/// <summary>
/// Applies an internally generated contract creation message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, InternalCreateMessage message)
{
bool enoughBalance = this.EnsureSenderHasEnoughBalance(state, message.From, message.Amount);
if (!enoughBalance)
{
return(StateTransitionResult.Fail((RuntimeObserver.Gas) 0, StateTransitionErrorKind.InsufficientBalance)); // Trivial - just return and let the MethodCall gas account for it.
}
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((RuntimeObserver.Gas)GasPriceList.CreateCost);
byte[] contractCode = state.ContractState.GetCode(message.From);
uint160 address = state.GenerateAddress(this.AddressGenerator);
// For internal creates we need to add the value contained in the contract invocation transaction
// to the internal transfer list. This must occur before we apply the message to the state.
// For external creates we do not need to do this.
state.AddInternalTransfer(new TransferInfo(message.From, address, message.Amount));
StateTransitionResult result = this.ApplyCreate(state, message.Parameters, contractCode, message, address, gasMeter, message.Type);
return(result);
}
private StateTransitionResult ApplyCreate(IState state,
object[] parameters,
byte[] code,
BaseMessage message,
uint160 address,
RuntimeObserver.IGasMeter gasMeter,
string type = null)
{
state.ContractState.CreateAccount(address);
ISmartContractState smartContractState = state.CreateSmartContractState(state, gasMeter, address, message, state.ContractState);
VmExecutionResult result = this.Vm.Create(state.ContractState, smartContractState, gasMeter, code, parameters, type);
bool revert = !result.IsSuccess;
if (revert)
{
return(StateTransitionResult.Fail(
gasMeter.GasConsumed,
result.Error));
}
return(StateTransitionResult.Ok(
gasMeter.GasConsumed,
address,
result.Success.Result
));
}
/// <summary>
/// Applies an internally generated contract funds transfer message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, ContractTransferMessage message)
{
bool enoughBalance = this.EnsureSenderHasEnoughBalance(state, message.From, message.Amount);
if (!enoughBalance)
{
return(StateTransitionResult.Fail((RuntimeObserver.Gas) 0, StateTransitionErrorKind.InsufficientBalance));
}
var gasMeter = new GasMeter(message.GasLimit);
// If it's not a contract, create a regular P2PKH tx
// If it is a contract, do a regular contract call
byte[] contractCode = state.ContractState.GetCode(message.To);
if (contractCode == null || contractCode.Length == 0)
{
gasMeter.Spend((RuntimeObserver.Gas)GasPriceList.TransferCost);
// No contract at this address, create a regular P2PKH xfer
state.AddInternalTransfer(new TransferInfo(message.From, message.To, message.Amount));
return(StateTransitionResult.Ok(gasMeter.GasConsumed, message.To));
}
// For internal contract-contract transfers we need to add the value contained in the contract invocation transaction
// to the internal transfer list. This must occur before we apply the message to the state.
state.AddInternalTransfer(new TransferInfo(message.From, message.To, message.Amount));
gasMeter.Spend((RuntimeObserver.Gas)GasPriceList.BaseCost);
StateTransitionResult result = this.ApplyCall(state, message, contractCode, gasMeter);
return(result);
}
/// <summary>
/// Applies an internally generated contract method call message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, InternalCallMessage message)
{
bool enoughBalance = this.EnsureSenderHasEnoughBalance(state, message.From, message.Amount);
if (!enoughBalance)
{
return(StateTransitionResult.Fail((RuntimeObserver.Gas) 0, StateTransitionErrorKind.InsufficientBalance)); // Trivial - just return and let the MethodCall gas account for it.
}
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((RuntimeObserver.Gas)GasPriceList.BaseCost);
byte[] contractCode = state.ContractState.GetCode(message.To);
if (contractCode == null || contractCode.Length == 0)
{
return(StateTransitionResult.Fail(gasMeter.GasConsumed, StateTransitionErrorKind.NoCode));
}
// For internal calls we need to add the value contained in the contract invocation transaction
// to the internal transfer list. This must occur before we apply the message to the state.
// For external calls we do not need to do this.
state.AddInternalTransfer(new TransferInfo(message.From, message.To, message.Amount));
StateTransitionResult result = this.ApplyCall(state, message, contractCode, gasMeter);
return(result);
}
private StateTransitionResult ApplyCall(IState state, CallMessage message, byte[] contractCode, RuntimeObserver.IGasMeter gasMeter)
{
// This needs to happen after the base fee is charged, which is why it's in here.
// TODO - Remove this check. It isn't possible for the method name to be null.
if (message.Method.Name == null)
{
return(StateTransitionResult.Fail(gasMeter.GasConsumed, StateTransitionErrorKind.NoMethodName));
}
string type = state.ContractState.GetContractType(message.To);
ISmartContractState smartContractState = state.CreateSmartContractState(state, gasMeter, message.To, message, state.ContractState);
VmExecutionResult result = this.Vm.ExecuteMethod(smartContractState, gasMeter, message.Method, contractCode, type);
bool revert = !result.IsSuccess;
if (revert)
{
return(StateTransitionResult.Fail(
gasMeter.GasConsumed,
result.Error));
}
return(StateTransitionResult.Ok(
gasMeter.GasConsumed,
message.To,
result.Success.Result
));
}
private StateTransitionResult ApplyCall(IState state, CallMessage message, byte[] contractCode, ExecutionContext executionContext)
{
// This needs to happen after the base fee is charged, which is why it's in here.
if (message.Method.Name == null)
{
return(StateTransitionResult.Fail(executionContext.GasMeter.GasConsumed, StateTransitionErrorKind.NoMethodName));
}
string type = state.ContractState.GetContractType(message.To);
ISmartContractState smartContractState = state.CreateSmartContractState(state, executionContext.GasMeter, message.To, message, state.ContractState);
VmExecutionResult result = this.Vm.ExecuteMethod(smartContractState, executionContext, message.Method, contractCode, type);
bool revert = !result.IsSuccess;
if (revert)
{
return(StateTransitionResult.Fail(
executionContext.GasMeter.GasConsumed,
result.Error));
}
return(StateTransitionResult.Ok(
executionContext.GasMeter.GasConsumed,
message.To,
result.Success.Result
));
}
///<inheritdoc />
public ITransferResult Call(
ISmartContractState smartContractState,
Address addressTo,
ulong amountToTransfer,
string methodName,
object[] parameters,
ulong gasLimit = 0)
{
Gas gasRemaining = this.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(),
smartContractState.Message.ContractAddress.ToUint160(),
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);
}
this.gasMeter.Spend(result.GasConsumed);
return(result.IsSuccess
? TransferResult.Transferred(result.Success.ExecutionResult)
: TransferResult.Failed());
}
/// <summary>
/// Applies an externally generated contract method call message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, ExternalCallMessage message)
{
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
byte[] contractCode = state.ContractState.GetCode(message.To);
if (contractCode == null || contractCode.Length == 0)
{
return(StateTransitionResult.Fail(gasMeter.GasConsumed, StateTransitionErrorKind.NoCode));
}
// For external calls we need to increment the balance state to take into
// account any funds sent as part of the original contract invocation transaction.
state.AddInitialTransfer(new TransferInfo(message.From, message.To, message.Amount));
return(ApplyCall(state, message, contractCode, gasMeter));
}
///<inheritdoc />
public ICreateResult Create <T>(ISmartContractState smartContractState,
ulong amountToTransfer,
object[] parameters,
ulong gasLimit = 0)
{
Gas gasRemaining = this.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;
Debug.WriteLine("Gas budget:" + gasBudget);
if (gasRemaining < gasBudget || gasRemaining < GasPriceList.CreateCost)
{
return(CreateResult.Failed());
}
var message = new InternalCreateMessage(
smartContractState.Message.ContractAddress.ToUint160(),
amountToTransfer,
(Gas)gasBudget,
parameters,
typeof(T).Name
);
// 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);
}
this.gasMeter.Spend(result.GasConsumed);
return(result.IsSuccess
? CreateResult.Succeeded(result.Success.ContractAddress.ToAddress())
: CreateResult.Failed());
}
///<inheritdoc />
public ITransferResult Transfer(ISmartContractState smartContractState, Address addressTo, ulong amountToTransfer)
{
Gas gasRemaining = this.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);
}
this.gasMeter.Spend(result.GasConsumed);
return(result.IsSuccess
? TransferResult.Empty()
: TransferResult.Failed());
}