add Restore function for inactive accounts

core/evm.go

@@ -47,6 +47,7 @@ func NewEVMContext(msg Message, header *types.Header, chain ChainContext, author
 	return vm.Context{
 		CanTransfer: CanTransfer,
 		Transfer:    Transfer,
+		Restore:     Restore, // restore inactive account function (jmlee)
 		GetHash:     GetHashFn(header, chain),
 		Origin:      msg.From(),
 		Coinbase:    beneficiary,
@@ -95,3 +96,10 @@ func Transfer(db vm.StateDB, sender, recipient common.Address, amount *big.Int)
 	db.SubBalance(sender, amount)
 	db.AddBalance(recipient, amount)
 }
+
+// Restore restores the inactive account (jmlee)
+func Restore(db vm.StateDB, inactiveAddr common.Address, amount *big.Int) {
+	bal := db.GetBalance(inactiveAddr)
+	db.SubBalance(inactiveAddr, bal)
+	db.AddBalance(inactiveAddr, amount)
+}

core/state_transition.go

@@ -208,6 +208,7 @@ func (st *StateTransition) TransitionDb() (ret []byte, usedGas uint64, failed bo
 	if contractCreation {
 		ret, _, st.gas, vmerr = evm.Create(sender, st.data, st.gas, st.value)
 	} else {
+		log.Info("### transfer value TX calls evm.Call()") // (jmlee)
 		// Increment the nonce for the next transaction
 		st.state.SetNonce(msg.From(), st.state.GetNonce(sender.Address())+1)
 		ret, st.gas, vmerr = evm.Call(sender, st.to(), st.data, st.gas, st.value)

core/vm/evm.go

@@ -35,6 +35,8 @@ type (
 	CanTransferFunc func(StateDB, common.Address, *big.Int) bool
 	// TransferFunc is the signature of a transfer function
 	TransferFunc func(StateDB, common.Address, common.Address, *big.Int)
+	// RestoreFunc is the signature of a restore function (jmlee)
+	RestoreFunc func(StateDB, common.Address, *big.Int)
 	// GetHashFunc returns the nth block hash in the blockchain
 	// and is used by the BLOCKHASH EVM op code.
 	GetHashFunc func(uint64) common.Hash
@@ -75,6 +77,8 @@ type Context struct {
 	CanTransfer CanTransferFunc
 	// Transfer transfers ether from one account to the other
 	Transfer TransferFunc
+	// Restore restores the inactive account (jmlee)
+	Restore RestoreFunc
 	// GetHash returns the hash corresponding to n
 	GetHash GetHashFunc
 
@@ -216,7 +220,21 @@ func (evm *EVM) Call(caller ContractRef, addr common.Address, input []byte, gas
 		}
 		evm.StateDB.CreateAccount(addr)
 	}
-	evm.Transfer(evm.StateDB, caller.Address(), to.Address(), value)
+
+	// old version (jmlee)
+	//evm.Transfer(evm.StateDB, caller.Address(), to.Address(), value)
+	// new version (jmlee)
+	if addr == common.HexToAddress("0x1111111111111111111111111111111111111111") {
+		// restoration tx
+		inactiveAddr := common.HexToAddress("0x12345") // temp value for test
+		evm.StateDB.CreateAccount(inactiveAddr)        // temp setting for test
+		amount := big.NewInt(12345)                    // temp value for test
+		evm.Restore(evm.StateDB, inactiveAddr, amount)
+	} else {
+		// value transfer tx
+		evm.Transfer(evm.StateDB, caller.Address(), to.Address(), value)
+	}
+
 	// Initialise a new contract and set the code that is to be used by the EVM.
 	// The contract is a scoped environment for this execution context only.
 	contract := NewContract(caller, to, value, gas)