Refactored state, state object and vm

* The State and StateObject have been moved to their own package
* The VM is moved to it's own package

ethchain/state_manager.go

@@ -123,9 +123,9 @@ done:
 
 		cb := state.GetStateObject(coinbase.Address())
 		st := NewStateTransition(cb, tx, state, block)
-		//fmt.Printf("#%d\n", i+1)
 		err = st.TransitionState()
 		if err != nil {
+			statelogger.Infoln(err)
 			switch {
 			case IsNonceErr(err):
 				err = nil // ignore error

ethpub/pub.go

@@ -48,6 +48,12 @@ type PEthereum struct {
 }
 
 func NewPEthereum(manager ethchain.EthManager) *PEthereum {
+	logger.Warnln("DEPRECATED: ethpub.New should be used in favour of ethpub.NewPEthereum")
+
+	return New(manager)
+}
+
+func New(manager ethchain.EthManager) *PEthereum {
 	return &PEthereum{
 		manager,
 		manager.StateManager(),

ethstate/errors.go

+package ethstate
+
+import (
+	"fmt"
+	"math/big"
+)
+
+type GasLimitErr struct {
+	Message string
+	Is, Max *big.Int
+}
+
+func IsGasLimitErr(err error) bool {
+	_, ok := err.(*GasLimitErr)
+
+	return ok
+}
+func (err *GasLimitErr) Error() string {
+	return err.Message
+}
+func GasLimitError(is, max *big.Int) *GasLimitErr {
+	return &GasLimitErr{Message: fmt.Sprintf("GasLimit error. Max %s, transaction would take it to %s", max, is), Is: is, Max: max}
+}

ethstate/state.go

+package ethstate
+
+import (
+	"github.com/ethereum/eth-go/ethcrypto"
+	"github.com/ethereum/eth-go/ethlog"
+	"github.com/ethereum/eth-go/ethtrie"
+	"github.com/ethereum/eth-go/ethutil"
+	"math/big"
+)
+
+var statelogger = ethlog.NewLogger("STATE")
+
+// States within the ethereum protocol are used to store anything
+// within the merkle trie. States take care of caching and storing
+// nested states. It's the general query interface to retrieve:
+// * Contracts
+// * Accounts
+type State struct {
+	// The trie for this structure
+	trie *ethtrie.Trie
+
+	stateObjects map[string]*StateObject
+
+	manifest *Manifest
+}
+
+// Create a new state from a given trie
+func NewState(trie *ethtrie.Trie) *State {
+	return &State{trie: trie, stateObjects: make(map[string]*StateObject), manifest: NewManifest()}
+}
+
+// Retrieve the balance from the given address or 0 if object not found
+func (self *State) GetBalance(addr []byte) *big.Int {
+	stateObject := self.GetStateObject(addr)
+	if stateObject != nil {
+		return stateObject.Amount
+	}
+
+	return ethutil.Big0
+}
+
+func (self *State) GetNonce(addr []byte) uint64 {
+	stateObject := self.GetStateObject(addr)
+	if stateObject != nil {
+		return stateObject.Nonce
+	}
+
+	return 0
+}
+
+//
+// Setting, updating & deleting state object methods
+//
+
+// Update the given state object and apply it to state trie
+func (self *State) UpdateStateObject(stateObject *StateObject) {
+	addr := stateObject.Address()
+
+	ethutil.Config.Db.Put(ethcrypto.Sha3Bin(stateObject.Code), stateObject.Code)
+
+	self.trie.Update(string(addr), string(stateObject.RlpEncode()))
+
+	self.manifest.AddObjectChange(stateObject)
+}
+
+// Delete the given state object and delete it from the state trie
+func (self *State) DeleteStateObject(stateObject *StateObject) {
+	self.trie.Delete(string(stateObject.Address()))
+
+	delete(self.stateObjects, string(stateObject.Address()))
+}
+
+// Retrieve a state object given my the address. Nil if not found
+func (self *State) GetStateObject(addr []byte) *StateObject {
+	addr = ethutil.Address(addr)
+
+	stateObject := self.stateObjects[string(addr)]
+	if stateObject != nil {
+		return stateObject
+	}
+
+	data := self.trie.Get(string(addr))
+	if len(data) == 0 {
+		return nil
+	}
+
+	stateObject = NewStateObjectFromBytes(addr, []byte(data))
+	self.stateObjects[string(addr)] = stateObject
+
+	return stateObject
+}
+
+// Retrieve a state object or create a new state object if nil
+func (self *State) GetOrNewStateObject(addr []byte) *StateObject {
+	stateObject := self.GetStateObject(addr)
+	if stateObject == nil {
+		stateObject = self.NewStateObject(addr)
+	}
+
+	return stateObject
+}
+
+// Create a state object whether it exist in the trie or not
+func (self *State) NewStateObject(addr []byte) *StateObject {
+	addr = ethutil.Address(addr)
+
+	statelogger.Infof("(+) %x\n", addr)
+
+	stateObject := NewStateObject(addr)
+	self.stateObjects[string(addr)] = stateObject
+
+	return stateObject
+}
+
+// Deprecated
+func (self *State) GetAccount(addr []byte) *StateObject {
+	return self.GetOrNewStateObject(addr)
+}
+
+//
+// Setting, copying of the state methods
+//
+
+func (s *State) Cmp(other *State) bool {
+	return s.trie.Cmp(other.trie)
+}
+
+func (self *State) Copy() *State {
+	if self.trie != nil {
+		state := NewState(self.trie.Copy())
+		for k, stateObject := range self.stateObjects {
+			state.stateObjects[k] = stateObject.Copy()
+		}
+
+		return state
+	}
+
+	return nil
+}
+
+func (self *State) Set(state *State) {
+	if state == nil {
+		panic("Tried setting 'state' to nil through 'Set'")
+	}
+
+	self.trie = state.trie
+	self.stateObjects = state.stateObjects
+}
+
+func (s *State) Root() interface{} {
+	return s.trie.Root
+}
+
+// Resets the trie and all siblings
+func (s *State) Reset() {
+	s.trie.Undo()
+
+	// Reset all nested states
+	for _, stateObject := range s.stateObjects {
+		if stateObject.state == nil {
+			continue
+		}
+
+		//stateObject.state.Reset()
+		stateObject.Reset()
+	}
+
+	s.Empty()
+}
+
+// Syncs the trie and all siblings
+func (s *State) Sync() {
+	// Sync all nested states
+	for _, stateObject := range s.stateObjects {
+		//s.UpdateStateObject(stateObject)
+
+		if stateObject.state == nil {
+			continue
+		}
+
+		stateObject.state.Sync()
+	}
+
+	s.trie.Sync()
+
+	s.Empty()
+}
+
+func (self *State) Empty() {
+	self.stateObjects = make(map[string]*StateObject)
+}
+
+func (self *State) Update() {
+	for _, stateObject := range self.stateObjects {
+		if stateObject.remove {
+			self.DeleteStateObject(stateObject)
+		} else {
+			stateObject.Sync()
+
+			self.UpdateStateObject(stateObject)
+		}
+	}
+
+	// FIXME trie delete is broken
+	valid, t2 := ethtrie.ParanoiaCheck(self.trie)
+	if !valid {
+		statelogger.Infof("Warn: PARANOIA: Different state root during copy %x vs %x\n", self.trie.Root, t2.Root)
+
+		self.trie = t2
+	}
+}
+
+// Debug stuff
+func (self *State) CreateOutputForDiff() {
+	for _, stateObject := range self.stateObjects {
+		stateObject.CreateOutputForDiff()
+	}
+}
+
+func (self *State) Manifest() *Manifest {
+	return self.manifest
+}
+
+// Object manifest
+//
+// The object manifest is used to keep changes to the state so we can keep track of the changes
+// that occurred during a state transitioning phase.
+type Manifest struct {
+	// XXX These will be handy in the future. Not important for now.
+	objectAddresses  map[string]bool
+	storageAddresses map[string]map[string]bool
+
+	objectChanges  map[string]*StateObject
+	storageChanges map[string]map[string]*big.Int
+}
+
+func NewManifest() *Manifest {
+	m := &Manifest{objectAddresses: make(map[string]bool), storageAddresses: make(map[string]map[string]bool)}
+	m.Reset()
+
+	return m
+}
+
+func (m *Manifest) Reset() {
+	m.objectChanges = make(map[string]*StateObject)
+	m.storageChanges = make(map[string]map[string]*big.Int)
+}
+
+func (m *Manifest) AddObjectChange(stateObject *StateObject) {
+	m.objectChanges[string(stateObject.Address())] = stateObject
+}
+
+func (m *Manifest) AddStorageChange(stateObject *StateObject, storageAddr []byte, storage *big.Int) {
+	if m.storageChanges[string(stateObject.Address())] == nil {
+		m.storageChanges[string(stateObject.Address())] = make(map[string]*big.Int)
+	}
+
+	m.storageChanges[string(stateObject.Address())][string(storageAddr)] = storage
+}

ethstate/state_object.go

+package ethstate
+
+import (
+	"fmt"
+	"github.com/ethereum/eth-go/ethcrypto"
+	"github.com/ethereum/eth-go/ethtrie"
+	"github.com/ethereum/eth-go/ethutil"
+	"math/big"
+)
+
+type Code []byte
+
+func (self Code) String() string {
+	return "" //strings.Join(Disassemble(self), " ")
+}
+
+type Storage map[string]*ethutil.Value
+
+func (self Storage) Copy() Storage {
+	cpy := make(Storage)
+	for key, value := range self {
+		// XXX Do we need a 'value' copy or is this sufficient?
+		cpy[key] = value
+	}
+
+	return cpy
+}
+
+type StateObject struct {
+	// Address of the object
+	address []byte
+	// Shared attributes
+	Amount   *big.Int
+	CodeHash []byte
+	Nonce    uint64
+	// Contract related attributes
+	state    *State
+	Code     Code
+	initCode Code
+
+	storage Storage
+
+	// Total gas pool is the total amount of gas currently
+	// left if this object is the coinbase. Gas is directly
+	// purchased of the coinbase.
+	gasPool *big.Int
+
+	// Mark for deletion
+	// When an object is marked for deletion it will be delete from the trie
+	// during the "update" phase of the state transition
+	remove bool
+}
+
+func (self *StateObject) Reset() {
+	self.storage = make(Storage)
+	self.state.Reset()
+}
+
+/*
+// Converts an transaction in to a state object
+func MakeContract(tx *Transaction, state *State) *StateObject {
+	// Create contract if there's no recipient
+	if tx.IsContract() {
+		addr := tx.CreationAddress()
+
+		contract := state.NewStateObject(addr)
+		contract.initCode = tx.Data
+		contract.state = NewState(ethtrie.NewTrie(ethutil.Config.Db, ""))
+
+		return contract
+	}
+
+	return nil
+}
+*/
+
+func NewStateObject(addr []byte) *StateObject {
+	// This to ensure that it has 20 bytes (and not 0 bytes), thus left or right pad doesn't matter.
+	address := ethutil.Address(addr)
+
+	object := &StateObject{address: address, Amount: new(big.Int), gasPool: new(big.Int)}
+	object.state = NewState(ethtrie.NewTrie(ethutil.Config.Db, ""))
+	object.storage = make(Storage)
+	object.gasPool = new(big.Int)
+
+	return object
+}
+
+func NewContract(address []byte, Amount *big.Int, root []byte) *StateObject {
+	contract := NewStateObject(address)
+	contract.Amount = Amount
+	contract.state = NewState(ethtrie.NewTrie(ethutil.Config.Db, string(root)))
+
+	return contract
+}
+
+func NewStateObjectFromBytes(address, data []byte) *StateObject {
+	object := &StateObject{address: address}
+	object.RlpDecode(data)
+
+	return object
+}
+
+func (self *StateObject) MarkForDeletion() {
+	self.remove = true
+	statelogger.DebugDetailf("%x: #%d %v (deletion)\n", self.Address(), self.Nonce, self.Amount)
+}
+
+func (c *StateObject) GetAddr(addr []byte) *ethutil.Value {
+	return ethutil.NewValueFromBytes([]byte(c.state.trie.Get(string(addr))))
+}
+
+func (c *StateObject) SetAddr(addr []byte, value interface{}) {
+	c.state.trie.Update(string(addr), string(ethutil.NewValue(value).Encode()))
+}
+
+func (self *StateObject) GetStorage(key *big.Int) *ethutil.Value {
+	return self.getStorage(key.Bytes())
+}
+func (self *StateObject) SetStorage(key *big.Int, value *ethutil.Value) {
+	self.setStorage(key.Bytes(), value)
+}
+
+func (self *StateObject) getStorage(k []byte) *ethutil.Value {
+	key := ethutil.LeftPadBytes(k, 32)
+
+	value := self.storage[string(key)]
+	if value == nil {
+		value = self.GetAddr(key)
+
+		if !value.IsNil() {
+			self.storage[string(key)] = value
+		}
+	}
+
+	return value
+
+	//return self.GetAddr(key)
+}
+
+func (self *StateObject) setStorage(k []byte, value *ethutil.Value) {
+	key := ethutil.LeftPadBytes(k, 32)
+	self.storage[string(key)] = value.Copy()
+}
+
+// Iterate over each storage address and yield callback
+func (self *StateObject) EachStorage(cb ethtrie.EachCallback) {
+	// First loop over the uncommit/cached values in storage
+	for key, value := range self.storage {
+		// XXX Most iterators Fns as it stands require encoded values
+		encoded := ethutil.NewValue(value.Encode())
+		cb(key, encoded)
+	}
+
+	it := self.state.trie.NewIterator()
+	it.Each(func(key string, value *ethutil.Value) {
+		// If it's cached don't call the callback.
+		if self.storage[key] == nil {
+			cb(key, value)
+		}
+	})
+}
+
+func (self *StateObject) Sync() {
+	for key, value := range self.storage {
+		if value.Len() == 0 { // value.BigInt().Cmp(ethutil.Big0) == 0 {
+			//data := self.getStorage([]byte(key))
+			//fmt.Printf("deleting %x %x 0x%x\n", self.Address(), []byte(key), data)
+			self.state.trie.Delete(string(key))
+			continue
+		}
+
+		self.SetAddr([]byte(key), value)
+	}
+
+	valid, t2 := ethtrie.ParanoiaCheck(self.state.trie)
+	if !valid {
+		statelogger.Infof("Warn: PARANOIA: Different state storage root during copy %x vs %x\n", self.state.trie.Root, t2.Root)
+
+		self.state.trie = t2
+	}
+}
+
+func (c *StateObject) GetInstr(pc *big.Int) *ethutil.Value {
+	if int64(len(c.Code)-1) < pc.Int64() {
+		return ethutil.NewValue(0)
+	}
+
+	return ethutil.NewValueFromBytes([]byte{c.Code[pc.Int64()]})
+}
+
+func (c *StateObject) AddAmount(amount *big.Int) {
+	c.SetAmount(new(big.Int).Add(c.Amount, amount))
+
+	statelogger.Debugf("%x: #%d %v (+ %v)\n", c.Address(), c.Nonce, c.Amount, amount)
+}
+
+func (c *StateObject) SubAmount(amount *big.Int) {
+	c.SetAmount(new(big.Int).Sub(c.Amount, amount))
+
+	statelogger.Debugf("%x: #%d %v (- %v)\n", c.Address(), c.Nonce, c.Amount, amount)
+}
+
+func (c *StateObject) SetAmount(amount *big.Int) {
+	c.Amount = amount
+}
+
+//
+// Gas setters and getters
+//
+
+// Return the gas back to the origin. Used by the Virtual machine or Closures
+func (c *StateObject) ReturnGas(gas, price *big.Int) {}
+func (c *StateObject) ConvertGas(gas, price *big.Int) error {
+	total := new(big.Int).Mul(gas, price)
+	if total.Cmp(c.Amount) > 0 {
+		return fmt.Errorf("insufficient amount: %v, %v", c.Amount, total)
+	}
+
+	c.SubAmount(total)
+
+	return nil
+}
+
+func (self *StateObject) SetGasPool(gasLimit *big.Int) {
+	self.gasPool = new(big.Int).Set(gasLimit)
+
+	statelogger.DebugDetailf("%x: fuel (+ %v)", self.Address(), self.gasPool)
+}
+
+func (self *StateObject) BuyGas(gas, price *big.Int) error {
+	if self.gasPool.Cmp(gas) < 0 {
+		return GasLimitError(self.gasPool, gas)
+	}
+
+	rGas := new(big.Int).Set(gas)
+	rGas.Mul(rGas, price)
+
+	self.AddAmount(rGas)
+
+	return nil
+}
+
+func (self *StateObject) RefundGas(gas, price *big.Int) {
+	self.gasPool.Add(self.gasPool, gas)
+
+	rGas := new(big.Int).Set(gas)
+	rGas.Mul(rGas, price)
+
+	self.Amount.Sub(self.Amount, rGas)
+}
+
+func (self *StateObject) Copy() *StateObject {
+	stateObject := NewStateObject(self.Address())
+	stateObject.Amount.Set(self.Amount)
+	stateObject.CodeHash = ethutil.CopyBytes(self.CodeHash)
+	stateObject.Nonce = self.Nonce
+	if self.state != nil {
+		stateObject.state = self.state.Copy()
+	}
+	stateObject.Code = ethutil.CopyBytes(self.Code)
+	stateObject.initCode = ethutil.CopyBytes(self.initCode)
+	stateObject.storage = self.storage.Copy()
+	stateObject.gasPool.Set(self.gasPool)
+
+	return stateObject
+}
+
+func (self *StateObject) Set(stateObject *StateObject) {
+	*self = *stateObject
+}
+
+//
+// Attribute accessors
+//
+
+func (c *StateObject) State() *State {
+	return c.state
+}
+
+func (c *StateObject) N() *big.Int {
+	return big.NewInt(int64(c.Nonce))
+}
+
+// Returns the address of the contract/account
+func (c *StateObject) Address() []byte {
+	return c.address
+}
+
+// Returns the initialization Code
+func (c *StateObject) Init() Code {
+	return c.initCode
+}
+
+// Debug stuff
+func (self *StateObject) CreateOutputForDiff() {
+	fmt.Printf("%x %x %x %x\n", self.Address(), self.state.Root(), self.Amount.Bytes(), self.Nonce)
+	self.EachStorage(func(addr string, value *ethutil.Value) {
+		fmt.Printf("%x %x\n", addr, value.Bytes())
+	})
+}
+
+//
+// Encoding
+//
+
+// State object encoding methods
+func (c *StateObject) RlpEncode() []byte {
+	var root interface{}
+	if c.state != nil {
+		root = c.state.trie.Root
+	} else {
+		root = ""
+	}
+
+	return ethutil.Encode([]interface{}{c.Nonce, c.Amount, root, ethcrypto.Sha3Bin(c.Code)})
+}
+
+func (c *StateObject) RlpDecode(data []byte) {
+	decoder := ethutil.NewValueFromBytes(data)
+
+	c.Nonce = decoder.Get(0).Uint()
+	c.Amount = decoder.Get(1).BigInt()
+	c.state = NewState(ethtrie.NewTrie(ethutil.Config.Db, decoder.Get(2).Interface()))
+	c.storage = make(map[string]*ethutil.Value)
+	c.gasPool = new(big.Int)
+
+	c.CodeHash = decoder.Get(3).Bytes()
+
+	c.Code, _ = ethutil.Config.Db.Get(c.CodeHash)
+}
+
+// Storage change object. Used by the manifest for notifying changes to
+// the sub channels.
+type StorageState struct {
+	StateAddress []byte
+	Address      []byte
+	Value        *big.Int
+}

ethstate/state_test.go

+package ethstate
+
+import (
+	"github.com/ethereum/eth-go/ethdb"
+	"github.com/ethereum/eth-go/ethtrie"
+	"github.com/ethereum/eth-go/ethutil"
+	"testing"
+)
+
+var ZeroHash256 = make([]byte, 32)
+
+func TestSnapshot(t *testing.T) {
+	db, _ := ethdb.NewMemDatabase()
+	ethutil.ReadConfig(".ethtest", "/tmp/ethtest", "")
+	ethutil.Config.Db = db
+
+	state := NewState(ethtrie.NewTrie(db, ""))
+
+	stateObject := state.GetOrNewStateObject([]byte("aa"))
+
+	stateObject.SetStorage(ethutil.Big("0"), ethutil.NewValue(42))
+
+	snapshot := state.Copy()
+
+	stateObject = state.GetStateObject([]byte("aa"))
+	stateObject.SetStorage(ethutil.Big("0"), ethutil.NewValue(43))
+
+	state.Set(snapshot)
+
+	stateObject = state.GetStateObject([]byte("aa"))
+	res := stateObject.GetStorage(ethutil.Big("0"))
+	if !res.Cmp(ethutil.NewValue(42)) {
+		t.Error("Expected storage 0 to be 42", res)
+	}
+}

ethvm/asm.go

+package ethvm
+
+import (
+	"fmt"
+	"github.com/ethereum/eth-go/ethutil"
+	"math/big"
+)
+
+func Disassemble(script []byte) (asm []string) {
+	pc := new(big.Int)
+	for {
+		if pc.Cmp(big.NewInt(int64(len(script)))) >= 0 {
+			return
+		}
+
+		// Get the memory location of pc
+		val := script[pc.Int64()]
+		// Get the opcode (it must be an opcode!)
+		op := OpCode(val)
+
+		asm = append(asm, fmt.Sprintf("%04v: %v", pc, op))
+
+		switch op {
+		case PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8, PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16, PUSH17, PUSH18, PUSH19, PUSH20, PUSH21, PUSH22, PUSH23, PUSH24, PUSH25, PUSH26, PUSH27, PUSH28, PUSH29, PUSH30, PUSH31, PUSH32:
+			pc.Add(pc, ethutil.Big1)
+			a := int64(op) - int64(PUSH1) + 1
+			if int(pc.Int64()+a) > len(script) {
+				return nil
+			}
+
+			data := script[pc.Int64() : pc.Int64()+a]
+			if len(data) == 0 {
+				data = []byte{0}
+			}
+			asm = append(asm, fmt.Sprintf("%04v: 0x%x", pc, data))
+
+			pc.Add(pc, big.NewInt(a-1))
+		}
+
+		pc.Add(pc, ethutil.Big1)
+	}
+
+	return
+}

ethvm/closure.go

+package ethvm
+
+// TODO Re write VM to use values instead of big integers?
+
+import (
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethutil"
+	"math/big"
+)
+
+type ClosureRef interface {
+	ReturnGas(*big.Int, *big.Int)
+	Address() []byte
+	GetStorage(*big.Int) *ethutil.Value
+	SetStorage(*big.Int, *ethutil.Value)
+}
+
+// Basic inline closure object which implement the 'closure' interface
+type Closure struct {
+	caller ClosureRef
+	object *ethstate.StateObject
+	Code   []byte
+
+	Gas, UsedGas, Price *big.Int
+
+	Args []byte
+}
+
+// Create a new closure for the given data items
+func NewClosure(caller ClosureRef, object *ethstate.StateObject, code []byte, gas, price *big.Int) *Closure {
+	c := &Closure{caller: caller, object: object, Code: code, Args: nil}
+
+	// Gas should be a pointer so it can safely be reduced through the run
+	// This pointer will be off the state transition
+	c.Gas = gas //new(big.Int).Set(gas)
+	// In most cases price and value are pointers to transaction objects
+	// and we don't want the transaction's values to change.
+	c.Price = new(big.Int).Set(price)
+	c.UsedGas = new(big.Int)
+
+	return c
+}
+
+// Retuns the x element in data slice
+func (c *Closure) GetStorage(x *big.Int) *ethutil.Value {
+	m := c.object.GetStorage(x)
+	if m == nil {
+		return ethutil.EmptyValue()
+	}
+
+	return m
+}
+
+func (c *Closure) Get(x *big.Int) *ethutil.Value {
+	return c.Gets(x, big.NewInt(1))
+}
+
+func (c *Closure) Gets(x, y *big.Int) *ethutil.Value {
+	if x.Int64() >= int64(len(c.Code)) || y.Int64() >= int64(len(c.Code)) {
+		return ethutil.NewValue(0)
+	}
+
+	partial := c.Code[x.Int64() : x.Int64()+y.Int64()]
+
+	return ethutil.NewValue(partial)
+}
+
+func (c *Closure) SetStorage(x *big.Int, val *ethutil.Value) {
+	c.object.SetStorage(x, val)
+}
+
+func (c *Closure) Address() []byte {
+	return c.object.Address()
+}
+
+func (c *Closure) Call(vm *Vm, args []byte) ([]byte, *big.Int, error) {
+	c.Args = args
+
+	ret, err := vm.RunClosure(c)
+
+	return ret, c.UsedGas, err
+}
+
+func (c *Closure) Return(ret []byte) []byte {
+	// Return the remaining gas to the caller
+	c.caller.ReturnGas(c.Gas, c.Price)
+
+	return ret
+}
+
+func (c *Closure) UseGas(gas *big.Int) bool {
+	if c.Gas.Cmp(gas) < 0 {
+		return false
+	}
+
+	// Sub the amount of gas from the remaining
+	c.Gas.Sub(c.Gas, gas)
+	c.UsedGas.Add(c.UsedGas, gas)
+
+	return true
+}
+
+// Implement the caller interface
+func (c *Closure) ReturnGas(gas, price *big.Int) {
+	// Return the gas to the closure
+	c.Gas.Add(c.Gas, gas)
+	c.UsedGas.Sub(c.UsedGas, gas)
+}
+
+func (c *Closure) Object() *ethstate.StateObject {
+	return c.object
+}
+
+func (c *Closure) Caller() ClosureRef {
+	return c.caller
+}

ethvm/common.go

+package ethvm
+
+import (
+	"github.com/ethereum/eth-go/ethlog"
+	"github.com/ethereum/eth-go/ethutil"
+	"math/big"
+)
+
+var vmlogger = ethlog.NewLogger("VM")
+
+var (
+	GasStep    = big.NewInt(1)
+	GasSha     = big.NewInt(20)
+	GasSLoad   = big.NewInt(20)
+	GasSStore  = big.NewInt(100)
+	GasBalance = big.NewInt(20)
+	GasCreate  = big.NewInt(100)
+	GasCall    = big.NewInt(20)
+	GasMemory  = big.NewInt(1)
+	GasData    = big.NewInt(5)
+	GasTx      = big.NewInt(500)
+
+	Pow256 = ethutil.BigPow(2, 256)
+
+	LogTyPretty byte = 0x1
+	LogTyDiff   byte = 0x2
+)

ethvm/stack.go

+package ethvm
+
+import (
+	"fmt"
+	"math"
+	"math/big"
+)
+
+type OpType int
+
+const (
+	tNorm = iota
+	tData
+	tExtro
+	tCrypto
+)
+
+type TxCallback func(opType OpType) bool
+
+// Simple push/pop stack mechanism
+type Stack struct {
+	data []*big.Int
+}
+
+func NewStack() *Stack {
+	return &Stack{}
+}
+
+func (st *Stack) Data() []*big.Int {
+	return st.data
+}
+
+func (st *Stack) Len() int {
+	return len(st.data)
+}
+
+func (st *Stack) Pop() *big.Int {
+	str := st.data[len(st.data)-1]
+
+	copy(st.data[:len(st.data)-1], st.data[:len(st.data)-1])
+	st.data = st.data[:len(st.data)-1]
+
+	return str
+}
+
+func (st *Stack) Popn() (*big.Int, *big.Int) {
+	ints := st.data[len(st.data)-2:]
+
+	copy(st.data[:len(st.data)-2], st.data[:len(st.data)-2])
+	st.data = st.data[:len(st.data)-2]
+
+	return ints[0], ints[1]
+}
+
+func (st *Stack) Peek() *big.Int {
+	str := st.data[len(st.data)-1]
+
+	return str
+}
+
+func (st *Stack) Peekn() (*big.Int, *big.Int) {
+	ints := st.data[:2]
+
+	return ints[0], ints[1]
+}
+
+func (st *Stack) Push(d *big.Int) {
+	st.data = append(st.data, new(big.Int).Set(d))
+}
+
+func (st *Stack) Get(amount *big.Int) []*big.Int {
+	// offset + size <= len(data)
+	length := big.NewInt(int64(len(st.data)))
+	if amount.Cmp(length) <= 0 {
+		start := new(big.Int).Sub(length, amount)
+		return st.data[start.Int64():length.Int64()]
+	}
+
+	return nil
+}
+
+func (st *Stack) Print() {
+	fmt.Println("### stack ###")
+	if len(st.data) > 0 {
+		for i, val := range st.data {
+			fmt.Printf("%-3d  %v\n", i, val)
+		}
+	} else {
+		fmt.Println("-- empty --")
+	}
+	fmt.Println("#############")
+}
+
+type Memory struct {
+	store []byte
+}
+
+func (m *Memory) Set(offset, size int64, value []byte) {
+	totSize := offset + size
+	lenSize := int64(len(m.store) - 1)
+	if totSize > lenSize {
+		// Calculate the diff between the sizes
+		diff := totSize - lenSize
+		if diff > 0 {
+			// Create a new empty slice and append it
+			newSlice := make([]byte, diff-1)
+			// Resize slice
+			m.store = append(m.store, newSlice...)
+		}
+	}
+	copy(m.store[offset:offset+size], value)
+}
+
+func (m *Memory) Resize(size uint64) {
+	if uint64(m.Len()) < size {
+		m.store = append(m.store, make([]byte, size-uint64(m.Len()))...)
+	}
+}
+
+func (m *Memory) Get(offset, size int64) []byte {
+	if len(m.store) > int(offset) {
+		end := int(math.Min(float64(len(m.store)), float64(offset+size)))
+
+		return m.store[offset:end]
+	}
+
+	return nil
+}
+
+func (m *Memory) Len() int {
+	return len(m.store)
+}
+
+func (m *Memory) Data() []byte {
+	return m.store
+}
+
+func (m *Memory) Print() {
+	fmt.Printf("### mem %d bytes ###\n", len(m.store))
+	if len(m.store) > 0 {
+		addr := 0
+		for i := 0; i+32 <= len(m.store); i += 32 {
+			fmt.Printf("%03d: % x\n", addr, m.store[i:i+32])
+			addr++
+		}
+	} else {
+		fmt.Println("-- empty --")
+	}
+	fmt.Println("####################")
+}

ethvm/types.go

+package ethvm
+
+import (
+	"fmt"
+)
+
+type OpCode int
+
+// Op codes
+const (
+	// 0x0 range - arithmetic ops
+	STOP = 0x00
+	ADD  = 0x01
+	MUL  = 0x02
+	SUB  = 0x03
+	DIV  = 0x04
+	SDIV = 0x05
+	MOD  = 0x06
+	SMOD = 0x07
+	EXP  = 0x08
+	NEG  = 0x09
+	LT   = 0x0a
+	GT   = 0x0b
+	SLT  = 0x0c
+	SGT  = 0x0d
+	EQ   = 0x0e
+	NOT  = 0x0f
+
+	// 0x10 range - bit ops
+	AND  = 0x10
+	OR   = 0x11
+	XOR  = 0x12
+	BYTE = 0x13
+
+	// 0x20 range - crypto
+	SHA3 = 0x20
+
+	// 0x30 range - closure state
+	ADDRESS      = 0x30
+	BALANCE      = 0x31
+	ORIGIN       = 0x32
+	CALLER       = 0x33
+	CALLVALUE    = 0x34
+	CALLDATALOAD = 0x35
+	CALLDATASIZE = 0x36
+	CALLDATACOPY = 0x37
+	CODESIZE     = 0x38
+	CODECOPY     = 0x39
+	GASPRICE     = 0x3a
+
+	// 0x40 range - block operations
+	PREVHASH   = 0x40
+	COINBASE   = 0x41
+	TIMESTAMP  = 0x42
+	NUMBER     = 0x43
+	DIFFICULTY = 0x44
+	GASLIMIT   = 0x45
+
+	// 0x50 range - 'storage' and execution
+	POP     = 0x50
+	DUP     = 0x51
+	SWAP    = 0x52
+	MLOAD   = 0x53
+	MSTORE  = 0x54
+	MSTORE8 = 0x55
+	SLOAD   = 0x56
+	SSTORE  = 0x57
+	JUMP    = 0x58
+	JUMPI   = 0x59
+	PC      = 0x5a
+	MSIZE   = 0x5b
+	GAS     = 0x5c
+
+	// 0x60 range
+	PUSH1  = 0x60
+	PUSH2  = 0x61
+	PUSH3  = 0x62
+	PUSH4  = 0x63
+	PUSH5  = 0x64
+	PUSH6  = 0x65
+	PUSH7  = 0x66
+	PUSH8  = 0x67
+	PUSH9  = 0x68
+	PUSH10 = 0x69
+	PUSH11 = 0x6a
+	PUSH12 = 0x6b
+	PUSH13 = 0x6c
+	PUSH14 = 0x6d
+	PUSH15 = 0x6e
+	PUSH16 = 0x6f
+	PUSH17 = 0x70
+	PUSH18 = 0x71
+	PUSH19 = 0x72
+	PUSH20 = 0x73
+	PUSH21 = 0x74
+	PUSH22 = 0x75
+	PUSH23 = 0x76
+	PUSH24 = 0x77
+	PUSH25 = 0x78
+	PUSH26 = 0x79
+	PUSH27 = 0x7a
+	PUSH28 = 0x7b
+	PUSH29 = 0x7c
+	PUSH30 = 0x7d
+	PUSH31 = 0x7e
+	PUSH32 = 0x7f
+
+	// 0xf0 range - closures
+	CREATE = 0xf0
+	CALL   = 0xf1
+	RETURN = 0xf2
+
+	// 0x70 range - other
+	LOG     = 0xfe // XXX Unofficial
+	SUICIDE = 0xff
+)
+
+// Since the opcodes aren't all in order we can't use a regular slice
+var opCodeToString = map[OpCode]string{
+	// 0x0 range - arithmetic ops
+	STOP: "STOP",
+	ADD:  "ADD",
+	MUL:  "MUL",
+	SUB:  "SUB",
+	DIV:  "DIV",
+	SDIV: "SDIV",
+	MOD:  "MOD",
+	SMOD: "SMOD",
+	EXP:  "EXP",
+	NEG:  "NEG",
+	LT:   "LT",
+	GT:   "GT",
+	SLT:  "SLT",
+	SGT:  "SGT",
+	EQ:   "EQ",
+	NOT:  "NOT",
+
+	// 0x10 range - bit ops
+	AND:  "AND",
+	OR:   "OR",
+	XOR:  "XOR",
+	BYTE: "BYTE",
+
+	// 0x20 range - crypto
+	SHA3: "SHA3",
+
+	// 0x30 range - closure state
+	ADDRESS:      "ADDRESS",
+	BALANCE:      "BALANCE",
+	ORIGIN:       "ORIGIN",
+	CALLER:       "CALLER",
+	CALLVALUE:    "CALLVALUE",
+	CALLDATALOAD: "CALLDATALOAD",
+	CALLDATASIZE: "CALLDATASIZE",
+	CALLDATACOPY: "CALLDATACOPY",
+	CODESIZE:     "CODESIZE",
+	CODECOPY:     "CODECOPY",
+	GASPRICE:     "TXGASPRICE",
+
+	// 0x40 range - block operations
+	PREVHASH:   "PREVHASH",
+	COINBASE:   "COINBASE",
+	TIMESTAMP:  "TIMESTAMP",
+	NUMBER:     "NUMBER",
+	DIFFICULTY: "DIFFICULTY",
+	GASLIMIT:   "GASLIMIT",
+
+	// 0x50 range - 'storage' and execution
+	POP:     "POP",
+	DUP:     "DUP",
+	SWAP:    "SWAP",
+	MLOAD:   "MLOAD",
+	MSTORE:  "MSTORE",
+	MSTORE8: "MSTORE8",
+	SLOAD:   "SLOAD",
+	SSTORE:  "SSTORE",
+	JUMP:    "JUMP",
+	JUMPI:   "JUMPI",
+	PC:      "PC",
+	MSIZE:   "MSIZE",
+	GAS:     "GAS",
+
+	// 0x60 range - push
+	PUSH1:  "PUSH1",
+	PUSH2:  "PUSH2",
+	PUSH3:  "PUSH3",
+	PUSH4:  "PUSH4",
+	PUSH5:  "PUSH5",
+	PUSH6:  "PUSH6",
+	PUSH7:  "PUSH7",
+	PUSH8:  "PUSH8",
+	PUSH9:  "PUSH9",
+	PUSH10: "PUSH10",
+	PUSH11: "PUSH11",
+	PUSH12: "PUSH12",
+	PUSH13: "PUSH13",
+	PUSH14: "PUSH14",
+	PUSH15: "PUSH15",
+	PUSH16: "PUSH16",
+	PUSH17: "PUSH17",
+	PUSH18: "PUSH18",
+	PUSH19: "PUSH19",
+	PUSH20: "PUSH20",
+	PUSH21: "PUSH21",
+	PUSH22: "PUSH22",
+	PUSH23: "PUSH23",
+	PUSH24: "PUSH24",
+	PUSH25: "PUSH25",
+	PUSH26: "PUSH26",
+	PUSH27: "PUSH27",
+	PUSH28: "PUSH28",
+	PUSH29: "PUSH29",
+	PUSH30: "PUSH30",
+	PUSH31: "PUSH31",
+	PUSH32: "PUSH32",
+
+	// 0xf0 range
+	CREATE: "CREATE",
+	CALL:   "CALL",
+	RETURN: "RETURN",
+
+	// 0x70 range - other
+	LOG:     "LOG",
+	SUICIDE: "SUICIDE",
+}
+
+func (o OpCode) String() string {
+	str := opCodeToString[o]
+	if len(str) == 0 {
+		return fmt.Sprintf("Missing opcode 0x%x", int(o))
+	}
+
+	return str
+}
+
+// Op codes for assembling
+var OpCodes = map[string]byte{
+	// 0x0 range - arithmetic ops
+	"STOP": 0x00,
+	"ADD":  0x01,
+	"MUL":  0x02,
+	"SUB":  0x03,
+	"DIV":  0x04,
+	"SDIV": 0x05,
+	"MOD":  0x06,
+	"SMOD": 0x07,
+	"EXP":  0x08,
+	"NEG":  0x09,
+	"LT":   0x0a,
+	"GT":   0x0b,
+	"EQ":   0x0c,
+	"NOT":  0x0d,
+
+	// 0x10 range - bit ops
+	"AND":  0x10,
+	"OR":   0x11,
+	"XOR":  0x12,
+	"BYTE": 0x13,
+
+	// 0x20 range - crypto
+	"SHA3": 0x20,
+
+	// 0x30 range - closure state
+	"ADDRESS":      0x30,
+	"BALANCE":      0x31,
+	"ORIGIN":       0x32,
+	"CALLER":       0x33,
+	"CALLVALUE":    0x34,
+	"CALLDATALOAD": 0x35,
+	"CALLDATASIZE": 0x36,
+	"GASPRICE":     0x38,
+
+	// 0x40 range - block operations
+	"PREVHASH":   0x40,
+	"COINBASE":   0x41,
+	"TIMESTAMP":  0x42,
+	"NUMBER":     0x43,
+	"DIFFICULTY": 0x44,
+	"GASLIMIT":   0x45,
+
+	// 0x50 range - 'storage' and execution
+	"POP":     0x51,
+	"DUP":     0x52,
+	"SWAP":    0x53,
+	"MLOAD":   0x54,
+	"MSTORE":  0x55,
+	"MSTORE8": 0x56,
+	"SLOAD":   0x57,
+	"SSTORE":  0x58,
+	"JUMP":    0x59,
+	"JUMPI":   0x5a,
+	"PC":      0x5b,
+	"MSIZE":   0x5c,
+
+	// 0x70 range - 'push'
+	"PUSH1":  0x60,
+	"PUSH2":  0x61,
+	"PUSH3":  0x62,
+	"PUSH4":  0x63,
+	"PUSH5":  0x64,
+	"PUSH6":  0x65,
+	"PUSH7":  0x66,
+	"PUSH8":  0x67,
+	"PUSH9":  0x68,
+	"PUSH10": 0x69,
+	"PUSH11": 0x6a,
+	"PUSH12": 0x6b,
+	"PUSH13": 0x6c,
+	"PUSH14": 0x6d,
+	"PUSH15": 0x6e,
+	"PUSH16": 0x6f,
+	"PUSH17": 0x70,
+	"PUSH18": 0x71,
+	"PUSH19": 0x72,
+	"PUSH20": 0x73,
+	"PUSH21": 0x74,
+	"PUSH22": 0x75,
+	"PUSH23": 0x76,
+	"PUSH24": 0x77,
+	"PUSH25": 0x78,
+	"PUSH26": 0x70,
+	"PUSH27": 0x7a,
+	"PUSH28": 0x7b,
+	"PUSH29": 0x7c,
+	"PUSH30": 0x7d,
+	"PUSH31": 0x7e,
+	"PUSH32": 0x7f,
+
+	// 0xf0 range - closures
+	"CREATE": 0xf0,
+	"CALL":   0xf1,
+	"RETURN": 0xf2,
+
+	// 0x70 range - other
+	"LOG":     0xfe,
+	"SUICIDE": 0x7f,
+}
+
+func IsOpCode(s string) bool {
+	for key, _ := range OpCodes {
+		if key == s {
+			return true
+		}
+	}
+	return false
+}

ethvm/vm_test.go

+package ethvm
+
+import (
+	"fmt"
+	"github.com/ethereum/eth-go/ethdb"
+	"github.com/ethereum/eth-go/ethlog"
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethutil"
+	"log"
+	"math/big"
+	"os"
+	"testing"
+)
+
+type TestEnv struct {
+}
+
+func (self TestEnv) GetObject() Object               { return nil }
+func (self TestEnv) Origin() []byte                  { return nil }
+func (self TestEnv) BlockNumber() *big.Int           { return nil }
+func (self TestEnv) PrevHash() []byte                { return nil }
+func (self TestEnv) Coinbase() []byte                { return nil }
+func (self TestEnv) Time() int64                     { return 0 }
+func (self TestEnv) Difficulty() *big.Int            { return nil }
+func (self TestEnv) Data() []string                  { return nil }
+func (self TestEnv) Value() *big.Int                 { return nil }
+func (self TestEnv) GetBalance(addr []byte) *big.Int { return nil }
+func (self TestEnv) State() *ethstate.State          { return nil }
+
+func TestVm(t *testing.T) {
+	ethlog.AddLogSystem(ethlog.NewStdLogSystem(os.Stdout, log.LstdFlags, ethlog.LogLevel(4)))
+
+	db, _ := ethdb.NewMemDatabase()
+	ethutil.ReadConfig(".ethtest", "/tmp/ethtest", "")
+	ethutil.Config.Db = db
+
+	stateObject := ethstate.NewStateObject([]byte{'j', 'e', 'f', 'f'})
+	callerClosure := NewClosure(stateObject, stateObject, []byte{0x60, 0x01}, big.NewInt(1000000), big.NewInt(0))
+
+	vm := New(TestEnv{})
+	vm.Verbose = true
+
+	ret, _, e := callerClosure.Call(vm, nil)
+	if e != nil {
+		fmt.Println("error", e)
+	}
+	fmt.Println(ret)
+}