[babeltrace.git] / formats / lttng-live / lttng-live-plugin.c

/*
 * BabelTrace - LTTng live Output
 *
 * Copyright 2013 Julien Desfossez <jdesfossez@efficios.com>
 *                Mathieu Desnoyers <mathieu.desnoyers@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.
 */

#include <babeltrace/ctf-text/types.h>
#include <babeltrace/format.h>
#include <babeltrace/babeltrace-internal.h>
#include <inttypes.h>
#include <sys/mman.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <glib.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include "lttng-live.h"

static volatile int should_quit;

void bt_lttng_live_hook(void)
{
	/*
	 * Dummy function to prevent the linker from discarding this format as
	 * "unused" in static builds.
	 */
}

int lttng_live_should_quit(void)
{
	return should_quit;
}

static
void sighandler(int sig)
{
	switch (sig) {
	case SIGTERM:
	case SIGINT:
		should_quit = 1;
		break;
	default:
		break;
	}
}

/*
 * TODO: Eventually, this signal handler setup should be done at the
 * plugin manager level, rather than within this plugin. Beware, we are
 * not cleaning up the signal handler after plugin execution.
 */
static
int setup_sighandler(void)
{
	struct sigaction sa;
	sigset_t sigset;
	int ret;

	if ((ret = sigemptyset(&sigset)) < 0) {
		perror("sigemptyset");
		return ret;
	}
	sa.sa_handler = sighandler;
	sa.sa_mask = sigset;
	sa.sa_flags = 0;
	if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
		perror("sigaction");
		return ret;
	}
	if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
		perror("sigaction");
		return ret;
	}
	return 0;
}

/*
 * hostname parameter needs to hold MAXNAMLEN chars.
 */
static
int parse_url(const char *path, struct lttng_live_ctx *ctx)
{
	char remain[3][MAXNAMLEN] = { { 0 } };
	int ret = -1, proto, proto_offset = 0;
	size_t path_len = strlen(path);	/* not accounting \0 */

	/*
	 * Since sscanf API does not allow easily checking string length
	 * against a size defined by a macro. Test it beforehand on the
	 * input. We know the output is always <= than the input length.
	 */
	if (path_len >= MAXNAMLEN) {
		goto end;
	}
	ret = sscanf(path, "net%d://", &proto);
	if (ret < 1) {
		proto = 4;
		/* net:// */
		proto_offset = strlen("net://");
	} else {
		/* net4:// or net6:// */
		proto_offset = strlen("netX://");
	}
	if (proto_offset > path_len) {
		goto end;
	}
	if (proto == 6) {
		fprintf(stderr, "[error] IPv6 is currently unsupported by lttng-live\n");
		goto end;
	}
	/* TODO : parse for IPv6 as well */
	/* Parse the hostname or IP */
	ret = sscanf(&path[proto_offset], "%[a-zA-Z.0-9%-]%s",
		ctx->relay_hostname, remain[0]);
	if (ret == 2) {
		/* Optional port number */
		switch (remain[0][0]) {
		case ':':
			ret = sscanf(remain[0], ":%d%s", &ctx->port, remain[1]);
			/* Optional session ID with port number */
			if (ret == 2) {
				ret = sscanf(remain[1], "/%s", remain[2]);
				/* Accept 0 or 1 (optional) */
				if (ret < 0) {
					goto end;
				}
			} else if (ret == 0) {
				fprintf(stderr, "[error] Missing port number after delimitor ':'\n");
				ret = -1;
				goto end;
			}
			break;
		case '/':
			/* Optional session ID */
			ret = sscanf(remain[0], "/%s", remain[2]);
			/* Accept 0 or 1 (optional) */
			if (ret < 0) {
				goto end;
			}
			break;
		default:
			fprintf(stderr, "[error] wrong delimitor : %c\n",
				remain[0][0]);
			ret = -1;
			goto end;
		}
	}

	if (ctx->port < 0) {
		ctx->port = LTTNG_DEFAULT_NETWORK_VIEWER_PORT;
	}

	if (strlen(remain[2]) == 0) {
		printf_verbose("Connecting to hostname : %s, port : %d, "
				"proto : IPv%d\n",
				ctx->relay_hostname, ctx->port, proto);
		ret = 0;
		goto end;
	}
	ret = sscanf(remain[2], "host/%[a-zA-Z.0-9%-]/%s",
			ctx->traced_hostname, ctx->session_name);
	if (ret != 2) {
		fprintf(stderr, "[error] Format : "
			"net://<hostname>/host/<traced_hostname>/<session_name>\n");
		ret = -1;
		goto end;
	}

	printf_verbose("Connecting to hostname : %s, port : %d, "
			"traced hostname : %s, session name : %s, "
			"proto : IPv%d\n",
			ctx->relay_hostname, ctx->port, ctx->traced_hostname,
			ctx->session_name, proto);
	ret = 0;

end:
	return ret;
}

static
guint g_uint64p_hash(gconstpointer key)
{
	uint64_t v = *(uint64_t *) key;

	if (sizeof(gconstpointer) == sizeof(uint64_t)) {
		return g_direct_hash((gconstpointer) (unsigned long) v);
	} else {
		return g_direct_hash((gconstpointer) (unsigned long) (v >> 32))
			^ g_direct_hash((gconstpointer) (unsigned long) v);
	}
}

static
gboolean g_uint64p_equal(gconstpointer a, gconstpointer b)
{
	uint64_t va = *(uint64_t *) a;
	uint64_t vb = *(uint64_t *) b;

	if (va != vb)
		return FALSE;
	return TRUE;
}

static void free_session_streams(struct lttng_live_session *lsession)
{
	struct lttng_live_viewer_stream *lvstream, *tmp;

	bt_list_for_each_entry_safe(lvstream, tmp, &lsession->stream_list,
			session_stream_node) {
		/*
		 * The stream should not be in trace anymore.
		 */
		assert(!lvstream->in_trace);
		bt_list_del(&lvstream->session_stream_node);
		g_free(lvstream);
	}
}

static int lttng_live_open_trace_read(const char *path)
{
	int ret = 0;
	struct lttng_live_ctx *ctx;

	ctx = g_new0(struct lttng_live_ctx, 1);
	ctx->session = g_new0(struct lttng_live_session, 1);

	BT_INIT_LIST_HEAD(&ctx->session->stream_list);

	/* We need a pointer to the context from the packet_seek function. */
	ctx->session->ctx = ctx;

	/* HT to store the CTF traces. */
	ctx->session->ctf_traces = g_hash_table_new(g_uint64p_hash,
			g_uint64p_equal);
	ctx->port = -1;
	ctx->session_ids = g_array_new(FALSE, TRUE, sizeof(uint64_t));

	ret = parse_url(path, ctx);
	if (ret < 0) {
		goto end_free;
	}
	ret = setup_sighandler();
	if (ret < 0) {
		goto end_free;
	}
	ret = lttng_live_connect_viewer(ctx);
	if (ret < 0) {
		goto end_free;
	}
	printf_verbose("LTTng-live connected to relayd\n");

	ret = lttng_live_establish_connection(ctx);
	if (ret < 0) {
		goto end_free;
	}

	printf_verbose("Listing sessions\n");
	ret = lttng_live_list_sessions(ctx, path);
	if (ret < 0) {
		goto end_free;
	}

	if (ctx->session_ids->len > 0) {
		ret = lttng_live_read(ctx);
	}

end_free:
	g_array_free(ctx->session_ids, TRUE);
	g_hash_table_destroy(ctx->session->ctf_traces);
	free_session_streams(ctx->session);
	g_free(ctx->session);
	g_free(ctx);

	if (lttng_live_should_quit()) {
		ret = 0;
	}
	return ret;
}

static
struct bt_trace_descriptor *lttng_live_open_trace(const char *path, int flags,
		void (*packet_seek)(struct bt_stream_pos *pos, size_t index,
			int whence), FILE *metadata_fp)
{
	struct ctf_text_stream_pos *pos;

	switch (flags & O_ACCMODE) {
	case O_RDONLY:
		/* OK */
		break;
	case O_RDWR:
		fprintf(stderr, "[error] lttng live plugin cannot be used as output plugin.\n");
		goto error;
	default:
		fprintf(stderr, "[error] Incorrect open flags.\n");
		goto error;
	}

	pos = g_new0(struct ctf_text_stream_pos, 1);
	pos->parent.rw_table = NULL;
	pos->parent.event_cb = NULL;
	pos->parent.trace = &pos->trace_descriptor;
	/*
	 * Since we do *everything* in this function, we are skipping
	 * the output plugin handling that is part of Babeltrace 1.x.
	 * Therefore, don't expect the --output cmd line option to work.
	 * This limits the output of lttng-live to stderr and stdout.
	 */
	if (lttng_live_open_trace_read(path) < 0) {
		goto error;
	}
	return &pos->trace_descriptor;

error:
	return NULL;
}

static
int lttng_live_close_trace(struct bt_trace_descriptor *td)
{
	struct ctf_text_stream_pos *pos =
		container_of(td, struct ctf_text_stream_pos,
			trace_descriptor);
	g_free(pos);
	return 0;
}

static
struct bt_format lttng_live_format = {
	.open_trace = lttng_live_open_trace,
	.close_trace = lttng_live_close_trace,
};

static
void __attribute__((constructor)) lttng_live_init(void)
{
	int ret;

	lttng_live_format.name = g_quark_from_static_string("lttng-live");
	ret = bt_register_format(&lttng_live_format);
	assert(!ret);
}

static
void __attribute__((destructor)) lttng_live_exit(void)
{
	bt_unregister_format(&lttng_live_format);
}
Commit	Line	Data
4a744367 JD	1	/*
	2	* BabelTrace - LTTng live Output
	3	*
	4	* Copyright 2013 Julien Desfossez <jdesfossez@efficios.com>
	5	* Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	6	*
	7	* Permission is hereby granted, free of charge, to any person obtaining a copy
	8	* of this software and associated documentation files (the "Software"), to deal
	9	* in the Software without restriction, including without limitation the rights
	10	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	11	* copies of the Software, and to permit persons to whom the Software is
	12	* furnished to do so, subject to the following conditions:
	13	*
	14	* The above copyright notice and this permission notice shall be included in
	15	* all copies or substantial portions of the Software.
	16	*
	17	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	18	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	19	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	20	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	21	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	22	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	23	* SOFTWARE.
	24	*/
	25
	26	#include <babeltrace/ctf-text/types.h>
	27	#include <babeltrace/format.h>
	28	#include <babeltrace/babeltrace-internal.h>
	29	#include <inttypes.h>
	30	#include <sys/mman.h>
	31	#include <errno.h>
	32	#include <sys/types.h>
	33	#include <sys/stat.h>
	34	#include <fcntl.h>
	35	#include <dirent.h>
	36	#include <glib.h>
	37	#include <unistd.h>
	38	#include <stdlib.h>
8ace20bf	39	#include <signal.h>
c98627ca	40	#include "lttng-live.h"
4a744367	41
8ace20bf MD	42	static volatile int should_quit;
8ace20bf MD	43
c13e6f6d JG	44	void bt_lttng_live_hook(void)
	45	{
	46	/*
	47	* Dummy function to prevent the linker from discarding this format as
	48	* "unused" in static builds.
	49	*/
	50	}
	51
8ace20bf MD	52	int lttng_live_should_quit(void)
	53	{
	54	return should_quit;
	55	}
	56
	57	static
	58	void sighandler(int sig)
	59	{
	60	switch (sig) {
	61	case SIGTERM:
	62	case SIGINT:
	63	should_quit = 1;
	64	break;
	65	default:
	66	break;
	67	}
	68	}
	69
	70	/*
	71	* TODO: Eventually, this signal handler setup should be done at the
	72	* plugin manager level, rather than within this plugin. Beware, we are
	73	* not cleaning up the signal handler after plugin execution.
	74	*/
	75	static
	76	int setup_sighandler(void)
	77	{
	78	struct sigaction sa;
	79	sigset_t sigset;
	80	int ret;
	81
	82	if ((ret = sigemptyset(&sigset)) < 0) {
	83	perror("sigemptyset");
	84	return ret;
	85	}
	86	sa.sa_handler = sighandler;
	87	sa.sa_mask = sigset;
	88	sa.sa_flags = 0;
	89	if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
	90	perror("sigaction");
	91	return ret;
	92	}
	93	if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
	94	perror("sigaction");
	95	return ret;
	96	}
	97	return 0;
	98	}
	99
e84d6f79	100	/*
0206bb4a	101	* hostname parameter needs to hold MAXNAMLEN chars.
e84d6f79	102	*/
b5a1fa45 JD	103	static
b5a1fa45 JD	104	int parse_url(const char path, struct lttng_live_ctx ctx)
4a744367	105	{
5223ed80	106	char remain[3][MAXNAMLEN] = { { 0 } };
e84d6f79	107	int ret = -1, proto, proto_offset = 0;
5fe17d06	108	size_t path_len = strlen(path); /* not accounting \0 */
4a744367	109
e84d6f79 MD	110	/*
	111	* Since sscanf API does not allow easily checking string length
	112	* against a size defined by a macro. Test it beforehand on the
	113	* input. We know the output is always <= than the input length.
	114	*/
0206bb4a	115	if (path_len >= MAXNAMLEN) {
e84d6f79 MD	116	goto end;
	117	}
	118	ret = sscanf(path, "net%d://", &proto);
	119	if (ret < 1) {
4a744367 JD	120	proto = 4;
	121	/* net:// */
	122	proto_offset = strlen("net://");
	123	} else {
	124	/* net4:// or net6:// */
	125	proto_offset = strlen("netX://");
	126	}
e84d6f79 MD	127	if (proto_offset > path_len) {
	128	goto end;
	129	}
fdfb7392 JG	130	if (proto == 6) {
	131	fprintf(stderr, "[error] IPv6 is currently unsupported by lttng-live\n");
	132	goto end;
	133	}
4a744367 JD	134	/* TODO : parse for IPv6 as well */
4a744367 JD	135	/* Parse the hostname or IP */
e84d6f79	136	ret = sscanf(&path[proto_offset], "%[a-zA-Z.0-9%-]%s",
b5a1fa45	137	ctx->relay_hostname, remain[0]);
4a744367 JD	138	if (ret == 2) {
4a744367 JD	139	/* Optional port number */
e84d6f79 MD	140	switch (remain[0][0]) {
e84d6f79 MD	141	case ':':
b5a1fa45	142	ret = sscanf(remain[0], ":%d%s", &ctx->port, remain[1]);
4a744367 JD	143	/* Optional session ID with port number */
4a744367 JD	144	if (ret == 2) {
2acdc547	145	ret = sscanf(remain[1], "/%s", remain[2]);
e84d6f79 MD	146	/* Accept 0 or 1 (optional) */
	147	if (ret < 0) {
	148	goto end;
	149	}
9010d19c	150	} else if (ret == 0) {
2a6d197b MD	151	fprintf(stderr, "[error] Missing port number after delimitor ':'\n");
	152	ret = -1;
	153	goto end;
4a744367	154	}
e84d6f79 MD	155	break;
e84d6f79 MD	156	case '/':
4a744367	157	/* Optional session ID */
2acdc547	158	ret = sscanf(remain[0], "/%s", remain[2]);
e84d6f79 MD	159	/* Accept 0 or 1 (optional) */
	160	if (ret < 0) {
	161	goto end;
	162	}
	163	break;
	164	default:
4a744367	165	fprintf(stderr, "[error] wrong delimitor : %c\n",
e84d6f79	166	remain[0][0]);
4a744367 JD	167	ret = -1;
	168	goto end;
	169	}
	170	}
	171
49a4acef	172	if (ctx->port < 0) {
b5a1fa45	173	ctx->port = LTTNG_DEFAULT_NETWORK_VIEWER_PORT;
49a4acef	174	}
4a744367	175
2acdc547	176	if (strlen(remain[2]) == 0) {
4a744367 JD	177	printf_verbose("Connecting to hostname : %s, port : %d, "
4a744367 JD	178	"proto : IPv%d\n",
b5a1fa45	179	ctx->relay_hostname, ctx->port, proto);
2acdc547 JD	180	ret = 0;
	181	goto end;
	182	}
b5a1fa45 JD	183	ret = sscanf(remain[2], "host/%[a-zA-Z.0-9%-]/%s",
	184	ctx->traced_hostname, ctx->session_name);
	185	if (ret != 2) {
	186	fprintf(stderr, "[error] Format : "
	187	"net://<hostname>/host/<traced_hostname>/<session_name>\n");
340a47b8	188	ret = -1;
b5a1fa45 JD	189	goto end;
b5a1fa45 JD	190	}
2acdc547 JD	191
2acdc547 JD	192	printf_verbose("Connecting to hostname : %s, port : %d, "
b5a1fa45 JD	193	"traced hostname : %s, session name : %s, "
	194	"proto : IPv%d\n",
	195	ctx->relay_hostname, ctx->port, ctx->traced_hostname,
	196	ctx->session_name, proto);
4a744367 JD	197	ret = 0;
	198
	199	end:
	200	return ret;
	201	}
	202
37307240 MD	203	static
	204	guint g_uint64p_hash(gconstpointer key)
	205	{
	206	uint64_t v = (uint64_t ) key;
	207
	208	if (sizeof(gconstpointer) == sizeof(uint64_t)) {
	209	return g_direct_hash((gconstpointer) (unsigned long) v);
	210	} else {
	211	return g_direct_hash((gconstpointer) (unsigned long) (v >> 32))
	212	^ g_direct_hash((gconstpointer) (unsigned long) v);
	213	}
	214	}
	215
	216	static
	217	gboolean g_uint64p_equal(gconstpointer a, gconstpointer b)
	218	{
	219	uint64_t va = (uint64_t ) a;
	220	uint64_t vb = (uint64_t ) b;
	221
	222	if (va != vb)
	223	return FALSE;
	224	return TRUE;
	225	}
	226
b5e7994d MD	227	static void free_session_streams(struct lttng_live_session *lsession)
	228	{
	229	struct lttng_live_viewer_stream lvstream, tmp;
	230
	231	bt_list_for_each_entry_safe(lvstream, tmp, &lsession->stream_list,
e88db11d MD	232	session_stream_node) {
	233	/*
	234	* The stream should not be in trace anymore.
	235	*/
	236	assert(!lvstream->in_trace);
	237	bt_list_del(&lvstream->session_stream_node);
b5e7994d MD	238	g_free(lvstream);
	239	}
	240	}
	241
4a744367 JD	242	static int lttng_live_open_trace_read(const char *path)
4a744367 JD	243	{
4a744367	244	int ret = 0;
b5a1fa45	245	struct lttng_live_ctx *ctx;
4a744367	246
b5a1fa45 JD	247	ctx = g_new0(struct lttng_live_ctx, 1);
b5a1fa45 JD	248	ctx->session = g_new0(struct lttng_live_session, 1);
3af4fc48	249
b5e7994d MD	250	BT_INIT_LIST_HEAD(&ctx->session->stream_list);
b5e7994d MD	251
4a744367	252	/* We need a pointer to the context from the packet_seek function. */
b5a1fa45	253	ctx->session->ctx = ctx;
4a744367 JD	254
4a744367 JD	255	/* HT to store the CTF traces. */
37307240 MD	256	ctx->session->ctf_traces = g_hash_table_new(g_uint64p_hash,
37307240 MD	257	g_uint64p_equal);
b5a1fa45 JD	258	ctx->port = -1;
b5a1fa45 JD	259	ctx->session_ids = g_array_new(FALSE, TRUE, sizeof(uint64_t));
4a744367	260
b5a1fa45	261	ret = parse_url(path, ctx);
4a744367 JD	262	if (ret < 0) {
	263	goto end_free;
	264	}
8ace20bf MD	265	ret = setup_sighandler();
	266	if (ret < 0) {
	267	goto end_free;
	268	}
b5a1fa45	269	ret = lttng_live_connect_viewer(ctx);
4a744367	270	if (ret < 0) {
4a744367 JD	271	goto end_free;
	272	}
	273	printf_verbose("LTTng-live connected to relayd\n");
	274
b5a1fa45	275	ret = lttng_live_establish_connection(ctx);
4a744367 JD	276	if (ret < 0) {
	277	goto end_free;
	278	}
	279
b5a1fa45 JD	280	printf_verbose("Listing sessions\n");
	281	ret = lttng_live_list_sessions(ctx, path);
	282	if (ret < 0) {
b5a1fa45	283	goto end_free;
4a744367 JD	284	}
4a744367 JD	285
49a4acef	286	if (ctx->session_ids->len > 0) {
28756729	287	ret = lttng_live_read(ctx);
49a4acef	288	}
b5a1fa45	289
4a744367	290	end_free:
51a19e72	291	g_array_free(ctx->session_ids, TRUE);
b5a1fa45	292	g_hash_table_destroy(ctx->session->ctf_traces);
b5e7994d	293	free_session_streams(ctx->session);
b5a1fa45	294	g_free(ctx->session);
b5a1fa45	295	g_free(ctx);
8ace20bf MD	296
	297	if (lttng_live_should_quit()) {
	298	ret = 0;
	299	}
4a744367 JD	300	return ret;
	301	}
	302
	303	static
	304	struct bt_trace_descriptor lttng_live_open_trace(const char path, int flags,
	305	void (packet_seek)(struct bt_stream_pos pos, size_t index,
	306	int whence), FILE *metadata_fp)
	307	{
	308	struct ctf_text_stream_pos *pos;
	309
	310	switch (flags & O_ACCMODE) {
	311	case O_RDONLY:
	312	/* OK */
	313	break;
	314	case O_RDWR:
	315	fprintf(stderr, "[error] lttng live plugin cannot be used as output plugin.\n");
	316	goto error;
	317	default:
	318	fprintf(stderr, "[error] Incorrect open flags.\n");
	319	goto error;
	320	}
	321
	322	pos = g_new0(struct ctf_text_stream_pos, 1);
	323	pos->parent.rw_table = NULL;
	324	pos->parent.event_cb = NULL;
	325	pos->parent.trace = &pos->trace_descriptor;
857eaa68 MD	326	/*
	327	* Since we do everything in this function, we are skipping
	328	* the output plugin handling that is part of Babeltrace 1.x.
	329	* Therefore, don't expect the --output cmd line option to work.
	330	* This limits the output of lttng-live to stderr and stdout.
	331	*/
28756729 JG	332	if (lttng_live_open_trace_read(path) < 0) {
	333	goto error;
	334	}
4a744367 JD	335	return &pos->trace_descriptor;
	336
	337	error:
	338	return NULL;
	339	}
	340
	341	static
	342	int lttng_live_close_trace(struct bt_trace_descriptor *td)
	343	{
	344	struct ctf_text_stream_pos *pos =
	345	container_of(td, struct ctf_text_stream_pos,
	346	trace_descriptor);
9b6ae25b	347	g_free(pos);
4a744367 JD	348	return 0;
	349	}
	350
	351	static
	352	struct bt_format lttng_live_format = {
	353	.open_trace = lttng_live_open_trace,
	354	.close_trace = lttng_live_close_trace,
	355	};
	356
	357	static
	358	void __attribute__((constructor)) lttng_live_init(void)
	359	{
	360	int ret;
	361
	362	lttng_live_format.name = g_quark_from_static_string("lttng-live");
	363	ret = bt_register_format(&lttng_live_format);
	364	assert(!ret);
	365	}
	366
	367	static
	368	void __attribute__((destructor)) lttng_live_exit(void)
	369	{
	370	bt_unregister_format(&lttng_live_format);
	371	}