[babeltrace.git] / src / plugins / ctf / lttng-live / metadata.c

/*
 * Copyright 2019 - Francis Deslauriers <francis.deslauriers@efficios.com>
 * Copyright 2016 - Philippe Proulx <pproulx@efficios.com>
 * Copyright 2010-2011 - EfficiOS Inc. and Linux Foundation
 *
 * Some functions are based on older functions written by Mathieu Desnoyers.
 *
 * 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_COMP_LOG_SELF_COMP self_comp
#define BT_LOG_OUTPUT_LEVEL log_level
#define BT_LOG_TAG "PLUGIN/SRC.CTF.LTTNG-LIVE/META"
#include "logging/comp-logging.h"

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdbool.h>
#include <glib.h>
#include "compat/memstream.h"
#include <babeltrace2/babeltrace.h>

#include "metadata.h"
#include "../common/metadata/decoder.h"
#include "../common/metadata/ctf-meta-configure-ir-trace.h"

#define TSDL_MAGIC	0x75d11d57

struct packet_header {
	uint32_t magic;
	uint8_t  uuid[16];
	uint32_t checksum;
	uint32_t content_size;
	uint32_t packet_size;
	uint8_t  compression_scheme;
	uint8_t  encryption_scheme;
	uint8_t  checksum_scheme;
	uint8_t  major;
	uint8_t  minor;
} __attribute__((__packed__));


static
bool stream_classes_all_have_default_clock_class(bt_trace_class *tc,
		bt_logging_level log_level,
		bt_self_component *self_comp)
{
	uint64_t i, sc_count;
	const bt_clock_class *cc = NULL;
	const bt_stream_class *sc;
	bool ret = true;

	sc_count = bt_trace_class_get_stream_class_count(tc);
	for (i = 0; i < sc_count; i++) {
		sc = bt_trace_class_borrow_stream_class_by_index_const(tc, i);

		BT_ASSERT(sc);

		cc = bt_stream_class_borrow_default_clock_class_const(sc);
		if (!cc) {
			ret = false;
			BT_COMP_LOGE("Stream class doesn't have a default clock class: "
				"sc-id=%" PRIu64 ", sc-name=\"%s\"",
				bt_stream_class_get_id(sc),
				bt_stream_class_get_name(sc));
			goto end;
		}
	}

end:
	return ret;
}
/*
 * Iterate over the stream classes and returns the first clock class
 * encountered. This is useful to create message iterator inactivity message as
 * we don't need a particular clock class.
 */
static
const bt_clock_class *borrow_any_clock_class(bt_trace_class *tc)
{
	uint64_t i, sc_count;
	const bt_clock_class *cc = NULL;
	const bt_stream_class *sc;

	sc_count = bt_trace_class_get_stream_class_count(tc);
	for (i = 0; i < sc_count; i++) {
		sc = bt_trace_class_borrow_stream_class_by_index_const(tc, i);
		BT_ASSERT_DBG(sc);

		cc = bt_stream_class_borrow_default_clock_class_const(sc);
		if (cc) {
			goto end;
		}
	}
end:
	BT_ASSERT_DBG(cc);
	return cc;
}

BT_HIDDEN
enum lttng_live_iterator_status lttng_live_metadata_update(
		struct lttng_live_trace *trace)
{
	struct lttng_live_session *session = trace->session;
	struct lttng_live_metadata *metadata = trace->metadata;
	size_t size, len_read = 0;
	char *metadata_buf = NULL;
	bool keep_receiving;
	FILE *fp = NULL;
	enum ctf_metadata_decoder_status decoder_status;
	enum lttng_live_iterator_status status =
		LTTNG_LIVE_ITERATOR_STATUS_OK;
	bt_logging_level log_level = trace->log_level;
	bt_self_component *self_comp = trace->self_comp;
	enum lttng_live_get_one_metadata_status metadata_status;

	/* No metadata stream yet. */
	if (!metadata) {
		if (session->new_streams_needed) {
			status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
		} else {
			session->new_streams_needed = true;
			status = LTTNG_LIVE_ITERATOR_STATUS_CONTINUE;
		}
		goto end;
	}

	if (!metadata->trace) {
		trace->new_metadata_needed = false;
	}

	if (!trace->new_metadata_needed) {
		goto end;
	}

	/* Open for writing */
	fp = bt_open_memstream(&metadata_buf, &size);
	if (!fp) {
		BT_COMP_LOGE("Metadata open_memstream: %s", strerror(errno));
		goto error;
	}

	keep_receiving = true;
	/* Grab all available metadata. */
	while (keep_receiving) {
		size_t reply_len = 0;
		/*
		 * lttng_live_get_one_metadata_packet() asks the Relay Daemon
		 * for new metadata. If new metadata is received, the function
		 * writes it to the provided file handle and updates the
		 * reply_len output parameter. We call this function in loop
		 * until it returns _END meaning that no new metadata is
		 * available.
		 * We may receive a _CLOSED status if the metadata stream we
		 * are requesting is no longer available on the relay.
		 * If we receive an _ERROR status, it means there was a
		 * networking, allocating, or some other unrecoverable error.
		 */
		metadata_status = lttng_live_get_one_metadata_packet(trace, fp,
			&reply_len);

		switch (metadata_status) {
		case LTTNG_LIVE_GET_ONE_METADATA_STATUS_OK:
			len_read += reply_len;
			break;
		case LTTNG_LIVE_GET_ONE_METADATA_STATUS_END:
			keep_receiving = false;
			break;
		case LTTNG_LIVE_GET_ONE_METADATA_STATUS_CLOSED:
			keep_receiving = false;
			break;
		case LTTNG_LIVE_GET_ONE_METADATA_STATUS_ERROR:
			goto error;
		default:
			abort();
		}
	}

	/*
	 * A closed metadata stream means the trace is no longer active. Return
	 * _END so that the caller can remove the trace from its list.
	 */
	if (metadata_status == LTTNG_LIVE_GET_ONE_METADATA_STATUS_CLOSED) {
		status = LTTNG_LIVE_ITERATOR_STATUS_END;
		goto end;
	}

	if (bt_close_memstream(&metadata_buf, &size, fp)) {
		BT_COMP_LOGE("bt_close_memstream: %s", strerror(errno));
	}

	fp = NULL;

	if (len_read == 0) {
		if (!trace->trace) {
			status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
			goto end;
		}
		trace->new_metadata_needed = false;
		goto end;
	}

	fp = bt_fmemopen(metadata_buf, len_read, "rb");
	if (!fp) {
		BT_COMP_LOGE("Cannot memory-open metadata buffer: %s",
			strerror(errno));
		goto error;
	}

	/*
	 * The call to ctf_metadata_decoder_append_content() will append
	 * new metadata to our current trace class.
	 */
	decoder_status = ctf_metadata_decoder_append_content(
		metadata->decoder, fp);
	switch (decoder_status) {
	case CTF_METADATA_DECODER_STATUS_OK:
		if (!trace->trace_class) {
			struct ctf_trace_class *tc =
				ctf_metadata_decoder_borrow_ctf_trace_class(
					metadata->decoder);

			trace->trace_class =
				ctf_metadata_decoder_get_ir_trace_class(
						metadata->decoder);
			trace->trace = bt_trace_create(trace->trace_class);
			if (!trace->trace) {
				goto error;
			}
			if (ctf_trace_class_configure_ir_trace(tc,
					trace->trace)) {
				goto error;
			}
			if (!stream_classes_all_have_default_clock_class(
					trace->trace_class, log_level,
					self_comp)) {
				/* Error logged in function. */
				goto error;
			}
			trace->clock_class =
				borrow_any_clock_class(trace->trace_class);
		}
		trace->new_metadata_needed = false;

		break;
	case CTF_METADATA_DECODER_STATUS_INCOMPLETE:
		status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
		break;
	default:
		goto error;
	}

	goto end;

error:
	if (errno == EINTR) {
		if (lttng_live_graph_is_canceled(session->lttng_live_msg_iter)) {
			status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
		}
	} else {
		status = LTTNG_LIVE_ITERATOR_STATUS_ERROR;
	}
end:
	if (fp) {
		int closeret;

		closeret = fclose(fp);
		if (closeret) {
			BT_COMP_LOGE("Error on fclose");
		}
	}
	free(metadata_buf);
	return status;
}

BT_HIDDEN
int lttng_live_metadata_create_stream(struct lttng_live_session *session,
		uint64_t ctf_trace_id, uint64_t stream_id,
		const char *trace_name)
{
	struct lttng_live_metadata *metadata = NULL;
	struct lttng_live_trace *trace;
	struct ctf_metadata_decoder_config cfg = {
		.log_level = session->log_level,
		.self_comp = session->self_comp,
		.clock_class_offset_s = 0,
		.clock_class_offset_ns = 0,
		.create_trace_class = true,
	};

	metadata = g_new0(struct lttng_live_metadata, 1);
	if (!metadata) {
		return -1;
	}
	metadata->log_level = session->log_level;
	metadata->self_comp = session->self_comp;
	metadata->stream_id = stream_id;

	metadata->decoder = ctf_metadata_decoder_create(&cfg);
	if (!metadata->decoder) {
		goto error;
	}
	trace = lttng_live_borrow_trace(session, ctf_trace_id);
	if (!trace) {
		goto error;
	}
	metadata->trace = trace;
	trace->metadata = metadata;
	return 0;

error:
	ctf_metadata_decoder_destroy(metadata->decoder);
	g_free(metadata);
	return -1;
}

BT_HIDDEN
void lttng_live_metadata_fini(struct lttng_live_trace *trace)
{
	struct lttng_live_metadata *metadata = trace->metadata;

	if (!metadata) {
		return;
	}
	ctf_metadata_decoder_destroy(metadata->decoder);
	trace->metadata = NULL;
	g_free(metadata);
}
Commit	Line	Data
7cdc2bab	1	/*
bb18709b	2	* Copyright 2019 - Francis Deslauriers <francis.deslauriers@efficios.com>
7cdc2bab MD	3	* Copyright 2016 - Philippe Proulx <pproulx@efficios.com>
	4	* Copyright 2010-2011 - EfficiOS Inc. and Linux Foundation
	5	*
	6	* Some functions are based on older functions written by Mathieu Desnoyers.
	7	*
	8	* Permission is hereby granted, free of charge, to any person obtaining a copy
	9	* of this software and associated documentation files (the "Software"), to deal
	10	* in the Software without restriction, including without limitation the rights
	11	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	12	* copies of the Software, and to permit persons to whom the Software is
	13	* furnished to do so, subject to the following conditions:
	14	*
	15	* The above copyright notice and this permission notice shall be included in
	16	* all copies or substantial portions of the Software.
	17	*
	18	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	19	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	20	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	21	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	22	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	23	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	24	* SOFTWARE.
	25	*/
	26
5278d5ba	27	#define BT_COMP_LOG_SELF_COMP self_comp
1c0ceb65	28	#define BT_LOG_OUTPUT_LEVEL log_level
b03487ab	29	#define BT_LOG_TAG "PLUGIN/SRC.CTF.LTTNG-LIVE/META"
3fa1b6a3	30	#include "logging/comp-logging.h"
020bc26f	31
7cdc2bab MD	32	#include <stdio.h>
	33	#include <stdint.h>
	34	#include <stdlib.h>
	35	#include <stdbool.h>
	36	#include <glib.h>
57952005	37	#include "compat/memstream.h"
71c5da58	38	#include <babeltrace2/babeltrace.h>
7cdc2bab	39
7cdc2bab MD	40	#include "metadata.h"
7cdc2bab MD	41	#include "../common/metadata/decoder.h"
cd03c43c	42	#include "../common/metadata/ctf-meta-configure-ir-trace.h"
7cdc2bab MD	43
	44	#define TSDL_MAGIC 0x75d11d57
	45
	46	struct packet_header {
	47	uint32_t magic;
	48	uint8_t uuid[16];
	49	uint32_t checksum;
	50	uint32_t content_size;
	51	uint32_t packet_size;
	52	uint8_t compression_scheme;
	53	uint8_t encryption_scheme;
	54	uint8_t checksum_scheme;
	55	uint8_t major;
	56	uint8_t minor;
	57	} __attribute__((__packed__));
	58
bb18709b	59
7cdc2bab	60	static
1c0ceb65	61	bool stream_classes_all_have_default_clock_class(bt_trace_class *tc,
5278d5ba PP	62	bt_logging_level log_level,
5278d5ba PP	63	bt_self_component *self_comp)
7cdc2bab	64	{
bb18709b FD	65	uint64_t i, sc_count;
	66	const bt_clock_class *cc = NULL;
	67	const bt_stream_class *sc;
	68	bool ret = true;
7cdc2bab	69
bb18709b FD	70	sc_count = bt_trace_class_get_stream_class_count(tc);
	71	for (i = 0; i < sc_count; i++) {
	72	sc = bt_trace_class_borrow_stream_class_by_index_const(tc, i);
7cdc2bab	73
bb18709b	74	BT_ASSERT(sc);
7cdc2bab	75
bb18709b FD	76	cc = bt_stream_class_borrow_default_clock_class_const(sc);
	77	if (!cc) {
	78	ret = false;
5278d5ba	79	BT_COMP_LOGE("Stream class doesn't have a default clock class: "
bb18709b FD	80	"sc-id=%" PRIu64 ", sc-name=\"%s\"",
	81	bt_stream_class_get_id(sc),
	82	bt_stream_class_get_name(sc));
	83	goto end;
7cdc2bab MD	84	}
	85	}
	86
7cdc2bab	87	end:
bb18709b FD	88	return ret;
	89	}
	90	/*
	91	* Iterate over the stream classes and returns the first clock class
	92	* encountered. This is useful to create message iterator inactivity message as
	93	* we don't need a particular clock class.
	94	*/
	95	static
	96	const bt_clock_class borrow_any_clock_class(bt_trace_class tc)
	97	{
	98	uint64_t i, sc_count;
	99	const bt_clock_class *cc = NULL;
	100	const bt_stream_class *sc;
	101
	102	sc_count = bt_trace_class_get_stream_class_count(tc);
	103	for (i = 0; i < sc_count; i++) {
	104	sc = bt_trace_class_borrow_stream_class_by_index_const(tc, i);
ec4a3354	105	BT_ASSERT_DBG(sc);
bb18709b FD	106
	107	cc = bt_stream_class_borrow_default_clock_class_const(sc);
	108	if (cc) {
	109	goto end;
	110	}
	111	}
	112	end:
ec4a3354	113	BT_ASSERT_DBG(cc);
bb18709b	114	return cc;
7cdc2bab MD	115	}
	116
	117	BT_HIDDEN
bb18709b	118	enum lttng_live_iterator_status lttng_live_metadata_update(
7cdc2bab MD	119	struct lttng_live_trace *trace)
	120	{
	121	struct lttng_live_session *session = trace->session;
7cdc2bab	122	struct lttng_live_metadata *metadata = trace->metadata;
7cdc2bab MD	123	size_t size, len_read = 0;
7cdc2bab MD	124	char *metadata_buf = NULL;
f797424a	125	bool keep_receiving;
7cdc2bab MD	126	FILE *fp = NULL;
7cdc2bab MD	127	enum ctf_metadata_decoder_status decoder_status;
bb18709b FD	128	enum lttng_live_iterator_status status =
bb18709b FD	129	LTTNG_LIVE_ITERATOR_STATUS_OK;
1c0ceb65	130	bt_logging_level log_level = trace->log_level;
5278d5ba	131	bt_self_component *self_comp = trace->self_comp;
f797424a	132	enum lttng_live_get_one_metadata_status metadata_status;
7cdc2bab MD	133
	134	/* No metadata stream yet. */
	135	if (!metadata) {
	136	if (session->new_streams_needed) {
bb18709b	137	status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
7cdc2bab MD	138	} else {
7cdc2bab MD	139	session->new_streams_needed = true;
bb18709b	140	status = LTTNG_LIVE_ITERATOR_STATUS_CONTINUE;
7cdc2bab MD	141	}
	142	goto end;
	143	}
	144
6f79a7cf MD	145	if (!metadata->trace) {
	146	trace->new_metadata_needed = false;
	147	}
	148
7cdc2bab MD	149	if (!trace->new_metadata_needed) {
	150	goto end;
	151	}
	152
	153	/* Open for writing */
	154	fp = bt_open_memstream(&metadata_buf, &size);
	155	if (!fp) {
5278d5ba	156	BT_COMP_LOGE("Metadata open_memstream: %s", strerror(errno));
7cdc2bab MD	157	goto error;
	158	}
	159
f797424a	160	keep_receiving = true;
7cdc2bab	161	/* Grab all available metadata. */
f797424a FD	162	while (keep_receiving) {
f797424a FD	163	size_t reply_len = 0;
7cdc2bab	164	/*
f797424a FD	165	* lttng_live_get_one_metadata_packet() asks the Relay Daemon
	166	* for new metadata. If new metadata is received, the function
	167	* writes it to the provided file handle and updates the
	168	* reply_len output parameter. We call this function in loop
	169	* until it returns _END meaning that no new metadata is
	170	* available.
	171	* We may receive a _CLOSED status if the metadata stream we
	172	* are requesting is no longer available on the relay.
	173	* If we receive an _ERROR status, it means there was a
	174	* networking, allocating, or some other unrecoverable error.
7cdc2bab	175	*/
f797424a FD	176	metadata_status = lttng_live_get_one_metadata_packet(trace, fp,
	177	&reply_len);
	178
	179	switch (metadata_status) {
	180	case LTTNG_LIVE_GET_ONE_METADATA_STATUS_OK:
	181	len_read += reply_len;
	182	break;
	183	case LTTNG_LIVE_GET_ONE_METADATA_STATUS_END:
	184	keep_receiving = false;
	185	break;
	186	case LTTNG_LIVE_GET_ONE_METADATA_STATUS_CLOSED:
	187	keep_receiving = false;
	188	break;
	189	case LTTNG_LIVE_GET_ONE_METADATA_STATUS_ERROR:
	190	goto error;
	191	default:
	192	abort();
7cdc2bab	193	}
f797424a	194	}
7cdc2bab MD	195
7cdc2bab MD	196	/*
f797424a FD	197	* A closed metadata stream means the trace is no longer active. Return
f797424a FD	198	* _END so that the caller can remove the trace from its list.
7cdc2bab	199	*/
f797424a FD	200	if (metadata_status == LTTNG_LIVE_GET_ONE_METADATA_STATUS_CLOSED) {
	201	status = LTTNG_LIVE_ITERATOR_STATUS_END;
	202	goto end;
7cdc2bab MD	203	}
	204
	205	if (bt_close_memstream(&metadata_buf, &size, fp)) {
5278d5ba	206	BT_COMP_LOGE("bt_close_memstream: %s", strerror(errno));
7cdc2bab	207	}
67875d75	208
7cdc2bab MD	209	fp = NULL;
	210
	211	if (len_read == 0) {
	212	if (!trace->trace) {
bb18709b	213	status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
7cdc2bab MD	214	goto end;
	215	}
	216	trace->new_metadata_needed = false;
	217	goto end;
	218	}
	219
7cdc2bab MD	220	fp = bt_fmemopen(metadata_buf, len_read, "rb");
7cdc2bab MD	221	if (!fp) {
5278d5ba	222	BT_COMP_LOGE("Cannot memory-open metadata buffer: %s",
7cdc2bab MD	223	strerror(errno));
	224	goto error;
	225	}
	226
bb18709b	227	/*
526c3a49 PP	228	* The call to ctf_metadata_decoder_append_content() will append
526c3a49 PP	229	* new metadata to our current trace class.
bb18709b	230	*/
526c3a49 PP	231	decoder_status = ctf_metadata_decoder_append_content(
526c3a49 PP	232	metadata->decoder, fp);
7cdc2bab MD	233	switch (decoder_status) {
7cdc2bab MD	234	case CTF_METADATA_DECODER_STATUS_OK:
bb18709b	235	if (!trace->trace_class) {
cd03c43c PP	236	struct ctf_trace_class *tc =
	237	ctf_metadata_decoder_borrow_ctf_trace_class(
	238	metadata->decoder);
	239
bb18709b FD	240	trace->trace_class =
	241	ctf_metadata_decoder_get_ir_trace_class(
	242	metadata->decoder);
	243	trace->trace = bt_trace_create(trace->trace_class);
cd03c43c PP	244	if (!trace->trace) {
	245	goto error;
	246	}
	247	if (ctf_trace_class_configure_ir_trace(tc,
	248	trace->trace)) {
	249	goto error;
	250	}
bb18709b	251	if (!stream_classes_all_have_default_clock_class(
5278d5ba PP	252	trace->trace_class, log_level,
5278d5ba PP	253	self_comp)) {
bb18709b FD	254	/* Error logged in function. */
	255	goto error;
	256	}
	257	trace->clock_class =
	258	borrow_any_clock_class(trace->trace_class);
7cdc2bab	259	}
bb18709b FD	260	trace->new_metadata_needed = false;
bb18709b FD	261
7cdc2bab MD	262	break;
7cdc2bab MD	263	case CTF_METADATA_DECODER_STATUS_INCOMPLETE:
bb18709b	264	status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
7cdc2bab	265	break;
26aa224b	266	default:
7cdc2bab MD	267	goto error;
	268	}
	269
	270	goto end;
f797424a	271
7cdc2bab	272	error:
f797424a FD	273	if (errno == EINTR) {
	274	if (lttng_live_graph_is_canceled(session->lttng_live_msg_iter)) {
	275	status = LTTNG_LIVE_ITERATOR_STATUS_AGAIN;
	276	}
	277	} else {
	278	status = LTTNG_LIVE_ITERATOR_STATUS_ERROR;
	279	}
7cdc2bab MD	280	end:
	281	if (fp) {
	282	int closeret;
	283
	284	closeret = fclose(fp);
	285	if (closeret) {
5278d5ba	286	BT_COMP_LOGE("Error on fclose");
7cdc2bab MD	287	}
7cdc2bab MD	288	}
6f79a7cf	289	free(metadata_buf);
7cdc2bab MD	290	return status;
	291	}
	292
	293	BT_HIDDEN
	294	int lttng_live_metadata_create_stream(struct lttng_live_session *session,
5278d5ba	295	uint64_t ctf_trace_id, uint64_t stream_id,
06994c71	296	const char *trace_name)
7cdc2bab MD	297	{
	298	struct lttng_live_metadata *metadata = NULL;
	299	struct lttng_live_trace *trace;
1f1f2720	300	struct ctf_metadata_decoder_config cfg = {
1c0ceb65	301	.log_level = session->log_level,
5278d5ba	302	.self_comp = session->self_comp,
1f1f2720 PP	303	.clock_class_offset_s = 0,
1f1f2720 PP	304	.clock_class_offset_ns = 0,
526c3a49	305	.create_trace_class = true,
1f1f2720	306	};
7cdc2bab MD	307
	308	metadata = g_new0(struct lttng_live_metadata, 1);
	309	if (!metadata) {
	310	return -1;
	311	}
1c0ceb65	312	metadata->log_level = session->log_level;
5278d5ba	313	metadata->self_comp = session->self_comp;
7cdc2bab	314	metadata->stream_id = stream_id;
bb18709b	315
16699f85	316	metadata->decoder = ctf_metadata_decoder_create(&cfg);
7cdc2bab MD	317	if (!metadata->decoder) {
	318	goto error;
	319	}
bb18709b	320	trace = lttng_live_borrow_trace(session, ctf_trace_id);
7cdc2bab MD	321	if (!trace) {
	322	goto error;
	323	}
	324	metadata->trace = trace;
	325	trace->metadata = metadata;
	326	return 0;
	327
	328	error:
	329	ctf_metadata_decoder_destroy(metadata->decoder);
	330	g_free(metadata);
	331	return -1;
	332	}
	333
	334	BT_HIDDEN
	335	void lttng_live_metadata_fini(struct lttng_live_trace *trace)
	336	{
	337	struct lttng_live_metadata *metadata = trace->metadata;
	338
	339	if (!metadata) {
	340	return;
	341	}
7cdc2bab MD	342	ctf_metadata_decoder_destroy(metadata->decoder);
7cdc2bab MD	343	trace->metadata = NULL;
7cdc2bab MD	344	g_free(metadata);
7cdc2bab MD	345	}