// 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 .
//! Block header.
use util::*;
use basic_types::*;
use time::now_utc;
/// Type for Block number
pub type BlockNumber = u64;
/// A block header.
///
/// Reflects the specific RLP fields of a block in the chain with additional room for the seal
/// which is non-specific.
///
/// Doesn't do all that much on its own.
#[derive(Debug, Clone, Eq)]
pub struct Header {
// TODO: make all private.
/// Parent hash.
pub parent_hash: H256,
/// Block timestamp.
pub timestamp: u64,
/// Block number.
pub number: BlockNumber,
/// Block author.
pub author: Address,
/// Transactions root.
pub transactions_root: H256,
/// Block uncles hash.
pub uncles_hash: H256,
/// Block extra data.
pub extra_data: Bytes,
/// State root.
pub state_root: H256,
/// Block receipts root.
pub receipts_root: H256,
/// Block bloom.
pub log_bloom: LogBloom,
/// Gas used for contracts execution.
pub gas_used: U256,
/// Block gas limit.
pub gas_limit: U256,
/// Block difficulty.
pub difficulty: U256,
/// Vector of post-RLP-encoded fields.
pub seal: Vec,
/// The memoized hash of the RLP representation *including* the seal fields.
pub hash: RefCell>,
/// The memoized hash of the RLP representation *without* the seal fields.
pub bare_hash: RefCell>,
}
impl PartialEq for Header {
fn eq(&self, c: &Header) -> bool {
self.parent_hash == c.parent_hash &&
self.timestamp == c.timestamp &&
self.number == c.number &&
self.author == c.author &&
self.transactions_root == c.transactions_root &&
self.uncles_hash == c.uncles_hash &&
self.extra_data == c.extra_data &&
self.state_root == c.state_root &&
self.receipts_root == c.receipts_root &&
self.log_bloom == c.log_bloom &&
self.gas_used == c.gas_used &&
self.gas_limit == c.gas_limit &&
self.difficulty == c.difficulty &&
self.seal == c.seal
}
}
impl Default for Header {
fn default() -> Self {
Header {
parent_hash: ZERO_H256.clone(),
timestamp: 0,
number: 0,
author: ZERO_ADDRESS.clone(),
transactions_root: SHA3_NULL_RLP,
uncles_hash: SHA3_EMPTY_LIST_RLP,
extra_data: vec![],
state_root: SHA3_NULL_RLP,
receipts_root: SHA3_NULL_RLP,
log_bloom: ZERO_LOGBLOOM.clone(),
gas_used: ZERO_U256,
gas_limit: ZERO_U256,
difficulty: ZERO_U256,
seal: vec![],
hash: RefCell::new(None),
bare_hash: RefCell::new(None),
}
}
}
impl Header {
/// Create a new, default-valued, header.
pub fn new() -> Self {
Self::default()
}
/// Get the parent_hash field of the header.
pub fn parent_hash(&self) -> &H256 { &self.parent_hash }
/// Get the timestamp field of the header.
pub fn timestamp(&self) -> u64 { self.timestamp }
/// Get the number field of the header.
pub fn number(&self) -> BlockNumber { self.number }
/// Get the author field of the header.
pub fn author(&self) -> &Address { &self.author }
/// Get the extra data field of the header.
pub fn extra_data(&self) -> &Bytes { &self.extra_data }
/// Get the state root field of the header.
pub fn state_root(&self) -> &H256 { &self.state_root }
/// Get the receipts root field of the header.
pub fn receipts_root(&self) -> &H256 { &self.receipts_root }
/// Get the gas limit field of the header.
pub fn gas_limit(&self) -> &U256 { &self.gas_limit }
/// Get the difficulty field of the header.
pub fn difficulty(&self) -> &U256 { &self.difficulty }
/// Get the seal field of the header.
pub fn seal(&self) -> &Vec { &self.seal }
// TODO: seal_at, set_seal_at &c.
/// Set the number field of the header.
pub fn set_parent_hash(&mut self, a: H256) { self.parent_hash = a; self.note_dirty(); }
/// Set the timestamp field of the header.
pub fn set_timestamp(&mut self, a: u64) { self.timestamp = a; self.note_dirty(); }
/// Set the timestamp field of the header to the current time.
pub fn set_timestamp_now(&mut self, but_later_than: u64) { self.timestamp = max(now_utc().to_timespec().sec as u64, but_later_than + 1); self.note_dirty(); }
/// Set the number field of the header.
pub fn set_number(&mut self, a: BlockNumber) { self.number = a; self.note_dirty(); }
/// Set the author field of the header.
pub fn set_author(&mut self, a: Address) { if a != self.author { self.author = a; self.note_dirty(); } }
/// Set the extra data field of the header.
pub fn set_extra_data(&mut self, a: Bytes) { if a != self.extra_data { self.extra_data = a; self.note_dirty(); } }
/// Set the gas used field of the header.
pub fn set_gas_used(&mut self, a: U256) { self.gas_used = a; self.note_dirty(); }
/// Set the gas limit field of the header.
pub fn set_gas_limit(&mut self, a: U256) { self.gas_limit = a; self.note_dirty(); }
/// Set the difficulty field of the header.
pub fn set_difficulty(&mut self, a: U256) { self.difficulty = a; self.note_dirty(); }
/// Set the seal field of the header.
pub fn set_seal(&mut self, a: Vec) { self.seal = a; self.note_dirty(); }
/// Get the hash of this header (sha3 of the RLP).
pub fn hash(&self) -> H256 {
let mut hash = self.hash.borrow_mut();
match &mut *hash {
&mut Some(ref h) => h.clone(),
hash @ &mut None => {
*hash = Some(self.rlp_sha3(Seal::With));
hash.as_ref().unwrap().clone()
}
}
}
/// Get the hash of the header excluding the seal
pub fn bare_hash(&self) -> H256 {
let mut hash = self.bare_hash.borrow_mut();
match &mut *hash {
&mut Some(ref h) => h.clone(),
hash @ &mut None => {
*hash = Some(self.rlp_sha3(Seal::Without));
hash.as_ref().unwrap().clone()
}
}
}
/// Note that some fields have changed. Resets the memoised hash.
pub fn note_dirty(&self) {
*self.hash.borrow_mut() = None;
*self.bare_hash.borrow_mut() = None;
}
// TODO: make these functions traity
/// Place this header into an RLP stream `s`, optionally `with_seal`.
pub fn stream_rlp(&self, s: &mut RlpStream, with_seal: Seal) {
s.begin_list(13 + match with_seal { Seal::With => self.seal.len(), _ => 0 });
s.append(&self.parent_hash);
s.append(&self.uncles_hash);
s.append(&self.author);
s.append(&self.state_root);
s.append(&self.transactions_root);
s.append(&self.receipts_root);
s.append(&self.log_bloom);
s.append(&self.difficulty);
s.append(&self.number);
s.append(&self.gas_limit);
s.append(&self.gas_used);
s.append(&self.timestamp);
s.append(&self.extra_data);
if let Seal::With = with_seal {
for b in &self.seal {
s.append_raw(&b, 1);
}
}
}
/// Get the RLP of this header, optionally `with_seal`.
pub fn rlp(&self, with_seal: Seal) -> Bytes {
let mut s = RlpStream::new();
self.stream_rlp(&mut s, with_seal);
s.out()
}
/// Get the SHA3 (Keccak) of this header, optionally `with_seal`.
pub fn rlp_sha3(&self, with_seal: Seal) -> H256 { self.rlp(with_seal).sha3() }
}
impl Decodable for Header {
fn decode(decoder: &D) -> Result where D: Decoder {
let r = decoder.as_rlp();
let mut blockheader = Header {
parent_hash: try!(r.val_at(0)),
uncles_hash: try!(r.val_at(1)),
author: try!(r.val_at(2)),
state_root: try!(r.val_at(3)),
transactions_root: try!(r.val_at(4)),
receipts_root: try!(r.val_at(5)),
log_bloom: try!(r.val_at(6)),
difficulty: try!(r.val_at(7)),
number: try!(r.val_at(8)),
gas_limit: try!(r.val_at(9)),
gas_used: try!(r.val_at(10)),
timestamp: try!(r.val_at(11)),
extra_data: try!(r.val_at(12)),
seal: vec![],
hash: RefCell::new(Some(r.as_raw().sha3())),
bare_hash: RefCell::new(None),
};
for i in 13..r.item_count() {
blockheader.seal.push(try!(r.at(i)).as_raw().to_vec())
}
Ok(blockheader)
}
}
impl Encodable for Header {
fn rlp_append(&self, s: &mut RlpStream) {
self.stream_rlp(s, Seal::With);
}
}
#[cfg(test)]
mod tests {
use rustc_serialize::hex::FromHex;
use util::rlp::{decode, encode};
use super::Header;
#[test]
fn test_header_seal_fields() {
// that's rlp of block header created with ethash engine.
let header_rlp = "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".from_hex().unwrap();
let mix_hash = "a0a0349d8c3df71f1a48a9df7d03fd5f14aeee7d91332c009ecaff0a71ead405bd".from_hex().unwrap();
let nonce = "88ab4e252a7e8c2a23".from_hex().unwrap();
let header: Header = decode(&header_rlp);
let seal_fields = header.seal;
assert_eq!(seal_fields.len(), 2);
assert_eq!(seal_fields[0], mix_hash);
assert_eq!(seal_fields[1], nonce);
}
#[test]
fn decode_and_encode_header() {
// that's rlp of block header created with ethash engine.
let header_rlp = "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".from_hex().unwrap();
let header: Header = decode(&header_rlp);
let encoded_header = encode(&header).to_vec();
assert_eq!(header_rlp, encoded_header);
}
}