+static enum relay_connection_status relay_process_control_receive_header(
+ struct relay_connection *conn)
+{
+ int ret = 0;
+ enum relay_connection_status status = RELAY_CONNECTION_STATUS_OK;
+ struct lttcomm_relayd_hdr header;
+ struct lttng_dynamic_buffer *reception_buffer =
+ &conn->protocol.ctrl.reception_buffer;
+ struct ctrl_connection_state_receive_header *state =
+ &conn->protocol.ctrl.state.receive_header;
+
+ assert(state->left_to_receive != 0);
+
+ ret = conn->sock->ops->recvmsg(conn->sock,
+ reception_buffer->data + state->received,
+ state->left_to_receive, MSG_DONTWAIT);
+ if (ret < 0) {
+ if (errno != EAGAIN && errno != EWOULDBLOCK) {
+ PERROR("Unable to receive control command header on sock %d",
+ conn->sock->fd);
+ status = RELAY_CONNECTION_STATUS_ERROR;
+ }
+ goto end;
+ } else if (ret == 0) {
+ DBG("Socket %d performed an orderly shutdown (received EOF)", conn->sock->fd);
+ status = RELAY_CONNECTION_STATUS_CLOSED;
+ goto end;
+ }
+
+ assert(ret > 0);
+ assert(ret <= state->left_to_receive);
+
+ state->left_to_receive -= ret;
+ state->received += ret;
+
+ if (state->left_to_receive > 0) {
+ /*
+ * Can't transition to the protocol's next state, wait to
+ * receive the rest of the header.
+ */
+ DBG3("Partial reception of control connection protocol header (received %" PRIu64 " bytes, %" PRIu64 " bytes left to receive, fd = %i)",
+ state->received, state->left_to_receive,
+ conn->sock->fd);
+ goto end;
+ }
+
+ /* Transition to next state: receiving the command's payload. */
+ conn->protocol.ctrl.state_id =
+ CTRL_CONNECTION_STATE_RECEIVE_PAYLOAD;
+ memcpy(&header, reception_buffer->data, sizeof(header));
+ header.circuit_id = be64toh(header.circuit_id);
+ header.data_size = be64toh(header.data_size);
+ header.cmd = be32toh(header.cmd);
+ header.cmd_version = be32toh(header.cmd_version);
+ memcpy(&conn->protocol.ctrl.state.receive_payload.header,
+ &header, sizeof(header));
+
+ DBG("Done receiving control command header: fd = %i, cmd = %" PRIu32 ", cmd_version = %" PRIu32 ", payload size = %" PRIu64 " bytes",
+ conn->sock->fd, header.cmd, header.cmd_version,
+ header.data_size);
+
+ if (header.data_size > DEFAULT_NETWORK_RELAYD_CTRL_MAX_PAYLOAD_SIZE) {
+ ERR("Command header indicates a payload (%" PRIu64 " bytes) that exceeds the maximal payload size allowed on a control connection.",
+ header.data_size);
+ status = RELAY_CONNECTION_STATUS_ERROR;
+ goto end;
+ }
+
+ conn->protocol.ctrl.state.receive_payload.left_to_receive =
+ header.data_size;
+ conn->protocol.ctrl.state.receive_payload.received = 0;
+ ret = lttng_dynamic_buffer_set_size(reception_buffer,
+ header.data_size);
+ if (ret) {
+ status = RELAY_CONNECTION_STATUS_ERROR;
+ goto end;
+ }
+
+ if (header.data_size == 0) {
+ /*
+ * Manually invoke the next state as the poll loop
+ * will not wake-up to allow us to proceed further.
+ */
+ status = relay_process_control_receive_payload(conn);
+ }
+end:
+ return status;
+}
+
+/*
+ * Process the commands received on the control socket
+ */
+static enum relay_connection_status relay_process_control(
+ struct relay_connection *conn)
+{
+ enum relay_connection_status status;
+
+ switch (conn->protocol.ctrl.state_id) {
+ case CTRL_CONNECTION_STATE_RECEIVE_HEADER:
+ status = relay_process_control_receive_header(conn);
+ break;
+ case CTRL_CONNECTION_STATE_RECEIVE_PAYLOAD:
+ status = relay_process_control_receive_payload(conn);
+ break;
+ default:
+ ERR("Unknown control connection protocol state encountered.");
+ abort();
+ }
+
+ return status;
+}
+
+/*
+ * Handle index for a data stream.
+ *
+ * Called with the stream lock held.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int handle_index_data(struct relay_stream *stream, uint64_t net_seq_num,
+ bool rotate_index)
+{
+ int ret = 0;
+ uint64_t data_offset;
+ struct relay_index *index;
+
+ /* Get data offset because we are about to update the index. */
+ data_offset = htobe64(stream->tracefile_size_current);
+
+ DBG("handle_index_data: stream %" PRIu64 " net_seq_num %" PRIu64 " data offset %" PRIu64,
+ stream->stream_handle, net_seq_num, stream->tracefile_size_current);
+
+ /*
+ * Lookup for an existing index for that stream id/sequence
+ * number. If it exists, the control thread has already received the
+ * data for it, thus we need to write it to disk.
+ */
+ index = relay_index_get_by_id_or_create(stream, net_seq_num);
+ if (!index) {
+ ret = -1;
+ goto end;
+ }
+
+ if (rotate_index || !stream->index_file) {
+ uint32_t major, minor;
+
+ /* Put ref on previous index_file. */
+ if (stream->index_file) {
+ lttng_index_file_put(stream->index_file);
+ stream->index_file = NULL;
+ }
+ major = stream->trace->session->major;
+ minor = stream->trace->session->minor;
+ stream->index_file = lttng_index_file_create(stream->path_name,
+ stream->channel_name,
+ -1, -1, stream->tracefile_size,
+ tracefile_array_get_file_index_head(stream->tfa),
+ lttng_to_index_major(major, minor),
+ lttng_to_index_minor(major, minor));
+ if (!stream->index_file) {
+ ret = -1;
+ /* Put self-ref for this index due to error. */
+ relay_index_put(index);
+ index = NULL;
+ goto end;
+ }
+ }
+
+ if (relay_index_set_file(index, stream->index_file, data_offset)) {
+ ret = -1;
+ /* Put self-ref for this index due to error. */
+ relay_index_put(index);
+ index = NULL;
+ goto end;
+ }
+
+ ret = relay_index_try_flush(index);
+ if (ret == 0) {
+ tracefile_array_commit_seq(stream->tfa);
+ stream->index_received_seqcount++;
+ } else if (ret > 0) {
+ /* No flush. */
+ ret = 0;
+ } else {
+ /* Put self-ref for this index due to error. */
+ relay_index_put(index);
+ index = NULL;
+ ret = -1;
+ }
+end:
+ return ret;
+}
+
+static enum relay_connection_status relay_process_data_receive_header(
+ struct relay_connection *conn)