package vm import ( "fmt" "math/big" "github.com/ethereum/go-ethereum/ethutil" "github.com/ethereum/go-ethereum/state" ) type Execution struct { vm VirtualMachine address, input []byte Gas, price, value *big.Int object *state.StateObject SkipTransfer bool } func NewExecution(vm VirtualMachine, address, input []byte, gas, gasPrice, value *big.Int) *Execution { return &Execution{vm: vm, address: address, input: input, Gas: gas, price: gasPrice, value: value} } func (self *Execution) Addr() []byte { return self.address } func (self *Execution) Exec(codeAddr []byte, caller ClosureRef) ([]byte, error) { // Retrieve the executing code code := self.vm.Env().State().GetCode(codeAddr) return self.exec(code, codeAddr, caller) } func (self *Execution) exec(code, caddr []byte, caller ClosureRef) (ret []byte, err error) { env := self.vm.Env() snapshot := env.State().Copy() defer func() { if IsDepthErr(err) || IsOOGErr(err) { env.State().Set(snapshot) } }() msg := env.State().Manifest().AddMessage(&state.Message{ To: self.address, From: caller.Address(), Input: self.input, Origin: env.Origin(), Block: env.BlockHash(), Timestamp: env.Time(), Coinbase: env.Coinbase(), Number: env.BlockNumber(), Value: self.value, }) from, to := caller.Object(), env.State().GetOrNewStateObject(self.address) // Skipping transfer is used on testing for the initial call if !self.SkipTransfer { err = env.Transfer(from, to, self.value) } if err != nil { caller.ReturnGas(self.Gas, self.price) err = fmt.Errorf("Insufficient funds to transfer value. Req %v, has %v", self.value, from.Balance) } else { self.object = to // Pre-compiled contracts (address.go) 1, 2 & 3. naddr := ethutil.BigD(caddr).Uint64() if p := Precompiled[naddr]; p != nil { if self.Gas.Cmp(p.Gas) >= 0 { ret = p.Call(self.input) self.vm.Printf("NATIVE_FUNC(%x) => %x", naddr, ret) } } else { // Create a new callable closure c := NewClosure(msg, caller, to, code, self.Gas, self.price) c.exe = self if self.vm.Depth() == MaxCallDepth { c.UseGas(self.Gas) return c.Return(nil), DepthError{} } // Executer the closure and get the return value (if any) ret, _, err = c.Call(self.vm, self.input) msg.Output = ret } } return } func (self *Execution) Create(caller ClosureRef) (ret []byte, err error) { return self.exec(self.input, nil, caller) }