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authorobscuren <geffobscura@gmail.com>2014-10-31 21:43:14 +0800
committerobscuren <geffobscura@gmail.com>2014-10-31 21:43:14 +0800
commitaf8f5f0b69f1c359991d12c7708804fe8dd1f944 (patch)
treedd3d5bea8d57037a2d32fae86c4ba7fcc9161b16 /state
parent0ed1a8b50a9b9726cd57a2731d0405f6949c6188 (diff)
downloaddexon-af8f5f0b69f1c359991d12c7708804fe8dd1f944.tar.gz
dexon-af8f5f0b69f1c359991d12c7708804fe8dd1f944.tar.zst
dexon-af8f5f0b69f1c359991d12c7708804fe8dd1f944.zip
ethstate => state
Diffstat (limited to 'state')
-rw-r--r--state/dump.go47
-rw-r--r--state/errors.go23
-rw-r--r--state/log.go38
-rw-r--r--state/manifest.go55
-rw-r--r--state/state.go321
-rw-r--r--state/state_object.go339
-rw-r--r--state/state_test.go36
7 files changed, 859 insertions, 0 deletions
diff --git a/state/dump.go b/state/dump.go
new file mode 100644
index 000000000..de356f476
--- /dev/null
+++ b/state/dump.go
@@ -0,0 +1,47 @@
+package state
+
+import (
+ "encoding/json"
+ "fmt"
+
+ "github.com/ethereum/go-ethereum/ethutil"
+)
+
+type Account struct {
+ Balance string `json:"balance"`
+ Nonce uint64 `json:"nonce"`
+ CodeHash string `json:"codeHash"`
+ Storage map[string]string `json:"storage"`
+}
+
+type World struct {
+ Root string `json:"root"`
+ Accounts map[string]Account `json:"accounts"`
+}
+
+func (self *State) Dump() []byte {
+ world := World{
+ Root: ethutil.Bytes2Hex(self.Trie.Root.([]byte)),
+ Accounts: make(map[string]Account),
+ }
+
+ self.Trie.NewIterator().Each(func(key string, value *ethutil.Value) {
+ stateObject := NewStateObjectFromBytes([]byte(key), value.Bytes())
+
+ account := Account{Balance: stateObject.balance.String(), Nonce: stateObject.Nonce, CodeHash: ethutil.Bytes2Hex(stateObject.codeHash)}
+ account.Storage = make(map[string]string)
+
+ stateObject.EachStorage(func(key string, value *ethutil.Value) {
+ value.Decode()
+ account.Storage[ethutil.Bytes2Hex([]byte(key))] = ethutil.Bytes2Hex(value.Bytes())
+ })
+ world.Accounts[ethutil.Bytes2Hex([]byte(key))] = account
+ })
+
+ json, err := json.MarshalIndent(world, "", " ")
+ if err != nil {
+ fmt.Println("dump err", err)
+ }
+
+ return json
+}
diff --git a/state/errors.go b/state/errors.go
new file mode 100644
index 000000000..5a847d38b
--- /dev/null
+++ b/state/errors.go
@@ -0,0 +1,23 @@
+package state
+
+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}
+}
diff --git a/state/log.go b/state/log.go
new file mode 100644
index 000000000..73039d7ce
--- /dev/null
+++ b/state/log.go
@@ -0,0 +1,38 @@
+package state
+
+import "github.com/ethereum/go-ethereum/ethutil"
+
+type Log struct {
+ Address []byte
+ Topics [][]byte
+ Data []byte
+}
+
+func NewLogFromValue(decoder *ethutil.Value) Log {
+ log := Log{
+ Address: decoder.Get(0).Bytes(),
+ Data: decoder.Get(2).Bytes(),
+ }
+
+ it := decoder.Get(1).NewIterator()
+ for it.Next() {
+ log.Topics = append(log.Topics, it.Value().Bytes())
+ }
+
+ return log
+}
+
+func (self Log) RlpData() interface{} {
+ return []interface{}{self.Address, ethutil.ByteSliceToInterface(self.Topics), self.Data}
+}
+
+type Logs []Log
+
+func (self Logs) RlpData() interface{} {
+ data := make([]interface{}, len(self))
+ for i, log := range self {
+ data[i] = log.RlpData()
+ }
+
+ return data
+}
diff --git a/state/manifest.go b/state/manifest.go
new file mode 100644
index 000000000..21cd04a1a
--- /dev/null
+++ b/state/manifest.go
@@ -0,0 +1,55 @@
+package state
+
+import (
+ "fmt"
+ "math/big"
+)
+
+// 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 {
+ Messages Messages
+}
+
+func NewManifest() *Manifest {
+ m := &Manifest{}
+ m.Reset()
+
+ return m
+}
+
+func (m *Manifest) Reset() {
+ m.Messages = nil
+}
+
+func (self *Manifest) AddMessage(msg *Message) *Message {
+ self.Messages = append(self.Messages, msg)
+
+ return msg
+}
+
+type Messages []*Message
+type Message struct {
+ To, From []byte
+ Input []byte
+ Output []byte
+ Path int
+ Origin []byte
+ Timestamp int64
+ Coinbase []byte
+ Block []byte
+ Number *big.Int
+ Value *big.Int
+
+ ChangedAddresses [][]byte
+}
+
+func (self *Message) AddStorageChange(addr []byte) {
+ self.ChangedAddresses = append(self.ChangedAddresses, addr)
+}
+
+func (self *Message) String() string {
+ return fmt.Sprintf("Message{to: %x from: %x input: %x output: %x origin: %x coinbase: %x block: %x number: %v timestamp: %d path: %d value: %v", self.To, self.From, self.Input, self.Output, self.Origin, self.Coinbase, self.Block, self.Number, self.Timestamp, self.Path, self.Value)
+}
diff --git a/state/state.go b/state/state.go
new file mode 100644
index 000000000..298cf9680
--- /dev/null
+++ b/state/state.go
@@ -0,0 +1,321 @@
+package state
+
+import (
+ "math/big"
+
+ "github.com/ethereum/go-ethereum/ethtrie"
+ "github.com/ethereum/go-ethereum/ethutil"
+ "github.com/ethereum/go-ethereum/logger"
+)
+
+var statelogger = logger.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
+
+ refund map[string]*big.Int
+
+ logs Logs
+}
+
+// Create a new state from a given trie
+func New(trie *ethtrie.Trie) *State {
+ return &State{Trie: trie, stateObjects: make(map[string]*StateObject), manifest: NewManifest(), refund: make(map[string]*big.Int)}
+}
+
+func (self *State) EmptyLogs() {
+ self.logs = nil
+}
+
+func (self *State) AddLog(log Log) {
+ self.logs = append(self.logs, log)
+}
+
+func (self *State) Logs() Logs {
+ return self.logs
+}
+
+// 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.balance
+ }
+
+ return ethutil.Big0
+}
+
+func (self *State) Refund(addr []byte, gas, price *big.Int) {
+ amount := new(big.Int).Mul(gas, price)
+
+ if self.refund[string(addr)] == nil {
+ self.refund[string(addr)] = new(big.Int)
+ }
+
+ self.refund[string(addr)] = new(big.Int).Add(self.refund[string(addr)], amount)
+}
+
+func (self *State) AddBalance(addr []byte, amount *big.Int) {
+ stateObject := self.GetStateObject(addr)
+ if stateObject != nil {
+ stateObject.AddBalance(amount)
+ }
+}
+
+func (self *State) GetNonce(addr []byte) uint64 {
+ stateObject := self.GetStateObject(addr)
+ if stateObject != nil {
+ return stateObject.Nonce
+ }
+
+ return 0
+}
+
+func (self *State) SetNonce(addr []byte, nonce uint64) {
+ stateObject := self.GetStateObject(addr)
+ if stateObject != nil {
+ stateObject.Nonce = nonce
+ }
+}
+
+func (self *State) GetCode(addr []byte) []byte {
+ stateObject := self.GetStateObject(addr)
+ if stateObject != nil {
+ return stateObject.Code
+ }
+
+ return nil
+}
+
+func (self *State) GetState(a, b []byte) []byte {
+ stateObject := self.GetStateObject(a)
+ if stateObject != nil {
+ return stateObject.GetState(b).Bytes()
+ }
+
+ return nil
+}
+
+func (self *State) SetState(addr, key []byte, value interface{}) {
+ stateObject := self.GetStateObject(addr)
+ if stateObject != nil {
+ stateObject.SetState(key, ethutil.NewValue(value))
+ }
+}
+
+func (self *State) Delete(addr []byte) bool {
+ stateObject := self.GetStateObject(addr)
+ if stateObject != nil {
+ stateObject.MarkForDeletion()
+
+ return true
+ }
+
+ return false
+}
+
+//
+// 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()
+
+ if len(stateObject.CodeHash()) > 0 {
+ ethutil.Config.Db.Put(stateObject.CodeHash(), stateObject.Code)
+ }
+
+ self.Trie.Update(string(addr), string(stateObject.RlpEncode()))
+}
+
+// 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.SetStateObject(stateObject)
+
+ return stateObject
+}
+
+func (self *State) SetStateObject(object *StateObject) {
+ self.stateObjects[string(object.address)] = object
+}
+
+// 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.Debugf("(+) %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 := New(self.Trie.Copy())
+ for k, stateObject := range self.stateObjects {
+ state.stateObjects[k] = stateObject.Copy()
+ }
+
+ for addr, refund := range self.refund {
+ state.refund[addr] = refund
+ }
+
+ logs := make(Logs, len(self.logs))
+ copy(logs, self.logs)
+ state.logs = logs
+
+ 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
+ self.refund = state.refund
+ self.logs = state.logs
+}
+
+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 {
+ if stateObject.State == nil {
+ continue
+ }
+
+ stateObject.State.Sync()
+ }
+
+ s.Trie.Sync()
+
+ s.Empty()
+}
+
+func (self *State) Empty() {
+ self.stateObjects = make(map[string]*StateObject)
+ self.refund = make(map[string]*big.Int)
+}
+
+func (self *State) Update() {
+ var deleted bool
+
+ // Refund any gas that's left
+ for addr, amount := range self.refund {
+ self.GetStateObject([]byte(addr)).AddBalance(amount)
+ }
+
+ for _, stateObject := range self.stateObjects {
+ if stateObject.remove {
+ self.DeleteStateObject(stateObject)
+ deleted = true
+ } else {
+ stateObject.Sync()
+
+ self.UpdateStateObject(stateObject)
+ }
+ }
+
+ // FIXME trie delete is broken
+ if deleted {
+ 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
+ }
+ }
+}
+
+func (self *State) Manifest() *Manifest {
+ return self.manifest
+}
+
+// Debug stuff
+func (self *State) CreateOutputForDiff() {
+ for _, stateObject := range self.stateObjects {
+ stateObject.CreateOutputForDiff()
+ }
+}
diff --git a/state/state_object.go b/state/state_object.go
new file mode 100644
index 000000000..fb568e543
--- /dev/null
+++ b/state/state_object.go
@@ -0,0 +1,339 @@
+package state
+
+import (
+ "fmt"
+ "math/big"
+
+ "github.com/ethereum/go-ethereum/crypto"
+ "github.com/ethereum/go-ethereum/ethtrie"
+ "github.com/ethereum/go-ethereum/ethutil"
+)
+
+type Code []byte
+
+func (self Code) String() string {
+ return string(self) //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
+ balance *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()
+}
+
+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, balance: new(big.Int), gasPool: new(big.Int)}
+ object.State = New(ethtrie.New(ethutil.Config.Db, ""))
+ object.storage = make(Storage)
+ object.gasPool = new(big.Int)
+
+ return object
+}
+
+func NewContract(address []byte, balance *big.Int, root []byte) *StateObject {
+ contract := NewStateObject(address)
+ contract.balance = balance
+ contract.State = New(ethtrie.New(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.balance)
+}
+
+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.GetState(key.Bytes())
+}
+func (self *StateObject) SetStorage(key *big.Int, value *ethutil.Value) {
+ self.SetState(key.Bytes(), value)
+}
+
+func (self *StateObject) Storage() map[string]*ethutil.Value {
+ return self.storage
+}
+
+func (self *StateObject) GetState(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
+}
+
+func (self *StateObject) SetState(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) AddBalance(amount *big.Int) {
+ c.SetBalance(new(big.Int).Add(c.balance, amount))
+
+ statelogger.Debugf("%x: #%d %v (+ %v)\n", c.Address(), c.Nonce, c.balance, amount)
+}
+func (c *StateObject) AddAmount(amount *big.Int) { c.AddBalance(amount) }
+
+func (c *StateObject) SubBalance(amount *big.Int) {
+ c.SetBalance(new(big.Int).Sub(c.balance, amount))
+
+ statelogger.Debugf("%x: #%d %v (- %v)\n", c.Address(), c.Nonce, c.balance, amount)
+}
+func (c *StateObject) SubAmount(amount *big.Int) { c.SubBalance(amount) }
+
+func (c *StateObject) SetBalance(amount *big.Int) {
+ c.balance = amount
+}
+
+func (self *StateObject) Balance() *big.Int { return self.balance }
+
+//
+// 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.balance) > 0 {
+ return fmt.Errorf("insufficient amount: %v, %v", c.balance, 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.balance.Sub(self.balance, rGas)
+}
+
+func (self *StateObject) Copy() *StateObject {
+ stateObject := NewStateObject(self.Address())
+ stateObject.balance.Set(self.balance)
+ 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)
+ stateObject.remove = self.remove
+
+ return stateObject
+}
+
+func (self *StateObject) Set(stateObject *StateObject) {
+ *self = *stateObject
+}
+
+//
+// Attribute accessors
+//
+
+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
+}
+
+// To satisfy ClosureRef
+func (self *StateObject) Object() *StateObject {
+ return self
+}
+
+// Debug stuff
+func (self *StateObject) CreateOutputForDiff() {
+ fmt.Printf("%x %x %x %x\n", self.Address(), self.State.Root(), self.balance.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.balance, root, c.CodeHash()})
+}
+
+func (c *StateObject) CodeHash() ethutil.Bytes {
+ var codeHash []byte
+ if len(c.Code) > 0 {
+ codeHash = crypto.Sha3(c.Code)
+ }
+
+ return codeHash
+}
+
+func (c *StateObject) RlpDecode(data []byte) {
+ decoder := ethutil.NewValueFromBytes(data)
+
+ c.Nonce = decoder.Get(0).Uint()
+ c.balance = decoder.Get(1).BigInt()
+ c.State = New(ethtrie.New(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
+}
diff --git a/state/state_test.go b/state/state_test.go
new file mode 100644
index 000000000..42f434ef0
--- /dev/null
+++ b/state/state_test.go
@@ -0,0 +1,36 @@
+package state
+
+import (
+ "testing"
+
+ "github.com/ethereum/go-ethereum/ethdb"
+ "github.com/ethereum/go-ethereum/ethtrie"
+ "github.com/ethereum/go-ethereum/ethutil"
+)
+
+var ZeroHash256 = make([]byte, 32)
+
+func TestSnapshot(t *testing.T) {
+ db, _ := ethdb.NewMemDatabase()
+ ethutil.ReadConfig(".ethtest", "/tmp/ethtest", "")
+ ethutil.Config.Db = db
+
+ state := New(ethtrie.New(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)
+ }
+}