plugeth/ethvm/execution.go
2014-10-14 13:37:26 +02:00

82 lines
2.1 KiB
Go

package ethvm
import (
"fmt"
"math/big"
"github.com/ethereum/eth-go/ethstate"
"github.com/ethereum/eth-go/ethutil"
)
type Execution struct {
vm VirtualMachine
closure *Closure
address, input []byte
gas, price, value *big.Int
object *ethstate.StateObject
}
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) (ret []byte, err error) {
env := self.vm.Env()
snapshot := env.State().Copy()
msg := env.State().Manifest().AddMessage(&ethstate.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,
})
object := caller.Object()
if object.Balance.Cmp(self.value) < 0 {
caller.ReturnGas(self.gas, self.price)
err = fmt.Errorf("Insufficient funds to transfer value. Req %v, has %v", self.value, object.Balance)
} else {
stateObject := env.State().GetOrNewStateObject(self.address)
self.object = stateObject
caller.Object().SubAmount(self.value)
stateObject.AddAmount(self.value)
// Precompiled contracts (address.go) 1, 2 & 3.
naddr := ethutil.BigD(codeAddr).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 {
if self.vm.Depth() == MaxCallDepth {
return nil, fmt.Errorf("Max call depth exceeded (%d)", MaxCallDepth)
}
// Retrieve the executing code
code := env.State().GetCode(codeAddr)
// Create a new callable closure
c := NewClosure(msg, caller, stateObject, code, self.gas, self.price)
// Executer the closure and get the return value (if any)
ret, _, err = c.Call(self.vm, self.input)
msg.Output = ret
}
}
if err != nil {
env.State().Set(snapshot)
}
return
}