Fix: Namespace lttng-viewer-abi
[lttng-tools.git] / src / bin / lttng-relayd / live.c
CommitLineData
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1/*
2 * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
3 * David Goulet <dgoulet@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as 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
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19#define _GNU_SOURCE
20#include <getopt.h>
21#include <grp.h>
22#include <limits.h>
23#include <pthread.h>
24#include <signal.h>
25#include <stdio.h>
26#include <stdlib.h>
27#include <string.h>
28#include <sys/mman.h>
29#include <sys/mount.h>
30#include <sys/resource.h>
31#include <sys/socket.h>
32#include <sys/stat.h>
33#include <sys/types.h>
34#include <sys/wait.h>
35#include <inttypes.h>
36#include <urcu/futex.h>
37#include <urcu/uatomic.h>
38#include <unistd.h>
39#include <fcntl.h>
40#include <config.h>
41
42#include <lttng/lttng.h>
43#include <common/common.h>
44#include <common/compat/poll.h>
45#include <common/compat/socket.h>
46#include <common/defaults.h>
47#include <common/futex.h>
2f8f53af 48#include <common/index/index.h>
d3e2ba59
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49#include <common/sessiond-comm/sessiond-comm.h>
50#include <common/sessiond-comm/inet.h>
51#include <common/sessiond-comm/relayd.h>
52#include <common/uri.h>
53#include <common/utils.h>
54
55#include "cmd.h"
56#include "live.h"
57#include "lttng-relayd.h"
d3e2ba59 58#include "utils.h"
eea7556c 59#include "health-relayd.h"
9b5e0863 60#include "testpoint.h"
2f8f53af 61#include "viewer-stream.h"
2a174661
DG
62#include "stream.h"
63#include "session.h"
64#include "ctf-trace.h"
58eb9381 65#include "connection.h"
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66
67static struct lttng_uri *live_uri;
68
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69/*
70 * This pipe is used to inform the worker thread that a command is queued and
71 * ready to be processed.
72 */
58eb9381 73static int live_conn_pipe[2] = { -1, -1 };
d3e2ba59
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74
75/* Shared between threads */
76static int live_dispatch_thread_exit;
77
78static pthread_t live_listener_thread;
79static pthread_t live_dispatcher_thread;
80static pthread_t live_worker_thread;
81
82/*
83 * Relay command queue.
84 *
85 * The live_thread_listener and live_thread_dispatcher communicate with this
86 * queue.
87 */
58eb9381 88static struct relay_conn_queue viewer_conn_queue;
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89
90static uint64_t last_relay_viewer_session_id;
91
92/*
93 * Cleanup the daemon
94 */
95static
96void cleanup(void)
97{
98 DBG("Cleaning up");
99
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100 free(live_uri);
101}
102
2f8f53af
DG
103/*
104 * Receive a request buffer using a given socket, destination allocated buffer
105 * of length size.
106 *
107 * Return the size of the received message or else a negative value on error
108 * with errno being set by recvmsg() syscall.
109 */
110static
111ssize_t recv_request(struct lttcomm_sock *sock, void *buf, size_t size)
112{
113 ssize_t ret;
114
115 assert(sock);
116 assert(buf);
117
118 ret = sock->ops->recvmsg(sock, buf, size, 0);
119 if (ret < 0 || ret != size) {
120 if (ret == 0) {
121 /* Orderly shutdown. Not necessary to print an error. */
122 DBG("Socket %d did an orderly shutdown", sock->fd);
123 } else {
124 ERR("Relay failed to receive request.");
125 }
126 ret = -1;
127 }
128
129 return ret;
130}
131
132/*
133 * Send a response buffer using a given socket, source allocated buffer of
134 * length size.
135 *
136 * Return the size of the sent message or else a negative value on error with
137 * errno being set by sendmsg() syscall.
138 */
139static
140ssize_t send_response(struct lttcomm_sock *sock, void *buf, size_t size)
141{
142 ssize_t ret;
143
144 assert(sock);
145 assert(buf);
146
147 ret = sock->ops->sendmsg(sock, buf, size, 0);
148 if (ret < 0) {
149 ERR("Relayd failed to send response.");
150 }
151
152 return ret;
153}
154
155/*
156 * Atomically check if new streams got added in the session since the last
157 * check and reset the flag to 0.
158 *
159 * Returns 1 if new streams got added, 0 if nothing changed, a negative value
160 * on error.
161 */
162static
163int check_new_streams(uint64_t session_id, struct lttng_ht *sessions_ht)
164{
165 int ret;
166 unsigned long current_val;
167 struct relay_session *session;
168
169 assert(sessions_ht);
170
171 session = session_find_by_id(sessions_ht, session_id);
172 if (!session) {
173 DBG("Relay session %" PRIu64 " not found", session_id);
174 ret = -1;
175 goto error;
176 }
177
178 current_val = uatomic_cmpxchg(&session->new_streams, 1, 0);
179 ret = current_val;
180
181error:
182 return ret;
183}
184
185/*
186 * Send viewer streams to the given socket. The ignore_sent_flag indicates if
187 * this function should ignore the sent flag or not.
188 *
189 * Return 0 on success or else a negative value.
190 */
191static
192ssize_t send_viewer_streams(struct lttcomm_sock *sock,
193 struct relay_session *session, unsigned int ignore_sent_flag)
194{
195 ssize_t ret;
196 struct lttng_viewer_stream send_stream;
197 struct lttng_ht_iter iter;
198 struct relay_viewer_stream *vstream;
199
200 assert(session);
201
202 rcu_read_lock();
203
204 cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter, vstream,
205 stream_n.node) {
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206 struct ctf_trace *ctf_trace;
207
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208 health_code_update();
209
210 /* Ignore if not the same session. */
211 if (vstream->session_id != session->id ||
212 (!ignore_sent_flag && vstream->sent_flag)) {
213 continue;
214 }
215
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216 ctf_trace = ctf_trace_find_by_path(session->ctf_traces_ht,
217 vstream->path_name);
218 assert(ctf_trace);
219
2f8f53af 220 send_stream.id = htobe64(vstream->stream_handle);
2a174661 221 send_stream.ctf_trace_id = htobe64(ctf_trace->id);
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222 send_stream.metadata_flag = htobe32(vstream->metadata_flag);
223 strncpy(send_stream.path_name, vstream->path_name,
224 sizeof(send_stream.path_name));
225 strncpy(send_stream.channel_name, vstream->channel_name,
226 sizeof(send_stream.channel_name));
227
228 DBG("Sending stream %" PRIu64 " to viewer", vstream->stream_handle);
229 ret = send_response(sock, &send_stream, sizeof(send_stream));
230 if (ret < 0) {
231 goto end_unlock;
232 }
233 vstream->sent_flag = 1;
234 }
235
236 ret = 0;
237
238end_unlock:
239 rcu_read_unlock();
240 return ret;
241}
242
243/*
244 * Create every viewer stream possible for the given session with the seek
245 * type. Three counters *can* be return which are in order the total amount of
246 * viewer stream of the session, the number of unsent stream and the number of
247 * stream created. Those counters can be NULL and thus will be ignored.
248 *
249 * Return 0 on success or else a negative value.
250 */
251static
252int make_viewer_streams(struct relay_session *session,
253 enum lttng_viewer_seek seek_t, uint32_t *nb_total, uint32_t *nb_unsent,
254 uint32_t *nb_created)
255{
256 int ret;
2f8f53af 257 struct lttng_ht_iter iter;
2a174661 258 struct ctf_trace *ctf_trace;
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259
260 assert(session);
261
262 /*
263 * This is to make sure we create viewer streams for a full received
264 * channel. For instance, if we have 8 streams for a channel that are
265 * concurrently being flagged ready, we can end up creating just a subset
266 * of the 8 streams (the ones that are flagged). This lock avoids this
267 * limbo state.
268 */
269 pthread_mutex_lock(&session->viewer_ready_lock);
270
271 /*
272 * Create viewer streams for relay streams that are ready to be used for a
273 * the given session id only.
274 */
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275 rcu_read_lock();
276 cds_lfht_for_each_entry(session->ctf_traces_ht->ht, &iter.iter, ctf_trace,
277 node.node) {
278 struct relay_stream *stream;
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279
280 health_code_update();
281
2a174661 282 if (ctf_trace->invalid_flag) {
2f8f53af
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283 continue;
284 }
285
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286 cds_list_for_each_entry(stream, &ctf_trace->stream_list, trace_list) {
287 struct relay_viewer_stream *vstream;
288
289 if (!stream->viewer_ready) {
290 continue;
291 }
292
293 vstream = viewer_stream_find_by_id(stream->stream_handle);
2f8f53af 294 if (!vstream) {
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295 vstream = viewer_stream_create(stream, seek_t, ctf_trace);
296 if (!vstream) {
297 ret = -1;
298 goto error_unlock;
299 }
300 /* Acquire reference to ctf_trace. */
301 ctf_trace_get_ref(ctf_trace);
302
303 if (nb_created) {
304 /* Update number of created stream counter. */
305 (*nb_created)++;
306 }
307 } else if (!vstream->sent_flag && nb_unsent) {
308 /* Update number of unsent stream counter. */
309 (*nb_unsent)++;
2f8f53af 310 }
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311 /* Update number of total stream counter. */
312 if (nb_total) {
313 (*nb_total)++;
2f8f53af 314 }
2f8f53af
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315 }
316 }
317
318 ret = 0;
319
320error_unlock:
2a174661 321 rcu_read_unlock();
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322 pthread_mutex_unlock(&session->viewer_ready_lock);
323 return ret;
324}
325
d3e2ba59
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326/*
327 * Write to writable pipe used to notify a thread.
328 */
329static
330int notify_thread_pipe(int wpipe)
331{
6cd525e8 332 ssize_t ret;
d3e2ba59 333
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MD
334 ret = lttng_write(wpipe, "!", 1);
335 if (ret < 1) {
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336 PERROR("write poll pipe");
337 }
338
6cd525e8 339 return (int) ret;
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340}
341
342/*
343 * Stop all threads by closing the thread quit pipe.
344 */
345static
346void stop_threads(void)
347{
348 int ret;
349
350 /* Stopping all threads */
351 DBG("Terminating all live threads");
2a174661 352 ret = notify_thread_pipe(live_conn_pipe[1]);
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353 if (ret < 0) {
354 ERR("write error on thread quit pipe");
355 }
356
357 /* Dispatch thread */
358 CMM_STORE_SHARED(live_dispatch_thread_exit, 1);
58eb9381 359 futex_nto1_wake(&viewer_conn_queue.futex);
d3e2ba59
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360}
361
d3e2ba59
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362/*
363 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
364 */
365static
366int create_thread_poll_set(struct lttng_poll_event *events, int size)
367{
368 int ret;
369
370 if (events == NULL || size == 0) {
371 ret = -1;
372 goto error;
373 }
374
375 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
376 if (ret < 0) {
377 goto error;
378 }
379
380 /* Add quit pipe */
2a174661 381 ret = lttng_poll_add(events, live_conn_pipe[0], LPOLLIN | LPOLLERR);
d3e2ba59
JD
382 if (ret < 0) {
383 goto error;
384 }
385
386 return 0;
387
388error:
389 return ret;
390}
391
392/*
393 * Check if the thread quit pipe was triggered.
394 *
395 * Return 1 if it was triggered else 0;
396 */
397static
2a174661 398int check_live_conn_pipe(int fd, uint32_t events)
d3e2ba59 399{
2a174661 400 if (fd == live_conn_pipe[0] && (events & LPOLLIN)) {
d3e2ba59
JD
401 return 1;
402 }
403
404 return 0;
405}
406
407/*
408 * Create and init socket from uri.
409 */
410static
411struct lttcomm_sock *init_socket(struct lttng_uri *uri)
412{
413 int ret;
414 struct lttcomm_sock *sock = NULL;
415
416 sock = lttcomm_alloc_sock_from_uri(uri);
417 if (sock == NULL) {
418 ERR("Allocating socket");
419 goto error;
420 }
421
422 ret = lttcomm_create_sock(sock);
423 if (ret < 0) {
424 goto error;
425 }
426 DBG("Listening on sock %d for live", sock->fd);
427
428 ret = sock->ops->bind(sock);
429 if (ret < 0) {
430 goto error;
431 }
432
433 ret = sock->ops->listen(sock, -1);
434 if (ret < 0) {
435 goto error;
436
437 }
438
439 return sock;
440
441error:
442 if (sock) {
443 lttcomm_destroy_sock(sock);
444 }
445 return NULL;
446}
447
448/*
449 * This thread manages the listening for new connections on the network
450 */
451static
452void *thread_listener(void *data)
453{
454 int i, ret, pollfd, err = -1;
d3e2ba59
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455 uint32_t revents, nb_fd;
456 struct lttng_poll_event events;
457 struct lttcomm_sock *live_control_sock;
458
459 DBG("[thread] Relay live listener started");
460
eea7556c
MD
461 health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_LISTENER);
462
463 health_code_update();
464
d3e2ba59
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465 live_control_sock = init_socket(live_uri);
466 if (!live_control_sock) {
467 goto error_sock_control;
468 }
469
fb4d42ab 470 /* Pass 2 as size here for the thread quit pipe and control sockets. */
d3e2ba59
JD
471 ret = create_thread_poll_set(&events, 2);
472 if (ret < 0) {
473 goto error_create_poll;
474 }
475
476 /* Add the control socket */
477 ret = lttng_poll_add(&events, live_control_sock->fd, LPOLLIN | LPOLLRDHUP);
478 if (ret < 0) {
479 goto error_poll_add;
480 }
481
3fd27398
MD
482 lttng_relay_notify_ready();
483
9b5e0863
MD
484 if (testpoint(relayd_thread_live_listener)) {
485 goto error_testpoint;
486 }
487
d3e2ba59 488 while (1) {
eea7556c
MD
489 health_code_update();
490
d3e2ba59
JD
491 DBG("Listener accepting live viewers connections");
492
493restart:
eea7556c 494 health_poll_entry();
d3e2ba59 495 ret = lttng_poll_wait(&events, -1);
eea7556c 496 health_poll_exit();
d3e2ba59
JD
497 if (ret < 0) {
498 /*
499 * Restart interrupted system call.
500 */
501 if (errno == EINTR) {
502 goto restart;
503 }
504 goto error;
505 }
506 nb_fd = ret;
507
508 DBG("Relay new viewer connection received");
509 for (i = 0; i < nb_fd; i++) {
eea7556c
MD
510 health_code_update();
511
d3e2ba59
JD
512 /* Fetch once the poll data */
513 revents = LTTNG_POLL_GETEV(&events, i);
514 pollfd = LTTNG_POLL_GETFD(&events, i);
515
516 /* Thread quit pipe has been closed. Killing thread. */
2a174661 517 ret = check_live_conn_pipe(pollfd, revents);
d3e2ba59
JD
518 if (ret) {
519 err = 0;
520 goto exit;
521 }
522
523 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
524 ERR("socket poll error");
525 goto error;
526 } else if (revents & LPOLLIN) {
527 /*
528 * Get allocated in this thread, enqueued to a global queue,
529 * dequeued and freed in the worker thread.
530 */
58eb9381
DG
531 int val = 1;
532 struct relay_connection *new_conn;
d3e2ba59
JD
533 struct lttcomm_sock *newsock;
534
58eb9381
DG
535 new_conn = connection_create();
536 if (!new_conn) {
d3e2ba59
JD
537 goto error;
538 }
539
d3e2ba59
JD
540 newsock = live_control_sock->ops->accept(live_control_sock);
541 if (!newsock) {
542 PERROR("accepting control sock");
58eb9381 543 connection_free(new_conn);
d3e2ba59
JD
544 goto error;
545 }
546 DBG("Relay viewer connection accepted socket %d", newsock->fd);
58eb9381 547
d3e2ba59 548 ret = setsockopt(newsock->fd, SOL_SOCKET, SO_REUSEADDR, &val,
58eb9381 549 sizeof(val));
d3e2ba59
JD
550 if (ret < 0) {
551 PERROR("setsockopt inet");
552 lttcomm_destroy_sock(newsock);
58eb9381 553 connection_free(new_conn);
d3e2ba59
JD
554 goto error;
555 }
58eb9381 556 new_conn->sock = newsock;
d3e2ba59 557
58eb9381
DG
558 /* Enqueue request for the dispatcher thread. */
559 cds_wfq_enqueue(&viewer_conn_queue.queue, &new_conn->qnode);
d3e2ba59
JD
560
561 /*
58eb9381
DG
562 * Wake the dispatch queue futex. Implicit memory barrier with
563 * the exchange in cds_wfq_enqueue.
d3e2ba59 564 */
58eb9381 565 futex_nto1_wake(&viewer_conn_queue.futex);
d3e2ba59
JD
566 }
567 }
568 }
569
570exit:
571error:
572error_poll_add:
9b5e0863 573error_testpoint:
d3e2ba59
JD
574 lttng_poll_clean(&events);
575error_create_poll:
576 if (live_control_sock->fd >= 0) {
577 ret = live_control_sock->ops->close(live_control_sock);
578 if (ret) {
579 PERROR("close");
580 }
581 }
582 lttcomm_destroy_sock(live_control_sock);
583error_sock_control:
584 if (err) {
eea7556c 585 health_error();
d3e2ba59
JD
586 DBG("Live viewer listener thread exited with error");
587 }
eea7556c 588 health_unregister(health_relayd);
d3e2ba59
JD
589 DBG("Live viewer listener thread cleanup complete");
590 stop_threads();
591 return NULL;
592}
593
594/*
595 * This thread manages the dispatching of the requests to worker threads
596 */
597static
598void *thread_dispatcher(void *data)
599{
6cd525e8
MD
600 int err = -1;
601 ssize_t ret;
d3e2ba59 602 struct cds_wfq_node *node;
58eb9381 603 struct relay_connection *conn = NULL;
d3e2ba59
JD
604
605 DBG("[thread] Live viewer relay dispatcher started");
606
eea7556c
MD
607 health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_DISPATCHER);
608
9b5e0863
MD
609 if (testpoint(relayd_thread_live_dispatcher)) {
610 goto error_testpoint;
611 }
612
eea7556c
MD
613 health_code_update();
614
d3e2ba59 615 while (!CMM_LOAD_SHARED(live_dispatch_thread_exit)) {
eea7556c
MD
616 health_code_update();
617
d3e2ba59 618 /* Atomically prepare the queue futex */
58eb9381 619 futex_nto1_prepare(&viewer_conn_queue.futex);
d3e2ba59
JD
620
621 do {
eea7556c
MD
622 health_code_update();
623
d3e2ba59 624 /* Dequeue commands */
58eb9381 625 node = cds_wfq_dequeue_blocking(&viewer_conn_queue.queue);
d3e2ba59
JD
626 if (node == NULL) {
627 DBG("Woken up but nothing in the live-viewer "
628 "relay command queue");
629 /* Continue thread execution */
630 break;
631 }
58eb9381 632 conn = caa_container_of(node, struct relay_connection, qnode);
d3e2ba59 633 DBG("Dispatching viewer request waiting on sock %d",
58eb9381 634 conn->sock->fd);
d3e2ba59
JD
635
636 /*
637 * Inform worker thread of the new request. This call is blocking
638 * so we can be assured that the data will be read at some point in
639 * time or wait to the end of the world :)
640 */
58eb9381
DG
641 ret = lttng_write(live_conn_pipe[1], &conn, sizeof(conn));
642 if (ret < 0) {
643 PERROR("write conn pipe");
644 connection_destroy(conn);
d3e2ba59
JD
645 goto error;
646 }
647 } while (node != NULL);
648
649 /* Futex wait on queue. Blocking call on futex() */
eea7556c 650 health_poll_entry();
58eb9381 651 futex_nto1_wait(&viewer_conn_queue.futex);
eea7556c 652 health_poll_exit();
d3e2ba59
JD
653 }
654
eea7556c
MD
655 /* Normal exit, no error */
656 err = 0;
657
d3e2ba59 658error:
9b5e0863 659error_testpoint:
eea7556c
MD
660 if (err) {
661 health_error();
662 ERR("Health error occurred in %s", __func__);
663 }
664 health_unregister(health_relayd);
d3e2ba59
JD
665 DBG("Live viewer dispatch thread dying");
666 stop_threads();
667 return NULL;
668}
669
670/*
671 * Establish connection with the viewer and check the versions.
672 *
673 * Return 0 on success or else negative value.
674 */
675static
58eb9381 676int viewer_connect(struct relay_connection *conn)
d3e2ba59
JD
677{
678 int ret;
679 struct lttng_viewer_connect reply, msg;
680
58eb9381 681 assert(conn);
d3e2ba59 682
58eb9381 683 conn->version_check_done = 1;
d3e2ba59 684
eea7556c
MD
685 health_code_update();
686
2f8f53af
DG
687 DBG("Viewer is establishing a connection to the relayd.");
688
58eb9381 689 ret = recv_request(conn->sock, &msg, sizeof(msg));
2f8f53af 690 if (ret < 0) {
d3e2ba59
JD
691 goto end;
692 }
693
eea7556c
MD
694 health_code_update();
695
d3e2ba59
JD
696 reply.major = RELAYD_VERSION_COMM_MAJOR;
697 reply.minor = RELAYD_VERSION_COMM_MINOR;
698
699 /* Major versions must be the same */
700 if (reply.major != be32toh(msg.major)) {
2f8f53af
DG
701 DBG("Incompatible major versions ([relayd] %u vs [client] %u)",
702 reply.major, be32toh(msg.major));
72180669 703 ret = -1;
d3e2ba59
JD
704 goto end;
705 }
706
58eb9381 707 conn->major = reply.major;
d3e2ba59
JD
708 /* We adapt to the lowest compatible version */
709 if (reply.minor <= be32toh(msg.minor)) {
58eb9381 710 conn->minor = reply.minor;
d3e2ba59 711 } else {
58eb9381 712 conn->minor = be32toh(msg.minor);
d3e2ba59
JD
713 }
714
c4e361a4 715 if (be32toh(msg.type) == LTTNG_VIEWER_CLIENT_COMMAND) {
58eb9381 716 conn->type = RELAY_VIEWER_COMMAND;
c4e361a4 717 } else if (be32toh(msg.type) == LTTNG_VIEWER_CLIENT_NOTIFICATION) {
58eb9381 718 conn->type = RELAY_VIEWER_NOTIFICATION;
d3e2ba59
JD
719 } else {
720 ERR("Unknown connection type : %u", be32toh(msg.type));
721 ret = -1;
722 goto end;
723 }
724
725 reply.major = htobe32(reply.major);
726 reply.minor = htobe32(reply.minor);
58eb9381 727 if (conn->type == RELAY_VIEWER_COMMAND) {
d3e2ba59
JD
728 reply.viewer_session_id = htobe64(++last_relay_viewer_session_id);
729 }
eea7556c
MD
730
731 health_code_update();
732
58eb9381 733 ret = send_response(conn->sock, &reply, sizeof(reply));
d3e2ba59 734 if (ret < 0) {
2f8f53af 735 goto end;
d3e2ba59
JD
736 }
737
eea7556c
MD
738 health_code_update();
739
58eb9381 740 DBG("Version check done using protocol %u.%u", conn->major, conn->minor);
d3e2ba59
JD
741 ret = 0;
742
743end:
744 return ret;
745}
746
747/*
748 * Send the viewer the list of current sessions.
749 *
750 * Return 0 on success or else a negative value.
751 */
752static
58eb9381 753int viewer_list_sessions(struct relay_connection *conn)
d3e2ba59
JD
754{
755 int ret;
756 struct lttng_viewer_list_sessions session_list;
757 unsigned long count;
758 long approx_before, approx_after;
d3e2ba59
JD
759 struct lttng_ht_iter iter;
760 struct lttng_viewer_session send_session;
761 struct relay_session *session;
762
763 DBG("List sessions received");
764
d3e2ba59 765 rcu_read_lock();
58eb9381
DG
766 cds_lfht_count_nodes(conn->sessions_ht->ht, &approx_before, &count,
767 &approx_after);
d3e2ba59
JD
768 session_list.sessions_count = htobe32(count);
769
eea7556c
MD
770 health_code_update();
771
58eb9381 772 ret = send_response(conn->sock, &session_list, sizeof(session_list));
d3e2ba59 773 if (ret < 0) {
d3e2ba59
JD
774 goto end_unlock;
775 }
776
eea7556c
MD
777 health_code_update();
778
58eb9381 779 cds_lfht_for_each_entry(conn->sessions_ht->ht, &iter.iter, session,
2f8f53af 780 session_n.node) {
eea7556c
MD
781 health_code_update();
782
d3e2ba59
JD
783 strncpy(send_session.session_name, session->session_name,
784 sizeof(send_session.session_name));
785 strncpy(send_session.hostname, session->hostname,
786 sizeof(send_session.hostname));
787 send_session.id = htobe64(session->id);
788 send_session.live_timer = htobe32(session->live_timer);
2a174661 789 send_session.clients = htobe32(session->viewer_refcount);
87b576ec 790 send_session.streams = htobe32(session->stream_count);
d3e2ba59 791
eea7556c
MD
792 health_code_update();
793
58eb9381 794 ret = send_response(conn->sock, &send_session, sizeof(send_session));
d3e2ba59 795 if (ret < 0) {
d3e2ba59
JD
796 goto end_unlock;
797 }
798 }
eea7556c
MD
799 health_code_update();
800
d3e2ba59
JD
801 rcu_read_unlock();
802 ret = 0;
803 goto end;
804
805end_unlock:
806 rcu_read_unlock();
807
808end:
d3e2ba59
JD
809 return ret;
810}
811
80e8027a
JD
812/*
813 * Send the viewer the list of current sessions.
814 */
815static
58eb9381 816int viewer_get_new_streams(struct relay_connection *conn)
80e8027a
JD
817{
818 int ret, send_streams = 0;
2f8f53af 819 uint32_t nb_created = 0, nb_unsent = 0, nb_streams = 0;
80e8027a
JD
820 struct lttng_viewer_new_streams_request request;
821 struct lttng_viewer_new_streams_response response;
80e8027a
JD
822 struct relay_session *session;
823
58eb9381 824 assert(conn);
80e8027a
JD
825
826 DBG("Get new streams received");
827
80e8027a
JD
828 health_code_update();
829
2f8f53af 830 /* Receive the request from the connected client. */
58eb9381 831 ret = recv_request(conn->sock, &request, sizeof(request));
2f8f53af 832 if (ret < 0) {
80e8027a
JD
833 goto error;
834 }
835
836 health_code_update();
837
838 rcu_read_lock();
58eb9381
DG
839 session = session_find_by_id(conn->sessions_ht,
840 be64toh(request.session_id));
2f8f53af 841 if (!session) {
80e8027a
JD
842 DBG("Relay session %" PRIu64 " not found",
843 be64toh(request.session_id));
c4e361a4 844 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR);
80e8027a
JD
845 goto send_reply;
846 }
847
58eb9381 848 if (conn->session_id == session->id) {
80e8027a
JD
849 /* We confirmed the viewer is asking for the same session. */
850 send_streams = 1;
c4e361a4 851 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_OK);
80e8027a
JD
852 } else {
853 send_streams = 0;
c4e361a4 854 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR);
80e8027a
JD
855 goto send_reply;
856 }
857
2f8f53af
DG
858 if (!send_streams) {
859 goto send_reply;
80e8027a 860 }
80e8027a 861
c4e361a4 862 ret = make_viewer_streams(session, LTTNG_VIEWER_SEEK_LAST, NULL, &nb_unsent,
2f8f53af
DG
863 &nb_created);
864 if (ret < 0) {
865 goto end_unlock;
866 }
867 /* Only send back the newly created streams with the unsent ones. */
868 nb_streams = nb_created + nb_unsent;
80e8027a
JD
869 response.streams_count = htobe32(nb_streams);
870
871send_reply:
872 health_code_update();
58eb9381 873 ret = send_response(conn->sock, &response, sizeof(response));
80e8027a 874 if (ret < 0) {
80e8027a
JD
875 goto end_unlock;
876 }
877 health_code_update();
878
879 /*
880 * Unknown or empty session, just return gracefully, the viewer knows what
881 * is happening.
882 */
883 if (!send_streams || !nb_streams) {
884 ret = 0;
885 goto end_unlock;
886 }
887
2f8f53af
DG
888 /*
889 * Send stream and *DON'T* ignore the sent flag so every viewer streams
890 * that were not sent from that point will be sent to the viewer.
891 */
58eb9381 892 ret = send_viewer_streams(conn->sock, session, 0);
2f8f53af
DG
893 if (ret < 0) {
894 goto end_unlock;
80e8027a
JD
895 }
896
80e8027a
JD
897end_unlock:
898 rcu_read_unlock();
80e8027a
JD
899error:
900 return ret;
901}
902
d3e2ba59
JD
903/*
904 * Send the viewer the list of current sessions.
905 */
906static
58eb9381 907int viewer_attach_session(struct relay_connection *conn)
d3e2ba59 908{
2f8f53af
DG
909 int send_streams = 0;
910 ssize_t ret;
80e8027a 911 uint32_t nb_streams = 0;
2f8f53af 912 enum lttng_viewer_seek seek_type;
d3e2ba59
JD
913 struct lttng_viewer_attach_session_request request;
914 struct lttng_viewer_attach_session_response response;
d3e2ba59
JD
915 struct relay_session *session;
916
58eb9381 917 assert(conn);
d3e2ba59 918
eea7556c
MD
919 health_code_update();
920
2f8f53af 921 /* Receive the request from the connected client. */
58eb9381 922 ret = recv_request(conn->sock, &request, sizeof(request));
2f8f53af 923 if (ret < 0) {
d3e2ba59
JD
924 goto error;
925 }
926
eea7556c
MD
927 health_code_update();
928
d3e2ba59 929 rcu_read_lock();
58eb9381
DG
930 session = session_find_by_id(conn->sessions_ht,
931 be64toh(request.session_id));
2f8f53af 932 if (!session) {
d3e2ba59
JD
933 DBG("Relay session %" PRIu64 " not found",
934 be64toh(request.session_id));
c4e361a4 935 response.status = htobe32(LTTNG_VIEWER_ATTACH_UNK);
d3e2ba59
JD
936 goto send_reply;
937 }
2a174661
DG
938 session_viewer_attach(session);
939 DBG("Attach session ID %" PRIu64 " received", be64toh(request.session_id));
d3e2ba59 940
2a174661 941 if (uatomic_read(&session->viewer_refcount) > 1) {
d3e2ba59 942 DBG("Already a viewer attached");
c4e361a4 943 response.status = htobe32(LTTNG_VIEWER_ATTACH_ALREADY);
2a174661 944 session_viewer_detach(session);
d3e2ba59
JD
945 goto send_reply;
946 } else if (session->live_timer == 0) {
947 DBG("Not live session");
c4e361a4 948 response.status = htobe32(LTTNG_VIEWER_ATTACH_NOT_LIVE);
d3e2ba59
JD
949 goto send_reply;
950 } else {
d3e2ba59 951 send_streams = 1;
c4e361a4 952 response.status = htobe32(LTTNG_VIEWER_ATTACH_OK);
58eb9381
DG
953 conn->session_id = session->id;
954 conn->session = session;
d3e2ba59
JD
955 }
956
957 switch (be32toh(request.seek)) {
c4e361a4
JD
958 case LTTNG_VIEWER_SEEK_BEGINNING:
959 case LTTNG_VIEWER_SEEK_LAST:
2f8f53af 960 seek_type = be32toh(request.seek);
d3e2ba59
JD
961 break;
962 default:
963 ERR("Wrong seek parameter");
c4e361a4 964 response.status = htobe32(LTTNG_VIEWER_ATTACH_SEEK_ERR);
d3e2ba59
JD
965 send_streams = 0;
966 goto send_reply;
967 }
968
2f8f53af
DG
969 if (!send_streams) {
970 goto send_reply;
971 }
a4baae1b 972
2f8f53af
DG
973 ret = make_viewer_streams(session, seek_type, &nb_streams, NULL, NULL);
974 if (ret < 0) {
975 goto end_unlock;
d3e2ba59 976 }
2f8f53af 977 response.streams_count = htobe32(nb_streams);
d3e2ba59
JD
978
979send_reply:
eea7556c 980 health_code_update();
58eb9381 981 ret = send_response(conn->sock, &response, sizeof(response));
d3e2ba59 982 if (ret < 0) {
d3e2ba59
JD
983 goto end_unlock;
984 }
eea7556c 985 health_code_update();
d3e2ba59
JD
986
987 /*
157df586 988 * Unknown or empty session, just return gracefully, the viewer knows what
d3e2ba59
JD
989 * is happening.
990 */
157df586 991 if (!send_streams || !nb_streams) {
d3e2ba59
JD
992 ret = 0;
993 goto end_unlock;
994 }
995
2f8f53af 996 /* Send stream and ignore the sent flag. */
58eb9381 997 ret = send_viewer_streams(conn->sock, session, 1);
2f8f53af
DG
998 if (ret < 0) {
999 goto end_unlock;
d3e2ba59 1000 }
d3e2ba59
JD
1001
1002end_unlock:
1003 rcu_read_unlock();
4a9daf17
JD
1004error:
1005 return ret;
1006}
1007
d3e2ba59
JD
1008/*
1009 * Send the next index for a stream.
1010 *
1011 * Return 0 on success or else a negative value.
1012 */
1013static
58eb9381 1014int viewer_get_next_index(struct relay_connection *conn)
d3e2ba59
JD
1015{
1016 int ret;
1017 struct lttng_viewer_get_next_index request_index;
1018 struct lttng_viewer_index viewer_index;
50adc264 1019 struct ctf_packet_index packet_index;
d3e2ba59
JD
1020 struct relay_viewer_stream *vstream;
1021 struct relay_stream *rstream;
2a174661
DG
1022 struct ctf_trace *ctf_trace;
1023 struct relay_session *session;
d3e2ba59 1024
58eb9381 1025 assert(conn);
d3e2ba59
JD
1026
1027 DBG("Viewer get next index");
1028
eea7556c 1029 health_code_update();
2f8f53af 1030
58eb9381 1031 ret = recv_request(conn->sock, &request_index, sizeof(request_index));
2f8f53af 1032 if (ret < 0) {
d3e2ba59
JD
1033 goto end;
1034 }
eea7556c 1035 health_code_update();
d3e2ba59
JD
1036
1037 rcu_read_lock();
58eb9381 1038 session = session_find_by_id(conn->sessions_ht, conn->session_id);
2a174661
DG
1039 if (!session) {
1040 ret = -1;
1041 goto end_unlock;
1042 }
1043
2f8f53af 1044 vstream = viewer_stream_find_by_id(be64toh(request_index.stream_id));
d3e2ba59
JD
1045 if (!vstream) {
1046 ret = -1;
1047 goto end_unlock;
1048 }
1049
2a174661
DG
1050 ctf_trace = ctf_trace_find_by_path(session->ctf_traces_ht, vstream->path_name);
1051 assert(ctf_trace);
1052
d3e2ba59
JD
1053 memset(&viewer_index, 0, sizeof(viewer_index));
1054
1055 /*
1056 * The viewer should not ask for index on metadata stream.
1057 */
1058 if (vstream->metadata_flag) {
c4e361a4 1059 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_HUP);
d3e2ba59
JD
1060 goto send_reply;
1061 }
1062
1063 /* First time, we open the index file */
1064 if (vstream->index_read_fd < 0) {
2f8f53af
DG
1065 ret = index_open(vstream->path_name, vstream->channel_name,
1066 vstream->tracefile_count, vstream->tracefile_count_current);
0e6830aa 1067 if (ret == -ENOENT) {
d3e2ba59
JD
1068 /*
1069 * The index is created only when the first data packet arrives, it
1070 * might not be ready at the beginning of the session
1071 */
c4e361a4 1072 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
d3e2ba59
JD
1073 goto send_reply;
1074 } else if (ret < 0) {
c4e361a4 1075 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
d3e2ba59
JD
1076 goto send_reply;
1077 }
2f8f53af 1078 vstream->index_read_fd = ret;
d3e2ba59
JD
1079 }
1080
2a174661
DG
1081 rstream = stream_find_by_id(relay_streams_ht, vstream->stream_handle);
1082 assert(rstream);
1083
1084 if (!rstream->close_flag) {
6b6b9a5a
JD
1085 if (vstream->abort_flag) {
1086 /* Rotate on abort (overwrite). */
1087 DBG("Viewer rotate because of overwrite");
2f8f53af 1088 ret = viewer_stream_rotate(vstream, rstream);
6b6b9a5a
JD
1089 if (ret < 0) {
1090 goto end_unlock;
a020f610 1091 } else if (ret == 1) {
c4e361a4 1092 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_HUP);
2f8f53af 1093 viewer_stream_delete(vstream);
2a174661 1094 viewer_stream_destroy(ctf_trace, vstream);
a020f610 1095 goto send_reply;
6b6b9a5a 1096 }
2a174661 1097 /* ret == 0 means successful so we continue. */
6b6b9a5a 1098 }
2a174661 1099
6b6b9a5a 1100 pthread_mutex_lock(&rstream->viewer_stream_rotation_lock);
cef0f7d5
JD
1101 if (rstream->tracefile_count_current == vstream->tracefile_count_current) {
1102 if (rstream->beacon_ts_end != -1ULL &&
1103 vstream->last_sent_index == rstream->total_index_received) {
c4e361a4 1104 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_INACTIVE);
cef0f7d5
JD
1105 viewer_index.timestamp_end = htobe64(rstream->beacon_ts_end);
1106 pthread_mutex_unlock(&rstream->viewer_stream_rotation_lock);
1107 goto send_reply;
cef0f7d5
JD
1108 } else if (rstream->total_index_received <= vstream->last_sent_index
1109 && !vstream->close_write_flag) {
2a174661
DG
1110 /*
1111 * Reader and writer are working in the same tracefile, so we care
1112 * about the number of index received and sent. Otherwise, we read
1113 * up to EOF.
1114 */
cef0f7d5
JD
1115 pthread_mutex_unlock(&rstream->viewer_stream_rotation_lock);
1116 /* No new index to send, retry later. */
c4e361a4 1117 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
cef0f7d5
JD
1118 goto send_reply;
1119 }
d3e2ba59 1120 }
6b6b9a5a 1121 pthread_mutex_unlock(&rstream->viewer_stream_rotation_lock);
2a174661 1122 } else if (rstream->close_flag && vstream->close_write_flag &&
d3e2ba59 1123 vstream->total_index_received == vstream->last_sent_index) {
6b6b9a5a 1124 /* Last index sent and current tracefile closed in write */
c4e361a4 1125 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_HUP);
2f8f53af 1126 viewer_stream_delete(vstream);
2a174661 1127 viewer_stream_destroy(ctf_trace, vstream);
d3e2ba59 1128 goto send_reply;
6b6b9a5a
JD
1129 } else {
1130 vstream->close_write_flag = 1;
d3e2ba59
JD
1131 }
1132
2a174661
DG
1133 if (!ctf_trace->metadata_received ||
1134 ctf_trace->metadata_received > ctf_trace->metadata_sent) {
d3e2ba59
JD
1135 viewer_index.flags |= LTTNG_VIEWER_FLAG_NEW_METADATA;
1136 }
1137
58eb9381 1138 ret = check_new_streams(vstream->session_id, conn->sessions_ht);
4a9daf17
JD
1139 if (ret < 0) {
1140 goto end_unlock;
1141 } else if (ret == 1) {
1142 viewer_index.flags |= LTTNG_VIEWER_FLAG_NEW_STREAM;
1143 }
1144
cef0f7d5
JD
1145 pthread_mutex_lock(&vstream->overwrite_lock);
1146 if (vstream->abort_flag) {
1147 /*
2a174661 1148 * The file is being overwritten by the writer, we cannot * use it.
cef0f7d5 1149 */
c4e361a4 1150 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
cef0f7d5 1151 pthread_mutex_unlock(&vstream->overwrite_lock);
2f8f53af 1152 ret = viewer_stream_rotate(vstream, rstream);
cef0f7d5
JD
1153 if (ret < 0) {
1154 goto end_unlock;
a020f610 1155 } else if (ret == 1) {
c4e361a4 1156 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_HUP);
2f8f53af 1157 viewer_stream_delete(vstream);
2a174661 1158 viewer_stream_destroy(ctf_trace, vstream);
a020f610 1159 goto send_reply;
cef0f7d5
JD
1160 }
1161 goto send_reply;
1162 }
2f8f53af 1163
6cd525e8
MD
1164 ret = lttng_read(vstream->index_read_fd, &packet_index,
1165 sizeof(packet_index));
cef0f7d5 1166 pthread_mutex_unlock(&vstream->overwrite_lock);
d3e2ba59 1167 if (ret < sizeof(packet_index)) {
6b6b9a5a
JD
1168 /*
1169 * The tracefile is closed in write, so we read up to EOF.
1170 */
1171 if (vstream->close_write_flag == 1) {
c4e361a4 1172 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
6b6b9a5a 1173 /* Rotate on normal EOF */
2f8f53af 1174 ret = viewer_stream_rotate(vstream, rstream);
6b6b9a5a
JD
1175 if (ret < 0) {
1176 goto end_unlock;
a020f610 1177 } else if (ret == 1) {
c4e361a4 1178 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_HUP);
2f8f53af 1179 viewer_stream_delete(vstream);
2a174661 1180 viewer_stream_destroy(ctf_trace, vstream);
a020f610 1181 goto send_reply;
6b6b9a5a
JD
1182 }
1183 } else {
2f8f53af 1184 PERROR("Relay reading index file %d", vstream->index_read_fd);
c4e361a4 1185 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
6b6b9a5a
JD
1186 }
1187 goto send_reply;
d3e2ba59 1188 } else {
c4e361a4 1189 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_OK);
d3e2ba59
JD
1190 vstream->last_sent_index++;
1191 }
1192
1193 /*
1194 * Indexes are stored in big endian, no need to switch before sending.
1195 */
1196 viewer_index.offset = packet_index.offset;
1197 viewer_index.packet_size = packet_index.packet_size;
1198 viewer_index.content_size = packet_index.content_size;
1199 viewer_index.timestamp_begin = packet_index.timestamp_begin;
1200 viewer_index.timestamp_end = packet_index.timestamp_end;
1201 viewer_index.events_discarded = packet_index.events_discarded;
1202 viewer_index.stream_id = packet_index.stream_id;
1203
1204send_reply:
1205 viewer_index.flags = htobe32(viewer_index.flags);
eea7556c 1206 health_code_update();
2f8f53af 1207
58eb9381 1208 ret = send_response(conn->sock, &viewer_index, sizeof(viewer_index));
d3e2ba59 1209 if (ret < 0) {
d3e2ba59
JD
1210 goto end_unlock;
1211 }
eea7556c 1212 health_code_update();
d3e2ba59 1213
2f8f53af 1214 DBG("Index %" PRIu64 " for stream %" PRIu64 " sent",
d3e2ba59
JD
1215 vstream->last_sent_index, vstream->stream_handle);
1216
1217end_unlock:
1218 rcu_read_unlock();
1219
d3e2ba59
JD
1220end:
1221 return ret;
1222}
1223
1224/*
1225 * Send the next index for a stream
1226 *
1227 * Return 0 on success or else a negative value.
1228 */
1229static
58eb9381 1230int viewer_get_packet(struct relay_connection *conn)
d3e2ba59
JD
1231{
1232 int ret, send_data = 0;
1233 char *data = NULL;
1234 uint32_t len = 0;
1235 ssize_t read_len;
1236 struct lttng_viewer_get_packet get_packet_info;
1237 struct lttng_viewer_trace_packet reply;
1238 struct relay_viewer_stream *stream;
2a174661 1239 struct ctf_trace *ctf_trace;
d3e2ba59 1240
58eb9381 1241 assert(conn);
d3e2ba59
JD
1242
1243 DBG2("Relay get data packet");
1244
eea7556c 1245 health_code_update();
2f8f53af 1246
58eb9381 1247 ret = recv_request(conn->sock, &get_packet_info, sizeof(get_packet_info));
2f8f53af 1248 if (ret < 0) {
d3e2ba59
JD
1249 goto end;
1250 }
eea7556c 1251 health_code_update();
d3e2ba59 1252
0233a6a5
DG
1253 /* From this point on, the error label can be reached. */
1254 memset(&reply, 0, sizeof(reply));
1255
d3e2ba59 1256 rcu_read_lock();
2f8f53af 1257 stream = viewer_stream_find_by_id(be64toh(get_packet_info.stream_id));
d3e2ba59
JD
1258 if (!stream) {
1259 goto error;
1260 }
2a174661 1261
58eb9381 1262 ctf_trace = ctf_trace_find_by_path(conn->session->ctf_traces_ht,
2a174661
DG
1263 stream->path_name);
1264 assert(ctf_trace);
d3e2ba59
JD
1265
1266 /*
1267 * First time we read this stream, we need open the tracefile, we should
1268 * only arrive here if an index has already been sent to the viewer, so the
1269 * tracefile must exist, if it does not it is a fatal error.
1270 */
1271 if (stream->read_fd < 0) {
1272 char fullpath[PATH_MAX];
1273
6b6b9a5a
JD
1274 if (stream->tracefile_count > 0) {
1275 ret = snprintf(fullpath, PATH_MAX, "%s/%s_%" PRIu64, stream->path_name,
1276 stream->channel_name,
1277 stream->tracefile_count_current);
1278 } else {
1279 ret = snprintf(fullpath, PATH_MAX, "%s/%s", stream->path_name,
1280 stream->channel_name);
1281 }
d3e2ba59
JD
1282 if (ret < 0) {
1283 goto error;
1284 }
1285 ret = open(fullpath, O_RDONLY);
1286 if (ret < 0) {
1287 PERROR("Relay opening trace file");
1288 goto error;
1289 }
1290 stream->read_fd = ret;
1291 }
1292
2a174661
DG
1293 if (!ctf_trace->metadata_received ||
1294 ctf_trace->metadata_received > ctf_trace->metadata_sent) {
c4e361a4 1295 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_ERR);
d3e2ba59 1296 reply.flags |= LTTNG_VIEWER_FLAG_NEW_METADATA;
d3e2ba59
JD
1297 goto send_reply;
1298 }
1299
58eb9381 1300 ret = check_new_streams(stream->session_id, conn->sessions_ht);
4a9daf17
JD
1301 if (ret < 0) {
1302 goto end_unlock;
1303 } else if (ret == 1) {
c4e361a4 1304 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_ERR);
4a9daf17
JD
1305 reply.flags |= LTTNG_VIEWER_FLAG_NEW_STREAM;
1306 goto send_reply;
1307 }
1308
d3e2ba59
JD
1309 len = be32toh(get_packet_info.len);
1310 data = zmalloc(len);
1311 if (!data) {
1312 PERROR("relay data zmalloc");
1313 goto error;
1314 }
1315
1316 ret = lseek(stream->read_fd, be64toh(get_packet_info.offset), SEEK_SET);
1317 if (ret < 0) {
6b6b9a5a
JD
1318 /*
1319 * If the read fd was closed by the streaming side, the
1320 * abort_flag will be set to 1, otherwise it is an error.
1321 */
1322 if (stream->abort_flag == 0) {
1323 PERROR("lseek");
1324 goto error;
1325 }
c4e361a4 1326 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_EOF);
6b6b9a5a 1327 goto send_reply;
d3e2ba59 1328 }
6cd525e8
MD
1329 read_len = lttng_read(stream->read_fd, data, len);
1330 if (read_len < len) {
6b6b9a5a
JD
1331 /*
1332 * If the read fd was closed by the streaming side, the
1333 * abort_flag will be set to 1, otherwise it is an error.
1334 */
1335 if (stream->abort_flag == 0) {
1336 PERROR("Relay reading trace file, fd: %d, offset: %" PRIu64,
1337 stream->read_fd,
1338 be64toh(get_packet_info.offset));
1339 goto error;
1340 } else {
c4e361a4 1341 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_EOF);
6b6b9a5a
JD
1342 goto send_reply;
1343 }
d3e2ba59 1344 }
c4e361a4 1345 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_OK);
d3e2ba59
JD
1346 reply.len = htobe32(len);
1347 send_data = 1;
1348 goto send_reply;
1349
1350error:
c4e361a4 1351 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_ERR);
d3e2ba59
JD
1352
1353send_reply:
1354 reply.flags = htobe32(reply.flags);
eea7556c
MD
1355
1356 health_code_update();
2f8f53af 1357
58eb9381 1358 ret = send_response(conn->sock, &reply, sizeof(reply));
d3e2ba59 1359 if (ret < 0) {
d3e2ba59
JD
1360 goto end_unlock;
1361 }
eea7556c 1362 health_code_update();
d3e2ba59
JD
1363
1364 if (send_data) {
eea7556c 1365 health_code_update();
58eb9381 1366 ret = send_response(conn->sock, data, len);
d3e2ba59 1367 if (ret < 0) {
d3e2ba59
JD
1368 goto end_unlock;
1369 }
eea7556c 1370 health_code_update();
d3e2ba59
JD
1371 }
1372
1373 DBG("Sent %u bytes for stream %" PRIu64, len,
1374 be64toh(get_packet_info.stream_id));
1375
1376end_unlock:
1377 free(data);
1378 rcu_read_unlock();
1379
1380end:
1381 return ret;
1382}
1383
1384/*
1385 * Send the session's metadata
1386 *
1387 * Return 0 on success else a negative value.
1388 */
1389static
58eb9381 1390int viewer_get_metadata(struct relay_connection *conn)
d3e2ba59
JD
1391{
1392 int ret = 0;
1393 ssize_t read_len;
1394 uint64_t len = 0;
1395 char *data = NULL;
1396 struct lttng_viewer_get_metadata request;
1397 struct lttng_viewer_metadata_packet reply;
1398 struct relay_viewer_stream *stream;
2a174661 1399 struct ctf_trace *ctf_trace;
d3e2ba59 1400
58eb9381 1401 assert(conn);
d3e2ba59
JD
1402
1403 DBG("Relay get metadata");
1404
eea7556c 1405 health_code_update();
2f8f53af 1406
58eb9381 1407 ret = recv_request(conn->sock, &request, sizeof(request));
2f8f53af 1408 if (ret < 0) {
d3e2ba59
JD
1409 goto end;
1410 }
eea7556c 1411 health_code_update();
d3e2ba59
JD
1412
1413 rcu_read_lock();
2f8f53af 1414 stream = viewer_stream_find_by_id(be64toh(request.stream_id));
d3e2ba59
JD
1415 if (!stream || !stream->metadata_flag) {
1416 ERR("Invalid metadata stream");
1417 goto error;
1418 }
d3e2ba59 1419
58eb9381 1420 ctf_trace = ctf_trace_find_by_path(conn->session->ctf_traces_ht,
2a174661
DG
1421 stream->path_name);
1422 assert(ctf_trace);
1423 assert(ctf_trace->metadata_sent <= ctf_trace->metadata_received);
1424
1425 len = ctf_trace->metadata_received - ctf_trace->metadata_sent;
d3e2ba59 1426 if (len == 0) {
c4e361a4 1427 reply.status = htobe32(LTTNG_VIEWER_NO_NEW_METADATA);
d3e2ba59
JD
1428 goto send_reply;
1429 }
1430
1431 /* first time, we open the metadata file */
1432 if (stream->read_fd < 0) {
1433 char fullpath[PATH_MAX];
1434
1435 ret = snprintf(fullpath, PATH_MAX, "%s/%s", stream->path_name,
1436 stream->channel_name);
1437 if (ret < 0) {
1438 goto error;
1439 }
1440 ret = open(fullpath, O_RDONLY);
1441 if (ret < 0) {
1442 PERROR("Relay opening metadata file");
1443 goto error;
1444 }
1445 stream->read_fd = ret;
1446 }
1447
1448 reply.len = htobe64(len);
1449 data = zmalloc(len);
1450 if (!data) {
1451 PERROR("viewer metadata zmalloc");
1452 goto error;
1453 }
1454
6cd525e8
MD
1455 read_len = lttng_read(stream->read_fd, data, len);
1456 if (read_len < len) {
d3e2ba59
JD
1457 PERROR("Relay reading metadata file");
1458 goto error;
1459 }
2a174661 1460 ctf_trace->metadata_sent += read_len;
c4e361a4 1461 reply.status = htobe32(LTTNG_VIEWER_METADATA_OK);
d3e2ba59
JD
1462 goto send_reply;
1463
1464error:
c4e361a4 1465 reply.status = htobe32(LTTNG_VIEWER_METADATA_ERR);
d3e2ba59
JD
1466
1467send_reply:
eea7556c 1468 health_code_update();
58eb9381 1469 ret = send_response(conn->sock, &reply, sizeof(reply));
d3e2ba59 1470 if (ret < 0) {
d3e2ba59
JD
1471 goto end_unlock;
1472 }
eea7556c 1473 health_code_update();
d3e2ba59
JD
1474
1475 if (len > 0) {
58eb9381 1476 ret = send_response(conn->sock, data, len);
d3e2ba59 1477 if (ret < 0) {
d3e2ba59
JD
1478 goto end_unlock;
1479 }
1480 }
1481
1482 DBG("Sent %" PRIu64 " bytes of metadata for stream %" PRIu64, len,
1483 be64toh(request.stream_id));
1484
1485 DBG("Metadata sent");
1486
1487end_unlock:
1488 free(data);
1489 rcu_read_unlock();
1490end:
1491 return ret;
1492}
1493
1494/*
1495 * live_relay_unknown_command: send -1 if received unknown command
1496 */
1497static
58eb9381 1498void live_relay_unknown_command(struct relay_connection *conn)
d3e2ba59
JD
1499{
1500 struct lttcomm_relayd_generic_reply reply;
d3e2ba59
JD
1501
1502 reply.ret_code = htobe32(LTTNG_ERR_UNK);
58eb9381 1503 (void) send_response(conn->sock, &reply, sizeof(reply));
d3e2ba59
JD
1504}
1505
1506/*
1507 * Process the commands received on the control socket
1508 */
1509static
1510int process_control(struct lttng_viewer_cmd *recv_hdr,
58eb9381 1511 struct relay_connection *conn)
d3e2ba59
JD
1512{
1513 int ret = 0;
2f8f53af
DG
1514 uint32_t msg_value;
1515
1516 assert(recv_hdr);
58eb9381 1517 assert(conn);
2f8f53af
DG
1518
1519 msg_value = be32toh(recv_hdr->cmd);
1520
1521 /*
1522 * Make sure we've done the version check before any command other then a
1523 * new client connection.
1524 */
c4e361a4 1525 if (msg_value != LTTNG_VIEWER_CONNECT && !conn->version_check_done) {
58eb9381 1526 ERR("Viewer conn value %" PRIu32 " before version check", msg_value);
2f8f53af
DG
1527 ret = -1;
1528 goto end;
1529 }
d3e2ba59 1530
2f8f53af 1531 switch (msg_value) {
c4e361a4 1532 case LTTNG_VIEWER_CONNECT:
58eb9381 1533 ret = viewer_connect(conn);
d3e2ba59 1534 break;
c4e361a4 1535 case LTTNG_VIEWER_LIST_SESSIONS:
58eb9381 1536 ret = viewer_list_sessions(conn);
d3e2ba59 1537 break;
c4e361a4 1538 case LTTNG_VIEWER_ATTACH_SESSION:
58eb9381 1539 ret = viewer_attach_session(conn);
d3e2ba59 1540 break;
c4e361a4 1541 case LTTNG_VIEWER_GET_NEXT_INDEX:
58eb9381 1542 ret = viewer_get_next_index(conn);
d3e2ba59 1543 break;
c4e361a4 1544 case LTTNG_VIEWER_GET_PACKET:
58eb9381 1545 ret = viewer_get_packet(conn);
d3e2ba59 1546 break;
c4e361a4 1547 case LTTNG_VIEWER_GET_METADATA:
58eb9381 1548 ret = viewer_get_metadata(conn);
d3e2ba59 1549 break;
c4e361a4 1550 case LTTNG_VIEWER_GET_NEW_STREAMS:
58eb9381 1551 ret = viewer_get_new_streams(conn);
80e8027a 1552 break;
d3e2ba59
JD
1553 default:
1554 ERR("Received unknown viewer command (%u)", be32toh(recv_hdr->cmd));
58eb9381 1555 live_relay_unknown_command(conn);
d3e2ba59
JD
1556 ret = -1;
1557 goto end;
1558 }
1559
1560end:
1561 return ret;
1562}
1563
1564static
58eb9381 1565void cleanup_connection_pollfd(struct lttng_poll_event *events, int pollfd)
d3e2ba59
JD
1566{
1567 int ret;
1568
1569 assert(events);
1570
58eb9381 1571 (void) lttng_poll_del(events, pollfd);
d3e2ba59
JD
1572
1573 ret = close(pollfd);
1574 if (ret < 0) {
1575 ERR("Closing pollfd %d", pollfd);
1576 }
1577}
1578
157df586
JD
1579/*
1580 * Delete all streams for a specific session ID.
1581 */
2a174661 1582static void destroy_viewer_streams_by_session(struct relay_session *session)
d3e2ba59 1583{
d3e2ba59 1584 struct relay_viewer_stream *stream;
d3e2ba59
JD
1585 struct lttng_ht_iter iter;
1586
2a174661
DG
1587 assert(session);
1588
d3e2ba59 1589 rcu_read_lock();
157df586
JD
1590 cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter, stream,
1591 stream_n.node) {
2a174661 1592 struct ctf_trace *ctf_trace;
eea7556c 1593
2a174661
DG
1594 health_code_update();
1595 if (stream->session_id != session->id) {
d3e2ba59
JD
1596 continue;
1597 }
1598
2a174661
DG
1599 ctf_trace = ctf_trace_find_by_path(session->ctf_traces_ht,
1600 stream->path_name);
1601 assert(ctf_trace);
1602
2f8f53af 1603 viewer_stream_delete(stream);
157df586
JD
1604
1605 if (stream->metadata_flag) {
2a174661
DG
1606 ctf_trace->metadata_sent = 0;
1607 ctf_trace->viewer_metadata_stream = NULL;
d3e2ba59 1608 }
2a174661
DG
1609
1610 viewer_stream_destroy(ctf_trace, stream);
d3e2ba59
JD
1611 }
1612 rcu_read_unlock();
1613}
1614
2a174661
DG
1615static void try_destroy_streams(struct relay_session *session)
1616{
1617 struct ctf_trace *ctf_trace;
1618 struct lttng_ht_iter iter;
1619
1620 assert(session);
1621
1622 cds_lfht_for_each_entry(session->ctf_traces_ht->ht, &iter.iter, ctf_trace,
1623 node.node) {
1624 /* Attempt to destroy the ctf trace of that session. */
1625 ctf_trace_try_destroy(session, ctf_trace);
1626 }
1627}
1628
d3e2ba59 1629/*
58eb9381 1630 * Delete and destroy a connection.
d3e2ba59
JD
1631 *
1632 * RCU read side lock MUST be acquired.
1633 */
58eb9381
DG
1634static void destroy_connection(struct lttng_ht *relay_connections_ht,
1635 struct relay_connection *conn)
d3e2ba59 1636{
2a174661 1637 struct relay_session *session;
d3e2ba59
JD
1638
1639 assert(relay_connections_ht);
58eb9381 1640 assert(conn);
d3e2ba59 1641
58eb9381 1642 DBG("Cleaning connection of session ID %" PRIu64, conn->session_id);
157df586 1643
58eb9381 1644 connection_delete(relay_connections_ht, conn);
d3e2ba59 1645
58eb9381
DG
1646 rcu_read_lock();
1647 session = session_find_by_id(conn->sessions_ht, conn->session_id);
2a174661
DG
1648 if (session) {
1649 /*
1650 * Very important that this is done before destroying the session so we
1651 * can put back every viewer stream reference from the ctf_trace.
1652 */
1653 destroy_viewer_streams_by_session(session);
1654 try_destroy_streams(session);
58eb9381 1655 session_viewer_try_destroy(conn->sessions_ht, session);
2a174661
DG
1656 }
1657 rcu_read_unlock();
d3e2ba59 1658
58eb9381 1659 connection_destroy(conn);
d3e2ba59
JD
1660}
1661
1662/*
1663 * This thread does the actual work
1664 */
1665static
1666void *thread_worker(void *data)
1667{
1668 int ret, err = -1;
1669 uint32_t nb_fd;
58eb9381 1670 struct relay_connection *conn;
d3e2ba59
JD
1671 struct lttng_poll_event events;
1672 struct lttng_ht *relay_connections_ht;
d3e2ba59
JD
1673 struct lttng_ht_iter iter;
1674 struct lttng_viewer_cmd recv_hdr;
1675 struct relay_local_data *relay_ctx = (struct relay_local_data *) data;
1676 struct lttng_ht *sessions_ht = relay_ctx->sessions_ht;
d3e2ba59
JD
1677
1678 DBG("[thread] Live viewer relay worker started");
1679
1680 rcu_register_thread();
1681
eea7556c
MD
1682 health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_WORKER);
1683
9b5e0863
MD
1684 if (testpoint(relayd_thread_live_worker)) {
1685 goto error_testpoint;
1686 }
1687
d3e2ba59
JD
1688 /* table of connections indexed on socket */
1689 relay_connections_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1690 if (!relay_connections_ht) {
1691 goto relay_connections_ht_error;
1692 }
1693
1694 ret = create_thread_poll_set(&events, 2);
1695 if (ret < 0) {
1696 goto error_poll_create;
1697 }
1698
58eb9381 1699 ret = lttng_poll_add(&events, live_conn_pipe[0], LPOLLIN | LPOLLRDHUP);
d3e2ba59
JD
1700 if (ret < 0) {
1701 goto error;
1702 }
1703
1704restart:
1705 while (1) {
1706 int i;
1707
eea7556c
MD
1708 health_code_update();
1709
d3e2ba59
JD
1710 /* Infinite blocking call, waiting for transmission */
1711 DBG3("Relayd live viewer worker thread polling...");
eea7556c 1712 health_poll_entry();
d3e2ba59 1713 ret = lttng_poll_wait(&events, -1);
eea7556c 1714 health_poll_exit();
d3e2ba59
JD
1715 if (ret < 0) {
1716 /*
1717 * Restart interrupted system call.
1718 */
1719 if (errno == EINTR) {
1720 goto restart;
1721 }
1722 goto error;
1723 }
1724
1725 nb_fd = ret;
1726
1727 /*
1728 * Process control. The control connection is prioritised so we don't
1729 * starve it with high throughput tracing data on the data
1730 * connection.
1731 */
1732 for (i = 0; i < nb_fd; i++) {
1733 /* Fetch once the poll data */
1734 uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1735 int pollfd = LTTNG_POLL_GETFD(&events, i);
1736
eea7556c
MD
1737 health_code_update();
1738
d3e2ba59 1739 /* Thread quit pipe has been closed. Killing thread. */
2a174661 1740 ret = check_live_conn_pipe(pollfd, revents);
d3e2ba59
JD
1741 if (ret) {
1742 err = 0;
1743 goto exit;
1744 }
1745
58eb9381
DG
1746 /* Inspect the relay conn pipe for new connection */
1747 if (pollfd == live_conn_pipe[0]) {
d3e2ba59
JD
1748 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1749 ERR("Relay live pipe error");
1750 goto error;
1751 } else if (revents & LPOLLIN) {
58eb9381 1752 ret = lttng_read(live_conn_pipe[0], &conn, sizeof(conn));
d3e2ba59
JD
1753 if (ret < 0) {
1754 goto error;
1755 }
58eb9381
DG
1756 conn->sessions_ht = sessions_ht;
1757 connection_init(conn);
1758 lttng_poll_add(&events, conn->sock->fd,
1759 LPOLLIN | LPOLLRDHUP);
1760 rcu_read_lock();
1761 lttng_ht_add_unique_ulong(relay_connections_ht,
1762 &conn->sock_n);
d3e2ba59 1763 rcu_read_unlock();
58eb9381 1764 DBG("Connection socket %d added", conn->sock->fd);
d3e2ba59 1765 }
58eb9381
DG
1766 } else {
1767 rcu_read_lock();
1768 conn = connection_find_by_sock(relay_connections_ht, pollfd);
1769 /* If not found, there is a synchronization issue. */
1770 assert(conn);
1771
1772 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1773 cleanup_connection_pollfd(&events, pollfd);
1774 destroy_connection(relay_connections_ht, conn);
d3e2ba59 1775 } else if (revents & LPOLLIN) {
58eb9381
DG
1776 ret = conn->sock->ops->recvmsg(conn->sock, &recv_hdr,
1777 sizeof(recv_hdr), 0);
d3e2ba59 1778 if (ret <= 0) {
58eb9381
DG
1779 /* Connection closed */
1780 cleanup_connection_pollfd(&events, pollfd);
1781 destroy_connection(relay_connections_ht, conn);
1782 DBG("Viewer control conn closed with %d", pollfd);
d3e2ba59 1783 } else {
58eb9381 1784 ret = process_control(&recv_hdr, conn);
d3e2ba59
JD
1785 if (ret < 0) {
1786 /* Clear the session on error. */
58eb9381
DG
1787 cleanup_connection_pollfd(&events, pollfd);
1788 destroy_connection(relay_connections_ht, conn);
d3e2ba59
JD
1789 DBG("Viewer connection closed with %d", pollfd);
1790 }
1791 }
1792 }
1793 rcu_read_unlock();
1794 }
1795 }
1796 }
1797
1798exit:
1799error:
1800 lttng_poll_clean(&events);
1801
58eb9381 1802 /* Cleanup reamaining connection object. */
d3e2ba59 1803 rcu_read_lock();
58eb9381
DG
1804 cds_lfht_for_each_entry(relay_connections_ht->ht, &iter.iter, conn,
1805 sock_n.node) {
eea7556c 1806 health_code_update();
58eb9381 1807 destroy_connection(relay_connections_ht, conn);
d3e2ba59
JD
1808 }
1809 rcu_read_unlock();
1810error_poll_create:
1811 lttng_ht_destroy(relay_connections_ht);
1812relay_connections_ht_error:
58eb9381
DG
1813 /* Close relay conn pipes */
1814 utils_close_pipe(live_conn_pipe);
d3e2ba59
JD
1815 if (err) {
1816 DBG("Viewer worker thread exited with error");
1817 }
1818 DBG("Viewer worker thread cleanup complete");
9b5e0863 1819error_testpoint:
eea7556c
MD
1820 if (err) {
1821 health_error();
1822 ERR("Health error occurred in %s", __func__);
1823 }
1824 health_unregister(health_relayd);
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1825 stop_threads();
1826 rcu_unregister_thread();
1827 return NULL;
1828}
1829
1830/*
1831 * Create the relay command pipe to wake thread_manage_apps.
1832 * Closed in cleanup().
1833 */
58eb9381 1834static int create_conn_pipe(void)
d3e2ba59
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1835{
1836 int ret;
1837
58eb9381 1838 ret = utils_create_pipe_cloexec(live_conn_pipe);
d3e2ba59
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1839
1840 return ret;
1841}
1842
aaec7998 1843void live_stop_threads(void)
d3e2ba59
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1844{
1845 int ret;
1846 void *status;
1847
1848 stop_threads();
1849
1850 ret = pthread_join(live_listener_thread, &status);
1851 if (ret != 0) {
1852 PERROR("pthread_join live listener");
1853 goto error; /* join error, exit without cleanup */
1854 }
1855
1856 ret = pthread_join(live_worker_thread, &status);
1857 if (ret != 0) {
1858 PERROR("pthread_join live worker");
1859 goto error; /* join error, exit without cleanup */
1860 }
1861
1862 ret = pthread_join(live_dispatcher_thread, &status);
1863 if (ret != 0) {
1864 PERROR("pthread_join live dispatcher");
1865 goto error; /* join error, exit without cleanup */
1866 }
1867
1868 cleanup();
1869
1870error:
1871 return;
1872}
1873
1874/*
1875 * main
1876 */
1877int live_start_threads(struct lttng_uri *uri,
0b242f62 1878 struct relay_local_data *relay_ctx)
d3e2ba59
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1879{
1880 int ret = 0;
1881 void *status;
1882 int is_root;
1883
1884 assert(uri);
1885 live_uri = uri;
1886
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1887 /* Check if daemon is UID = 0 */
1888 is_root = !getuid();
1889
1890 if (!is_root) {
1891 if (live_uri->port < 1024) {
1892 ERR("Need to be root to use ports < 1024");
1893 ret = -1;
1894 goto exit;
1895 }
1896 }
1897
1898 /* Setup the thread apps communication pipe. */
58eb9381 1899 if ((ret = create_conn_pipe()) < 0) {
d3e2ba59
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1900 goto exit;
1901 }
1902
1903 /* Init relay command queue. */
58eb9381 1904 cds_wfq_init(&viewer_conn_queue.queue);
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1905
1906 /* Set up max poll set size */
1907 lttng_poll_set_max_size();
1908
1909 /* Setup the dispatcher thread */
1910 ret = pthread_create(&live_dispatcher_thread, NULL,
1911 thread_dispatcher, (void *) NULL);
1912 if (ret != 0) {
1913 PERROR("pthread_create viewer dispatcher");
1914 goto exit_dispatcher;
1915 }
1916
1917 /* Setup the worker thread */
1918 ret = pthread_create(&live_worker_thread, NULL,
1919 thread_worker, relay_ctx);
1920 if (ret != 0) {
1921 PERROR("pthread_create viewer worker");
1922 goto exit_worker;
1923 }
1924
1925 /* Setup the listener thread */
1926 ret = pthread_create(&live_listener_thread, NULL,
1927 thread_listener, (void *) NULL);
1928 if (ret != 0) {
1929 PERROR("pthread_create viewer listener");
1930 goto exit_listener;
1931 }
1932
1933 ret = 0;
1934 goto end;
1935
1936exit_listener:
1937 ret = pthread_join(live_listener_thread, &status);
1938 if (ret != 0) {
1939 PERROR("pthread_join live listener");
1940 goto error; /* join error, exit without cleanup */
1941 }
1942
1943exit_worker:
1944 ret = pthread_join(live_worker_thread, &status);
1945 if (ret != 0) {
1946 PERROR("pthread_join live worker");
1947 goto error; /* join error, exit without cleanup */
1948 }
1949
1950exit_dispatcher:
1951 ret = pthread_join(live_dispatcher_thread, &status);
1952 if (ret != 0) {
1953 PERROR("pthread_join live dispatcher");
1954 goto error; /* join error, exit without cleanup */
1955 }
1956
1957exit:
1958 cleanup();
1959
1960end:
1961error:
1962 return ret;
1963}
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