Rename C++ header files to .hpp
[lttng-tools.git] / src / bin / lttng-relayd / session.cpp
1 /*
2 * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
3 * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
4 * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5 *
6 * SPDX-License-Identifier: GPL-2.0-only
7 *
8 */
9
10 #define _LGPL_SOURCE
11 #include <common/common.hpp>
12 #include <common/compat/path.hpp>
13 #include <common/fd-tracker/utils.hpp>
14 #include <common/time.hpp>
15 #include <common/utils.hpp>
16 #include <common/uuid.hpp>
17 #include <urcu/rculist.h>
18
19 #include <sys/stat.h>
20
21 #include "ctf-trace.hpp"
22 #include "lttng-relayd.hpp"
23 #include "session.hpp"
24 #include "sessiond-trace-chunks.hpp"
25 #include "stream.hpp"
26 #include <common/defaults.hpp>
27 #include "utils.hpp"
28
29 /* Global session id used in the session creation. */
30 static uint64_t last_relay_session_id;
31 static pthread_mutex_t last_relay_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
32
33 static int init_session_output_path_group_by_host(struct relay_session *session)
34 {
35 /*
36 * session_directory:
37 *
38 * if base_path is \0'
39 * hostname/session_name
40 * else
41 * hostname/base_path
42 */
43 char *session_directory = NULL;
44 int ret = 0;
45
46 if (session->output_path[0] != '\0') {
47 goto end;
48 }
49 /*
50 * If base path is set, it overrides the session name for the
51 * session relative base path. No timestamp is appended if the
52 * base path is overridden.
53 *
54 * If the session name already contains the creation time (e.g.
55 * auto-<timestamp>, don't append yet another timestamp after
56 * the session name in the generated path.
57 *
58 * Otherwise, generate the path with session_name-<timestamp>.
59 */
60 if (session->base_path[0] != '\0') {
61 ret = asprintf(&session_directory, "%s/%s", session->hostname,
62 session->base_path);
63 } else if (session->session_name_contains_creation_time) {
64 ret = asprintf(&session_directory, "%s/%s", session->hostname,
65 session->session_name);
66 } else {
67 char session_creation_datetime[DATETIME_STR_LEN];
68
69 ret = time_to_datetime_str(
70 LTTNG_OPTIONAL_GET(session->creation_time),
71 session_creation_datetime,
72 sizeof(session_creation_datetime));
73 if (ret) {
74 ERR("Failed to format session creation timestamp while initializing session output directory handle");
75 ret = -1;
76 goto end;
77 }
78
79 ret = asprintf(&session_directory, "%s/%s-%s",
80 session->hostname, session->session_name,
81 session_creation_datetime);
82 }
83 if (ret < 0) {
84 PERROR("Failed to format session directory name");
85 goto end;
86 }
87
88 if (strlen(session_directory) >= LTTNG_PATH_MAX) {
89 ERR("Session output directory exceeds maximal length");
90 ret = -1;
91 goto end;
92 }
93 strcpy(session->output_path, session_directory);
94 ret = 0;
95
96 end:
97 free(session_directory);
98 return ret;
99 }
100
101 static int init_session_output_path_group_by_session(
102 struct relay_session *session)
103 {
104 /*
105 * session_directory:
106 *
107 * session_name/hostname-creation_time/base_path
108 *
109 * For session name including the datetime, use it as the complete name
110 * since. Do not perform modification on it since the datetime is an
111 * integral part of the name and how a user identify a session.
112 */
113 int ret = 0;
114 char *session_directory = NULL;
115 char creation_datetime[DATETIME_STR_LEN];
116
117 if (session->output_path[0] != '\0') {
118 /* output_path as been generated already */
119 goto end;
120 }
121
122 ret = time_to_datetime_str(LTTNG_OPTIONAL_GET(session->creation_time),
123 creation_datetime, sizeof(creation_datetime));
124 if (ret) {
125 ERR("Failed to format session creation timestamp while initializing session output directory handle");
126 ret = -1;
127 goto end;
128 }
129
130 ret = asprintf(&session_directory, "%s/%s-%s%s%s",
131 session->session_name, session->hostname,
132 creation_datetime,
133 session->base_path[0] != '\0' ? "/" : "",
134 session->base_path);
135 if (ret < 0) {
136 PERROR("Failed to format session directory name");
137 goto end;
138 }
139
140 if (strlen(session_directory) >= LTTNG_PATH_MAX) {
141 ERR("Session output directory exceeds maximal length");
142 ret = -1;
143 goto end;
144 }
145
146 strcpy(session->output_path, session_directory);
147 ret = 0;
148
149 end:
150 free(session_directory);
151 return ret;
152 }
153
154 static int init_session_output_path(struct relay_session *session)
155 {
156 int ret;
157
158 switch (opt_group_output_by) {
159 case RELAYD_GROUP_OUTPUT_BY_HOST:
160 ret = init_session_output_path_group_by_host(session);
161 break;
162 case RELAYD_GROUP_OUTPUT_BY_SESSION:
163 ret = init_session_output_path_group_by_session(session);
164 break;
165 case RELAYD_GROUP_OUTPUT_BY_UNKNOWN:
166 default:
167 abort();
168 break;
169 }
170
171 return ret;
172 }
173
174 static struct lttng_directory_handle *session_create_output_directory_handle(
175 struct relay_session *session)
176 {
177 int ret;
178 /*
179 * relayd_output_path/session_directory
180 * e.g. /home/user/lttng-traces/hostname/session_name
181 */
182 char *full_session_path = NULL;
183 struct lttng_directory_handle *handle = NULL;
184
185 pthread_mutex_lock(&session->lock);
186 full_session_path = create_output_path(session->output_path);
187 if (!full_session_path) {
188 goto end;
189 }
190
191 ret = utils_mkdir_recursive(
192 full_session_path, S_IRWXU | S_IRWXG, -1, -1);
193 if (ret) {
194 ERR("Failed to create session output path \"%s\"",
195 full_session_path);
196 goto end;
197 }
198
199 handle = fd_tracker_create_directory_handle(the_fd_tracker, full_session_path);
200 end:
201 pthread_mutex_unlock(&session->lock);
202 free(full_session_path);
203 return handle;
204 }
205
206 static int session_set_anonymous_chunk(struct relay_session *session)
207 {
208 int ret = 0;
209 struct lttng_trace_chunk *chunk = NULL;
210 enum lttng_trace_chunk_status status;
211 struct lttng_directory_handle *output_directory;
212
213 output_directory = session_create_output_directory_handle(session);
214 if (!output_directory) {
215 goto end;
216 }
217
218 chunk = lttng_trace_chunk_create_anonymous();
219 if (!chunk) {
220 goto end;
221 }
222
223 lttng_trace_chunk_set_fd_tracker(chunk, the_fd_tracker);
224 status = lttng_trace_chunk_set_credentials_current_user(chunk);
225 if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
226 ret = -1;
227 goto end;
228 }
229
230 status = lttng_trace_chunk_set_as_owner(chunk, output_directory);
231 if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
232 ret = -1;
233 goto end;
234 }
235
236 session->current_trace_chunk = chunk;
237 chunk = NULL;
238 end:
239 lttng_trace_chunk_put(chunk);
240 lttng_directory_handle_put(output_directory);
241 return ret;
242 }
243
244 /*
245 * Check if a name is safe to use in a path.
246 *
247 * A name that is deemed "path-safe":
248 * - Does not contains a path separator (/ or \, platform dependant),
249 * - Does not start with a '.' (hidden file/folder),
250 * - Is not empty.
251 */
252 static bool is_name_path_safe(const char *name)
253 {
254 const size_t name_len = strlen(name);
255
256 /* Not empty. */
257 if (name_len == 0) {
258 WARN("An empty name is not allowed to be used in a path");
259 return false;
260 }
261 /* Does not start with '.'. */
262 if (name[0] == '.') {
263 WARN("Name \"%s\" is not allowed to be used in a path since it starts with '.'", name);
264 return false;
265 }
266 /* Does not contain a path-separator. */
267 if (strchr(name, LTTNG_PATH_SEPARATOR)) {
268 WARN("Name \"%s\" is not allowed to be used in a path since it contains a path separator", name);
269 return false;
270 }
271
272 return true;
273 }
274
275 /*
276 * Create a new session by assigning a new session ID.
277 *
278 * Return allocated session or else NULL.
279 */
280 struct relay_session *session_create(const char *session_name,
281 const char *hostname, const char *base_path,
282 uint32_t live_timer,
283 bool snapshot,
284 const lttng_uuid sessiond_uuid,
285 const uint64_t *id_sessiond,
286 const uint64_t *current_chunk_id,
287 const time_t *creation_time,
288 uint32_t major,
289 uint32_t minor,
290 bool session_name_contains_creation_time)
291 {
292 int ret;
293 struct relay_session *session = NULL;
294
295 LTTNG_ASSERT(session_name);
296 LTTNG_ASSERT(hostname);
297 LTTNG_ASSERT(base_path);
298
299 if (!is_name_path_safe(session_name)) {
300 ERR("Refusing to create session as the provided session name is not path-safe");
301 goto error;
302 }
303 if (!is_name_path_safe(hostname)) {
304 ERR("Refusing to create session as the provided hostname is not path-safe");
305 goto error;
306 }
307 if (strstr(base_path, "../")) {
308 ERR("Invalid session base path walks up the path hierarchy: \"%s\"",
309 base_path);
310 goto error;
311 }
312
313 session = (relay_session *) zmalloc(sizeof(*session));
314 if (!session) {
315 PERROR("Failed to allocate session");
316 goto error;
317 }
318
319 pthread_mutex_lock(&last_relay_session_id_lock);
320 session->id = ++last_relay_session_id;
321 pthread_mutex_unlock(&last_relay_session_id_lock);
322
323 lttng_ht_node_init_u64(&session->session_n, session->id);
324 urcu_ref_init(&session->ref);
325 CDS_INIT_LIST_HEAD(&session->recv_list);
326 pthread_mutex_init(&session->lock, NULL);
327 pthread_mutex_init(&session->recv_list_lock, NULL);
328
329 if (lttng_strncpy(session->session_name, session_name,
330 sizeof(session->session_name))) {
331 WARN("Session name exceeds maximal allowed length");
332 goto error;
333 }
334 if (lttng_strncpy(session->hostname, hostname,
335 sizeof(session->hostname))) {
336 WARN("Hostname exceeds maximal allowed length");
337 goto error;
338 }
339 if (lttng_strncpy(session->base_path, base_path,
340 sizeof(session->base_path))) {
341 WARN("Base path exceeds maximal allowed length");
342 goto error;
343 }
344 if (creation_time) {
345 LTTNG_OPTIONAL_SET(&session->creation_time, *creation_time);
346 } else {
347 LTTNG_OPTIONAL_SET(&session->creation_time, time(NULL));
348 if (session->creation_time.value == (time_t) -1) {
349 PERROR("Failed to sample session creation time");
350 goto error;
351 }
352 }
353 session->session_name_contains_creation_time =
354 session_name_contains_creation_time;
355
356 session->ctf_traces_ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
357 if (!session->ctf_traces_ht) {
358 goto error;
359 }
360
361 session->major = major;
362 session->minor = minor;
363
364 session->live_timer = live_timer;
365 session->snapshot = snapshot;
366 lttng_uuid_copy(session->sessiond_uuid, sessiond_uuid);
367
368 if (id_sessiond) {
369 LTTNG_OPTIONAL_SET(&session->id_sessiond, *id_sessiond);
370 }
371
372 if (major == 2 && minor >= 11) {
373 /* Only applies for 2.11+ peers using trace chunks. */
374 ret = init_session_output_path(session);
375 if (ret) {
376 goto error;
377 }
378 }
379
380 ret = sessiond_trace_chunk_registry_session_created(
381 sessiond_trace_chunk_registry, sessiond_uuid);
382 if (ret) {
383 goto error;
384 }
385
386 if (id_sessiond && current_chunk_id) {
387 enum lttng_trace_chunk_status chunk_status;
388 struct lttng_directory_handle *session_output_directory;
389
390 session->current_trace_chunk =
391 sessiond_trace_chunk_registry_get_chunk(
392 sessiond_trace_chunk_registry,
393 session->sessiond_uuid,
394 session->id_sessiond.value,
395 *current_chunk_id);
396 if (!session->current_trace_chunk) {
397 char uuid_str[LTTNG_UUID_STR_LEN];
398
399 lttng_uuid_to_str(sessiond_uuid, uuid_str);
400 ERR("Could not find trace chunk: sessiond = {%s}, sessiond session id = %" PRIu64 ", trace chunk id = %" PRIu64,
401 uuid_str, *id_sessiond,
402 *current_chunk_id);
403 goto error;
404 }
405
406 chunk_status = lttng_trace_chunk_get_session_output_directory_handle(
407 session->current_trace_chunk,
408 &session_output_directory);
409 if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
410 goto error;
411 }
412
413 LTTNG_ASSERT(session_output_directory);
414 session->output_directory = session_output_directory;
415 } else if (!id_sessiond) {
416 /*
417 * Pre-2.11 peers will not announce trace chunks. An
418 * anonymous trace chunk which will remain set for the
419 * duration of the session is created.
420 */
421 ret = session_set_anonymous_chunk(session);
422 if (ret) {
423 goto error;
424 }
425 } else {
426 session->output_directory =
427 session_create_output_directory_handle(session);
428 if (!session->output_directory) {
429 goto error;
430 }
431 }
432
433 lttng_ht_add_unique_u64(sessions_ht, &session->session_n);
434 return session;
435
436 error:
437 session_put(session);
438 return NULL;
439 }
440
441 /* Should be called with RCU read-side lock held. */
442 bool session_get(struct relay_session *session)
443 {
444 return urcu_ref_get_unless_zero(&session->ref);
445 }
446
447 /*
448 * Lookup a session within the session hash table using the session id
449 * as key. A session reference is taken when a session is returned.
450 * session_put() must be called on that session.
451 *
452 * Return session or NULL if not found.
453 */
454 struct relay_session *session_get_by_id(uint64_t id)
455 {
456 struct relay_session *session = NULL;
457 struct lttng_ht_node_u64 *node;
458 struct lttng_ht_iter iter;
459
460 rcu_read_lock();
461 lttng_ht_lookup(sessions_ht, &id, &iter);
462 node = lttng_ht_iter_get_node_u64(&iter);
463 if (!node) {
464 DBG("Session find by ID %" PRIu64 " id NOT found", id);
465 goto end;
466 }
467 session = caa_container_of(node, struct relay_session, session_n);
468 DBG("Session find by ID %" PRIu64 " id found", id);
469 if (!session_get(session)) {
470 session = NULL;
471 }
472 end:
473 rcu_read_unlock();
474 return session;
475 }
476
477 /*
478 * Check if any of the relay sessions originating from the same
479 * session daemon session have the 'ongoing_rotation' state set.
480 *
481 * The caller must hold the lock of session.
482 */
483 bool session_has_ongoing_rotation(const struct relay_session *session)
484 {
485 bool ongoing_rotation = false;
486 struct lttng_ht_iter iter;
487 struct relay_session *iterated_session;
488
489 ASSERT_LOCKED(session->lock);
490
491 if (!session->id_sessiond.is_set) {
492 /*
493 * The peer that created this session is too old to
494 * support rotations; we can assume no rotations are ongoing.
495 */
496 goto end;
497 }
498
499 if (session->ongoing_rotation) {
500 ongoing_rotation = true;
501 goto end;
502 }
503
504 rcu_read_lock();
505 /*
506 * Sample the 'ongoing_rotation' status of all relay sessions that
507 * originate from the same session daemon session.
508 */
509 cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, iterated_session,
510 session_n.node) {
511 if (!session_get(iterated_session)) {
512 continue;
513 }
514
515 if (session == iterated_session) {
516 /* Skip this session. */
517 goto next_session_no_unlock;
518 }
519
520 pthread_mutex_lock(&iterated_session->lock);
521
522 if (!iterated_session->id_sessiond.is_set) {
523 /*
524 * Session belongs to a peer that doesn't support
525 * rotations.
526 */
527 goto next_session;
528 }
529
530 if (!lttng_uuid_is_equal(session->sessiond_uuid,
531 iterated_session->sessiond_uuid)) {
532 /* Sessions do not originate from the same sessiond. */
533 goto next_session;
534 }
535
536 if (LTTNG_OPTIONAL_GET(session->id_sessiond) !=
537 LTTNG_OPTIONAL_GET(iterated_session->id_sessiond)) {
538 /*
539 * Sessions do not originate from the same sessiond
540 * session.
541 */
542 goto next_session;
543 }
544
545 ongoing_rotation = iterated_session->ongoing_rotation;
546
547 next_session:
548 pthread_mutex_unlock(&iterated_session->lock);
549 next_session_no_unlock:
550 session_put(iterated_session);
551
552 if (ongoing_rotation) {
553 break;
554 }
555 }
556 rcu_read_unlock();
557
558 end:
559 return ongoing_rotation;
560 }
561
562 static void rcu_destroy_session(struct rcu_head *rcu_head)
563 {
564 struct relay_session *session =
565 caa_container_of(rcu_head, struct relay_session,
566 rcu_node);
567 /*
568 * Since each trace has a reference on the session, it means
569 * that if we are at the point where we teardown the session, no
570 * trace belonging to that session exist at this point.
571 * Calling lttng_ht_destroy in call_rcu worker thread so we
572 * don't hold the RCU read-side lock while calling it.
573 */
574 lttng_ht_destroy(session->ctf_traces_ht);
575 free(session);
576 }
577
578 /*
579 * Delete session from the given hash table.
580 *
581 * Return lttng ht del error code being 0 on success and 1 on failure.
582 */
583 static int session_delete(struct relay_session *session)
584 {
585 struct lttng_ht_iter iter;
586
587 iter.iter.node = &session->session_n.node;
588 return lttng_ht_del(sessions_ht, &iter);
589 }
590
591
592 static void destroy_session(struct relay_session *session)
593 {
594 int ret;
595
596 ret = session_delete(session);
597 LTTNG_ASSERT(!ret);
598 lttng_trace_chunk_put(session->current_trace_chunk);
599 session->current_trace_chunk = NULL;
600 lttng_trace_chunk_put(session->pending_closure_trace_chunk);
601 session->pending_closure_trace_chunk = NULL;
602 ret = sessiond_trace_chunk_registry_session_destroyed(
603 sessiond_trace_chunk_registry, session->sessiond_uuid);
604 LTTNG_ASSERT(!ret);
605 lttng_directory_handle_put(session->output_directory);
606 session->output_directory = NULL;
607 call_rcu(&session->rcu_node, rcu_destroy_session);
608 }
609
610 static void session_release(struct urcu_ref *ref)
611 {
612 struct relay_session *session =
613 caa_container_of(ref, struct relay_session, ref);
614
615 destroy_session(session);
616 }
617
618 void session_put(struct relay_session *session)
619 {
620 if (!session) {
621 return;
622 }
623 rcu_read_lock();
624 urcu_ref_put(&session->ref, session_release);
625 rcu_read_unlock();
626 }
627
628 int session_close(struct relay_session *session)
629 {
630 int ret = 0;
631 struct ctf_trace *trace;
632 struct lttng_ht_iter iter;
633 struct relay_stream *stream;
634
635 pthread_mutex_lock(&session->lock);
636 DBG("closing session %" PRIu64 ": is conn already closed %d",
637 session->id, session->connection_closed);
638 session->connection_closed = true;
639 pthread_mutex_unlock(&session->lock);
640
641 rcu_read_lock();
642 cds_lfht_for_each_entry(session->ctf_traces_ht->ht,
643 &iter.iter, trace, node.node) {
644 ret = ctf_trace_close(trace);
645 if (ret) {
646 goto rcu_unlock;
647 }
648 }
649 cds_list_for_each_entry_rcu(stream, &session->recv_list,
650 recv_node) {
651 /* Close streams which have not been published yet. */
652 try_stream_close(stream);
653 }
654 rcu_unlock:
655 rcu_read_unlock();
656 if (ret) {
657 return ret;
658 }
659 /* Put self-reference from create. */
660 session_put(session);
661 return ret;
662 }
663
664 int session_abort(struct relay_session *session)
665 {
666 int ret = 0;
667
668 if (!session) {
669 return 0;
670 }
671
672 pthread_mutex_lock(&session->lock);
673 DBG("aborting session %" PRIu64, session->id);
674 session->aborted = true;
675 pthread_mutex_unlock(&session->lock);
676 return ret;
677 }
678
679 void print_sessions(void)
680 {
681 struct lttng_ht_iter iter;
682 struct relay_session *session;
683
684 if (!sessions_ht) {
685 return;
686 }
687
688 rcu_read_lock();
689 cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, session,
690 session_n.node) {
691 if (!session_get(session)) {
692 continue;
693 }
694 DBG("session %p refcount %ld session %" PRIu64,
695 session,
696 session->ref.refcount,
697 session->id);
698 session_put(session);
699 }
700 rcu_read_unlock();
701 }
This page took 0.043886 seconds and 5 git commands to generate.