go-ethereum/core/vm_env.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
4.4 KiB
Go

// Copyright 2014 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 core
import (
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/state"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/core/vm"
)
// GetHashFn returns a function for which the VM env can query block hashes through
// up to the limit defined by the Yellow Paper and uses the given block chain
// to query for information.
func GetHashFn(ref common.Hash, chain *BlockChain) func(n uint64) common.Hash {
return func(n uint64) common.Hash {
for block := chain.GetBlockByHash(ref); block != nil; block = chain.GetBlock(block.ParentHash(), block.NumberU64()-1) {
if block.NumberU64() == n {
return block.Hash()
}
}
return common.Hash{}
}
}
type VMEnv struct {
chainConfig *ChainConfig // Chain configuration
state *state.StateDB // State to use for executing
evm *vm.EVM // The Ethereum Virtual Machine
depth int // Current execution depth
msg Message // Message appliod
header *types.Header // Header information
chain *BlockChain // Blockchain handle
getHashFn func(uint64) common.Hash // getHashFn callback is used to retrieve block hashes
}
func NewEnv(state *state.StateDB, chainConfig *ChainConfig, chain *BlockChain, msg Message, header *types.Header, cfg vm.Config) *VMEnv {
env := &VMEnv{
chainConfig: chainConfig,
chain: chain,
state: state,
header: header,
msg: msg,
getHashFn: GetHashFn(header.ParentHash, chain),
}
env.evm = vm.New(env, cfg)
return env
}
func (self *VMEnv) RuleSet() vm.RuleSet { return self.chainConfig }
func (self *VMEnv) Vm() vm.Vm { return self.evm }
func (self *VMEnv) Origin() common.Address { f, _ := self.msg.From(); return f }
func (self *VMEnv) BlockNumber() *big.Int { return self.header.Number }
func (self *VMEnv) Coinbase() common.Address { return self.header.Coinbase }
func (self *VMEnv) Time() *big.Int { return self.header.Time }
func (self *VMEnv) Difficulty() *big.Int { return self.header.Difficulty }
func (self *VMEnv) GasLimit() *big.Int { return self.header.GasLimit }
func (self *VMEnv) Value() *big.Int { return self.msg.Value() }
func (self *VMEnv) Db() vm.Database { return self.state }
func (self *VMEnv) Depth() int { return self.depth }
func (self *VMEnv) SetDepth(i int) { self.depth = i }
func (self *VMEnv) GetHash(n uint64) common.Hash {
return self.getHashFn(n)
}
func (self *VMEnv) AddLog(log *vm.Log) {
self.state.AddLog(log)
}
func (self *VMEnv) CanTransfer(from common.Address, balance *big.Int) bool {
return self.state.GetBalance(from).Cmp(balance) >= 0
}
func (self *VMEnv) SnapshotDatabase() int {
return self.state.Snapshot()
}
func (self *VMEnv) RevertToSnapshot(snapshot int) {
self.state.RevertToSnapshot(snapshot)
}
func (self *VMEnv) Transfer(from, to vm.Account, amount *big.Int) {
Transfer(from, to, amount)
}
func (self *VMEnv) Call(me vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
return Call(self, me, addr, data, gas, price, value)
}
func (self *VMEnv) CallCode(me vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
return CallCode(self, me, addr, data, gas, price, value)
}
func (self *VMEnv) DelegateCall(me vm.ContractRef, addr common.Address, data []byte, gas, price *big.Int) ([]byte, error) {
return DelegateCall(self, me, addr, data, gas, price)
}
func (self *VMEnv) Create(me vm.ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error) {
return Create(self, me, data, gas, price, value)
}