grassrootseconomics/openethereum
8
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Include total difficulty in CHTs and hide implementation details from consumers (#4428)

Browse Source 
* CHT builder and prover

* use CHT abstraction in provider

* hide CHT internals from header chain

* fix itertools conflict by updating all to 0.5

* cht proof checker, use it in on_demand
This commit is contained in:
Robert Habermeier
2017-02-06 17:21:35 +01:00
committed by Arkadiy Paronyan
parent 127baed385
commit 4172a5369c
12 changed files with 261 additions and 95 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
ethcore/light/src/client/header_chain.rs
View File

@@ -173,26 +173,34 @@ impl HeaderChain {
// produce next CHT root if it's time.
let earliest_era = *candidates.keys().next().expect("at least one era just created; qed");
if earliest_era + HISTORY + cht::SIZE <= number {
let mut values = Vec::with_capacity(cht::SIZE as usize);
{
let mut headers = self.headers.write();
for i in (0..cht::SIZE).map(|x| x + earliest_era) {
let cht_num = cht::block_to_cht_number(earliest_era)
.expect("fails only for number == 0; genesis never imported; qed");
debug_assert_eq!(cht_num as usize, self.cht_roots.lock().len());
let mut headers = self.headers.write();
let cht_root = {
let mut i = earliest_era;
// iterable function which removes the candidates as it goes
// along. this will only be called until the CHT is complete.
let iter = || {
let era_entry = candidates.remove(&i)
.expect("all eras are sequential with no gaps; qed");
i += 1;
for ancient in &era_entry.candidates {
headers.remove(&ancient.hash);
}
values.push((
::rlp::encode(&i).to_vec(),
::rlp::encode(&era_entry.canonical_hash).to_vec(),
));
}
}
let canon = &era_entry.candidates[0];
(canon.hash, canon.total_difficulty)
};
cht::compute_root(cht_num, ::itertools::repeat_call(iter))
.expect("fails only when too few items; this is checked; qed")
};
let cht_root = ::util::triehash::trie_root(values);
debug!(target: "chain", "Produced CHT {} root: {:?}", (earliest_era - 1) % cht::SIZE, cht_root);
debug!(target: "chain", "Produced CHT {} root: {:?}", cht_num, cht_root);
self.cht_roots.lock().push(cht_root);
}