+ *_stream_state = stream_state;
+ return ret;
+}
+
+static
+struct bt_field *get_struct_field_uint(struct bt_field *struct_field,
+ const char *field_name)
+{
+ struct bt_field *field = NULL;
+ struct bt_field_type *ft = NULL;
+
+ field = bt_field_structure_get_field_by_name(struct_field,
+ field_name);
+ if (!field) {
+ BT_LOGV_STR("`%s` field does not exist.");
+ goto end;
+ }
+
+ if (!bt_field_is_integer(field)) {
+ BT_LOGV("Skipping `%s` field because its type is not an integer field type: "
+ "field-addr=%p, ft-addr=%p, ft-id=%s", field_name,
+ field, ft, bt_field_type_id_string(
+ bt_field_type_get_type_id(ft)));
+ BT_PUT(field);
+ goto end;
+ }
+
+ ft = bt_field_get_type(field);
+ assert(ft);
+
+ if (bt_field_type_integer_is_signed(ft)) {
+ BT_LOGV("Skipping `%s` integer field because its type is signed: "
+ "field-addr=%p, ft-addr=%p", field_name, field, ft);
+ BT_PUT(field);
+ goto end;
+ }
+
+end:
+ bt_put(ft);
+ return field;
+}
+
+static
+uint64_t get_packet_context_events_discarded(struct bt_packet *packet)
+{
+ struct bt_field *packet_context = NULL;
+ struct bt_field *field = NULL;
+ uint64_t retval = -1ULL;
+ int ret;
+
+ packet_context = bt_packet_get_context(packet);
+ if (!packet_context) {
+ goto end;
+ }
+
+ field = get_struct_field_uint(packet_context, "events_discarded");
+ if (!field) {
+ BT_LOGV("`events_discarded` field does not exist in packet's context field: "
+ "packet-addr=%p, packet-context-field-addr=%p",
+ packet, packet_context);
+ goto end;
+ }
+
+ assert(bt_field_is_integer(field));
+ ret = bt_field_unsigned_integer_get_value(field, &retval);
+ if (ret) {
+ BT_LOGV("Cannot get raw value of packet's context field's `events_discarded` integer field: "
+ "packet-addr=%p, field-addr=%p",
+ packet, field);
+ retval = -1ULL;
+ goto end;
+ }
+
+end:
+ bt_put(packet_context);
+ bt_put(field);
+ return retval;
+}
+
+static
+uint64_t get_packet_context_packet_seq_num(struct bt_packet *packet)
+{
+ struct bt_field *packet_context = NULL;
+ struct bt_field *field = NULL;
+ uint64_t retval = -1ULL;
+ int ret;
+
+ packet_context = bt_packet_get_context(packet);
+ if (!packet_context) {
+ goto end;
+ }
+
+ field = get_struct_field_uint(packet_context, "packet_seq_num");
+ if (!field) {
+ BT_LOGV("`packet_seq_num` field does not exist in packet's context field: "
+ "packet-addr=%p, packet-context-field-addr=%p",
+ packet, packet_context);
+ goto end;
+ }
+
+ assert(bt_field_is_integer(field));
+ ret = bt_field_unsigned_integer_get_value(field, &retval);
+ if (ret) {
+ BT_LOGV("Cannot get raw value of packet's context field's `packet_seq_num` integer field: "
+ "packet-addr=%p, field-addr=%p",
+ packet, field);
+ retval = -1ULL;
+ goto end;
+ }
+
+end:
+ bt_put(packet_context);
+ bt_put(field);
+ return retval;
+}
+
+static
+int handle_discarded_packets(
+ struct bt_notification_iterator_private_connection *iterator,
+ struct bt_packet *packet,
+ struct bt_clock_value *ts_begin,
+ struct bt_clock_value *ts_end,
+ struct stream_state *stream_state)
+{
+ struct bt_notification *notif = NULL;
+ uint64_t diff;
+ uint64_t prev_count, next_count;
+ int ret = 0;
+
+ next_count = get_packet_context_packet_seq_num(packet);
+ if (next_count == -1ULL) {
+ /*
+ * Stream does not have seqnum field, skip discarded
+ * packets feature.
+ */
+ goto end;
+ }
+ prev_count = stream_state->discarded_packets_state.cur_count;
+
+ if (prev_count != -1ULL) {
+ if (next_count < prev_count) {
+ BT_LOGW("Current value of packet's context field's `packet_seq_num` field is lesser than the previous value for the same stream: "
+ "not updating the stream state's current value: "
+ "packet-addr=%p, prev-count=%" PRIu64 ", "
+ "cur-count=%" PRIu64,
+ packet, prev_count, next_count);
+ goto end;
+ }
+ if (next_count == prev_count) {
+ BT_LOGW("Current value of packet's context field's `packet_seq_num` field is equal to the previous value for the same stream: "
+ "not updating the stream state's current value: "
+ "packet-addr=%p, prev-count=%" PRIu64 ", "
+ "cur-count=%" PRIu64,
+ packet, prev_count, next_count);
+ goto end;
+ }
+
+ diff = next_count - prev_count;
+ if (diff > 1) {
+ /*
+ * Add a discarded packets notification. The packets
+ * are considered to be lost between the state's last time
+ * and the current packet's beginning time.
+ * The counter is expected to monotonically increase of
+ * 1 for each packet. Therefore, the number of missing
+ * packets is 'diff - 1'.
+ */
+ notif = bt_notification_discarded_elements_create(
+ BT_NOTIFICATION_TYPE_DISCARDED_PACKETS,
+ stream_state->stream,
+ stream_state->discarded_packets_state.cur_begin,
+ ts_begin, diff - 1);
+ if (!notif) {
+ BT_LOGE_STR("Cannot create discarded packets notification.");
+ ret = -1;
+ goto end;
+ }
+
+ add_action_push_notif(iterator, notif);
+ }
+ }
+
+ add_action_update_stream_state_discarded_elements(iterator,
+ ACTION_TYPE_UPDATE_STREAM_STATE_DISCARDED_PACKETS,
+ stream_state, ts_end, next_count);
+
+end:
+ bt_put(notif);
+ return ret;
+}
+
+static
+int handle_discarded_events(
+ struct bt_notification_iterator_private_connection *iterator,
+ struct bt_packet *packet,
+ struct bt_clock_value *ts_begin,
+ struct bt_clock_value *ts_end,
+ struct stream_state *stream_state)
+{
+ struct bt_notification *notif = NULL;
+ uint64_t diff;
+ uint64_t next_count;
+ int ret = 0;
+
+ next_count = get_packet_context_events_discarded(packet);
+ if (next_count == -1ULL) {
+ next_count = stream_state->discarded_events_state.cur_count;
+ goto update_state;
+ }
+
+ if (next_count < stream_state->discarded_events_state.cur_count) {
+ BT_LOGW("Current value of packet's context field's `events_discarded` field is lesser than the previous value for the same stream: "
+ "not updating the stream state's current value: "
+ "packet-addr=%p, prev-count=%" PRIu64 ", "
+ "cur-count=%" PRIu64,
+ packet, stream_state->discarded_events_state.cur_count,
+ next_count);
+ goto end;
+ }
+
+ diff = next_count - stream_state->discarded_events_state.cur_count;
+ if (diff > 0) {
+ /*
+ * Add a discarded events notification. The events are
+ * considered to be lost betweem the state's last time
+ * and the current packet's end time.
+ */
+ notif = bt_notification_discarded_elements_create(
+ BT_NOTIFICATION_TYPE_DISCARDED_EVENTS,
+ stream_state->stream,
+ stream_state->discarded_events_state.cur_begin,
+ ts_end, diff);
+ if (!notif) {
+ BT_LOGE_STR("Cannot create discarded events notification.");
+ ret = -1;
+ goto end;
+ }
+
+ add_action_push_notif(iterator, notif);
+ }
+
+update_state:
+ add_action_update_stream_state_discarded_elements(iterator,
+ ACTION_TYPE_UPDATE_STREAM_STATE_DISCARDED_EVENTS,
+ stream_state, ts_end, next_count);
+
+end:
+ bt_put(notif);