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Fix: sessiond: preserve jul/log4j domain loglevels
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.cpp
1 /*
2 * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * SPDX-License-Identifier: GPL-2.0-only
6 *
7 */
8
9 #define _LGPL_SOURCE
10 #include "agent-thread.hpp"
11 #include "agent.hpp"
12 #include "buffer-registry.hpp"
13 #include "channel.hpp"
14 #include "cmd.hpp"
15 #include "consumer.hpp"
16 #include "event-notifier-error-accounting.hpp"
17 #include "event.hpp"
18 #include "health-sessiond.hpp"
19 #include "kernel-consumer.hpp"
20 #include "kernel.hpp"
21 #include "lttng-sessiond.hpp"
22 #include "lttng-syscall.hpp"
23 #include "notification-thread-commands.hpp"
24 #include "notification-thread.hpp"
25 #include "rotation-thread.hpp"
26 #include "session.hpp"
27 #include "timer.hpp"
28 #include "tracker.hpp"
29 #include "utils.hpp"
30
31 #include <common/buffer-view.hpp>
32 #include <common/common.hpp>
33 #include <common/compat/string.hpp>
34 #include <common/defaults.hpp>
35 #include <common/dynamic-buffer.hpp>
36 #include <common/kernel-ctl/kernel-ctl.hpp>
37 #include <common/payload-view.hpp>
38 #include <common/payload.hpp>
39 #include <common/relayd/relayd.hpp>
40 #include <common/sessiond-comm/sessiond-comm.hpp>
41 #include <common/string-utils/string-utils.hpp>
42 #include <common/trace-chunk.hpp>
43 #include <common/urcu.hpp>
44 #include <common/utils.hpp>
45
46 #include <lttng/action/action-internal.hpp>
47 #include <lttng/action/action.h>
48 #include <lttng/channel-internal.hpp>
49 #include <lttng/channel.h>
50 #include <lttng/condition/condition-internal.hpp>
51 #include <lttng/condition/condition.h>
52 #include <lttng/condition/event-rule-matches-internal.hpp>
53 #include <lttng/condition/event-rule-matches.h>
54 #include <lttng/error-query-internal.hpp>
55 #include <lttng/event-internal.hpp>
56 #include <lttng/event-rule/event-rule-internal.hpp>
57 #include <lttng/event-rule/event-rule.h>
58 #include <lttng/location-internal.hpp>
59 #include <lttng/lttng-error.h>
60 #include <lttng/rotate-internal.hpp>
61 #include <lttng/session-descriptor-internal.hpp>
62 #include <lttng/session-internal.hpp>
63 #include <lttng/tracker.h>
64 #include <lttng/trigger/trigger-internal.hpp>
65 #include <lttng/userspace-probe-internal.hpp>
66
67 #include <algorithm>
68 #include <inttypes.h>
69 #include <stdio.h>
70 #include <sys/stat.h>
71 #include <urcu/list.h>
72 #include <urcu/uatomic.h>
73
74 /* Sleep for 100ms between each check for the shm path's deletion. */
75 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
76
77 namespace lsu = lttng::sessiond::ust;
78
79 static enum lttng_error_code wait_on_path(void *path);
80
81 namespace {
82 struct cmd_destroy_session_reply_context {
83 int reply_sock_fd;
84 bool implicit_rotation_on_destroy;
85 /*
86 * Indicates whether or not an error occurred while launching the
87 * destruction of a session.
88 */
89 enum lttng_error_code destruction_status;
90 };
91
92 /*
93 * Command completion handler that is used by the destroy command
94 * when a session that has a non-default shm_path is being destroyed.
95 *
96 * See comment in cmd_destroy_session() for the rationale.
97 */
98 struct destroy_completion_handler {
99 struct cmd_completion_handler handler;
100 char shm_path[member_sizeof(struct ltt_session, shm_path)];
101 } destroy_completion_handler = {
102 .handler = { .run = wait_on_path, .data = destroy_completion_handler.shm_path },
103 .shm_path = { 0 },
104 };
105
106 /*
107 * Used to keep a unique index for each relayd socket created where this value
108 * is associated with streams on the consumer so it can match the right relayd
109 * to send to. It must be accessed with the relayd_net_seq_idx_lock
110 * held.
111 */
112 pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
113 uint64_t relayd_net_seq_idx;
114 } /* namespace */
115
116 static struct cmd_completion_handler *current_completion_handler;
117 static int validate_ust_event_name(const char *);
118 static int cmd_enable_event_internal(struct ltt_session *session,
119 const struct lttng_domain *domain,
120 char *channel_name,
121 struct lttng_event *event,
122 char *filter_expression,
123 struct lttng_bytecode *filter,
124 struct lttng_event_exclusion *exclusion,
125 int wpipe);
126 static enum lttng_error_code cmd_enable_channel_internal(struct ltt_session *session,
127 const struct lttng_domain *domain,
128 const struct lttng_channel *_attr,
129 int wpipe);
130
131 /*
132 * Create a session path used by list_lttng_sessions for the case that the
133 * session consumer is on the network.
134 */
135 static int build_network_session_path(char *dst, size_t size, struct ltt_session *session)
136 {
137 int ret, kdata_port, udata_port;
138 struct lttng_uri *kuri = nullptr, *uuri = nullptr, *uri = nullptr;
139 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
140
141 LTTNG_ASSERT(session);
142 LTTNG_ASSERT(dst);
143
144 memset(tmp_urls, 0, sizeof(tmp_urls));
145 memset(tmp_uurl, 0, sizeof(tmp_uurl));
146
147 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
148
149 if (session->kernel_session && session->kernel_session->consumer) {
150 kuri = &session->kernel_session->consumer->dst.net.control;
151 kdata_port = session->kernel_session->consumer->dst.net.data.port;
152 }
153
154 if (session->ust_session && session->ust_session->consumer) {
155 uuri = &session->ust_session->consumer->dst.net.control;
156 udata_port = session->ust_session->consumer->dst.net.data.port;
157 }
158
159 if (uuri == nullptr && kuri == nullptr) {
160 uri = &session->consumer->dst.net.control;
161 kdata_port = session->consumer->dst.net.data.port;
162 } else if (kuri && uuri) {
163 ret = uri_compare(kuri, uuri);
164 if (ret) {
165 /* Not Equal */
166 uri = kuri;
167 /* Build uuri URL string */
168 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
169 if (ret < 0) {
170 goto error;
171 }
172 } else {
173 uri = kuri;
174 }
175 } else if (kuri && uuri == nullptr) {
176 uri = kuri;
177 } else if (uuri && kuri == nullptr) {
178 uri = uuri;
179 }
180
181 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
182 if (ret < 0) {
183 goto error;
184 }
185
186 /*
187 * Do we have a UST url set. If yes, this means we have both kernel and UST
188 * to print.
189 */
190 if (*tmp_uurl != '\0') {
191 ret = snprintf(dst,
192 size,
193 "[K]: %s [data: %d] -- [U]: %s [data: %d]",
194 tmp_urls,
195 kdata_port,
196 tmp_uurl,
197 udata_port);
198 } else {
199 int dport;
200 if (kuri || (!kuri && !uuri)) {
201 dport = kdata_port;
202 } else {
203 /* No kernel URI, use the UST port. */
204 dport = udata_port;
205 }
206 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
207 }
208
209 error:
210 return ret;
211 }
212
213 /*
214 * Get run-time attributes if the session has been started (discarded events,
215 * lost packets).
216 */
217 static int get_kernel_runtime_stats(struct ltt_session *session,
218 struct ltt_kernel_channel *kchan,
219 uint64_t *discarded_events,
220 uint64_t *lost_packets)
221 {
222 int ret;
223
224 if (!session->has_been_started) {
225 ret = 0;
226 *discarded_events = 0;
227 *lost_packets = 0;
228 goto end;
229 }
230
231 ret = consumer_get_discarded_events(
232 session->id, kchan->key, session->kernel_session->consumer, discarded_events);
233 if (ret < 0) {
234 goto end;
235 }
236
237 ret = consumer_get_lost_packets(
238 session->id, kchan->key, session->kernel_session->consumer, lost_packets);
239 if (ret < 0) {
240 goto end;
241 }
242
243 end:
244 return ret;
245 }
246
247 /*
248 * Get run-time attributes if the session has been started (discarded events,
249 * lost packets).
250 */
251 static int get_ust_runtime_stats(struct ltt_session *session,
252 struct ltt_ust_channel *uchan,
253 uint64_t *discarded_events,
254 uint64_t *lost_packets)
255 {
256 int ret;
257 struct ltt_ust_session *usess;
258
259 if (!discarded_events || !lost_packets) {
260 ret = -1;
261 goto end;
262 }
263
264 usess = session->ust_session;
265 LTTNG_ASSERT(discarded_events);
266 LTTNG_ASSERT(lost_packets);
267
268 if (!usess || !session->has_been_started) {
269 *discarded_events = 0;
270 *lost_packets = 0;
271 ret = 0;
272 goto end;
273 }
274
275 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
276 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
277 &usess->buffer_reg_uid_list,
278 usess->consumer,
279 uchan->id,
280 uchan->attr.overwrite,
281 discarded_events,
282 lost_packets);
283 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
284 ret = ust_app_pid_get_channel_runtime_stats(usess,
285 uchan,
286 usess->consumer,
287 uchan->attr.overwrite,
288 discarded_events,
289 lost_packets);
290 if (ret < 0) {
291 goto end;
292 }
293 *discarded_events += uchan->per_pid_closed_app_discarded;
294 *lost_packets += uchan->per_pid_closed_app_lost;
295 } else {
296 ERR("Unsupported buffer type");
297 abort();
298 ret = -1;
299 goto end;
300 }
301
302 end:
303 return ret;
304 }
305
306 /*
307 * Create a list of agent domain events.
308 *
309 * Return number of events in list on success or else a negative value.
310 */
311 static enum lttng_error_code list_lttng_agent_events(struct agent *agt,
312 struct lttng_payload *reply_payload,
313 unsigned int *nb_events)
314 {
315 enum lttng_error_code ret_code;
316 int ret = 0;
317 unsigned int local_nb_events = 0;
318 struct agent_event *event;
319 struct lttng_ht_iter iter;
320 unsigned long agent_event_count;
321
322 assert(agt);
323 assert(reply_payload);
324
325 DBG3("Listing agent events");
326
327 agent_event_count = lttng_ht_get_count(agt->events);
328 if (agent_event_count == 0) {
329 /* Early exit. */
330 goto end;
331 }
332
333 if (agent_event_count > UINT_MAX) {
334 ret_code = LTTNG_ERR_OVERFLOW;
335 goto error;
336 }
337
338 local_nb_events = (unsigned int) agent_event_count;
339
340 {
341 lttng::urcu::read_lock_guard read_lock;
342
343 cds_lfht_for_each_entry (agt->events->ht, &iter.iter, event, node.node) {
344 struct lttng_event *tmp_event = lttng_event_create();
345
346 if (!tmp_event) {
347 ret_code = LTTNG_ERR_NOMEM;
348 goto error;
349 }
350
351 if (lttng_strncpy(tmp_event->name, event->name, sizeof(tmp_event->name))) {
352 lttng_event_destroy(tmp_event);
353 ret_code = LTTNG_ERR_FATAL;
354 goto error;
355 }
356
357 tmp_event->name[sizeof(tmp_event->name) - 1] = '\0';
358 tmp_event->enabled = !!event->enabled_count;
359 tmp_event->loglevel = event->loglevel_value;
360 tmp_event->loglevel_type = event->loglevel_type;
361
362 ret = lttng_event_serialize(tmp_event,
363 0,
364 nullptr,
365 event->filter_expression,
366 0,
367 nullptr,
368 reply_payload);
369 lttng_event_destroy(tmp_event);
370 if (ret) {
371 ret_code = LTTNG_ERR_FATAL;
372 goto error;
373 }
374 }
375 }
376 end:
377 ret_code = LTTNG_OK;
378 *nb_events = local_nb_events;
379 error:
380 return ret_code;
381 }
382
383 /*
384 * Create a list of ust global domain events.
385 */
386 static enum lttng_error_code list_lttng_ust_global_events(char *channel_name,
387 struct ltt_ust_domain_global *ust_global,
388 struct lttng_payload *reply_payload,
389 unsigned int *nb_events)
390 {
391 enum lttng_error_code ret_code;
392 int ret;
393 struct lttng_ht_iter iter;
394 struct lttng_ht_node_str *node;
395 struct ltt_ust_channel *uchan;
396 struct ltt_ust_event *uevent;
397 unsigned long channel_event_count;
398 unsigned int local_nb_events = 0;
399
400 assert(reply_payload);
401 assert(nb_events);
402
403 DBG("Listing UST global events for channel %s", channel_name);
404
405 lttng::urcu::read_lock_guard read_lock;
406
407 lttng_ht_lookup(ust_global->channels, (void *) channel_name, &iter);
408 node = lttng_ht_iter_get_node_str(&iter);
409 if (node == nullptr) {
410 ret_code = LTTNG_ERR_UST_CHAN_NOT_FOUND;
411 goto error;
412 }
413
414 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
415
416 channel_event_count = lttng_ht_get_count(uchan->events);
417 if (channel_event_count == 0) {
418 /* Early exit. */
419 ret_code = LTTNG_OK;
420 goto end;
421 }
422
423 if (channel_event_count > UINT_MAX) {
424 ret_code = LTTNG_ERR_OVERFLOW;
425 goto error;
426 }
427
428 local_nb_events = (unsigned int) channel_event_count;
429
430 DBG3("Listing UST global %d events", *nb_events);
431
432 cds_lfht_for_each_entry (uchan->events->ht, &iter.iter, uevent, node.node) {
433 struct lttng_event *tmp_event = nullptr;
434
435 if (uevent->internal) {
436 /* This event should remain hidden from clients */
437 local_nb_events--;
438 continue;
439 }
440
441 tmp_event = lttng_event_create();
442 if (!tmp_event) {
443 ret_code = LTTNG_ERR_NOMEM;
444 goto error;
445 }
446
447 if (lttng_strncpy(tmp_event->name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN)) {
448 ret_code = LTTNG_ERR_FATAL;
449 lttng_event_destroy(tmp_event);
450 goto error;
451 }
452
453 tmp_event->name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
454 tmp_event->enabled = uevent->enabled;
455
456 switch (uevent->attr.instrumentation) {
457 case LTTNG_UST_ABI_TRACEPOINT:
458 tmp_event->type = LTTNG_EVENT_TRACEPOINT;
459 break;
460 case LTTNG_UST_ABI_PROBE:
461 tmp_event->type = LTTNG_EVENT_PROBE;
462 break;
463 case LTTNG_UST_ABI_FUNCTION:
464 tmp_event->type = LTTNG_EVENT_FUNCTION;
465 break;
466 }
467
468 tmp_event->loglevel = uevent->attr.loglevel;
469 switch (uevent->attr.loglevel_type) {
470 case LTTNG_UST_ABI_LOGLEVEL_ALL:
471 tmp_event->loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
472 break;
473 case LTTNG_UST_ABI_LOGLEVEL_RANGE:
474 tmp_event->loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
475 break;
476 case LTTNG_UST_ABI_LOGLEVEL_SINGLE:
477 tmp_event->loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
478 break;
479 }
480 if (uevent->filter) {
481 tmp_event->filter = 1;
482 }
483 if (uevent->exclusion) {
484 tmp_event->exclusion = 1;
485 }
486
487 std::vector<const char *> exclusion_names;
488 if (uevent->exclusion) {
489 for (int i = 0; i < uevent->exclusion->count; i++) {
490 exclusion_names.emplace_back(
491 LTTNG_EVENT_EXCLUSION_NAME_AT(uevent->exclusion, i));
492 }
493 }
494
495 /*
496 * We do not care about the filter bytecode and the fd from the
497 * userspace_probe_location.
498 */
499 ret = lttng_event_serialize(tmp_event,
500 exclusion_names.size(),
501 exclusion_names.size() ? exclusion_names.data() :
502 nullptr,
503 uevent->filter_expression,
504 0,
505 nullptr,
506 reply_payload);
507 lttng_event_destroy(tmp_event);
508 if (ret) {
509 ret_code = LTTNG_ERR_FATAL;
510 goto error;
511 }
512 }
513
514 end:
515 /* nb_events is already set at this point. */
516 ret_code = LTTNG_OK;
517 *nb_events = local_nb_events;
518 error:
519 return ret_code;
520 }
521
522 /*
523 * Fill lttng_event array of all kernel events in the channel.
524 */
525 static enum lttng_error_code list_lttng_kernel_events(char *channel_name,
526 struct ltt_kernel_session *kernel_session,
527 struct lttng_payload *reply_payload,
528 unsigned int *nb_events)
529 {
530 enum lttng_error_code ret_code;
531 int ret;
532 struct ltt_kernel_event *event;
533 struct ltt_kernel_channel *kchan;
534
535 assert(reply_payload);
536
537 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
538 if (kchan == nullptr) {
539 ret_code = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
540 goto end;
541 }
542
543 *nb_events = kchan->event_count;
544
545 DBG("Listing events for channel %s", kchan->channel->name);
546
547 if (*nb_events == 0) {
548 ret_code = LTTNG_OK;
549 goto end;
550 }
551
552 /* Kernel channels */
553 cds_list_for_each_entry (event, &kchan->events_list.head, list) {
554 struct lttng_event *tmp_event = lttng_event_create();
555
556 if (!tmp_event) {
557 ret_code = LTTNG_ERR_NOMEM;
558 goto end;
559 }
560
561 if (lttng_strncpy(tmp_event->name, event->event->name, LTTNG_SYMBOL_NAME_LEN)) {
562 lttng_event_destroy(tmp_event);
563 ret_code = LTTNG_ERR_FATAL;
564 goto end;
565 }
566
567 tmp_event->name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
568 tmp_event->enabled = event->enabled;
569 tmp_event->filter = (unsigned char) !!event->filter_expression;
570
571 switch (event->event->instrumentation) {
572 case LTTNG_KERNEL_ABI_TRACEPOINT:
573 tmp_event->type = LTTNG_EVENT_TRACEPOINT;
574 break;
575 case LTTNG_KERNEL_ABI_KRETPROBE:
576 tmp_event->type = LTTNG_EVENT_FUNCTION;
577 memcpy(&tmp_event->attr.probe,
578 &event->event->u.kprobe,
579 sizeof(struct lttng_kernel_abi_kprobe));
580 break;
581 case LTTNG_KERNEL_ABI_KPROBE:
582 tmp_event->type = LTTNG_EVENT_PROBE;
583 memcpy(&tmp_event->attr.probe,
584 &event->event->u.kprobe,
585 sizeof(struct lttng_kernel_abi_kprobe));
586 break;
587 case LTTNG_KERNEL_ABI_UPROBE:
588 tmp_event->type = LTTNG_EVENT_USERSPACE_PROBE;
589 break;
590 case LTTNG_KERNEL_ABI_FUNCTION:
591 tmp_event->type = LTTNG_EVENT_FUNCTION;
592 memcpy(&(tmp_event->attr.ftrace),
593 &event->event->u.ftrace,
594 sizeof(struct lttng_kernel_abi_function));
595 break;
596 case LTTNG_KERNEL_ABI_NOOP:
597 tmp_event->type = LTTNG_EVENT_NOOP;
598 break;
599 case LTTNG_KERNEL_ABI_SYSCALL:
600 tmp_event->type = LTTNG_EVENT_SYSCALL;
601 break;
602 case LTTNG_KERNEL_ABI_ALL:
603 /* fall-through. */
604 default:
605 abort();
606 break;
607 }
608
609 if (event->userspace_probe_location) {
610 struct lttng_userspace_probe_location *location_copy =
611 lttng_userspace_probe_location_copy(
612 event->userspace_probe_location);
613
614 if (!location_copy) {
615 lttng_event_destroy(tmp_event);
616 ret_code = LTTNG_ERR_NOMEM;
617 goto end;
618 }
619
620 ret = lttng_event_set_userspace_probe_location(tmp_event, location_copy);
621 if (ret) {
622 lttng_event_destroy(tmp_event);
623 lttng_userspace_probe_location_destroy(location_copy);
624 ret_code = LTTNG_ERR_INVALID;
625 goto end;
626 }
627 }
628
629 ret = lttng_event_serialize(
630 tmp_event, 0, nullptr, event->filter_expression, 0, nullptr, reply_payload);
631 lttng_event_destroy(tmp_event);
632 if (ret) {
633 ret_code = LTTNG_ERR_FATAL;
634 goto end;
635 }
636 }
637
638 ret_code = LTTNG_OK;
639 end:
640 return ret_code;
641 }
642
643 /*
644 * Add URI so the consumer output object. Set the correct path depending on the
645 * domain adding the default trace directory.
646 */
647 static enum lttng_error_code add_uri_to_consumer(const struct ltt_session *session,
648 struct consumer_output *consumer,
649 struct lttng_uri *uri,
650 enum lttng_domain_type domain)
651 {
652 int ret;
653 enum lttng_error_code ret_code = LTTNG_OK;
654
655 LTTNG_ASSERT(uri);
656
657 if (consumer == nullptr) {
658 DBG("No consumer detected. Don't add URI. Stopping.");
659 ret_code = LTTNG_ERR_NO_CONSUMER;
660 goto error;
661 }
662
663 switch (domain) {
664 case LTTNG_DOMAIN_KERNEL:
665 ret = lttng_strncpy(consumer->domain_subdir,
666 DEFAULT_KERNEL_TRACE_DIR,
667 sizeof(consumer->domain_subdir));
668 break;
669 case LTTNG_DOMAIN_UST:
670 ret = lttng_strncpy(consumer->domain_subdir,
671 DEFAULT_UST_TRACE_DIR,
672 sizeof(consumer->domain_subdir));
673 break;
674 default:
675 /*
676 * This case is possible is we try to add the URI to the global
677 * tracing session consumer object which in this case there is
678 * no subdir.
679 */
680 memset(consumer->domain_subdir, 0, sizeof(consumer->domain_subdir));
681 ret = 0;
682 }
683 if (ret) {
684 ERR("Failed to initialize consumer output domain subdirectory");
685 ret_code = LTTNG_ERR_FATAL;
686 goto error;
687 }
688
689 switch (uri->dtype) {
690 case LTTNG_DST_IPV4:
691 case LTTNG_DST_IPV6:
692 DBG2("Setting network URI to consumer");
693
694 if (consumer->type == CONSUMER_DST_NET) {
695 if ((uri->stype == LTTNG_STREAM_CONTROL &&
696 consumer->dst.net.control_isset) ||
697 (uri->stype == LTTNG_STREAM_DATA && consumer->dst.net.data_isset)) {
698 ret_code = LTTNG_ERR_URL_EXIST;
699 goto error;
700 }
701 } else {
702 memset(&consumer->dst, 0, sizeof(consumer->dst));
703 }
704
705 /* Set URI into consumer output object */
706 ret = consumer_set_network_uri(session, consumer, uri);
707 if (ret < 0) {
708 ret_code = (lttng_error_code) -ret;
709 goto error;
710 } else if (ret == 1) {
711 /*
712 * URI was the same in the consumer so we do not append the subdir
713 * again so to not duplicate output dir.
714 */
715 ret_code = LTTNG_OK;
716 goto error;
717 }
718 break;
719 case LTTNG_DST_PATH:
720 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
721 ret_code = LTTNG_ERR_INVALID;
722 goto error;
723 }
724 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
725 memset(&consumer->dst, 0, sizeof(consumer->dst));
726
727 ret = lttng_strncpy(consumer->dst.session_root_path,
728 uri->dst.path,
729 sizeof(consumer->dst.session_root_path));
730 if (ret) {
731 ret_code = LTTNG_ERR_FATAL;
732 goto error;
733 }
734 consumer->type = CONSUMER_DST_LOCAL;
735 break;
736 }
737
738 ret_code = LTTNG_OK;
739 error:
740 return ret_code;
741 }
742
743 /*
744 * Init tracing by creating trace directory and sending fds kernel consumer.
745 */
746 static int init_kernel_tracing(struct ltt_kernel_session *session)
747 {
748 int ret = 0;
749 struct lttng_ht_iter iter;
750 struct consumer_socket *socket;
751
752 LTTNG_ASSERT(session);
753
754 if (session->consumer_fds_sent == 0 && session->consumer != nullptr) {
755 lttng::urcu::read_lock_guard read_lock;
756
757 cds_lfht_for_each_entry (
758 session->consumer->socks->ht, &iter.iter, socket, node.node) {
759 pthread_mutex_lock(socket->lock);
760 ret = kernel_consumer_send_session(socket, session);
761 pthread_mutex_unlock(socket->lock);
762 if (ret < 0) {
763 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
764 goto error;
765 }
766 }
767 }
768
769 error:
770 return ret;
771 }
772
773 /*
774 * Create a socket to the relayd using the URI.
775 *
776 * On success, the relayd_sock pointer is set to the created socket.
777 * Else, it remains untouched and an LTTng error code is returned.
778 */
779 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
780 struct lttcomm_relayd_sock **relayd_sock,
781 struct consumer_output *consumer)
782 {
783 int ret;
784 enum lttng_error_code status = LTTNG_OK;
785 struct lttcomm_relayd_sock *rsock;
786
787 rsock = lttcomm_alloc_relayd_sock(
788 uri, RELAYD_VERSION_COMM_MAJOR, RELAYD_VERSION_COMM_MINOR);
789 if (!rsock) {
790 status = LTTNG_ERR_FATAL;
791 goto error;
792 }
793
794 /*
795 * Connect to relayd so we can proceed with a session creation. This call
796 * can possibly block for an arbitrary amount of time to set the health
797 * state to be in poll execution.
798 */
799 health_poll_entry();
800 ret = relayd_connect(rsock);
801 health_poll_exit();
802 if (ret < 0) {
803 ERR("Unable to reach lttng-relayd");
804 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
805 goto free_sock;
806 }
807
808 /* Create socket for control stream. */
809 if (uri->stype == LTTNG_STREAM_CONTROL) {
810 uint64_t result_flags;
811
812 DBG3("Creating relayd stream socket from URI");
813
814 /* Check relayd version */
815 ret = relayd_version_check(rsock);
816 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
817 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
818 goto close_sock;
819 } else if (ret < 0) {
820 ERR("Unable to reach lttng-relayd");
821 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
822 goto close_sock;
823 }
824 consumer->relay_major_version = rsock->major;
825 consumer->relay_minor_version = rsock->minor;
826 ret = relayd_get_configuration(rsock, 0, &result_flags);
827 if (ret < 0) {
828 ERR("Unable to get relayd configuration");
829 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
830 goto close_sock;
831 }
832 if (result_flags & LTTCOMM_RELAYD_CONFIGURATION_FLAG_CLEAR_ALLOWED) {
833 consumer->relay_allows_clear = true;
834 }
835 } else if (uri->stype == LTTNG_STREAM_DATA) {
836 DBG3("Creating relayd data socket from URI");
837 } else {
838 /* Command is not valid */
839 ERR("Relayd invalid stream type: %d", uri->stype);
840 status = LTTNG_ERR_INVALID;
841 goto close_sock;
842 }
843
844 *relayd_sock = rsock;
845
846 return status;
847
848 close_sock:
849 /* The returned value is not useful since we are on an error path. */
850 (void) relayd_close(rsock);
851 free_sock:
852 free(rsock);
853 error:
854 return status;
855 }
856
857 /*
858 * Connect to the relayd using URI and send the socket to the right consumer.
859 *
860 * The consumer socket lock must be held by the caller.
861 *
862 * Returns LTTNG_OK on success or an LTTng error code on failure.
863 */
864 static enum lttng_error_code send_consumer_relayd_socket(unsigned int session_id,
865 struct lttng_uri *relayd_uri,
866 struct consumer_output *consumer,
867 struct consumer_socket *consumer_sock,
868 const char *session_name,
869 const char *hostname,
870 const char *base_path,
871 int session_live_timer,
872 const uint64_t *current_chunk_id,
873 time_t session_creation_time,
874 bool session_name_contains_creation_time)
875 {
876 int ret;
877 struct lttcomm_relayd_sock *rsock = nullptr;
878 enum lttng_error_code status;
879
880 /* Connect to relayd and make version check if uri is the control. */
881 status = create_connect_relayd(relayd_uri, &rsock, consumer);
882 if (status != LTTNG_OK) {
883 goto relayd_comm_error;
884 }
885 LTTNG_ASSERT(rsock);
886
887 /* Set the network sequence index if not set. */
888 if (consumer->net_seq_index == (uint64_t) -1ULL) {
889 pthread_mutex_lock(&relayd_net_seq_idx_lock);
890 /*
891 * Increment net_seq_idx because we are about to transfer the
892 * new relayd socket to the consumer.
893 * Assign unique key so the consumer can match streams.
894 */
895 consumer->net_seq_index = ++relayd_net_seq_idx;
896 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
897 }
898
899 /* Send relayd socket to consumer. */
900 ret = consumer_send_relayd_socket(consumer_sock,
901 rsock,
902 consumer,
903 relayd_uri->stype,
904 session_id,
905 session_name,
906 hostname,
907 base_path,
908 session_live_timer,
909 current_chunk_id,
910 session_creation_time,
911 session_name_contains_creation_time);
912 if (ret < 0) {
913 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
914 goto close_sock;
915 }
916
917 /* Flag that the corresponding socket was sent. */
918 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
919 consumer_sock->control_sock_sent = 1;
920 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
921 consumer_sock->data_sock_sent = 1;
922 }
923
924 /*
925 * Close socket which was dup on the consumer side. The session daemon does
926 * NOT keep track of the relayd socket(s) once transfer to the consumer.
927 */
928
929 close_sock:
930 if (status != LTTNG_OK) {
931 /*
932 * The consumer output for this session should not be used anymore
933 * since the relayd connection failed thus making any tracing or/and
934 * streaming not usable.
935 */
936 consumer->enabled = false;
937 }
938 (void) relayd_close(rsock);
939 free(rsock);
940
941 relayd_comm_error:
942 return status;
943 }
944
945 /*
946 * Send both relayd sockets to a specific consumer and domain. This is a
947 * helper function to facilitate sending the information to the consumer for a
948 * session.
949 *
950 * The consumer socket lock must be held by the caller.
951 *
952 * Returns LTTNG_OK, or an LTTng error code on failure.
953 */
954 static enum lttng_error_code send_consumer_relayd_sockets(unsigned int session_id,
955 struct consumer_output *consumer,
956 struct consumer_socket *sock,
957 const char *session_name,
958 const char *hostname,
959 const char *base_path,
960 int session_live_timer,
961 const uint64_t *current_chunk_id,
962 time_t session_creation_time,
963 bool session_name_contains_creation_time)
964 {
965 enum lttng_error_code status = LTTNG_OK;
966
967 LTTNG_ASSERT(consumer);
968 LTTNG_ASSERT(sock);
969
970 /* Sending control relayd socket. */
971 if (!sock->control_sock_sent) {
972 status = send_consumer_relayd_socket(session_id,
973 &consumer->dst.net.control,
974 consumer,
975 sock,
976 session_name,
977 hostname,
978 base_path,
979 session_live_timer,
980 current_chunk_id,
981 session_creation_time,
982 session_name_contains_creation_time);
983 if (status != LTTNG_OK) {
984 goto error;
985 }
986 }
987
988 /* Sending data relayd socket. */
989 if (!sock->data_sock_sent) {
990 status = send_consumer_relayd_socket(session_id,
991 &consumer->dst.net.data,
992 consumer,
993 sock,
994 session_name,
995 hostname,
996 base_path,
997 session_live_timer,
998 current_chunk_id,
999 session_creation_time,
1000 session_name_contains_creation_time);
1001 if (status != LTTNG_OK) {
1002 goto error;
1003 }
1004 }
1005
1006 error:
1007 return status;
1008 }
1009
1010 /*
1011 * Setup relayd connections for a tracing session. First creates the socket to
1012 * the relayd and send them to the right domain consumer. Consumer type MUST be
1013 * network.
1014 */
1015 int cmd_setup_relayd(struct ltt_session *session)
1016 {
1017 int ret = LTTNG_OK;
1018 struct ltt_ust_session *usess;
1019 struct ltt_kernel_session *ksess;
1020 struct consumer_socket *socket;
1021 struct lttng_ht_iter iter;
1022 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1023
1024 LTTNG_ASSERT(session);
1025
1026 usess = session->ust_session;
1027 ksess = session->kernel_session;
1028
1029 DBG("Setting relayd for session %s", session->name);
1030
1031 if (session->current_trace_chunk) {
1032 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1033 session->current_trace_chunk, &current_chunk_id.value);
1034
1035 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1036 current_chunk_id.is_set = true;
1037 } else {
1038 ERR("Failed to get current trace chunk id");
1039 ret = LTTNG_ERR_UNK;
1040 goto error;
1041 }
1042 }
1043
1044 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET &&
1045 usess->consumer->enabled) {
1046 /* For each consumer socket, send relayd sockets */
1047 lttng::urcu::read_lock_guard read_lock;
1048
1049 cds_lfht_for_each_entry (
1050 usess->consumer->socks->ht, &iter.iter, socket, node.node) {
1051 pthread_mutex_lock(socket->lock);
1052 ret = send_consumer_relayd_sockets(
1053 session->id,
1054 usess->consumer,
1055 socket,
1056 session->name,
1057 session->hostname,
1058 session->base_path,
1059 session->live_timer,
1060 current_chunk_id.is_set ? &current_chunk_id.value : nullptr,
1061 session->creation_time,
1062 session->name_contains_creation_time);
1063 pthread_mutex_unlock(socket->lock);
1064 if (ret != LTTNG_OK) {
1065 goto error;
1066 }
1067 /* Session is now ready for network streaming. */
1068 session->net_handle = 1;
1069 }
1070
1071 session->consumer->relay_major_version = usess->consumer->relay_major_version;
1072 session->consumer->relay_minor_version = usess->consumer->relay_minor_version;
1073 session->consumer->relay_allows_clear = usess->consumer->relay_allows_clear;
1074 }
1075
1076 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET &&
1077 ksess->consumer->enabled) {
1078 lttng::urcu::read_lock_guard read_lock;
1079
1080 cds_lfht_for_each_entry (
1081 ksess->consumer->socks->ht, &iter.iter, socket, node.node) {
1082 pthread_mutex_lock(socket->lock);
1083 ret = send_consumer_relayd_sockets(
1084 session->id,
1085 ksess->consumer,
1086 socket,
1087 session->name,
1088 session->hostname,
1089 session->base_path,
1090 session->live_timer,
1091 current_chunk_id.is_set ? &current_chunk_id.value : nullptr,
1092 session->creation_time,
1093 session->name_contains_creation_time);
1094 pthread_mutex_unlock(socket->lock);
1095 if (ret != LTTNG_OK) {
1096 goto error;
1097 }
1098 /* Session is now ready for network streaming. */
1099 session->net_handle = 1;
1100 }
1101
1102 session->consumer->relay_major_version = ksess->consumer->relay_major_version;
1103 session->consumer->relay_minor_version = ksess->consumer->relay_minor_version;
1104 session->consumer->relay_allows_clear = ksess->consumer->relay_allows_clear;
1105 }
1106
1107 error:
1108 return ret;
1109 }
1110
1111 /*
1112 * Start a kernel session by opening all necessary streams.
1113 */
1114 int start_kernel_session(struct ltt_kernel_session *ksess)
1115 {
1116 int ret;
1117 struct ltt_kernel_channel *kchan;
1118
1119 /* Open kernel metadata */
1120 if (ksess->metadata == nullptr && ksess->output_traces) {
1121 ret = kernel_open_metadata(ksess);
1122 if (ret < 0) {
1123 ret = LTTNG_ERR_KERN_META_FAIL;
1124 goto error;
1125 }
1126 }
1127
1128 /* Open kernel metadata stream */
1129 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1130 ret = kernel_open_metadata_stream(ksess);
1131 if (ret < 0) {
1132 ERR("Kernel create metadata stream failed");
1133 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1134 goto error;
1135 }
1136 }
1137
1138 /* For each channel */
1139 cds_list_for_each_entry (kchan, &ksess->channel_list.head, list) {
1140 if (kchan->stream_count == 0) {
1141 ret = kernel_open_channel_stream(kchan);
1142 if (ret < 0) {
1143 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1144 goto error;
1145 }
1146 /* Update the stream global counter */
1147 ksess->stream_count_global += ret;
1148 }
1149 }
1150
1151 /* Setup kernel consumer socket and send fds to it */
1152 ret = init_kernel_tracing(ksess);
1153 if (ret != 0) {
1154 ret = LTTNG_ERR_KERN_START_FAIL;
1155 goto error;
1156 }
1157
1158 /* This start the kernel tracing */
1159 ret = kernel_start_session(ksess);
1160 if (ret < 0) {
1161 ret = LTTNG_ERR_KERN_START_FAIL;
1162 goto error;
1163 }
1164
1165 /* Quiescent wait after starting trace */
1166 kernel_wait_quiescent();
1167
1168 ksess->active = true;
1169
1170 ret = LTTNG_OK;
1171
1172 error:
1173 return ret;
1174 }
1175
1176 int stop_kernel_session(struct ltt_kernel_session *ksess)
1177 {
1178 struct ltt_kernel_channel *kchan;
1179 bool error_occurred = false;
1180 int ret;
1181
1182 if (!ksess || !ksess->active) {
1183 return LTTNG_OK;
1184 }
1185 DBG("Stopping kernel tracing");
1186
1187 ret = kernel_stop_session(ksess);
1188 if (ret < 0) {
1189 ret = LTTNG_ERR_KERN_STOP_FAIL;
1190 goto error;
1191 }
1192
1193 kernel_wait_quiescent();
1194
1195 /* Flush metadata after stopping (if exists) */
1196 if (ksess->metadata_stream_fd >= 0) {
1197 ret = kernel_metadata_flush_buffer(ksess->metadata_stream_fd);
1198 if (ret < 0) {
1199 ERR("Kernel metadata flush failed");
1200 error_occurred = true;
1201 }
1202 }
1203
1204 /* Flush all buffers after stopping */
1205 cds_list_for_each_entry (kchan, &ksess->channel_list.head, list) {
1206 ret = kernel_flush_buffer(kchan);
1207 if (ret < 0) {
1208 ERR("Kernel flush buffer error");
1209 error_occurred = true;
1210 }
1211 }
1212
1213 ksess->active = false;
1214 if (error_occurred) {
1215 ret = LTTNG_ERR_UNK;
1216 } else {
1217 ret = LTTNG_OK;
1218 }
1219 error:
1220 return ret;
1221 }
1222
1223 /*
1224 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1225 */
1226 int cmd_disable_channel(struct ltt_session *session,
1227 enum lttng_domain_type domain,
1228 char *channel_name)
1229 {
1230 int ret;
1231 struct ltt_ust_session *usess;
1232
1233 usess = session->ust_session;
1234
1235 lttng::urcu::read_lock_guard read_lock;
1236
1237 switch (domain) {
1238 case LTTNG_DOMAIN_KERNEL:
1239 {
1240 ret = channel_kernel_disable(session->kernel_session, channel_name);
1241 if (ret != LTTNG_OK) {
1242 goto error;
1243 }
1244
1245 kernel_wait_quiescent();
1246 break;
1247 }
1248 case LTTNG_DOMAIN_UST:
1249 {
1250 struct ltt_ust_channel *uchan;
1251 struct lttng_ht *chan_ht;
1252
1253 chan_ht = usess->domain_global.channels;
1254
1255 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1256 if (uchan == nullptr) {
1257 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1258 goto error;
1259 }
1260
1261 ret = channel_ust_disable(usess, uchan);
1262 if (ret != LTTNG_OK) {
1263 goto error;
1264 }
1265 break;
1266 }
1267 default:
1268 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1269 goto error;
1270 }
1271
1272 ret = LTTNG_OK;
1273
1274 error:
1275 return ret;
1276 }
1277
1278 /*
1279 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1280 *
1281 * The wpipe arguments is used as a notifier for the kernel thread.
1282 */
1283 int cmd_enable_channel(struct command_ctx *cmd_ctx, int sock, int wpipe)
1284 {
1285 int ret;
1286 size_t channel_len;
1287 ssize_t sock_recv_len;
1288 struct lttng_channel *channel = nullptr;
1289 struct lttng_buffer_view view;
1290 struct lttng_dynamic_buffer channel_buffer;
1291 const struct lttng_domain command_domain = cmd_ctx->lsm.domain;
1292
1293 lttng_dynamic_buffer_init(&channel_buffer);
1294 channel_len = (size_t) cmd_ctx->lsm.u.channel.length;
1295 ret = lttng_dynamic_buffer_set_size(&channel_buffer, channel_len);
1296 if (ret) {
1297 ret = LTTNG_ERR_NOMEM;
1298 goto end;
1299 }
1300
1301 sock_recv_len = lttcomm_recv_unix_sock(sock, channel_buffer.data, channel_len);
1302 if (sock_recv_len < 0 || sock_recv_len != channel_len) {
1303 ERR("Failed to receive \"enable channel\" command payload");
1304 ret = LTTNG_ERR_INVALID;
1305 goto end;
1306 }
1307
1308 view = lttng_buffer_view_from_dynamic_buffer(&channel_buffer, 0, channel_len);
1309 if (!lttng_buffer_view_is_valid(&view)) {
1310 ret = LTTNG_ERR_INVALID;
1311 goto end;
1312 }
1313
1314 if (lttng_channel_create_from_buffer(&view, &channel) != channel_len) {
1315 ERR("Invalid channel payload received in \"enable channel\" command");
1316 ret = LTTNG_ERR_INVALID;
1317 goto end;
1318 }
1319
1320 ret = cmd_enable_channel_internal(cmd_ctx->session, &command_domain, channel, wpipe);
1321
1322 end:
1323 lttng_dynamic_buffer_reset(&channel_buffer);
1324 lttng_channel_destroy(channel);
1325 return ret;
1326 }
1327
1328 static enum lttng_error_code cmd_enable_channel_internal(struct ltt_session *session,
1329 const struct lttng_domain *domain,
1330 const struct lttng_channel *_attr,
1331 int wpipe)
1332 {
1333 enum lttng_error_code ret_code;
1334 struct ltt_ust_session *usess = session->ust_session;
1335 struct lttng_ht *chan_ht;
1336 size_t len;
1337 struct lttng_channel *attr = nullptr;
1338
1339 LTTNG_ASSERT(session);
1340 LTTNG_ASSERT(_attr);
1341 LTTNG_ASSERT(domain);
1342
1343 lttng::urcu::read_lock_guard read_lock;
1344
1345 attr = lttng_channel_copy(_attr);
1346 if (!attr) {
1347 ret_code = LTTNG_ERR_NOMEM;
1348 goto end;
1349 }
1350
1351 len = lttng_strnlen(attr->name, sizeof(attr->name));
1352
1353 /* Validate channel name */
1354 if (attr->name[0] == '.' || memchr(attr->name, '/', len) != nullptr) {
1355 ret_code = LTTNG_ERR_INVALID_CHANNEL_NAME;
1356 goto end;
1357 }
1358
1359 DBG("Enabling channel %s for session %s", attr->name, session->name);
1360
1361 /*
1362 * If the session is a live session, remove the switch timer, the
1363 * live timer does the same thing but sends also synchronisation
1364 * beacons for inactive streams.
1365 */
1366 if (session->live_timer > 0) {
1367 attr->attr.live_timer_interval = session->live_timer;
1368 attr->attr.switch_timer_interval = 0;
1369 }
1370
1371 /* Check for feature support */
1372 switch (domain->type) {
1373 case LTTNG_DOMAIN_KERNEL:
1374 {
1375 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1376 /* Sampling position of buffer is not supported */
1377 WARN("Kernel tracer does not support buffer monitoring. "
1378 "Setting the monitor interval timer to 0 "
1379 "(disabled) for channel '%s' of session '%s'",
1380 attr->name,
1381 session->name);
1382 lttng_channel_set_monitor_timer_interval(attr, 0);
1383 }
1384 break;
1385 }
1386 case LTTNG_DOMAIN_UST:
1387 break;
1388 case LTTNG_DOMAIN_JUL:
1389 case LTTNG_DOMAIN_LOG4J:
1390 case LTTNG_DOMAIN_PYTHON:
1391 if (!agent_tracing_is_enabled()) {
1392 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1393 ret_code = LTTNG_ERR_AGENT_TRACING_DISABLED;
1394 goto error;
1395 }
1396 break;
1397 default:
1398 ret_code = LTTNG_ERR_UNKNOWN_DOMAIN;
1399 goto error;
1400 }
1401
1402 switch (domain->type) {
1403 case LTTNG_DOMAIN_KERNEL:
1404 {
1405 struct ltt_kernel_channel *kchan;
1406
1407 kchan = trace_kernel_get_channel_by_name(attr->name, session->kernel_session);
1408 if (kchan == nullptr) {
1409 /*
1410 * Don't try to create a channel if the session has been started at
1411 * some point in time before. The tracer does not allow it.
1412 */
1413 if (session->has_been_started) {
1414 ret_code = LTTNG_ERR_TRACE_ALREADY_STARTED;
1415 goto error;
1416 }
1417
1418 if (session->snapshot.nb_output > 0 || session->snapshot_mode) {
1419 /* Enforce mmap output for snapshot sessions. */
1420 attr->attr.output = LTTNG_EVENT_MMAP;
1421 }
1422 ret_code = channel_kernel_create(session->kernel_session, attr, wpipe);
1423 if (attr->name[0] != '\0') {
1424 session->kernel_session->has_non_default_channel = 1;
1425 }
1426 } else {
1427 ret_code = channel_kernel_enable(session->kernel_session, kchan);
1428 }
1429
1430 if (ret_code != LTTNG_OK) {
1431 goto error;
1432 }
1433
1434 kernel_wait_quiescent();
1435 break;
1436 }
1437 case LTTNG_DOMAIN_UST:
1438 case LTTNG_DOMAIN_JUL:
1439 case LTTNG_DOMAIN_LOG4J:
1440 case LTTNG_DOMAIN_PYTHON:
1441 {
1442 struct ltt_ust_channel *uchan;
1443
1444 /*
1445 * FIXME
1446 *
1447 * Current agent implementation limitations force us to allow
1448 * only one channel at once in "agent" subdomains. Each
1449 * subdomain has a default channel name which must be strictly
1450 * adhered to.
1451 */
1452 if (domain->type == LTTNG_DOMAIN_JUL) {
1453 if (strncmp(attr->name,
1454 DEFAULT_JUL_CHANNEL_NAME,
1455 LTTNG_SYMBOL_NAME_LEN - 1) != 0) {
1456 ret_code = LTTNG_ERR_INVALID_CHANNEL_NAME;
1457 goto error;
1458 }
1459 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1460 if (strncmp(attr->name,
1461 DEFAULT_LOG4J_CHANNEL_NAME,
1462 LTTNG_SYMBOL_NAME_LEN - 1) != 0) {
1463 ret_code = LTTNG_ERR_INVALID_CHANNEL_NAME;
1464 goto error;
1465 }
1466 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1467 if (strncmp(attr->name,
1468 DEFAULT_PYTHON_CHANNEL_NAME,
1469 LTTNG_SYMBOL_NAME_LEN - 1) != 0) {
1470 ret_code = LTTNG_ERR_INVALID_CHANNEL_NAME;
1471 goto error;
1472 }
1473 }
1474
1475 chan_ht = usess->domain_global.channels;
1476
1477 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1478 if (uchan == nullptr) {
1479 /*
1480 * Don't try to create a channel if the session has been started at
1481 * some point in time before. The tracer does not allow it.
1482 */
1483 if (session->has_been_started) {
1484 ret_code = LTTNG_ERR_TRACE_ALREADY_STARTED;
1485 goto error;
1486 }
1487
1488 ret_code = channel_ust_create(usess, attr, domain->buf_type);
1489 if (attr->name[0] != '\0') {
1490 usess->has_non_default_channel = 1;
1491 }
1492 } else {
1493 ret_code = channel_ust_enable(usess, uchan);
1494 }
1495 break;
1496 }
1497 default:
1498 ret_code = LTTNG_ERR_UNKNOWN_DOMAIN;
1499 goto error;
1500 }
1501
1502 if (ret_code == LTTNG_OK && attr->attr.output != LTTNG_EVENT_MMAP) {
1503 session->has_non_mmap_channel = true;
1504 }
1505 error:
1506 end:
1507 lttng_channel_destroy(attr);
1508 return ret_code;
1509 }
1510
1511 enum lttng_error_code
1512 cmd_process_attr_tracker_get_tracking_policy(struct ltt_session *session,
1513 enum lttng_domain_type domain,
1514 enum lttng_process_attr process_attr,
1515 enum lttng_tracking_policy *policy)
1516 {
1517 enum lttng_error_code ret_code = LTTNG_OK;
1518 const struct process_attr_tracker *tracker;
1519
1520 switch (domain) {
1521 case LTTNG_DOMAIN_KERNEL:
1522 if (!session->kernel_session) {
1523 ret_code = LTTNG_ERR_INVALID;
1524 goto end;
1525 }
1526 tracker = kernel_get_process_attr_tracker(session->kernel_session, process_attr);
1527 break;
1528 case LTTNG_DOMAIN_UST:
1529 if (!session->ust_session) {
1530 ret_code = LTTNG_ERR_INVALID;
1531 goto end;
1532 }
1533 tracker = trace_ust_get_process_attr_tracker(session->ust_session, process_attr);
1534 break;
1535 default:
1536 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1537 goto end;
1538 }
1539 if (tracker) {
1540 *policy = process_attr_tracker_get_tracking_policy(tracker);
1541 } else {
1542 ret_code = LTTNG_ERR_INVALID;
1543 }
1544 end:
1545 return ret_code;
1546 }
1547
1548 enum lttng_error_code
1549 cmd_process_attr_tracker_set_tracking_policy(struct ltt_session *session,
1550 enum lttng_domain_type domain,
1551 enum lttng_process_attr process_attr,
1552 enum lttng_tracking_policy policy)
1553 {
1554 enum lttng_error_code ret_code = LTTNG_OK;
1555
1556 switch (policy) {
1557 case LTTNG_TRACKING_POLICY_INCLUDE_SET:
1558 case LTTNG_TRACKING_POLICY_EXCLUDE_ALL:
1559 case LTTNG_TRACKING_POLICY_INCLUDE_ALL:
1560 break;
1561 default:
1562 ret_code = LTTNG_ERR_INVALID;
1563 goto end;
1564 }
1565
1566 switch (domain) {
1567 case LTTNG_DOMAIN_KERNEL:
1568 if (!session->kernel_session) {
1569 ret_code = LTTNG_ERR_INVALID;
1570 goto end;
1571 }
1572 ret_code = kernel_process_attr_tracker_set_tracking_policy(
1573 session->kernel_session, process_attr, policy);
1574 break;
1575 case LTTNG_DOMAIN_UST:
1576 if (!session->ust_session) {
1577 ret_code = LTTNG_ERR_INVALID;
1578 goto end;
1579 }
1580 ret_code = trace_ust_process_attr_tracker_set_tracking_policy(
1581 session->ust_session, process_attr, policy);
1582 break;
1583 default:
1584 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1585 break;
1586 }
1587 end:
1588 return ret_code;
1589 }
1590
1591 enum lttng_error_code
1592 cmd_process_attr_tracker_inclusion_set_add_value(struct ltt_session *session,
1593 enum lttng_domain_type domain,
1594 enum lttng_process_attr process_attr,
1595 const struct process_attr_value *value)
1596 {
1597 enum lttng_error_code ret_code = LTTNG_OK;
1598
1599 switch (domain) {
1600 case LTTNG_DOMAIN_KERNEL:
1601 if (!session->kernel_session) {
1602 ret_code = LTTNG_ERR_INVALID;
1603 goto end;
1604 }
1605 ret_code = kernel_process_attr_tracker_inclusion_set_add_value(
1606 session->kernel_session, process_attr, value);
1607 break;
1608 case LTTNG_DOMAIN_UST:
1609 if (!session->ust_session) {
1610 ret_code = LTTNG_ERR_INVALID;
1611 goto end;
1612 }
1613 ret_code = trace_ust_process_attr_tracker_inclusion_set_add_value(
1614 session->ust_session, process_attr, value);
1615 break;
1616 default:
1617 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1618 break;
1619 }
1620 end:
1621 return ret_code;
1622 }
1623
1624 enum lttng_error_code
1625 cmd_process_attr_tracker_inclusion_set_remove_value(struct ltt_session *session,
1626 enum lttng_domain_type domain,
1627 enum lttng_process_attr process_attr,
1628 const struct process_attr_value *value)
1629 {
1630 enum lttng_error_code ret_code = LTTNG_OK;
1631
1632 switch (domain) {
1633 case LTTNG_DOMAIN_KERNEL:
1634 if (!session->kernel_session) {
1635 ret_code = LTTNG_ERR_INVALID;
1636 goto end;
1637 }
1638 ret_code = kernel_process_attr_tracker_inclusion_set_remove_value(
1639 session->kernel_session, process_attr, value);
1640 break;
1641 case LTTNG_DOMAIN_UST:
1642 if (!session->ust_session) {
1643 ret_code = LTTNG_ERR_INVALID;
1644 goto end;
1645 }
1646 ret_code = trace_ust_process_attr_tracker_inclusion_set_remove_value(
1647 session->ust_session, process_attr, value);
1648 break;
1649 default:
1650 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1651 break;
1652 }
1653 end:
1654 return ret_code;
1655 }
1656
1657 enum lttng_error_code
1658 cmd_process_attr_tracker_get_inclusion_set(struct ltt_session *session,
1659 enum lttng_domain_type domain,
1660 enum lttng_process_attr process_attr,
1661 struct lttng_process_attr_values **values)
1662 {
1663 enum lttng_error_code ret_code = LTTNG_OK;
1664 const struct process_attr_tracker *tracker;
1665 enum process_attr_tracker_status status;
1666
1667 switch (domain) {
1668 case LTTNG_DOMAIN_KERNEL:
1669 if (!session->kernel_session) {
1670 ret_code = LTTNG_ERR_INVALID;
1671 goto end;
1672 }
1673 tracker = kernel_get_process_attr_tracker(session->kernel_session, process_attr);
1674 break;
1675 case LTTNG_DOMAIN_UST:
1676 if (!session->ust_session) {
1677 ret_code = LTTNG_ERR_INVALID;
1678 goto end;
1679 }
1680 tracker = trace_ust_get_process_attr_tracker(session->ust_session, process_attr);
1681 break;
1682 default:
1683 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1684 goto end;
1685 }
1686
1687 if (!tracker) {
1688 ret_code = LTTNG_ERR_INVALID;
1689 goto end;
1690 }
1691
1692 status = process_attr_tracker_get_inclusion_set(tracker, values);
1693 switch (status) {
1694 case PROCESS_ATTR_TRACKER_STATUS_OK:
1695 ret_code = LTTNG_OK;
1696 break;
1697 case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY:
1698 ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY;
1699 break;
1700 case PROCESS_ATTR_TRACKER_STATUS_ERROR:
1701 ret_code = LTTNG_ERR_NOMEM;
1702 break;
1703 default:
1704 ret_code = LTTNG_ERR_UNK;
1705 break;
1706 }
1707
1708 end:
1709 return ret_code;
1710 }
1711
1712 /*
1713 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1714 */
1715 int cmd_disable_event(struct command_ctx *cmd_ctx,
1716 struct lttng_event *event,
1717 char *filter_expression,
1718 struct lttng_bytecode *bytecode,
1719 struct lttng_event_exclusion *exclusion)
1720 {
1721 int ret;
1722 const char *event_name;
1723 const struct ltt_session *session = cmd_ctx->session;
1724 const char *channel_name = cmd_ctx->lsm.u.disable.channel_name;
1725 const enum lttng_domain_type domain = cmd_ctx->lsm.domain.type;
1726
1727 DBG("Disable event command for event \'%s\'", event->name);
1728
1729 /*
1730 * Filter and exclusions are simply not handled by the
1731 * disable event command at this time.
1732 *
1733 * FIXME
1734 */
1735 (void) filter_expression;
1736 (void) exclusion;
1737
1738 /* Ignore the presence of filter or exclusion for the event */
1739 event->filter = 0;
1740 event->exclusion = 0;
1741
1742 event_name = event->name;
1743
1744 lttng::urcu::read_lock_guard read_lock;
1745
1746 /* Error out on unhandled search criteria */
1747 if (event->loglevel_type || event->loglevel != -1 || event->enabled || event->pid ||
1748 event->filter || event->exclusion) {
1749 ret = LTTNG_ERR_UNK;
1750 goto error;
1751 }
1752
1753 switch (domain) {
1754 case LTTNG_DOMAIN_KERNEL:
1755 {
1756 struct ltt_kernel_channel *kchan;
1757 struct ltt_kernel_session *ksess;
1758
1759 ksess = session->kernel_session;
1760
1761 /*
1762 * If a non-default channel has been created in the
1763 * session, explicitely require that -c chan_name needs
1764 * to be provided.
1765 */
1766 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1767 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1768 goto error_unlock;
1769 }
1770
1771 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1772 if (kchan == nullptr) {
1773 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1774 goto error_unlock;
1775 }
1776
1777 switch (event->type) {
1778 case LTTNG_EVENT_ALL:
1779 case LTTNG_EVENT_TRACEPOINT:
1780 case LTTNG_EVENT_SYSCALL:
1781 case LTTNG_EVENT_PROBE:
1782 case LTTNG_EVENT_FUNCTION:
1783 case LTTNG_EVENT_FUNCTION_ENTRY: /* fall-through */
1784 if (event_name[0] == '\0') {
1785 ret = event_kernel_disable_event(kchan, nullptr, event->type);
1786 } else {
1787 ret = event_kernel_disable_event(kchan, event_name, event->type);
1788 }
1789 if (ret != LTTNG_OK) {
1790 goto error_unlock;
1791 }
1792 break;
1793 default:
1794 ret = LTTNG_ERR_UNK;
1795 goto error_unlock;
1796 }
1797
1798 kernel_wait_quiescent();
1799 break;
1800 }
1801 case LTTNG_DOMAIN_UST:
1802 {
1803 struct ltt_ust_channel *uchan;
1804 struct ltt_ust_session *usess;
1805
1806 usess = session->ust_session;
1807
1808 if (validate_ust_event_name(event_name)) {
1809 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1810 goto error_unlock;
1811 }
1812
1813 /*
1814 * If a non-default channel has been created in the
1815 * session, explicitly require that -c chan_name needs
1816 * to be provided.
1817 */
1818 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1819 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1820 goto error_unlock;
1821 }
1822
1823 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels, channel_name);
1824 if (uchan == nullptr) {
1825 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1826 goto error_unlock;
1827 }
1828
1829 switch (event->type) {
1830 case LTTNG_EVENT_ALL:
1831 /*
1832 * An empty event name means that everything
1833 * should be disabled.
1834 */
1835 if (event->name[0] == '\0') {
1836 ret = event_ust_disable_all_tracepoints(usess, uchan);
1837 } else {
1838 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1839 }
1840 if (ret != LTTNG_OK) {
1841 goto error_unlock;
1842 }
1843 break;
1844 default:
1845 ret = LTTNG_ERR_UNK;
1846 goto error_unlock;
1847 }
1848
1849 DBG3("Disable UST event %s in channel %s completed", event_name, channel_name);
1850 break;
1851 }
1852 case LTTNG_DOMAIN_LOG4J:
1853 case LTTNG_DOMAIN_JUL:
1854 case LTTNG_DOMAIN_PYTHON:
1855 {
1856 struct agent *agt;
1857 struct ltt_ust_session *usess = session->ust_session;
1858
1859 LTTNG_ASSERT(usess);
1860
1861 switch (event->type) {
1862 case LTTNG_EVENT_ALL:
1863 break;
1864 default:
1865 ret = LTTNG_ERR_UNK;
1866 goto error_unlock;
1867 }
1868
1869 agt = trace_ust_find_agent(usess, domain);
1870 if (!agt) {
1871 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1872 goto error_unlock;
1873 }
1874 /*
1875 * An empty event name means that everything
1876 * should be disabled.
1877 */
1878 if (event->name[0] == '\0') {
1879 ret = event_agent_disable_all(usess, agt);
1880 } else {
1881 ret = event_agent_disable(usess, agt, event_name);
1882 }
1883 if (ret != LTTNG_OK) {
1884 goto error_unlock;
1885 }
1886
1887 break;
1888 }
1889 default:
1890 ret = LTTNG_ERR_UND;
1891 goto error_unlock;
1892 }
1893
1894 ret = LTTNG_OK;
1895
1896 error_unlock:
1897 error:
1898 free(exclusion);
1899 free(bytecode);
1900 free(filter_expression);
1901 return ret;
1902 }
1903
1904 /*
1905 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1906 */
1907 int cmd_add_context(struct command_ctx *cmd_ctx,
1908 const struct lttng_event_context *event_context,
1909 int kwpipe)
1910 {
1911 int ret, chan_kern_created = 0, chan_ust_created = 0;
1912 const enum lttng_domain_type domain = cmd_ctx->lsm.domain.type;
1913 const struct ltt_session *session = cmd_ctx->session;
1914 const char *channel_name = cmd_ctx->lsm.u.context.channel_name;
1915
1916 /*
1917 * Don't try to add a context if the session has been started at
1918 * some point in time before. The tracer does not allow it and would
1919 * result in a corrupted trace.
1920 */
1921 if (cmd_ctx->session->has_been_started) {
1922 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1923 goto end;
1924 }
1925
1926 switch (domain) {
1927 case LTTNG_DOMAIN_KERNEL:
1928 LTTNG_ASSERT(session->kernel_session);
1929
1930 if (session->kernel_session->channel_count == 0) {
1931 /* Create default channel */
1932 ret = channel_kernel_create(session->kernel_session, nullptr, kwpipe);
1933 if (ret != LTTNG_OK) {
1934 goto error;
1935 }
1936 chan_kern_created = 1;
1937 }
1938 /* Add kernel context to kernel tracer */
1939 ret = context_kernel_add(session->kernel_session, event_context, channel_name);
1940 if (ret != LTTNG_OK) {
1941 goto error;
1942 }
1943 break;
1944 case LTTNG_DOMAIN_JUL:
1945 case LTTNG_DOMAIN_LOG4J:
1946 {
1947 /*
1948 * Validate channel name.
1949 * If no channel name is given and the domain is JUL or LOG4J,
1950 * set it to the appropriate domain-specific channel name. If
1951 * a name is provided but does not match the expexted channel
1952 * name, return an error.
1953 */
1954 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1955 strcmp(channel_name, DEFAULT_JUL_CHANNEL_NAME) != 0) {
1956 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1957 goto error;
1958 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1959 strcmp(channel_name, DEFAULT_LOG4J_CHANNEL_NAME) != 0) {
1960 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1961 goto error;
1962 }
1963 }
1964 /* fall through */
1965 case LTTNG_DOMAIN_UST:
1966 {
1967 struct ltt_ust_session *usess = session->ust_session;
1968 unsigned int chan_count;
1969
1970 LTTNG_ASSERT(usess);
1971
1972 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1973 if (chan_count == 0) {
1974 struct lttng_channel *attr;
1975 /* Create default channel */
1976 attr = channel_new_default_attr(domain, usess->buffer_type);
1977 if (attr == nullptr) {
1978 ret = LTTNG_ERR_FATAL;
1979 goto error;
1980 }
1981
1982 ret = channel_ust_create(usess, attr, usess->buffer_type);
1983 if (ret != LTTNG_OK) {
1984 free(attr);
1985 goto error;
1986 }
1987 channel_attr_destroy(attr);
1988 chan_ust_created = 1;
1989 }
1990
1991 ret = context_ust_add(usess, domain, event_context, channel_name);
1992 if (ret != LTTNG_OK) {
1993 goto error;
1994 }
1995 break;
1996 }
1997 default:
1998 ret = LTTNG_ERR_UND;
1999 goto error;
2000 }
2001
2002 ret = LTTNG_OK;
2003 goto end;
2004
2005 error:
2006 if (chan_kern_created) {
2007 struct ltt_kernel_channel *kchan = trace_kernel_get_channel_by_name(
2008 DEFAULT_CHANNEL_NAME, session->kernel_session);
2009 /* Created previously, this should NOT fail. */
2010 LTTNG_ASSERT(kchan);
2011 kernel_destroy_channel(kchan);
2012 }
2013
2014 if (chan_ust_created) {
2015 struct ltt_ust_channel *uchan = trace_ust_find_channel_by_name(
2016 session->ust_session->domain_global.channels, DEFAULT_CHANNEL_NAME);
2017 /* Created previously, this should NOT fail. */
2018 LTTNG_ASSERT(uchan);
2019 /* Remove from the channel list of the session. */
2020 trace_ust_delete_channel(session->ust_session->domain_global.channels, uchan);
2021 trace_ust_destroy_channel(uchan);
2022 }
2023 end:
2024 return ret;
2025 }
2026
2027 static inline bool name_starts_with(const char *name, const char *prefix)
2028 {
2029 const size_t max_cmp_len = std::min(strlen(prefix), (size_t) LTTNG_SYMBOL_NAME_LEN);
2030
2031 return !strncmp(name, prefix, max_cmp_len);
2032 }
2033
2034 /* Perform userspace-specific event name validation */
2035 static int validate_ust_event_name(const char *name)
2036 {
2037 int ret = 0;
2038
2039 if (!name) {
2040 ret = -1;
2041 goto end;
2042 }
2043
2044 /*
2045 * Check name against all internal UST event component namespaces used
2046 * by the agents.
2047 */
2048 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
2049 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
2050 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
2051 ret = -1;
2052 }
2053
2054 end:
2055 return ret;
2056 }
2057
2058 /*
2059 * Internal version of cmd_enable_event() with a supplemental
2060 * "internal_event" flag which is used to enable internal events which should
2061 * be hidden from clients. Such events are used in the agent implementation to
2062 * enable the events through which all "agent" events are funeled.
2063 */
2064 static int _cmd_enable_event(struct ltt_session *session,
2065 const struct lttng_domain *domain,
2066 char *channel_name,
2067 struct lttng_event *event,
2068 char *filter_expression,
2069 struct lttng_bytecode *filter,
2070 struct lttng_event_exclusion *exclusion,
2071 int wpipe,
2072 bool internal_event)
2073 {
2074 int ret = 0, channel_created = 0;
2075 struct lttng_channel *attr = nullptr;
2076
2077 LTTNG_ASSERT(session);
2078 LTTNG_ASSERT(event);
2079 LTTNG_ASSERT(channel_name);
2080
2081 /* If we have a filter, we must have its filter expression */
2082 LTTNG_ASSERT(!(!!filter_expression ^ !!filter));
2083
2084 /* Normalize event name as a globbing pattern */
2085 strutils_normalize_star_glob_pattern(event->name);
2086
2087 /* Normalize exclusion names as globbing patterns */
2088 if (exclusion) {
2089 size_t i;
2090
2091 for (i = 0; i < exclusion->count; i++) {
2092 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2093
2094 strutils_normalize_star_glob_pattern(name);
2095 }
2096 }
2097
2098 lttng::urcu::read_lock_guard read_lock;
2099
2100 switch (domain->type) {
2101 case LTTNG_DOMAIN_KERNEL:
2102 {
2103 struct ltt_kernel_channel *kchan;
2104
2105 /*
2106 * If a non-default channel has been created in the
2107 * session, explicitely require that -c chan_name needs
2108 * to be provided.
2109 */
2110 if (session->kernel_session->has_non_default_channel && channel_name[0] == '\0') {
2111 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2112 goto error;
2113 }
2114
2115 kchan = trace_kernel_get_channel_by_name(channel_name, session->kernel_session);
2116 if (kchan == nullptr) {
2117 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL, LTTNG_BUFFER_GLOBAL);
2118 if (attr == nullptr) {
2119 ret = LTTNG_ERR_FATAL;
2120 goto error;
2121 }
2122 if (lttng_strncpy(attr->name, channel_name, sizeof(attr->name))) {
2123 ret = LTTNG_ERR_INVALID;
2124 goto error;
2125 }
2126
2127 ret = cmd_enable_channel_internal(session, domain, attr, wpipe);
2128 if (ret != LTTNG_OK) {
2129 goto error;
2130 }
2131 channel_created = 1;
2132 }
2133
2134 /* Get the newly created kernel channel pointer */
2135 kchan = trace_kernel_get_channel_by_name(channel_name, session->kernel_session);
2136 if (kchan == nullptr) {
2137 /* This sould not happen... */
2138 ret = LTTNG_ERR_FATAL;
2139 goto error;
2140 }
2141
2142 switch (event->type) {
2143 case LTTNG_EVENT_ALL:
2144 {
2145 char *filter_expression_a = nullptr;
2146 struct lttng_bytecode *filter_a = nullptr;
2147
2148 /*
2149 * We need to duplicate filter_expression and filter,
2150 * because ownership is passed to first enable
2151 * event.
2152 */
2153 if (filter_expression) {
2154 filter_expression_a = strdup(filter_expression);
2155 if (!filter_expression_a) {
2156 ret = LTTNG_ERR_FATAL;
2157 goto error;
2158 }
2159 }
2160 if (filter) {
2161 filter_a = zmalloc<lttng_bytecode>(sizeof(*filter_a) + filter->len);
2162 if (!filter_a) {
2163 free(filter_expression_a);
2164 ret = LTTNG_ERR_FATAL;
2165 goto error;
2166 }
2167 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2168 }
2169 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2170 ret = event_kernel_enable_event(kchan, event, filter_expression, filter);
2171 /* We have passed ownership */
2172 filter_expression = nullptr;
2173 filter = nullptr;
2174 if (ret != LTTNG_OK) {
2175 if (channel_created) {
2176 /* Let's not leak a useless channel. */
2177 kernel_destroy_channel(kchan);
2178 }
2179 free(filter_expression_a);
2180 free(filter_a);
2181 goto error;
2182 }
2183 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2184 ret = event_kernel_enable_event(
2185 kchan, event, filter_expression_a, filter_a);
2186 /* We have passed ownership */
2187 filter_expression_a = nullptr;
2188 filter_a = nullptr;
2189 if (ret != LTTNG_OK) {
2190 goto error;
2191 }
2192 break;
2193 }
2194 case LTTNG_EVENT_PROBE:
2195 case LTTNG_EVENT_USERSPACE_PROBE:
2196 case LTTNG_EVENT_FUNCTION:
2197 case LTTNG_EVENT_FUNCTION_ENTRY:
2198 case LTTNG_EVENT_TRACEPOINT:
2199 ret = event_kernel_enable_event(kchan, event, filter_expression, filter);
2200 /* We have passed ownership */
2201 filter_expression = nullptr;
2202 filter = nullptr;
2203 if (ret != LTTNG_OK) {
2204 if (channel_created) {
2205 /* Let's not leak a useless channel. */
2206 kernel_destroy_channel(kchan);
2207 }
2208 goto error;
2209 }
2210 break;
2211 case LTTNG_EVENT_SYSCALL:
2212 ret = event_kernel_enable_event(kchan, event, filter_expression, filter);
2213 /* We have passed ownership */
2214 filter_expression = nullptr;
2215 filter = nullptr;
2216 if (ret != LTTNG_OK) {
2217 goto error;
2218 }
2219 break;
2220 default:
2221 ret = LTTNG_ERR_UNK;
2222 goto error;
2223 }
2224
2225 kernel_wait_quiescent();
2226 break;
2227 }
2228 case LTTNG_DOMAIN_UST:
2229 {
2230 struct ltt_ust_channel *uchan;
2231 struct ltt_ust_session *usess = session->ust_session;
2232
2233 LTTNG_ASSERT(usess);
2234
2235 /*
2236 * If a non-default channel has been created in the
2237 * session, explicitely require that -c chan_name needs
2238 * to be provided.
2239 */
2240 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2241 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2242 goto error;
2243 }
2244
2245 /* Get channel from global UST domain */
2246 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels, channel_name);
2247 if (uchan == nullptr) {
2248 /* Create default channel */
2249 attr = channel_new_default_attr(LTTNG_DOMAIN_UST, usess->buffer_type);
2250 if (attr == nullptr) {
2251 ret = LTTNG_ERR_FATAL;
2252 goto error;
2253 }
2254 if (lttng_strncpy(attr->name, channel_name, sizeof(attr->name))) {
2255 ret = LTTNG_ERR_INVALID;
2256 goto error;
2257 }
2258
2259 ret = cmd_enable_channel_internal(session, domain, attr, wpipe);
2260 if (ret != LTTNG_OK) {
2261 goto error;
2262 }
2263
2264 /* Get the newly created channel reference back */
2265 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2266 channel_name);
2267 LTTNG_ASSERT(uchan);
2268 }
2269
2270 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2271 /*
2272 * Don't allow users to add UST events to channels which
2273 * are assigned to a userspace subdomain (JUL, Log4J,
2274 * Python, etc.).
2275 */
2276 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2277 goto error;
2278 }
2279
2280 if (!internal_event) {
2281 /*
2282 * Ensure the event name is not reserved for internal
2283 * use.
2284 */
2285 ret = validate_ust_event_name(event->name);
2286 if (ret) {
2287 WARN("Userspace event name %s failed validation.", event->name);
2288 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2289 goto error;
2290 }
2291 }
2292
2293 /* At this point, the session and channel exist on the tracer */
2294 ret = event_ust_enable_tracepoint(
2295 usess, uchan, event, filter_expression, filter, exclusion, internal_event);
2296 /* We have passed ownership */
2297 filter_expression = nullptr;
2298 filter = nullptr;
2299 exclusion = nullptr;
2300 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2301 goto already_enabled;
2302 } else if (ret != LTTNG_OK) {
2303 goto error;
2304 }
2305 break;
2306 }
2307 case LTTNG_DOMAIN_LOG4J:
2308 case LTTNG_DOMAIN_JUL:
2309 case LTTNG_DOMAIN_PYTHON:
2310 {
2311 const char *default_event_name, *default_chan_name;
2312 struct agent *agt;
2313 struct lttng_event uevent;
2314 struct lttng_domain tmp_dom;
2315 struct ltt_ust_session *usess = session->ust_session;
2316
2317 LTTNG_ASSERT(usess);
2318
2319 if (!agent_tracing_is_enabled()) {
2320 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2321 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2322 goto error;
2323 }
2324
2325 agt = trace_ust_find_agent(usess, domain->type);
2326 if (!agt) {
2327 agt = agent_create(domain->type);
2328 if (!agt) {
2329 ret = LTTNG_ERR_NOMEM;
2330 goto error;
2331 }
2332 agent_add(agt, usess->agents);
2333 }
2334
2335 /* Create the default tracepoint. */
2336 memset(&uevent, 0, sizeof(uevent));
2337 uevent.type = LTTNG_EVENT_TRACEPOINT;
2338 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2339 uevent.loglevel = -1;
2340 default_event_name = event_get_default_agent_ust_name(domain->type);
2341 if (!default_event_name) {
2342 ret = LTTNG_ERR_FATAL;
2343 goto error;
2344 }
2345 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2346 uevent.name[sizeof(uevent.name) - 1] = '\0';
2347
2348 /*
2349 * The domain type is changed because we are about to enable the
2350 * default channel and event for the JUL domain that are hardcoded.
2351 * This happens in the UST domain.
2352 */
2353 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2354 tmp_dom.type = LTTNG_DOMAIN_UST;
2355
2356 switch (domain->type) {
2357 case LTTNG_DOMAIN_LOG4J:
2358 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2359 break;
2360 case LTTNG_DOMAIN_JUL:
2361 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2362 break;
2363 case LTTNG_DOMAIN_PYTHON:
2364 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2365 break;
2366 default:
2367 /* The switch/case we are in makes this impossible */
2368 abort();
2369 }
2370
2371 {
2372 char *filter_expression_copy = nullptr;
2373 struct lttng_bytecode *filter_copy = nullptr;
2374
2375 if (filter) {
2376 const size_t filter_size =
2377 sizeof(struct lttng_bytecode) + filter->len;
2378
2379 filter_copy = zmalloc<lttng_bytecode>(filter_size);
2380 if (!filter_copy) {
2381 ret = LTTNG_ERR_NOMEM;
2382 goto error;
2383 }
2384 memcpy(filter_copy, filter, filter_size);
2385
2386 filter_expression_copy = strdup(filter_expression);
2387 if (!filter_expression) {
2388 ret = LTTNG_ERR_NOMEM;
2389 }
2390
2391 if (!filter_expression_copy || !filter_copy) {
2392 free(filter_expression_copy);
2393 free(filter_copy);
2394 goto error;
2395 }
2396 }
2397
2398 ret = cmd_enable_event_internal(session,
2399 &tmp_dom,
2400 (char *) default_chan_name,
2401 &uevent,
2402 filter_expression_copy,
2403 filter_copy,
2404 nullptr,
2405 wpipe);
2406 }
2407
2408 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2409 goto already_enabled;
2410 } else if (ret != LTTNG_OK) {
2411 goto error;
2412 }
2413
2414 /* The wild card * means that everything should be enabled. */
2415 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2416 ret = event_agent_enable_all(usess, agt, event, filter, filter_expression);
2417 } else {
2418 ret = event_agent_enable(usess, agt, event, filter, filter_expression);
2419 }
2420 filter = nullptr;
2421 filter_expression = nullptr;
2422 if (ret != LTTNG_OK) {
2423 goto error;
2424 }
2425
2426 break;
2427 }
2428 default:
2429 ret = LTTNG_ERR_UND;
2430 goto error;
2431 }
2432
2433 ret = LTTNG_OK;
2434
2435 already_enabled:
2436 error:
2437 free(filter_expression);
2438 free(filter);
2439 free(exclusion);
2440 channel_attr_destroy(attr);
2441 return ret;
2442 }
2443
2444 /*
2445 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2446 * We own filter, exclusion, and filter_expression.
2447 */
2448 int cmd_enable_event(struct command_ctx *cmd_ctx,
2449 struct lttng_event *event,
2450 char *filter_expression,
2451 struct lttng_event_exclusion *exclusion,
2452 struct lttng_bytecode *bytecode,
2453 int wpipe)
2454 {
2455 int ret;
2456 /*
2457 * Copied to ensure proper alignment since 'lsm' is a packed structure.
2458 */
2459 const lttng_domain command_domain = cmd_ctx->lsm.domain;
2460
2461 /*
2462 * The ownership of the following parameters is transferred to
2463 * _cmd_enable_event:
2464 *
2465 * - filter_expression,
2466 * - bytecode,
2467 * - exclusion
2468 */
2469 ret = _cmd_enable_event(cmd_ctx->session,
2470 &command_domain,
2471 cmd_ctx->lsm.u.enable.channel_name,
2472 event,
2473 filter_expression,
2474 bytecode,
2475 exclusion,
2476 wpipe,
2477 false);
2478 filter_expression = nullptr;
2479 bytecode = nullptr;
2480 exclusion = nullptr;
2481 return ret;
2482 }
2483
2484 /*
2485 * Enable an event which is internal to LTTng. An internal should
2486 * never be made visible to clients and are immune to checks such as
2487 * reserved names.
2488 */
2489 static int cmd_enable_event_internal(struct ltt_session *session,
2490 const struct lttng_domain *domain,
2491 char *channel_name,
2492 struct lttng_event *event,
2493 char *filter_expression,
2494 struct lttng_bytecode *filter,
2495 struct lttng_event_exclusion *exclusion,
2496 int wpipe)
2497 {
2498 return _cmd_enable_event(session,
2499 domain,
2500 channel_name,
2501 event,
2502 filter_expression,
2503 filter,
2504 exclusion,
2505 wpipe,
2506 true);
2507 }
2508
2509 /*
2510 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2511 */
2512 enum lttng_error_code cmd_list_tracepoints(enum lttng_domain_type domain,
2513 struct lttng_payload *reply_payload)
2514 {
2515 enum lttng_error_code ret_code;
2516 int ret;
2517 ssize_t i, nb_events = 0;
2518 struct lttng_event *events = nullptr;
2519 struct lttcomm_list_command_header reply_command_header = {};
2520 size_t reply_command_header_offset;
2521
2522 assert(reply_payload);
2523
2524 /* Reserve space for command reply header. */
2525 reply_command_header_offset = reply_payload->buffer.size;
2526 ret = lttng_dynamic_buffer_set_size(&reply_payload->buffer,
2527 reply_command_header_offset +
2528 sizeof(struct lttcomm_list_command_header));
2529 if (ret) {
2530 ret_code = LTTNG_ERR_NOMEM;
2531 goto error;
2532 }
2533
2534 switch (domain) {
2535 case LTTNG_DOMAIN_KERNEL:
2536 nb_events = kernel_list_events(&events);
2537 if (nb_events < 0) {
2538 ret_code = LTTNG_ERR_KERN_LIST_FAIL;
2539 goto error;
2540 }
2541 break;
2542 case LTTNG_DOMAIN_UST:
2543 nb_events = ust_app_list_events(&events);
2544 if (nb_events < 0) {
2545 ret_code = LTTNG_ERR_UST_LIST_FAIL;
2546 goto error;
2547 }
2548 break;
2549 case LTTNG_DOMAIN_LOG4J:
2550 case LTTNG_DOMAIN_JUL:
2551 case LTTNG_DOMAIN_PYTHON:
2552 nb_events = agent_list_events(&events, domain);
2553 if (nb_events < 0) {
2554 ret_code = LTTNG_ERR_UST_LIST_FAIL;
2555 goto error;
2556 }
2557 break;
2558 default:
2559 ret_code = LTTNG_ERR_UND;
2560 goto error;
2561 }
2562
2563 for (i = 0; i < nb_events; i++) {
2564 ret = lttng_event_serialize(
2565 &events[i], 0, nullptr, nullptr, 0, nullptr, reply_payload);
2566 if (ret) {
2567 ret_code = LTTNG_ERR_NOMEM;
2568 goto error;
2569 }
2570 }
2571
2572 if (nb_events > UINT32_MAX) {
2573 ERR("Tracepoint count would overflow the tracepoint listing command's reply");
2574 ret_code = LTTNG_ERR_OVERFLOW;
2575 goto error;
2576 }
2577
2578 /* Update command reply header. */
2579 reply_command_header.count = (uint32_t) nb_events;
2580 memcpy(reply_payload->buffer.data + reply_command_header_offset,
2581 &reply_command_header,
2582 sizeof(reply_command_header));
2583
2584 ret_code = LTTNG_OK;
2585 error:
2586 free(events);
2587 return ret_code;
2588 }
2589
2590 /*
2591 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2592 */
2593 enum lttng_error_code cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2594 struct lttng_payload *reply)
2595 {
2596 enum lttng_error_code ret_code;
2597 int ret;
2598 unsigned int i, nb_fields;
2599 struct lttng_event_field *fields = nullptr;
2600 struct lttcomm_list_command_header reply_command_header = {};
2601 size_t reply_command_header_offset;
2602
2603 assert(reply);
2604
2605 /* Reserve space for command reply header. */
2606 reply_command_header_offset = reply->buffer.size;
2607 ret = lttng_dynamic_buffer_set_size(&reply->buffer,
2608 reply_command_header_offset +
2609 sizeof(struct lttcomm_list_command_header));
2610 if (ret) {
2611 ret_code = LTTNG_ERR_NOMEM;
2612 goto error;
2613 }
2614
2615 switch (domain) {
2616 case LTTNG_DOMAIN_UST:
2617 ret = ust_app_list_event_fields(&fields);
2618 if (ret < 0) {
2619 ret_code = LTTNG_ERR_UST_LIST_FAIL;
2620 goto error;
2621 }
2622
2623 break;
2624 case LTTNG_DOMAIN_KERNEL:
2625 default: /* fall-through */
2626 ret_code = LTTNG_ERR_UND;
2627 goto error;
2628 }
2629
2630 nb_fields = ret;
2631
2632 for (i = 0; i < nb_fields; i++) {
2633 ret = lttng_event_field_serialize(&fields[i], reply);
2634 if (ret) {
2635 ret_code = LTTNG_ERR_NOMEM;
2636 goto error;
2637 }
2638 }
2639
2640 if (nb_fields > UINT32_MAX) {
2641 ERR("Tracepoint field count would overflow the tracepoint field listing command's reply");
2642 ret_code = LTTNG_ERR_OVERFLOW;
2643 goto error;
2644 }
2645
2646 /* Update command reply header. */
2647 reply_command_header.count = (uint32_t) nb_fields;
2648
2649 memcpy(reply->buffer.data + reply_command_header_offset,
2650 &reply_command_header,
2651 sizeof(reply_command_header));
2652
2653 ret_code = LTTNG_OK;
2654
2655 error:
2656 free(fields);
2657 return ret_code;
2658 }
2659
2660 enum lttng_error_code cmd_list_syscalls(struct lttng_payload *reply_payload)
2661 {
2662 enum lttng_error_code ret_code;
2663 ssize_t nb_events, i;
2664 int ret;
2665 struct lttng_event *events = nullptr;
2666 struct lttcomm_list_command_header reply_command_header = {};
2667 size_t reply_command_header_offset;
2668
2669 assert(reply_payload);
2670
2671 /* Reserve space for command reply header. */
2672 reply_command_header_offset = reply_payload->buffer.size;
2673 ret = lttng_dynamic_buffer_set_size(&reply_payload->buffer,
2674 reply_command_header_offset +
2675 sizeof(struct lttcomm_list_command_header));
2676 if (ret) {
2677 ret_code = LTTNG_ERR_NOMEM;
2678 goto end;
2679 }
2680
2681 nb_events = syscall_table_list(&events);
2682 if (nb_events < 0) {
2683 ret_code = (enum lttng_error_code) - nb_events;
2684 goto end;
2685 }
2686
2687 for (i = 0; i < nb_events; i++) {
2688 ret = lttng_event_serialize(
2689 &events[i], 0, nullptr, nullptr, 0, nullptr, reply_payload);
2690 if (ret) {
2691 ret_code = LTTNG_ERR_NOMEM;
2692 goto end;
2693 }
2694 }
2695
2696 if (nb_events > UINT32_MAX) {
2697 ERR("Syscall count would overflow the syscall listing command's reply");
2698 ret_code = LTTNG_ERR_OVERFLOW;
2699 goto end;
2700 }
2701
2702 /* Update command reply header. */
2703 reply_command_header.count = (uint32_t) nb_events;
2704 memcpy(reply_payload->buffer.data + reply_command_header_offset,
2705 &reply_command_header,
2706 sizeof(reply_command_header));
2707
2708 ret_code = LTTNG_OK;
2709 end:
2710 free(events);
2711 return ret_code;
2712 }
2713
2714 /*
2715 * Command LTTNG_START_TRACE processed by the client thread.
2716 *
2717 * Called with session mutex held.
2718 */
2719 int cmd_start_trace(struct ltt_session *session)
2720 {
2721 enum lttng_error_code ret;
2722 unsigned long nb_chan = 0;
2723 struct ltt_kernel_session *ksession;
2724 struct ltt_ust_session *usess;
2725 const bool session_rotated_after_last_stop = session->rotated_after_last_stop;
2726 const bool session_cleared_after_last_stop = session->cleared_after_last_stop;
2727
2728 LTTNG_ASSERT(session);
2729
2730 /* Ease our life a bit ;) */
2731 ksession = session->kernel_session;
2732 usess = session->ust_session;
2733
2734 /* Is the session already started? */
2735 if (session->active) {
2736 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2737 /* Perform nothing */
2738 goto end;
2739 }
2740
2741 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2742 !session->current_trace_chunk) {
2743 /*
2744 * A rotation was launched while the session was stopped and
2745 * it has not been completed yet. It is not possible to start
2746 * the session since starting the session here would require a
2747 * rotation from "NULL" to a new trace chunk. That rotation
2748 * would overlap with the ongoing rotation, which is not
2749 * supported.
2750 */
2751 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2752 session->name);
2753 ret = LTTNG_ERR_ROTATION_PENDING;
2754 goto error;
2755 }
2756
2757 /*
2758 * Starting a session without channel is useless since after that it's not
2759 * possible to enable channel thus inform the client.
2760 */
2761 if (usess && usess->domain_global.channels) {
2762 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2763 }
2764 if (ksession) {
2765 nb_chan += ksession->channel_count;
2766 }
2767 if (!nb_chan) {
2768 ret = LTTNG_ERR_NO_CHANNEL;
2769 goto error;
2770 }
2771
2772 session->active = true;
2773 session->rotated_after_last_stop = false;
2774 session->cleared_after_last_stop = false;
2775 if (session->output_traces && !session->current_trace_chunk) {
2776 if (!session->has_been_started) {
2777 struct lttng_trace_chunk *trace_chunk;
2778
2779 DBG("Creating initial trace chunk of session \"%s\"", session->name);
2780 trace_chunk =
2781 session_create_new_trace_chunk(session, nullptr, nullptr, nullptr);
2782 if (!trace_chunk) {
2783 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2784 goto error;
2785 }
2786 LTTNG_ASSERT(!session->current_trace_chunk);
2787 ret = (lttng_error_code) session_set_trace_chunk(
2788 session, trace_chunk, nullptr);
2789 lttng_trace_chunk_put(trace_chunk);
2790 if (ret) {
2791 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2792 goto error;
2793 }
2794 } else {
2795 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2796 session->name);
2797 /*
2798 * Rotate existing streams into the new chunk.
2799 * This is a "quiet" rotation has no client has
2800 * explicitly requested this operation.
2801 *
2802 * There is also no need to wait for the rotation
2803 * to complete as it will happen immediately. No data
2804 * was produced as the session was stopped, so the
2805 * rotation should happen on reception of the command.
2806 */
2807 ret = (lttng_error_code) cmd_rotate_session(
2808 session, nullptr, true, LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
2809 if (ret != LTTNG_OK) {
2810 goto error;
2811 }
2812 }
2813 }
2814
2815 /* Kernel tracing */
2816 if (ksession != nullptr) {
2817 DBG("Start kernel tracing session %s", session->name);
2818 ret = (lttng_error_code) start_kernel_session(ksession);
2819 if (ret != LTTNG_OK) {
2820 goto error;
2821 }
2822 }
2823
2824 /* Flag session that trace should start automatically */
2825 if (usess) {
2826 int int_ret = ust_app_start_trace_all(usess);
2827
2828 if (int_ret < 0) {
2829 ret = LTTNG_ERR_UST_START_FAIL;
2830 goto error;
2831 }
2832 }
2833
2834 /*
2835 * Open a packet in every stream of the session to ensure that viewers
2836 * can correctly identify the boundaries of the periods during which
2837 * tracing was active for this session.
2838 */
2839 ret = session_open_packets(session);
2840 if (ret != LTTNG_OK) {
2841 goto error;
2842 }
2843
2844 /*
2845 * Clear the flag that indicates that a rotation was done while the
2846 * session was stopped.
2847 */
2848 session->rotated_after_last_stop = false;
2849
2850 if (session->rotate_timer_period && !session->rotation_schedule_timer_enabled) {
2851 int int_ret = timer_session_rotation_schedule_timer_start(
2852 session, session->rotate_timer_period);
2853
2854 if (int_ret < 0) {
2855 ERR("Failed to enable rotate timer");
2856 ret = LTTNG_ERR_UNK;
2857 goto error;
2858 }
2859 }
2860
2861 ret = LTTNG_OK;
2862
2863 error:
2864 if (ret == LTTNG_OK) {
2865 /* Flag this after a successful start. */
2866 session->has_been_started = true;
2867 } else {
2868 session->active = false;
2869 /* Restore initial state on error. */
2870 session->rotated_after_last_stop = session_rotated_after_last_stop;
2871 session->cleared_after_last_stop = session_cleared_after_last_stop;
2872 }
2873 end:
2874 return ret;
2875 }
2876
2877 /*
2878 * Command LTTNG_STOP_TRACE processed by the client thread.
2879 */
2880 int cmd_stop_trace(struct ltt_session *session)
2881 {
2882 int ret;
2883 struct ltt_kernel_session *ksession;
2884 struct ltt_ust_session *usess;
2885
2886 LTTNG_ASSERT(session);
2887
2888 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2889 /* Short cut */
2890 ksession = session->kernel_session;
2891 usess = session->ust_session;
2892
2893 /* Session is not active. Skip everything and inform the client. */
2894 if (!session->active) {
2895 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2896 goto error;
2897 }
2898
2899 ret = stop_kernel_session(ksession);
2900 if (ret != LTTNG_OK) {
2901 goto error;
2902 }
2903
2904 if (usess && usess->active) {
2905 ret = ust_app_stop_trace_all(usess);
2906 if (ret < 0) {
2907 ret = LTTNG_ERR_UST_STOP_FAIL;
2908 goto error;
2909 }
2910 }
2911
2912 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2913 /* Flag inactive after a successful stop. */
2914 session->active = false;
2915 ret = LTTNG_OK;
2916
2917 error:
2918 return ret;
2919 }
2920
2921 /*
2922 * Set the base_path of the session only if subdir of a control uris is set.
2923 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2924 */
2925 static int
2926 set_session_base_path_from_uris(struct ltt_session *session, size_t nb_uri, struct lttng_uri *uris)
2927 {
2928 int ret;
2929 size_t i;
2930
2931 for (i = 0; i < nb_uri; i++) {
2932 if (uris[i].stype != LTTNG_STREAM_CONTROL || uris[i].subdir[0] == '\0') {
2933 /* Not interested in these URIs */
2934 continue;
2935 }
2936
2937 if (session->base_path != nullptr) {
2938 free(session->base_path);
2939 session->base_path = nullptr;
2940 }
2941
2942 /* Set session base_path */
2943 session->base_path = strdup(uris[i].subdir);
2944 if (!session->base_path) {
2945 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2946 uris[i].subdir,
2947 session->name);
2948 ret = LTTNG_ERR_NOMEM;
2949 goto error;
2950 }
2951 DBG2("Setting base path \"%s\" for session \"%s\"",
2952 session->base_path,
2953 session->name);
2954 }
2955 ret = LTTNG_OK;
2956 error:
2957 return ret;
2958 }
2959
2960 /*
2961 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2962 */
2963 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri, struct lttng_uri *uris)
2964 {
2965 int ret, i;
2966 struct ltt_kernel_session *ksess = session->kernel_session;
2967 struct ltt_ust_session *usess = session->ust_session;
2968
2969 LTTNG_ASSERT(session);
2970 LTTNG_ASSERT(uris);
2971 LTTNG_ASSERT(nb_uri > 0);
2972
2973 /* Can't set consumer URI if the session is active. */
2974 if (session->active) {
2975 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2976 goto error;
2977 }
2978
2979 /*
2980 * Set the session base path if any. This is done inside
2981 * cmd_set_consumer_uri to preserve backward compatibility of the
2982 * previous session creation api vs the session descriptor api.
2983 */
2984 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2985 if (ret != LTTNG_OK) {
2986 goto error;
2987 }
2988
2989 /* Set the "global" consumer URIs */
2990 for (i = 0; i < nb_uri; i++) {
2991 ret = add_uri_to_consumer(session, session->consumer, &uris[i], LTTNG_DOMAIN_NONE);
2992 if (ret != LTTNG_OK) {
2993 goto error;
2994 }
2995 }
2996
2997 /* Set UST session URIs */
2998 if (session->ust_session) {
2999 for (i = 0; i < nb_uri; i++) {
3000 ret = add_uri_to_consumer(session,
3001 session->ust_session->consumer,
3002 &uris[i],
3003 LTTNG_DOMAIN_UST);
3004 if (ret != LTTNG_OK) {
3005 goto error;
3006 }
3007 }
3008 }
3009
3010 /* Set kernel session URIs */
3011 if (session->kernel_session) {
3012 for (i = 0; i < nb_uri; i++) {
3013 ret = add_uri_to_consumer(session,
3014 session->kernel_session->consumer,
3015 &uris[i],
3016 LTTNG_DOMAIN_KERNEL);
3017 if (ret != LTTNG_OK) {
3018 goto error;
3019 }
3020 }
3021 }
3022
3023 /*
3024 * Make sure to set the session in output mode after we set URI since a
3025 * session can be created without URL (thus flagged in no output mode).
3026 */
3027 session->output_traces = 1;
3028 if (ksess) {
3029 ksess->output_traces = 1;
3030 }
3031
3032 if (usess) {
3033 usess->output_traces = 1;
3034 }
3035
3036 /* All good! */
3037 ret = LTTNG_OK;
3038
3039 error:
3040 return ret;
3041 }
3042
3043 static enum lttng_error_code
3044 set_session_output_from_descriptor(struct ltt_session *session,
3045 const struct lttng_session_descriptor *descriptor)
3046 {
3047 int ret;
3048 enum lttng_error_code ret_code = LTTNG_OK;
3049 enum lttng_session_descriptor_type session_type =
3050 lttng_session_descriptor_get_type(descriptor);
3051 enum lttng_session_descriptor_output_type output_type =
3052 lttng_session_descriptor_get_output_type(descriptor);
3053 struct lttng_uri uris[2] = {};
3054 size_t uri_count = 0;
3055
3056 switch (output_type) {
3057 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
3058 goto end;
3059 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
3060 lttng_session_descriptor_get_local_output_uri(descriptor, &uris[0]);
3061 uri_count = 1;
3062 break;
3063 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
3064 lttng_session_descriptor_get_network_output_uris(descriptor, &uris[0], &uris[1]);
3065 uri_count = 2;
3066 break;
3067 default:
3068 ret_code = LTTNG_ERR_INVALID;
3069 goto end;
3070 }
3071
3072 switch (session_type) {
3073 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3074 {
3075 struct snapshot_output *new_output = nullptr;
3076
3077 new_output = snapshot_output_alloc();
3078 if (!new_output) {
3079 ret_code = LTTNG_ERR_NOMEM;
3080 goto end;
3081 }
3082
3083 ret = snapshot_output_init_with_uri(session,
3084 DEFAULT_SNAPSHOT_MAX_SIZE,
3085 nullptr,
3086 uris,
3087 uri_count,
3088 session->consumer,
3089 new_output,
3090 &session->snapshot);
3091 if (ret < 0) {
3092 ret_code = (ret == -ENOMEM) ? LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
3093 snapshot_output_destroy(new_output);
3094 goto end;
3095 }
3096 snapshot_add_output(&session->snapshot, new_output);
3097 break;
3098 }
3099 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
3100 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3101 {
3102 ret_code = (lttng_error_code) cmd_set_consumer_uri(session, uri_count, uris);
3103 break;
3104 }
3105 default:
3106 ret_code = LTTNG_ERR_INVALID;
3107 goto end;
3108 }
3109 end:
3110 return ret_code;
3111 }
3112
3113 static enum lttng_error_code
3114 cmd_create_session_from_descriptor(struct lttng_session_descriptor *descriptor,
3115 const lttng_sock_cred *creds,
3116 const char *home_path)
3117 {
3118 int ret;
3119 enum lttng_error_code ret_code;
3120 const char *session_name;
3121 struct ltt_session *new_session = nullptr;
3122 enum lttng_session_descriptor_status descriptor_status;
3123
3124 session_lock_list();
3125 if (home_path) {
3126 if (*home_path != '/') {
3127 ERR("Home path provided by client is not absolute");
3128 ret_code = LTTNG_ERR_INVALID;
3129 goto end;
3130 }
3131 }
3132
3133 descriptor_status = lttng_session_descriptor_get_session_name(descriptor, &session_name);
3134 switch (descriptor_status) {
3135 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3136 break;
3137 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3138 session_name = nullptr;
3139 break;
3140 default:
3141 ret_code = LTTNG_ERR_INVALID;
3142 goto end;
3143 }
3144
3145 ret_code = session_create(session_name, creds->uid, creds->gid, &new_session);
3146 if (ret_code != LTTNG_OK) {
3147 goto end;
3148 }
3149
3150 ret_code = notification_thread_command_add_session(the_notification_thread_handle,
3151 new_session->id,
3152 new_session->name,
3153 new_session->uid,
3154 new_session->gid);
3155 if (ret_code != LTTNG_OK) {
3156 goto end;
3157 }
3158
3159 /* Announce the session's destruction to the notification thread when it is destroyed. */
3160 ret = session_add_destroy_notifier(
3161 new_session,
3162 [](const struct ltt_session *session, void *user_data __attribute__((unused))) {
3163 (void) notification_thread_command_remove_session(
3164 the_notification_thread_handle, session->id);
3165 },
3166 nullptr);
3167 if (ret) {
3168 PERROR("Failed to add notification thread command to session's destroy notifiers: session name = %s",
3169 new_session->name);
3170 ret = LTTNG_ERR_NOMEM;
3171 goto end;
3172 }
3173
3174 if (!session_name) {
3175 ret = lttng_session_descriptor_set_session_name(descriptor, new_session->name);
3176 if (ret) {
3177 ret_code = LTTNG_ERR_SESSION_FAIL;
3178 goto end;
3179 }
3180 }
3181
3182 if (!lttng_session_descriptor_is_output_destination_initialized(descriptor)) {
3183 /*
3184 * Only include the session's creation time in the output
3185 * destination if the name of the session itself was
3186 * not auto-generated.
3187 */
3188 ret_code = lttng_session_descriptor_set_default_output(
3189 descriptor,
3190 session_name ? &new_session->creation_time : nullptr,
3191 home_path);
3192 if (ret_code != LTTNG_OK) {
3193 goto end;
3194 }
3195 } else {
3196 new_session->has_user_specified_directory =
3197 lttng_session_descriptor_has_output_directory(descriptor);
3198 }
3199
3200 switch (lttng_session_descriptor_get_type(descriptor)) {
3201 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3202 new_session->snapshot_mode = 1;
3203 break;
3204 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3205 new_session->live_timer =
3206 lttng_session_descriptor_live_get_timer_interval(descriptor);
3207 break;
3208 default:
3209 break;
3210 }
3211
3212 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3213 if (ret_code != LTTNG_OK) {
3214 goto end;
3215 }
3216 new_session->consumer->enabled = true;
3217 ret_code = LTTNG_OK;
3218 end:
3219 /* Release reference provided by the session_create function. */
3220 session_put(new_session);
3221 if (ret_code != LTTNG_OK && new_session) {
3222 /* Release the global reference on error. */
3223 session_destroy(new_session);
3224 }
3225 session_unlock_list();
3226 return ret_code;
3227 }
3228
3229 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx,
3230 int sock,
3231 struct lttng_session_descriptor **return_descriptor)
3232 {
3233 int ret;
3234 size_t payload_size;
3235 struct lttng_dynamic_buffer payload;
3236 struct lttng_buffer_view home_dir_view;
3237 struct lttng_buffer_view session_descriptor_view;
3238 struct lttng_session_descriptor *session_descriptor = nullptr;
3239 enum lttng_error_code ret_code;
3240
3241 lttng_dynamic_buffer_init(&payload);
3242 if (cmd_ctx->lsm.u.create_session.home_dir_size >= LTTNG_PATH_MAX) {
3243 ret_code = LTTNG_ERR_INVALID;
3244 goto error;
3245 }
3246 if (cmd_ctx->lsm.u.create_session.session_descriptor_size >
3247 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3248 ret_code = LTTNG_ERR_INVALID;
3249 goto error;
3250 }
3251
3252 payload_size = cmd_ctx->lsm.u.create_session.home_dir_size +
3253 cmd_ctx->lsm.u.create_session.session_descriptor_size;
3254 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3255 if (ret) {
3256 ret_code = LTTNG_ERR_NOMEM;
3257 goto error;
3258 }
3259
3260 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3261 if (ret <= 0) {
3262 ERR("Reception of session descriptor failed, aborting.");
3263 ret_code = LTTNG_ERR_SESSION_FAIL;
3264 goto error;
3265 }
3266
3267 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3268 &payload, 0, cmd_ctx->lsm.u.create_session.home_dir_size);
3269 if (cmd_ctx->lsm.u.create_session.home_dir_size > 0 &&
3270 !lttng_buffer_view_is_valid(&home_dir_view)) {
3271 ERR("Invalid payload in \"create session\" command: buffer too short to contain home directory");
3272 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
3273 goto error;
3274 }
3275
3276 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3277 &payload,
3278 cmd_ctx->lsm.u.create_session.home_dir_size,
3279 cmd_ctx->lsm.u.create_session.session_descriptor_size);
3280 if (!lttng_buffer_view_is_valid(&session_descriptor_view)) {
3281 ERR("Invalid payload in \"create session\" command: buffer too short to contain session descriptor");
3282 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
3283 goto error;
3284 }
3285
3286 ret = lttng_session_descriptor_create_from_buffer(&session_descriptor_view,
3287 &session_descriptor);
3288 if (ret < 0) {
3289 ERR("Failed to create session descriptor from payload of \"create session\" command");
3290 ret_code = LTTNG_ERR_INVALID;
3291 goto error;
3292 }
3293
3294 /*
3295 * Sets the descriptor's auto-generated properties (name, output) if
3296 * needed.
3297 */
3298 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3299 &cmd_ctx->creds,
3300 home_dir_view.size ? home_dir_view.data :
3301 nullptr);
3302 if (ret_code != LTTNG_OK) {
3303 goto error;
3304 }
3305
3306 ret_code = LTTNG_OK;
3307 *return_descriptor = session_descriptor;
3308 session_descriptor = nullptr;
3309 error:
3310 lttng_dynamic_buffer_reset(&payload);
3311 lttng_session_descriptor_destroy(session_descriptor);
3312 return ret_code;
3313 }
3314
3315 static void cmd_destroy_session_reply(const struct ltt_session *session, void *_reply_context)
3316 {
3317 int ret;
3318 ssize_t comm_ret;
3319 const struct cmd_destroy_session_reply_context *reply_context =
3320 (cmd_destroy_session_reply_context *) _reply_context;
3321 struct lttng_dynamic_buffer payload;
3322 struct lttcomm_session_destroy_command_header cmd_header;
3323 struct lttng_trace_archive_location *location = nullptr;
3324 struct lttcomm_lttng_msg llm = {
3325 .cmd_type = LTTCOMM_SESSIOND_COMMAND_DESTROY_SESSION,
3326 .ret_code = reply_context->destruction_status,
3327 .pid = UINT32_MAX,
3328 .cmd_header_size = sizeof(struct lttcomm_session_destroy_command_header),
3329 .data_size = 0,
3330 .fd_count = 0,
3331 };
3332 size_t payload_size_before_location;
3333
3334 lttng_dynamic_buffer_init(&payload);
3335
3336 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3337 if (ret) {
3338 ERR("Failed to append session destruction message");
3339 goto error;
3340 }
3341
3342 cmd_header.rotation_state = (int32_t) (reply_context->implicit_rotation_on_destroy ?
3343 session->rotation_state :
3344 LTTNG_ROTATION_STATE_NO_ROTATION);
3345 ret = lttng_dynamic_buffer_append(&payload, &cmd_header, sizeof(cmd_header));
3346 if (ret) {
3347 ERR("Failed to append session destruction command header");
3348 goto error;
3349 }
3350
3351 if (!reply_context->implicit_rotation_on_destroy) {
3352 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3353 session->name);
3354 goto send_reply;
3355 }
3356 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3357 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3358 session->name);
3359 goto send_reply;
3360 }
3361
3362 location = session_get_trace_archive_location(session);
3363 if (!location) {
3364 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3365 session->name);
3366 goto error;
3367 }
3368
3369 payload_size_before_location = payload.size;
3370 comm_ret = lttng_trace_archive_location_serialize(location, &payload);
3371 lttng_trace_archive_location_put(location);
3372 if (comm_ret < 0) {
3373 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3374 session->name);
3375 goto error;
3376 }
3377 /* Update the message to indicate the location's length. */
3378 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3379 payload.size - payload_size_before_location;
3380 send_reply:
3381 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd, payload.data, payload.size);
3382 if (comm_ret != (ssize_t) payload.size) {
3383 ERR("Failed to send result of the destruction of session \"%s\" to client",
3384 session->name);
3385 }
3386 error:
3387 ret = close(reply_context->reply_sock_fd);
3388 if (ret) {
3389 PERROR("Failed to close client socket in deferred session destroy reply");
3390 }
3391 lttng_dynamic_buffer_reset(&payload);
3392 free(_reply_context);
3393 }
3394
3395 /*
3396 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3397 *
3398 * Called with session lock held.
3399 */
3400 int cmd_destroy_session(struct ltt_session *session, int *sock_fd)
3401 {
3402 int ret;
3403 enum lttng_error_code destruction_last_error = LTTNG_OK;
3404 struct cmd_destroy_session_reply_context *reply_context = nullptr;
3405
3406 if (sock_fd) {
3407 reply_context = zmalloc<cmd_destroy_session_reply_context>();
3408 if (!reply_context) {
3409 ret = LTTNG_ERR_NOMEM;
3410 goto end;
3411 }
3412
3413 reply_context->reply_sock_fd = *sock_fd;
3414 }
3415
3416 /* Safety net */
3417 LTTNG_ASSERT(session);
3418
3419 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name, session->id);
3420 if (session->active) {
3421 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3422 session->name);
3423 ret = cmd_stop_trace(session);
3424 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3425 /* Carry on with the destruction of the session. */
3426 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3427 session->name,
3428 lttng_strerror(-ret));
3429 destruction_last_error = (lttng_error_code) ret;
3430 }
3431 }
3432
3433 if (session->rotation_schedule_timer_enabled) {
3434 if (timer_session_rotation_schedule_timer_stop(session)) {
3435 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3436 session->name);
3437 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3438 }
3439 }
3440
3441 if (session->rotate_size) {
3442 try {
3443 the_rotation_thread_handle->unsubscribe_session_consumed_size_rotation(
3444 *session);
3445 } catch (const std::exception& e) {
3446 /* Continue the destruction of the session anyway. */
3447 ERR("Failed to unsubscribe rotation thread notification channel from consumed size condition during session destruction: %s",
3448 e.what());
3449 }
3450
3451 session->rotate_size = 0;
3452 }
3453
3454 if (session->rotated && session->current_trace_chunk && session->output_traces) {
3455 /*
3456 * Perform a last rotation on destruction if rotations have
3457 * occurred during the session's lifetime.
3458 */
3459 ret = cmd_rotate_session(
3460 session, nullptr, false, LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3461 if (ret != LTTNG_OK) {
3462 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3463 session->name,
3464 lttng_strerror(-ret));
3465 destruction_last_error = (lttng_error_code) -ret;
3466 }
3467 if (reply_context) {
3468 reply_context->implicit_rotation_on_destroy = true;
3469 }
3470 } else if (session->has_been_started && session->current_trace_chunk) {
3471 /*
3472 * The user has not triggered a session rotation. However, to
3473 * ensure all data has been consumed, the session is rotated
3474 * to a 'null' trace chunk before it is destroyed.
3475 *
3476 * This is a "quiet" rotation meaning that no notification is
3477 * emitted and no renaming of the current trace chunk takes
3478 * place.
3479 */
3480 ret = cmd_rotate_session(
3481 session, nullptr, true, LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3482 /*
3483 * Rotation operations may not be supported by the kernel
3484 * tracer. Hence, do not consider this implicit rotation as
3485 * a session destruction error. The library has already stopped
3486 * the session and waited for pending data; there is nothing
3487 * left to do but complete the destruction of the session.
3488 */
3489 if (ret != LTTNG_OK && ret != -LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL) {
3490 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3491 session->name,
3492 lttng_strerror(ret));
3493 destruction_last_error = (lttng_error_code) -ret;
3494 }
3495 }
3496
3497 if (session->shm_path[0]) {
3498 /*
3499 * When a session is created with an explicit shm_path,
3500 * the consumer daemon will create its shared memory files
3501 * at that location and will *not* unlink them. This is normal
3502 * as the intention of that feature is to make it possible
3503 * to retrieve the content of those files should a crash occur.
3504 *
3505 * To ensure the content of those files can be used, the
3506 * sessiond daemon will replicate the content of the metadata
3507 * cache in a metadata file.
3508 *
3509 * On clean-up, it is expected that the consumer daemon will
3510 * unlink the shared memory files and that the session daemon
3511 * will unlink the metadata file. Then, the session's directory
3512 * in the shm path can be removed.
3513 *
3514 * Unfortunately, a flaw in the design of the sessiond's and
3515 * consumerd's tear down of channels makes it impossible to
3516 * determine when the sessiond _and_ the consumerd have both
3517 * destroyed their representation of a channel. For one, the
3518 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3519 * callbacks in both daemons.
3520 *
3521 * However, it is also impossible for the sessiond to know when
3522 * the consumer daemon is done destroying its channel(s) since
3523 * it occurs as a reaction to the closing of the channel's file
3524 * descriptor. There is no resulting communication initiated
3525 * from the consumerd to the sessiond to confirm that the
3526 * operation is completed (and was successful).
3527 *
3528 * Until this is all fixed, the session daemon checks for the
3529 * removal of the session's shm path which makes it possible
3530 * to safely advertise a session as having been destroyed.
3531 *
3532 * Prior to this fix, it was not possible to reliably save
3533 * a session making use of the --shm-path option, destroy it,
3534 * and load it again. This is because the creation of the
3535 * session would fail upon seeing the session's shm path
3536 * already in existence.
3537 *
3538 * Note that none of the error paths in the check for the
3539 * directory's existence return an error. This is normal
3540 * as there isn't much that can be done. The session will
3541 * be destroyed properly, except that we can't offer the
3542 * guarantee that the same session can be re-created.
3543 */
3544 current_completion_handler = &destroy_completion_handler.handler;
3545 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3546 session->shm_path,
3547 sizeof(destroy_completion_handler.shm_path));
3548 LTTNG_ASSERT(!ret);
3549 }
3550
3551 /*
3552 * The session is destroyed. However, note that the command context
3553 * still holds a reference to the session, thus delaying its destruction
3554 * _at least_ up to the point when that reference is released.
3555 */
3556 session_destroy(session);
3557 if (reply_context) {
3558 reply_context->destruction_status = destruction_last_error;
3559 ret = session_add_destroy_notifier(
3560 session, cmd_destroy_session_reply, (void *) reply_context);
3561 if (ret) {
3562 ret = LTTNG_ERR_FATAL;
3563 goto end;
3564 } else {
3565 *sock_fd = -1;
3566 }
3567 }
3568 ret = LTTNG_OK;
3569 end:
3570 return ret;
3571 }
3572
3573 /*
3574 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3575 */
3576 int cmd_register_consumer(struct ltt_session *session,
3577 enum lttng_domain_type domain,
3578 const char *sock_path,
3579 struct consumer_data *cdata)
3580 {
3581 int ret, sock;
3582 struct consumer_socket *socket = nullptr;
3583
3584 LTTNG_ASSERT(session);
3585 LTTNG_ASSERT(cdata);
3586 LTTNG_ASSERT(sock_path);
3587
3588 switch (domain) {
3589 case LTTNG_DOMAIN_KERNEL:
3590 {
3591 struct ltt_kernel_session *ksess = session->kernel_session;
3592
3593 LTTNG_ASSERT(ksess);
3594
3595 /* Can't register a consumer if there is already one */
3596 if (ksess->consumer_fds_sent != 0) {
3597 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3598 goto error;
3599 }
3600
3601 sock = lttcomm_connect_unix_sock(sock_path);
3602 if (sock < 0) {
3603 ret = LTTNG_ERR_CONNECT_FAIL;
3604 goto error;
3605 }
3606 cdata->cmd_sock = sock;
3607
3608 socket = consumer_allocate_socket(&cdata->cmd_sock);
3609 if (socket == nullptr) {
3610 ret = close(sock);
3611 if (ret < 0) {
3612 PERROR("close register consumer");
3613 }
3614 cdata->cmd_sock = -1;
3615 ret = LTTNG_ERR_FATAL;
3616 goto error;
3617 }
3618
3619 socket->lock = zmalloc<pthread_mutex_t>();
3620 if (socket->lock == nullptr) {
3621 PERROR("zmalloc pthread mutex");
3622 ret = LTTNG_ERR_FATAL;
3623 goto error;
3624 }
3625
3626 pthread_mutex_init(socket->lock, nullptr);
3627 socket->registered = 1;
3628
3629 lttng::urcu::read_lock_guard read_lock;
3630 consumer_add_socket(socket, ksess->consumer);
3631
3632 pthread_mutex_lock(&cdata->pid_mutex);
3633 cdata->pid = -1;
3634 pthread_mutex_unlock(&cdata->pid_mutex);
3635
3636 break;
3637 }
3638 default:
3639 /* TODO: Userspace tracing */
3640 ret = LTTNG_ERR_UND;
3641 goto error;
3642 }
3643
3644 return LTTNG_OK;
3645
3646 error:
3647 if (socket) {
3648 consumer_destroy_socket(socket);
3649 }
3650 return ret;
3651 }
3652
3653 /*
3654 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3655 */
3656 ssize_t cmd_list_domains(struct ltt_session *session, struct lttng_domain **domains)
3657 {
3658 int ret, index = 0;
3659 ssize_t nb_dom = 0;
3660 struct agent *agt;
3661 struct lttng_ht_iter iter;
3662
3663 if (session->kernel_session != nullptr) {
3664 DBG3("Listing domains found kernel domain");
3665 nb_dom++;
3666 }
3667
3668 if (session->ust_session != nullptr) {
3669 DBG3("Listing domains found UST global domain");
3670 nb_dom++;
3671
3672 lttng::urcu::read_lock_guard read_lock;
3673
3674 cds_lfht_for_each_entry (
3675 session->ust_session->agents->ht, &iter.iter, agt, node.node) {
3676 if (agt->being_used) {
3677 nb_dom++;
3678 }
3679 }
3680 }
3681
3682 if (!nb_dom) {
3683 goto end;
3684 }
3685
3686 *domains = calloc<lttng_domain>(nb_dom);
3687 if (*domains == nullptr) {
3688 ret = LTTNG_ERR_FATAL;
3689 goto error;
3690 }
3691
3692 if (session->kernel_session != nullptr) {
3693 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3694
3695 /* Kernel session buffer type is always GLOBAL */
3696 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3697
3698 index++;
3699 }
3700
3701 if (session->ust_session != nullptr) {
3702 (*domains)[index].type = LTTNG_DOMAIN_UST;
3703 (*domains)[index].buf_type = session->ust_session->buffer_type;
3704 index++;
3705
3706 {
3707 lttng::urcu::read_lock_guard read_lock;
3708
3709 cds_lfht_for_each_entry (
3710 session->ust_session->agents->ht, &iter.iter, agt, node.node) {
3711 if (agt->being_used) {
3712 (*domains)[index].type = agt->domain;
3713 (*domains)[index].buf_type =
3714 session->ust_session->buffer_type;
3715 index++;
3716 }
3717 }
3718 }
3719 }
3720 end:
3721 return nb_dom;
3722
3723 error:
3724 /* Return negative value to differentiate return code */
3725 return -ret;
3726 }
3727
3728 /*
3729 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3730 */
3731 enum lttng_error_code cmd_list_channels(enum lttng_domain_type domain,
3732 struct ltt_session *session,
3733 struct lttng_payload *payload)
3734 {
3735 int ret = 0;
3736 unsigned int i = 0;
3737 struct lttcomm_list_command_header cmd_header = {};
3738 size_t cmd_header_offset;
3739 enum lttng_error_code ret_code;
3740
3741 assert(session);
3742 assert(payload);
3743
3744 DBG("Listing channels for session %s", session->name);
3745
3746 cmd_header_offset = payload->buffer.size;
3747
3748 /* Reserve space for command reply header. */
3749 ret = lttng_dynamic_buffer_set_size(&payload->buffer,
3750 cmd_header_offset + sizeof(cmd_header));
3751 if (ret) {
3752 ret_code = LTTNG_ERR_NOMEM;
3753 goto end;
3754 }
3755
3756 switch (domain) {
3757 case LTTNG_DOMAIN_KERNEL:
3758 {
3759 /* Kernel channels */
3760 struct ltt_kernel_channel *kchan;
3761 if (session->kernel_session != nullptr) {
3762 cds_list_for_each_entry (
3763 kchan, &session->kernel_session->channel_list.head, list) {
3764 uint64_t discarded_events, lost_packets;
3765 struct lttng_channel_extended *extended;
3766
3767 extended = (struct lttng_channel_extended *)
3768 kchan->channel->attr.extended.ptr;
3769
3770 ret = get_kernel_runtime_stats(
3771 session, kchan, &discarded_events, &lost_packets);
3772 if (ret < 0) {
3773 ret_code = LTTNG_ERR_UNK;
3774 goto end;
3775 }
3776
3777 /*
3778 * Update the discarded_events and lost_packets
3779 * count for the channel
3780 */
3781 extended->discarded_events = discarded_events;
3782 extended->lost_packets = lost_packets;
3783
3784 ret = lttng_channel_serialize(kchan->channel, &payload->buffer);
3785 if (ret) {
3786 ERR("Failed to serialize lttng_channel: channel name = '%s'",
3787 kchan->channel->name);
3788 ret_code = LTTNG_ERR_UNK;
3789 goto end;
3790 }
3791
3792 i++;
3793 }
3794 }
3795 break;
3796 }
3797 case LTTNG_DOMAIN_UST:
3798 {
3799 struct lttng_ht_iter iter;
3800 struct ltt_ust_channel *uchan;
3801
3802 {
3803 lttng::urcu::read_lock_guard read_lock;
3804
3805 cds_lfht_for_each_entry (session->ust_session->domain_global.channels->ht,
3806 &iter.iter,
3807 uchan,
3808 node.node) {
3809 uint64_t discarded_events = 0, lost_packets = 0;
3810 struct lttng_channel *channel = nullptr;
3811 struct lttng_channel_extended *extended;
3812
3813 channel = trace_ust_channel_to_lttng_channel(uchan);
3814 if (!channel) {
3815 ret_code = LTTNG_ERR_NOMEM;
3816 goto end;
3817 }
3818
3819 extended = (struct lttng_channel_extended *)
3820 channel->attr.extended.ptr;
3821
3822 ret = get_ust_runtime_stats(
3823 session, uchan, &discarded_events, &lost_packets);
3824 if (ret < 0) {
3825 lttng_channel_destroy(channel);
3826 ret_code = LTTNG_ERR_UNK;
3827 goto end;
3828 }
3829
3830 extended->discarded_events = discarded_events;
3831 extended->lost_packets = lost_packets;
3832
3833 ret = lttng_channel_serialize(channel, &payload->buffer);
3834 if (ret) {
3835 ERR("Failed to serialize lttng_channel: channel name = '%s'",
3836 channel->name);
3837 lttng_channel_destroy(channel);
3838 ret_code = LTTNG_ERR_UNK;
3839 goto end;
3840 }
3841
3842 lttng_channel_destroy(channel);
3843 i++;
3844 }
3845 }
3846
3847 break;
3848 }
3849 default:
3850 break;
3851 }
3852
3853 if (i > UINT32_MAX) {
3854 ERR("Channel count would overflow the channel listing command's reply");
3855 ret_code = LTTNG_ERR_OVERFLOW;
3856 goto end;
3857 }
3858
3859 /* Update command reply header. */
3860 cmd_header.count = (uint32_t) i;
3861 memcpy(payload->buffer.data + cmd_header_offset, &cmd_header, sizeof(cmd_header));
3862 ret_code = LTTNG_OK;
3863
3864 end:
3865 return ret_code;
3866 }
3867
3868 /*
3869 * Command LTTNG_LIST_EVENTS processed by the client thread.
3870 */
3871 enum lttng_error_code cmd_list_events(enum lttng_domain_type domain,
3872 struct ltt_session *session,
3873 char *channel_name,
3874 struct lttng_payload *reply_payload)
3875 {
3876 int buffer_resize_ret;
3877 enum lttng_error_code ret_code = LTTNG_OK;
3878 struct lttcomm_list_command_header reply_command_header = {};
3879 size_t reply_command_header_offset;
3880 unsigned int nb_events = 0;
3881
3882 assert(reply_payload);
3883
3884 /* Reserve space for command reply header. */
3885 reply_command_header_offset = reply_payload->buffer.size;
3886 buffer_resize_ret = lttng_dynamic_buffer_set_size(
3887 &reply_payload->buffer,
3888 reply_command_header_offset + sizeof(struct lttcomm_list_command_header));
3889 if (buffer_resize_ret) {
3890 ret_code = LTTNG_ERR_NOMEM;
3891 goto end;
3892 }
3893
3894 switch (domain) {
3895 case LTTNG_DOMAIN_KERNEL:
3896 if (session->kernel_session != nullptr) {
3897 ret_code = list_lttng_kernel_events(
3898 channel_name, session->kernel_session, reply_payload, &nb_events);
3899 }
3900
3901 break;
3902 case LTTNG_DOMAIN_UST:
3903 {
3904 if (session->ust_session != nullptr) {
3905 ret_code =
3906 list_lttng_ust_global_events(channel_name,
3907 &session->ust_session->domain_global,
3908 reply_payload,
3909 &nb_events);
3910 }
3911
3912 break;
3913 }
3914 case LTTNG_DOMAIN_LOG4J:
3915 case LTTNG_DOMAIN_JUL:
3916 case LTTNG_DOMAIN_PYTHON:
3917 if (session->ust_session) {
3918 struct lttng_ht_iter iter;
3919 struct agent *agt;
3920
3921 lttng::urcu::read_lock_guard read_lock;
3922
3923 cds_lfht_for_each_entry (
3924 session->ust_session->agents->ht, &iter.iter, agt, node.node) {
3925 if (agt->domain == domain) {
3926 ret_code = list_lttng_agent_events(
3927 agt, reply_payload, &nb_events);
3928 break;
3929 }
3930 }
3931 }
3932 break;
3933 default:
3934 ret_code = LTTNG_ERR_UND;
3935 break;
3936 }
3937
3938 if (nb_events > UINT32_MAX) {
3939 ret_code = LTTNG_ERR_OVERFLOW;
3940 goto end;
3941 }
3942
3943 /* Update command reply header. */
3944 reply_command_header.count = (uint32_t) nb_events;
3945 memcpy(reply_payload->buffer.data + reply_command_header_offset,
3946 &reply_command_header,
3947 sizeof(reply_command_header));
3948
3949 end:
3950 return ret_code;
3951 }
3952
3953 /*
3954 * Using the session list, filled a lttng_session array to send back to the
3955 * client for session listing.
3956 *
3957 * The session list lock MUST be acquired before calling this function. Use
3958 * session_lock_list() and session_unlock_list().
3959 */
3960 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3961 size_t session_count,
3962 uid_t uid,
3963 gid_t gid)
3964 {
3965 int ret;
3966 unsigned int i = 0;
3967 struct ltt_session *session;
3968 struct ltt_session_list *list = session_get_list();
3969 struct lttng_session_extended *extended = (typeof(extended)) (&sessions[session_count]);
3970
3971 DBG("Getting all available session for UID %d GID %d", uid, gid);
3972 /*
3973 * Iterate over session list and append data after the control struct in
3974 * the buffer.
3975 */
3976 cds_list_for_each_entry (session, &list->head, list) {
3977 if (!session_get(session)) {
3978 continue;
3979 }
3980 /*
3981 * Only list the sessions the user can control.
3982 */
3983 if (!session_access_ok(session, uid) || session->destroyed) {
3984 session_put(session);
3985 continue;
3986 }
3987
3988 struct ltt_kernel_session *ksess = session->kernel_session;
3989 struct ltt_ust_session *usess = session->ust_session;
3990
3991 if (session->consumer->type == CONSUMER_DST_NET ||
3992 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3993 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3994 ret = build_network_session_path(
3995 sessions[i].path, sizeof(sessions[i].path), session);
3996 } else {
3997 ret = snprintf(sessions[i].path,
3998 sizeof(sessions[i].path),
3999 "%s",
4000 session->consumer->dst.session_root_path);
4001 }
4002 if (ret < 0) {
4003 PERROR("snprintf session path");
4004 session_put(session);
4005 continue;
4006 }
4007
4008 strncpy(sessions[i].name, session->name, NAME_MAX);
4009 sessions[i].name[NAME_MAX - 1] = '\0';
4010 sessions[i].enabled = session->active;
4011 sessions[i].snapshot_mode = session->snapshot_mode;
4012 sessions[i].live_timer_interval = session->live_timer;
4013 extended[i].creation_time.value = (uint64_t) session->creation_time;
4014 extended[i].creation_time.is_set = 1;
4015 i++;
4016 session_put(session);
4017 }
4018 }
4019
4020 /*
4021 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
4022 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
4023 */
4024 int cmd_data_pending(struct ltt_session *session)
4025 {
4026 int ret;
4027 struct ltt_kernel_session *ksess = session->kernel_session;
4028 struct ltt_ust_session *usess = session->ust_session;
4029
4030 LTTNG_ASSERT(session);
4031
4032 DBG("Data pending for session %s", session->name);
4033
4034 /* Session MUST be stopped to ask for data availability. */
4035 if (session->active) {
4036 ret = LTTNG_ERR_SESSION_STARTED;
4037 goto error;
4038 } else {
4039 /*
4040 * If stopped, just make sure we've started before else the above call
4041 * will always send that there is data pending.
4042 *
4043 * The consumer assumes that when the data pending command is received,
4044 * the trace has been started before or else no output data is written
4045 * by the streams which is a condition for data pending. So, this is
4046 * *VERY* important that we don't ask the consumer before a start
4047 * trace.
4048 */
4049 if (!session->has_been_started) {
4050 ret = 0;
4051 goto error;
4052 }
4053 }
4054
4055 /* A rotation is still pending, we have to wait. */
4056 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4057 DBG("Rotate still pending for session %s", session->name);
4058 ret = 1;
4059 goto error;
4060 }
4061
4062 if (ksess && ksess->consumer) {
4063 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
4064 if (ret == 1) {
4065 /* Data is still being extracted for the kernel. */
4066 goto error;
4067 }
4068 }
4069
4070 if (usess && usess->consumer) {
4071 ret = consumer_is_data_pending(usess->id, usess->consumer);
4072 if (ret == 1) {
4073 /* Data is still being extracted for the kernel. */
4074 goto error;
4075 }
4076 }
4077
4078 /* Data is ready to be read by a viewer */
4079 ret = 0;
4080
4081 error:
4082 return ret;
4083 }
4084
4085 /*
4086 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
4087 *
4088 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4089 */
4090 int cmd_snapshot_add_output(struct ltt_session *session,
4091 const struct lttng_snapshot_output *output,
4092 uint32_t *id)
4093 {
4094 int ret;
4095 struct snapshot_output *new_output;
4096
4097 LTTNG_ASSERT(session);
4098 LTTNG_ASSERT(output);
4099
4100 DBG("Cmd snapshot add output for session %s", session->name);
4101
4102 /*
4103 * Can't create an output if the session is not set in no-output mode.
4104 */
4105 if (session->output_traces) {
4106 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4107 goto error;
4108 }
4109
4110 if (session->has_non_mmap_channel) {
4111 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
4112 goto error;
4113 }
4114
4115 /* Only one output is allowed until we have the "tee" feature. */
4116 if (session->snapshot.nb_output == 1) {
4117 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
4118 goto error;
4119 }
4120
4121 new_output = snapshot_output_alloc();
4122 if (!new_output) {
4123 ret = LTTNG_ERR_NOMEM;
4124 goto error;
4125 }
4126
4127 ret = snapshot_output_init(session,
4128 output->max_size,
4129 output->name,
4130 output->ctrl_url,
4131 output->data_url,
4132 session->consumer,
4133 new_output,
4134 &session->snapshot);
4135 if (ret < 0) {
4136 if (ret == -ENOMEM) {
4137 ret = LTTNG_ERR_NOMEM;
4138 } else {
4139 ret = LTTNG_ERR_INVALID;
4140 }
4141 goto free_error;
4142 }
4143
4144 snapshot_add_output(&session->snapshot, new_output);
4145 if (id) {
4146 *id = new_output->id;
4147 }
4148
4149 return LTTNG_OK;
4150
4151 free_error:
4152 snapshot_output_destroy(new_output);
4153 error:
4154 return ret;
4155 }
4156
4157 /*
4158 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
4159 *
4160 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4161 */
4162 int cmd_snapshot_del_output(struct ltt_session *session, const struct lttng_snapshot_output *output)
4163 {
4164 int ret;
4165 struct snapshot_output *sout = nullptr;
4166
4167 LTTNG_ASSERT(session);
4168 LTTNG_ASSERT(output);
4169
4170 lttng::urcu::read_lock_guard read_lock;
4171
4172 /*
4173 * Permission denied to create an output if the session is not
4174 * set in no output mode.
4175 */
4176 if (session->output_traces) {
4177 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4178 goto error;
4179 }
4180
4181 if (output->id) {
4182 DBG("Cmd snapshot del output id %" PRIu32 " for session %s",
4183 output->id,
4184 session->name);
4185 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
4186 } else if (*output->name != '\0') {
4187 DBG("Cmd snapshot del output name %s for session %s", output->name, session->name);
4188 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
4189 }
4190 if (!sout) {
4191 ret = LTTNG_ERR_INVALID;
4192 goto error;
4193 }
4194
4195 snapshot_delete_output(&session->snapshot, sout);
4196 snapshot_output_destroy(sout);
4197 ret = LTTNG_OK;
4198
4199 error:
4200 return ret;
4201 }
4202
4203 /*
4204 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
4205 *
4206 * If no output is available, outputs is untouched and 0 is returned.
4207 *
4208 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
4209 */
4210 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
4211 struct lttng_snapshot_output **outputs)
4212 {
4213 int ret, idx = 0;
4214 struct lttng_snapshot_output *list = nullptr;
4215 struct lttng_ht_iter iter;
4216 struct snapshot_output *output;
4217
4218 LTTNG_ASSERT(session);
4219 LTTNG_ASSERT(outputs);
4220
4221 DBG("Cmd snapshot list outputs for session %s", session->name);
4222
4223 /*
4224 * Permission denied to create an output if the session is not
4225 * set in no output mode.
4226 */
4227 if (session->output_traces) {
4228 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4229 goto end;
4230 }
4231
4232 if (session->snapshot.nb_output == 0) {
4233 ret = 0;
4234 goto end;
4235 }
4236
4237 list = calloc<lttng_snapshot_output>(session->snapshot.nb_output);
4238 if (!list) {
4239 ret = -LTTNG_ERR_NOMEM;
4240 goto end;
4241 }
4242
4243 /* Copy list from session to the new list object. */
4244 {
4245 lttng::urcu::read_lock_guard read_lock;
4246
4247 cds_lfht_for_each_entry (
4248 session->snapshot.output_ht->ht, &iter.iter, output, node.node) {
4249 LTTNG_ASSERT(output->consumer);
4250 list[idx].id = output->id;
4251 list[idx].max_size = output->max_size;
4252 if (lttng_strncpy(list[idx].name, output->name, sizeof(list[idx].name))) {
4253 ret = -LTTNG_ERR_INVALID;
4254 goto error;
4255 }
4256
4257 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4258 if (lttng_strncpy(list[idx].ctrl_url,
4259 output->consumer->dst.session_root_path,
4260 sizeof(list[idx].ctrl_url))) {
4261 ret = -LTTNG_ERR_INVALID;
4262 goto error;
4263 }
4264 } else {
4265 /* Control URI. */
4266 ret = uri_to_str_url(&output->consumer->dst.net.control,
4267 list[idx].ctrl_url,
4268 sizeof(list[idx].ctrl_url));
4269 if (ret < 0) {
4270 ret = -LTTNG_ERR_NOMEM;
4271 goto error;
4272 }
4273
4274 /* Data URI. */
4275 ret = uri_to_str_url(&output->consumer->dst.net.data,
4276 list[idx].data_url,
4277 sizeof(list[idx].data_url));
4278 if (ret < 0) {
4279 ret = -LTTNG_ERR_NOMEM;
4280 goto error;
4281 }
4282 }
4283
4284 idx++;
4285 }
4286 }
4287
4288 *outputs = list;
4289 list = nullptr;
4290 ret = session->snapshot.nb_output;
4291 error:
4292 free(list);
4293 end:
4294 return ret;
4295 }
4296
4297 /*
4298 * Check if we can regenerate the metadata for this session.
4299 * Only kernel, UST per-uid and non-live sessions are supported.
4300 *
4301 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4302 */
4303 static int check_regenerate_metadata_support(struct ltt_session *session)
4304 {
4305 int ret;
4306
4307 LTTNG_ASSERT(session);
4308
4309 if (session->live_timer != 0) {
4310 ret = LTTNG_ERR_LIVE_SESSION;
4311 goto end;
4312 }
4313 if (!session->active) {
4314 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4315 goto end;
4316 }
4317 if (session->ust_session) {
4318 switch (session->ust_session->buffer_type) {
4319 case LTTNG_BUFFER_PER_UID:
4320 break;
4321 case LTTNG_BUFFER_PER_PID:
4322 ret = LTTNG_ERR_PER_PID_SESSION;
4323 goto end;
4324 default:
4325 abort();
4326 ret = LTTNG_ERR_UNK;
4327 goto end;
4328 }
4329 }
4330 if (session->consumer->type == CONSUMER_DST_NET &&
4331 session->consumer->relay_minor_version < 8) {
4332 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4333 goto end;
4334 }
4335 ret = 0;
4336
4337 end:
4338 return ret;
4339 }
4340
4341 /*
4342 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4343 *
4344 * Ask the consumer to truncate the existing metadata file(s) and
4345 * then regenerate the metadata. Live and per-pid sessions are not
4346 * supported and return an error.
4347 *
4348 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4349 */
4350 int cmd_regenerate_metadata(struct ltt_session *session)
4351 {
4352 int ret;
4353
4354 LTTNG_ASSERT(session);
4355
4356 ret = check_regenerate_metadata_support(session);
4357 if (ret) {
4358 goto end;
4359 }
4360
4361 if (session->kernel_session) {
4362 ret = kernctl_session_regenerate_metadata(session->kernel_session->fd);
4363 if (ret < 0) {
4364 ERR("Failed to regenerate the kernel metadata");
4365 goto end;
4366 }
4367 }
4368
4369 if (session->ust_session) {
4370 ret = trace_ust_regenerate_metadata(session->ust_session);
4371 if (ret < 0) {
4372 ERR("Failed to regenerate the UST metadata");
4373 goto end;
4374 }
4375 }
4376 DBG("Cmd metadata regenerate for session %s", session->name);
4377 ret = LTTNG_OK;
4378
4379 end:
4380 return ret;
4381 }
4382
4383 /*
4384 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4385 *
4386 * Ask the tracer to regenerate a new statedump.
4387 *
4388 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4389 */
4390 int cmd_regenerate_statedump(struct ltt_session *session)
4391 {
4392 int ret;
4393
4394 LTTNG_ASSERT(session);
4395
4396 if (!session->active) {
4397 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4398 goto end;
4399 }
4400
4401 if (session->kernel_session) {
4402 ret = kernctl_session_regenerate_statedump(session->kernel_session->fd);
4403 /*
4404 * Currently, the statedump in kernel can only fail if out
4405 * of memory.
4406 */
4407 if (ret < 0) {
4408 if (ret == -ENOMEM) {
4409 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4410 } else {
4411 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4412 }
4413 ERR("Failed to regenerate the kernel statedump");
4414 goto end;
4415 }
4416 }
4417
4418 if (session->ust_session) {
4419 ret = ust_app_regenerate_statedump_all(session->ust_session);
4420 /*
4421 * Currently, the statedump in UST always returns 0.
4422 */
4423 if (ret < 0) {
4424 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4425 ERR("Failed to regenerate the UST statedump");
4426 goto end;
4427 }
4428 }
4429 DBG("Cmd regenerate statedump for session %s", session->name);
4430 ret = LTTNG_OK;
4431
4432 end:
4433 return ret;
4434 }
4435
4436 static enum lttng_error_code
4437 synchronize_tracer_notifier_register(struct notification_thread_handle *notification_thread,
4438 struct lttng_trigger *trigger,
4439 const struct lttng_credentials *cmd_creds)
4440 {
4441 enum lttng_error_code ret_code;
4442 const struct lttng_condition *condition = lttng_trigger_get_const_condition(trigger);
4443 const char *trigger_name;
4444 uid_t trigger_owner;
4445 enum lttng_trigger_status trigger_status;
4446 const enum lttng_domain_type trigger_domain =
4447 lttng_trigger_get_underlying_domain_type_restriction(trigger);
4448
4449 trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
4450 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4451
4452 LTTNG_ASSERT(condition);
4453 LTTNG_ASSERT(lttng_condition_get_type(condition) ==
4454 LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES);
4455
4456 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4457 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
4458
4459 session_lock_list();
4460 switch (trigger_domain) {
4461 case LTTNG_DOMAIN_KERNEL:
4462 {
4463 ret_code = kernel_register_event_notifier(trigger, cmd_creds);
4464 if (ret_code != LTTNG_OK) {
4465 enum lttng_error_code notif_thread_unregister_ret;
4466
4467 notif_thread_unregister_ret =
4468 notification_thread_command_unregister_trigger(notification_thread,
4469 trigger);
4470
4471 if (notif_thread_unregister_ret != LTTNG_OK) {
4472 /* Return the original error code. */
4473 ERR("Failed to unregister trigger from notification thread during error recovery: trigger name = '%s', trigger owner uid = %d, error code = %d",
4474 trigger_name,
4475 (int) trigger_owner,
4476 ret_code);
4477 }
4478
4479 goto end_unlock_session_list;
4480 }
4481 break;
4482 }
4483 case LTTNG_DOMAIN_UST:
4484 ust_app_global_update_all_event_notifier_rules();
4485 break;
4486 case LTTNG_DOMAIN_JUL:
4487 case LTTNG_DOMAIN_LOG4J:
4488 case LTTNG_DOMAIN_PYTHON:
4489 {
4490 /* Agent domains. */
4491 struct agent *agt = agent_find_by_event_notifier_domain(trigger_domain);
4492
4493 if (!agt) {
4494 agt = agent_create(trigger_domain);
4495 if (!agt) {
4496 ret_code = LTTNG_ERR_NOMEM;
4497 goto end_unlock_session_list;
4498 }
4499
4500 agent_add(agt, the_trigger_agents_ht_by_domain);
4501 }
4502
4503 ret_code = (lttng_error_code) trigger_agent_enable(trigger, agt);
4504 if (ret_code != LTTNG_OK) {
4505 goto end_unlock_session_list;
4506 }
4507
4508 break;
4509 }
4510 case LTTNG_DOMAIN_NONE:
4511 default:
4512 abort();
4513 }
4514
4515 ret_code = LTTNG_OK;
4516 end_unlock_session_list:
4517 session_unlock_list();
4518 return ret_code;
4519 }
4520
4521 enum lttng_error_code cmd_register_trigger(const struct lttng_credentials *cmd_creds,
4522 struct lttng_trigger *trigger,
4523 bool is_trigger_anonymous,
4524 struct notification_thread_handle *notification_thread,
4525 struct lttng_trigger **return_trigger)
4526 {
4527 enum lttng_error_code ret_code;
4528 const char *trigger_name;
4529 uid_t trigger_owner;
4530 enum lttng_trigger_status trigger_status;
4531
4532 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4533 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
4534
4535 trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
4536 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4537
4538 DBG("Running register trigger command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4539 trigger_name,
4540 (int) trigger_owner,
4541 (int) lttng_credentials_get_uid(cmd_creds));
4542
4543 /*
4544 * Validate the trigger credentials against the command credentials.
4545 * Only the root user can register a trigger with non-matching
4546 * credentials.
4547 */
4548 if (!lttng_credentials_is_equal_uid(lttng_trigger_get_credentials(trigger), cmd_creds)) {
4549 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4550 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4551 trigger_name,
4552 (int) trigger_owner,
4553 (int) lttng_credentials_get_uid(cmd_creds));
4554 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4555 goto end;
4556 }
4557 }
4558
4559 /*
4560 * The bytecode generation also serves as a validation step for the
4561 * bytecode expressions.
4562 */
4563 ret_code = lttng_trigger_generate_bytecode(trigger, cmd_creds);
4564 if (ret_code != LTTNG_OK) {
4565 ERR("Failed to generate bytecode of trigger: trigger name = '%s', trigger owner uid = %d, error code = %d",
4566 trigger_name,
4567 (int) trigger_owner,
4568 ret_code);
4569 goto end;
4570 }
4571
4572 /*
4573 * A reference to the trigger is acquired by the notification thread.
4574 * It is safe to return the same trigger to the caller since it the
4575 * other user holds a reference.
4576 *
4577 * The trigger is modified during the execution of the
4578 * "register trigger" command. However, by the time the command returns,
4579 * it is safe to use without any locking as its properties are
4580 * immutable.
4581 */
4582 ret_code = notification_thread_command_register_trigger(
4583 notification_thread, trigger, is_trigger_anonymous);
4584 if (ret_code != LTTNG_OK) {
4585 DBG("Failed to register trigger to notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
4586 trigger_name,
4587 (int) trigger_owner,
4588 ret_code);
4589 goto end;
4590 }
4591
4592 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4593 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
4594
4595 /*
4596 * Synchronize tracers if the trigger adds an event notifier.
4597 */
4598 if (lttng_trigger_needs_tracer_notifier(trigger)) {
4599 ret_code = synchronize_tracer_notifier_register(
4600 notification_thread, trigger, cmd_creds);
4601 if (ret_code != LTTNG_OK) {
4602 ERR("Error registering tracer notifier: %s", lttng_strerror(-ret_code));
4603 goto end;
4604 }
4605 }
4606
4607 /*
4608 * Return an updated trigger to the client.
4609 *
4610 * Since a modified version of the same trigger is returned, acquire a
4611 * reference to the trigger so the caller doesn't have to care if those
4612 * are distinct instances or not.
4613 */
4614 if (ret_code == LTTNG_OK) {
4615 lttng_trigger_get(trigger);
4616 *return_trigger = trigger;
4617 /* Ownership of trigger was transferred to caller. */
4618 trigger = nullptr;
4619 }
4620 end:
4621 return ret_code;
4622 }
4623
4624 static enum lttng_error_code
4625 synchronize_tracer_notifier_unregister(const struct lttng_trigger *trigger)
4626 {
4627 enum lttng_error_code ret_code;
4628 const struct lttng_condition *condition = lttng_trigger_get_const_condition(trigger);
4629 const enum lttng_domain_type trigger_domain =
4630 lttng_trigger_get_underlying_domain_type_restriction(trigger);
4631
4632 LTTNG_ASSERT(condition);
4633 LTTNG_ASSERT(lttng_condition_get_type(condition) ==
4634 LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES);
4635
4636 session_lock_list();
4637 switch (trigger_domain) {
4638 case LTTNG_DOMAIN_KERNEL:
4639 ret_code = kernel_unregister_event_notifier(trigger);
4640 if (ret_code != LTTNG_OK) {
4641 goto end_unlock_session_list;
4642 }
4643
4644 break;
4645 case LTTNG_DOMAIN_UST:
4646 ust_app_global_update_all_event_notifier_rules();
4647 break;
4648 case LTTNG_DOMAIN_JUL:
4649 case LTTNG_DOMAIN_LOG4J:
4650 case LTTNG_DOMAIN_PYTHON:
4651 {
4652 /* Agent domains. */
4653 struct agent *agt = agent_find_by_event_notifier_domain(trigger_domain);
4654
4655 /*
4656 * This trigger was never registered in the first place. Calling
4657 * this function under those circumstances is an internal error.
4658 */
4659 LTTNG_ASSERT(agt);
4660 ret_code = (lttng_error_code) trigger_agent_disable(trigger, agt);
4661 if (ret_code != LTTNG_OK) {
4662 goto end_unlock_session_list;
4663 }
4664
4665 break;
4666 }
4667 case LTTNG_DOMAIN_NONE:
4668 default:
4669 abort();
4670 }
4671
4672 ret_code = LTTNG_OK;
4673
4674 end_unlock_session_list:
4675 session_unlock_list();
4676 return ret_code;
4677 }
4678
4679 enum lttng_error_code cmd_unregister_trigger(const struct lttng_credentials *cmd_creds,
4680 const struct lttng_trigger *trigger,
4681 struct notification_thread_handle *notification_thread)
4682 {
4683 enum lttng_error_code ret_code;
4684 const char *trigger_name;
4685 uid_t trigger_owner;
4686 enum lttng_trigger_status trigger_status;
4687 struct lttng_trigger *sessiond_trigger = nullptr;
4688
4689 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4690 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
4691 trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
4692 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4693
4694 DBG("Running unregister trigger command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4695 trigger_name,
4696 (int) trigger_owner,
4697 (int) lttng_credentials_get_uid(cmd_creds));
4698
4699 /*
4700 * Validate the trigger credentials against the command credentials.
4701 * Only the root user can unregister a trigger with non-matching
4702 * credentials.
4703 */
4704 if (!lttng_credentials_is_equal_uid(lttng_trigger_get_credentials(trigger), cmd_creds)) {
4705 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4706 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4707 trigger_name,
4708 (int) trigger_owner,
4709 (int) lttng_credentials_get_uid(cmd_creds));
4710 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4711 goto end;
4712 }
4713 }
4714
4715 /* Fetch the sessiond side trigger object. */
4716 ret_code = notification_thread_command_get_trigger(
4717 notification_thread, trigger, &sessiond_trigger);
4718 if (ret_code != LTTNG_OK) {
4719 DBG("Failed to get trigger from notification thread during unregister: trigger name = '%s', trigger owner uid = %d, error code = %d",
4720 trigger_name,
4721 (int) trigger_owner,
4722 ret_code);
4723 goto end;
4724 }
4725
4726 LTTNG_ASSERT(sessiond_trigger);
4727
4728 /*
4729 * From this point on, no matter what, consider the trigger
4730 * unregistered.
4731 *
4732 * We set the unregistered state of the sessiond side trigger object in
4733 * the client thread since we want to minimize the possibility of the
4734 * notification thread being stalled due to a long execution of an
4735 * action that required the trigger lock.
4736 */
4737 lttng_trigger_set_as_unregistered(sessiond_trigger);
4738
4739 ret_code = notification_thread_command_unregister_trigger(notification_thread, trigger);
4740 if (ret_code != LTTNG_OK) {
4741 DBG("Failed to unregister trigger from notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
4742 trigger_name,
4743 (int) trigger_owner,
4744 ret_code);
4745 goto end;
4746 }
4747
4748 /*
4749 * Synchronize tracers if the trigger removes an event notifier.
4750 * Do this even if the trigger unregistration failed to at least stop
4751 * the tracers from producing notifications associated with this
4752 * event notifier.
4753 */
4754 if (lttng_trigger_needs_tracer_notifier(trigger)) {
4755 ret_code = synchronize_tracer_notifier_unregister(trigger);
4756 if (ret_code != LTTNG_OK) {
4757 ERR("Error unregistering trigger to tracer.");
4758 goto end;
4759 }
4760 }
4761
4762 end:
4763 lttng_trigger_put(sessiond_trigger);
4764 return ret_code;
4765 }
4766
4767 enum lttng_error_code cmd_list_triggers(struct command_ctx *cmd_ctx,
4768 struct notification_thread_handle *notification_thread,
4769 struct lttng_triggers **return_triggers)
4770 {
4771 int ret;
4772 enum lttng_error_code ret_code;
4773 struct lttng_triggers *triggers = nullptr;
4774
4775 /* Get the set of triggers from the notification thread. */
4776 ret_code = notification_thread_command_list_triggers(
4777 notification_thread, cmd_ctx->creds.uid, &triggers);
4778 if (ret_code != LTTNG_OK) {
4779 goto end;
4780 }
4781
4782 ret = lttng_triggers_remove_hidden_triggers(triggers);
4783 if (ret) {
4784 ret_code = LTTNG_ERR_UNK;
4785 goto end;
4786 }
4787
4788 *return_triggers = triggers;
4789 triggers = nullptr;
4790 ret_code = LTTNG_OK;
4791 end:
4792 lttng_triggers_destroy(triggers);
4793 return ret_code;
4794 }
4795
4796 enum lttng_error_code
4797 cmd_execute_error_query(const struct lttng_credentials *cmd_creds,
4798 const struct lttng_error_query *query,
4799 struct lttng_error_query_results **_results,
4800 struct notification_thread_handle *notification_thread)
4801 {
4802 enum lttng_error_code ret_code;
4803 const struct lttng_trigger *query_target_trigger;
4804 const struct lttng_action *query_target_action = nullptr;
4805 struct lttng_trigger *matching_trigger = nullptr;
4806 const char *trigger_name;
4807 uid_t trigger_owner;
4808 enum lttng_trigger_status trigger_status;
4809 struct lttng_error_query_results *results = nullptr;
4810
4811 switch (lttng_error_query_get_target_type(query)) {
4812 case LTTNG_ERROR_QUERY_TARGET_TYPE_TRIGGER:
4813 query_target_trigger = lttng_error_query_trigger_borrow_target(query);
4814 break;
4815 case LTTNG_ERROR_QUERY_TARGET_TYPE_CONDITION:
4816 query_target_trigger = lttng_error_query_condition_borrow_target(query);
4817 break;
4818 case LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION:
4819 query_target_trigger = lttng_error_query_action_borrow_trigger_target(query);
4820 break;
4821 default:
4822 abort();
4823 }
4824
4825 LTTNG_ASSERT(query_target_trigger);
4826
4827 ret_code = notification_thread_command_get_trigger(
4828 notification_thread, query_target_trigger, &matching_trigger);
4829 if (ret_code != LTTNG_OK) {
4830 goto end;
4831 }
4832
4833 /* No longer needed. */
4834 query_target_trigger = nullptr;
4835
4836 if (lttng_error_query_get_target_type(query) == LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION) {
4837 /* Get the sessiond-side version of the target action. */
4838 query_target_action =
4839 lttng_error_query_action_borrow_action_target(query, matching_trigger);
4840 }
4841
4842 trigger_status = lttng_trigger_get_name(matching_trigger, &trigger_name);
4843 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
4844 trigger_status = lttng_trigger_get_owner_uid(matching_trigger, &trigger_owner);
4845 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4846
4847 results = lttng_error_query_results_create();
4848 if (!results) {
4849 ret_code = LTTNG_ERR_NOMEM;
4850 goto end;
4851 }
4852
4853 DBG("Running \"execute error query\" command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4854 trigger_name,
4855 (int) trigger_owner,
4856 (int) lttng_credentials_get_uid(cmd_creds));
4857
4858 /*
4859 * Validate the trigger credentials against the command credentials.
4860 * Only the root user can target a trigger with non-matching
4861 * credentials.
4862 */
4863 if (!lttng_credentials_is_equal_uid(lttng_trigger_get_credentials(matching_trigger),
4864 cmd_creds)) {
4865 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4866 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4867 trigger_name,
4868 (int) trigger_owner,
4869 (int) lttng_credentials_get_uid(cmd_creds));
4870 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4871 goto end;
4872 }
4873 }
4874
4875 switch (lttng_error_query_get_target_type(query)) {
4876 case LTTNG_ERROR_QUERY_TARGET_TYPE_TRIGGER:
4877 trigger_status = lttng_trigger_add_error_results(matching_trigger, results);
4878
4879 switch (trigger_status) {
4880 case LTTNG_TRIGGER_STATUS_OK:
4881 break;
4882 default:
4883 ret_code = LTTNG_ERR_UNK;
4884 goto end;
4885 }
4886
4887 break;
4888 case LTTNG_ERROR_QUERY_TARGET_TYPE_CONDITION:
4889 {
4890 trigger_status =
4891 lttng_trigger_condition_add_error_results(matching_trigger, results);
4892
4893 switch (trigger_status) {
4894 case LTTNG_TRIGGER_STATUS_OK:
4895 break;
4896 default:
4897 ret_code = LTTNG_ERR_UNK;
4898 goto end;
4899 }
4900
4901 break;
4902 }
4903 case LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION:
4904 {
4905 const enum lttng_action_status action_status =
4906 lttng_action_add_error_query_results(query_target_action, results);
4907
4908 switch (action_status) {
4909 case LTTNG_ACTION_STATUS_OK:
4910 break;
4911 default:
4912 ret_code = LTTNG_ERR_UNK;
4913 goto end;
4914 }
4915
4916 break;
4917 }
4918 default:
4919 abort();
4920 break;
4921 }
4922
4923 *_results = results;
4924 results = nullptr;
4925 ret_code = LTTNG_OK;
4926 end:
4927 lttng_trigger_put(matching_trigger);
4928 lttng_error_query_results_destroy(results);
4929 return ret_code;
4930 }
4931
4932 /*
4933 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4934 * snapshot output is *not* set with a remote destination.
4935 *
4936 * Return LTTNG_OK on success or a LTTNG_ERR code.
4937 */
4938 static enum lttng_error_code set_relayd_for_snapshot(struct consumer_output *output,
4939 const struct ltt_session *session)
4940 {
4941 enum lttng_error_code status = LTTNG_OK;
4942 struct lttng_ht_iter iter;
4943 struct consumer_socket *socket;
4944 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4945 const char *base_path;
4946
4947 LTTNG_ASSERT(output);
4948 LTTNG_ASSERT(session);
4949
4950 DBG2("Set relayd object from snapshot output");
4951
4952 if (session->current_trace_chunk) {
4953 enum lttng_trace_chunk_status chunk_status = lttng_trace_chunk_get_id(
4954 session->current_trace_chunk, &current_chunk_id.value);
4955
4956 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4957 current_chunk_id.is_set = true;
4958 } else {
4959 ERR("Failed to get current trace chunk id");
4960 status = LTTNG_ERR_UNK;
4961 goto error;
4962 }
4963 }
4964
4965 /* Ignore if snapshot consumer output is not network. */
4966 if (output->type != CONSUMER_DST_NET) {
4967 goto error;
4968 }
4969
4970 /*
4971 * The snapshot record URI base path overrides the session
4972 * base path.
4973 */
4974 if (output->dst.net.control.subdir[0] != '\0') {
4975 base_path = output->dst.net.control.subdir;
4976 } else {
4977 base_path = session->base_path;
4978 }
4979
4980 /*
4981 * For each consumer socket, create and send the relayd object of the
4982 * snapshot output.
4983 */
4984 {
4985 lttng::urcu::read_lock_guard read_lock;
4986
4987 cds_lfht_for_each_entry (output->socks->ht, &iter.iter, socket, node.node) {
4988 pthread_mutex_lock(socket->lock);
4989 status = send_consumer_relayd_sockets(
4990 session->id,
4991 output,
4992 socket,
4993 session->name,
4994 session->hostname,
4995 base_path,
4996 session->live_timer,
4997 current_chunk_id.is_set ? &current_chunk_id.value : nullptr,
4998 session->creation_time,
4999 session->name_contains_creation_time);
5000 pthread_mutex_unlock(socket->lock);
5001 if (status != LTTNG_OK) {
5002 goto error;
5003 }
5004 }
5005 }
5006
5007 error:
5008 return status;
5009 }
5010
5011 /*
5012 * Record a kernel snapshot.
5013 *
5014 * Return LTTNG_OK on success or a LTTNG_ERR code.
5015 */
5016 static enum lttng_error_code record_kernel_snapshot(struct ltt_kernel_session *ksess,
5017 const struct consumer_output *output,
5018 const struct ltt_session *session,
5019 uint64_t nb_packets_per_stream)
5020 {
5021 enum lttng_error_code status;
5022
5023 LTTNG_ASSERT(ksess);
5024 LTTNG_ASSERT(output);
5025 LTTNG_ASSERT(session);
5026
5027 status = kernel_snapshot_record(ksess, output, nb_packets_per_stream);
5028 return status;
5029 }
5030
5031 /*
5032 * Record a UST snapshot.
5033 *
5034 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
5035 */
5036 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
5037 const struct consumer_output *output,
5038 const struct ltt_session *session,
5039 uint64_t nb_packets_per_stream)
5040 {
5041 enum lttng_error_code status;
5042
5043 LTTNG_ASSERT(usess);
5044 LTTNG_ASSERT(output);
5045 LTTNG_ASSERT(session);
5046
5047 status = ust_app_snapshot_record(usess, output, nb_packets_per_stream);
5048 return status;
5049 }
5050
5051 static uint64_t get_session_size_one_more_packet_per_stream(const struct ltt_session *session,
5052 uint64_t cur_nr_packets)
5053 {
5054 uint64_t tot_size = 0;
5055
5056 if (session->kernel_session) {
5057 struct ltt_kernel_channel *chan;
5058 const struct ltt_kernel_session *ksess = session->kernel_session;
5059
5060 cds_list_for_each_entry (chan, &ksess->channel_list.head, list) {
5061 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
5062 /*
5063 * Don't take channel into account if we
5064 * already grab all its packets.
5065 */
5066 continue;
5067 }
5068 tot_size += chan->channel->attr.subbuf_size * chan->stream_count;
5069 }
5070 }
5071
5072 if (session->ust_session) {
5073 const struct ltt_ust_session *usess = session->ust_session;
5074
5075 tot_size += ust_app_get_size_one_more_packet_per_stream(usess, cur_nr_packets);
5076 }
5077
5078 return tot_size;
5079 }
5080
5081 /*
5082 * Calculate the number of packets we can grab from each stream that
5083 * fits within the overall snapshot max size.
5084 *
5085 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
5086 * the number of packets per stream.
5087 *
5088 * TODO: this approach is not perfect: we consider the worse case
5089 * (packet filling the sub-buffers) as an upper bound, but we could do
5090 * better if we do this calculation while we actually grab the packet
5091 * content: we would know how much padding we don't actually store into
5092 * the file.
5093 *
5094 * This algorithm is currently bounded by the number of packets per
5095 * stream.
5096 *
5097 * Since we call this algorithm before actually grabbing the data, it's
5098 * an approximation: for instance, applications could appear/disappear
5099 * in between this call and actually grabbing data.
5100 */
5101 static int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
5102 uint64_t max_size)
5103 {
5104 int64_t size_left;
5105 uint64_t cur_nb_packets = 0;
5106
5107 if (!max_size) {
5108 return 0; /* Infinite */
5109 }
5110
5111 size_left = max_size;
5112 for (;;) {
5113 uint64_t one_more_packet_tot_size;
5114
5115 one_more_packet_tot_size =
5116 get_session_size_one_more_packet_per_stream(session, cur_nb_packets);
5117 if (!one_more_packet_tot_size) {
5118 /* We are already grabbing all packets. */
5119 break;
5120 }
5121 size_left -= one_more_packet_tot_size;
5122 if (size_left < 0) {
5123 break;
5124 }
5125 cur_nb_packets++;
5126 }
5127 if (!cur_nb_packets && size_left != max_size) {
5128 /* Not enough room to grab one packet of each stream, error. */
5129 return -1;
5130 }
5131 return cur_nb_packets;
5132 }
5133
5134 static enum lttng_error_code snapshot_record(struct ltt_session *session,
5135 const struct snapshot_output *snapshot_output)
5136 {
5137 int64_t nb_packets_per_stream;
5138 char snapshot_chunk_name[LTTNG_NAME_MAX];
5139 int ret;
5140 enum lttng_error_code ret_code = LTTNG_OK;
5141 struct lttng_trace_chunk *snapshot_trace_chunk;
5142 struct consumer_output *original_ust_consumer_output = nullptr;
5143 struct consumer_output *original_kernel_consumer_output = nullptr;
5144 struct consumer_output *snapshot_ust_consumer_output = nullptr;
5145 struct consumer_output *snapshot_kernel_consumer_output = nullptr;
5146
5147 ret = snprintf(snapshot_chunk_name,
5148 sizeof(snapshot_chunk_name),
5149 "%s-%s-%" PRIu64,
5150 snapshot_output->name,
5151 snapshot_output->datetime,
5152 snapshot_output->nb_snapshot);
5153 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
5154 ERR("Failed to format snapshot name");
5155 ret_code = LTTNG_ERR_INVALID;
5156 goto error;
5157 }
5158 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
5159 snapshot_output->name,
5160 session->name,
5161 snapshot_chunk_name);
5162 if (!session->kernel_session && !session->ust_session) {
5163 ERR("Failed to record snapshot as no channels exist");
5164 ret_code = LTTNG_ERR_NO_CHANNEL;
5165 goto error;
5166 }
5167
5168 if (session->kernel_session) {
5169 original_kernel_consumer_output = session->kernel_session->consumer;
5170 snapshot_kernel_consumer_output = consumer_copy_output(snapshot_output->consumer);
5171 strcpy(snapshot_kernel_consumer_output->chunk_path, snapshot_chunk_name);
5172
5173 /* Copy the original domain subdir. */
5174 strcpy(snapshot_kernel_consumer_output->domain_subdir,
5175 original_kernel_consumer_output->domain_subdir);
5176
5177 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
5178 original_kernel_consumer_output);
5179 if (ret < 0) {
5180 ERR("Failed to copy consumer sockets from snapshot output configuration");
5181 ret_code = LTTNG_ERR_NOMEM;
5182 goto error;
5183 }
5184 ret_code = set_relayd_for_snapshot(snapshot_kernel_consumer_output, session);
5185 if (ret_code != LTTNG_OK) {
5186 ERR("Failed to setup relay daemon for kernel tracer snapshot");
5187 goto error;
5188 }
5189 session->kernel_session->consumer = snapshot_kernel_consumer_output;
5190 }
5191 if (session->ust_session) {
5192 original_ust_consumer_output = session->ust_session->consumer;
5193 snapshot_ust_consumer_output = consumer_copy_output(snapshot_output->consumer);
5194 strcpy(snapshot_ust_consumer_output->chunk_path, snapshot_chunk_name);
5195
5196 /* Copy the original domain subdir. */
5197 strcpy(snapshot_ust_consumer_output->domain_subdir,
5198 original_ust_consumer_output->domain_subdir);
5199
5200 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
5201 original_ust_consumer_output);
5202 if (ret < 0) {
5203 ERR("Failed to copy consumer sockets from snapshot output configuration");
5204 ret_code = LTTNG_ERR_NOMEM;
5205 goto error;
5206 }
5207 ret_code = set_relayd_for_snapshot(snapshot_ust_consumer_output, session);
5208 if (ret_code != LTTNG_OK) {
5209 ERR("Failed to setup relay daemon for userspace tracer snapshot");
5210 goto error;
5211 }
5212 session->ust_session->consumer = snapshot_ust_consumer_output;
5213 }
5214
5215 snapshot_trace_chunk = session_create_new_trace_chunk(
5216 session,
5217 snapshot_kernel_consumer_output ?: snapshot_ust_consumer_output,
5218 consumer_output_get_base_path(snapshot_output->consumer),
5219 snapshot_chunk_name);
5220 if (!snapshot_trace_chunk) {
5221 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
5222 session->name);
5223 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
5224 goto error;
5225 }
5226 LTTNG_ASSERT(!session->current_trace_chunk);
5227 ret = session_set_trace_chunk(session, snapshot_trace_chunk, nullptr);
5228 lttng_trace_chunk_put(snapshot_trace_chunk);
5229 snapshot_trace_chunk = nullptr;
5230 if (ret) {
5231 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
5232 session->name);
5233 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5234 goto error;
5235 }
5236
5237 nb_packets_per_stream =
5238 get_session_nb_packets_per_stream(session, snapshot_output->max_size);
5239 if (nb_packets_per_stream < 0) {
5240 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
5241 goto error_close_trace_chunk;
5242 }
5243
5244 if (session->kernel_session) {
5245 ret_code = record_kernel_snapshot(session->kernel_session,
5246 snapshot_kernel_consumer_output,
5247 session,
5248 nb_packets_per_stream);
5249 if (ret_code != LTTNG_OK) {
5250 goto error_close_trace_chunk;
5251 }
5252 }
5253
5254 if (session->ust_session) {
5255 ret_code = record_ust_snapshot(session->ust_session,
5256 snapshot_ust_consumer_output,
5257 session,
5258 nb_packets_per_stream);
5259 if (ret_code != LTTNG_OK) {
5260 goto error_close_trace_chunk;
5261 }
5262 }
5263
5264 error_close_trace_chunk:
5265 if (session_set_trace_chunk(session, nullptr, &snapshot_trace_chunk)) {
5266 ERR("Failed to release the current trace chunk of session \"%s\"", session->name);
5267 ret_code = LTTNG_ERR_UNK;
5268 }
5269
5270 if (session_close_trace_chunk(session,
5271 snapshot_trace_chunk,
5272 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION,
5273 nullptr)) {
5274 /*
5275 * Don't goto end; make sure the chunk is closed for the session
5276 * to allow future snapshots.
5277 */
5278 ERR("Failed to close snapshot trace chunk of session \"%s\"", session->name);
5279 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5280 }
5281
5282 lttng_trace_chunk_put(snapshot_trace_chunk);
5283 snapshot_trace_chunk = nullptr;
5284 error:
5285 if (original_ust_consumer_output) {
5286 session->ust_session->consumer = original_ust_consumer_output;
5287 }
5288 if (original_kernel_consumer_output) {
5289 session->kernel_session->consumer = original_kernel_consumer_output;
5290 }
5291 consumer_output_put(snapshot_ust_consumer_output);
5292 consumer_output_put(snapshot_kernel_consumer_output);
5293 return ret_code;
5294 }
5295
5296 /*
5297 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
5298 *
5299 * The wait parameter is ignored so this call always wait for the snapshot to
5300 * complete before returning.
5301 *
5302 * Return LTTNG_OK on success or else a LTTNG_ERR code.
5303 */
5304 int cmd_snapshot_record(struct ltt_session *session,
5305 const struct lttng_snapshot_output *output,
5306 int wait __attribute__((unused)))
5307 {
5308 enum lttng_error_code cmd_ret = LTTNG_OK;
5309 int ret;
5310 unsigned int snapshot_success = 0;
5311 char datetime[16];
5312 struct snapshot_output *tmp_output = nullptr;
5313
5314 LTTNG_ASSERT(session);
5315 LTTNG_ASSERT(output);
5316
5317 DBG("Cmd snapshot record for session %s", session->name);
5318
5319 /* Get the datetime for the snapshot output directory. */
5320 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime, sizeof(datetime));
5321 if (!ret) {
5322 cmd_ret = LTTNG_ERR_INVALID;
5323 goto error;
5324 }
5325
5326 /*
5327 * Permission denied to create an output if the session is not
5328 * set in no output mode.
5329 */
5330 if (session->output_traces) {
5331 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
5332 goto error;
5333 }
5334
5335 /* The session needs to be started at least once. */
5336 if (!session->has_been_started) {
5337 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5338 goto error;
5339 }
5340
5341 /* Use temporary output for the session. */
5342 if (*output->ctrl_url != '\0') {
5343 tmp_output = snapshot_output_alloc();
5344 if (!tmp_output) {
5345 cmd_ret = LTTNG_ERR_NOMEM;
5346 goto error;
5347 }
5348
5349 ret = snapshot_output_init(session,
5350 output->max_size,
5351 output->name,
5352 output->ctrl_url,
5353 output->data_url,
5354 session->consumer,
5355 tmp_output,
5356 nullptr);
5357 if (ret < 0) {
5358 if (ret == -ENOMEM) {
5359 cmd_ret = LTTNG_ERR_NOMEM;
5360 } else {
5361 cmd_ret = LTTNG_ERR_INVALID;
5362 }
5363 goto error;
5364 }
5365 /* Use the global session count for the temporary snapshot. */
5366 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
5367
5368 /* Use the global datetime */
5369 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
5370 cmd_ret = snapshot_record(session, tmp_output);
5371 if (cmd_ret != LTTNG_OK) {
5372 goto error;
5373 }
5374 snapshot_success = 1;
5375 } else {
5376 struct snapshot_output *sout;
5377 struct lttng_ht_iter iter;
5378
5379 lttng::urcu::read_lock_guard read_lock;
5380
5381 cds_lfht_for_each_entry (
5382 session->snapshot.output_ht->ht, &iter.iter, sout, node.node) {
5383 struct snapshot_output output_copy;
5384
5385 /*
5386 * Make a local copy of the output and override output
5387 * parameters with those provided as part of the
5388 * command.
5389 */
5390 memcpy(&output_copy, sout, sizeof(output_copy));
5391
5392 if (output->max_size != (uint64_t) -1ULL) {
5393 output_copy.max_size = output->max_size;
5394 }
5395
5396 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
5397 memcpy(output_copy.datetime, datetime, sizeof(datetime));
5398
5399 /* Use temporary name. */
5400 if (*output->name != '\0') {
5401 if (lttng_strncpy(output_copy.name,
5402 output->name,
5403 sizeof(output_copy.name))) {
5404 cmd_ret = LTTNG_ERR_INVALID;
5405 goto error;
5406 }
5407 }
5408
5409 cmd_ret = snapshot_record(session, &output_copy);
5410 if (cmd_ret != LTTNG_OK) {
5411 goto error;
5412 }
5413
5414 snapshot_success = 1;
5415 }
5416 }
5417
5418 if (snapshot_success) {
5419 session->snapshot.nb_snapshot++;
5420 } else {
5421 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
5422 }
5423
5424 error:
5425 if (tmp_output) {
5426 snapshot_output_destroy(tmp_output);
5427 }
5428
5429 return cmd_ret;
5430 }
5431
5432 /*
5433 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
5434 */
5435 int cmd_set_session_shm_path(struct ltt_session *session, const char *shm_path)
5436 {
5437 /* Safety net */
5438 LTTNG_ASSERT(session);
5439
5440 /*
5441 * Can only set shm path before session is started.
5442 */
5443 if (session->has_been_started) {
5444 return LTTNG_ERR_SESSION_STARTED;
5445 }
5446
5447 strncpy(session->shm_path, shm_path, sizeof(session->shm_path));
5448 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
5449
5450 return LTTNG_OK;
5451 }
5452
5453 /*
5454 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
5455 *
5456 * Ask the consumer to rotate the session output directory.
5457 * The session lock must be held.
5458 *
5459 * Returns LTTNG_OK on success or else a negative LTTng error code.
5460 */
5461 int cmd_rotate_session(struct ltt_session *session,
5462 struct lttng_rotate_session_return *rotate_return,
5463 bool quiet_rotation,
5464 enum lttng_trace_chunk_command_type command)
5465 {
5466 int ret;
5467 uint64_t ongoing_rotation_chunk_id;
5468 enum lttng_error_code cmd_ret = LTTNG_OK;
5469 struct lttng_trace_chunk *chunk_being_archived = nullptr;
5470 struct lttng_trace_chunk *new_trace_chunk = nullptr;
5471 enum lttng_trace_chunk_status chunk_status;
5472 bool failed_to_rotate = false;
5473 enum lttng_error_code rotation_fail_code = LTTNG_OK;
5474
5475 LTTNG_ASSERT(session);
5476
5477 if (!session->has_been_started) {
5478 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5479 goto end;
5480 }
5481
5482 /*
5483 * Explicit rotation is not supported for live sessions.
5484 * However, live sessions can perform a quiet rotation on
5485 * destroy.
5486 * Rotation is not supported for snapshot traces (no output).
5487 */
5488 if ((!quiet_rotation && session->live_timer) || !session->output_traces) {
5489 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5490 goto end;
5491 }
5492
5493 /* Unsupported feature in lttng-relayd before 2.11. */
5494 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
5495 (session->consumer->relay_major_version == 2 &&
5496 session->consumer->relay_minor_version < 11)) {
5497 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
5498 goto end;
5499 }
5500
5501 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
5502 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
5503 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
5504 goto end;
5505 }
5506
5507 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
5508 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
5509 session->name);
5510 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
5511 goto end;
5512 }
5513
5514 /*
5515 * After a stop, we only allow one rotation to occur, the other ones are
5516 * useless until a new start.
5517 */
5518 if (session->rotated_after_last_stop) {
5519 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
5520 session->name);
5521 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
5522 goto end;
5523 }
5524
5525 /*
5526 * After a stop followed by a clear, disallow following rotations a they would
5527 * generate empty chunks.
5528 */
5529 if (session->cleared_after_last_stop) {
5530 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
5531 session->name);
5532 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
5533 goto end;
5534 }
5535
5536 if (session->active) {
5537 new_trace_chunk =
5538 session_create_new_trace_chunk(session, nullptr, nullptr, nullptr);
5539 if (!new_trace_chunk) {
5540 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
5541 goto error;
5542 }
5543 }
5544
5545 /*
5546 * The current trace chunk becomes the chunk being archived.
5547 *
5548 * After this point, "chunk_being_archived" must absolutely
5549 * be closed on the consumer(s), otherwise it will never be
5550 * cleaned-up, which will result in a leak.
5551 */
5552 ret = session_set_trace_chunk(session, new_trace_chunk, &chunk_being_archived);
5553 if (ret) {
5554 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5555 goto error;
5556 }
5557
5558 if (session->kernel_session) {
5559 cmd_ret = kernel_rotate_session(session);
5560 if (cmd_ret != LTTNG_OK) {
5561 failed_to_rotate = true;
5562 rotation_fail_code = cmd_ret;
5563 }
5564 }
5565 if (session->ust_session) {
5566 cmd_ret = ust_app_rotate_session(session);
5567 if (cmd_ret != LTTNG_OK) {
5568 failed_to_rotate = true;
5569 rotation_fail_code = cmd_ret;
5570 }
5571 }
5572
5573 if (!session->active) {
5574 session->rotated_after_last_stop = true;
5575 }
5576
5577 if (!chunk_being_archived) {
5578 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5579 session->name);
5580 if (failed_to_rotate) {
5581 cmd_ret = rotation_fail_code;
5582 goto error;
5583 }
5584 cmd_ret = LTTNG_OK;
5585 goto end;
5586 }
5587
5588 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5589 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived, &ongoing_rotation_chunk_id);
5590 LTTNG_ASSERT(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5591
5592 ret = session_close_trace_chunk(
5593 session, chunk_being_archived, command, session->last_chunk_path);
5594 if (ret) {
5595 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5596 goto error;
5597 }
5598
5599 if (failed_to_rotate) {
5600 cmd_ret = rotation_fail_code;
5601 goto error;
5602 }
5603
5604 session->quiet_rotation = quiet_rotation;
5605 ret = timer_session_rotation_pending_check_start(session, DEFAULT_ROTATE_PENDING_TIMER);
5606 if (ret) {
5607 cmd_ret = LTTNG_ERR_UNK;
5608 goto error;
5609 }
5610
5611 if (rotate_return) {
5612 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5613 }
5614
5615 session->chunk_being_archived = chunk_being_archived;
5616 chunk_being_archived = nullptr;
5617 if (!quiet_rotation) {
5618 ret = notification_thread_command_session_rotation_ongoing(
5619 the_notification_thread_handle, session->id, ongoing_rotation_chunk_id);
5620 if (ret != LTTNG_OK) {
5621 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5622 session->name);
5623 cmd_ret = (lttng_error_code) ret;
5624 }
5625 }
5626
5627 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5628 session->name,
5629 ongoing_rotation_chunk_id);
5630 end:
5631 lttng_trace_chunk_put(new_trace_chunk);
5632 lttng_trace_chunk_put(chunk_being_archived);
5633 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5634 return ret;
5635 error:
5636 if (session_reset_rotation_state(*session, LTTNG_ROTATION_STATE_ERROR)) {
5637 ERR("Failed to reset rotation state of session \"%s\"", session->name);
5638 }
5639 goto end;
5640 }
5641
5642 /*
5643 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5644 *
5645 * Check if the session has finished its rotation.
5646 *
5647 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5648 */
5649 int cmd_rotate_get_info(struct ltt_session *session,
5650 struct lttng_rotation_get_info_return *info_return,
5651 uint64_t rotation_id)
5652 {
5653 enum lttng_error_code cmd_ret = LTTNG_OK;
5654 enum lttng_rotation_state rotation_state;
5655
5656 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64,
5657 session->name,
5658 session->most_recent_chunk_id.value);
5659
5660 if (session->chunk_being_archived) {
5661 enum lttng_trace_chunk_status chunk_status;
5662 uint64_t chunk_id;
5663
5664 chunk_status = lttng_trace_chunk_get_id(session->chunk_being_archived, &chunk_id);
5665 LTTNG_ASSERT(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5666
5667 rotation_state = rotation_id == chunk_id ? LTTNG_ROTATION_STATE_ONGOING :
5668 LTTNG_ROTATION_STATE_EXPIRED;
5669 } else {
5670 if (session->last_archived_chunk_id.is_set &&
5671 rotation_id != session->last_archived_chunk_id.value) {
5672 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5673 } else {
5674 rotation_state = session->rotation_state;
5675 }
5676 }
5677
5678 switch (rotation_state) {
5679 case LTTNG_ROTATION_STATE_NO_ROTATION:
5680 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5681 session->name);
5682 goto end;
5683 case LTTNG_ROTATION_STATE_EXPIRED:
5684 DBG("Reporting that the rotation state of rotation id %" PRIu64
5685 " of session \"%s\" has expired",
5686 rotation_id,
5687 session->name);
5688 break;
5689 case LTTNG_ROTATION_STATE_ONGOING:
5690 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5691 rotation_id,
5692 session->name);
5693 break;
5694 case LTTNG_ROTATION_STATE_COMPLETED:
5695 {
5696 int fmt_ret;
5697 char *chunk_path;
5698 char *current_tracing_path_reply;
5699 size_t current_tracing_path_reply_len;
5700
5701 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5702 rotation_id,
5703 session->name);
5704
5705 switch (session_get_consumer_destination_type(session)) {
5706 case CONSUMER_DST_LOCAL:
5707 current_tracing_path_reply = info_return->location.local.absolute_path;
5708 current_tracing_path_reply_len =
5709 sizeof(info_return->location.local.absolute_path);
5710 info_return->location_type =
5711 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5712 fmt_ret = asprintf(&chunk_path,
5713 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5714 session_get_base_path(session),
5715 session->last_archived_chunk_name);
5716 if (fmt_ret == -1) {
5717 PERROR("Failed to format the path of the last archived trace chunk");
5718 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5719 cmd_ret = LTTNG_ERR_UNK;
5720 goto end;
5721 }
5722 break;
5723 case CONSUMER_DST_NET:
5724 {
5725 uint16_t ctrl_port, data_port;
5726
5727 current_tracing_path_reply = info_return->location.relay.relative_path;
5728 current_tracing_path_reply_len =
5729 sizeof(info_return->location.relay.relative_path);
5730 /* Currently the only supported relay protocol. */
5731 info_return->location.relay.protocol =
5732 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5733
5734 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5735 session_get_net_consumer_hostname(session),
5736 sizeof(info_return->location.relay.host));
5737 if (fmt_ret) {
5738 ERR("Failed to copy host name to rotate_get_info reply");
5739 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5740 cmd_ret = LTTNG_ERR_SET_URL;
5741 goto end;
5742 }
5743
5744 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5745 info_return->location.relay.ports.control = ctrl_port;
5746 info_return->location.relay.ports.data = data_port;
5747 info_return->location_type =
5748 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5749 chunk_path = strdup(session->last_chunk_path);
5750 if (!chunk_path) {
5751 ERR("Failed to allocate the path of the last archived trace chunk");
5752 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5753 cmd_ret = LTTNG_ERR_UNK;
5754 goto end;
5755 }
5756 break;
5757 }
5758 default:
5759 abort();
5760 }
5761
5762 fmt_ret = lttng_strncpy(
5763 current_tracing_path_reply, chunk_path, current_tracing_path_reply_len);
5764 free(chunk_path);
5765 if (fmt_ret) {
5766 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5767 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5768 cmd_ret = LTTNG_ERR_UNK;
5769 goto end;
5770 }
5771
5772 break;
5773 }
5774 case LTTNG_ROTATION_STATE_ERROR:
5775 DBG("Reporting that an error occurred during rotation %" PRIu64
5776 " of session \"%s\"",
5777 rotation_id,
5778 session->name);
5779 break;
5780 default:
5781 abort();
5782 }
5783
5784 cmd_ret = LTTNG_OK;
5785 end:
5786 info_return->status = (int32_t) rotation_state;
5787 return cmd_ret;
5788 }
5789
5790 /*
5791 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5792 *
5793 * Configure the automatic rotation parameters.
5794 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5795 * 'activate' to false means deactivate the rotation schedule and validate that
5796 * 'new_value' has the same value as the currently active value.
5797 *
5798 * Return LTTNG_OK on success or else a positive LTTNG_ERR code.
5799 */
5800 int cmd_rotation_set_schedule(struct ltt_session *session,
5801 bool activate,
5802 enum lttng_rotation_schedule_type schedule_type,
5803 uint64_t new_value)
5804 {
5805 int ret;
5806 uint64_t *parameter_value;
5807
5808 LTTNG_ASSERT(session);
5809
5810 DBG("Cmd rotate set schedule session %s", session->name);
5811
5812 if (session->live_timer || !session->output_traces) {
5813 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5814 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5815 goto end;
5816 }
5817
5818 switch (schedule_type) {
5819 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5820 parameter_value = &session->rotate_size;
5821 break;
5822 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5823 parameter_value = &session->rotate_timer_period;
5824 if (new_value >= UINT_MAX) {
5825 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64
5826 " > %u (UINT_MAX)",
5827 new_value,
5828 UINT_MAX);
5829 ret = LTTNG_ERR_INVALID;
5830 goto end;
5831 }
5832 break;
5833 default:
5834 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5835 ret = LTTNG_ERR_INVALID;
5836 goto end;
5837 }
5838
5839 /* Improper use of the API. */
5840 if (new_value == -1ULL) {
5841 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5842 ret = LTTNG_ERR_INVALID;
5843 goto end;
5844 }
5845
5846 /*
5847 * As indicated in struct ltt_session's comments, a value of == 0 means
5848 * this schedule rotation type is not in use.
5849 *
5850 * Reject the command if we were asked to activate a schedule that was
5851 * already active.
5852 */
5853 if (activate && *parameter_value != 0) {
5854 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5855 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5856 goto end;
5857 }
5858
5859 /*
5860 * Reject the command if we were asked to deactivate a schedule that was
5861 * not active.
5862 */
5863 if (!activate && *parameter_value == 0) {
5864 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5865 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5866 goto end;
5867 }
5868
5869 /*
5870 * Reject the command if we were asked to deactivate a schedule that
5871 * doesn't exist.
5872 */
5873 if (!activate && *parameter_value != new_value) {
5874 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5875 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5876 goto end;
5877 }
5878
5879 *parameter_value = activate ? new_value : 0;
5880
5881 switch (schedule_type) {
5882 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5883 if (activate && session->active) {
5884 /*
5885 * Only start the timer if the session is active,
5886 * otherwise it will be started when the session starts.
5887 */
5888 ret = timer_session_rotation_schedule_timer_start(session, new_value);
5889 if (ret) {
5890 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5891 ret = LTTNG_ERR_UNK;
5892 goto end;
5893 }
5894 } else {
5895 ret = timer_session_rotation_schedule_timer_stop(session);
5896 if (ret) {
5897 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5898 ret = LTTNG_ERR_UNK;
5899 goto end;
5900 }
5901 }
5902 break;
5903 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5904 if (activate) {
5905 try {
5906 the_rotation_thread_handle->subscribe_session_consumed_size_rotation(
5907 *session, new_value);
5908 } catch (const std::exception& e) {
5909 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command: %s",
5910 e.what());
5911 ret = LTTNG_ERR_UNK;
5912 goto end;
5913 }
5914 } else {
5915 try {
5916 the_rotation_thread_handle
5917 ->unsubscribe_session_consumed_size_rotation(*session);
5918 } catch (const std::exception& e) {
5919 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command: %s",
5920 e.what());
5921 ret = LTTNG_ERR_UNK;
5922 goto end;
5923 }
5924 }
5925 break;
5926 default:
5927 /* Would have been caught before. */
5928 abort();
5929 }
5930
5931 ret = LTTNG_OK;
5932
5933 goto end;
5934
5935 end:
5936 return ret;
5937 }
5938
5939 /* Wait for a given path to be removed before continuing. */
5940 static enum lttng_error_code wait_on_path(void *path_data)
5941 {
5942 const char *shm_path = (const char *) path_data;
5943
5944 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5945 shm_path);
5946 while (true) {
5947 int ret;
5948 struct stat st;
5949
5950 ret = stat(shm_path, &st);
5951 if (ret) {
5952 if (errno != ENOENT) {
5953 PERROR("stat() returned an error while checking for the existence of the shm path");
5954 } else {
5955 DBG("shm path no longer exists, completing the destruction of session");
5956 }
5957 break;
5958 } else {
5959 if (!S_ISDIR(st.st_mode)) {
5960 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5961 shm_path);
5962 break;
5963 }
5964 }
5965 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5966 }
5967 return LTTNG_OK;
5968 }
5969
5970 /*
5971 * Returns a pointer to a handler to run on completion of a command.
5972 * Returns NULL if no handler has to be run for the last command executed.
5973 */
5974 const struct cmd_completion_handler *cmd_pop_completion_handler()
5975 {
5976 struct cmd_completion_handler *handler = current_completion_handler;
5977
5978 current_completion_handler = nullptr;
5979 return handler;
5980 }
5981
5982 /*
5983 * Init command subsystem.
5984 */
5985 void cmd_init()
5986 {
5987 /*
5988 * Set network sequence index to 1 for streams to match a relayd
5989 * socket on the consumer side.
5990 */
5991 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5992 relayd_net_seq_idx = 1;
5993 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5994
5995 DBG("Command subsystem initialized");
5996 }
LTTng 2.0 tools and control repository
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