120 lines
3.4 KiB
Rust
120 lines
3.4 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/>.
|
|
|
|
use hash::H256;
|
|
use sha3::Hashable;
|
|
use hashdb::HashDB;
|
|
use super::{TrieDB, Trie, TrieDBIterator, TrieItem, TrieIterator, Query};
|
|
|
|
/// A `Trie` implementation which hashes keys and uses a generic `HashDB` backing database.
|
|
/// Additionaly it stores inserted hash-key mappings for later retrieval.
|
|
///
|
|
/// Use it as a `Trie` or `TrieMut` trait object.
|
|
pub struct FatDB<'db> {
|
|
raw: TrieDB<'db>,
|
|
}
|
|
|
|
impl<'db> FatDB<'db> {
|
|
/// Create a new trie with the backing database `db` and empty `root`
|
|
/// Initialise to the state entailed by the genesis block.
|
|
/// This guarantees the trie is built correctly.
|
|
pub fn new(db: &'db HashDB, root: &'db H256) -> super::Result<Self> {
|
|
let fatdb = FatDB {
|
|
raw: TrieDB::new(db, root)?
|
|
};
|
|
|
|
Ok(fatdb)
|
|
}
|
|
|
|
/// Get the backing database.
|
|
pub fn db(&self) -> &HashDB {
|
|
self.raw.db()
|
|
}
|
|
}
|
|
|
|
impl<'db> Trie for FatDB<'db> {
|
|
fn iter<'a>(&'a self) -> super::Result<Box<TrieIterator<Item = TrieItem> + 'a>> {
|
|
FatDBIterator::new(&self.raw).map(|iter| Box::new(iter) as Box<_>)
|
|
}
|
|
|
|
fn root(&self) -> &H256 {
|
|
self.raw.root()
|
|
}
|
|
|
|
fn contains(&self, key: &[u8]) -> super::Result<bool> {
|
|
self.raw.contains(&key.sha3())
|
|
}
|
|
|
|
fn get_with<'a, 'key, Q: Query>(&'a self, key: &'key [u8], query: Q) -> super::Result<Option<Q::Item>>
|
|
where 'a: 'key
|
|
{
|
|
self.raw.get_with(&key.sha3(), query)
|
|
}
|
|
}
|
|
|
|
/// Itarator over inserted pairs of key values.
|
|
pub struct FatDBIterator<'db> {
|
|
trie_iterator: TrieDBIterator<'db>,
|
|
trie: &'db TrieDB<'db>,
|
|
}
|
|
|
|
impl<'db> FatDBIterator<'db> {
|
|
/// Creates new iterator.
|
|
pub fn new(trie: &'db TrieDB) -> super::Result<Self> {
|
|
Ok(FatDBIterator {
|
|
trie_iterator: TrieDBIterator::new(trie)?,
|
|
trie: trie,
|
|
})
|
|
}
|
|
}
|
|
|
|
impl<'db> TrieIterator for FatDBIterator<'db> {
|
|
fn seek(&mut self, key: &[u8]) -> super::Result<()> {
|
|
self.trie_iterator.seek(&key.sha3())
|
|
}
|
|
}
|
|
|
|
impl<'db> Iterator for FatDBIterator<'db> {
|
|
type Item = TrieItem<'db>;
|
|
|
|
fn next(&mut self) -> Option<Self::Item> {
|
|
self.trie_iterator.next()
|
|
.map(|res|
|
|
res.map(|(hash, value)| {
|
|
let aux_hash = hash.sha3();
|
|
(self.trie.db().get(&aux_hash).expect("Missing fatdb hash").into_vec(), value)
|
|
})
|
|
)
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn fatdb_to_trie() {
|
|
use memorydb::MemoryDB;
|
|
use hashdb::DBValue;
|
|
use trie::{FatDBMut, TrieMut};
|
|
|
|
let mut memdb = MemoryDB::new();
|
|
let mut root = H256::default();
|
|
{
|
|
let mut t = FatDBMut::new(&mut memdb, &mut root);
|
|
t.insert(&[0x01u8, 0x23], &[0x01u8, 0x23]).unwrap();
|
|
}
|
|
let t = FatDB::new(&memdb, &root).unwrap();
|
|
assert_eq!(t.get(&[0x01u8, 0x23]).unwrap().unwrap(), DBValue::from_slice(&[0x01u8, 0x23]));
|
|
assert_eq!(t.iter().unwrap().map(Result::unwrap).collect::<Vec<_>>(), vec![(vec![0x01u8, 0x23], DBValue::from_slice(&[0x01u8, 0x23] as &[u8]))]);
|
|
}
|