Merge pull request #3527 from ethcore/client-provider

LES Part 2

ethcore/light/Cargo.toml

@@ -5,12 +5,17 @@ license = "GPL-3.0"
 name = "ethcore-light"
 version = "1.5.0"
 authors = ["Ethcore <admin@ethcore.io>"]
+build = "build.rs"
+
+[build-dependencies]
+"ethcore-ipc-codegen" = { path = "../../ipc/codegen" }
 
 [dependencies]
 log = "0.3"
 ethcore = { path = ".." }
 ethcore-util = { path = "../../util" }
 ethcore-network = { path = "../../util/network" }
 ethcore-io = { path = "../../util/io" }
+ethcore-ipc = { path = "../../ipc/rpc" }
 rlp = { path = "../../util/rlp" }
 time = "0.1"

ethcore/light/build.rs

@@ -0,0 +1,21 @@
+// 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/>.
+
+extern crate ethcore_ipc_codegen;
+
+fn main() {
+	ethcore_ipc_codegen::derive_binary("src/types/mod.rs.in").unwrap();
+}

ethcore/light/src/client.rs

@@ -101,7 +101,7 @@ impl Provider for Client {
 		Vec::new()
 	}
 
-	fn code(&self, _req: request::ContractCodes) -> Vec<Bytes> {
+	fn contract_code(&self, _req: request::ContractCodes) -> Vec<Bytes> {
 		Vec::new()
 	}
 

ethcore/light/src/lib.rs

@@ -28,20 +28,25 @@
 //! It starts by performing a header-only sync, verifying random samples
 //! of members of the chain to varying degrees.
 
-// TODO: remove when integrating with parity.
+// TODO: remove when integrating with the rest of parity.
 #![allow(dead_code)]
 
 pub mod client;
 pub mod net;
 pub mod provider;
-pub mod request;
 
+mod types;
+
+pub use self::provider::Provider;
+pub use types::les_request as request;
+
+#[macro_use]
+extern crate log;
+
+extern crate ethcore;
 extern crate ethcore_util as util;
 extern crate ethcore_network as network;
 extern crate ethcore_io as io;
-extern crate ethcore;
+extern crate ethcore_ipc as ipc;
 extern crate rlp;
-extern crate time;
-
-#[macro_use]
-extern crate log;
+extern crate time;

ethcore/light/src/net/buffer_flow.rs

@@ -206,6 +206,39 @@ impl FlowParams {
 		cost.0 + (amount * cost.1)
 	}
 
+	/// Compute the maximum number of costs of a specific kind which can be made 
+	/// with the given buffer.
+	/// Saturates at `usize::max()`. This is not a problem in practice because
+	/// this amount of requests is already prohibitively large.
+	pub fn max_amount(&self, buffer: &Buffer, kind: request::Kind) -> usize {
+		use util::Uint;
+		use std::usize;
+
+		let cost = match kind {
+			request::Kind::Headers => &self.costs.headers,
+			request::Kind::Bodies => &self.costs.bodies,
+			request::Kind::Receipts => &self.costs.receipts,
+			request::Kind::StateProofs => &self.costs.state_proofs,
+			request::Kind::Codes => &self.costs.contract_codes,
+			request::Kind::HeaderProofs => &self.costs.header_proofs,
+		};
+
+		let start = buffer.current();
+
+		if start <= cost.0 {
+			return 0;
+		} else if cost.1 == U256::zero() {
+			return usize::MAX;
+		}
+
+		let max = (start - cost.0) / cost.1;
+		if max >= usize::MAX.into() {
+			usize::MAX
+		} else {
+			max.as_u64() as usize
+		}
+	}
+
 	/// Create initial buffer parameter.
 	pub fn create_buffer(&self) -> Buffer {
 		Buffer {
@@ -228,6 +261,16 @@ impl FlowParams {
 
 		buf.estimate = ::std::cmp::min(self.limit, buf.estimate + (elapsed * self.recharge));
 	}
+
+	/// Refund some buffer which was previously deducted.
+	/// Does not update the recharge timestamp.
+	pub fn refund(&self, buf: &mut Buffer, refund_amount: U256) {
+		buf.estimate = buf.estimate + refund_amount;
+
+		if buf.estimate > self.limit {
+			buf.estimate = self.limit
+		}
+	}
 }
 
 #[cfg(test)]

ethcore/light/src/net/error.rs

@@ -52,6 +52,8 @@ pub enum Error {
 	UnexpectedHandshake,
 	/// Peer on wrong network (wrong NetworkId or genesis hash)
 	WrongNetwork,
+	/// Unknown peer.
+	UnknownPeer,
 }
 
 impl Error {
@@ -64,6 +66,7 @@ impl Error {
 			Error::UnrecognizedPacket(_) => Punishment::Disconnect,
 			Error::UnexpectedHandshake => Punishment::Disconnect,
 			Error::WrongNetwork => Punishment::Disable,
+			Error::UnknownPeer => Punishment::Disconnect,
 		}
 	}
 }
@@ -89,6 +92,7 @@ impl fmt::Display for Error {
 			Error::UnrecognizedPacket(code) => write!(f, "Unrecognized packet: 0x{:x}", code),
 			Error::UnexpectedHandshake => write!(f, "Unexpected handshake"),
 			Error::WrongNetwork => write!(f, "Wrong network"),
+			Error::UnknownPeer => write!(f, "unknown peer"),
 		}
 	}
 }