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