eth/tracers: make txhash blockhash accessible to native tracers

eth/tracers/native/4byte.go

@@ -55,7 +55,7 @@ type fourByteTracer struct {
 
 // newFourByteTracer returns a native go tracer which collects
 // 4 byte-identifiers of a tx, and implements vm.EVMLogger.
-func newFourByteTracer() tracers.Tracer {
+func newFourByteTracer(ctx *tracers.Context) tracers.Tracer {
 	t := &fourByteTracer{
 		ids: make(map[string]int),
 	}

eth/tracers/native/call.go

@@ -56,7 +56,7 @@ type callTracer struct {
 
 // newCallTracer returns a native go tracer which tracks
 // call frames of a tx, and implements vm.EVMLogger.
-func newCallTracer() tracers.Tracer {
+func newCallTracer(ctx *tracers.Context) tracers.Tracer {
 	// First callframe contains tx context info
 	// and is populated on start and end.
 	return &callTracer{callstack: make([]callFrame, 1)}

eth/tracers/native/noop.go

@@ -35,7 +35,7 @@ func init() {
 type noopTracer struct{}
 
 // newNoopTracer returns a new noop tracer.
-func newNoopTracer() tracers.Tracer {
+func newNoopTracer(ctx *tracers.Context) tracers.Tracer {
 	return &noopTracer{}
 }
 

eth/tracers/native/prestate.go

@@ -51,7 +51,7 @@ type prestateTracer struct {
 	reason    error  // Textual reason for the interruption
 }
 
-func newPrestateTracer() tracers.Tracer {
+func newPrestateTracer(ctx *tracers.Context) tracers.Tracer {
 	// First callframe contains tx context info
 	// and is populated on start and end.
 	return &prestateTracer{prestate: prestate{}}

eth/tracers/native/tracer.go

@@ -45,6 +45,9 @@ func init() {
 	tracers.RegisterLookup(false, lookup)
 }
 
+// ctorFn is the constructor signature of a native tracer.
+type ctorFn = func(*tracers.Context) tracers.Tracer
+
 /*
 ctors is a map of package-local tracer constructors.
 
@@ -57,23 +60,23 @@ The go spec (https://golang.org/ref/spec#Package_initialization) says
 
 Hence, we cannot make the map in init, but must make it upon first use.
 */
-var ctors map[string]func() tracers.Tracer
+var ctors map[string]ctorFn
 
 // register is used by native tracers to register their presence.
-func register(name string, ctor func() tracers.Tracer) {
+func register(name string, ctor ctorFn) {
 	if ctors == nil {
-		ctors = make(map[string]func() tracers.Tracer)
+		ctors = make(map[string]ctorFn)
 	}
 	ctors[name] = ctor
 }
 
 // lookup returns a tracer, if one can be matched to the given name.
 func lookup(name string, ctx *tracers.Context) (tracers.Tracer, error) {
 	if ctors == nil {
-		ctors = make(map[string]func() tracers.Tracer)
+		ctors = make(map[string]ctorFn)
 	}
 	if ctor, ok := ctors[name]; ok {
-		return ctor(), nil
+		return ctor(ctx), nil
 	}
 	return nil, errors.New("no tracer found")
 }