go-ethereum/core/execution.go
2015-06-10 10:59:44 +02:00

102 lines
2.6 KiB
Go

package core
import (
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/state"
"github.com/ethereum/go-ethereum/core/vm"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/params"
)
type Execution struct {
env vm.Environment
address *common.Address
input []byte
evm vm.VirtualMachine
Gas, price, value *big.Int
}
func NewExecution(env vm.Environment, address *common.Address, input []byte, gas, gasPrice, value *big.Int) *Execution {
exe := &Execution{env: env, address: address, input: input, Gas: gas, price: gasPrice, value: value}
exe.evm = vm.NewVm(env)
return exe
}
func (self *Execution) Call(codeAddr common.Address, caller vm.ContextRef) ([]byte, error) {
// Retrieve the executing code
code := self.env.State().GetCode(codeAddr)
return self.exec(&codeAddr, code, caller)
}
func (self *Execution) Create(caller vm.ContextRef) (ret []byte, err error, account *state.StateObject) {
// Input must be nil for create
code := self.input
self.input = nil
ret, err = self.exec(nil, code, caller)
// Here we get an error if we run into maximum stack depth,
// See: https://github.com/ethereum/yellowpaper/pull/131
// and YP definitions for CREATE instruction
if err != nil {
return nil, err, nil
}
account = self.env.State().GetStateObject(*self.address)
return
}
func (self *Execution) exec(contextAddr *common.Address, code []byte, caller vm.ContextRef) (ret []byte, err error) {
env := self.env
evm := self.evm
if env.Depth() > int(params.CallCreateDepth.Int64()) {
caller.ReturnGas(self.Gas, self.price)
return nil, vm.DepthError{}
}
vsnapshot := env.State().Copy()
var createAccount bool
if self.address == nil {
// Generate a new address
nonce := env.State().GetNonce(caller.Address())
env.State().SetNonce(caller.Address(), nonce+1)
addr := crypto.CreateAddress(caller.Address(), nonce)
self.address = &addr
createAccount = true
}
snapshot := env.State().Copy()
var (
from = env.State().GetStateObject(caller.Address())
to *state.StateObject
)
if createAccount {
to = env.State().CreateAccount(*self.address)
} else {
to = env.State().GetOrNewStateObject(*self.address)
}
err = env.Transfer(from, to, self.value)
if err != nil {
env.State().Set(vsnapshot)
caller.ReturnGas(self.Gas, self.price)
return nil, ValueTransferErr("insufficient funds to transfer value. Req %v, has %v", self.value, from.Balance())
}
context := vm.NewContext(caller, to, self.value, self.Gas, self.price)
context.SetCallCode(contextAddr, code)
ret, err = evm.Run(context, self.input)
if err != nil {
env.State().Set(snapshot)
}
return
}