+
+static int lttng_event_probe_attr_serialize(
+ const struct lttng_event_probe_attr *probe,
+ struct lttng_payload *payload)
+{
+ int ret;
+ size_t symbol_name_len;
+ struct lttng_event_probe_attr_comm comm = { 0 };
+
+ symbol_name_len = lttng_strnlen(probe->symbol_name, LTTNG_SYMBOL_NAME_LEN);
+ if (symbol_name_len == LTTNG_SYMBOL_NAME_LEN) {
+ /* Not null-termintated. */
+ ret = -1;
+ goto end;
+ }
+
+ /* Include the null terminator. */
+ symbol_name_len += 1;
+
+ comm.symbol_name_len = (uint32_t) symbol_name_len;
+ comm.addr = probe->addr;
+ comm.offset = probe->addr;
+
+ ret = lttng_dynamic_buffer_append(
+ &payload->buffer, &comm, sizeof(comm));
+ if (ret < 0) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_dynamic_buffer_append(
+ &payload->buffer, probe->symbol_name, symbol_name_len);
+end:
+ return ret;
+}
+
+static int lttng_event_function_attr_serialize(
+ const struct lttng_event_function_attr *function,
+ struct lttng_payload *payload)
+{
+ int ret;
+ size_t symbol_name_len;
+ struct lttng_event_function_attr_comm comm = { 0 };
+
+ symbol_name_len = lttng_strnlen(function->symbol_name, LTTNG_SYMBOL_NAME_LEN);
+ if (symbol_name_len == LTTNG_SYMBOL_NAME_LEN) {
+ /* Not null-termintated. */
+ ret = -1;
+ goto end;
+ }
+
+ /* Include the null terminator. */
+ symbol_name_len += 1;
+
+ comm.symbol_name_len = (uint32_t) symbol_name_len;
+
+ ret = lttng_dynamic_buffer_append(
+ &payload->buffer, &comm, sizeof(comm));
+ if (ret < 0) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_dynamic_buffer_append(&payload->buffer,
+ function->symbol_name, symbol_name_len);
+end:
+ return ret;
+}
+
+static ssize_t lttng_event_probe_attr_create_from_payload(
+ struct lttng_payload_view *view,
+ struct lttng_event_probe_attr **probe_attr)
+{
+ ssize_t ret, offset = 0;
+ const struct lttng_event_probe_attr_comm *comm;
+ struct lttng_event_probe_attr *local_attr = NULL;
+ struct lttng_payload_view comm_view = lttng_payload_view_from_view(
+ view, offset, sizeof(*comm));
+
+ if (!lttng_payload_view_is_valid(&comm_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ comm = (typeof(comm)) comm_view.buffer.data;
+ offset += sizeof(*comm);
+
+ local_attr = (struct lttng_event_probe_attr *) zmalloc(
+ sizeof(*local_attr));
+ if (local_attr == NULL) {
+ ret = -1;
+ goto end;
+ }
+
+ local_attr->addr = comm->addr;
+ local_attr->offset = comm->offset;
+
+ {
+ const char *name;
+ struct lttng_payload_view name_view =
+ lttng_payload_view_from_view(view, offset,
+ comm->symbol_name_len);
+
+ if (!lttng_payload_view_is_valid(&name_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ name = name_view.buffer.data;
+
+ if (!lttng_buffer_view_contains_string(&name_view.buffer, name,
+ comm->symbol_name_len)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_strncpy(local_attr->symbol_name, name,
+ LTTNG_SYMBOL_NAME_LEN);
+ if (ret) {
+ ret = -1;
+ goto end;
+ }
+
+ offset += comm->symbol_name_len;
+ }
+
+ *probe_attr = local_attr;
+ local_attr = NULL;
+ ret = offset;
+end:
+ return ret;
+}
+
+static ssize_t lttng_event_function_attr_create_from_payload(
+ struct lttng_payload_view *view,
+ struct lttng_event_function_attr **function_attr)
+{
+ ssize_t ret, offset = 0;
+ const struct lttng_event_function_attr_comm *comm;
+ struct lttng_event_function_attr *local_attr = NULL;
+ struct lttng_payload_view comm_view = lttng_payload_view_from_view(
+ view, offset, sizeof(*comm));
+
+ if (!lttng_payload_view_is_valid(&comm_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ comm = (typeof(comm)) view->buffer.data;
+ offset += sizeof(*comm);
+
+ local_attr = (struct lttng_event_function_attr *) zmalloc(
+ sizeof(*local_attr));
+ if (local_attr == NULL) {
+ ret = -1;
+ goto end;
+ }
+
+ {
+ const char *name;
+ struct lttng_payload_view name_view =
+ lttng_payload_view_from_view(view, offset,
+ comm->symbol_name_len);
+
+ if (!lttng_payload_view_is_valid(&name_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ name = name_view.buffer.data;
+
+ if (!lttng_buffer_view_contains_string(&name_view.buffer, name,
+ comm->symbol_name_len)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_strncpy(local_attr->symbol_name, name,
+ LTTNG_SYMBOL_NAME_LEN);
+ if (ret) {
+ ret = -1;
+ goto end;
+ }
+
+ offset += comm->symbol_name_len;
+ }
+
+ *function_attr = local_attr;
+ local_attr = NULL;
+ ret = offset;
+end:
+ return ret;
+}
+
+static ssize_t lttng_event_exclusions_create_from_payload(
+ struct lttng_payload_view *view,
+ uint32_t count,
+ struct lttng_event_exclusion **exclusions)
+{
+ ssize_t ret, offset = 0;
+ size_t size = (count * LTTNG_SYMBOL_NAME_LEN);
+ uint32_t i;
+ const struct lttng_event_exclusion_comm *comm;
+ struct lttng_event_exclusion *local_exclusions;
+
+ local_exclusions = (struct lttng_event_exclusion *) zmalloc(
+ sizeof(struct lttng_event_exclusion) + size);
+ if (!local_exclusions) {
+ ret = -1;
+ goto end;
+ }
+
+ local_exclusions->count = count;
+
+ for (i = 0; i < count; i++) {
+ const char *string;
+ struct lttng_buffer_view string_view;
+ const struct lttng_buffer_view comm_view =
+ lttng_buffer_view_from_view(&view->buffer,
+ offset, sizeof(*comm));
+
+ if (!lttng_buffer_view_is_valid(&comm_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ comm = (typeof(comm)) comm_view.data;
+ offset += sizeof(*comm);
+
+ string_view = lttng_buffer_view_from_view(
+ &view->buffer, offset, comm->len);
+
+ if (!lttng_buffer_view_is_valid(&string_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ string = string_view.data;
+
+ if (!lttng_buffer_view_contains_string(
+ &string_view, string, comm->len)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_strncpy(local_exclusions->names[i],
+ string, LTTNG_SYMBOL_NAME_LEN);
+ if (ret) {
+ ret = -1;
+ goto end;
+ }
+
+ offset += comm->len;
+ }
+
+ *exclusions = local_exclusions;
+ local_exclusions = NULL;
+ ret = offset;
+end:
+ free(local_exclusions);
+ return ret;
+}
+
+ssize_t lttng_event_create_from_payload(struct lttng_payload_view *view,
+ struct lttng_event **out_event,
+ struct lttng_event_exclusion **out_exclusion,
+ char **out_filter_expression,
+ struct lttng_bytecode **out_bytecode)
+{
+ ssize_t ret, offset = 0;
+ struct lttng_event *local_event = NULL;
+ struct lttng_event_exclusion *local_exclusions = NULL;
+ struct lttng_bytecode *local_bytecode = NULL;
+ char *local_filter_expression = NULL;
+ const struct lttng_event_comm *event_comm;
+ struct lttng_event_function_attr *local_function_attr = NULL;
+ struct lttng_event_probe_attr *local_probe_attr = NULL;
+ struct lttng_userspace_probe_location *local_userspace_probe_location =
+ NULL;
+
+ /*
+ * Only event is obligatory, the other output argument are optional and
+ * depends on what the caller is interested in.
+ */
+ assert(out_event);
+ assert(view);
+
+ {
+ struct lttng_payload_view comm_view =
+ lttng_payload_view_from_view(view, offset,
+ sizeof(*event_comm));
+
+ if (!lttng_payload_view_is_valid(&comm_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ /* lttng_event_comm header */
+ event_comm = (typeof(event_comm)) comm_view.buffer.data;
+ offset += sizeof(*event_comm);
+ }
+
+ local_event = lttng_event_create();
+ if (local_event == NULL) {
+ ret = -1;
+ goto end;
+ }
+
+ local_event->type = (enum lttng_event_type) event_comm->event_type;
+ local_event->loglevel_type = (enum lttng_loglevel_type) event_comm->loglevel_type;
+ local_event->loglevel = event_comm->loglevel;
+ local_event->enabled = event_comm->enabled;
+ local_event->pid = event_comm->pid;
+ local_event->flags = (enum lttng_event_flag) event_comm->flags;
+
+ {
+ const char *name;
+ const struct lttng_buffer_view name_view =
+ lttng_buffer_view_from_view(&view->buffer,
+ offset, event_comm->name_len);
+
+ if (!lttng_buffer_view_is_valid(&name_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ name = (const char *) name_view.data;
+
+ if (!lttng_buffer_view_contains_string(
+ &name_view, name, event_comm->name_len)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_strncpy(
+ local_event->name, name, LTTNG_SYMBOL_NAME_LEN);
+ if (ret) {
+ ret = -1;
+ goto end;
+ }
+
+ offset += event_comm->name_len;
+ }
+
+ /* Exclusions */
+ if (event_comm->exclusion_count == 0) {
+ goto deserialize_filter_expression;
+ }
+
+ {
+ struct lttng_payload_view exclusions_view =
+ lttng_payload_view_from_view(
+ view, offset, -1);
+
+ if (!lttng_payload_view_is_valid(&exclusions_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_event_exclusions_create_from_payload(&exclusions_view,
+ event_comm->exclusion_count, &local_exclusions);
+ if (ret < 0) {
+ ret = -1;
+ goto end;
+ }
+ offset += ret;
+
+ local_event->exclusion = 1;
+ }
+
+deserialize_filter_expression:
+
+ if (event_comm->filter_expression_len == 0) {
+ if (event_comm->bytecode_len != 0) {
+ /*
+ * This is an invalid event payload.
+ *
+ * Filter expression without bytecode is possible but
+ * not the other way around.
+ * */
+ ret = -1;
+ goto end;
+ }
+ goto deserialize_event_type_payload;
+ }
+
+ {
+ const char *filter_expression_buffer;
+ struct lttng_buffer_view filter_expression_view =
+ lttng_buffer_view_from_view(&view->buffer, offset,
+ event_comm->filter_expression_len);
+
+ if (!lttng_buffer_view_is_valid(&filter_expression_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ filter_expression_buffer = filter_expression_view.data;
+
+ if (!lttng_buffer_view_contains_string(&filter_expression_view,
+ filter_expression_buffer,
+ event_comm->filter_expression_len)) {
+ ret = -1;
+ goto end;
+ }
+
+ local_filter_expression = lttng_strndup(
+ filter_expression_buffer,
+ event_comm->filter_expression_len);
+ if (!local_filter_expression) {
+ ret = -1;
+ goto end;
+ }
+
+ local_event->filter = 1;
+
+ offset += event_comm->filter_expression_len;
+ }
+
+ if (event_comm->bytecode_len == 0) {
+ /*
+ * Filter expression can be present but without bytecode
+ * when dealing with event listing.
+ */
+ goto deserialize_event_type_payload;
+ }
+
+ /* Bytecode */
+ {
+ struct lttng_payload_view bytecode_view =
+ lttng_payload_view_from_view(view, offset,
+ event_comm->bytecode_len);
+
+ if (!lttng_payload_view_is_valid(&bytecode_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ local_bytecode = (struct lttng_bytecode *) zmalloc(
+ event_comm->bytecode_len);
+ if (!local_bytecode) {
+ ret = -1;
+ goto end;
+ }
+
+ memcpy(local_bytecode, bytecode_view.buffer.data,
+ event_comm->bytecode_len);
+ if ((local_bytecode->len + sizeof(*local_bytecode)) !=
+ event_comm->bytecode_len) {
+ ret = -1;
+ goto end;
+ }
+
+ offset += event_comm->bytecode_len;
+ }
+
+deserialize_event_type_payload:
+ /* Event type specific payload */
+ switch (local_event->type) {
+ case LTTNG_EVENT_FUNCTION:
+ /* Fallthrough */
+ case LTTNG_EVENT_PROBE:
+ {
+ struct lttng_payload_view probe_attr_view =
+ lttng_payload_view_from_view(view, offset,
+ event_comm->lttng_event_probe_attr_len);
+
+ if (event_comm->lttng_event_probe_attr_len == 0) {
+ ret = -1;
+ goto end;
+ }
+
+ if (!lttng_payload_view_is_valid(&probe_attr_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_event_probe_attr_create_from_payload(
+ &probe_attr_view, &local_probe_attr);
+ if (ret < 0 || ret != event_comm->lttng_event_probe_attr_len) {
+ ret = -1;
+ goto end;
+ }
+
+ /* Copy to the local event. */
+ memcpy(&local_event->attr.probe, local_probe_attr,
+ sizeof(local_event->attr.probe));
+
+ offset += ret;
+ break;
+ }
+ case LTTNG_EVENT_FUNCTION_ENTRY:
+ {
+ struct lttng_payload_view function_attr_view =
+ lttng_payload_view_from_view(view, offset,
+ event_comm->lttng_event_function_attr_len);
+
+ if (event_comm->lttng_event_function_attr_len == 0) {
+ ret = -1;
+ goto end;
+ }
+
+ if (!lttng_payload_view_is_valid(&function_attr_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_event_function_attr_create_from_payload(
+ &function_attr_view, &local_function_attr);
+ if (ret < 0 || ret != event_comm->lttng_event_function_attr_len) {
+ ret = -1;
+ goto end;
+ }
+
+ /* Copy to the local event. */
+ memcpy(&local_event->attr.ftrace, local_function_attr,
+ sizeof(local_event->attr.ftrace));
+
+ offset += ret;
+
+ break;
+ }
+ case LTTNG_EVENT_USERSPACE_PROBE:
+ {
+ struct lttng_payload_view userspace_probe_location_view =
+ lttng_payload_view_from_view(view, offset,
+ event_comm->userspace_probe_location_len);
+
+ if (event_comm->userspace_probe_location_len == 0) {
+ ret = -1;
+ goto end;
+ }
+
+ if (!lttng_payload_view_is_valid(
+ &userspace_probe_location_view)) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_userspace_probe_location_create_from_payload(
+ &userspace_probe_location_view,
+ &local_userspace_probe_location);
+ if (ret < 0) {
+ WARN("Failed to create a userspace probe location from the received buffer");
+ ret = -1;
+ goto end;
+ }
+
+ if (ret != event_comm->userspace_probe_location_len) {
+ WARN("Userspace probe location from the received buffer is not the advertised length: header length = %" PRIu32 ", payload length = %lu", event_comm->userspace_probe_location_len, ret);
+ ret = -1;
+ goto end;
+ }
+
+ /* Attach the probe location to the event. */
+ ret = lttng_event_set_userspace_probe_location(
+ local_event, local_userspace_probe_location);
+ if (ret) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+
+ /*
+ * Userspace probe location object ownership transfered to the
+ * event object.
+ */
+ local_userspace_probe_location = NULL;
+ offset += event_comm->userspace_probe_location_len;
+ break;
+ }
+ case LTTNG_EVENT_TRACEPOINT:
+ /* Fallthrough */
+ case LTTNG_EVENT_ALL:
+ /* Fallthrough */
+ case LTTNG_EVENT_SYSCALL:
+ /* Fallthrough */
+ case LTTNG_EVENT_NOOP:
+ /* Nothing to do here */
+ break;
+ default:
+ ret = LTTNG_ERR_UND;
+ goto end;
+ break;
+ }
+
+ /* Transfer ownership to the caller. */
+ *out_event = local_event;
+ local_event = NULL;
+
+ if (out_bytecode) {
+ *out_bytecode = local_bytecode;
+ local_bytecode = NULL;
+ }
+
+ if (out_exclusion) {
+ *out_exclusion = local_exclusions;
+ local_exclusions = NULL;
+ }
+
+ if (out_filter_expression) {
+ *out_filter_expression = local_filter_expression;
+ local_filter_expression = NULL;
+ }
+
+ ret = offset;
+end:
+ lttng_event_destroy(local_event);
+ lttng_userspace_probe_location_destroy(local_userspace_probe_location);
+ free(local_filter_expression);
+ free(local_exclusions);
+ free(local_bytecode);
+ free(local_function_attr);
+ free(local_probe_attr);
+ return ret;
+}
+
+int lttng_event_serialize(const struct lttng_event *event,
+ unsigned int exclusion_count,
+ char **exclusion_list,
+ char *filter_expression,
+ size_t bytecode_len,
+ struct lttng_bytecode *bytecode,
+ struct lttng_payload *payload)
+{
+ int ret;
+ unsigned int i;
+ size_t header_offset, size_before_payload;
+ size_t name_len;
+ struct lttng_event_comm event_comm = { 0 };
+ struct lttng_event_comm *header;
+
+ assert(event);
+ assert(payload);
+ assert(exclusion_count == 0 || exclusion_list);
+
+ /* Save the header location for later in-place header update. */
+ header_offset = payload->buffer.size;
+
+ name_len = lttng_strnlen(event->name, LTTNG_SYMBOL_NAME_LEN);
+ if (name_len == LTTNG_SYMBOL_NAME_LEN) {
+ /* Event name is not NULL-terminated. */
+ ret = -1;
+ goto end;
+ }
+
+ /* Add null termination. */
+ name_len += 1;
+
+ if (exclusion_count > UINT32_MAX) {
+ /* Possible overflow. */
+ ret = -1;
+ goto end;
+ }
+
+ if (bytecode_len > UINT32_MAX) {
+ /* Possible overflow. */
+ ret = -1;
+ goto end;
+ }
+
+ event_comm.name_len = (uint32_t) name_len;
+ event_comm.event_type = (int8_t) event->type;
+ event_comm.loglevel_type = (int8_t) event->loglevel_type;
+ event_comm.loglevel = (int32_t) event->loglevel;
+ event_comm.enabled = (int8_t) event->enabled;
+ event_comm.pid = (int32_t) event->pid;
+ event_comm.exclusion_count = (uint32_t) exclusion_count;
+ event_comm.bytecode_len = (uint32_t) bytecode_len;
+ event_comm.flags = (int32_t) event->flags;
+
+ if (filter_expression) {
+ event_comm.filter_expression_len =
+ strlen(filter_expression) + 1;
+ }
+
+ /* Header */
+ ret = lttng_dynamic_buffer_append(
+ &payload->buffer, &event_comm, sizeof(event_comm));
+ if (ret) {
+ goto end;
+ }
+
+ /* Event name */
+ ret = lttng_dynamic_buffer_append(
+ &payload->buffer, event->name, name_len);
+ if (ret) {
+ goto end;
+ }
+
+ /* Exclusions */
+ for (i = 0; i < exclusion_count; i++) {
+ const size_t exclusion_len = lttng_strnlen(
+ *(exclusion_list + i), LTTNG_SYMBOL_NAME_LEN);
+ const struct lttng_event_exclusion_comm exclusion_header = {
+ .len = (uint32_t) exclusion_len + 1,
+ };
+
+ if (exclusion_len == LTTNG_SYMBOL_NAME_LEN) {
+ /* Exclusion is not NULL-terminated. */
+ ret = -1;
+ goto end;
+ }
+
+ ret = lttng_dynamic_buffer_append(&payload->buffer,
+ &exclusion_header, sizeof(exclusion_header));
+ if (ret) {
+ goto end;
+ }
+
+ ret = lttng_dynamic_buffer_append(&payload->buffer,
+ *(exclusion_list + i), exclusion_len + 1);
+ if (ret) {
+ goto end;
+ }
+ }
+
+ /* Filter expression and its bytecode */
+ if (filter_expression) {
+ ret = lttng_dynamic_buffer_append(&payload->buffer,
+ filter_expression,
+ event_comm.filter_expression_len);
+ if (ret) {
+ goto end;
+ }
+
+ /*
+ * Bytecode can be absent when we serialize to the client
+ * for listing.
+ */
+ if (bytecode) {
+ ret = lttng_dynamic_buffer_append(&payload->buffer,
+ bytecode, bytecode_len);
+ if (ret) {
+ goto end;
+ }
+ }
+ }
+
+ size_before_payload = payload->buffer.size;
+
+ /* Event type specific payload */
+ switch (event->type) {
+ case LTTNG_EVENT_FUNCTION:
+ /* Fallthrough */
+ case LTTNG_EVENT_PROBE:
+ ret = lttng_event_probe_attr_serialize(&event->attr.probe, payload);
+ if (ret) {
+ ret = -1;
+ goto end;
+ }
+
+ header = (struct lttng_event_comm *) ((char *) payload->buffer.data +
+ header_offset);
+ header->lttng_event_probe_attr_len =
+ payload->buffer.size - size_before_payload;
+
+ break;
+ case LTTNG_EVENT_FUNCTION_ENTRY:
+ ret = lttng_event_function_attr_serialize(
+ &event->attr.ftrace, payload);
+ if (ret) {
+ ret = -1;
+ goto end;
+ }
+
+ /* Update the lttng_event_function_attr len. */
+ header = (struct lttng_event_comm *) ((char *) payload->buffer.data +
+ header_offset);
+ header->lttng_event_function_attr_len =
+ payload->buffer.size - size_before_payload;
+
+ break;
+ case LTTNG_EVENT_USERSPACE_PROBE:
+ {
+ const struct lttng_event_extended *ev_ext =
+ (const struct lttng_event_extended *)
+ event->extended.ptr;
+
+ assert(event->extended.ptr);
+ assert(ev_ext->probe_location);
+
+ size_before_payload = payload->buffer.size;
+ if (ev_ext->probe_location) {
+ /*
+ * lttng_userspace_probe_location_serialize returns the
+ * number of bytes that were appended to the buffer.
+ */
+ ret = lttng_userspace_probe_location_serialize(
+ ev_ext->probe_location, payload);
+ if (ret < 0) {
+ goto end;
+ }
+
+ ret = 0;
+
+ /* Update the userspace probe location len. */
+ header = (struct lttng_event_comm *) ((char *) payload->buffer.data +
+ header_offset);
+ header->userspace_probe_location_len =
+ payload->buffer.size - size_before_payload;
+ }
+ break;
+ }
+ case LTTNG_EVENT_TRACEPOINT:
+ /* Fallthrough */
+ case LTTNG_EVENT_ALL:
+ /* Fallthrough */
+ default:
+ /* Nothing to do here. */
+ break;
+ }
+
+end:
+ return ret;
+}
+
+static enum lttng_error_code compute_flattened_size(
+ struct lttng_dynamic_pointer_array *events, size_t *size)
+{
+ enum lttng_error_code ret_code;
+ int ret = 0;
+ size_t storage_req, event_count, i;
+
+ assert(size);
+ assert(events);
+
+ event_count = lttng_dynamic_pointer_array_get_count(events);
+
+ /* The basic struct lttng_event */
+ storage_req = event_count * sizeof(struct lttng_event);
+
+ for (i = 0; i < event_count; i++) {
+ int probe_storage_req = 0;
+ const struct event_list_element *element = (const struct event_list_element *)
+ lttng_dynamic_pointer_array_get_pointer(
+ events, i);
+ const struct lttng_userspace_probe_location *location = NULL;
+
+ location = lttng_event_get_userspace_probe_location(
+ element->event);
+ if (location) {
+ ret = lttng_userspace_probe_location_flatten(
+ location, NULL);
+ if (ret < 0) {
+ ret_code = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+
+ probe_storage_req = ret;
+ }
+
+ /* The struct·lttng_event_extended */
+ storage_req += event_count *
+ sizeof(struct lttng_event_extended);
+
+ if (element->filter_expression) {
+ storage_req += strlen(element->filter_expression) + 1;
+ }
+
+ if (element->exclusions) {
+ storage_req += element->exclusions->count *
+ LTTNG_SYMBOL_NAME_LEN;
+ }
+
+ /* Padding to ensure the flat probe is aligned. */
+ storage_req = lttng_align_ceil(storage_req, sizeof(uint64_t));
+ storage_req += probe_storage_req;
+ }
+
+ *size = storage_req;
+ ret_code = LTTNG_OK;
+
+end:
+ return ret_code;
+}
+
+/*
+ * Flatten a list of struct lttng_event.
+ *
+ * The buffer that is returned to the API client 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,
+ * - filter_expression
+ * - exclusions
+ * - padding to align to 64-bits
+ * - flattened version of userspace_probe_location
+ */
+static enum lttng_error_code flatten_lttng_events(
+ struct lttng_dynamic_pointer_array *events,
+ struct lttng_event **flattened_events)
+{
+ enum lttng_error_code ret_code;
+ int ret, i;
+ size_t storage_req;
+ struct lttng_dynamic_buffer local_flattened_events;
+ int nb_events;
+
+ assert(events);
+ assert(flattened_events);
+
+ lttng_dynamic_buffer_init(&local_flattened_events);
+ nb_events = lttng_dynamic_pointer_array_get_count(events);
+
+ ret_code = compute_flattened_size(events, &storage_req);
+ if (ret_code != LTTNG_OK) {
+ goto end;
+ }
+
+ /*
+ * We must ensure that "local_flattened_events" is never resized so as
+ * to preserve the validity of the flattened objects.
+ */
+ ret = lttng_dynamic_buffer_set_capacity(
+ &local_flattened_events, storage_req);
+ if (ret) {
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ /* Start by laying the struct lttng_event */
+ for (i = 0; i < nb_events; i++) {
+ const struct event_list_element *element = (const struct event_list_element *)
+ lttng_dynamic_pointer_array_get_pointer(
+ events, i);
+
+ if (!element) {
+ ret_code = LTTNG_ERR_FATAL;
+ goto end;
+ }
+
+ ret = lttng_dynamic_buffer_append(&local_flattened_events,
+ element->event, sizeof(struct lttng_event));
+ if (ret) {
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+ }
+
+ for (i = 0; i < nb_events; i++) {
+ const struct event_list_element *element = (const struct event_list_element *)
+ lttng_dynamic_pointer_array_get_pointer(events, i);
+ struct lttng_event *event = (struct lttng_event *)
+ (local_flattened_events.data + (sizeof(struct lttng_event) * i));
+ struct lttng_event_extended *event_extended =
+ (struct lttng_event_extended *)
+ (local_flattened_events.data + local_flattened_events.size);
+ const struct lttng_userspace_probe_location *location = NULL;
+
+ assert(element);
+
+ /* Insert struct lttng_event_extended. */
+ ret = lttng_dynamic_buffer_set_size(&local_flattened_events,
+ local_flattened_events.size +
+ sizeof(*event_extended));
+ if (ret) {
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+ event->extended.ptr = event_extended;
+
+ /* Insert filter expression. */
+ if (element->filter_expression) {
+ const size_t len = strlen(element->filter_expression) + 1;
+
+ event_extended->filter_expression =
+ local_flattened_events.data +
+ local_flattened_events.size;
+ ret = lttng_dynamic_buffer_append(
+ &local_flattened_events,
+ element->filter_expression, len);
+ if (ret) {
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+ }
+
+ /* Insert exclusions. */
+ if (element->exclusions) {
+ event_extended->exclusions.count =
+ element->exclusions->count;
+ event_extended->exclusions.strings =
+ local_flattened_events.data +
+ local_flattened_events.size;
+
+ ret = lttng_dynamic_buffer_append(
+ &local_flattened_events,
+ element->exclusions->names,
+ element->exclusions->count *
+ LTTNG_SYMBOL_NAME_LEN);
+ if (ret) {
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+ }
+
+ /* Insert padding to align to 64-bits. */
+ ret = lttng_dynamic_buffer_set_size(&local_flattened_events,
+ lttng_align_ceil(local_flattened_events.size,
+ sizeof(uint64_t)));
+ if (ret) {
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ location = lttng_event_get_userspace_probe_location(
+ element->event);
+ if (location) {
+ event_extended->probe_location = (struct lttng_userspace_probe_location *)
+ (local_flattened_events.data + local_flattened_events.size);
+ ret = lttng_userspace_probe_location_flatten(
+ location, &local_flattened_events);
+ if (ret < 0) {
+ ret_code = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto end;
+ }
+ }
+ }
+
+ /* Don't reset local_flattened_events buffer as we return its content. */
+ *flattened_events = (struct lttng_event *) local_flattened_events.data;
+ lttng_dynamic_buffer_init(&local_flattened_events);
+ ret_code = LTTNG_OK;
+end:
+ lttng_dynamic_buffer_reset(&local_flattened_events);
+ return ret_code;
+}
+
+static enum lttng_error_code event_list_create_from_payload(
+ struct lttng_payload_view *view,
+ unsigned int count,
+ struct lttng_dynamic_pointer_array *event_list)
+{
+ enum lttng_error_code ret_code;
+ int ret;
+ unsigned int i;
+ int offset = 0;
+
+ assert(view);
+ assert(event_list);
+
+ for (i = 0; i < count; i++) {
+ ssize_t event_size;
+ struct lttng_payload_view event_view =
+ lttng_payload_view_from_view(view, offset, -1);
+ struct event_list_element *element =
+ (struct event_list_element *) zmalloc(sizeof(*element));
+
+ if (!element) {
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ /*
+ * Lifetime and management of the object is now bound to the
+ * array.
+ */
+ ret = lttng_dynamic_pointer_array_add_pointer(
+ event_list, element);
+ if (ret) {
+ event_list_destructor(element);
+ ret_code = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+
+ /*
+ * Bytecode is not transmitted on listing in any case we do not
+ * care about it.
+ */
+ event_size = lttng_event_create_from_payload(&event_view,
+ &element->event,
+ &element->exclusions,
+ &element->filter_expression, NULL);
+ if (event_size < 0) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+
+ offset += event_size;
+ }
+
+ if (view->buffer.size != offset) {
+ ret_code = LTTNG_ERR_INVALID_PROTOCOL;
+ goto end;
+ }
+
+ ret_code = LTTNG_OK;
+
+end:
+ return ret_code;
+}
+
+enum lttng_error_code lttng_events_create_and_flatten_from_payload(
+ struct lttng_payload_view *payload,
+ unsigned int count,
+ struct lttng_event **events)
+{
+ enum lttng_error_code ret = LTTNG_OK;
+ struct lttng_dynamic_pointer_array local_events;
+
+ lttng_dynamic_pointer_array_init(&local_events, event_list_destructor);
+
+ /* Deserialize the events. */
+ {
+ struct lttng_payload_view events_view =
+ lttng_payload_view_from_view(payload, 0, -1);
+
+ ret = event_list_create_from_payload(
+ &events_view, count, &local_events);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ }
+
+ ret = flatten_lttng_events(&local_events, events);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+
+end:
+ lttng_dynamic_pointer_array_reset(&local_events);
+ return ret;
+}