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Fix: sessiond: leak of trace chunk on destruction error
[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 #include <sys/stat.h>
25 #include <stdio.h>
26
27 #include <common/defaults.h>
28 #include <common/common.h>
29 #include <common/sessiond-comm/sessiond-comm.h>
30 #include <common/relayd/relayd.h>
31 #include <common/utils.h>
32 #include <common/compat/string.h>
33 #include <common/kernel-ctl/kernel-ctl.h>
34 #include <common/dynamic-buffer.h>
35 #include <common/buffer-view.h>
36 #include <common/trace-chunk.h>
37 #include <lttng/location-internal.h>
38 #include <lttng/trigger/trigger-internal.h>
39 #include <lttng/condition/condition.h>
40 #include <lttng/action/action.h>
41 #include <lttng/channel.h>
42 #include <lttng/channel-internal.h>
43 #include <lttng/rotate-internal.h>
44 #include <lttng/location-internal.h>
45 #include <lttng/session-internal.h>
46 #include <lttng/userspace-probe-internal.h>
47 #include <lttng/session-descriptor-internal.h>
48 #include <common/string-utils/string-utils.h>
49
50 #include "channel.h"
51 #include "consumer.h"
52 #include "event.h"
53 #include "health-sessiond.h"
54 #include "kernel.h"
55 #include "kernel-consumer.h"
56 #include "lttng-sessiond.h"
57 #include "utils.h"
58 #include "lttng-syscall.h"
59 #include "agent.h"
60 #include "buffer-registry.h"
61 #include "notification-thread.h"
62 #include "notification-thread-commands.h"
63 #include "rotate.h"
64 #include "rotation-thread.h"
65 #include "timer.h"
66 #include "agent-thread.h"
67
68 #include "cmd.h"
69
70 /* Sleep for 100ms between each check for the shm path's deletion. */
71 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
72
73 struct cmd_destroy_session_reply_context {
74 int reply_sock_fd;
75 bool implicit_rotation_on_destroy;
76 /*
77 * Indicates whether or not an error occurred while launching the
78 * destruction of a session.
79 */
80 enum lttng_error_code destruction_status;
81 };
82
83 static enum lttng_error_code wait_on_path(void *path);
84
85 /*
86 * Command completion handler that is used by the destroy command
87 * when a session that has a non-default shm_path is being destroyed.
88 *
89 * See comment in cmd_destroy_session() for the rationale.
90 */
91 static struct destroy_completion_handler {
92 struct cmd_completion_handler handler;
93 char shm_path[member_sizeof(struct ltt_session, shm_path)];
94 } destroy_completion_handler = {
95 .handler = {
96 .run = wait_on_path,
97 .data = destroy_completion_handler.shm_path
98 },
99 .shm_path = { 0 },
100 };
101
102 static struct cmd_completion_handler *current_completion_handler;
103
104 /*
105 * Used to keep a unique index for each relayd socket created where this value
106 * is associated with streams on the consumer so it can match the right relayd
107 * to send to. It must be accessed with the relayd_net_seq_idx_lock
108 * held.
109 */
110 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
111 static uint64_t relayd_net_seq_idx;
112
113 static int validate_ust_event_name(const char *);
114 static int cmd_enable_event_internal(struct ltt_session *session,
115 const struct lttng_domain *domain,
116 char *channel_name, struct lttng_event *event,
117 char *filter_expression,
118 struct lttng_filter_bytecode *filter,
119 struct lttng_event_exclusion *exclusion,
120 int wpipe);
121
122 /*
123 * Create a session path used by list_lttng_sessions for the case that the
124 * session consumer is on the network.
125 */
126 static int build_network_session_path(char *dst, size_t size,
127 struct ltt_session *session)
128 {
129 int ret, kdata_port, udata_port;
130 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
131 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
132
133 assert(session);
134 assert(dst);
135
136 memset(tmp_urls, 0, sizeof(tmp_urls));
137 memset(tmp_uurl, 0, sizeof(tmp_uurl));
138
139 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
140
141 if (session->kernel_session && session->kernel_session->consumer) {
142 kuri = &session->kernel_session->consumer->dst.net.control;
143 kdata_port = session->kernel_session->consumer->dst.net.data.port;
144 }
145
146 if (session->ust_session && session->ust_session->consumer) {
147 uuri = &session->ust_session->consumer->dst.net.control;
148 udata_port = session->ust_session->consumer->dst.net.data.port;
149 }
150
151 if (uuri == NULL && kuri == NULL) {
152 uri = &session->consumer->dst.net.control;
153 kdata_port = session->consumer->dst.net.data.port;
154 } else if (kuri && uuri) {
155 ret = uri_compare(kuri, uuri);
156 if (ret) {
157 /* Not Equal */
158 uri = kuri;
159 /* Build uuri URL string */
160 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
161 if (ret < 0) {
162 goto error;
163 }
164 } else {
165 uri = kuri;
166 }
167 } else if (kuri && uuri == NULL) {
168 uri = kuri;
169 } else if (uuri && kuri == NULL) {
170 uri = uuri;
171 }
172
173 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
174 if (ret < 0) {
175 goto error;
176 }
177
178 /*
179 * Do we have a UST url set. If yes, this means we have both kernel and UST
180 * to print.
181 */
182 if (*tmp_uurl != '\0') {
183 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
184 tmp_urls, kdata_port, tmp_uurl, udata_port);
185 } else {
186 int dport;
187 if (kuri || (!kuri && !uuri)) {
188 dport = kdata_port;
189 } else {
190 /* No kernel URI, use the UST port. */
191 dport = udata_port;
192 }
193 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
194 }
195
196 error:
197 return ret;
198 }
199
200 /*
201 * Get run-time attributes if the session has been started (discarded events,
202 * lost packets).
203 */
204 static int get_kernel_runtime_stats(struct ltt_session *session,
205 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
206 uint64_t *lost_packets)
207 {
208 int ret;
209
210 if (!session->has_been_started) {
211 ret = 0;
212 *discarded_events = 0;
213 *lost_packets = 0;
214 goto end;
215 }
216
217 ret = consumer_get_discarded_events(session->id, kchan->key,
218 session->kernel_session->consumer,
219 discarded_events);
220 if (ret < 0) {
221 goto end;
222 }
223
224 ret = consumer_get_lost_packets(session->id, kchan->key,
225 session->kernel_session->consumer,
226 lost_packets);
227 if (ret < 0) {
228 goto end;
229 }
230
231 end:
232 return ret;
233 }
234
235 /*
236 * Get run-time attributes if the session has been started (discarded events,
237 * lost packets).
238 */
239 static int get_ust_runtime_stats(struct ltt_session *session,
240 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
241 uint64_t *lost_packets)
242 {
243 int ret;
244 struct ltt_ust_session *usess;
245
246 if (!discarded_events || !lost_packets) {
247 ret = -1;
248 goto end;
249 }
250
251 usess = session->ust_session;
252 assert(discarded_events);
253 assert(lost_packets);
254
255 if (!usess || !session->has_been_started) {
256 *discarded_events = 0;
257 *lost_packets = 0;
258 ret = 0;
259 goto end;
260 }
261
262 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
263 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
264 &usess->buffer_reg_uid_list,
265 usess->consumer, uchan->id,
266 uchan->attr.overwrite,
267 discarded_events,
268 lost_packets);
269 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
270 ret = ust_app_pid_get_channel_runtime_stats(usess,
271 uchan, usess->consumer,
272 uchan->attr.overwrite,
273 discarded_events,
274 lost_packets);
275 if (ret < 0) {
276 goto end;
277 }
278 *discarded_events += uchan->per_pid_closed_app_discarded;
279 *lost_packets += uchan->per_pid_closed_app_lost;
280 } else {
281 ERR("Unsupported buffer type");
282 assert(0);
283 ret = -1;
284 goto end;
285 }
286
287 end:
288 return ret;
289 }
290
291 /*
292 * Fill lttng_channel array of all channels.
293 */
294 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
295 struct ltt_session *session, struct lttng_channel *channels,
296 struct lttng_channel_extended *chan_exts)
297 {
298 int i = 0, ret = 0;
299 struct ltt_kernel_channel *kchan;
300
301 DBG("Listing channels for session %s", session->name);
302
303 switch (domain) {
304 case LTTNG_DOMAIN_KERNEL:
305 /* Kernel channels */
306 if (session->kernel_session != NULL) {
307 cds_list_for_each_entry(kchan,
308 &session->kernel_session->channel_list.head, list) {
309 uint64_t discarded_events, lost_packets;
310 struct lttng_channel_extended *extended;
311
312 extended = (struct lttng_channel_extended *)
313 kchan->channel->attr.extended.ptr;
314
315 ret = get_kernel_runtime_stats(session, kchan,
316 &discarded_events, &lost_packets);
317 if (ret < 0) {
318 goto end;
319 }
320 /* Copy lttng_channel struct to array */
321 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
322 channels[i].enabled = kchan->enabled;
323 chan_exts[i].discarded_events =
324 discarded_events;
325 chan_exts[i].lost_packets = lost_packets;
326 chan_exts[i].monitor_timer_interval =
327 extended->monitor_timer_interval;
328 chan_exts[i].blocking_timeout = 0;
329 i++;
330 }
331 }
332 break;
333 case LTTNG_DOMAIN_UST:
334 {
335 struct lttng_ht_iter iter;
336 struct ltt_ust_channel *uchan;
337
338 rcu_read_lock();
339 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
340 &iter.iter, uchan, node.node) {
341 uint64_t discarded_events = 0, lost_packets = 0;
342
343 if (lttng_strncpy(channels[i].name, uchan->name,
344 LTTNG_SYMBOL_NAME_LEN)) {
345 break;
346 }
347 channels[i].attr.overwrite = uchan->attr.overwrite;
348 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
349 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
350 channels[i].attr.switch_timer_interval =
351 uchan->attr.switch_timer_interval;
352 channels[i].attr.read_timer_interval =
353 uchan->attr.read_timer_interval;
354 channels[i].enabled = uchan->enabled;
355 channels[i].attr.tracefile_size = uchan->tracefile_size;
356 channels[i].attr.tracefile_count = uchan->tracefile_count;
357
358 /*
359 * Map enum lttng_ust_output to enum lttng_event_output.
360 */
361 switch (uchan->attr.output) {
362 case LTTNG_UST_MMAP:
363 channels[i].attr.output = LTTNG_EVENT_MMAP;
364 break;
365 default:
366 /*
367 * LTTNG_UST_MMAP is the only supported UST
368 * output mode.
369 */
370 assert(0);
371 break;
372 }
373
374 chan_exts[i].monitor_timer_interval =
375 uchan->monitor_timer_interval;
376 chan_exts[i].blocking_timeout =
377 uchan->attr.u.s.blocking_timeout;
378
379 ret = get_ust_runtime_stats(session, uchan,
380 &discarded_events, &lost_packets);
381 if (ret < 0) {
382 break;
383 }
384 chan_exts[i].discarded_events = discarded_events;
385 chan_exts[i].lost_packets = lost_packets;
386 i++;
387 }
388 rcu_read_unlock();
389 break;
390 }
391 default:
392 break;
393 }
394
395 end:
396 if (ret < 0) {
397 return -LTTNG_ERR_FATAL;
398 } else {
399 return LTTNG_OK;
400 }
401 }
402
403 static int increment_extended_len(const char *filter_expression,
404 struct lttng_event_exclusion *exclusion,
405 const struct lttng_userspace_probe_location *probe_location,
406 size_t *extended_len)
407 {
408 int ret = 0;
409
410 *extended_len += sizeof(struct lttcomm_event_extended_header);
411
412 if (filter_expression) {
413 *extended_len += strlen(filter_expression) + 1;
414 }
415
416 if (exclusion) {
417 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
418 }
419
420 if (probe_location) {
421 ret = lttng_userspace_probe_location_serialize(probe_location,
422 NULL, NULL);
423 if (ret < 0) {
424 goto end;
425 }
426 *extended_len += ret;
427 }
428 ret = 0;
429 end:
430 return ret;
431 }
432
433 static int append_extended_info(const char *filter_expression,
434 struct lttng_event_exclusion *exclusion,
435 struct lttng_userspace_probe_location *probe_location,
436 void **extended_at)
437 {
438 int ret = 0;
439 size_t filter_len = 0;
440 size_t nb_exclusions = 0;
441 size_t userspace_probe_location_len = 0;
442 struct lttng_dynamic_buffer location_buffer;
443 struct lttcomm_event_extended_header extended_header;
444
445 if (filter_expression) {
446 filter_len = strlen(filter_expression) + 1;
447 }
448
449 if (exclusion) {
450 nb_exclusions = exclusion->count;
451 }
452
453 if (probe_location) {
454 lttng_dynamic_buffer_init(&location_buffer);
455 ret = lttng_userspace_probe_location_serialize(probe_location,
456 &location_buffer, NULL);
457 if (ret < 0) {
458 ret = -1;
459 goto end;
460 }
461 userspace_probe_location_len = location_buffer.size;
462 }
463
464 /* Set header fields */
465 extended_header.filter_len = filter_len;
466 extended_header.nb_exclusions = nb_exclusions;
467 extended_header.userspace_probe_location_len = userspace_probe_location_len;
468
469 /* Copy header */
470 memcpy(*extended_at, &extended_header, sizeof(extended_header));
471 *extended_at += sizeof(extended_header);
472
473 /* Copy filter string */
474 if (filter_expression) {
475 memcpy(*extended_at, filter_expression, filter_len);
476 *extended_at += filter_len;
477 }
478
479 /* Copy exclusion names */
480 if (exclusion) {
481 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
482
483 memcpy(*extended_at, &exclusion->names, len);
484 *extended_at += len;
485 }
486
487 if (probe_location) {
488 memcpy(*extended_at, location_buffer.data, location_buffer.size);
489 *extended_at += location_buffer.size;
490 lttng_dynamic_buffer_reset(&location_buffer);
491 }
492 ret = 0;
493 end:
494 return ret;
495 }
496
497 /*
498 * Create a list of agent domain events.
499 *
500 * Return number of events in list on success or else a negative value.
501 */
502 static int list_lttng_agent_events(struct agent *agt,
503 struct lttng_event **events, size_t *total_size)
504 {
505 int i = 0, ret = 0;
506 unsigned int nb_event = 0;
507 struct agent_event *event;
508 struct lttng_event *tmp_events = NULL;
509 struct lttng_ht_iter iter;
510 size_t extended_len = 0;
511 void *extended_at;
512
513 assert(agt);
514 assert(events);
515
516 DBG3("Listing agent events");
517
518 rcu_read_lock();
519 nb_event = lttng_ht_get_count(agt->events);
520 rcu_read_unlock();
521 if (nb_event == 0) {
522 ret = nb_event;
523 *total_size = 0;
524 goto error;
525 }
526
527 /* Compute required extended infos size */
528 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
529
530 /*
531 * This is only valid because the commands which add events are
532 * processed in the same thread as the listing.
533 */
534 rcu_read_lock();
535 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
536 ret = increment_extended_len(event->filter_expression, NULL, NULL,
537 &extended_len);
538 if (ret) {
539 DBG("Error computing the length of extended info message");
540 ret = -LTTNG_ERR_FATAL;
541 goto error;
542 }
543 }
544 rcu_read_unlock();
545
546 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
547 tmp_events = zmalloc(*total_size);
548 if (!tmp_events) {
549 PERROR("zmalloc agent events session");
550 ret = -LTTNG_ERR_FATAL;
551 goto error;
552 }
553
554 extended_at = ((uint8_t *) tmp_events) +
555 nb_event * sizeof(struct lttng_event);
556
557 rcu_read_lock();
558 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
559 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
560 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
561 tmp_events[i].enabled = event->enabled;
562 tmp_events[i].loglevel = event->loglevel_value;
563 tmp_events[i].loglevel_type = event->loglevel_type;
564 i++;
565
566 /* Append extended info */
567 ret = append_extended_info(event->filter_expression, NULL, NULL,
568 &extended_at);
569 if (ret) {
570 DBG("Error appending extended info message");
571 ret = -LTTNG_ERR_FATAL;
572 goto error;
573 }
574 }
575
576 *events = tmp_events;
577 ret = nb_event;
578 assert(nb_event == i);
579
580 end:
581 rcu_read_unlock();
582 return ret;
583 error:
584 free(tmp_events);
585 goto end;
586 }
587
588 /*
589 * Create a list of ust global domain events.
590 */
591 static int list_lttng_ust_global_events(char *channel_name,
592 struct ltt_ust_domain_global *ust_global,
593 struct lttng_event **events, size_t *total_size)
594 {
595 int i = 0, ret = 0;
596 unsigned int nb_event = 0;
597 struct lttng_ht_iter iter;
598 struct lttng_ht_node_str *node;
599 struct ltt_ust_channel *uchan;
600 struct ltt_ust_event *uevent;
601 struct lttng_event *tmp;
602 size_t extended_len = 0;
603 void *extended_at;
604
605 DBG("Listing UST global events for channel %s", channel_name);
606
607 rcu_read_lock();
608
609 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
610 node = lttng_ht_iter_get_node_str(&iter);
611 if (node == NULL) {
612 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
613 goto end;
614 }
615
616 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
617
618 nb_event = lttng_ht_get_count(uchan->events);
619 if (nb_event == 0) {
620 ret = nb_event;
621 *total_size = 0;
622 goto end;
623 }
624
625 DBG3("Listing UST global %d events", nb_event);
626
627 /* Compute required extended infos size */
628 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
629 if (uevent->internal) {
630 nb_event--;
631 continue;
632 }
633
634 ret = increment_extended_len(uevent->filter_expression,
635 uevent->exclusion, NULL, &extended_len);
636 if (ret) {
637 DBG("Error computing the length of extended info message");
638 ret = -LTTNG_ERR_FATAL;
639 goto end;
640 }
641 }
642 if (nb_event == 0) {
643 /* All events are internal, skip. */
644 ret = 0;
645 *total_size = 0;
646 goto end;
647 }
648
649 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
650 tmp = zmalloc(*total_size);
651 if (tmp == NULL) {
652 ret = -LTTNG_ERR_FATAL;
653 goto end;
654 }
655
656 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
657
658 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
659 if (uevent->internal) {
660 /* This event should remain hidden from clients */
661 continue;
662 }
663 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
664 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
665 tmp[i].enabled = uevent->enabled;
666
667 switch (uevent->attr.instrumentation) {
668 case LTTNG_UST_TRACEPOINT:
669 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
670 break;
671 case LTTNG_UST_PROBE:
672 tmp[i].type = LTTNG_EVENT_PROBE;
673 break;
674 case LTTNG_UST_FUNCTION:
675 tmp[i].type = LTTNG_EVENT_FUNCTION;
676 break;
677 }
678
679 tmp[i].loglevel = uevent->attr.loglevel;
680 switch (uevent->attr.loglevel_type) {
681 case LTTNG_UST_LOGLEVEL_ALL:
682 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
683 break;
684 case LTTNG_UST_LOGLEVEL_RANGE:
685 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
686 break;
687 case LTTNG_UST_LOGLEVEL_SINGLE:
688 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
689 break;
690 }
691 if (uevent->filter) {
692 tmp[i].filter = 1;
693 }
694 if (uevent->exclusion) {
695 tmp[i].exclusion = 1;
696 }
697 i++;
698
699 /* Append extended info */
700 ret = append_extended_info(uevent->filter_expression,
701 uevent->exclusion, NULL, &extended_at);
702 if (ret) {
703 DBG("Error appending extended info message");
704 ret = -LTTNG_ERR_FATAL;
705 goto end;
706 }
707 }
708
709 ret = nb_event;
710 *events = tmp;
711 end:
712 rcu_read_unlock();
713 return ret;
714 }
715
716 /*
717 * Fill lttng_event array of all kernel events in the channel.
718 */
719 static int list_lttng_kernel_events(char *channel_name,
720 struct ltt_kernel_session *kernel_session,
721 struct lttng_event **events, size_t *total_size)
722 {
723 int i = 0, ret;
724 unsigned int nb_event;
725 struct ltt_kernel_event *event;
726 struct ltt_kernel_channel *kchan;
727 size_t extended_len = 0;
728 void *extended_at;
729
730 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
731 if (kchan == NULL) {
732 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
733 goto error;
734 }
735
736 nb_event = kchan->event_count;
737
738 DBG("Listing events for channel %s", kchan->channel->name);
739
740 if (nb_event == 0) {
741 *total_size = 0;
742 *events = NULL;
743 goto end;
744 }
745
746 /* Compute required extended infos size */
747 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
748 ret = increment_extended_len(event->filter_expression, NULL,
749 event->userspace_probe_location,
750 &extended_len);
751 if (ret) {
752 DBG("Error computing the length of extended info message");
753 ret = -LTTNG_ERR_FATAL;
754 goto error;
755 }
756 }
757
758 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
759 *events = zmalloc(*total_size);
760 if (*events == NULL) {
761 ret = -LTTNG_ERR_FATAL;
762 goto error;
763 }
764
765 extended_at = ((void *) *events) +
766 nb_event * sizeof(struct lttng_event);
767
768 /* Kernel channels */
769 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
770 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
771 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
772 (*events)[i].enabled = event->enabled;
773 (*events)[i].filter =
774 (unsigned char) !!event->filter_expression;
775
776 switch (event->event->instrumentation) {
777 case LTTNG_KERNEL_TRACEPOINT:
778 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
779 break;
780 case LTTNG_KERNEL_KRETPROBE:
781 (*events)[i].type = LTTNG_EVENT_FUNCTION;
782 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
783 sizeof(struct lttng_kernel_kprobe));
784 break;
785 case LTTNG_KERNEL_KPROBE:
786 (*events)[i].type = LTTNG_EVENT_PROBE;
787 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
788 sizeof(struct lttng_kernel_kprobe));
789 break;
790 case LTTNG_KERNEL_UPROBE:
791 (*events)[i].type = LTTNG_EVENT_USERSPACE_PROBE;
792 break;
793 case LTTNG_KERNEL_FUNCTION:
794 (*events)[i].type = LTTNG_EVENT_FUNCTION;
795 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
796 sizeof(struct lttng_kernel_function));
797 break;
798 case LTTNG_KERNEL_NOOP:
799 (*events)[i].type = LTTNG_EVENT_NOOP;
800 break;
801 case LTTNG_KERNEL_SYSCALL:
802 (*events)[i].type = LTTNG_EVENT_SYSCALL;
803 break;
804 case LTTNG_KERNEL_ALL:
805 /* fall-through. */
806 default:
807 assert(0);
808 break;
809 }
810 i++;
811
812 /* Append extended info */
813 ret = append_extended_info(event->filter_expression, NULL,
814 event->userspace_probe_location, &extended_at);
815 if (ret) {
816 DBG("Error appending extended info message");
817 ret = -LTTNG_ERR_FATAL;
818 goto error;
819 }
820 }
821
822 end:
823 return nb_event;
824
825 error:
826 /* Negate the error code to differentiate the size from an error */
827 return -ret;
828 }
829
830 /*
831 * Add URI so the consumer output object. Set the correct path depending on the
832 * domain adding the default trace directory.
833 */
834 static enum lttng_error_code add_uri_to_consumer(
835 const struct ltt_session *session,
836 struct consumer_output *consumer,
837 struct lttng_uri *uri, enum lttng_domain_type domain)
838 {
839 int ret;
840 enum lttng_error_code ret_code = LTTNG_OK;
841
842 assert(uri);
843
844 if (consumer == NULL) {
845 DBG("No consumer detected. Don't add URI. Stopping.");
846 ret_code = LTTNG_ERR_NO_CONSUMER;
847 goto error;
848 }
849
850 switch (domain) {
851 case LTTNG_DOMAIN_KERNEL:
852 ret = lttng_strncpy(consumer->domain_subdir,
853 DEFAULT_KERNEL_TRACE_DIR,
854 sizeof(consumer->domain_subdir));
855 break;
856 case LTTNG_DOMAIN_UST:
857 ret = lttng_strncpy(consumer->domain_subdir,
858 DEFAULT_UST_TRACE_DIR,
859 sizeof(consumer->domain_subdir));
860 break;
861 default:
862 /*
863 * This case is possible is we try to add the URI to the global
864 * tracing session consumer object which in this case there is
865 * no subdir.
866 */
867 memset(consumer->domain_subdir, 0,
868 sizeof(consumer->domain_subdir));
869 ret = 0;
870 }
871 if (ret) {
872 ERR("Failed to initialize consumer output domain subdirectory");
873 ret_code = LTTNG_ERR_FATAL;
874 goto error;
875 }
876
877 switch (uri->dtype) {
878 case LTTNG_DST_IPV4:
879 case LTTNG_DST_IPV6:
880 DBG2("Setting network URI to consumer");
881
882 if (consumer->type == CONSUMER_DST_NET) {
883 if ((uri->stype == LTTNG_STREAM_CONTROL &&
884 consumer->dst.net.control_isset) ||
885 (uri->stype == LTTNG_STREAM_DATA &&
886 consumer->dst.net.data_isset)) {
887 ret_code = LTTNG_ERR_URL_EXIST;
888 goto error;
889 }
890 } else {
891 memset(&consumer->dst, 0, sizeof(consumer->dst));
892 }
893
894 /* Set URI into consumer output object */
895 ret = consumer_set_network_uri(session, consumer, uri);
896 if (ret < 0) {
897 ret_code = -ret;
898 goto error;
899 } else if (ret == 1) {
900 /*
901 * URI was the same in the consumer so we do not append the subdir
902 * again so to not duplicate output dir.
903 */
904 ret_code = LTTNG_OK;
905 goto error;
906 }
907 break;
908 case LTTNG_DST_PATH:
909 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
910 ret_code = LTTNG_ERR_INVALID;
911 goto error;
912 }
913 DBG2("Setting trace directory path from URI to %s",
914 uri->dst.path);
915 memset(&consumer->dst, 0, sizeof(consumer->dst));
916
917 ret = lttng_strncpy(consumer->dst.session_root_path,
918 uri->dst.path,
919 sizeof(consumer->dst.session_root_path));
920 if (ret) {
921 ret_code = LTTNG_ERR_FATAL;
922 goto error;
923 }
924 consumer->type = CONSUMER_DST_LOCAL;
925 break;
926 }
927
928 ret_code = LTTNG_OK;
929 error:
930 return ret_code;
931 }
932
933 /*
934 * Init tracing by creating trace directory and sending fds kernel consumer.
935 */
936 static int init_kernel_tracing(struct ltt_kernel_session *session)
937 {
938 int ret = 0;
939 struct lttng_ht_iter iter;
940 struct consumer_socket *socket;
941
942 assert(session);
943
944 rcu_read_lock();
945
946 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
947 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
948 socket, node.node) {
949 pthread_mutex_lock(socket->lock);
950 ret = kernel_consumer_send_session(socket, session);
951 pthread_mutex_unlock(socket->lock);
952 if (ret < 0) {
953 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
954 goto error;
955 }
956 }
957 }
958
959 error:
960 rcu_read_unlock();
961 return ret;
962 }
963
964 /*
965 * Create a socket to the relayd using the URI.
966 *
967 * On success, the relayd_sock pointer is set to the created socket.
968 * Else, it remains untouched and an LTTng error code is returned.
969 */
970 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
971 struct lttcomm_relayd_sock **relayd_sock,
972 struct consumer_output *consumer)
973 {
974 int ret;
975 enum lttng_error_code status = LTTNG_OK;
976 struct lttcomm_relayd_sock *rsock;
977
978 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
979 RELAYD_VERSION_COMM_MINOR);
980 if (!rsock) {
981 status = LTTNG_ERR_FATAL;
982 goto error;
983 }
984
985 /*
986 * Connect to relayd so we can proceed with a session creation. This call
987 * can possibly block for an arbitrary amount of time to set the health
988 * state to be in poll execution.
989 */
990 health_poll_entry();
991 ret = relayd_connect(rsock);
992 health_poll_exit();
993 if (ret < 0) {
994 ERR("Unable to reach lttng-relayd");
995 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
996 goto free_sock;
997 }
998
999 /* Create socket for control stream. */
1000 if (uri->stype == LTTNG_STREAM_CONTROL) {
1001 DBG3("Creating relayd stream socket from URI");
1002
1003 /* Check relayd version */
1004 ret = relayd_version_check(rsock);
1005 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
1006 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
1007 goto close_sock;
1008 } else if (ret < 0) {
1009 ERR("Unable to reach lttng-relayd");
1010 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1011 goto close_sock;
1012 }
1013 consumer->relay_major_version = rsock->major;
1014 consumer->relay_minor_version = rsock->minor;
1015 } else if (uri->stype == LTTNG_STREAM_DATA) {
1016 DBG3("Creating relayd data socket from URI");
1017 } else {
1018 /* Command is not valid */
1019 ERR("Relayd invalid stream type: %d", uri->stype);
1020 status = LTTNG_ERR_INVALID;
1021 goto close_sock;
1022 }
1023
1024 *relayd_sock = rsock;
1025
1026 return status;
1027
1028 close_sock:
1029 /* The returned value is not useful since we are on an error path. */
1030 (void) relayd_close(rsock);
1031 free_sock:
1032 free(rsock);
1033 error:
1034 return status;
1035 }
1036
1037 /*
1038 * Connect to the relayd using URI and send the socket to the right consumer.
1039 *
1040 * The consumer socket lock must be held by the caller.
1041 *
1042 * Returns LTTNG_OK on success or an LTTng error code on failure.
1043 */
1044 static enum lttng_error_code send_consumer_relayd_socket(
1045 unsigned int session_id,
1046 struct lttng_uri *relayd_uri,
1047 struct consumer_output *consumer,
1048 struct consumer_socket *consumer_sock,
1049 const char *session_name, const char *hostname,
1050 const char *base_path, int session_live_timer,
1051 const uint64_t *current_chunk_id,
1052 time_t session_creation_time,
1053 bool session_name_contains_creation_time)
1054 {
1055 int ret;
1056 struct lttcomm_relayd_sock *rsock = NULL;
1057 enum lttng_error_code status;
1058
1059 /* Connect to relayd and make version check if uri is the control. */
1060 status = create_connect_relayd(relayd_uri, &rsock, consumer);
1061 if (status != LTTNG_OK) {
1062 goto relayd_comm_error;
1063 }
1064 assert(rsock);
1065
1066 /* Set the network sequence index if not set. */
1067 if (consumer->net_seq_index == (uint64_t) -1ULL) {
1068 pthread_mutex_lock(&relayd_net_seq_idx_lock);
1069 /*
1070 * Increment net_seq_idx because we are about to transfer the
1071 * new relayd socket to the consumer.
1072 * Assign unique key so the consumer can match streams.
1073 */
1074 consumer->net_seq_index = ++relayd_net_seq_idx;
1075 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
1076 }
1077
1078 /* Send relayd socket to consumer. */
1079 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
1080 relayd_uri->stype, session_id,
1081 session_name, hostname, base_path,
1082 session_live_timer, current_chunk_id,
1083 session_creation_time, session_name_contains_creation_time);
1084 if (ret < 0) {
1085 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
1086 goto close_sock;
1087 }
1088
1089 /* Flag that the corresponding socket was sent. */
1090 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
1091 consumer_sock->control_sock_sent = 1;
1092 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
1093 consumer_sock->data_sock_sent = 1;
1094 }
1095
1096 /*
1097 * Close socket which was dup on the consumer side. The session daemon does
1098 * NOT keep track of the relayd socket(s) once transfer to the consumer.
1099 */
1100
1101 close_sock:
1102 if (status != LTTNG_OK) {
1103 /*
1104 * The consumer output for this session should not be used anymore
1105 * since the relayd connection failed thus making any tracing or/and
1106 * streaming not usable.
1107 */
1108 consumer->enabled = 0;
1109 }
1110 (void) relayd_close(rsock);
1111 free(rsock);
1112
1113 relayd_comm_error:
1114 return status;
1115 }
1116
1117 /*
1118 * Send both relayd sockets to a specific consumer and domain. This is a
1119 * helper function to facilitate sending the information to the consumer for a
1120 * session.
1121 *
1122 * The consumer socket lock must be held by the caller.
1123 *
1124 * Returns LTTNG_OK, or an LTTng error code on failure.
1125 */
1126 static enum lttng_error_code send_consumer_relayd_sockets(
1127 enum lttng_domain_type domain,
1128 unsigned int session_id, struct consumer_output *consumer,
1129 struct consumer_socket *sock, const char *session_name,
1130 const char *hostname, const char *base_path, int session_live_timer,
1131 const uint64_t *current_chunk_id, time_t session_creation_time,
1132 bool session_name_contains_creation_time)
1133 {
1134 enum lttng_error_code status = LTTNG_OK;
1135
1136 assert(consumer);
1137 assert(sock);
1138
1139 /* Sending control relayd socket. */
1140 if (!sock->control_sock_sent) {
1141 status = send_consumer_relayd_socket(session_id,
1142 &consumer->dst.net.control, consumer, sock,
1143 session_name, hostname, base_path, session_live_timer,
1144 current_chunk_id, session_creation_time,
1145 session_name_contains_creation_time);
1146 if (status != LTTNG_OK) {
1147 goto error;
1148 }
1149 }
1150
1151 /* Sending data relayd socket. */
1152 if (!sock->data_sock_sent) {
1153 status = send_consumer_relayd_socket(session_id,
1154 &consumer->dst.net.data, consumer, sock,
1155 session_name, hostname, base_path, session_live_timer,
1156 current_chunk_id, session_creation_time,
1157 session_name_contains_creation_time);
1158 if (status != LTTNG_OK) {
1159 goto error;
1160 }
1161 }
1162
1163 error:
1164 return status;
1165 }
1166
1167 /*
1168 * Setup relayd connections for a tracing session. First creates the socket to
1169 * the relayd and send them to the right domain consumer. Consumer type MUST be
1170 * network.
1171 */
1172 int cmd_setup_relayd(struct ltt_session *session)
1173 {
1174 int ret = LTTNG_OK;
1175 struct ltt_ust_session *usess;
1176 struct ltt_kernel_session *ksess;
1177 struct consumer_socket *socket;
1178 struct lttng_ht_iter iter;
1179 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1180
1181 assert(session);
1182
1183 usess = session->ust_session;
1184 ksess = session->kernel_session;
1185
1186 DBG("Setting relayd for session %s", session->name);
1187
1188 if (session->current_trace_chunk) {
1189 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1190 session->current_trace_chunk, &current_chunk_id.value);
1191
1192 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1193 current_chunk_id.is_set = true;
1194 } else {
1195 ERR("Failed to get current trace chunk id");
1196 ret = LTTNG_ERR_UNK;
1197 goto error;
1198 }
1199 }
1200
1201 rcu_read_lock();
1202
1203 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1204 && usess->consumer->enabled) {
1205 /* For each consumer socket, send relayd sockets */
1206 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1207 socket, node.node) {
1208 pthread_mutex_lock(socket->lock);
1209 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1210 usess->consumer, socket,
1211 session->name, session->hostname,
1212 session->base_path,
1213 session->live_timer,
1214 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1215 session->creation_time,
1216 session->name_contains_creation_time);
1217 pthread_mutex_unlock(socket->lock);
1218 if (ret != LTTNG_OK) {
1219 goto error;
1220 }
1221 /* Session is now ready for network streaming. */
1222 session->net_handle = 1;
1223 }
1224 session->consumer->relay_major_version =
1225 usess->consumer->relay_major_version;
1226 session->consumer->relay_minor_version =
1227 usess->consumer->relay_minor_version;
1228 }
1229
1230 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1231 && ksess->consumer->enabled) {
1232 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1233 socket, node.node) {
1234 pthread_mutex_lock(socket->lock);
1235 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1236 ksess->consumer, socket,
1237 session->name, session->hostname,
1238 session->base_path,
1239 session->live_timer,
1240 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1241 session->creation_time,
1242 session->name_contains_creation_time);
1243 pthread_mutex_unlock(socket->lock);
1244 if (ret != LTTNG_OK) {
1245 goto error;
1246 }
1247 /* Session is now ready for network streaming. */
1248 session->net_handle = 1;
1249 }
1250 session->consumer->relay_major_version =
1251 ksess->consumer->relay_major_version;
1252 session->consumer->relay_minor_version =
1253 ksess->consumer->relay_minor_version;
1254 }
1255
1256 error:
1257 rcu_read_unlock();
1258 return ret;
1259 }
1260
1261 /*
1262 * Start a kernel session by opening all necessary streams.
1263 */
1264 static int start_kernel_session(struct ltt_kernel_session *ksess)
1265 {
1266 int ret;
1267 struct ltt_kernel_channel *kchan;
1268
1269 /* Open kernel metadata */
1270 if (ksess->metadata == NULL && ksess->output_traces) {
1271 ret = kernel_open_metadata(ksess);
1272 if (ret < 0) {
1273 ret = LTTNG_ERR_KERN_META_FAIL;
1274 goto error;
1275 }
1276 }
1277
1278 /* Open kernel metadata stream */
1279 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1280 ret = kernel_open_metadata_stream(ksess);
1281 if (ret < 0) {
1282 ERR("Kernel create metadata stream failed");
1283 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1284 goto error;
1285 }
1286 }
1287
1288 /* For each channel */
1289 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1290 if (kchan->stream_count == 0) {
1291 ret = kernel_open_channel_stream(kchan);
1292 if (ret < 0) {
1293 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1294 goto error;
1295 }
1296 /* Update the stream global counter */
1297 ksess->stream_count_global += ret;
1298 }
1299 }
1300
1301 /* Setup kernel consumer socket and send fds to it */
1302 ret = init_kernel_tracing(ksess);
1303 if (ret != 0) {
1304 ret = LTTNG_ERR_KERN_START_FAIL;
1305 goto error;
1306 }
1307
1308 /* This start the kernel tracing */
1309 ret = kernel_start_session(ksess);
1310 if (ret < 0) {
1311 ret = LTTNG_ERR_KERN_START_FAIL;
1312 goto error;
1313 }
1314
1315 /* Quiescent wait after starting trace */
1316 kernel_wait_quiescent();
1317
1318 ksess->active = 1;
1319
1320 ret = LTTNG_OK;
1321
1322 error:
1323 return ret;
1324 }
1325
1326 /*
1327 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1328 */
1329 int cmd_disable_channel(struct ltt_session *session,
1330 enum lttng_domain_type domain, char *channel_name)
1331 {
1332 int ret;
1333 struct ltt_ust_session *usess;
1334
1335 usess = session->ust_session;
1336
1337 rcu_read_lock();
1338
1339 switch (domain) {
1340 case LTTNG_DOMAIN_KERNEL:
1341 {
1342 ret = channel_kernel_disable(session->kernel_session,
1343 channel_name);
1344 if (ret != LTTNG_OK) {
1345 goto error;
1346 }
1347
1348 kernel_wait_quiescent();
1349 break;
1350 }
1351 case LTTNG_DOMAIN_UST:
1352 {
1353 struct ltt_ust_channel *uchan;
1354 struct lttng_ht *chan_ht;
1355
1356 chan_ht = usess->domain_global.channels;
1357
1358 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1359 if (uchan == NULL) {
1360 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1361 goto error;
1362 }
1363
1364 ret = channel_ust_disable(usess, uchan);
1365 if (ret != LTTNG_OK) {
1366 goto error;
1367 }
1368 break;
1369 }
1370 default:
1371 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1372 goto error;
1373 }
1374
1375 ret = LTTNG_OK;
1376
1377 error:
1378 rcu_read_unlock();
1379 return ret;
1380 }
1381
1382 /*
1383 * Command LTTNG_TRACK_PID processed by the client thread.
1384 *
1385 * Called with session lock held.
1386 */
1387 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1388 int pid)
1389 {
1390 int ret;
1391
1392 rcu_read_lock();
1393
1394 switch (domain) {
1395 case LTTNG_DOMAIN_KERNEL:
1396 {
1397 struct ltt_kernel_session *ksess;
1398
1399 ksess = session->kernel_session;
1400
1401 ret = kernel_track_pid(ksess, pid);
1402 if (ret != LTTNG_OK) {
1403 goto error;
1404 }
1405
1406 kernel_wait_quiescent();
1407 break;
1408 }
1409 case LTTNG_DOMAIN_UST:
1410 {
1411 struct ltt_ust_session *usess;
1412
1413 usess = session->ust_session;
1414
1415 ret = trace_ust_track_pid(usess, pid);
1416 if (ret != LTTNG_OK) {
1417 goto error;
1418 }
1419 break;
1420 }
1421 default:
1422 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1423 goto error;
1424 }
1425
1426 ret = LTTNG_OK;
1427
1428 error:
1429 rcu_read_unlock();
1430 return ret;
1431 }
1432
1433 /*
1434 * Command LTTNG_UNTRACK_PID processed by the client thread.
1435 *
1436 * Called with session lock held.
1437 */
1438 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1439 int pid)
1440 {
1441 int ret;
1442
1443 rcu_read_lock();
1444
1445 switch (domain) {
1446 case LTTNG_DOMAIN_KERNEL:
1447 {
1448 struct ltt_kernel_session *ksess;
1449
1450 ksess = session->kernel_session;
1451
1452 ret = kernel_untrack_pid(ksess, pid);
1453 if (ret != LTTNG_OK) {
1454 goto error;
1455 }
1456
1457 kernel_wait_quiescent();
1458 break;
1459 }
1460 case LTTNG_DOMAIN_UST:
1461 {
1462 struct ltt_ust_session *usess;
1463
1464 usess = session->ust_session;
1465
1466 ret = trace_ust_untrack_pid(usess, pid);
1467 if (ret != LTTNG_OK) {
1468 goto error;
1469 }
1470 break;
1471 }
1472 default:
1473 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1474 goto error;
1475 }
1476
1477 ret = LTTNG_OK;
1478
1479 error:
1480 rcu_read_unlock();
1481 return ret;
1482 }
1483
1484 /*
1485 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1486 *
1487 * The wpipe arguments is used as a notifier for the kernel thread.
1488 */
1489 int cmd_enable_channel(struct ltt_session *session,
1490 const struct lttng_domain *domain, const struct lttng_channel *_attr, int wpipe)
1491 {
1492 int ret;
1493 struct ltt_ust_session *usess = session->ust_session;
1494 struct lttng_ht *chan_ht;
1495 size_t len;
1496 struct lttng_channel attr;
1497
1498 assert(session);
1499 assert(_attr);
1500 assert(domain);
1501
1502 attr = *_attr;
1503 len = lttng_strnlen(attr.name, sizeof(attr.name));
1504
1505 /* Validate channel name */
1506 if (attr.name[0] == '.' ||
1507 memchr(attr.name, '/', len) != NULL) {
1508 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1509 goto end;
1510 }
1511
1512 DBG("Enabling channel %s for session %s", attr.name, session->name);
1513
1514 rcu_read_lock();
1515
1516 /*
1517 * Don't try to enable a channel if the session has been started at
1518 * some point in time before. The tracer does not allow it.
1519 */
1520 if (session->has_been_started) {
1521 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1522 goto error;
1523 }
1524
1525 /*
1526 * If the session is a live session, remove the switch timer, the
1527 * live timer does the same thing but sends also synchronisation
1528 * beacons for inactive streams.
1529 */
1530 if (session->live_timer > 0) {
1531 attr.attr.live_timer_interval = session->live_timer;
1532 attr.attr.switch_timer_interval = 0;
1533 }
1534
1535 /* Check for feature support */
1536 switch (domain->type) {
1537 case LTTNG_DOMAIN_KERNEL:
1538 {
1539 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1540 /* Sampling position of buffer is not supported */
1541 WARN("Kernel tracer does not support buffer monitoring. "
1542 "Setting the monitor interval timer to 0 "
1543 "(disabled) for channel '%s' of session '%s'",
1544 attr.name, session->name);
1545 lttng_channel_set_monitor_timer_interval(&attr, 0);
1546 }
1547 break;
1548 }
1549 case LTTNG_DOMAIN_UST:
1550 break;
1551 case LTTNG_DOMAIN_JUL:
1552 case LTTNG_DOMAIN_LOG4J:
1553 case LTTNG_DOMAIN_PYTHON:
1554 if (!agent_tracing_is_enabled()) {
1555 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1556 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1557 goto error;
1558 }
1559 break;
1560 default:
1561 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1562 goto error;
1563 }
1564
1565 switch (domain->type) {
1566 case LTTNG_DOMAIN_KERNEL:
1567 {
1568 struct ltt_kernel_channel *kchan;
1569
1570 kchan = trace_kernel_get_channel_by_name(attr.name,
1571 session->kernel_session);
1572 if (kchan == NULL) {
1573 if (session->snapshot.nb_output > 0 ||
1574 session->snapshot_mode) {
1575 /* Enforce mmap output for snapshot sessions. */
1576 attr.attr.output = LTTNG_EVENT_MMAP;
1577 }
1578 ret = channel_kernel_create(session->kernel_session, &attr, wpipe);
1579 if (attr.name[0] != '\0') {
1580 session->kernel_session->has_non_default_channel = 1;
1581 }
1582 } else {
1583 ret = channel_kernel_enable(session->kernel_session, kchan);
1584 }
1585
1586 if (ret != LTTNG_OK) {
1587 goto error;
1588 }
1589
1590 kernel_wait_quiescent();
1591 break;
1592 }
1593 case LTTNG_DOMAIN_UST:
1594 case LTTNG_DOMAIN_JUL:
1595 case LTTNG_DOMAIN_LOG4J:
1596 case LTTNG_DOMAIN_PYTHON:
1597 {
1598 struct ltt_ust_channel *uchan;
1599
1600 /*
1601 * FIXME
1602 *
1603 * Current agent implementation limitations force us to allow
1604 * only one channel at once in "agent" subdomains. Each
1605 * subdomain has a default channel name which must be strictly
1606 * adhered to.
1607 */
1608 if (domain->type == LTTNG_DOMAIN_JUL) {
1609 if (strncmp(attr.name, DEFAULT_JUL_CHANNEL_NAME,
1610 LTTNG_SYMBOL_NAME_LEN)) {
1611 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1612 goto error;
1613 }
1614 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1615 if (strncmp(attr.name, DEFAULT_LOG4J_CHANNEL_NAME,
1616 LTTNG_SYMBOL_NAME_LEN)) {
1617 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1618 goto error;
1619 }
1620 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1621 if (strncmp(attr.name, DEFAULT_PYTHON_CHANNEL_NAME,
1622 LTTNG_SYMBOL_NAME_LEN)) {
1623 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1624 goto error;
1625 }
1626 }
1627
1628 chan_ht = usess->domain_global.channels;
1629
1630 uchan = trace_ust_find_channel_by_name(chan_ht, attr.name);
1631 if (uchan == NULL) {
1632 ret = channel_ust_create(usess, &attr, domain->buf_type);
1633 if (attr.name[0] != '\0') {
1634 usess->has_non_default_channel = 1;
1635 }
1636 } else {
1637 ret = channel_ust_enable(usess, uchan);
1638 }
1639 break;
1640 }
1641 default:
1642 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1643 goto error;
1644 }
1645
1646 if (ret == LTTNG_OK && attr.attr.output != LTTNG_EVENT_MMAP) {
1647 session->has_non_mmap_channel = true;
1648 }
1649 error:
1650 rcu_read_unlock();
1651 end:
1652 return ret;
1653 }
1654
1655 /*
1656 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1657 */
1658 int cmd_disable_event(struct ltt_session *session,
1659 enum lttng_domain_type domain, const char *channel_name,
1660 const struct lttng_event *event)
1661 {
1662 int ret;
1663 const char *event_name;
1664
1665 DBG("Disable event command for event \'%s\'", event->name);
1666
1667 event_name = event->name;
1668
1669 /* Error out on unhandled search criteria */
1670 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1671 || event->pid || event->filter || event->exclusion) {
1672 ret = LTTNG_ERR_UNK;
1673 goto error;
1674 }
1675
1676 rcu_read_lock();
1677
1678 switch (domain) {
1679 case LTTNG_DOMAIN_KERNEL:
1680 {
1681 struct ltt_kernel_channel *kchan;
1682 struct ltt_kernel_session *ksess;
1683
1684 ksess = session->kernel_session;
1685
1686 /*
1687 * If a non-default channel has been created in the
1688 * session, explicitely require that -c chan_name needs
1689 * to be provided.
1690 */
1691 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1692 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1693 goto error_unlock;
1694 }
1695
1696 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1697 if (kchan == NULL) {
1698 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1699 goto error_unlock;
1700 }
1701
1702 switch (event->type) {
1703 case LTTNG_EVENT_ALL:
1704 case LTTNG_EVENT_TRACEPOINT:
1705 case LTTNG_EVENT_SYSCALL:
1706 case LTTNG_EVENT_PROBE:
1707 case LTTNG_EVENT_FUNCTION:
1708 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1709 if (event_name[0] == '\0') {
1710 ret = event_kernel_disable_event(kchan,
1711 NULL, event->type);
1712 } else {
1713 ret = event_kernel_disable_event(kchan,
1714 event_name, event->type);
1715 }
1716 if (ret != LTTNG_OK) {
1717 goto error_unlock;
1718 }
1719 break;
1720 default:
1721 ret = LTTNG_ERR_UNK;
1722 goto error_unlock;
1723 }
1724
1725 kernel_wait_quiescent();
1726 break;
1727 }
1728 case LTTNG_DOMAIN_UST:
1729 {
1730 struct ltt_ust_channel *uchan;
1731 struct ltt_ust_session *usess;
1732
1733 usess = session->ust_session;
1734
1735 if (validate_ust_event_name(event_name)) {
1736 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1737 goto error_unlock;
1738 }
1739
1740 /*
1741 * If a non-default channel has been created in the
1742 * session, explicitly require that -c chan_name needs
1743 * to be provided.
1744 */
1745 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1746 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1747 goto error_unlock;
1748 }
1749
1750 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1751 channel_name);
1752 if (uchan == NULL) {
1753 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1754 goto error_unlock;
1755 }
1756
1757 switch (event->type) {
1758 case LTTNG_EVENT_ALL:
1759 /*
1760 * An empty event name means that everything
1761 * should be disabled.
1762 */
1763 if (event->name[0] == '\0') {
1764 ret = event_ust_disable_all_tracepoints(usess, uchan);
1765 } else {
1766 ret = event_ust_disable_tracepoint(usess, uchan,
1767 event_name);
1768 }
1769 if (ret != LTTNG_OK) {
1770 goto error_unlock;
1771 }
1772 break;
1773 default:
1774 ret = LTTNG_ERR_UNK;
1775 goto error_unlock;
1776 }
1777
1778 DBG3("Disable UST event %s in channel %s completed", event_name,
1779 channel_name);
1780 break;
1781 }
1782 case LTTNG_DOMAIN_LOG4J:
1783 case LTTNG_DOMAIN_JUL:
1784 case LTTNG_DOMAIN_PYTHON:
1785 {
1786 struct agent *agt;
1787 struct ltt_ust_session *usess = session->ust_session;
1788
1789 assert(usess);
1790
1791 switch (event->type) {
1792 case LTTNG_EVENT_ALL:
1793 break;
1794 default:
1795 ret = LTTNG_ERR_UNK;
1796 goto error_unlock;
1797 }
1798
1799 agt = trace_ust_find_agent(usess, domain);
1800 if (!agt) {
1801 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1802 goto error_unlock;
1803 }
1804 /*
1805 * An empty event name means that everything
1806 * should be disabled.
1807 */
1808 if (event->name[0] == '\0') {
1809 ret = event_agent_disable_all(usess, agt);
1810 } else {
1811 ret = event_agent_disable(usess, agt, event_name);
1812 }
1813 if (ret != LTTNG_OK) {
1814 goto error_unlock;
1815 }
1816
1817 break;
1818 }
1819 default:
1820 ret = LTTNG_ERR_UND;
1821 goto error_unlock;
1822 }
1823
1824 ret = LTTNG_OK;
1825
1826 error_unlock:
1827 rcu_read_unlock();
1828 error:
1829 return ret;
1830 }
1831
1832 /*
1833 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1834 */
1835 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1836 char *channel_name, const struct lttng_event_context *ctx, int kwpipe)
1837 {
1838 int ret, chan_kern_created = 0, chan_ust_created = 0;
1839 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1840
1841 /*
1842 * Don't try to add a context if the session has been started at
1843 * some point in time before. The tracer does not allow it and would
1844 * result in a corrupted trace.
1845 */
1846 if (session->has_been_started) {
1847 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1848 goto end;
1849 }
1850
1851 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1852 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1853 app_ctx_name = ctx->u.app_ctx.ctx_name;
1854 }
1855
1856 switch (domain) {
1857 case LTTNG_DOMAIN_KERNEL:
1858 assert(session->kernel_session);
1859
1860 if (session->kernel_session->channel_count == 0) {
1861 /* Create default channel */
1862 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1863 if (ret != LTTNG_OK) {
1864 goto error;
1865 }
1866 chan_kern_created = 1;
1867 }
1868 /* Add kernel context to kernel tracer */
1869 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1870 if (ret != LTTNG_OK) {
1871 goto error;
1872 }
1873 break;
1874 case LTTNG_DOMAIN_JUL:
1875 case LTTNG_DOMAIN_LOG4J:
1876 {
1877 /*
1878 * Validate channel name.
1879 * If no channel name is given and the domain is JUL or LOG4J,
1880 * set it to the appropriate domain-specific channel name. If
1881 * a name is provided but does not match the expexted channel
1882 * name, return an error.
1883 */
1884 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1885 strcmp(channel_name,
1886 DEFAULT_JUL_CHANNEL_NAME)) {
1887 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1888 goto error;
1889 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1890 strcmp(channel_name,
1891 DEFAULT_LOG4J_CHANNEL_NAME)) {
1892 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1893 goto error;
1894 }
1895 /* break is _not_ missing here. */
1896 }
1897 case LTTNG_DOMAIN_UST:
1898 {
1899 struct ltt_ust_session *usess = session->ust_session;
1900 unsigned int chan_count;
1901
1902 assert(usess);
1903
1904 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1905 if (chan_count == 0) {
1906 struct lttng_channel *attr;
1907 /* Create default channel */
1908 attr = channel_new_default_attr(domain, usess->buffer_type);
1909 if (attr == NULL) {
1910 ret = LTTNG_ERR_FATAL;
1911 goto error;
1912 }
1913
1914 ret = channel_ust_create(usess, attr, usess->buffer_type);
1915 if (ret != LTTNG_OK) {
1916 free(attr);
1917 goto error;
1918 }
1919 channel_attr_destroy(attr);
1920 chan_ust_created = 1;
1921 }
1922
1923 ret = context_ust_add(usess, domain, ctx, channel_name);
1924 free(app_ctx_provider_name);
1925 free(app_ctx_name);
1926 app_ctx_name = NULL;
1927 app_ctx_provider_name = NULL;
1928 if (ret != LTTNG_OK) {
1929 goto error;
1930 }
1931 break;
1932 }
1933 default:
1934 ret = LTTNG_ERR_UND;
1935 goto error;
1936 }
1937
1938 ret = LTTNG_OK;
1939 goto end;
1940
1941 error:
1942 if (chan_kern_created) {
1943 struct ltt_kernel_channel *kchan =
1944 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1945 session->kernel_session);
1946 /* Created previously, this should NOT fail. */
1947 assert(kchan);
1948 kernel_destroy_channel(kchan);
1949 }
1950
1951 if (chan_ust_created) {
1952 struct ltt_ust_channel *uchan =
1953 trace_ust_find_channel_by_name(
1954 session->ust_session->domain_global.channels,
1955 DEFAULT_CHANNEL_NAME);
1956 /* Created previously, this should NOT fail. */
1957 assert(uchan);
1958 /* Remove from the channel list of the session. */
1959 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1960 uchan);
1961 trace_ust_destroy_channel(uchan);
1962 }
1963 end:
1964 free(app_ctx_provider_name);
1965 free(app_ctx_name);
1966 return ret;
1967 }
1968
1969 static inline bool name_starts_with(const char *name, const char *prefix)
1970 {
1971 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1972
1973 return !strncmp(name, prefix, max_cmp_len);
1974 }
1975
1976 /* Perform userspace-specific event name validation */
1977 static int validate_ust_event_name(const char *name)
1978 {
1979 int ret = 0;
1980
1981 if (!name) {
1982 ret = -1;
1983 goto end;
1984 }
1985
1986 /*
1987 * Check name against all internal UST event component namespaces used
1988 * by the agents.
1989 */
1990 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1991 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1992 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1993 ret = -1;
1994 }
1995
1996 end:
1997 return ret;
1998 }
1999
2000 /*
2001 * Internal version of cmd_enable_event() with a supplemental
2002 * "internal_event" flag which is used to enable internal events which should
2003 * be hidden from clients. Such events are used in the agent implementation to
2004 * enable the events through which all "agent" events are funeled.
2005 */
2006 static int _cmd_enable_event(struct ltt_session *session,
2007 const struct lttng_domain *domain,
2008 char *channel_name, struct lttng_event *event,
2009 char *filter_expression,
2010 struct lttng_filter_bytecode *filter,
2011 struct lttng_event_exclusion *exclusion,
2012 int wpipe, bool internal_event)
2013 {
2014 int ret = 0, channel_created = 0;
2015 struct lttng_channel *attr = NULL;
2016
2017 assert(session);
2018 assert(event);
2019 assert(channel_name);
2020
2021 /* If we have a filter, we must have its filter expression */
2022 assert(!(!!filter_expression ^ !!filter));
2023
2024 /* Normalize event name as a globbing pattern */
2025 strutils_normalize_star_glob_pattern(event->name);
2026
2027 /* Normalize exclusion names as globbing patterns */
2028 if (exclusion) {
2029 size_t i;
2030
2031 for (i = 0; i < exclusion->count; i++) {
2032 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2033
2034 strutils_normalize_star_glob_pattern(name);
2035 }
2036 }
2037
2038 DBG("Enable event command for event \'%s\'", event->name);
2039
2040 rcu_read_lock();
2041
2042 switch (domain->type) {
2043 case LTTNG_DOMAIN_KERNEL:
2044 {
2045 struct ltt_kernel_channel *kchan;
2046
2047 /*
2048 * If a non-default channel has been created in the
2049 * session, explicitely require that -c chan_name needs
2050 * to be provided.
2051 */
2052 if (session->kernel_session->has_non_default_channel
2053 && channel_name[0] == '\0') {
2054 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2055 goto error;
2056 }
2057
2058 kchan = trace_kernel_get_channel_by_name(channel_name,
2059 session->kernel_session);
2060 if (kchan == NULL) {
2061 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2062 LTTNG_BUFFER_GLOBAL);
2063 if (attr == NULL) {
2064 ret = LTTNG_ERR_FATAL;
2065 goto error;
2066 }
2067 if (lttng_strncpy(attr->name, channel_name,
2068 sizeof(attr->name))) {
2069 ret = LTTNG_ERR_INVALID;
2070 goto error;
2071 }
2072
2073 ret = cmd_enable_channel(session, domain, attr, wpipe);
2074 if (ret != LTTNG_OK) {
2075 goto error;
2076 }
2077 channel_created = 1;
2078 }
2079
2080 /* Get the newly created kernel channel pointer */
2081 kchan = trace_kernel_get_channel_by_name(channel_name,
2082 session->kernel_session);
2083 if (kchan == NULL) {
2084 /* This sould not happen... */
2085 ret = LTTNG_ERR_FATAL;
2086 goto error;
2087 }
2088
2089 switch (event->type) {
2090 case LTTNG_EVENT_ALL:
2091 {
2092 char *filter_expression_a = NULL;
2093 struct lttng_filter_bytecode *filter_a = NULL;
2094
2095 /*
2096 * We need to duplicate filter_expression and filter,
2097 * because ownership is passed to first enable
2098 * event.
2099 */
2100 if (filter_expression) {
2101 filter_expression_a = strdup(filter_expression);
2102 if (!filter_expression_a) {
2103 ret = LTTNG_ERR_FATAL;
2104 goto error;
2105 }
2106 }
2107 if (filter) {
2108 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2109 if (!filter_a) {
2110 free(filter_expression_a);
2111 ret = LTTNG_ERR_FATAL;
2112 goto error;
2113 }
2114 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2115 }
2116 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2117 ret = event_kernel_enable_event(kchan, event,
2118 filter_expression, filter);
2119 /* We have passed ownership */
2120 filter_expression = NULL;
2121 filter = NULL;
2122 if (ret != LTTNG_OK) {
2123 if (channel_created) {
2124 /* Let's not leak a useless channel. */
2125 kernel_destroy_channel(kchan);
2126 }
2127 free(filter_expression_a);
2128 free(filter_a);
2129 goto error;
2130 }
2131 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2132 ret = event_kernel_enable_event(kchan, event,
2133 filter_expression_a, filter_a);
2134 /* We have passed ownership */
2135 filter_expression_a = NULL;
2136 filter_a = NULL;
2137 if (ret != LTTNG_OK) {
2138 goto error;
2139 }
2140 break;
2141 }
2142 case LTTNG_EVENT_PROBE:
2143 case LTTNG_EVENT_USERSPACE_PROBE:
2144 case LTTNG_EVENT_FUNCTION:
2145 case LTTNG_EVENT_FUNCTION_ENTRY:
2146 case LTTNG_EVENT_TRACEPOINT:
2147 ret = event_kernel_enable_event(kchan, event,
2148 filter_expression, filter);
2149 /* We have passed ownership */
2150 filter_expression = NULL;
2151 filter = NULL;
2152 if (ret != LTTNG_OK) {
2153 if (channel_created) {
2154 /* Let's not leak a useless channel. */
2155 kernel_destroy_channel(kchan);
2156 }
2157 goto error;
2158 }
2159 break;
2160 case LTTNG_EVENT_SYSCALL:
2161 ret = event_kernel_enable_event(kchan, event,
2162 filter_expression, filter);
2163 /* We have passed ownership */
2164 filter_expression = NULL;
2165 filter = NULL;
2166 if (ret != LTTNG_OK) {
2167 goto error;
2168 }
2169 break;
2170 default:
2171 ret = LTTNG_ERR_UNK;
2172 goto error;
2173 }
2174
2175 kernel_wait_quiescent();
2176 break;
2177 }
2178 case LTTNG_DOMAIN_UST:
2179 {
2180 struct ltt_ust_channel *uchan;
2181 struct ltt_ust_session *usess = session->ust_session;
2182
2183 assert(usess);
2184
2185 /*
2186 * If a non-default channel has been created in the
2187 * session, explicitely require that -c chan_name needs
2188 * to be provided.
2189 */
2190 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2191 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2192 goto error;
2193 }
2194
2195 /* Get channel from global UST domain */
2196 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2197 channel_name);
2198 if (uchan == NULL) {
2199 /* Create default channel */
2200 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2201 usess->buffer_type);
2202 if (attr == NULL) {
2203 ret = LTTNG_ERR_FATAL;
2204 goto error;
2205 }
2206 if (lttng_strncpy(attr->name, channel_name,
2207 sizeof(attr->name))) {
2208 ret = LTTNG_ERR_INVALID;
2209 goto error;
2210 }
2211
2212 ret = cmd_enable_channel(session, domain, attr, wpipe);
2213 if (ret != LTTNG_OK) {
2214 goto error;
2215 }
2216
2217 /* Get the newly created channel reference back */
2218 uchan = trace_ust_find_channel_by_name(
2219 usess->domain_global.channels, channel_name);
2220 assert(uchan);
2221 }
2222
2223 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2224 /*
2225 * Don't allow users to add UST events to channels which
2226 * are assigned to a userspace subdomain (JUL, Log4J,
2227 * Python, etc.).
2228 */
2229 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2230 goto error;
2231 }
2232
2233 if (!internal_event) {
2234 /*
2235 * Ensure the event name is not reserved for internal
2236 * use.
2237 */
2238 ret = validate_ust_event_name(event->name);
2239 if (ret) {
2240 WARN("Userspace event name %s failed validation.",
2241 event->name);
2242 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2243 goto error;
2244 }
2245 }
2246
2247 /* At this point, the session and channel exist on the tracer */
2248 ret = event_ust_enable_tracepoint(usess, uchan, event,
2249 filter_expression, filter, exclusion,
2250 internal_event);
2251 /* We have passed ownership */
2252 filter_expression = NULL;
2253 filter = NULL;
2254 exclusion = NULL;
2255 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2256 goto already_enabled;
2257 } else if (ret != LTTNG_OK) {
2258 goto error;
2259 }
2260 break;
2261 }
2262 case LTTNG_DOMAIN_LOG4J:
2263 case LTTNG_DOMAIN_JUL:
2264 case LTTNG_DOMAIN_PYTHON:
2265 {
2266 const char *default_event_name, *default_chan_name;
2267 struct agent *agt;
2268 struct lttng_event uevent;
2269 struct lttng_domain tmp_dom;
2270 struct ltt_ust_session *usess = session->ust_session;
2271
2272 assert(usess);
2273
2274 if (!agent_tracing_is_enabled()) {
2275 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2276 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2277 goto error;
2278 }
2279
2280 agt = trace_ust_find_agent(usess, domain->type);
2281 if (!agt) {
2282 agt = agent_create(domain->type);
2283 if (!agt) {
2284 ret = LTTNG_ERR_NOMEM;
2285 goto error;
2286 }
2287 agent_add(agt, usess->agents);
2288 }
2289
2290 /* Create the default tracepoint. */
2291 memset(&uevent, 0, sizeof(uevent));
2292 uevent.type = LTTNG_EVENT_TRACEPOINT;
2293 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2294 default_event_name = event_get_default_agent_ust_name(
2295 domain->type);
2296 if (!default_event_name) {
2297 ret = LTTNG_ERR_FATAL;
2298 goto error;
2299 }
2300 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2301 uevent.name[sizeof(uevent.name) - 1] = '\0';
2302
2303 /*
2304 * The domain type is changed because we are about to enable the
2305 * default channel and event for the JUL domain that are hardcoded.
2306 * This happens in the UST domain.
2307 */
2308 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2309 tmp_dom.type = LTTNG_DOMAIN_UST;
2310
2311 switch (domain->type) {
2312 case LTTNG_DOMAIN_LOG4J:
2313 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2314 break;
2315 case LTTNG_DOMAIN_JUL:
2316 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2317 break;
2318 case LTTNG_DOMAIN_PYTHON:
2319 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2320 break;
2321 default:
2322 /* The switch/case we are in makes this impossible */
2323 assert(0);
2324 }
2325
2326 {
2327 char *filter_expression_copy = NULL;
2328 struct lttng_filter_bytecode *filter_copy = NULL;
2329
2330 if (filter) {
2331 const size_t filter_size = sizeof(
2332 struct lttng_filter_bytecode)
2333 + filter->len;
2334
2335 filter_copy = zmalloc(filter_size);
2336 if (!filter_copy) {
2337 ret = LTTNG_ERR_NOMEM;
2338 goto error;
2339 }
2340 memcpy(filter_copy, filter, filter_size);
2341
2342 filter_expression_copy =
2343 strdup(filter_expression);
2344 if (!filter_expression) {
2345 ret = LTTNG_ERR_NOMEM;
2346 }
2347
2348 if (!filter_expression_copy || !filter_copy) {
2349 free(filter_expression_copy);
2350 free(filter_copy);
2351 goto error;
2352 }
2353 }
2354
2355 ret = cmd_enable_event_internal(session, &tmp_dom,
2356 (char *) default_chan_name,
2357 &uevent, filter_expression_copy,
2358 filter_copy, NULL, wpipe);
2359 }
2360
2361 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2362 goto already_enabled;
2363 } else if (ret != LTTNG_OK) {
2364 goto error;
2365 }
2366
2367 /* The wild card * means that everything should be enabled. */
2368 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2369 ret = event_agent_enable_all(usess, agt, event, filter,
2370 filter_expression);
2371 } else {
2372 ret = event_agent_enable(usess, agt, event, filter,
2373 filter_expression);
2374 }
2375 filter = NULL;
2376 filter_expression = NULL;
2377 if (ret != LTTNG_OK) {
2378 goto error;
2379 }
2380
2381 break;
2382 }
2383 default:
2384 ret = LTTNG_ERR_UND;
2385 goto error;
2386 }
2387
2388 ret = LTTNG_OK;
2389
2390 already_enabled:
2391 error:
2392 free(filter_expression);
2393 free(filter);
2394 free(exclusion);
2395 channel_attr_destroy(attr);
2396 rcu_read_unlock();
2397 return ret;
2398 }
2399
2400 /*
2401 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2402 * We own filter, exclusion, and filter_expression.
2403 */
2404 int cmd_enable_event(struct ltt_session *session,
2405 const struct lttng_domain *domain,
2406 char *channel_name, struct lttng_event *event,
2407 char *filter_expression,
2408 struct lttng_filter_bytecode *filter,
2409 struct lttng_event_exclusion *exclusion,
2410 int wpipe)
2411 {
2412 return _cmd_enable_event(session, domain, channel_name, event,
2413 filter_expression, filter, exclusion, wpipe, false);
2414 }
2415
2416 /*
2417 * Enable an event which is internal to LTTng. An internal should
2418 * never be made visible to clients and are immune to checks such as
2419 * reserved names.
2420 */
2421 static int cmd_enable_event_internal(struct ltt_session *session,
2422 const struct lttng_domain *domain,
2423 char *channel_name, struct lttng_event *event,
2424 char *filter_expression,
2425 struct lttng_filter_bytecode *filter,
2426 struct lttng_event_exclusion *exclusion,
2427 int wpipe)
2428 {
2429 return _cmd_enable_event(session, domain, channel_name, event,
2430 filter_expression, filter, exclusion, wpipe, true);
2431 }
2432
2433 /*
2434 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2435 */
2436 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2437 struct lttng_event **events)
2438 {
2439 int ret;
2440 ssize_t nb_events = 0;
2441
2442 switch (domain) {
2443 case LTTNG_DOMAIN_KERNEL:
2444 nb_events = kernel_list_events(events);
2445 if (nb_events < 0) {
2446 ret = LTTNG_ERR_KERN_LIST_FAIL;
2447 goto error;
2448 }
2449 break;
2450 case LTTNG_DOMAIN_UST:
2451 nb_events = ust_app_list_events(events);
2452 if (nb_events < 0) {
2453 ret = LTTNG_ERR_UST_LIST_FAIL;
2454 goto error;
2455 }
2456 break;
2457 case LTTNG_DOMAIN_LOG4J:
2458 case LTTNG_DOMAIN_JUL:
2459 case LTTNG_DOMAIN_PYTHON:
2460 nb_events = agent_list_events(events, domain);
2461 if (nb_events < 0) {
2462 ret = LTTNG_ERR_UST_LIST_FAIL;
2463 goto error;
2464 }
2465 break;
2466 default:
2467 ret = LTTNG_ERR_UND;
2468 goto error;
2469 }
2470
2471 return nb_events;
2472
2473 error:
2474 /* Return negative value to differentiate return code */
2475 return -ret;
2476 }
2477
2478 /*
2479 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2480 */
2481 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2482 struct lttng_event_field **fields)
2483 {
2484 int ret;
2485 ssize_t nb_fields = 0;
2486
2487 switch (domain) {
2488 case LTTNG_DOMAIN_UST:
2489 nb_fields = ust_app_list_event_fields(fields);
2490 if (nb_fields < 0) {
2491 ret = LTTNG_ERR_UST_LIST_FAIL;
2492 goto error;
2493 }
2494 break;
2495 case LTTNG_DOMAIN_KERNEL:
2496 default: /* fall-through */
2497 ret = LTTNG_ERR_UND;
2498 goto error;
2499 }
2500
2501 return nb_fields;
2502
2503 error:
2504 /* Return negative value to differentiate return code */
2505 return -ret;
2506 }
2507
2508 ssize_t cmd_list_syscalls(struct lttng_event **events)
2509 {
2510 return syscall_table_list(events);
2511 }
2512
2513 /*
2514 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2515 *
2516 * Called with session lock held.
2517 */
2518 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2519 enum lttng_domain_type domain, int32_t **pids)
2520 {
2521 int ret;
2522 ssize_t nr_pids = 0;
2523
2524 switch (domain) {
2525 case LTTNG_DOMAIN_KERNEL:
2526 {
2527 struct ltt_kernel_session *ksess;
2528
2529 ksess = session->kernel_session;
2530 nr_pids = kernel_list_tracker_pids(ksess, pids);
2531 if (nr_pids < 0) {
2532 ret = LTTNG_ERR_KERN_LIST_FAIL;
2533 goto error;
2534 }
2535 break;
2536 }
2537 case LTTNG_DOMAIN_UST:
2538 {
2539 struct ltt_ust_session *usess;
2540
2541 usess = session->ust_session;
2542 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2543 if (nr_pids < 0) {
2544 ret = LTTNG_ERR_UST_LIST_FAIL;
2545 goto error;
2546 }
2547 break;
2548 }
2549 case LTTNG_DOMAIN_LOG4J:
2550 case LTTNG_DOMAIN_JUL:
2551 case LTTNG_DOMAIN_PYTHON:
2552 default:
2553 ret = LTTNG_ERR_UND;
2554 goto error;
2555 }
2556
2557 return nr_pids;
2558
2559 error:
2560 /* Return negative value to differentiate return code */
2561 return -ret;
2562 }
2563
2564 /*
2565 * Command LTTNG_START_TRACE processed by the client thread.
2566 *
2567 * Called with session mutex held.
2568 */
2569 int cmd_start_trace(struct ltt_session *session)
2570 {
2571 enum lttng_error_code ret;
2572 unsigned long nb_chan = 0;
2573 struct ltt_kernel_session *ksession;
2574 struct ltt_ust_session *usess;
2575
2576 assert(session);
2577
2578 /* Ease our life a bit ;) */
2579 ksession = session->kernel_session;
2580 usess = session->ust_session;
2581
2582 /* Is the session already started? */
2583 if (session->active) {
2584 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2585 goto error;
2586 }
2587
2588 /*
2589 * Starting a session without channel is useless since after that it's not
2590 * possible to enable channel thus inform the client.
2591 */
2592 if (usess && usess->domain_global.channels) {
2593 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2594 }
2595 if (ksession) {
2596 nb_chan += ksession->channel_count;
2597 }
2598 if (!nb_chan) {
2599 ret = LTTNG_ERR_NO_CHANNEL;
2600 goto error;
2601 }
2602
2603 if (session->output_traces && !session->current_trace_chunk) {
2604 struct lttng_trace_chunk *trace_chunk;
2605
2606 trace_chunk = session_create_new_trace_chunk(
2607 session, NULL, NULL, NULL);
2608 if (!trace_chunk) {
2609 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2610 goto error;
2611 }
2612 assert(!session->current_trace_chunk);
2613 ret = session_set_trace_chunk(session, trace_chunk, NULL);
2614 lttng_trace_chunk_put(trace_chunk);
2615 if (ret) {
2616 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2617 goto error;
2618 }
2619 }
2620
2621 /* Kernel tracing */
2622 if (ksession != NULL) {
2623 DBG("Start kernel tracing session %s", session->name);
2624 ret = start_kernel_session(ksession);
2625 if (ret != LTTNG_OK) {
2626 goto error;
2627 }
2628 }
2629
2630 /* Flag session that trace should start automatically */
2631 if (usess) {
2632 int int_ret = ust_app_start_trace_all(usess);
2633
2634 if (int_ret < 0) {
2635 ret = LTTNG_ERR_UST_START_FAIL;
2636 goto error;
2637 }
2638 }
2639
2640 /* Flag this after a successful start. */
2641 session->has_been_started = 1;
2642 session->active = 1;
2643
2644 /*
2645 * Clear the flag that indicates that a rotation was done while the
2646 * session was stopped.
2647 */
2648 session->rotated_after_last_stop = false;
2649
2650 if (session->rotate_timer_period) {
2651 int int_ret = timer_session_rotation_schedule_timer_start(
2652 session, session->rotate_timer_period);
2653
2654 if (int_ret < 0) {
2655 ERR("Failed to enable rotate timer");
2656 ret = LTTNG_ERR_UNK;
2657 goto error;
2658 }
2659 }
2660
2661 ret = LTTNG_OK;
2662
2663 error:
2664 return ret;
2665 }
2666
2667 /*
2668 * Command LTTNG_STOP_TRACE processed by the client thread.
2669 */
2670 int cmd_stop_trace(struct ltt_session *session)
2671 {
2672 int ret;
2673 struct ltt_kernel_channel *kchan;
2674 struct ltt_kernel_session *ksession;
2675 struct ltt_ust_session *usess;
2676 bool error_occurred = false;
2677
2678 assert(session);
2679
2680 DBG("Begin stop session %s (id %" PRIu64 ")", session->name, session->id);
2681 /* Short cut */
2682 ksession = session->kernel_session;
2683 usess = session->ust_session;
2684
2685 /* Session is not active. Skip everythong and inform the client. */
2686 if (!session->active) {
2687 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2688 goto error;
2689 }
2690
2691 /* Kernel tracer */
2692 if (ksession && ksession->active) {
2693 DBG("Stop kernel tracing");
2694
2695 ret = kernel_stop_session(ksession);
2696 if (ret < 0) {
2697 ret = LTTNG_ERR_KERN_STOP_FAIL;
2698 goto error;
2699 }
2700
2701 kernel_wait_quiescent();
2702
2703 /* Flush metadata after stopping (if exists) */
2704 if (ksession->metadata_stream_fd >= 0) {
2705 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2706 if (ret < 0) {
2707 ERR("Kernel metadata flush failed");
2708 error_occurred = true;
2709 }
2710 }
2711
2712 /* Flush all buffers after stopping */
2713 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2714 ret = kernel_flush_buffer(kchan);
2715 if (ret < 0) {
2716 ERR("Kernel flush buffer error");
2717 error_occurred = true;
2718 }
2719 }
2720
2721 ksession->active = 0;
2722 DBG("Kernel session stopped %s (id %" PRIu64 ")", session->name,
2723 session->id);
2724 }
2725
2726 if (usess && usess->active) {
2727 ret = ust_app_stop_trace_all(usess);
2728 if (ret < 0) {
2729 ret = LTTNG_ERR_UST_STOP_FAIL;
2730 goto error;
2731 }
2732 }
2733
2734 /* Flag inactive after a successful stop. */
2735 session->active = 0;
2736 ret = !error_occurred ? LTTNG_OK : LTTNG_ERR_UNK;
2737
2738 error:
2739 return ret;
2740 }
2741
2742 /*
2743 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2744 */
2745 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2746 struct lttng_uri *uris)
2747 {
2748 int ret, i;
2749 struct ltt_kernel_session *ksess = session->kernel_session;
2750 struct ltt_ust_session *usess = session->ust_session;
2751
2752 assert(session);
2753 assert(uris);
2754 assert(nb_uri > 0);
2755
2756 /* Can't set consumer URI if the session is active. */
2757 if (session->active) {
2758 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2759 goto error;
2760 }
2761
2762 /* Set the "global" consumer URIs */
2763 for (i = 0; i < nb_uri; i++) {
2764 ret = add_uri_to_consumer(session,
2765 session->consumer,
2766 &uris[i], LTTNG_DOMAIN_NONE);
2767 if (ret != LTTNG_OK) {
2768 goto error;
2769 }
2770 }
2771
2772 /* Set UST session URIs */
2773 if (session->ust_session) {
2774 for (i = 0; i < nb_uri; i++) {
2775 ret = add_uri_to_consumer(session,
2776 session->ust_session->consumer,
2777 &uris[i], LTTNG_DOMAIN_UST);
2778 if (ret != LTTNG_OK) {
2779 goto error;
2780 }
2781 }
2782 }
2783
2784 /* Set kernel session URIs */
2785 if (session->kernel_session) {
2786 for (i = 0; i < nb_uri; i++) {
2787 ret = add_uri_to_consumer(session,
2788 session->kernel_session->consumer,
2789 &uris[i], LTTNG_DOMAIN_KERNEL);
2790 if (ret != LTTNG_OK) {
2791 goto error;
2792 }
2793 }
2794 }
2795
2796 /*
2797 * Make sure to set the session in output mode after we set URI since a
2798 * session can be created without URL (thus flagged in no output mode).
2799 */
2800 session->output_traces = 1;
2801 if (ksess) {
2802 ksess->output_traces = 1;
2803 }
2804
2805 if (usess) {
2806 usess->output_traces = 1;
2807 }
2808
2809 /* All good! */
2810 ret = LTTNG_OK;
2811
2812 error:
2813 return ret;
2814 }
2815
2816 static
2817 enum lttng_error_code set_session_output_from_descriptor(
2818 struct ltt_session *session,
2819 const struct lttng_session_descriptor *descriptor)
2820 {
2821 int ret;
2822 enum lttng_error_code ret_code = LTTNG_OK;
2823 enum lttng_session_descriptor_type session_type =
2824 lttng_session_descriptor_get_type(descriptor);
2825 enum lttng_session_descriptor_output_type output_type =
2826 lttng_session_descriptor_get_output_type(descriptor);
2827 struct lttng_uri uris[2] = {};
2828 size_t uri_count = 0;
2829
2830 switch (output_type) {
2831 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
2832 goto end;
2833 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
2834 lttng_session_descriptor_get_local_output_uri(descriptor,
2835 &uris[0]);
2836 uri_count = 1;
2837 break;
2838 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
2839 lttng_session_descriptor_get_network_output_uris(descriptor,
2840 &uris[0], &uris[1]);
2841 uri_count = 2;
2842 break;
2843 default:
2844 ret_code = LTTNG_ERR_INVALID;
2845 goto end;
2846 }
2847
2848 switch (session_type) {
2849 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2850 {
2851 struct snapshot_output *new_output = NULL;
2852
2853 new_output = snapshot_output_alloc();
2854 if (!new_output) {
2855 ret_code = LTTNG_ERR_NOMEM;
2856 goto end;
2857 }
2858
2859 ret = snapshot_output_init_with_uri(session,
2860 DEFAULT_SNAPSHOT_MAX_SIZE,
2861 NULL, uris, uri_count, session->consumer,
2862 new_output, &session->snapshot);
2863 if (ret < 0) {
2864 ret_code = (ret == -ENOMEM) ?
2865 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
2866 snapshot_output_destroy(new_output);
2867 goto end;
2868 }
2869 snapshot_add_output(&session->snapshot, new_output);
2870 break;
2871 }
2872 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
2873 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
2874 {
2875 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
2876 break;
2877 }
2878 default:
2879 ret_code = LTTNG_ERR_INVALID;
2880 goto end;
2881 }
2882 end:
2883 return ret_code;
2884 }
2885
2886 static
2887 enum lttng_error_code cmd_create_session_from_descriptor(
2888 struct lttng_session_descriptor *descriptor,
2889 const lttng_sock_cred *creds,
2890 const char *home_path)
2891 {
2892 int ret;
2893 enum lttng_error_code ret_code;
2894 const char *session_name;
2895 struct ltt_session *new_session = NULL;
2896 enum lttng_session_descriptor_status descriptor_status;
2897 const char *base_path;
2898
2899 session_lock_list();
2900 if (home_path) {
2901 if (*home_path != '/') {
2902 ERR("Home path provided by client is not absolute");
2903 ret_code = LTTNG_ERR_INVALID;
2904 goto end;
2905 }
2906 }
2907
2908 descriptor_status = lttng_session_descriptor_get_session_name(
2909 descriptor, &session_name);
2910 switch (descriptor_status) {
2911 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
2912 break;
2913 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
2914 session_name = NULL;
2915 break;
2916 default:
2917 ret_code = LTTNG_ERR_INVALID;
2918 goto end;
2919 }
2920 ret = lttng_session_descriptor_get_base_path(descriptor, &base_path);
2921 if (ret) {
2922 ret_code = LTTNG_ERR_INVALID;
2923 goto end;
2924 }
2925 ret_code = session_create(session_name, creds->uid, creds->gid,
2926 base_path, &new_session);
2927 if (ret_code != LTTNG_OK) {
2928 goto end;
2929 }
2930
2931 if (!session_name) {
2932 ret = lttng_session_descriptor_set_session_name(descriptor,
2933 new_session->name);
2934 if (ret) {
2935 ret_code = LTTNG_ERR_SESSION_FAIL;
2936 goto end;
2937 }
2938 }
2939
2940 if (!lttng_session_descriptor_is_output_destination_initialized(
2941 descriptor)) {
2942 /*
2943 * Only include the session's creation time in the output
2944 * destination if the name of the session itself was
2945 * not auto-generated.
2946 */
2947 ret_code = lttng_session_descriptor_set_default_output(
2948 descriptor,
2949 session_name ? &new_session->creation_time : NULL,
2950 home_path);
2951 if (ret_code != LTTNG_OK) {
2952 goto end;
2953 }
2954 } else {
2955 new_session->has_user_specified_directory =
2956 lttng_session_descriptor_has_output_directory(
2957 descriptor);
2958 }
2959
2960 switch (lttng_session_descriptor_get_type(descriptor)) {
2961 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2962 new_session->snapshot_mode = 1;
2963 break;
2964 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
2965 new_session->live_timer =
2966 lttng_session_descriptor_live_get_timer_interval(
2967 descriptor);
2968 break;
2969 default:
2970 break;
2971 }
2972
2973 ret_code = set_session_output_from_descriptor(new_session, descriptor);
2974 if (ret_code != LTTNG_OK) {
2975 goto end;
2976 }
2977 new_session->consumer->enabled = 1;
2978 ret_code = LTTNG_OK;
2979 end:
2980 /* Release reference provided by the session_create function. */
2981 session_put(new_session);
2982 if (ret_code != LTTNG_OK && new_session) {
2983 /* Release the global reference on error. */
2984 session_destroy(new_session);
2985 }
2986 session_unlock_list();
2987 return ret_code;
2988 }
2989
2990 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
2991 struct lttng_session_descriptor **return_descriptor)
2992 {
2993 int ret;
2994 size_t payload_size;
2995 struct lttng_dynamic_buffer payload;
2996 struct lttng_buffer_view home_dir_view;
2997 struct lttng_buffer_view session_descriptor_view;
2998 struct lttng_session_descriptor *session_descriptor = NULL;
2999 enum lttng_error_code ret_code;
3000
3001 lttng_dynamic_buffer_init(&payload);
3002 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
3003 LTTNG_PATH_MAX) {
3004 ret_code = LTTNG_ERR_INVALID;
3005 goto error;
3006 }
3007 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
3008 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3009 ret_code = LTTNG_ERR_INVALID;
3010 goto error;
3011 }
3012
3013 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
3014 cmd_ctx->lsm->u.create_session.session_descriptor_size;
3015 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3016 if (ret) {
3017 ret_code = LTTNG_ERR_NOMEM;
3018 goto error;
3019 }
3020
3021 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3022 if (ret <= 0) {
3023 ERR("Reception of session descriptor failed, aborting.");
3024 ret_code = LTTNG_ERR_SESSION_FAIL;
3025 goto error;
3026 }
3027
3028 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3029 &payload,
3030 0,
3031 cmd_ctx->lsm->u.create_session.home_dir_size);
3032 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3033 &payload,
3034 cmd_ctx->lsm->u.create_session.home_dir_size,
3035 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3036
3037 ret = lttng_session_descriptor_create_from_buffer(
3038 &session_descriptor_view, &session_descriptor);
3039 if (ret < 0) {
3040 ERR("Failed to create session descriptor from payload of \"create session\" command");
3041 ret_code = LTTNG_ERR_INVALID;
3042 goto error;
3043 }
3044
3045 /*
3046 * Sets the descriptor's auto-generated properties (name, output) if
3047 * needed.
3048 */
3049 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3050 &cmd_ctx->creds,
3051 home_dir_view.size ? home_dir_view.data : NULL);
3052 if (ret_code != LTTNG_OK) {
3053 goto error;
3054 }
3055
3056 ret_code = LTTNG_OK;
3057 *return_descriptor = session_descriptor;
3058 session_descriptor = NULL;
3059 error:
3060 lttng_dynamic_buffer_reset(&payload);
3061 lttng_session_descriptor_destroy(session_descriptor);
3062 return ret_code;
3063 }
3064
3065 static
3066 void cmd_destroy_session_reply(const struct ltt_session *session,
3067 void *_reply_context)
3068 {
3069 int ret;
3070 ssize_t comm_ret;
3071 const struct cmd_destroy_session_reply_context *reply_context =
3072 _reply_context;
3073 struct lttng_dynamic_buffer payload;
3074 struct lttcomm_session_destroy_command_header cmd_header;
3075 struct lttng_trace_archive_location *location = NULL;
3076 struct lttcomm_lttng_msg llm = {
3077 .cmd_type = LTTNG_DESTROY_SESSION,
3078 .ret_code = reply_context->destruction_status,
3079 .pid = UINT32_MAX,
3080 .cmd_header_size =
3081 sizeof(struct lttcomm_session_destroy_command_header),
3082 .data_size = 0,
3083 };
3084 size_t payload_size_before_location;
3085
3086 lttng_dynamic_buffer_init(&payload);
3087
3088 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3089 if (ret) {
3090 ERR("Failed to append session destruction message");
3091 goto error;
3092 }
3093
3094 cmd_header.rotation_state =
3095 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3096 session->rotation_state :
3097 LTTNG_ROTATION_STATE_NO_ROTATION);
3098 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3099 sizeof(cmd_header));
3100 if (ret) {
3101 ERR("Failed to append session destruction command header");
3102 goto error;
3103 }
3104
3105 if (!reply_context->implicit_rotation_on_destroy) {
3106 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3107 session->name);
3108 goto send_reply;
3109 }
3110 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3111 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3112 session->name);
3113 goto send_reply;
3114 }
3115
3116 location = session_get_trace_archive_location(session);
3117 if (!location) {
3118 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3119 session->name);
3120 goto error;
3121 }
3122
3123 payload_size_before_location = payload.size;
3124 comm_ret = lttng_trace_archive_location_serialize(location,
3125 &payload);
3126 if (comm_ret < 0) {
3127 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3128 session->name);
3129 goto error;
3130 }
3131 /* Update the message to indicate the location's length. */
3132 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3133 payload.size - payload_size_before_location;
3134 send_reply:
3135 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3136 payload.data, payload.size);
3137 if (comm_ret != (ssize_t) payload.size) {
3138 ERR("Failed to send result of the destruction of session \"%s\" to client",
3139 session->name);
3140 }
3141 error:
3142 ret = close(reply_context->reply_sock_fd);
3143 if (ret) {
3144 PERROR("Failed to close client socket in deferred session destroy reply");
3145 }
3146 lttng_dynamic_buffer_reset(&payload);
3147 free(_reply_context);
3148 }
3149
3150 /*
3151 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3152 *
3153 * Called with session lock held.
3154 */
3155 int cmd_destroy_session(struct ltt_session *session,
3156 struct notification_thread_handle *notification_thread_handle,
3157 int *sock_fd)
3158 {
3159 int ret;
3160 enum lttng_error_code destruction_last_error = LTTNG_OK;
3161 struct cmd_destroy_session_reply_context *reply_context = NULL;
3162
3163 if (sock_fd) {
3164 reply_context = zmalloc(sizeof(*reply_context));
3165 if (!reply_context) {
3166 ret = LTTNG_ERR_NOMEM;
3167 goto end;
3168 }
3169 reply_context->reply_sock_fd = *sock_fd;
3170 }
3171
3172 /* Safety net */
3173 assert(session);
3174
3175 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3176 session->id);
3177 if (session->active) {
3178 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3179 session->name);
3180 ret = cmd_stop_trace(session);
3181 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3182 /* Carry on with the destruction of the session. */
3183 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3184 session->name, lttng_strerror(-ret));
3185 destruction_last_error = ret;
3186 }
3187 }
3188
3189 if (session->rotation_schedule_timer_enabled) {
3190 if (timer_session_rotation_schedule_timer_stop(
3191 session)) {
3192 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3193 session->name);
3194 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3195 }
3196 }
3197
3198 if (session->rotate_size) {
3199 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3200 session->rotate_size = 0;
3201 }
3202
3203 if (session->most_recent_chunk_id.is_set &&
3204 session->most_recent_chunk_id.value != 0 &&
3205 session->current_trace_chunk && session->output_traces) {
3206 /*
3207 * Perform a last rotation on destruction if rotations have
3208 * occurred during the session's lifetime.
3209 */
3210 ret = cmd_rotate_session(session, NULL, false);
3211 if (ret != LTTNG_OK) {
3212 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3213 session->name, lttng_strerror(-ret));
3214 destruction_last_error = -ret;
3215 }
3216 if (reply_context) {
3217 reply_context->implicit_rotation_on_destroy = true;
3218 }
3219 } else if (session->has_been_started && session->current_trace_chunk) {
3220 /*
3221 * The user has not triggered a session rotation. However, to
3222 * ensure all data has been consumed, the session is rotated
3223 * to a 'null' trace chunk before it is destroyed.
3224 *
3225 * This is a "quiet" rotation meaning that no notification is
3226 * emitted and no renaming of the current trace chunk takes
3227 * place.
3228 */
3229 ret = cmd_rotate_session(session, NULL, true);
3230 if (ret != LTTNG_OK) {
3231 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3232 session->name, lttng_strerror(-ret));
3233 destruction_last_error = -ret;
3234 }
3235 }
3236
3237 if (session->shm_path[0]) {
3238 /*
3239 * When a session is created with an explicit shm_path,
3240 * the consumer daemon will create its shared memory files
3241 * at that location and will *not* unlink them. This is normal
3242 * as the intention of that feature is to make it possible
3243 * to retrieve the content of those files should a crash occur.
3244 *
3245 * To ensure the content of those files can be used, the
3246 * sessiond daemon will replicate the content of the metadata
3247 * cache in a metadata file.
3248 *
3249 * On clean-up, it is expected that the consumer daemon will
3250 * unlink the shared memory files and that the session daemon
3251 * will unlink the metadata file. Then, the session's directory
3252 * in the shm path can be removed.
3253 *
3254 * Unfortunately, a flaw in the design of the sessiond's and
3255 * consumerd's tear down of channels makes it impossible to
3256 * determine when the sessiond _and_ the consumerd have both
3257 * destroyed their representation of a channel. For one, the
3258 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3259 * callbacks in both daemons.
3260 *
3261 * However, it is also impossible for the sessiond to know when
3262 * the consumer daemon is done destroying its channel(s) since
3263 * it occurs as a reaction to the closing of the channel's file
3264 * descriptor. There is no resulting communication initiated
3265 * from the consumerd to the sessiond to confirm that the
3266 * operation is completed (and was successful).
3267 *
3268 * Until this is all fixed, the session daemon checks for the
3269 * removal of the session's shm path which makes it possible
3270 * to safely advertise a session as having been destroyed.
3271 *
3272 * Prior to this fix, it was not possible to reliably save
3273 * a session making use of the --shm-path option, destroy it,
3274 * and load it again. This is because the creation of the
3275 * session would fail upon seeing the session's shm path
3276 * already in existence.
3277 *
3278 * Note that none of the error paths in the check for the
3279 * directory's existence return an error. This is normal
3280 * as there isn't much that can be done. The session will
3281 * be destroyed properly, except that we can't offer the
3282 * guarantee that the same session can be re-created.
3283 */
3284 current_completion_handler = &destroy_completion_handler.handler;
3285 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3286 session->shm_path,
3287 sizeof(destroy_completion_handler.shm_path));
3288 assert(!ret);
3289 }
3290
3291 /*
3292 * The session is destroyed. However, note that the command context
3293 * still holds a reference to the session, thus delaying its destruction
3294 * _at least_ up to the point when that reference is released.
3295 */
3296 session_destroy(session);
3297 if (reply_context) {
3298 reply_context->destruction_status = destruction_last_error;
3299 ret = session_add_destroy_notifier(session,
3300 cmd_destroy_session_reply,
3301 (void *) reply_context);
3302 if (ret) {
3303 ret = LTTNG_ERR_FATAL;
3304 goto end;
3305 } else {
3306 *sock_fd = -1;
3307 }
3308 }
3309 ret = LTTNG_OK;
3310 end:
3311 return ret;
3312 }
3313
3314 /*
3315 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3316 */
3317 int cmd_register_consumer(struct ltt_session *session,
3318 enum lttng_domain_type domain, const char *sock_path,
3319 struct consumer_data *cdata)
3320 {
3321 int ret, sock;
3322 struct consumer_socket *socket = NULL;
3323
3324 assert(session);
3325 assert(cdata);
3326 assert(sock_path);
3327
3328 switch (domain) {
3329 case LTTNG_DOMAIN_KERNEL:
3330 {
3331 struct ltt_kernel_session *ksess = session->kernel_session;
3332
3333 assert(ksess);
3334
3335 /* Can't register a consumer if there is already one */
3336 if (ksess->consumer_fds_sent != 0) {
3337 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3338 goto error;
3339 }
3340
3341 sock = lttcomm_connect_unix_sock(sock_path);
3342 if (sock < 0) {
3343 ret = LTTNG_ERR_CONNECT_FAIL;
3344 goto error;
3345 }
3346 cdata->cmd_sock = sock;
3347
3348 socket = consumer_allocate_socket(&cdata->cmd_sock);
3349 if (socket == NULL) {
3350 ret = close(sock);
3351 if (ret < 0) {
3352 PERROR("close register consumer");
3353 }
3354 cdata->cmd_sock = -1;
3355 ret = LTTNG_ERR_FATAL;
3356 goto error;
3357 }
3358
3359 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3360 if (socket->lock == NULL) {
3361 PERROR("zmalloc pthread mutex");
3362 ret = LTTNG_ERR_FATAL;
3363 goto error;
3364 }
3365 pthread_mutex_init(socket->lock, NULL);
3366 socket->registered = 1;
3367
3368 rcu_read_lock();
3369 consumer_add_socket(socket, ksess->consumer);
3370 rcu_read_unlock();
3371
3372 pthread_mutex_lock(&cdata->pid_mutex);
3373 cdata->pid = -1;
3374 pthread_mutex_unlock(&cdata->pid_mutex);
3375
3376 break;
3377 }
3378 default:
3379 /* TODO: Userspace tracing */
3380 ret = LTTNG_ERR_UND;
3381 goto error;
3382 }
3383
3384 return LTTNG_OK;
3385
3386 error:
3387 if (socket) {
3388 consumer_destroy_socket(socket);
3389 }
3390 return ret;
3391 }
3392
3393 /*
3394 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3395 */
3396 ssize_t cmd_list_domains(struct ltt_session *session,
3397 struct lttng_domain **domains)
3398 {
3399 int ret, index = 0;
3400 ssize_t nb_dom = 0;
3401 struct agent *agt;
3402 struct lttng_ht_iter iter;
3403
3404 if (session->kernel_session != NULL) {
3405 DBG3("Listing domains found kernel domain");
3406 nb_dom++;
3407 }
3408
3409 if (session->ust_session != NULL) {
3410 DBG3("Listing domains found UST global domain");
3411 nb_dom++;
3412
3413 rcu_read_lock();
3414 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3415 agt, node.node) {
3416 if (agt->being_used) {
3417 nb_dom++;
3418 }
3419 }
3420 rcu_read_unlock();
3421 }
3422
3423 if (!nb_dom) {
3424 goto end;
3425 }
3426
3427 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3428 if (*domains == NULL) {
3429 ret = LTTNG_ERR_FATAL;
3430 goto error;
3431 }
3432
3433 if (session->kernel_session != NULL) {
3434 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3435
3436 /* Kernel session buffer type is always GLOBAL */
3437 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3438
3439 index++;
3440 }
3441
3442 if (session->ust_session != NULL) {
3443 (*domains)[index].type = LTTNG_DOMAIN_UST;
3444 (*domains)[index].buf_type = session->ust_session->buffer_type;
3445 index++;
3446
3447 rcu_read_lock();
3448 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3449 agt, node.node) {
3450 if (agt->being_used) {
3451 (*domains)[index].type = agt->domain;
3452 (*domains)[index].buf_type = session->ust_session->buffer_type;
3453 index++;
3454 }
3455 }
3456 rcu_read_unlock();
3457 }
3458 end:
3459 return nb_dom;
3460
3461 error:
3462 /* Return negative value to differentiate return code */
3463 return -ret;
3464 }
3465
3466
3467 /*
3468 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3469 */
3470 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3471 struct ltt_session *session, struct lttng_channel **channels)
3472 {
3473 ssize_t nb_chan = 0, payload_size = 0, ret;
3474
3475 switch (domain) {
3476 case LTTNG_DOMAIN_KERNEL:
3477 if (session->kernel_session != NULL) {
3478 nb_chan = session->kernel_session->channel_count;
3479 }
3480 DBG3("Number of kernel channels %zd", nb_chan);
3481 if (nb_chan <= 0) {
3482 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3483 goto end;
3484 }
3485 break;
3486 case LTTNG_DOMAIN_UST:
3487 if (session->ust_session != NULL) {
3488 rcu_read_lock();
3489 nb_chan = lttng_ht_get_count(
3490 session->ust_session->domain_global.channels);
3491 rcu_read_unlock();
3492 }
3493 DBG3("Number of UST global channels %zd", nb_chan);
3494 if (nb_chan < 0) {
3495 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3496 goto end;
3497 }
3498 break;
3499 default:
3500 ret = -LTTNG_ERR_UND;
3501 goto end;
3502 }
3503
3504 if (nb_chan > 0) {
3505 const size_t channel_size = sizeof(struct lttng_channel) +
3506 sizeof(struct lttng_channel_extended);
3507 struct lttng_channel_extended *channel_exts;
3508
3509 payload_size = nb_chan * channel_size;
3510 *channels = zmalloc(payload_size);
3511 if (*channels == NULL) {
3512 ret = -LTTNG_ERR_FATAL;
3513 goto end;
3514 }
3515
3516 channel_exts = ((void *) *channels) +
3517 (nb_chan * sizeof(struct lttng_channel));
3518 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3519 if (ret != LTTNG_OK) {
3520 free(*channels);
3521 *channels = NULL;
3522 goto end;
3523 }
3524 } else {
3525 *channels = NULL;
3526 }
3527
3528 ret = payload_size;
3529 end:
3530 return ret;
3531 }
3532
3533 /*
3534 * Command LTTNG_LIST_EVENTS processed by the client thread.
3535 */
3536 ssize_t cmd_list_events(enum lttng_domain_type domain,
3537 struct ltt_session *session, char *channel_name,
3538 struct lttng_event **events, size_t *total_size)
3539 {
3540 int ret = 0;
3541 ssize_t nb_event = 0;
3542
3543 switch (domain) {
3544 case LTTNG_DOMAIN_KERNEL:
3545 if (session->kernel_session != NULL) {
3546 nb_event = list_lttng_kernel_events(channel_name,
3547 session->kernel_session, events,
3548 total_size);
3549 }
3550 break;
3551 case LTTNG_DOMAIN_UST:
3552 {
3553 if (session->ust_session != NULL) {
3554 nb_event = list_lttng_ust_global_events(channel_name,
3555 &session->ust_session->domain_global, events,
3556 total_size);
3557 }
3558 break;
3559 }
3560 case LTTNG_DOMAIN_LOG4J:
3561 case LTTNG_DOMAIN_JUL:
3562 case LTTNG_DOMAIN_PYTHON:
3563 if (session->ust_session) {
3564 struct lttng_ht_iter iter;
3565 struct agent *agt;
3566
3567 rcu_read_lock();
3568 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3569 &iter.iter, agt, node.node) {
3570 if (agt->domain == domain) {
3571 nb_event = list_lttng_agent_events(
3572 agt, events,
3573 total_size);
3574 break;
3575 }
3576 }
3577 rcu_read_unlock();
3578 }
3579 break;
3580 default:
3581 ret = LTTNG_ERR_UND;
3582 goto error;
3583 }
3584
3585 return nb_event;
3586
3587 error:
3588 /* Return negative value to differentiate return code */
3589 return -ret;
3590 }
3591
3592 /*
3593 * Using the session list, filled a lttng_session array to send back to the
3594 * client for session listing.
3595 *
3596 * The session list lock MUST be acquired before calling this function. Use
3597 * session_lock_list() and session_unlock_list().
3598 */
3599 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3600 size_t session_count, uid_t uid, gid_t gid)
3601 {
3602 int ret;
3603 unsigned int i = 0;
3604 struct ltt_session *session;
3605 struct ltt_session_list *list = session_get_list();
3606 struct lttng_session_extended *extended =
3607 (typeof(extended)) (&sessions[session_count]);
3608
3609 DBG("Getting all available session for UID %d GID %d",
3610 uid, gid);
3611 /*
3612 * Iterate over session list and append data after the control struct in
3613 * the buffer.
3614 */
3615 cds_list_for_each_entry(session, &list->head, list) {
3616 if (!session_get(session)) {
3617 continue;
3618 }
3619 /*
3620 * Only list the sessions the user can control.
3621 */
3622 if (!session_access_ok(session, uid, gid) ||
3623 session->destroyed) {
3624 session_put(session);
3625 continue;
3626 }
3627
3628 struct ltt_kernel_session *ksess = session->kernel_session;
3629 struct ltt_ust_session *usess = session->ust_session;
3630
3631 if (session->consumer->type == CONSUMER_DST_NET ||
3632 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3633 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3634 ret = build_network_session_path(sessions[i].path,
3635 sizeof(sessions[i].path), session);
3636 } else {
3637 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3638 session->consumer->dst.session_root_path);
3639 }
3640 if (ret < 0) {
3641 PERROR("snprintf session path");
3642 session_put(session);
3643 continue;
3644 }
3645
3646 strncpy(sessions[i].name, session->name, NAME_MAX);
3647 sessions[i].name[NAME_MAX - 1] = '\0';
3648 sessions[i].enabled = session->active;
3649 sessions[i].snapshot_mode = session->snapshot_mode;
3650 sessions[i].live_timer_interval = session->live_timer;
3651 extended[i].creation_time.value = (uint64_t) session->creation_time;
3652 extended[i].creation_time.is_set = 1;
3653 i++;
3654 session_put(session);
3655 }
3656 }
3657
3658 /*
3659 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3660 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3661 */
3662 int cmd_data_pending(struct ltt_session *session)
3663 {
3664 int ret;
3665 struct ltt_kernel_session *ksess = session->kernel_session;
3666 struct ltt_ust_session *usess = session->ust_session;
3667
3668 assert(session);
3669
3670 DBG("Data pending for session %s", session->name);
3671
3672 /* Session MUST be stopped to ask for data availability. */
3673 if (session->active) {
3674 ret = LTTNG_ERR_SESSION_STARTED;
3675 goto error;
3676 } else {
3677 /*
3678 * If stopped, just make sure we've started before else the above call
3679 * will always send that there is data pending.
3680 *
3681 * The consumer assumes that when the data pending command is received,
3682 * the trace has been started before or else no output data is written
3683 * by the streams which is a condition for data pending. So, this is
3684 * *VERY* important that we don't ask the consumer before a start
3685 * trace.
3686 */
3687 if (!session->has_been_started) {
3688 ret = 0;
3689 goto error;
3690 }
3691 }
3692
3693 /* A rotation is still pending, we have to wait. */
3694 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3695 DBG("Rotate still pending for session %s", session->name);
3696 ret = 1;
3697 goto error;
3698 }
3699
3700 if (ksess && ksess->consumer) {
3701 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3702 if (ret == 1) {
3703 /* Data is still being extracted for the kernel. */
3704 goto error;
3705 }
3706 }
3707
3708 if (usess && usess->consumer) {
3709 ret = consumer_is_data_pending(usess->id, usess->consumer);
3710 if (ret == 1) {
3711 /* Data is still being extracted for the kernel. */
3712 goto error;
3713 }
3714 }
3715
3716 /* Data is ready to be read by a viewer */
3717 ret = 0;
3718
3719 error:
3720 return ret;
3721 }
3722
3723 /*
3724 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3725 *
3726 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3727 */
3728 int cmd_snapshot_add_output(struct ltt_session *session,
3729 const struct lttng_snapshot_output *output, uint32_t *id)
3730 {
3731 int ret;
3732 struct snapshot_output *new_output;
3733
3734 assert(session);
3735 assert(output);
3736
3737 DBG("Cmd snapshot add output for session %s", session->name);
3738
3739 /*
3740 * Can't create an output if the session is not set in no-output mode.
3741 */
3742 if (session->output_traces) {
3743 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3744 goto error;
3745 }
3746
3747 if (session->has_non_mmap_channel) {
3748 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3749 goto error;
3750 }
3751
3752 /* Only one output is allowed until we have the "tee" feature. */
3753 if (session->snapshot.nb_output == 1) {
3754 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3755 goto error;
3756 }
3757
3758 new_output = snapshot_output_alloc();
3759 if (!new_output) {
3760 ret = LTTNG_ERR_NOMEM;
3761 goto error;
3762 }
3763
3764 ret = snapshot_output_init(session, output->max_size, output->name,
3765 output->ctrl_url, output->data_url, session->consumer, new_output,
3766 &session->snapshot);
3767 if (ret < 0) {
3768 if (ret == -ENOMEM) {
3769 ret = LTTNG_ERR_NOMEM;
3770 } else {
3771 ret = LTTNG_ERR_INVALID;
3772 }
3773 goto free_error;
3774 }
3775
3776 rcu_read_lock();
3777 snapshot_add_output(&session->snapshot, new_output);
3778 if (id) {
3779 *id = new_output->id;
3780 }
3781 rcu_read_unlock();
3782
3783 return LTTNG_OK;
3784
3785 free_error:
3786 snapshot_output_destroy(new_output);
3787 error:
3788 return ret;
3789 }
3790
3791 /*
3792 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3793 *
3794 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3795 */
3796 int cmd_snapshot_del_output(struct ltt_session *session,
3797 const struct lttng_snapshot_output *output)
3798 {
3799 int ret;
3800 struct snapshot_output *sout = NULL;
3801
3802 assert(session);
3803 assert(output);
3804
3805 rcu_read_lock();
3806
3807 /*
3808 * Permission denied to create an output if the session is not
3809 * set in no output mode.
3810 */
3811 if (session->output_traces) {
3812 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3813 goto error;
3814 }
3815
3816 if (output->id) {
3817 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3818 session->name);
3819 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3820 } else if (*output->name != '\0') {
3821 DBG("Cmd snapshot del output name %s for session %s", output->name,
3822 session->name);
3823 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3824 }
3825 if (!sout) {
3826 ret = LTTNG_ERR_INVALID;
3827 goto error;
3828 }
3829
3830 snapshot_delete_output(&session->snapshot, sout);
3831 snapshot_output_destroy(sout);
3832 ret = LTTNG_OK;
3833
3834 error:
3835 rcu_read_unlock();
3836 return ret;
3837 }
3838
3839 /*
3840 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3841 *
3842 * If no output is available, outputs is untouched and 0 is returned.
3843 *
3844 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3845 */
3846 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3847 struct lttng_snapshot_output **outputs)
3848 {
3849 int ret, idx = 0;
3850 struct lttng_snapshot_output *list = NULL;
3851 struct lttng_ht_iter iter;
3852 struct snapshot_output *output;
3853
3854 assert(session);
3855 assert(outputs);
3856
3857 DBG("Cmd snapshot list outputs for session %s", session->name);
3858
3859 /*
3860 * Permission denied to create an output if the session is not
3861 * set in no output mode.
3862 */
3863 if (session->output_traces) {
3864 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3865 goto end;
3866 }
3867
3868 if (session->snapshot.nb_output == 0) {
3869 ret = 0;
3870 goto end;
3871 }
3872
3873 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3874 if (!list) {
3875 ret = -LTTNG_ERR_NOMEM;
3876 goto end;
3877 }
3878
3879 /* Copy list from session to the new list object. */
3880 rcu_read_lock();
3881 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
3882 output, node.node) {
3883 assert(output->consumer);
3884 list[idx].id = output->id;
3885 list[idx].max_size = output->max_size;
3886 if (lttng_strncpy(list[idx].name, output->name,
3887 sizeof(list[idx].name))) {
3888 ret = -LTTNG_ERR_INVALID;
3889 goto error;
3890 }
3891 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3892 if (lttng_strncpy(list[idx].ctrl_url,
3893 output->consumer->dst.session_root_path,
3894 sizeof(list[idx].ctrl_url))) {
3895 ret = -LTTNG_ERR_INVALID;
3896 goto error;
3897 }
3898 } else {
3899 /* Control URI. */
3900 ret = uri_to_str_url(&output->consumer->dst.net.control,
3901 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3902 if (ret < 0) {
3903 ret = -LTTNG_ERR_NOMEM;
3904 goto error;
3905 }
3906
3907 /* Data URI. */
3908 ret = uri_to_str_url(&output->consumer->dst.net.data,
3909 list[idx].data_url, sizeof(list[idx].data_url));
3910 if (ret < 0) {
3911 ret = -LTTNG_ERR_NOMEM;
3912 goto error;
3913 }
3914 }
3915 idx++;
3916 }
3917
3918 *outputs = list;
3919 list = NULL;
3920 ret = session->snapshot.nb_output;
3921 error:
3922 rcu_read_unlock();
3923 free(list);
3924 end:
3925 return ret;
3926 }
3927
3928 /*
3929 * Check if we can regenerate the metadata for this session.
3930 * Only kernel, UST per-uid and non-live sessions are supported.
3931 *
3932 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
3933 */
3934 static
3935 int check_regenerate_metadata_support(struct ltt_session *session)
3936 {
3937 int ret;
3938
3939 assert(session);
3940
3941 if (session->live_timer != 0) {
3942 ret = LTTNG_ERR_LIVE_SESSION;
3943 goto end;
3944 }
3945 if (!session->active) {
3946 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3947 goto end;
3948 }
3949 if (session->ust_session) {
3950 switch (session->ust_session->buffer_type) {
3951 case LTTNG_BUFFER_PER_UID:
3952 break;
3953 case LTTNG_BUFFER_PER_PID:
3954 ret = LTTNG_ERR_PER_PID_SESSION;
3955 goto end;
3956 default:
3957 assert(0);
3958 ret = LTTNG_ERR_UNK;
3959 goto end;
3960 }
3961 }
3962 if (session->consumer->type == CONSUMER_DST_NET &&
3963 session->consumer->relay_minor_version < 8) {
3964 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
3965 goto end;
3966 }
3967 ret = 0;
3968
3969 end:
3970 return ret;
3971 }
3972
3973 static
3974 int clear_metadata_file(int fd)
3975 {
3976 int ret;
3977 off_t lseek_ret;
3978
3979 lseek_ret = lseek(fd, 0, SEEK_SET);
3980 if (lseek_ret < 0) {
3981 PERROR("lseek");
3982 ret = -1;
3983 goto end;
3984 }
3985
3986 ret = ftruncate(fd, 0);
3987 if (ret < 0) {
3988 PERROR("ftruncate");
3989 goto end;
3990 }
3991
3992 end:
3993 return ret;
3994 }
3995
3996 static
3997 int ust_regenerate_metadata(struct ltt_ust_session *usess)
3998 {
3999 int ret = 0;
4000 struct buffer_reg_uid *uid_reg = NULL;
4001 struct buffer_reg_session *session_reg = NULL;
4002
4003 rcu_read_lock();
4004 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4005 struct ust_registry_session *registry;
4006 struct ust_registry_channel *chan;
4007 struct lttng_ht_iter iter_chan;
4008
4009 session_reg = uid_reg->registry;
4010 registry = session_reg->reg.ust;
4011
4012 pthread_mutex_lock(&registry->lock);
4013 registry->metadata_len_sent = 0;
4014 memset(registry->metadata, 0, registry->metadata_alloc_len);
4015 registry->metadata_len = 0;
4016 registry->metadata_version++;
4017 if (registry->metadata_fd > 0) {
4018 /* Clear the metadata file's content. */
4019 ret = clear_metadata_file(registry->metadata_fd);
4020 if (ret) {
4021 pthread_mutex_unlock(&registry->lock);
4022 goto end;
4023 }
4024 }
4025
4026 ret = ust_metadata_session_statedump(registry, NULL,
4027 registry->major, registry->minor);
4028 if (ret) {
4029 pthread_mutex_unlock(&registry->lock);
4030 ERR("Failed to generate session metadata (err = %d)",
4031 ret);
4032 goto end;
4033 }
4034 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4035 chan, node.node) {
4036 struct ust_registry_event *event;
4037 struct lttng_ht_iter iter_event;
4038
4039 ret = ust_metadata_channel_statedump(registry, chan);
4040 if (ret) {
4041 pthread_mutex_unlock(&registry->lock);
4042 ERR("Failed to generate channel metadata "
4043 "(err = %d)", ret);
4044 goto end;
4045 }
4046 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4047 event, node.node) {
4048 ret = ust_metadata_event_statedump(registry,
4049 chan, event);
4050 if (ret) {
4051 pthread_mutex_unlock(&registry->lock);
4052 ERR("Failed to generate event metadata "
4053 "(err = %d)", ret);
4054 goto end;
4055 }
4056 }
4057 }
4058 pthread_mutex_unlock(&registry->lock);
4059 }
4060
4061 end:
4062 rcu_read_unlock();
4063 return ret;
4064 }
4065
4066 /*
4067 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4068 *
4069 * Ask the consumer to truncate the existing metadata file(s) and
4070 * then regenerate the metadata. Live and per-pid sessions are not
4071 * supported and return an error.
4072 *
4073 * Return 0 on success or else a LTTNG_ERR code.
4074 */
4075 int cmd_regenerate_metadata(struct ltt_session *session)
4076 {
4077 int ret;
4078
4079 assert(session);
4080
4081 ret = check_regenerate_metadata_support(session);
4082 if (ret) {
4083 goto end;
4084 }
4085
4086 if (session->kernel_session) {
4087 ret = kernctl_session_regenerate_metadata(
4088 session->kernel_session->fd);
4089 if (ret < 0) {
4090 ERR("Failed to regenerate the kernel metadata");
4091 goto end;
4092 }
4093 }
4094
4095 if (session->ust_session) {
4096 ret = ust_regenerate_metadata(session->ust_session);
4097 if (ret < 0) {
4098 ERR("Failed to regenerate the UST metadata");
4099 goto end;
4100 }
4101 }
4102 DBG("Cmd metadata regenerate for session %s", session->name);
4103 ret = LTTNG_OK;
4104
4105 end:
4106 return ret;
4107 }
4108
4109 /*
4110 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4111 *
4112 * Ask the tracer to regenerate a new statedump.
4113 *
4114 * Return 0 on success or else a LTTNG_ERR code.
4115 */
4116 int cmd_regenerate_statedump(struct ltt_session *session)
4117 {
4118 int ret;
4119
4120 assert(session);
4121
4122 if (!session->active) {
4123 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4124 goto end;
4125 }
4126
4127 if (session->kernel_session) {
4128 ret = kernctl_session_regenerate_statedump(
4129 session->kernel_session->fd);
4130 /*
4131 * Currently, the statedump in kernel can only fail if out
4132 * of memory.
4133 */
4134 if (ret < 0) {
4135 if (ret == -ENOMEM) {
4136 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4137 } else {
4138 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4139 }
4140 ERR("Failed to regenerate the kernel statedump");
4141 goto end;
4142 }
4143 }
4144
4145 if (session->ust_session) {
4146 ret = ust_app_regenerate_statedump_all(session->ust_session);
4147 /*
4148 * Currently, the statedump in UST always returns 0.
4149 */
4150 if (ret < 0) {
4151 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4152 ERR("Failed to regenerate the UST statedump");
4153 goto end;
4154 }
4155 }
4156 DBG("Cmd regenerate statedump for session %s", session->name);
4157 ret = LTTNG_OK;
4158
4159 end:
4160 return ret;
4161 }
4162
4163 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4164 struct notification_thread_handle *notification_thread)
4165 {
4166 int ret;
4167 size_t trigger_len;
4168 ssize_t sock_recv_len;
4169 struct lttng_trigger *trigger = NULL;
4170 struct lttng_buffer_view view;
4171 struct lttng_dynamic_buffer trigger_buffer;
4172
4173 lttng_dynamic_buffer_init(&trigger_buffer);
4174 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4175 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4176 if (ret) {
4177 ret = LTTNG_ERR_NOMEM;
4178 goto end;
4179 }
4180
4181 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4182 trigger_len);
4183 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4184 ERR("Failed to receive \"register trigger\" command payload");
4185 /* TODO: should this be a new error enum ? */
4186 ret = LTTNG_ERR_INVALID_TRIGGER;
4187 goto end;
4188 }
4189
4190 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4191 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4192 trigger_len) {
4193 ERR("Invalid trigger payload received in \"register trigger\" command");
4194 ret = LTTNG_ERR_INVALID_TRIGGER;
4195 goto end;
4196 }
4197
4198 ret = notification_thread_command_register_trigger(notification_thread,
4199 trigger);
4200 /* Ownership of trigger was transferred. */
4201 trigger = NULL;
4202 end:
4203 lttng_trigger_destroy(trigger);
4204 lttng_dynamic_buffer_reset(&trigger_buffer);
4205 return ret;
4206 }
4207
4208 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4209 struct notification_thread_handle *notification_thread)
4210 {
4211 int ret;
4212 size_t trigger_len;
4213 ssize_t sock_recv_len;
4214 struct lttng_trigger *trigger = NULL;
4215 struct lttng_buffer_view view;
4216 struct lttng_dynamic_buffer trigger_buffer;
4217
4218 lttng_dynamic_buffer_init(&trigger_buffer);
4219 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4220 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4221 if (ret) {
4222 ret = LTTNG_ERR_NOMEM;
4223 goto end;
4224 }
4225
4226 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4227 trigger_len);
4228 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4229 ERR("Failed to receive \"unregister trigger\" command payload");
4230 /* TODO: should this be a new error enum ? */
4231 ret = LTTNG_ERR_INVALID_TRIGGER;
4232 goto end;
4233 }
4234
4235 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4236 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4237 trigger_len) {
4238 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4239 ret = LTTNG_ERR_INVALID_TRIGGER;
4240 goto end;
4241 }
4242
4243 ret = notification_thread_command_unregister_trigger(notification_thread,
4244 trigger);
4245 end:
4246 lttng_trigger_destroy(trigger);
4247 lttng_dynamic_buffer_reset(&trigger_buffer);
4248 return ret;
4249 }
4250
4251 /*
4252 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4253 * snapshot output is *not* set with a remote destination.
4254 *
4255 * Return LTTNG_OK on success or a LTTNG_ERR code.
4256 */
4257 static enum lttng_error_code set_relayd_for_snapshot(
4258 struct consumer_output *output,
4259 const struct ltt_session *session)
4260 {
4261 enum lttng_error_code status = LTTNG_OK;
4262 struct lttng_ht_iter iter;
4263 struct consumer_socket *socket;
4264 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4265 const char *base_path;
4266
4267 assert(output);
4268 assert(session);
4269
4270 DBG2("Set relayd object from snapshot output");
4271
4272 if (session->current_trace_chunk) {
4273 enum lttng_trace_chunk_status chunk_status =
4274 lttng_trace_chunk_get_id(
4275 session->current_trace_chunk,
4276 &current_chunk_id.value);
4277
4278 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4279 current_chunk_id.is_set = true;
4280 } else {
4281 ERR("Failed to get current trace chunk id");
4282 status = LTTNG_ERR_UNK;
4283 goto error;
4284 }
4285 }
4286
4287 /* Ignore if snapshot consumer output is not network. */
4288 if (output->type != CONSUMER_DST_NET) {
4289 goto error;
4290 }
4291
4292 /*
4293 * The snapshot record URI base path overrides the session
4294 * base path.
4295 */
4296 if (output->dst.net.control.subdir[0] != '\0') {
4297 base_path = output->dst.net.control.subdir;
4298 } else {
4299 base_path = session->base_path;
4300 }
4301
4302 /*
4303 * For each consumer socket, create and send the relayd object of the
4304 * snapshot output.
4305 */
4306 rcu_read_lock();
4307 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4308 socket, node.node) {
4309 pthread_mutex_lock(socket->lock);
4310 status = send_consumer_relayd_sockets(0, session->id,
4311 output, socket,
4312 session->name, session->hostname,
4313 base_path,
4314 session->live_timer,
4315 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4316 session->creation_time,
4317 session->name_contains_creation_time);
4318 pthread_mutex_unlock(socket->lock);
4319 if (status != LTTNG_OK) {
4320 rcu_read_unlock();
4321 goto error;
4322 }
4323 }
4324 rcu_read_unlock();
4325
4326 error:
4327 return status;
4328 }
4329
4330 /*
4331 * Record a kernel snapshot.
4332 *
4333 * Return LTTNG_OK on success or a LTTNG_ERR code.
4334 */
4335 static enum lttng_error_code record_kernel_snapshot(
4336 struct ltt_kernel_session *ksess,
4337 const struct consumer_output *output,
4338 const struct ltt_session *session,
4339 int wait, uint64_t nb_packets_per_stream)
4340 {
4341 enum lttng_error_code status;
4342
4343 assert(ksess);
4344 assert(output);
4345 assert(session);
4346
4347 status = kernel_snapshot_record(
4348 ksess, output, wait, nb_packets_per_stream);
4349 return status;
4350 }
4351
4352 /*
4353 * Record a UST snapshot.
4354 *
4355 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4356 */
4357 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4358 const struct consumer_output *output,
4359 const struct ltt_session *session,
4360 int wait, uint64_t nb_packets_per_stream)
4361 {
4362 enum lttng_error_code status;
4363
4364 assert(usess);
4365 assert(output);
4366 assert(session);
4367
4368 status = ust_app_snapshot_record(
4369 usess, output, wait, nb_packets_per_stream);
4370 return status;
4371 }
4372
4373 static
4374 uint64_t get_session_size_one_more_packet_per_stream(
4375 const struct ltt_session *session, uint64_t cur_nr_packets)
4376 {
4377 uint64_t tot_size = 0;
4378
4379 if (session->kernel_session) {
4380 struct ltt_kernel_channel *chan;
4381 const struct ltt_kernel_session *ksess =
4382 session->kernel_session;
4383
4384 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4385 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4386 /*
4387 * Don't take channel into account if we
4388 * already grab all its packets.
4389 */
4390 continue;
4391 }
4392 tot_size += chan->channel->attr.subbuf_size
4393 * chan->stream_count;
4394 }
4395 }
4396
4397 if (session->ust_session) {
4398 const struct ltt_ust_session *usess = session->ust_session;
4399
4400 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4401 cur_nr_packets);
4402 }
4403
4404 return tot_size;
4405 }
4406
4407 /*
4408 * Calculate the number of packets we can grab from each stream that
4409 * fits within the overall snapshot max size.
4410 *
4411 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4412 * the number of packets per stream.
4413 *
4414 * TODO: this approach is not perfect: we consider the worse case
4415 * (packet filling the sub-buffers) as an upper bound, but we could do
4416 * better if we do this calculation while we actually grab the packet
4417 * content: we would know how much padding we don't actually store into
4418 * the file.
4419 *
4420 * This algorithm is currently bounded by the number of packets per
4421 * stream.
4422 *
4423 * Since we call this algorithm before actually grabbing the data, it's
4424 * an approximation: for instance, applications could appear/disappear
4425 * in between this call and actually grabbing data.
4426 */
4427 static
4428 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4429 uint64_t max_size)
4430 {
4431 int64_t size_left;
4432 uint64_t cur_nb_packets = 0;
4433
4434 if (!max_size) {
4435 return 0; /* Infinite */
4436 }
4437
4438 size_left = max_size;
4439 for (;;) {
4440 uint64_t one_more_packet_tot_size;
4441
4442 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4443 session, cur_nb_packets);
4444 if (!one_more_packet_tot_size) {
4445 /* We are already grabbing all packets. */
4446 break;
4447 }
4448 size_left -= one_more_packet_tot_size;
4449 if (size_left < 0) {
4450 break;
4451 }
4452 cur_nb_packets++;
4453 }
4454 if (!cur_nb_packets) {
4455 /* Not enough room to grab one packet of each stream, error. */
4456 return -1;
4457 }
4458 return cur_nb_packets;
4459 }
4460
4461 static
4462 enum lttng_error_code snapshot_record(struct ltt_session *session,
4463 const struct snapshot_output *snapshot_output, int wait)
4464 {
4465 int64_t nb_packets_per_stream;
4466 char snapshot_chunk_name[LTTNG_NAME_MAX];
4467 int ret;
4468 enum lttng_error_code ret_code = LTTNG_OK;
4469 struct lttng_trace_chunk *snapshot_trace_chunk;
4470 struct consumer_output *original_ust_consumer_output = NULL;
4471 struct consumer_output *original_kernel_consumer_output = NULL;
4472 struct consumer_output *snapshot_ust_consumer_output = NULL;
4473 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4474
4475 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4476 "%s-%s-%" PRIu64,
4477 snapshot_output->name,
4478 snapshot_output->datetime,
4479 snapshot_output->nb_snapshot);
4480 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4481 ERR("Failed to format snapshot name");
4482 ret_code = LTTNG_ERR_INVALID;
4483 goto error;
4484 }
4485 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4486 snapshot_output->name, session->name,
4487 snapshot_chunk_name);
4488 if (!session->kernel_session && !session->ust_session) {
4489 ERR("Failed to record snapshot as no channels exist");
4490 ret_code = LTTNG_ERR_NO_CHANNEL;
4491 goto error;
4492 }
4493
4494 if (session->kernel_session) {
4495 original_kernel_consumer_output =
4496 session->kernel_session->consumer;
4497 snapshot_kernel_consumer_output =
4498 consumer_copy_output(snapshot_output->consumer);
4499 strcpy(snapshot_kernel_consumer_output->chunk_path,
4500 snapshot_chunk_name);
4501 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4502 original_kernel_consumer_output);
4503 if (ret < 0) {
4504 ERR("Failed to copy consumer sockets from snapshot output configuration");
4505 ret_code = LTTNG_ERR_NOMEM;
4506 goto error;
4507 }
4508 ret_code = set_relayd_for_snapshot(
4509 snapshot_kernel_consumer_output, session);
4510 if (ret_code != LTTNG_OK) {
4511 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4512 goto error;
4513 }
4514 session->kernel_session->consumer =
4515 snapshot_kernel_consumer_output;
4516 }
4517 if (session->ust_session) {
4518 original_ust_consumer_output = session->ust_session->consumer;
4519 snapshot_ust_consumer_output =
4520 consumer_copy_output(snapshot_output->consumer);
4521 strcpy(snapshot_ust_consumer_output->chunk_path,
4522 snapshot_chunk_name);
4523 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4524 original_ust_consumer_output);
4525 if (ret < 0) {
4526 ERR("Failed to copy consumer sockets from snapshot output configuration");
4527 ret_code = LTTNG_ERR_NOMEM;
4528 goto error;
4529 }
4530 ret_code = set_relayd_for_snapshot(
4531 snapshot_ust_consumer_output, session);
4532 if (ret_code != LTTNG_OK) {
4533 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4534 goto error;
4535 }
4536 session->ust_session->consumer =
4537 snapshot_ust_consumer_output;
4538 }
4539
4540 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4541 snapshot_kernel_consumer_output ?:
4542 snapshot_ust_consumer_output,
4543 consumer_output_get_base_path(
4544 snapshot_output->consumer),
4545 snapshot_chunk_name);
4546 if (!snapshot_trace_chunk) {
4547 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
4548 session->name);
4549 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
4550 goto error;
4551 }
4552 assert(!session->current_trace_chunk);
4553 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4554 lttng_trace_chunk_put(snapshot_trace_chunk);
4555 snapshot_trace_chunk = NULL;
4556 if (ret) {
4557 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
4558 session->name);
4559 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4560 goto error;
4561 }
4562
4563 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4564 snapshot_output->max_size);
4565 if (nb_packets_per_stream < 0) {
4566 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
4567 goto error;
4568 }
4569
4570 if (session->kernel_session) {
4571 ret_code = record_kernel_snapshot(session->kernel_session,
4572 snapshot_kernel_consumer_output, session,
4573 wait, nb_packets_per_stream);
4574 if (ret_code != LTTNG_OK) {
4575 goto error;
4576 }
4577 }
4578
4579 if (session->ust_session) {
4580 ret_code = record_ust_snapshot(session->ust_session,
4581 snapshot_ust_consumer_output, session,
4582 wait, nb_packets_per_stream);
4583 if (ret_code != LTTNG_OK) {
4584 goto error;
4585 }
4586 }
4587
4588 if (session_close_trace_chunk(
4589 session, session->current_trace_chunk, NULL, NULL)) {
4590 /*
4591 * Don't goto end; make sure the chunk is closed for the session
4592 * to allow future snapshots.
4593 */
4594 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4595 session->name);
4596 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4597 }
4598 if (session_set_trace_chunk(session, NULL, NULL)) {
4599 ERR("Failed to release the current trace chunk of session \"%s\"",
4600 session->name);
4601 ret_code = LTTNG_ERR_UNK;
4602 }
4603 error:
4604 if (original_ust_consumer_output) {
4605 session->ust_session->consumer = original_ust_consumer_output;
4606 }
4607 if (original_kernel_consumer_output) {
4608 session->kernel_session->consumer =
4609 original_kernel_consumer_output;
4610 }
4611 consumer_output_put(snapshot_ust_consumer_output);
4612 consumer_output_put(snapshot_kernel_consumer_output);
4613 return ret_code;
4614 }
4615
4616 /*
4617 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4618 *
4619 * The wait parameter is ignored so this call always wait for the snapshot to
4620 * complete before returning.
4621 *
4622 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4623 */
4624 int cmd_snapshot_record(struct ltt_session *session,
4625 const struct lttng_snapshot_output *output, int wait)
4626 {
4627 enum lttng_error_code cmd_ret = LTTNG_OK;
4628 int ret;
4629 unsigned int snapshot_success = 0;
4630 char datetime[16];
4631 struct snapshot_output *tmp_output = NULL;
4632
4633 assert(session);
4634 assert(output);
4635
4636 DBG("Cmd snapshot record for session %s", session->name);
4637
4638 /* Get the datetime for the snapshot output directory. */
4639 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4640 sizeof(datetime));
4641 if (!ret) {
4642 cmd_ret = LTTNG_ERR_INVALID;
4643 goto error;
4644 }
4645
4646 /*
4647 * Permission denied to create an output if the session is not
4648 * set in no output mode.
4649 */
4650 if (session->output_traces) {
4651 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4652 goto error;
4653 }
4654
4655 /* The session needs to be started at least once. */
4656 if (!session->has_been_started) {
4657 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4658 goto error;
4659 }
4660
4661 /* Use temporary output for the session. */
4662 if (*output->ctrl_url != '\0') {
4663 tmp_output = snapshot_output_alloc();
4664 if (!tmp_output) {
4665 cmd_ret = LTTNG_ERR_NOMEM;
4666 goto error;
4667 }
4668
4669 ret = snapshot_output_init(session, output->max_size,
4670 output->name,
4671 output->ctrl_url, output->data_url,
4672 session->consumer,
4673 tmp_output, NULL);
4674 if (ret < 0) {
4675 if (ret == -ENOMEM) {
4676 cmd_ret = LTTNG_ERR_NOMEM;
4677 } else {
4678 cmd_ret = LTTNG_ERR_INVALID;
4679 }
4680 goto error;
4681 }
4682 /* Use the global session count for the temporary snapshot. */
4683 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
4684
4685 /* Use the global datetime */
4686 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
4687 cmd_ret = snapshot_record(session, tmp_output, wait);
4688 if (cmd_ret != LTTNG_OK) {
4689 goto error;
4690 }
4691 snapshot_success = 1;
4692 } else {
4693 struct snapshot_output *sout;
4694 struct lttng_ht_iter iter;
4695
4696 rcu_read_lock();
4697 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4698 &iter.iter, sout, node.node) {
4699 struct snapshot_output output_copy;
4700
4701 /*
4702 * Make a local copy of the output and override output
4703 * parameters with those provided as part of the
4704 * command.
4705 */
4706 memcpy(&output_copy, sout, sizeof(output_copy));
4707
4708 if (output->max_size != (uint64_t) -1ULL) {
4709 output_copy.max_size = output->max_size;
4710 }
4711
4712 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
4713 memcpy(output_copy.datetime, datetime,
4714 sizeof(datetime));
4715
4716 /* Use temporary name. */
4717 if (*output->name != '\0') {
4718 if (lttng_strncpy(output_copy.name,
4719 output->name,
4720 sizeof(output_copy.name))) {
4721 cmd_ret = LTTNG_ERR_INVALID;
4722 rcu_read_unlock();
4723 goto error;
4724 }
4725 }
4726
4727 cmd_ret = snapshot_record(session, &output_copy, wait);
4728 if (cmd_ret != LTTNG_OK) {
4729 rcu_read_unlock();
4730 goto error;
4731 }
4732 snapshot_success = 1;
4733 }
4734 rcu_read_unlock();
4735 }
4736
4737 if (snapshot_success) {
4738 session->snapshot.nb_snapshot++;
4739 } else {
4740 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4741 }
4742
4743 error:
4744 if (tmp_output) {
4745 snapshot_output_destroy(tmp_output);
4746 }
4747 return cmd_ret;
4748 }
4749
4750 /*
4751 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4752 */
4753 int cmd_set_session_shm_path(struct ltt_session *session,
4754 const char *shm_path)
4755 {
4756 /* Safety net */
4757 assert(session);
4758
4759 /*
4760 * Can only set shm path before session is started.
4761 */
4762 if (session->has_been_started) {
4763 return LTTNG_ERR_SESSION_STARTED;
4764 }
4765
4766 strncpy(session->shm_path, shm_path,
4767 sizeof(session->shm_path));
4768 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4769
4770 return 0;
4771 }
4772
4773 /*
4774 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4775 *
4776 * Ask the consumer to rotate the session output directory.
4777 * The session lock must be held.
4778 *
4779 * Returns LTTNG_OK on success or else a negative LTTng error code.
4780 */
4781 int cmd_rotate_session(struct ltt_session *session,
4782 struct lttng_rotate_session_return *rotate_return,
4783 bool quiet_rotation)
4784 {
4785 int ret;
4786 uint64_t ongoing_rotation_chunk_id;
4787 enum lttng_error_code cmd_ret = LTTNG_OK;
4788 struct lttng_trace_chunk *chunk_being_archived = NULL;
4789 struct lttng_trace_chunk *new_trace_chunk = NULL;
4790 enum lttng_trace_chunk_status chunk_status;
4791 bool failed_to_rotate = false;
4792 enum lttng_error_code rotation_fail_code = LTTNG_OK;
4793
4794 assert(session);
4795
4796 if (!session->has_been_started) {
4797 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4798 goto end;
4799 }
4800
4801 /*
4802 * Explicit rotation is not supported for live sessions.
4803 * However, live sessions can perform a quiet rotation on
4804 * destroy.
4805 * Rotation is not supported for snapshot traces (no output).
4806 */
4807 if ((!quiet_rotation && session->live_timer) ||
4808 !session->output_traces) {
4809 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4810 goto end;
4811 }
4812
4813 /* Unsupported feature in lttng-relayd before 2.11. */
4814 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
4815 (session->consumer->relay_major_version == 2 &&
4816 session->consumer->relay_minor_version < 11)) {
4817 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4818 goto end;
4819 }
4820
4821 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4822 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
4823 session->name);
4824 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
4825 goto end;
4826 }
4827
4828 /*
4829 * After a stop, we only allow one rotation to occur, the other ones are
4830 * useless until a new start.
4831 */
4832 if (session->rotated_after_last_stop) {
4833 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4834 session->name);
4835 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4836 goto end;
4837 }
4838
4839 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
4840
4841 if (session->active) {
4842 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
4843 NULL, NULL);
4844 if (!new_trace_chunk) {
4845 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
4846 goto error;
4847 }
4848 }
4849
4850 /*
4851 * The current trace chunk becomes the chunk being archived.
4852 *
4853 * After this point, "chunk_being_archived" must absolutely
4854 * be closed on the consumer(s), otherwise it will never be
4855 * cleaned-up, which will result in a leak.
4856 */
4857 ret = session_set_trace_chunk(session, new_trace_chunk,
4858 &chunk_being_archived);
4859 if (ret) {
4860 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4861 goto error;
4862 }
4863
4864 assert(chunk_being_archived);
4865 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
4866 &ongoing_rotation_chunk_id);
4867 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
4868
4869 if (session->kernel_session) {
4870 cmd_ret = kernel_rotate_session(session);
4871 if (cmd_ret != LTTNG_OK) {
4872 failed_to_rotate = true;
4873 rotation_fail_code = cmd_ret;
4874 }
4875 }
4876 if (session->ust_session) {
4877 cmd_ret = ust_app_rotate_session(session);
4878 if (cmd_ret != LTTNG_OK) {
4879 failed_to_rotate = true;
4880 rotation_fail_code = cmd_ret;
4881 }
4882 }
4883
4884 ret = session_close_trace_chunk(session, chunk_being_archived,
4885 quiet_rotation ?
4886 NULL :
4887 &((enum lttng_trace_chunk_command_type){
4888 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED}),
4889 session->last_chunk_path);
4890 if (ret) {
4891 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4892 goto error;
4893 }
4894
4895 if (failed_to_rotate) {
4896 cmd_ret = rotation_fail_code;
4897 goto error;
4898 }
4899
4900 session->quiet_rotation = quiet_rotation;
4901 ret = timer_session_rotation_pending_check_start(session,
4902 DEFAULT_ROTATE_PENDING_TIMER);
4903 if (ret) {
4904 cmd_ret = LTTNG_ERR_UNK;
4905 goto error;
4906 }
4907
4908 if (!session->active) {
4909 session->rotated_after_last_stop = true;
4910 }
4911
4912 if (rotate_return) {
4913 rotate_return->rotation_id = ongoing_rotation_chunk_id;
4914 }
4915
4916 session->chunk_being_archived = chunk_being_archived;
4917 chunk_being_archived = NULL;
4918 if (!quiet_rotation) {
4919 ret = notification_thread_command_session_rotation_ongoing(
4920 notification_thread_handle,
4921 session->name, session->uid, session->gid,
4922 ongoing_rotation_chunk_id);
4923 if (ret != LTTNG_OK) {
4924 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
4925 session->name);
4926 cmd_ret = ret;
4927 }
4928 }
4929
4930 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
4931 session->name, ongoing_rotation_chunk_id);
4932 end:
4933 lttng_trace_chunk_put(new_trace_chunk);
4934 lttng_trace_chunk_put(chunk_being_archived);
4935 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
4936 return ret;
4937 error:
4938 if (session_reset_rotation_state(session,
4939 LTTNG_ROTATION_STATE_ERROR)) {
4940 ERR("Failed to reset rotation state of session \"%s\"",
4941 session->name);
4942 }
4943 goto end;
4944 }
4945
4946 /*
4947 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
4948 *
4949 * Check if the session has finished its rotation.
4950 *
4951 * Return LTTNG_OK on success or else an LTTNG_ERR code.
4952 */
4953 int cmd_rotate_get_info(struct ltt_session *session,
4954 struct lttng_rotation_get_info_return *info_return,
4955 uint64_t rotation_id)
4956 {
4957 enum lttng_error_code cmd_ret = LTTNG_OK;
4958 enum lttng_rotation_state rotation_state;
4959
4960 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
4961 session->most_recent_chunk_id.value);
4962
4963 if (session->chunk_being_archived) {
4964 enum lttng_trace_chunk_status chunk_status;
4965 uint64_t chunk_id;
4966
4967 chunk_status = lttng_trace_chunk_get_id(
4968 session->chunk_being_archived,
4969 &chunk_id);
4970 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
4971
4972 rotation_state = rotation_id == chunk_id ?
4973 LTTNG_ROTATION_STATE_ONGOING :
4974 LTTNG_ROTATION_STATE_EXPIRED;
4975 } else {
4976 if (session->last_archived_chunk_id.is_set &&
4977 rotation_id != session->last_archived_chunk_id.value) {
4978 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
4979 } else {
4980 rotation_state = session->rotation_state;
4981 }
4982 }
4983
4984 switch (rotation_state) {
4985 case LTTNG_ROTATION_STATE_NO_ROTATION:
4986 DBG("Reporting that no rotation has occured within the lifetime of session \"%s\"",
4987 session->name);
4988 goto end;
4989 case LTTNG_ROTATION_STATE_EXPIRED:
4990 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
4991 rotation_id, session->name);
4992 break;
4993 case LTTNG_ROTATION_STATE_ONGOING:
4994 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
4995 rotation_id, session->name);
4996 break;
4997 case LTTNG_ROTATION_STATE_COMPLETED:
4998 {
4999 int fmt_ret;
5000 char *chunk_path;
5001 char *current_tracing_path_reply;
5002 size_t current_tracing_path_reply_len;
5003
5004 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5005 rotation_id, session->name);
5006
5007 switch (session_get_consumer_destination_type(session)) {
5008 case CONSUMER_DST_LOCAL:
5009 current_tracing_path_reply =
5010 info_return->location.local.absolute_path;
5011 current_tracing_path_reply_len =
5012 sizeof(info_return->location.local.absolute_path);
5013 info_return->location_type =
5014 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5015 fmt_ret = asprintf(&chunk_path,
5016 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5017 session_get_base_path(session),
5018 session->last_archived_chunk_name);
5019 if (fmt_ret == -1) {
5020 PERROR("Failed to format the path of the last archived trace chunk");
5021 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5022 cmd_ret = LTTNG_ERR_UNK;
5023 goto end;
5024 }
5025 break;
5026 case CONSUMER_DST_NET:
5027 {
5028 uint16_t ctrl_port, data_port;
5029
5030 current_tracing_path_reply =
5031 info_return->location.relay.relative_path;
5032 current_tracing_path_reply_len =
5033 sizeof(info_return->location.relay.relative_path);
5034 /* Currently the only supported relay protocol. */
5035 info_return->location.relay.protocol =
5036 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5037
5038 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5039 session_get_net_consumer_hostname(session),
5040 sizeof(info_return->location.relay.host));
5041 if (fmt_ret) {
5042 ERR("Failed to copy host name to rotate_get_info reply");
5043 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5044 cmd_ret = LTTNG_ERR_SET_URL;
5045 goto end;
5046 }
5047
5048 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5049 info_return->location.relay.ports.control = ctrl_port;
5050 info_return->location.relay.ports.data = data_port;
5051 info_return->location_type =
5052 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5053 chunk_path = strdup(session->last_chunk_path);
5054 if (!chunk_path) {
5055 ERR("Failed to allocate the path of the last archived trace chunk");
5056 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5057 cmd_ret = LTTNG_ERR_UNK;
5058 goto end;
5059 }
5060 break;
5061 }
5062 default:
5063 abort();
5064 }
5065
5066 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5067 chunk_path, current_tracing_path_reply_len);
5068 free(chunk_path);
5069 if (fmt_ret) {
5070 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5071 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5072 cmd_ret = LTTNG_ERR_UNK;
5073 goto end;
5074 }
5075
5076 break;
5077 }
5078 case LTTNG_ROTATION_STATE_ERROR:
5079 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5080 rotation_id, session->name);
5081 break;
5082 default:
5083 abort();
5084 }
5085
5086 cmd_ret = LTTNG_OK;
5087 end:
5088 info_return->status = (int32_t) rotation_state;
5089 return cmd_ret;
5090 }
5091
5092 /*
5093 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5094 *
5095 * Configure the automatic rotation parameters.
5096 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5097 * 'activate' to false means deactivate the rotation schedule and validate that
5098 * 'new_value' has the same value as the currently active value.
5099 *
5100 * Return 0 on success or else a positive LTTNG_ERR code.
5101 */
5102 int cmd_rotation_set_schedule(struct ltt_session *session,
5103 bool activate, enum lttng_rotation_schedule_type schedule_type,
5104 uint64_t new_value,
5105 struct notification_thread_handle *notification_thread_handle)
5106 {
5107 int ret;
5108 uint64_t *parameter_value;
5109
5110 assert(session);
5111
5112 DBG("Cmd rotate set schedule session %s", session->name);
5113
5114 if (session->live_timer || !session->output_traces) {
5115 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5116 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5117 goto end;
5118 }
5119
5120 switch (schedule_type) {
5121 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5122 parameter_value = &session->rotate_size;
5123 break;
5124 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5125 parameter_value = &session->rotate_timer_period;
5126 if (new_value >= UINT_MAX) {
5127 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5128 new_value, UINT_MAX);
5129 ret = LTTNG_ERR_INVALID;
5130 goto end;
5131 }
5132 break;
5133 default:
5134 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5135 ret = LTTNG_ERR_INVALID;
5136 goto end;
5137 }
5138
5139 /* Improper use of the API. */
5140 if (new_value == -1ULL) {
5141 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5142 ret = LTTNG_ERR_INVALID;
5143 goto end;
5144 }
5145
5146 /*
5147 * As indicated in struct ltt_session's comments, a value of == 0 means
5148 * this schedule rotation type is not in use.
5149 *
5150 * Reject the command if we were asked to activate a schedule that was
5151 * already active.
5152 */
5153 if (activate && *parameter_value != 0) {
5154 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5155 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5156 goto end;
5157 }
5158
5159 /*
5160 * Reject the command if we were asked to deactivate a schedule that was
5161 * not active.
5162 */
5163 if (!activate && *parameter_value == 0) {
5164 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5165 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5166 goto end;
5167 }
5168
5169 /*
5170 * Reject the command if we were asked to deactivate a schedule that
5171 * doesn't exist.
5172 */
5173 if (!activate && *parameter_value != new_value) {
5174 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5175 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5176 goto end;
5177 }
5178
5179 *parameter_value = activate ? new_value : 0;
5180
5181 switch (schedule_type) {
5182 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5183 if (activate && session->active) {
5184 /*
5185 * Only start the timer if the session is active,
5186 * otherwise it will be started when the session starts.
5187 */
5188 ret = timer_session_rotation_schedule_timer_start(
5189 session, new_value);
5190 if (ret) {
5191 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5192 ret = LTTNG_ERR_UNK;
5193 goto end;
5194 }
5195 } else {
5196 ret = timer_session_rotation_schedule_timer_stop(
5197 session);
5198 if (ret) {
5199 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5200 ret = LTTNG_ERR_UNK;
5201 goto end;
5202 }
5203 }
5204 break;
5205 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5206 if (activate) {
5207 ret = subscribe_session_consumed_size_rotation(session,
5208 new_value, notification_thread_handle);
5209 if (ret) {
5210 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5211 ret = LTTNG_ERR_UNK;
5212 goto end;
5213 }
5214 } else {
5215 ret = unsubscribe_session_consumed_size_rotation(session,
5216 notification_thread_handle);
5217 if (ret) {
5218 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5219 ret = LTTNG_ERR_UNK;
5220 goto end;
5221 }
5222
5223 }
5224 break;
5225 default:
5226 /* Would have been caught before. */
5227 abort();
5228 }
5229
5230 ret = LTTNG_OK;
5231
5232 goto end;
5233
5234 end:
5235 return ret;
5236 }
5237
5238 /* Wait for a given path to be removed before continuing. */
5239 static enum lttng_error_code wait_on_path(void *path_data)
5240 {
5241 const char *shm_path = path_data;
5242
5243 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5244 shm_path);
5245 while (true) {
5246 int ret;
5247 struct stat st;
5248
5249 ret = stat(shm_path, &st);
5250 if (ret) {
5251 if (errno != ENOENT) {
5252 PERROR("stat() returned an error while checking for the existence of the shm path");
5253 } else {
5254 DBG("shm path no longer exists, completing the destruction of session");
5255 }
5256 break;
5257 } else {
5258 if (!S_ISDIR(st.st_mode)) {
5259 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5260 shm_path);
5261 break;
5262 }
5263 }
5264 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5265 }
5266 return LTTNG_OK;
5267 }
5268
5269 /*
5270 * Returns a pointer to a handler to run on completion of a command.
5271 * Returns NULL if no handler has to be run for the last command executed.
5272 */
5273 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5274 {
5275 struct cmd_completion_handler *handler = current_completion_handler;
5276
5277 current_completion_handler = NULL;
5278 return handler;
5279 }
5280
5281 /*
5282 * Init command subsystem.
5283 */
5284 void cmd_init(void)
5285 {
5286 /*
5287 * Set network sequence index to 1 for streams to match a relayd
5288 * socket on the consumer side.
5289 */
5290 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5291 relayd_net_seq_idx = 1;
5292 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5293
5294 DBG("Command subsystem initialized");
5295 }
LTTng 2.0 tools and control repository
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