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Fix: honor base path for network URIs
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License, version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <inttypes.h>
22 #include <urcu/list.h>
23 #include <urcu/uatomic.h>
24 #include <sys/stat.h>
25 #include <stdio.h>
26
27 #include <common/defaults.h>
28 #include <common/common.h>
29 #include <common/sessiond-comm/sessiond-comm.h>
30 #include <common/relayd/relayd.h>
31 #include <common/utils.h>
32 #include <common/compat/string.h>
33 #include <common/kernel-ctl/kernel-ctl.h>
34 #include <common/dynamic-buffer.h>
35 #include <common/buffer-view.h>
36 #include <common/trace-chunk.h>
37 #include <lttng/location-internal.h>
38 #include <lttng/trigger/trigger-internal.h>
39 #include <lttng/condition/condition.h>
40 #include <lttng/action/action.h>
41 #include <lttng/channel.h>
42 #include <lttng/channel-internal.h>
43 #include <lttng/rotate-internal.h>
44 #include <lttng/location-internal.h>
45 #include <lttng/session-internal.h>
46 #include <lttng/userspace-probe-internal.h>
47 #include <lttng/session-descriptor-internal.h>
48 #include <common/string-utils/string-utils.h>
49
50 #include "channel.h"
51 #include "consumer.h"
52 #include "event.h"
53 #include "health-sessiond.h"
54 #include "kernel.h"
55 #include "kernel-consumer.h"
56 #include "lttng-sessiond.h"
57 #include "utils.h"
58 #include "lttng-syscall.h"
59 #include "agent.h"
60 #include "buffer-registry.h"
61 #include "notification-thread.h"
62 #include "notification-thread-commands.h"
63 #include "rotate.h"
64 #include "rotation-thread.h"
65 #include "timer.h"
66 #include "agent-thread.h"
67
68 #include "cmd.h"
69
70 /* Sleep for 100ms between each check for the shm path's deletion. */
71 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
72
73 struct cmd_destroy_session_reply_context {
74 int reply_sock_fd;
75 bool implicit_rotation_on_destroy;
76 };
77
78 static enum lttng_error_code wait_on_path(void *path);
79
80 /*
81 * Command completion handler that is used by the destroy command
82 * when a session that has a non-default shm_path is being destroyed.
83 *
84 * See comment in cmd_destroy_session() for the rationale.
85 */
86 static struct destroy_completion_handler {
87 struct cmd_completion_handler handler;
88 char shm_path[member_sizeof(struct ltt_session, shm_path)];
89 } destroy_completion_handler = {
90 .handler = {
91 .run = wait_on_path,
92 .data = destroy_completion_handler.shm_path
93 },
94 .shm_path = { 0 },
95 };
96
97 static struct cmd_completion_handler *current_completion_handler;
98
99 /*
100 * Used to keep a unique index for each relayd socket created where this value
101 * is associated with streams on the consumer so it can match the right relayd
102 * to send to. It must be accessed with the relayd_net_seq_idx_lock
103 * held.
104 */
105 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
106 static uint64_t relayd_net_seq_idx;
107
108 static int validate_ust_event_name(const char *);
109 static int cmd_enable_event_internal(struct ltt_session *session,
110 struct lttng_domain *domain,
111 char *channel_name, struct lttng_event *event,
112 char *filter_expression,
113 struct lttng_filter_bytecode *filter,
114 struct lttng_event_exclusion *exclusion,
115 int wpipe);
116
117 /*
118 * Create a session path used by list_lttng_sessions for the case that the
119 * session consumer is on the network.
120 */
121 static int build_network_session_path(char *dst, size_t size,
122 struct ltt_session *session)
123 {
124 int ret, kdata_port, udata_port;
125 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
126 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
127
128 assert(session);
129 assert(dst);
130
131 memset(tmp_urls, 0, sizeof(tmp_urls));
132 memset(tmp_uurl, 0, sizeof(tmp_uurl));
133
134 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
135
136 if (session->kernel_session && session->kernel_session->consumer) {
137 kuri = &session->kernel_session->consumer->dst.net.control;
138 kdata_port = session->kernel_session->consumer->dst.net.data.port;
139 }
140
141 if (session->ust_session && session->ust_session->consumer) {
142 uuri = &session->ust_session->consumer->dst.net.control;
143 udata_port = session->ust_session->consumer->dst.net.data.port;
144 }
145
146 if (uuri == NULL && kuri == NULL) {
147 uri = &session->consumer->dst.net.control;
148 kdata_port = session->consumer->dst.net.data.port;
149 } else if (kuri && uuri) {
150 ret = uri_compare(kuri, uuri);
151 if (ret) {
152 /* Not Equal */
153 uri = kuri;
154 /* Build uuri URL string */
155 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
156 if (ret < 0) {
157 goto error;
158 }
159 } else {
160 uri = kuri;
161 }
162 } else if (kuri && uuri == NULL) {
163 uri = kuri;
164 } else if (uuri && kuri == NULL) {
165 uri = uuri;
166 }
167
168 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
169 if (ret < 0) {
170 goto error;
171 }
172
173 /*
174 * Do we have a UST url set. If yes, this means we have both kernel and UST
175 * to print.
176 */
177 if (*tmp_uurl != '\0') {
178 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
179 tmp_urls, kdata_port, tmp_uurl, udata_port);
180 } else {
181 int dport;
182 if (kuri || (!kuri && !uuri)) {
183 dport = kdata_port;
184 } else {
185 /* No kernel URI, use the UST port. */
186 dport = udata_port;
187 }
188 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
189 }
190
191 error:
192 return ret;
193 }
194
195 /*
196 * Get run-time attributes if the session has been started (discarded events,
197 * lost packets).
198 */
199 static int get_kernel_runtime_stats(struct ltt_session *session,
200 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
201 uint64_t *lost_packets)
202 {
203 int ret;
204
205 if (!session->has_been_started) {
206 ret = 0;
207 *discarded_events = 0;
208 *lost_packets = 0;
209 goto end;
210 }
211
212 ret = consumer_get_discarded_events(session->id, kchan->key,
213 session->kernel_session->consumer,
214 discarded_events);
215 if (ret < 0) {
216 goto end;
217 }
218
219 ret = consumer_get_lost_packets(session->id, kchan->key,
220 session->kernel_session->consumer,
221 lost_packets);
222 if (ret < 0) {
223 goto end;
224 }
225
226 end:
227 return ret;
228 }
229
230 /*
231 * Get run-time attributes if the session has been started (discarded events,
232 * lost packets).
233 */
234 static int get_ust_runtime_stats(struct ltt_session *session,
235 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
236 uint64_t *lost_packets)
237 {
238 int ret;
239 struct ltt_ust_session *usess;
240
241 if (!discarded_events || !lost_packets) {
242 ret = -1;
243 goto end;
244 }
245
246 usess = session->ust_session;
247 assert(discarded_events);
248 assert(lost_packets);
249
250 if (!usess || !session->has_been_started) {
251 *discarded_events = 0;
252 *lost_packets = 0;
253 ret = 0;
254 goto end;
255 }
256
257 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
258 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
259 &usess->buffer_reg_uid_list,
260 usess->consumer, uchan->id,
261 uchan->attr.overwrite,
262 discarded_events,
263 lost_packets);
264 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
265 ret = ust_app_pid_get_channel_runtime_stats(usess,
266 uchan, usess->consumer,
267 uchan->attr.overwrite,
268 discarded_events,
269 lost_packets);
270 if (ret < 0) {
271 goto end;
272 }
273 *discarded_events += uchan->per_pid_closed_app_discarded;
274 *lost_packets += uchan->per_pid_closed_app_lost;
275 } else {
276 ERR("Unsupported buffer type");
277 assert(0);
278 ret = -1;
279 goto end;
280 }
281
282 end:
283 return ret;
284 }
285
286 /*
287 * Fill lttng_channel array of all channels.
288 */
289 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
290 struct ltt_session *session, struct lttng_channel *channels,
291 struct lttng_channel_extended *chan_exts)
292 {
293 int i = 0, ret = 0;
294 struct ltt_kernel_channel *kchan;
295
296 DBG("Listing channels for session %s", session->name);
297
298 switch (domain) {
299 case LTTNG_DOMAIN_KERNEL:
300 /* Kernel channels */
301 if (session->kernel_session != NULL) {
302 cds_list_for_each_entry(kchan,
303 &session->kernel_session->channel_list.head, list) {
304 uint64_t discarded_events, lost_packets;
305 struct lttng_channel_extended *extended;
306
307 extended = (struct lttng_channel_extended *)
308 kchan->channel->attr.extended.ptr;
309
310 ret = get_kernel_runtime_stats(session, kchan,
311 &discarded_events, &lost_packets);
312 if (ret < 0) {
313 goto end;
314 }
315 /* Copy lttng_channel struct to array */
316 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
317 channels[i].enabled = kchan->enabled;
318 chan_exts[i].discarded_events =
319 discarded_events;
320 chan_exts[i].lost_packets = lost_packets;
321 chan_exts[i].monitor_timer_interval =
322 extended->monitor_timer_interval;
323 chan_exts[i].blocking_timeout = 0;
324 i++;
325 }
326 }
327 break;
328 case LTTNG_DOMAIN_UST:
329 {
330 struct lttng_ht_iter iter;
331 struct ltt_ust_channel *uchan;
332
333 rcu_read_lock();
334 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
335 &iter.iter, uchan, node.node) {
336 uint64_t discarded_events = 0, lost_packets = 0;
337
338 if (lttng_strncpy(channels[i].name, uchan->name,
339 LTTNG_SYMBOL_NAME_LEN)) {
340 break;
341 }
342 channels[i].attr.overwrite = uchan->attr.overwrite;
343 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
344 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
345 channels[i].attr.switch_timer_interval =
346 uchan->attr.switch_timer_interval;
347 channels[i].attr.read_timer_interval =
348 uchan->attr.read_timer_interval;
349 channels[i].enabled = uchan->enabled;
350 channels[i].attr.tracefile_size = uchan->tracefile_size;
351 channels[i].attr.tracefile_count = uchan->tracefile_count;
352
353 /*
354 * Map enum lttng_ust_output to enum lttng_event_output.
355 */
356 switch (uchan->attr.output) {
357 case LTTNG_UST_MMAP:
358 channels[i].attr.output = LTTNG_EVENT_MMAP;
359 break;
360 default:
361 /*
362 * LTTNG_UST_MMAP is the only supported UST
363 * output mode.
364 */
365 assert(0);
366 break;
367 }
368
369 chan_exts[i].monitor_timer_interval =
370 uchan->monitor_timer_interval;
371 chan_exts[i].blocking_timeout =
372 uchan->attr.u.s.blocking_timeout;
373
374 ret = get_ust_runtime_stats(session, uchan,
375 &discarded_events, &lost_packets);
376 if (ret < 0) {
377 break;
378 }
379 chan_exts[i].discarded_events = discarded_events;
380 chan_exts[i].lost_packets = lost_packets;
381 i++;
382 }
383 rcu_read_unlock();
384 break;
385 }
386 default:
387 break;
388 }
389
390 end:
391 if (ret < 0) {
392 return -LTTNG_ERR_FATAL;
393 } else {
394 return LTTNG_OK;
395 }
396 }
397
398 static int increment_extended_len(const char *filter_expression,
399 struct lttng_event_exclusion *exclusion,
400 const struct lttng_userspace_probe_location *probe_location,
401 size_t *extended_len)
402 {
403 int ret = 0;
404
405 *extended_len += sizeof(struct lttcomm_event_extended_header);
406
407 if (filter_expression) {
408 *extended_len += strlen(filter_expression) + 1;
409 }
410
411 if (exclusion) {
412 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
413 }
414
415 if (probe_location) {
416 ret = lttng_userspace_probe_location_serialize(probe_location,
417 NULL, NULL);
418 if (ret < 0) {
419 goto end;
420 }
421 *extended_len += ret;
422 }
423 ret = 0;
424 end:
425 return ret;
426 }
427
428 static int append_extended_info(const char *filter_expression,
429 struct lttng_event_exclusion *exclusion,
430 struct lttng_userspace_probe_location *probe_location,
431 void **extended_at)
432 {
433 int ret = 0;
434 size_t filter_len = 0;
435 size_t nb_exclusions = 0;
436 size_t userspace_probe_location_len = 0;
437 struct lttng_dynamic_buffer location_buffer;
438 struct lttcomm_event_extended_header extended_header;
439
440 if (filter_expression) {
441 filter_len = strlen(filter_expression) + 1;
442 }
443
444 if (exclusion) {
445 nb_exclusions = exclusion->count;
446 }
447
448 if (probe_location) {
449 lttng_dynamic_buffer_init(&location_buffer);
450 ret = lttng_userspace_probe_location_serialize(probe_location,
451 &location_buffer, NULL);
452 if (ret < 0) {
453 ret = -1;
454 goto end;
455 }
456 userspace_probe_location_len = location_buffer.size;
457 }
458
459 /* Set header fields */
460 extended_header.filter_len = filter_len;
461 extended_header.nb_exclusions = nb_exclusions;
462 extended_header.userspace_probe_location_len = userspace_probe_location_len;
463
464 /* Copy header */
465 memcpy(*extended_at, &extended_header, sizeof(extended_header));
466 *extended_at += sizeof(extended_header);
467
468 /* Copy filter string */
469 if (filter_expression) {
470 memcpy(*extended_at, filter_expression, filter_len);
471 *extended_at += filter_len;
472 }
473
474 /* Copy exclusion names */
475 if (exclusion) {
476 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
477
478 memcpy(*extended_at, &exclusion->names, len);
479 *extended_at += len;
480 }
481
482 if (probe_location) {
483 memcpy(*extended_at, location_buffer.data, location_buffer.size);
484 *extended_at += location_buffer.size;
485 lttng_dynamic_buffer_reset(&location_buffer);
486 }
487 ret = 0;
488 end:
489 return ret;
490 }
491
492 /*
493 * Create a list of agent domain events.
494 *
495 * Return number of events in list on success or else a negative value.
496 */
497 static int list_lttng_agent_events(struct agent *agt,
498 struct lttng_event **events, size_t *total_size)
499 {
500 int i = 0, ret = 0;
501 unsigned int nb_event = 0;
502 struct agent_event *event;
503 struct lttng_event *tmp_events = NULL;
504 struct lttng_ht_iter iter;
505 size_t extended_len = 0;
506 void *extended_at;
507
508 assert(agt);
509 assert(events);
510
511 DBG3("Listing agent events");
512
513 rcu_read_lock();
514 nb_event = lttng_ht_get_count(agt->events);
515 rcu_read_unlock();
516 if (nb_event == 0) {
517 ret = nb_event;
518 *total_size = 0;
519 goto error;
520 }
521
522 /* Compute required extended infos size */
523 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
524
525 /*
526 * This is only valid because the commands which add events are
527 * processed in the same thread as the listing.
528 */
529 rcu_read_lock();
530 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
531 ret = increment_extended_len(event->filter_expression, NULL, NULL,
532 &extended_len);
533 if (ret) {
534 DBG("Error computing the length of extended info message");
535 ret = -LTTNG_ERR_FATAL;
536 goto error;
537 }
538 }
539 rcu_read_unlock();
540
541 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
542 tmp_events = zmalloc(*total_size);
543 if (!tmp_events) {
544 PERROR("zmalloc agent events session");
545 ret = -LTTNG_ERR_FATAL;
546 goto error;
547 }
548
549 extended_at = ((uint8_t *) tmp_events) +
550 nb_event * sizeof(struct lttng_event);
551
552 rcu_read_lock();
553 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
554 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
555 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
556 tmp_events[i].enabled = event->enabled;
557 tmp_events[i].loglevel = event->loglevel_value;
558 tmp_events[i].loglevel_type = event->loglevel_type;
559 i++;
560
561 /* Append extended info */
562 ret = append_extended_info(event->filter_expression, NULL, NULL,
563 &extended_at);
564 if (ret) {
565 DBG("Error appending extended info message");
566 ret = -LTTNG_ERR_FATAL;
567 goto error;
568 }
569 }
570
571 *events = tmp_events;
572 ret = nb_event;
573 assert(nb_event == i);
574
575 end:
576 rcu_read_unlock();
577 return ret;
578 error:
579 free(tmp_events);
580 goto end;
581 }
582
583 /*
584 * Create a list of ust global domain events.
585 */
586 static int list_lttng_ust_global_events(char *channel_name,
587 struct ltt_ust_domain_global *ust_global,
588 struct lttng_event **events, size_t *total_size)
589 {
590 int i = 0, ret = 0;
591 unsigned int nb_event = 0;
592 struct lttng_ht_iter iter;
593 struct lttng_ht_node_str *node;
594 struct ltt_ust_channel *uchan;
595 struct ltt_ust_event *uevent;
596 struct lttng_event *tmp;
597 size_t extended_len = 0;
598 void *extended_at;
599
600 DBG("Listing UST global events for channel %s", channel_name);
601
602 rcu_read_lock();
603
604 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
605 node = lttng_ht_iter_get_node_str(&iter);
606 if (node == NULL) {
607 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
608 goto end;
609 }
610
611 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
612
613 nb_event = lttng_ht_get_count(uchan->events);
614 if (nb_event == 0) {
615 ret = nb_event;
616 *total_size = 0;
617 goto end;
618 }
619
620 DBG3("Listing UST global %d events", nb_event);
621
622 /* Compute required extended infos size */
623 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
624 if (uevent->internal) {
625 nb_event--;
626 continue;
627 }
628
629 ret = increment_extended_len(uevent->filter_expression,
630 uevent->exclusion, NULL, &extended_len);
631 if (ret) {
632 DBG("Error computing the length of extended info message");
633 ret = -LTTNG_ERR_FATAL;
634 goto end;
635 }
636 }
637 if (nb_event == 0) {
638 /* All events are internal, skip. */
639 ret = 0;
640 *total_size = 0;
641 goto end;
642 }
643
644 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
645 tmp = zmalloc(*total_size);
646 if (tmp == NULL) {
647 ret = -LTTNG_ERR_FATAL;
648 goto end;
649 }
650
651 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
652
653 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
654 if (uevent->internal) {
655 /* This event should remain hidden from clients */
656 continue;
657 }
658 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
659 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
660 tmp[i].enabled = uevent->enabled;
661
662 switch (uevent->attr.instrumentation) {
663 case LTTNG_UST_TRACEPOINT:
664 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
665 break;
666 case LTTNG_UST_PROBE:
667 tmp[i].type = LTTNG_EVENT_PROBE;
668 break;
669 case LTTNG_UST_FUNCTION:
670 tmp[i].type = LTTNG_EVENT_FUNCTION;
671 break;
672 }
673
674 tmp[i].loglevel = uevent->attr.loglevel;
675 switch (uevent->attr.loglevel_type) {
676 case LTTNG_UST_LOGLEVEL_ALL:
677 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
678 break;
679 case LTTNG_UST_LOGLEVEL_RANGE:
680 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
681 break;
682 case LTTNG_UST_LOGLEVEL_SINGLE:
683 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
684 break;
685 }
686 if (uevent->filter) {
687 tmp[i].filter = 1;
688 }
689 if (uevent->exclusion) {
690 tmp[i].exclusion = 1;
691 }
692 i++;
693
694 /* Append extended info */
695 ret = append_extended_info(uevent->filter_expression,
696 uevent->exclusion, NULL, &extended_at);
697 if (ret) {
698 DBG("Error appending extended info message");
699 ret = -LTTNG_ERR_FATAL;
700 goto end;
701 }
702 }
703
704 ret = nb_event;
705 *events = tmp;
706 end:
707 rcu_read_unlock();
708 return ret;
709 }
710
711 /*
712 * Fill lttng_event array of all kernel events in the channel.
713 */
714 static int list_lttng_kernel_events(char *channel_name,
715 struct ltt_kernel_session *kernel_session,
716 struct lttng_event **events, size_t *total_size)
717 {
718 int i = 0, ret;
719 unsigned int nb_event;
720 struct ltt_kernel_event *event;
721 struct ltt_kernel_channel *kchan;
722 size_t extended_len = 0;
723 void *extended_at;
724
725 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
726 if (kchan == NULL) {
727 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
728 goto error;
729 }
730
731 nb_event = kchan->event_count;
732
733 DBG("Listing events for channel %s", kchan->channel->name);
734
735 if (nb_event == 0) {
736 *total_size = 0;
737 *events = NULL;
738 goto end;
739 }
740
741 /* Compute required extended infos size */
742 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
743 ret = increment_extended_len(event->filter_expression, NULL,
744 event->userspace_probe_location,
745 &extended_len);
746 if (ret) {
747 DBG("Error computing the length of extended info message");
748 ret = -LTTNG_ERR_FATAL;
749 goto error;
750 }
751 }
752
753 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
754 *events = zmalloc(*total_size);
755 if (*events == NULL) {
756 ret = -LTTNG_ERR_FATAL;
757 goto error;
758 }
759
760 extended_at = ((void *) *events) +
761 nb_event * sizeof(struct lttng_event);
762
763 /* Kernel channels */
764 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
765 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
766 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
767 (*events)[i].enabled = event->enabled;
768 (*events)[i].filter =
769 (unsigned char) !!event->filter_expression;
770
771 switch (event->event->instrumentation) {
772 case LTTNG_KERNEL_TRACEPOINT:
773 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
774 break;
775 case LTTNG_KERNEL_KRETPROBE:
776 (*events)[i].type = LTTNG_EVENT_FUNCTION;
777 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
778 sizeof(struct lttng_kernel_kprobe));
779 break;
780 case LTTNG_KERNEL_KPROBE:
781 (*events)[i].type = LTTNG_EVENT_PROBE;
782 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
783 sizeof(struct lttng_kernel_kprobe));
784 break;
785 case LTTNG_KERNEL_UPROBE:
786 (*events)[i].type = LTTNG_EVENT_USERSPACE_PROBE;
787 break;
788 case LTTNG_KERNEL_FUNCTION:
789 (*events)[i].type = LTTNG_EVENT_FUNCTION;
790 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
791 sizeof(struct lttng_kernel_function));
792 break;
793 case LTTNG_KERNEL_NOOP:
794 (*events)[i].type = LTTNG_EVENT_NOOP;
795 break;
796 case LTTNG_KERNEL_SYSCALL:
797 (*events)[i].type = LTTNG_EVENT_SYSCALL;
798 break;
799 case LTTNG_KERNEL_ALL:
800 /* fall-through. */
801 default:
802 assert(0);
803 break;
804 }
805 i++;
806
807 /* Append extended info */
808 ret = append_extended_info(event->filter_expression, NULL,
809 event->userspace_probe_location, &extended_at);
810 if (ret) {
811 DBG("Error appending extended info message");
812 ret = -LTTNG_ERR_FATAL;
813 goto error;
814 }
815 }
816
817 end:
818 return nb_event;
819
820 error:
821 /* Negate the error code to differentiate the size from an error */
822 return -ret;
823 }
824
825 /*
826 * Add URI so the consumer output object. Set the correct path depending on the
827 * domain adding the default trace directory.
828 */
829 static enum lttng_error_code add_uri_to_consumer(
830 const struct ltt_session *session,
831 struct consumer_output *consumer,
832 struct lttng_uri *uri, enum lttng_domain_type domain)
833 {
834 int ret;
835 enum lttng_error_code ret_code = LTTNG_OK;
836
837 assert(uri);
838
839 if (consumer == NULL) {
840 DBG("No consumer detected. Don't add URI. Stopping.");
841 ret_code = LTTNG_ERR_NO_CONSUMER;
842 goto error;
843 }
844
845 switch (domain) {
846 case LTTNG_DOMAIN_KERNEL:
847 ret = lttng_strncpy(consumer->domain_subdir,
848 DEFAULT_KERNEL_TRACE_DIR,
849 sizeof(consumer->domain_subdir));
850 break;
851 case LTTNG_DOMAIN_UST:
852 ret = lttng_strncpy(consumer->domain_subdir,
853 DEFAULT_UST_TRACE_DIR,
854 sizeof(consumer->domain_subdir));
855 break;
856 default:
857 /*
858 * This case is possible is we try to add the URI to the global
859 * tracing session consumer object which in this case there is
860 * no subdir.
861 */
862 memset(consumer->domain_subdir, 0,
863 sizeof(consumer->domain_subdir));
864 ret = 0;
865 }
866 if (ret) {
867 ERR("Failed to initialize consumer output domain subdirectory");
868 ret_code = LTTNG_ERR_FATAL;
869 goto error;
870 }
871
872 switch (uri->dtype) {
873 case LTTNG_DST_IPV4:
874 case LTTNG_DST_IPV6:
875 DBG2("Setting network URI to consumer");
876
877 if (consumer->type == CONSUMER_DST_NET) {
878 if ((uri->stype == LTTNG_STREAM_CONTROL &&
879 consumer->dst.net.control_isset) ||
880 (uri->stype == LTTNG_STREAM_DATA &&
881 consumer->dst.net.data_isset)) {
882 ret_code = LTTNG_ERR_URL_EXIST;
883 goto error;
884 }
885 } else {
886 memset(&consumer->dst, 0, sizeof(consumer->dst));
887 }
888
889 /* Set URI into consumer output object */
890 ret = consumer_set_network_uri(session, consumer, uri);
891 if (ret < 0) {
892 ret_code = -ret;
893 goto error;
894 } else if (ret == 1) {
895 /*
896 * URI was the same in the consumer so we do not append the subdir
897 * again so to not duplicate output dir.
898 */
899 ret_code = LTTNG_OK;
900 goto error;
901 }
902 break;
903 case LTTNG_DST_PATH:
904 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
905 ret_code = LTTNG_ERR_INVALID;
906 goto error;
907 }
908 DBG2("Setting trace directory path from URI to %s",
909 uri->dst.path);
910 memset(&consumer->dst, 0, sizeof(consumer->dst));
911
912 ret = lttng_strncpy(consumer->dst.session_root_path,
913 uri->dst.path,
914 sizeof(consumer->dst.session_root_path));
915 consumer->type = CONSUMER_DST_LOCAL;
916 break;
917 }
918
919 ret_code = LTTNG_OK;
920 error:
921 return ret_code;
922 }
923
924 /*
925 * Init tracing by creating trace directory and sending fds kernel consumer.
926 */
927 static int init_kernel_tracing(struct ltt_kernel_session *session)
928 {
929 int ret = 0;
930 struct lttng_ht_iter iter;
931 struct consumer_socket *socket;
932
933 assert(session);
934
935 rcu_read_lock();
936
937 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
938 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
939 socket, node.node) {
940 pthread_mutex_lock(socket->lock);
941 ret = kernel_consumer_send_session(socket, session);
942 pthread_mutex_unlock(socket->lock);
943 if (ret < 0) {
944 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
945 goto error;
946 }
947 }
948 }
949
950 error:
951 rcu_read_unlock();
952 return ret;
953 }
954
955 /*
956 * Create a socket to the relayd using the URI.
957 *
958 * On success, the relayd_sock pointer is set to the created socket.
959 * Else, it remains untouched and an LTTng error code is returned.
960 */
961 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
962 struct lttcomm_relayd_sock **relayd_sock,
963 struct consumer_output *consumer)
964 {
965 int ret;
966 enum lttng_error_code status = LTTNG_OK;
967 struct lttcomm_relayd_sock *rsock;
968
969 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
970 RELAYD_VERSION_COMM_MINOR);
971 if (!rsock) {
972 status = LTTNG_ERR_FATAL;
973 goto error;
974 }
975
976 /*
977 * Connect to relayd so we can proceed with a session creation. This call
978 * can possibly block for an arbitrary amount of time to set the health
979 * state to be in poll execution.
980 */
981 health_poll_entry();
982 ret = relayd_connect(rsock);
983 health_poll_exit();
984 if (ret < 0) {
985 ERR("Unable to reach lttng-relayd");
986 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
987 goto free_sock;
988 }
989
990 /* Create socket for control stream. */
991 if (uri->stype == LTTNG_STREAM_CONTROL) {
992 DBG3("Creating relayd stream socket from URI");
993
994 /* Check relayd version */
995 ret = relayd_version_check(rsock);
996 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
997 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
998 goto close_sock;
999 } else if (ret < 0) {
1000 ERR("Unable to reach lttng-relayd");
1001 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1002 goto close_sock;
1003 }
1004 consumer->relay_major_version = rsock->major;
1005 consumer->relay_minor_version = rsock->minor;
1006 } else if (uri->stype == LTTNG_STREAM_DATA) {
1007 DBG3("Creating relayd data socket from URI");
1008 } else {
1009 /* Command is not valid */
1010 ERR("Relayd invalid stream type: %d", uri->stype);
1011 status = LTTNG_ERR_INVALID;
1012 goto close_sock;
1013 }
1014
1015 *relayd_sock = rsock;
1016
1017 return status;
1018
1019 close_sock:
1020 /* The returned value is not useful since we are on an error path. */
1021 (void) relayd_close(rsock);
1022 free_sock:
1023 free(rsock);
1024 error:
1025 return status;
1026 }
1027
1028 /*
1029 * Connect to the relayd using URI and send the socket to the right consumer.
1030 *
1031 * The consumer socket lock must be held by the caller.
1032 *
1033 * Returns LTTNG_OK on success or an LTTng error code on failure.
1034 */
1035 static enum lttng_error_code send_consumer_relayd_socket(
1036 unsigned int session_id,
1037 struct lttng_uri *relayd_uri,
1038 struct consumer_output *consumer,
1039 struct consumer_socket *consumer_sock,
1040 const char *session_name, const char *hostname,
1041 const char *base_path, int session_live_timer,
1042 const uint64_t *current_chunk_id,
1043 time_t session_creation_time)
1044 {
1045 int ret;
1046 struct lttcomm_relayd_sock *rsock = NULL;
1047 enum lttng_error_code status;
1048
1049 /* Connect to relayd and make version check if uri is the control. */
1050 status = create_connect_relayd(relayd_uri, &rsock, consumer);
1051 if (status != LTTNG_OK) {
1052 goto relayd_comm_error;
1053 }
1054 assert(rsock);
1055
1056 /* Set the network sequence index if not set. */
1057 if (consumer->net_seq_index == (uint64_t) -1ULL) {
1058 pthread_mutex_lock(&relayd_net_seq_idx_lock);
1059 /*
1060 * Increment net_seq_idx because we are about to transfer the
1061 * new relayd socket to the consumer.
1062 * Assign unique key so the consumer can match streams.
1063 */
1064 consumer->net_seq_index = ++relayd_net_seq_idx;
1065 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
1066 }
1067
1068 /* Send relayd socket to consumer. */
1069 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
1070 relayd_uri->stype, session_id,
1071 session_name, hostname, base_path,
1072 session_live_timer, current_chunk_id,
1073 session_creation_time);
1074 if (ret < 0) {
1075 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
1076 goto close_sock;
1077 }
1078
1079 /* Flag that the corresponding socket was sent. */
1080 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
1081 consumer_sock->control_sock_sent = 1;
1082 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
1083 consumer_sock->data_sock_sent = 1;
1084 }
1085
1086 /*
1087 * Close socket which was dup on the consumer side. The session daemon does
1088 * NOT keep track of the relayd socket(s) once transfer to the consumer.
1089 */
1090
1091 close_sock:
1092 if (status != LTTNG_OK) {
1093 /*
1094 * The consumer output for this session should not be used anymore
1095 * since the relayd connection failed thus making any tracing or/and
1096 * streaming not usable.
1097 */
1098 consumer->enabled = 0;
1099 }
1100 (void) relayd_close(rsock);
1101 free(rsock);
1102
1103 relayd_comm_error:
1104 return status;
1105 }
1106
1107 /*
1108 * Send both relayd sockets to a specific consumer and domain. This is a
1109 * helper function to facilitate sending the information to the consumer for a
1110 * session.
1111 *
1112 * The consumer socket lock must be held by the caller.
1113 *
1114 * Returns LTTNG_OK, or an LTTng error code on failure.
1115 */
1116 static enum lttng_error_code send_consumer_relayd_sockets(
1117 enum lttng_domain_type domain,
1118 unsigned int session_id, struct consumer_output *consumer,
1119 struct consumer_socket *sock, const char *session_name,
1120 const char *hostname, const char *base_path, int session_live_timer,
1121 const uint64_t *current_chunk_id, time_t session_creation_time)
1122 {
1123 enum lttng_error_code status = LTTNG_OK;
1124
1125 assert(consumer);
1126 assert(sock);
1127
1128 /* Sending control relayd socket. */
1129 if (!sock->control_sock_sent) {
1130 status = send_consumer_relayd_socket(session_id,
1131 &consumer->dst.net.control, consumer, sock,
1132 session_name, hostname, base_path, session_live_timer,
1133 current_chunk_id, session_creation_time);
1134 if (status != LTTNG_OK) {
1135 goto error;
1136 }
1137 }
1138
1139 /* Sending data relayd socket. */
1140 if (!sock->data_sock_sent) {
1141 status = send_consumer_relayd_socket(session_id,
1142 &consumer->dst.net.data, consumer, sock,
1143 session_name, hostname, base_path, session_live_timer,
1144 current_chunk_id, session_creation_time);
1145 if (status != LTTNG_OK) {
1146 goto error;
1147 }
1148 }
1149
1150 error:
1151 return status;
1152 }
1153
1154 /*
1155 * Setup relayd connections for a tracing session. First creates the socket to
1156 * the relayd and send them to the right domain consumer. Consumer type MUST be
1157 * network.
1158 */
1159 int cmd_setup_relayd(struct ltt_session *session)
1160 {
1161 int ret = LTTNG_OK;
1162 struct ltt_ust_session *usess;
1163 struct ltt_kernel_session *ksess;
1164 struct consumer_socket *socket;
1165 struct lttng_ht_iter iter;
1166 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1167
1168 assert(session);
1169
1170 usess = session->ust_session;
1171 ksess = session->kernel_session;
1172
1173 DBG("Setting relayd for session %s", session->name);
1174
1175 if (session->current_trace_chunk) {
1176 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1177 session->current_trace_chunk, &current_chunk_id.value);
1178
1179 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1180 current_chunk_id.is_set = true;
1181 } else {
1182 ERR("Failed to get current trace chunk id");
1183 ret = LTTNG_ERR_UNK;
1184 goto error;
1185 }
1186 }
1187
1188 rcu_read_lock();
1189
1190 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1191 && usess->consumer->enabled) {
1192 /* For each consumer socket, send relayd sockets */
1193 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1194 socket, node.node) {
1195 pthread_mutex_lock(socket->lock);
1196 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1197 usess->consumer, socket,
1198 session->name, session->hostname,
1199 session->base_path,
1200 session->live_timer,
1201 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1202 session->creation_time);
1203 pthread_mutex_unlock(socket->lock);
1204 if (ret != LTTNG_OK) {
1205 goto error;
1206 }
1207 /* Session is now ready for network streaming. */
1208 session->net_handle = 1;
1209 }
1210 session->consumer->relay_major_version =
1211 usess->consumer->relay_major_version;
1212 session->consumer->relay_minor_version =
1213 usess->consumer->relay_minor_version;
1214 }
1215
1216 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1217 && ksess->consumer->enabled) {
1218 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1219 socket, node.node) {
1220 pthread_mutex_lock(socket->lock);
1221 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1222 ksess->consumer, socket,
1223 session->name, session->hostname,
1224 session->base_path,
1225 session->live_timer,
1226 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1227 session->creation_time);
1228 pthread_mutex_unlock(socket->lock);
1229 if (ret != LTTNG_OK) {
1230 goto error;
1231 }
1232 /* Session is now ready for network streaming. */
1233 session->net_handle = 1;
1234 }
1235 session->consumer->relay_major_version =
1236 ksess->consumer->relay_major_version;
1237 session->consumer->relay_minor_version =
1238 ksess->consumer->relay_minor_version;
1239 }
1240
1241 error:
1242 rcu_read_unlock();
1243 return ret;
1244 }
1245
1246 /*
1247 * Start a kernel session by opening all necessary streams.
1248 */
1249 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1250 {
1251 int ret;
1252 struct ltt_kernel_channel *kchan;
1253
1254 /* Open kernel metadata */
1255 if (ksess->metadata == NULL && ksess->output_traces) {
1256 ret = kernel_open_metadata(ksess);
1257 if (ret < 0) {
1258 ret = LTTNG_ERR_KERN_META_FAIL;
1259 goto error;
1260 }
1261 }
1262
1263 /* Open kernel metadata stream */
1264 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1265 ret = kernel_open_metadata_stream(ksess);
1266 if (ret < 0) {
1267 ERR("Kernel create metadata stream failed");
1268 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1269 goto error;
1270 }
1271 }
1272
1273 /* For each channel */
1274 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1275 if (kchan->stream_count == 0) {
1276 ret = kernel_open_channel_stream(kchan);
1277 if (ret < 0) {
1278 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1279 goto error;
1280 }
1281 /* Update the stream global counter */
1282 ksess->stream_count_global += ret;
1283 }
1284 }
1285
1286 /* Setup kernel consumer socket and send fds to it */
1287 ret = init_kernel_tracing(ksess);
1288 if (ret != 0) {
1289 ret = LTTNG_ERR_KERN_START_FAIL;
1290 goto error;
1291 }
1292
1293 /* This start the kernel tracing */
1294 ret = kernel_start_session(ksess);
1295 if (ret < 0) {
1296 ret = LTTNG_ERR_KERN_START_FAIL;
1297 goto error;
1298 }
1299
1300 /* Quiescent wait after starting trace */
1301 kernel_wait_quiescent(wpipe);
1302
1303 ksess->active = 1;
1304
1305 ret = LTTNG_OK;
1306
1307 error:
1308 return ret;
1309 }
1310
1311 /*
1312 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1313 */
1314 int cmd_disable_channel(struct ltt_session *session,
1315 enum lttng_domain_type domain, char *channel_name)
1316 {
1317 int ret;
1318 struct ltt_ust_session *usess;
1319
1320 usess = session->ust_session;
1321
1322 rcu_read_lock();
1323
1324 switch (domain) {
1325 case LTTNG_DOMAIN_KERNEL:
1326 {
1327 ret = channel_kernel_disable(session->kernel_session,
1328 channel_name);
1329 if (ret != LTTNG_OK) {
1330 goto error;
1331 }
1332
1333 kernel_wait_quiescent(kernel_tracer_fd);
1334 break;
1335 }
1336 case LTTNG_DOMAIN_UST:
1337 {
1338 struct ltt_ust_channel *uchan;
1339 struct lttng_ht *chan_ht;
1340
1341 chan_ht = usess->domain_global.channels;
1342
1343 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1344 if (uchan == NULL) {
1345 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1346 goto error;
1347 }
1348
1349 ret = channel_ust_disable(usess, uchan);
1350 if (ret != LTTNG_OK) {
1351 goto error;
1352 }
1353 break;
1354 }
1355 default:
1356 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1357 goto error;
1358 }
1359
1360 ret = LTTNG_OK;
1361
1362 error:
1363 rcu_read_unlock();
1364 return ret;
1365 }
1366
1367 /*
1368 * Command LTTNG_TRACK_PID processed by the client thread.
1369 *
1370 * Called with session lock held.
1371 */
1372 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1373 int pid)
1374 {
1375 int ret;
1376
1377 rcu_read_lock();
1378
1379 switch (domain) {
1380 case LTTNG_DOMAIN_KERNEL:
1381 {
1382 struct ltt_kernel_session *ksess;
1383
1384 ksess = session->kernel_session;
1385
1386 ret = kernel_track_pid(ksess, pid);
1387 if (ret != LTTNG_OK) {
1388 goto error;
1389 }
1390
1391 kernel_wait_quiescent(kernel_tracer_fd);
1392 break;
1393 }
1394 case LTTNG_DOMAIN_UST:
1395 {
1396 struct ltt_ust_session *usess;
1397
1398 usess = session->ust_session;
1399
1400 ret = trace_ust_track_pid(usess, pid);
1401 if (ret != LTTNG_OK) {
1402 goto error;
1403 }
1404 break;
1405 }
1406 default:
1407 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1408 goto error;
1409 }
1410
1411 ret = LTTNG_OK;
1412
1413 error:
1414 rcu_read_unlock();
1415 return ret;
1416 }
1417
1418 /*
1419 * Command LTTNG_UNTRACK_PID processed by the client thread.
1420 *
1421 * Called with session lock held.
1422 */
1423 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1424 int pid)
1425 {
1426 int ret;
1427
1428 rcu_read_lock();
1429
1430 switch (domain) {
1431 case LTTNG_DOMAIN_KERNEL:
1432 {
1433 struct ltt_kernel_session *ksess;
1434
1435 ksess = session->kernel_session;
1436
1437 ret = kernel_untrack_pid(ksess, pid);
1438 if (ret != LTTNG_OK) {
1439 goto error;
1440 }
1441
1442 kernel_wait_quiescent(kernel_tracer_fd);
1443 break;
1444 }
1445 case LTTNG_DOMAIN_UST:
1446 {
1447 struct ltt_ust_session *usess;
1448
1449 usess = session->ust_session;
1450
1451 ret = trace_ust_untrack_pid(usess, pid);
1452 if (ret != LTTNG_OK) {
1453 goto error;
1454 }
1455 break;
1456 }
1457 default:
1458 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1459 goto error;
1460 }
1461
1462 ret = LTTNG_OK;
1463
1464 error:
1465 rcu_read_unlock();
1466 return ret;
1467 }
1468
1469 /*
1470 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1471 *
1472 * The wpipe arguments is used as a notifier for the kernel thread.
1473 */
1474 int cmd_enable_channel(struct ltt_session *session,
1475 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1476 {
1477 int ret;
1478 struct ltt_ust_session *usess = session->ust_session;
1479 struct lttng_ht *chan_ht;
1480 size_t len;
1481
1482 assert(session);
1483 assert(attr);
1484 assert(domain);
1485
1486 len = lttng_strnlen(attr->name, sizeof(attr->name));
1487
1488 /* Validate channel name */
1489 if (attr->name[0] == '.' ||
1490 memchr(attr->name, '/', len) != NULL) {
1491 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1492 goto end;
1493 }
1494
1495 DBG("Enabling channel %s for session %s", attr->name, session->name);
1496
1497 rcu_read_lock();
1498
1499 /*
1500 * Don't try to enable a channel if the session has been started at
1501 * some point in time before. The tracer does not allow it.
1502 */
1503 if (session->has_been_started) {
1504 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1505 goto error;
1506 }
1507
1508 /*
1509 * If the session is a live session, remove the switch timer, the
1510 * live timer does the same thing but sends also synchronisation
1511 * beacons for inactive streams.
1512 */
1513 if (session->live_timer > 0) {
1514 attr->attr.live_timer_interval = session->live_timer;
1515 attr->attr.switch_timer_interval = 0;
1516 }
1517
1518 /* Check for feature support */
1519 switch (domain->type) {
1520 case LTTNG_DOMAIN_KERNEL:
1521 {
1522 if (kernel_supports_ring_buffer_snapshot_sample_positions(kernel_tracer_fd) != 1) {
1523 /* Sampling position of buffer is not supported */
1524 WARN("Kernel tracer does not support buffer monitoring. "
1525 "Setting the monitor interval timer to 0 "
1526 "(disabled) for channel '%s' of session '%s'",
1527 attr-> name, session->name);
1528 lttng_channel_set_monitor_timer_interval(attr, 0);
1529 }
1530 break;
1531 }
1532 case LTTNG_DOMAIN_UST:
1533 break;
1534 case LTTNG_DOMAIN_JUL:
1535 case LTTNG_DOMAIN_LOG4J:
1536 case LTTNG_DOMAIN_PYTHON:
1537 if (!agent_tracing_is_enabled()) {
1538 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1539 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1540 goto error;
1541 }
1542 break;
1543 default:
1544 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1545 goto error;
1546 }
1547
1548 switch (domain->type) {
1549 case LTTNG_DOMAIN_KERNEL:
1550 {
1551 struct ltt_kernel_channel *kchan;
1552
1553 kchan = trace_kernel_get_channel_by_name(attr->name,
1554 session->kernel_session);
1555 if (kchan == NULL) {
1556 if (session->snapshot.nb_output > 0 ||
1557 session->snapshot_mode) {
1558 /* Enforce mmap output for snapshot sessions. */
1559 attr->attr.output = LTTNG_EVENT_MMAP;
1560 }
1561 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1562 if (attr->name[0] != '\0') {
1563 session->kernel_session->has_non_default_channel = 1;
1564 }
1565 } else {
1566 ret = channel_kernel_enable(session->kernel_session, kchan);
1567 }
1568
1569 if (ret != LTTNG_OK) {
1570 goto error;
1571 }
1572
1573 kernel_wait_quiescent(kernel_tracer_fd);
1574 break;
1575 }
1576 case LTTNG_DOMAIN_UST:
1577 case LTTNG_DOMAIN_JUL:
1578 case LTTNG_DOMAIN_LOG4J:
1579 case LTTNG_DOMAIN_PYTHON:
1580 {
1581 struct ltt_ust_channel *uchan;
1582
1583 /*
1584 * FIXME
1585 *
1586 * Current agent implementation limitations force us to allow
1587 * only one channel at once in "agent" subdomains. Each
1588 * subdomain has a default channel name which must be strictly
1589 * adhered to.
1590 */
1591 if (domain->type == LTTNG_DOMAIN_JUL) {
1592 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1593 LTTNG_SYMBOL_NAME_LEN)) {
1594 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1595 goto error;
1596 }
1597 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1598 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1599 LTTNG_SYMBOL_NAME_LEN)) {
1600 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1601 goto error;
1602 }
1603 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1604 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1605 LTTNG_SYMBOL_NAME_LEN)) {
1606 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1607 goto error;
1608 }
1609 }
1610
1611 chan_ht = usess->domain_global.channels;
1612
1613 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1614 if (uchan == NULL) {
1615 ret = channel_ust_create(usess, attr, domain->buf_type);
1616 if (attr->name[0] != '\0') {
1617 usess->has_non_default_channel = 1;
1618 }
1619 } else {
1620 ret = channel_ust_enable(usess, uchan);
1621 }
1622 break;
1623 }
1624 default:
1625 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1626 goto error;
1627 }
1628
1629 if (ret == LTTNG_OK && attr->attr.output != LTTNG_EVENT_MMAP) {
1630 session->has_non_mmap_channel = true;
1631 }
1632 error:
1633 rcu_read_unlock();
1634 end:
1635 return ret;
1636 }
1637
1638 /*
1639 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1640 */
1641 int cmd_disable_event(struct ltt_session *session,
1642 enum lttng_domain_type domain, char *channel_name,
1643 struct lttng_event *event)
1644 {
1645 int ret;
1646 char *event_name;
1647
1648 DBG("Disable event command for event \'%s\'", event->name);
1649
1650 event_name = event->name;
1651
1652 /* Error out on unhandled search criteria */
1653 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1654 || event->pid || event->filter || event->exclusion) {
1655 ret = LTTNG_ERR_UNK;
1656 goto error;
1657 }
1658
1659 rcu_read_lock();
1660
1661 switch (domain) {
1662 case LTTNG_DOMAIN_KERNEL:
1663 {
1664 struct ltt_kernel_channel *kchan;
1665 struct ltt_kernel_session *ksess;
1666
1667 ksess = session->kernel_session;
1668
1669 /*
1670 * If a non-default channel has been created in the
1671 * session, explicitely require that -c chan_name needs
1672 * to be provided.
1673 */
1674 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1675 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1676 goto error_unlock;
1677 }
1678
1679 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1680 if (kchan == NULL) {
1681 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1682 goto error_unlock;
1683 }
1684
1685 switch (event->type) {
1686 case LTTNG_EVENT_ALL:
1687 case LTTNG_EVENT_TRACEPOINT:
1688 case LTTNG_EVENT_SYSCALL:
1689 case LTTNG_EVENT_PROBE:
1690 case LTTNG_EVENT_FUNCTION:
1691 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1692 if (event_name[0] == '\0') {
1693 ret = event_kernel_disable_event(kchan,
1694 NULL, event->type);
1695 } else {
1696 ret = event_kernel_disable_event(kchan,
1697 event_name, event->type);
1698 }
1699 if (ret != LTTNG_OK) {
1700 goto error_unlock;
1701 }
1702 break;
1703 default:
1704 ret = LTTNG_ERR_UNK;
1705 goto error_unlock;
1706 }
1707
1708 kernel_wait_quiescent(kernel_tracer_fd);
1709 break;
1710 }
1711 case LTTNG_DOMAIN_UST:
1712 {
1713 struct ltt_ust_channel *uchan;
1714 struct ltt_ust_session *usess;
1715
1716 usess = session->ust_session;
1717
1718 if (validate_ust_event_name(event_name)) {
1719 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1720 goto error_unlock;
1721 }
1722
1723 /*
1724 * If a non-default channel has been created in the
1725 * session, explicitly require that -c chan_name needs
1726 * to be provided.
1727 */
1728 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1729 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1730 goto error_unlock;
1731 }
1732
1733 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1734 channel_name);
1735 if (uchan == NULL) {
1736 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1737 goto error_unlock;
1738 }
1739
1740 switch (event->type) {
1741 case LTTNG_EVENT_ALL:
1742 /*
1743 * An empty event name means that everything
1744 * should be disabled.
1745 */
1746 if (event->name[0] == '\0') {
1747 ret = event_ust_disable_all_tracepoints(usess, uchan);
1748 } else {
1749 ret = event_ust_disable_tracepoint(usess, uchan,
1750 event_name);
1751 }
1752 if (ret != LTTNG_OK) {
1753 goto error_unlock;
1754 }
1755 break;
1756 default:
1757 ret = LTTNG_ERR_UNK;
1758 goto error_unlock;
1759 }
1760
1761 DBG3("Disable UST event %s in channel %s completed", event_name,
1762 channel_name);
1763 break;
1764 }
1765 case LTTNG_DOMAIN_LOG4J:
1766 case LTTNG_DOMAIN_JUL:
1767 case LTTNG_DOMAIN_PYTHON:
1768 {
1769 struct agent *agt;
1770 struct ltt_ust_session *usess = session->ust_session;
1771
1772 assert(usess);
1773
1774 switch (event->type) {
1775 case LTTNG_EVENT_ALL:
1776 break;
1777 default:
1778 ret = LTTNG_ERR_UNK;
1779 goto error_unlock;
1780 }
1781
1782 agt = trace_ust_find_agent(usess, domain);
1783 if (!agt) {
1784 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1785 goto error_unlock;
1786 }
1787 /*
1788 * An empty event name means that everything
1789 * should be disabled.
1790 */
1791 if (event->name[0] == '\0') {
1792 ret = event_agent_disable_all(usess, agt);
1793 } else {
1794 ret = event_agent_disable(usess, agt, event_name);
1795 }
1796 if (ret != LTTNG_OK) {
1797 goto error_unlock;
1798 }
1799
1800 break;
1801 }
1802 default:
1803 ret = LTTNG_ERR_UND;
1804 goto error_unlock;
1805 }
1806
1807 ret = LTTNG_OK;
1808
1809 error_unlock:
1810 rcu_read_unlock();
1811 error:
1812 return ret;
1813 }
1814
1815 /*
1816 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1817 */
1818 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1819 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1820 {
1821 int ret, chan_kern_created = 0, chan_ust_created = 0;
1822 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1823
1824 /*
1825 * Don't try to add a context if the session has been started at
1826 * some point in time before. The tracer does not allow it and would
1827 * result in a corrupted trace.
1828 */
1829 if (session->has_been_started) {
1830 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1831 goto end;
1832 }
1833
1834 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1835 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1836 app_ctx_name = ctx->u.app_ctx.ctx_name;
1837 }
1838
1839 switch (domain) {
1840 case LTTNG_DOMAIN_KERNEL:
1841 assert(session->kernel_session);
1842
1843 if (session->kernel_session->channel_count == 0) {
1844 /* Create default channel */
1845 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1846 if (ret != LTTNG_OK) {
1847 goto error;
1848 }
1849 chan_kern_created = 1;
1850 }
1851 /* Add kernel context to kernel tracer */
1852 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1853 if (ret != LTTNG_OK) {
1854 goto error;
1855 }
1856 break;
1857 case LTTNG_DOMAIN_JUL:
1858 case LTTNG_DOMAIN_LOG4J:
1859 {
1860 /*
1861 * Validate channel name.
1862 * If no channel name is given and the domain is JUL or LOG4J,
1863 * set it to the appropriate domain-specific channel name. If
1864 * a name is provided but does not match the expexted channel
1865 * name, return an error.
1866 */
1867 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1868 strcmp(channel_name,
1869 DEFAULT_JUL_CHANNEL_NAME)) {
1870 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1871 goto error;
1872 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1873 strcmp(channel_name,
1874 DEFAULT_LOG4J_CHANNEL_NAME)) {
1875 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1876 goto error;
1877 }
1878 /* break is _not_ missing here. */
1879 }
1880 case LTTNG_DOMAIN_UST:
1881 {
1882 struct ltt_ust_session *usess = session->ust_session;
1883 unsigned int chan_count;
1884
1885 assert(usess);
1886
1887 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1888 if (chan_count == 0) {
1889 struct lttng_channel *attr;
1890 /* Create default channel */
1891 attr = channel_new_default_attr(domain, usess->buffer_type);
1892 if (attr == NULL) {
1893 ret = LTTNG_ERR_FATAL;
1894 goto error;
1895 }
1896
1897 ret = channel_ust_create(usess, attr, usess->buffer_type);
1898 if (ret != LTTNG_OK) {
1899 free(attr);
1900 goto error;
1901 }
1902 channel_attr_destroy(attr);
1903 chan_ust_created = 1;
1904 }
1905
1906 ret = context_ust_add(usess, domain, ctx, channel_name);
1907 free(app_ctx_provider_name);
1908 free(app_ctx_name);
1909 app_ctx_name = NULL;
1910 app_ctx_provider_name = NULL;
1911 if (ret != LTTNG_OK) {
1912 goto error;
1913 }
1914 break;
1915 }
1916 default:
1917 ret = LTTNG_ERR_UND;
1918 goto error;
1919 }
1920
1921 ret = LTTNG_OK;
1922 goto end;
1923
1924 error:
1925 if (chan_kern_created) {
1926 struct ltt_kernel_channel *kchan =
1927 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1928 session->kernel_session);
1929 /* Created previously, this should NOT fail. */
1930 assert(kchan);
1931 kernel_destroy_channel(kchan);
1932 }
1933
1934 if (chan_ust_created) {
1935 struct ltt_ust_channel *uchan =
1936 trace_ust_find_channel_by_name(
1937 session->ust_session->domain_global.channels,
1938 DEFAULT_CHANNEL_NAME);
1939 /* Created previously, this should NOT fail. */
1940 assert(uchan);
1941 /* Remove from the channel list of the session. */
1942 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1943 uchan);
1944 trace_ust_destroy_channel(uchan);
1945 }
1946 end:
1947 free(app_ctx_provider_name);
1948 free(app_ctx_name);
1949 return ret;
1950 }
1951
1952 static inline bool name_starts_with(const char *name, const char *prefix)
1953 {
1954 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1955
1956 return !strncmp(name, prefix, max_cmp_len);
1957 }
1958
1959 /* Perform userspace-specific event name validation */
1960 static int validate_ust_event_name(const char *name)
1961 {
1962 int ret = 0;
1963
1964 if (!name) {
1965 ret = -1;
1966 goto end;
1967 }
1968
1969 /*
1970 * Check name against all internal UST event component namespaces used
1971 * by the agents.
1972 */
1973 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1974 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1975 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1976 ret = -1;
1977 }
1978
1979 end:
1980 return ret;
1981 }
1982
1983 /*
1984 * Internal version of cmd_enable_event() with a supplemental
1985 * "internal_event" flag which is used to enable internal events which should
1986 * be hidden from clients. Such events are used in the agent implementation to
1987 * enable the events through which all "agent" events are funeled.
1988 */
1989 static int _cmd_enable_event(struct ltt_session *session,
1990 struct lttng_domain *domain,
1991 char *channel_name, struct lttng_event *event,
1992 char *filter_expression,
1993 struct lttng_filter_bytecode *filter,
1994 struct lttng_event_exclusion *exclusion,
1995 int wpipe, bool internal_event)
1996 {
1997 int ret = 0, channel_created = 0;
1998 struct lttng_channel *attr = NULL;
1999
2000 assert(session);
2001 assert(event);
2002 assert(channel_name);
2003
2004 /* If we have a filter, we must have its filter expression */
2005 assert(!(!!filter_expression ^ !!filter));
2006
2007 /* Normalize event name as a globbing pattern */
2008 strutils_normalize_star_glob_pattern(event->name);
2009
2010 /* Normalize exclusion names as globbing patterns */
2011 if (exclusion) {
2012 size_t i;
2013
2014 for (i = 0; i < exclusion->count; i++) {
2015 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2016
2017 strutils_normalize_star_glob_pattern(name);
2018 }
2019 }
2020
2021 DBG("Enable event command for event \'%s\'", event->name);
2022
2023 rcu_read_lock();
2024
2025 switch (domain->type) {
2026 case LTTNG_DOMAIN_KERNEL:
2027 {
2028 struct ltt_kernel_channel *kchan;
2029
2030 /*
2031 * If a non-default channel has been created in the
2032 * session, explicitely require that -c chan_name needs
2033 * to be provided.
2034 */
2035 if (session->kernel_session->has_non_default_channel
2036 && channel_name[0] == '\0') {
2037 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2038 goto error;
2039 }
2040
2041 kchan = trace_kernel_get_channel_by_name(channel_name,
2042 session->kernel_session);
2043 if (kchan == NULL) {
2044 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2045 LTTNG_BUFFER_GLOBAL);
2046 if (attr == NULL) {
2047 ret = LTTNG_ERR_FATAL;
2048 goto error;
2049 }
2050 if (lttng_strncpy(attr->name, channel_name,
2051 sizeof(attr->name))) {
2052 ret = LTTNG_ERR_INVALID;
2053 goto error;
2054 }
2055
2056 ret = cmd_enable_channel(session, domain, attr, wpipe);
2057 if (ret != LTTNG_OK) {
2058 goto error;
2059 }
2060 channel_created = 1;
2061 }
2062
2063 /* Get the newly created kernel channel pointer */
2064 kchan = trace_kernel_get_channel_by_name(channel_name,
2065 session->kernel_session);
2066 if (kchan == NULL) {
2067 /* This sould not happen... */
2068 ret = LTTNG_ERR_FATAL;
2069 goto error;
2070 }
2071
2072 switch (event->type) {
2073 case LTTNG_EVENT_ALL:
2074 {
2075 char *filter_expression_a = NULL;
2076 struct lttng_filter_bytecode *filter_a = NULL;
2077
2078 /*
2079 * We need to duplicate filter_expression and filter,
2080 * because ownership is passed to first enable
2081 * event.
2082 */
2083 if (filter_expression) {
2084 filter_expression_a = strdup(filter_expression);
2085 if (!filter_expression_a) {
2086 ret = LTTNG_ERR_FATAL;
2087 goto error;
2088 }
2089 }
2090 if (filter) {
2091 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2092 if (!filter_a) {
2093 free(filter_expression_a);
2094 ret = LTTNG_ERR_FATAL;
2095 goto error;
2096 }
2097 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2098 }
2099 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2100 ret = event_kernel_enable_event(kchan, event,
2101 filter_expression, filter);
2102 /* We have passed ownership */
2103 filter_expression = NULL;
2104 filter = NULL;
2105 if (ret != LTTNG_OK) {
2106 if (channel_created) {
2107 /* Let's not leak a useless channel. */
2108 kernel_destroy_channel(kchan);
2109 }
2110 free(filter_expression_a);
2111 free(filter_a);
2112 goto error;
2113 }
2114 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2115 ret = event_kernel_enable_event(kchan, event,
2116 filter_expression_a, filter_a);
2117 /* We have passed ownership */
2118 filter_expression_a = NULL;
2119 filter_a = NULL;
2120 if (ret != LTTNG_OK) {
2121 goto error;
2122 }
2123 break;
2124 }
2125 case LTTNG_EVENT_PROBE:
2126 case LTTNG_EVENT_USERSPACE_PROBE:
2127 case LTTNG_EVENT_FUNCTION:
2128 case LTTNG_EVENT_FUNCTION_ENTRY:
2129 case LTTNG_EVENT_TRACEPOINT:
2130 ret = event_kernel_enable_event(kchan, event,
2131 filter_expression, filter);
2132 /* We have passed ownership */
2133 filter_expression = NULL;
2134 filter = NULL;
2135 if (ret != LTTNG_OK) {
2136 if (channel_created) {
2137 /* Let's not leak a useless channel. */
2138 kernel_destroy_channel(kchan);
2139 }
2140 goto error;
2141 }
2142 break;
2143 case LTTNG_EVENT_SYSCALL:
2144 ret = event_kernel_enable_event(kchan, event,
2145 filter_expression, filter);
2146 /* We have passed ownership */
2147 filter_expression = NULL;
2148 filter = NULL;
2149 if (ret != LTTNG_OK) {
2150 goto error;
2151 }
2152 break;
2153 default:
2154 ret = LTTNG_ERR_UNK;
2155 goto error;
2156 }
2157
2158 kernel_wait_quiescent(kernel_tracer_fd);
2159 break;
2160 }
2161 case LTTNG_DOMAIN_UST:
2162 {
2163 struct ltt_ust_channel *uchan;
2164 struct ltt_ust_session *usess = session->ust_session;
2165
2166 assert(usess);
2167
2168 /*
2169 * If a non-default channel has been created in the
2170 * session, explicitely require that -c chan_name needs
2171 * to be provided.
2172 */
2173 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2174 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2175 goto error;
2176 }
2177
2178 /* Get channel from global UST domain */
2179 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2180 channel_name);
2181 if (uchan == NULL) {
2182 /* Create default channel */
2183 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2184 usess->buffer_type);
2185 if (attr == NULL) {
2186 ret = LTTNG_ERR_FATAL;
2187 goto error;
2188 }
2189 if (lttng_strncpy(attr->name, channel_name,
2190 sizeof(attr->name))) {
2191 ret = LTTNG_ERR_INVALID;
2192 goto error;
2193 }
2194
2195 ret = cmd_enable_channel(session, domain, attr, wpipe);
2196 if (ret != LTTNG_OK) {
2197 goto error;
2198 }
2199
2200 /* Get the newly created channel reference back */
2201 uchan = trace_ust_find_channel_by_name(
2202 usess->domain_global.channels, channel_name);
2203 assert(uchan);
2204 }
2205
2206 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2207 /*
2208 * Don't allow users to add UST events to channels which
2209 * are assigned to a userspace subdomain (JUL, Log4J,
2210 * Python, etc.).
2211 */
2212 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2213 goto error;
2214 }
2215
2216 if (!internal_event) {
2217 /*
2218 * Ensure the event name is not reserved for internal
2219 * use.
2220 */
2221 ret = validate_ust_event_name(event->name);
2222 if (ret) {
2223 WARN("Userspace event name %s failed validation.",
2224 event->name);
2225 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2226 goto error;
2227 }
2228 }
2229
2230 /* At this point, the session and channel exist on the tracer */
2231 ret = event_ust_enable_tracepoint(usess, uchan, event,
2232 filter_expression, filter, exclusion,
2233 internal_event);
2234 /* We have passed ownership */
2235 filter_expression = NULL;
2236 filter = NULL;
2237 exclusion = NULL;
2238 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2239 goto already_enabled;
2240 } else if (ret != LTTNG_OK) {
2241 goto error;
2242 }
2243 break;
2244 }
2245 case LTTNG_DOMAIN_LOG4J:
2246 case LTTNG_DOMAIN_JUL:
2247 case LTTNG_DOMAIN_PYTHON:
2248 {
2249 const char *default_event_name, *default_chan_name;
2250 struct agent *agt;
2251 struct lttng_event uevent;
2252 struct lttng_domain tmp_dom;
2253 struct ltt_ust_session *usess = session->ust_session;
2254
2255 assert(usess);
2256
2257 if (!agent_tracing_is_enabled()) {
2258 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2259 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2260 goto error;
2261 }
2262
2263 agt = trace_ust_find_agent(usess, domain->type);
2264 if (!agt) {
2265 agt = agent_create(domain->type);
2266 if (!agt) {
2267 ret = LTTNG_ERR_NOMEM;
2268 goto error;
2269 }
2270 agent_add(agt, usess->agents);
2271 }
2272
2273 /* Create the default tracepoint. */
2274 memset(&uevent, 0, sizeof(uevent));
2275 uevent.type = LTTNG_EVENT_TRACEPOINT;
2276 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2277 default_event_name = event_get_default_agent_ust_name(
2278 domain->type);
2279 if (!default_event_name) {
2280 ret = LTTNG_ERR_FATAL;
2281 goto error;
2282 }
2283 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2284 uevent.name[sizeof(uevent.name) - 1] = '\0';
2285
2286 /*
2287 * The domain type is changed because we are about to enable the
2288 * default channel and event for the JUL domain that are hardcoded.
2289 * This happens in the UST domain.
2290 */
2291 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2292 tmp_dom.type = LTTNG_DOMAIN_UST;
2293
2294 switch (domain->type) {
2295 case LTTNG_DOMAIN_LOG4J:
2296 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2297 break;
2298 case LTTNG_DOMAIN_JUL:
2299 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2300 break;
2301 case LTTNG_DOMAIN_PYTHON:
2302 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2303 break;
2304 default:
2305 /* The switch/case we are in makes this impossible */
2306 assert(0);
2307 }
2308
2309 {
2310 char *filter_expression_copy = NULL;
2311 struct lttng_filter_bytecode *filter_copy = NULL;
2312
2313 if (filter) {
2314 const size_t filter_size = sizeof(
2315 struct lttng_filter_bytecode)
2316 + filter->len;
2317
2318 filter_copy = zmalloc(filter_size);
2319 if (!filter_copy) {
2320 ret = LTTNG_ERR_NOMEM;
2321 goto error;
2322 }
2323 memcpy(filter_copy, filter, filter_size);
2324
2325 filter_expression_copy =
2326 strdup(filter_expression);
2327 if (!filter_expression) {
2328 ret = LTTNG_ERR_NOMEM;
2329 }
2330
2331 if (!filter_expression_copy || !filter_copy) {
2332 free(filter_expression_copy);
2333 free(filter_copy);
2334 goto error;
2335 }
2336 }
2337
2338 ret = cmd_enable_event_internal(session, &tmp_dom,
2339 (char *) default_chan_name,
2340 &uevent, filter_expression_copy,
2341 filter_copy, NULL, wpipe);
2342 }
2343
2344 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2345 goto already_enabled;
2346 } else if (ret != LTTNG_OK) {
2347 goto error;
2348 }
2349
2350 /* The wild card * means that everything should be enabled. */
2351 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2352 ret = event_agent_enable_all(usess, agt, event, filter,
2353 filter_expression);
2354 } else {
2355 ret = event_agent_enable(usess, agt, event, filter,
2356 filter_expression);
2357 }
2358 filter = NULL;
2359 filter_expression = NULL;
2360 if (ret != LTTNG_OK) {
2361 goto error;
2362 }
2363
2364 break;
2365 }
2366 default:
2367 ret = LTTNG_ERR_UND;
2368 goto error;
2369 }
2370
2371 ret = LTTNG_OK;
2372
2373 already_enabled:
2374 error:
2375 free(filter_expression);
2376 free(filter);
2377 free(exclusion);
2378 channel_attr_destroy(attr);
2379 rcu_read_unlock();
2380 return ret;
2381 }
2382
2383 /*
2384 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2385 * We own filter, exclusion, and filter_expression.
2386 */
2387 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
2388 char *channel_name, struct lttng_event *event,
2389 char *filter_expression,
2390 struct lttng_filter_bytecode *filter,
2391 struct lttng_event_exclusion *exclusion,
2392 int wpipe)
2393 {
2394 return _cmd_enable_event(session, domain, channel_name, event,
2395 filter_expression, filter, exclusion, wpipe, false);
2396 }
2397
2398 /*
2399 * Enable an event which is internal to LTTng. An internal should
2400 * never be made visible to clients and are immune to checks such as
2401 * reserved names.
2402 */
2403 static int cmd_enable_event_internal(struct ltt_session *session,
2404 struct lttng_domain *domain,
2405 char *channel_name, struct lttng_event *event,
2406 char *filter_expression,
2407 struct lttng_filter_bytecode *filter,
2408 struct lttng_event_exclusion *exclusion,
2409 int wpipe)
2410 {
2411 return _cmd_enable_event(session, domain, channel_name, event,
2412 filter_expression, filter, exclusion, wpipe, true);
2413 }
2414
2415 /*
2416 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2417 */
2418 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2419 struct lttng_event **events)
2420 {
2421 int ret;
2422 ssize_t nb_events = 0;
2423
2424 switch (domain) {
2425 case LTTNG_DOMAIN_KERNEL:
2426 nb_events = kernel_list_events(kernel_tracer_fd, events);
2427 if (nb_events < 0) {
2428 ret = LTTNG_ERR_KERN_LIST_FAIL;
2429 goto error;
2430 }
2431 break;
2432 case LTTNG_DOMAIN_UST:
2433 nb_events = ust_app_list_events(events);
2434 if (nb_events < 0) {
2435 ret = LTTNG_ERR_UST_LIST_FAIL;
2436 goto error;
2437 }
2438 break;
2439 case LTTNG_DOMAIN_LOG4J:
2440 case LTTNG_DOMAIN_JUL:
2441 case LTTNG_DOMAIN_PYTHON:
2442 nb_events = agent_list_events(events, domain);
2443 if (nb_events < 0) {
2444 ret = LTTNG_ERR_UST_LIST_FAIL;
2445 goto error;
2446 }
2447 break;
2448 default:
2449 ret = LTTNG_ERR_UND;
2450 goto error;
2451 }
2452
2453 return nb_events;
2454
2455 error:
2456 /* Return negative value to differentiate return code */
2457 return -ret;
2458 }
2459
2460 /*
2461 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2462 */
2463 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2464 struct lttng_event_field **fields)
2465 {
2466 int ret;
2467 ssize_t nb_fields = 0;
2468
2469 switch (domain) {
2470 case LTTNG_DOMAIN_UST:
2471 nb_fields = ust_app_list_event_fields(fields);
2472 if (nb_fields < 0) {
2473 ret = LTTNG_ERR_UST_LIST_FAIL;
2474 goto error;
2475 }
2476 break;
2477 case LTTNG_DOMAIN_KERNEL:
2478 default: /* fall-through */
2479 ret = LTTNG_ERR_UND;
2480 goto error;
2481 }
2482
2483 return nb_fields;
2484
2485 error:
2486 /* Return negative value to differentiate return code */
2487 return -ret;
2488 }
2489
2490 ssize_t cmd_list_syscalls(struct lttng_event **events)
2491 {
2492 return syscall_table_list(events);
2493 }
2494
2495 /*
2496 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2497 *
2498 * Called with session lock held.
2499 */
2500 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2501 enum lttng_domain_type domain, int32_t **pids)
2502 {
2503 int ret;
2504 ssize_t nr_pids = 0;
2505
2506 switch (domain) {
2507 case LTTNG_DOMAIN_KERNEL:
2508 {
2509 struct ltt_kernel_session *ksess;
2510
2511 ksess = session->kernel_session;
2512 nr_pids = kernel_list_tracker_pids(ksess, pids);
2513 if (nr_pids < 0) {
2514 ret = LTTNG_ERR_KERN_LIST_FAIL;
2515 goto error;
2516 }
2517 break;
2518 }
2519 case LTTNG_DOMAIN_UST:
2520 {
2521 struct ltt_ust_session *usess;
2522
2523 usess = session->ust_session;
2524 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2525 if (nr_pids < 0) {
2526 ret = LTTNG_ERR_UST_LIST_FAIL;
2527 goto error;
2528 }
2529 break;
2530 }
2531 case LTTNG_DOMAIN_LOG4J:
2532 case LTTNG_DOMAIN_JUL:
2533 case LTTNG_DOMAIN_PYTHON:
2534 default:
2535 ret = LTTNG_ERR_UND;
2536 goto error;
2537 }
2538
2539 return nr_pids;
2540
2541 error:
2542 /* Return negative value to differentiate return code */
2543 return -ret;
2544 }
2545
2546 /*
2547 * Command LTTNG_START_TRACE processed by the client thread.
2548 *
2549 * Called with session mutex held.
2550 */
2551 int cmd_start_trace(struct ltt_session *session)
2552 {
2553 enum lttng_error_code ret;
2554 unsigned long nb_chan = 0;
2555 struct ltt_kernel_session *ksession;
2556 struct ltt_ust_session *usess;
2557
2558 assert(session);
2559
2560 /* Ease our life a bit ;) */
2561 ksession = session->kernel_session;
2562 usess = session->ust_session;
2563
2564 /* Is the session already started? */
2565 if (session->active) {
2566 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2567 goto error;
2568 }
2569
2570 /*
2571 * Starting a session without channel is useless since after that it's not
2572 * possible to enable channel thus inform the client.
2573 */
2574 if (usess && usess->domain_global.channels) {
2575 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2576 }
2577 if (ksession) {
2578 nb_chan += ksession->channel_count;
2579 }
2580 if (!nb_chan) {
2581 ret = LTTNG_ERR_NO_CHANNEL;
2582 goto error;
2583 }
2584
2585 if (session->output_traces && !session->current_trace_chunk &&
2586 session_output_supports_trace_chunks(session)) {
2587 struct lttng_trace_chunk *trace_chunk;
2588
2589 trace_chunk = session_create_new_trace_chunk(
2590 session, NULL, NULL, NULL);
2591 if (!trace_chunk) {
2592 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2593 goto error;
2594 }
2595 assert(!session->current_trace_chunk);
2596 ret = session_set_trace_chunk(session, trace_chunk, NULL);
2597 lttng_trace_chunk_put(trace_chunk);
2598 if (ret) {
2599 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2600 goto error;
2601 }
2602 }
2603
2604 /* Kernel tracing */
2605 if (ksession != NULL) {
2606 DBG("Start kernel tracing session %s", session->name);
2607 ret = start_kernel_session(ksession, kernel_tracer_fd);
2608 if (ret != LTTNG_OK) {
2609 goto error;
2610 }
2611 }
2612
2613 /* Flag session that trace should start automatically */
2614 if (usess) {
2615 int int_ret = ust_app_start_trace_all(usess);
2616
2617 if (int_ret < 0) {
2618 ret = LTTNG_ERR_UST_START_FAIL;
2619 goto error;
2620 }
2621 }
2622
2623 /* Flag this after a successful start. */
2624 session->has_been_started = 1;
2625 session->active = 1;
2626
2627 /*
2628 * Clear the flag that indicates that a rotation was done while the
2629 * session was stopped.
2630 */
2631 session->rotated_after_last_stop = false;
2632
2633 if (session->rotate_timer_period) {
2634 int int_ret = timer_session_rotation_schedule_timer_start(
2635 session, session->rotate_timer_period);
2636
2637 if (int_ret < 0) {
2638 ERR("Failed to enable rotate timer");
2639 ret = LTTNG_ERR_UNK;
2640 goto error;
2641 }
2642 }
2643
2644 ret = LTTNG_OK;
2645
2646 error:
2647 return ret;
2648 }
2649
2650 /*
2651 * Command LTTNG_STOP_TRACE processed by the client thread.
2652 */
2653 int cmd_stop_trace(struct ltt_session *session)
2654 {
2655 int ret;
2656 struct ltt_kernel_channel *kchan;
2657 struct ltt_kernel_session *ksession;
2658 struct ltt_ust_session *usess;
2659 bool error_occurred = false;
2660
2661 assert(session);
2662
2663 DBG("Begin stop session %s (id %" PRIu64 ")", session->name, session->id);
2664 /* Short cut */
2665 ksession = session->kernel_session;
2666 usess = session->ust_session;
2667
2668 /* Session is not active. Skip everythong and inform the client. */
2669 if (!session->active) {
2670 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2671 goto error;
2672 }
2673
2674 /* Kernel tracer */
2675 if (ksession && ksession->active) {
2676 DBG("Stop kernel tracing");
2677
2678 ret = kernel_stop_session(ksession);
2679 if (ret < 0) {
2680 ret = LTTNG_ERR_KERN_STOP_FAIL;
2681 goto error;
2682 }
2683
2684 kernel_wait_quiescent(kernel_tracer_fd);
2685
2686 /* Flush metadata after stopping (if exists) */
2687 if (ksession->metadata_stream_fd >= 0) {
2688 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2689 if (ret < 0) {
2690 ERR("Kernel metadata flush failed");
2691 }
2692 }
2693
2694 /* Flush all buffers after stopping */
2695 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2696 ret = kernel_flush_buffer(kchan);
2697 if (ret < 0) {
2698 ERR("Kernel flush buffer error");
2699 }
2700 }
2701
2702 ksession->active = 0;
2703 DBG("Kernel session stopped %s (id %" PRIu64 ")", session->name,
2704 session->id);
2705 }
2706
2707 if (usess && usess->active) {
2708 ret = ust_app_stop_trace_all(usess);
2709 if (ret < 0) {
2710 ret = LTTNG_ERR_UST_STOP_FAIL;
2711 goto error;
2712 }
2713 }
2714
2715 /* Flag inactive after a successful stop. */
2716 session->active = 0;
2717 ret = !error_occurred ? LTTNG_OK : LTTNG_ERR_UNK;
2718
2719 error:
2720 return ret;
2721 }
2722
2723 /*
2724 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2725 */
2726 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2727 struct lttng_uri *uris)
2728 {
2729 int ret, i;
2730 struct ltt_kernel_session *ksess = session->kernel_session;
2731 struct ltt_ust_session *usess = session->ust_session;
2732
2733 assert(session);
2734 assert(uris);
2735 assert(nb_uri > 0);
2736
2737 /* Can't set consumer URI if the session is active. */
2738 if (session->active) {
2739 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2740 goto error;
2741 }
2742
2743 /* Set the "global" consumer URIs */
2744 for (i = 0; i < nb_uri; i++) {
2745 ret = add_uri_to_consumer(session,
2746 session->consumer,
2747 &uris[i], LTTNG_DOMAIN_NONE);
2748 if (ret != LTTNG_OK) {
2749 goto error;
2750 }
2751 }
2752
2753 /* Set UST session URIs */
2754 if (session->ust_session) {
2755 for (i = 0; i < nb_uri; i++) {
2756 ret = add_uri_to_consumer(session,
2757 session->ust_session->consumer,
2758 &uris[i], LTTNG_DOMAIN_UST);
2759 if (ret != LTTNG_OK) {
2760 goto error;
2761 }
2762 }
2763 }
2764
2765 /* Set kernel session URIs */
2766 if (session->kernel_session) {
2767 for (i = 0; i < nb_uri; i++) {
2768 ret = add_uri_to_consumer(session,
2769 session->kernel_session->consumer,
2770 &uris[i], LTTNG_DOMAIN_KERNEL);
2771 if (ret != LTTNG_OK) {
2772 goto error;
2773 }
2774 }
2775 }
2776
2777 /*
2778 * Make sure to set the session in output mode after we set URI since a
2779 * session can be created without URL (thus flagged in no output mode).
2780 */
2781 session->output_traces = 1;
2782 if (ksess) {
2783 ksess->output_traces = 1;
2784 }
2785
2786 if (usess) {
2787 usess->output_traces = 1;
2788 }
2789
2790 /* All good! */
2791 ret = LTTNG_OK;
2792
2793 error:
2794 return ret;
2795 }
2796
2797 static
2798 enum lttng_error_code set_session_output_from_descriptor(
2799 struct ltt_session *session,
2800 const struct lttng_session_descriptor *descriptor)
2801 {
2802 int ret;
2803 enum lttng_error_code ret_code = LTTNG_OK;
2804 enum lttng_session_descriptor_type session_type =
2805 lttng_session_descriptor_get_type(descriptor);
2806 enum lttng_session_descriptor_output_type output_type =
2807 lttng_session_descriptor_get_output_type(descriptor);
2808 struct lttng_uri uris[2] = {};
2809 size_t uri_count = 0;
2810
2811 switch (output_type) {
2812 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
2813 goto end;
2814 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
2815 lttng_session_descriptor_get_local_output_uri(descriptor,
2816 &uris[0]);
2817 uri_count = 1;
2818 break;
2819 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
2820 lttng_session_descriptor_get_network_output_uris(descriptor,
2821 &uris[0], &uris[1]);
2822 uri_count = 2;
2823 break;
2824 default:
2825 ret_code = LTTNG_ERR_INVALID;
2826 goto end;
2827 }
2828
2829 switch (session_type) {
2830 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2831 {
2832 struct snapshot_output *new_output = NULL;
2833
2834 new_output = snapshot_output_alloc();
2835 if (!new_output) {
2836 ret_code = LTTNG_ERR_NOMEM;
2837 goto end;
2838 }
2839
2840 ret = snapshot_output_init_with_uri(session,
2841 DEFAULT_SNAPSHOT_MAX_SIZE,
2842 NULL, uris, uri_count, session->consumer,
2843 new_output, &session->snapshot);
2844 if (ret < 0) {
2845 ret_code = (ret == -ENOMEM) ?
2846 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
2847 snapshot_output_destroy(new_output);
2848 goto end;
2849 }
2850 snapshot_add_output(&session->snapshot, new_output);
2851 break;
2852 }
2853 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
2854 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
2855 {
2856 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
2857 break;
2858 }
2859 default:
2860 ret_code = LTTNG_ERR_INVALID;
2861 goto end;
2862 }
2863 end:
2864 return ret_code;
2865 }
2866
2867 static
2868 enum lttng_error_code cmd_create_session_from_descriptor(
2869 struct lttng_session_descriptor *descriptor,
2870 const lttng_sock_cred *creds,
2871 const char *home_path)
2872 {
2873 int ret;
2874 enum lttng_error_code ret_code;
2875 const char *session_name;
2876 struct ltt_session *new_session = NULL;
2877 enum lttng_session_descriptor_status descriptor_status;
2878 const char *base_path;
2879
2880 session_lock_list();
2881 if (home_path) {
2882 if (*home_path != '/') {
2883 ERR("Home path provided by client is not absolute");
2884 ret_code = LTTNG_ERR_INVALID;
2885 goto end;
2886 }
2887 }
2888
2889 descriptor_status = lttng_session_descriptor_get_session_name(
2890 descriptor, &session_name);
2891 switch (descriptor_status) {
2892 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
2893 break;
2894 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
2895 session_name = NULL;
2896 break;
2897 default:
2898 ret_code = LTTNG_ERR_INVALID;
2899 goto end;
2900 }
2901 ret = lttng_session_descriptor_get_base_path(descriptor, &base_path);
2902 if (ret) {
2903 ret_code = LTTNG_ERR_INVALID;
2904 goto end;
2905 }
2906 ret_code = session_create(session_name, creds->uid, creds->gid,
2907 base_path, &new_session);
2908 if (ret_code != LTTNG_OK) {
2909 goto end;
2910 }
2911
2912 if (!session_name) {
2913 ret = lttng_session_descriptor_set_session_name(descriptor,
2914 new_session->name);
2915 if (ret) {
2916 ret_code = LTTNG_ERR_SESSION_FAIL;
2917 goto end;
2918 }
2919 }
2920
2921 if (!lttng_session_descriptor_is_output_destination_initialized(
2922 descriptor)) {
2923 /*
2924 * Only include the session's creation time in the output
2925 * destination if the name of the session itself was
2926 * not auto-generated.
2927 */
2928 ret_code = lttng_session_descriptor_set_default_output(
2929 descriptor,
2930 session_name ? &new_session->creation_time : NULL,
2931 home_path);
2932 if (ret_code != LTTNG_OK) {
2933 goto end;
2934 }
2935 } else {
2936 new_session->has_user_specified_directory =
2937 lttng_session_descriptor_has_output_directory(
2938 descriptor);
2939 }
2940
2941 switch (lttng_session_descriptor_get_type(descriptor)) {
2942 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2943 new_session->snapshot_mode = 1;
2944 break;
2945 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
2946 new_session->live_timer =
2947 lttng_session_descriptor_live_get_timer_interval(
2948 descriptor);
2949 break;
2950 default:
2951 break;
2952 }
2953
2954 ret_code = set_session_output_from_descriptor(new_session, descriptor);
2955 if (ret_code != LTTNG_OK) {
2956 goto end;
2957 }
2958 new_session->consumer->enabled = 1;
2959 ret_code = LTTNG_OK;
2960 end:
2961 /* Release reference provided by the session_create function. */
2962 session_put(new_session);
2963 if (ret_code != LTTNG_OK && new_session) {
2964 /* Release the global reference on error. */
2965 session_destroy(new_session);
2966 }
2967 session_unlock_list();
2968 return ret_code;
2969 }
2970
2971 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
2972 struct lttng_session_descriptor **return_descriptor)
2973 {
2974 int ret;
2975 size_t payload_size;
2976 struct lttng_dynamic_buffer payload;
2977 struct lttng_buffer_view home_dir_view;
2978 struct lttng_buffer_view session_descriptor_view;
2979 struct lttng_session_descriptor *session_descriptor = NULL;
2980 enum lttng_error_code ret_code;
2981
2982 lttng_dynamic_buffer_init(&payload);
2983 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
2984 LTTNG_PATH_MAX) {
2985 ret_code = LTTNG_ERR_INVALID;
2986 goto error;
2987 }
2988 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
2989 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
2990 ret_code = LTTNG_ERR_INVALID;
2991 goto error;
2992 }
2993
2994 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
2995 cmd_ctx->lsm->u.create_session.session_descriptor_size;
2996 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
2997 if (ret) {
2998 ret_code = LTTNG_ERR_NOMEM;
2999 goto error;
3000 }
3001
3002 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3003 if (ret <= 0) {
3004 ERR("Reception of session descriptor failed, aborting.");
3005 ret_code = LTTNG_ERR_SESSION_FAIL;
3006 goto error;
3007 }
3008
3009 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3010 &payload,
3011 0,
3012 cmd_ctx->lsm->u.create_session.home_dir_size);
3013 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3014 &payload,
3015 cmd_ctx->lsm->u.create_session.home_dir_size,
3016 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3017
3018 ret = lttng_session_descriptor_create_from_buffer(
3019 &session_descriptor_view, &session_descriptor);
3020 if (ret < 0) {
3021 ERR("Failed to create session descriptor from payload of \"create session\" command");
3022 ret_code = LTTNG_ERR_INVALID;
3023 goto error;
3024 }
3025
3026 /*
3027 * Sets the descriptor's auto-generated properties (name, output) if
3028 * needed.
3029 */
3030 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3031 &cmd_ctx->creds,
3032 home_dir_view.size ? home_dir_view.data : NULL);
3033 if (ret_code != LTTNG_OK) {
3034 goto error;
3035 }
3036
3037 ret_code = LTTNG_OK;
3038 *return_descriptor = session_descriptor;
3039 session_descriptor = NULL;
3040 error:
3041 lttng_dynamic_buffer_reset(&payload);
3042 lttng_session_descriptor_destroy(session_descriptor);
3043 return ret_code;
3044 }
3045
3046 static
3047 void cmd_destroy_session_reply(const struct ltt_session *session,
3048 void *_reply_context)
3049 {
3050 int ret;
3051 ssize_t comm_ret;
3052 const struct cmd_destroy_session_reply_context *reply_context =
3053 _reply_context;
3054 struct lttng_dynamic_buffer payload;
3055 struct lttcomm_session_destroy_command_header cmd_header;
3056 struct lttng_trace_archive_location *location = NULL;
3057 struct lttcomm_lttng_msg llm = {
3058 .cmd_type = LTTNG_DESTROY_SESSION,
3059 .ret_code = LTTNG_OK,
3060 .pid = UINT32_MAX,
3061 .cmd_header_size =
3062 sizeof(struct lttcomm_session_destroy_command_header),
3063 .data_size = 0,
3064 };
3065 size_t payload_size_before_location;
3066
3067 lttng_dynamic_buffer_init(&payload);
3068
3069 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3070 if (ret) {
3071 ERR("Failed to append session destruction message");
3072 goto error;
3073 }
3074
3075 cmd_header.rotation_state =
3076 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3077 session->rotation_state :
3078 LTTNG_ROTATION_STATE_NO_ROTATION);
3079 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3080 sizeof(cmd_header));
3081 if (ret) {
3082 ERR("Failed to append session destruction command header");
3083 goto error;
3084 }
3085
3086 if (!reply_context->implicit_rotation_on_destroy) {
3087 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3088 session->name);
3089 goto send_reply;
3090 }
3091 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3092 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3093 session->name);
3094 goto send_reply;
3095 }
3096
3097 location = session_get_trace_archive_location(session);
3098 if (!location) {
3099 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3100 session->name);
3101 goto error;
3102 }
3103
3104 payload_size_before_location = payload.size;
3105 comm_ret = lttng_trace_archive_location_serialize(location,
3106 &payload);
3107 if (comm_ret < 0) {
3108 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3109 session->name);
3110 goto error;
3111 }
3112 /* Update the message to indicate the location's length. */
3113 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3114 payload.size - payload_size_before_location;
3115 send_reply:
3116 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3117 payload.data, payload.size);
3118 if (comm_ret != (ssize_t) payload.size) {
3119 ERR("Failed to send result of the destruction of session \"%s\" to client",
3120 session->name);
3121 }
3122 error:
3123 ret = close(reply_context->reply_sock_fd);
3124 if (ret) {
3125 PERROR("Failed to close client socket in deferred session destroy reply");
3126 }
3127 lttng_dynamic_buffer_reset(&payload);
3128 free(_reply_context);
3129 }
3130
3131 /*
3132 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3133 *
3134 * Called with session lock held.
3135 */
3136 int cmd_destroy_session(struct ltt_session *session,
3137 struct notification_thread_handle *notification_thread_handle,
3138 int *sock_fd)
3139 {
3140 int ret;
3141 struct cmd_destroy_session_reply_context *reply_context = NULL;
3142
3143 if (sock_fd) {
3144 reply_context = zmalloc(sizeof(*reply_context));
3145 if (!reply_context) {
3146 ret = LTTNG_ERR_NOMEM;
3147 goto end;
3148 }
3149 reply_context->reply_sock_fd = *sock_fd;
3150 }
3151
3152 /* Safety net */
3153 assert(session);
3154
3155 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3156 session->id);
3157 if (session->active) {
3158 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3159 session->name);
3160 ret = cmd_stop_trace(session);
3161 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3162 /* Carry on with the destruction of the session. */
3163 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3164 session->name, lttng_strerror(-ret));
3165 }
3166 }
3167
3168 if (session->rotation_schedule_timer_enabled) {
3169 if (timer_session_rotation_schedule_timer_stop(
3170 session)) {
3171 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3172 session->name);
3173 }
3174 }
3175
3176 if (session->rotate_size) {
3177 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3178 session->rotate_size = 0;
3179 }
3180
3181 if (session->most_recent_chunk_id.is_set &&
3182 session->most_recent_chunk_id.value != 0 &&
3183 session->current_trace_chunk && session->output_traces) {
3184 /*
3185 * Perform a last rotation on destruction if rotations have
3186 * occurred during the session's lifetime.
3187 */
3188 ret = cmd_rotate_session(session, NULL, false);
3189 if (ret != LTTNG_OK) {
3190 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3191 session->name, lttng_strerror(-ret));
3192 }
3193 if (reply_context) {
3194 reply_context->implicit_rotation_on_destroy = true;
3195 }
3196 } else if (session->has_been_started && session->current_trace_chunk &&
3197 session_output_supports_trace_chunks(session)) {
3198 /*
3199 * The user has not triggered a session rotation. However, to
3200 * ensure all data has been consumed, the session is rotated
3201 * to a 'null' trace chunk before it is destroyed.
3202 *
3203 * This is a "quiet" rotation meaning that no notification is
3204 * emitted and no renaming of the current trace chunk takes
3205 * place.
3206 */
3207 ret = cmd_rotate_session(session, NULL, true);
3208 if (ret != LTTNG_OK) {
3209 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3210 session->name, lttng_strerror(-ret));
3211 }
3212 }
3213
3214 if (session->shm_path[0]) {
3215 /*
3216 * When a session is created with an explicit shm_path,
3217 * the consumer daemon will create its shared memory files
3218 * at that location and will *not* unlink them. This is normal
3219 * as the intention of that feature is to make it possible
3220 * to retrieve the content of those files should a crash occur.
3221 *
3222 * To ensure the content of those files can be used, the
3223 * sessiond daemon will replicate the content of the metadata
3224 * cache in a metadata file.
3225 *
3226 * On clean-up, it is expected that the consumer daemon will
3227 * unlink the shared memory files and that the session daemon
3228 * will unlink the metadata file. Then, the session's directory
3229 * in the shm path can be removed.
3230 *
3231 * Unfortunately, a flaw in the design of the sessiond's and
3232 * consumerd's tear down of channels makes it impossible to
3233 * determine when the sessiond _and_ the consumerd have both
3234 * destroyed their representation of a channel. For one, the
3235 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3236 * callbacks in both daemons.
3237 *
3238 * However, it is also impossible for the sessiond to know when
3239 * the consumer daemon is done destroying its channel(s) since
3240 * it occurs as a reaction to the closing of the channel's file
3241 * descriptor. There is no resulting communication initiated
3242 * from the consumerd to the sessiond to confirm that the
3243 * operation is completed (and was successful).
3244 *
3245 * Until this is all fixed, the session daemon checks for the
3246 * removal of the session's shm path which makes it possible
3247 * to safely advertise a session as having been destroyed.
3248 *
3249 * Prior to this fix, it was not possible to reliably save
3250 * a session making use of the --shm-path option, destroy it,
3251 * and load it again. This is because the creation of the
3252 * session would fail upon seeing the session's shm path
3253 * already in existence.
3254 *
3255 * Note that none of the error paths in the check for the
3256 * directory's existence return an error. This is normal
3257 * as there isn't much that can be done. The session will
3258 * be destroyed properly, except that we can't offer the
3259 * guarantee that the same session can be re-created.
3260 */
3261 current_completion_handler = &destroy_completion_handler.handler;
3262 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3263 session->shm_path,
3264 sizeof(destroy_completion_handler.shm_path));
3265 assert(!ret);
3266 }
3267
3268 /*
3269 * The session is destroyed. However, note that the command context
3270 * still holds a reference to the session, thus delaying its destruction
3271 * _at least_ up to the point when that reference is released.
3272 */
3273 session_destroy(session);
3274 if (reply_context) {
3275 ret = session_add_destroy_notifier(session,
3276 cmd_destroy_session_reply,
3277 (void *) reply_context);
3278 if (ret) {
3279 ret = LTTNG_ERR_FATAL;
3280 goto end;
3281 } else {
3282 *sock_fd = -1;
3283 }
3284 }
3285 ret = LTTNG_OK;
3286 end:
3287 return ret;
3288 }
3289
3290 /*
3291 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3292 */
3293 int cmd_register_consumer(struct ltt_session *session,
3294 enum lttng_domain_type domain, const char *sock_path,
3295 struct consumer_data *cdata)
3296 {
3297 int ret, sock;
3298 struct consumer_socket *socket = NULL;
3299
3300 assert(session);
3301 assert(cdata);
3302 assert(sock_path);
3303
3304 switch (domain) {
3305 case LTTNG_DOMAIN_KERNEL:
3306 {
3307 struct ltt_kernel_session *ksess = session->kernel_session;
3308
3309 assert(ksess);
3310
3311 /* Can't register a consumer if there is already one */
3312 if (ksess->consumer_fds_sent != 0) {
3313 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3314 goto error;
3315 }
3316
3317 sock = lttcomm_connect_unix_sock(sock_path);
3318 if (sock < 0) {
3319 ret = LTTNG_ERR_CONNECT_FAIL;
3320 goto error;
3321 }
3322 cdata->cmd_sock = sock;
3323
3324 socket = consumer_allocate_socket(&cdata->cmd_sock);
3325 if (socket == NULL) {
3326 ret = close(sock);
3327 if (ret < 0) {
3328 PERROR("close register consumer");
3329 }
3330 cdata->cmd_sock = -1;
3331 ret = LTTNG_ERR_FATAL;
3332 goto error;
3333 }
3334
3335 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3336 if (socket->lock == NULL) {
3337 PERROR("zmalloc pthread mutex");
3338 ret = LTTNG_ERR_FATAL;
3339 goto error;
3340 }
3341 pthread_mutex_init(socket->lock, NULL);
3342 socket->registered = 1;
3343
3344 rcu_read_lock();
3345 consumer_add_socket(socket, ksess->consumer);
3346 rcu_read_unlock();
3347
3348 pthread_mutex_lock(&cdata->pid_mutex);
3349 cdata->pid = -1;
3350 pthread_mutex_unlock(&cdata->pid_mutex);
3351
3352 break;
3353 }
3354 default:
3355 /* TODO: Userspace tracing */
3356 ret = LTTNG_ERR_UND;
3357 goto error;
3358 }
3359
3360 return LTTNG_OK;
3361
3362 error:
3363 if (socket) {
3364 consumer_destroy_socket(socket);
3365 }
3366 return ret;
3367 }
3368
3369 /*
3370 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3371 */
3372 ssize_t cmd_list_domains(struct ltt_session *session,
3373 struct lttng_domain **domains)
3374 {
3375 int ret, index = 0;
3376 ssize_t nb_dom = 0;
3377 struct agent *agt;
3378 struct lttng_ht_iter iter;
3379
3380 if (session->kernel_session != NULL) {
3381 DBG3("Listing domains found kernel domain");
3382 nb_dom++;
3383 }
3384
3385 if (session->ust_session != NULL) {
3386 DBG3("Listing domains found UST global domain");
3387 nb_dom++;
3388
3389 rcu_read_lock();
3390 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3391 agt, node.node) {
3392 if (agt->being_used) {
3393 nb_dom++;
3394 }
3395 }
3396 rcu_read_unlock();
3397 }
3398
3399 if (!nb_dom) {
3400 goto end;
3401 }
3402
3403 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3404 if (*domains == NULL) {
3405 ret = LTTNG_ERR_FATAL;
3406 goto error;
3407 }
3408
3409 if (session->kernel_session != NULL) {
3410 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3411
3412 /* Kernel session buffer type is always GLOBAL */
3413 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3414
3415 index++;
3416 }
3417
3418 if (session->ust_session != NULL) {
3419 (*domains)[index].type = LTTNG_DOMAIN_UST;
3420 (*domains)[index].buf_type = session->ust_session->buffer_type;
3421 index++;
3422
3423 rcu_read_lock();
3424 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3425 agt, node.node) {
3426 if (agt->being_used) {
3427 (*domains)[index].type = agt->domain;
3428 (*domains)[index].buf_type = session->ust_session->buffer_type;
3429 index++;
3430 }
3431 }
3432 rcu_read_unlock();
3433 }
3434 end:
3435 return nb_dom;
3436
3437 error:
3438 /* Return negative value to differentiate return code */
3439 return -ret;
3440 }
3441
3442
3443 /*
3444 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3445 */
3446 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3447 struct ltt_session *session, struct lttng_channel **channels)
3448 {
3449 ssize_t nb_chan = 0, payload_size = 0, ret;
3450
3451 switch (domain) {
3452 case LTTNG_DOMAIN_KERNEL:
3453 if (session->kernel_session != NULL) {
3454 nb_chan = session->kernel_session->channel_count;
3455 }
3456 DBG3("Number of kernel channels %zd", nb_chan);
3457 if (nb_chan <= 0) {
3458 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3459 goto end;
3460 }
3461 break;
3462 case LTTNG_DOMAIN_UST:
3463 if (session->ust_session != NULL) {
3464 rcu_read_lock();
3465 nb_chan = lttng_ht_get_count(
3466 session->ust_session->domain_global.channels);
3467 rcu_read_unlock();
3468 }
3469 DBG3("Number of UST global channels %zd", nb_chan);
3470 if (nb_chan < 0) {
3471 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3472 goto end;
3473 }
3474 break;
3475 default:
3476 ret = -LTTNG_ERR_UND;
3477 goto end;
3478 }
3479
3480 if (nb_chan > 0) {
3481 const size_t channel_size = sizeof(struct lttng_channel) +
3482 sizeof(struct lttng_channel_extended);
3483 struct lttng_channel_extended *channel_exts;
3484
3485 payload_size = nb_chan * channel_size;
3486 *channels = zmalloc(payload_size);
3487 if (*channels == NULL) {
3488 ret = -LTTNG_ERR_FATAL;
3489 goto end;
3490 }
3491
3492 channel_exts = ((void *) *channels) +
3493 (nb_chan * sizeof(struct lttng_channel));
3494 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3495 if (ret != LTTNG_OK) {
3496 free(*channels);
3497 *channels = NULL;
3498 goto end;
3499 }
3500 } else {
3501 *channels = NULL;
3502 }
3503
3504 ret = payload_size;
3505 end:
3506 return ret;
3507 }
3508
3509 /*
3510 * Command LTTNG_LIST_EVENTS processed by the client thread.
3511 */
3512 ssize_t cmd_list_events(enum lttng_domain_type domain,
3513 struct ltt_session *session, char *channel_name,
3514 struct lttng_event **events, size_t *total_size)
3515 {
3516 int ret = 0;
3517 ssize_t nb_event = 0;
3518
3519 switch (domain) {
3520 case LTTNG_DOMAIN_KERNEL:
3521 if (session->kernel_session != NULL) {
3522 nb_event = list_lttng_kernel_events(channel_name,
3523 session->kernel_session, events,
3524 total_size);
3525 }
3526 break;
3527 case LTTNG_DOMAIN_UST:
3528 {
3529 if (session->ust_session != NULL) {
3530 nb_event = list_lttng_ust_global_events(channel_name,
3531 &session->ust_session->domain_global, events,
3532 total_size);
3533 }
3534 break;
3535 }
3536 case LTTNG_DOMAIN_LOG4J:
3537 case LTTNG_DOMAIN_JUL:
3538 case LTTNG_DOMAIN_PYTHON:
3539 if (session->ust_session) {
3540 struct lttng_ht_iter iter;
3541 struct agent *agt;
3542
3543 rcu_read_lock();
3544 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3545 &iter.iter, agt, node.node) {
3546 if (agt->domain == domain) {
3547 nb_event = list_lttng_agent_events(
3548 agt, events,
3549 total_size);
3550 break;
3551 }
3552 }
3553 rcu_read_unlock();
3554 }
3555 break;
3556 default:
3557 ret = LTTNG_ERR_UND;
3558 goto error;
3559 }
3560
3561 return nb_event;
3562
3563 error:
3564 /* Return negative value to differentiate return code */
3565 return -ret;
3566 }
3567
3568 /*
3569 * Using the session list, filled a lttng_session array to send back to the
3570 * client for session listing.
3571 *
3572 * The session list lock MUST be acquired before calling this function. Use
3573 * session_lock_list() and session_unlock_list().
3574 */
3575 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3576 size_t session_count, uid_t uid, gid_t gid)
3577 {
3578 int ret;
3579 unsigned int i = 0;
3580 struct ltt_session *session;
3581 struct ltt_session_list *list = session_get_list();
3582 struct lttng_session_extended *extended =
3583 (typeof(extended)) (&sessions[session_count]);
3584
3585 DBG("Getting all available session for UID %d GID %d",
3586 uid, gid);
3587 /*
3588 * Iterate over session list and append data after the control struct in
3589 * the buffer.
3590 */
3591 cds_list_for_each_entry(session, &list->head, list) {
3592 if (!session_get(session)) {
3593 continue;
3594 }
3595 /*
3596 * Only list the sessions the user can control.
3597 */
3598 if (!session_access_ok(session, uid, gid) ||
3599 session->destroyed) {
3600 session_put(session);
3601 continue;
3602 }
3603
3604 struct ltt_kernel_session *ksess = session->kernel_session;
3605 struct ltt_ust_session *usess = session->ust_session;
3606
3607 if (session->consumer->type == CONSUMER_DST_NET ||
3608 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3609 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3610 ret = build_network_session_path(sessions[i].path,
3611 sizeof(sessions[i].path), session);
3612 } else {
3613 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3614 session->consumer->dst.session_root_path);
3615 }
3616 if (ret < 0) {
3617 PERROR("snprintf session path");
3618 session_put(session);
3619 continue;
3620 }
3621
3622 strncpy(sessions[i].name, session->name, NAME_MAX);
3623 sessions[i].name[NAME_MAX - 1] = '\0';
3624 sessions[i].enabled = session->active;
3625 sessions[i].snapshot_mode = session->snapshot_mode;
3626 sessions[i].live_timer_interval = session->live_timer;
3627 extended[i].creation_time.value = (uint64_t) session->creation_time;
3628 extended[i].creation_time.is_set = 1;
3629 i++;
3630 session_put(session);
3631 }
3632 }
3633
3634 /*
3635 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3636 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3637 */
3638 int cmd_data_pending(struct ltt_session *session)
3639 {
3640 int ret;
3641 struct ltt_kernel_session *ksess = session->kernel_session;
3642 struct ltt_ust_session *usess = session->ust_session;
3643
3644 assert(session);
3645
3646 DBG("Data pending for session %s", session->name);
3647
3648 /* Session MUST be stopped to ask for data availability. */
3649 if (session->active) {
3650 ret = LTTNG_ERR_SESSION_STARTED;
3651 goto error;
3652 } else {
3653 /*
3654 * If stopped, just make sure we've started before else the above call
3655 * will always send that there is data pending.
3656 *
3657 * The consumer assumes that when the data pending command is received,
3658 * the trace has been started before or else no output data is written
3659 * by the streams which is a condition for data pending. So, this is
3660 * *VERY* important that we don't ask the consumer before a start
3661 * trace.
3662 */
3663 if (!session->has_been_started) {
3664 ret = 0;
3665 goto error;
3666 }
3667 }
3668
3669 /* A rotation is still pending, we have to wait. */
3670 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3671 DBG("Rotate still pending for session %s", session->name);
3672 ret = 1;
3673 goto error;
3674 }
3675
3676 if (ksess && ksess->consumer) {
3677 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3678 if (ret == 1) {
3679 /* Data is still being extracted for the kernel. */
3680 goto error;
3681 }
3682 }
3683
3684 if (usess && usess->consumer) {
3685 ret = consumer_is_data_pending(usess->id, usess->consumer);
3686 if (ret == 1) {
3687 /* Data is still being extracted for the kernel. */
3688 goto error;
3689 }
3690 }
3691
3692 /* Data is ready to be read by a viewer */
3693 ret = 0;
3694
3695 error:
3696 return ret;
3697 }
3698
3699 /*
3700 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3701 *
3702 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3703 */
3704 int cmd_snapshot_add_output(struct ltt_session *session,
3705 struct lttng_snapshot_output *output, uint32_t *id)
3706 {
3707 int ret;
3708 struct snapshot_output *new_output;
3709
3710 assert(session);
3711 assert(output);
3712
3713 DBG("Cmd snapshot add output for session %s", session->name);
3714
3715 /*
3716 * Can't create an output if the session is not set in no-output mode.
3717 */
3718 if (session->output_traces) {
3719 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3720 goto error;
3721 }
3722
3723 if (session->has_non_mmap_channel) {
3724 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3725 goto error;
3726 }
3727
3728 /* Only one output is allowed until we have the "tee" feature. */
3729 if (session->snapshot.nb_output == 1) {
3730 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3731 goto error;
3732 }
3733
3734 new_output = snapshot_output_alloc();
3735 if (!new_output) {
3736 ret = LTTNG_ERR_NOMEM;
3737 goto error;
3738 }
3739
3740 ret = snapshot_output_init(session, output->max_size, output->name,
3741 output->ctrl_url, output->data_url, session->consumer, new_output,
3742 &session->snapshot);
3743 if (ret < 0) {
3744 if (ret == -ENOMEM) {
3745 ret = LTTNG_ERR_NOMEM;
3746 } else {
3747 ret = LTTNG_ERR_INVALID;
3748 }
3749 goto free_error;
3750 }
3751
3752 rcu_read_lock();
3753 snapshot_add_output(&session->snapshot, new_output);
3754 if (id) {
3755 *id = new_output->id;
3756 }
3757 rcu_read_unlock();
3758
3759 return LTTNG_OK;
3760
3761 free_error:
3762 snapshot_output_destroy(new_output);
3763 error:
3764 return ret;
3765 }
3766
3767 /*
3768 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3769 *
3770 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3771 */
3772 int cmd_snapshot_del_output(struct ltt_session *session,
3773 struct lttng_snapshot_output *output)
3774 {
3775 int ret;
3776 struct snapshot_output *sout = NULL;
3777
3778 assert(session);
3779 assert(output);
3780
3781 rcu_read_lock();
3782
3783 /*
3784 * Permission denied to create an output if the session is not
3785 * set in no output mode.
3786 */
3787 if (session->output_traces) {
3788 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3789 goto error;
3790 }
3791
3792 if (output->id) {
3793 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3794 session->name);
3795 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3796 } else if (*output->name != '\0') {
3797 DBG("Cmd snapshot del output name %s for session %s", output->name,
3798 session->name);
3799 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3800 }
3801 if (!sout) {
3802 ret = LTTNG_ERR_INVALID;
3803 goto error;
3804 }
3805
3806 snapshot_delete_output(&session->snapshot, sout);
3807 snapshot_output_destroy(sout);
3808 ret = LTTNG_OK;
3809
3810 error:
3811 rcu_read_unlock();
3812 return ret;
3813 }
3814
3815 /*
3816 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3817 *
3818 * If no output is available, outputs is untouched and 0 is returned.
3819 *
3820 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3821 */
3822 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3823 struct lttng_snapshot_output **outputs)
3824 {
3825 int ret, idx = 0;
3826 struct lttng_snapshot_output *list = NULL;
3827 struct lttng_ht_iter iter;
3828 struct snapshot_output *output;
3829
3830 assert(session);
3831 assert(outputs);
3832
3833 DBG("Cmd snapshot list outputs for session %s", session->name);
3834
3835 /*
3836 * Permission denied to create an output if the session is not
3837 * set in no output mode.
3838 */
3839 if (session->output_traces) {
3840 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3841 goto end;
3842 }
3843
3844 if (session->snapshot.nb_output == 0) {
3845 ret = 0;
3846 goto end;
3847 }
3848
3849 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3850 if (!list) {
3851 ret = -LTTNG_ERR_NOMEM;
3852 goto end;
3853 }
3854
3855 /* Copy list from session to the new list object. */
3856 rcu_read_lock();
3857 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
3858 output, node.node) {
3859 assert(output->consumer);
3860 list[idx].id = output->id;
3861 list[idx].max_size = output->max_size;
3862 if (lttng_strncpy(list[idx].name, output->name,
3863 sizeof(list[idx].name))) {
3864 ret = -LTTNG_ERR_INVALID;
3865 goto error;
3866 }
3867 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3868 if (lttng_strncpy(list[idx].ctrl_url,
3869 output->consumer->dst.session_root_path,
3870 sizeof(list[idx].ctrl_url))) {
3871 ret = -LTTNG_ERR_INVALID;
3872 goto error;
3873 }
3874 } else {
3875 /* Control URI. */
3876 ret = uri_to_str_url(&output->consumer->dst.net.control,
3877 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3878 if (ret < 0) {
3879 ret = -LTTNG_ERR_NOMEM;
3880 goto error;
3881 }
3882
3883 /* Data URI. */
3884 ret = uri_to_str_url(&output->consumer->dst.net.data,
3885 list[idx].data_url, sizeof(list[idx].data_url));
3886 if (ret < 0) {
3887 ret = -LTTNG_ERR_NOMEM;
3888 goto error;
3889 }
3890 }
3891 idx++;
3892 }
3893
3894 *outputs = list;
3895 list = NULL;
3896 ret = session->snapshot.nb_output;
3897 error:
3898 rcu_read_unlock();
3899 free(list);
3900 end:
3901 return ret;
3902 }
3903
3904 /*
3905 * Check if we can regenerate the metadata for this session.
3906 * Only kernel, UST per-uid and non-live sessions are supported.
3907 *
3908 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
3909 */
3910 static
3911 int check_regenerate_metadata_support(struct ltt_session *session)
3912 {
3913 int ret;
3914
3915 assert(session);
3916
3917 if (session->live_timer != 0) {
3918 ret = LTTNG_ERR_LIVE_SESSION;
3919 goto end;
3920 }
3921 if (!session->active) {
3922 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3923 goto end;
3924 }
3925 if (session->ust_session) {
3926 switch (session->ust_session->buffer_type) {
3927 case LTTNG_BUFFER_PER_UID:
3928 break;
3929 case LTTNG_BUFFER_PER_PID:
3930 ret = LTTNG_ERR_PER_PID_SESSION;
3931 goto end;
3932 default:
3933 assert(0);
3934 ret = LTTNG_ERR_UNK;
3935 goto end;
3936 }
3937 }
3938 if (session->consumer->type == CONSUMER_DST_NET &&
3939 session->consumer->relay_minor_version < 8) {
3940 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
3941 goto end;
3942 }
3943 ret = 0;
3944
3945 end:
3946 return ret;
3947 }
3948
3949 static
3950 int clear_metadata_file(int fd)
3951 {
3952 int ret;
3953 off_t lseek_ret;
3954
3955 lseek_ret = lseek(fd, 0, SEEK_SET);
3956 if (lseek_ret < 0) {
3957 PERROR("lseek");
3958 ret = -1;
3959 goto end;
3960 }
3961
3962 ret = ftruncate(fd, 0);
3963 if (ret < 0) {
3964 PERROR("ftruncate");
3965 goto end;
3966 }
3967
3968 end:
3969 return ret;
3970 }
3971
3972 static
3973 int ust_regenerate_metadata(struct ltt_ust_session *usess)
3974 {
3975 int ret = 0;
3976 struct buffer_reg_uid *uid_reg = NULL;
3977 struct buffer_reg_session *session_reg = NULL;
3978
3979 rcu_read_lock();
3980 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
3981 struct ust_registry_session *registry;
3982 struct ust_registry_channel *chan;
3983 struct lttng_ht_iter iter_chan;
3984
3985 session_reg = uid_reg->registry;
3986 registry = session_reg->reg.ust;
3987
3988 pthread_mutex_lock(&registry->lock);
3989 registry->metadata_len_sent = 0;
3990 memset(registry->metadata, 0, registry->metadata_alloc_len);
3991 registry->metadata_len = 0;
3992 registry->metadata_version++;
3993 if (registry->metadata_fd > 0) {
3994 /* Clear the metadata file's content. */
3995 ret = clear_metadata_file(registry->metadata_fd);
3996 if (ret) {
3997 pthread_mutex_unlock(&registry->lock);
3998 goto end;
3999 }
4000 }
4001
4002 ret = ust_metadata_session_statedump(registry, NULL,
4003 registry->major, registry->minor);
4004 if (ret) {
4005 pthread_mutex_unlock(&registry->lock);
4006 ERR("Failed to generate session metadata (err = %d)",
4007 ret);
4008 goto end;
4009 }
4010 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4011 chan, node.node) {
4012 struct ust_registry_event *event;
4013 struct lttng_ht_iter iter_event;
4014
4015 ret = ust_metadata_channel_statedump(registry, chan);
4016 if (ret) {
4017 pthread_mutex_unlock(&registry->lock);
4018 ERR("Failed to generate channel metadata "
4019 "(err = %d)", ret);
4020 goto end;
4021 }
4022 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4023 event, node.node) {
4024 ret = ust_metadata_event_statedump(registry,
4025 chan, event);
4026 if (ret) {
4027 pthread_mutex_unlock(&registry->lock);
4028 ERR("Failed to generate event metadata "
4029 "(err = %d)", ret);
4030 goto end;
4031 }
4032 }
4033 }
4034 pthread_mutex_unlock(&registry->lock);
4035 }
4036
4037 end:
4038 rcu_read_unlock();
4039 return ret;
4040 }
4041
4042 /*
4043 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4044 *
4045 * Ask the consumer to truncate the existing metadata file(s) and
4046 * then regenerate the metadata. Live and per-pid sessions are not
4047 * supported and return an error.
4048 *
4049 * Return 0 on success or else a LTTNG_ERR code.
4050 */
4051 int cmd_regenerate_metadata(struct ltt_session *session)
4052 {
4053 int ret;
4054
4055 assert(session);
4056
4057 ret = check_regenerate_metadata_support(session);
4058 if (ret) {
4059 goto end;
4060 }
4061
4062 if (session->kernel_session) {
4063 ret = kernctl_session_regenerate_metadata(
4064 session->kernel_session->fd);
4065 if (ret < 0) {
4066 ERR("Failed to regenerate the kernel metadata");
4067 goto end;
4068 }
4069 }
4070
4071 if (session->ust_session) {
4072 ret = ust_regenerate_metadata(session->ust_session);
4073 if (ret < 0) {
4074 ERR("Failed to regenerate the UST metadata");
4075 goto end;
4076 }
4077 }
4078 DBG("Cmd metadata regenerate for session %s", session->name);
4079 ret = LTTNG_OK;
4080
4081 end:
4082 return ret;
4083 }
4084
4085 /*
4086 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4087 *
4088 * Ask the tracer to regenerate a new statedump.
4089 *
4090 * Return 0 on success or else a LTTNG_ERR code.
4091 */
4092 int cmd_regenerate_statedump(struct ltt_session *session)
4093 {
4094 int ret;
4095
4096 assert(session);
4097
4098 if (!session->active) {
4099 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4100 goto end;
4101 }
4102
4103 if (session->kernel_session) {
4104 ret = kernctl_session_regenerate_statedump(
4105 session->kernel_session->fd);
4106 /*
4107 * Currently, the statedump in kernel can only fail if out
4108 * of memory.
4109 */
4110 if (ret < 0) {
4111 if (ret == -ENOMEM) {
4112 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4113 } else {
4114 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4115 }
4116 ERR("Failed to regenerate the kernel statedump");
4117 goto end;
4118 }
4119 }
4120
4121 if (session->ust_session) {
4122 ret = ust_app_regenerate_statedump_all(session->ust_session);
4123 /*
4124 * Currently, the statedump in UST always returns 0.
4125 */
4126 if (ret < 0) {
4127 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4128 ERR("Failed to regenerate the UST statedump");
4129 goto end;
4130 }
4131 }
4132 DBG("Cmd regenerate statedump for session %s", session->name);
4133 ret = LTTNG_OK;
4134
4135 end:
4136 return ret;
4137 }
4138
4139 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4140 struct notification_thread_handle *notification_thread)
4141 {
4142 int ret;
4143 size_t trigger_len;
4144 ssize_t sock_recv_len;
4145 struct lttng_trigger *trigger = NULL;
4146 struct lttng_buffer_view view;
4147 struct lttng_dynamic_buffer trigger_buffer;
4148
4149 lttng_dynamic_buffer_init(&trigger_buffer);
4150 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4151 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4152 if (ret) {
4153 ret = LTTNG_ERR_NOMEM;
4154 goto end;
4155 }
4156
4157 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4158 trigger_len);
4159 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4160 ERR("Failed to receive \"register trigger\" command payload");
4161 /* TODO: should this be a new error enum ? */
4162 ret = LTTNG_ERR_INVALID_TRIGGER;
4163 goto end;
4164 }
4165
4166 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4167 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4168 trigger_len) {
4169 ERR("Invalid trigger payload received in \"register trigger\" command");
4170 ret = LTTNG_ERR_INVALID_TRIGGER;
4171 goto end;
4172 }
4173
4174 ret = notification_thread_command_register_trigger(notification_thread,
4175 trigger);
4176 /* Ownership of trigger was transferred. */
4177 trigger = NULL;
4178 end:
4179 lttng_trigger_destroy(trigger);
4180 lttng_dynamic_buffer_reset(&trigger_buffer);
4181 return ret;
4182 }
4183
4184 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4185 struct notification_thread_handle *notification_thread)
4186 {
4187 int ret;
4188 size_t trigger_len;
4189 ssize_t sock_recv_len;
4190 struct lttng_trigger *trigger = NULL;
4191 struct lttng_buffer_view view;
4192 struct lttng_dynamic_buffer trigger_buffer;
4193
4194 lttng_dynamic_buffer_init(&trigger_buffer);
4195 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4196 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4197 if (ret) {
4198 ret = LTTNG_ERR_NOMEM;
4199 goto end;
4200 }
4201
4202 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4203 trigger_len);
4204 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4205 ERR("Failed to receive \"unregister trigger\" command payload");
4206 /* TODO: should this be a new error enum ? */
4207 ret = LTTNG_ERR_INVALID_TRIGGER;
4208 goto end;
4209 }
4210
4211 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4212 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4213 trigger_len) {
4214 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4215 ret = LTTNG_ERR_INVALID_TRIGGER;
4216 goto end;
4217 }
4218
4219 ret = notification_thread_command_unregister_trigger(notification_thread,
4220 trigger);
4221 end:
4222 lttng_trigger_destroy(trigger);
4223 lttng_dynamic_buffer_reset(&trigger_buffer);
4224 return ret;
4225 }
4226
4227 /*
4228 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4229 * snapshot output is *not* set with a remote destination.
4230 *
4231 * Return LTTNG_OK on success or a LTTNG_ERR code.
4232 */
4233 static enum lttng_error_code set_relayd_for_snapshot(
4234 struct consumer_output *output,
4235 const struct ltt_session *session)
4236 {
4237 enum lttng_error_code status = LTTNG_OK;
4238 struct lttng_ht_iter iter;
4239 struct consumer_socket *socket;
4240 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4241 const char *base_path;
4242
4243 assert(output);
4244 assert(session);
4245
4246 DBG2("Set relayd object from snapshot output");
4247
4248 if (session->current_trace_chunk) {
4249 enum lttng_trace_chunk_status chunk_status =
4250 lttng_trace_chunk_get_id(
4251 session->current_trace_chunk,
4252 &current_chunk_id.value);
4253
4254 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4255 current_chunk_id.is_set = true;
4256 } else {
4257 ERR("Failed to get current trace chunk id");
4258 status = LTTNG_ERR_UNK;
4259 goto error;
4260 }
4261 }
4262
4263 /* Ignore if snapshot consumer output is not network. */
4264 if (output->type != CONSUMER_DST_NET) {
4265 goto error;
4266 }
4267
4268 /*
4269 * The snapshot record URI base path overrides the session
4270 * base path.
4271 */
4272 if (output->dst.net.control.subdir[0] != '\0') {
4273 base_path = output->dst.net.control.subdir;
4274 } else {
4275 base_path = session->base_path;
4276 }
4277
4278 /*
4279 * For each consumer socket, create and send the relayd object of the
4280 * snapshot output.
4281 */
4282 rcu_read_lock();
4283 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4284 socket, node.node) {
4285 pthread_mutex_lock(socket->lock);
4286 status = send_consumer_relayd_sockets(0, session->id,
4287 output, socket,
4288 session->name, session->hostname,
4289 base_path,
4290 session->live_timer,
4291 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4292 session->creation_time);
4293 pthread_mutex_unlock(socket->lock);
4294 if (status != LTTNG_OK) {
4295 rcu_read_unlock();
4296 goto error;
4297 }
4298 }
4299 rcu_read_unlock();
4300
4301 error:
4302 return status;
4303 }
4304
4305 /*
4306 * Record a kernel snapshot.
4307 *
4308 * Return LTTNG_OK on success or a LTTNG_ERR code.
4309 */
4310 static enum lttng_error_code record_kernel_snapshot(
4311 struct ltt_kernel_session *ksess,
4312 const struct consumer_output *output,
4313 const struct ltt_session *session,
4314 int wait, uint64_t nb_packets_per_stream)
4315 {
4316 enum lttng_error_code status;
4317
4318 assert(ksess);
4319 assert(output);
4320 assert(session);
4321
4322 status = kernel_snapshot_record(
4323 ksess, output, wait, nb_packets_per_stream);
4324 return status;
4325 }
4326
4327 /*
4328 * Record a UST snapshot.
4329 *
4330 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4331 */
4332 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4333 const struct consumer_output *output,
4334 const struct ltt_session *session,
4335 int wait, uint64_t nb_packets_per_stream)
4336 {
4337 enum lttng_error_code status;
4338
4339 assert(usess);
4340 assert(output);
4341 assert(session);
4342
4343 status = ust_app_snapshot_record(
4344 usess, output, wait, nb_packets_per_stream);
4345 return status;
4346 }
4347
4348 static
4349 uint64_t get_session_size_one_more_packet_per_stream(
4350 const struct ltt_session *session, uint64_t cur_nr_packets)
4351 {
4352 uint64_t tot_size = 0;
4353
4354 if (session->kernel_session) {
4355 struct ltt_kernel_channel *chan;
4356 const struct ltt_kernel_session *ksess =
4357 session->kernel_session;
4358
4359 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4360 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4361 /*
4362 * Don't take channel into account if we
4363 * already grab all its packets.
4364 */
4365 continue;
4366 }
4367 tot_size += chan->channel->attr.subbuf_size
4368 * chan->stream_count;
4369 }
4370 }
4371
4372 if (session->ust_session) {
4373 const struct ltt_ust_session *usess = session->ust_session;
4374
4375 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4376 cur_nr_packets);
4377 }
4378
4379 return tot_size;
4380 }
4381
4382 /*
4383 * Calculate the number of packets we can grab from each stream that
4384 * fits within the overall snapshot max size.
4385 *
4386 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4387 * the number of packets per stream.
4388 *
4389 * TODO: this approach is not perfect: we consider the worse case
4390 * (packet filling the sub-buffers) as an upper bound, but we could do
4391 * better if we do this calculation while we actually grab the packet
4392 * content: we would know how much padding we don't actually store into
4393 * the file.
4394 *
4395 * This algorithm is currently bounded by the number of packets per
4396 * stream.
4397 *
4398 * Since we call this algorithm before actually grabbing the data, it's
4399 * an approximation: for instance, applications could appear/disappear
4400 * in between this call and actually grabbing data.
4401 */
4402 static
4403 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4404 uint64_t max_size)
4405 {
4406 int64_t size_left;
4407 uint64_t cur_nb_packets = 0;
4408
4409 if (!max_size) {
4410 return 0; /* Infinite */
4411 }
4412
4413 size_left = max_size;
4414 for (;;) {
4415 uint64_t one_more_packet_tot_size;
4416
4417 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4418 session, cur_nb_packets);
4419 if (!one_more_packet_tot_size) {
4420 /* We are already grabbing all packets. */
4421 break;
4422 }
4423 size_left -= one_more_packet_tot_size;
4424 if (size_left < 0) {
4425 break;
4426 }
4427 cur_nb_packets++;
4428 }
4429 if (!cur_nb_packets) {
4430 /* Not enough room to grab one packet of each stream, error. */
4431 return -1;
4432 }
4433 return cur_nb_packets;
4434 }
4435
4436 static
4437 enum lttng_error_code snapshot_record(struct ltt_session *session,
4438 const struct snapshot_output *snapshot_output, int wait)
4439 {
4440 int64_t nb_packets_per_stream;
4441 char snapshot_chunk_name[LTTNG_NAME_MAX];
4442 int ret;
4443 enum lttng_error_code ret_code = LTTNG_OK;
4444 struct lttng_trace_chunk *snapshot_trace_chunk;
4445 struct consumer_output *original_ust_consumer_output = NULL;
4446 struct consumer_output *original_kernel_consumer_output = NULL;
4447 struct consumer_output *snapshot_ust_consumer_output = NULL;
4448 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4449
4450 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4451 "%s-%s-%" PRIu64,
4452 snapshot_output->name,
4453 snapshot_output->datetime,
4454 snapshot_output->nb_snapshot);
4455 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4456 ERR("Failed to format snapshot name");
4457 ret_code = LTTNG_ERR_INVALID;
4458 goto error;
4459 }
4460 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4461 snapshot_output->name, session->name,
4462 snapshot_chunk_name);
4463 if (!session->kernel_session && !session->ust_session) {
4464 ERR("Failed to record snapshot as no channels exist");
4465 ret_code = LTTNG_ERR_NO_CHANNEL;
4466 goto error;
4467 }
4468
4469 if (session->kernel_session) {
4470 original_kernel_consumer_output =
4471 session->kernel_session->consumer;
4472 snapshot_kernel_consumer_output =
4473 consumer_copy_output(snapshot_output->consumer);
4474 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4475 original_kernel_consumer_output);
4476 if (ret < 0) {
4477 ERR("Failed to copy consumer sockets from snapshot output configuration");
4478 ret_code = LTTNG_ERR_NOMEM;
4479 goto error;
4480 }
4481 ret_code = set_relayd_for_snapshot(
4482 snapshot_kernel_consumer_output, session);
4483 if (ret_code != LTTNG_OK) {
4484 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4485 goto error;
4486 }
4487 session->kernel_session->consumer =
4488 snapshot_kernel_consumer_output;
4489 }
4490 if (session->ust_session) {
4491 original_ust_consumer_output = session->ust_session->consumer;
4492 snapshot_ust_consumer_output =
4493 consumer_copy_output(snapshot_output->consumer);
4494 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4495 original_ust_consumer_output);
4496 if (ret < 0) {
4497 ERR("Failed to copy consumer sockets from snapshot output configuration");
4498 ret_code = LTTNG_ERR_NOMEM;
4499 goto error;
4500 }
4501 ret_code = set_relayd_for_snapshot(
4502 snapshot_ust_consumer_output, session);
4503 if (ret_code != LTTNG_OK) {
4504 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4505 goto error;
4506 }
4507 session->ust_session->consumer =
4508 snapshot_ust_consumer_output;
4509 }
4510
4511 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4512 snapshot_kernel_consumer_output ?:
4513 snapshot_ust_consumer_output,
4514 consumer_output_get_base_path(
4515 snapshot_output->consumer),
4516 snapshot_chunk_name);
4517 if (!snapshot_trace_chunk) {
4518 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
4519 session->name);
4520 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
4521 goto error;
4522 }
4523 assert(!session->current_trace_chunk);
4524 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4525 lttng_trace_chunk_put(snapshot_trace_chunk);
4526 snapshot_trace_chunk = NULL;
4527 if (ret) {
4528 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
4529 session->name);
4530 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4531 goto error;
4532 }
4533
4534 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4535 snapshot_output->max_size);
4536 if (nb_packets_per_stream < 0) {
4537 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
4538 goto error;
4539 }
4540
4541 if (session->kernel_session) {
4542 ret_code = record_kernel_snapshot(session->kernel_session,
4543 snapshot_kernel_consumer_output, session,
4544 wait, nb_packets_per_stream);
4545 if (ret_code != LTTNG_OK) {
4546 goto error;
4547 }
4548 }
4549
4550 if (session->ust_session) {
4551 ret_code = record_ust_snapshot(session->ust_session,
4552 snapshot_ust_consumer_output, session,
4553 wait, nb_packets_per_stream);
4554 if (ret_code != LTTNG_OK) {
4555 goto error;
4556 }
4557 }
4558
4559 if (session_close_trace_chunk(
4560 session, session->current_trace_chunk, NULL)) {
4561 /*
4562 * Don't goto end; make sure the chunk is closed for the session
4563 * to allow future snapshots.
4564 */
4565 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4566 session->name);
4567 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4568 }
4569 if (session_set_trace_chunk(session, NULL, NULL)) {
4570 ERR("Failed to release the current trace chunk of session \"%s\"",
4571 session->name);
4572 ret_code = LTTNG_ERR_UNK;
4573 }
4574 error:
4575 if (original_ust_consumer_output) {
4576 session->ust_session->consumer = original_ust_consumer_output;
4577 }
4578 if (original_kernel_consumer_output) {
4579 session->kernel_session->consumer =
4580 original_kernel_consumer_output;
4581 }
4582 consumer_output_put(snapshot_ust_consumer_output);
4583 consumer_output_put(snapshot_kernel_consumer_output);
4584 return ret_code;
4585 }
4586
4587 /*
4588 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4589 *
4590 * The wait parameter is ignored so this call always wait for the snapshot to
4591 * complete before returning.
4592 *
4593 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4594 */
4595 int cmd_snapshot_record(struct ltt_session *session,
4596 struct lttng_snapshot_output *output, int wait)
4597 {
4598 enum lttng_error_code cmd_ret = LTTNG_OK;
4599 int ret;
4600 unsigned int snapshot_success = 0;
4601 char datetime[16];
4602 struct snapshot_output *tmp_output = NULL;
4603
4604 assert(session);
4605 assert(output);
4606
4607 DBG("Cmd snapshot record for session %s", session->name);
4608
4609 /* Get the datetime for the snapshot output directory. */
4610 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4611 sizeof(datetime));
4612 if (!ret) {
4613 cmd_ret = LTTNG_ERR_INVALID;
4614 goto error;
4615 }
4616
4617 /*
4618 * Permission denied to create an output if the session is not
4619 * set in no output mode.
4620 */
4621 if (session->output_traces) {
4622 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4623 goto error;
4624 }
4625
4626 /* The session needs to be started at least once. */
4627 if (!session->has_been_started) {
4628 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4629 goto error;
4630 }
4631
4632 /* Use temporary output for the session. */
4633 if (*output->ctrl_url != '\0') {
4634 tmp_output = snapshot_output_alloc();
4635 if (!tmp_output) {
4636 cmd_ret = LTTNG_ERR_NOMEM;
4637 goto error;
4638 }
4639
4640 ret = snapshot_output_init(session, output->max_size,
4641 output->name,
4642 output->ctrl_url, output->data_url,
4643 session->consumer,
4644 tmp_output, NULL);
4645 if (ret < 0) {
4646 if (ret == -ENOMEM) {
4647 cmd_ret = LTTNG_ERR_NOMEM;
4648 } else {
4649 cmd_ret = LTTNG_ERR_INVALID;
4650 }
4651 goto error;
4652 }
4653 /* Use the global session count for the temporary snapshot. */
4654 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
4655
4656 /* Use the global datetime */
4657 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
4658 cmd_ret = snapshot_record(session, tmp_output, wait);
4659 if (cmd_ret != LTTNG_OK) {
4660 goto error;
4661 }
4662 snapshot_success = 1;
4663 } else {
4664 struct snapshot_output *sout;
4665 struct lttng_ht_iter iter;
4666
4667 rcu_read_lock();
4668 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4669 &iter.iter, sout, node.node) {
4670 struct snapshot_output output_copy;
4671
4672 /*
4673 * Make a local copy of the output and override output
4674 * parameters with those provided as part of the
4675 * command.
4676 */
4677 memcpy(&output_copy, sout, sizeof(output_copy));
4678
4679 if (output->max_size != (uint64_t) -1ULL) {
4680 output_copy.max_size = output->max_size;
4681 }
4682
4683 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
4684 memcpy(output_copy.datetime, datetime,
4685 sizeof(datetime));
4686
4687 /* Use temporary name. */
4688 if (*output->name != '\0') {
4689 if (lttng_strncpy(output_copy.name,
4690 output->name,
4691 sizeof(output_copy.name))) {
4692 cmd_ret = LTTNG_ERR_INVALID;
4693 rcu_read_unlock();
4694 goto error;
4695 }
4696 }
4697
4698 cmd_ret = snapshot_record(session, &output_copy, wait);
4699 if (cmd_ret != LTTNG_OK) {
4700 rcu_read_unlock();
4701 goto error;
4702 }
4703 snapshot_success = 1;
4704 }
4705 rcu_read_unlock();
4706 }
4707
4708 if (snapshot_success) {
4709 session->snapshot.nb_snapshot++;
4710 } else {
4711 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4712 }
4713
4714 error:
4715 if (tmp_output) {
4716 snapshot_output_destroy(tmp_output);
4717 }
4718 return cmd_ret;
4719 }
4720
4721 /*
4722 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4723 */
4724 int cmd_set_session_shm_path(struct ltt_session *session,
4725 const char *shm_path)
4726 {
4727 /* Safety net */
4728 assert(session);
4729
4730 /*
4731 * Can only set shm path before session is started.
4732 */
4733 if (session->has_been_started) {
4734 return LTTNG_ERR_SESSION_STARTED;
4735 }
4736
4737 strncpy(session->shm_path, shm_path,
4738 sizeof(session->shm_path));
4739 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4740
4741 return 0;
4742 }
4743
4744 /*
4745 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4746 *
4747 * Ask the consumer to rotate the session output directory.
4748 * The session lock must be held.
4749 *
4750 * Returns LTTNG_OK on success or else a negative LTTng error code.
4751 */
4752 int cmd_rotate_session(struct ltt_session *session,
4753 struct lttng_rotate_session_return *rotate_return,
4754 bool quiet_rotation)
4755 {
4756 int ret;
4757 uint64_t ongoing_rotation_chunk_id;
4758 enum lttng_error_code cmd_ret = LTTNG_OK;
4759 struct lttng_trace_chunk *chunk_being_archived = NULL;
4760 struct lttng_trace_chunk *new_trace_chunk = NULL;
4761 enum lttng_trace_chunk_status chunk_status;
4762
4763 assert(session);
4764
4765 if (!session->has_been_started) {
4766 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4767 goto end;
4768 }
4769
4770 /*
4771 * Explicit rotation is not supported for live sessions.
4772 * However, live sessions can perform a quiet rotation on
4773 * destroy.
4774 * Rotation is not supported for snapshot traces (no output).
4775 */
4776 if ((!quiet_rotation && session->live_timer) ||
4777 !session->output_traces) {
4778 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4779 goto end;
4780 }
4781
4782 /* Unsupported feature in lttng-relayd before 2.11. */
4783 if (session->consumer->type == CONSUMER_DST_NET &&
4784 (session->consumer->relay_major_version == 2 &&
4785 session->consumer->relay_minor_version < 11)) {
4786 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4787 goto end;
4788 }
4789
4790 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4791 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
4792 session->name);
4793 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
4794 goto end;
4795 }
4796
4797 /*
4798 * After a stop, we only allow one rotation to occur, the other ones are
4799 * useless until a new start.
4800 */
4801 if (session->rotated_after_last_stop) {
4802 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4803 session->name);
4804 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4805 goto end;
4806 }
4807
4808 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
4809
4810 if (session->active) {
4811 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
4812 NULL, NULL);
4813 if (!new_trace_chunk) {
4814 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
4815 goto error;
4816 }
4817 }
4818
4819 /* The current trace chunk becomes the chunk being archived. */
4820 ret = session_set_trace_chunk(session, new_trace_chunk,
4821 &chunk_being_archived);
4822 if (ret) {
4823 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4824 goto error;
4825 }
4826
4827 assert(chunk_being_archived);
4828 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
4829 &ongoing_rotation_chunk_id);
4830 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
4831
4832 if (session->kernel_session) {
4833 cmd_ret = kernel_rotate_session(session);
4834 if (cmd_ret != LTTNG_OK) {
4835 goto error;
4836 }
4837 }
4838 if (session->ust_session) {
4839 cmd_ret = ust_app_rotate_session(session);
4840 if (cmd_ret != LTTNG_OK) {
4841 goto error;
4842 }
4843 }
4844
4845 ret = session_close_trace_chunk(session, chunk_being_archived,
4846 quiet_rotation ?
4847 NULL :
4848 &((enum lttng_trace_chunk_command_type){
4849 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED}));
4850 if (ret) {
4851 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4852 goto error;
4853 }
4854
4855 session->quiet_rotation = quiet_rotation;
4856 ret = timer_session_rotation_pending_check_start(session,
4857 DEFAULT_ROTATE_PENDING_TIMER);
4858 if (ret) {
4859 cmd_ret = LTTNG_ERR_UNK;
4860 goto error;
4861 }
4862
4863 if (!session->active) {
4864 session->rotated_after_last_stop = true;
4865 }
4866
4867 if (rotate_return) {
4868 rotate_return->rotation_id = ongoing_rotation_chunk_id;
4869 }
4870
4871 session->chunk_being_archived = chunk_being_archived;
4872 chunk_being_archived = NULL;
4873 if (!quiet_rotation) {
4874 ret = notification_thread_command_session_rotation_ongoing(
4875 notification_thread_handle,
4876 session->name, session->uid, session->gid,
4877 ongoing_rotation_chunk_id);
4878 if (ret != LTTNG_OK) {
4879 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
4880 session->name);
4881 cmd_ret = ret;
4882 }
4883 }
4884
4885 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
4886 session->name, ongoing_rotation_chunk_id);
4887 end:
4888 lttng_trace_chunk_put(new_trace_chunk);
4889 lttng_trace_chunk_put(chunk_being_archived);
4890 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
4891 return ret;
4892 error:
4893 if (session_reset_rotation_state(session,
4894 LTTNG_ROTATION_STATE_ERROR)) {
4895 ERR("Failed to reset rotation state of session \"%s\"",
4896 session->name);
4897 }
4898 goto end;
4899 }
4900
4901 /*
4902 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
4903 *
4904 * Check if the session has finished its rotation.
4905 *
4906 * Return LTTNG_OK on success or else an LTTNG_ERR code.
4907 */
4908 int cmd_rotate_get_info(struct ltt_session *session,
4909 struct lttng_rotation_get_info_return *info_return,
4910 uint64_t rotation_id)
4911 {
4912 enum lttng_error_code cmd_ret = LTTNG_OK;
4913 enum lttng_rotation_state rotation_state;
4914
4915 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
4916 session->most_recent_chunk_id.value);
4917
4918 if (session->chunk_being_archived) {
4919 enum lttng_trace_chunk_status chunk_status;
4920 uint64_t chunk_id;
4921
4922 chunk_status = lttng_trace_chunk_get_id(
4923 session->chunk_being_archived,
4924 &chunk_id);
4925 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
4926
4927 rotation_state = rotation_id == chunk_id ?
4928 LTTNG_ROTATION_STATE_ONGOING :
4929 LTTNG_ROTATION_STATE_EXPIRED;
4930 } else {
4931 if (session->last_archived_chunk_id.is_set &&
4932 rotation_id != session->last_archived_chunk_id.value) {
4933 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
4934 } else {
4935 rotation_state = session->rotation_state;
4936 }
4937 }
4938
4939 switch (rotation_state) {
4940 case LTTNG_ROTATION_STATE_NO_ROTATION:
4941 DBG("Reporting that no rotation has occured within the lifetime of session \"%s\"",
4942 session->name);
4943 goto end;
4944 case LTTNG_ROTATION_STATE_EXPIRED:
4945 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
4946 rotation_id, session->name);
4947 break;
4948 case LTTNG_ROTATION_STATE_ONGOING:
4949 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
4950 rotation_id, session->name);
4951 break;
4952 case LTTNG_ROTATION_STATE_COMPLETED:
4953 {
4954 int fmt_ret;
4955 char *chunk_path;
4956 char *current_tracing_path_reply;
4957 size_t current_tracing_path_reply_len;
4958
4959 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
4960 rotation_id, session->name);
4961
4962 switch (session_get_consumer_destination_type(session)) {
4963 case CONSUMER_DST_LOCAL:
4964 current_tracing_path_reply =
4965 info_return->location.local.absolute_path;
4966 current_tracing_path_reply_len =
4967 sizeof(info_return->location.local.absolute_path);
4968 info_return->location_type =
4969 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
4970 break;
4971 case CONSUMER_DST_NET:
4972 current_tracing_path_reply =
4973 info_return->location.relay.relative_path;
4974 current_tracing_path_reply_len =
4975 sizeof(info_return->location.relay.relative_path);
4976 /* Currently the only supported relay protocol. */
4977 info_return->location.relay.protocol =
4978 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
4979
4980 fmt_ret = lttng_strncpy(info_return->location.relay.host,
4981 session_get_net_consumer_hostname(session),
4982 sizeof(info_return->location.relay.host));
4983 if (fmt_ret) {
4984 ERR("Failed to copy host name to rotate_get_info reply");
4985 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
4986 cmd_ret = LTTNG_ERR_SET_URL;
4987 goto end;
4988 }
4989
4990 session_get_net_consumer_ports(session,
4991 &info_return->location.relay.ports.control,
4992 &info_return->location.relay.ports.data);
4993 info_return->location_type =
4994 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
4995 break;
4996 default:
4997 abort();
4998 }
4999 fmt_ret = asprintf(&chunk_path,
5000 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5001 session_get_base_path(session),
5002 session->last_archived_chunk_name);
5003 if (fmt_ret == -1) {
5004 PERROR("Failed to format the path of the last archived trace chunk");
5005 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5006 cmd_ret = LTTNG_ERR_UNK;
5007 goto end;
5008 }
5009
5010 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5011 chunk_path, current_tracing_path_reply_len);
5012 free(chunk_path);
5013 if (fmt_ret) {
5014 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5015 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5016 cmd_ret = LTTNG_ERR_UNK;
5017 goto end;
5018 }
5019
5020 break;
5021 }
5022 case LTTNG_ROTATION_STATE_ERROR:
5023 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5024 rotation_id, session->name);
5025 break;
5026 default:
5027 abort();
5028 }
5029
5030 cmd_ret = LTTNG_OK;
5031 end:
5032 info_return->status = (int32_t) rotation_state;
5033 return cmd_ret;
5034 }
5035
5036 /*
5037 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5038 *
5039 * Configure the automatic rotation parameters.
5040 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5041 * 'activate' to false means deactivate the rotation schedule and validate that
5042 * 'new_value' has the same value as the currently active value.
5043 *
5044 * Return 0 on success or else a positive LTTNG_ERR code.
5045 */
5046 int cmd_rotation_set_schedule(struct ltt_session *session,
5047 bool activate, enum lttng_rotation_schedule_type schedule_type,
5048 uint64_t new_value,
5049 struct notification_thread_handle *notification_thread_handle)
5050 {
5051 int ret;
5052 uint64_t *parameter_value;
5053
5054 assert(session);
5055
5056 DBG("Cmd rotate set schedule session %s", session->name);
5057
5058 if (session->live_timer || !session->output_traces) {
5059 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5060 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5061 goto end;
5062 }
5063
5064 switch (schedule_type) {
5065 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5066 parameter_value = &session->rotate_size;
5067 break;
5068 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5069 parameter_value = &session->rotate_timer_period;
5070 if (new_value >= UINT_MAX) {
5071 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5072 new_value, UINT_MAX);
5073 ret = LTTNG_ERR_INVALID;
5074 goto end;
5075 }
5076 break;
5077 default:
5078 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5079 ret = LTTNG_ERR_INVALID;
5080 goto end;
5081 }
5082
5083 /* Improper use of the API. */
5084 if (new_value == -1ULL) {
5085 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5086 ret = LTTNG_ERR_INVALID;
5087 goto end;
5088 }
5089
5090 /*
5091 * As indicated in struct ltt_session's comments, a value of == 0 means
5092 * this schedule rotation type is not in use.
5093 *
5094 * Reject the command if we were asked to activate a schedule that was
5095 * already active.
5096 */
5097 if (activate && *parameter_value != 0) {
5098 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5099 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5100 goto end;
5101 }
5102
5103 /*
5104 * Reject the command if we were asked to deactivate a schedule that was
5105 * not active.
5106 */
5107 if (!activate && *parameter_value == 0) {
5108 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5109 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5110 goto end;
5111 }
5112
5113 /*
5114 * Reject the command if we were asked to deactivate a schedule that
5115 * doesn't exist.
5116 */
5117 if (!activate && *parameter_value != new_value) {
5118 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5119 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5120 goto end;
5121 }
5122
5123 *parameter_value = activate ? new_value : 0;
5124
5125 switch (schedule_type) {
5126 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5127 if (activate && session->active) {
5128 /*
5129 * Only start the timer if the session is active,
5130 * otherwise it will be started when the session starts.
5131 */
5132 ret = timer_session_rotation_schedule_timer_start(
5133 session, new_value);
5134 if (ret) {
5135 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5136 ret = LTTNG_ERR_UNK;
5137 goto end;
5138 }
5139 } else {
5140 ret = timer_session_rotation_schedule_timer_stop(
5141 session);
5142 if (ret) {
5143 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5144 ret = LTTNG_ERR_UNK;
5145 goto end;
5146 }
5147 }
5148 break;
5149 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5150 if (activate) {
5151 ret = subscribe_session_consumed_size_rotation(session,
5152 new_value, notification_thread_handle);
5153 if (ret) {
5154 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5155 ret = LTTNG_ERR_UNK;
5156 goto end;
5157 }
5158 } else {
5159 ret = unsubscribe_session_consumed_size_rotation(session,
5160 notification_thread_handle);
5161 if (ret) {
5162 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5163 ret = LTTNG_ERR_UNK;
5164 goto end;
5165 }
5166
5167 }
5168 break;
5169 default:
5170 /* Would have been caught before. */
5171 abort();
5172 }
5173
5174 ret = LTTNG_OK;
5175
5176 goto end;
5177
5178 end:
5179 return ret;
5180 }
5181
5182 /* Wait for a given path to be removed before continuing. */
5183 static enum lttng_error_code wait_on_path(void *path_data)
5184 {
5185 const char *shm_path = path_data;
5186
5187 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5188 shm_path);
5189 while (true) {
5190 int ret;
5191 struct stat st;
5192
5193 ret = stat(shm_path, &st);
5194 if (ret) {
5195 if (errno != ENOENT) {
5196 PERROR("stat() returned an error while checking for the existence of the shm path");
5197 } else {
5198 DBG("shm path no longer exists, completing the destruction of session");
5199 }
5200 break;
5201 } else {
5202 if (!S_ISDIR(st.st_mode)) {
5203 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5204 shm_path);
5205 break;
5206 }
5207 }
5208 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5209 }
5210 return LTTNG_OK;
5211 }
5212
5213 /*
5214 * Returns a pointer to a handler to run on completion of a command.
5215 * Returns NULL if no handler has to be run for the last command executed.
5216 */
5217 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5218 {
5219 struct cmd_completion_handler *handler = current_completion_handler;
5220
5221 current_completion_handler = NULL;
5222 return handler;
5223 }
5224
5225 /*
5226 * Init command subsystem.
5227 */
5228 void cmd_init(void)
5229 {
5230 /*
5231 * Set network sequence index to 1 for streams to match a relayd
5232 * socket on the consumer side.
5233 */
5234 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5235 relayd_net_seq_idx = 1;
5236 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5237
5238 DBG("Command subsystem initialized");
5239 }
LTTng tools - Deliverables
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