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relayd: Retrieve a relay_session's trace chunk on creation
[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 int session_live_timer,
1042 const uint64_t *current_chunk_id)
1043 {
1044 int ret;
1045 struct lttcomm_relayd_sock *rsock = NULL;
1046 enum lttng_error_code status;
1047
1048 /* Connect to relayd and make version check if uri is the control. */
1049 status = create_connect_relayd(relayd_uri, &rsock, consumer);
1050 if (status != LTTNG_OK) {
1051 goto relayd_comm_error;
1052 }
1053 assert(rsock);
1054
1055 /* Set the network sequence index if not set. */
1056 if (consumer->net_seq_index == (uint64_t) -1ULL) {
1057 pthread_mutex_lock(&relayd_net_seq_idx_lock);
1058 /*
1059 * Increment net_seq_idx because we are about to transfer the
1060 * new relayd socket to the consumer.
1061 * Assign unique key so the consumer can match streams.
1062 */
1063 consumer->net_seq_index = ++relayd_net_seq_idx;
1064 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
1065 }
1066
1067 /* Send relayd socket to consumer. */
1068 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
1069 relayd_uri->stype, session_id,
1070 session_name, hostname, session_live_timer,
1071 current_chunk_id);
1072 if (ret < 0) {
1073 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
1074 goto close_sock;
1075 }
1076
1077 /* Flag that the corresponding socket was sent. */
1078 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
1079 consumer_sock->control_sock_sent = 1;
1080 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
1081 consumer_sock->data_sock_sent = 1;
1082 }
1083
1084 /*
1085 * Close socket which was dup on the consumer side. The session daemon does
1086 * NOT keep track of the relayd socket(s) once transfer to the consumer.
1087 */
1088
1089 close_sock:
1090 if (status != LTTNG_OK) {
1091 /*
1092 * The consumer output for this session should not be used anymore
1093 * since the relayd connection failed thus making any tracing or/and
1094 * streaming not usable.
1095 */
1096 consumer->enabled = 0;
1097 }
1098 (void) relayd_close(rsock);
1099 free(rsock);
1100
1101 relayd_comm_error:
1102 return status;
1103 }
1104
1105 /*
1106 * Send both relayd sockets to a specific consumer and domain. This is a
1107 * helper function to facilitate sending the information to the consumer for a
1108 * session.
1109 *
1110 * The consumer socket lock must be held by the caller.
1111 *
1112 * Returns LTTNG_OK, or an LTTng error code on failure.
1113 */
1114 static enum lttng_error_code send_consumer_relayd_sockets(
1115 enum lttng_domain_type domain,
1116 unsigned int session_id, struct consumer_output *consumer,
1117 struct consumer_socket *sock, const char *session_name,
1118 const char *hostname, int session_live_timer,
1119 const uint64_t *current_chunk_id)
1120 {
1121 enum lttng_error_code status = LTTNG_OK;
1122
1123 assert(consumer);
1124 assert(sock);
1125
1126 /* Sending control relayd socket. */
1127 if (!sock->control_sock_sent) {
1128 status = send_consumer_relayd_socket(session_id,
1129 &consumer->dst.net.control, consumer, sock,
1130 session_name, hostname, session_live_timer,
1131 current_chunk_id);
1132 if (status != LTTNG_OK) {
1133 goto error;
1134 }
1135 }
1136
1137 /* Sending data relayd socket. */
1138 if (!sock->data_sock_sent) {
1139 status = send_consumer_relayd_socket(session_id,
1140 &consumer->dst.net.data, consumer, sock,
1141 session_name, hostname, session_live_timer,
1142 current_chunk_id);
1143 if (status != LTTNG_OK) {
1144 goto error;
1145 }
1146 }
1147
1148 error:
1149 return status;
1150 }
1151
1152 /*
1153 * Setup relayd connections for a tracing session. First creates the socket to
1154 * the relayd and send them to the right domain consumer. Consumer type MUST be
1155 * network.
1156 */
1157 int cmd_setup_relayd(struct ltt_session *session)
1158 {
1159 int ret = LTTNG_OK;
1160 struct ltt_ust_session *usess;
1161 struct ltt_kernel_session *ksess;
1162 struct consumer_socket *socket;
1163 struct lttng_ht_iter iter;
1164 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1165
1166 assert(session);
1167
1168 usess = session->ust_session;
1169 ksess = session->kernel_session;
1170
1171 DBG("Setting relayd for session %s", session->name);
1172
1173 if (session->current_trace_chunk) {
1174 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1175 session->current_trace_chunk, &current_chunk_id.value);
1176
1177 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1178 current_chunk_id.is_set = true;
1179 } else {
1180 ERR("Failed to get current trace chunk id");
1181 ret = LTTNG_ERR_UNK;
1182 goto error;
1183 }
1184 }
1185
1186 rcu_read_lock();
1187
1188 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1189 && usess->consumer->enabled) {
1190 /* For each consumer socket, send relayd sockets */
1191 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1192 socket, node.node) {
1193 pthread_mutex_lock(socket->lock);
1194 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1195 usess->consumer, socket,
1196 session->name, session->hostname,
1197 session->live_timer,
1198 current_chunk_id.is_set ? &current_chunk_id.value : NULL);
1199 pthread_mutex_unlock(socket->lock);
1200 if (ret != LTTNG_OK) {
1201 goto error;
1202 }
1203 /* Session is now ready for network streaming. */
1204 session->net_handle = 1;
1205 }
1206 session->consumer->relay_major_version =
1207 usess->consumer->relay_major_version;
1208 session->consumer->relay_minor_version =
1209 usess->consumer->relay_minor_version;
1210 }
1211
1212 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1213 && ksess->consumer->enabled) {
1214 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1215 socket, node.node) {
1216 pthread_mutex_lock(socket->lock);
1217 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1218 ksess->consumer, socket,
1219 session->name, session->hostname,
1220 session->live_timer,
1221 current_chunk_id.is_set ? &current_chunk_id.value : NULL);
1222 pthread_mutex_unlock(socket->lock);
1223 if (ret != LTTNG_OK) {
1224 goto error;
1225 }
1226 /* Session is now ready for network streaming. */
1227 session->net_handle = 1;
1228 }
1229 session->consumer->relay_major_version =
1230 ksess->consumer->relay_major_version;
1231 session->consumer->relay_minor_version =
1232 ksess->consumer->relay_minor_version;
1233 }
1234
1235 error:
1236 rcu_read_unlock();
1237 return ret;
1238 }
1239
1240 /*
1241 * Start a kernel session by opening all necessary streams.
1242 */
1243 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1244 {
1245 int ret;
1246 struct ltt_kernel_channel *kchan;
1247
1248 /* Open kernel metadata */
1249 if (ksess->metadata == NULL && ksess->output_traces) {
1250 ret = kernel_open_metadata(ksess);
1251 if (ret < 0) {
1252 ret = LTTNG_ERR_KERN_META_FAIL;
1253 goto error;
1254 }
1255 }
1256
1257 /* Open kernel metadata stream */
1258 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1259 ret = kernel_open_metadata_stream(ksess);
1260 if (ret < 0) {
1261 ERR("Kernel create metadata stream failed");
1262 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1263 goto error;
1264 }
1265 }
1266
1267 /* For each channel */
1268 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1269 if (kchan->stream_count == 0) {
1270 ret = kernel_open_channel_stream(kchan);
1271 if (ret < 0) {
1272 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1273 goto error;
1274 }
1275 /* Update the stream global counter */
1276 ksess->stream_count_global += ret;
1277 }
1278 }
1279
1280 /* Setup kernel consumer socket and send fds to it */
1281 ret = init_kernel_tracing(ksess);
1282 if (ret != 0) {
1283 ret = LTTNG_ERR_KERN_START_FAIL;
1284 goto error;
1285 }
1286
1287 /* This start the kernel tracing */
1288 ret = kernel_start_session(ksess);
1289 if (ret < 0) {
1290 ret = LTTNG_ERR_KERN_START_FAIL;
1291 goto error;
1292 }
1293
1294 /* Quiescent wait after starting trace */
1295 kernel_wait_quiescent(wpipe);
1296
1297 ksess->active = 1;
1298
1299 ret = LTTNG_OK;
1300
1301 error:
1302 return ret;
1303 }
1304
1305 /*
1306 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1307 */
1308 int cmd_disable_channel(struct ltt_session *session,
1309 enum lttng_domain_type domain, char *channel_name)
1310 {
1311 int ret;
1312 struct ltt_ust_session *usess;
1313
1314 usess = session->ust_session;
1315
1316 rcu_read_lock();
1317
1318 switch (domain) {
1319 case LTTNG_DOMAIN_KERNEL:
1320 {
1321 ret = channel_kernel_disable(session->kernel_session,
1322 channel_name);
1323 if (ret != LTTNG_OK) {
1324 goto error;
1325 }
1326
1327 kernel_wait_quiescent(kernel_tracer_fd);
1328 break;
1329 }
1330 case LTTNG_DOMAIN_UST:
1331 {
1332 struct ltt_ust_channel *uchan;
1333 struct lttng_ht *chan_ht;
1334
1335 chan_ht = usess->domain_global.channels;
1336
1337 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1338 if (uchan == NULL) {
1339 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1340 goto error;
1341 }
1342
1343 ret = channel_ust_disable(usess, uchan);
1344 if (ret != LTTNG_OK) {
1345 goto error;
1346 }
1347 break;
1348 }
1349 default:
1350 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1351 goto error;
1352 }
1353
1354 ret = LTTNG_OK;
1355
1356 error:
1357 rcu_read_unlock();
1358 return ret;
1359 }
1360
1361 /*
1362 * Command LTTNG_TRACK_PID processed by the client thread.
1363 *
1364 * Called with session lock held.
1365 */
1366 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1367 int pid)
1368 {
1369 int ret;
1370
1371 rcu_read_lock();
1372
1373 switch (domain) {
1374 case LTTNG_DOMAIN_KERNEL:
1375 {
1376 struct ltt_kernel_session *ksess;
1377
1378 ksess = session->kernel_session;
1379
1380 ret = kernel_track_pid(ksess, pid);
1381 if (ret != LTTNG_OK) {
1382 goto error;
1383 }
1384
1385 kernel_wait_quiescent(kernel_tracer_fd);
1386 break;
1387 }
1388 case LTTNG_DOMAIN_UST:
1389 {
1390 struct ltt_ust_session *usess;
1391
1392 usess = session->ust_session;
1393
1394 ret = trace_ust_track_pid(usess, pid);
1395 if (ret != LTTNG_OK) {
1396 goto error;
1397 }
1398 break;
1399 }
1400 default:
1401 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1402 goto error;
1403 }
1404
1405 ret = LTTNG_OK;
1406
1407 error:
1408 rcu_read_unlock();
1409 return ret;
1410 }
1411
1412 /*
1413 * Command LTTNG_UNTRACK_PID processed by the client thread.
1414 *
1415 * Called with session lock held.
1416 */
1417 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1418 int pid)
1419 {
1420 int ret;
1421
1422 rcu_read_lock();
1423
1424 switch (domain) {
1425 case LTTNG_DOMAIN_KERNEL:
1426 {
1427 struct ltt_kernel_session *ksess;
1428
1429 ksess = session->kernel_session;
1430
1431 ret = kernel_untrack_pid(ksess, pid);
1432 if (ret != LTTNG_OK) {
1433 goto error;
1434 }
1435
1436 kernel_wait_quiescent(kernel_tracer_fd);
1437 break;
1438 }
1439 case LTTNG_DOMAIN_UST:
1440 {
1441 struct ltt_ust_session *usess;
1442
1443 usess = session->ust_session;
1444
1445 ret = trace_ust_untrack_pid(usess, pid);
1446 if (ret != LTTNG_OK) {
1447 goto error;
1448 }
1449 break;
1450 }
1451 default:
1452 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1453 goto error;
1454 }
1455
1456 ret = LTTNG_OK;
1457
1458 error:
1459 rcu_read_unlock();
1460 return ret;
1461 }
1462
1463 /*
1464 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1465 *
1466 * The wpipe arguments is used as a notifier for the kernel thread.
1467 */
1468 int cmd_enable_channel(struct ltt_session *session,
1469 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1470 {
1471 int ret;
1472 struct ltt_ust_session *usess = session->ust_session;
1473 struct lttng_ht *chan_ht;
1474 size_t len;
1475
1476 assert(session);
1477 assert(attr);
1478 assert(domain);
1479
1480 len = lttng_strnlen(attr->name, sizeof(attr->name));
1481
1482 /* Validate channel name */
1483 if (attr->name[0] == '.' ||
1484 memchr(attr->name, '/', len) != NULL) {
1485 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1486 goto end;
1487 }
1488
1489 DBG("Enabling channel %s for session %s", attr->name, session->name);
1490
1491 rcu_read_lock();
1492
1493 /*
1494 * Don't try to enable a channel if the session has been started at
1495 * some point in time before. The tracer does not allow it.
1496 */
1497 if (session->has_been_started) {
1498 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1499 goto error;
1500 }
1501
1502 /*
1503 * If the session is a live session, remove the switch timer, the
1504 * live timer does the same thing but sends also synchronisation
1505 * beacons for inactive streams.
1506 */
1507 if (session->live_timer > 0) {
1508 attr->attr.live_timer_interval = session->live_timer;
1509 attr->attr.switch_timer_interval = 0;
1510 }
1511
1512 /* Check for feature support */
1513 switch (domain->type) {
1514 case LTTNG_DOMAIN_KERNEL:
1515 {
1516 if (kernel_supports_ring_buffer_snapshot_sample_positions(kernel_tracer_fd) != 1) {
1517 /* Sampling position of buffer is not supported */
1518 WARN("Kernel tracer does not support buffer monitoring. "
1519 "Setting the monitor interval timer to 0 "
1520 "(disabled) for channel '%s' of session '%s'",
1521 attr-> name, session->name);
1522 lttng_channel_set_monitor_timer_interval(attr, 0);
1523 }
1524 break;
1525 }
1526 case LTTNG_DOMAIN_UST:
1527 break;
1528 case LTTNG_DOMAIN_JUL:
1529 case LTTNG_DOMAIN_LOG4J:
1530 case LTTNG_DOMAIN_PYTHON:
1531 if (!agent_tracing_is_enabled()) {
1532 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1533 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1534 goto error;
1535 }
1536 break;
1537 default:
1538 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1539 goto error;
1540 }
1541
1542 switch (domain->type) {
1543 case LTTNG_DOMAIN_KERNEL:
1544 {
1545 struct ltt_kernel_channel *kchan;
1546
1547 kchan = trace_kernel_get_channel_by_name(attr->name,
1548 session->kernel_session);
1549 if (kchan == NULL) {
1550 if (session->snapshot.nb_output > 0 ||
1551 session->snapshot_mode) {
1552 /* Enforce mmap output for snapshot sessions. */
1553 attr->attr.output = LTTNG_EVENT_MMAP;
1554 }
1555 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1556 if (attr->name[0] != '\0') {
1557 session->kernel_session->has_non_default_channel = 1;
1558 }
1559 } else {
1560 ret = channel_kernel_enable(session->kernel_session, kchan);
1561 }
1562
1563 if (ret != LTTNG_OK) {
1564 goto error;
1565 }
1566
1567 kernel_wait_quiescent(kernel_tracer_fd);
1568 break;
1569 }
1570 case LTTNG_DOMAIN_UST:
1571 case LTTNG_DOMAIN_JUL:
1572 case LTTNG_DOMAIN_LOG4J:
1573 case LTTNG_DOMAIN_PYTHON:
1574 {
1575 struct ltt_ust_channel *uchan;
1576
1577 /*
1578 * FIXME
1579 *
1580 * Current agent implementation limitations force us to allow
1581 * only one channel at once in "agent" subdomains. Each
1582 * subdomain has a default channel name which must be strictly
1583 * adhered to.
1584 */
1585 if (domain->type == LTTNG_DOMAIN_JUL) {
1586 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1587 LTTNG_SYMBOL_NAME_LEN)) {
1588 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1589 goto error;
1590 }
1591 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1592 if (strncmp(attr->name, DEFAULT_LOG4J_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_PYTHON) {
1598 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1599 LTTNG_SYMBOL_NAME_LEN)) {
1600 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1601 goto error;
1602 }
1603 }
1604
1605 chan_ht = usess->domain_global.channels;
1606
1607 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1608 if (uchan == NULL) {
1609 ret = channel_ust_create(usess, attr, domain->buf_type);
1610 if (attr->name[0] != '\0') {
1611 usess->has_non_default_channel = 1;
1612 }
1613 } else {
1614 ret = channel_ust_enable(usess, uchan);
1615 }
1616 break;
1617 }
1618 default:
1619 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1620 goto error;
1621 }
1622
1623 if (ret == LTTNG_OK && attr->attr.output != LTTNG_EVENT_MMAP) {
1624 session->has_non_mmap_channel = true;
1625 }
1626 error:
1627 rcu_read_unlock();
1628 end:
1629 return ret;
1630 }
1631
1632 /*
1633 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1634 */
1635 int cmd_disable_event(struct ltt_session *session,
1636 enum lttng_domain_type domain, char *channel_name,
1637 struct lttng_event *event)
1638 {
1639 int ret;
1640 char *event_name;
1641
1642 DBG("Disable event command for event \'%s\'", event->name);
1643
1644 event_name = event->name;
1645
1646 /* Error out on unhandled search criteria */
1647 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1648 || event->pid || event->filter || event->exclusion) {
1649 ret = LTTNG_ERR_UNK;
1650 goto error;
1651 }
1652
1653 rcu_read_lock();
1654
1655 switch (domain) {
1656 case LTTNG_DOMAIN_KERNEL:
1657 {
1658 struct ltt_kernel_channel *kchan;
1659 struct ltt_kernel_session *ksess;
1660
1661 ksess = session->kernel_session;
1662
1663 /*
1664 * If a non-default channel has been created in the
1665 * session, explicitely require that -c chan_name needs
1666 * to be provided.
1667 */
1668 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1669 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1670 goto error_unlock;
1671 }
1672
1673 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1674 if (kchan == NULL) {
1675 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1676 goto error_unlock;
1677 }
1678
1679 switch (event->type) {
1680 case LTTNG_EVENT_ALL:
1681 case LTTNG_EVENT_TRACEPOINT:
1682 case LTTNG_EVENT_SYSCALL:
1683 case LTTNG_EVENT_PROBE:
1684 case LTTNG_EVENT_FUNCTION:
1685 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1686 if (event_name[0] == '\0') {
1687 ret = event_kernel_disable_event(kchan,
1688 NULL, event->type);
1689 } else {
1690 ret = event_kernel_disable_event(kchan,
1691 event_name, event->type);
1692 }
1693 if (ret != LTTNG_OK) {
1694 goto error_unlock;
1695 }
1696 break;
1697 default:
1698 ret = LTTNG_ERR_UNK;
1699 goto error_unlock;
1700 }
1701
1702 kernel_wait_quiescent(kernel_tracer_fd);
1703 break;
1704 }
1705 case LTTNG_DOMAIN_UST:
1706 {
1707 struct ltt_ust_channel *uchan;
1708 struct ltt_ust_session *usess;
1709
1710 usess = session->ust_session;
1711
1712 if (validate_ust_event_name(event_name)) {
1713 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1714 goto error_unlock;
1715 }
1716
1717 /*
1718 * If a non-default channel has been created in the
1719 * session, explicitly require that -c chan_name needs
1720 * to be provided.
1721 */
1722 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1723 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1724 goto error_unlock;
1725 }
1726
1727 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1728 channel_name);
1729 if (uchan == NULL) {
1730 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1731 goto error_unlock;
1732 }
1733
1734 switch (event->type) {
1735 case LTTNG_EVENT_ALL:
1736 /*
1737 * An empty event name means that everything
1738 * should be disabled.
1739 */
1740 if (event->name[0] == '\0') {
1741 ret = event_ust_disable_all_tracepoints(usess, uchan);
1742 } else {
1743 ret = event_ust_disable_tracepoint(usess, uchan,
1744 event_name);
1745 }
1746 if (ret != LTTNG_OK) {
1747 goto error_unlock;
1748 }
1749 break;
1750 default:
1751 ret = LTTNG_ERR_UNK;
1752 goto error_unlock;
1753 }
1754
1755 DBG3("Disable UST event %s in channel %s completed", event_name,
1756 channel_name);
1757 break;
1758 }
1759 case LTTNG_DOMAIN_LOG4J:
1760 case LTTNG_DOMAIN_JUL:
1761 case LTTNG_DOMAIN_PYTHON:
1762 {
1763 struct agent *agt;
1764 struct ltt_ust_session *usess = session->ust_session;
1765
1766 assert(usess);
1767
1768 switch (event->type) {
1769 case LTTNG_EVENT_ALL:
1770 break;
1771 default:
1772 ret = LTTNG_ERR_UNK;
1773 goto error_unlock;
1774 }
1775
1776 agt = trace_ust_find_agent(usess, domain);
1777 if (!agt) {
1778 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1779 goto error_unlock;
1780 }
1781 /*
1782 * An empty event name means that everything
1783 * should be disabled.
1784 */
1785 if (event->name[0] == '\0') {
1786 ret = event_agent_disable_all(usess, agt);
1787 } else {
1788 ret = event_agent_disable(usess, agt, event_name);
1789 }
1790 if (ret != LTTNG_OK) {
1791 goto error_unlock;
1792 }
1793
1794 break;
1795 }
1796 default:
1797 ret = LTTNG_ERR_UND;
1798 goto error_unlock;
1799 }
1800
1801 ret = LTTNG_OK;
1802
1803 error_unlock:
1804 rcu_read_unlock();
1805 error:
1806 return ret;
1807 }
1808
1809 /*
1810 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1811 */
1812 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1813 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1814 {
1815 int ret, chan_kern_created = 0, chan_ust_created = 0;
1816 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1817
1818 /*
1819 * Don't try to add a context if the session has been started at
1820 * some point in time before. The tracer does not allow it and would
1821 * result in a corrupted trace.
1822 */
1823 if (session->has_been_started) {
1824 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1825 goto end;
1826 }
1827
1828 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1829 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1830 app_ctx_name = ctx->u.app_ctx.ctx_name;
1831 }
1832
1833 switch (domain) {
1834 case LTTNG_DOMAIN_KERNEL:
1835 assert(session->kernel_session);
1836
1837 if (session->kernel_session->channel_count == 0) {
1838 /* Create default channel */
1839 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1840 if (ret != LTTNG_OK) {
1841 goto error;
1842 }
1843 chan_kern_created = 1;
1844 }
1845 /* Add kernel context to kernel tracer */
1846 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1847 if (ret != LTTNG_OK) {
1848 goto error;
1849 }
1850 break;
1851 case LTTNG_DOMAIN_JUL:
1852 case LTTNG_DOMAIN_LOG4J:
1853 {
1854 /*
1855 * Validate channel name.
1856 * If no channel name is given and the domain is JUL or LOG4J,
1857 * set it to the appropriate domain-specific channel name. If
1858 * a name is provided but does not match the expexted channel
1859 * name, return an error.
1860 */
1861 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1862 strcmp(channel_name,
1863 DEFAULT_JUL_CHANNEL_NAME)) {
1864 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1865 goto error;
1866 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1867 strcmp(channel_name,
1868 DEFAULT_LOG4J_CHANNEL_NAME)) {
1869 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1870 goto error;
1871 }
1872 /* break is _not_ missing here. */
1873 }
1874 case LTTNG_DOMAIN_UST:
1875 {
1876 struct ltt_ust_session *usess = session->ust_session;
1877 unsigned int chan_count;
1878
1879 assert(usess);
1880
1881 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1882 if (chan_count == 0) {
1883 struct lttng_channel *attr;
1884 /* Create default channel */
1885 attr = channel_new_default_attr(domain, usess->buffer_type);
1886 if (attr == NULL) {
1887 ret = LTTNG_ERR_FATAL;
1888 goto error;
1889 }
1890
1891 ret = channel_ust_create(usess, attr, usess->buffer_type);
1892 if (ret != LTTNG_OK) {
1893 free(attr);
1894 goto error;
1895 }
1896 channel_attr_destroy(attr);
1897 chan_ust_created = 1;
1898 }
1899
1900 ret = context_ust_add(usess, domain, ctx, channel_name);
1901 free(app_ctx_provider_name);
1902 free(app_ctx_name);
1903 app_ctx_name = NULL;
1904 app_ctx_provider_name = NULL;
1905 if (ret != LTTNG_OK) {
1906 goto error;
1907 }
1908 break;
1909 }
1910 default:
1911 ret = LTTNG_ERR_UND;
1912 goto error;
1913 }
1914
1915 ret = LTTNG_OK;
1916 goto end;
1917
1918 error:
1919 if (chan_kern_created) {
1920 struct ltt_kernel_channel *kchan =
1921 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1922 session->kernel_session);
1923 /* Created previously, this should NOT fail. */
1924 assert(kchan);
1925 kernel_destroy_channel(kchan);
1926 }
1927
1928 if (chan_ust_created) {
1929 struct ltt_ust_channel *uchan =
1930 trace_ust_find_channel_by_name(
1931 session->ust_session->domain_global.channels,
1932 DEFAULT_CHANNEL_NAME);
1933 /* Created previously, this should NOT fail. */
1934 assert(uchan);
1935 /* Remove from the channel list of the session. */
1936 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1937 uchan);
1938 trace_ust_destroy_channel(uchan);
1939 }
1940 end:
1941 free(app_ctx_provider_name);
1942 free(app_ctx_name);
1943 return ret;
1944 }
1945
1946 static inline bool name_starts_with(const char *name, const char *prefix)
1947 {
1948 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1949
1950 return !strncmp(name, prefix, max_cmp_len);
1951 }
1952
1953 /* Perform userspace-specific event name validation */
1954 static int validate_ust_event_name(const char *name)
1955 {
1956 int ret = 0;
1957
1958 if (!name) {
1959 ret = -1;
1960 goto end;
1961 }
1962
1963 /*
1964 * Check name against all internal UST event component namespaces used
1965 * by the agents.
1966 */
1967 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1968 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1969 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1970 ret = -1;
1971 }
1972
1973 end:
1974 return ret;
1975 }
1976
1977 /*
1978 * Internal version of cmd_enable_event() with a supplemental
1979 * "internal_event" flag which is used to enable internal events which should
1980 * be hidden from clients. Such events are used in the agent implementation to
1981 * enable the events through which all "agent" events are funeled.
1982 */
1983 static int _cmd_enable_event(struct ltt_session *session,
1984 struct lttng_domain *domain,
1985 char *channel_name, struct lttng_event *event,
1986 char *filter_expression,
1987 struct lttng_filter_bytecode *filter,
1988 struct lttng_event_exclusion *exclusion,
1989 int wpipe, bool internal_event)
1990 {
1991 int ret = 0, channel_created = 0;
1992 struct lttng_channel *attr = NULL;
1993
1994 assert(session);
1995 assert(event);
1996 assert(channel_name);
1997
1998 /* If we have a filter, we must have its filter expression */
1999 assert(!(!!filter_expression ^ !!filter));
2000
2001 /* Normalize event name as a globbing pattern */
2002 strutils_normalize_star_glob_pattern(event->name);
2003
2004 /* Normalize exclusion names as globbing patterns */
2005 if (exclusion) {
2006 size_t i;
2007
2008 for (i = 0; i < exclusion->count; i++) {
2009 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2010
2011 strutils_normalize_star_glob_pattern(name);
2012 }
2013 }
2014
2015 DBG("Enable event command for event \'%s\'", event->name);
2016
2017 rcu_read_lock();
2018
2019 switch (domain->type) {
2020 case LTTNG_DOMAIN_KERNEL:
2021 {
2022 struct ltt_kernel_channel *kchan;
2023
2024 /*
2025 * If a non-default channel has been created in the
2026 * session, explicitely require that -c chan_name needs
2027 * to be provided.
2028 */
2029 if (session->kernel_session->has_non_default_channel
2030 && channel_name[0] == '\0') {
2031 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2032 goto error;
2033 }
2034
2035 kchan = trace_kernel_get_channel_by_name(channel_name,
2036 session->kernel_session);
2037 if (kchan == NULL) {
2038 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2039 LTTNG_BUFFER_GLOBAL);
2040 if (attr == NULL) {
2041 ret = LTTNG_ERR_FATAL;
2042 goto error;
2043 }
2044 if (lttng_strncpy(attr->name, channel_name,
2045 sizeof(attr->name))) {
2046 ret = LTTNG_ERR_INVALID;
2047 goto error;
2048 }
2049
2050 ret = cmd_enable_channel(session, domain, attr, wpipe);
2051 if (ret != LTTNG_OK) {
2052 goto error;
2053 }
2054 channel_created = 1;
2055 }
2056
2057 /* Get the newly created kernel channel pointer */
2058 kchan = trace_kernel_get_channel_by_name(channel_name,
2059 session->kernel_session);
2060 if (kchan == NULL) {
2061 /* This sould not happen... */
2062 ret = LTTNG_ERR_FATAL;
2063 goto error;
2064 }
2065
2066 switch (event->type) {
2067 case LTTNG_EVENT_ALL:
2068 {
2069 char *filter_expression_a = NULL;
2070 struct lttng_filter_bytecode *filter_a = NULL;
2071
2072 /*
2073 * We need to duplicate filter_expression and filter,
2074 * because ownership is passed to first enable
2075 * event.
2076 */
2077 if (filter_expression) {
2078 filter_expression_a = strdup(filter_expression);
2079 if (!filter_expression_a) {
2080 ret = LTTNG_ERR_FATAL;
2081 goto error;
2082 }
2083 }
2084 if (filter) {
2085 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2086 if (!filter_a) {
2087 free(filter_expression_a);
2088 ret = LTTNG_ERR_FATAL;
2089 goto error;
2090 }
2091 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2092 }
2093 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2094 ret = event_kernel_enable_event(kchan, event,
2095 filter_expression, filter);
2096 /* We have passed ownership */
2097 filter_expression = NULL;
2098 filter = NULL;
2099 if (ret != LTTNG_OK) {
2100 if (channel_created) {
2101 /* Let's not leak a useless channel. */
2102 kernel_destroy_channel(kchan);
2103 }
2104 free(filter_expression_a);
2105 free(filter_a);
2106 goto error;
2107 }
2108 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2109 ret = event_kernel_enable_event(kchan, event,
2110 filter_expression_a, filter_a);
2111 /* We have passed ownership */
2112 filter_expression_a = NULL;
2113 filter_a = NULL;
2114 if (ret != LTTNG_OK) {
2115 goto error;
2116 }
2117 break;
2118 }
2119 case LTTNG_EVENT_PROBE:
2120 case LTTNG_EVENT_USERSPACE_PROBE:
2121 case LTTNG_EVENT_FUNCTION:
2122 case LTTNG_EVENT_FUNCTION_ENTRY:
2123 case LTTNG_EVENT_TRACEPOINT:
2124 ret = event_kernel_enable_event(kchan, event,
2125 filter_expression, filter);
2126 /* We have passed ownership */
2127 filter_expression = NULL;
2128 filter = NULL;
2129 if (ret != LTTNG_OK) {
2130 if (channel_created) {
2131 /* Let's not leak a useless channel. */
2132 kernel_destroy_channel(kchan);
2133 }
2134 goto error;
2135 }
2136 break;
2137 case LTTNG_EVENT_SYSCALL:
2138 ret = event_kernel_enable_event(kchan, event,
2139 filter_expression, filter);
2140 /* We have passed ownership */
2141 filter_expression = NULL;
2142 filter = NULL;
2143 if (ret != LTTNG_OK) {
2144 goto error;
2145 }
2146 break;
2147 default:
2148 ret = LTTNG_ERR_UNK;
2149 goto error;
2150 }
2151
2152 kernel_wait_quiescent(kernel_tracer_fd);
2153 break;
2154 }
2155 case LTTNG_DOMAIN_UST:
2156 {
2157 struct ltt_ust_channel *uchan;
2158 struct ltt_ust_session *usess = session->ust_session;
2159
2160 assert(usess);
2161
2162 /*
2163 * If a non-default channel has been created in the
2164 * session, explicitely require that -c chan_name needs
2165 * to be provided.
2166 */
2167 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2168 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2169 goto error;
2170 }
2171
2172 /* Get channel from global UST domain */
2173 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2174 channel_name);
2175 if (uchan == NULL) {
2176 /* Create default channel */
2177 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2178 usess->buffer_type);
2179 if (attr == NULL) {
2180 ret = LTTNG_ERR_FATAL;
2181 goto error;
2182 }
2183 if (lttng_strncpy(attr->name, channel_name,
2184 sizeof(attr->name))) {
2185 ret = LTTNG_ERR_INVALID;
2186 goto error;
2187 }
2188
2189 ret = cmd_enable_channel(session, domain, attr, wpipe);
2190 if (ret != LTTNG_OK) {
2191 goto error;
2192 }
2193
2194 /* Get the newly created channel reference back */
2195 uchan = trace_ust_find_channel_by_name(
2196 usess->domain_global.channels, channel_name);
2197 assert(uchan);
2198 }
2199
2200 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2201 /*
2202 * Don't allow users to add UST events to channels which
2203 * are assigned to a userspace subdomain (JUL, Log4J,
2204 * Python, etc.).
2205 */
2206 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2207 goto error;
2208 }
2209
2210 if (!internal_event) {
2211 /*
2212 * Ensure the event name is not reserved for internal
2213 * use.
2214 */
2215 ret = validate_ust_event_name(event->name);
2216 if (ret) {
2217 WARN("Userspace event name %s failed validation.",
2218 event->name);
2219 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2220 goto error;
2221 }
2222 }
2223
2224 /* At this point, the session and channel exist on the tracer */
2225 ret = event_ust_enable_tracepoint(usess, uchan, event,
2226 filter_expression, filter, exclusion,
2227 internal_event);
2228 /* We have passed ownership */
2229 filter_expression = NULL;
2230 filter = NULL;
2231 exclusion = NULL;
2232 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2233 goto already_enabled;
2234 } else if (ret != LTTNG_OK) {
2235 goto error;
2236 }
2237 break;
2238 }
2239 case LTTNG_DOMAIN_LOG4J:
2240 case LTTNG_DOMAIN_JUL:
2241 case LTTNG_DOMAIN_PYTHON:
2242 {
2243 const char *default_event_name, *default_chan_name;
2244 struct agent *agt;
2245 struct lttng_event uevent;
2246 struct lttng_domain tmp_dom;
2247 struct ltt_ust_session *usess = session->ust_session;
2248
2249 assert(usess);
2250
2251 if (!agent_tracing_is_enabled()) {
2252 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2253 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2254 goto error;
2255 }
2256
2257 agt = trace_ust_find_agent(usess, domain->type);
2258 if (!agt) {
2259 agt = agent_create(domain->type);
2260 if (!agt) {
2261 ret = LTTNG_ERR_NOMEM;
2262 goto error;
2263 }
2264 agent_add(agt, usess->agents);
2265 }
2266
2267 /* Create the default tracepoint. */
2268 memset(&uevent, 0, sizeof(uevent));
2269 uevent.type = LTTNG_EVENT_TRACEPOINT;
2270 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2271 default_event_name = event_get_default_agent_ust_name(
2272 domain->type);
2273 if (!default_event_name) {
2274 ret = LTTNG_ERR_FATAL;
2275 goto error;
2276 }
2277 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2278 uevent.name[sizeof(uevent.name) - 1] = '\0';
2279
2280 /*
2281 * The domain type is changed because we are about to enable the
2282 * default channel and event for the JUL domain that are hardcoded.
2283 * This happens in the UST domain.
2284 */
2285 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2286 tmp_dom.type = LTTNG_DOMAIN_UST;
2287
2288 switch (domain->type) {
2289 case LTTNG_DOMAIN_LOG4J:
2290 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2291 break;
2292 case LTTNG_DOMAIN_JUL:
2293 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2294 break;
2295 case LTTNG_DOMAIN_PYTHON:
2296 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2297 break;
2298 default:
2299 /* The switch/case we are in makes this impossible */
2300 assert(0);
2301 }
2302
2303 {
2304 char *filter_expression_copy = NULL;
2305 struct lttng_filter_bytecode *filter_copy = NULL;
2306
2307 if (filter) {
2308 const size_t filter_size = sizeof(
2309 struct lttng_filter_bytecode)
2310 + filter->len;
2311
2312 filter_copy = zmalloc(filter_size);
2313 if (!filter_copy) {
2314 ret = LTTNG_ERR_NOMEM;
2315 goto error;
2316 }
2317 memcpy(filter_copy, filter, filter_size);
2318
2319 filter_expression_copy =
2320 strdup(filter_expression);
2321 if (!filter_expression) {
2322 ret = LTTNG_ERR_NOMEM;
2323 }
2324
2325 if (!filter_expression_copy || !filter_copy) {
2326 free(filter_expression_copy);
2327 free(filter_copy);
2328 goto error;
2329 }
2330 }
2331
2332 ret = cmd_enable_event_internal(session, &tmp_dom,
2333 (char *) default_chan_name,
2334 &uevent, filter_expression_copy,
2335 filter_copy, NULL, wpipe);
2336 }
2337
2338 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2339 goto already_enabled;
2340 } else if (ret != LTTNG_OK) {
2341 goto error;
2342 }
2343
2344 /* The wild card * means that everything should be enabled. */
2345 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2346 ret = event_agent_enable_all(usess, agt, event, filter,
2347 filter_expression);
2348 } else {
2349 ret = event_agent_enable(usess, agt, event, filter,
2350 filter_expression);
2351 }
2352 filter = NULL;
2353 filter_expression = NULL;
2354 if (ret != LTTNG_OK) {
2355 goto error;
2356 }
2357
2358 break;
2359 }
2360 default:
2361 ret = LTTNG_ERR_UND;
2362 goto error;
2363 }
2364
2365 ret = LTTNG_OK;
2366
2367 already_enabled:
2368 error:
2369 free(filter_expression);
2370 free(filter);
2371 free(exclusion);
2372 channel_attr_destroy(attr);
2373 rcu_read_unlock();
2374 return ret;
2375 }
2376
2377 /*
2378 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2379 * We own filter, exclusion, and filter_expression.
2380 */
2381 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
2382 char *channel_name, struct lttng_event *event,
2383 char *filter_expression,
2384 struct lttng_filter_bytecode *filter,
2385 struct lttng_event_exclusion *exclusion,
2386 int wpipe)
2387 {
2388 return _cmd_enable_event(session, domain, channel_name, event,
2389 filter_expression, filter, exclusion, wpipe, false);
2390 }
2391
2392 /*
2393 * Enable an event which is internal to LTTng. An internal should
2394 * never be made visible to clients and are immune to checks such as
2395 * reserved names.
2396 */
2397 static int cmd_enable_event_internal(struct ltt_session *session,
2398 struct lttng_domain *domain,
2399 char *channel_name, struct lttng_event *event,
2400 char *filter_expression,
2401 struct lttng_filter_bytecode *filter,
2402 struct lttng_event_exclusion *exclusion,
2403 int wpipe)
2404 {
2405 return _cmd_enable_event(session, domain, channel_name, event,
2406 filter_expression, filter, exclusion, wpipe, true);
2407 }
2408
2409 /*
2410 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2411 */
2412 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2413 struct lttng_event **events)
2414 {
2415 int ret;
2416 ssize_t nb_events = 0;
2417
2418 switch (domain) {
2419 case LTTNG_DOMAIN_KERNEL:
2420 nb_events = kernel_list_events(kernel_tracer_fd, events);
2421 if (nb_events < 0) {
2422 ret = LTTNG_ERR_KERN_LIST_FAIL;
2423 goto error;
2424 }
2425 break;
2426 case LTTNG_DOMAIN_UST:
2427 nb_events = ust_app_list_events(events);
2428 if (nb_events < 0) {
2429 ret = LTTNG_ERR_UST_LIST_FAIL;
2430 goto error;
2431 }
2432 break;
2433 case LTTNG_DOMAIN_LOG4J:
2434 case LTTNG_DOMAIN_JUL:
2435 case LTTNG_DOMAIN_PYTHON:
2436 nb_events = agent_list_events(events, domain);
2437 if (nb_events < 0) {
2438 ret = LTTNG_ERR_UST_LIST_FAIL;
2439 goto error;
2440 }
2441 break;
2442 default:
2443 ret = LTTNG_ERR_UND;
2444 goto error;
2445 }
2446
2447 return nb_events;
2448
2449 error:
2450 /* Return negative value to differentiate return code */
2451 return -ret;
2452 }
2453
2454 /*
2455 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2456 */
2457 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2458 struct lttng_event_field **fields)
2459 {
2460 int ret;
2461 ssize_t nb_fields = 0;
2462
2463 switch (domain) {
2464 case LTTNG_DOMAIN_UST:
2465 nb_fields = ust_app_list_event_fields(fields);
2466 if (nb_fields < 0) {
2467 ret = LTTNG_ERR_UST_LIST_FAIL;
2468 goto error;
2469 }
2470 break;
2471 case LTTNG_DOMAIN_KERNEL:
2472 default: /* fall-through */
2473 ret = LTTNG_ERR_UND;
2474 goto error;
2475 }
2476
2477 return nb_fields;
2478
2479 error:
2480 /* Return negative value to differentiate return code */
2481 return -ret;
2482 }
2483
2484 ssize_t cmd_list_syscalls(struct lttng_event **events)
2485 {
2486 return syscall_table_list(events);
2487 }
2488
2489 /*
2490 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2491 *
2492 * Called with session lock held.
2493 */
2494 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2495 enum lttng_domain_type domain, int32_t **pids)
2496 {
2497 int ret;
2498 ssize_t nr_pids = 0;
2499
2500 switch (domain) {
2501 case LTTNG_DOMAIN_KERNEL:
2502 {
2503 struct ltt_kernel_session *ksess;
2504
2505 ksess = session->kernel_session;
2506 nr_pids = kernel_list_tracker_pids(ksess, pids);
2507 if (nr_pids < 0) {
2508 ret = LTTNG_ERR_KERN_LIST_FAIL;
2509 goto error;
2510 }
2511 break;
2512 }
2513 case LTTNG_DOMAIN_UST:
2514 {
2515 struct ltt_ust_session *usess;
2516
2517 usess = session->ust_session;
2518 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2519 if (nr_pids < 0) {
2520 ret = LTTNG_ERR_UST_LIST_FAIL;
2521 goto error;
2522 }
2523 break;
2524 }
2525 case LTTNG_DOMAIN_LOG4J:
2526 case LTTNG_DOMAIN_JUL:
2527 case LTTNG_DOMAIN_PYTHON:
2528 default:
2529 ret = LTTNG_ERR_UND;
2530 goto error;
2531 }
2532
2533 return nr_pids;
2534
2535 error:
2536 /* Return negative value to differentiate return code */
2537 return -ret;
2538 }
2539
2540 /*
2541 * Command LTTNG_START_TRACE processed by the client thread.
2542 *
2543 * Called with session mutex held.
2544 */
2545 int cmd_start_trace(struct ltt_session *session)
2546 {
2547 enum lttng_error_code ret;
2548 unsigned long nb_chan = 0;
2549 struct ltt_kernel_session *ksession;
2550 struct ltt_ust_session *usess;
2551
2552 assert(session);
2553
2554 /* Ease our life a bit ;) */
2555 ksession = session->kernel_session;
2556 usess = session->ust_session;
2557
2558 /* Is the session already started? */
2559 if (session->active) {
2560 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2561 goto error;
2562 }
2563
2564 /*
2565 * Starting a session without channel is useless since after that it's not
2566 * possible to enable channel thus inform the client.
2567 */
2568 if (usess && usess->domain_global.channels) {
2569 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2570 }
2571 if (ksession) {
2572 nb_chan += ksession->channel_count;
2573 }
2574 if (!nb_chan) {
2575 ret = LTTNG_ERR_NO_CHANNEL;
2576 goto error;
2577 }
2578
2579 if (session->output_traces && !session->current_trace_chunk) {
2580 struct lttng_trace_chunk *trace_chunk;
2581
2582 trace_chunk = session_create_new_trace_chunk(
2583 session, NULL, NULL);
2584 if (!trace_chunk) {
2585 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2586 goto error;
2587 }
2588 assert(!session->current_trace_chunk);
2589 ret = session_set_trace_chunk(session, trace_chunk, NULL);
2590 lttng_trace_chunk_put(trace_chunk);
2591 if (ret) {
2592 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2593 goto error;
2594 }
2595 }
2596
2597 /* Kernel tracing */
2598 if (ksession != NULL) {
2599 DBG("Start kernel tracing session %s", session->name);
2600 ret = start_kernel_session(ksession, kernel_tracer_fd);
2601 if (ret != LTTNG_OK) {
2602 goto error;
2603 }
2604 }
2605
2606 /* Flag session that trace should start automatically */
2607 if (usess) {
2608 int int_ret = ust_app_start_trace_all(usess);
2609
2610 if (int_ret < 0) {
2611 ret = LTTNG_ERR_UST_START_FAIL;
2612 goto error;
2613 }
2614 }
2615
2616 /* Flag this after a successful start. */
2617 session->has_been_started = 1;
2618 session->active = 1;
2619
2620 /*
2621 * Clear the flag that indicates that a rotation was done while the
2622 * session was stopped.
2623 */
2624 session->rotated_after_last_stop = false;
2625
2626 if (session->rotate_timer_period) {
2627 int int_ret = timer_session_rotation_schedule_timer_start(
2628 session, session->rotate_timer_period);
2629
2630 if (int_ret < 0) {
2631 ERR("Failed to enable rotate timer");
2632 ret = LTTNG_ERR_UNK;
2633 goto error;
2634 }
2635 }
2636
2637 ret = LTTNG_OK;
2638
2639 error:
2640 return ret;
2641 }
2642
2643 /*
2644 * Command LTTNG_STOP_TRACE processed by the client thread.
2645 */
2646 int cmd_stop_trace(struct ltt_session *session)
2647 {
2648 int ret;
2649 struct ltt_kernel_channel *kchan;
2650 struct ltt_kernel_session *ksession;
2651 struct ltt_ust_session *usess;
2652 bool error_occurred = false;
2653
2654 assert(session);
2655
2656 DBG("Begin stop session %s (id %" PRIu64 ")", session->name, session->id);
2657 /* Short cut */
2658 ksession = session->kernel_session;
2659 usess = session->ust_session;
2660
2661 /* Session is not active. Skip everythong and inform the client. */
2662 if (!session->active) {
2663 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2664 goto error;
2665 }
2666
2667 /* Kernel tracer */
2668 if (ksession && ksession->active) {
2669 DBG("Stop kernel tracing");
2670
2671 ret = kernel_stop_session(ksession);
2672 if (ret < 0) {
2673 ret = LTTNG_ERR_KERN_STOP_FAIL;
2674 goto error;
2675 }
2676
2677 kernel_wait_quiescent(kernel_tracer_fd);
2678
2679 /* Flush metadata after stopping (if exists) */
2680 if (ksession->metadata_stream_fd >= 0) {
2681 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2682 if (ret < 0) {
2683 ERR("Kernel metadata flush failed");
2684 }
2685 }
2686
2687 /* Flush all buffers after stopping */
2688 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2689 ret = kernel_flush_buffer(kchan);
2690 if (ret < 0) {
2691 ERR("Kernel flush buffer error");
2692 }
2693 }
2694
2695 ksession->active = 0;
2696 DBG("Kernel session stopped %s (id %" PRIu64 ")", session->name,
2697 session->id);
2698 }
2699
2700 if (usess && usess->active) {
2701 ret = ust_app_stop_trace_all(usess);
2702 if (ret < 0) {
2703 ret = LTTNG_ERR_UST_STOP_FAIL;
2704 goto error;
2705 }
2706 }
2707
2708 /* Flag inactive after a successful stop. */
2709 session->active = 0;
2710 ret = !error_occurred ? LTTNG_OK : LTTNG_ERR_UNK;
2711
2712 error:
2713 return ret;
2714 }
2715
2716 /*
2717 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2718 */
2719 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2720 struct lttng_uri *uris)
2721 {
2722 int ret, i;
2723 struct ltt_kernel_session *ksess = session->kernel_session;
2724 struct ltt_ust_session *usess = session->ust_session;
2725
2726 assert(session);
2727 assert(uris);
2728 assert(nb_uri > 0);
2729
2730 /* Can't set consumer URI if the session is active. */
2731 if (session->active) {
2732 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2733 goto error;
2734 }
2735
2736 /* Set the "global" consumer URIs */
2737 for (i = 0; i < nb_uri; i++) {
2738 ret = add_uri_to_consumer(session,
2739 session->consumer,
2740 &uris[i], LTTNG_DOMAIN_NONE);
2741 if (ret != LTTNG_OK) {
2742 goto error;
2743 }
2744 }
2745
2746 /* Set UST session URIs */
2747 if (session->ust_session) {
2748 for (i = 0; i < nb_uri; i++) {
2749 ret = add_uri_to_consumer(session,
2750 session->ust_session->consumer,
2751 &uris[i], LTTNG_DOMAIN_UST);
2752 if (ret != LTTNG_OK) {
2753 goto error;
2754 }
2755 }
2756 }
2757
2758 /* Set kernel session URIs */
2759 if (session->kernel_session) {
2760 for (i = 0; i < nb_uri; i++) {
2761 ret = add_uri_to_consumer(session,
2762 session->kernel_session->consumer,
2763 &uris[i], LTTNG_DOMAIN_KERNEL);
2764 if (ret != LTTNG_OK) {
2765 goto error;
2766 }
2767 }
2768 }
2769
2770 /*
2771 * Make sure to set the session in output mode after we set URI since a
2772 * session can be created without URL (thus flagged in no output mode).
2773 */
2774 session->output_traces = 1;
2775 if (ksess) {
2776 ksess->output_traces = 1;
2777 }
2778
2779 if (usess) {
2780 usess->output_traces = 1;
2781 }
2782
2783 /* All good! */
2784 ret = LTTNG_OK;
2785
2786 error:
2787 return ret;
2788 }
2789
2790 static
2791 enum lttng_error_code set_session_output_from_descriptor(
2792 struct ltt_session *session,
2793 const struct lttng_session_descriptor *descriptor)
2794 {
2795 int ret;
2796 enum lttng_error_code ret_code = LTTNG_OK;
2797 enum lttng_session_descriptor_type session_type =
2798 lttng_session_descriptor_get_type(descriptor);
2799 enum lttng_session_descriptor_output_type output_type =
2800 lttng_session_descriptor_get_output_type(descriptor);
2801 struct lttng_uri uris[2] = {};
2802 size_t uri_count = 0;
2803
2804 switch (output_type) {
2805 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
2806 goto end;
2807 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
2808 lttng_session_descriptor_get_local_output_uri(descriptor,
2809 &uris[0]);
2810 uri_count = 1;
2811 break;
2812 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
2813 lttng_session_descriptor_get_network_output_uris(descriptor,
2814 &uris[0], &uris[1]);
2815 uri_count = 2;
2816 break;
2817 default:
2818 ret_code = LTTNG_ERR_INVALID;
2819 goto end;
2820 }
2821
2822 switch (session_type) {
2823 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2824 {
2825 struct snapshot_output *new_output = NULL;
2826
2827 new_output = snapshot_output_alloc();
2828 if (!new_output) {
2829 ret_code = LTTNG_ERR_NOMEM;
2830 goto end;
2831 }
2832
2833 ret = snapshot_output_init_with_uri(session,
2834 DEFAULT_SNAPSHOT_MAX_SIZE,
2835 NULL, uris, uri_count, session->consumer,
2836 new_output, &session->snapshot);
2837 if (ret < 0) {
2838 ret_code = (ret == -ENOMEM) ?
2839 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
2840 snapshot_output_destroy(new_output);
2841 goto end;
2842 }
2843 snapshot_add_output(&session->snapshot, new_output);
2844 break;
2845 }
2846 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
2847 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
2848 {
2849 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
2850 break;
2851 }
2852 default:
2853 ret_code = LTTNG_ERR_INVALID;
2854 goto end;
2855 }
2856 end:
2857 return ret_code;
2858 }
2859
2860 static
2861 enum lttng_error_code cmd_create_session_from_descriptor(
2862 struct lttng_session_descriptor *descriptor,
2863 const lttng_sock_cred *creds,
2864 const char *home_path)
2865 {
2866 int ret;
2867 enum lttng_error_code ret_code;
2868 const char *session_name;
2869 struct ltt_session *new_session = NULL;
2870 enum lttng_session_descriptor_status descriptor_status;
2871
2872 session_lock_list();
2873 if (home_path) {
2874 if (*home_path != '/') {
2875 ERR("Home path provided by client is not absolute");
2876 ret_code = LTTNG_ERR_INVALID;
2877 goto end;
2878 }
2879 }
2880
2881 descriptor_status = lttng_session_descriptor_get_session_name(
2882 descriptor, &session_name);
2883 switch (descriptor_status) {
2884 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
2885 break;
2886 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
2887 session_name = NULL;
2888 break;
2889 default:
2890 ret_code = LTTNG_ERR_INVALID;
2891 goto end;
2892 }
2893 ret_code = session_create(session_name, creds->uid, creds->gid,
2894 &new_session);
2895 if (ret_code != LTTNG_OK) {
2896 goto end;
2897 }
2898
2899 if (!session_name) {
2900 ret = lttng_session_descriptor_set_session_name(descriptor,
2901 new_session->name);
2902 if (ret) {
2903 ret_code = LTTNG_ERR_SESSION_FAIL;
2904 goto end;
2905 }
2906 }
2907
2908 if (!lttng_session_descriptor_is_output_destination_initialized(
2909 descriptor)) {
2910 /*
2911 * Only include the session's creation time in the output
2912 * destination if the name of the session itself was
2913 * not auto-generated.
2914 */
2915 ret_code = lttng_session_descriptor_set_default_output(
2916 descriptor,
2917 session_name ? &new_session->creation_time : NULL,
2918 home_path);
2919 if (ret_code != LTTNG_OK) {
2920 goto end;
2921 }
2922 } else {
2923 new_session->has_user_specified_directory =
2924 lttng_session_descriptor_has_output_directory(
2925 descriptor);
2926 }
2927
2928 switch (lttng_session_descriptor_get_type(descriptor)) {
2929 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2930 new_session->snapshot_mode = 1;
2931 break;
2932 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
2933 new_session->live_timer =
2934 lttng_session_descriptor_live_get_timer_interval(
2935 descriptor);
2936 break;
2937 default:
2938 break;
2939 }
2940
2941 ret_code = set_session_output_from_descriptor(new_session, descriptor);
2942 if (ret_code != LTTNG_OK) {
2943 goto end;
2944 }
2945 new_session->consumer->enabled = 1;
2946 ret_code = LTTNG_OK;
2947 end:
2948 /* Release reference provided by the session_create function. */
2949 session_put(new_session);
2950 if (ret_code != LTTNG_OK && new_session) {
2951 /* Release the global reference on error. */
2952 session_destroy(new_session);
2953 }
2954 session_unlock_list();
2955 return ret_code;
2956 }
2957
2958 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
2959 struct lttng_session_descriptor **return_descriptor)
2960 {
2961 int ret;
2962 size_t payload_size;
2963 struct lttng_dynamic_buffer payload;
2964 struct lttng_buffer_view home_dir_view;
2965 struct lttng_buffer_view session_descriptor_view;
2966 struct lttng_session_descriptor *session_descriptor = NULL;
2967 enum lttng_error_code ret_code;
2968
2969 lttng_dynamic_buffer_init(&payload);
2970 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
2971 LTTNG_PATH_MAX) {
2972 ret_code = LTTNG_ERR_INVALID;
2973 goto error;
2974 }
2975 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
2976 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
2977 ret_code = LTTNG_ERR_INVALID;
2978 goto error;
2979 }
2980
2981 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
2982 cmd_ctx->lsm->u.create_session.session_descriptor_size;
2983 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
2984 if (ret) {
2985 ret_code = LTTNG_ERR_NOMEM;
2986 goto error;
2987 }
2988
2989 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
2990 if (ret <= 0) {
2991 ERR("Reception of session descriptor failed, aborting.");
2992 ret_code = LTTNG_ERR_SESSION_FAIL;
2993 goto error;
2994 }
2995
2996 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
2997 &payload,
2998 0,
2999 cmd_ctx->lsm->u.create_session.home_dir_size);
3000 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3001 &payload,
3002 cmd_ctx->lsm->u.create_session.home_dir_size,
3003 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3004
3005 ret = lttng_session_descriptor_create_from_buffer(
3006 &session_descriptor_view, &session_descriptor);
3007 if (ret < 0) {
3008 ERR("Failed to create session descriptor from payload of \"create session\" command");
3009 ret_code = LTTNG_ERR_INVALID;
3010 goto error;
3011 }
3012
3013 /*
3014 * Sets the descriptor's auto-generated properties (name, output) if
3015 * needed.
3016 */
3017 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3018 &cmd_ctx->creds,
3019 home_dir_view.size ? home_dir_view.data : NULL);
3020 if (ret_code != LTTNG_OK) {
3021 goto error;
3022 }
3023
3024 ret_code = LTTNG_OK;
3025 *return_descriptor = session_descriptor;
3026 session_descriptor = NULL;
3027 error:
3028 lttng_dynamic_buffer_reset(&payload);
3029 lttng_session_descriptor_destroy(session_descriptor);
3030 return ret_code;
3031 }
3032
3033 static
3034 void cmd_destroy_session_reply(const struct ltt_session *session,
3035 void *_reply_context)
3036 {
3037 int ret;
3038 ssize_t comm_ret;
3039 const struct cmd_destroy_session_reply_context *reply_context =
3040 _reply_context;
3041 struct lttng_dynamic_buffer payload;
3042 struct lttcomm_session_destroy_command_header cmd_header;
3043 struct lttng_trace_archive_location *location = NULL;
3044 struct lttcomm_lttng_msg llm = {
3045 .cmd_type = LTTNG_DESTROY_SESSION,
3046 .ret_code = LTTNG_OK,
3047 .pid = UINT32_MAX,
3048 .cmd_header_size =
3049 sizeof(struct lttcomm_session_destroy_command_header),
3050 .data_size = 0,
3051 };
3052 size_t payload_size_before_location;
3053
3054 lttng_dynamic_buffer_init(&payload);
3055
3056 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3057 if (ret) {
3058 ERR("Failed to append session destruction message");
3059 goto error;
3060 }
3061
3062 cmd_header.rotation_state =
3063 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3064 session->rotation_state :
3065 LTTNG_ROTATION_STATE_NO_ROTATION);
3066 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3067 sizeof(cmd_header));
3068 if (ret) {
3069 ERR("Failed to append session destruction command header");
3070 goto error;
3071 }
3072
3073 if (!reply_context->implicit_rotation_on_destroy) {
3074 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3075 session->name);
3076 goto send_reply;
3077 }
3078 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3079 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3080 session->name);
3081 goto send_reply;
3082 }
3083
3084 location = session_get_trace_archive_location(session);
3085 if (!location) {
3086 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3087 session->name);
3088 goto error;
3089 }
3090
3091 payload_size_before_location = payload.size;
3092 comm_ret = lttng_trace_archive_location_serialize(location,
3093 &payload);
3094 if (comm_ret < 0) {
3095 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3096 session->name);
3097 goto error;
3098 }
3099 /* Update the message to indicate the location's length. */
3100 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3101 payload.size - payload_size_before_location;
3102 send_reply:
3103 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3104 payload.data, payload.size);
3105 if (comm_ret != (ssize_t) payload.size) {
3106 ERR("Failed to send result of the destruction of session \"%s\" to client",
3107 session->name);
3108 }
3109 error:
3110 ret = close(reply_context->reply_sock_fd);
3111 if (ret) {
3112 PERROR("Failed to close client socket in deferred session destroy reply");
3113 }
3114 lttng_dynamic_buffer_reset(&payload);
3115 free(_reply_context);
3116 }
3117
3118 /*
3119 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3120 *
3121 * Called with session lock held.
3122 */
3123 int cmd_destroy_session(struct ltt_session *session,
3124 struct notification_thread_handle *notification_thread_handle,
3125 int *sock_fd)
3126 {
3127 int ret;
3128 struct cmd_destroy_session_reply_context *reply_context = NULL;
3129
3130 if (sock_fd) {
3131 reply_context = zmalloc(sizeof(*reply_context));
3132 if (!reply_context) {
3133 ret = LTTNG_ERR_NOMEM;
3134 goto end;
3135 }
3136 reply_context->reply_sock_fd = *sock_fd;
3137 }
3138
3139 /* Safety net */
3140 assert(session);
3141
3142 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3143 session->id);
3144 if (session->active) {
3145 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3146 session->name);
3147 ret = cmd_stop_trace(session);
3148 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3149 /* Carry on with the destruction of the session. */
3150 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3151 session->name, lttng_strerror(-ret));
3152 }
3153 }
3154
3155 if (session->rotation_schedule_timer_enabled) {
3156 if (timer_session_rotation_schedule_timer_stop(
3157 session)) {
3158 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3159 session->name);
3160 }
3161 }
3162
3163 if (session->rotate_size) {
3164 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3165 session->rotate_size = 0;
3166 }
3167
3168 if (session->most_recent_chunk_id.is_set &&
3169 session->most_recent_chunk_id.value != 0 &&
3170 session->current_trace_chunk) {
3171 ret = cmd_rotate_session(session, NULL);
3172 if (ret != LTTNG_OK) {
3173 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3174 session->name, lttng_strerror(-ret));
3175 }
3176 if (reply_context) {
3177 reply_context->implicit_rotation_on_destroy = true;
3178 }
3179 }
3180
3181 if (session->shm_path[0]) {
3182 /*
3183 * When a session is created with an explicit shm_path,
3184 * the consumer daemon will create its shared memory files
3185 * at that location and will *not* unlink them. This is normal
3186 * as the intention of that feature is to make it possible
3187 * to retrieve the content of those files should a crash occur.
3188 *
3189 * To ensure the content of those files can be used, the
3190 * sessiond daemon will replicate the content of the metadata
3191 * cache in a metadata file.
3192 *
3193 * On clean-up, it is expected that the consumer daemon will
3194 * unlink the shared memory files and that the session daemon
3195 * will unlink the metadata file. Then, the session's directory
3196 * in the shm path can be removed.
3197 *
3198 * Unfortunately, a flaw in the design of the sessiond's and
3199 * consumerd's tear down of channels makes it impossible to
3200 * determine when the sessiond _and_ the consumerd have both
3201 * destroyed their representation of a channel. For one, the
3202 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3203 * callbacks in both daemons.
3204 *
3205 * However, it is also impossible for the sessiond to know when
3206 * the consumer daemon is done destroying its channel(s) since
3207 * it occurs as a reaction to the closing of the channel's file
3208 * descriptor. There is no resulting communication initiated
3209 * from the consumerd to the sessiond to confirm that the
3210 * operation is completed (and was successful).
3211 *
3212 * Until this is all fixed, the session daemon checks for the
3213 * removal of the session's shm path which makes it possible
3214 * to safely advertise a session as having been destroyed.
3215 *
3216 * Prior to this fix, it was not possible to reliably save
3217 * a session making use of the --shm-path option, destroy it,
3218 * and load it again. This is because the creation of the
3219 * session would fail upon seeing the session's shm path
3220 * already in existence.
3221 *
3222 * Note that none of the error paths in the check for the
3223 * directory's existence return an error. This is normal
3224 * as there isn't much that can be done. The session will
3225 * be destroyed properly, except that we can't offer the
3226 * guarantee that the same session can be re-created.
3227 */
3228 current_completion_handler = &destroy_completion_handler.handler;
3229 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3230 session->shm_path,
3231 sizeof(destroy_completion_handler.shm_path));
3232 assert(!ret);
3233 }
3234
3235 /*
3236 * The session is destroyed. However, note that the command context
3237 * still holds a reference to the session, thus delaying its destruction
3238 * _at least_ up to the point when that reference is released.
3239 */
3240 session_destroy(session);
3241 if (reply_context) {
3242 ret = session_add_destroy_notifier(session,
3243 cmd_destroy_session_reply,
3244 (void *) reply_context);
3245 if (ret) {
3246 ret = LTTNG_ERR_FATAL;
3247 goto end;
3248 } else {
3249 *sock_fd = -1;
3250 }
3251 }
3252 ret = LTTNG_OK;
3253 end:
3254 return ret;
3255 }
3256
3257 /*
3258 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3259 */
3260 int cmd_register_consumer(struct ltt_session *session,
3261 enum lttng_domain_type domain, const char *sock_path,
3262 struct consumer_data *cdata)
3263 {
3264 int ret, sock;
3265 struct consumer_socket *socket = NULL;
3266
3267 assert(session);
3268 assert(cdata);
3269 assert(sock_path);
3270
3271 switch (domain) {
3272 case LTTNG_DOMAIN_KERNEL:
3273 {
3274 struct ltt_kernel_session *ksess = session->kernel_session;
3275
3276 assert(ksess);
3277
3278 /* Can't register a consumer if there is already one */
3279 if (ksess->consumer_fds_sent != 0) {
3280 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3281 goto error;
3282 }
3283
3284 sock = lttcomm_connect_unix_sock(sock_path);
3285 if (sock < 0) {
3286 ret = LTTNG_ERR_CONNECT_FAIL;
3287 goto error;
3288 }
3289 cdata->cmd_sock = sock;
3290
3291 socket = consumer_allocate_socket(&cdata->cmd_sock);
3292 if (socket == NULL) {
3293 ret = close(sock);
3294 if (ret < 0) {
3295 PERROR("close register consumer");
3296 }
3297 cdata->cmd_sock = -1;
3298 ret = LTTNG_ERR_FATAL;
3299 goto error;
3300 }
3301
3302 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3303 if (socket->lock == NULL) {
3304 PERROR("zmalloc pthread mutex");
3305 ret = LTTNG_ERR_FATAL;
3306 goto error;
3307 }
3308 pthread_mutex_init(socket->lock, NULL);
3309 socket->registered = 1;
3310
3311 rcu_read_lock();
3312 consumer_add_socket(socket, ksess->consumer);
3313 rcu_read_unlock();
3314
3315 pthread_mutex_lock(&cdata->pid_mutex);
3316 cdata->pid = -1;
3317 pthread_mutex_unlock(&cdata->pid_mutex);
3318
3319 break;
3320 }
3321 default:
3322 /* TODO: Userspace tracing */
3323 ret = LTTNG_ERR_UND;
3324 goto error;
3325 }
3326
3327 return LTTNG_OK;
3328
3329 error:
3330 if (socket) {
3331 consumer_destroy_socket(socket);
3332 }
3333 return ret;
3334 }
3335
3336 /*
3337 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3338 */
3339 ssize_t cmd_list_domains(struct ltt_session *session,
3340 struct lttng_domain **domains)
3341 {
3342 int ret, index = 0;
3343 ssize_t nb_dom = 0;
3344 struct agent *agt;
3345 struct lttng_ht_iter iter;
3346
3347 if (session->kernel_session != NULL) {
3348 DBG3("Listing domains found kernel domain");
3349 nb_dom++;
3350 }
3351
3352 if (session->ust_session != NULL) {
3353 DBG3("Listing domains found UST global domain");
3354 nb_dom++;
3355
3356 rcu_read_lock();
3357 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3358 agt, node.node) {
3359 if (agt->being_used) {
3360 nb_dom++;
3361 }
3362 }
3363 rcu_read_unlock();
3364 }
3365
3366 if (!nb_dom) {
3367 goto end;
3368 }
3369
3370 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3371 if (*domains == NULL) {
3372 ret = LTTNG_ERR_FATAL;
3373 goto error;
3374 }
3375
3376 if (session->kernel_session != NULL) {
3377 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3378
3379 /* Kernel session buffer type is always GLOBAL */
3380 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3381
3382 index++;
3383 }
3384
3385 if (session->ust_session != NULL) {
3386 (*domains)[index].type = LTTNG_DOMAIN_UST;
3387 (*domains)[index].buf_type = session->ust_session->buffer_type;
3388 index++;
3389
3390 rcu_read_lock();
3391 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3392 agt, node.node) {
3393 if (agt->being_used) {
3394 (*domains)[index].type = agt->domain;
3395 (*domains)[index].buf_type = session->ust_session->buffer_type;
3396 index++;
3397 }
3398 }
3399 rcu_read_unlock();
3400 }
3401 end:
3402 return nb_dom;
3403
3404 error:
3405 /* Return negative value to differentiate return code */
3406 return -ret;
3407 }
3408
3409
3410 /*
3411 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3412 */
3413 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3414 struct ltt_session *session, struct lttng_channel **channels)
3415 {
3416 ssize_t nb_chan = 0, payload_size = 0, ret;
3417
3418 switch (domain) {
3419 case LTTNG_DOMAIN_KERNEL:
3420 if (session->kernel_session != NULL) {
3421 nb_chan = session->kernel_session->channel_count;
3422 }
3423 DBG3("Number of kernel channels %zd", nb_chan);
3424 if (nb_chan <= 0) {
3425 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3426 goto end;
3427 }
3428 break;
3429 case LTTNG_DOMAIN_UST:
3430 if (session->ust_session != NULL) {
3431 rcu_read_lock();
3432 nb_chan = lttng_ht_get_count(
3433 session->ust_session->domain_global.channels);
3434 rcu_read_unlock();
3435 }
3436 DBG3("Number of UST global channels %zd", nb_chan);
3437 if (nb_chan < 0) {
3438 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3439 goto end;
3440 }
3441 break;
3442 default:
3443 ret = -LTTNG_ERR_UND;
3444 goto end;
3445 }
3446
3447 if (nb_chan > 0) {
3448 const size_t channel_size = sizeof(struct lttng_channel) +
3449 sizeof(struct lttng_channel_extended);
3450 struct lttng_channel_extended *channel_exts;
3451
3452 payload_size = nb_chan * channel_size;
3453 *channels = zmalloc(payload_size);
3454 if (*channels == NULL) {
3455 ret = -LTTNG_ERR_FATAL;
3456 goto end;
3457 }
3458
3459 channel_exts = ((void *) *channels) +
3460 (nb_chan * sizeof(struct lttng_channel));
3461 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3462 if (ret != LTTNG_OK) {
3463 free(*channels);
3464 *channels = NULL;
3465 goto end;
3466 }
3467 } else {
3468 *channels = NULL;
3469 }
3470
3471 ret = payload_size;
3472 end:
3473 return ret;
3474 }
3475
3476 /*
3477 * Command LTTNG_LIST_EVENTS processed by the client thread.
3478 */
3479 ssize_t cmd_list_events(enum lttng_domain_type domain,
3480 struct ltt_session *session, char *channel_name,
3481 struct lttng_event **events, size_t *total_size)
3482 {
3483 int ret = 0;
3484 ssize_t nb_event = 0;
3485
3486 switch (domain) {
3487 case LTTNG_DOMAIN_KERNEL:
3488 if (session->kernel_session != NULL) {
3489 nb_event = list_lttng_kernel_events(channel_name,
3490 session->kernel_session, events,
3491 total_size);
3492 }
3493 break;
3494 case LTTNG_DOMAIN_UST:
3495 {
3496 if (session->ust_session != NULL) {
3497 nb_event = list_lttng_ust_global_events(channel_name,
3498 &session->ust_session->domain_global, events,
3499 total_size);
3500 }
3501 break;
3502 }
3503 case LTTNG_DOMAIN_LOG4J:
3504 case LTTNG_DOMAIN_JUL:
3505 case LTTNG_DOMAIN_PYTHON:
3506 if (session->ust_session) {
3507 struct lttng_ht_iter iter;
3508 struct agent *agt;
3509
3510 rcu_read_lock();
3511 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3512 &iter.iter, agt, node.node) {
3513 if (agt->domain == domain) {
3514 nb_event = list_lttng_agent_events(
3515 agt, events,
3516 total_size);
3517 break;
3518 }
3519 }
3520 rcu_read_unlock();
3521 }
3522 break;
3523 default:
3524 ret = LTTNG_ERR_UND;
3525 goto error;
3526 }
3527
3528 return nb_event;
3529
3530 error:
3531 /* Return negative value to differentiate return code */
3532 return -ret;
3533 }
3534
3535 /*
3536 * Using the session list, filled a lttng_session array to send back to the
3537 * client for session listing.
3538 *
3539 * The session list lock MUST be acquired before calling this function. Use
3540 * session_lock_list() and session_unlock_list().
3541 */
3542 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3543 size_t session_count, uid_t uid, gid_t gid)
3544 {
3545 int ret;
3546 unsigned int i = 0;
3547 struct ltt_session *session;
3548 struct ltt_session_list *list = session_get_list();
3549 struct lttng_session_extended *extended =
3550 (typeof(extended)) (&sessions[session_count]);
3551
3552 DBG("Getting all available session for UID %d GID %d",
3553 uid, gid);
3554 /*
3555 * Iterate over session list and append data after the control struct in
3556 * the buffer.
3557 */
3558 cds_list_for_each_entry(session, &list->head, list) {
3559 if (!session_get(session)) {
3560 continue;
3561 }
3562 /*
3563 * Only list the sessions the user can control.
3564 */
3565 if (!session_access_ok(session, uid, gid) ||
3566 session->destroyed) {
3567 session_put(session);
3568 continue;
3569 }
3570
3571 struct ltt_kernel_session *ksess = session->kernel_session;
3572 struct ltt_ust_session *usess = session->ust_session;
3573
3574 if (session->consumer->type == CONSUMER_DST_NET ||
3575 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3576 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3577 ret = build_network_session_path(sessions[i].path,
3578 sizeof(sessions[i].path), session);
3579 } else {
3580 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3581 session->consumer->dst.session_root_path);
3582 }
3583 if (ret < 0) {
3584 PERROR("snprintf session path");
3585 session_put(session);
3586 continue;
3587 }
3588
3589 strncpy(sessions[i].name, session->name, NAME_MAX);
3590 sessions[i].name[NAME_MAX - 1] = '\0';
3591 sessions[i].enabled = session->active;
3592 sessions[i].snapshot_mode = session->snapshot_mode;
3593 sessions[i].live_timer_interval = session->live_timer;
3594 extended[i].creation_time.value = (uint64_t) session->creation_time;
3595 extended[i].creation_time.is_set = 1;
3596 i++;
3597 session_put(session);
3598 }
3599 }
3600
3601 /*
3602 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3603 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3604 */
3605 int cmd_data_pending(struct ltt_session *session)
3606 {
3607 int ret;
3608 struct ltt_kernel_session *ksess = session->kernel_session;
3609 struct ltt_ust_session *usess = session->ust_session;
3610
3611 assert(session);
3612
3613 DBG("Data pending for session %s", session->name);
3614
3615 /* Session MUST be stopped to ask for data availability. */
3616 if (session->active) {
3617 ret = LTTNG_ERR_SESSION_STARTED;
3618 goto error;
3619 } else {
3620 /*
3621 * If stopped, just make sure we've started before else the above call
3622 * will always send that there is data pending.
3623 *
3624 * The consumer assumes that when the data pending command is received,
3625 * the trace has been started before or else no output data is written
3626 * by the streams which is a condition for data pending. So, this is
3627 * *VERY* important that we don't ask the consumer before a start
3628 * trace.
3629 */
3630 if (!session->has_been_started) {
3631 ret = 0;
3632 goto error;
3633 }
3634 }
3635
3636 /* A rotation is still pending, we have to wait. */
3637 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3638 DBG("Rotate still pending for session %s", session->name);
3639 ret = 1;
3640 goto error;
3641 }
3642
3643 if (ksess && ksess->consumer) {
3644 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3645 if (ret == 1) {
3646 /* Data is still being extracted for the kernel. */
3647 goto error;
3648 }
3649 }
3650
3651 if (usess && usess->consumer) {
3652 ret = consumer_is_data_pending(usess->id, usess->consumer);
3653 if (ret == 1) {
3654 /* Data is still being extracted for the kernel. */
3655 goto error;
3656 }
3657 }
3658
3659 /* Data is ready to be read by a viewer */
3660 ret = 0;
3661
3662 error:
3663 return ret;
3664 }
3665
3666 /*
3667 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3668 *
3669 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3670 */
3671 int cmd_snapshot_add_output(struct ltt_session *session,
3672 struct lttng_snapshot_output *output, uint32_t *id)
3673 {
3674 int ret;
3675 struct snapshot_output *new_output;
3676
3677 assert(session);
3678 assert(output);
3679
3680 DBG("Cmd snapshot add output for session %s", session->name);
3681
3682 /*
3683 * Can't create an output if the session is not set in no-output mode.
3684 */
3685 if (session->output_traces) {
3686 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3687 goto error;
3688 }
3689
3690 if (session->has_non_mmap_channel) {
3691 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3692 goto error;
3693 }
3694
3695 /* Only one output is allowed until we have the "tee" feature. */
3696 if (session->snapshot.nb_output == 1) {
3697 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3698 goto error;
3699 }
3700
3701 new_output = snapshot_output_alloc();
3702 if (!new_output) {
3703 ret = LTTNG_ERR_NOMEM;
3704 goto error;
3705 }
3706
3707 ret = snapshot_output_init(session, output->max_size, output->name,
3708 output->ctrl_url, output->data_url, session->consumer, new_output,
3709 &session->snapshot);
3710 if (ret < 0) {
3711 if (ret == -ENOMEM) {
3712 ret = LTTNG_ERR_NOMEM;
3713 } else {
3714 ret = LTTNG_ERR_INVALID;
3715 }
3716 goto free_error;
3717 }
3718
3719 rcu_read_lock();
3720 snapshot_add_output(&session->snapshot, new_output);
3721 if (id) {
3722 *id = new_output->id;
3723 }
3724 rcu_read_unlock();
3725
3726 return LTTNG_OK;
3727
3728 free_error:
3729 snapshot_output_destroy(new_output);
3730 error:
3731 return ret;
3732 }
3733
3734 /*
3735 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3736 *
3737 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3738 */
3739 int cmd_snapshot_del_output(struct ltt_session *session,
3740 struct lttng_snapshot_output *output)
3741 {
3742 int ret;
3743 struct snapshot_output *sout = NULL;
3744
3745 assert(session);
3746 assert(output);
3747
3748 rcu_read_lock();
3749
3750 /*
3751 * Permission denied to create an output if the session is not
3752 * set in no output mode.
3753 */
3754 if (session->output_traces) {
3755 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3756 goto error;
3757 }
3758
3759 if (output->id) {
3760 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3761 session->name);
3762 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3763 } else if (*output->name != '\0') {
3764 DBG("Cmd snapshot del output name %s for session %s", output->name,
3765 session->name);
3766 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3767 }
3768 if (!sout) {
3769 ret = LTTNG_ERR_INVALID;
3770 goto error;
3771 }
3772
3773 snapshot_delete_output(&session->snapshot, sout);
3774 snapshot_output_destroy(sout);
3775 ret = LTTNG_OK;
3776
3777 error:
3778 rcu_read_unlock();
3779 return ret;
3780 }
3781
3782 /*
3783 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3784 *
3785 * If no output is available, outputs is untouched and 0 is returned.
3786 *
3787 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3788 */
3789 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3790 struct lttng_snapshot_output **outputs)
3791 {
3792 int ret, idx = 0;
3793 struct lttng_snapshot_output *list = NULL;
3794 struct lttng_ht_iter iter;
3795 struct snapshot_output *output;
3796
3797 assert(session);
3798 assert(outputs);
3799
3800 DBG("Cmd snapshot list outputs for session %s", session->name);
3801
3802 /*
3803 * Permission denied to create an output if the session is not
3804 * set in no output mode.
3805 */
3806 if (session->output_traces) {
3807 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3808 goto end;
3809 }
3810
3811 if (session->snapshot.nb_output == 0) {
3812 ret = 0;
3813 goto end;
3814 }
3815
3816 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3817 if (!list) {
3818 ret = -LTTNG_ERR_NOMEM;
3819 goto end;
3820 }
3821
3822 /* Copy list from session to the new list object. */
3823 rcu_read_lock();
3824 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
3825 output, node.node) {
3826 assert(output->consumer);
3827 list[idx].id = output->id;
3828 list[idx].max_size = output->max_size;
3829 if (lttng_strncpy(list[idx].name, output->name,
3830 sizeof(list[idx].name))) {
3831 ret = -LTTNG_ERR_INVALID;
3832 goto error;
3833 }
3834 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3835 if (lttng_strncpy(list[idx].ctrl_url,
3836 output->consumer->dst.session_root_path,
3837 sizeof(list[idx].ctrl_url))) {
3838 ret = -LTTNG_ERR_INVALID;
3839 goto error;
3840 }
3841 } else {
3842 /* Control URI. */
3843 ret = uri_to_str_url(&output->consumer->dst.net.control,
3844 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3845 if (ret < 0) {
3846 ret = -LTTNG_ERR_NOMEM;
3847 goto error;
3848 }
3849
3850 /* Data URI. */
3851 ret = uri_to_str_url(&output->consumer->dst.net.data,
3852 list[idx].data_url, sizeof(list[idx].data_url));
3853 if (ret < 0) {
3854 ret = -LTTNG_ERR_NOMEM;
3855 goto error;
3856 }
3857 }
3858 idx++;
3859 }
3860
3861 *outputs = list;
3862 list = NULL;
3863 ret = session->snapshot.nb_output;
3864 error:
3865 rcu_read_unlock();
3866 free(list);
3867 end:
3868 return ret;
3869 }
3870
3871 /*
3872 * Check if we can regenerate the metadata for this session.
3873 * Only kernel, UST per-uid and non-live sessions are supported.
3874 *
3875 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
3876 */
3877 static
3878 int check_regenerate_metadata_support(struct ltt_session *session)
3879 {
3880 int ret;
3881
3882 assert(session);
3883
3884 if (session->live_timer != 0) {
3885 ret = LTTNG_ERR_LIVE_SESSION;
3886 goto end;
3887 }
3888 if (!session->active) {
3889 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3890 goto end;
3891 }
3892 if (session->ust_session) {
3893 switch (session->ust_session->buffer_type) {
3894 case LTTNG_BUFFER_PER_UID:
3895 break;
3896 case LTTNG_BUFFER_PER_PID:
3897 ret = LTTNG_ERR_PER_PID_SESSION;
3898 goto end;
3899 default:
3900 assert(0);
3901 ret = LTTNG_ERR_UNK;
3902 goto end;
3903 }
3904 }
3905 if (session->consumer->type == CONSUMER_DST_NET &&
3906 session->consumer->relay_minor_version < 8) {
3907 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
3908 goto end;
3909 }
3910 ret = 0;
3911
3912 end:
3913 return ret;
3914 }
3915
3916 static
3917 int clear_metadata_file(int fd)
3918 {
3919 int ret;
3920 off_t lseek_ret;
3921
3922 lseek_ret = lseek(fd, 0, SEEK_SET);
3923 if (lseek_ret < 0) {
3924 PERROR("lseek");
3925 ret = -1;
3926 goto end;
3927 }
3928
3929 ret = ftruncate(fd, 0);
3930 if (ret < 0) {
3931 PERROR("ftruncate");
3932 goto end;
3933 }
3934
3935 end:
3936 return ret;
3937 }
3938
3939 static
3940 int ust_regenerate_metadata(struct ltt_ust_session *usess)
3941 {
3942 int ret = 0;
3943 struct buffer_reg_uid *uid_reg = NULL;
3944 struct buffer_reg_session *session_reg = NULL;
3945
3946 rcu_read_lock();
3947 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
3948 struct ust_registry_session *registry;
3949 struct ust_registry_channel *chan;
3950 struct lttng_ht_iter iter_chan;
3951
3952 session_reg = uid_reg->registry;
3953 registry = session_reg->reg.ust;
3954
3955 pthread_mutex_lock(&registry->lock);
3956 registry->metadata_len_sent = 0;
3957 memset(registry->metadata, 0, registry->metadata_alloc_len);
3958 registry->metadata_len = 0;
3959 registry->metadata_version++;
3960 if (registry->metadata_fd > 0) {
3961 /* Clear the metadata file's content. */
3962 ret = clear_metadata_file(registry->metadata_fd);
3963 if (ret) {
3964 pthread_mutex_unlock(&registry->lock);
3965 goto end;
3966 }
3967 }
3968
3969 ret = ust_metadata_session_statedump(registry, NULL,
3970 registry->major, registry->minor);
3971 if (ret) {
3972 pthread_mutex_unlock(&registry->lock);
3973 ERR("Failed to generate session metadata (err = %d)",
3974 ret);
3975 goto end;
3976 }
3977 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
3978 chan, node.node) {
3979 struct ust_registry_event *event;
3980 struct lttng_ht_iter iter_event;
3981
3982 ret = ust_metadata_channel_statedump(registry, chan);
3983 if (ret) {
3984 pthread_mutex_unlock(&registry->lock);
3985 ERR("Failed to generate channel metadata "
3986 "(err = %d)", ret);
3987 goto end;
3988 }
3989 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
3990 event, node.node) {
3991 ret = ust_metadata_event_statedump(registry,
3992 chan, event);
3993 if (ret) {
3994 pthread_mutex_unlock(&registry->lock);
3995 ERR("Failed to generate event metadata "
3996 "(err = %d)", ret);
3997 goto end;
3998 }
3999 }
4000 }
4001 pthread_mutex_unlock(&registry->lock);
4002 }
4003
4004 end:
4005 rcu_read_unlock();
4006 return ret;
4007 }
4008
4009 /*
4010 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4011 *
4012 * Ask the consumer to truncate the existing metadata file(s) and
4013 * then regenerate the metadata. Live and per-pid sessions are not
4014 * supported and return an error.
4015 *
4016 * Return 0 on success or else a LTTNG_ERR code.
4017 */
4018 int cmd_regenerate_metadata(struct ltt_session *session)
4019 {
4020 int ret;
4021
4022 assert(session);
4023
4024 ret = check_regenerate_metadata_support(session);
4025 if (ret) {
4026 goto end;
4027 }
4028
4029 if (session->kernel_session) {
4030 ret = kernctl_session_regenerate_metadata(
4031 session->kernel_session->fd);
4032 if (ret < 0) {
4033 ERR("Failed to regenerate the kernel metadata");
4034 goto end;
4035 }
4036 }
4037
4038 if (session->ust_session) {
4039 ret = ust_regenerate_metadata(session->ust_session);
4040 if (ret < 0) {
4041 ERR("Failed to regenerate the UST metadata");
4042 goto end;
4043 }
4044 }
4045 DBG("Cmd metadata regenerate for session %s", session->name);
4046 ret = LTTNG_OK;
4047
4048 end:
4049 return ret;
4050 }
4051
4052 /*
4053 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4054 *
4055 * Ask the tracer to regenerate a new statedump.
4056 *
4057 * Return 0 on success or else a LTTNG_ERR code.
4058 */
4059 int cmd_regenerate_statedump(struct ltt_session *session)
4060 {
4061 int ret;
4062
4063 assert(session);
4064
4065 if (!session->active) {
4066 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4067 goto end;
4068 }
4069
4070 if (session->kernel_session) {
4071 ret = kernctl_session_regenerate_statedump(
4072 session->kernel_session->fd);
4073 /*
4074 * Currently, the statedump in kernel can only fail if out
4075 * of memory.
4076 */
4077 if (ret < 0) {
4078 if (ret == -ENOMEM) {
4079 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4080 } else {
4081 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4082 }
4083 ERR("Failed to regenerate the kernel statedump");
4084 goto end;
4085 }
4086 }
4087
4088 if (session->ust_session) {
4089 ret = ust_app_regenerate_statedump_all(session->ust_session);
4090 /*
4091 * Currently, the statedump in UST always returns 0.
4092 */
4093 if (ret < 0) {
4094 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4095 ERR("Failed to regenerate the UST statedump");
4096 goto end;
4097 }
4098 }
4099 DBG("Cmd regenerate statedump for session %s", session->name);
4100 ret = LTTNG_OK;
4101
4102 end:
4103 return ret;
4104 }
4105
4106 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4107 struct notification_thread_handle *notification_thread)
4108 {
4109 int ret;
4110 size_t trigger_len;
4111 ssize_t sock_recv_len;
4112 struct lttng_trigger *trigger = NULL;
4113 struct lttng_buffer_view view;
4114 struct lttng_dynamic_buffer trigger_buffer;
4115
4116 lttng_dynamic_buffer_init(&trigger_buffer);
4117 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4118 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4119 if (ret) {
4120 ret = LTTNG_ERR_NOMEM;
4121 goto end;
4122 }
4123
4124 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4125 trigger_len);
4126 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4127 ERR("Failed to receive \"register trigger\" command payload");
4128 /* TODO: should this be a new error enum ? */
4129 ret = LTTNG_ERR_INVALID_TRIGGER;
4130 goto end;
4131 }
4132
4133 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4134 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4135 trigger_len) {
4136 ERR("Invalid trigger payload received in \"register trigger\" command");
4137 ret = LTTNG_ERR_INVALID_TRIGGER;
4138 goto end;
4139 }
4140
4141 ret = notification_thread_command_register_trigger(notification_thread,
4142 trigger);
4143 /* Ownership of trigger was transferred. */
4144 trigger = NULL;
4145 end:
4146 lttng_trigger_destroy(trigger);
4147 lttng_dynamic_buffer_reset(&trigger_buffer);
4148 return ret;
4149 }
4150
4151 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4152 struct notification_thread_handle *notification_thread)
4153 {
4154 int ret;
4155 size_t trigger_len;
4156 ssize_t sock_recv_len;
4157 struct lttng_trigger *trigger = NULL;
4158 struct lttng_buffer_view view;
4159 struct lttng_dynamic_buffer trigger_buffer;
4160
4161 lttng_dynamic_buffer_init(&trigger_buffer);
4162 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4163 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4164 if (ret) {
4165 ret = LTTNG_ERR_NOMEM;
4166 goto end;
4167 }
4168
4169 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4170 trigger_len);
4171 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4172 ERR("Failed to receive \"unregister trigger\" command payload");
4173 /* TODO: should this be a new error enum ? */
4174 ret = LTTNG_ERR_INVALID_TRIGGER;
4175 goto end;
4176 }
4177
4178 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4179 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4180 trigger_len) {
4181 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4182 ret = LTTNG_ERR_INVALID_TRIGGER;
4183 goto end;
4184 }
4185
4186 ret = notification_thread_command_unregister_trigger(notification_thread,
4187 trigger);
4188 end:
4189 lttng_trigger_destroy(trigger);
4190 lttng_dynamic_buffer_reset(&trigger_buffer);
4191 return ret;
4192 }
4193
4194 /*
4195 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4196 * snapshot output is *not* set with a remote destination.
4197 *
4198 * Return LTTNG_OK on success or a LTTNG_ERR code.
4199 */
4200 static enum lttng_error_code set_relayd_for_snapshot(
4201 struct consumer_output *consumer,
4202 const struct snapshot_output *snap_output,
4203 const struct ltt_session *session)
4204 {
4205 enum lttng_error_code status = LTTNG_OK;
4206 struct lttng_ht_iter iter;
4207 struct consumer_socket *socket;
4208 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4209
4210 assert(consumer);
4211 assert(snap_output);
4212 assert(session);
4213
4214 DBG2("Set relayd object from snapshot output");
4215
4216 if (session->current_trace_chunk) {
4217 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
4218 session->current_trace_chunk, &current_chunk_id.value);
4219
4220 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4221 current_chunk_id.is_set = true;
4222 } else {
4223 ERR("Failed to get current trace chunk id");
4224 status = LTTNG_ERR_UNK;
4225 goto error;
4226 }
4227 }
4228
4229 /* Ignore if snapshot consumer output is not network. */
4230 if (snap_output->consumer->type != CONSUMER_DST_NET) {
4231 goto error;
4232 }
4233
4234 /*
4235 * For each consumer socket, create and send the relayd object of the
4236 * snapshot output.
4237 */
4238 rcu_read_lock();
4239 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
4240 socket, node.node) {
4241 pthread_mutex_lock(socket->lock);
4242 status = send_consumer_relayd_sockets(0, session->id,
4243 snap_output->consumer, socket,
4244 session->name, session->hostname,
4245 session->live_timer,
4246 current_chunk_id.is_set ? &current_chunk_id.value : NULL);
4247 pthread_mutex_unlock(socket->lock);
4248 if (status != LTTNG_OK) {
4249 rcu_read_unlock();
4250 goto error;
4251 }
4252 }
4253 rcu_read_unlock();
4254
4255 error:
4256 return status;
4257 }
4258
4259 /*
4260 * Record a kernel snapshot.
4261 *
4262 * Return LTTNG_OK on success or a LTTNG_ERR code.
4263 */
4264 static enum lttng_error_code record_kernel_snapshot(
4265 struct ltt_kernel_session *ksess,
4266 const struct snapshot_output *output,
4267 const struct ltt_session *session,
4268 int wait, uint64_t nb_packets_per_stream)
4269 {
4270 int ret;
4271 enum lttng_error_code status;
4272
4273 assert(ksess);
4274 assert(output);
4275 assert(session);
4276
4277 /*
4278 * Copy kernel session sockets so we can communicate with the right
4279 * consumer for the snapshot record command.
4280 */
4281 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
4282 if (ret < 0) {
4283 status = LTTNG_ERR_NOMEM;
4284 goto error;
4285 }
4286
4287 status = set_relayd_for_snapshot(ksess->consumer, output, session);
4288 if (status != LTTNG_OK) {
4289 goto error_snapshot;
4290 }
4291
4292 status = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
4293 if (status != LTTNG_OK) {
4294 goto error_snapshot;
4295 }
4296
4297 goto end;
4298
4299 error_snapshot:
4300 /* Clean up copied sockets so this output can use some other later on. */
4301 consumer_destroy_output_sockets(output->consumer);
4302 error:
4303 end:
4304 return status;
4305 }
4306
4307 /*
4308 * Record a UST snapshot.
4309 *
4310 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4311 */
4312 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4313 const struct snapshot_output *output,
4314 const struct ltt_session *session, int wait,
4315 uint64_t nb_packets_per_stream)
4316 {
4317 int ret;
4318 enum lttng_error_code status;
4319
4320 assert(usess);
4321 assert(output);
4322 assert(session);
4323
4324 /*
4325 * Copy UST session sockets so we can communicate with the right
4326 * consumer for the snapshot record command.
4327 */
4328 ret = consumer_copy_sockets(output->consumer, usess->consumer);
4329 if (ret < 0) {
4330 status = LTTNG_ERR_NOMEM;
4331 goto error;
4332 }
4333
4334 status = set_relayd_for_snapshot(usess->consumer, output, session);
4335 if (status != LTTNG_OK) {
4336 goto error_snapshot;
4337 }
4338
4339 status = ust_app_snapshot_record(usess, output, wait,
4340 nb_packets_per_stream);
4341 if (status != LTTNG_OK) {
4342 goto error_snapshot;
4343 }
4344
4345 goto end;
4346
4347 error_snapshot:
4348 /* Clean up copied sockets so this output can use some other later on. */
4349 consumer_destroy_output_sockets(output->consumer);
4350 error:
4351 end:
4352 return status;
4353 }
4354
4355 static
4356 uint64_t get_session_size_one_more_packet_per_stream(
4357 const struct ltt_session *session, uint64_t cur_nr_packets)
4358 {
4359 uint64_t tot_size = 0;
4360
4361 if (session->kernel_session) {
4362 struct ltt_kernel_channel *chan;
4363 const struct ltt_kernel_session *ksess =
4364 session->kernel_session;
4365
4366 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4367 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4368 /*
4369 * Don't take channel into account if we
4370 * already grab all its packets.
4371 */
4372 continue;
4373 }
4374 tot_size += chan->channel->attr.subbuf_size
4375 * chan->stream_count;
4376 }
4377 }
4378
4379 if (session->ust_session) {
4380 const struct ltt_ust_session *usess = session->ust_session;
4381
4382 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4383 cur_nr_packets);
4384 }
4385
4386 return tot_size;
4387 }
4388
4389 /*
4390 * Calculate the number of packets we can grab from each stream that
4391 * fits within the overall snapshot max size.
4392 *
4393 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4394 * the number of packets per stream.
4395 *
4396 * TODO: this approach is not perfect: we consider the worse case
4397 * (packet filling the sub-buffers) as an upper bound, but we could do
4398 * better if we do this calculation while we actually grab the packet
4399 * content: we would know how much padding we don't actually store into
4400 * the file.
4401 *
4402 * This algorithm is currently bounded by the number of packets per
4403 * stream.
4404 *
4405 * Since we call this algorithm before actually grabbing the data, it's
4406 * an approximation: for instance, applications could appear/disappear
4407 * in between this call and actually grabbing data.
4408 */
4409 static
4410 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4411 uint64_t max_size)
4412 {
4413 int64_t size_left;
4414 uint64_t cur_nb_packets = 0;
4415
4416 if (!max_size) {
4417 return 0; /* Infinite */
4418 }
4419
4420 size_left = max_size;
4421 for (;;) {
4422 uint64_t one_more_packet_tot_size;
4423
4424 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4425 session, cur_nb_packets);
4426 if (!one_more_packet_tot_size) {
4427 /* We are already grabbing all packets. */
4428 break;
4429 }
4430 size_left -= one_more_packet_tot_size;
4431 if (size_left < 0) {
4432 break;
4433 }
4434 cur_nb_packets++;
4435 }
4436 if (!cur_nb_packets) {
4437 /* Not enough room to grab one packet of each stream, error. */
4438 return -1;
4439 }
4440 return cur_nb_packets;
4441 }
4442
4443 static
4444 enum lttng_error_code snapshot_record(struct ltt_session *session,
4445 const struct snapshot_output *snapshot_output, int wait)
4446 {
4447 int fmt_ret;
4448 int64_t nb_packets_per_stream;
4449 char snapshot_chunk_name[LTTNG_NAME_MAX];
4450 enum lttng_error_code ret = LTTNG_OK;
4451 struct lttng_trace_chunk *snapshot_trace_chunk;
4452
4453 fmt_ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4454 "%s-%s-%" PRIu64,
4455 snapshot_output->name,
4456 snapshot_output->datetime,
4457 snapshot_output->nb_snapshot);
4458 if (fmt_ret < 0 || fmt_ret >= sizeof(snapshot_chunk_name)) {
4459 ERR("Failed to format snapshot name");
4460 ret = LTTNG_ERR_INVALID;
4461 goto end;
4462 }
4463 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4464 snapshot_output->name, session->name,
4465 snapshot_chunk_name);
4466 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4467 snapshot_output_get_base_path(snapshot_output),
4468 snapshot_chunk_name);
4469 if (!snapshot_trace_chunk) {
4470 ret = LTTNG_ERR_CREATE_DIR_FAIL;
4471 goto end;
4472 }
4473 assert(!session->current_trace_chunk);
4474 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4475 lttng_trace_chunk_put(snapshot_trace_chunk);
4476 snapshot_trace_chunk = NULL;
4477 if (ret) {
4478 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4479 goto end;
4480 }
4481
4482 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4483 snapshot_output->max_size);
4484 if (nb_packets_per_stream < 0) {
4485 ret = LTTNG_ERR_MAX_SIZE_INVALID;
4486 goto end;
4487 }
4488
4489 if (session->kernel_session) {
4490 ret = record_kernel_snapshot(session->kernel_session,
4491 snapshot_output, session,
4492 wait, nb_packets_per_stream);
4493 if (ret != LTTNG_OK) {
4494 goto end;
4495 }
4496 }
4497
4498 if (session->ust_session) {
4499 ret = record_ust_snapshot(session->ust_session,
4500 snapshot_output, session,
4501 wait, nb_packets_per_stream);
4502 if (ret != LTTNG_OK) {
4503 goto end;
4504 }
4505 }
4506
4507 if (session_close_trace_chunk(session, session->current_trace_chunk)) {
4508 /*
4509 * Don't goto end; make sure the chunk is closed for the session
4510 * to allow future snapshots.
4511 */
4512 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4513 session->name);
4514 ret = -1;
4515 }
4516 if (session_set_trace_chunk(session, NULL, NULL)) {
4517 ERR("Failed to release the current trace chunk of session \"%s\"",
4518 session->name);
4519 ret = -1;
4520 }
4521 end:
4522 return ret;
4523 }
4524
4525 /*
4526 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4527 *
4528 * The wait parameter is ignored so this call always wait for the snapshot to
4529 * complete before returning.
4530 *
4531 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4532 */
4533 int cmd_snapshot_record(struct ltt_session *session,
4534 struct lttng_snapshot_output *output, int wait)
4535 {
4536 enum lttng_error_code cmd_ret = LTTNG_OK;
4537 int ret;
4538 unsigned int use_tmp_output = 0;
4539 struct snapshot_output tmp_output;
4540 unsigned int snapshot_success = 0;
4541 char datetime[16];
4542
4543 assert(session);
4544 assert(output);
4545
4546 DBG("Cmd snapshot record for session %s", session->name);
4547
4548 /* Get the datetime for the snapshot output directory. */
4549 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4550 sizeof(datetime));
4551 if (!ret) {
4552 cmd_ret = LTTNG_ERR_INVALID;
4553 goto error;
4554 }
4555
4556 /*
4557 * Permission denied to create an output if the session is not
4558 * set in no output mode.
4559 */
4560 if (session->output_traces) {
4561 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4562 goto error;
4563 }
4564
4565 /* The session needs to be started at least once. */
4566 if (!session->has_been_started) {
4567 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4568 goto error;
4569 }
4570
4571 /* Use temporary output for the session. */
4572 if (*output->ctrl_url != '\0') {
4573 ret = snapshot_output_init(session, output->max_size,
4574 output->name,
4575 output->ctrl_url, output->data_url,
4576 session->consumer,
4577 &tmp_output, NULL);
4578 if (ret < 0) {
4579 if (ret == -ENOMEM) {
4580 cmd_ret = LTTNG_ERR_NOMEM;
4581 } else {
4582 cmd_ret = LTTNG_ERR_INVALID;
4583 }
4584 goto error;
4585 }
4586 /* Use the global session count for the temporary snapshot. */
4587 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
4588
4589 /* Use the global datetime */
4590 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
4591 use_tmp_output = 1;
4592 }
4593
4594 if (use_tmp_output) {
4595 cmd_ret = snapshot_record(session, &tmp_output, wait);
4596 if (cmd_ret != LTTNG_OK) {
4597 goto error;
4598 }
4599 snapshot_success = 1;
4600 } else {
4601 struct snapshot_output *sout;
4602 struct lttng_ht_iter iter;
4603
4604 rcu_read_lock();
4605 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4606 &iter.iter, sout, node.node) {
4607 /*
4608 * Make a local copy of the output and assign the
4609 * possible temporary value given by the caller.
4610 */
4611 memcpy(&tmp_output, sout, sizeof(tmp_output));
4612
4613 if (output->max_size != (uint64_t) -1ULL) {
4614 tmp_output.max_size = output->max_size;
4615 }
4616
4617 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
4618 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
4619
4620 /* Use temporary name. */
4621 if (*output->name != '\0') {
4622 if (lttng_strncpy(tmp_output.name, output->name,
4623 sizeof(tmp_output.name))) {
4624 cmd_ret = LTTNG_ERR_INVALID;
4625 rcu_read_unlock();
4626 goto error;
4627 }
4628 }
4629
4630 cmd_ret = snapshot_record(session, &tmp_output, wait);
4631 if (cmd_ret != LTTNG_OK) {
4632 rcu_read_unlock();
4633 goto error;
4634 }
4635 snapshot_success = 1;
4636 }
4637 rcu_read_unlock();
4638 }
4639
4640 if (snapshot_success) {
4641 session->snapshot.nb_snapshot++;
4642 } else {
4643 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4644 }
4645
4646 error:
4647 return cmd_ret;
4648 }
4649
4650 /*
4651 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4652 */
4653 int cmd_set_session_shm_path(struct ltt_session *session,
4654 const char *shm_path)
4655 {
4656 /* Safety net */
4657 assert(session);
4658
4659 /*
4660 * Can only set shm path before session is started.
4661 */
4662 if (session->has_been_started) {
4663 return LTTNG_ERR_SESSION_STARTED;
4664 }
4665
4666 strncpy(session->shm_path, shm_path,
4667 sizeof(session->shm_path));
4668 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4669
4670 return 0;
4671 }
4672
4673 /*
4674 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4675 *
4676 * Ask the consumer to rotate the session output directory.
4677 * The session lock must be held.
4678 *
4679 * Returns LTTNG_OK on success or else a negative LTTng error code.
4680 */
4681 int cmd_rotate_session(struct ltt_session *session,
4682 struct lttng_rotate_session_return *rotate_return)
4683 {
4684 int ret;
4685 uint64_t ongoing_rotation_chunk_id;
4686 enum lttng_error_code cmd_ret = LTTNG_OK;
4687 struct lttng_trace_chunk *chunk_being_archived = NULL;
4688 struct lttng_trace_chunk *new_trace_chunk = NULL;
4689 enum lttng_trace_chunk_status chunk_status;
4690
4691 assert(session);
4692
4693 if (!session->has_been_started) {
4694 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4695 goto end;
4696 }
4697
4698 if (session->live_timer || !session->output_traces) {
4699 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4700 goto end;
4701 }
4702
4703 /* Unsupported feature in lttng-relayd before 2.11. */
4704 if (session->consumer->type == CONSUMER_DST_NET &&
4705 (session->consumer->relay_major_version == 2 &&
4706 session->consumer->relay_minor_version < 11)) {
4707 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4708 goto end;
4709 }
4710
4711 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4712 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
4713 session->name);
4714 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
4715 goto end;
4716 }
4717
4718 /*
4719 * After a stop, we only allow one rotation to occur, the other ones are
4720 * useless until a new start.
4721 */
4722 if (session->rotated_after_last_stop) {
4723 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4724 session->name);
4725 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4726 goto end;
4727 }
4728
4729 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
4730
4731 if (session->active) {
4732 new_trace_chunk = session_create_new_trace_chunk(session,
4733 NULL, NULL);
4734 if (!new_trace_chunk) {
4735 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
4736 goto error;
4737 }
4738 }
4739
4740 /* The current trace chunk becomes the chunk being archived. */
4741 ret = session_set_trace_chunk(session, new_trace_chunk,
4742 &chunk_being_archived);
4743 if (ret) {
4744 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4745 goto error;
4746 }
4747
4748 assert(chunk_being_archived);
4749 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
4750 &ongoing_rotation_chunk_id);
4751 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
4752
4753 chunk_status = lttng_trace_chunk_set_close_command(
4754 chunk_being_archived,
4755 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
4756 if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
4757 cmd_ret = LTTNG_ERR_FATAL;
4758 goto error;
4759 }
4760
4761 if (session->kernel_session) {
4762 cmd_ret = kernel_rotate_session(session);
4763 if (cmd_ret != LTTNG_OK) {
4764 goto error;
4765 }
4766 }
4767 if (session->ust_session) {
4768 cmd_ret = ust_app_rotate_session(session);
4769 if (cmd_ret != LTTNG_OK) {
4770 goto error;
4771 }
4772 }
4773
4774 ret = session_close_trace_chunk(session, chunk_being_archived);
4775 if (ret) {
4776 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4777 goto error;
4778 }
4779
4780 ret = timer_session_rotation_pending_check_start(session,
4781 DEFAULT_ROTATE_PENDING_TIMER);
4782 if (ret) {
4783 cmd_ret = LTTNG_ERR_UNK;
4784 goto error;
4785 }
4786
4787 if (!session->active) {
4788 session->rotated_after_last_stop = true;
4789 }
4790
4791 if (rotate_return) {
4792 rotate_return->rotation_id = ongoing_rotation_chunk_id;
4793 }
4794
4795 session->chunk_being_archived = chunk_being_archived;
4796 chunk_being_archived = NULL;
4797 ret = notification_thread_command_session_rotation_ongoing(
4798 notification_thread_handle,
4799 session->name, session->uid, session->gid,
4800 ongoing_rotation_chunk_id);
4801 if (ret != LTTNG_OK) {
4802 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
4803 session->name);
4804 cmd_ret = ret;
4805 }
4806
4807 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
4808 session->name, ongoing_rotation_chunk_id);
4809 end:
4810 lttng_trace_chunk_put(new_trace_chunk);
4811 lttng_trace_chunk_put(chunk_being_archived);
4812 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
4813 return ret;
4814 error:
4815 if (session_reset_rotation_state(session,
4816 LTTNG_ROTATION_STATE_ERROR)) {
4817 ERR("Failed to reset rotation state of session \"%s\"",
4818 session->name);
4819 }
4820 goto end;
4821 }
4822
4823 /*
4824 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
4825 *
4826 * Check if the session has finished its rotation.
4827 *
4828 * Return LTTNG_OK on success or else an LTTNG_ERR code.
4829 */
4830 int cmd_rotate_get_info(struct ltt_session *session,
4831 struct lttng_rotation_get_info_return *info_return,
4832 uint64_t rotation_id)
4833 {
4834 enum lttng_error_code cmd_ret = LTTNG_OK;
4835 enum lttng_rotation_state rotation_state;
4836
4837 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
4838 session->most_recent_chunk_id.value);
4839
4840 if (session->chunk_being_archived) {
4841 enum lttng_trace_chunk_status chunk_status;
4842 uint64_t chunk_id;
4843
4844 chunk_status = lttng_trace_chunk_get_id(
4845 session->chunk_being_archived,
4846 &chunk_id);
4847 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
4848
4849 rotation_state = rotation_id == chunk_id ?
4850 LTTNG_ROTATION_STATE_ONGOING :
4851 LTTNG_ROTATION_STATE_EXPIRED;
4852 } else {
4853 if (session->last_archived_chunk_id.is_set &&
4854 rotation_id != session->last_archived_chunk_id.value) {
4855 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
4856 } else {
4857 rotation_state = session->rotation_state;
4858 }
4859 }
4860
4861 switch (rotation_state) {
4862 case LTTNG_ROTATION_STATE_NO_ROTATION:
4863 DBG("Reporting that no rotation has occured within the lifetime of session \"%s\"",
4864 session->name);
4865 goto end;
4866 case LTTNG_ROTATION_STATE_EXPIRED:
4867 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
4868 rotation_id, session->name);
4869 break;
4870 case LTTNG_ROTATION_STATE_ONGOING:
4871 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
4872 rotation_id, session->name);
4873 break;
4874 case LTTNG_ROTATION_STATE_COMPLETED:
4875 {
4876 int fmt_ret;
4877 char *chunk_path;
4878 char *current_tracing_path_reply;
4879 size_t current_tracing_path_reply_len;
4880
4881 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
4882 rotation_id, session->name);
4883
4884 switch (session_get_consumer_destination_type(session)) {
4885 case CONSUMER_DST_LOCAL:
4886 current_tracing_path_reply =
4887 info_return->location.local.absolute_path;
4888 current_tracing_path_reply_len =
4889 sizeof(info_return->location.local.absolute_path);
4890 info_return->location_type =
4891 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
4892 break;
4893 case CONSUMER_DST_NET:
4894 current_tracing_path_reply =
4895 info_return->location.relay.relative_path;
4896 current_tracing_path_reply_len =
4897 sizeof(info_return->location.relay.relative_path);
4898 /* Currently the only supported relay protocol. */
4899 info_return->location.relay.protocol =
4900 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
4901
4902 fmt_ret = lttng_strncpy(info_return->location.relay.host,
4903 session_get_net_consumer_hostname(session),
4904 sizeof(info_return->location.relay.host));
4905 if (fmt_ret) {
4906 ERR("Failed to copy host name to rotate_get_info reply");
4907 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
4908 cmd_ret = LTTNG_ERR_SET_URL;
4909 goto end;
4910 }
4911
4912 session_get_net_consumer_ports(session,
4913 &info_return->location.relay.ports.control,
4914 &info_return->location.relay.ports.data);
4915 info_return->location_type =
4916 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
4917 break;
4918 default:
4919 abort();
4920 }
4921 fmt_ret = asprintf(&chunk_path,
4922 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
4923 session_get_base_path(session),
4924 session->last_archived_chunk_name);
4925 if (fmt_ret == -1) {
4926 PERROR("Failed to format the path of the last archived trace chunk");
4927 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
4928 cmd_ret = LTTNG_ERR_UNK;
4929 goto end;
4930 }
4931
4932 fmt_ret = lttng_strncpy(current_tracing_path_reply,
4933 chunk_path, current_tracing_path_reply_len);
4934 free(chunk_path);
4935 if (fmt_ret) {
4936 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
4937 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
4938 cmd_ret = LTTNG_ERR_UNK;
4939 goto end;
4940 }
4941
4942 break;
4943 }
4944 case LTTNG_ROTATION_STATE_ERROR:
4945 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
4946 rotation_id, session->name);
4947 break;
4948 default:
4949 abort();
4950 }
4951
4952 cmd_ret = LTTNG_OK;
4953 end:
4954 info_return->status = (int32_t) rotation_state;
4955 return cmd_ret;
4956 }
4957
4958 /*
4959 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
4960 *
4961 * Configure the automatic rotation parameters.
4962 * 'activate' to true means activate the rotation schedule type with 'new_value'.
4963 * 'activate' to false means deactivate the rotation schedule and validate that
4964 * 'new_value' has the same value as the currently active value.
4965 *
4966 * Return 0 on success or else a positive LTTNG_ERR code.
4967 */
4968 int cmd_rotation_set_schedule(struct ltt_session *session,
4969 bool activate, enum lttng_rotation_schedule_type schedule_type,
4970 uint64_t new_value,
4971 struct notification_thread_handle *notification_thread_handle)
4972 {
4973 int ret;
4974 uint64_t *parameter_value;
4975
4976 assert(session);
4977
4978 DBG("Cmd rotate set schedule session %s", session->name);
4979
4980 if (session->live_timer || !session->output_traces) {
4981 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
4982 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4983 goto end;
4984 }
4985
4986 switch (schedule_type) {
4987 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
4988 parameter_value = &session->rotate_size;
4989 break;
4990 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
4991 parameter_value = &session->rotate_timer_period;
4992 if (new_value >= UINT_MAX) {
4993 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
4994 new_value, UINT_MAX);
4995 ret = LTTNG_ERR_INVALID;
4996 goto end;
4997 }
4998 break;
4999 default:
5000 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5001 ret = LTTNG_ERR_INVALID;
5002 goto end;
5003 }
5004
5005 /* Improper use of the API. */
5006 if (new_value == -1ULL) {
5007 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5008 ret = LTTNG_ERR_INVALID;
5009 goto end;
5010 }
5011
5012 /*
5013 * As indicated in struct ltt_session's comments, a value of == 0 means
5014 * this schedule rotation type is not in use.
5015 *
5016 * Reject the command if we were asked to activate a schedule that was
5017 * already active.
5018 */
5019 if (activate && *parameter_value != 0) {
5020 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5021 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5022 goto end;
5023 }
5024
5025 /*
5026 * Reject the command if we were asked to deactivate a schedule that was
5027 * not active.
5028 */
5029 if (!activate && *parameter_value == 0) {
5030 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5031 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5032 goto end;
5033 }
5034
5035 /*
5036 * Reject the command if we were asked to deactivate a schedule that
5037 * doesn't exist.
5038 */
5039 if (!activate && *parameter_value != new_value) {
5040 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5041 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5042 goto end;
5043 }
5044
5045 *parameter_value = activate ? new_value : 0;
5046
5047 switch (schedule_type) {
5048 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5049 if (activate && session->active) {
5050 /*
5051 * Only start the timer if the session is active,
5052 * otherwise it will be started when the session starts.
5053 */
5054 ret = timer_session_rotation_schedule_timer_start(
5055 session, new_value);
5056 if (ret) {
5057 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5058 ret = LTTNG_ERR_UNK;
5059 goto end;
5060 }
5061 } else {
5062 ret = timer_session_rotation_schedule_timer_stop(
5063 session);
5064 if (ret) {
5065 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5066 ret = LTTNG_ERR_UNK;
5067 goto end;
5068 }
5069 }
5070 break;
5071 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5072 if (activate) {
5073 ret = subscribe_session_consumed_size_rotation(session,
5074 new_value, notification_thread_handle);
5075 if (ret) {
5076 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5077 ret = LTTNG_ERR_UNK;
5078 goto end;
5079 }
5080 } else {
5081 ret = unsubscribe_session_consumed_size_rotation(session,
5082 notification_thread_handle);
5083 if (ret) {
5084 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5085 ret = LTTNG_ERR_UNK;
5086 goto end;
5087 }
5088
5089 }
5090 break;
5091 default:
5092 /* Would have been caught before. */
5093 abort();
5094 }
5095
5096 ret = LTTNG_OK;
5097
5098 goto end;
5099
5100 end:
5101 return ret;
5102 }
5103
5104 /* Wait for a given path to be removed before continuing. */
5105 static enum lttng_error_code wait_on_path(void *path_data)
5106 {
5107 const char *shm_path = path_data;
5108
5109 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5110 shm_path);
5111 while (true) {
5112 int ret;
5113 struct stat st;
5114
5115 ret = stat(shm_path, &st);
5116 if (ret) {
5117 if (errno != ENOENT) {
5118 PERROR("stat() returned an error while checking for the existence of the shm path");
5119 } else {
5120 DBG("shm path no longer exists, completing the destruction of session");
5121 }
5122 break;
5123 } else {
5124 if (!S_ISDIR(st.st_mode)) {
5125 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5126 shm_path);
5127 break;
5128 }
5129 }
5130 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5131 }
5132 return LTTNG_OK;
5133 }
5134
5135 /*
5136 * Returns a pointer to a handler to run on completion of a command.
5137 * Returns NULL if no handler has to be run for the last command executed.
5138 */
5139 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5140 {
5141 struct cmd_completion_handler *handler = current_completion_handler;
5142
5143 current_completion_handler = NULL;
5144 return handler;
5145 }
5146
5147 /*
5148 * Init command subsystem.
5149 */
5150 void cmd_init(void)
5151 {
5152 /*
5153 * Set network sequence index to 1 for streams to match a relayd
5154 * socket on the consumer side.
5155 */
5156 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5157 relayd_net_seq_idx = 1;
5158 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5159
5160 DBG("Command subsystem initialized");
5161 }
LTTng tools - Deliverables
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