Fix: illegal memory access in add_uri_to_consumer
[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 /* Explicit length checks for strcpy and strcat. */
762 if (strlen(uri->dst.path) + strlen(default_trace_dir)
763 >= sizeof(consumer->dst.trace_path)) {
764 ret = LTTNG_ERR_FATAL;
765 goto error;
766 }
767 strcpy(consumer->dst.trace_path, uri->dst.path);
768 /* Append default trace dir */
769 strcat(consumer->dst.trace_path, default_trace_dir);
770 /* Flag consumer as local. */
771 consumer->type = CONSUMER_DST_LOCAL;
772 break;
773 }
774
775 ret = LTTNG_OK;
776
777 error:
778 return ret;
779 }
780
781 /*
782 * Init tracing by creating trace directory and sending fds kernel consumer.
783 */
784 static int init_kernel_tracing(struct ltt_kernel_session *session)
785 {
786 int ret = 0;
787 struct lttng_ht_iter iter;
788 struct consumer_socket *socket;
789
790 assert(session);
791
792 rcu_read_lock();
793
794 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
795 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
796 socket, node.node) {
797 pthread_mutex_lock(socket->lock);
798 ret = kernel_consumer_send_session(socket, session);
799 pthread_mutex_unlock(socket->lock);
800 if (ret < 0) {
801 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
802 goto error;
803 }
804 }
805 }
806
807 error:
808 rcu_read_unlock();
809 return ret;
810 }
811
812 /*
813 * Create a socket to the relayd using the URI.
814 *
815 * On success, the relayd_sock pointer is set to the created socket.
816 * Else, it's stays untouched and a lttcomm error code is returned.
817 */
818 static int create_connect_relayd(struct lttng_uri *uri,
819 struct lttcomm_relayd_sock **relayd_sock,
820 struct consumer_output *consumer)
821 {
822 int ret;
823 struct lttcomm_relayd_sock *rsock;
824
825 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
826 RELAYD_VERSION_COMM_MINOR);
827 if (!rsock) {
828 ret = LTTNG_ERR_FATAL;
829 goto error;
830 }
831
832 /*
833 * Connect to relayd so we can proceed with a session creation. This call
834 * can possibly block for an arbitrary amount of time to set the health
835 * state to be in poll execution.
836 */
837 health_poll_entry();
838 ret = relayd_connect(rsock);
839 health_poll_exit();
840 if (ret < 0) {
841 ERR("Unable to reach lttng-relayd");
842 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
843 goto free_sock;
844 }
845
846 /* Create socket for control stream. */
847 if (uri->stype == LTTNG_STREAM_CONTROL) {
848 DBG3("Creating relayd stream socket from URI");
849
850 /* Check relayd version */
851 ret = relayd_version_check(rsock);
852 if (ret < 0) {
853 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
854 goto close_sock;
855 }
856 consumer->relay_major_version = rsock->major;
857 consumer->relay_minor_version = rsock->minor;
858 } else if (uri->stype == LTTNG_STREAM_DATA) {
859 DBG3("Creating relayd data socket from URI");
860 } else {
861 /* Command is not valid */
862 ERR("Relayd invalid stream type: %d", uri->stype);
863 ret = LTTNG_ERR_INVALID;
864 goto close_sock;
865 }
866
867 *relayd_sock = rsock;
868
869 return LTTNG_OK;
870
871 close_sock:
872 /* The returned value is not useful since we are on an error path. */
873 (void) relayd_close(rsock);
874 free_sock:
875 free(rsock);
876 error:
877 return ret;
878 }
879
880 /*
881 * Connect to the relayd using URI and send the socket to the right consumer.
882 */
883 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
884 unsigned int session_id, struct lttng_uri *relayd_uri,
885 struct consumer_output *consumer,
886 struct consumer_socket *consumer_sock,
887 char *session_name, char *hostname, int session_live_timer)
888 {
889 int ret;
890 struct lttcomm_relayd_sock *rsock = NULL;
891
892 /* Connect to relayd and make version check if uri is the control. */
893 ret = create_connect_relayd(relayd_uri, &rsock, consumer);
894 if (ret != LTTNG_OK) {
895 goto error;
896 }
897 assert(rsock);
898
899 /* Set the network sequence index if not set. */
900 if (consumer->net_seq_index == (uint64_t) -1ULL) {
901 pthread_mutex_lock(&relayd_net_seq_idx_lock);
902 /*
903 * Increment net_seq_idx because we are about to transfer the
904 * new relayd socket to the consumer.
905 * Assign unique key so the consumer can match streams.
906 */
907 consumer->net_seq_index = ++relayd_net_seq_idx;
908 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
909 }
910
911 /* Send relayd socket to consumer. */
912 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
913 relayd_uri->stype, session_id,
914 session_name, hostname, session_live_timer);
915 if (ret < 0) {
916 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
917 goto close_sock;
918 }
919
920 /* Flag that the corresponding socket was sent. */
921 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
922 consumer_sock->control_sock_sent = 1;
923 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
924 consumer_sock->data_sock_sent = 1;
925 }
926
927 ret = LTTNG_OK;
928
929 /*
930 * Close socket which was dup on the consumer side. The session daemon does
931 * NOT keep track of the relayd socket(s) once transfer to the consumer.
932 */
933
934 close_sock:
935 (void) relayd_close(rsock);
936 free(rsock);
937
938 error:
939 if (ret != LTTNG_OK) {
940 /*
941 * The consumer output for this session should not be used anymore
942 * since the relayd connection failed thus making any tracing or/and
943 * streaming not usable.
944 */
945 consumer->enabled = 0;
946 }
947 return ret;
948 }
949
950 /*
951 * Send both relayd sockets to a specific consumer and domain. This is a
952 * helper function to facilitate sending the information to the consumer for a
953 * session.
954 */
955 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
956 unsigned int session_id, struct consumer_output *consumer,
957 struct consumer_socket *sock, char *session_name,
958 char *hostname, int session_live_timer)
959 {
960 int ret = LTTNG_OK;
961
962 assert(consumer);
963 assert(sock);
964
965 /* Sending control relayd socket. */
966 if (!sock->control_sock_sent) {
967 ret = send_consumer_relayd_socket(domain, session_id,
968 &consumer->dst.net.control, consumer, sock,
969 session_name, hostname, session_live_timer);
970 if (ret != LTTNG_OK) {
971 goto error;
972 }
973 }
974
975 /* Sending data relayd socket. */
976 if (!sock->data_sock_sent) {
977 ret = send_consumer_relayd_socket(domain, session_id,
978 &consumer->dst.net.data, consumer, sock,
979 session_name, hostname, session_live_timer);
980 if (ret != LTTNG_OK) {
981 goto error;
982 }
983 }
984
985 error:
986 return ret;
987 }
988
989 /*
990 * Setup relayd connections for a tracing session. First creates the socket to
991 * the relayd and send them to the right domain consumer. Consumer type MUST be
992 * network.
993 */
994 int cmd_setup_relayd(struct ltt_session *session)
995 {
996 int ret = LTTNG_OK;
997 struct ltt_ust_session *usess;
998 struct ltt_kernel_session *ksess;
999 struct consumer_socket *socket;
1000 struct lttng_ht_iter iter;
1001
1002 assert(session);
1003
1004 usess = session->ust_session;
1005 ksess = session->kernel_session;
1006
1007 DBG("Setting relayd for session %s", session->name);
1008
1009 rcu_read_lock();
1010
1011 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1012 && usess->consumer->enabled) {
1013 /* For each consumer socket, send relayd sockets */
1014 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1015 socket, node.node) {
1016 pthread_mutex_lock(socket->lock);
1017 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1018 usess->consumer, socket,
1019 session->name, session->hostname,
1020 session->live_timer);
1021 pthread_mutex_unlock(socket->lock);
1022 if (ret != LTTNG_OK) {
1023 goto error;
1024 }
1025 /* Session is now ready for network streaming. */
1026 session->net_handle = 1;
1027 }
1028 session->consumer->relay_major_version =
1029 usess->consumer->relay_major_version;
1030 session->consumer->relay_minor_version =
1031 usess->consumer->relay_minor_version;
1032 }
1033
1034 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1035 && ksess->consumer->enabled) {
1036 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1037 socket, node.node) {
1038 pthread_mutex_lock(socket->lock);
1039 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1040 ksess->consumer, socket,
1041 session->name, session->hostname,
1042 session->live_timer);
1043 pthread_mutex_unlock(socket->lock);
1044 if (ret != LTTNG_OK) {
1045 goto error;
1046 }
1047 /* Session is now ready for network streaming. */
1048 session->net_handle = 1;
1049 }
1050 session->consumer->relay_major_version =
1051 ksess->consumer->relay_major_version;
1052 session->consumer->relay_minor_version =
1053 ksess->consumer->relay_minor_version;
1054 }
1055
1056 error:
1057 rcu_read_unlock();
1058 return ret;
1059 }
1060
1061 /*
1062 * Start a kernel session by opening all necessary streams.
1063 */
1064 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1065 {
1066 int ret;
1067 struct ltt_kernel_channel *kchan;
1068
1069 /* Open kernel metadata */
1070 if (ksess->metadata == NULL && ksess->output_traces) {
1071 ret = kernel_open_metadata(ksess);
1072 if (ret < 0) {
1073 ret = LTTNG_ERR_KERN_META_FAIL;
1074 goto error;
1075 }
1076 }
1077
1078 /* Open kernel metadata stream */
1079 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1080 ret = kernel_open_metadata_stream(ksess);
1081 if (ret < 0) {
1082 ERR("Kernel create metadata stream failed");
1083 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1084 goto error;
1085 }
1086 }
1087
1088 /* For each channel */
1089 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1090 if (kchan->stream_count == 0) {
1091 ret = kernel_open_channel_stream(kchan);
1092 if (ret < 0) {
1093 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1094 goto error;
1095 }
1096 /* Update the stream global counter */
1097 ksess->stream_count_global += ret;
1098 }
1099 }
1100
1101 /* Setup kernel consumer socket and send fds to it */
1102 ret = init_kernel_tracing(ksess);
1103 if (ret != 0) {
1104 ret = LTTNG_ERR_KERN_START_FAIL;
1105 goto error;
1106 }
1107
1108 /* This start the kernel tracing */
1109 ret = kernel_start_session(ksess);
1110 if (ret < 0) {
1111 ret = LTTNG_ERR_KERN_START_FAIL;
1112 goto error;
1113 }
1114
1115 /* Quiescent wait after starting trace */
1116 kernel_wait_quiescent(kernel_tracer_fd);
1117
1118 ksess->active = 1;
1119
1120 ret = LTTNG_OK;
1121
1122 error:
1123 return ret;
1124 }
1125
1126 /*
1127 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1128 */
1129 int cmd_disable_channel(struct ltt_session *session,
1130 enum lttng_domain_type domain, char *channel_name)
1131 {
1132 int ret;
1133 struct ltt_ust_session *usess;
1134
1135 usess = session->ust_session;
1136
1137 rcu_read_lock();
1138
1139 switch (domain) {
1140 case LTTNG_DOMAIN_KERNEL:
1141 {
1142 ret = channel_kernel_disable(session->kernel_session,
1143 channel_name);
1144 if (ret != LTTNG_OK) {
1145 goto error;
1146 }
1147
1148 kernel_wait_quiescent(kernel_tracer_fd);
1149 break;
1150 }
1151 case LTTNG_DOMAIN_UST:
1152 {
1153 struct ltt_ust_channel *uchan;
1154 struct lttng_ht *chan_ht;
1155
1156 chan_ht = usess->domain_global.channels;
1157
1158 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1159 if (uchan == NULL) {
1160 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1161 goto error;
1162 }
1163
1164 ret = channel_ust_disable(usess, uchan);
1165 if (ret != LTTNG_OK) {
1166 goto error;
1167 }
1168 break;
1169 }
1170 default:
1171 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1172 goto error;
1173 }
1174
1175 ret = LTTNG_OK;
1176
1177 error:
1178 rcu_read_unlock();
1179 return ret;
1180 }
1181
1182 /*
1183 * Command LTTNG_TRACK_PID processed by the client thread.
1184 *
1185 * Called with session lock held.
1186 */
1187 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1188 int pid)
1189 {
1190 int ret;
1191
1192 rcu_read_lock();
1193
1194 switch (domain) {
1195 case LTTNG_DOMAIN_KERNEL:
1196 {
1197 struct ltt_kernel_session *ksess;
1198
1199 ksess = session->kernel_session;
1200
1201 ret = kernel_track_pid(ksess, pid);
1202 if (ret != LTTNG_OK) {
1203 goto error;
1204 }
1205
1206 kernel_wait_quiescent(kernel_tracer_fd);
1207 break;
1208 }
1209 case LTTNG_DOMAIN_UST:
1210 {
1211 struct ltt_ust_session *usess;
1212
1213 usess = session->ust_session;
1214
1215 ret = trace_ust_track_pid(usess, pid);
1216 if (ret != LTTNG_OK) {
1217 goto error;
1218 }
1219 break;
1220 }
1221 default:
1222 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1223 goto error;
1224 }
1225
1226 ret = LTTNG_OK;
1227
1228 error:
1229 rcu_read_unlock();
1230 return ret;
1231 }
1232
1233 /*
1234 * Command LTTNG_UNTRACK_PID processed by the client thread.
1235 *
1236 * Called with session lock held.
1237 */
1238 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1239 int pid)
1240 {
1241 int ret;
1242
1243 rcu_read_lock();
1244
1245 switch (domain) {
1246 case LTTNG_DOMAIN_KERNEL:
1247 {
1248 struct ltt_kernel_session *ksess;
1249
1250 ksess = session->kernel_session;
1251
1252 ret = kernel_untrack_pid(ksess, pid);
1253 if (ret != LTTNG_OK) {
1254 goto error;
1255 }
1256
1257 kernel_wait_quiescent(kernel_tracer_fd);
1258 break;
1259 }
1260 case LTTNG_DOMAIN_UST:
1261 {
1262 struct ltt_ust_session *usess;
1263
1264 usess = session->ust_session;
1265
1266 ret = trace_ust_untrack_pid(usess, pid);
1267 if (ret != LTTNG_OK) {
1268 goto error;
1269 }
1270 break;
1271 }
1272 default:
1273 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1274 goto error;
1275 }
1276
1277 ret = LTTNG_OK;
1278
1279 error:
1280 rcu_read_unlock();
1281 return ret;
1282 }
1283
1284 /*
1285 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1286 *
1287 * The wpipe arguments is used as a notifier for the kernel thread.
1288 */
1289 int cmd_enable_channel(struct ltt_session *session,
1290 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1291 {
1292 int ret;
1293 struct ltt_ust_session *usess = session->ust_session;
1294 struct lttng_ht *chan_ht;
1295 size_t len;
1296
1297 assert(session);
1298 assert(attr);
1299 assert(domain);
1300
1301 len = lttng_strnlen(attr->name, sizeof(attr->name));
1302
1303 /* Validate channel name */
1304 if (attr->name[0] == '.' ||
1305 memchr(attr->name, '/', len) != NULL) {
1306 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1307 goto end;
1308 }
1309
1310 DBG("Enabling channel %s for session %s", attr->name, session->name);
1311
1312 rcu_read_lock();
1313
1314 /*
1315 * Don't try to enable a channel if the session has been started at
1316 * some point in time before. The tracer does not allow it.
1317 */
1318 if (session->has_been_started) {
1319 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1320 goto error;
1321 }
1322
1323 /*
1324 * If the session is a live session, remove the switch timer, the
1325 * live timer does the same thing but sends also synchronisation
1326 * beacons for inactive streams.
1327 */
1328 if (session->live_timer > 0) {
1329 attr->attr.live_timer_interval = session->live_timer;
1330 attr->attr.switch_timer_interval = 0;
1331 }
1332
1333 /*
1334 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1335 * mode and with less than 2 subbuf so block it right away and send back an
1336 * invalid attribute error.
1337 */
1338 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1339 ret = LTTNG_ERR_INVALID;
1340 goto error;
1341 }
1342
1343 switch (domain->type) {
1344 case LTTNG_DOMAIN_KERNEL:
1345 {
1346 struct ltt_kernel_channel *kchan;
1347
1348 kchan = trace_kernel_get_channel_by_name(attr->name,
1349 session->kernel_session);
1350 if (kchan == NULL) {
1351 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1352 if (attr->name[0] != '\0') {
1353 session->kernel_session->has_non_default_channel = 1;
1354 }
1355 } else {
1356 ret = channel_kernel_enable(session->kernel_session, kchan);
1357 }
1358
1359 if (ret != LTTNG_OK) {
1360 goto error;
1361 }
1362
1363 kernel_wait_quiescent(kernel_tracer_fd);
1364 break;
1365 }
1366 case LTTNG_DOMAIN_UST:
1367 case LTTNG_DOMAIN_JUL:
1368 case LTTNG_DOMAIN_LOG4J:
1369 case LTTNG_DOMAIN_PYTHON:
1370 {
1371 struct ltt_ust_channel *uchan;
1372
1373 /*
1374 * FIXME
1375 *
1376 * Current agent implementation limitations force us to allow
1377 * only one channel at once in "agent" subdomains. Each
1378 * subdomain has a default channel name which must be strictly
1379 * adhered to.
1380 */
1381 if (domain->type == LTTNG_DOMAIN_JUL) {
1382 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1383 LTTNG_SYMBOL_NAME_LEN)) {
1384 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1385 goto error;
1386 }
1387 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1388 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1389 LTTNG_SYMBOL_NAME_LEN)) {
1390 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1391 goto error;
1392 }
1393 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1394 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1395 LTTNG_SYMBOL_NAME_LEN)) {
1396 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1397 goto error;
1398 }
1399 }
1400
1401 chan_ht = usess->domain_global.channels;
1402
1403 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1404 if (uchan == NULL) {
1405 ret = channel_ust_create(usess, attr, domain->buf_type);
1406 if (attr->name[0] != '\0') {
1407 usess->has_non_default_channel = 1;
1408 }
1409 } else {
1410 ret = channel_ust_enable(usess, uchan);
1411 }
1412 break;
1413 }
1414 default:
1415 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1416 goto error;
1417 }
1418
1419 error:
1420 rcu_read_unlock();
1421 end:
1422 return ret;
1423 }
1424
1425 /*
1426 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1427 */
1428 int cmd_disable_event(struct ltt_session *session,
1429 enum lttng_domain_type domain, char *channel_name,
1430 struct lttng_event *event)
1431 {
1432 int ret;
1433 char *event_name;
1434
1435 DBG("Disable event command for event \'%s\'", event->name);
1436
1437 event_name = event->name;
1438 if (validate_event_name(event_name)) {
1439 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1440 goto error;
1441 }
1442
1443 /* Error out on unhandled search criteria */
1444 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1445 || event->pid || event->filter || event->exclusion) {
1446 ret = LTTNG_ERR_UNK;
1447 goto error;
1448 }
1449
1450 rcu_read_lock();
1451
1452 switch (domain) {
1453 case LTTNG_DOMAIN_KERNEL:
1454 {
1455 struct ltt_kernel_channel *kchan;
1456 struct ltt_kernel_session *ksess;
1457
1458 ksess = session->kernel_session;
1459
1460 /*
1461 * If a non-default channel has been created in the
1462 * session, explicitely require that -c chan_name needs
1463 * to be provided.
1464 */
1465 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1466 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1467 goto error_unlock;
1468 }
1469
1470 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1471 if (kchan == NULL) {
1472 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1473 goto error_unlock;
1474 }
1475
1476 switch (event->type) {
1477 case LTTNG_EVENT_ALL:
1478 case LTTNG_EVENT_TRACEPOINT:
1479 case LTTNG_EVENT_SYSCALL:
1480 case LTTNG_EVENT_PROBE:
1481 case LTTNG_EVENT_FUNCTION:
1482 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1483 if (event_name[0] == '\0') {
1484 ret = event_kernel_disable_event(kchan,
1485 NULL, event->type);
1486 } else {
1487 ret = event_kernel_disable_event(kchan,
1488 event_name, event->type);
1489 }
1490 if (ret != LTTNG_OK) {
1491 goto error_unlock;
1492 }
1493 break;
1494 default:
1495 ret = LTTNG_ERR_UNK;
1496 goto error_unlock;
1497 }
1498
1499 kernel_wait_quiescent(kernel_tracer_fd);
1500 break;
1501 }
1502 case LTTNG_DOMAIN_UST:
1503 {
1504 struct ltt_ust_channel *uchan;
1505 struct ltt_ust_session *usess;
1506
1507 usess = session->ust_session;
1508
1509 if (validate_ust_event_name(event_name)) {
1510 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1511 goto error_unlock;
1512 }
1513
1514 /*
1515 * If a non-default channel has been created in the
1516 * session, explicitly require that -c chan_name needs
1517 * to be provided.
1518 */
1519 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1520 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1521 goto error_unlock;
1522 }
1523
1524 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1525 channel_name);
1526 if (uchan == NULL) {
1527 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1528 goto error_unlock;
1529 }
1530
1531 switch (event->type) {
1532 case LTTNG_EVENT_ALL:
1533 /*
1534 * An empty event name means that everything
1535 * should be disabled.
1536 */
1537 if (event->name[0] == '\0') {
1538 ret = event_ust_disable_all_tracepoints(usess, uchan);
1539 } else {
1540 ret = event_ust_disable_tracepoint(usess, uchan,
1541 event_name);
1542 }
1543 if (ret != LTTNG_OK) {
1544 goto error_unlock;
1545 }
1546 break;
1547 default:
1548 ret = LTTNG_ERR_UNK;
1549 goto error_unlock;
1550 }
1551
1552 DBG3("Disable UST event %s in channel %s completed", event_name,
1553 channel_name);
1554 break;
1555 }
1556 case LTTNG_DOMAIN_LOG4J:
1557 case LTTNG_DOMAIN_JUL:
1558 case LTTNG_DOMAIN_PYTHON:
1559 {
1560 struct agent *agt;
1561 struct ltt_ust_session *usess = session->ust_session;
1562
1563 assert(usess);
1564
1565 switch (event->type) {
1566 case LTTNG_EVENT_ALL:
1567 break;
1568 default:
1569 ret = LTTNG_ERR_UNK;
1570 goto error_unlock;
1571 }
1572
1573 agt = trace_ust_find_agent(usess, domain);
1574 if (!agt) {
1575 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1576 goto error_unlock;
1577 }
1578 /*
1579 * An empty event name means that everything
1580 * should be disabled.
1581 */
1582 if (event->name[0] == '\0') {
1583 ret = event_agent_disable_all(usess, agt);
1584 } else {
1585 ret = event_agent_disable(usess, agt, event_name);
1586 }
1587 if (ret != LTTNG_OK) {
1588 goto error_unlock;
1589 }
1590
1591 break;
1592 }
1593 default:
1594 ret = LTTNG_ERR_UND;
1595 goto error_unlock;
1596 }
1597
1598 ret = LTTNG_OK;
1599
1600 error_unlock:
1601 rcu_read_unlock();
1602 error:
1603 return ret;
1604 }
1605
1606 /*
1607 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1608 */
1609 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1610 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1611 {
1612 int ret, chan_kern_created = 0, chan_ust_created = 0;
1613 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1614
1615 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1616 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1617 app_ctx_name = ctx->u.app_ctx.ctx_name;
1618 }
1619
1620 switch (domain) {
1621 case LTTNG_DOMAIN_KERNEL:
1622 assert(session->kernel_session);
1623
1624 if (session->kernel_session->channel_count == 0) {
1625 /* Create default channel */
1626 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1627 if (ret != LTTNG_OK) {
1628 goto error;
1629 }
1630 chan_kern_created = 1;
1631 }
1632 /* Add kernel context to kernel tracer */
1633 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1634 if (ret != LTTNG_OK) {
1635 goto error;
1636 }
1637 break;
1638 case LTTNG_DOMAIN_JUL:
1639 case LTTNG_DOMAIN_LOG4J:
1640 {
1641 /*
1642 * Validate channel name.
1643 * If no channel name is given and the domain is JUL or LOG4J,
1644 * set it to the appropriate domain-specific channel name. If
1645 * a name is provided but does not match the expexted channel
1646 * name, return an error.
1647 */
1648 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1649 strcmp(channel_name,
1650 DEFAULT_JUL_CHANNEL_NAME)) {
1651 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1652 goto error;
1653 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1654 strcmp(channel_name,
1655 DEFAULT_LOG4J_CHANNEL_NAME)) {
1656 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1657 goto error;
1658 }
1659 /* break is _not_ missing here. */
1660 }
1661 case LTTNG_DOMAIN_UST:
1662 {
1663 struct ltt_ust_session *usess = session->ust_session;
1664 unsigned int chan_count;
1665
1666 assert(usess);
1667
1668 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1669 if (chan_count == 0) {
1670 struct lttng_channel *attr;
1671 /* Create default channel */
1672 attr = channel_new_default_attr(domain, usess->buffer_type);
1673 if (attr == NULL) {
1674 ret = LTTNG_ERR_FATAL;
1675 goto error;
1676 }
1677
1678 ret = channel_ust_create(usess, attr, usess->buffer_type);
1679 if (ret != LTTNG_OK) {
1680 free(attr);
1681 goto error;
1682 }
1683 free(attr);
1684 chan_ust_created = 1;
1685 }
1686
1687 ret = context_ust_add(usess, domain, ctx, channel_name);
1688 free(app_ctx_provider_name);
1689 free(app_ctx_name);
1690 app_ctx_name = NULL;
1691 app_ctx_provider_name = NULL;
1692 if (ret != LTTNG_OK) {
1693 goto error;
1694 }
1695 break;
1696 }
1697 default:
1698 ret = LTTNG_ERR_UND;
1699 goto error;
1700 }
1701
1702 ret = LTTNG_OK;
1703 goto end;
1704
1705 error:
1706 if (chan_kern_created) {
1707 struct ltt_kernel_channel *kchan =
1708 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1709 session->kernel_session);
1710 /* Created previously, this should NOT fail. */
1711 assert(kchan);
1712 kernel_destroy_channel(kchan);
1713 }
1714
1715 if (chan_ust_created) {
1716 struct ltt_ust_channel *uchan =
1717 trace_ust_find_channel_by_name(
1718 session->ust_session->domain_global.channels,
1719 DEFAULT_CHANNEL_NAME);
1720 /* Created previously, this should NOT fail. */
1721 assert(uchan);
1722 /* Remove from the channel list of the session. */
1723 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1724 uchan);
1725 trace_ust_destroy_channel(uchan);
1726 }
1727 end:
1728 free(app_ctx_provider_name);
1729 free(app_ctx_name);
1730 return ret;
1731 }
1732
1733 static int validate_event_name(const char *name)
1734 {
1735 int ret = 0;
1736 const char *c = name;
1737 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1738 bool null_terminated = false;
1739
1740 /*
1741 * Make sure that unescaped wildcards are only used as the last
1742 * character of the event name.
1743 */
1744 while (c < event_name_end) {
1745 switch (*c) {
1746 case '\0':
1747 null_terminated = true;
1748 goto end;
1749 case '\\':
1750 c++;
1751 break;
1752 case '*':
1753 if ((c + 1) < event_name_end && *(c + 1)) {
1754 /* Wildcard is not the last character */
1755 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1756 goto end;
1757 }
1758 default:
1759 break;
1760 }
1761 c++;
1762 }
1763 end:
1764 if (!ret && !null_terminated) {
1765 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1766 }
1767 return ret;
1768 }
1769
1770 static inline bool name_starts_with(const char *name, const char *prefix)
1771 {
1772 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1773
1774 return !strncmp(name, prefix, max_cmp_len);
1775 }
1776
1777 /* Perform userspace-specific event name validation */
1778 static int validate_ust_event_name(const char *name)
1779 {
1780 int ret = 0;
1781
1782 if (!name) {
1783 ret = -1;
1784 goto end;
1785 }
1786
1787 /*
1788 * Check name against all internal UST event component namespaces used
1789 * by the agents.
1790 */
1791 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1792 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1793 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1794 ret = -1;
1795 }
1796
1797 end:
1798 return ret;
1799 }
1800
1801 /*
1802 * Internal version of cmd_enable_event() with a supplemental
1803 * "internal_event" flag which is used to enable internal events which should
1804 * be hidden from clients. Such events are used in the agent implementation to
1805 * enable the events through which all "agent" events are funeled.
1806 */
1807 static int _cmd_enable_event(struct ltt_session *session,
1808 struct lttng_domain *domain,
1809 char *channel_name, struct lttng_event *event,
1810 char *filter_expression,
1811 struct lttng_filter_bytecode *filter,
1812 struct lttng_event_exclusion *exclusion,
1813 int wpipe, bool internal_event)
1814 {
1815 int ret, channel_created = 0;
1816 struct lttng_channel *attr = NULL;
1817
1818 assert(session);
1819 assert(event);
1820 assert(channel_name);
1821
1822 /* If we have a filter, we must have its filter expression */
1823 assert(!(!!filter_expression ^ !!filter));
1824
1825 DBG("Enable event command for event \'%s\'", event->name);
1826
1827 rcu_read_lock();
1828
1829 ret = validate_event_name(event->name);
1830 if (ret) {
1831 goto error;
1832 }
1833
1834 switch (domain->type) {
1835 case LTTNG_DOMAIN_KERNEL:
1836 {
1837 struct ltt_kernel_channel *kchan;
1838
1839 /*
1840 * If a non-default channel has been created in the
1841 * session, explicitely require that -c chan_name needs
1842 * to be provided.
1843 */
1844 if (session->kernel_session->has_non_default_channel
1845 && channel_name[0] == '\0') {
1846 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1847 goto error;
1848 }
1849
1850 kchan = trace_kernel_get_channel_by_name(channel_name,
1851 session->kernel_session);
1852 if (kchan == NULL) {
1853 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1854 LTTNG_BUFFER_GLOBAL);
1855 if (attr == NULL) {
1856 ret = LTTNG_ERR_FATAL;
1857 goto error;
1858 }
1859 if (lttng_strncpy(attr->name, channel_name,
1860 sizeof(attr->name))) {
1861 ret = LTTNG_ERR_INVALID;
1862 goto error;
1863 }
1864
1865 ret = cmd_enable_channel(session, domain, attr, wpipe);
1866 if (ret != LTTNG_OK) {
1867 goto error;
1868 }
1869 channel_created = 1;
1870 }
1871
1872 /* Get the newly created kernel channel pointer */
1873 kchan = trace_kernel_get_channel_by_name(channel_name,
1874 session->kernel_session);
1875 if (kchan == NULL) {
1876 /* This sould not happen... */
1877 ret = LTTNG_ERR_FATAL;
1878 goto error;
1879 }
1880
1881 switch (event->type) {
1882 case LTTNG_EVENT_ALL:
1883 {
1884 char *filter_expression_a = NULL;
1885 struct lttng_filter_bytecode *filter_a = NULL;
1886
1887 /*
1888 * We need to duplicate filter_expression and filter,
1889 * because ownership is passed to first enable
1890 * event.
1891 */
1892 if (filter_expression) {
1893 filter_expression_a = strdup(filter_expression);
1894 if (!filter_expression_a) {
1895 ret = LTTNG_ERR_FATAL;
1896 goto error;
1897 }
1898 }
1899 if (filter) {
1900 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1901 if (!filter_a) {
1902 free(filter_expression_a);
1903 ret = LTTNG_ERR_FATAL;
1904 goto error;
1905 }
1906 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1907 }
1908 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1909 ret = event_kernel_enable_event(kchan, event,
1910 filter_expression, filter);
1911 /* We have passed ownership */
1912 filter_expression = NULL;
1913 filter = NULL;
1914 if (ret != LTTNG_OK) {
1915 if (channel_created) {
1916 /* Let's not leak a useless channel. */
1917 kernel_destroy_channel(kchan);
1918 }
1919 free(filter_expression_a);
1920 free(filter_a);
1921 goto error;
1922 }
1923 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1924 ret = event_kernel_enable_event(kchan, event,
1925 filter_expression_a, filter_a);
1926 /* We have passed ownership */
1927 filter_expression_a = NULL;
1928 filter_a = NULL;
1929 if (ret != LTTNG_OK) {
1930 goto error;
1931 }
1932 break;
1933 }
1934 case LTTNG_EVENT_PROBE:
1935 case LTTNG_EVENT_FUNCTION:
1936 case LTTNG_EVENT_FUNCTION_ENTRY:
1937 case LTTNG_EVENT_TRACEPOINT:
1938 ret = event_kernel_enable_event(kchan, event,
1939 filter_expression, filter);
1940 /* We have passed ownership */
1941 filter_expression = NULL;
1942 filter = NULL;
1943 if (ret != LTTNG_OK) {
1944 if (channel_created) {
1945 /* Let's not leak a useless channel. */
1946 kernel_destroy_channel(kchan);
1947 }
1948 goto error;
1949 }
1950 break;
1951 case LTTNG_EVENT_SYSCALL:
1952 ret = event_kernel_enable_event(kchan, event,
1953 filter_expression, filter);
1954 /* We have passed ownership */
1955 filter_expression = NULL;
1956 filter = NULL;
1957 if (ret != LTTNG_OK) {
1958 goto error;
1959 }
1960 break;
1961 default:
1962 ret = LTTNG_ERR_UNK;
1963 goto error;
1964 }
1965
1966 kernel_wait_quiescent(kernel_tracer_fd);
1967 break;
1968 }
1969 case LTTNG_DOMAIN_UST:
1970 {
1971 struct ltt_ust_channel *uchan;
1972 struct ltt_ust_session *usess = session->ust_session;
1973
1974 assert(usess);
1975
1976 /*
1977 * If a non-default channel has been created in the
1978 * session, explicitely require that -c chan_name needs
1979 * to be provided.
1980 */
1981 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1982 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1983 goto error;
1984 }
1985
1986 /* Get channel from global UST domain */
1987 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1988 channel_name);
1989 if (uchan == NULL) {
1990 /* Create default channel */
1991 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1992 usess->buffer_type);
1993 if (attr == NULL) {
1994 ret = LTTNG_ERR_FATAL;
1995 goto error;
1996 }
1997 if (lttng_strncpy(attr->name, channel_name,
1998 sizeof(attr->name))) {
1999 ret = LTTNG_ERR_INVALID;
2000 goto error;
2001 }
2002
2003 ret = cmd_enable_channel(session, domain, attr, wpipe);
2004 if (ret != LTTNG_OK) {
2005 goto error;
2006 }
2007
2008 /* Get the newly created channel reference back */
2009 uchan = trace_ust_find_channel_by_name(
2010 usess->domain_global.channels, channel_name);
2011 assert(uchan);
2012 }
2013
2014 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2015 /*
2016 * Don't allow users to add UST events to channels which
2017 * are assigned to a userspace subdomain (JUL, Log4J,
2018 * Python, etc.).
2019 */
2020 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2021 goto error;
2022 }
2023
2024 if (!internal_event) {
2025 /*
2026 * Ensure the event name is not reserved for internal
2027 * use.
2028 */
2029 ret = validate_ust_event_name(event->name);
2030 if (ret) {
2031 WARN("Userspace event name %s failed validation.",
2032 event->name ?
2033 event->name : "NULL");
2034 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2035 goto error;
2036 }
2037 }
2038
2039 /* At this point, the session and channel exist on the tracer */
2040 ret = event_ust_enable_tracepoint(usess, uchan, event,
2041 filter_expression, filter, exclusion,
2042 internal_event);
2043 /* We have passed ownership */
2044 filter_expression = NULL;
2045 filter = NULL;
2046 exclusion = NULL;
2047 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2048 goto already_enabled;
2049 } else if (ret != LTTNG_OK) {
2050 goto error;
2051 }
2052 break;
2053 }
2054 case LTTNG_DOMAIN_LOG4J:
2055 case LTTNG_DOMAIN_JUL:
2056 case LTTNG_DOMAIN_PYTHON:
2057 {
2058 const char *default_event_name, *default_chan_name;
2059 struct agent *agt;
2060 struct lttng_event uevent;
2061 struct lttng_domain tmp_dom;
2062 struct ltt_ust_session *usess = session->ust_session;
2063
2064 assert(usess);
2065
2066 agt = trace_ust_find_agent(usess, domain->type);
2067 if (!agt) {
2068 agt = agent_create(domain->type);
2069 if (!agt) {
2070 ret = LTTNG_ERR_NOMEM;
2071 goto error;
2072 }
2073 agent_add(agt, usess->agents);
2074 }
2075
2076 /* Create the default tracepoint. */
2077 memset(&uevent, 0, sizeof(uevent));
2078 uevent.type = LTTNG_EVENT_TRACEPOINT;
2079 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2080 default_event_name = event_get_default_agent_ust_name(
2081 domain->type);
2082 if (!default_event_name) {
2083 ret = LTTNG_ERR_FATAL;
2084 goto error;
2085 }
2086 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2087 uevent.name[sizeof(uevent.name) - 1] = '\0';
2088
2089 /*
2090 * The domain type is changed because we are about to enable the
2091 * default channel and event for the JUL domain that are hardcoded.
2092 * This happens in the UST domain.
2093 */
2094 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2095 tmp_dom.type = LTTNG_DOMAIN_UST;
2096
2097 switch (domain->type) {
2098 case LTTNG_DOMAIN_LOG4J:
2099 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2100 break;
2101 case LTTNG_DOMAIN_JUL:
2102 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2103 break;
2104 case LTTNG_DOMAIN_PYTHON:
2105 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2106 break;
2107 default:
2108 /* The switch/case we are in makes this impossible */
2109 assert(0);
2110 }
2111
2112 {
2113 char *filter_expression_copy = NULL;
2114 struct lttng_filter_bytecode *filter_copy = NULL;
2115
2116 if (filter) {
2117 const size_t filter_size = sizeof(
2118 struct lttng_filter_bytecode)
2119 + filter->len;
2120
2121 filter_copy = zmalloc(filter_size);
2122 if (!filter_copy) {
2123 ret = LTTNG_ERR_NOMEM;
2124 goto error;
2125 }
2126 memcpy(filter_copy, filter, filter_size);
2127
2128 filter_expression_copy =
2129 strdup(filter_expression);
2130 if (!filter_expression) {
2131 ret = LTTNG_ERR_NOMEM;
2132 }
2133
2134 if (!filter_expression_copy || !filter_copy) {
2135 free(filter_expression_copy);
2136 free(filter_copy);
2137 goto error;
2138 }
2139 }
2140
2141 ret = cmd_enable_event_internal(session, &tmp_dom,
2142 (char *) default_chan_name,
2143 &uevent, filter_expression_copy,
2144 filter_copy, NULL, wpipe);
2145 }
2146
2147 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2148 goto already_enabled;
2149 } else if (ret != LTTNG_OK) {
2150 goto error;
2151 }
2152
2153 /* The wild card * means that everything should be enabled. */
2154 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2155 ret = event_agent_enable_all(usess, agt, event, filter,
2156 filter_expression);
2157 } else {
2158 ret = event_agent_enable(usess, agt, event, filter,
2159 filter_expression);
2160 }
2161 filter = NULL;
2162 filter_expression = NULL;
2163 if (ret != LTTNG_OK) {
2164 goto error;
2165 }
2166
2167 break;
2168 }
2169 default:
2170 ret = LTTNG_ERR_UND;
2171 goto error;
2172 }
2173
2174 ret = LTTNG_OK;
2175
2176 already_enabled:
2177 error:
2178 free(filter_expression);
2179 free(filter);
2180 free(exclusion);
2181 free(attr);
2182 rcu_read_unlock();
2183 return ret;
2184 }
2185
2186 /*
2187 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2188 * We own filter, exclusion, and filter_expression.
2189 */
2190 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
2191 char *channel_name, struct lttng_event *event,
2192 char *filter_expression,
2193 struct lttng_filter_bytecode *filter,
2194 struct lttng_event_exclusion *exclusion,
2195 int wpipe)
2196 {
2197 return _cmd_enable_event(session, domain, channel_name, event,
2198 filter_expression, filter, exclusion, wpipe, false);
2199 }
2200
2201 /*
2202 * Enable an event which is internal to LTTng. An internal should
2203 * never be made visible to clients and are immune to checks such as
2204 * reserved names.
2205 */
2206 static int cmd_enable_event_internal(struct ltt_session *session,
2207 struct lttng_domain *domain,
2208 char *channel_name, struct lttng_event *event,
2209 char *filter_expression,
2210 struct lttng_filter_bytecode *filter,
2211 struct lttng_event_exclusion *exclusion,
2212 int wpipe)
2213 {
2214 return _cmd_enable_event(session, domain, channel_name, event,
2215 filter_expression, filter, exclusion, wpipe, true);
2216 }
2217
2218 /*
2219 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2220 */
2221 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2222 struct lttng_event **events)
2223 {
2224 int ret;
2225 ssize_t nb_events = 0;
2226
2227 switch (domain) {
2228 case LTTNG_DOMAIN_KERNEL:
2229 nb_events = kernel_list_events(kernel_tracer_fd, events);
2230 if (nb_events < 0) {
2231 ret = LTTNG_ERR_KERN_LIST_FAIL;
2232 goto error;
2233 }
2234 break;
2235 case LTTNG_DOMAIN_UST:
2236 nb_events = ust_app_list_events(events);
2237 if (nb_events < 0) {
2238 ret = LTTNG_ERR_UST_LIST_FAIL;
2239 goto error;
2240 }
2241 break;
2242 case LTTNG_DOMAIN_LOG4J:
2243 case LTTNG_DOMAIN_JUL:
2244 case LTTNG_DOMAIN_PYTHON:
2245 nb_events = agent_list_events(events, domain);
2246 if (nb_events < 0) {
2247 ret = LTTNG_ERR_UST_LIST_FAIL;
2248 goto error;
2249 }
2250 break;
2251 default:
2252 ret = LTTNG_ERR_UND;
2253 goto error;
2254 }
2255
2256 return nb_events;
2257
2258 error:
2259 /* Return negative value to differentiate return code */
2260 return -ret;
2261 }
2262
2263 /*
2264 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2265 */
2266 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2267 struct lttng_event_field **fields)
2268 {
2269 int ret;
2270 ssize_t nb_fields = 0;
2271
2272 switch (domain) {
2273 case LTTNG_DOMAIN_UST:
2274 nb_fields = ust_app_list_event_fields(fields);
2275 if (nb_fields < 0) {
2276 ret = LTTNG_ERR_UST_LIST_FAIL;
2277 goto error;
2278 }
2279 break;
2280 case LTTNG_DOMAIN_KERNEL:
2281 default: /* fall-through */
2282 ret = LTTNG_ERR_UND;
2283 goto error;
2284 }
2285
2286 return nb_fields;
2287
2288 error:
2289 /* Return negative value to differentiate return code */
2290 return -ret;
2291 }
2292
2293 ssize_t cmd_list_syscalls(struct lttng_event **events)
2294 {
2295 return syscall_table_list(events);
2296 }
2297
2298 /*
2299 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2300 *
2301 * Called with session lock held.
2302 */
2303 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2304 enum lttng_domain_type domain, int32_t **pids)
2305 {
2306 int ret;
2307 ssize_t nr_pids = 0;
2308
2309 switch (domain) {
2310 case LTTNG_DOMAIN_KERNEL:
2311 {
2312 struct ltt_kernel_session *ksess;
2313
2314 ksess = session->kernel_session;
2315 nr_pids = kernel_list_tracker_pids(ksess, pids);
2316 if (nr_pids < 0) {
2317 ret = LTTNG_ERR_KERN_LIST_FAIL;
2318 goto error;
2319 }
2320 break;
2321 }
2322 case LTTNG_DOMAIN_UST:
2323 {
2324 struct ltt_ust_session *usess;
2325
2326 usess = session->ust_session;
2327 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2328 if (nr_pids < 0) {
2329 ret = LTTNG_ERR_UST_LIST_FAIL;
2330 goto error;
2331 }
2332 break;
2333 }
2334 case LTTNG_DOMAIN_LOG4J:
2335 case LTTNG_DOMAIN_JUL:
2336 case LTTNG_DOMAIN_PYTHON:
2337 default:
2338 ret = LTTNG_ERR_UND;
2339 goto error;
2340 }
2341
2342 return nr_pids;
2343
2344 error:
2345 /* Return negative value to differentiate return code */
2346 return -ret;
2347 }
2348
2349 /*
2350 * Command LTTNG_START_TRACE processed by the client thread.
2351 *
2352 * Called with session mutex held.
2353 */
2354 int cmd_start_trace(struct ltt_session *session)
2355 {
2356 int ret;
2357 unsigned long nb_chan = 0;
2358 struct ltt_kernel_session *ksession;
2359 struct ltt_ust_session *usess;
2360
2361 assert(session);
2362
2363 /* Ease our life a bit ;) */
2364 ksession = session->kernel_session;
2365 usess = session->ust_session;
2366
2367 /* Is the session already started? */
2368 if (session->active) {
2369 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2370 goto error;
2371 }
2372
2373 /*
2374 * Starting a session without channel is useless since after that it's not
2375 * possible to enable channel thus inform the client.
2376 */
2377 if (usess && usess->domain_global.channels) {
2378 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2379 }
2380 if (ksession) {
2381 nb_chan += ksession->channel_count;
2382 }
2383 if (!nb_chan) {
2384 ret = LTTNG_ERR_NO_CHANNEL;
2385 goto error;
2386 }
2387
2388 /* Kernel tracing */
2389 if (ksession != NULL) {
2390 ret = start_kernel_session(ksession, kernel_tracer_fd);
2391 if (ret != LTTNG_OK) {
2392 goto error;
2393 }
2394 }
2395
2396 /* Flag session that trace should start automatically */
2397 if (usess) {
2398 /*
2399 * Even though the start trace might fail, flag this session active so
2400 * other application coming in are started by default.
2401 */
2402 usess->active = 1;
2403
2404 ret = ust_app_start_trace_all(usess);
2405 if (ret < 0) {
2406 ret = LTTNG_ERR_UST_START_FAIL;
2407 goto error;
2408 }
2409 }
2410
2411 /* Flag this after a successful start. */
2412 session->has_been_started = 1;
2413 session->active = 1;
2414
2415 ret = LTTNG_OK;
2416
2417 error:
2418 return ret;
2419 }
2420
2421 /*
2422 * Command LTTNG_STOP_TRACE processed by the client thread.
2423 */
2424 int cmd_stop_trace(struct ltt_session *session)
2425 {
2426 int ret;
2427 struct ltt_kernel_channel *kchan;
2428 struct ltt_kernel_session *ksession;
2429 struct ltt_ust_session *usess;
2430
2431 assert(session);
2432
2433 /* Short cut */
2434 ksession = session->kernel_session;
2435 usess = session->ust_session;
2436
2437 /* Session is not active. Skip everythong and inform the client. */
2438 if (!session->active) {
2439 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2440 goto error;
2441 }
2442
2443 /* Kernel tracer */
2444 if (ksession && ksession->active) {
2445 DBG("Stop kernel tracing");
2446
2447 /* Flush metadata if exist */
2448 if (ksession->metadata_stream_fd >= 0) {
2449 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2450 if (ret < 0) {
2451 ERR("Kernel metadata flush failed");
2452 }
2453 }
2454
2455 /* Flush all buffers before stopping */
2456 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2457 ret = kernel_flush_buffer(kchan);
2458 if (ret < 0) {
2459 ERR("Kernel flush buffer error");
2460 }
2461 }
2462
2463 ret = kernel_stop_session(ksession);
2464 if (ret < 0) {
2465 ret = LTTNG_ERR_KERN_STOP_FAIL;
2466 goto error;
2467 }
2468
2469 kernel_wait_quiescent(kernel_tracer_fd);
2470
2471 ksession->active = 0;
2472 }
2473
2474 if (usess && usess->active) {
2475 /*
2476 * Even though the stop trace might fail, flag this session inactive so
2477 * other application coming in are not started by default.
2478 */
2479 usess->active = 0;
2480
2481 ret = ust_app_stop_trace_all(usess);
2482 if (ret < 0) {
2483 ret = LTTNG_ERR_UST_STOP_FAIL;
2484 goto error;
2485 }
2486 }
2487
2488 /* Flag inactive after a successful stop. */
2489 session->active = 0;
2490 ret = LTTNG_OK;
2491
2492 error:
2493 return ret;
2494 }
2495
2496 /*
2497 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2498 */
2499 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2500 struct lttng_uri *uris)
2501 {
2502 int ret, i;
2503 struct ltt_kernel_session *ksess = session->kernel_session;
2504 struct ltt_ust_session *usess = session->ust_session;
2505
2506 assert(session);
2507 assert(uris);
2508 assert(nb_uri > 0);
2509
2510 /* Can't set consumer URI if the session is active. */
2511 if (session->active) {
2512 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2513 goto error;
2514 }
2515
2516 /* Set the "global" consumer URIs */
2517 for (i = 0; i < nb_uri; i++) {
2518 ret = add_uri_to_consumer(session->consumer,
2519 &uris[i], 0, session->name);
2520 if (ret != LTTNG_OK) {
2521 goto error;
2522 }
2523 }
2524
2525 /* Set UST session URIs */
2526 if (session->ust_session) {
2527 for (i = 0; i < nb_uri; i++) {
2528 ret = add_uri_to_consumer(
2529 session->ust_session->consumer,
2530 &uris[i], LTTNG_DOMAIN_UST,
2531 session->name);
2532 if (ret != LTTNG_OK) {
2533 goto error;
2534 }
2535 }
2536 }
2537
2538 /* Set kernel session URIs */
2539 if (session->kernel_session) {
2540 for (i = 0; i < nb_uri; i++) {
2541 ret = add_uri_to_consumer(
2542 session->kernel_session->consumer,
2543 &uris[i], LTTNG_DOMAIN_KERNEL,
2544 session->name);
2545 if (ret != LTTNG_OK) {
2546 goto error;
2547 }
2548 }
2549 }
2550
2551 /*
2552 * Make sure to set the session in output mode after we set URI since a
2553 * session can be created without URL (thus flagged in no output mode).
2554 */
2555 session->output_traces = 1;
2556 if (ksess) {
2557 ksess->output_traces = 1;
2558 }
2559
2560 if (usess) {
2561 usess->output_traces = 1;
2562 }
2563
2564 /* All good! */
2565 ret = LTTNG_OK;
2566
2567 error:
2568 return ret;
2569 }
2570
2571 /*
2572 * Command LTTNG_CREATE_SESSION processed by the client thread.
2573 */
2574 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2575 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2576 {
2577 int ret;
2578 struct ltt_session *session;
2579
2580 assert(name);
2581 assert(creds);
2582
2583 /*
2584 * Verify if the session already exist
2585 *
2586 * XXX: There is no need for the session lock list here since the caller
2587 * (process_client_msg) is holding it. We might want to change that so a
2588 * single command does not lock the entire session list.
2589 */
2590 session = session_find_by_name(name);
2591 if (session != NULL) {
2592 ret = LTTNG_ERR_EXIST_SESS;
2593 goto find_error;
2594 }
2595
2596 /* Create tracing session in the registry */
2597 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2598 LTTNG_SOCK_GET_GID_CRED(creds));
2599 if (ret != LTTNG_OK) {
2600 goto session_error;
2601 }
2602
2603 /*
2604 * Get the newly created session pointer back
2605 *
2606 * XXX: There is no need for the session lock list here since the caller
2607 * (process_client_msg) is holding it. We might want to change that so a
2608 * single command does not lock the entire session list.
2609 */
2610 session = session_find_by_name(name);
2611 assert(session);
2612
2613 session->live_timer = live_timer;
2614 /* Create default consumer output for the session not yet created. */
2615 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2616 if (session->consumer == NULL) {
2617 ret = LTTNG_ERR_FATAL;
2618 goto consumer_error;
2619 }
2620
2621 if (uris) {
2622 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2623 if (ret != LTTNG_OK) {
2624 goto consumer_error;
2625 }
2626 session->output_traces = 1;
2627 } else {
2628 session->output_traces = 0;
2629 DBG2("Session %s created with no output", session->name);
2630 }
2631
2632 session->consumer->enabled = 1;
2633
2634 return LTTNG_OK;
2635
2636 consumer_error:
2637 session_destroy(session);
2638 session_error:
2639 find_error:
2640 return ret;
2641 }
2642
2643 /*
2644 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2645 */
2646 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2647 size_t nb_uri, lttng_sock_cred *creds)
2648 {
2649 int ret;
2650 struct ltt_session *session;
2651 struct snapshot_output *new_output = NULL;
2652
2653 assert(name);
2654 assert(creds);
2655
2656 /*
2657 * Create session in no output mode with URIs set to NULL. The uris we've
2658 * received are for a default snapshot output if one.
2659 */
2660 ret = cmd_create_session_uri(name, NULL, 0, creds, 0);
2661 if (ret != LTTNG_OK) {
2662 goto error;
2663 }
2664
2665 /* Get the newly created session pointer back. This should NEVER fail. */
2666 session = session_find_by_name(name);
2667 assert(session);
2668
2669 /* Flag session for snapshot mode. */
2670 session->snapshot_mode = 1;
2671
2672 /* Skip snapshot output creation if no URI is given. */
2673 if (nb_uri == 0) {
2674 goto end;
2675 }
2676
2677 new_output = snapshot_output_alloc();
2678 if (!new_output) {
2679 ret = LTTNG_ERR_NOMEM;
2680 goto error_snapshot_alloc;
2681 }
2682
2683 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2684 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2685 if (ret < 0) {
2686 if (ret == -ENOMEM) {
2687 ret = LTTNG_ERR_NOMEM;
2688 } else {
2689 ret = LTTNG_ERR_INVALID;
2690 }
2691 goto error_snapshot;
2692 }
2693
2694 rcu_read_lock();
2695 snapshot_add_output(&session->snapshot, new_output);
2696 rcu_read_unlock();
2697
2698 end:
2699 return LTTNG_OK;
2700
2701 error_snapshot:
2702 snapshot_output_destroy(new_output);
2703 error_snapshot_alloc:
2704 session_destroy(session);
2705 error:
2706 return ret;
2707 }
2708
2709 /*
2710 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2711 *
2712 * Called with session lock held.
2713 */
2714 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2715 {
2716 int ret;
2717 struct ltt_ust_session *usess;
2718 struct ltt_kernel_session *ksess;
2719
2720 /* Safety net */
2721 assert(session);
2722
2723 usess = session->ust_session;
2724 ksess = session->kernel_session;
2725
2726 /* Clean kernel session teardown */
2727 kernel_destroy_session(ksess);
2728
2729 /* UST session teardown */
2730 if (usess) {
2731 /* Close any relayd session */
2732 consumer_output_send_destroy_relayd(usess->consumer);
2733
2734 /* Destroy every UST application related to this session. */
2735 ret = ust_app_destroy_trace_all(usess);
2736 if (ret) {
2737 ERR("Error in ust_app_destroy_trace_all");
2738 }
2739
2740 /* Clean up the rest. */
2741 trace_ust_destroy_session(usess);
2742 }
2743
2744 /*
2745 * Must notify the kernel thread here to update it's poll set in order to
2746 * remove the channel(s)' fd just destroyed.
2747 */
2748 ret = notify_thread_pipe(wpipe);
2749 if (ret < 0) {
2750 PERROR("write kernel poll pipe");
2751 }
2752
2753 ret = session_destroy(session);
2754
2755 return ret;
2756 }
2757
2758 /*
2759 * Command LTTNG_CALIBRATE processed by the client thread.
2760 */
2761 int cmd_calibrate(enum lttng_domain_type domain,
2762 struct lttng_calibrate *calibrate)
2763 {
2764 int ret;
2765
2766 switch (domain) {
2767 case LTTNG_DOMAIN_KERNEL:
2768 {
2769 struct lttng_kernel_calibrate kcalibrate;
2770
2771 switch (calibrate->type) {
2772 case LTTNG_CALIBRATE_FUNCTION:
2773 default:
2774 /* Default and only possible calibrate option. */
2775 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2776 break;
2777 }
2778
2779 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2780 if (ret < 0) {
2781 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2782 goto error;
2783 }
2784 break;
2785 }
2786 case LTTNG_DOMAIN_UST:
2787 {
2788 struct lttng_ust_calibrate ucalibrate;
2789
2790 switch (calibrate->type) {
2791 case LTTNG_CALIBRATE_FUNCTION:
2792 default:
2793 /* Default and only possible calibrate option. */
2794 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2795 break;
2796 }
2797
2798 ret = ust_app_calibrate_glb(&ucalibrate);
2799 if (ret < 0) {
2800 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2801 goto error;
2802 }
2803 break;
2804 }
2805 default:
2806 ret = LTTNG_ERR_UND;
2807 goto error;
2808 }
2809
2810 ret = LTTNG_OK;
2811
2812 error:
2813 return ret;
2814 }
2815
2816 /*
2817 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2818 */
2819 int cmd_register_consumer(struct ltt_session *session,
2820 enum lttng_domain_type domain, const char *sock_path,
2821 struct consumer_data *cdata)
2822 {
2823 int ret, sock;
2824 struct consumer_socket *socket = NULL;
2825
2826 assert(session);
2827 assert(cdata);
2828 assert(sock_path);
2829
2830 switch (domain) {
2831 case LTTNG_DOMAIN_KERNEL:
2832 {
2833 struct ltt_kernel_session *ksess = session->kernel_session;
2834
2835 assert(ksess);
2836
2837 /* Can't register a consumer if there is already one */
2838 if (ksess->consumer_fds_sent != 0) {
2839 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2840 goto error;
2841 }
2842
2843 sock = lttcomm_connect_unix_sock(sock_path);
2844 if (sock < 0) {
2845 ret = LTTNG_ERR_CONNECT_FAIL;
2846 goto error;
2847 }
2848 cdata->cmd_sock = sock;
2849
2850 socket = consumer_allocate_socket(&cdata->cmd_sock);
2851 if (socket == NULL) {
2852 ret = close(sock);
2853 if (ret < 0) {
2854 PERROR("close register consumer");
2855 }
2856 cdata->cmd_sock = -1;
2857 ret = LTTNG_ERR_FATAL;
2858 goto error;
2859 }
2860
2861 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2862 if (socket->lock == NULL) {
2863 PERROR("zmalloc pthread mutex");
2864 ret = LTTNG_ERR_FATAL;
2865 goto error;
2866 }
2867 pthread_mutex_init(socket->lock, NULL);
2868 socket->registered = 1;
2869
2870 rcu_read_lock();
2871 consumer_add_socket(socket, ksess->consumer);
2872 rcu_read_unlock();
2873
2874 pthread_mutex_lock(&cdata->pid_mutex);
2875 cdata->pid = -1;
2876 pthread_mutex_unlock(&cdata->pid_mutex);
2877
2878 break;
2879 }
2880 default:
2881 /* TODO: Userspace tracing */
2882 ret = LTTNG_ERR_UND;
2883 goto error;
2884 }
2885
2886 return LTTNG_OK;
2887
2888 error:
2889 if (socket) {
2890 consumer_destroy_socket(socket);
2891 }
2892 return ret;
2893 }
2894
2895 /*
2896 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2897 */
2898 ssize_t cmd_list_domains(struct ltt_session *session,
2899 struct lttng_domain **domains)
2900 {
2901 int ret, index = 0;
2902 ssize_t nb_dom = 0;
2903 struct agent *agt;
2904 struct lttng_ht_iter iter;
2905
2906 if (session->kernel_session != NULL) {
2907 DBG3("Listing domains found kernel domain");
2908 nb_dom++;
2909 }
2910
2911 if (session->ust_session != NULL) {
2912 DBG3("Listing domains found UST global domain");
2913 nb_dom++;
2914
2915 rcu_read_lock();
2916 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2917 agt, node.node) {
2918 if (agt->being_used) {
2919 nb_dom++;
2920 }
2921 }
2922 rcu_read_unlock();
2923 }
2924
2925 if (!nb_dom) {
2926 goto end;
2927 }
2928
2929 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2930 if (*domains == NULL) {
2931 ret = LTTNG_ERR_FATAL;
2932 goto error;
2933 }
2934
2935 if (session->kernel_session != NULL) {
2936 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2937
2938 /* Kernel session buffer type is always GLOBAL */
2939 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2940
2941 index++;
2942 }
2943
2944 if (session->ust_session != NULL) {
2945 (*domains)[index].type = LTTNG_DOMAIN_UST;
2946 (*domains)[index].buf_type = session->ust_session->buffer_type;
2947 index++;
2948
2949 rcu_read_lock();
2950 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2951 agt, node.node) {
2952 if (agt->being_used) {
2953 (*domains)[index].type = agt->domain;
2954 (*domains)[index].buf_type = session->ust_session->buffer_type;
2955 index++;
2956 }
2957 }
2958 rcu_read_unlock();
2959 }
2960 end:
2961 return nb_dom;
2962
2963 error:
2964 /* Return negative value to differentiate return code */
2965 return -ret;
2966 }
2967
2968
2969 /*
2970 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2971 */
2972 ssize_t cmd_list_channels(enum lttng_domain_type domain,
2973 struct ltt_session *session, struct lttng_channel **channels)
2974 {
2975 ssize_t nb_chan = 0, payload_size = 0, ret;
2976
2977 switch (domain) {
2978 case LTTNG_DOMAIN_KERNEL:
2979 if (session->kernel_session != NULL) {
2980 nb_chan = session->kernel_session->channel_count;
2981 }
2982 DBG3("Number of kernel channels %zd", nb_chan);
2983 if (nb_chan <= 0) {
2984 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2985 goto end;
2986 }
2987 break;
2988 case LTTNG_DOMAIN_UST:
2989 if (session->ust_session != NULL) {
2990 rcu_read_lock();
2991 nb_chan = lttng_ht_get_count(
2992 session->ust_session->domain_global.channels);
2993 rcu_read_unlock();
2994 }
2995 DBG3("Number of UST global channels %zd", nb_chan);
2996 if (nb_chan < 0) {
2997 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
2998 goto end;
2999 }
3000 break;
3001 default:
3002 ret = -LTTNG_ERR_UND;
3003 goto end;
3004 }
3005
3006 if (nb_chan > 0) {
3007 const size_t channel_size = sizeof(struct lttng_channel) +
3008 sizeof(struct lttcomm_channel_extended);
3009 struct lttcomm_channel_extended *channel_exts;
3010
3011 payload_size = nb_chan * channel_size;
3012 *channels = zmalloc(payload_size);
3013 if (*channels == NULL) {
3014 ret = -LTTNG_ERR_FATAL;
3015 goto end;
3016 }
3017
3018 channel_exts = ((void *) *channels) +
3019 (nb_chan * sizeof(struct lttng_channel));
3020 list_lttng_channels(domain, session, *channels, channel_exts);
3021 } else {
3022 *channels = NULL;
3023 }
3024
3025 ret = payload_size;
3026 end:
3027 return ret;
3028 }
3029
3030 /*
3031 * Command LTTNG_LIST_EVENTS processed by the client thread.
3032 */
3033 ssize_t cmd_list_events(enum lttng_domain_type domain,
3034 struct ltt_session *session, char *channel_name,
3035 struct lttng_event **events, size_t *total_size)
3036 {
3037 int ret = 0;
3038 ssize_t nb_event = 0;
3039
3040 switch (domain) {
3041 case LTTNG_DOMAIN_KERNEL:
3042 if (session->kernel_session != NULL) {
3043 nb_event = list_lttng_kernel_events(channel_name,
3044 session->kernel_session, events,
3045 total_size);
3046 }
3047 break;
3048 case LTTNG_DOMAIN_UST:
3049 {
3050 if (session->ust_session != NULL) {
3051 nb_event = list_lttng_ust_global_events(channel_name,
3052 &session->ust_session->domain_global, events,
3053 total_size);
3054 }
3055 break;
3056 }
3057 case LTTNG_DOMAIN_LOG4J:
3058 case LTTNG_DOMAIN_JUL:
3059 case LTTNG_DOMAIN_PYTHON:
3060 if (session->ust_session) {
3061 struct lttng_ht_iter iter;
3062 struct agent *agt;
3063
3064 rcu_read_lock();
3065 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3066 &iter.iter, agt, node.node) {
3067 if (agt->domain == domain) {
3068 nb_event = list_lttng_agent_events(
3069 agt, events,
3070 total_size);
3071 break;
3072 }
3073 }
3074 rcu_read_unlock();
3075 }
3076 break;
3077 default:
3078 ret = LTTNG_ERR_UND;
3079 goto error;
3080 }
3081
3082 return nb_event;
3083
3084 error:
3085 /* Return negative value to differentiate return code */
3086 return -ret;
3087 }
3088
3089 /*
3090 * Using the session list, filled a lttng_session array to send back to the
3091 * client for session listing.
3092 *
3093 * The session list lock MUST be acquired before calling this function. Use
3094 * session_lock_list() and session_unlock_list().
3095 */
3096 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
3097 gid_t gid)
3098 {
3099 int ret;
3100 unsigned int i = 0;
3101 struct ltt_session *session;
3102 struct ltt_session_list *list = session_get_list();
3103
3104 DBG("Getting all available session for UID %d GID %d",
3105 uid, gid);
3106 /*
3107 * Iterate over session list and append data after the control struct in
3108 * the buffer.
3109 */
3110 cds_list_for_each_entry(session, &list->head, list) {
3111 /*
3112 * Only list the sessions the user can control.
3113 */
3114 if (!session_access_ok(session, uid, gid)) {
3115 continue;
3116 }
3117
3118 struct ltt_kernel_session *ksess = session->kernel_session;
3119 struct ltt_ust_session *usess = session->ust_session;
3120
3121 if (session->consumer->type == CONSUMER_DST_NET ||
3122 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3123 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3124 ret = build_network_session_path(sessions[i].path,
3125 sizeof(sessions[i].path), session);
3126 } else {
3127 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3128 session->consumer->dst.trace_path);
3129 }
3130 if (ret < 0) {
3131 PERROR("snprintf session path");
3132 continue;
3133 }
3134
3135 strncpy(sessions[i].name, session->name, NAME_MAX);
3136 sessions[i].name[NAME_MAX - 1] = '\0';
3137 sessions[i].enabled = session->active;
3138 sessions[i].snapshot_mode = session->snapshot_mode;
3139 sessions[i].live_timer_interval = session->live_timer;
3140 i++;
3141 }
3142 }
3143
3144 /*
3145 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3146 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3147 */
3148 int cmd_data_pending(struct ltt_session *session)
3149 {
3150 int ret;
3151 struct ltt_kernel_session *ksess = session->kernel_session;
3152 struct ltt_ust_session *usess = session->ust_session;
3153
3154 assert(session);
3155
3156 /* Session MUST be stopped to ask for data availability. */
3157 if (session->active) {
3158 ret = LTTNG_ERR_SESSION_STARTED;
3159 goto error;
3160 } else {
3161 /*
3162 * If stopped, just make sure we've started before else the above call
3163 * will always send that there is data pending.
3164 *
3165 * The consumer assumes that when the data pending command is received,
3166 * the trace has been started before or else no output data is written
3167 * by the streams which is a condition for data pending. So, this is
3168 * *VERY* important that we don't ask the consumer before a start
3169 * trace.
3170 */
3171 if (!session->has_been_started) {
3172 ret = 0;
3173 goto error;
3174 }
3175 }
3176
3177 if (ksess && ksess->consumer) {
3178 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3179 if (ret == 1) {
3180 /* Data is still being extracted for the kernel. */
3181 goto error;
3182 }
3183 }
3184
3185 if (usess && usess->consumer) {
3186 ret = consumer_is_data_pending(usess->id, usess->consumer);
3187 if (ret == 1) {
3188 /* Data is still being extracted for the kernel. */
3189 goto error;
3190 }
3191 }
3192
3193 /* Data is ready to be read by a viewer */
3194 ret = 0;
3195
3196 error:
3197 return ret;
3198 }
3199
3200 /*
3201 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3202 *
3203 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3204 */
3205 int cmd_snapshot_add_output(struct ltt_session *session,
3206 struct lttng_snapshot_output *output, uint32_t *id)
3207 {
3208 int ret;
3209 struct snapshot_output *new_output;
3210
3211 assert(session);
3212 assert(output);
3213
3214 DBG("Cmd snapshot add output for session %s", session->name);
3215
3216 /*
3217 * Permission denied to create an output if the session is not
3218 * set in no output mode.
3219 */
3220 if (session->output_traces) {
3221 ret = LTTNG_ERR_EPERM;
3222 goto error;
3223 }
3224
3225 /* Only one output is allowed until we have the "tee" feature. */
3226 if (session->snapshot.nb_output == 1) {
3227 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3228 goto error;
3229 }
3230
3231 new_output = snapshot_output_alloc();
3232 if (!new_output) {
3233 ret = LTTNG_ERR_NOMEM;
3234 goto error;
3235 }
3236
3237 ret = snapshot_output_init(output->max_size, output->name,
3238 output->ctrl_url, output->data_url, session->consumer, new_output,
3239 &session->snapshot);
3240 if (ret < 0) {
3241 if (ret == -ENOMEM) {
3242 ret = LTTNG_ERR_NOMEM;
3243 } else {
3244 ret = LTTNG_ERR_INVALID;
3245 }
3246 goto free_error;
3247 }
3248
3249 rcu_read_lock();
3250 snapshot_add_output(&session->snapshot, new_output);
3251 if (id) {
3252 *id = new_output->id;
3253 }
3254 rcu_read_unlock();
3255
3256 return LTTNG_OK;
3257
3258 free_error:
3259 snapshot_output_destroy(new_output);
3260 error:
3261 return ret;
3262 }
3263
3264 /*
3265 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3266 *
3267 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3268 */
3269 int cmd_snapshot_del_output(struct ltt_session *session,
3270 struct lttng_snapshot_output *output)
3271 {
3272 int ret;
3273 struct snapshot_output *sout = NULL;
3274
3275 assert(session);
3276 assert(output);
3277