package ethchain import ( "fmt" "github.com/ethereum/eth-go/ethutil" "math/big" ) type StateObject struct { // Address of the object address []byte // Shared attributes Amount *big.Int Nonce uint64 // Contract related attributes state *State script []byte initScript []byte } // 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() { // FIXME addr := tx.Hash()[12:] value := tx.Value contract := NewContract(addr, value, []byte("")) state.UpdateStateObject(contract) contract.script = tx.Data contract.initScript = tx.Init state.UpdateStateObject(contract) return contract } return nil } func NewContract(address []byte, Amount *big.Int, root []byte) *StateObject { contract := &StateObject{address: address, Amount: Amount, Nonce: 0} contract.state = NewState(ethutil.NewTrie(ethutil.Config.Db, string(root))) return contract } // Returns a newly created account func NewAccount(address []byte, amount *big.Int) *StateObject { account := &StateObject{address: address, Amount: amount, Nonce: 0} return account } func NewStateObjectFromBytes(address, data []byte) *StateObject { object := &StateObject{address: address} object.RlpDecode(data) return object } func (c *StateObject) State() *State { return c.state } func (c *StateObject) Addr(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 (c *StateObject) SetMem(num *big.Int, val *ethutil.Value) { addr := ethutil.BigToBytes(num, 256) c.SetAddr(addr, val) //c.state.trie.Update(string(addr), string(val.Encode())) } func (c *StateObject) GetMem(num *big.Int) *ethutil.Value { nb := ethutil.BigToBytes(num, 256) return c.Addr(nb) } func (c *StateObject) GetInstr(pc *big.Int) *ethutil.Value { if int64(len(c.script)-1) < pc.Int64() { return ethutil.NewValue(0) } return ethutil.NewValueFromBytes([]byte{c.script[pc.Int64()]}) } // Return the gas back to the origin. Used by the Virtual machine or Closures func (c *StateObject) ReturnGas(gas, price *big.Int, state *State) { remainder := new(big.Int).Mul(gas, price) c.AddAmount(remainder) } func (c *StateObject) AddAmount(amount *big.Int) { c.SetAmount(new(big.Int).Add(c.Amount, amount)) } func (c *StateObject) SubAmount(amount *big.Int) { c.SetAmount(new(big.Int).Sub(c.Amount, amount)) } func (c *StateObject) SetAmount(amount *big.Int) { c.Amount = amount } 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 } // Returns the address of the contract/account func (c *StateObject) Address() []byte { return c.address } // Returns the main script body func (c *StateObject) Script() []byte { return c.script } // Returns the initialization script func (c *StateObject) Init() []byte { return c.initScript } // State object encoding methods func (c *StateObject) RlpEncode() []byte { var root interface{} if c.state != nil { root = c.state.trie.Root } else { root = nil } return ethutil.Encode([]interface{}{c.Amount, c.Nonce, root, c.script}) } func (c *StateObject) RlpDecode(data []byte) { decoder := ethutil.NewValueFromBytes(data) c.Amount = decoder.Get(0).BigInt() c.Nonce = decoder.Get(1).Uint() c.state = NewState(ethutil.NewTrie(ethutil.Config.Db, decoder.Get(2).Interface())) c.script = decoder.Get(3).Bytes() } // The cached state and state object cache are helpers which will give you somewhat // control over the nonce. When creating new transactions you're interested in the 'next' // nonce rather than the current nonce. This to avoid creating invalid-nonce transactions. type StateObjectCache struct { cachedObjects map[string]*CachedStateObject } func NewStateObjectCache() *StateObjectCache { return &StateObjectCache{cachedObjects: make(map[string]*CachedStateObject)} } func (s *StateObjectCache) Add(addr []byte, object *StateObject) *CachedStateObject { state := &CachedStateObject{Nonce: object.Nonce, Object: object} s.cachedObjects[string(addr)] = state return state } func (s *StateObjectCache) Get(addr []byte) *CachedStateObject { return s.cachedObjects[string(addr)] } type CachedStateObject struct { Nonce uint64 Object *StateObject }