1 files changed, 95 insertions, 0 deletions
diff --git a/core/execution.go b/core/execution.go
new file mode 100644
index 000000000..93fb03ecc
--- /dev/null
+++ b/core/execution.go
@@ -0,0 +1,95 @@
+package core
+
+import (
+	"math/big"
+	"time"
+
+	"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"
+)
+
+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) {
+	ret, err = self.exec(nil, self.input, caller)
+	account = self.env.State().GetStateObject(*self.address)
+	return
+}
+
+func (self *Execution) exec(contextAddr *common.Address, code []byte, caller vm.ContextRef) (ret []byte, err error) {
+	start := time.Now()
+
+	env := self.env
+	evm := self.evm
+	if env.Depth() == vm.MaxCallDepth {
+		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)
+	evm.Printf("message call took %v", time.Since(start)).Endl()
+	if err != nil {
+		env.State().Set(snapshot)
+	}
+
+	return
+}