Simplify free() of channel attribute
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License, version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <inttypes.h>
22 #include <urcu/list.h>
23 #include <urcu/uatomic.h>
24
25 #include <common/defaults.h>
26 #include <common/common.h>
27 #include <common/sessiond-comm/sessiond-comm.h>
28 #include <common/relayd/relayd.h>
29 #include <common/utils.h>
30 #include <common/compat/string.h>
31 #include <common/kernel-ctl/kernel-ctl.h>
32
33 #include "channel.h"
34 #include "consumer.h"
35 #include "event.h"
36 #include "health-sessiond.h"
37 #include "kernel.h"
38 #include "kernel-consumer.h"
39 #include "lttng-sessiond.h"
40 #include "utils.h"
41 #include "syscall.h"
42 #include "agent.h"
43 #include "buffer-registry.h"
44
45 #include "cmd.h"
46
47 /*
48 * Used to keep a unique index for each relayd socket created where this value
49 * is associated with streams on the consumer so it can match the right relayd
50 * to send to. It must be accessed with the relayd_net_seq_idx_lock
51 * held.
52 */
53 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
54 static uint64_t relayd_net_seq_idx;
55
56 static int validate_event_name(const char *);
57 static int validate_ust_event_name(const char *);
58 static int cmd_enable_event_internal(struct ltt_session *session,
59 struct lttng_domain *domain,
60 char *channel_name, struct lttng_event *event,
61 char *filter_expression,
62 struct lttng_filter_bytecode *filter,
63 struct lttng_event_exclusion *exclusion,
64 int wpipe);
65
66 /*
67 * Create a session path used by list_lttng_sessions for the case that the
68 * session consumer is on the network.
69 */
70 static int build_network_session_path(char *dst, size_t size,
71 struct ltt_session *session)
72 {
73 int ret, kdata_port, udata_port;
74 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
75 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
76
77 assert(session);
78 assert(dst);
79
80 memset(tmp_urls, 0, sizeof(tmp_urls));
81 memset(tmp_uurl, 0, sizeof(tmp_uurl));
82
83 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
84
85 if (session->kernel_session && session->kernel_session->consumer) {
86 kuri = &session->kernel_session->consumer->dst.net.control;
87 kdata_port = session->kernel_session->consumer->dst.net.data.port;
88 }
89
90 if (session->ust_session && session->ust_session->consumer) {
91 uuri = &session->ust_session->consumer->dst.net.control;
92 udata_port = session->ust_session->consumer->dst.net.data.port;
93 }
94
95 if (uuri == NULL && kuri == NULL) {
96 uri = &session->consumer->dst.net.control;
97 kdata_port = session->consumer->dst.net.data.port;
98 } else if (kuri && uuri) {
99 ret = uri_compare(kuri, uuri);
100 if (ret) {
101 /* Not Equal */
102 uri = kuri;
103 /* Build uuri URL string */
104 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
105 if (ret < 0) {
106 goto error;
107 }
108 } else {
109 uri = kuri;
110 }
111 } else if (kuri && uuri == NULL) {
112 uri = kuri;
113 } else if (uuri && kuri == NULL) {
114 uri = uuri;
115 }
116
117 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
118 if (ret < 0) {
119 goto error;
120 }
121
122 /*
123 * Do we have a UST url set. If yes, this means we have both kernel and UST
124 * to print.
125 */
126 if (*tmp_uurl != '\0') {
127 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
128 tmp_urls, kdata_port, tmp_uurl, udata_port);
129 } else {
130 int dport;
131 if (kuri || (!kuri && !uuri)) {
132 dport = kdata_port;
133 } else {
134 /* No kernel URI, use the UST port. */
135 dport = udata_port;
136 }
137 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
138 }
139
140 error:
141 return ret;
142 }
143
144 /*
145 * Get run-time attributes if the session has been started (discarded events,
146 * lost packets).
147 */
148 static int get_kernel_runtime_stats(struct ltt_session *session,
149 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
150 uint64_t *lost_packets)
151 {
152 int ret;
153
154 if (!session->has_been_started) {
155 ret = 0;
156 *discarded_events = 0;
157 *lost_packets = 0;
158 goto end;
159 }
160
161 ret = consumer_get_discarded_events(session->id, kchan->fd,
162 session->kernel_session->consumer,
163 discarded_events);
164 if (ret < 0) {
165 goto end;
166 }
167
168 ret = consumer_get_lost_packets(session->id, kchan->fd,
169 session->kernel_session->consumer,
170 lost_packets);
171 if (ret < 0) {
172 goto end;
173 }
174
175 end:
176 return ret;
177 }
178
179 /*
180 * Get run-time attributes if the session has been started (discarded events,
181 * lost packets).
182 */
183 static int get_ust_runtime_stats(struct ltt_session *session,
184 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
185 uint64_t *lost_packets)
186 {
187 int ret;
188 struct ltt_ust_session *usess;
189
190 if (!discarded_events || !lost_packets) {
191 ret = -1;
192 goto end;
193 }
194
195 usess = session->ust_session;
196 assert(discarded_events);
197 assert(lost_packets);
198
199 if (!usess || !session->has_been_started) {
200 *discarded_events = 0;
201 *lost_packets = 0;
202 ret = 0;
203 goto end;
204 }
205
206 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
207 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
208 &usess->buffer_reg_uid_list,
209 usess->consumer, uchan->id,
210 uchan->attr.overwrite,
211 discarded_events,
212 lost_packets);
213 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
214 ret = ust_app_pid_get_channel_runtime_stats(usess,
215 uchan, usess->consumer,
216 uchan->attr.overwrite,
217 discarded_events,
218 lost_packets);
219 if (ret < 0) {
220 goto end;
221 }
222 *discarded_events += uchan->per_pid_closed_app_discarded;
223 *lost_packets += uchan->per_pid_closed_app_lost;
224 } else {
225 ERR("Unsupported buffer type");
226 assert(0);
227 ret = -1;
228 goto end;
229 }
230
231 end:
232 return ret;
233 }
234
235 /*
236 * Fill lttng_channel array of all channels.
237 */
238 static void list_lttng_channels(enum lttng_domain_type domain,
239 struct ltt_session *session, struct lttng_channel *channels,
240 struct lttcomm_channel_extended *chan_exts)
241 {
242 int i = 0, ret;
243 struct ltt_kernel_channel *kchan;
244
245 DBG("Listing channels for session %s", session->name);
246
247 switch (domain) {
248 case LTTNG_DOMAIN_KERNEL:
249 /* Kernel channels */
250 if (session->kernel_session != NULL) {
251 cds_list_for_each_entry(kchan,
252 &session->kernel_session->channel_list.head, list) {
253 uint64_t discarded_events, lost_packets;
254
255 ret = get_kernel_runtime_stats(session, kchan,
256 &discarded_events, &lost_packets);
257 if (ret < 0) {
258 goto end;
259 }
260 /* Copy lttng_channel struct to array */
261 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
262 channels[i].enabled = kchan->enabled;
263 chan_exts[i].discarded_events =
264 discarded_events;
265 chan_exts[i].lost_packets = lost_packets;
266 i++;
267 }
268 }
269 break;
270 case LTTNG_DOMAIN_UST:
271 {
272 struct lttng_ht_iter iter;
273 struct ltt_ust_channel *uchan;
274
275 rcu_read_lock();
276 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
277 &iter.iter, uchan, node.node) {
278 uint64_t discarded_events = 0, lost_packets = 0;
279
280 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
281 channels[i].attr.overwrite = uchan->attr.overwrite;
282 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
283 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
284 channels[i].attr.switch_timer_interval =
285 uchan->attr.switch_timer_interval;
286 channels[i].attr.read_timer_interval =
287 uchan->attr.read_timer_interval;
288 channels[i].enabled = uchan->enabled;
289 channels[i].attr.tracefile_size = uchan->tracefile_size;
290 channels[i].attr.tracefile_count = uchan->tracefile_count;
291
292 /*
293 * Map enum lttng_ust_output to enum lttng_event_output.
294 */
295 switch (uchan->attr.output) {
296 case LTTNG_UST_MMAP:
297 channels[i].attr.output = LTTNG_EVENT_MMAP;
298 break;
299 default:
300 /*
301 * LTTNG_UST_MMAP is the only supported UST
302 * output mode.
303 */
304 assert(0);
305 break;
306 }
307
308 ret = get_ust_runtime_stats(session, uchan,
309 &discarded_events, &lost_packets);
310 if (ret < 0) {
311 break;
312 }
313 chan_exts[i].discarded_events = discarded_events;
314 chan_exts[i].lost_packets = lost_packets;
315 i++;
316 }
317 rcu_read_unlock();
318 break;
319 }
320 default:
321 break;
322 }
323
324 end:
325 return;
326 }
327
328 static void increment_extended_len(const char *filter_expression,
329 struct lttng_event_exclusion *exclusion, size_t *extended_len)
330 {
331 *extended_len += sizeof(struct lttcomm_event_extended_header);
332
333 if (filter_expression) {
334 *extended_len += strlen(filter_expression) + 1;
335 }
336
337 if (exclusion) {
338 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
339 }
340 }
341
342 static void append_extended_info(const char *filter_expression,
343 struct lttng_event_exclusion *exclusion, void **extended_at)
344 {
345 struct lttcomm_event_extended_header extended_header;
346 size_t filter_len = 0;
347 size_t nb_exclusions = 0;
348
349 if (filter_expression) {
350 filter_len = strlen(filter_expression) + 1;
351 }
352
353 if (exclusion) {
354 nb_exclusions = exclusion->count;
355 }
356
357 /* Set header fields */
358 extended_header.filter_len = filter_len;
359 extended_header.nb_exclusions = nb_exclusions;
360
361 /* Copy header */
362 memcpy(*extended_at, &extended_header, sizeof(extended_header));
363 *extended_at += sizeof(extended_header);
364
365 /* Copy filter string */
366 if (filter_expression) {
367 memcpy(*extended_at, filter_expression, filter_len);
368 *extended_at += filter_len;
369 }
370
371 /* Copy exclusion names */
372 if (exclusion) {
373 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
374
375 memcpy(*extended_at, &exclusion->names, len);
376 *extended_at += len;
377 }
378 }
379
380 /*
381 * Create a list of agent domain events.
382 *
383 * Return number of events in list on success or else a negative value.
384 */
385 static int list_lttng_agent_events(struct agent *agt,
386 struct lttng_event **events, size_t *total_size)
387 {
388 int i = 0, ret = 0;
389 unsigned int nb_event = 0;
390 struct agent_event *event;
391 struct lttng_event *tmp_events;
392 struct lttng_ht_iter iter;
393 size_t extended_len = 0;
394 void *extended_at;
395
396 assert(agt);
397 assert(events);
398
399 DBG3("Listing agent events");
400
401 rcu_read_lock();
402 nb_event = lttng_ht_get_count(agt->events);
403 rcu_read_unlock();
404 if (nb_event == 0) {
405 ret = nb_event;
406 *total_size = 0;
407 goto error;
408 }
409
410 /* Compute required extended infos size */
411 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
412
413 /*
414 * This is only valid because the commands which add events are
415 * processed in the same thread as the listing.
416 */
417 rcu_read_lock();
418 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
419 increment_extended_len(event->filter_expression, NULL,
420 &extended_len);
421 }
422 rcu_read_unlock();
423
424 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
425 tmp_events = zmalloc(*total_size);
426 if (!tmp_events) {
427 PERROR("zmalloc agent events session");
428 ret = -LTTNG_ERR_FATAL;
429 goto error;
430 }
431
432 extended_at = ((uint8_t *) tmp_events) +
433 nb_event * sizeof(struct lttng_event);
434
435 rcu_read_lock();
436 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
437 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
438 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
439 tmp_events[i].enabled = event->enabled;
440 tmp_events[i].loglevel = event->loglevel_value;
441 tmp_events[i].loglevel_type = event->loglevel_type;
442 i++;
443
444 /* Append extended info */
445 append_extended_info(event->filter_expression, NULL,
446 &extended_at);
447 }
448 rcu_read_unlock();
449
450 *events = tmp_events;
451 ret = nb_event;
452
453 error:
454 assert(nb_event == i);
455 return ret;
456 }
457
458 /*
459 * Create a list of ust global domain events.
460 */
461 static int list_lttng_ust_global_events(char *channel_name,
462 struct ltt_ust_domain_global *ust_global,
463 struct lttng_event **events, size_t *total_size)
464 {
465 int i = 0, ret = 0;
466 unsigned int nb_event = 0;
467 struct lttng_ht_iter iter;
468 struct lttng_ht_node_str *node;
469 struct ltt_ust_channel *uchan;
470 struct ltt_ust_event *uevent;
471 struct lttng_event *tmp;
472 size_t extended_len = 0;
473 void *extended_at;
474
475 DBG("Listing UST global events for channel %s", channel_name);
476
477 rcu_read_lock();
478
479 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
480 node = lttng_ht_iter_get_node_str(&iter);
481 if (node == NULL) {
482 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
483 goto end;
484 }
485
486 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
487
488 nb_event = lttng_ht_get_count(uchan->events);
489 if (nb_event == 0) {
490 ret = nb_event;
491 *total_size = 0;
492 goto end;
493 }
494
495 DBG3("Listing UST global %d events", nb_event);
496
497 /* Compute required extended infos size */
498 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
499 if (uevent->internal) {
500 nb_event--;
501 continue;
502 }
503
504 increment_extended_len(uevent->filter_expression,
505 uevent->exclusion, &extended_len);
506 }
507 if (nb_event == 0) {
508 /* All events are internal, skip. */
509 ret = 0;
510 *total_size = 0;
511 goto end;
512 }
513
514 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
515 tmp = zmalloc(*total_size);
516 if (tmp == NULL) {
517 ret = -LTTNG_ERR_FATAL;
518 goto end;
519 }
520
521 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
522
523 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
524 if (uevent->internal) {
525 /* This event should remain hidden from clients */
526 continue;
527 }
528 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
529 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
530 tmp[i].enabled = uevent->enabled;
531
532 switch (uevent->attr.instrumentation) {
533 case LTTNG_UST_TRACEPOINT:
534 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
535 break;
536 case LTTNG_UST_PROBE:
537 tmp[i].type = LTTNG_EVENT_PROBE;
538 break;
539 case LTTNG_UST_FUNCTION:
540 tmp[i].type = LTTNG_EVENT_FUNCTION;
541 break;
542 }
543
544 tmp[i].loglevel = uevent->attr.loglevel;
545 switch (uevent->attr.loglevel_type) {
546 case LTTNG_UST_LOGLEVEL_ALL:
547 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
548 break;
549 case LTTNG_UST_LOGLEVEL_RANGE:
550 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
551 break;
552 case LTTNG_UST_LOGLEVEL_SINGLE:
553 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
554 break;
555 }
556 if (uevent->filter) {
557 tmp[i].filter = 1;
558 }
559 if (uevent->exclusion) {
560 tmp[i].exclusion = 1;
561 }
562 i++;
563
564 /* Append extended info */
565 append_extended_info(uevent->filter_expression,
566 uevent->exclusion, &extended_at);
567 }
568
569 ret = nb_event;
570 *events = tmp;
571 end:
572 rcu_read_unlock();
573 return ret;
574 }
575
576 /*
577 * Fill lttng_event array of all kernel events in the channel.
578 */
579 static int list_lttng_kernel_events(char *channel_name,
580 struct ltt_kernel_session *kernel_session,
581 struct lttng_event **events, size_t *total_size)
582 {
583 int i = 0, ret;
584 unsigned int nb_event;
585 struct ltt_kernel_event *event;
586 struct ltt_kernel_channel *kchan;
587 size_t extended_len = 0;
588 void *extended_at;
589
590 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
591 if (kchan == NULL) {
592 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
593 goto error;
594 }
595
596 nb_event = kchan->event_count;
597
598 DBG("Listing events for channel %s", kchan->channel->name);
599
600 if (nb_event == 0) {
601 *total_size = 0;
602 *events = NULL;
603 goto end;
604 }
605
606 /* Compute required extended infos size */
607 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
608 increment_extended_len(event->filter_expression, NULL,
609 &extended_len);
610 }
611
612 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
613 *events = zmalloc(*total_size);
614 if (*events == NULL) {
615 ret = LTTNG_ERR_FATAL;
616 goto error;
617 }
618
619 extended_at = ((void *) *events) +
620 nb_event * sizeof(struct lttng_event);
621
622 /* Kernel channels */
623 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
624 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
625 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
626 (*events)[i].enabled = event->enabled;
627 (*events)[i].filter =
628 (unsigned char) !!event->filter_expression;
629
630 switch (event->event->instrumentation) {
631 case LTTNG_KERNEL_TRACEPOINT:
632 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
633 break;
634 case LTTNG_KERNEL_KRETPROBE:
635 (*events)[i].type = LTTNG_EVENT_FUNCTION;
636 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
637 sizeof(struct lttng_kernel_kprobe));
638 break;
639 case LTTNG_KERNEL_KPROBE:
640 (*events)[i].type = LTTNG_EVENT_PROBE;
641 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
642 sizeof(struct lttng_kernel_kprobe));
643 break;
644 case LTTNG_KERNEL_FUNCTION:
645 (*events)[i].type = LTTNG_EVENT_FUNCTION;
646 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
647 sizeof(struct lttng_kernel_function));
648 break;
649 case LTTNG_KERNEL_NOOP:
650 (*events)[i].type = LTTNG_EVENT_NOOP;
651 break;
652 case LTTNG_KERNEL_SYSCALL:
653 (*events)[i].type = LTTNG_EVENT_SYSCALL;
654 break;
655 case LTTNG_KERNEL_ALL:
656 assert(0);
657 break;
658 }
659 i++;
660
661 /* Append extended info */
662 append_extended_info(event->filter_expression, NULL,
663 &extended_at);
664 }
665
666 end:
667 return nb_event;
668
669 error:
670 /* Negate the error code to differentiate the size from an error */
671 return -ret;
672 }
673
674 /*
675 * Add URI so the consumer output object. Set the correct path depending on the
676 * domain adding the default trace directory.
677 */
678 static int add_uri_to_consumer(struct consumer_output *consumer,
679 struct lttng_uri *uri, enum lttng_domain_type domain,
680 const char *session_name)
681 {
682 int ret = LTTNG_OK;
683 const char *default_trace_dir;
684
685 assert(uri);
686
687 if (consumer == NULL) {
688 DBG("No consumer detected. Don't add URI. Stopping.");
689 ret = LTTNG_ERR_NO_CONSUMER;
690 goto error;
691 }
692
693 switch (domain) {
694 case LTTNG_DOMAIN_KERNEL:
695 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
696 break;
697 case LTTNG_DOMAIN_UST:
698 default_trace_dir = DEFAULT_UST_TRACE_DIR;
699 break;
700 default:
701 /*
702 * This case is possible is we try to add the URI to the global tracing
703 * session consumer object which in this case there is no subdir.
704 */
705 default_trace_dir = "";
706 }
707
708 switch (uri->dtype) {
709 case LTTNG_DST_IPV4:
710 case LTTNG_DST_IPV6:
711 DBG2("Setting network URI to consumer");
712
713 if (consumer->type == CONSUMER_DST_NET) {
714 if ((uri->stype == LTTNG_STREAM_CONTROL &&
715 consumer->dst.net.control_isset) ||
716 (uri->stype == LTTNG_STREAM_DATA &&
717 consumer->dst.net.data_isset)) {
718 ret = LTTNG_ERR_URL_EXIST;
719 goto error;
720 }
721 } else {
722 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
723 }
724
725 consumer->type = CONSUMER_DST_NET;
726
727 /* Set URI into consumer output object */
728 ret = consumer_set_network_uri(consumer, uri);
729 if (ret < 0) {
730 ret = -ret;
731 goto error;
732 } else if (ret == 1) {
733 /*
734 * URI was the same in the consumer so we do not append the subdir
735 * again so to not duplicate output dir.
736 */
737 ret = LTTNG_OK;
738 goto error;
739 }
740
741 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
742 ret = consumer_set_subdir(consumer, session_name);
743 if (ret < 0) {
744 ret = LTTNG_ERR_FATAL;
745 goto error;
746 }
747 }
748
749 if (uri->stype == LTTNG_STREAM_CONTROL) {
750 /* On a new subdir, reappend the default trace dir. */
751 strncat(consumer->subdir, default_trace_dir,
752 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
753 DBG3("Append domain trace name to subdir %s", consumer->subdir);
754 }
755
756 break;
757 case LTTNG_DST_PATH:
758 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
759 memset(consumer->dst.trace_path, 0,
760 sizeof(consumer->dst.trace_path));
761 strncpy(consumer->dst.trace_path, uri->dst.path,
762 sizeof(consumer->dst.trace_path));
763 /* Append default trace dir */
764 strncat(consumer->dst.trace_path, default_trace_dir,
765 sizeof(consumer->dst.trace_path) -
766 strlen(consumer->dst.trace_path) - 1);
767 /* Flag consumer as local. */
768 consumer->type = CONSUMER_DST_LOCAL;
769 break;
770 }
771
772 ret = LTTNG_OK;
773
774 error:
775 return ret;
776 }
777
778 /*
779 * Init tracing by creating trace directory and sending fds kernel consumer.
780 */
781 static int init_kernel_tracing(struct ltt_kernel_session *session)
782 {
783 int ret = 0;
784 struct lttng_ht_iter iter;
785 struct consumer_socket *socket;
786
787 assert(session);
788
789 rcu_read_lock();
790
791 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
792 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
793 socket, node.node) {
794 pthread_mutex_lock(socket->lock);
795 ret = kernel_consumer_send_session(socket, session);
796 pthread_mutex_unlock(socket->lock);
797 if (ret < 0) {
798 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
799 goto error;
800 }
801 }
802 }
803
804 error:
805 rcu_read_unlock();
806 return ret;
807 }
808
809 /*
810 * Create a socket to the relayd using the URI.
811 *
812 * On success, the relayd_sock pointer is set to the created socket.
813 * Else, it's stays untouched and a lttcomm error code is returned.
814 */
815 static int create_connect_relayd(struct lttng_uri *uri,
816 struct lttcomm_relayd_sock **relayd_sock,
817 struct consumer_output *consumer)
818 {
819 int ret;
820 struct lttcomm_relayd_sock *rsock;
821
822 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
823 RELAYD_VERSION_COMM_MINOR);
824 if (!rsock) {
825 ret = LTTNG_ERR_FATAL;
826 goto error;
827 }
828
829 /*
830 * Connect to relayd so we can proceed with a session creation. This call
831 * can possibly block for an arbitrary amount of time to set the health
832 * state to be in poll execution.
833 */
834 health_poll_entry();
835 ret = relayd_connect(rsock);
836 health_poll_exit();
837 if (ret < 0) {
838 ERR("Unable to reach lttng-relayd");
839 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
840 goto free_sock;
841 }
842
843 /* Create socket for control stream. */
844 if (uri->stype == LTTNG_STREAM_CONTROL) {
845 DBG3("Creating relayd stream socket from URI");
846
847 /* Check relayd version */
848 ret = relayd_version_check(rsock);
849 if (ret < 0) {
850 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
851 goto close_sock;
852 }
853 consumer->relay_major_version = rsock->major;
854 consumer->relay_minor_version = rsock->minor;
855 } else if (uri->stype == LTTNG_STREAM_DATA) {
856 DBG3("Creating relayd data socket from URI");
857 } else {
858 /* Command is not valid */
859 ERR("Relayd invalid stream type: %d", uri->stype);
860 ret = LTTNG_ERR_INVALID;
861 goto close_sock;
862 }
863
864 *relayd_sock = rsock;
865
866 return LTTNG_OK;
867
868 close_sock:
869 /* The returned value is not useful since we are on an error path. */
870 (void) relayd_close(rsock);
871 free_sock:
872 free(rsock);
873 error:
874 return ret;
875 }
876
877 /*
878 * Connect to the relayd using URI and send the socket to the right consumer.
879 */
880 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
881 unsigned int session_id, struct lttng_uri *relayd_uri,
882 struct consumer_output *consumer,
883 struct consumer_socket *consumer_sock,
884 char *session_name, char *hostname, int session_live_timer)
885 {
886 int ret;
887 struct lttcomm_relayd_sock *rsock = NULL;
888
889 /* Connect to relayd and make version check if uri is the control. */
890 ret = create_connect_relayd(relayd_uri, &rsock, consumer);
891 if (ret != LTTNG_OK) {
892 goto error;
893 }
894 assert(rsock);
895
896 /* Set the network sequence index if not set. */
897 if (consumer->net_seq_index == (uint64_t) -1ULL) {
898 pthread_mutex_lock(&relayd_net_seq_idx_lock);
899 /*
900 * Increment net_seq_idx because we are about to transfer the
901 * new relayd socket to the consumer.
902 * Assign unique key so the consumer can match streams.
903 */
904 consumer->net_seq_index = ++relayd_net_seq_idx;
905 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
906 }
907
908 /* Send relayd socket to consumer. */
909 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
910 relayd_uri->stype, session_id,
911 session_name, hostname, session_live_timer);
912 if (ret < 0) {
913 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
914 goto close_sock;
915 }
916
917 /* Flag that the corresponding socket was sent. */
918 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
919 consumer_sock->control_sock_sent = 1;
920 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
921 consumer_sock->data_sock_sent = 1;
922 }
923
924 ret = LTTNG_OK;
925
926 /*
927 * Close socket which was dup on the consumer side. The session daemon does
928 * NOT keep track of the relayd socket(s) once transfer to the consumer.
929 */
930
931 close_sock:
932 (void) relayd_close(rsock);
933 free(rsock);
934
935 error:
936 if (ret != LTTNG_OK) {
937 /*
938 * The consumer output for this session should not be used anymore
939 * since the relayd connection failed thus making any tracing or/and
940 * streaming not usable.
941 */
942 consumer->enabled = 0;
943 }
944 return ret;
945 }
946
947 /*
948 * Send both relayd sockets to a specific consumer and domain. This is a
949 * helper function to facilitate sending the information to the consumer for a
950 * session.
951 */
952 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
953 unsigned int session_id, struct consumer_output *consumer,
954 struct consumer_socket *sock, char *session_name,
955 char *hostname, int session_live_timer)
956 {
957 int ret = LTTNG_OK;
958
959 assert(consumer);
960 assert(sock);
961
962 /* Sending control relayd socket. */
963 if (!sock->control_sock_sent) {
964 ret = send_consumer_relayd_socket(domain, session_id,
965 &consumer->dst.net.control, consumer, sock,
966 session_name, hostname, session_live_timer);
967 if (ret != LTTNG_OK) {
968 goto error;
969 }
970 }
971
972 /* Sending data relayd socket. */
973 if (!sock->data_sock_sent) {
974 ret = send_consumer_relayd_socket(domain, session_id,
975 &consumer->dst.net.data, consumer, sock,
976 session_name, hostname, session_live_timer);
977 if (ret != LTTNG_OK) {
978 goto error;
979 }
980 }
981
982 error:
983 return ret;
984 }
985
986 /*
987 * Setup relayd connections for a tracing session. First creates the socket to
988 * the relayd and send them to the right domain consumer. Consumer type MUST be
989 * network.
990 */
991 int cmd_setup_relayd(struct ltt_session *session)
992 {
993 int ret = LTTNG_OK;
994 struct ltt_ust_session *usess;
995 struct ltt_kernel_session *ksess;
996 struct consumer_socket *socket;
997 struct lttng_ht_iter iter;
998
999 assert(session);
1000
1001 usess = session->ust_session;
1002 ksess = session->kernel_session;
1003
1004 DBG("Setting relayd for session %s", session->name);
1005
1006 rcu_read_lock();
1007
1008 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1009 && usess->consumer->enabled) {
1010 /* For each consumer socket, send relayd sockets */
1011 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1012 socket, node.node) {
1013 pthread_mutex_lock(socket->lock);
1014 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1015 usess->consumer, socket,
1016 session->name, session->hostname,
1017 session->live_timer);
1018 pthread_mutex_unlock(socket->lock);
1019 if (ret != LTTNG_OK) {
1020 goto error;
1021 }
1022 /* Session is now ready for network streaming. */
1023 session->net_handle = 1;
1024 }
1025 session->consumer->relay_major_version =
1026 usess->consumer->relay_major_version;
1027 session->consumer->relay_minor_version =
1028 usess->consumer->relay_minor_version;
1029 }
1030
1031 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1032 && ksess->consumer->enabled) {
1033 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1034 socket, node.node) {
1035 pthread_mutex_lock(socket->lock);
1036 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1037 ksess->consumer, socket,
1038 session->name, session->hostname,
1039 session->live_timer);
1040 pthread_mutex_unlock(socket->lock);
1041 if (ret != LTTNG_OK) {
1042 goto error;
1043 }
1044 /* Session is now ready for network streaming. */
1045 session->net_handle = 1;
1046 }
1047 session->consumer->relay_major_version =
1048 ksess->consumer->relay_major_version;
1049 session->consumer->relay_minor_version =
1050 ksess->consumer->relay_minor_version;
1051 }
1052
1053 error:
1054 rcu_read_unlock();
1055 return ret;
1056 }
1057
1058 /*
1059 * Start a kernel session by opening all necessary streams.
1060 */
1061 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1062 {
1063 int ret;
1064 struct ltt_kernel_channel *kchan;
1065
1066 /* Open kernel metadata */
1067 if (ksess->metadata == NULL && ksess->output_traces) {
1068 ret = kernel_open_metadata(ksess);
1069 if (ret < 0) {
1070 ret = LTTNG_ERR_KERN_META_FAIL;
1071 goto error;
1072 }
1073 }
1074
1075 /* Open kernel metadata stream */
1076 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1077 ret = kernel_open_metadata_stream(ksess);
1078 if (ret < 0) {
1079 ERR("Kernel create metadata stream failed");
1080 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1081 goto error;
1082 }
1083 }
1084
1085 /* For each channel */
1086 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1087 if (kchan->stream_count == 0) {
1088 ret = kernel_open_channel_stream(kchan);
1089 if (ret < 0) {
1090 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1091 goto error;
1092 }
1093 /* Update the stream global counter */
1094 ksess->stream_count_global += ret;
1095 }
1096 }
1097
1098 /* Setup kernel consumer socket and send fds to it */
1099 ret = init_kernel_tracing(ksess);
1100 if (ret != 0) {
1101 ret = LTTNG_ERR_KERN_START_FAIL;
1102 goto error;
1103 }
1104
1105 /* This start the kernel tracing */
1106 ret = kernel_start_session(ksess);
1107 if (ret < 0) {
1108 ret = LTTNG_ERR_KERN_START_FAIL;
1109 goto error;
1110 }
1111
1112 /* Quiescent wait after starting trace */
1113 kernel_wait_quiescent(kernel_tracer_fd);
1114
1115 ksess->active = 1;
1116
1117 ret = LTTNG_OK;
1118
1119 error:
1120 return ret;
1121 }
1122
1123 /*
1124 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1125 */
1126 int cmd_disable_channel(struct ltt_session *session,
1127 enum lttng_domain_type domain, char *channel_name)
1128 {
1129 int ret;
1130 struct ltt_ust_session *usess;
1131
1132 usess = session->ust_session;
1133
1134 rcu_read_lock();
1135
1136 switch (domain) {
1137 case LTTNG_DOMAIN_KERNEL:
1138 {
1139 ret = channel_kernel_disable(session->kernel_session,
1140 channel_name);
1141 if (ret != LTTNG_OK) {
1142 goto error;
1143 }
1144
1145 kernel_wait_quiescent(kernel_tracer_fd);
1146 break;
1147 }
1148 case LTTNG_DOMAIN_UST:
1149 {
1150 struct ltt_ust_channel *uchan;
1151 struct lttng_ht *chan_ht;
1152
1153 chan_ht = usess->domain_global.channels;
1154
1155 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1156 if (uchan == NULL) {
1157 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1158 goto error;
1159 }
1160
1161 ret = channel_ust_disable(usess, uchan);
1162 if (ret != LTTNG_OK) {
1163 goto error;
1164 }
1165 break;
1166 }
1167 default:
1168 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1169 goto error;
1170 }
1171
1172 ret = LTTNG_OK;
1173
1174 error:
1175 rcu_read_unlock();
1176 return ret;
1177 }
1178
1179 /*
1180 * Command LTTNG_TRACK_PID processed by the client thread.
1181 *
1182 * Called with session lock held.
1183 */
1184 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1185 int pid)
1186 {
1187 int ret;
1188
1189 rcu_read_lock();
1190
1191 switch (domain) {
1192 case LTTNG_DOMAIN_KERNEL:
1193 {
1194 struct ltt_kernel_session *ksess;
1195
1196 ksess = session->kernel_session;
1197
1198 ret = kernel_track_pid(ksess, pid);
1199 if (ret != LTTNG_OK) {
1200 goto error;
1201 }
1202
1203 kernel_wait_quiescent(kernel_tracer_fd);
1204 break;
1205 }
1206 case LTTNG_DOMAIN_UST:
1207 {
1208 struct ltt_ust_session *usess;
1209
1210 usess = session->ust_session;
1211
1212 ret = trace_ust_track_pid(usess, pid);
1213 if (ret != LTTNG_OK) {
1214 goto error;
1215 }
1216 break;
1217 }
1218 default:
1219 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1220 goto error;
1221 }
1222
1223 ret = LTTNG_OK;
1224
1225 error:
1226 rcu_read_unlock();
1227 return ret;
1228 }
1229
1230 /*
1231 * Command LTTNG_UNTRACK_PID processed by the client thread.
1232 *
1233 * Called with session lock held.
1234 */
1235 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1236 int pid)
1237 {
1238 int ret;
1239
1240 rcu_read_lock();
1241
1242 switch (domain) {
1243 case LTTNG_DOMAIN_KERNEL:
1244 {
1245 struct ltt_kernel_session *ksess;
1246
1247 ksess = session->kernel_session;
1248
1249 ret = kernel_untrack_pid(ksess, pid);
1250 if (ret != LTTNG_OK) {
1251 goto error;
1252 }
1253
1254 kernel_wait_quiescent(kernel_tracer_fd);
1255 break;
1256 }
1257 case LTTNG_DOMAIN_UST:
1258 {
1259 struct ltt_ust_session *usess;
1260
1261 usess = session->ust_session;
1262
1263 ret = trace_ust_untrack_pid(usess, pid);
1264 if (ret != LTTNG_OK) {
1265 goto error;
1266 }
1267 break;
1268 }
1269 default:
1270 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1271 goto error;
1272 }
1273
1274 ret = LTTNG_OK;
1275
1276 error:
1277 rcu_read_unlock();
1278 return ret;
1279 }
1280
1281 /*
1282 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1283 *
1284 * The wpipe arguments is used as a notifier for the kernel thread.
1285 */
1286 int cmd_enable_channel(struct ltt_session *session,
1287 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1288 {
1289 int ret;
1290 struct ltt_ust_session *usess = session->ust_session;
1291 struct lttng_ht *chan_ht;
1292 size_t len;
1293
1294 assert(session);
1295 assert(attr);
1296 assert(domain);
1297
1298 len = lttng_strnlen(attr->name, sizeof(attr->name));
1299
1300 /* Validate channel name */
1301 if (attr->name[0] == '.' ||
1302 memchr(attr->name, '/', len) != NULL) {
1303 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1304 goto end;
1305 }
1306
1307 DBG("Enabling channel %s for session %s", attr->name, session->name);
1308
1309 rcu_read_lock();
1310
1311 /*
1312 * Don't try to enable a channel if the session has been started at
1313 * some point in time before. The tracer does not allow it.
1314 */
1315 if (session->has_been_started) {
1316 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1317 goto error;
1318 }
1319
1320 /*
1321 * If the session is a live session, remove the switch timer, the
1322 * live timer does the same thing but sends also synchronisation
1323 * beacons for inactive streams.
1324 */
1325 if (session->live_timer > 0) {
1326 attr->attr.live_timer_interval = session->live_timer;
1327 attr->attr.switch_timer_interval = 0;
1328 }
1329
1330 /*
1331 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1332 * mode and with less than 2 subbuf so block it right away and send back an
1333 * invalid attribute error.
1334 */
1335 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1336 ret = LTTNG_ERR_INVALID;
1337 goto error;
1338 }
1339
1340 switch (domain->type) {
1341 case LTTNG_DOMAIN_KERNEL:
1342 {
1343 struct ltt_kernel_channel *kchan;
1344
1345 kchan = trace_kernel_get_channel_by_name(attr->name,
1346 session->kernel_session);
1347 if (kchan == NULL) {
1348 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1349 if (attr->name[0] != '\0') {
1350 session->kernel_session->has_non_default_channel = 1;
1351 }
1352 } else {
1353 ret = channel_kernel_enable(session->kernel_session, kchan);
1354 }
1355
1356 if (ret != LTTNG_OK) {
1357 goto error;
1358 }
1359
1360 kernel_wait_quiescent(kernel_tracer_fd);
1361 break;
1362 }
1363 case LTTNG_DOMAIN_UST:
1364 case LTTNG_DOMAIN_JUL:
1365 case LTTNG_DOMAIN_LOG4J:
1366 case LTTNG_DOMAIN_PYTHON:
1367 {
1368 struct ltt_ust_channel *uchan;
1369
1370 /*
1371 * FIXME
1372 *
1373 * Current agent implementation limitations force us to allow
1374 * only one channel at once in "agent" subdomains. Each
1375 * subdomain has a default channel name which must be strictly
1376 * adhered to.
1377 */
1378 if (domain->type == LTTNG_DOMAIN_JUL) {
1379 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1380 LTTNG_SYMBOL_NAME_LEN)) {
1381 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1382 goto error;
1383 }
1384 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1385 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1386 LTTNG_SYMBOL_NAME_LEN)) {
1387 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1388 goto error;
1389 }
1390 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1391 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1392 LTTNG_SYMBOL_NAME_LEN)) {
1393 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1394 goto error;
1395 }
1396 }
1397
1398 chan_ht = usess->domain_global.channels;
1399
1400 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1401 if (uchan == NULL) {
1402 ret = channel_ust_create(usess, attr, domain->buf_type);
1403 if (attr->name[0] != '\0') {
1404 usess->has_non_default_channel = 1;
1405 }
1406 } else {
1407 ret = channel_ust_enable(usess, uchan);
1408 }
1409 break;
1410 }
1411 default:
1412 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1413 goto error;
1414 }
1415
1416 error:
1417 rcu_read_unlock();
1418 end:
1419 return ret;
1420 }
1421
1422 /*
1423 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1424 */
1425 int cmd_disable_event(struct ltt_session *session,
1426 enum lttng_domain_type domain, char *channel_name,
1427 struct lttng_event *event)
1428 {
1429 int ret;
1430 char *event_name;
1431
1432 DBG("Disable event command for event \'%s\'", event->name);
1433
1434 event_name = event->name;
1435 if (validate_event_name(event_name)) {
1436 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1437 goto error;
1438 }
1439
1440 /* Error out on unhandled search criteria */
1441 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1442 || event->pid || event->filter || event->exclusion) {
1443 ret = LTTNG_ERR_UNK;
1444 goto error;
1445 }
1446
1447 rcu_read_lock();
1448
1449 switch (domain) {
1450 case LTTNG_DOMAIN_KERNEL:
1451 {
1452 struct ltt_kernel_channel *kchan;
1453 struct ltt_kernel_session *ksess;
1454
1455 ksess = session->kernel_session;
1456
1457 /*
1458 * If a non-default channel has been created in the
1459 * session, explicitely require that -c chan_name needs
1460 * to be provided.
1461 */
1462 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1463 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1464 goto error_unlock;
1465 }
1466
1467 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1468 if (kchan == NULL) {
1469 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1470 goto error_unlock;
1471 }
1472
1473 switch (event->type) {
1474 case LTTNG_EVENT_ALL:
1475 case LTTNG_EVENT_TRACEPOINT:
1476 case LTTNG_EVENT_SYSCALL:
1477 case LTTNG_EVENT_PROBE:
1478 case LTTNG_EVENT_FUNCTION:
1479 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1480 if (event_name[0] == '\0') {
1481 ret = event_kernel_disable_event(kchan,
1482 NULL, event->type);
1483 } else {
1484 ret = event_kernel_disable_event(kchan,
1485 event_name, event->type);
1486 }
1487 if (ret != LTTNG_OK) {
1488 goto error_unlock;
1489 }
1490 break;
1491 default:
1492 ret = LTTNG_ERR_UNK;
1493 goto error_unlock;
1494 }
1495
1496 kernel_wait_quiescent(kernel_tracer_fd);
1497 break;
1498 }
1499 case LTTNG_DOMAIN_UST:
1500 {
1501 struct ltt_ust_channel *uchan;
1502 struct ltt_ust_session *usess;
1503
1504 usess = session->ust_session;
1505
1506 if (validate_ust_event_name(event_name)) {
1507 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1508 goto error_unlock;
1509 }
1510
1511 /*
1512 * If a non-default channel has been created in the
1513 * session, explicitly require that -c chan_name needs
1514 * to be provided.
1515 */
1516 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1517 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1518 goto error_unlock;
1519 }
1520
1521 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1522 channel_name);
1523 if (uchan == NULL) {
1524 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1525 goto error_unlock;
1526 }
1527
1528 switch (event->type) {
1529 case LTTNG_EVENT_ALL:
1530 /*
1531 * An empty event name means that everything
1532 * should be disabled.
1533 */
1534 if (event->name[0] == '\0') {
1535 ret = event_ust_disable_all_tracepoints(usess, uchan);
1536 } else {
1537 ret = event_ust_disable_tracepoint(usess, uchan,
1538 event_name);
1539 }
1540 if (ret != LTTNG_OK) {
1541 goto error_unlock;
1542 }
1543 break;
1544 default:
1545 ret = LTTNG_ERR_UNK;
1546 goto error_unlock;
1547 }
1548
1549 DBG3("Disable UST event %s in channel %s completed", event_name,
1550 channel_name);
1551 break;
1552 }
1553 case LTTNG_DOMAIN_LOG4J:
1554 case LTTNG_DOMAIN_JUL:
1555 case LTTNG_DOMAIN_PYTHON:
1556 {
1557 struct agent *agt;
1558 struct ltt_ust_session *usess = session->ust_session;
1559
1560 assert(usess);
1561
1562 switch (event->type) {
1563 case LTTNG_EVENT_ALL:
1564 break;
1565 default:
1566 ret = LTTNG_ERR_UNK;
1567 goto error_unlock;
1568 }
1569
1570 agt = trace_ust_find_agent(usess, domain);
1571 if (!agt) {
1572 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1573 goto error_unlock;
1574 }
1575 /*
1576 * An empty event name means that everything
1577 * should be disabled.
1578 */
1579 if (event->name[0] == '\0') {
1580 ret = event_agent_disable_all(usess, agt);
1581 } else {
1582 ret = event_agent_disable(usess, agt, event_name);
1583 }
1584 if (ret != LTTNG_OK) {
1585 goto error_unlock;
1586 }
1587
1588 break;
1589 }
1590 default:
1591 ret = LTTNG_ERR_UND;
1592 goto error_unlock;
1593 }
1594
1595 ret = LTTNG_OK;
1596
1597 error_unlock:
1598 rcu_read_unlock();
1599 error:
1600 return ret;
1601 }
1602
1603 /*
1604 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1605 */
1606 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1607 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1608 {
1609 int ret, chan_kern_created = 0, chan_ust_created = 0;
1610 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1611
1612 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1613 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1614 app_ctx_name = ctx->u.app_ctx.ctx_name;
1615 }
1616
1617 switch (domain) {
1618 case LTTNG_DOMAIN_KERNEL:
1619 assert(session->kernel_session);
1620
1621 if (session->kernel_session->channel_count == 0) {
1622 /* Create default channel */
1623 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1624 if (ret != LTTNG_OK) {
1625 goto error;
1626 }
1627 chan_kern_created = 1;
1628 }
1629 /* Add kernel context to kernel tracer */
1630 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1631 if (ret != LTTNG_OK) {
1632 goto error;
1633 }
1634 break;
1635 case LTTNG_DOMAIN_JUL:
1636 case LTTNG_DOMAIN_LOG4J:
1637 {
1638 /*
1639 * Validate channel name.
1640 * If no channel name is given and the domain is JUL or LOG4J,
1641 * set it to the appropriate domain-specific channel name. If
1642 * a name is provided but does not match the expexted channel
1643 * name, return an error.
1644 */
1645 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1646 strcmp(channel_name,
1647 DEFAULT_JUL_CHANNEL_NAME)) {
1648 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1649 goto error;
1650 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1651 strcmp(channel_name,
1652 DEFAULT_LOG4J_CHANNEL_NAME)) {
1653 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1654 goto error;
1655 }
1656 /* break is _not_ missing here. */
1657 }
1658 case LTTNG_DOMAIN_UST:
1659 {
1660 struct ltt_ust_session *usess = session->ust_session;
1661 unsigned int chan_count;
1662
1663 assert(usess);
1664
1665 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1666 if (chan_count == 0) {
1667 struct lttng_channel *attr;
1668 /* Create default channel */
1669 attr = channel_new_default_attr(domain, usess->buffer_type);
1670 if (attr == NULL) {
1671 ret = LTTNG_ERR_FATAL;
1672 goto error;
1673 }
1674
1675 ret = channel_ust_create(usess, attr, usess->buffer_type);
1676 if (ret != LTTNG_OK) {
1677 free(attr);
1678 goto error;
1679 }
1680 free(attr);
1681 chan_ust_created = 1;
1682 }
1683
1684 ret = context_ust_add(usess, domain, ctx, channel_name);
1685 free(app_ctx_provider_name);
1686 free(app_ctx_name);
1687 app_ctx_name = NULL;
1688 app_ctx_provider_name = NULL;
1689 if (ret != LTTNG_OK) {
1690 goto error;
1691 }
1692 break;
1693 }
1694 default:
1695 ret = LTTNG_ERR_UND;
1696 goto error;
1697 }
1698
1699 ret = LTTNG_OK;
1700 goto end;
1701
1702 error:
1703 if (chan_kern_created) {
1704 struct ltt_kernel_channel *kchan =
1705 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1706 session->kernel_session);
1707 /* Created previously, this should NOT fail. */
1708 assert(kchan);
1709 kernel_destroy_channel(kchan);
1710 }
1711
1712 if (chan_ust_created) {
1713 struct ltt_ust_channel *uchan =
1714 trace_ust_find_channel_by_name(
1715 session->ust_session->domain_global.channels,
1716 DEFAULT_CHANNEL_NAME);
1717 /* Created previously, this should NOT fail. */
1718 assert(uchan);
1719 /* Remove from the channel list of the session. */
1720 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1721 uchan);
1722 trace_ust_destroy_channel(uchan);
1723 }
1724 end:
1725 free(app_ctx_provider_name);
1726 free(app_ctx_name);
1727 return ret;
1728 }
1729
1730 static int validate_event_name(const char *name)
1731 {
1732 int ret = 0;
1733 const char *c = name;
1734 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1735 bool null_terminated = false;
1736
1737 /*
1738 * Make sure that unescaped wildcards are only used as the last
1739 * character of the event name.
1740 */
1741 while (c < event_name_end) {
1742 switch (*c) {
1743 case '\0':
1744 null_terminated = true;
1745 goto end;
1746 case '\\':
1747 c++;
1748 break;
1749 case '*':
1750 if ((c + 1) < event_name_end && *(c + 1)) {
1751 /* Wildcard is not the last character */
1752 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1753 goto end;
1754 }
1755 default:
1756 break;
1757 }
1758 c++;
1759 }
1760 end:
1761 if (!ret && !null_terminated) {
1762 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1763 }
1764 return ret;
1765 }
1766
1767 static inline bool name_starts_with(const char *name, const char *prefix)
1768 {
1769 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1770
1771 return !strncmp(name, prefix, max_cmp_len);
1772 }
1773
1774 /* Perform userspace-specific event name validation */
1775 static int validate_ust_event_name(const char *name)
1776 {
1777 int ret = 0;
1778
1779 if (!name) {
1780 ret = -1;
1781 goto end;
1782 }
1783
1784 /*
1785 * Check name against all internal UST event component namespaces used
1786 * by the agents.
1787 */
1788 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1789 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1790 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1791 ret = -1;
1792 }
1793
1794 end:
1795 return ret;
1796 }
1797
1798 /*
1799 * Internal version of cmd_enable_event() with a supplemental
1800 * "internal_event" flag which is used to enable internal events which should
1801 * be hidden from clients. Such events are used in the agent implementation to
1802 * enable the events through which all "agent" events are funeled.
1803 */
1804 static int _cmd_enable_event(struct ltt_session *session,
1805 struct lttng_domain *domain,
1806 char *channel_name, struct lttng_event *event,
1807 char *filter_expression,
1808 struct lttng_filter_bytecode *filter,
1809 struct lttng_event_exclusion *exclusion,
1810 int wpipe, bool internal_event)
1811 {
1812 int ret, channel_created = 0;
1813 struct lttng_channel *attr = NULL;
1814
1815 assert(session);
1816 assert(event);
1817 assert(channel_name);
1818
1819 /* If we have a filter, we must have its filter expression */
1820 assert(!(!!filter_expression ^ !!filter));
1821
1822 DBG("Enable event command for event \'%s\'", event->name);
1823
1824 rcu_read_lock();
1825
1826 ret = validate_event_name(event->name);
1827 if (ret) {
1828 goto error;
1829 }
1830
1831 switch (domain->type) {
1832 case LTTNG_DOMAIN_KERNEL:
1833 {
1834 struct ltt_kernel_channel *kchan;
1835
1836 /*
1837 * If a non-default channel has been created in the
1838 * session, explicitely require that -c chan_name needs
1839 * to be provided.
1840 */
1841 if (session->kernel_session->has_non_default_channel
1842 && channel_name[0] == '\0') {
1843 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1844 goto error;
1845 }
1846
1847 kchan = trace_kernel_get_channel_by_name(channel_name,
1848 session->kernel_session);
1849 if (kchan == NULL) {
1850 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1851 LTTNG_BUFFER_GLOBAL);
1852 if (attr == NULL) {
1853 ret = LTTNG_ERR_FATAL;
1854 goto error;
1855 }
1856 if (lttng_strncpy(attr->name, channel_name,
1857 sizeof(attr->name))) {
1858 ret = LTTNG_ERR_INVALID;
1859 goto error;
1860 }
1861
1862 ret = cmd_enable_channel(session, domain, attr, wpipe);
1863 if (ret != LTTNG_OK) {
1864 goto error;
1865 }
1866 channel_created = 1;
1867 }
1868
1869 /* Get the newly created kernel channel pointer */
1870 kchan = trace_kernel_get_channel_by_name(channel_name,
1871 session->kernel_session);
1872 if (kchan == NULL) {
1873 /* This sould not happen... */
1874 ret = LTTNG_ERR_FATAL;
1875 goto error;
1876 }
1877
1878 switch (event->type) {
1879 case LTTNG_EVENT_ALL:
1880 {
1881 char *filter_expression_a = NULL;
1882 struct lttng_filter_bytecode *filter_a = NULL;
1883
1884 /*
1885 * We need to duplicate filter_expression and filter,
1886 * because ownership is passed to first enable
1887 * event.
1888 */
1889 if (filter_expression) {
1890 filter_expression_a = strdup(filter_expression);
1891 if (!filter_expression_a) {
1892 ret = LTTNG_ERR_FATAL;
1893 goto error;
1894 }
1895 }
1896 if (filter) {
1897 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1898 if (!filter_a) {
1899 free(filter_expression_a);
1900 ret = LTTNG_ERR_FATAL;
1901 goto error;
1902 }
1903 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1904 }
1905 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1906 ret = event_kernel_enable_event(kchan, event,
1907 filter_expression, filter);
1908 /* We have passed ownership */
1909 filter_expression = NULL;
1910 filter = NULL;
1911 if (ret != LTTNG_OK) {
1912 if (channel_created) {
1913 /* Let's not leak a useless channel. */
1914 kernel_destroy_channel(kchan);
1915 }
1916 free(filter_expression_a);
1917 free(filter_a);
1918 goto error;
1919 }
1920 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1921 ret = event_kernel_enable_event(kchan, event,
1922 filter_expression_a, filter_a);
1923 /* We have passed ownership */
1924 filter_expression_a = NULL;
1925 filter_a = NULL;
1926 if (ret != LTTNG_OK) {
1927 goto error;
1928 }
1929 break;
1930 }
1931 case LTTNG_EVENT_PROBE:
1932 case LTTNG_EVENT_FUNCTION:
1933 case LTTNG_EVENT_FUNCTION_ENTRY:
1934 case LTTNG_EVENT_TRACEPOINT:
1935 ret = event_kernel_enable_event(kchan, event,
1936 filter_expression, filter);
1937 /* We have passed ownership */
1938 filter_expression = NULL;
1939 filter = NULL;
1940 if (ret != LTTNG_OK) {
1941 if (channel_created) {
1942 /* Let's not leak a useless channel. */
1943 kernel_destroy_channel(kchan);
1944 }
1945 goto error;
1946 }
1947 break;
1948 case LTTNG_EVENT_SYSCALL:
1949 ret = event_kernel_enable_event(kchan, event,
1950 filter_expression, filter);
1951 /* We have passed ownership */
1952 filter_expression = NULL;
1953 filter = NULL;
1954 if (ret != LTTNG_OK) {
1955 goto error;
1956 }
1957 break;
1958 default:
1959 ret = LTTNG_ERR_UNK;
1960 goto error;
1961 }
1962
1963 kernel_wait_quiescent(kernel_tracer_fd);
1964 break;
1965 }
1966 case LTTNG_DOMAIN_UST:
1967 {
1968 struct ltt_ust_channel *uchan;
1969 struct ltt_ust_session *usess = session->ust_session;
1970
1971 assert(usess);
1972
1973 /*
1974 * If a non-default channel has been created in the
1975 * session, explicitely require that -c chan_name needs
1976 * to be provided.
1977 */
1978 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1979 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1980 goto error;
1981 }
1982
1983 /* Get channel from global UST domain */
1984 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1985 channel_name);
1986 if (uchan == NULL) {
1987 /* Create default channel */
1988 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1989 usess->buffer_type);
1990 if (attr == NULL) {
1991 ret = LTTNG_ERR_FATAL;
1992 goto error;
1993 }
1994 if (lttng_strncpy(attr->name, channel_name,
1995 sizeof(attr->name))) {
1996 ret = LTTNG_ERR_INVALID;
1997 goto error;
1998 }
1999
2000 ret = cmd_enable_channel(session, domain, attr, wpipe);
2001 if (ret != LTTNG_OK) {
2002 goto error;
2003 }
2004
2005 /* Get the newly created channel reference back */
2006 uchan = trace_ust_find_channel_by_name(
2007 usess->domain_global.channels, channel_name);
2008 assert(uchan);
2009 }
2010
2011 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2012 /*
2013 * Don't allow users to add UST events to channels which
2014 * are assigned to a userspace subdomain (JUL, Log4J,
2015 * Python, etc.).
2016 */
2017 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2018 goto error;
2019 }
2020
2021 if (!internal_event) {
2022 /*
2023 * Ensure the event name is not reserved for internal
2024 * use.
2025 */
2026 ret = validate_ust_event_name(event->name);
2027 if (ret) {
2028 WARN("Userspace event name %s failed validation.",
2029 event->name ?
2030 event->name : "NULL");
2031 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2032 goto error;
2033 }
2034 }
2035
2036 /* At this point, the session and channel exist on the tracer */
2037 ret = event_ust_enable_tracepoint(usess, uchan, event,
2038 filter_expression, filter, exclusion,
2039 internal_event);
2040 /* We have passed ownership */
2041 filter_expression = NULL;
2042 filter = NULL;
2043 exclusion = NULL;
2044 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2045 goto already_enabled;
2046 } else if (ret != LTTNG_OK) {
2047 goto error;
2048 }
2049 break;
2050 }
2051 case LTTNG_DOMAIN_LOG4J:
2052 case LTTNG_DOMAIN_JUL:
2053 case LTTNG_DOMAIN_PYTHON:
2054 {
2055 const char *default_event_name, *default_chan_name;
2056 struct agent *agt;
2057 struct lttng_event uevent;
2058 struct lttng_domain tmp_dom;
2059 struct ltt_ust_session *usess = session->ust_session;
2060
2061 assert(usess);
2062
2063 agt = trace_ust_find_agent(usess, domain->type);
2064 if (!agt) {
2065 agt = agent_create(domain->type);
2066 if (!agt) {
2067 ret = LTTNG_ERR_NOMEM;
2068 goto error;
2069 }
2070 agent_add(agt, usess->agents);
2071 }
2072
2073 /* Create the default tracepoint. */
2074 memset(&uevent, 0, sizeof(uevent));
2075 uevent.type = LTTNG_EVENT_TRACEPOINT;
2076 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2077 default_event_name = event_get_default_agent_ust_name(
2078 domain->type);
2079 if (!default_event_name) {
2080 ret = LTTNG_ERR_FATAL;
2081 goto error;
2082 }
2083 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2084 uevent.name[sizeof(uevent.name) - 1] = '\0';
2085
2086 /*
2087 * The domain type is changed because we are about to enable the
2088 * default channel and event for the JUL domain that are hardcoded.
2089 * This happens in the UST domain.
2090 */
2091 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2092 tmp_dom.type = LTTNG_DOMAIN_UST;
2093
2094 switch (domain->type) {
2095 case LTTNG_DOMAIN_LOG4J:
2096 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2097 break;
2098 case LTTNG_DOMAIN_JUL:
2099 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2100 break;
2101 case LTTNG_DOMAIN_PYTHON:
2102 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2103 break;
2104 default:
2105 /* The switch/case we are in makes this impossible */
2106 assert(0);
2107 }
2108
2109 {
2110 char *filter_expression_copy = NULL;
2111 struct lttng_filter_bytecode *filter_copy = NULL;
2112
2113 if (filter) {
2114 const size_t filter_size = sizeof(
2115 struct lttng_filter_bytecode)
2116 + filter->len;
2117
2118 filter_copy = zmalloc(filter_size);
2119 if (!filter_copy) {
2120 ret = LTTNG_ERR_NOMEM;
2121 goto error;
2122 }
2123 memcpy(filter_copy, filter, filter_size);
2124
2125 filter_expression_copy =
2126 strdup(filter_expression);
2127 if (!filter_expression) {
2128 ret = LTTNG_ERR_NOMEM;
2129 }
2130
2131 if (!filter_expression_copy || !filter_copy) {
2132 free(filter_expression_copy);
2133 free(filter_copy);
2134 goto error;
2135 }
2136 }
2137
2138 ret = cmd_enable_event_internal(session, &tmp_dom,
2139 (char *) default_chan_name,
2140 &uevent, filter_expression_copy,
2141 filter_copy, NULL, wpipe);
2142 }
2143
2144 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2145 goto already_enabled;
2146 } else if (ret != LTTNG_OK) {
2147 goto error;
2148 }
2149
2150 /* The wild card * means that everything should be enabled. */
2151 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2152 ret = event_agent_enable_all(usess, agt, event, filter,
2153 filter_expression);
2154 } else {
2155 ret = event_agent_enable(usess, agt, event, filter,
2156 filter_expression);
2157 }
2158 filter = NULL;
2159 filter_expression = NULL;
2160 if (ret != LTTNG_OK) {
2161 goto error;
2162 }
2163
2164 break;
2165 }
2166 default:
2167 ret = LTTNG_ERR_UND;
2168 goto error;
2169 }
2170
2171 ret = LTTNG_OK;
2172
2173 already_enabled:
2174 error:
2175 free(filter_expression);
2176 free(filter);
2177 free(exclusion);
2178 free(attr);
2179 rcu_read_unlock();
2180 return ret;
2181 }
2182
2183 /*
2184 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2185 * We own filter, exclusion, and filter_expression.
2186 */
2187 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
2188 char *channel_name, struct lttng_event *event,
2189 char *filter_expression,
2190 struct lttng_filter_bytecode *filter,
2191 struct lttng_event_exclusion *exclusion,
2192 int wpipe)
2193 {
2194 return _cmd_enable_event(session, domain, channel_name, event,
2195 filter_expression, filter, exclusion, wpipe, false);
2196 }
2197
2198 /*
2199 * Enable an event which is internal to LTTng. An internal should
2200 * never be made visible to clients and are immune to checks such as
2201 * reserved names.
2202 */
2203 static int cmd_enable_event_internal(struct ltt_session *session,
2204 struct lttng_domain *domain,
2205 char *channel_name, struct lttng_event *event,
2206 char *filter_expression,
2207 struct lttng_filter_bytecode *filter,
2208 struct lttng_event_exclusion *exclusion,
2209 int wpipe)
2210 {
2211 return _cmd_enable_event(session, domain, channel_name, event,
2212 filter_expression, filter, exclusion, wpipe, true);
2213 }
2214
2215 /*
2216 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2217 */
2218 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2219 struct lttng_event **events)
2220 {
2221 int ret;
2222 ssize_t nb_events = 0;
2223
2224 switch (domain) {
2225 case LTTNG_DOMAIN_KERNEL:
2226 nb_events = kernel_list_events(kernel_tracer_fd, events);
2227 if (nb_events < 0) {
2228 ret = LTTNG_ERR_KERN_LIST_FAIL;
2229 goto error;
2230 }
2231 break;
2232 case LTTNG_DOMAIN_UST:
2233 nb_events = ust_app_list_events(events);
2234 if (nb_events < 0) {
2235 ret = LTTNG_ERR_UST_LIST_FAIL;
2236 goto error;
2237 }
2238 break;
2239 case LTTNG_DOMAIN_LOG4J:
2240 case LTTNG_DOMAIN_JUL:
2241 case LTTNG_DOMAIN_PYTHON:
2242 nb_events = agent_list_events(events, domain);
2243 if (nb_events < 0) {
2244 ret = LTTNG_ERR_UST_LIST_FAIL;
2245 goto error;
2246 }
2247 break;
2248 default:
2249 ret = LTTNG_ERR_UND;
2250 goto error;
2251 }
2252
2253 return nb_events;
2254
2255 error:
2256 /* Return negative value to differentiate return code */
2257 return -ret;
2258 }
2259
2260 /*
2261 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2262 */
2263 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2264 struct lttng_event_field **fields)
2265 {
2266 int ret;
2267 ssize_t nb_fields = 0;
2268
2269 switch (domain) {
2270 case LTTNG_DOMAIN_UST:
2271 nb_fields = ust_app_list_event_fields(fields);
2272 if (nb_fields < 0) {
2273 ret = LTTNG_ERR_UST_LIST_FAIL;
2274 goto error;
2275 }
2276 break;
2277 case LTTNG_DOMAIN_KERNEL:
2278 default: /* fall-through */
2279 ret = LTTNG_ERR_UND;
2280 goto error;
2281 }
2282
2283 return nb_fields;
2284
2285 error:
2286 /* Return negative value to differentiate return code */
2287 return -ret;
2288 }
2289
2290 ssize_t cmd_list_syscalls(struct lttng_event **events)
2291 {
2292 return syscall_table_list(events);
2293 }
2294
2295 /*
2296 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2297 *
2298 * Called with session lock held.
2299 */
2300 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2301 enum lttng_domain_type domain, int32_t **pids)
2302 {
2303 int ret;
2304 ssize_t nr_pids = 0;
2305
2306 switch (domain) {
2307 case LTTNG_DOMAIN_KERNEL:
2308 {
2309 struct ltt_kernel_session *ksess;
2310
2311 ksess = session->kernel_session;
2312 nr_pids = kernel_list_tracker_pids(ksess, pids);
2313 if (nr_pids < 0) {
2314 ret = LTTNG_ERR_KERN_LIST_FAIL;
2315 goto error;
2316 }
2317 break;
2318 }
2319 case LTTNG_DOMAIN_UST:
2320 {
2321 struct ltt_ust_session *usess;
2322
2323 usess = session->ust_session;
2324 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2325 if (nr_pids < 0) {
2326 ret = LTTNG_ERR_UST_LIST_FAIL;
2327 goto error;
2328 }
2329 break;
2330 }
2331 case LTTNG_DOMAIN_LOG4J:
2332 case LTTNG_DOMAIN_JUL:
2333 case LTTNG_DOMAIN_PYTHON:
2334 default:
2335 ret = LTTNG_ERR_UND;
2336 goto error;
2337 }
2338
2339 return nr_pids;
2340
2341 error:
2342 /* Return negative value to differentiate return code */
2343 return -ret;
2344 }
2345
2346 /*
2347 * Command LTTNG_START_TRACE processed by the client thread.
2348 *
2349 * Called with session mutex held.
2350 */
2351 int cmd_start_trace(struct ltt_session *session)
2352 {
2353 int ret;
2354 unsigned long nb_chan = 0;
2355 struct ltt_kernel_session *ksession;
2356 struct ltt_ust_session *usess;
2357
2358 assert(session);
2359
2360 /* Ease our life a bit ;) */
2361 ksession = session->kernel_session;
2362 usess = session->ust_session;
2363
2364 /* Is the session already started? */
2365 if (session->active) {
2366 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2367 goto error;
2368 }
2369
2370 /*
2371 * Starting a session without channel is useless since after that it's not
2372 * possible to enable channel thus inform the client.
2373 */
2374 if (usess && usess->domain_global.channels) {
2375 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2376 }
2377 if (ksession) {
2378 nb_chan += ksession->channel_count;
2379 }
2380 if (!nb_chan) {
2381 ret = LTTNG_ERR_NO_CHANNEL;
2382 goto error;
2383 }
2384
2385 /* Kernel tracing */
2386 if (ksession != NULL) {
2387 ret = start_kernel_session(ksession, kernel_tracer_fd);
2388 if (ret != LTTNG_OK) {
2389 goto error;
2390 }
2391 }
2392
2393 /* Flag session that trace should start automatically */
2394 if (usess) {
2395 /*
2396 * Even though the start trace might fail, flag this session active so
2397 * other application coming in are started by default.
2398 */
2399 usess->active = 1;
2400
2401 ret = ust_app_start_trace_all(usess);
2402 if (ret < 0) {
2403 ret = LTTNG_ERR_UST_START_FAIL;
2404 goto error;
2405 }
2406 }
2407
2408 /* Flag this after a successful start. */
2409 session->has_been_started = 1;
2410 session->active = 1;
2411
2412 ret = LTTNG_OK;
2413
2414 error:
2415 return ret;
2416 }
2417
2418 /*
2419 * Command LTTNG_STOP_TRACE processed by the client thread.
2420 */
2421 int cmd_stop_trace(struct ltt_session *session)
2422 {
2423 int ret;
2424 struct ltt_kernel_channel *kchan;
2425 struct ltt_kernel_session *ksession;
2426 struct ltt_ust_session *usess;
2427
2428 assert(session);
2429
2430 /* Short cut */
2431 ksession = session->kernel_session;
2432 usess = session->ust_session;
2433
2434 /* Session is not active. Skip everythong and inform the client. */
2435 if (!session->active) {
2436 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2437 goto error;
2438 }
2439
2440 /* Kernel tracer */
2441 if (ksession && ksession->active) {
2442 DBG("Stop kernel tracing");
2443
2444 /* Flush metadata if exist */
2445 if (ksession->metadata_stream_fd >= 0) {
2446 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2447 if (ret < 0) {
2448 ERR("Kernel metadata flush failed");
2449 }
2450 }
2451
2452 /* Flush all buffers before stopping */
2453 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2454 ret = kernel_flush_buffer(kchan);
2455 if (ret < 0) {
2456 ERR("Kernel flush buffer error");
2457 }
2458 }
2459
2460 ret = kernel_stop_session(ksession);
2461 if (ret < 0) {
2462 ret = LTTNG_ERR_KERN_STOP_FAIL;
2463 goto error;
2464 }
2465
2466 kernel_wait_quiescent(kernel_tracer_fd);
2467
2468 ksession->active = 0;
2469 }
2470
2471 if (usess && usess->active) {
2472 /*
2473 * Even though the stop trace might fail, flag this session inactive so
2474 * other application coming in are not started by default.
2475 */
2476 usess->active = 0;
2477
2478 ret = ust_app_stop_trace_all(usess);
2479 if (ret < 0) {
2480 ret = LTTNG_ERR_UST_STOP_FAIL;
2481 goto error;
2482 }
2483 }
2484
2485 /* Flag inactive after a successful stop. */
2486 session->active = 0;
2487 ret = LTTNG_OK;
2488
2489 error:
2490 return ret;
2491 }
2492
2493 /*
2494 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2495 */
2496 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2497 struct lttng_uri *uris)
2498 {
2499 int ret, i;
2500 struct ltt_kernel_session *ksess = session->kernel_session;
2501 struct ltt_ust_session *usess = session->ust_session;
2502
2503 assert(session);
2504 assert(uris);
2505 assert(nb_uri > 0);
2506
2507 /* Can't set consumer URI if the session is active. */
2508 if (session->active) {
2509 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2510 goto error;
2511 }
2512
2513 /* Set the "global" consumer URIs */
2514 for (i = 0; i < nb_uri; i++) {
2515 ret = add_uri_to_consumer(session->consumer,
2516 &uris[i], 0, session->name);
2517 if (ret != LTTNG_OK) {
2518 goto error;
2519 }
2520 }
2521
2522 /* Set UST session URIs */
2523 if (session->ust_session) {
2524 for (i = 0; i < nb_uri; i++) {
2525 ret = add_uri_to_consumer(
2526 session->ust_session->consumer,
2527 &uris[i], LTTNG_DOMAIN_UST,
2528 session->name);
2529 if (ret != LTTNG_OK) {
2530 goto error;
2531 }
2532 }
2533 }
2534
2535 /* Set kernel session URIs */
2536 if (session->kernel_session) {
2537 for (i = 0; i < nb_uri; i++) {
2538 ret = add_uri_to_consumer(
2539 session->kernel_session->consumer,
2540 &uris[i], LTTNG_DOMAIN_KERNEL,
2541 session->name);
2542 if (ret != LTTNG_OK) {
2543 goto error;
2544 }
2545 }
2546 }
2547
2548 /*
2549 * Make sure to set the session in output mode after we set URI since a
2550 * session can be created without URL (thus flagged in no output mode).
2551 */
2552 session->output_traces = 1;
2553 if (ksess) {
2554 ksess->output_traces = 1;
2555 }
2556
2557 if (usess) {
2558 usess->output_traces = 1;
2559 }
2560
2561 /* All good! */
2562 ret = LTTNG_OK;
2563
2564 error:
2565 return ret;
2566 }
2567
2568 /*
2569 * Command LTTNG_CREATE_SESSION processed by the client thread.
2570 */
2571 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2572 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2573 {
2574 int ret;
2575 struct ltt_session *session;
2576
2577 assert(name);
2578 assert(creds);
2579
2580 /*
2581 * Verify if the session already exist
2582 *
2583 * XXX: There is no need for the session lock list here since the caller
2584 * (process_client_msg) is holding it. We might want to change that so a
2585 * single command does not lock the entire session list.
2586 */
2587 session = session_find_by_name(name);
2588 if (session != NULL) {
2589 ret = LTTNG_ERR_EXIST_SESS;
2590 goto find_error;
2591 }
2592
2593 /* Create tracing session in the registry */
2594 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2595 LTTNG_SOCK_GET_GID_CRED(creds));
2596 if (ret != LTTNG_OK) {
2597 goto session_error;
2598 }
2599
2600 /*
2601 * Get the newly created session pointer back
2602 *
2603 * XXX: There is no need for the session lock list here since the caller
2604 * (process_client_msg) is holding it. We might want to change that so a
2605 * single command does not lock the entire session list.
2606 */
2607 session = session_find_by_name(name);
2608 assert(session);
2609
2610 session->live_timer = live_timer;
2611 /* Create default consumer output for the session not yet created. */
2612 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2613 if (session->consumer == NULL) {
2614 ret = LTTNG_ERR_FATAL;
2615 goto consumer_error;
2616 }
2617
2618 if (uris) {
2619 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2620 if (ret != LTTNG_OK) {
2621 goto consumer_error;
2622 }
2623 session->output_traces = 1;
2624 } else {
2625 session->output_traces = 0;
2626 DBG2("Session %s created with no output", session->name);
2627 }
2628
2629 session->consumer->enabled = 1;
2630
2631 return LTTNG_OK;
2632
2633 consumer_error:
2634 session_destroy(session);
2635 session_error:
2636 find_error:
2637 return ret;
2638 }
2639
2640 /*
2641 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2642 */
2643 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2644 size_t nb_uri, lttng_sock_cred *creds)
2645 {
2646 int ret;
2647 struct ltt_session *session;
2648 struct snapshot_output *new_output = NULL;
2649
2650 assert(name);
2651 assert(creds);
2652
2653 /*
2654 * Create session in no output mode with URIs set to NULL. The uris we've
2655 * received are for a default snapshot output if one.
2656 */
2657 ret = cmd_create_session_uri(name, NULL, 0, creds, 0);
2658 if (ret != LTTNG_OK) {
2659 goto error;
2660 }
2661
2662 /* Get the newly created session pointer back. This should NEVER fail. */
2663 session = session_find_by_name(name);
2664 assert(session);
2665
2666 /* Flag session for snapshot mode. */
2667 session->snapshot_mode = 1;
2668
2669 /* Skip snapshot output creation if no URI is given. */
2670 if (nb_uri == 0) {
2671 goto end;
2672 }
2673
2674 new_output = snapshot_output_alloc();
2675 if (!new_output) {
2676 ret = LTTNG_ERR_NOMEM;
2677 goto error_snapshot_alloc;
2678 }
2679
2680 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2681 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2682 if (ret < 0) {
2683 if (ret == -ENOMEM) {
2684 ret = LTTNG_ERR_NOMEM;
2685 } else {
2686 ret = LTTNG_ERR_INVALID;
2687 }
2688 goto error_snapshot;
2689 }
2690
2691 rcu_read_lock();
2692 snapshot_add_output(&session->snapshot, new_output);
2693 rcu_read_unlock();
2694
2695 end:
2696 return LTTNG_OK;
2697
2698 error_snapshot:
2699 snapshot_output_destroy(new_output);
2700 error_snapshot_alloc:
2701 session_destroy(session);
2702 error:
2703 return ret;
2704 }
2705
2706 /*
2707 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2708 *
2709 * Called with session lock held.
2710 */
2711 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2712 {
2713 int ret;
2714 struct ltt_ust_session *usess;
2715 struct ltt_kernel_session *ksess;
2716
2717 /* Safety net */
2718 assert(session);
2719
2720 usess = session->ust_session;
2721 ksess = session->kernel_session;
2722
2723 /* Clean kernel session teardown */
2724 kernel_destroy_session(ksess);
2725
2726 /* UST session teardown */
2727 if (usess) {
2728 /* Close any relayd session */
2729 consumer_output_send_destroy_relayd(usess->consumer);
2730
2731 /* Destroy every UST application related to this session. */
2732 ret = ust_app_destroy_trace_all(usess);
2733 if (ret) {
2734 ERR("Error in ust_app_destroy_trace_all");
2735 }
2736
2737 /* Clean up the rest. */
2738 trace_ust_destroy_session(usess);
2739 }
2740
2741 /*
2742 * Must notify the kernel thread here to update it's poll set in order to
2743 * remove the channel(s)' fd just destroyed.
2744 */
2745 ret = notify_thread_pipe(wpipe);
2746 if (ret < 0) {
2747 PERROR("write kernel poll pipe");
2748 }
2749
2750 ret = session_destroy(session);
2751
2752 return ret;
2753 }
2754
2755 /*
2756 * Command LTTNG_CALIBRATE processed by the client thread.
2757 */
2758 int cmd_calibrate(enum lttng_domain_type domain,
2759 struct lttng_calibrate *calibrate)
2760 {
2761 int ret;
2762
2763 switch (domain) {
2764 case LTTNG_DOMAIN_KERNEL:
2765 {
2766 struct lttng_kernel_calibrate kcalibrate;
2767
2768 switch (calibrate->type) {
2769 case LTTNG_CALIBRATE_FUNCTION:
2770 default:
2771 /* Default and only possible calibrate option. */
2772 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2773 break;
2774 }
2775
2776 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2777 if (ret < 0) {
2778 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2779 goto error;
2780 }
2781 break;
2782 }
2783 case LTTNG_DOMAIN_UST:
2784 {
2785 struct lttng_ust_calibrate ucalibrate;
2786
2787 switch (calibrate->type) {
2788 case LTTNG_CALIBRATE_FUNCTION:
2789 default:
2790 /* Default and only possible calibrate option. */
2791 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2792 break;
2793 }
2794
2795 ret = ust_app_calibrate_glb(&ucalibrate);
2796 if (ret < 0) {
2797 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2798 goto error;
2799 }
2800 break;
2801 }
2802 default:
2803 ret = LTTNG_ERR_UND;
2804 goto error;
2805 }
2806
2807 ret = LTTNG_OK;
2808
2809 error:
2810 return ret;
2811 }
2812
2813 /*
2814 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2815 */
2816 int cmd_register_consumer(struct ltt_session *session,
2817 enum lttng_domain_type domain, const char *sock_path,
2818 struct consumer_data *cdata)
2819 {
2820 int ret, sock;
2821 struct consumer_socket *socket = NULL;
2822
2823 assert(session);
2824 assert(cdata);
2825 assert(sock_path);
2826
2827 switch (domain) {
2828 case LTTNG_DOMAIN_KERNEL:
2829 {
2830 struct ltt_kernel_session *ksess = session->kernel_session;
2831
2832 assert(ksess);
2833
2834 /* Can't register a consumer if there is already one */
2835 if (ksess->consumer_fds_sent != 0) {
2836 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2837 goto error;
2838 }
2839
2840 sock = lttcomm_connect_unix_sock(sock_path);
2841 if (sock < 0) {
2842 ret = LTTNG_ERR_CONNECT_FAIL;
2843 goto error;
2844 }
2845 cdata->cmd_sock = sock;
2846
2847 socket = consumer_allocate_socket(&cdata->cmd_sock);
2848 if (socket == NULL) {
2849 ret = close(sock);
2850 if (ret < 0) {
2851 PERROR("close register consumer");
2852 }
2853 cdata->cmd_sock = -1;
2854 ret = LTTNG_ERR_FATAL;
2855 goto error;
2856 }
2857
2858 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2859 if (socket->lock == NULL) {
2860 PERROR("zmalloc pthread mutex");
2861 ret = LTTNG_ERR_FATAL;
2862 goto error;
2863 }
2864 pthread_mutex_init(socket->lock, NULL);
2865 socket->registered = 1;
2866
2867 rcu_read_lock();
2868 consumer_add_socket(socket, ksess->consumer);
2869 rcu_read_unlock();
2870
2871 pthread_mutex_lock(&cdata->pid_mutex);
2872 cdata->pid = -1;
2873 pthread_mutex_unlock(&cdata->pid_mutex);
2874
2875 break;
2876 }
2877 default:
2878 /* TODO: Userspace tracing */
2879 ret = LTTNG_ERR_UND;
2880 goto error;
2881 }
2882
2883 return LTTNG_OK;
2884
2885 error:
2886 if (socket) {
2887 consumer_destroy_socket(socket);
2888 }
2889 return ret;
2890 }
2891
2892 /*
2893 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2894 */
2895 ssize_t cmd_list_domains(struct ltt_session *session,
2896 struct lttng_domain **domains)
2897 {
2898 int ret, index = 0;
2899 ssize_t nb_dom = 0;
2900 struct agent *agt;
2901 struct lttng_ht_iter iter;
2902
2903 if (session->kernel_session != NULL) {
2904 DBG3("Listing domains found kernel domain");
2905 nb_dom++;
2906 }
2907
2908 if (session->ust_session != NULL) {
2909 DBG3("Listing domains found UST global domain");
2910 nb_dom++;
2911
2912 rcu_read_lock();
2913 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2914 agt, node.node) {
2915 if (agt->being_used) {
2916 nb_dom++;
2917 }
2918 }
2919 rcu_read_unlock();
2920 }
2921
2922 if (!nb_dom) {
2923 goto end;
2924 }
2925
2926 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2927 if (*domains == NULL) {
2928 ret = LTTNG_ERR_FATAL;
2929 goto error;
2930 }
2931
2932 if (session->kernel_session != NULL) {
2933 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2934
2935 /* Kernel session buffer type is always GLOBAL */
2936 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2937
2938 index++;
2939 }
2940
2941 if (session->ust_session != NULL) {
2942 (*domains)[index].type = LTTNG_DOMAIN_UST;
2943 (*domains)[index].buf_type = session->ust_session->buffer_type;
2944 index++;
2945
2946 rcu_read_lock();
2947 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2948 agt, node.node) {
2949 if (agt->being_used) {
2950 (*domains)[index].type = agt->domain;
2951 (*domains)[index].buf_type = session->ust_session->buffer_type;
2952 index++;
2953 }
2954 }
2955 rcu_read_unlock();
2956 }
2957 end:
2958 return nb_dom;
2959
2960 error:
2961 /* Return negative value to differentiate return code */
2962 return -ret;
2963 }
2964
2965
2966 /*
2967 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2968 */
2969 ssize_t cmd_list_channels(enum lttng_domain_type domain,
2970 struct ltt_session *session, struct lttng_channel **channels)
2971 {
2972 ssize_t nb_chan = 0, payload_size = 0, ret;
2973
2974 switch (domain) {
2975 case LTTNG_DOMAIN_KERNEL:
2976 if (session->kernel_session != NULL) {
2977 nb_chan = session->kernel_session->channel_count;
2978 }
2979 DBG3("Number of kernel channels %zd", nb_chan);
2980 if (nb_chan <= 0) {
2981 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2982 goto end;
2983 }
2984 break;
2985 case LTTNG_DOMAIN_UST:
2986 if (session->ust_session != NULL) {
2987 rcu_read_lock();
2988 nb_chan = lttng_ht_get_count(
2989 session->ust_session->domain_global.channels);
2990 rcu_read_unlock();
2991 }
2992 DBG3("Number of UST global channels %zd", nb_chan);
2993 if (nb_chan < 0) {
2994 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
2995 goto end;
2996 }
2997 break;
2998 default:
2999 ret = -LTTNG_ERR_UND;
3000 goto end;
3001 }
3002
3003 if (nb_chan > 0) {
3004 const size_t channel_size = sizeof(struct lttng_channel) +
3005 sizeof(struct lttcomm_channel_extended);
3006 struct lttcomm_channel_extended *channel_exts;
3007
3008 payload_size = nb_chan * channel_size;
3009 *channels = zmalloc(payload_size);
3010 if (*channels == NULL) {
3011 ret = -LTTNG_ERR_FATAL;
3012 goto end;
3013 }
3014
3015 channel_exts = ((void *) *channels) +
3016 (nb_chan * sizeof(struct lttng_channel));
3017 list_lttng_channels(domain, session, *channels, channel_exts);
3018 } else {
3019 *channels = NULL;
3020 }
3021
3022 ret = payload_size;
3023 end:
3024 return ret;
3025 }
3026
3027 /*
3028 * Command LTTNG_LIST_EVENTS processed by the client thread.
3029 */
3030 ssize_t cmd_list_events(enum lttng_domain_type domain,
3031 struct ltt_session *session, char *channel_name,
3032 struct lttng_event **events, size_t *total_size)
3033 {
3034 int ret = 0;
3035 ssize_t nb_event = 0;
3036
3037 switch (domain) {
3038 case LTTNG_DOMAIN_KERNEL:
3039 if (session->kernel_session != NULL) {
3040 nb_event = list_lttng_kernel_events(channel_name,
3041 session->kernel_session, events,
3042 total_size);
3043 }
3044 break;
3045 case LTTNG_DOMAIN_UST:
3046 {
3047 if (session->ust_session != NULL) {
3048 nb_event = list_lttng_ust_global_events(channel_name,
3049 &session->ust_session->domain_global, events,
3050 total_size);
3051 }
3052 break;
3053 }
3054 case LTTNG_DOMAIN_LOG4J:
3055 case LTTNG_DOMAIN_JUL:
3056 case LTTNG_DOMAIN_PYTHON:
3057 if (session->ust_session) {
3058 struct lttng_ht_iter iter;
3059 struct agent *agt;
3060
3061 rcu_read_lock();
3062 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3063 &iter.iter, agt, node.node) {
3064 if (agt->domain == domain) {
3065 nb_event = list_lttng_agent_events(
3066 agt, events,
3067 total_size);
3068 break;
3069 }
3070 }
3071 rcu_read_unlock();
3072 }
3073 break;
3074 default:
3075 ret = LTTNG_ERR_UND;
3076 goto error;
3077 }
3078
3079 return nb_event;
3080
3081 error:
3082 /* Return negative value to differentiate return code */
3083 return -ret;
3084 }
3085
3086 /*
3087 * Using the session list, filled a lttng_session array to send back to the
3088 * client for session listing.
3089 *
3090 * The session list lock MUST be acquired before calling this function. Use
3091 * session_lock_list() and session_unlock_list().
3092 */
3093 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
3094 gid_t gid)
3095 {
3096 int ret;
3097 unsigned int i = 0;
3098 struct ltt_session *session;
3099 struct ltt_session_list *list = session_get_list();
3100
3101 DBG("Getting all available session for UID %d GID %d",
3102 uid, gid);
3103 /*
3104 * Iterate over session list and append data after the control struct in
3105 * the buffer.
3106 */
3107 cds_list_for_each_entry(session, &list->head, list) {
3108 /*
3109 * Only list the sessions the user can control.
3110 */
3111 if (!session_access_ok(session, uid, gid)) {
3112 continue;
3113 }
3114
3115 struct ltt_kernel_session *ksess = session->kernel_session;
3116 struct ltt_ust_session *usess = session->ust_session;
3117
3118 if (session->consumer->type == CONSUMER_DST_NET ||
3119 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3120 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3121 ret = build_network_session_path(sessions[i].path,
3122 sizeof(sessions[i].path), session);
3123 } else {
3124 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3125 session->consumer->dst.trace_path);
3126 }
3127 if (ret < 0) {
3128 PERROR("snprintf session path");
3129 continue;
3130 }
3131
3132 strncpy(sessions[i].name, session->name, NAME_MAX);
3133 sessions[i].name[NAME_MAX - 1] = '\0';
3134 sessions[i].enabled = session->active;
3135 sessions[i].snapshot_mode = session->snapshot_mode;
3136 sessions[i].live_timer_interval = session->live_timer;
3137 i++;
3138 }
3139 }
3140
3141 /*
3142 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3143 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3144 */
3145 int cmd_data_pending(struct ltt_session *session)
3146 {
3147 int ret;
3148 struct ltt_kernel_session *ksess = session->kernel_session;
3149 struct ltt_ust_session *usess = session->ust_session;
3150
3151 assert(session);
3152
3153 /* Session MUST be stopped to ask for data availability. */
3154 if (session->active) {
3155 ret = LTTNG_ERR_SESSION_STARTED;
3156 goto error;
3157 } else {
3158 /*
3159 * If stopped, just make sure we've started before else the above call
3160 * will always send that there is data pending.
3161 *
3162 * The consumer assumes that when the data pending command is received,
3163 * the trace has been started before or else no output data is written
3164 * by the streams which is a condition for data pending. So, this is
3165 * *VERY* important that we don't ask the consumer before a start
3166 * trace.
3167 */
3168 if (!session->has_been_started) {
3169 ret = 0;
3170 goto error;
3171 }
3172 }
3173
3174 if (ksess && ksess->consumer) {
3175 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3176 if (ret == 1) {
3177 /* Data is still being extracted for the kernel. */
3178 goto error;
3179 }
3180 }
3181
3182 if (usess && usess->consumer) {
3183 ret = consumer_is_data_pending(usess->id, usess->consumer);
3184 if (ret == 1) {
3185 /* Data is still being extracted for the kernel. */
3186 goto error;
3187 }
3188 }
3189
3190 /* Data is ready to be read by a viewer */
3191 ret = 0;
3192
3193 error:
3194 return ret;
3195 }
3196
3197 /*
3198 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3199 *
3200 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3201 */
3202 int cmd_snapshot_add_output(struct ltt_session *session,
3203 struct lttng_snapshot_output *output, uint32_t *id)
3204 {
3205 int ret;
3206 struct snapshot_output *new_output;
3207
3208 assert(session);
3209 assert(output);
3210
3211 DBG("Cmd snapshot add output for session %s", session->name);
3212
3213 /*
3214 * Permission denied to create an output if the session is not
3215 * set in no output mode.
3216 */
3217 if (session->output_traces) {
3218 ret = LTTNG_ERR_EPERM;
3219 goto error;
3220 }
3221
3222 /* Only one output is allowed until we have the "tee" feature. */
3223 if (session->snapshot.nb_output == 1) {
3224 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3225 goto error;
3226 }
3227
3228 new_output = snapshot_output_alloc();
3229 if (!new_output) {
3230 ret = LTTNG_ERR_NOMEM;
3231 goto error;
3232 }
3233
3234 ret = snapshot_output_init(output->max_size, output->name,
3235 output->ctrl_url, output->data_url, session->consumer, new_output,
3236 &session->snapshot);
3237 if (ret < 0) {
3238 if (ret == -ENOMEM) {
3239 ret = LTTNG_ERR_NOMEM;
3240 } else {
3241 ret = LTTNG_ERR_INVALID;
3242 }
3243 goto free_error;
3244 }
3245
3246 rcu_read_lock();
3247 snapshot_add_output(&session->snapshot, new_output);
3248 if (id) {
3249 *id = new_output->id;
3250 }
3251 rcu_read_unlock();
3252
3253 return LTTNG_OK;
3254
3255 free_error:
3256 snapshot_output_destroy(new_output);
3257 error:
3258 return ret;
3259 }
3260
3261 /*
3262 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3263 *
3264 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3265 */
3266 int cmd_snapshot_del_output(struct ltt_session *session,
3267 struct lttng_snapshot_output *output)
3268 {
3269 int ret;
3270 struct snapshot_output *sout = NULL;
3271
3272 assert(session);
3273 assert(output);
3274
3275 rcu_read_lock();
3276
3277 /*
3278 * Permission denied to create an output if the session is not