///<inheritdoc />
public ITransferResult TransferFunds(ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer, TransferFundsToContract contractDetails)
{
this.logger.LogTrace("({0}:{1},{2}:{3})", nameof(addressTo), addressTo, nameof(amountToTransfer), amountToTransfer);
// TODO: Spend BaseFee here
var balance = smartContractState.GetBalance();
if (balance < amountToTransfer)
{
this.logger.LogTrace("(-)[INSUFFICIENT_BALANCE]:{0}={1}", nameof(balance), balance);
throw new InsufficientBalanceException();
}
// Discern whether this is a contract or an ordinary address.
byte[] contractCode = this.contractStateRepository.GetCode(addressTo.ToUint160(this.network));
if (contractCode == null || contractCode.Length == 0)
{
this.internalTransferList.Add(new TransferInfo
{
From = smartContractState.Message.ContractAddress.ToUint160(this.network),
To = addressTo.ToUint160(this.network),
Value = amountToTransfer
});
this.logger.LogTrace("(-)[TRANSFER_TO_SENDER]:Transfer {0} from {1} to {2}.", smartContractState.Message.ContractAddress, addressTo, amountToTransfer);
return(TransferResult.Empty());
}
this.logger.LogTrace("(-)[TRANSFER_TO_CONTRACT]");
return(ExecuteTransferFundsToContract(contractCode, smartContractState, addressTo, amountToTransfer, contractDetails));
}
///<inheritdoc />
public ITransferResult Transfer(ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer)
{
this.logger.LogTrace("({0}:{1},{2}:{3})", nameof(addressTo), addressTo, nameof(amountToTransfer), amountToTransfer);
// TODO: Spend BaseFee here
EnsureContractHasEnoughBalance(smartContractState, amountToTransfer);
// Discern whether this is a contract or an ordinary address.
byte[] contractCode = this.contractStateRepository.GetCode(addressTo.ToUint160(this.network));
if (contractCode == null || contractCode.Length == 0)
{
this.internalTransferList.Add(new TransferInfo
{
From = smartContractState.Message.ContractAddress.ToUint160(this.network),
To = addressTo.ToUint160(this.network),
Value = amountToTransfer
});
this.logger.LogTrace("(-)[TRANSFER_TO_SENDER]:Transfer {0} from {1} to {2}.", smartContractState.Message.ContractAddress, addressTo, amountToTransfer);
return(TransferResult.Empty());
}
this.logger.LogTrace("(-)[TRANSFER_TO_CONTRACT]");
// Calling a receive handler:
string methodName = MethodCall.ExternalReceiveHandlerName;
object[] parameters = new object[] { };
ulong gasBudget = DefaultGasLimit; // for Transfer always send limited gas to prevent re-entrance.
return(ExecuteTransferFundsToContract(contractCode, smartContractState, addressTo, amountToTransfer, methodName, parameters, gasBudget));
}
///<inheritdoc />
public ITransferResult Call(
ISmartContractState smartContractState,
Address addressTo,
ulong amountToTransfer,
string methodName,
object[] parameters,
ulong gasLimit = 0)
{
// For a method call, send all the gas unless an amount was selected.Should only call trusted methods so re - entrance is less problematic.
ulong gasBudget = (gasLimit != 0) ? gasLimit : smartContractState.GasMeter.GasAvailable;
var message = new InternalCallMessage(
addressTo.ToUint160(this.network),
smartContractState.Message.ContractAddress.ToUint160(this.network),
amountToTransfer,
(Gas)gasBudget,
new MethodCall(methodName, parameters)
);
var result = this.state.Apply(message);
return(result.IsSuccess
? TransferResult.Transferred(result.Success.ExecutionResult)
: TransferResult.Failed());
}
/// <summary>
/// Constructs a result when a transfer from a contract succeeded.
/// </summary>
/// <param name="returnValue">The object that was returned from the executor.</param>
public static TransferResult Transferred(object returnValue)
{
var result = new TransferResult
{
ReturnValue = returnValue
};
return(result);
}
/// <summary>
/// Constructs a result when a transfer from a contract failed.
/// </summary>
/// <param name="thrownException">The exception that was thrown by the executor.</param>
public static TransferResult Failed(Exception thrownException)
{
var result = new TransferResult
{
ThrownException = thrownException
};
return(result);
}
/// <summary>
/// If the address to where the funds will be tranferred to is a contract, instantiate and execute it.
/// </summary>
private ITransferResult ExecuteTransferFundsToContract(byte[] contractCode, ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer, TransferFundsToContract contractDetails)
{
this.logger.LogTrace("({0}:{1},{2}:{3})", nameof(addressTo), addressTo, nameof(amountToTransfer), amountToTransfer);
ulong gasBudget = contractDetails.GasBudget == 0 ? DefaultGasLimit : contractDetails.GasBudget;
// Ensure we have enough gas left to be able to fund the new GasMeter.
if (smartContractState.GasMeter.GasAvailable < gasBudget)
{
throw new InsufficientGasException();
}
var nestedGasMeter = new GasMeter((Gas)gasBudget);
IContractStateRepository track = this.contractStateRepository.StartTracking();
var callData = new CallData(smartContractState.GasMeter.GasLimit, addressTo.ToUint160(this.network), contractDetails.ContractMethodName, contractDetails.MethodParameters);
var context = new TransactionContext(
this.transactionContext.TransactionHash,
this.transactionContext.BlockHeight,
this.transactionContext.Coinbase,
smartContractState.Message.ContractAddress.ToUint160(this.network),
amountToTransfer,
this.transactionContext.GetNonceAndIncrement());
VmExecutionResult result = this.vm.ExecuteMethod(nestedGasMeter,
track,
callData,
context);
// Update parent gas meter.
smartContractState.GasMeter.Spend(nestedGasMeter.GasConsumed);
var revert = result.ExecutionException != null;
if (revert)
{
track.Rollback();
return(TransferResult.Failed(result.ExecutionException));
}
track.Commit();
this.internalTransferList.Add(new TransferInfo
{
From = smartContractState.Message.ContractAddress.ToUint160(this.network),
To = addressTo.ToUint160(this.network),
Value = amountToTransfer
});
this.logger.LogTrace("(-)");
return(TransferResult.Transferred(result.Result));
}
///<inheritdoc />
public ITransferResult Call(
ISmartContractState smartContractState,
Address addressTo,
ulong amountToTransfer,
string methodName,
object[] parameters,
ulong gasLimit = 0)
{
Gas gasRemaining = smartContractState.GasMeter.GasAvailable;
// For a method call, send all the gas unless an amount was selected.Should only call trusted methods so re - entrance is less problematic.
ulong gasBudget = (gasLimit != 0) ? gasLimit : gasRemaining;
if (gasRemaining < gasBudget || gasRemaining < GasPriceList.BaseCost)
{
return(TransferResult.Failed());
}
var message = new InternalCallMessage(
addressTo.ToUint160(this.network),
smartContractState.Message.ContractAddress.ToUint160(this.network),
amountToTransfer,
(Gas)gasBudget,
new MethodCall(methodName, parameters)
);
// Create a snapshot of the current state
IState newState = this.state.Snapshot();
// Apply the message to the snapshot
StateTransitionResult result = this.stateProcessor.Apply(newState, message);
// Transition the current state to the new state
if (result.IsSuccess)
{
this.state.TransitionTo(newState);
}
smartContractState.GasMeter.Spend(result.GasConsumed);
return(result.IsSuccess
? TransferResult.Transferred(result.Success.ExecutionResult)
: TransferResult.Failed());
}
/// <summary>
/// If the address to where the funds will be tranferred to is a contract, instantiate and execute it.
/// </summary>
private ITransferResult ExecuteTransferFundsToContract(byte[] contractCode, ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer, TransferFundsToContract contractDetails)
{
this.logger.LogTrace("({0}:{1},{2}:{3})", nameof(addressTo), addressTo, nameof(amountToTransfer), amountToTransfer);
IContractStateRepository track = this.contractStateRepository.StartTracking();
IPersistenceStrategy persistenceStrategy = new MeteredPersistenceStrategy(track, smartContractState.GasMeter, this.keyEncodingStrategy);
IPersistentState newPersistentState = new PersistentState(persistenceStrategy, addressTo.ToUint160(this.network), this.network);
var newMessage = new Message(addressTo, smartContractState.Message.ContractAddress, amountToTransfer, (Gas)(smartContractState.Message.GasLimit - smartContractState.GasMeter.GasConsumed));
ISmartContractExecutionContext newContext = new SmartContractExecutionContext(smartContractState.Block, newMessage, addressTo.ToUint160(this.network), 0, contractDetails.MethodParameters);
ISmartContractVirtualMachine vm = new ReflectionVirtualMachine(new InternalTransactionExecutorFactory(this.keyEncodingStrategy, this.loggerFactory, this.network), this.loggerFactory);
var result = vm.ExecuteMethod(
contractCode,
contractDetails.ContractMethodName,
newContext,
smartContractState.GasMeter,
newPersistentState,
track);
var revert = result.ExecutionException != null;
if (revert)
{
track.Rollback();
return(TransferResult.Failed(result.ExecutionException));
}
track.Commit();
this.internalTransferList.Add(new TransferInfo
{
From = smartContractState.Message.ContractAddress.ToUint160(this.network),
To = addressTo.ToUint160(this.network),
Value = amountToTransfer
});
this.logger.LogTrace("(-)");
return(TransferResult.Transferred(result.Result));
}
///<inheritdoc />
public ITransferResult Transfer(ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer)
{
this.logger.LogTrace("({0}:{1},{2}:{3})", nameof(addressTo), addressTo, nameof(amountToTransfer), amountToTransfer);
ulong gasBudget = DefaultGasLimit; // for Transfer always send limited gas to prevent re-entrance.
var message = new ContractTransferMessage(
addressTo.ToUint160(this.network),
smartContractState.Message.ContractAddress.ToUint160(this.network),
amountToTransfer,
(Gas)gasBudget
);
var result = this.state.Apply(message);
return(result.IsSuccess
? TransferResult.Empty()
: TransferResult.Failed());
}
/// <summary>
/// If the address to where the funds will be tranferred to is a contract, instantiate and execute it.
/// </summary>
private ITransferResult ExecuteTransferFundsToContract(byte[] contractCode, ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer, TransferFundsToContract contractDetails)
{
this.logger.LogTrace("({0}:{1},{2}:{3})", nameof(addressTo), addressTo, nameof(amountToTransfer), amountToTransfer);
IContractStateRepository track = this.contractStateRepository.StartTracking();
var callData = new CallData(smartContractState.GasMeter.GasLimit, addressTo.ToUint160(this.network), contractDetails.ContractMethodName, contractDetails.MethodParameters);
var context = new TransactionContext(
this.transactionContext.TransactionHash,
this.transactionContext.BlockHeight,
this.transactionContext.Coinbase,
smartContractState.Message.ContractAddress.ToUint160(this.network),
amountToTransfer);
var result = this.vm.ExecuteMethod(smartContractState.GasMeter,
track,
callData,
context);
var revert = result.ExecutionException != null;
if (revert)
{
track.Rollback();
return(TransferResult.Failed(result.ExecutionException));
}
track.Commit();
this.internalTransferList.Add(new TransferInfo
{
From = smartContractState.Message.ContractAddress.ToUint160(this.network),
To = addressTo.ToUint160(this.network),
Value = amountToTransfer
});
this.logger.LogTrace("(-)");
return(TransferResult.Transferred(result.Result));
}
///<inheritdoc />
public ITransferResult Transfer(ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer)
{
this.logger.LogTrace("({0}:{1},{2}:{3})", nameof(addressTo), addressTo, nameof(amountToTransfer), amountToTransfer);
ulong gasBudget = DefaultGasLimit; // for Transfer always send limited gas to prevent re-entrance.
Gas gasRemaining = smartContractState.GasMeter.GasAvailable;
if (gasRemaining < gasBudget || gasRemaining < GasPriceList.BaseCost)
{
return(TransferResult.Failed());
}
var message = new ContractTransferMessage(
addressTo.ToUint160(this.network),
smartContractState.Message.ContractAddress.ToUint160(this.network),
amountToTransfer,
(Gas)gasBudget
);
// Create a snapshot of the current state
IState newState = this.state.Snapshot();
// Apply the message to the snapshot
StateTransitionResult result = this.stateProcessor.Apply(newState, message);
// Transition the current state to the new state
if (result.IsSuccess)
{
this.state.TransitionTo(newState);
}
smartContractState.GasMeter.Spend(result.GasConsumed);
return(result.IsSuccess
? TransferResult.Empty()
: TransferResult.Failed());
}
///<inheritdoc />
public ITransferResult Transfer(ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer)
{
Gas gasRemaining = smartContractState.GasMeter.GasAvailable;
if (gasRemaining < GasPriceList.TransferCost)
{
return(TransferResult.Failed());
}
ulong gasBudget = (gasRemaining < DefaultGasLimit)
? gasRemaining // have enough for at least a transfer but not for the DefaultGasLimit
: DefaultGasLimit; // have enough for anything
var message = new ContractTransferMessage(
addressTo.ToUint160(),
smartContractState.Message.ContractAddress.ToUint160(),
amountToTransfer,
(Gas)gasBudget
);
// Create a snapshot of the current state
IState newState = this.state.Snapshot();
// Apply the message to the snapshot
StateTransitionResult result = this.stateProcessor.Apply(newState, message);
// Transition the current state to the new state
if (result.IsSuccess)
{
this.state.TransitionTo(newState);
}
smartContractState.GasMeter.Spend(result.GasConsumed);
return(result.IsSuccess
? TransferResult.Empty()
: TransferResult.Failed());
}
///<inheritdoc />
public ITransferResult Call(
ISmartContractState smartContractState,
Address addressTo,
ulong amountToTransfer,
string methodName,
object[] parameters,
ulong gasLimit = 0)
{
// TODO: Spend BaseFee here
EnsureContractHasEnoughBalance(smartContractState, amountToTransfer);
byte[] contractCode = this.contractStateRepository.GetCode(addressTo.ToUint160(this.network));
if (contractCode == null || contractCode.Length == 0)
{
return(TransferResult.Empty());
}
// Here, we know contract has code, so we execute it
// For a method call, send all the gas unless an amount was selected.Should only call trusted methods so re - entrance is less problematic.
ulong gasBudget = (gasLimit != 0) ? gasLimit : smartContractState.GasMeter.GasAvailable;
return(ExecuteTransferFundsToContract(contractCode, smartContractState, addressTo, amountToTransfer, methodName, parameters, gasBudget));
}