+ /*
+ * Empty filter string will always be rejected by the parser
+ * anyway, so treat this corner-case early to eliminate
+ * lttng_fmemopen error for 0-byte allocation.
+ */
+ if (filter_expression && filter_expression[0] == '\0') {
+ ret = -LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+
+ /* If no channel name, send empty string. */
+ if (channel_name == NULL) {
+ lttng_ctl_copy_string(lsm.u.enable.channel_name, "",
+ sizeof(lsm.u.enable.channel_name));
+ } else {
+ lttng_ctl_copy_string(lsm.u.enable.channel_name, channel_name,
+ sizeof(lsm.u.enable.channel_name));
+ }
+
+ lsm.cmd_type = LTTNG_ENABLE_EVENT;
+ if (ev->name[0] == '\0') {
+ /* Enable all events */
+ lttng_ctl_copy_string(ev->name, "*", sizeof(ev->name));
+ }
+
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+ /* FIXME: copying non-packed struct to packed struct. */
+ memcpy(&lsm.u.enable.event, ev, sizeof(lsm.u.enable.event));
+
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+ lsm.u.enable.exclusion_count = exclusion_count;
+ lsm.u.enable.bytecode_len = 0;
+
+ /*
+ * We have either a filter or some exclusions, so we need to set up
+ * a variable-length memory block from where to send the data.
+ */
+ lttng_dynamic_buffer_init(&send_buffer);
+
+ /* Parse filter expression. */
+ if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
+ || handle->domain.type == LTTNG_DOMAIN_LOG4J
+ || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
+ if (handle->domain.type == LTTNG_DOMAIN_JUL ||
+ handle->domain.type == LTTNG_DOMAIN_LOG4J ||
+ handle->domain.type == LTTNG_DOMAIN_PYTHON) {
+ char *agent_filter;
+
+ /* Setup JUL filter if needed. */
+ agent_filter = set_agent_filter(filter_expression, ev);
+ if (!agent_filter) {
+ if (!filter_expression) {
+ /*
+ * No JUL and no filter, just skip
+ * everything below.
+ */
+ goto ask_sessiond;
+ }
+ } else {
+ /*
+ * With an agent filter, the original filter has
+ * been added to it thus replace the filter
+ * expression.
+ */
+ filter_expression = agent_filter;
+ free_filter_expression = 1;
+ }
+ }
+
+ ret = generate_filter(filter_expression, &lsm, &ctx);
+ if (ret) {
+ goto filter_error;
+ }
+ }
+
+ ret = lttng_dynamic_buffer_set_capacity(&send_buffer,
+ lsm.u.enable.bytecode_len
+ + lsm.u.enable.expression_len
+ + LTTNG_SYMBOL_NAME_LEN * exclusion_count);
+ if (ret) {
+ ret = -LTTNG_ERR_EXCLUSION_NOMEM;
+ goto mem_error;
+ }
+
+ /* Put exclusion names first in the data. */
+ for (i = 0; i < exclusion_count; i++) {
+ size_t exclusion_len;
+
+ exclusion_len = lttng_strnlen(*(exclusion_list + i),
+ LTTNG_SYMBOL_NAME_LEN);
+ if (exclusion_len == LTTNG_SYMBOL_NAME_LEN) {
+ /* Exclusion is not NULL-terminated. */
+ ret = -LTTNG_ERR_INVALID;
+ goto mem_error;
+ }
+
+ ret = lttng_dynamic_buffer_append(&send_buffer,
+ *(exclusion_list + i),
+ LTTNG_SYMBOL_NAME_LEN);
+ if (ret) {
+ goto mem_error;
+ }
+ }
+
+ /* Add filter expression next. */
+ if (filter_expression) {
+ ret = lttng_dynamic_buffer_append(&send_buffer,
+ filter_expression, lsm.u.enable.expression_len);
+ if (ret) {
+ goto mem_error;
+ }
+ }
+ /* Add filter bytecode next. */
+ if (ctx && lsm.u.enable.bytecode_len != 0) {
+ ret = lttng_dynamic_buffer_append(&send_buffer,
+ &ctx->bytecode->b, lsm.u.enable.bytecode_len);
+ if (ret) {
+ goto mem_error;
+ }
+ }
+ if (ev->extended.ptr) {
+ struct lttng_event_extended *ev_ext =
+ (struct lttng_event_extended *) ev->extended.ptr;
+
+ if (ev_ext->probe_location) {
+ /*
+ * lttng_userspace_probe_location_serialize returns the
+ * number of bytes that was appended to the buffer.
+ */
+ ret = lttng_userspace_probe_location_serialize(
+ ev_ext->probe_location, &send_buffer,
+ &fd_to_send);
+ if (ret < 0) {
+ goto mem_error;
+ }
+
+ send_fd = fd_to_send >= 0;
+ /*
+ * Set the size of the userspace probe location element
+ * of the buffer so that the receiving side knows where
+ * to split it.
+ */
+ lsm.u.enable.userspace_probe_location_len = ret;
+ }
+ }
+
+ ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm,
+ send_fd ? &fd_to_send : NULL,
+ send_fd ? 1 : 0,
+ send_buffer.size ? send_buffer.data : NULL,
+ send_buffer.size, NULL, NULL, 0);
+
+mem_error:
+ if (filter_expression && ctx) {
+ filter_bytecode_free(ctx);
+ filter_ir_free(ctx);
+ filter_parser_ctx_free(ctx);
+ }
+filter_error:
+ if (free_filter_expression) {
+ /*
+ * The filter expression has been replaced and must be freed as
+ * it is not the original filter expression received as a
+ * parameter.
+ */
+ free(filter_expression);
+ }
+error:
+ /*
+ * Return directly to the caller and don't ask the sessiond since
+ * something went wrong in the parsing of data above.
+ */
+ lttng_dynamic_buffer_reset(&send_buffer);
+ return ret;
+
+ask_sessiond:
+ ret = lttng_ctl_ask_sessiond(&lsm, NULL);
+ return ret;
+}
+
+int lttng_disable_event_ext(struct lttng_handle *handle,
+ struct lttng_event *ev, const char *channel_name,
+ const char *original_filter_expression)
+{
+ struct lttcomm_session_msg lsm;
+ char *varlen_data;
+ int ret = 0;
+ unsigned int free_filter_expression = 0;
+ struct filter_parser_ctx *ctx = NULL;
+ /*
+ * Cast as non-const since we may replace the filter expression
+ * by a dynamically allocated string. Otherwise, the original
+ * string is not modified.
+ */
+ char *filter_expression = (char *) original_filter_expression;
+
+ if (handle == NULL || ev == NULL) {
+ ret = -LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ /*
+ * Empty filter string will always be rejected by the parser
+ * anyway, so treat this corner-case early to eliminate
+ * lttng_fmemopen error for 0-byte allocation.
+ */
+ if (filter_expression && filter_expression[0] == '\0') {
+ ret = -LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+
+ /* If no channel name, send empty string. */
+ if (channel_name == NULL) {
+ lttng_ctl_copy_string(lsm.u.disable.channel_name, "",
+ sizeof(lsm.u.disable.channel_name));
+ } else {
+ lttng_ctl_copy_string(lsm.u.disable.channel_name, channel_name,
+ sizeof(lsm.u.disable.channel_name));
+ }
+
+ lsm.cmd_type = LTTNG_DISABLE_EVENT;
+
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+ /* FIXME: copying non-packed struct to packed struct. */
+ memcpy(&lsm.u.disable.event, ev, sizeof(lsm.u.disable.event));
+
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+ lsm.u.disable.bytecode_len = 0;
+
+ /*
+ * For the JUL domain, a filter is enforced except for the
+ * disable all event. This is done to avoid having the event in
+ * all sessions thus filtering by logger name.
+ */
+ if (filter_expression == NULL &&
+ (handle->domain.type != LTTNG_DOMAIN_JUL &&
+ handle->domain.type != LTTNG_DOMAIN_LOG4J &&
+ handle->domain.type != LTTNG_DOMAIN_PYTHON)) {
+ goto ask_sessiond;
+ }
+
+ /*
+ * We have a filter, so we need to set up a variable-length
+ * memory block from where to send the data.
+ */
+
+ /* Parse filter expression */
+ if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
+ || handle->domain.type == LTTNG_DOMAIN_LOG4J
+ || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
+ if (handle->domain.type == LTTNG_DOMAIN_JUL ||
+ handle->domain.type == LTTNG_DOMAIN_LOG4J ||
+ handle->domain.type == LTTNG_DOMAIN_PYTHON) {
+ char *agent_filter;
+
+ /* Setup JUL filter if needed. */
+ agent_filter = set_agent_filter(filter_expression, ev);
+ if (!agent_filter) {
+ if (!filter_expression) {
+ /*
+ * No JUL and no filter, just skip
+ * everything below.
+ */
+ goto ask_sessiond;
+ }
+ } else {
+ /*
+ * With a JUL filter, the original filter has
+ * been added to it thus replace the filter
+ * expression.
+ */
+ filter_expression = agent_filter;
+ free_filter_expression = 1;
+ }
+ }
+
+ ret = generate_filter(filter_expression, &lsm, &ctx);
+ if (ret) {
+ goto filter_error;
+ }
+ }
+
+ varlen_data = zmalloc(lsm.u.disable.bytecode_len
+ + lsm.u.disable.expression_len);
+ if (!varlen_data) {
+ ret = -LTTNG_ERR_EXCLUSION_NOMEM;
+ goto mem_error;
+ }
+
+ /* Add filter expression. */
+ if (lsm.u.disable.expression_len != 0) {
+ memcpy(varlen_data,
+ filter_expression,
+ lsm.u.disable.expression_len);
+ }
+ /* Add filter bytecode next. */
+ if (ctx && lsm.u.disable.bytecode_len != 0) {
+ memcpy(varlen_data
+ + lsm.u.disable.expression_len,
+ &ctx->bytecode->b,
+ lsm.u.disable.bytecode_len);
+ }
+
+ ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, varlen_data,
+ lsm.u.disable.bytecode_len + lsm.u.disable.expression_len, NULL);
+ free(varlen_data);
+
+mem_error:
+ if (filter_expression && ctx) {
+ filter_bytecode_free(ctx);
+ filter_ir_free(ctx);
+ filter_parser_ctx_free(ctx);
+ }
+filter_error:
+ if (free_filter_expression) {
+ /*
+ * The filter expression has been replaced and must be freed as
+ * it is not the original filter expression received as a
+ * parameter.
+ */
+ free(filter_expression);
+ }
+error:
+ /*
+ * Return directly to the caller and don't ask the sessiond since
+ * something went wrong in the parsing of data above.
+ */
+ return ret;
+
+ask_sessiond:
+ ret = lttng_ctl_ask_sessiond(&lsm, NULL);
+ return ret;
+}
+
+/*
+ * Disable event(s) of a channel and domain.
+ * If no event name is specified, all events are disabled.
+ * If no channel name is specified, the default 'channel0' is used.
+ * Returns size of returned session payload data or a negative error code.
+ */
+int lttng_disable_event(struct lttng_handle *handle, const char *name,
+ const char *channel_name)
+{
+ struct lttng_event ev;
+
+ memset(&ev, 0, sizeof(ev));
+ ev.loglevel = -1;
+ ev.type = LTTNG_EVENT_ALL;
+ lttng_ctl_copy_string(ev.name, name, sizeof(ev.name));
+ return lttng_disable_event_ext(handle, &ev, channel_name, NULL);
+}
+
+struct lttng_channel *lttng_channel_create(struct lttng_domain *domain)
+{
+ struct lttng_channel *channel = NULL;
+ struct lttng_channel_extended *extended = NULL;
+
+ if (!domain) {
+ goto error;
+ }
+
+ /* Validate domain. */
+ switch (domain->type) {
+ case LTTNG_DOMAIN_UST:
+ switch (domain->buf_type) {
+ case LTTNG_BUFFER_PER_UID:
+ case LTTNG_BUFFER_PER_PID:
+ break;
+ default:
+ goto error;
+ }
+ break;
+ case LTTNG_DOMAIN_KERNEL:
+ if (domain->buf_type != LTTNG_BUFFER_GLOBAL) {
+ goto error;
+ }
+ break;
+ default:
+ goto error;
+ }
+
+ channel = zmalloc(sizeof(*channel));
+ if (!channel) {
+ goto error;
+ }
+
+ extended = zmalloc(sizeof(*extended));
+ if (!extended) {
+ goto error;
+ }
+
+ channel->attr.extended.ptr = extended;
+
+ lttng_channel_set_default_attr(domain, &channel->attr);
+ return channel;
+error:
+ free(channel);
+ free(extended);
+ return NULL;
+}
+
+void lttng_channel_destroy(struct lttng_channel *channel)
+{
+ if (!channel) {
+ return;
+ }
+
+ if (channel->attr.extended.ptr) {
+ free(channel->attr.extended.ptr);
+ }
+ free(channel);
+}
+
+/*
+ * Enable channel per domain
+ * Returns size of returned session payload data or a negative error code.
+ */
+int lttng_enable_channel(struct lttng_handle *handle,
+ struct lttng_channel *in_chan)
+{
+ struct lttcomm_session_msg lsm;
+ size_t total_buffer_size_needed_per_cpu = 0;
+
+ /* NULL arguments are forbidden. No default values. */
+ if (handle == NULL || in_chan == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ memcpy(&lsm.u.channel.chan, in_chan, sizeof(lsm.u.channel.chan));
+ lsm.u.channel.chan.attr.extended.ptr = NULL;
+
+ if (!in_chan->attr.extended.ptr) {
+ struct lttng_channel *channel;
+ struct lttng_channel_extended *extended;
+
+ channel = lttng_channel_create(&handle->domain);
+ if (!channel) {
+ return -LTTNG_ERR_NOMEM;
+ }
+
+ /*
+ * Create a new channel in order to use default extended
+ * attribute values.
+ */
+ extended = (struct lttng_channel_extended *)
+ channel->attr.extended.ptr;
+ memcpy(&lsm.u.channel.extended, extended, sizeof(*extended));
+ lttng_channel_destroy(channel);
+ } else {
+ struct lttng_channel_extended *extended;
+
+ extended = (struct lttng_channel_extended *)
+ in_chan->attr.extended.ptr;
+ memcpy(&lsm.u.channel.extended, extended, sizeof(*extended));
+ }
+
+ /*
+ * Verify that the amount of memory required to create the requested
+ * buffer is available on the system at the moment.
+ */
+ total_buffer_size_needed_per_cpu = lsm.u.channel.chan.attr.num_subbuf *
+ lsm.u.channel.chan.attr.subbuf_size;
+ if (!check_enough_available_memory(total_buffer_size_needed_per_cpu)) {
+ return -LTTNG_ERR_NOMEM;
+ }
+
+ lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+
+ return lttng_ctl_ask_sessiond(&lsm, NULL);
+}
+
+/*
+ * All tracing will be stopped for registered events of the channel.
+ * Returns size of returned session payload data or a negative error code.
+ */
+int lttng_disable_channel(struct lttng_handle *handle, const char *name)
+{
+ struct lttcomm_session_msg lsm;
+
+ /* Safety check. Both are mandatory. */
+ if (handle == NULL || name == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+
+ lsm.cmd_type = LTTNG_DISABLE_CHANNEL;
+
+ lttng_ctl_copy_string(lsm.u.disable.channel_name, name,
+ sizeof(lsm.u.disable.channel_name));
+
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+
+ return lttng_ctl_ask_sessiond(&lsm, NULL);
+}
+
+/*
+ * Add PID to session tracker.
+ * Return 0 on success else a negative LTTng error code.
+ */
+int lttng_track_pid(struct lttng_handle *handle, int pid)
+{
+ struct lttcomm_session_msg lsm;
+
+ /* NULL arguments are forbidden. No default values. */
+ if (handle == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+
+ lsm.cmd_type = LTTNG_TRACK_PID;
+ lsm.u.pid_tracker.pid = pid;
+
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+
+ return lttng_ctl_ask_sessiond(&lsm, NULL);
+}
+
+/*
+ * Remove PID from session tracker.
+ * Return 0 on success else a negative LTTng error code.
+ */
+int lttng_untrack_pid(struct lttng_handle *handle, int pid)
+{
+ struct lttcomm_session_msg lsm;
+
+ /* NULL arguments are forbidden. No default values. */
+ if (handle == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+
+ lsm.cmd_type = LTTNG_UNTRACK_PID;
+ lsm.u.pid_tracker.pid = pid;
+
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+
+ return lttng_ctl_ask_sessiond(&lsm, NULL);
+}
+
+/*
+ * Lists all available tracepoints of domain.
+ * Sets the contents of the events array.
+ * Returns the number of lttng_event entries in events;
+ * on error, returns a negative value.
+ */
+int lttng_list_tracepoints(struct lttng_handle *handle,
+ struct lttng_event **events)
+{
+ int ret;
+ struct lttcomm_session_msg lsm;
+
+ if (handle == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_LIST_TRACEPOINTS;
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return ret / sizeof(struct lttng_event);
+}
+
+/*
+ * Lists all available tracepoint fields of domain.
+ * Sets the contents of the event field array.
+ * Returns the number of lttng_event_field entries in events;
+ * on error, returns a negative value.
+ */
+int lttng_list_tracepoint_fields(struct lttng_handle *handle,
+ struct lttng_event_field **fields)
+{
+ int ret;
+ struct lttcomm_session_msg lsm;
+
+ if (handle == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_LIST_TRACEPOINT_FIELDS;
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ ret = lttng_ctl_ask_sessiond(&lsm, (void **) fields);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return ret / sizeof(struct lttng_event_field);
+}
+
+/*
+ * Lists all available kernel system calls. Allocates and sets the contents of
+ * the events array.
+ *
+ * Returns the number of lttng_event entries in events; on error, returns a
+ * negative value.
+ */
+int lttng_list_syscalls(struct lttng_event **events)
+{
+ int ret;
+ struct lttcomm_session_msg lsm;
+
+ if (!events) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_LIST_SYSCALLS;
+ /* Force kernel domain for system calls. */
+ lsm.domain.type = LTTNG_DOMAIN_KERNEL;
+
+ ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return ret / sizeof(struct lttng_event);
+}
+
+/*
+ * Returns a human readable string describing
+ * the error code (a negative value).
+ */
+const char *lttng_strerror(int code)
+{
+ return error_get_str(code);
+}
+
+/*
+ * Create a brand new session using name and url for destination.
+ *
+ * Returns LTTNG_OK on success or a negative error code.
+ */
+int lttng_create_session(const char *name, const char *url)
+{
+ int ret;
+ ssize_t size;
+ struct lttcomm_session_msg lsm;
+ struct lttng_uri *uris = NULL;
+
+ if (name == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+
+ lsm.cmd_type = LTTNG_CREATE_SESSION;
+ lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
+
+ /* There should never be a data URL */
+ size = uri_parse_str_urls(url, NULL, &uris);
+ if (size < 0) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ lsm.u.uri.size = size;
+
+ ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, uris,
+ sizeof(struct lttng_uri) * size, NULL);
+
+ free(uris);
+ return ret;
+}
+
+/*
+ * Destroy session using name.
+ * Returns size of returned session payload data or a negative error code.
+ */
+static
+int _lttng_destroy_session(const char *session_name)
+{
+ struct lttcomm_session_msg lsm;
+
+ if (session_name == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_DESTROY_SESSION;
+
+ lttng_ctl_copy_string(lsm.session.name, session_name,
+ sizeof(lsm.session.name));
+
+ return lttng_ctl_ask_sessiond(&lsm, NULL);
+}
+
+/*
+ * Stop the session and wait for the data before destroying it
+ */
+int lttng_destroy_session(const char *session_name)
+{
+ int ret;
+
+ /*
+ * Stop the tracing and wait for the data.
+ */
+ ret = _lttng_stop_tracing(session_name, 1);
+ if (ret && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
+ goto end;
+ }
+
+ ret = _lttng_destroy_session(session_name);
+end:
+ return ret;
+}
+
+/*
+ * Destroy the session without waiting for the data.
+ */
+int lttng_destroy_session_no_wait(const char *session_name)
+{
+ int ret;
+
+ /*
+ * Stop the tracing without waiting for the data.
+ * The session might already have been stopped, so just
+ * skip this error.
+ */
+ ret = _lttng_stop_tracing(session_name, 0);
+ if (ret && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
+ goto end;
+ }
+
+ ret = _lttng_destroy_session(session_name);
+end:
+ return ret;
+}
+
+/*
+ * Ask the session daemon for all available sessions.
+ * Sets the contents of the sessions array.
+ * Returns the number of lttng_session entries in sessions;
+ * on error, returns a negative value.
+ */
+int lttng_list_sessions(struct lttng_session **sessions)
+{
+ int ret;
+ struct lttcomm_session_msg lsm;
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_LIST_SESSIONS;
+ ret = lttng_ctl_ask_sessiond(&lsm, (void**) sessions);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return ret / sizeof(struct lttng_session);
+}
+
+int lttng_set_session_shm_path(const char *session_name,
+ const char *shm_path)
+{
+ struct lttcomm_session_msg lsm;
+
+ if (session_name == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_SET_SESSION_SHM_PATH;
+
+ lttng_ctl_copy_string(lsm.session.name, session_name,
+ sizeof(lsm.session.name));
+ lttng_ctl_copy_string(lsm.u.set_shm_path.shm_path, shm_path,
+ sizeof(lsm.u.set_shm_path.shm_path));
+
+ return lttng_ctl_ask_sessiond(&lsm, NULL);
+}
+
+/*
+ * Ask the session daemon for all available domains of a session.
+ * Sets the contents of the domains array.
+ * Returns the number of lttng_domain entries in domains;
+ * on error, returns a negative value.
+ */
+int lttng_list_domains(const char *session_name,
+ struct lttng_domain **domains)
+{
+ int ret;
+ struct lttcomm_session_msg lsm;
+
+ if (session_name == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_LIST_DOMAINS;
+
+ lttng_ctl_copy_string(lsm.session.name, session_name,
+ sizeof(lsm.session.name));
+
+ ret = lttng_ctl_ask_sessiond(&lsm, (void**) domains);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return ret / sizeof(struct lttng_domain);
+}
+
+/*
+ * Ask the session daemon for all available channels of a session.
+ * Sets the contents of the channels array.
+ * Returns the number of lttng_channel entries in channels;
+ * on error, returns a negative value.
+ */
+int lttng_list_channels(struct lttng_handle *handle,
+ struct lttng_channel **channels)
+{
+ int ret;
+ size_t channel_count, i;
+ const size_t channel_size = sizeof(struct lttng_channel) +
+ sizeof(struct lttng_channel_extended);
+ struct lttcomm_session_msg lsm;
+ void *extended_at;
+
+ if (handle == NULL) {
+ ret = -LTTNG_ERR_INVALID;
+ goto end;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_LIST_CHANNELS;
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ ret = lttng_ctl_ask_sessiond(&lsm, (void**) channels);
+ if (ret < 0) {
+ goto end;
+ }
+
+ if (ret % channel_size) {
+ ret = -LTTNG_ERR_UNK;
+ free(*channels);
+ *channels = NULL;
+ goto end;
+ }
+ channel_count = (size_t) ret / channel_size;
+
+ /* Set extended info pointers */
+ extended_at = ((void *) *channels) +
+ channel_count * sizeof(struct lttng_channel);
+ for (i = 0; i < channel_count; i++) {
+ struct lttng_channel *chan = &(*channels)[i];
+
+ chan->attr.extended.ptr = extended_at;
+ extended_at += sizeof(struct lttng_channel_extended);
+ }
+
+ ret = (int) channel_count;
+end:
+ return ret;
+}
+
+/*
+ * Ask the session daemon for all available events of a session channel.
+ * Sets the contents of the events array.
+ * Returns the number of lttng_event entries in events;
+ * on error, returns a negative value.
+ */
+int lttng_list_events(struct lttng_handle *handle,
+ const char *channel_name, struct lttng_event **events)
+{
+ int ret;
+ struct lttcomm_session_msg lsm;
+ struct lttcomm_event_command_header *cmd_header = NULL;
+ size_t cmd_header_len;
+ uint32_t nb_events, i;
+ void *comm_ext_at;
+ char *reception_buffer = NULL;
+ struct lttng_dynamic_buffer listing;
+ size_t storage_req;
+
+ /* Safety check. An handle and channel name are mandatory */
+ if (handle == NULL || channel_name == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+ lsm.cmd_type = LTTNG_LIST_EVENTS;
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+ lttng_ctl_copy_string(lsm.u.list.channel_name, channel_name,
+ sizeof(lsm.u.list.channel_name));
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm, NULL, 0, NULL, 0,
+ (void **) &reception_buffer, (void **) &cmd_header,
+ &cmd_header_len);
+ if (ret < 0) {
+ goto end;
+ }
+
+ if (!cmd_header) {
+ ret = -LTTNG_ERR_UNK;
+ goto end;
+ }
+
+ /* Set number of events and free command header */
+ nb_events = cmd_header->nb_events;
+ if (nb_events > INT_MAX) {
+ ret = -EOVERFLOW;
+ goto end;
+ }
+ free(cmd_header);
+ cmd_header = NULL;
+
+ /*
+ * The buffer that is returned must contain a "flat" version of
+ * the events that are returned. In other words, all pointers
+ * within an lttng_event must point to a location within the returned
+ * buffer so that the user may free everything by simply calling free()
+ * on the returned buffer. This is needed in order to maintain API
+ * compatibility.
+ *
+ * A first pass is performed to compute the size of the buffer that
+ * must be allocated. A second pass is then performed to setup
+ * the returned events so that their members always point within the
+ * buffer.
+ *
+ * The layout of the returned buffer is as follows:
+ * - struct lttng_event[nb_events],
+ * - nb_events times the following:
+ * - struct lttng_event_extended,
+ * - flattened version of userspace_probe_location
+ * - filter_expression
+ * - exclusions
+ * - padding to align to 64-bits
+ */
+ comm_ext_at = reception_buffer +
+ (nb_events * sizeof(struct lttng_event));
+ storage_req = nb_events * sizeof(struct lttng_event);
+
+ for (i = 0; i < nb_events; i++) {
+ struct lttcomm_event_extended_header *ext_comm =
+ (struct lttcomm_event_extended_header *) comm_ext_at;
+ int probe_storage_req = 0;
+
+ comm_ext_at += sizeof(*ext_comm);
+ comm_ext_at += ext_comm->filter_len;
+ comm_ext_at +=
+ ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
+
+ if (ext_comm->userspace_probe_location_len) {
+ struct lttng_userspace_probe_location *probe_location = NULL;
+ struct lttng_buffer_view probe_location_view;
+
+ probe_location_view = lttng_buffer_view_init(
+ comm_ext_at, 0,
+ ext_comm->userspace_probe_location_len);
+
+ /*
+ * Create a temporary userspace probe location to
+ * determine the size needed by a "flattened" version
+ * of that same probe location.
+ */
+ ret = lttng_userspace_probe_location_create_from_buffer(
+ &probe_location_view, &probe_location);
+ if (ret < 0) {
+ ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+
+ ret = lttng_userspace_probe_location_flatten(
+ probe_location, NULL);
+ lttng_userspace_probe_location_destroy(probe_location);
+ if (ret < 0) {
+ ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+
+ probe_storage_req = ret;
+ comm_ext_at += ext_comm->userspace_probe_location_len;
+ }
+
+ storage_req += sizeof(struct lttng_event_extended);
+ storage_req += ext_comm->filter_len;
+ storage_req += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
+ /* Padding to ensure the flat probe is aligned. */
+ storage_req = ALIGN_TO(storage_req, sizeof(uint64_t));
+ storage_req += probe_storage_req;
+ }
+
+ lttng_dynamic_buffer_init(&listing);
+ /*
+ * We must ensure that "listing" is never resized so as to preserve
+ * the validity of the flattened objects.
+ */
+ ret = lttng_dynamic_buffer_set_capacity(&listing, storage_req);
+ if (ret) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ ret = lttng_dynamic_buffer_append(&listing, reception_buffer,
+ nb_events * sizeof(struct lttng_event));
+ if (ret) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto free_dynamic_buffer;
+ }
+
+ comm_ext_at = reception_buffer +
+ (nb_events * sizeof(struct lttng_event));
+ for (i = 0; i < nb_events; i++) {
+ struct lttng_event *event = (struct lttng_event *)
+ (listing.data + (sizeof(struct lttng_event) * i));
+ struct lttcomm_event_extended_header *ext_comm =
+ (struct lttcomm_event_extended_header *) comm_ext_at;
+ struct lttng_event_extended *event_extended =
+ (struct lttng_event_extended *)
+ (listing.data + listing.size);
+
+ /* Insert struct lttng_event_extended. */
+ ret = lttng_dynamic_buffer_set_size(&listing,
+ listing.size + sizeof(*event_extended));
+ if (ret) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto free_dynamic_buffer;
+ }
+ event->extended.ptr = event_extended;
+
+ comm_ext_at += sizeof(*ext_comm);
+
+ /* Insert filter expression. */
+ if (ext_comm->filter_len) {
+ event_extended->filter_expression = listing.data +
+ listing.size;
+ ret = lttng_dynamic_buffer_append(&listing, comm_ext_at,
+ ext_comm->filter_len);
+ if (ret) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto free_dynamic_buffer;
+ }
+ comm_ext_at += ext_comm->filter_len;
+ }
+
+ /* Insert exclusions. */
+ if (ext_comm->nb_exclusions) {
+ event_extended->exclusions.count =
+ ext_comm->nb_exclusions;
+ event_extended->exclusions.strings =
+ listing.data + listing.size;
+
+ ret = lttng_dynamic_buffer_append(&listing,
+ comm_ext_at,
+ ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN);
+ if (ret) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto free_dynamic_buffer;
+ }
+ comm_ext_at += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
+ }
+
+ /* Insert padding to align to 64-bits. */
+ ret = lttng_dynamic_buffer_set_size(&listing,
+ ALIGN_TO(listing.size, sizeof(uint64_t)));
+ if (ret) {
+ ret = -LTTNG_ERR_NOMEM;
+ goto free_dynamic_buffer;
+ }
+
+ /* Insert flattened userspace probe location. */
+ if (ext_comm->userspace_probe_location_len) {
+ struct lttng_userspace_probe_location *probe_location = NULL;
+ struct lttng_buffer_view probe_location_view;
+
+ probe_location_view = lttng_buffer_view_init(
+ comm_ext_at, 0,
+ ext_comm->userspace_probe_location_len);
+
+ ret = lttng_userspace_probe_location_create_from_buffer(
+ &probe_location_view, &probe_location);
+ if (ret < 0) {
+ ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto free_dynamic_buffer;
+ }
+
+ event_extended->probe_location = (struct lttng_userspace_probe_location *)
+ (listing.data + listing.size);
+ ret = lttng_userspace_probe_location_flatten(
+ probe_location, &listing);
+ lttng_userspace_probe_location_destroy(probe_location);
+ if (ret < 0) {
+ ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto free_dynamic_buffer;
+ }
+
+ comm_ext_at += ext_comm->userspace_probe_location_len;
+ }
+ }
+
+ /* Don't reset listing buffer as we return its content. */
+ *events = (struct lttng_event *) listing.data;
+ lttng_dynamic_buffer_init(&listing);
+ ret = (int) nb_events;
+free_dynamic_buffer:
+ lttng_dynamic_buffer_reset(&listing);
+end:
+ free(cmd_header);
+ free(reception_buffer);
+ return ret;
+}
+
+/*
+ * Sets the tracing_group variable with name.
+ * This function allocates memory pointed to by tracing_group.
+ * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
+ */
+int lttng_set_tracing_group(const char *name)
+{
+ if (name == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ if (asprintf(&tracing_group, "%s", name) < 0) {
+ return -LTTNG_ERR_FATAL;
+ }
+
+ return 0;
+}
+
+int lttng_calibrate(struct lttng_handle *handle,
+ struct lttng_calibrate *calibrate)
+{
+ /*
+ * This command was removed in LTTng 2.9.
+ */
+ return -LTTNG_ERR_UND;
+}
+
+/*
+ * Set default channel attributes.
+ * If either or both of the arguments are null, attr content is zeroe'd.
+ */
+void lttng_channel_set_default_attr(struct lttng_domain *domain,
+ struct lttng_channel_attr *attr)
+{
+ struct lttng_channel_extended *extended;
+
+ /* Safety check */
+ if (attr == NULL || domain == NULL) {
+ return;
+ }
+
+ extended = (struct lttng_channel_extended *) attr->extended.ptr;
+ memset(attr, 0, sizeof(struct lttng_channel_attr));
+
+ /* Same for all domains. */
+ attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
+ attr->tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
+ attr->tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT;
+
+ switch (domain->type) {
+ case LTTNG_DOMAIN_KERNEL:
+ attr->switch_timer_interval =
+ DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
+ attr->read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
+ attr->subbuf_size = default_get_kernel_channel_subbuf_size();
+ attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
+ attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
+ if (extended) {
+ extended->monitor_timer_interval =
+ DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER;
+ extended->blocking_timeout =
+ DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT;
+ }
+ break;
+ case LTTNG_DOMAIN_UST:
+ switch (domain->buf_type) {
+ case LTTNG_BUFFER_PER_UID:
+ attr->subbuf_size = default_get_ust_uid_channel_subbuf_size();
+ attr->num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM;
+ attr->output = DEFAULT_UST_UID_CHANNEL_OUTPUT;
+ attr->switch_timer_interval =
+ DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER;
+ attr->read_timer_interval =
+ DEFAULT_UST_UID_CHANNEL_READ_TIMER;
+ if (extended) {
+ extended->monitor_timer_interval =
+ DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER;
+ extended->blocking_timeout =
+ DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT;
+ }
+ break;
+ case LTTNG_BUFFER_PER_PID:
+ default:
+ attr->subbuf_size = default_get_ust_pid_channel_subbuf_size();
+ attr->num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM;
+ attr->output = DEFAULT_UST_PID_CHANNEL_OUTPUT;
+ attr->switch_timer_interval =
+ DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER;
+ attr->read_timer_interval =
+ DEFAULT_UST_PID_CHANNEL_READ_TIMER;
+ if (extended) {
+ extended->monitor_timer_interval =
+ DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER;
+ extended->blocking_timeout =
+ DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT;
+ }
+ break;
+ }
+ default:
+ /* Default behavior: leave set to 0. */
+ break;
+ }
+
+ attr->extended.ptr = extended;
+}
+
+int lttng_channel_get_discarded_event_count(struct lttng_channel *channel,
+ uint64_t *discarded_events)
+{
+ int ret = 0;
+ struct lttng_channel_extended *chan_ext;
+
+ if (!channel || !discarded_events) {
+ ret = -LTTNG_ERR_INVALID;
+ goto end;
+ }
+
+ chan_ext = channel->attr.extended.ptr;
+ if (!chan_ext) {
+ /*
+ * This can happen since the lttng_channel structure is
+ * used for other tasks where this pointer is never set.
+ */
+ *discarded_events = 0;
+ goto end;
+ }
+
+ *discarded_events = chan_ext->discarded_events;
+end:
+ return ret;
+}
+
+int lttng_channel_get_lost_packet_count(struct lttng_channel *channel,
+ uint64_t *lost_packets)
+{
+ int ret = 0;
+ struct lttng_channel_extended *chan_ext;
+
+ if (!channel || !lost_packets) {
+ ret = -LTTNG_ERR_INVALID;
+ goto end;
+ }
+
+ chan_ext = channel->attr.extended.ptr;
+ if (!chan_ext) {
+ /*
+ * This can happen since the lttng_channel structure is
+ * used for other tasks where this pointer is never set.
+ */
+ *lost_packets = 0;
+ goto end;
+ }
+
+ *lost_packets = chan_ext->lost_packets;
+end:
+ return ret;
+}
+
+int lttng_channel_get_monitor_timer_interval(struct lttng_channel *chan,
+ uint64_t *monitor_timer_interval)
+{
+ int ret = 0;