go-ethereum/core/vm_env.go
Jeffrey Wilcke 342ae7ce7d core, core/vm, tests: changed the initialisation behaviour of the EVM
The EVM was previously initialised and created for every CALL, CALLCODE,
DELEGATECALL and CREATE. This PR changes this behaviour so that the same
EVM can be used through the session and beyond as long as the
Environment sticks around.
2016-03-23 00:04:00 +01:00

128 lines
4.3 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.GetBlock(ref); block != nil; block = chain.GetBlock(block.ParentHash()) {
if block.NumberU64() == n {
return block.Hash()
}
}
return common.Hash{}
}
}
type VMEnv struct {
state *state.StateDB
header *types.Header
msg Message
depth int
chain *BlockChain
typ vm.Type
getHashFn func(uint64) common.Hash
// structured logging
logs []vm.StructLog
evm *vm.Vm
}
func NewEnv(state *state.StateDB, chain *BlockChain, msg Message, header *types.Header) *VMEnv {
env := &VMEnv{
chain: chain,
state: state,
header: header,
msg: msg,
typ: vm.StdVmTy,
getHashFn: GetHashFn(header.ParentHash, chain),
}
env.evm = vm.EVM(env)
return env
}
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) VmType() vm.Type { return self.typ }
func (self *VMEnv) SetVmType(t vm.Type) { self.typ = t }
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) MakeSnapshot() vm.Database {
return self.state.Copy()
}
func (self *VMEnv) SetSnapshot(copy vm.Database) {
self.state.Set(copy.(*state.StateDB))
}
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)
}
func (self *VMEnv) StructLogs() []vm.StructLog {
return self.logs
}
func (self *VMEnv) AddStructLog(log vm.StructLog) {
self.logs = append(self.logs, log)
}