+} LTTNG_PACKED;
+
+struct lttcomm_relayd_begin_data_pending {
+ uint64_t session_id;
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_end_data_pending {
+ uint64_t session_id;
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_quiescent_control {
+ uint64_t stream_id;
+} LTTNG_PACKED;
+
+/*
+ * Index data.
+ */
+struct lttcomm_relayd_index {
+ uint64_t relay_stream_id;
+ uint64_t net_seq_num;
+ uint64_t packet_size;
+ uint64_t content_size;
+ uint64_t timestamp_begin;
+ uint64_t timestamp_end;
+ uint64_t events_discarded;
+ uint64_t stream_id;
+ /* 2.8+ */
+ uint64_t stream_instance_id;
+ uint64_t packet_seq_num;
+} LTTNG_PACKED;
+
+static inline size_t lttcomm_relayd_index_len(uint32_t major, uint32_t minor)
+{
+ if (major == 1) {
+ switch (minor) {
+ case 0:
+ return offsetof(struct lttcomm_relayd_index, stream_id)
+ + member_sizeof(struct lttcomm_relayd_index,
+ stream_id);
+ case 1:
+ return offsetof(struct lttcomm_relayd_index, packet_seq_num)
+ + member_sizeof(struct lttcomm_relayd_index,
+ packet_seq_num);
+ default:
+ abort();
+ }
+ }
+ abort();
+}
+
+/*
+ * Create session in 2.4 adds additionnal parameters for live reading.
+ */
+struct lttcomm_relayd_create_session_2_4 {
+ char session_name[RELAYD_COMM_LTTNG_NAME_MAX_2_4];
+ char hostname[RELAYD_COMM_LTTNG_HOST_NAME_MAX_2_4];
+ uint32_t live_timer;
+ uint32_t snapshot;
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_create_session_2_11 {
+ uint32_t session_name_len;
+ uint32_t hostname_len;
+ /* Optional, set to 0 to indicate it is not user-specified. */
+ uint32_t base_path_len;
+ uint32_t live_timer;
+ uint8_t snapshot;
+ uint8_t session_name_contains_creation_time;
+ /* Sessiond instance UUID */
+ lttng_uuid sessiond_uuid;
+ /* Sessiond session id */
+ uint64_t session_id;
+ /* Session creation time, in seconds since UNIX Epoch. */
+ uint64_t creation_time;
+ LTTNG_OPTIONAL_COMM(uint64_t) LTTNG_PACKED current_chunk_id;
+ /* Contains the session_name, hostname, base_path. */
+ char names[];
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_create_session_reply_2_11 {
+ struct lttcomm_relayd_status_session generic;
+ /* Includes the '\0' terminator. */
+ uint32_t output_path_length;
+ char output_path[];
+} LTTNG_PACKED;
+
+/*
+ * Used to ask the relay to reset the metadata trace file (regeneration).
+ * Send the new version of the metadata (starts at 0).
+ */
+struct lttcomm_relayd_reset_metadata {
+ uint64_t stream_id;
+ uint64_t version;
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_stream_rotation_position {
+ uint64_t stream_id;
+ /*
+ * Sequence number of the first packet belonging to the new
+ * "destination" trace chunk to which the stream is rotating.
+ *
+ * Ignored for metadata streams.
+ */
+ uint64_t rotate_at_seq_num;
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_rotate_streams {
+ uint32_t stream_count;
+ /*
+ * Streams can be rotated outside of a chunk but not be parented to
+ * a new chunk.
+ */
+ LTTNG_OPTIONAL_COMM(uint64_t) new_chunk_id;
+ /* `stream_count` positions follow. */
+ struct lttcomm_relayd_stream_rotation_position rotation_positions[];
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_create_trace_chunk {
+ uint64_t chunk_id;
+ /* Seconds since EPOCH. */
+ uint64_t creation_timestamp;
+ /* Includes trailing NULL. */
+ uint32_t override_name_length;
+ char override_name[];
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_close_trace_chunk {
+ uint64_t chunk_id;
+ /* Seconds since EPOCH. */
+ uint64_t close_timestamp;
+ /* enum lttng_trace_chunk_command_type */
+ LTTNG_OPTIONAL_COMM(uint32_t) LTTNG_PACKED close_command;
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_close_trace_chunk_reply {
+ struct lttcomm_relayd_generic_reply generic;
+ /* Includes trailing NULL. */
+ uint32_t path_length;
+ char path[];
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_trace_chunk_exists {
+ uint64_t chunk_id;
+} LTTNG_PACKED;
+
+struct lttcomm_relayd_trace_chunk_exists_reply {
+ struct lttcomm_relayd_generic_reply generic;
+ uint8_t trace_chunk_exists;
+} LTTNG_PACKED;
+
+enum lttcomm_relayd_configuration_flag {
+ /* The relay daemon (2.12) is configured to allow clear operations. */
+ LTTCOMM_RELAYD_CONFIGURATION_FLAG_CLEAR_ALLOWED = (1 << 0),
+};
+
+struct lttcomm_relayd_get_configuration {
+ uint64_t query_flags;
+} LTTNG_PACKED;
+
+/*
+ * Used to return a relay daemon's configuration in reply to the
+ * RELAYD_GET_CONFIGURATION command.
+ */
+struct lttcomm_relayd_get_configuration_reply {
+ struct lttcomm_relayd_generic_reply generic;
+ /* Set of lttcomm_relayd_configuration_flag. */
+ uint64_t relayd_configuration_flags;
+ /* Optional variable-length payload. */
+ char payload[];
+} LTTNG_PACKED;