From 755ee95326945443cf342e3380261a1a98d8bd30 Mon Sep 17 00:00:00 2001
From: arkpar <arkadiy.paronyan@gmail.com>
Date: Fri, 5 Feb 2016 01:49:17 +0100
Subject: [PATCH] Cleanup

---
 ethcore/src/account_db.rs | 117 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 117 insertions(+)
 create mode 100644 ethcore/src/account_db.rs

diff --git a/ethcore/src/account_db.rs b/ethcore/src/account_db.rs
new file mode 100644
index 000000000..7a07778f0
--- /dev/null
+++ b/ethcore/src/account_db.rs
@@ -0,0 +1,117 @@
+//! DB backend wrapper for Account trie
+use util::*;
+
+static NULL_RLP_STATIC: [u8; 1] = [0x80; 1];
+
+// TODO: introduce HashDBMut?
+/// DB backend wrapper for Account trie
+/// Transforms trie node keys for the database
+pub struct AccountDB<'db> {
+	db: &'db HashDB,
+	address: H256,
+}
+
+#[inline]
+fn combine_key<'a>(address: &'a H256, key: &'a H256) -> H256 {
+	address ^ key
+}
+
+impl<'db> AccountDB<'db> {
+	pub fn new(db: &'db HashDB, address: &Address) -> AccountDB<'db> {
+		AccountDB {
+			db: db,
+			address: x!(address.clone()),
+		}
+	}
+}
+
+impl<'db> HashDB for AccountDB<'db>{
+	fn keys(&self) -> HashMap<H256, i32> {
+		unimplemented!()
+	}
+
+	fn lookup(&self, key: &H256) -> Option<&[u8]> {
+		if key == &SHA3_NULL_RLP {
+			return Some(&NULL_RLP_STATIC);
+		}
+		self.db.lookup(&combine_key(&self.address, key))
+	}
+
+	fn exists(&self, key: &H256) -> bool {
+		if key == &SHA3_NULL_RLP {
+			return true;
+		}
+		self.db.exists(&combine_key(&self.address, key))
+	}
+
+	fn insert(&mut self, _value: &[u8]) -> H256 {
+		unimplemented!()
+	}
+
+	fn emplace(&mut self, _key: H256, _value: Bytes) {
+		unimplemented!()
+	}
+
+	fn kill(&mut self, _key: &H256) {
+		unimplemented!()
+	}
+}
+
+/// DB backend wrapper for Account trie
+pub struct AccountDBMut<'db> {
+	db: &'db mut HashDB,
+	address: H256,
+}
+
+impl<'db> AccountDBMut<'db> {
+	pub fn new(db: &'db mut HashDB, address: &Address) -> AccountDBMut<'db> {
+		AccountDBMut {
+			db: db,
+			address: x!(address.clone()),
+		}
+	}
+
+	#[allow(dead_code)]
+	pub fn immutable(&'db self) -> AccountDB<'db> {
+		AccountDB { db: self.db, address: self.address.clone() }
+	}
+}
+
+impl<'db> HashDB for AccountDBMut<'db>{
+	fn keys(&self) -> HashMap<H256, i32> {
+		unimplemented!()
+	}
+
+	fn lookup(&self, key: &H256) -> Option<&[u8]> {
+		if key == &SHA3_NULL_RLP {
+			return Some(&NULL_RLP_STATIC);
+		}
+		self.db.lookup(&combine_key(&self.address, key))
+	}
+
+	fn exists(&self, key: &H256) -> bool {
+		if key == &SHA3_NULL_RLP {
+			return true;
+		}
+		self.db.exists(&combine_key(&self.address, key))
+	}
+
+	fn insert(&mut self, value: &[u8]) -> H256 {
+		let k = value.sha3();
+		let ak = combine_key(&self.address, &k);
+		self.db.emplace(ak, value.to_vec());
+		k
+	}
+
+	fn emplace(&mut self, key: H256, value: Bytes) {
+		let key = combine_key(&self.address, &key);
+		self.db.emplace(key, value.to_vec())
+	}
+
+	fn kill(&mut self, key: &H256) {
+		let key = combine_key(&self.address, key);
+		self.db.kill(&key)
+	}
+}
+
+