+
+/*
+ * Check if for a given session id there is still data needed to be extract
+ * from the buffers.
+ *
+ * Return 1 if data is in fact available to be read or else 0.
+ */
+int consumer_data_available(uint64_t id)
+{
+ int ret;
+ struct lttng_ht_iter iter;
+ struct lttng_ht *ht;
+ struct lttng_consumer_stream *stream;
+ int (*data_available)(struct lttng_consumer_stream *);
+
+ DBG("Consumer data available command on session id %" PRIu64, id);
+
+ pthread_mutex_lock(&consumer_data.lock);
+
+ switch (consumer_data.type) {
+ case LTTNG_CONSUMER_KERNEL:
+ data_available = lttng_kconsumer_data_available;
+ break;
+ case LTTNG_CONSUMER32_UST:
+ case LTTNG_CONSUMER64_UST:
+ data_available = lttng_ustconsumer_data_available;
+ break;
+ default:
+ ERR("Unknown consumer data type");
+ assert(0);
+ }
+
+ /* Ease our life a bit */
+ ht = consumer_data.stream_list_ht;
+
+ cds_lfht_for_each_entry_duplicate(ht->ht, (long unsigned int) ht->hash_fct,
+ ht->match_fct, (void *)((unsigned long) id),
+ &iter.iter, stream, node_session_id.node) {
+ /* Check the stream for data. */
+ ret = data_available(stream);
+ if (ret == 0) {
+ goto data_not_available;
+ }
+ }
+
+ /* TODO: Support to ask the relayd if the streams are remote */
+
+ /*
+ * Finding _no_ node in the hash table means that the stream(s) have been
+ * removed thus data is guaranteed to be available for analysis from the
+ * trace files. This is *only* true for local consumer and not network
+ * streaming.
+ */
+
+ /* Data is available to be read by a viewer. */
+ pthread_mutex_unlock(&consumer_data.lock);
+ return 1;
+
+data_not_available:
+ /* Data is still being extracted from buffers. */
+ pthread_mutex_unlock(&consumer_data.lock);
+ return 0;
+}