":"0x1234","callType":"call"},"result":{"gasUsed":"0x8","output":"0x5678"},"traceAddress":["0xa"],"subtraces":"0x1","transactionPosition":"0xb","transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":"0xd","blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
+		assert_eq!(serialized, r#"{"type":"call","action":{"from":"0x0000000000000000000000000000000000000004","to":"0x0000000000000000000000000000000000000005","value":"0x6","gas":"0x7","input":"0x1234","callType":"call"},"result":{"gasUsed":"0x8","output":"0x5678"},"traceAddress":[10],"subtraces":1,"transactionPosition":11,"transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":13,"blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
 	}
 
 	#[test]
@@ -624,15 +624,15 @@ mod tests {
 				call_type: CallType::Call,
 			}),
 			result: Res::FailedCall(TraceError::OutOfGas),
-			trace_address: vec![10.into()],
+			trace_address: vec![10],
-			subtraces: 1.into(),
+			subtraces: 1,
-			transaction_position: 11.into(),
+			transaction_position: 11,
 			transaction_hash: 12.into(),
-			block_number: 13.into(),
+			block_number: 13,
 			block_hash: 14.into(),
 		};
 		let serialized = serde_json::to_string(&t).unwrap();
-		assert_eq!(serialized, r#"{"type":"call","action":{"from":"0x0000000000000000000000000000000000000004","to":"0x0000000000000000000000000000000000000005","value":"0x6","gas":"0x7","input":"0x1234","callType":"call"},"error":"Out of gas","traceAddress":["0xa"],"subtraces":"0x1","transactionPosition":"0xb","transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":"0xd","blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
+		assert_eq!(serialized, r#"{"type":"call","action":{"from":"0x0000000000000000000000000000000000000004","to":"0x0000000000000000000000000000000000000005","value":"0x6","gas":"0x7","input":"0x1234","callType":"call"},"error":"Out of gas","traceAddress":[10],"subtraces":1,"transactionPosition":11,"transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":13,"blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
 	}
 
 	#[test]
@@ -649,15 +649,15 @@ mod tests {
 				code: vec![0x56, 0x78].into(),
 				address: 0xff.into(),
 			}),
-			trace_address: vec![10.into()],
+			trace_address: vec![10],
-			subtraces: 1.into(),
+			subtraces: 1,
-			transaction_position: 11.into(),
+			transaction_position: 11,
 			transaction_hash: 12.into(),
-			block_number: 13.into(),
+			block_number: 13,
 			block_hash: 14.into(),
 		};
 		let serialized = serde_json::to_string(&t).unwrap();
-		assert_eq!(serialized, r#"{"type":"create","action":{"from":"0x0000000000000000000000000000000000000004","value":"0x6","gas":"0x7","init":"0x1234"},"result":{"gasUsed":"0x8","code":"0x5678","address":"0x00000000000000000000000000000000000000ff"},"traceAddress":["0xa"],"subtraces":"0x1","transactionPosition":"0xb","transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":"0xd","blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
+		assert_eq!(serialized, r#"{"type":"create","action":{"from":"0x0000000000000000000000000000000000000004","value":"0x6","gas":"0x7","init":"0x1234"},"result":{"gasUsed":"0x8","code":"0x5678","address":"0x00000000000000000000000000000000000000ff"},"traceAddress":[10],"subtraces":1,"transactionPosition":11,"transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":13,"blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
 	}
 
 	#[test]
@@ -670,15 +670,15 @@ mod tests {
 				init: Bytes::new(vec![0x12, 0x34]),
 			}),
 			result: Res::FailedCreate(TraceError::OutOfGas),
-			trace_address: vec![10.into()],
+			trace_address: vec![10],
-			subtraces: 1.into(),
+			subtraces: 1,
-			transaction_position: 11.into(),
+			transaction_position: 11,
 			transaction_hash: 12.into(),
-			block_number: 13.into(),
+			block_number: 13,
 			block_hash: 14.into(),
 		};
 		let serialized = serde_json::to_string(&t).unwrap();
-		assert_eq!(serialized, r#"{"type":"create","action":{"from":"0x0000000000000000000000000000000000000004","value":"0x6","gas":"0x7","init":"0x1234"},"error":"Out of gas","traceAddress":["0xa"],"subtraces":"0x1","transactionPosition":"0xb","transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":"0xd","blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
+		assert_eq!(serialized, r#"{"type":"create","action":{"from":"0x0000000000000000000000000000000000000004","value":"0x6","gas":"0x7","init":"0x1234"},"error":"Out of gas","traceAddress":[10],"subtraces":1,"transactionPosition":11,"transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":13,"blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
 	}
 
 	#[test]
@@ -690,15 +690,15 @@ mod tests {
 				balance: 7.into(),
 			}),
 			result: Res::None,
-			trace_address: vec![10.into()],
+			trace_address: vec![10],
-			subtraces: 1.into(),
+			subtraces: 1,
-			transaction_position: 11.into(),
+			transaction_position: 11,
 			transaction_hash: 12.into(),
-			block_number: 13.into(),
+			block_number: 13,
 			block_hash: 14.into(),
 		};
 		let serialized = serde_json::to_string(&t).unwrap();
-		assert_eq!(serialized, r#"{"type":"suicide","action":{"address":"0x0000000000000000000000000000000000000004","refundAddress":"0x0000000000000000000000000000000000000006","balance":"0x7"},"result":null,"traceAddress":["0xa"],"subtraces":"0x1","transactionPosition":"0xb","transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":"0xd","blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
+		assert_eq!(serialized, r#"{"type":"suicide","action":{"address":"0x0000000000000000000000000000000000000004","refundAddress":"0x0000000000000000000000000000000000000006","balance":"0x7"},"result":null,"traceAddress":[10],"subtraces":1,"transactionPosition":11,"transactionHash":"0x000000000000000000000000000000000000000000000000000000000000000c","blockNumber":13,"blockHash":"0x000000000000000000000000000000000000000000000000000000000000000e"}"#);
 	}
 
 	#[test]

rpc/src/v1/types/uint.rs

@@ -23,9 +23,11 @@ use util::{U256 as EthU256, Uint};
 macro_rules! impl_uint {
 	($name: ident, $other: ident, $size: expr) => {
 		/// Uint serialization.
-		#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
+		#[derive(Debug, Default, Clone, Copy, PartialEq, Hash)]
 		pub struct $name($other);
 
+		impl Eq for $name { }
+
 		impl<T> From<T> for $name where $other: From<T> {
 			fn from(o: T) -> Self {
 				$name($other::from(o))

sync/src/api.rs

@@ -15,6 +15,7 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
 use std::sync::Arc;
+use std::str;
 use network::{NetworkProtocolHandler, NetworkService, NetworkContext, PeerId,
 	NetworkConfiguration as BasicNetworkConfiguration, NonReservedPeerMode, NetworkError};
 use util::{U256, H256};
@@ -31,9 +32,9 @@ use std::str::FromStr;
 use parking_lot::RwLock;
 
 /// Ethereum sync protocol
-pub const ETH_PROTOCOL: &'static str = "eth";
+pub const ETH_PROTOCOL: [u8; 3] = *b"eth";
 /// Infinity protocol
-pub const INF_PROTOCOL: &'static str = "inf";
+pub const INF_PROTOCOL: [u8; 3] = *b"inf";
 
 /// Sync configuration
 #[derive(Debug, Clone, Copy)]
@@ -42,6 +43,8 @@ pub struct SyncConfig {
 	pub max_download_ahead_blocks: usize,
 	/// Network ID
 	pub network_id: U256,
+	/// Main "eth" subprotocol name.
+	pub subprotocol_name: [u8; 3],
 	/// Fork block to check
 	pub fork_block: Option<(BlockNumber, H256)>,
 }
@@ -51,6 +54,7 @@ impl Default for SyncConfig {
 		SyncConfig {
 			max_download_ahead_blocks: 20000,
 			network_id: U256::from(1),
+			subprotocol_name: ETH_PROTOCOL,
 			fork_block: None,
 		}
 	}
@@ -73,6 +77,8 @@ pub struct EthSync {
 	eth_handler: Arc<SyncProtocolHandler>,
 	/// Infinity Protocol handler
 	inf_handler: Arc<InfProtocolHandler>,
+	/// The main subprotocol name
+	subprotocol_name: [u8; 3],
 }
 
 impl EthSync {
@@ -85,6 +91,7 @@ impl EthSync {
 			network: service,
 			eth_handler: Arc::new(SyncProtocolHandler { sync: RwLock::new(chain_sync), chain: chain.clone(), snapshot_service: snapshot_service.clone() }),
 			inf_handler: Arc::new(InfProtocolHandler { sync: RwLock::new(inf_sync), chain: chain, snapshot_service: snapshot_service }),
+			subprotocol_name: config.subprotocol_name,
 		});
 
 		Ok(sync)
@@ -171,7 +178,7 @@ impl ChainNotify for EthSync {
 		sealed: Vec<H256>,
 		_duration: u64)
 	{
-		self.network.with_context(ETH_PROTOCOL, |context| {
+		self.network.with_context(self.subprotocol_name, |context| {
 			let mut sync_io = NetSyncIo::new(context, &*self.eth_handler.chain, &*self.eth_handler.snapshot_service);
 			self.eth_handler.sync.write().chain_new_blocks(
 				&mut sync_io,
@@ -185,7 +192,7 @@ impl ChainNotify for EthSync {
 
 	fn start(&self) {
 		self.network.start().unwrap_or_else(|e| warn!("Error starting network: {:?}", e));
-		self.network.register_protocol(self.eth_handler.clone(), ETH_PROTOCOL, &[62u8, 63u8, 64u8])
+		self.network.register_protocol(self.eth_handler.clone(), self.subprotocol_name, &[62u8, 63u8, 64u8])
 			.unwrap_or_else(|e| warn!("Error registering ethereum protocol: {:?}", e));
 		self.network.register_protocol(self.inf_handler.clone(), INF_PROTOCOL, &[1u8])
 			.unwrap_or_else(|e| warn!("Error registering infinity protocol: {:?}", e));
@@ -249,7 +256,7 @@ impl ManageNetwork for EthSync {
 	}
 
 	fn stop_network(&self) {
-		self.network.with_context(ETH_PROTOCOL, |context| {
+		self.network.with_context(self.subprotocol_name, |context| {
 			let mut sync_io = NetSyncIo::new(context, &*self.eth_handler.chain, &*self.eth_handler.snapshot_service);
 			self.eth_handler.sync.write().abort(&mut sync_io);
 		});

sync/src/blocks.rs

@@ -19,7 +19,7 @@ use rlp::*;
 use network::NetworkError;
 use ethcore::header::{ Header as BlockHeader};
 
-known_heap_size!(0, HeaderId, SyncBlock);
+known_heap_size!(0, HeaderId);
 
 /// Block data with optional body.
 struct SyncBlock {
@@ -27,6 +27,12 @@ struct SyncBlock {
 	body: Option<Bytes>,
 }
 
+impl HeapSizeOf for SyncBlock {
+	fn heap_size_of_children(&self) -> usize {
+		self.header.heap_size_of_children() + self.body.heap_size_of_children()
+	}
+}
+
 /// Used to identify header by transactions and uncles hashes
 #[derive(Eq, PartialEq, Hash)]
 struct HeaderId {
@@ -219,10 +225,14 @@ impl BlockCollection {
 		self.blocks.contains_key(hash)
 	}
 
-	/// Return heap size.
+	/// Return used heap size.
 	pub fn heap_size(&self) -> usize {
-		//TODO: other collections
+		self.heads.heap_size_of_children()
-		self.blocks.heap_size_of_children()
+			+ self.blocks.heap_size_of_children()
+			+ self.parents.heap_size_of_children()
+			+ self.header_ids.heap_size_of_children()
+			+ self.downloading_headers.heap_size_of_children()
+			+ self.downloading_bodies.heap_size_of_children()
 	}
 
 	/// Check if given block hash is marked as being downloaded.

sync/src/sync_io.rs

@@ -17,7 +17,6 @@
 use network::{NetworkContext, PeerId, PacketId, NetworkError};
 use ethcore::client::BlockChainClient;
 use ethcore::snapshot::SnapshotService;
-use api::ETH_PROTOCOL;
 
 /// IO interface for the syning handler.
 /// Provides peer connection management and an interface to the blockchain client.
@@ -101,7 +100,7 @@ impl<'s, 'h> SyncIo for NetSyncIo<'s, 'h> {
 	}
 
 	fn eth_protocol_version(&self, peer_id: PeerId) -> u8 {
-		self.network.protocol_version(peer_id, ETH_PROTOCOL).unwrap_or(0)
+		self.network.protocol_version(peer_id, self.network.subprotocol_name()).unwrap_or(0)
 	}
 }
 

util/bigint/src/hash.rs

@@ -64,11 +64,11 @@ pub fn clean_0x(s: &str) -> &str {
 
 macro_rules! impl_hash {
 	($from: ident, $size: expr) => {
-		#[derive(Eq)]
 		#[repr(C)]
 		/// Unformatted binary data of fixed length.
 		pub struct $from (pub [u8; $size]);
 
+
 		impl From<[u8; $size]> for $from {
 			fn from(bytes: [u8; $size]) -> Self {
 				$from(bytes)
@@ -210,6 +210,8 @@ macro_rules! impl_hash {
 			}
 		}
 
+		impl Eq for $from {}
+
 		impl PartialEq for $from {
 			fn eq(&self, other: &Self) -> bool {
 				for i in 0..$size {

util/fetch/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+description = "HTTP/HTTPS fetching library"
+homepage = "http://ethcore.io"
+license = "GPL-3.0"
+name = "fetch"
+version = "0.1.0"
+authors = ["Ethcore <admin@ethcore.io>"]
+
+[dependencies]
+log = "0.3"
+rand = "0.3"
+hyper = { default-features = false, git = "https://github.com/ethcore/hyper" }
+https-fetch = { path = "../https-fetch" }
+clippy = { version = "0.0.90", optional = true}
+
+[features]
+default = []
+dev = ["clippy"]

util/fetch/src/client.rs

@@ -0,0 +1,146 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Fetching
+
+use std::{env, io};
+use std::sync::{mpsc, Arc};
+use std::sync::atomic::AtomicBool;
+use std::path::PathBuf;
+
+use hyper;
+use https_fetch as https;
+
+use fetch_file::{FetchHandler, Error as HttpFetchError};
+
+pub type FetchResult = Result<PathBuf, FetchError>;
+
+#[derive(Debug)]
+pub enum FetchError {
+	InvalidUrl,
+	Http(HttpFetchError),
+	Https(https::FetchError),
+	Io(io::Error),
+	Other(String),
+}
+
+impl From<HttpFetchError> for FetchError {
+	fn from(e: HttpFetchError) -> Self {
+		FetchError::Http(e)
+	}
+}
+
+impl From<io::Error> for FetchError {
+	fn from(e: io::Error) -> Self {
+		FetchError::Io(e)
+	}
+}
+
+pub trait Fetch: Default + Send {
+	/// Fetch URL and get the result in callback.
+	fn request_async(&mut self, url: &str, abort: Arc<AtomicBool>, on_done: Box<Fn(FetchResult) + Send>) -> Result<(), FetchError>;
+
+	/// Fetch URL and get a result Receiver. You will be notified when receiver is ready by `on_done` callback.
+	fn request(&mut self, url: &str, abort: Arc<AtomicBool>, on_done: Box<Fn() + Send>) -> Result<mpsc::Receiver<FetchResult>, FetchError> {
+		let (tx, rx) = mpsc::channel();
+		try!(self.request_async(url, abort, Box::new(move |result| {
+			let res = tx.send(result);
+			if let Err(_) = res {
+				warn!("Fetch finished, but no one was listening");
+			}
+			on_done();
+		})));
+		Ok(rx)
+	}
+
+	/// Closes this client
+	fn close(self) {}
+
+	/// Returns a random filename
+	fn random_filename() -> String {
+		use ::rand::Rng;
+		let mut rng = ::rand::OsRng::new().unwrap();
+		rng.gen_ascii_chars().take(12).collect()
+	}
+}
+
+pub struct Client {
+	http_client: hyper::Client<FetchHandler>,
+	https_client: https::Client,
+	limit: Option<usize>,
+}
+
+impl Default for Client {
+	fn default() -> Self {
+		// Max 15MB will be downloaded.
+		Client::with_limit(Some(15*1024*1024))
+	}
+}
+
+impl Client {
+	fn with_limit(limit: Option<usize>) -> Self {
+		Client {
+			http_client: hyper::Client::new().expect("Unable to initialize http client."),
+			https_client: https::Client::with_limit(limit).expect("Unable to initialize https client."),
+			limit: limit,
+		}
+	}
+
+	fn convert_url(url: hyper::Url) -> Result<https::Url, FetchError> {
+		let host = format!("{}", try!(url.host().ok_or(FetchError::InvalidUrl)));
+		let port = try!(url.port_or_known_default().ok_or(FetchError::InvalidUrl));
+		https::Url::new(&host, port, url.path()).map_err(|_| FetchError::InvalidUrl)
+	}
+
+	fn temp_path() -> PathBuf {
+		let mut dir = env::temp_dir();
+		dir.push(Self::random_filename());
+		dir
+	}
+}
+
+impl Fetch for Client {
+	fn close(self) {
+		self.http_client.close();
+		self.https_client.close();
+	}
+
+	fn request_async(&mut self, url: &str, abort: Arc<AtomicBool>, on_done: Box<Fn(FetchResult) + Send>) -> Result<(), FetchError> {
+		let is_https = url.starts_with("https://");
+		let url = try!(url.parse().map_err(|_| FetchError::InvalidUrl));
+		let temp_path = Self::temp_path();
+
+		trace!(target: "fetch", "Fetching from: {:?}", url);
+
+		if is_https {
+			let url = try!(Self::convert_url(url));
+			try!(self.https_client.fetch_to_file(
+				url,
+				temp_path.clone(),
+				abort,
+				move |result| on_done(result.map(|_| temp_path).map_err(FetchError::Https)),
+			).map_err(|e| FetchError::Other(format!("{:?}", e))));
+		} else {
+			try!(self.http_client.request(
+				url,
+				FetchHandler::new(temp_path, abort, Box::new(move |result| on_done(result)), self.limit.map(|v| v as u64).clone()),
+			).map_err(|e| FetchError::Other(format!("{:?}", e))));
+		}
+
+		Ok(())
+	}
+}
+

util/fetch/src/fetch_file.rs

@@ -16,12 +16,11 @@
 
 //! Hyper Client Handler to Fetch File
 
-use std::{env, io, fs, fmt};
+use std::{io, fs, fmt};
 use std::path::PathBuf;
-use std::sync::{mpsc, Arc};
+use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::time::Duration;
-use random_filename;
 
 use hyper::status::StatusCode;
 use hyper::client::{Request, Response, DefaultTransport as HttpStream};
@@ -34,30 +33,31 @@ use super::FetchError;
 pub enum Error {
 	Aborted,
 	NotStarted,
+	SizeLimit,
 	UnexpectedStatus(StatusCode),
 	IoError(io::Error),
 	HyperError(hyper::Error),
 }
 
 pub type FetchResult = Result<PathBuf, FetchError>;
-pub type OnDone = Box<Fn() + Send>;
+pub type OnDone = Box<Fn(FetchResult) + Send>;
 
-pub struct Fetch {
+pub struct FetchHandler {
 	path: PathBuf,
 	abort: Arc<AtomicBool>,
 	file: Option<fs::File>,
 	result: Option<FetchResult>,
-	sender: mpsc::Sender<FetchResult>,
 	on_done: Option<OnDone>,
+	size_limit: Option<u64>,
 }
 
-impl fmt::Debug for Fetch {
+impl fmt::Debug for FetchHandler {
 	fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
 		write!(f, "Fetch {{ path: {:?}, file: {:?}, result: {:?} }}", self.path, self.file, self.result)
 	}
 }
 
-impl Drop for Fetch {
+impl Drop for FetchHandler {
     fn drop(&mut self) {
 		let res = self.result.take().unwrap_or(Err(Error::NotStarted.into()));
 		// Remove file if there was an error
@@ -69,40 +69,35 @@ impl Drop for Fetch {
 			}
 		}
 		// send result
-		let _ = self.sender.send(res);
 		if let Some(f) = self.on_done.take() {
-			f();
+			f(res);
 		}
     }
 }
 
-impl Fetch {
+impl FetchHandler {
-	pub fn new(sender: mpsc::Sender<FetchResult>, abort: Arc<AtomicBool>, on_done: OnDone) -> Self {
+	pub fn new(path: PathBuf, abort: Arc<AtomicBool>, on_done: OnDone, size_limit: Option<u64>) -> Self {
-		let mut dir = env::temp_dir();
+		FetchHandler {
-		dir.push(random_filename());
+			path: path,
-
-		Fetch {
-			path: dir,
 			abort: abort,
 			file: None,
 			result: None,
-			sender: sender,
 			on_done: Some(on_done),
+			size_limit: size_limit,
 		}
 	}
-}
 
-impl Fetch {
 	fn is_aborted(&self) -> bool {
 		self.abort.load(Ordering::SeqCst)
 	}
+
 	fn mark_aborted(&mut self) -> Next {
 		self.result = Some(Err(Error::Aborted.into()));
 		Next::end()
 	}
 }
 
-impl hyper::client::Handler<HttpStream> for Fetch {
+impl hyper::client::Handler<HttpStream> for FetchHandler {
     fn on_request(&mut self, req: &mut Request) -> Next {
 		if self.is_aborted() {
 			return self.mark_aborted();
@@ -147,7 +142,19 @@ impl hyper::client::Handler<HttpStream> for Fetch {
 		}
         match io::copy(decoder, self.file.as_mut().expect("File is there because on_response has created it.")) {
             Ok(0) => Next::end(),
-            Ok(_) => read(),
+            Ok(bytes_read) => match self.size_limit {
+				None => read(),
+				// Check limit
+				Some(limit) if limit > bytes_read => {
+					self.size_limit = Some(limit - bytes_read);
+					read()
+				},
+				// Size limit reached
+				_ => {
+					self.result = Some(Err(Error::SizeLimit.into()));
+					Next::end()
+				},
+			},
             Err(e) => match e.kind() {
                 io::ErrorKind::WouldBlock => Next::read(),
                 _ => {

util/fetch/src/lib.rs

@@ -14,21 +14,16 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
-//! Block queue info types
+//! A service to fetch any HTTP / HTTPS content.
 
-/// Block queue status
+#[macro_use]
-#[derive(Debug, Binary)]
+extern crate log;
-pub struct BlockQueueInfo {
+extern crate hyper;
-	/// Number of queued blocks pending verification
+extern crate https_fetch;
-	pub unverified_queue_size: usize,
+extern crate rand;
-	/// Number of verified queued blocks pending import
+
-	pub verified_queue_size: usize,
+
-	/// Number of blocks being verified
+pub mod client;
-	pub verifying_queue_size: usize,
+pub mod fetch_file;
-	/// Configured maximum number of blocks in the queue
+
-	pub max_queue_size: usize,
+pub use self::client::{Client, Fetch, FetchError, FetchResult};
-	/// Configured maximum number of bytes to use
-	pub max_mem_use: usize,
-	/// Heap memory used in bytes
-	pub mem_used: usize,
-}

util/https-fetch/src/client.rs

@@ -78,6 +78,10 @@ impl Drop for Client {
 
 impl Client {
 	pub fn new() -> Result<Self, FetchError> {
+		Self::with_limit(None)
+	}
+
+	pub fn with_limit(size_limit: Option<usize>) -> Result<Self, FetchError> {
 		let mut event_loop = try!(mio::EventLoop::new());
 		let channel = event_loop.channel();
 
@@ -85,6 +89,7 @@ impl Client {
 			let mut client = ClientLoop {
 				next_token: 0,
 				sessions: HashMap::new(),
+				size_limit: size_limit,
 			};
 			event_loop.run(&mut client).unwrap();
 		});
@@ -128,6 +133,7 @@ impl Client {
 pub struct ClientLoop {
 	next_token: usize,
 	sessions: HashMap<usize, TlsClient>,
+	size_limit: Option<usize>,
 }
 
 impl mio::Handler for ClientLoop {
@@ -154,7 +160,7 @@ impl mio::Handler for ClientLoop {
 				let token = self.next_token;
 				self.next_token += 1;
 
-				if let Ok(mut tlsclient) = TlsClient::new(mio::Token(token), &url, writer, abort, callback) {
+				if let Ok(mut tlsclient) = TlsClient::new(mio::Token(token), &url, writer, abort, callback, self.size_limit.clone()) {
 					let httpreq = format!(
 						"GET {} HTTP/1.1\r\nHost: {}\r\nConnection: close\r\nAccept-Encoding: identity\r\n\r\n",
 						url.path(),

util/https-fetch/src/http.rs

@@ -35,18 +35,20 @@ pub struct HttpProcessor {
 	status: Option<String>,
 	headers: Vec<String>,
 	body_writer: io::BufWriter<Box<io::Write>>,
+	size_limit: Option<usize>,
 }
 
 const BREAK_LEN: usize = 2;
 
 impl HttpProcessor {
-	pub fn new(body_writer: Box<io::Write>) -> Self {
+	pub fn new(body_writer: Box<io::Write>, size_limit: Option<usize>) -> Self {
 		HttpProcessor {
 			state: State::WaitingForStatus,
 			buffer: Cursor::new(Vec::new()),
 			status: None,
 			headers: Vec::new(),
-			body_writer: io::BufWriter::new(body_writer)
+			body_writer: io::BufWriter::new(body_writer),
+			size_limit: size_limit,
 		}
 	}
 
@@ -140,6 +142,15 @@ impl HttpProcessor {
 				},
 				State::WritingBody => {
 					let len = self.buffer.get_ref().len();
+					match self.size_limit {
+						None => {},
+						Some(limit) if limit > len => {},
+						_ => {
+							warn!("Finishing file fetching because limit was reached.");
+							self.set_state(State::Finished);
+							continue;
+						}
+					}
 					try!(self.body_writer.write_all(self.buffer.get_ref()));
 					self.buffer_consume(len);
 					return Ok(());
@@ -167,6 +178,17 @@ impl HttpProcessor {
 				},
 				// Buffers the data until we have a full chunk
 				State::WritingChunk(left) if self.buffer.get_ref().len() >= left => {
+					match self.size_limit {
+						None => {},
+						Some(limit) if limit > left => {
+							self.size_limit = Some(limit - left);
+						},
+						_ => {
+							warn!("Finishing file fetching because limit was reached.");
+							self.set_state(State::Finished);
+							continue;
+						}
+					}
 					try!(self.body_writer.write_all(&self.buffer.get_ref()[0..left]));
 					self.buffer_consume(left + BREAK_LEN);
 
@@ -230,7 +252,7 @@ mod tests {
 	#[test]
 	fn should_be_able_to_process_status_line() {
 		// given
-		let mut http = HttpProcessor::new(Box::new(Cursor::new(Vec::new())));
+		let mut http = HttpProcessor::new(Box::new(Cursor::new(Vec::new())), None);
 
 		// when
 		let out =
@@ -249,7 +271,7 @@ mod tests {
 	#[test]
 	fn should_be_able_to_process_headers() {
 		// given
-		let mut http = HttpProcessor::new(Box::new(Cursor::new(Vec::new())));
+		let mut http = HttpProcessor::new(Box::new(Cursor::new(Vec::new())), None);
 
 		// when
 		let out =
@@ -274,7 +296,7 @@ mod tests {
 	fn should_be_able_to_consume_body() {
 		// given
 		let (writer, data) = Writer::new();
-		let mut http = HttpProcessor::new(Box::new(writer));
+		let mut http = HttpProcessor::new(Box::new(writer), None);
 
 		// when
 		let out =
@@ -301,7 +323,7 @@ mod tests {
 	fn should_correctly_handle_chunked_content() {
 		// given
 		let (writer, data) = Writer::new();
-		let mut http = HttpProcessor::new(Box::new(writer));
+		let mut http = HttpProcessor::new(Box::new(writer), None);
 
 		// when
 		let out =
@@ -331,4 +353,40 @@ mod tests {
 		assert_eq!(data.borrow().get_ref()[..], b"Parity in\r\n\r\nchunks."[..]);
 		assert_eq!(http.state(), State::Finished);
 	}
+
+	#[test]
+	fn should_stop_fetching_when_limit_is_reached() {
+		// given
+		let (writer, data) = Writer::new();
+		let mut http = HttpProcessor::new(Box::new(writer), Some(5));
+
+		// when
+		let out =
+			"\
+				HTTP/1.1 200 OK\r\n\
+				Host: 127.0.0.1:8080\r\n\
+				Transfer-Encoding: chunked\r\n\
+				Connection: close\r\n\
+				\r\n\
+				4\r\n\
+				Pari\r\n\
+				3\r\n\
+				ty \r\n\
+				D\r\n\
+				in\r\n\
+				\r\n\
+				chunks.\r\n\
+				0\r\n\
+				\r\n\
+			";
+		http.write_all(out.as_bytes()).unwrap();
+		http.flush().unwrap();
+
+		// then
+		assert_eq!(http.status().unwrap(), "HTTP/1.1 200 OK");
+		assert_eq!(http.headers().len(), 3);
+		assert_eq!(data.borrow().get_ref()[..], b"Pari"[..]);
+		assert_eq!(http.state(), State::Finished);
+	}
+
 }

util/https-fetch/src/tlsclient.rs

@@ -87,6 +87,7 @@ impl TlsClient {
 		writer: Box<io::Write + Send>,
 		abort: Arc<AtomicBool>,
 		mut callback: Box<FnMut(FetchResult) + Send>,
+		size_limit: Option<usize>,
 		) -> Result<Self, FetchError> {
 			let res = TlsClient::make_config().and_then(|cfg| {
 				TcpStream::connect(url.address()).map(|sock| {
@@ -98,7 +99,7 @@ impl TlsClient {
 				Ok((cfg, sock)) => Ok(TlsClient {
 					abort: abort,
 					token: token,
-					writer: HttpProcessor::new(writer),
+					writer: HttpProcessor::new(writer, size_limit),
 					socket: sock,
 					closing: false,
 					error: None,

util/network/src/host.rs

@@ -137,7 +137,7 @@ const SYS_TIMER: usize = LAST_SESSION + 1;
 /// Protocol handler level packet id
 pub type PacketId = u8;
 /// Protocol / handler id
-pub type ProtocolId = &'static str;
+pub type ProtocolId = [u8; 3];
 
 /// Messages used to communitate with the event loop from other threads.
 #[derive(Clone)]
@@ -185,7 +185,7 @@ pub struct CapabilityInfo {
 impl Encodable for CapabilityInfo {
 	fn rlp_append(&self, s: &mut RlpStream) {
 		s.begin_list(2);
-		s.append(&self.protocol);
+		s.append(&&self.protocol[..]);
 		s.append(&self.version);
 	}
 }
@@ -284,10 +284,13 @@ impl<'s> NetworkContext<'s> {
 	}
 
 	/// Returns max version for a given protocol.
-	pub fn protocol_version(&self, peer: PeerId, protocol: &str) -> Option<u8> {
+	pub fn protocol_version(&self, peer: PeerId, protocol: ProtocolId) -> Option<u8> {
 		let session = self.resolve_session(peer);
 		session.and_then(|s| s.lock().capability_version(protocol))
 	}
+
+	/// Returns this object's subprotocol name.
+	pub fn subprotocol_name(&self) -> ProtocolId { self.protocol }
 }
 
 /// Shared host information
@@ -801,8 +804,8 @@ impl Host {
 							}
 						}
 						for (p, _) in self.handlers.read().iter() {
-							if s.have_capability(p)  {
+							if s.have_capability(*p) {
-								ready_data.push(p);
+								ready_data.push(*p);
 							}
 						}
 					},
@@ -811,7 +814,7 @@ impl Host {
 						protocol,
 						packet_id,
 					}) => {
-						match self.handlers.read().get(protocol) {
+						match self.handlers.read().get(&protocol) {
 							None => { warn!(target: "network", "No handler found for protocol: {:?}", protocol) },
 							Some(_) => packet_data.push((protocol, packet_id, data)),
 						}
@@ -826,13 +829,13 @@ impl Host {
 		}
 		let handlers = self.handlers.read();
 		for p in ready_data {
-			let h = handlers.get(p).unwrap().clone();
+			let h = handlers.get(&p).unwrap().clone();
 			self.stats.inc_sessions();
 			let reserved = self.reserved_nodes.read();
 			h.connected(&NetworkContext::new(io, p, session.clone(), self.sessions.clone(), &reserved), &token);
 		}
 		for (p, packet_id, data) in packet_data {
-			let h = handlers.get(p).unwrap().clone();
+			let h = handlers.get(&p).unwrap().clone();
 			let reserved = self.reserved_nodes.read();
 			h.read(&NetworkContext::new(io, p, session.clone(), self.sessions.clone(), &reserved), &token, packet_id, &data[1..]);
 		}
@@ -857,8 +860,8 @@ impl Host {
 					if s.is_ready() {
 						self.num_sessions.fetch_sub(1, AtomicOrdering::SeqCst);
 						for (p, _) in self.handlers.read().iter() {
-							if s.have_capability(p)  {
+							if s.have_capability(*p)  {
-								to_disconnect.push(p);
+								to_disconnect.push(*p);
 							}
 						}
 					}
@@ -874,7 +877,7 @@ impl Host {
 			}
 		}
 		for p in to_disconnect {
-			let h = self.handlers.read().get(p).unwrap().clone();
+			let h = self.handlers.read().get(&p).unwrap().clone();
 			let reserved = self.reserved_nodes.read();
 			h.disconnected(&NetworkContext::new(io, p, expired_session.clone(), self.sessions.clone(), &reserved), &token);
 		}
@@ -980,7 +983,7 @@ impl IoHandler<NetworkIoMessage> for Host {
 				self.nodes.write().clear_useless();
 			},
 			_ => match self.timers.read().get(&token).cloned() {
-				Some(timer) => match self.handlers.read().get(timer.protocol).cloned() {
+				Some(timer) => match self.handlers.read().get(&timer.protocol).cloned() {
 					None => { warn!(target: "network", "No handler found for protocol: {:?}", timer.protocol) },
 					Some(h) => {
 						let reserved = self.reserved_nodes.read();
@@ -1004,11 +1007,11 @@ impl IoHandler<NetworkIoMessage> for Host {
 			} => {
 				let h = handler.clone();
 				let reserved = self.reserved_nodes.read();
-				h.initialize(&NetworkContext::new(io, protocol, None, self.sessions.clone(), &reserved));
+				h.initialize(&NetworkContext::new(io, *protocol, None, self.sessions.clone(), &reserved));
-				self.handlers.write().insert(protocol, h);
+				self.handlers.write().insert(*protocol, h);
 				let mut info = self.info.write();
 				for v in versions {
-					info.capabilities.push(CapabilityInfo { protocol: protocol, version: *v, packet_count:0 });
+					info.capabilities.push(CapabilityInfo { protocol: *protocol, version: *v, packet_count:0 });
 				}
 			},
 			NetworkIoMessage::AddTimer {
@@ -1023,7 +1026,7 @@ impl IoHandler<NetworkIoMessage> for Host {
 					*counter += 1;
 					handler_token
 				};
-				self.timers.write().insert(handler_token, ProtocolTimer { protocol: protocol, token: *token });
+				self.timers.write().insert(handler_token, ProtocolTimer { protocol: *protocol, token: *token });
 				io.register_timer(handler_token, *delay).unwrap_or_else(|e| debug!("Error registering timer {}: {:?}", token, e));
 			},
 			NetworkIoMessage::Disconnect(ref peer) => {

util/network/src/lib.rs

@@ -45,7 +45,7 @@
 //!
 //! fn main () {
 //! 	let mut service = NetworkService::new(NetworkConfiguration::new_local()).expect("Error creating network service");
-//! 	service.register_protocol(Arc::new(MyHandler), "myproto", &[1u8]);
+//! 	service.register_protocol(Arc::new(MyHandler), *b"myp", &[1u8]);
 //! 	service.start().expect("Error starting service");
 //!
 //! 	// Wait for quit condition

util/network/src/session.rs

@@ -14,8 +14,8 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
+use std::{str, io};
 use std::net::SocketAddr;
-use std::io;
 use std::sync::*;
 use mio::*;
 use mio::tcp::*;
@@ -63,7 +63,7 @@ pub enum SessionData {
 		/// Packet data
 		data: Vec<u8>,
 		/// Packet protocol ID
-		protocol: &'static str,
+		protocol: [u8; 3],
 		/// Zero based packet ID
 		packet_id: u8,
 	},
@@ -89,15 +89,21 @@ pub struct SessionInfo {
 
 #[derive(Debug, PartialEq, Eq)]
 pub struct PeerCapabilityInfo {
-	pub protocol: String,
+	pub protocol: ProtocolId,
 	pub version: u8,
 }
 
 impl Decodable for PeerCapabilityInfo {
 	fn decode<D>(decoder: &D) -> Result<Self, DecoderError> where D: Decoder {
 		let c = decoder.as_rlp();
+		let p: Vec<u8> = try!(c.val_at(0));
+		if p.len() != 3 {
+			return Err(DecoderError::Custom("Invalid subprotocol string length. Should be 3"));
+		}
+		let mut p2: ProtocolId = [0u8; 3];
+		p2.clone_from_slice(&p);
 		Ok(PeerCapabilityInfo {
-			protocol: try!(c.val_at(0)),
+			protocol: p2,
 			version: try!(c.val_at(1))
 		})
 	}
@@ -105,7 +111,7 @@ impl Decodable for PeerCapabilityInfo {
 
 #[derive(Debug)]
 struct SessionCapabilityInfo {
-	pub protocol: &'static str,
+	pub protocol: [u8; 3],
 	pub version: u8,
 	pub packet_count: u8,
 	pub id_offset: u8,
@@ -239,12 +245,12 @@ impl Session {
 	}
 
 	/// Checks if peer supports given capability
-	pub fn have_capability(&self, protocol: &str) -> bool {
+	pub fn have_capability(&self, protocol: [u8; 3]) -> bool {
 		self.info.capabilities.iter().any(|c| c.protocol == protocol)
 	}
 
 	/// Checks if peer supports given capability
-	pub fn capability_version(&self, protocol: &str) -> Option<u8> {
+	pub fn capability_version(&self, protocol: [u8; 3]) -> Option<u8> {
 		self.info.capabilities.iter().filter_map(|c| if c.protocol == protocol { Some(c.version) } else { None }).max()
 	}
 
@@ -270,10 +276,10 @@ impl Session {
 	}
 
 	/// Send a protocol packet to peer.
-	pub fn send_packet<Message>(&mut self, io: &IoContext<Message>, protocol: &str, packet_id: u8, data: &[u8]) -> Result<(), NetworkError>
+	pub fn send_packet<Message>(&mut self, io: &IoContext<Message>, protocol: [u8; 3], packet_id: u8, data: &[u8]) -> Result<(), NetworkError>
         where Message: Send + Sync + Clone {
 		if self.info.capabilities.is_empty() || !self.had_hello {
-			debug!(target: "network", "Sending to unconfirmed session {}, protocol: {}, packet: {}", self.token(), protocol, packet_id);
+			debug!(target: "network", "Sending to unconfirmed session {}, protocol: {}, packet: {}", self.token(), str::from_utf8(&protocol[..]).unwrap_or("??"), packet_id);
 			return Err(From::from(NetworkError::BadProtocol));
 		}
 		if self.expired() {

util/network/src/tests.rs

@@ -41,7 +41,7 @@ impl TestProtocol {
 	/// Creates and register protocol with the network service
 	pub fn register(service: &mut NetworkService, drop_session: bool) -> Arc<TestProtocol> {
 		let handler = Arc::new(TestProtocol::new(drop_session));
-		service.register_protocol(handler.clone(), "test", &[42u8, 43u8]).expect("Error registering test protocol handler");
+		service.register_protocol(handler.clone(), *b"tst", &[42u8, 43u8]).expect("Error registering test protocol handler");
 		handler
 	}
 
@@ -93,7 +93,7 @@ impl NetworkProtocolHandler for TestProtocol {
 fn net_service() {
 	let service = NetworkService::new(NetworkConfiguration::new_local()).expect("Error creating network service");
 	service.start().unwrap();
-	service.register_protocol(Arc::new(TestProtocol::new(false)), "myproto", &[1u8]).unwrap();
+	service.register_protocol(Arc::new(TestProtocol::new(false)), *b"myp", &[1u8]).unwrap();
 }
 
 #[test]

util/src/kvdb.rs

@@ -143,12 +143,12 @@ impl CompactionProfile {
 }
 
 /// Database configuration
-#[derive(Clone, Copy)]
+#[derive(Clone)]
 pub struct DatabaseConfig {
 	/// Max number of open files.
 	pub max_open_files: i32,
-	/// Cache-size
+	/// Cache sizes (in MiB) for specific columns.
-	pub cache_size: Option<usize>,
+	pub cache_sizes: HashMap<Option<u32>, usize>,
 	/// Compaction profile
 	pub compaction: CompactionProfile,
 	/// Set number of columns
@@ -159,17 +159,23 @@ pub struct DatabaseConfig {
 
 impl DatabaseConfig {
 	/// Create new `DatabaseConfig` with default parameters and specified set of columns.
+	/// Note that cache sizes must be explicitly set.
 	pub fn with_columns(columns: Option<u32>) -> Self {
 		let mut config = Self::default();
 		config.columns = columns;
 		config
 	}
+
+	/// Set the column cache size in MiB.
+	pub fn set_cache(&mut self, col: Option<u32>, size: usize) {
+		self.cache_sizes.insert(col, size);
+	}
 }
 
 impl Default for DatabaseConfig {
 	fn default() -> DatabaseConfig {
 		DatabaseConfig {
-			cache_size: None,
+			cache_sizes: HashMap::new(),
 			max_open_files: 512,
 			compaction: CompactionProfile::default(),
 			columns: None,
@@ -213,6 +219,9 @@ impl Database {
 
 	/// Open database file. Creates if it does not exist.
 	pub fn open(config: &DatabaseConfig, path: &str) -> Result<Database, String> {
+		// default cache size for columns not specified.
+		const DEFAULT_CACHE: usize = 2;
+
 		let mut opts = Options::new();
 		if let Some(rate_limit) = config.compaction.write_rate_limit {
 			try!(opts.set_parsed_options(&format!("rate_limiter_bytes_per_sec={}", rate_limit)));
@@ -232,17 +241,22 @@ impl Database {
 
 		let mut cf_options = Vec::with_capacity(config.columns.unwrap_or(0) as usize);
 
-		for _ in 0 .. config.columns.unwrap_or(0) {
+		for col in 0 .. config.columns.unwrap_or(0) {
 			let mut opts = Options::new();
 			opts.set_compaction_style(DBCompactionStyle::DBUniversalCompaction);
 			opts.set_target_file_size_base(config.compaction.initial_file_size);
 			opts.set_target_file_size_multiplier(config.compaction.file_size_multiplier);
-			if let Some(cache_size) = config.cache_size {
+
+			let col_opt = config.columns.map(|_| col);
+
+			{
+				let cache_size = config.cache_sizes.get(&col_opt).cloned().unwrap_or(DEFAULT_CACHE);
 				let mut block_opts = BlockBasedOptions::new();
-				// all goes to read cache
+				// all goes to read cache.
 				block_opts.set_cache(Cache::new(cache_size * 1024 * 1024));
 				opts.set_block_based_table_factory(&block_opts);
 			}
+
 			cf_options.push(opts);
 		}
 

util/src/migration/mod.rs

@@ -20,6 +20,7 @@ mod tests;
 
 use std::collections::BTreeMap;
 use std::fs;
+use std::fmt;
 use std::path::{Path, PathBuf};
 
 use ::kvdb::{CompactionProfile, Database, DatabaseConfig, DBTransaction};
@@ -96,6 +97,17 @@ pub enum Error {
 	Custom(String),
 }
 
+impl fmt::Display for Error {
+	fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+		match *self {
+			Error::CannotAddMigration => write!(f, "Cannot add migration"),
+			Error::MigrationImpossible => write!(f, "Migration impossible"),
+			Error::Io(ref err) => write!(f, "{}", err),
+			Error::Custom(ref err) => write!(f, "{}", err),
+		}
+	}
+}
+
 impl From<::std::io::Error> for Error {
 	fn from(e: ::std::io::Error) -> Self {
 		Error::Io(e)
@@ -104,6 +116,8 @@ impl From<::std::io::Error> for Error {
 
 /// A generalized migration from the given db to a destination db.
 pub trait Migration: 'static {
+	/// Number of columns in the database before the migration.
+	fn pre_columns(&self) -> Option<u32> { self.columns() }
 	/// Number of columns in database after the migration.
 	fn columns(&self) -> Option<u32>;
 	/// Version of the database after the migration.
@@ -195,6 +209,7 @@ impl Manager {
 			Some(last) => migration.version() > last.version(),
 			None => true,
 		};
+
 		match is_new {
 			true => Ok(self.migrations.push(Box::new(migration))),
 			false => Err(Error::CannotAddMigration),
@@ -205,12 +220,14 @@ impl Manager {
 	/// and producing a path where the final migration lives.
 	pub fn execute(&mut self, old_path: &Path, version: u32) -> Result<PathBuf, Error> {
 		let config = self.config.clone();
-		let columns = self.no_of_columns_at(version);
 		let migrations = self.migrations_from(version);
 		if migrations.is_empty() { return Err(Error::MigrationImpossible) };
+
+		let columns = migrations.iter().find(|m| m.version() == version).and_then(|m| m.pre_columns());
+
 		let mut db_config = DatabaseConfig {
 			max_open_files: 64,
-			cache_size: None,
+			cache_sizes: Default::default(),
 			compaction: config.compaction_profile,
 			columns: columns,
 			wal: true,
@@ -267,14 +284,6 @@ impl Manager {
 	fn migrations_from(&mut self, version: u32) -> Vec<&mut Box<Migration>> {
 		self.migrations.iter_mut().filter(|m| m.version() > version).collect()
 	}
-
-	fn no_of_columns_at(&self, version: u32) -> Option<u32> {
-		let migration = self.migrations.iter().find(|m| m.version() == version);
-		match migration {
-			Some(m) => m.columns(),
-			None => None
-		}
-	}
 }
 
 /// Prints a dot every `max` ticks

util/src/migration/tests.rs

@@ -19,7 +19,7 @@
 //! are performed in temp sub-directories.
 
 use common::*;
-use migration::{Config, SimpleMigration, Manager};
+use migration::{Batch, Config, Error, SimpleMigration, Migration, Manager};
 use kvdb::Database;
 
 use devtools::RandomTempPath;
@@ -62,11 +62,10 @@ impl SimpleMigration for Migration0 {
 
 	fn version(&self) -> u32 { 1 }
 
-	fn simple_migrate(&mut self, key: Vec<u8>, value: Vec<u8>) -> Option<(Vec<u8>, Vec<u8>)> {
+	fn simple_migrate(&mut self, mut key: Vec<u8>, mut value: Vec<u8>) -> Option<(Vec<u8>, Vec<u8>)> {
-		let mut key = key;
 		key.push(0x11);
-		let mut value = value;
 		value.push(0x22);
+
 		Some((key, value))
 	}
 }
@@ -83,6 +82,31 @@ impl SimpleMigration for Migration1 {
 	}
 }
 
+struct AddsColumn;
+
+impl Migration for AddsColumn {
+	fn pre_columns(&self) -> Option<u32> { None }
+
+	fn columns(&self) -> Option<u32> { Some(1) }
+
+	fn version(&self) -> u32 { 1 }
+
+	fn migrate(&mut self, source: &Database, config: &Config, dest: &mut Database, col: Option<u32>) -> Result<(), Error> {
+		let mut batch = Batch::new(config, col);
+
+		for (key, value) in source.iter(col) {
+			try!(batch.insert(key.to_vec(), value.to_vec(), dest));
+		}
+
+
+		if col == Some(1) {
+			try!(batch.insert(vec![1, 2, 3], vec![4, 5, 6], dest));
+		}
+
+		batch.commit(dest)
+	}
+}
+
 #[test]
 fn one_simple_migration() {
 	let dir = RandomTempPath::create_dir();
@@ -189,3 +213,16 @@ fn is_migration_needed() {
 	assert!(manager.is_needed(1));
 	assert!(!manager.is_needed(2));
 }
+
+#[test]
+fn pre_columns() {
+	let mut manager = Manager::new(Config::default());
+	manager.add_migration(AddsColumn).unwrap();
+
+	let dir = RandomTempPath::create_dir();
+	let db_path = db_path(dir.as_path());
+
+	// this shouldn't fail to open the database even though it's one column
+	// short of the one before it.
+	manager.execute(&db_path, 0).unwrap();
+}