Supply live tracer

cmd/geth/config.go

@@ -181,7 +181,15 @@ func makeFullNode(ctx *cli.Context) (*node.Node, ethapi.Backend) {
 
 	if ctx.IsSet(utils.VMTraceFlag.Name) {
 		if name := ctx.String(utils.VMTraceFlag.Name); name != "" {
-			t, err := directory.LiveDirectory.New(name)
+			liveTracerCtx := directory.LiveTracerContext{}
+
+			if ctx.IsSet(utils.VMTracePathFlag.Name) {
+				if path := ctx.String(utils.VMTracePathFlag.Name); path != "" {
+					liveTracerCtx.OutputPath = path
+				}
+			}
+
+			t, err := directory.LiveDirectory.New(name, &liveTracerCtx)
 			if err != nil {
 				utils.Fatalf("Failed to create tracer %q: %v", name, err)
 			}

cmd/utils/flags.go

@@ -502,6 +502,12 @@ var (
 		Usage:    "Name of tracer which should record internal VM operations (costly)",
 		Category: flags.VMCategory,
 	}
+	VMTracePathFlag = &flags.DirectoryFlag{
+		Name:     "vmtrace.output.path",
+		Usage:    "Directory to store VM traces in",
+		Value:    flags.DirectoryString("."),
+		Category: flags.VMCategory,
+	}
 
 	// API options.
 	RPCGlobalGasCapFlag = &cli.Uint64Flag{
@@ -2128,7 +2134,15 @@ func MakeChain(ctx *cli.Context, stack *node.Node, readonly bool) (*core.BlockCh
 	vmcfg := vm.Config{EnablePreimageRecording: ctx.Bool(VMEnableDebugFlag.Name)}
 	if ctx.IsSet(VMTraceFlag.Name) {
 		if name := ctx.String(VMTraceFlag.Name); name != "" {
-			t, err := directory.LiveDirectory.New(name)
+			liveTracerCtx := directory.LiveTracerContext{}
+
+			if ctx.IsSet(VMTracePathFlag.Name) {
+				if path := ctx.String(VMTracePathFlag.Name); path != "" {
+					liveTracerCtx.OutputPath = path
+				}
+			}
+
+			t, err := directory.LiveDirectory.New(name, &liveTracerCtx)
 			if err != nil {
 				Fatalf("Failed to create tracer %q: %v", name, err)
 			}

core/state/metadata.go

@@ -48,7 +48,7 @@ const (
 	// BalanceDecreaseDaoAccount is ether taken from a DAO account to be moved to the refund contract.
 	BalanceDecreaseDaoAccount BalanceChangeReason = 9
 
-	// BalanceChangeTransfer is ether transfered via a call.
+	// BalanceChangeTransfer is ether transferred via a call.
 	// it is a decrease for the sender and an increase for the recipient.
 	BalanceChangeTransfer BalanceChangeReason = 10
 	// BalanceChangeTouchAccount is a transfer of zero value. It is only there to
@@ -64,3 +64,42 @@ const (
 	// Note it doesn't account for a self-destruct which appoints itself as recipient.
 	BalanceDecreaseSelfdestructBurn BalanceChangeReason = 14
 )
+
+// TODO: to be removed, it's useful for logs while developing
+// String returns a string representation of the reason.
+func (r BalanceChangeReason) String() string {
+	switch r {
+	case BalanceChangeUnspecified:
+		return "BalanceChangeUnspecified"
+	case BalanceIncreaseRewardMineUncle:
+		return "BalanceIncreaseRewardMineUncle"
+	case BalanceIncreaseRewardMineBlock:
+		return "BalanceIncreaseRewardMineBlock"
+	case BalanceIncreaseWithdrawal:
+		return "BalanceIncreaseWithdrawal"
+	case BalanceIncreaseGenesisBalance:
+		return "BalanceIncreaseGenesisBalance"
+	case BalanceIncreaseRewardTransactionFee:
+		return "BalanceIncreaseRewardTransactionFee"
+	case BalanceDecreaseGasBuy:
+		return "BalanceDecreaseGasBuy"
+	case BalanceIncreaseGasReturn:
+		return "BalanceIncreaseGasReturn"
+	case BalanceIncreaseDaoContract:
+		return "BalanceIncreaseDaoContract"
+	case BalanceDecreaseDaoAccount:
+		return "BalanceDecreaseDaoAccount"
+	case BalanceChangeTransfer:
+		return "BalanceChangeTransfer"
+	case BalanceChangeTouchAccount:
+		return "BalanceChangeTouchAccount"
+	case BalanceIncreaseSelfdestruct:
+		return "BalanceIncreaseSelfdestruct"
+	case BalanceDecreaseSelfdestruct:
+		return "BalanceDecreaseSelfdestruct"
+	case BalanceDecreaseSelfdestructBurn:
+		return "BalanceDecreaseSelfdestructBurn"
+	default:
+		return "unknown"
+	}
+}

eth/tracers/directory/live.go

@@ -6,7 +6,12 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 )
 
-type ctorFunc func() (core.BlockchainLogger, error)
+// Context contains some contextual infos to support the live tracers.
+type LiveTracerContext struct {
+	OutputPath string
+}
+
+type ctorFunc func(ctx *LiveTracerContext) (core.BlockchainLogger, error)
 
 // LiveDirectory is the collection of tracers which can be used
 // during normal block import operations.
@@ -22,9 +27,9 @@ func (d *liveDirectory) Register(name string, f ctorFunc) {
 }
 
 // New instantiates a tracer by name.
-func (d *liveDirectory) New(name string) (core.BlockchainLogger, error) {
+func (d *liveDirectory) New(name string, ctx *LiveTracerContext) (core.BlockchainLogger, error) {
 	if f, ok := d.elems[name]; ok {
-		return f()
+		return f(ctx)
 	}
 	return nil, errors.New("not found")
 }