Merge pull request #3994 from ethcore/remove-dead-journal

remove node journal: dead code

util/src/trie/journal.rs

@@ -1,103 +0,0 @@
-// Copyright 2015, 2016 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 std::default::Default;
-use sha3::*;
-use hash::H256;
-use bytes::*;
-use rlp::*;
-use hashdb::*;
-
-/// Type of operation for the backing database - either a new node or a node deletion.
-#[derive(Debug)]
-enum Operation {
-	New(H256, DBValue),
-	Delete(H256),
-}
-
-/// How many insertions and removals were done in an `apply` operation.
-pub struct Score {
-	/// Number of insertions.
-	pub inserts: usize,
-	/// Number of removals.
-	pub removes: usize,
-}
-
-/// A journal of operations on the backing database.
-#[derive(Debug)]
-pub struct Journal (Vec<Operation>);
-
-impl Default for Journal {
-	fn default() -> Self {
-		Journal::new()
-	}
-}
-
-impl Journal {
-	/// Create a new, empty, object.
-	pub fn new() -> Journal { Journal(vec![]) }
-
-	/// Given the RLP that encodes a node, append a reference to that node `out` and leave `journal`
-	/// such that the reference is valid, once applied.
-	pub fn new_node(&mut self, rlp: DBValue, out: &mut RlpStream) {
-		if rlp.len() >= 32 {
-			let rlp_sha3 = rlp.sha3();
-
-			trace!("new_node: reference node {:?} => {:?}", rlp_sha3, &*rlp);
-			out.append(&rlp_sha3);
-			self.0.push(Operation::New(rlp_sha3, rlp));
-		}
-		else {
-			trace!("new_node: inline node {:?}", &*rlp);
-			out.append_raw(&rlp, 1);
-		}
-	}
-
-	/// Given the RLP that encodes a now-unused node, leave `journal` in such a state that it is noted.
-	pub fn delete_node_sha3(&mut self, old_sha3: H256) {
-		trace!("delete_node:  {:?}", old_sha3);
-		self.0.push(Operation::Delete(old_sha3));
-	}
-
-	/// Register an RLP-encoded node for deletion (given a slice), if it needs to be deleted.
-	pub fn delete_node(&mut self, old: &[u8]) {
-		let r = Rlp::new(old);
-		if r.is_data() && r.size() == 32 {
-			self.delete_node_sha3(r.as_val());
-		}
-	}
-
-	/// Apply this journal to the HashDB `db` and return the number of insertions and removals done.
-	pub fn apply(self, db: &mut HashDB) -> Score {
-		trace!("applying {:?} changes", self.0.len());
-		let mut ret = Score{inserts: 0, removes: 0};
-		for d in self.0 {
-			match d {
-				Operation::Delete(h) => {
-					trace!("TrieDBMut::apply --- {:?}", &h);
-					db.remove(&h);
-					ret.removes += 1;
-				},
-				Operation::New(h, d) => {
-					trace!("TrieDBMut::apply +++ {:?} -> {:?}", &h, d.pretty());
-					db.emplace(h, d);
-					ret.inserts += 1;
-				}
-			}
-		}
-		ret
-	}
-}

util/src/trie/mod.rs

@@ -22,8 +22,6 @@ use hashdb::{HashDB, DBValue};
 
 /// Export the standardmap module.
 pub mod standardmap;
-/// Export the journal module.
-pub mod journal;
 /// Export the node module.
 pub mod node;
 /// Export the triedb module.

util/src/trie/node.rs

@@ -18,7 +18,6 @@ use elastic_array::ElasticArray36;
 use nibbleslice::*;
 use bytes::*;
 use rlp::*;
-use super::journal::*;
 use hashdb::DBValue;
 
 /// Partial node key type.
@@ -123,44 +122,4 @@ impl Node {
 			}
 		}
 	}
-
-	/// Encode the node, adding it to `journal` if necessary and return the RLP valid for
-	/// insertion into a parent node.
-	pub fn encoded_and_added(&self, journal: &mut Journal) -> DBValue {
-		let mut stream = RlpStream::new();
-		match *self {
-			Node::Leaf(ref slice, ref value) => {
-				stream.begin_list(2);
-				stream.append(&&**slice);
-				stream.append(&&**value);
-			},
-			Node::Extension(ref slice, ref raw_rlp) => {
-				stream.begin_list(2);
-				stream.append(&&**slice);
-				stream.append_raw(&&**raw_rlp, 1);
-			},
-			Node::Branch(ref nodes, ref value) => {
-				stream.begin_list(17);
-				for i in 0..16 {
-					stream.append_raw(&*nodes[i], 1);
-				}
-				match *value {
-					Some(ref n) => { stream.append(&&**n); },
-					None => { stream.append_empty_data(); },
-				}
-			},
-			Node::Empty => {
-				stream.append_empty_data();
-			}
-		}
-		let node = DBValue::from_slice(stream.as_raw());
-		match node.len() {
-			0 ... 31 => node,
-			_ => {
-				let mut stream = RlpStream::new();
-				journal.new_node(node, &mut stream);
-				DBValue::from_slice(stream.as_raw())
-			}
-		}
-	}
 }