openethereum/ethcore/vm/src/env_info.rs
2017-09-04 16:36:49 +02:00

112 lines
3.2 KiB
Rust

// Copyright 2015-2017 Parity Technologies (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/>.
//! Environment information for transaction execution.
use std::cmp;
use std::sync::Arc;
use hash::keccak;
use bigint::hash::H256;
use bigint::prelude::U256;
use util::Address;
use types::BlockNumber;
use ethjson;
/// Simple vector of hashes, should be at most 256 items large, can be smaller if being used
/// for a block whose number is less than 257.
pub type LastHashes = Vec<H256>;
/// Information concerning the execution environment for a message-call/contract-creation.
#[derive(Debug, Clone)]
pub struct EnvInfo {
/// The block number.
pub number: BlockNumber,
/// The block author.
pub author: Address,
/// The block timestamp.
pub timestamp: u64,
/// The block difficulty.
pub difficulty: U256,
/// The block gas limit.
pub gas_limit: U256,
/// The last 256 block hashes.
pub last_hashes: Arc<LastHashes>,
/// The gas used.
pub gas_used: U256,
}
impl Default for EnvInfo {
fn default() -> Self {
EnvInfo {
number: 0,
author: Address::default(),
timestamp: 0,
difficulty: 0.into(),
gas_limit: 0.into(),
last_hashes: Arc::new(vec![]),
gas_used: 0.into(),
}
}
}
impl From<ethjson::vm::Env> for EnvInfo {
fn from(e: ethjson::vm::Env) -> Self {
let number = e.number.into();
EnvInfo {
number: number,
author: e.author.into(),
difficulty: e.difficulty.into(),
gas_limit: e.gas_limit.into(),
timestamp: e.timestamp.into(),
last_hashes: Arc::new((1..cmp::min(number + 1, 257)).map(|i| keccak(format!("{}", number - i).as_bytes())).collect()),
gas_used: U256::default(),
}
}
}
#[cfg(test)]
mod tests {
use std::str::FromStr;
use super::*;
use bigint::prelude::U256;
use util::Address;
use ethjson;
#[test]
fn it_serializes_from_json() {
let env_info = EnvInfo::from(ethjson::vm::Env {
author: ethjson::hash::Address(Address::from_str("000000f00000000f000000000000f00000000f00").unwrap()),
number: ethjson::uint::Uint(U256::from(1_112_339)),
difficulty: ethjson::uint::Uint(U256::from(50_000)),
gas_limit: ethjson::uint::Uint(U256::from(40_000)),
timestamp: ethjson::uint::Uint(U256::from(1_100))
});
assert_eq!(env_info.number, 1112339);
assert_eq!(env_info.author, Address::from_str("000000f00000000f000000000000f00000000f00").unwrap());
assert_eq!(env_info.gas_limit, 40000.into());
assert_eq!(env_info.difficulty, 50000.into());
assert_eq!(env_info.gas_used, 0.into());
}
#[test]
fn it_can_be_created_as_default() {
let default_env_info = EnvInfo::default();
assert_eq!(default_env_info.difficulty, 0.into());
}
}