#define TRY(x) do { int ret = x; if (ret != SP_OK) RETURN_CODEVAL(ret); } while (0)
/* Helper functions. */
-static struct sp_port **list_append(struct sp_port **list, const char *portname);
static enum sp_return get_config(struct sp_port *port, struct port_data *data,
struct sp_port_config *config);
static enum sp_return set_config(struct sp_port *port, struct port_data *data,