void datafeed_in(const struct sr_dev_inst *sdi,
const struct sr_datafeed_packet *packet, void *cb_data);
int opt_to_gvar(char *key, char *value, struct sr_config *src);
void datafeed_in(const struct sr_dev_inst *sdi,
const struct sr_datafeed_packet *packet, void *cb_data);
int opt_to_gvar(char *key, char *value, struct sr_config *src);