[babeltrace.git] / src / ctf-writer / stream-class.c

/*
 * Copyright 2013, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com>
 * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#define BT_LOG_TAG "CTF-WRITER/STREAM-CLASS"
#include "logging.h"

#include <inttypes.h>
#include <stdbool.h>
#include <stdint.h>

#include <babeltrace2/ctf-writer/event.h>
#include <babeltrace2/ctf-writer/object.h>
#include <babeltrace2/ctf-writer/trace.h>
#include <babeltrace2/ctf-writer/utils.h>

#include "common/align.h"
#include "common/assert.h"
#include "compat/compiler.h"
#include "compat/endian.h"

#include "assert-pre.h"
#include "clock-class.h"
#include "event-class.h"
#include "event.h"
#include "fields.h"
#include "field-types.h"
#include "field-wrapper.h"
#include "stream-class.h"
#include "utils.h"
#include "validation.h"
#include "visitor.h"
#include "writer.h"

BT_HIDDEN
int bt_ctf_stream_class_common_initialize(struct bt_ctf_stream_class_common *stream_class,
		const char *name, bt_ctf_object_release_func release_func)
{
	BT_LOGD("Initializing common stream class object: name=\"%s\"", name);

	bt_ctf_object_init_shared_with_parent(&stream_class->base, release_func);
	stream_class->name = g_string_new(name);
	stream_class->event_classes = g_ptr_array_new_with_free_func(
		(GDestroyNotify) bt_ctf_object_try_spec_release);
	if (!stream_class->event_classes) {
		BT_LOGE_STR("Failed to allocate a GPtrArray.");
		goto error;
	}

	stream_class->event_classes_ht = g_hash_table_new_full(g_int64_hash,
			g_int64_equal, g_free, NULL);
	if (!stream_class->event_classes_ht) {
		BT_LOGE_STR("Failed to allocate a GHashTable.");
		goto error;
	}

	BT_LOGD("Initialized common stream class object: addr=%p, name=\"%s\"",
		stream_class, name);
	return 0;

error:
	return -1;
}

BT_HIDDEN
void bt_ctf_stream_class_common_finalize(struct bt_ctf_stream_class_common *stream_class)
{
	BT_LOGD("Finalizing common stream class: addr=%p, name=\"%s\", id=%" PRId64,
		stream_class, bt_ctf_stream_class_common_get_name(stream_class),
		bt_ctf_stream_class_common_get_id(stream_class));
	bt_ctf_object_put_ref(stream_class->clock_class);

	if (stream_class->event_classes_ht) {
		g_hash_table_destroy(stream_class->event_classes_ht);
	}
	if (stream_class->event_classes) {
		BT_LOGD_STR("Destroying event classes.");
		g_ptr_array_free(stream_class->event_classes, TRUE);
	}

	if (stream_class->name) {
		g_string_free(stream_class->name, TRUE);
	}

	BT_LOGD_STR("Putting event header field type.");
	bt_ctf_object_put_ref(stream_class->event_header_field_type);
	BT_LOGD_STR("Putting packet context field type.");
	bt_ctf_object_put_ref(stream_class->packet_context_field_type);
	BT_LOGD_STR("Putting event context field type.");
	bt_ctf_object_put_ref(stream_class->event_context_field_type);
}

static
void event_class_exists(gpointer element, gpointer query)
{
	struct bt_ctf_event_class_common *event_class_a = element;
	struct bt_ctf_search_query *search_query = query;
	struct bt_ctf_event_class_common *event_class_b = search_query->value;
	int64_t id_a, id_b;

	if (search_query->value == element) {
		search_query->found = 1;
		goto end;
	}

	/*
	 * Two event classes cannot share the same ID in a given
	 * stream class.
	 */
	id_a = bt_ctf_event_class_common_get_id(event_class_a);
	id_b = bt_ctf_event_class_common_get_id(event_class_b);

	if (id_a < 0 || id_b < 0) {
		/* at least one ID is not set: will be automatically set later */
		goto end;
	}

	if (id_a == id_b) {
		BT_LOGW("Event class with this ID already exists in the stream class: "
			"id=%" PRId64 ", name=\"%s\"",
			id_a, bt_ctf_event_class_common_get_name(event_class_a));
		search_query->found = 1;
		goto end;
	}

end:
	return;
}

BT_HIDDEN
int bt_ctf_stream_class_common_add_event_class(
		struct bt_ctf_stream_class_common *stream_class,
		struct bt_ctf_event_class_common *event_class,
		bt_ctf_validation_flag_copy_field_type_func copy_field_type_func)
{
	int ret = 0;
	int64_t *event_id = NULL;
	struct bt_ctf_trace_common *trace = NULL;
	struct bt_ctf_stream_class_common *old_stream_class = NULL;
	struct bt_ctf_validation_output validation_output = { 0 };
	struct bt_ctf_field_type_common *packet_header_type = NULL;
	struct bt_ctf_field_type_common *packet_context_type = NULL;
	struct bt_ctf_field_type_common *event_header_type = NULL;
	struct bt_ctf_field_type_common *stream_event_ctx_type = NULL;
	struct bt_ctf_field_type_common *event_context_type = NULL;
	struct bt_ctf_field_type_common *event_payload_type = NULL;
	const enum bt_ctf_validation_flag validation_flags =
		BT_CTF_VALIDATION_FLAG_EVENT;
	struct bt_ctf_clock_class *expected_clock_class = NULL;

	BT_ASSERT(copy_field_type_func);

	if (!stream_class || !event_class) {
		BT_LOGW("Invalid parameter: stream class or event class is NULL: "
			"stream-class-addr=%p, event-class-addr=%p",
			stream_class, event_class);
		ret = -1;
		goto end;
	}

	BT_LOGD("Adding event class to stream class: "
		"stream-class-addr=%p, stream-class-name=\"%s\", "
		"stream-class-id=%" PRId64 ", event-class-addr=%p, "
		"event-class-name=\"%s\", event-class-id=%" PRId64,
		stream_class, bt_ctf_stream_class_common_get_name(stream_class),
		bt_ctf_stream_class_common_get_id(stream_class),
		event_class,
		bt_ctf_event_class_common_get_name(event_class),
		bt_ctf_event_class_common_get_id(event_class));
	trace = bt_ctf_stream_class_common_borrow_trace(stream_class);

	if (stream_class->frozen) {
		/*
		 * We only check that the event class to be added has a
		 * single class which matches the stream class's
		 * expected clock class if the stream class is frozen.
		 * If it's not, then this event class is added "as is"
		 * and the validation will be performed when calling
		 * either bt_ctf_trace_add_stream_class() or
		 * bt_ctf_event_create(). This is because the stream class's
		 * field types (packet context, event header, event
		 * context) could change before the next call to one of
		 * those two functions.
		 */
		expected_clock_class = bt_ctf_object_get_ref(stream_class->clock_class);

		/*
		 * At this point, `expected_clock_class` can be NULL,
		 * and bt_ctf_event_class_validate_single_clock_class()
		 * below can set it.
		 */
		ret = bt_ctf_event_class_common_validate_single_clock_class(
			event_class, &expected_clock_class);
		if (ret) {
			BT_LOGW("Event class contains a field type which is not "
				"recursively mapped to its stream class's "
				"expected clock class: "
				"stream-class-addr=%p, "
				"stream-class-id=%" PRId64 ", "
				"stream-class-name=\"%s\", "
				"expected-clock-class-addr=%p, "
				"expected-clock-class-name=\"%s\"",
				stream_class,
				bt_ctf_stream_class_common_get_id(stream_class),
				bt_ctf_stream_class_common_get_name(stream_class),
				expected_clock_class,
				expected_clock_class ?
					bt_ctf_clock_class_get_name(expected_clock_class) :
					NULL);
			goto end;
		}
	}

	event_id = g_new(int64_t, 1);
	if (!event_id) {
		BT_LOGE_STR("Failed to allocate one int64_t.");
		ret = -1;
		goto end;
	}

	/* Check for duplicate event classes */
	struct bt_ctf_search_query query = { .value = event_class, .found = 0 };
	g_ptr_array_foreach(stream_class->event_classes, event_class_exists,
		&query);
	if (query.found) {
		BT_LOGW_STR("Another event class part of this stream class has the same ID.");
		ret = -1;
		goto end;
	}

	old_stream_class = bt_ctf_event_class_common_borrow_stream_class(event_class);
	if (old_stream_class) {
		/* Event class is already associated to a stream class. */
		BT_LOGW("Event class is already part of another stream class: "
			"event-class-stream-class-addr=%p, "
			"event-class-stream-class-name=\"%s\", "
			"event-class-stream-class-id=%" PRId64,
			old_stream_class,
			bt_ctf_stream_class_common_get_name(old_stream_class),
			bt_ctf_stream_class_common_get_id(old_stream_class));
		ret = -1;
		goto end;
	}

	if (trace) {
		/*
		 * If the stream class is associated with a trace, then
		 * both those objects are frozen. Also, this event class
		 * is about to be frozen.
		 *
		 * Therefore the event class must be validated here.
		 * The trace and stream class should be valid at this
		 * point.
		 */
		BT_ASSERT(trace->valid);
		BT_ASSERT(stream_class->valid);
		packet_header_type =
			bt_ctf_trace_common_borrow_packet_header_field_type(trace);
		packet_context_type =
			bt_ctf_stream_class_common_borrow_packet_context_field_type(
				stream_class);
		event_header_type =
			bt_ctf_stream_class_common_borrow_event_header_field_type(
				stream_class);
		stream_event_ctx_type =
			bt_ctf_stream_class_common_borrow_event_context_field_type(
				stream_class);
		event_context_type =
			bt_ctf_event_class_common_borrow_context_field_type(
				event_class);
		event_payload_type =
			bt_ctf_event_class_common_borrow_payload_field_type(
				event_class);
		ret = bt_ctf_validate_class_types(
			trace->environment, packet_header_type,
			packet_context_type, event_header_type,
			stream_event_ctx_type, event_context_type,
			event_payload_type, trace->valid,
			stream_class->valid, event_class->valid,
			&validation_output, validation_flags,
			copy_field_type_func);

		if (ret) {
			/*
			 * This means something went wrong during the
			 * validation process, not that the objects are
			 * invalid.
			 */
			BT_LOGE("Failed to validate event class: ret=%d", ret);
			goto end;
		}

		if ((validation_output.valid_flags & validation_flags) !=
				validation_flags) {
			/* Invalid event class */
			BT_LOGW("Invalid trace, stream class, or event class: "
				"valid-flags=0x%x",
				validation_output.valid_flags);
			ret = -1;
			goto end;
		}
	}

	/* Only set an event ID if none was explicitly set before */
	*event_id = bt_ctf_event_class_common_get_id(event_class);
	if (*event_id < 0) {
		BT_LOGT("Event class has no ID: automatically setting it: "
			"id=%" PRId64, stream_class->next_event_id);

		if (bt_ctf_event_class_common_set_id(event_class,
				stream_class->next_event_id)) {
			BT_LOGE("Cannot set event class's ID: id=%" PRId64,
				stream_class->next_event_id);
			ret = -1;
			goto end;
		}
		stream_class->next_event_id++;
		*event_id = stream_class->next_event_id;
	}

	bt_ctf_object_set_parent(&event_class->base, &stream_class->base);

	if (trace) {
		/*
		 * At this point we know that the function will be
		 * successful. Therefore we can replace the event
		 * class's field types with what's in the validation
		 * output structure and mark this event class as valid.
		 */
		bt_ctf_validation_replace_types(NULL, NULL, event_class,
			&validation_output, validation_flags);
		event_class->valid = 1;

		/*
		 * Put what was not moved in
		 * bt_ctf_validation_replace_types().
		 */
		bt_ctf_validation_output_put_types(&validation_output);
	}

	/* Add to the event classes of the stream class */
	g_ptr_array_add(stream_class->event_classes, event_class);
	g_hash_table_insert(stream_class->event_classes_ht, event_id,
			event_class);
	event_id = NULL;

	/* Freeze the event class */
	bt_ctf_event_class_common_freeze(event_class);

	/*
	 * It is safe to set the stream class's unique clock class
	 * now if the stream class is frozen.
	 */
	if (stream_class->frozen && expected_clock_class) {
		BT_ASSERT(!stream_class->clock_class ||
			stream_class->clock_class == expected_clock_class);
		BT_CTF_OBJECT_MOVE_REF(stream_class->clock_class, expected_clock_class);
	}

	BT_LOGD("Added event class to stream class: "
		"stream-class-addr=%p, stream-class-name=\"%s\", "
		"stream-class-id=%" PRId64 ", event-class-addr=%p, "
		"event-class-name=\"%s\", event-class-id=%" PRId64,
		stream_class, bt_ctf_stream_class_common_get_name(stream_class),
		bt_ctf_stream_class_common_get_id(stream_class),
		event_class,
		bt_ctf_event_class_common_get_name(event_class),
		bt_ctf_event_class_common_get_id(event_class));

end:
	bt_ctf_validation_output_put_types(&validation_output);
	bt_ctf_object_put_ref(expected_clock_class);
	g_free(event_id);
	return ret;
}

static
int64_t get_event_class_count(void *element)
{
	return bt_ctf_stream_class_get_event_class_count(
			(struct bt_ctf_stream_class *) element);
}

static
void *get_event_class(void *element, int i)
{
	return bt_ctf_stream_class_get_event_class_by_index(
			(struct bt_ctf_stream_class *) element, i);
}

static
int visit_event_class(void *object, bt_ctf_visitor visitor,void *data)
{
	struct bt_ctf_visitor_object obj = {
		.object = object,
		.type = BT_CTF_VISITOR_OBJECT_TYPE_EVENT_CLASS
	};

	return visitor(&obj, data);
}

BT_HIDDEN
int bt_ctf_stream_class_common_visit(struct bt_ctf_stream_class_common *stream_class,
		bt_ctf_visitor visitor, void *data)
{
	int ret;
	struct bt_ctf_visitor_object obj = {
		.object = stream_class,
		.type = BT_CTF_VISITOR_OBJECT_TYPE_STREAM_CLASS
	};

	if (!stream_class || !visitor) {
		BT_LOGW("Invalid parameter: stream class or visitor is NULL: "
			"stream-class-addr=%p, visitor=%p",
			stream_class, visitor);
		ret = -1;
		goto end;
	}

	ret = bt_ctf_visitor_helper(&obj, get_event_class_count,
			get_event_class,
			visit_event_class, visitor, data);
	BT_LOGT("bt_ctf_visitor_helper() returned: ret=%d", ret);

end:
	return ret;
}

BT_HIDDEN
int bt_ctf_stream_class_visit(struct bt_ctf_stream_class *stream_class,
		bt_ctf_visitor visitor, void *data)
{
	return bt_ctf_stream_class_common_visit(BT_CTF_FROM_COMMON(stream_class),
		visitor, data);
}

BT_HIDDEN
void bt_ctf_stream_class_common_freeze(struct bt_ctf_stream_class_common *stream_class)
{
	if (!stream_class || stream_class->frozen) {
		return;
	}

	BT_LOGD("Freezing stream class: addr=%p, name=\"%s\", id=%" PRId64,
		stream_class, bt_ctf_stream_class_common_get_name(stream_class),
		bt_ctf_stream_class_common_get_id(stream_class));
	stream_class->frozen = 1;
	bt_ctf_field_type_common_freeze(stream_class->event_header_field_type);
	bt_ctf_field_type_common_freeze(stream_class->packet_context_field_type);
	bt_ctf_field_type_common_freeze(stream_class->event_context_field_type);
	bt_ctf_clock_class_freeze(stream_class->clock_class);
}

BT_HIDDEN
int bt_ctf_stream_class_common_validate_single_clock_class(
		struct bt_ctf_stream_class_common *stream_class,
		struct bt_ctf_clock_class **expected_clock_class)
{
	int ret;
	uint64_t i;

	BT_ASSERT(stream_class);
	BT_ASSERT(expected_clock_class);
	ret = bt_ctf_field_type_common_validate_single_clock_class(
		stream_class->packet_context_field_type,
		expected_clock_class);
	if (ret) {
		BT_LOGW("Stream class's packet context field type "
			"is not recursively mapped to the "
			"expected clock class: "
			"stream-class-addr=%p, "
			"stream-class-name=\"%s\", "
			"stream-class-id=%" PRId64 ", "
			"ft-addr=%p",
			stream_class,
			bt_ctf_stream_class_common_get_name(stream_class),
			stream_class->id,
			stream_class->packet_context_field_type);
		goto end;
	}

	ret = bt_ctf_field_type_common_validate_single_clock_class(
		stream_class->event_header_field_type,
		expected_clock_class);
	if (ret) {
		BT_LOGW("Stream class's event header field type "
			"is not recursively mapped to the "
			"expected clock class: "
			"stream-class-addr=%p, "
			"stream-class-name=\"%s\", "
			"stream-class-id=%" PRId64 ", "
			"ft-addr=%p",
			stream_class,
			bt_ctf_stream_class_common_get_name(stream_class),
			stream_class->id,
			stream_class->event_header_field_type);
		goto end;
	}

	ret = bt_ctf_field_type_common_validate_single_clock_class(
		stream_class->event_context_field_type,
		expected_clock_class);
	if (ret) {
		BT_LOGW("Stream class's event context field type "
			"is not recursively mapped to the "
			"expected clock class: "
			"stream-class-addr=%p, "
			"stream-class-name=\"%s\", "
			"stream-class-id=%" PRId64 ", "
			"ft-addr=%p",
			stream_class,
			bt_ctf_stream_class_common_get_name(stream_class),
			stream_class->id,
			stream_class->event_context_field_type);
		goto end;
	}

	for (i = 0; i < stream_class->event_classes->len; i++) {
		struct bt_ctf_event_class_common *event_class =
			g_ptr_array_index(stream_class->event_classes, i);

		BT_ASSERT(event_class);
		ret = bt_ctf_event_class_common_validate_single_clock_class(
			event_class, expected_clock_class);
		if (ret) {
			BT_LOGW("Stream class's event class contains a "
				"field type which is not recursively mapped to "
				"the expected clock class: "
				"stream-class-addr=%p, "
				"stream-class-name=\"%s\", "
				"stream-class-id=%" PRId64,
				stream_class,
				bt_ctf_stream_class_common_get_name(stream_class),
				stream_class->id);
			goto end;
		}
	}

end:
	return ret;
}

static
int init_event_header(struct bt_ctf_stream_class *stream_class)
{
	int ret = 0;
	struct bt_ctf_field_type *event_header_type =
		bt_ctf_field_type_structure_create();
	struct bt_ctf_field_type *_uint32_t =
		get_field_type(FIELD_TYPE_ALIAS_UINT32_T);
	struct bt_ctf_field_type *_uint64_t =
		get_field_type(FIELD_TYPE_ALIAS_UINT64_T);

	if (!event_header_type) {
		BT_LOGE_STR("Cannot create empty structure field type.");
		ret = -1;
		goto end;
	}

	ret = bt_ctf_field_type_structure_add_field(event_header_type,
		_uint32_t, "id");
	if (ret) {
		BT_LOGE_STR("Cannot add `id` field to event header field type.");
		goto end;
	}

	ret = bt_ctf_field_type_structure_add_field(event_header_type,
		_uint64_t, "timestamp");
	if (ret) {
		BT_LOGE_STR("Cannot add `timestamp` field to event header field type.");
		goto end;
	}

	bt_ctf_object_put_ref(stream_class->common.event_header_field_type);
	stream_class->common.event_header_field_type =
		(void *) event_header_type;
	event_header_type = NULL;

end:
	if (ret) {
		bt_ctf_object_put_ref(event_header_type);
	}

	bt_ctf_object_put_ref(_uint32_t);
	bt_ctf_object_put_ref(_uint64_t);
	return ret;
}

static
int init_packet_context(struct bt_ctf_stream_class *stream_class)
{
	int ret = 0;
	struct bt_ctf_field_type *packet_context_type =
		bt_ctf_field_type_structure_create();
	struct bt_ctf_field_type *_uint64_t =
		get_field_type(FIELD_TYPE_ALIAS_UINT64_T);
	struct bt_ctf_field_type *ts_begin_end_uint64_t;

	if (!packet_context_type) {
		BT_LOGE_STR("Cannot create empty structure field type.");
		ret = -1;
		goto end;
	}

	ts_begin_end_uint64_t = bt_ctf_field_type_copy(_uint64_t);
	if (!ts_begin_end_uint64_t) {
		BT_LOGE_STR("Cannot copy integer field type for `timestamp_begin` and `timestamp_end` fields.");
		ret = -1;
		goto end;
	}

	/*
	 * We create a stream packet context as proposed in the CTF
	 * specification.
	 */
	ret = bt_ctf_field_type_structure_add_field(packet_context_type,
		ts_begin_end_uint64_t, "timestamp_begin");
	if (ret) {
		BT_LOGE_STR("Cannot add `timestamp_begin` field to event header field type.");
		goto end;
	}

	ret = bt_ctf_field_type_structure_add_field(packet_context_type,
		ts_begin_end_uint64_t, "timestamp_end");
	if (ret) {
		BT_LOGE_STR("Cannot add `timestamp_end` field to event header field type.");
		goto end;
	}

	ret = bt_ctf_field_type_structure_add_field(packet_context_type,
		_uint64_t, "content_size");
	if (ret) {
		BT_LOGE_STR("Cannot add `content_size` field to event header field type.");
		goto end;
	}

	ret = bt_ctf_field_type_structure_add_field(packet_context_type,
		_uint64_t, "packet_size");
	if (ret) {
		BT_LOGE_STR("Cannot add `packet_size` field to event header field type.");
		goto end;
	}

	ret = bt_ctf_field_type_structure_add_field(packet_context_type,
		_uint64_t, "events_discarded");
	if (ret) {
		BT_LOGE_STR("Cannot add `events_discarded` field to event header field type.");
		goto end;
	}

	bt_ctf_object_put_ref(stream_class->common.packet_context_field_type);
	stream_class->common.packet_context_field_type =
		(void *) packet_context_type;
	packet_context_type = NULL;

end:
	if (ret) {
		bt_ctf_object_put_ref(packet_context_type);
		goto end;
	}

	bt_ctf_object_put_ref(_uint64_t);
	bt_ctf_object_put_ref(ts_begin_end_uint64_t);
	return ret;
}

static
void bt_ctf_stream_class_destroy(struct bt_ctf_object *obj)
{
	struct bt_ctf_stream_class *stream_class;

	stream_class = (void *) obj;
	BT_LOGD("Destroying CTF writer stream class: addr=%p, name=\"%s\", id=%" PRId64,
		stream_class, bt_ctf_stream_class_get_name(stream_class),
		bt_ctf_stream_class_get_id(stream_class));
	bt_ctf_stream_class_common_finalize(BT_CTF_TO_COMMON(stream_class));
	bt_ctf_object_put_ref(stream_class->clock);
	g_free(stream_class);
}

struct bt_ctf_stream_class *bt_ctf_stream_class_create(const char *name)
{
	struct bt_ctf_stream_class *stream_class;
	int ret;

	BT_LOGD("Creating CTF writer stream class object: name=\"%s\"", name);
	stream_class = g_new0(struct bt_ctf_stream_class, 1);
	if (!stream_class) {
		BT_LOGE_STR("Failed to allocate one CTF writer stream class.");
		goto error;
	}

	ret = bt_ctf_stream_class_common_initialize(BT_CTF_TO_COMMON(stream_class),
		name, bt_ctf_stream_class_destroy);
	if (ret) {
		/* bt_ctf_stream_class_common_initialize() logs errors */
		goto error;
	}

	ret = init_event_header(stream_class);
	if (ret) {
		BT_LOGE_STR("Cannot initialize stream class's event header field type.");
		goto error;
	}

	ret = init_packet_context(stream_class);
	if (ret) {
		BT_LOGE_STR("Cannot initialize stream class's packet context field type.");
		goto error;
	}

	BT_LOGD("Created CTF writer stream class object: addr=%p, name=\"%s\"",
		stream_class, name);
	return stream_class;

error:
	BT_CTF_OBJECT_PUT_REF_AND_RESET(stream_class);
	return stream_class;
}

static
int try_map_clock_class(struct bt_ctf_stream_class *stream_class,
		struct bt_ctf_field_type *parent_ft, const char *field_name)
{
	struct bt_ctf_clock_class *mapped_clock_class = NULL;
	int ret = 0;
	struct bt_ctf_field_type *ft =
		bt_ctf_field_type_structure_get_field_type_by_name(parent_ft,
			field_name);

	BT_ASSERT(stream_class->clock);

	if (!ft) {
		/* Field does not exist: not an error */
		goto end;
	}

	BT_ASSERT(((struct bt_ctf_field_type_common *) ft)->id ==
		BT_CTF_FIELD_TYPE_ID_INTEGER);
	mapped_clock_class =
		bt_ctf_field_type_integer_get_mapped_clock_class(ft);
	if (!mapped_clock_class) {
		struct bt_ctf_field_type *ft_copy;

		if (!stream_class->clock) {
			BT_LOGW("Cannot automatically set field's type mapped clock class: stream class's clock is not set: "
				"stream-class-addr=%p, stream-class-name=\"%s\", "
				"stream-class-id=%" PRId64 ", ft-addr=%p",
				stream_class,
				bt_ctf_stream_class_get_name(stream_class),
				bt_ctf_stream_class_get_id(stream_class), ft);
			ret = -1;
			goto end;
		}

		ft_copy = bt_ctf_field_type_copy(ft);
		if (!ft_copy) {
			BT_LOGE("Failed to copy integer field type: ft-addr=%p",
				ft);
		}

		ret = bt_ctf_field_type_common_integer_set_mapped_clock_class_no_check_frozen(
			(void *) ft_copy, stream_class->clock->clock_class);
		BT_ASSERT(ret == 0);

		ret = bt_ctf_field_type_common_structure_replace_field(
			(void *) parent_ft, field_name, (void *) ft_copy);
		bt_ctf_object_put_ref(ft_copy);
		BT_LOGT("Automatically mapped field type to stream class's clock class: "
			"stream-class-addr=%p, stream-class-name=\"%s\", "
			"stream-class-id=%" PRId64 ", ft-addr=%p, "
			"ft-copy-addr=%p",
			stream_class,
			bt_ctf_stream_class_get_name(stream_class),
			bt_ctf_stream_class_get_id(stream_class), ft, ft_copy);
	}

end:
	bt_ctf_object_put_ref(ft);
	bt_ctf_object_put_ref(mapped_clock_class);
	return ret;
}

BT_HIDDEN
int bt_ctf_stream_class_map_clock_class(
		struct bt_ctf_stream_class *stream_class,
		struct bt_ctf_field_type *packet_context_type,
		struct bt_ctf_field_type *event_header_type)
{
	int ret = 0;

	BT_ASSERT(stream_class);

	if (!stream_class->clock) {
		/* No clock class to map to */
		goto end;
	}

	if (packet_context_type) {
		if (try_map_clock_class(stream_class, packet_context_type,
				"timestamp_begin")) {
			BT_LOGE_STR("Cannot automatically set stream class's packet context field type's `timestamp_begin` field's mapped clock class.");
			ret = -1;
			goto end;
		}

		if (try_map_clock_class(stream_class, packet_context_type,
				"timestamp_end")) {
			BT_LOGE_STR("Cannot automatically set stream class's packet context field type's `timestamp_end` field's mapped clock class.");
			ret = -1;
			goto end;
		}
	}

	if (event_header_type) {
		if (try_map_clock_class(stream_class, event_header_type,
				"timestamp")) {
			BT_LOGE_STR("Cannot automatically set stream class's event header field type's `timestamp` field's mapped clock class.");
			ret = -1;
			goto end;
		}
	}

end:
	return ret;
}

struct bt_ctf_clock *bt_ctf_stream_class_get_clock(
		struct bt_ctf_stream_class *stream_class)
{
	struct bt_ctf_clock *clock = NULL;

	if (!stream_class) {
		BT_LOGW_STR("Invalid parameter: stream class is NULL.");
		goto end;
	}

	if (!stream_class->clock) {
		BT_LOGT("Stream class has no clock: "
			"addr=%p, name=\"%s\", id=%" PRId64,
			stream_class,
			bt_ctf_stream_class_get_name(stream_class),
			bt_ctf_stream_class_get_id(stream_class));
		goto end;
	}

	clock = bt_ctf_object_get_ref(stream_class->clock);

end:
	return clock;
}

int bt_ctf_stream_class_set_clock(
		struct bt_ctf_stream_class *stream_class,
		struct bt_ctf_clock *clock)
{
	int ret = 0;

	if (!stream_class || !clock) {
		BT_LOGW("Invalid parameter: stream class or clock is NULL: "
			"stream-class-addr=%p, clock-addr=%p",
			stream_class, clock);
		ret = -1;
		goto end;
	}

	if (stream_class->common.frozen) {
		BT_LOGW("Invalid parameter: stream class is frozen: "
			"addr=%p, name=\"%s\", id=%" PRId64,
			stream_class,
			bt_ctf_stream_class_get_name(stream_class),
			bt_ctf_stream_class_get_id(stream_class));
		ret = -1;
		goto end;
	}

	/* Replace the current clock of this stream class. */
	bt_ctf_object_put_ref(stream_class->clock);
	stream_class->clock = bt_ctf_object_get_ref(clock);
	BT_LOGT("Set stream class's clock: "
		"addr=%p, name=\"%s\", id=%" PRId64 ", "
		"clock-addr=%p, clock-name=\"%s\"",
		stream_class,
		bt_ctf_stream_class_get_name(stream_class),
		bt_ctf_stream_class_get_id(stream_class),
		stream_class->clock,
		bt_ctf_clock_get_name(stream_class->clock));

end:
	return ret;
}

BT_HIDDEN
int bt_ctf_stream_class_serialize(struct bt_ctf_stream_class *stream_class,
		struct metadata_context *context)
{
	int ret = 0;
	size_t i;
	struct bt_ctf_trace *trace;
	struct bt_ctf_field_type *packet_header_type = NULL;

	BT_LOGD("Serializing stream class's metadata: "
		"stream-class-addr=%p, stream-class-name=\"%s\", "
		"stream-class-id=%" PRId64 ", metadata-context-addr=%p",
		stream_class,
		bt_ctf_stream_class_get_name(stream_class),
		bt_ctf_stream_class_get_id(stream_class), context);
	g_string_assign(context->field_name, "");
	context->current_indentation_level = 1;
	if (!stream_class->common.id_set) {
		BT_LOGW_STR("Stream class's ID is not set.");
		ret = -1;
		goto end;
	}

	g_string_append(context->string, "stream {\n");

	/*
	 * The reference to the trace is only borrowed since the
	 * serialization of the stream class might have been triggered
	 * by the trace's destruction. In such a case, the trace's
	 * reference count would, unexepectedly, go through the sequence
	 * 1 -> 0 -> 1 -> 0 -> ..., provoking an endless loop of destruction
	 * and serialization.
	 */
	trace = BT_CTF_FROM_COMMON(bt_ctf_stream_class_common_borrow_trace(
		BT_CTF_TO_COMMON(stream_class)));
	BT_ASSERT(trace);
	packet_header_type = bt_ctf_trace_get_packet_header_field_type(trace);
	trace = NULL;
	if (packet_header_type) {
		struct bt_ctf_field_type *stream_id_type;

		stream_id_type =
			bt_ctf_field_type_structure_get_field_type_by_name(
				packet_header_type, "stream_id");
		if (stream_id_type) {
			/*
			 * Only set the stream's id if the trace's packet header
			 * contains a stream_id field. This field is only
			 * needed if the trace contains only one stream
			 * class.
			 */
			g_string_append_printf(context->string,
				"\tid = %" PRId64 ";\n",
				stream_class->common.id);
		}
		bt_ctf_object_put_ref(stream_id_type);
	}
	if (stream_class->common.event_header_field_type) {
		BT_LOGD_STR("Serializing stream class's event header field type's metadata.");
		g_string_append(context->string, "\tevent.header := ");
		ret = bt_ctf_field_type_serialize_recursive(
			(void *) stream_class->common.event_header_field_type,
			context);
		if (ret) {
			BT_LOGW("Cannot serialize stream class's event header field type's metadata: "
				"ret=%d", ret);
			goto end;
		}
		g_string_append(context->string, ";");
	}


	if (stream_class->common.packet_context_field_type) {
		BT_LOGD_STR("Serializing stream class's packet context field type's metadata.");
		g_string_append(context->string, "\n\n\tpacket.context := ");
		ret = bt_ctf_field_type_serialize_recursive(
			(void *) stream_class->common.packet_context_field_type,
			context);
		if (ret) {
			BT_LOGW("Cannot serialize stream class's packet context field type's metadata: "
				"ret=%d", ret);
			goto end;
		}
		g_string_append(context->string, ";");
	}

	if (stream_class->common.event_context_field_type) {
		BT_LOGD_STR("Serializing stream class's event context field type's metadata.");
		g_string_append(context->string, "\n\n\tevent.context := ");
		ret = bt_ctf_field_type_serialize_recursive(
			(void *) stream_class->common.event_context_field_type,
			context);
		if (ret) {
			BT_LOGW("Cannot serialize stream class's event context field type's metadata: "
				"ret=%d", ret);
			goto end;
		}
		g_string_append(context->string, ";");
	}

	g_string_append(context->string, "\n};\n\n");

	for (i = 0; i < stream_class->common.event_classes->len; i++) {
		struct bt_ctf_event_class *event_class =
			stream_class->common.event_classes->pdata[i];

		ret = bt_ctf_event_class_serialize(event_class, context);
		if (ret) {
			BT_LOGW("Cannot serialize event class's metadata: "
				"event-class-addr=%p, event-class-name=\"%s\", "
				"event-class-id=%" PRId64,
				event_class,
				bt_ctf_event_class_get_name(event_class),
				bt_ctf_event_class_get_id(event_class));
			goto end;
		}
	}

end:
	bt_ctf_object_put_ref(packet_header_type);
	context->current_indentation_level = 0;
	return ret;
}

struct bt_ctf_trace *bt_ctf_stream_class_get_trace(
		struct bt_ctf_stream_class *stream_class)
{
	return bt_ctf_object_get_ref(bt_ctf_stream_class_common_borrow_trace(
		BT_CTF_TO_COMMON(stream_class)));
}

const char *bt_ctf_stream_class_get_name(
		struct bt_ctf_stream_class *stream_class)
{
	return bt_ctf_stream_class_common_get_name(BT_CTF_TO_COMMON(stream_class));
}

int bt_ctf_stream_class_set_name(
		struct bt_ctf_stream_class *stream_class, const char *name)
{
	return bt_ctf_stream_class_common_set_name(BT_CTF_TO_COMMON(stream_class),
		name);
}

int64_t bt_ctf_stream_class_get_id(
		struct bt_ctf_stream_class *stream_class)
{
	return bt_ctf_stream_class_common_get_id(BT_CTF_TO_COMMON(stream_class));
}

int bt_ctf_stream_class_set_id(
		struct bt_ctf_stream_class *stream_class, uint64_t id)
{
	return bt_ctf_stream_class_common_set_id(BT_CTF_TO_COMMON(stream_class), id);
}

struct bt_ctf_field_type *bt_ctf_stream_class_get_packet_context_type(
		struct bt_ctf_stream_class *stream_class)
{
	return bt_ctf_object_get_ref(
		bt_ctf_stream_class_common_borrow_packet_context_field_type(
			BT_CTF_TO_COMMON(stream_class)));
}

int bt_ctf_stream_class_set_packet_context_type(
		struct bt_ctf_stream_class *stream_class,
		struct bt_ctf_field_type *packet_context_type)
{
	return bt_ctf_stream_class_common_set_packet_context_field_type(
		BT_CTF_TO_COMMON(stream_class), (void *) packet_context_type);
}

struct bt_ctf_field_type *
bt_ctf_stream_class_get_event_header_type(
		struct bt_ctf_stream_class *stream_class)
{
	return bt_ctf_object_get_ref(
		bt_ctf_stream_class_common_borrow_event_header_field_type(
			BT_CTF_TO_COMMON(stream_class)));
}

int bt_ctf_stream_class_set_event_header_type(
		struct bt_ctf_stream_class *stream_class,
		struct bt_ctf_field_type *event_header_type)
{
	return bt_ctf_stream_class_common_set_event_header_field_type(
		BT_CTF_TO_COMMON(stream_class), (void *) event_header_type);
}

struct bt_ctf_field_type *
bt_ctf_stream_class_get_event_context_type(
		struct bt_ctf_stream_class *stream_class)
{
	return bt_ctf_object_get_ref(
		bt_ctf_stream_class_common_borrow_event_context_field_type(
			BT_CTF_TO_COMMON(stream_class)));
}

int bt_ctf_stream_class_set_event_context_type(
		struct bt_ctf_stream_class *stream_class,
		struct bt_ctf_field_type *event_context_type)
{
	return bt_ctf_stream_class_common_set_event_context_field_type(
		BT_CTF_TO_COMMON(stream_class), (void *) event_context_type);
}

int64_t bt_ctf_stream_class_get_event_class_count(
		struct bt_ctf_stream_class *stream_class)
{
	return bt_ctf_stream_class_common_get_event_class_count(
		BT_CTF_TO_COMMON(stream_class));
}

struct bt_ctf_event_class *bt_ctf_stream_class_get_event_class_by_index(
		struct bt_ctf_stream_class *stream_class, uint64_t index)
{
	return bt_ctf_object_get_ref(
		bt_ctf_stream_class_common_borrow_event_class_by_index(
			BT_CTF_TO_COMMON(stream_class), index));
}

struct bt_ctf_event_class *bt_ctf_stream_class_get_event_class_by_id(
		struct bt_ctf_stream_class *stream_class, uint64_t id)
{
	return bt_ctf_object_get_ref(
		bt_ctf_stream_class_common_borrow_event_class_by_id(
			BT_CTF_TO_COMMON(stream_class), id));
}

int bt_ctf_stream_class_add_event_class(
		struct bt_ctf_stream_class *stream_class,
		struct bt_ctf_event_class *event_class)
{
	return bt_ctf_stream_class_common_add_event_class(
		BT_CTF_TO_COMMON(stream_class), BT_CTF_TO_COMMON(event_class),
		(bt_ctf_validation_flag_copy_field_type_func) bt_ctf_field_type_copy);
}