pub unsafe extern "C" fn rd_kafka_topic_conf_set_partitioner_cb( topic_conf: *mut rd_kafka_topic_conf_t, partitioner: Option<unsafe extern "C" fn(rkt: *const rd_kafka_topic_t, keydata: *const c_void, keylen: size_t, partition_cnt: i32, rkt_opaque: *mut c_void, msg_opaque: *mut c_void) -> i32>)