path: root/state/state_object.go

package state

import (
    "bytes"
    "fmt"
    "math/big"

    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/crypto"
    "github.com/ethereum/go-ethereum/rlp"
    "github.com/ethereum/go-ethereum/trie"
)

type Code []byte

func (self Code) String() string {
    return string(self) //strings.Join(Disassemble(self), " ")
}

type Storage map[string]*common.Value

func (self Storage) String() (str string) {
    for key, value := range self {
        str += fmt.Sprintf("%X : %X\n", key, value.Bytes())
    }

    return
}

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 {
    // State database for storing state changes
    db common.Database
    // The state object
    State *StateDB

    // Address belonging to this account
    address common.Address
    // The balance of the account
    balance *big.Int
    // The nonce of the account
    nonce uint64
    // The code hash if code is present (i.e. a contract)
    codeHash []byte
    // The code for this account
    code Code
    // Temporarily initialisation code
    initCode Code
    // Cached storage (flushed when updated)
    storage Storage
    // Temporary prepaid gas, reward after transition
    prepaid *big.Int

    // 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
    dirty  bool
}

func (self *StateObject) Reset() {
    self.storage = make(Storage)
    self.State.Reset()
}

func NewStateObject(address common.Address, db common.Database) *StateObject {
    // This to ensure that it has 20 bytes (and not 0 bytes), thus left or right pad doesn't matter.
    //address := common.ToAddress(addr)

    object := &StateObject{db: db, address: address, balance: new(big.Int), gasPool: new(big.Int), dirty: true}
    object.State = New(nil, db) //New(trie.New(common.Config.Db, ""))
    object.storage = make(Storage)
    object.gasPool = new(big.Int)
    object.prepaid = new(big.Int)

    return object
}

func NewStateObjectFromBytes(address common.Address, data []byte, db common.Database) *StateObject {
    // TODO clean me up
    var extobject struct {
        Nonce    uint64
        Balance  *big.Int
        Root     common.Hash
        CodeHash []byte
    }
    err := rlp.Decode(bytes.NewReader(data), &extobject)
    if err != nil {
        fmt.Println(err)
        return nil
    }

    object := &StateObject{address: address, db: db}
    //object.RlpDecode(data)
    object.nonce = extobject.Nonce
    object.balance = extobject.Balance
    object.codeHash = extobject.CodeHash
    object.State = New(extobject.Root[:], db)
    object.storage = make(map[string]*common.Value)
    object.gasPool = new(big.Int)
    object.prepaid = new(big.Int)
    object.code, _ = db.Get(extobject.CodeHash)

    return object
}

func (self *StateObject) MarkForDeletion() {
    self.remove = true
    self.dirty = true
    statelogger.Debugf("%x: #%d %v X\n", self.Address(), self.nonce, self.balance)
}

func (c *StateObject) getAddr(addr common.Hash) *common.Value {
    return common.NewValueFromBytes([]byte(c.State.trie.Get(addr[:])))
}

func (c *StateObject) setAddr(addr []byte, value interface{}) {
    c.State.trie.Update(addr, common.Encode(value))
}

func (self *StateObject) GetStorage(key *big.Int) *common.Value {
    return self.GetState(common.BytesToHash(key.Bytes()))
}
func (self *StateObject) SetStorage(key *big.Int, value *common.Value) {
    self.SetState(common.BytesToHash(key.Bytes()), value)
}

func (self *StateObject) Storage() Storage {
    return self.storage
}

func (self *StateObject) GetState(key common.Hash) *common.Value {
    strkey := key.Str()
    value := self.storage[strkey]
    if value == nil {
        value = self.getAddr(key)

        if !value.IsNil() {
            self.storage[strkey] = value
        }
    }

    return value
}

func (self *StateObject) SetState(k common.Hash, value *common.Value) {
    self.storage[k.Str()] = value.Copy()
    self.dirty = true
}

func (self *StateObject) Sync() {
    for key, value := range self.storage {
        if value.Len() == 0 {
            self.State.trie.Delete([]byte(key))
            continue
        }

        self.setAddr([]byte(key), value)
    }
    self.storage = make(Storage)
}

func (c *StateObject) GetInstr(pc *big.Int) *common.Value {
    if int64(len(c.code)-1) < pc.Int64() {
        return common.NewValue(0)
    }

    return common.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) 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) SetBalance(amount *big.Int) {
    c.balance = amount
    c.dirty = true
}

func (c *StateObject) St() Storage {
    return c.storage
}

//
// 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.SubBalance(total)

    c.dirty = true

    return nil
}

func (self *StateObject) SetGasPool(gasLimit *big.Int) {
    self.gasPool = new(big.Int).Set(gasLimit)

    statelogger.Debugf("%x: gas (+ %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)
    }

    self.gasPool.Sub(self.gasPool, gas)

    rGas := new(big.Int).Set(gas)
    rGas.Mul(rGas, price)

    self.dirty = true

    return nil
}

func (self *StateObject) RefundGas(gas, price *big.Int) {
    self.gasPool.Add(self.gasPool, gas)
}

func (self *StateObject) Copy() *StateObject {
    stateObject := NewStateObject(self.Address(), self.db)
    stateObject.balance.Set(self.balance)
    stateObject.codeHash = common.CopyBytes(self.codeHash)
    stateObject.nonce = self.nonce
    if self.State != nil {
        stateObject.State = self.State.Copy()
    }
    stateObject.code = common.CopyBytes(self.code)
    stateObject.initCode = common.CopyBytes(self.initCode)
    stateObject.storage = self.storage.Copy()
    stateObject.gasPool.Set(self.gasPool)
    stateObject.remove = self.remove
    stateObject.dirty = self.dirty

    return stateObject
}

func (self *StateObject) Set(stateObject *StateObject) {
    *self = *stateObject
}

//
// Attribute accessors
//

func (self *StateObject) Balance() *big.Int {
    return self.balance
}

func (c *StateObject) N() *big.Int {
    return big.NewInt(int64(c.nonce))
}

// Returns the address of the contract/account
func (c *StateObject) Address() common.Address {
    return c.address
}

// Returns the initialization Code
func (c *StateObject) Init() Code {
    return c.initCode
}

func (self *StateObject) Trie() *trie.SecureTrie {
    return self.State.trie
}

func (self *StateObject) Root() []byte {
    return self.Trie().Root()
}

func (self *StateObject) Code() []byte {
    return self.code
}

func (self *StateObject) SetCode(code []byte) {
    self.code = code
    self.dirty = true
}

func (self *StateObject) SetInitCode(code []byte) {
    self.initCode = code
    self.dirty = true
}

func (self *StateObject) SetNonce(nonce uint64) {
    self.nonce = nonce
    self.dirty = true
}

func (self *StateObject) Nonce() uint64 {
    return self.nonce
}

//
// Encoding
//

// State object encoding methods
func (c *StateObject) RlpEncode() []byte {
    return common.Encode([]interface{}{c.nonce, c.balance, c.Root(), c.CodeHash()})
}

func (c *StateObject) CodeHash() common.Bytes {
    return crypto.Sha3(c.code)
}

func (c *StateObject) RlpDecode(data []byte) {
    decoder := common.NewValueFromBytes(data)
    c.nonce = decoder.Get(0).Uint()
    c.balance = decoder.Get(1).BigInt()
    c.State = New(decoder.Get(2).Bytes(), c.db) //New(trie.New(common.Config.Db, decoder.Get(2).Interface()))
    c.storage = make(map[string]*common.Value)
    c.gasPool = new(big.Int)

    c.codeHash = decoder.Get(3).Bytes()

    c.code, _ = c.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
}