1 files changed, 86 insertions, 0 deletions
diff --git a/core/state/snapshot/account.go b/core/state/snapshot/account.go
new file mode 100644
index 0000000..b92e942
--- /dev/null
+++ b/core/state/snapshot/account.go
@@ -0,0 +1,86 @@
+// Copyright 2019 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library 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 Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package snapshot
+
+import (
+	"bytes"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/rlp"
+)
+
+// Account is a modified version of a state.Account, where the root is replaced
+// with a byte slice. This format can be used to represent full-consensus format
+// or slim-snapshot format which replaces the empty root and code hash as nil
+// byte slice.
+type Account struct {
+	Nonce    uint64
+	Balance  *big.Int
+	Root     []byte
+	CodeHash []byte
+}
+
+// SlimAccount converts a state.Account content into a slim snapshot account
+func SlimAccount(nonce uint64, balance *big.Int, root common.Hash, codehash []byte) Account {
+	slim := Account{
+		Nonce:   nonce,
+		Balance: balance,
+	}
+	if root != emptyRoot {
+		slim.Root = root[:]
+	}
+	if !bytes.Equal(codehash, emptyCode[:]) {
+		slim.CodeHash = codehash
+	}
+	return slim
+}
+
+// SlimAccountRLP converts a state.Account content into a slim snapshot
+// version RLP encoded.
+func SlimAccountRLP(nonce uint64, balance *big.Int, root common.Hash, codehash []byte) []byte {
+	data, err := rlp.EncodeToBytes(SlimAccount(nonce, balance, root, codehash))
+	if err != nil {
+		panic(err)
+	}
+	return data
+}
+
+// FullAccount decodes the data on the 'slim RLP' format and return
+// the consensus format account.
+func FullAccount(data []byte) (Account, error) {
+	var account Account
+	if err := rlp.DecodeBytes(data, &account); err != nil {
+		return Account{}, err
+	}
+	if len(account.Root) == 0 {
+		account.Root = emptyRoot[:]
+	}
+	if len(account.CodeHash) == 0 {
+		account.CodeHash = emptyCode[:]
+	}
+	return account, nil
+}
+
+// FullAccountRLP converts data on the 'slim RLP' format into the full RLP-format.
+func FullAccountRLP(data []byte) ([]byte, error) {
+	account, err := FullAccount(data)
+	if err != nil {
+		return nil, err
+	}
+	return rlp.EncodeToBytes(account)
+}