code: func (h Secretservice) Get(serverURL string) (string, string, error) {
  	if serverURL == "" {
  		return "", "", errors.New("missing server url")
  	}
  	var username *C.char
  	defer C.free(unsafe.Pointer(username))
  	var secret *C.char
  	defer C.free(unsafe.Pointer(secret))
  	server := C.CString(serverURL)
  	defer C.free(unsafe.Pointer(server))
  
  	err := C.get(server, &username, &secret)
  	if err != nil {
  		defer C.g_error_free(err)
  		errMsg := (*C.char)(unsafe.Pointer(err.message))
  		return "", "", errors.New(C.GoString(errMsg))
  	}
  	user := C.GoString(username)
  	pass := C.GoString(secret)
  	if pass == "" {
  		return "", "", credentials.NewErrCredentialsNotFound()
  	}
  	return user, pass, nil
  }
docs: // Get returns the username and secret to use for a given registry server URL.