plugeth/core/state/journal.go
Felix Lange 1f1ea18b54 core/state: implement reverts by journaling all changes
This commit replaces the deep-copy based state revert mechanism with a
linear complexity journal. This commit also hides several internal
StateDB methods to limit the number of ways in which calling code can
use the journal incorrectly.

As usual consultation and bug fixes to the initial implementation were
provided by @karalabe, @obscuren and @Arachnid. Thank you!
2016-10-06 15:32:16 +02:00

118 lines
2.7 KiB
Go

// Copyright 2016 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 state
import (
"math/big"
"github.com/ethereum/go-ethereum/common"
)
type journalEntry interface {
undo(*StateDB)
}
type journal []journalEntry
type (
// Changes to the account trie.
createObjectChange struct {
account *common.Address
}
resetObjectChange struct {
prev *StateObject
}
deleteAccountChange struct {
account *common.Address
prev bool // whether account had already suicided
prevbalance *big.Int
}
// Changes to individual accounts.
balanceChange struct {
account *common.Address
prev *big.Int
}
nonceChange struct {
account *common.Address
prev uint64
}
storageChange struct {
account *common.Address
key, prevalue common.Hash
}
codeChange struct {
account *common.Address
prevcode, prevhash []byte
}
// Changes to other state values.
refundChange struct {
prev *big.Int
}
addLogChange struct {
txhash common.Hash
}
)
func (ch createObjectChange) undo(s *StateDB) {
s.GetStateObject(*ch.account).deleted = true
delete(s.stateObjects, *ch.account)
delete(s.stateObjectsDirty, *ch.account)
}
func (ch resetObjectChange) undo(s *StateDB) {
s.setStateObject(ch.prev)
}
func (ch deleteAccountChange) undo(s *StateDB) {
obj := s.GetStateObject(*ch.account)
if obj != nil {
obj.remove = ch.prev
obj.setBalance(ch.prevbalance)
}
}
func (ch balanceChange) undo(s *StateDB) {
s.GetStateObject(*ch.account).setBalance(ch.prev)
}
func (ch nonceChange) undo(s *StateDB) {
s.GetStateObject(*ch.account).setNonce(ch.prev)
}
func (ch codeChange) undo(s *StateDB) {
s.GetStateObject(*ch.account).setCode(common.BytesToHash(ch.prevhash), ch.prevcode)
}
func (ch storageChange) undo(s *StateDB) {
s.GetStateObject(*ch.account).setState(ch.key, ch.prevalue)
}
func (ch refundChange) undo(s *StateDB) {
s.refund = ch.prev
}
func (ch addLogChange) undo(s *StateDB) {
logs := s.logs[ch.txhash]
if len(logs) == 1 {
delete(s.logs, ch.txhash)
} else {
s.logs[ch.txhash] = logs[:len(logs)-1]
}
}