src/bin/lttng-relayd/live.c

   1 /*
   2  * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
   3  *                      David Goulet <dgoulet@efficios.com>
   4  *               2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #define _LGPL_SOURCE
  21 #include <getopt.h>
  22 #include <grp.h>
  23 #include <limits.h>
  24 #include <pthread.h>
  25 #include <signal.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <sys/mman.h>
  30 #include <sys/mount.h>
  31 #include <sys/resource.h>
  32 #include <sys/socket.h>
  33 #include <sys/stat.h>
  34 #include <sys/types.h>
  35 #include <sys/wait.h>
  36 #include <inttypes.h>
  37 #include <urcu/futex.h>
  38 #include <urcu/uatomic.h>
  39 #include <urcu/rculist.h>
  40 #include <unistd.h>
  41 #include <fcntl.h>
  42
  43 #include <lttng/lttng.h>
  44 #include <common/common.h>
  45 #include <common/compat/poll.h>
  46 #include <common/compat/socket.h>
  47 #include <common/compat/endian.h>
  48 #include <common/defaults.h>
  49 #include <common/futex.h>
  50 #include <common/index/index.h>
  51 #include <common/sessiond-comm/sessiond-comm.h>
  52 #include <common/sessiond-comm/inet.h>
  53 #include <common/sessiond-comm/relayd.h>
  54 #include <common/uri.h>
  55 #include <common/utils.h>
  56
  57 #include "cmd.h"
  58 #include "live.h"
  59 #include "lttng-relayd.h"
  60 #include "utils.h"
  61 #include "health-relayd.h"
  62 #include "testpoint.h"
  63 #include "viewer-stream.h"
  64 #include "stream.h"
  65 #include "session.h"
  66 #include "ctf-trace.h"
  67 #include "connection.h"
  68 #include "viewer-session.h"
  69
  70 #define SESSION_BUF_DEFAULT_COUNT       16
  71
  72 static struct lttng_uri *live_uri;
  73
  74 /*
  75  * This pipe is used to inform the worker thread that a command is queued and
  76  * ready to be processed.
  77  */
  78 static int live_conn_pipe[2] = { -1, -1 };
  79
  80 /* Shared between threads */
  81 static int live_dispatch_thread_exit;
  82
  83 static pthread_t live_listener_thread;
  84 static pthread_t live_dispatcher_thread;
  85 static pthread_t live_worker_thread;
  86
  87 /*
  88  * Relay command queue.
  89  *
  90  * The live_thread_listener and live_thread_dispatcher communicate with this
  91  * queue.
  92  */
  93 static struct relay_conn_queue viewer_conn_queue;
  94
  95 static uint64_t last_relay_viewer_session_id;
  96 static pthread_mutex_t last_relay_viewer_session_id_lock =
  97                 PTHREAD_MUTEX_INITIALIZER;
  98
  99 /*
 100  * Cleanup the daemon
 101  */
 102 static
 103 void cleanup_relayd_live(void)
 104 {
 105         DBG("Cleaning up");
 106
 107         free(live_uri);
 108 }
 109
 110 /*
 111  * Receive a request buffer using a given socket, destination allocated buffer
 112  * of length size.
 113  *
 114  * Return the size of the received message or else a negative value on error
 115  * with errno being set by recvmsg() syscall.
 116  */
 117 static
 118 ssize_t recv_request(struct lttcomm_sock *sock, void *buf, size_t size)
 119 {
 120         ssize_t ret;
 121
 122         ret = sock->ops->recvmsg(sock, buf, size, 0);
 123         if (ret < 0 || ret != size) {
 124                 if (ret == 0) {
 125                         /* Orderly shutdown. Not necessary to print an error. */
 126                         DBG("Socket %d did an orderly shutdown", sock->fd);
 127                 } else {
 128                         ERR("Relay failed to receive request.");
 129                 }
 130                 ret = -1;
 131         }
 132
 133         return ret;
 134 }
 135
 136 /*
 137  * Send a response buffer using a given socket, source allocated buffer of
 138  * length size.
 139  *
 140  * Return the size of the sent message or else a negative value on error with
 141  * errno being set by sendmsg() syscall.
 142  */
 143 static
 144 ssize_t send_response(struct lttcomm_sock *sock, void *buf, size_t size)
 145 {
 146         ssize_t ret;
 147
 148         ret = sock->ops->sendmsg(sock, buf, size, 0);
 149         if (ret < 0) {
 150                 ERR("Relayd failed to send response.");
 151         }
 152
 153         return ret;
 154 }
 155
 156 /*
 157  * Atomically check if new streams got added in one of the sessions attached
 158  * and reset the flag to 0.
 159  *
 160  * Returns 1 if new streams got added, 0 if nothing changed, a negative value
 161  * on error.
 162  */
 163 static
 164 int check_new_streams(struct relay_connection *conn)
 165 {
 166         struct relay_session *session;
 167         unsigned long current_val;
 168         int ret = 0;
 169
 170         if (!conn->viewer_session) {
 171                 goto end;
 172         }
 173         rcu_read_lock();
 174         cds_list_for_each_entry_rcu(session,
 175                         &conn->viewer_session->session_list,
 176                         viewer_session_node) {
 177                 if (!session_get(session)) {
 178                         continue;
 179                 }
 180                 current_val = uatomic_cmpxchg(&session->new_streams, 1, 0);
 181                 ret = current_val;
 182                 session_put(session);
 183                 if (ret == 1) {
 184                         goto end;
 185                 }
 186         }
 187 end:
 188         rcu_read_unlock();
 189         return ret;
 190 }
 191
 192 /*
 193  * Send viewer streams to the given socket. The ignore_sent_flag indicates if
 194  * this function should ignore the sent flag or not.
 195  *
 196  * Return 0 on success or else a negative value.
 197  */
 198 static
 199 ssize_t send_viewer_streams(struct lttcomm_sock *sock,
 200                 struct relay_session *session, unsigned int ignore_sent_flag)
 201 {
 202         ssize_t ret;
 203         struct lttng_viewer_stream send_stream;
 204         struct lttng_ht_iter iter;
 205         struct relay_viewer_stream *vstream;
 206
 207         rcu_read_lock();
 208
 209         cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter, vstream,
 210                         stream_n.node) {
 211                 struct ctf_trace *ctf_trace;
 212
 213                 health_code_update();
 214
 215                 if (!viewer_stream_get(vstream)) {
 216                         continue;
 217                 }
 218
 219                 pthread_mutex_lock(&vstream->stream->lock);
 220                 /* Ignore if not the same session. */
 221                 if (vstream->stream->trace->session->id != session->id ||
 222                                 (!ignore_sent_flag && vstream->sent_flag)) {
 223                         pthread_mutex_unlock(&vstream->stream->lock);
 224                         viewer_stream_put(vstream);
 225                         continue;
 226                 }
 227
 228                 ctf_trace = vstream->stream->trace;
 229                 send_stream.id = htobe64(vstream->stream->stream_handle);
 230                 send_stream.ctf_trace_id = htobe64(ctf_trace->id);
 231                 send_stream.metadata_flag = htobe32(
 232                                 vstream->stream->is_metadata);
 233                 if (lttng_strncpy(send_stream.path_name, vstream->path_name,
 234                                 sizeof(send_stream.path_name))) {
 235                         pthread_mutex_unlock(&vstream->stream->lock);
 236                         viewer_stream_put(vstream);
 237                         ret = -1;       /* Error. */
 238                         goto end_unlock;
 239                 }
 240                 if (lttng_strncpy(send_stream.channel_name,
 241                                 vstream->channel_name,
 242                                 sizeof(send_stream.channel_name))) {
 243                         pthread_mutex_unlock(&vstream->stream->lock);
 244                         viewer_stream_put(vstream);
 245                         ret = -1;       /* Error. */
 246                         goto end_unlock;
 247                 }
 248
 249                 DBG("Sending stream %" PRIu64 " to viewer",
 250                                 vstream->stream->stream_handle);
 251                 vstream->sent_flag = 1;
 252                 pthread_mutex_unlock(&vstream->stream->lock);
 253
 254                 ret = send_response(sock, &send_stream, sizeof(send_stream));
 255                 viewer_stream_put(vstream);
 256                 if (ret < 0) {
 257                         goto end_unlock;
 258                 }
 259         }
 260
 261         ret = 0;
 262
 263 end_unlock:
 264         rcu_read_unlock();
 265         return ret;
 266 }
 267
 268 /*
 269  * Create every viewer stream possible for the given session with the seek
 270  * type. Three counters *can* be return which are in order the total amount of
 271  * viewer stream of the session, the number of unsent stream and the number of
 272  * stream created. Those counters can be NULL and thus will be ignored.
 273  *
 274  * Return 0 on success or else a negative value.
 275  */
 276 static
 277 int make_viewer_streams(struct relay_session *session,
 278                 enum lttng_viewer_seek seek_t, uint32_t *nb_total, uint32_t *nb_unsent,
 279                 uint32_t *nb_created, bool *closed)
 280 {
 281         int ret;
 282         struct lttng_ht_iter iter;
 283         struct ctf_trace *ctf_trace;
 284
 285         assert(session);
 286
 287         /*
 288          * Hold the session lock to ensure that we see either none or
 289          * all initial streams for a session, but no intermediate state.
 290          */
 291         pthread_mutex_lock(&session->lock);
 292
 293         if (session->connection_closed) {
 294                 *closed = true;
 295         }
 296
 297         /*
 298          * Create viewer streams for relay streams that are ready to be
 299          * used for a the given session id only.
 300          */
 301         rcu_read_lock();
 302         cds_lfht_for_each_entry(session->ctf_traces_ht->ht, &iter.iter, ctf_trace,
 303                         node.node) {
 304                 struct relay_stream *stream;
 305
 306                 health_code_update();
 307
 308                 if (!ctf_trace_get(ctf_trace)) {
 309                         continue;
 310                 }
 311
 312                 cds_list_for_each_entry_rcu(stream, &ctf_trace->stream_list, stream_node) {
 313                         struct relay_viewer_stream *vstream;
 314
 315                         if (!stream_get(stream)) {
 316                                 continue;
 317                         }
 318                         /*
 319                          * stream published is protected by the session lock.
 320                          */
 321                         if (!stream->published) {
 322                                 goto next;
 323                         }
 324                         vstream = viewer_stream_get_by_id(stream->stream_handle);
 325                         if (!vstream) {
 326                                 vstream = viewer_stream_create(stream, seek_t);
 327                                 if (!vstream) {
 328                                         ret = -1;
 329                                         ctf_trace_put(ctf_trace);
 330                                         stream_put(stream);
 331                                         goto error_unlock;
 332                                 }
 333
 334                                 if (nb_created) {
 335                                         /* Update number of created stream counter. */
 336                                         (*nb_created)++;
 337                                 }
 338                                 /*
 339                                  * Ensure a self-reference is preserved even
 340                                  * after we have put our local reference.
 341                                  */
 342                                 if (!viewer_stream_get(vstream)) {
 343                                         ERR("Unable to get self-reference on viewer stream, logic error.");
 344                                         abort();
 345                                 }
 346                         } else {
 347                                 if (!vstream->sent_flag && nb_unsent) {
 348                                         /* Update number of unsent stream counter. */
 349                                         (*nb_unsent)++;
 350                                 }
 351                         }
 352                         /* Update number of total stream counter. */
 353                         if (nb_total) {
 354                                 if (stream->is_metadata) {
 355                                         if (!stream->closed ||
 356                                                         stream->metadata_received > vstream->metadata_sent) {
 357                                                 (*nb_total)++;
 358                                         }
 359                                 } else {
 360                                         if (!stream->closed ||
 361                                                 !(((int64_t) (stream->prev_seq - stream->last_net_seq_num)) >= 0)) {
 362
 363                                                 (*nb_total)++;
 364                                         }
 365                                 }
 366                         }
 367                         /* Put local reference. */
 368                         viewer_stream_put(vstream);
 369                 next:
 370                         stream_put(stream);
 371                 }
 372                 ctf_trace_put(ctf_trace);
 373         }
 374
 375         ret = 0;
 376
 377 error_unlock:
 378         rcu_read_unlock();
 379         pthread_mutex_unlock(&session->lock);
 380         return ret;
 381 }
 382
 383 int relayd_live_stop(void)
 384 {
 385         /* Stop dispatch thread */
 386         CMM_STORE_SHARED(live_dispatch_thread_exit, 1);
 387         futex_nto1_wake(&viewer_conn_queue.futex);
 388         return 0;
 389 }
 390
 391 /*
 392  * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
 393  */
 394 static
 395 int create_thread_poll_set(struct lttng_poll_event *events, int size)
 396 {
 397         int ret;
 398
 399         if (events == NULL || size == 0) {
 400                 ret = -1;
 401                 goto error;
 402         }
 403
 404         ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
 405         if (ret < 0) {
 406                 goto error;
 407         }
 408
 409         /* Add quit pipe */
 410         ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN | LPOLLERR);
 411         if (ret < 0) {
 412                 goto error;
 413         }
 414
 415         return 0;
 416
 417 error:
 418         return ret;
 419 }
 420
 421 /*
 422  * Check if the thread quit pipe was triggered.
 423  *
 424  * Return 1 if it was triggered else 0;
 425  */
 426 static
 427 int check_thread_quit_pipe(int fd, uint32_t events)
 428 {
 429         if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
 430                 return 1;
 431         }
 432
 433         return 0;
 434 }
 435
 436 /*
 437  * Create and init socket from uri.
 438  */
 439 static
 440 struct lttcomm_sock *init_socket(struct lttng_uri *uri)
 441 {
 442         int ret;
 443         struct lttcomm_sock *sock = NULL;
 444
 445         sock = lttcomm_alloc_sock_from_uri(uri);
 446         if (sock == NULL) {
 447                 ERR("Allocating socket");
 448                 goto error;
 449         }
 450
 451         ret = lttcomm_create_sock(sock);
 452         if (ret < 0) {
 453                 goto error;
 454         }
 455         DBG("Listening on sock %d for live", sock->fd);
 456
 457         ret = sock->ops->bind(sock);
 458         if (ret < 0) {
 459                 goto error;
 460         }
 461
 462         ret = sock->ops->listen(sock, -1);
 463         if (ret < 0) {
 464                 goto error;
 465
 466         }
 467
 468         return sock;
 469
 470 error:
 471         if (sock) {
 472                 lttcomm_destroy_sock(sock);
 473         }
 474         return NULL;
 475 }
 476
 477 /*
 478  * This thread manages the listening for new connections on the network
 479  */
 480 static
 481 void *thread_listener(void *data)
 482 {
 483         int i, ret, pollfd, err = -1;
 484         uint32_t revents, nb_fd;
 485         struct lttng_poll_event events;
 486         struct lttcomm_sock *live_control_sock;
 487
 488         DBG("[thread] Relay live listener started");
 489
 490         health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_LISTENER);
 491
 492         health_code_update();
 493
 494         live_control_sock = init_socket(live_uri);
 495         if (!live_control_sock) {
 496                 goto error_sock_control;
 497         }
 498
 499         /* Pass 2 as size here for the thread quit pipe and control sockets. */
 500         ret = create_thread_poll_set(&events, 2);
 501         if (ret < 0) {
 502                 goto error_create_poll;
 503         }
 504
 505         /* Add the control socket */
 506         ret = lttng_poll_add(&events, live_control_sock->fd, LPOLLIN | LPOLLRDHUP);
 507         if (ret < 0) {
 508                 goto error_poll_add;
 509         }
 510
 511         lttng_relay_notify_ready();
 512
 513         if (testpoint(relayd_thread_live_listener)) {
 514                 goto error_testpoint;
 515         }
 516
 517         while (1) {
 518                 health_code_update();
 519
 520                 DBG("Listener accepting live viewers connections");
 521
 522 restart:
 523                 health_poll_entry();
 524                 ret = lttng_poll_wait(&events, -1);
 525                 health_poll_exit();
 526                 if (ret < 0) {
 527                         /*
 528                          * Restart interrupted system call.
 529                          */
 530                         if (errno == EINTR) {
 531                                 goto restart;
 532                         }
 533                         goto error;
 534                 }
 535                 nb_fd = ret;
 536
 537                 DBG("Relay new viewer connection received");
 538                 for (i = 0; i < nb_fd; i++) {
 539                         health_code_update();
 540
 541                         /* Fetch once the poll data */
 542                         revents = LTTNG_POLL_GETEV(&events, i);
 543                         pollfd = LTTNG_POLL_GETFD(&events, i);
 544
 545                         if (!revents) {
 546                                 /* No activity for this FD (poll implementation). */
 547                                 continue;
 548                         }
 549
 550                         /* Thread quit pipe has been closed. Killing thread. */
 551                         ret = check_thread_quit_pipe(pollfd, revents);
 552                         if (ret) {
 553                                 err = 0;
 554                                 goto exit;
 555                         }
 556
 557                         if (revents & LPOLLIN) {
 558                                 /*
 559                                  * A new connection is requested, therefore a
 560                                  * viewer connection is allocated in this
 561                                  * thread, enqueued to a global queue and
 562                                  * dequeued (and freed) in the worker thread.
 563                                  */
 564                                 int val = 1;
 565                                 struct relay_connection *new_conn;
 566                                 struct lttcomm_sock *newsock;
 567
 568                                 newsock = live_control_sock->ops->accept(live_control_sock);
 569                                 if (!newsock) {
 570                                         PERROR("accepting control sock");
 571                                         goto error;
 572                                 }
 573                                 DBG("Relay viewer connection accepted socket %d", newsock->fd);
 574
 575                                 ret = setsockopt(newsock->fd, SOL_SOCKET, SO_REUSEADDR, &val,
 576                                                 sizeof(val));
 577                                 if (ret < 0) {
 578                                         PERROR("setsockopt inet");
 579                                         lttcomm_destroy_sock(newsock);
 580                                         goto error;
 581                                 }
 582                                 new_conn = connection_create(newsock, RELAY_CONNECTION_UNKNOWN);
 583                                 if (!new_conn) {
 584                                         lttcomm_destroy_sock(newsock);
 585                                         goto error;
 586                                 }
 587                                 /* Ownership assumed by the connection. */
 588                                 newsock = NULL;
 589
 590                                 /* Enqueue request for the dispatcher thread. */
 591                                 cds_wfcq_enqueue(&viewer_conn_queue.head, &viewer_conn_queue.tail,
 592                                                  &new_conn->qnode);
 593
 594                                 /*
 595                                  * Wake the dispatch queue futex.
 596                                  * Implicit memory barrier with the
 597                                  * exchange in cds_wfcq_enqueue.
 598                                  */
 599                                 futex_nto1_wake(&viewer_conn_queue.futex);
 600                         } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
 601                                 ERR("socket poll error");
 602                                 goto error;
 603                         } else {
 604                                 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
 605                                 goto error;
 606                         }
 607                 }
 608         }
 609
 610 exit:
 611 error:
 612 error_poll_add:
 613 error_testpoint:
 614         lttng_poll_clean(&events);
 615 error_create_poll:
 616         if (live_control_sock->fd >= 0) {
 617                 ret = live_control_sock->ops->close(live_control_sock);
 618                 if (ret) {
 619                         PERROR("close");
 620                 }
 621         }
 622         lttcomm_destroy_sock(live_control_sock);
 623 error_sock_control:
 624         if (err) {
 625                 health_error();
 626                 DBG("Live viewer listener thread exited with error");
 627         }
 628         health_unregister(health_relayd);
 629         DBG("Live viewer listener thread cleanup complete");
 630         if (lttng_relay_stop_threads()) {
 631                 ERR("Error stopping threads");
 632         }
 633         return NULL;
 634 }
 635
 636 /*
 637  * This thread manages the dispatching of the requests to worker threads
 638  */
 639 static
 640 void *thread_dispatcher(void *data)
 641 {
 642         int err = -1;
 643         ssize_t ret;
 644         struct cds_wfcq_node *node;
 645         struct relay_connection *conn = NULL;
 646
 647         DBG("[thread] Live viewer relay dispatcher started");
 648
 649         health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_DISPATCHER);
 650
 651         if (testpoint(relayd_thread_live_dispatcher)) {
 652                 goto error_testpoint;
 653         }
 654
 655         health_code_update();
 656
 657         for (;;) {
 658                 health_code_update();
 659
 660                 /* Atomically prepare the queue futex */
 661                 futex_nto1_prepare(&viewer_conn_queue.futex);
 662
 663                 if (CMM_LOAD_SHARED(live_dispatch_thread_exit)) {
 664                         break;
 665                 }
 666
 667                 do {
 668                         health_code_update();
 669
 670                         /* Dequeue commands */
 671                         node = cds_wfcq_dequeue_blocking(&viewer_conn_queue.head,
 672                                                          &viewer_conn_queue.tail);
 673                         if (node == NULL) {
 674                                 DBG("Woken up but nothing in the live-viewer "
 675                                                 "relay command queue");
 676                                 /* Continue thread execution */
 677                                 break;
 678                         }
 679                         conn = caa_container_of(node, struct relay_connection, qnode);
 680                         DBG("Dispatching viewer request waiting on sock %d",
 681                                         conn->sock->fd);
 682
 683                         /*
 684                          * Inform worker thread of the new request. This
 685                          * call is blocking so we can be assured that
 686                          * the data will be read at some point in time
 687                          * or wait to the end of the world :)
 688                          */
 689                         ret = lttng_write(live_conn_pipe[1], &conn, sizeof(conn));
 690                         if (ret < 0) {
 691                                 PERROR("write conn pipe");
 692                                 connection_put(conn);
 693                                 goto error;
 694                         }
 695                 } while (node != NULL);
 696
 697                 /* Futex wait on queue. Blocking call on futex() */
 698                 health_poll_entry();
 699                 futex_nto1_wait(&viewer_conn_queue.futex);
 700                 health_poll_exit();
 701         }
 702
 703         /* Normal exit, no error */
 704         err = 0;
 705
 706 error:
 707 error_testpoint:
 708         if (err) {
 709                 health_error();
 710                 ERR("Health error occurred in %s", __func__);
 711         }
 712         health_unregister(health_relayd);
 713         DBG("Live viewer dispatch thread dying");
 714         if (lttng_relay_stop_threads()) {
 715                 ERR("Error stopping threads");
 716         }
 717         return NULL;
 718 }
 719
 720 /*
 721  * Establish connection with the viewer and check the versions.
 722  *
 723  * Return 0 on success or else negative value.
 724  */
 725 static
 726 int viewer_connect(struct relay_connection *conn)
 727 {
 728         int ret;
 729         struct lttng_viewer_connect reply, msg;
 730
 731         conn->version_check_done = 1;
 732
 733         health_code_update();
 734
 735         DBG("Viewer is establishing a connection to the relayd.");
 736
 737         ret = recv_request(conn->sock, &msg, sizeof(msg));
 738         if (ret < 0) {
 739                 goto end;
 740         }
 741
 742         health_code_update();
 743
 744         memset(&reply, 0, sizeof(reply));
 745         reply.major = RELAYD_VERSION_COMM_MAJOR;
 746         reply.minor = RELAYD_VERSION_COMM_MINOR;
 747
 748         /* Major versions must be the same */
 749         if (reply.major != be32toh(msg.major)) {
 750                 DBG("Incompatible major versions ([relayd] %u vs [client] %u)",
 751                                 reply.major, be32toh(msg.major));
 752                 ret = -1;
 753                 goto end;
 754         }
 755
 756         conn->major = reply.major;
 757         /* We adapt to the lowest compatible version */
 758         if (reply.minor <= be32toh(msg.minor)) {
 759                 conn->minor = reply.minor;
 760         } else {
 761                 conn->minor = be32toh(msg.minor);
 762         }
 763
 764         if (be32toh(msg.type) == LTTNG_VIEWER_CLIENT_COMMAND) {
 765                 conn->type = RELAY_VIEWER_COMMAND;
 766         } else if (be32toh(msg.type) == LTTNG_VIEWER_CLIENT_NOTIFICATION) {
 767                 conn->type = RELAY_VIEWER_NOTIFICATION;
 768         } else {
 769                 ERR("Unknown connection type : %u", be32toh(msg.type));
 770                 ret = -1;
 771                 goto end;
 772         }
 773
 774         reply.major = htobe32(reply.major);
 775         reply.minor = htobe32(reply.minor);
 776         if (conn->type == RELAY_VIEWER_COMMAND) {
 777                 /*
 778                  * Increment outside of htobe64 macro, because the argument can
 779                  * be used more than once within the macro, and thus the
 780                  * operation may be undefined.
 781                  */
 782                 pthread_mutex_lock(&last_relay_viewer_session_id_lock);
 783                 last_relay_viewer_session_id++;
 784                 pthread_mutex_unlock(&last_relay_viewer_session_id_lock);
 785                 reply.viewer_session_id = htobe64(last_relay_viewer_session_id);
 786         }
 787
 788         health_code_update();
 789
 790         ret = send_response(conn->sock, &reply, sizeof(reply));
 791         if (ret < 0) {
 792                 goto end;
 793         }
 794
 795         health_code_update();
 796
 797         DBG("Version check done using protocol %u.%u", conn->major, conn->minor);
 798         ret = 0;
 799
 800 end:
 801         return ret;
 802 }
 803
 804 /*
 805  * Send the viewer the list of current sessions.
 806  * We need to create a copy of the hash table content because otherwise
 807  * we cannot assume the number of entries stays the same between getting
 808  * the number of HT elements and iteration over the HT.
 809  *
 810  * Return 0 on success or else a negative value.
 811  */
 812 static
 813 int viewer_list_sessions(struct relay_connection *conn)
 814 {
 815         int ret = 0;
 816         struct lttng_viewer_list_sessions session_list;
 817         struct lttng_ht_iter iter;
 818         struct relay_session *session;
 819         struct lttng_viewer_session *send_session_buf = NULL;
 820         uint32_t buf_count = SESSION_BUF_DEFAULT_COUNT;
 821         uint32_t count = 0;
 822
 823         DBG("List sessions received");
 824
 825         send_session_buf = zmalloc(SESSION_BUF_DEFAULT_COUNT * sizeof(*send_session_buf));
 826         if (!send_session_buf) {
 827                 return -1;
 828         }
 829
 830         rcu_read_lock();
 831         cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, session,
 832                         session_n.node) {
 833                 struct lttng_viewer_session *send_session;
 834
 835                 health_code_update();
 836
 837                 if (count >= buf_count) {
 838                         struct lttng_viewer_session *newbuf;
 839                         uint32_t new_buf_count = buf_count << 1;
 840
 841                         newbuf = realloc(send_session_buf,
 842                                 new_buf_count * sizeof(*send_session_buf));
 843                         if (!newbuf) {
 844                                 ret = -1;
 845                                 break;
 846                         }
 847                         send_session_buf = newbuf;
 848                         buf_count = new_buf_count;
 849                 }
 850                 send_session = &send_session_buf[count];
 851                 if (lttng_strncpy(send_session->session_name,
 852                                 session->session_name,
 853                                 sizeof(send_session->session_name))) {
 854                         ret = -1;
 855                         break;
 856                 }
 857                 if (lttng_strncpy(send_session->hostname, session->hostname,
 858                                 sizeof(send_session->hostname))) {
 859                         ret = -1;
 860                         break;
 861                 }
 862                 send_session->id = htobe64(session->id);
 863                 send_session->live_timer = htobe32(session->live_timer);
 864                 if (session->viewer_attached) {
 865                         send_session->clients = htobe32(1);
 866                 } else {
 867                         send_session->clients = htobe32(0);
 868                 }
 869                 send_session->streams = htobe32(session->stream_count);
 870                 count++;
 871         }
 872         rcu_read_unlock();
 873         if (ret < 0) {
 874                 goto end_free;
 875         }
 876
 877         session_list.sessions_count = htobe32(count);
 878
 879         health_code_update();
 880
 881         ret = send_response(conn->sock, &session_list, sizeof(session_list));
 882         if (ret < 0) {
 883                 goto end_free;
 884         }
 885
 886         health_code_update();
 887
 888         ret = send_response(conn->sock, send_session_buf,
 889                         count * sizeof(*send_session_buf));
 890         if (ret < 0) {
 891                 goto end_free;
 892         }
 893         health_code_update();
 894
 895         ret = 0;
 896 end_free:
 897         free(send_session_buf);
 898         return ret;
 899 }
 900
 901 /*
 902  * Send the viewer the list of current streams.
 903  */
 904 static
 905 int viewer_get_new_streams(struct relay_connection *conn)
 906 {
 907         int ret, send_streams = 0;
 908         uint32_t nb_created = 0, nb_unsent = 0, nb_streams = 0, nb_total = 0;
 909         struct lttng_viewer_new_streams_request request;
 910         struct lttng_viewer_new_streams_response response;
 911         struct relay_session *session;
 912         uint64_t session_id;
 913         bool closed = false;
 914
 915         assert(conn);
 916
 917         DBG("Get new streams received");
 918
 919         health_code_update();
 920
 921         /* Receive the request from the connected client. */
 922         ret = recv_request(conn->sock, &request, sizeof(request));
 923         if (ret < 0) {
 924                 goto error;
 925         }
 926         session_id = be64toh(request.session_id);
 927
 928         health_code_update();
 929
 930         memset(&response, 0, sizeof(response));
 931
 932         session = session_get_by_id(session_id);
 933         if (!session) {
 934                 DBG("Relay session %" PRIu64 " not found", session_id);
 935                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR);
 936                 goto send_reply;
 937         }
 938
 939         if (!viewer_session_is_attached(conn->viewer_session, session)) {
 940                 send_streams = 0;
 941                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR);
 942                 goto send_reply;
 943         }
 944
 945         send_streams = 1;
 946         response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_OK);
 947
 948         ret = make_viewer_streams(session, LTTNG_VIEWER_SEEK_LAST, &nb_total, &nb_unsent,
 949                         &nb_created, &closed);
 950         if (ret < 0) {
 951                 goto end_put_session;
 952         }
 953         /* Only send back the newly created streams with the unsent ones. */
 954         nb_streams = nb_created + nb_unsent;
 955         response.streams_count = htobe32(nb_streams);
 956
 957         /*
 958          * If the session is closed, HUP when there are no more streams
 959          * with data.
 960          */
 961         if (closed && nb_total == 0) {
 962                 send_streams = 0;
 963                 response.streams_count = 0;
 964                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_HUP);
 965                 goto send_reply;
 966         }
 967
 968 send_reply:
 969         health_code_update();
 970         ret = send_response(conn->sock, &response, sizeof(response));
 971         if (ret < 0) {
 972                 goto end_put_session;
 973         }
 974         health_code_update();
 975
 976         /*
 977          * Unknown or empty session, just return gracefully, the viewer
 978          * knows what is happening.
 979          */
 980         if (!send_streams || !nb_streams) {
 981                 ret = 0;
 982                 goto end_put_session;
 983         }
 984
 985         /*
 986          * Send stream and *DON'T* ignore the sent flag so every viewer
 987          * streams that were not sent from that point will be sent to
 988          * the viewer.
 989          */
 990         ret = send_viewer_streams(conn->sock, session, 0);
 991         if (ret < 0) {
 992                 goto end_put_session;
 993         }
 994
 995 end_put_session:
 996         if (session) {
 997                 session_put(session);
 998         }
 999 error:
1000         return ret;
1001 }
1002
1003 /*
1004  * Send the viewer the list of current sessions.
1005  */
1006 static
1007 int viewer_attach_session(struct relay_connection *conn)
1008 {
1009         int send_streams = 0;
1010         ssize_t ret;
1011         uint32_t nb_streams = 0;
1012         enum lttng_viewer_seek seek_type;
1013         struct lttng_viewer_attach_session_request request;
1014         struct lttng_viewer_attach_session_response response;
1015         struct relay_session *session = NULL;
1016         bool closed = false;
1017
1018         assert(conn);
1019
1020         health_code_update();
1021
1022         /* Receive the request from the connected client. */
1023         ret = recv_request(conn->sock, &request, sizeof(request));
1024         if (ret < 0) {
1025                 goto error;
1026         }
1027
1028         health_code_update();
1029
1030         memset(&response, 0, sizeof(response));
1031
1032         if (!conn->viewer_session) {
1033                 DBG("Client trying to attach before creating a live viewer session");
1034                 response.status = htobe32(LTTNG_VIEWER_ATTACH_NO_SESSION);
1035                 goto send_reply;
1036         }
1037
1038         session = session_get_by_id(be64toh(request.session_id));
1039         if (!session) {
1040                 DBG("Relay session %" PRIu64 " not found",
1041                                 be64toh(request.session_id));
1042                 response.status = htobe32(LTTNG_VIEWER_ATTACH_UNK);
1043                 goto send_reply;
1044         }
1045         DBG("Attach session ID %" PRIu64 " received",
1046                 be64toh(request.session_id));
1047
1048         if (session->live_timer == 0) {
1049                 DBG("Not live session");
1050                 response.status = htobe32(LTTNG_VIEWER_ATTACH_NOT_LIVE);
1051                 goto send_reply;
1052         }
1053
1054         send_streams = 1;
1055         ret = viewer_session_attach(conn->viewer_session, session);
1056         if (ret) {
1057                 DBG("Already a viewer attached");
1058                 response.status = htobe32(LTTNG_VIEWER_ATTACH_ALREADY);
1059                 goto send_reply;
1060         }
1061
1062         switch (be32toh(request.seek)) {
1063         case LTTNG_VIEWER_SEEK_BEGINNING:
1064         case LTTNG_VIEWER_SEEK_LAST:
1065                 response.status = htobe32(LTTNG_VIEWER_ATTACH_OK);
1066                 seek_type = be32toh(request.seek);
1067                 break;
1068         default:
1069                 ERR("Wrong seek parameter");
1070                 response.status = htobe32(LTTNG_VIEWER_ATTACH_SEEK_ERR);
1071                 send_streams = 0;
1072                 goto send_reply;
1073         }
1074
1075         ret = make_viewer_streams(session, seek_type, &nb_streams, NULL,
1076                         NULL, &closed);
1077         if (ret < 0) {
1078                 goto end_put_session;
1079         }
1080         response.streams_count = htobe32(nb_streams);
1081
1082         /*
1083          * If the session is closed when the viewer is attaching, it
1084          * means some of the streams may have been concurrently removed,
1085          * so we don't allow the viewer to attach, even if there are
1086          * streams available.
1087          */
1088         if (closed) {
1089                 send_streams = 0;
1090                 response.streams_count = 0;
1091                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_HUP);
1092                 goto send_reply;
1093         }
1094
1095 send_reply:
1096         health_code_update();
1097         ret = send_response(conn->sock, &response, sizeof(response));
1098         if (ret < 0) {
1099                 goto end_put_session;
1100         }
1101         health_code_update();
1102
1103         /*
1104          * Unknown or empty session, just return gracefully, the viewer
1105          * knows what is happening.
1106          */
1107         if (!send_streams || !nb_streams) {
1108                 ret = 0;
1109                 goto end_put_session;
1110         }
1111
1112         /* Send stream and ignore the sent flag. */
1113         ret = send_viewer_streams(conn->sock, session, 1);
1114         if (ret < 0) {
1115                 goto end_put_session;
1116         }
1117
1118 end_put_session:
1119         if (session) {
1120                 session_put(session);
1121         }
1122 error:
1123         return ret;
1124 }
1125
1126 /*
1127  * Open the index file if needed for the given vstream.
1128  *
1129  * If an index file is successfully opened, the vstream will set it as its
1130  * current index file.
1131  *
1132  * Return 0 on success, a negative value on error (-ENOENT if not ready yet).
1133  *
1134  * Called with rstream lock held.
1135  */
1136 static int try_open_index(struct relay_viewer_stream *vstream,
1137                 struct relay_stream *rstream)
1138 {
1139         int ret = 0;
1140
1141         if (vstream->index_file) {
1142                 goto end;
1143         }
1144
1145         /*
1146          * First time, we open the index file and at least one index is ready.
1147          */
1148         if (rstream->index_received_seqcount == 0) {
1149                 ret = -ENOENT;
1150                 goto end;
1151         }
1152         vstream->index_file = lttng_index_file_open(vstream->path_name,
1153                         vstream->channel_name,
1154                         vstream->stream->tracefile_count,
1155                         vstream->current_tracefile_id);
1156         if (!vstream->index_file) {
1157                 ret = -1;
1158         }
1159
1160 end:
1161         return ret;
1162 }
1163
1164 /*
1165  * Check the status of the index for the given stream. This function
1166  * updates the index structure if needed and can put (close) the vstream
1167  * in the HUP situation.
1168  *
1169  * Return 0 means that we can proceed with the index. A value of 1 means
1170  * that the index has been updated and is ready to be sent to the
1171  * client. A negative value indicates an error that can't be handled.
1172  *
1173  * Called with rstream lock held.
1174  */
1175 static int check_index_status(struct relay_viewer_stream *vstream,
1176                 struct relay_stream *rstream, struct ctf_trace *trace,
1177                 struct lttng_viewer_index *index)
1178 {
1179         int ret;
1180
1181         if (trace->session->connection_closed
1182                         && rstream->index_received_seqcount
1183                                 == vstream->index_sent_seqcount) {
1184                 /* Last index sent and session connection is closed. */
1185                 index->status = htobe32(LTTNG_VIEWER_INDEX_HUP);
1186                 goto hup;
1187         } else if (rstream->beacon_ts_end != -1ULL &&
1188                         rstream->index_received_seqcount
1189                                 == vstream->index_sent_seqcount) {
1190                 /*
1191                  * We've received a synchronization beacon and the last index
1192                  * available has been sent, the index for now is inactive.
1193                  *
1194                  * In this case, we have received a beacon which allows us to
1195                  * inform the client of a time interval during which we can
1196                  * guarantee that there are no events to read (and never will
1197                  * be).
1198                  */
1199                 index->status = htobe32(LTTNG_VIEWER_INDEX_INACTIVE);
1200                 index->timestamp_end = htobe64(rstream->beacon_ts_end);
1201                 index->stream_id = htobe64(rstream->ctf_stream_id);
1202                 goto index_ready;
1203         } else if (rstream->index_received_seqcount
1204                         == vstream->index_sent_seqcount) {
1205                 /*
1206                  * This checks whether received == sent seqcount. In
1207                  * this case, we have not received a beacon. Therefore,
1208                  * we can only ask the client to retry later.
1209                  */
1210                 index->status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
1211                 goto index_ready;
1212         } else if (!tracefile_array_seq_in_file(rstream->tfa,
1213                         vstream->current_tracefile_id,
1214                         vstream->index_sent_seqcount)) {
1215                 /*
1216                  * The next index we want to send cannot be read either
1217                  * because we need to perform a rotation, or due to
1218                  * the producer having overwritten its trace file.
1219                  */
1220                 DBG("Viewer stream %" PRIu64 " rotation",
1221                                 vstream->stream->stream_handle);
1222                 ret = viewer_stream_rotate(vstream);
1223                 if (ret < 0) {
1224                         goto end;
1225                 } else if (ret == 1) {
1226                         /* EOF across entire stream. */
1227                         index->status = htobe32(LTTNG_VIEWER_INDEX_HUP);
1228                         goto hup;
1229                 }
1230                 /*
1231                  * If we have been pushed due to overwrite, it
1232                  * necessarily means there is data that can be read in
1233                  * the stream. If we rotated because we reached the end
1234                  * of a tracefile, it means the following tracefile
1235                  * needs to contain at least one index, else we would
1236                  * have already returned LTTNG_VIEWER_INDEX_RETRY to the
1237                  * viewer. The updated index_sent_seqcount needs to
1238                  * point to a readable index entry now.
1239                  *
1240                  * In the case where we "rotate" on a single file, we
1241                  * can end up in a case where the requested index is
1242                  * still unavailable.
1243                  */
1244                 if (rstream->tracefile_count == 1 &&
1245                                 !tracefile_array_seq_in_file(
1246                                         rstream->tfa,
1247                                         vstream->current_tracefile_id,
1248                                         vstream->index_sent_seqcount)) {
1249                         index->status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
1250                         goto index_ready;
1251                 }
1252                 assert(tracefile_array_seq_in_file(rstream->tfa,
1253                                 vstream->current_tracefile_id,
1254                                 vstream->index_sent_seqcount));
1255         }
1256         /* ret == 0 means successful so we continue. */
1257         ret = 0;
1258 end:
1259         return ret;
1260
1261 hup:
1262         viewer_stream_put(vstream);
1263 index_ready:
1264         return 1;
1265 }
1266
1267 /*
1268  * Send the next index for a stream.
1269  *
1270  * Return 0 on success or else a negative value.
1271  */
1272 static
1273 int viewer_get_next_index(struct relay_connection *conn)
1274 {
1275         int ret;
1276         struct lttng_viewer_get_next_index request_index;
1277         struct lttng_viewer_index viewer_index;
1278         struct ctf_packet_index packet_index;
1279         struct relay_viewer_stream *vstream = NULL;
1280         struct relay_stream *rstream = NULL;
1281         struct ctf_trace *ctf_trace = NULL;
1282         struct relay_viewer_stream *metadata_viewer_stream = NULL;
1283
1284         assert(conn);
1285
1286         DBG("Viewer get next index");
1287
1288         memset(&viewer_index, 0, sizeof(viewer_index));
1289         health_code_update();
1290
1291         ret = recv_request(conn->sock, &request_index, sizeof(request_index));
1292         if (ret < 0) {
1293                 goto end;
1294         }
1295         health_code_update();
1296
1297         vstream = viewer_stream_get_by_id(be64toh(request_index.stream_id));
1298         if (!vstream) {
1299                 DBG("Client requested index of unknown stream id %" PRIu64,
1300                                 be64toh(request_index.stream_id));
1301                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1302                 goto send_reply;
1303         }
1304
1305         /* Use back. ref. Protected by refcounts. */
1306         rstream = vstream->stream;
1307         ctf_trace = rstream->trace;
1308
1309         /* metadata_viewer_stream may be NULL. */
1310         metadata_viewer_stream =
1311                         ctf_trace_get_viewer_metadata_stream(ctf_trace);
1312
1313         pthread_mutex_lock(&rstream->lock);
1314
1315         /*
1316          * The viewer should not ask for index on metadata stream.
1317          */
1318         if (rstream->is_metadata) {
1319                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_HUP);
1320                 goto send_reply;
1321         }
1322
1323         /* Try to open an index if one is needed for that stream. */
1324         ret = try_open_index(vstream, rstream);
1325         if (ret < 0) {
1326                 if (ret == -ENOENT) {
1327                         /*
1328                          * The index is created only when the first data
1329                          * packet arrives, it might not be ready at the
1330                          * beginning of the session
1331                          */
1332                         viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
1333                 } else {
1334                         /* Unhandled error. */
1335                         viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1336                 }
1337                 goto send_reply;
1338         }
1339
1340         ret = check_index_status(vstream, rstream, ctf_trace, &viewer_index);
1341         if (ret < 0) {
1342                 goto error_put;
1343         } else if (ret == 1) {
1344                 /*
1345                  * We have no index to send and check_index_status has populated
1346                  * viewer_index's status.
1347                  */
1348                 goto send_reply;
1349         }
1350         /* At this point, ret is 0 thus we will be able to read the index. */
1351         assert(!ret);
1352
1353         /*
1354          * vstream->stream_fd may be NULL if it has been closed by
1355          * tracefile rotation, or if we are at the beginning of the
1356          * stream. We open the data stream file here to protect against
1357          * overwrite caused by tracefile rotation (in association with
1358          * unlink performed before overwrite).
1359          */
1360         if (!vstream->stream_fd) {
1361                 char fullpath[PATH_MAX];
1362
1363                 if (vstream->stream->tracefile_count > 0) {
1364                         ret = snprintf(fullpath, PATH_MAX, "%s/%s_%" PRIu64,
1365                                         vstream->path_name,
1366                                         vstream->channel_name,
1367                                         vstream->current_tracefile_id);
1368                 } else {
1369                         ret = snprintf(fullpath, PATH_MAX, "%s/%s",
1370                                         vstream->path_name,
1371                                         vstream->channel_name);
1372                 }
1373                 if (ret < 0) {
1374                         goto error_put;
1375                 }
1376                 ret = open(fullpath, O_RDONLY);
1377                 if (ret < 0) {
1378                         PERROR("Relay opening trace file");
1379                         goto error_put;
1380                 }
1381                 vstream->stream_fd = stream_fd_create(ret);
1382                 if (!vstream->stream_fd) {
1383                         if (close(ret)) {
1384                                 PERROR("close");
1385                         }
1386                         goto error_put;
1387                 }
1388         }
1389
1390         ret = check_new_streams(conn);
1391         if (ret < 0) {
1392                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1393                 goto send_reply;
1394         } else if (ret == 1) {
1395                 viewer_index.flags |= LTTNG_VIEWER_FLAG_NEW_STREAM;
1396         }
1397
1398         ret = lttng_index_file_read(vstream->index_file, &packet_index);
1399         if (ret) {
1400                 ERR("Relay error reading index file %d",
1401                                 vstream->index_file->fd);
1402                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1403                 goto send_reply;
1404         } else {
1405                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_OK);
1406                 vstream->index_sent_seqcount++;
1407         }
1408
1409         /*
1410          * Indexes are stored in big endian, no need to switch before sending.
1411          */
1412         DBG("Sending viewer index for stream %" PRIu64 " offset %" PRIu64,
1413                 rstream->stream_handle,
1414                 be64toh(packet_index.offset));
1415         viewer_index.offset = packet_index.offset;
1416         viewer_index.packet_size = packet_index.packet_size;
1417         viewer_index.content_size = packet_index.content_size;
1418         viewer_index.timestamp_begin = packet_index.timestamp_begin;
1419         viewer_index.timestamp_end = packet_index.timestamp_end;
1420         viewer_index.events_discarded = packet_index.events_discarded;
1421         viewer_index.stream_id = packet_index.stream_id;
1422
1423 send_reply:
1424         if (rstream) {
1425                 pthread_mutex_unlock(&rstream->lock);
1426         }
1427
1428         if (metadata_viewer_stream) {
1429                 pthread_mutex_lock(&metadata_viewer_stream->stream->lock);
1430                 DBG("get next index metadata check: recv %" PRIu64
1431                                 " sent %" PRIu64,
1432                         metadata_viewer_stream->stream->metadata_received,
1433                         metadata_viewer_stream->metadata_sent);
1434                 if (!metadata_viewer_stream->stream->metadata_received ||
1435                                 metadata_viewer_stream->stream->metadata_received >
1436                                         metadata_viewer_stream->metadata_sent) {
1437                         viewer_index.flags |= LTTNG_VIEWER_FLAG_NEW_METADATA;
1438                 }
1439                 pthread_mutex_unlock(&metadata_viewer_stream->stream->lock);
1440         }
1441
1442         viewer_index.flags = htobe32(viewer_index.flags);
1443         health_code_update();
1444
1445         ret = send_response(conn->sock, &viewer_index, sizeof(viewer_index));
1446         if (ret < 0) {
1447                 goto end;
1448         }
1449         health_code_update();
1450
1451         if (vstream) {
1452                 DBG("Index %" PRIu64 " for stream %" PRIu64 " sent",
1453                                 vstream->index_sent_seqcount,
1454                                 vstream->stream->stream_handle);
1455         }
1456 end:
1457         if (metadata_viewer_stream) {
1458                 viewer_stream_put(metadata_viewer_stream);
1459         }
1460         if (vstream) {
1461                 viewer_stream_put(vstream);
1462         }
1463         return ret;
1464
1465 error_put:
1466         pthread_mutex_unlock(&rstream->lock);
1467         if (metadata_viewer_stream) {
1468                 viewer_stream_put(metadata_viewer_stream);
1469         }
1470         viewer_stream_put(vstream);
1471         return ret;
1472 }
1473
1474 /*
1475  * Send the next index for a stream
1476  *
1477  * Return 0 on success or else a negative value.
1478  */
1479 static
1480 int viewer_get_packet(struct relay_connection *conn)
1481 {
1482         int ret, send_data = 0;
1483         char *data = NULL;
1484         uint32_t len = 0;
1485         ssize_t read_len;
1486         struct lttng_viewer_get_packet get_packet_info;
1487         struct lttng_viewer_trace_packet reply;
1488         struct relay_viewer_stream *vstream = NULL;
1489
1490         DBG2("Relay get data packet");
1491
1492         health_code_update();
1493
1494         ret = recv_request(conn->sock, &get_packet_info,
1495                         sizeof(get_packet_info));
1496         if (ret < 0) {
1497                 goto end;
1498         }
1499         health_code_update();
1500
1501         /* From this point on, the error label can be reached. */
1502         memset(&reply, 0, sizeof(reply));
1503
1504         vstream = viewer_stream_get_by_id(be64toh(get_packet_info.stream_id));
1505         if (!vstream) {
1506                 DBG("Client requested packet of unknown stream id %" PRIu64,
1507                                 be64toh(get_packet_info.stream_id));
1508                 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_ERR);
1509                 goto send_reply_nolock;
1510         }
1511
1512         pthread_mutex_lock(&vstream->stream->lock);
1513
1514         len = be32toh(get_packet_info.len);
1515         data = zmalloc(len);
1516         if (!data) {
1517                 PERROR("relay data zmalloc");
1518                 goto error;
1519         }
1520
1521         ret = lseek(vstream->stream_fd->fd, be64toh(get_packet_info.offset),
1522                         SEEK_SET);
1523         if (ret < 0) {
1524                 PERROR("lseek fd %d to offset %" PRIu64, vstream->stream_fd->fd,
1525                         be64toh(get_packet_info.offset));
1526                 goto error;
1527         }
1528         read_len = lttng_read(vstream->stream_fd->fd, data, len);
1529         if (read_len < len) {
1530                 PERROR("Relay reading trace file, fd: %d, offset: %" PRIu64,
1531                                 vstream->stream_fd->fd,
1532                                 be64toh(get_packet_info.offset));
1533                 goto error;
1534         }
1535         reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_OK);
1536         reply.len = htobe32(len);
1537         send_data = 1;
1538         goto send_reply;
1539
1540 error:
1541         reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_ERR);
1542
1543 send_reply:
1544         if (vstream) {
1545                 pthread_mutex_unlock(&vstream->stream->lock);
1546         }
1547 send_reply_nolock:
1548         reply.flags = htobe32(reply.flags);
1549
1550         health_code_update();
1551
1552         ret = send_response(conn->sock, &reply, sizeof(reply));
1553         if (ret < 0) {
1554                 goto end_free;
1555         }
1556         health_code_update();
1557
1558         if (send_data) {
1559                 health_code_update();
1560                 ret = send_response(conn->sock, data, len);
1561                 if (ret < 0) {
1562                         goto end_free;
1563                 }
1564                 health_code_update();
1565         }
1566
1567         DBG("Sent %u bytes for stream %" PRIu64, len,
1568                         be64toh(get_packet_info.stream_id));
1569
1570 end_free:
1571         free(data);
1572 end:
1573         if (vstream) {
1574                 viewer_stream_put(vstream);
1575         }
1576         return ret;
1577 }
1578
1579 /*
1580  * Send the session's metadata
1581  *
1582  * Return 0 on success else a negative value.
1583  */
1584 static
1585 int viewer_get_metadata(struct relay_connection *conn)
1586 {
1587         int ret = 0;
1588         ssize_t read_len;
1589         uint64_t len = 0;
1590         char *data = NULL;
1591         struct lttng_viewer_get_metadata request;
1592         struct lttng_viewer_metadata_packet reply;
1593         struct relay_viewer_stream *vstream = NULL;
1594
1595         assert(conn);
1596
1597         DBG("Relay get metadata");
1598
1599         health_code_update();
1600
1601         ret = recv_request(conn->sock, &request, sizeof(request));
1602         if (ret < 0) {
1603                 goto end;
1604         }
1605         health_code_update();
1606
1607         memset(&reply, 0, sizeof(reply));
1608
1609         vstream = viewer_stream_get_by_id(be64toh(request.stream_id));
1610         if (!vstream) {
1611                 /*
1612                  * The metadata stream can be closed by a CLOSE command
1613                  * just before we attach. It can also be closed by
1614                  * per-pid tracing during tracing. Therefore, it is
1615                  * possible that we cannot find this viewer stream.
1616                  * Reply back to the client with an error if we cannot
1617                  * find it.
1618                  */
1619                 DBG("Client requested metadata of unknown stream id %" PRIu64,
1620                                 be64toh(request.stream_id));
1621                 reply.status = htobe32(LTTNG_VIEWER_METADATA_ERR);
1622                 goto send_reply;
1623         }
1624         pthread_mutex_lock(&vstream->stream->lock);
1625         if (!vstream->stream->is_metadata) {
1626                 ERR("Invalid metadata stream");
1627                 goto error;
1628         }
1629
1630         assert(vstream->metadata_sent <= vstream->stream->metadata_received);
1631
1632         len = vstream->stream->metadata_received - vstream->metadata_sent;
1633         if (len == 0) {
1634                 reply.status = htobe32(LTTNG_VIEWER_NO_NEW_METADATA);
1635                 goto send_reply;
1636         }
1637
1638         /* first time, we open the metadata file */
1639         if (!vstream->stream_fd) {
1640                 char fullpath[PATH_MAX];
1641
1642                 ret = snprintf(fullpath, PATH_MAX, "%s/%s", vstream->path_name,
1643                                 vstream->channel_name);
1644                 if (ret < 0) {
1645                         goto error;
1646                 }
1647                 ret = open(fullpath, O_RDONLY);
1648                 if (ret < 0) {
1649                         PERROR("Relay opening metadata file");
1650                         goto error;
1651                 }
1652                 vstream->stream_fd = stream_fd_create(ret);
1653                 if (!vstream->stream_fd) {
1654                         if (close(ret)) {
1655                                 PERROR("close");
1656                         }
1657                         goto error;
1658                 }
1659         }
1660
1661         reply.len = htobe64(len);
1662         data = zmalloc(len);
1663         if (!data) {
1664                 PERROR("viewer metadata zmalloc");
1665                 goto error;
1666         }
1667
1668         read_len = lttng_read(vstream->stream_fd->fd, data, len);
1669         if (read_len < len) {
1670                 PERROR("Relay reading metadata file");
1671                 goto error;
1672         }
1673         vstream->metadata_sent += read_len;
1674         if (vstream->metadata_sent == vstream->stream->metadata_received
1675                         && vstream->stream->closed) {
1676                 /* Release ownership for the viewer metadata stream. */
1677                 viewer_stream_put(vstream);
1678         }
1679
1680         reply.status = htobe32(LTTNG_VIEWER_METADATA_OK);
1681
1682         goto send_reply;
1683
1684 error:
1685         reply.status = htobe32(LTTNG_VIEWER_METADATA_ERR);
1686
1687 send_reply:
1688         health_code_update();
1689         if (vstream) {
1690                 pthread_mutex_unlock(&vstream->stream->lock);
1691         }
1692         ret = send_response(conn->sock, &reply, sizeof(reply));
1693         if (ret < 0) {
1694                 goto end_free;
1695         }
1696         health_code_update();
1697
1698         if (len > 0) {
1699                 ret = send_response(conn->sock, data, len);
1700                 if (ret < 0) {
1701                         goto end_free;
1702                 }
1703         }
1704
1705         DBG("Sent %" PRIu64 " bytes of metadata for stream %" PRIu64, len,
1706                         be64toh(request.stream_id));
1707
1708         DBG("Metadata sent");
1709
1710 end_free:
1711         free(data);
1712 end:
1713         if (vstream) {
1714                 viewer_stream_put(vstream);
1715         }
1716         return ret;
1717 }
1718
1719 /*
1720  * Create a viewer session.
1721  *
1722  * Return 0 on success or else a negative value.
1723  */
1724 static
1725 int viewer_create_session(struct relay_connection *conn)
1726 {
1727         int ret;
1728         struct lttng_viewer_create_session_response resp;
1729
1730         DBG("Viewer create session received");
1731
1732         memset(&resp, 0, sizeof(resp));
1733         resp.status = htobe32(LTTNG_VIEWER_CREATE_SESSION_OK);
1734         conn->viewer_session = viewer_session_create();
1735         if (!conn->viewer_session) {
1736                 ERR("Allocation viewer session");
1737                 resp.status = htobe32(LTTNG_VIEWER_CREATE_SESSION_ERR);
1738                 goto send_reply;
1739         }
1740
1741 send_reply:
1742         health_code_update();
1743         ret = send_response(conn->sock, &resp, sizeof(resp));
1744         if (ret < 0) {
1745                 goto end;
1746         }
1747         health_code_update();
1748         ret = 0;
1749
1750 end:
1751         return ret;
1752 }
1753
1754 /*
1755  * Detach a viewer session.
1756  *
1757  * Return 0 on success or else a negative value.
1758  */
1759 static
1760 int viewer_detach_session(struct relay_connection *conn)
1761 {
1762         int ret;
1763         struct lttng_viewer_detach_session_response response;
1764         struct lttng_viewer_detach_session_request request;
1765         struct relay_session *session = NULL;
1766         uint64_t viewer_session_to_close;
1767
1768         DBG("Viewer detach session received");
1769
1770         assert(conn);
1771
1772         health_code_update();
1773
1774         /* Receive the request from the connected client. */
1775         ret = recv_request(conn->sock, &request, sizeof(request));
1776         if (ret < 0) {
1777                 goto end;
1778         }
1779         viewer_session_to_close = be64toh(request.session_id);
1780
1781         if (!conn->viewer_session) {
1782                 DBG("Client trying to detach before creating a live viewer session");
1783                 response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR);
1784                 goto send_reply;
1785         }
1786
1787         health_code_update();
1788
1789         memset(&response, 0, sizeof(response));
1790         DBG("Detaching from session ID %" PRIu64, viewer_session_to_close);
1791
1792         session = session_get_by_id(be64toh(request.session_id));
1793         if (!session) {
1794                 DBG("Relay session %" PRIu64 " not found",
1795                                 be64toh(request.session_id));
1796                 response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_UNK);
1797                 goto send_reply;
1798         }
1799
1800         ret = viewer_session_is_attached(conn->viewer_session, session);
1801         if (ret != 1) {
1802                 DBG("Not attached to this session");
1803                 response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR);
1804                 goto send_reply_put;
1805         }
1806
1807         viewer_session_close_one_session(conn->viewer_session, session);
1808         response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_OK);
1809         DBG("Session %" PRIu64 " detached.", viewer_session_to_close);
1810
1811 send_reply_put:
1812         session_put(session);
1813
1814 send_reply:
1815         health_code_update();
1816         ret = send_response(conn->sock, &response, sizeof(response));
1817         if (ret < 0) {
1818                 goto end;
1819         }
1820         health_code_update();
1821         ret = 0;
1822
1823 end:
1824         return ret;
1825 }
1826
1827 /*
1828  * live_relay_unknown_command: send -1 if received unknown command
1829  */
1830 static
1831 void live_relay_unknown_command(struct relay_connection *conn)
1832 {
1833         struct lttcomm_relayd_generic_reply reply;
1834
1835         memset(&reply, 0, sizeof(reply));
1836         reply.ret_code = htobe32(LTTNG_ERR_UNK);
1837         (void) send_response(conn->sock, &reply, sizeof(reply));
1838 }
1839
1840 /*
1841  * Process the commands received on the control socket
1842  */
1843 static
1844 int process_control(struct lttng_viewer_cmd *recv_hdr,
1845                 struct relay_connection *conn)
1846 {
1847         int ret = 0;
1848         uint32_t msg_value;
1849
1850         msg_value = be32toh(recv_hdr->cmd);
1851
1852         /*
1853          * Make sure we've done the version check before any command other then a
1854          * new client connection.
1855          */
1856         if (msg_value != LTTNG_VIEWER_CONNECT && !conn->version_check_done) {
1857                 ERR("Viewer conn value %" PRIu32 " before version check", msg_value);
1858                 ret = -1;
1859                 goto end;
1860         }
1861
1862         switch (msg_value) {
1863         case LTTNG_VIEWER_CONNECT:
1864                 ret = viewer_connect(conn);
1865                 break;
1866         case LTTNG_VIEWER_LIST_SESSIONS:
1867                 ret = viewer_list_sessions(conn);
1868                 break;
1869         case LTTNG_VIEWER_ATTACH_SESSION:
1870                 ret = viewer_attach_session(conn);
1871                 break;
1872         case LTTNG_VIEWER_GET_NEXT_INDEX:
1873                 ret = viewer_get_next_index(conn);
1874                 break;
1875         case LTTNG_VIEWER_GET_PACKET:
1876                 ret = viewer_get_packet(conn);
1877                 break;
1878         case LTTNG_VIEWER_GET_METADATA:
1879                 ret = viewer_get_metadata(conn);
1880                 break;
1881         case LTTNG_VIEWER_GET_NEW_STREAMS:
1882                 ret = viewer_get_new_streams(conn);
1883                 break;
1884         case LTTNG_VIEWER_CREATE_SESSION:
1885                 ret = viewer_create_session(conn);
1886                 break;
1887         case LTTNG_VIEWER_DETACH_SESSION:
1888                 ret = viewer_detach_session(conn);
1889                 break;
1890         default:
1891                 ERR("Received unknown viewer command (%u)",
1892                                 be32toh(recv_hdr->cmd));
1893                 live_relay_unknown_command(conn);
1894                 ret = -1;
1895                 goto end;
1896         }
1897
1898 end:
1899         return ret;
1900 }
1901
1902 static
1903 void cleanup_connection_pollfd(struct lttng_poll_event *events, int pollfd)
1904 {
1905         int ret;
1906
1907         (void) lttng_poll_del(events, pollfd);
1908
1909         ret = close(pollfd);
1910         if (ret < 0) {
1911                 ERR("Closing pollfd %d", pollfd);
1912         }
1913 }
1914
1915 /*
1916  * This thread does the actual work
1917  */
1918 static
1919 void *thread_worker(void *data)
1920 {
1921         int ret, err = -1;
1922         uint32_t nb_fd;
1923         struct lttng_poll_event events;
1924         struct lttng_ht *viewer_connections_ht;
1925         struct lttng_ht_iter iter;
1926         struct lttng_viewer_cmd recv_hdr;
1927         struct relay_connection *destroy_conn;
1928
1929         DBG("[thread] Live viewer relay worker started");
1930
1931         rcu_register_thread();
1932
1933         health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_WORKER);
1934
1935         if (testpoint(relayd_thread_live_worker)) {
1936                 goto error_testpoint;
1937         }
1938
1939         /* table of connections indexed on socket */
1940         viewer_connections_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1941         if (!viewer_connections_ht) {
1942                 goto viewer_connections_ht_error;
1943         }
1944
1945         ret = create_thread_poll_set(&events, 2);
1946         if (ret < 0) {
1947                 goto error_poll_create;
1948         }
1949
1950         ret = lttng_poll_add(&events, live_conn_pipe[0], LPOLLIN | LPOLLRDHUP);
1951         if (ret < 0) {
1952                 goto error;
1953         }
1954
1955 restart:
1956         while (1) {
1957                 int i;
1958
1959                 health_code_update();
1960
1961                 /* Infinite blocking call, waiting for transmission */
1962                 DBG3("Relayd live viewer worker thread polling...");
1963                 health_poll_entry();
1964                 ret = lttng_poll_wait(&events, -1);
1965                 health_poll_exit();
1966                 if (ret < 0) {
1967                         /*
1968                          * Restart interrupted system call.
1969                          */
1970                         if (errno == EINTR) {
1971                                 goto restart;
1972                         }
1973                         goto error;
1974                 }
1975
1976                 nb_fd = ret;
1977
1978                 /*
1979                  * Process control. The control connection is prioritised so we don't
1980                  * starve it with high throughput tracing data on the data
1981                  * connection.
1982                  */
1983                 for (i = 0; i < nb_fd; i++) {
1984                         /* Fetch once the poll data */
1985                         uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1986                         int pollfd = LTTNG_POLL_GETFD(&events, i);
1987
1988                         health_code_update();
1989
1990                         if (!revents) {
1991                                 /* No activity for this FD (poll implementation). */
1992                                 continue;
1993                         }
1994
1995                         /* Thread quit pipe has been closed. Killing thread. */
1996                         ret = check_thread_quit_pipe(pollfd, revents);
1997                         if (ret) {
1998                                 err = 0;
1999                                 goto exit;
2000                         }
2001
2002                         /* Inspect the relay conn pipe for new connection. */
2003                         if (pollfd == live_conn_pipe[0]) {
2004                                 if (revents & LPOLLIN) {
2005                                         struct relay_connection *conn;
2006
2007                                         ret = lttng_read(live_conn_pipe[0],
2008                                                         &conn, sizeof(conn));
2009                                         if (ret < 0) {
2010                                                 goto error;
2011                                         }
2012                                         lttng_poll_add(&events, conn->sock->fd,
2013                                                         LPOLLIN | LPOLLRDHUP);
2014                                         connection_ht_add(viewer_connections_ht, conn);
2015                                         DBG("Connection socket %d added to poll", conn->sock->fd);
2016                                 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2017                                         ERR("Relay live pipe error");
2018                                         goto error;
2019                                 } else {
2020                                         ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2021                                         goto error;
2022                                 }
2023                         } else {
2024                                 /* Connection activity. */
2025                                 struct relay_connection *conn;
2026
2027                                 conn = connection_get_by_sock(viewer_connections_ht, pollfd);
2028                                 if (!conn) {
2029                                         continue;
2030                                 }
2031
2032                                 if (revents & LPOLLIN) {
2033                                         ret = conn->sock->ops->recvmsg(conn->sock, &recv_hdr,
2034                                                         sizeof(recv_hdr), 0);
2035                                         if (ret <= 0) {
2036                                                 /* Connection closed. */
2037                                                 cleanup_connection_pollfd(&events, pollfd);
2038                                                 /* Put "create" ownership reference. */
2039                                                 connection_put(conn);
2040                                                 DBG("Viewer control conn closed with %d", pollfd);
2041                                         } else {
2042                                                 ret = process_control(&recv_hdr, conn);
2043                                                 if (ret < 0) {
2044                                                         /* Clear the session on error. */
2045                                                         cleanup_connection_pollfd(&events, pollfd);
2046                                                         /* Put "create" ownership reference. */
2047                                                         connection_put(conn);
2048                                                         DBG("Viewer connection closed with %d", pollfd);
2049                                                 }
2050                                         }
2051                                 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2052                                         cleanup_connection_pollfd(&events, pollfd);
2053                                         /* Put "create" ownership reference. */
2054                                         connection_put(conn);
2055                                 } else {
2056                                         ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2057                                         connection_put(conn);
2058                                         goto error;
2059                                 }
2060                                 /* Put local "get_by_sock" reference. */
2061                                 connection_put(conn);
2062                         }
2063                 }
2064         }
2065
2066 exit:
2067 error:
2068         lttng_poll_clean(&events);
2069
2070         /* Cleanup reamaining connection object. */
2071         rcu_read_lock();
2072         cds_lfht_for_each_entry(viewer_connections_ht->ht, &iter.iter,
2073                         destroy_conn,
2074                         sock_n.node) {
2075                 health_code_update();
2076                 connection_put(destroy_conn);
2077         }
2078         rcu_read_unlock();
2079 error_poll_create:
2080         lttng_ht_destroy(viewer_connections_ht);
2081 viewer_connections_ht_error:
2082         /* Close relay conn pipes */
2083         utils_close_pipe(live_conn_pipe);
2084         if (err) {
2085                 DBG("Viewer worker thread exited with error");
2086         }
2087         DBG("Viewer worker thread cleanup complete");
2088 error_testpoint:
2089         if (err) {
2090                 health_error();
2091                 ERR("Health error occurred in %s", __func__);
2092         }
2093         health_unregister(health_relayd);
2094         if (lttng_relay_stop_threads()) {
2095                 ERR("Error stopping threads");
2096         }
2097         rcu_unregister_thread();
2098         return NULL;
2099 }
2100
2101 /*
2102  * Create the relay command pipe to wake thread_manage_apps.
2103  * Closed in cleanup().
2104  */
2105 static int create_conn_pipe(void)
2106 {
2107         return utils_create_pipe_cloexec(live_conn_pipe);
2108 }
2109
2110 int relayd_live_join(void)
2111 {
2112         int ret, retval = 0;
2113         void *status;
2114
2115         ret = pthread_join(live_listener_thread, &status);
2116         if (ret) {
2117                 errno = ret;
2118                 PERROR("pthread_join live listener");
2119                 retval = -1;
2120         }
2121
2122         ret = pthread_join(live_worker_thread, &status);
2123         if (ret) {
2124                 errno = ret;
2125                 PERROR("pthread_join live worker");
2126                 retval = -1;
2127         }
2128
2129         ret = pthread_join(live_dispatcher_thread, &status);
2130         if (ret) {
2131                 errno = ret;
2132                 PERROR("pthread_join live dispatcher");
2133                 retval = -1;
2134         }
2135
2136         cleanup_relayd_live();
2137
2138         return retval;
2139 }
2140
2141 /*
2142  * main
2143  */
2144 int relayd_live_create(struct lttng_uri *uri)
2145 {
2146         int ret = 0, retval = 0;
2147         void *status;
2148         int is_root;
2149
2150         if (!uri) {
2151                 retval = -1;
2152                 goto exit_init_data;
2153         }
2154         live_uri = uri;
2155
2156         /* Check if daemon is UID = 0 */
2157         is_root = !getuid();
2158
2159         if (!is_root) {
2160                 if (live_uri->port < 1024) {
2161                         ERR("Need to be root to use ports < 1024");
2162                         retval = -1;
2163                         goto exit_init_data;
2164                 }
2165         }
2166
2167         /* Setup the thread apps communication pipe. */
2168         if (create_conn_pipe()) {
2169                 retval = -1;
2170                 goto exit_init_data;
2171         }
2172
2173         /* Init relay command queue. */
2174         cds_wfcq_init(&viewer_conn_queue.head, &viewer_conn_queue.tail);
2175
2176         /* Set up max poll set size */
2177         if (lttng_poll_set_max_size()) {
2178                 retval = -1;
2179                 goto exit_init_data;
2180         }
2181
2182         /* Setup the dispatcher thread */
2183         ret = pthread_create(&live_dispatcher_thread, default_pthread_attr(),
2184                         thread_dispatcher, (void *) NULL);
2185         if (ret) {
2186                 errno = ret;
2187                 PERROR("pthread_create viewer dispatcher");
2188                 retval = -1;
2189                 goto exit_dispatcher_thread;
2190         }
2191
2192         /* Setup the worker thread */
2193         ret = pthread_create(&live_worker_thread, default_pthread_attr(),
2194                         thread_worker, NULL);
2195         if (ret) {
2196                 errno = ret;
2197                 PERROR("pthread_create viewer worker");
2198                 retval = -1;
2199                 goto exit_worker_thread;
2200         }
2201
2202         /* Setup the listener thread */
2203         ret = pthread_create(&live_listener_thread, default_pthread_attr(),
2204                         thread_listener, (void *) NULL);
2205         if (ret) {
2206                 errno = ret;
2207                 PERROR("pthread_create viewer listener");
2208                 retval = -1;
2209                 goto exit_listener_thread;
2210         }
2211
2212         /*
2213          * All OK, started all threads.
2214          */
2215         return retval;
2216
2217         /*
2218          * Join on the live_listener_thread should anything be added after
2219          * the live_listener thread's creation.
2220          */
2221
2222 exit_listener_thread:
2223
2224         ret = pthread_join(live_worker_thread, &status);
2225         if (ret) {
2226                 errno = ret;
2227                 PERROR("pthread_join live worker");
2228                 retval = -1;
2229         }
2230 exit_worker_thread:
2231
2232         ret = pthread_join(live_dispatcher_thread, &status);
2233         if (ret) {
2234                 errno = ret;
2235                 PERROR("pthread_join live dispatcher");
2236                 retval = -1;
2237         }
2238 exit_dispatcher_thread:
2239
2240 exit_init_data:
2241         cleanup_relayd_live();
2242
2243         return retval;
2244 }