+/*
+ * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
+ *
+ * Return LTTNG_OK on success or else a LTTNG_ERR code.
+ */
+int cmd_snapshot_add_output(struct ltt_session *session,
+ struct lttng_snapshot_output *output, uint32_t *id)
+{
+ int ret;
+ struct snapshot_output *new_output;
+
+ assert(session);
+ assert(output);
+
+ DBG("Cmd snapshot add output for session %s", session->name);
+
+ /*
+ * Can't create an output if the session is not set in no-output mode.
+ */
+ if (session->output_traces) {
+ ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
+ goto error;
+ }
+
+ if (session->has_non_mmap_channel) {
+ ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
+ goto error;
+ }
+
+ /* Only one output is allowed until we have the "tee" feature. */
+ if (session->snapshot.nb_output == 1) {
+ ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
+ goto error;
+ }
+
+ new_output = snapshot_output_alloc();
+ if (!new_output) {
+ ret = LTTNG_ERR_NOMEM;
+ goto error;
+ }
+
+ ret = snapshot_output_init(session, output->max_size, output->name,
+ output->ctrl_url, output->data_url, session->consumer, new_output,
+ &session->snapshot);
+ if (ret < 0) {
+ if (ret == -ENOMEM) {
+ ret = LTTNG_ERR_NOMEM;
+ } else {
+ ret = LTTNG_ERR_INVALID;
+ }
+ goto free_error;
+ }
+
+ rcu_read_lock();
+ snapshot_add_output(&session->snapshot, new_output);
+ if (id) {
+ *id = new_output->id;
+ }
+ rcu_read_unlock();
+
+ return LTTNG_OK;
+
+free_error:
+ snapshot_output_destroy(new_output);
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
+ *
+ * Return LTTNG_OK on success or else a LTTNG_ERR code.
+ */
+int cmd_snapshot_del_output(struct ltt_session *session,
+ struct lttng_snapshot_output *output)
+{
+ int ret;
+ struct snapshot_output *sout = NULL;
+
+ assert(session);
+ assert(output);
+
+ rcu_read_lock();
+
+ /*
+ * Permission denied to create an output if the session is not
+ * set in no output mode.
+ */
+ if (session->output_traces) {
+ ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
+ goto error;
+ }
+
+ if (output->id) {
+ DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
+ session->name);
+ sout = snapshot_find_output_by_id(output->id, &session->snapshot);
+ } else if (*output->name != '\0') {
+ DBG("Cmd snapshot del output name %s for session %s", output->name,
+ session->name);
+ sout = snapshot_find_output_by_name(output->name, &session->snapshot);
+ }
+ if (!sout) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ snapshot_delete_output(&session->snapshot, sout);
+ snapshot_output_destroy(sout);
+ ret = LTTNG_OK;
+
+error:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
+ *
+ * If no output is available, outputs is untouched and 0 is returned.
+ *
+ * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
+ */
+ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
+ struct lttng_snapshot_output **outputs)
+{
+ int ret, idx = 0;
+ struct lttng_snapshot_output *list = NULL;
+ struct lttng_ht_iter iter;
+ struct snapshot_output *output;
+
+ assert(session);
+ assert(outputs);
+
+ DBG("Cmd snapshot list outputs for session %s", session->name);
+
+ /*
+ * Permission denied to create an output if the session is not
+ * set in no output mode.
+ */
+ if (session->output_traces) {
+ ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
+ goto end;
+ }
+
+ if (session->snapshot.nb_output == 0) {
+ ret = 0;
+ goto end;
+ }
+
+ list = zmalloc(session->snapshot.nb_output * sizeof(*list));
+ if (!list) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ /* Copy list from session to the new list object. */
+ rcu_read_lock();
+ cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
+ output, node.node) {
+ assert(output->consumer);
+ list[idx].id = output->id;
+ list[idx].max_size = output->max_size;
+ if (lttng_strncpy(list[idx].name, output->name,
+ sizeof(list[idx].name))) {
+ ret = -LTTNG_ERR_INVALID;
+ goto error;
+ }
+ if (output->consumer->type == CONSUMER_DST_LOCAL) {
+ if (lttng_strncpy(list[idx].ctrl_url,
+ output->consumer->dst.session_root_path,
+ sizeof(list[idx].ctrl_url))) {
+ ret = -LTTNG_ERR_INVALID;
+ goto error;
+ }
+ } else {
+ /* Control URI. */
+ ret = uri_to_str_url(&output->consumer->dst.net.control,
+ list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
+ if (ret < 0) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto error;
+ }
+
+ /* Data URI. */
+ ret = uri_to_str_url(&output->consumer->dst.net.data,
+ list[idx].data_url, sizeof(list[idx].data_url));
+ if (ret < 0) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto error;
+ }
+ }
+ idx++;
+ }
+
+ *outputs = list;
+ list = NULL;
+ ret = session->snapshot.nb_output;
+error:
+ rcu_read_unlock();
+ free(list);
+end:
+ return ret;
+}
+
+/*
+ * Check if we can regenerate the metadata for this session.
+ * Only kernel, UST per-uid and non-live sessions are supported.
+ *
+ * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
+ */
+static
+int check_regenerate_metadata_support(struct ltt_session *session)
+{
+ int ret;
+
+ assert(session);
+
+ if (session->live_timer != 0) {
+ ret = LTTNG_ERR_LIVE_SESSION;
+ goto end;
+ }
+ if (!session->active) {
+ ret = LTTNG_ERR_SESSION_NOT_STARTED;
+ goto end;
+ }
+ if (session->ust_session) {
+ switch (session->ust_session->buffer_type) {
+ case LTTNG_BUFFER_PER_UID:
+ break;
+ case LTTNG_BUFFER_PER_PID:
+ ret = LTTNG_ERR_PER_PID_SESSION;
+ goto end;
+ default:
+ assert(0);
+ ret = LTTNG_ERR_UNK;
+ goto end;
+ }
+ }
+ if (session->consumer->type == CONSUMER_DST_NET &&
+ session->consumer->relay_minor_version < 8) {
+ ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
+ goto end;
+ }
+ ret = 0;
+
+end:
+ return ret;
+}
+
+static
+int clear_metadata_file(int fd)
+{
+ int ret;
+ off_t lseek_ret;
+
+ lseek_ret = lseek(fd, 0, SEEK_SET);
+ if (lseek_ret < 0) {
+ PERROR("lseek");
+ ret = -1;
+ goto end;
+ }
+
+ ret = ftruncate(fd, 0);
+ if (ret < 0) {
+ PERROR("ftruncate");
+ goto end;
+ }
+
+end:
+ return ret;
+}
+
+static
+int ust_regenerate_metadata(struct ltt_ust_session *usess)
+{
+ int ret = 0;
+ struct buffer_reg_uid *uid_reg = NULL;
+ struct buffer_reg_session *session_reg = NULL;
+
+ rcu_read_lock();
+ cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
+ struct ust_registry_session *registry;
+ struct ust_registry_channel *chan;
+ struct lttng_ht_iter iter_chan;
+
+ session_reg = uid_reg->registry;
+ registry = session_reg->reg.ust;
+
+ pthread_mutex_lock(®istry->lock);
+ registry->metadata_len_sent = 0;
+ memset(registry->metadata, 0, registry->metadata_alloc_len);
+ registry->metadata_len = 0;
+ registry->metadata_version++;
+ if (registry->metadata_fd > 0) {
+ /* Clear the metadata file's content. */
+ ret = clear_metadata_file(registry->metadata_fd);
+ if (ret) {
+ pthread_mutex_unlock(®istry->lock);
+ goto end;
+ }
+ }
+
+ ret = ust_metadata_session_statedump(registry, NULL,
+ registry->major, registry->minor);
+ if (ret) {
+ pthread_mutex_unlock(®istry->lock);
+ ERR("Failed to generate session metadata (err = %d)",
+ ret);
+ goto end;
+ }
+ cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
+ chan, node.node) {
+ struct ust_registry_event *event;
+ struct lttng_ht_iter iter_event;
+
+ ret = ust_metadata_channel_statedump(registry, chan);
+ if (ret) {
+ pthread_mutex_unlock(®istry->lock);
+ ERR("Failed to generate channel metadata "
+ "(err = %d)", ret);
+ goto end;
+ }
+ cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
+ event, node.node) {
+ ret = ust_metadata_event_statedump(registry,
+ chan, event);
+ if (ret) {
+ pthread_mutex_unlock(®istry->lock);
+ ERR("Failed to generate event metadata "
+ "(err = %d)", ret);
+ goto end;
+ }
+ }
+ }
+ pthread_mutex_unlock(®istry->lock);
+ }
+
+end:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
+ *
+ * Ask the consumer to truncate the existing metadata file(s) and
+ * then regenerate the metadata. Live and per-pid sessions are not
+ * supported and return an error.
+ *
+ * Return 0 on success or else a LTTNG_ERR code.
+ */
+int cmd_regenerate_metadata(struct ltt_session *session)
+{
+ int ret;
+
+ assert(session);
+
+ ret = check_regenerate_metadata_support(session);
+ if (ret) {
+ goto end;
+ }
+
+ if (session->kernel_session) {
+ ret = kernctl_session_regenerate_metadata(
+ session->kernel_session->fd);
+ if (ret < 0) {
+ ERR("Failed to regenerate the kernel metadata");
+ goto end;
+ }
+ }
+
+ if (session->ust_session) {
+ ret = ust_regenerate_metadata(session->ust_session);
+ if (ret < 0) {
+ ERR("Failed to regenerate the UST metadata");
+ goto end;
+ }
+ }
+ DBG("Cmd metadata regenerate for session %s", session->name);
+ ret = LTTNG_OK;
+
+end:
+ return ret;
+}
+
+/*
+ * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
+ *
+ * Ask the tracer to regenerate a new statedump.
+ *
+ * Return 0 on success or else a LTTNG_ERR code.
+ */
+int cmd_regenerate_statedump(struct ltt_session *session)
+{
+ int ret;
+
+ assert(session);
+
+ if (!session->active) {
+ ret = LTTNG_ERR_SESSION_NOT_STARTED;
+ goto end;
+ }
+
+ if (session->kernel_session) {
+ ret = kernctl_session_regenerate_statedump(
+ session->kernel_session->fd);
+ /*
+ * Currently, the statedump in kernel can only fail if out
+ * of memory.
+ */
+ if (ret < 0) {
+ if (ret == -ENOMEM) {
+ ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
+ } else {
+ ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
+ }
+ ERR("Failed to regenerate the kernel statedump");
+ goto end;
+ }
+ }
+
+ if (session->ust_session) {
+ ret = ust_app_regenerate_statedump_all(session->ust_session);
+ /*
+ * Currently, the statedump in UST always returns 0.
+ */
+ if (ret < 0) {
+ ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
+ ERR("Failed to regenerate the UST statedump");
+ goto end;
+ }
+ }
+ DBG("Cmd regenerate statedump for session %s", session->name);
+ ret = LTTNG_OK;
+
+end:
+ return ret;
+}
+
+int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
+ struct notification_thread_handle *notification_thread)
+{
+ int ret;
+ size_t trigger_len;
+ ssize_t sock_recv_len;
+ struct lttng_trigger *trigger = NULL;
+ struct lttng_buffer_view view;
+ struct lttng_dynamic_buffer trigger_buffer;
+
+ lttng_dynamic_buffer_init(&trigger_buffer);
+ trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
+ ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
+ if (ret) {
+ ret = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
+ trigger_len);
+ if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
+ ERR("Failed to receive \"register trigger\" command payload");
+ /* TODO: should this be a new error enum ? */
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+
+ view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
+ if (lttng_trigger_create_from_buffer(&view, &trigger) !=
+ trigger_len) {
+ ERR("Invalid trigger payload received in \"register trigger\" command");
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+
+ ret = notification_thread_command_register_trigger(notification_thread,
+ trigger);
+ /* Ownership of trigger was transferred. */
+ trigger = NULL;
+end:
+ lttng_trigger_destroy(trigger);
+ lttng_dynamic_buffer_reset(&trigger_buffer);
+ return ret;
+}
+
+int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
+ struct notification_thread_handle *notification_thread)
+{
+ int ret;
+ size_t trigger_len;
+ ssize_t sock_recv_len;
+ struct lttng_trigger *trigger = NULL;
+ struct lttng_buffer_view view;
+ struct lttng_dynamic_buffer trigger_buffer;
+
+ lttng_dynamic_buffer_init(&trigger_buffer);
+ trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
+ ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
+ if (ret) {
+ ret = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
+ trigger_len);
+ if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
+ ERR("Failed to receive \"unregister trigger\" command payload");
+ /* TODO: should this be a new error enum ? */
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+
+ view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
+ if (lttng_trigger_create_from_buffer(&view, &trigger) !=
+ trigger_len) {
+ ERR("Invalid trigger payload received in \"unregister trigger\" command");
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+
+ ret = notification_thread_command_unregister_trigger(notification_thread,
+ trigger);
+end:
+ lttng_trigger_destroy(trigger);
+ lttng_dynamic_buffer_reset(&trigger_buffer);
+ return ret;
+}
+
+/*
+ * Send relayd sockets from snapshot output to consumer. Ignore request if the
+ * snapshot output is *not* set with a remote destination.
+ *
+ * Return LTTNG_OK on success or a LTTNG_ERR code.
+ */
+static enum lttng_error_code set_relayd_for_snapshot(
+ struct consumer_output *consumer,
+ const struct snapshot_output *snap_output,
+ const struct ltt_session *session)
+{
+ enum lttng_error_code status = LTTNG_OK;
+ struct lttng_ht_iter iter;
+ struct consumer_socket *socket;
+
+ assert(consumer);
+ assert(snap_output);
+ assert(session);
+
+ DBG2("Set relayd object from snapshot output");
+
+ /* Ignore if snapshot consumer output is not network. */
+ if (snap_output->consumer->type != CONSUMER_DST_NET) {
+ goto error;
+ }
+
+ /*
+ * For each consumer socket, create and send the relayd object of the
+ * snapshot output.
+ */
+ rcu_read_lock();
+ cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
+ socket, node.node) {
+ pthread_mutex_lock(socket->lock);
+ status = send_consumer_relayd_sockets(0, session->id,
+ snap_output->consumer, socket,
+ session->name, session->hostname,
+ session->live_timer);
+ pthread_mutex_unlock(socket->lock);
+ if (status != LTTNG_OK) {
+ rcu_read_unlock();
+ goto error;
+ }
+ }
+ rcu_read_unlock();
+
+error:
+ return status;
+}
+
+/*
+ * Record a kernel snapshot.
+ *
+ * Return LTTNG_OK on success or a LTTNG_ERR code.
+ */
+static enum lttng_error_code record_kernel_snapshot(
+ struct ltt_kernel_session *ksess,
+ const struct snapshot_output *output,
+ const struct ltt_session *session,
+ int wait, uint64_t nb_packets_per_stream)
+{
+ int ret;
+ enum lttng_error_code status;
+
+ assert(ksess);
+ assert(output);
+ assert(session);
+
+ /*
+ * Copy kernel session sockets so we can communicate with the right
+ * consumer for the snapshot record command.
+ */
+ ret = consumer_copy_sockets(output->consumer, ksess->consumer);
+ if (ret < 0) {
+ status = LTTNG_ERR_NOMEM;
+ goto error;
+ }
+
+ status = set_relayd_for_snapshot(ksess->consumer, output, session);
+ if (status != LTTNG_OK) {
+ goto error_snapshot;
+ }
+
+ status = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
+ if (status != LTTNG_OK) {
+ goto error_snapshot;
+ }
+
+ goto end;
+
+error_snapshot:
+ /* Clean up copied sockets so this output can use some other later on. */
+ consumer_destroy_output_sockets(output->consumer);
+error:
+end:
+ return status;
+}
+
+/*
+ * Record a UST snapshot.
+ *
+ * Returns LTTNG_OK on success or a LTTNG_ERR error code.
+ */
+static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
+ const struct snapshot_output *output,
+ const struct ltt_session *session, int wait,
+ uint64_t nb_packets_per_stream)
+{
+ int ret;
+ enum lttng_error_code status;
+
+ assert(usess);
+ assert(output);
+ assert(session);
+
+ /*
+ * Copy UST session sockets so we can communicate with the right
+ * consumer for the snapshot record command.
+ */
+ ret = consumer_copy_sockets(output->consumer, usess->consumer);
+ if (ret < 0) {
+ status = LTTNG_ERR_NOMEM;
+ goto error;
+ }
+
+ status = set_relayd_for_snapshot(usess->consumer, output, session);
+ if (status != LTTNG_OK) {
+ goto error_snapshot;
+ }
+
+ status = ust_app_snapshot_record(usess, output, wait,
+ nb_packets_per_stream);
+ if (status != LTTNG_OK) {
+ goto error_snapshot;
+ }
+
+ goto end;
+
+error_snapshot:
+ /* Clean up copied sockets so this output can use some other later on. */
+ consumer_destroy_output_sockets(output->consumer);
+error:
+end:
+ return status;
+}
+
+static
+uint64_t get_session_size_one_more_packet_per_stream(
+ const struct ltt_session *session, uint64_t cur_nr_packets)
+{
+ uint64_t tot_size = 0;
+
+ if (session->kernel_session) {
+ struct ltt_kernel_channel *chan;
+ const struct ltt_kernel_session *ksess =
+ session->kernel_session;
+
+ cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+ if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
+ /*
+ * Don't take channel into account if we
+ * already grab all its packets.
+ */
+ continue;
+ }
+ tot_size += chan->channel->attr.subbuf_size
+ * chan->stream_count;
+ }
+ }
+
+ if (session->ust_session) {
+ const struct ltt_ust_session *usess = session->ust_session;
+
+ tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
+ cur_nr_packets);
+ }
+
+ return tot_size;
+}
+
+/*
+ * Calculate the number of packets we can grab from each stream that
+ * fits within the overall snapshot max size.
+ *
+ * Returns -1 on error, 0 means infinite number of packets, else > 0 is
+ * the number of packets per stream.
+ *
+ * TODO: this approach is not perfect: we consider the worse case
+ * (packet filling the sub-buffers) as an upper bound, but we could do
+ * better if we do this calculation while we actually grab the packet
+ * content: we would know how much padding we don't actually store into
+ * the file.
+ *
+ * This algorithm is currently bounded by the number of packets per
+ * stream.
+ *
+ * Since we call this algorithm before actually grabbing the data, it's
+ * an approximation: for instance, applications could appear/disappear
+ * in between this call and actually grabbing data.
+ */
+static
+int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
+ uint64_t max_size)
+{
+ int64_t size_left;
+ uint64_t cur_nb_packets = 0;
+
+ if (!max_size) {
+ return 0; /* Infinite */
+ }
+
+ size_left = max_size;
+ for (;;) {
+ uint64_t one_more_packet_tot_size;
+
+ one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
+ session, cur_nb_packets);
+ if (!one_more_packet_tot_size) {
+ /* We are already grabbing all packets. */
+ break;
+ }
+ size_left -= one_more_packet_tot_size;
+ if (size_left < 0) {
+ break;
+ }
+ cur_nb_packets++;
+ }
+ if (!cur_nb_packets) {
+ /* Not enough room to grab one packet of each stream, error. */
+ return -1;
+ }
+ return cur_nb_packets;
+}
+
+static
+enum lttng_error_code snapshot_record(struct ltt_session *session,
+ const struct snapshot_output *snapshot_output, int wait)
+{
+ int fmt_ret;
+ int64_t nb_packets_per_stream;
+ char snapshot_chunk_name[LTTNG_NAME_MAX];
+ enum lttng_error_code ret = LTTNG_OK;
+ struct lttng_trace_chunk *snapshot_trace_chunk;
+
+ fmt_ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
+ "%s-%s-%" PRIu64,
+ snapshot_output->name,
+ snapshot_output->datetime,
+ snapshot_output->nb_snapshot);
+ if (fmt_ret < 0 || fmt_ret >= sizeof(snapshot_chunk_name)) {
+ ERR("Failed to format snapshot name");
+ ret = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
+ snapshot_output->name, session->name,
+ snapshot_chunk_name);
+ snapshot_trace_chunk = session_create_new_trace_chunk(session,
+ snapshot_output_get_base_path(snapshot_output),
+ snapshot_chunk_name);
+ if (!snapshot_trace_chunk) {
+ ret = LTTNG_ERR_CREATE_DIR_FAIL;
+ goto end;
+ }
+ assert(!session->current_trace_chunk);
+ ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
+ lttng_trace_chunk_put(snapshot_trace_chunk);
+ snapshot_trace_chunk = NULL;
+ if (ret) {
+ ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
+ goto end;
+ }
+
+ nb_packets_per_stream = get_session_nb_packets_per_stream(session,
+ snapshot_output->max_size);
+ if (nb_packets_per_stream < 0) {
+ ret = LTTNG_ERR_MAX_SIZE_INVALID;
+ goto end;
+ }
+
+ if (session->kernel_session) {
+ ret = record_kernel_snapshot(session->kernel_session,
+ snapshot_output, session,
+ wait, nb_packets_per_stream);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ }
+
+ if (session->ust_session) {
+ ret = record_ust_snapshot(session->ust_session,
+ snapshot_output, session,
+ wait, nb_packets_per_stream);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ }
+
+ if (session_close_trace_chunk(session, session->current_trace_chunk)) {
+ /*
+ * Don't goto end; make sure the chunk is closed for the session
+ * to allow future snapshots.
+ */
+ ERR("Failed to close snapshot trace chunk of session \"%s\"",
+ session->name);
+ ret = -1;
+ }
+ if (session_set_trace_chunk(session, NULL, NULL)) {
+ ERR("Failed to release the current trace chunk of session \"%s\"",
+ session->name);
+ ret = -1;
+ }
+end:
+ return ret;
+}
+
+/*
+ * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
+ *
+ * The wait parameter is ignored so this call always wait for the snapshot to
+ * complete before returning.
+ *
+ * Return LTTNG_OK on success or else a LTTNG_ERR code.
+ */
+int cmd_snapshot_record(struct ltt_session *session,
+ struct lttng_snapshot_output *output, int wait)
+{
+ enum lttng_error_code cmd_ret = LTTNG_OK;
+ int ret;
+ unsigned int use_tmp_output = 0;
+ struct snapshot_output tmp_output;
+ unsigned int snapshot_success = 0;
+ char datetime[16];
+
+ assert(session);
+ assert(output);
+
+ DBG("Cmd snapshot record for session %s", session->name);
+
+ /* Get the datetime for the snapshot output directory. */
+ ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
+ sizeof(datetime));
+ if (!ret) {
+ cmd_ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ /*
+ * Permission denied to create an output if the session is not
+ * set in no output mode.
+ */
+ if (session->output_traces) {
+ cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
+ goto error;
+ }
+
+ /* The session needs to be started at least once. */
+ if (!session->has_been_started) {
+ cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
+ goto error;
+ }
+
+ /* Use temporary output for the session. */
+ if (*output->ctrl_url != '\0') {
+ ret = snapshot_output_init(session, output->max_size,
+ output->name,
+ output->ctrl_url, output->data_url,
+ session->consumer,
+ &tmp_output, NULL);
+ if (ret < 0) {
+ if (ret == -ENOMEM) {
+ cmd_ret = LTTNG_ERR_NOMEM;
+ } else {
+ cmd_ret = LTTNG_ERR_INVALID;
+ }
+ goto error;
+ }
+ /* Use the global session count for the temporary snapshot. */
+ tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
+
+ /* Use the global datetime */
+ memcpy(tmp_output.datetime, datetime, sizeof(datetime));
+ use_tmp_output = 1;
+ }
+
+ if (use_tmp_output) {
+ cmd_ret = snapshot_record(session, &tmp_output, wait);
+ if (cmd_ret != LTTNG_OK) {
+ goto error;
+ }
+ snapshot_success = 1;
+ } else {
+ struct snapshot_output *sout;
+ struct lttng_ht_iter iter;
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
+ &iter.iter, sout, node.node) {
+ /*
+ * Make a local copy of the output and assign the
+ * possible temporary value given by the caller.
+ */
+ memcpy(&tmp_output, sout, sizeof(tmp_output));
+
+ if (output->max_size != (uint64_t) -1ULL) {
+ tmp_output.max_size = output->max_size;
+ }
+
+ tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
+ memcpy(tmp_output.datetime, datetime, sizeof(datetime));
+
+ /* Use temporary name. */
+ if (*output->name != '\0') {
+ if (lttng_strncpy(tmp_output.name, output->name,
+ sizeof(tmp_output.name))) {
+ cmd_ret = LTTNG_ERR_INVALID;
+ rcu_read_unlock();
+ goto error;
+ }
+ }
+
+ cmd_ret = snapshot_record(session, &tmp_output, wait);
+ if (cmd_ret != LTTNG_OK) {
+ rcu_read_unlock();
+ goto error;
+ }
+ snapshot_success = 1;
+ }
+ rcu_read_unlock();
+ }
+
+ if (snapshot_success) {
+ session->snapshot.nb_snapshot++;
+ } else {
+ cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
+ }
+
+error:
+ return cmd_ret;
+}
+
+/*
+ * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
+ */
+int cmd_set_session_shm_path(struct ltt_session *session,
+ const char *shm_path)
+{
+ /* Safety net */
+ assert(session);
+
+ /*
+ * Can only set shm path before session is started.
+ */
+ if (session->has_been_started) {
+ return LTTNG_ERR_SESSION_STARTED;
+ }
+
+ strncpy(session->shm_path, shm_path,
+ sizeof(session->shm_path));
+ session->shm_path[sizeof(session->shm_path) - 1] = '\0';
+
+ return 0;
+}
+
+/*
+ * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
+ *
+ * Ask the consumer to rotate the session output directory.
+ * The session lock must be held.
+ *
+ * Returns LTTNG_OK on success or else a negative LTTng error code.
+ */
+int cmd_rotate_session(struct ltt_session *session,
+ struct lttng_rotate_session_return *rotate_return)
+{
+ int ret;
+ uint64_t ongoing_rotation_chunk_id;
+ enum lttng_error_code cmd_ret = LTTNG_OK;
+ struct lttng_trace_chunk *chunk_being_archived = NULL;
+ struct lttng_trace_chunk *new_trace_chunk = NULL;
+ enum lttng_trace_chunk_status chunk_status;
+
+ assert(session);
+
+ if (!session->has_been_started) {
+ cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
+ goto end;
+ }
+
+ if (session->live_timer || !session->output_traces) {
+ cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
+ goto end;
+ }
+
+ /* Unsupported feature in lttng-relayd before 2.11. */
+ if (session->consumer->type == CONSUMER_DST_NET &&
+ (session->consumer->relay_major_version == 2 &&
+ session->consumer->relay_minor_version < 11)) {
+ cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
+ goto end;
+ }
+
+ if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
+ DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
+ session->name);
+ cmd_ret = LTTNG_ERR_ROTATION_PENDING;
+ goto end;
+ }
+
+ /*
+ * After a stop, we only allow one rotation to occur, the other ones are
+ * useless until a new start.
+ */
+ if (session->rotated_after_last_stop) {
+ DBG("Session \"%s\" was already rotated after stop, refusing rotation",
+ session->name);
+ cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
+ goto end;
+ }
+
+ session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
+
+ if (session->active) {
+ new_trace_chunk = session_create_new_trace_chunk(session,
+ NULL, NULL);
+ if (!new_trace_chunk) {
+ cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
+ goto error;
+ }
+ }
+
+ /* The current trace chunk becomes the chunk being archived. */
+ ret = session_set_trace_chunk(session, new_trace_chunk,
+ &chunk_being_archived);
+ if (ret) {
+ cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
+ goto error;
+ }
+
+ assert(chunk_being_archived);
+ chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
+ &ongoing_rotation_chunk_id);
+ assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
+
+ chunk_status = lttng_trace_chunk_set_close_command(
+ chunk_being_archived,
+ LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
+ if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
+ cmd_ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+
+ if (session->kernel_session) {
+ cmd_ret = kernel_rotate_session(session);
+ if (cmd_ret != LTTNG_OK) {
+ goto error;
+ }
+ }
+ if (session->ust_session) {
+ cmd_ret = ust_app_rotate_session(session);
+ if (cmd_ret != LTTNG_OK) {
+ goto error;
+ }
+ }
+
+ ret = session_close_trace_chunk(session, chunk_being_archived);
+ if (ret) {
+ cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
+ goto error;
+ }
+
+ ret = timer_session_rotation_pending_check_start(session,
+ DEFAULT_ROTATE_PENDING_TIMER);
+ if (ret) {
+ cmd_ret = LTTNG_ERR_UNK;
+ goto error;
+ }
+
+ if (!session->active) {
+ session->rotated_after_last_stop = true;
+ }
+
+ if (rotate_return) {
+ rotate_return->rotation_id = ongoing_rotation_chunk_id;
+ }
+
+ session->chunk_being_archived = chunk_being_archived;
+ chunk_being_archived = NULL;
+ ret = notification_thread_command_session_rotation_ongoing(
+ notification_thread_handle,
+ session->name, session->uid, session->gid,
+ ongoing_rotation_chunk_id);
+ if (ret != LTTNG_OK) {
+ ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
+ session->name);
+ cmd_ret = ret;
+ }
+
+ DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
+ session->name, ongoing_rotation_chunk_id);
+end:
+ lttng_trace_chunk_put(new_trace_chunk);
+ lttng_trace_chunk_put(chunk_being_archived);
+ ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
+ return ret;
+error:
+ if (session_reset_rotation_state(session,
+ LTTNG_ROTATION_STATE_ERROR)) {
+ ERR("Failed to reset rotation state of session \"%s\"",
+ session->name);
+ }
+ goto end;
+}
+
+/*
+ * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
+ *
+ * Check if the session has finished its rotation.
+ *
+ * Return LTTNG_OK on success or else an LTTNG_ERR code.
+ */
+int cmd_rotate_get_info(struct ltt_session *session,
+ struct lttng_rotation_get_info_return *info_return,
+ uint64_t rotation_id)
+{
+ enum lttng_error_code cmd_ret = LTTNG_OK;
+ enum lttng_rotation_state rotation_state;
+
+ DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
+ session->most_recent_chunk_id.value);
+
+ if (session->chunk_being_archived) {
+ enum lttng_trace_chunk_status chunk_status;
+ uint64_t chunk_id;
+
+ chunk_status = lttng_trace_chunk_get_id(
+ session->chunk_being_archived,
+ &chunk_id);
+ assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
+
+ rotation_state = rotation_id == chunk_id ?
+ LTTNG_ROTATION_STATE_ONGOING :
+ LTTNG_ROTATION_STATE_EXPIRED;
+ } else {
+ if (session->last_archived_chunk_id.is_set &&
+ rotation_id != session->last_archived_chunk_id.value) {
+ rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
+ } else {
+ rotation_state = session->rotation_state;
+ }
+ }
+
+ switch (rotation_state) {
+ case LTTNG_ROTATION_STATE_NO_ROTATION:
+ DBG("Reporting that no rotation has occured within the lifetime of session \"%s\"",
+ session->name);
+ goto end;
+ case LTTNG_ROTATION_STATE_EXPIRED:
+ DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
+ rotation_id, session->name);
+ break;
+ case LTTNG_ROTATION_STATE_ONGOING:
+ DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
+ rotation_id, session->name);
+ break;
+ case LTTNG_ROTATION_STATE_COMPLETED:
+ {
+ int fmt_ret;
+ char *chunk_path;
+ char *current_tracing_path_reply;
+ size_t current_tracing_path_reply_len;
+
+ DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
+ rotation_id, session->name);
+
+ switch (session_get_consumer_destination_type(session)) {
+ case CONSUMER_DST_LOCAL:
+ current_tracing_path_reply =
+ info_return->location.local.absolute_path;
+ current_tracing_path_reply_len =
+ sizeof(info_return->location.local.absolute_path);
+ info_return->location_type =
+ (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
+ break;
+ case CONSUMER_DST_NET:
+ current_tracing_path_reply =
+ info_return->location.relay.relative_path;
+ current_tracing_path_reply_len =
+ sizeof(info_return->location.relay.relative_path);
+ /* Currently the only supported relay protocol. */
+ info_return->location.relay.protocol =
+ (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
+
+ fmt_ret = lttng_strncpy(info_return->location.relay.host,
+ session_get_net_consumer_hostname(session),
+ sizeof(info_return->location.relay.host));
+ if (fmt_ret) {
+ ERR("Failed to copy host name to rotate_get_info reply");
+ info_return->status = LTTNG_ROTATION_STATUS_ERROR;
+ cmd_ret = LTTNG_ERR_SET_URL;
+ goto end;
+ }
+
+ session_get_net_consumer_ports(session,
+ &info_return->location.relay.ports.control,
+ &info_return->location.relay.ports.data);
+ info_return->location_type =
+ (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
+ break;
+ default:
+ abort();
+ }
+ fmt_ret = asprintf(&chunk_path,
+ "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
+ session_get_base_path(session),
+ session->last_archived_chunk_name);
+ if (fmt_ret == -1) {
+ PERROR("Failed to format the path of the last archived trace chunk");
+ info_return->status = LTTNG_ROTATION_STATUS_ERROR;
+ cmd_ret = LTTNG_ERR_UNK;
+ goto end;
+ }
+
+ fmt_ret = lttng_strncpy(current_tracing_path_reply,
+ chunk_path, current_tracing_path_reply_len);
+ free(chunk_path);
+ if (fmt_ret) {
+ ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
+ info_return->status = LTTNG_ROTATION_STATUS_ERROR;
+ cmd_ret = LTTNG_ERR_UNK;
+ goto end;
+ }
+
+ break;
+ }
+ case LTTNG_ROTATION_STATE_ERROR:
+ DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
+ rotation_id, session->name);
+ break;
+ default:
+ abort();
+ }
+
+ cmd_ret = LTTNG_OK;
+end:
+ info_return->status = (int32_t) rotation_state;
+ return cmd_ret;
+}
+
+/*
+ * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
+ *
+ * Configure the automatic rotation parameters.
+ * 'activate' to true means activate the rotation schedule type with 'new_value'.
+ * 'activate' to false means deactivate the rotation schedule and validate that
+ * 'new_value' has the same value as the currently active value.
+ *
+ * Return 0 on success or else a positive LTTNG_ERR code.
+ */
+int cmd_rotation_set_schedule(struct ltt_session *session,
+ bool activate, enum lttng_rotation_schedule_type schedule_type,
+ uint64_t new_value,
+ struct notification_thread_handle *notification_thread_handle)
+{
+ int ret;
+ uint64_t *parameter_value;
+
+ assert(session);
+
+ DBG("Cmd rotate set schedule session %s", session->name);
+
+ if (session->live_timer || !session->output_traces) {
+ DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
+ ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
+ goto end;
+ }
+
+ switch (schedule_type) {
+ case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
+ parameter_value = &session->rotate_size;
+ break;
+ case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
+ parameter_value = &session->rotate_timer_period;
+ if (new_value >= UINT_MAX) {
+ DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
+ new_value, UINT_MAX);
+ ret = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ break;
+ default:
+ WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
+ ret = LTTNG_ERR_INVALID;
+ goto end;
+ }
+
+ /* Improper use of the API. */
+ if (new_value == -1ULL) {
+ WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
+ ret = LTTNG_ERR_INVALID;
+ goto end;
+ }
+
+ /*
+ * As indicated in struct ltt_session's comments, a value of == 0 means
+ * this schedule rotation type is not in use.
+ *
+ * Reject the command if we were asked to activate a schedule that was
+ * already active.
+ */
+ if (activate && *parameter_value != 0) {
+ DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
+ ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
+ goto end;
+ }
+
+ /*
+ * Reject the command if we were asked to deactivate a schedule that was
+ * not active.
+ */
+ if (!activate && *parameter_value == 0) {
+ DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
+ ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
+ goto end;
+ }
+
+ /*
+ * Reject the command if we were asked to deactivate a schedule that
+ * doesn't exist.
+ */
+ if (!activate && *parameter_value != new_value) {
+ DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
+ ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
+ goto end;
+ }
+
+ *parameter_value = activate ? new_value : 0;
+
+ switch (schedule_type) {
+ case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
+ if (activate && session->active) {
+ /*
+ * Only start the timer if the session is active,
+ * otherwise it will be started when the session starts.
+ */
+ ret = timer_session_rotation_schedule_timer_start(
+ session, new_value);
+ if (ret) {
+ ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
+ ret = LTTNG_ERR_UNK;
+ goto end;
+ }
+ } else {
+ ret = timer_session_rotation_schedule_timer_stop(
+ session);
+ if (ret) {
+ ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
+ ret = LTTNG_ERR_UNK;
+ goto end;
+ }
+ }
+ break;
+ case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
+ if (activate) {
+ ret = subscribe_session_consumed_size_rotation(session,
+ new_value, notification_thread_handle);
+ if (ret) {
+ ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
+ ret = LTTNG_ERR_UNK;
+ goto end;
+ }
+ } else {
+ ret = unsubscribe_session_consumed_size_rotation(session,
+ notification_thread_handle);
+ if (ret) {
+ ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
+ ret = LTTNG_ERR_UNK;
+ goto end;
+ }
+
+ }
+ break;
+ default:
+ /* Would have been caught before. */
+ abort();
+ }
+
+ ret = LTTNG_OK;
+
+ goto end;
+
+end:
+ return ret;
+}
+
+/* Wait for a given path to be removed before continuing. */
+static enum lttng_error_code wait_on_path(void *path_data)
+{
+ const char *shm_path = path_data;
+
+ DBG("Waiting for the shm path at %s to be removed before completing session destruction",
+ shm_path);
+ while (true) {
+ int ret;
+ struct stat st;
+
+ ret = stat(shm_path, &st);
+ if (ret) {
+ if (errno != ENOENT) {
+ PERROR("stat() returned an error while checking for the existence of the shm path");
+ } else {
+ DBG("shm path no longer exists, completing the destruction of session");
+ }
+ break;
+ } else {
+ if (!S_ISDIR(st.st_mode)) {
+ ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
+ shm_path);
+ break;
+ }
+ }
+ usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
+ }
+ return LTTNG_OK;
+}
+
+/*
+ * Returns a pointer to a handler to run on completion of a command.
+ * Returns NULL if no handler has to be run for the last command executed.
+ */
+const struct cmd_completion_handler *cmd_pop_completion_handler(void)
+{
+ struct cmd_completion_handler *handler = current_completion_handler;
+
+ current_completion_handler = NULL;
+ return handler;
+}
+