fix

ndniptunnel/mNetIO.cpp

@@ -46,7 +46,9 @@ int MNetIO::sendData(char *buf, int size, char *name) {
     // Create Data packet
     auto data = make_shared<Data>(dataName);
     data->setFreshnessPeriod(0_s);
-    data->setContent(reinterpret_cast<const uint8_t *>(buf), size);
+    if (size > 0) {
+        data->setContent(reinterpret_cast<const uint8_t *>(buf), size);
+    }
 
     string dsha = "id:/localhost/identity/digest-sha256";
     ndn::security::SigningInfo si(dsha);

ndniptunnel/main.go

@@ -88,7 +88,11 @@ func sendInterest(name string) error {
 //int sendData(char *buf, int size, char *name) ;
 func sendData(pkt []byte, name string) error {
 	cstr := C.CString(name)
-	C.sendData((*C.char)(unsafe.Pointer(&pkt[0])), C.int(len(pkt)), cstr)
+	if pkt == nil {
+		C.sendData((*C.char)(unsafe.Pointer(nil)), C.int(0), cstr)
+	} else {
+		C.sendData((*C.char)(unsafe.Pointer(&pkt[0])), C.int(len(pkt)), cstr)
+	}
 	C.free(unsafe.Pointer(cstr))
 	return nil
 }