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                                 viewer_stream_get(vstream);
 343                         } else {
 344                                 if (!vstream->sent_flag && nb_unsent) {
 345                                         /* Update number of unsent stream counter. */
 346                                         (*nb_unsent)++;
 347                                 }
 348                         }
 349                         /* Update number of total stream counter. */
 350                         if (nb_total) {
 351                                 if (stream->is_metadata) {
 352                                         if (!stream->closed ||
 353                                                         stream->metadata_received > vstream->metadata_sent) {
 354                                                 (*nb_total)++;
 355                                         }
 356                                 } else {
 357                                         if (!stream->closed ||
 358                                                 !(((int64_t) (stream->prev_seq - stream->last_net_seq_num)) >= 0)) {
 359
 360                                                 (*nb_total)++;
 361                                         }
 362                                 }
 363                         }
 364                         /* Put local reference. */
 365                         viewer_stream_put(vstream);
 366                 next:
 367                         stream_put(stream);
 368                 }
 369                 ctf_trace_put(ctf_trace);
 370         }
 371
 372         ret = 0;
 373
 374 error_unlock:
 375         rcu_read_unlock();
 376         pthread_mutex_unlock(&session->lock);
 377         return ret;
 378 }
 379
 380 int relayd_live_stop(void)
 381 {
 382         /* Stop dispatch thread */
 383         CMM_STORE_SHARED(live_dispatch_thread_exit, 1);
 384         futex_nto1_wake(&viewer_conn_queue.futex);
 385         return 0;
 386 }
 387
 388 /*
 389  * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
 390  */
 391 static
 392 int create_thread_poll_set(struct lttng_poll_event *events, int size)
 393 {
 394         int ret;
 395
 396         if (events == NULL || size == 0) {
 397                 ret = -1;
 398                 goto error;
 399         }
 400
 401         ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
 402         if (ret < 0) {
 403                 goto error;
 404         }
 405
 406         /* Add quit pipe */
 407         ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN | LPOLLERR);
 408         if (ret < 0) {
 409                 goto error;
 410         }
 411
 412         return 0;
 413
 414 error:
 415         return ret;
 416 }
 417
 418 /*
 419  * Check if the thread quit pipe was triggered.
 420  *
 421  * Return 1 if it was triggered else 0;
 422  */
 423 static
 424 int check_thread_quit_pipe(int fd, uint32_t events)
 425 {
 426         if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
 427                 return 1;
 428         }
 429
 430         return 0;
 431 }
 432
 433 /*
 434  * Create and init socket from uri.
 435  */
 436 static
 437 struct lttcomm_sock *init_socket(struct lttng_uri *uri)
 438 {
 439         int ret;
 440         struct lttcomm_sock *sock = NULL;
 441
 442         sock = lttcomm_alloc_sock_from_uri(uri);
 443         if (sock == NULL) {
 444                 ERR("Allocating socket");
 445                 goto error;
 446         }
 447
 448         ret = lttcomm_create_sock(sock);
 449         if (ret < 0) {
 450                 goto error;
 451         }
 452         DBG("Listening on sock %d for live", sock->fd);
 453
 454         ret = sock->ops->bind(sock);
 455         if (ret < 0) {
 456                 goto error;
 457         }
 458
 459         ret = sock->ops->listen(sock, -1);
 460         if (ret < 0) {
 461                 goto error;
 462
 463         }
 464
 465         return sock;
 466
 467 error:
 468         if (sock) {
 469                 lttcomm_destroy_sock(sock);
 470         }
 471         return NULL;
 472 }
 473
 474 /*
 475  * This thread manages the listening for new connections on the network
 476  */
 477 static
 478 void *thread_listener(void *data)
 479 {
 480         int i, ret, pollfd, err = -1;
 481         uint32_t revents, nb_fd;
 482         struct lttng_poll_event events;
 483         struct lttcomm_sock *live_control_sock;
 484
 485         DBG("[thread] Relay live listener started");
 486
 487         health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_LISTENER);
 488
 489         health_code_update();
 490
 491         live_control_sock = init_socket(live_uri);
 492         if (!live_control_sock) {
 493                 goto error_sock_control;
 494         }
 495
 496         /* Pass 2 as size here for the thread quit pipe and control sockets. */
 497         ret = create_thread_poll_set(&events, 2);
 498         if (ret < 0) {
 499                 goto error_create_poll;
 500         }
 501
 502         /* Add the control socket */
 503         ret = lttng_poll_add(&events, live_control_sock->fd, LPOLLIN | LPOLLRDHUP);
 504         if (ret < 0) {
 505                 goto error_poll_add;
 506         }
 507
 508         lttng_relay_notify_ready();
 509
 510         if (testpoint(relayd_thread_live_listener)) {
 511                 goto error_testpoint;
 512         }
 513
 514         while (1) {
 515                 health_code_update();
 516
 517                 DBG("Listener accepting live viewers connections");
 518
 519 restart:
 520                 health_poll_entry();
 521                 ret = lttng_poll_wait(&events, -1);
 522                 health_poll_exit();
 523                 if (ret < 0) {
 524                         /*
 525                          * Restart interrupted system call.
 526                          */
 527                         if (errno == EINTR) {
 528                                 goto restart;
 529                         }
 530                         goto error;
 531                 }
 532                 nb_fd = ret;
 533
 534                 DBG("Relay new viewer connection received");
 535                 for (i = 0; i < nb_fd; i++) {
 536                         health_code_update();
 537
 538                         /* Fetch once the poll data */
 539                         revents = LTTNG_POLL_GETEV(&events, i);
 540                         pollfd = LTTNG_POLL_GETFD(&events, i);
 541
 542                         if (!revents) {
 543                                 /* No activity for this FD (poll implementation). */
 544                                 continue;
 545                         }
 546
 547                         /* Thread quit pipe has been closed. Killing thread. */
 548                         ret = check_thread_quit_pipe(pollfd, revents);
 549                         if (ret) {
 550                                 err = 0;
 551                                 goto exit;
 552                         }
 553
 554                         if (revents & LPOLLIN) {
 555                                 /*
 556                                  * A new connection is requested, therefore a
 557                                  * viewer connection is allocated in this
 558                                  * thread, enqueued to a global queue and
 559                                  * dequeued (and freed) in the worker thread.
 560                                  */
 561                                 int val = 1;
 562                                 struct relay_connection *new_conn;
 563                                 struct lttcomm_sock *newsock;
 564
 565                                 newsock = live_control_sock->ops->accept(live_control_sock);
 566                                 if (!newsock) {
 567                                         PERROR("accepting control sock");
 568                                         goto error;
 569                                 }
 570                                 DBG("Relay viewer connection accepted socket %d", newsock->fd);
 571
 572                                 ret = setsockopt(newsock->fd, SOL_SOCKET, SO_REUSEADDR, &val,
 573                                                 sizeof(val));
 574                                 if (ret < 0) {
 575                                         PERROR("setsockopt inet");
 576                                         lttcomm_destroy_sock(newsock);
 577                                         goto error;
 578                                 }
 579                                 new_conn = connection_create(newsock, RELAY_CONNECTION_UNKNOWN);
 580                                 if (!new_conn) {
 581                                         lttcomm_destroy_sock(newsock);
 582                                         goto error;
 583                                 }
 584                                 /* Ownership assumed by the connection. */
 585                                 newsock = NULL;
 586
 587                                 /* Enqueue request for the dispatcher thread. */
 588                                 cds_wfcq_enqueue(&viewer_conn_queue.head, &viewer_conn_queue.tail,
 589                                                  &new_conn->qnode);
 590
 591                                 /*
 592                                  * Wake the dispatch queue futex.
 593                                  * Implicit memory barrier with the
 594                                  * exchange in cds_wfcq_enqueue.
 595                                  */
 596                                 futex_nto1_wake(&viewer_conn_queue.futex);
 597                         } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
 598                                 ERR("socket poll error");
 599                                 goto error;
 600                         } else {
 601                                 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
 602                                 goto error;
 603                         }
 604                 }
 605         }
 606
 607 exit:
 608 error:
 609 error_poll_add:
 610 error_testpoint:
 611         lttng_poll_clean(&events);
 612 error_create_poll:
 613         if (live_control_sock->fd >= 0) {
 614                 ret = live_control_sock->ops->close(live_control_sock);
 615                 if (ret) {
 616                         PERROR("close");
 617                 }
 618         }
 619         lttcomm_destroy_sock(live_control_sock);
 620 error_sock_control:
 621         if (err) {
 622                 health_error();
 623                 DBG("Live viewer listener thread exited with error");
 624         }
 625         health_unregister(health_relayd);
 626         DBG("Live viewer listener thread cleanup complete");
 627         if (lttng_relay_stop_threads()) {
 628                 ERR("Error stopping threads");
 629         }
 630         return NULL;
 631 }
 632
 633 /*
 634  * This thread manages the dispatching of the requests to worker threads
 635  */
 636 static
 637 void *thread_dispatcher(void *data)
 638 {
 639         int err = -1;
 640         ssize_t ret;
 641         struct cds_wfcq_node *node;
 642         struct relay_connection *conn = NULL;
 643
 644         DBG("[thread] Live viewer relay dispatcher started");
 645
 646         health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_DISPATCHER);
 647
 648         if (testpoint(relayd_thread_live_dispatcher)) {
 649                 goto error_testpoint;
 650         }
 651
 652         health_code_update();
 653
 654         while (!CMM_LOAD_SHARED(live_dispatch_thread_exit)) {
 655                 health_code_update();
 656
 657                 /* Atomically prepare the queue futex */
 658                 futex_nto1_prepare(&viewer_conn_queue.futex);
 659
 660                 do {
 661                         health_code_update();
 662
 663                         /* Dequeue commands */
 664                         node = cds_wfcq_dequeue_blocking(&viewer_conn_queue.head,
 665                                                          &viewer_conn_queue.tail);
 666                         if (node == NULL) {
 667                                 DBG("Woken up but nothing in the live-viewer "
 668                                                 "relay command queue");
 669                                 /* Continue thread execution */
 670                                 break;
 671                         }
 672                         conn = caa_container_of(node, struct relay_connection, qnode);
 673                         DBG("Dispatching viewer request waiting on sock %d",
 674                                         conn->sock->fd);
 675
 676                         /*
 677                          * Inform worker thread of the new request. This
 678                          * call is blocking so we can be assured that
 679                          * the data will be read at some point in time
 680                          * or wait to the end of the world :)
 681                          */
 682                         ret = lttng_write(live_conn_pipe[1], &conn, sizeof(conn));
 683                         if (ret < 0) {
 684                                 PERROR("write conn pipe");
 685                                 connection_put(conn);
 686                                 goto error;
 687                         }
 688                 } while (node != NULL);
 689
 690                 /* Futex wait on queue. Blocking call on futex() */
 691                 health_poll_entry();
 692                 futex_nto1_wait(&viewer_conn_queue.futex);
 693                 health_poll_exit();
 694         }
 695
 696         /* Normal exit, no error */
 697         err = 0;
 698
 699 error:
 700 error_testpoint:
 701         if (err) {
 702                 health_error();
 703                 ERR("Health error occurred in %s", __func__);
 704         }
 705         health_unregister(health_relayd);
 706         DBG("Live viewer dispatch thread dying");
 707         if (lttng_relay_stop_threads()) {
 708                 ERR("Error stopping threads");
 709         }
 710         return NULL;
 711 }
 712
 713 /*
 714  * Establish connection with the viewer and check the versions.
 715  *
 716  * Return 0 on success or else negative value.
 717  */
 718 static
 719 int viewer_connect(struct relay_connection *conn)
 720 {
 721         int ret;
 722         struct lttng_viewer_connect reply, msg;
 723
 724         conn->version_check_done = 1;
 725
 726         health_code_update();
 727
 728         DBG("Viewer is establishing a connection to the relayd.");
 729
 730         ret = recv_request(conn->sock, &msg, sizeof(msg));
 731         if (ret < 0) {
 732                 goto end;
 733         }
 734
 735         health_code_update();
 736
 737         memset(&reply, 0, sizeof(reply));
 738         reply.major = RELAYD_VERSION_COMM_MAJOR;
 739         reply.minor = RELAYD_VERSION_COMM_MINOR;
 740
 741         /* Major versions must be the same */
 742         if (reply.major != be32toh(msg.major)) {
 743                 DBG("Incompatible major versions ([relayd] %u vs [client] %u)",
 744                                 reply.major, be32toh(msg.major));
 745                 ret = -1;
 746                 goto end;
 747         }
 748
 749         conn->major = reply.major;
 750         /* We adapt to the lowest compatible version */
 751         if (reply.minor <= be32toh(msg.minor)) {
 752                 conn->minor = reply.minor;
 753         } else {
 754                 conn->minor = be32toh(msg.minor);
 755         }
 756
 757         if (be32toh(msg.type) == LTTNG_VIEWER_CLIENT_COMMAND) {
 758                 conn->type = RELAY_VIEWER_COMMAND;
 759         } else if (be32toh(msg.type) == LTTNG_VIEWER_CLIENT_NOTIFICATION) {
 760                 conn->type = RELAY_VIEWER_NOTIFICATION;
 761         } else {
 762                 ERR("Unknown connection type : %u", be32toh(msg.type));
 763                 ret = -1;
 764                 goto end;
 765         }
 766
 767         reply.major = htobe32(reply.major);
 768         reply.minor = htobe32(reply.minor);
 769         if (conn->type == RELAY_VIEWER_COMMAND) {
 770                 /*
 771                  * Increment outside of htobe64 macro, because the argument can
 772                  * be used more than once within the macro, and thus the
 773                  * operation may be undefined.
 774                  */
 775                 pthread_mutex_lock(&last_relay_viewer_session_id_lock);
 776                 last_relay_viewer_session_id++;
 777                 pthread_mutex_unlock(&last_relay_viewer_session_id_lock);
 778                 reply.viewer_session_id = htobe64(last_relay_viewer_session_id);
 779         }
 780
 781         health_code_update();
 782
 783         ret = send_response(conn->sock, &reply, sizeof(reply));
 784         if (ret < 0) {
 785                 goto end;
 786         }
 787
 788         health_code_update();
 789
 790         DBG("Version check done using protocol %u.%u", conn->major, conn->minor);
 791         ret = 0;
 792
 793 end:
 794         return ret;
 795 }
 796
 797 /*
 798  * Send the viewer the list of current sessions.
 799  * We need to create a copy of the hash table content because otherwise
 800  * we cannot assume the number of entries stays the same between getting
 801  * the number of HT elements and iteration over the HT.
 802  *
 803  * Return 0 on success or else a negative value.
 804  */
 805 static
 806 int viewer_list_sessions(struct relay_connection *conn)
 807 {
 808         int ret = 0;
 809         struct lttng_viewer_list_sessions session_list;
 810         struct lttng_ht_iter iter;
 811         struct relay_session *session;
 812         struct lttng_viewer_session *send_session_buf = NULL;
 813         uint32_t buf_count = SESSION_BUF_DEFAULT_COUNT;
 814         uint32_t count = 0;
 815
 816         DBG("List sessions received");
 817
 818         send_session_buf = zmalloc(SESSION_BUF_DEFAULT_COUNT * sizeof(*send_session_buf));
 819         if (!send_session_buf) {
 820                 return -1;
 821         }
 822
 823         rcu_read_lock();
 824         cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, session,
 825                         session_n.node) {
 826                 struct lttng_viewer_session *send_session;
 827
 828                 health_code_update();
 829
 830                 if (count >= buf_count) {
 831                         struct lttng_viewer_session *newbuf;
 832                         uint32_t new_buf_count = buf_count << 1;
 833
 834                         newbuf = realloc(send_session_buf,
 835                                 new_buf_count * sizeof(*send_session_buf));
 836                         if (!newbuf) {
 837                                 ret = -1;
 838                                 break;
 839                         }
 840                         send_session_buf = newbuf;
 841                         buf_count = new_buf_count;
 842                 }
 843                 send_session = &send_session_buf[count];
 844                 if (lttng_strncpy(send_session->session_name,
 845                                 session->session_name,
 846                                 sizeof(send_session->session_name))) {
 847                         ret = -1;
 848                         break;
 849                 }
 850                 if (lttng_strncpy(send_session->hostname, session->hostname,
 851                                 sizeof(send_session->hostname))) {
 852                         ret = -1;
 853                         break;
 854                 }
 855                 send_session->id = htobe64(session->id);
 856                 send_session->live_timer = htobe32(session->live_timer);
 857                 if (session->viewer_attached) {
 858                         send_session->clients = htobe32(1);
 859                 } else {
 860                         send_session->clients = htobe32(0);
 861                 }
 862                 send_session->streams = htobe32(session->stream_count);
 863                 count++;
 864         }
 865         rcu_read_unlock();
 866         if (ret < 0) {
 867                 goto end_free;
 868         }
 869
 870         session_list.sessions_count = htobe32(count);
 871
 872         health_code_update();
 873
 874         ret = send_response(conn->sock, &session_list, sizeof(session_list));
 875         if (ret < 0) {
 876                 goto end_free;
 877         }
 878
 879         health_code_update();
 880
 881         ret = send_response(conn->sock, send_session_buf,
 882                         count * sizeof(*send_session_buf));
 883         if (ret < 0) {
 884                 goto end_free;
 885         }
 886         health_code_update();
 887
 888         ret = 0;
 889 end_free:
 890         free(send_session_buf);
 891         return ret;
 892 }
 893
 894 /*
 895  * Send the viewer the list of current streams.
 896  */
 897 static
 898 int viewer_get_new_streams(struct relay_connection *conn)
 899 {
 900         int ret, send_streams = 0;
 901         uint32_t nb_created = 0, nb_unsent = 0, nb_streams = 0, nb_total = 0;
 902         struct lttng_viewer_new_streams_request request;
 903         struct lttng_viewer_new_streams_response response;
 904         struct relay_session *session;
 905         uint64_t session_id;
 906         bool closed = false;
 907
 908         assert(conn);
 909
 910         DBG("Get new streams received");
 911
 912         health_code_update();
 913
 914         /* Receive the request from the connected client. */
 915         ret = recv_request(conn->sock, &request, sizeof(request));
 916         if (ret < 0) {
 917                 goto error;
 918         }
 919         session_id = be64toh(request.session_id);
 920
 921         health_code_update();
 922
 923         memset(&response, 0, sizeof(response));
 924
 925         session = session_get_by_id(session_id);
 926         if (!session) {
 927                 DBG("Relay session %" PRIu64 " not found", session_id);
 928                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR);
 929                 goto send_reply;
 930         }
 931
 932         if (!viewer_session_is_attached(conn->viewer_session, session)) {
 933                 send_streams = 0;
 934                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR);
 935                 goto send_reply;
 936         }
 937
 938         send_streams = 1;
 939         response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_OK);
 940
 941         ret = make_viewer_streams(session, LTTNG_VIEWER_SEEK_LAST, &nb_total, &nb_unsent,
 942                         &nb_created, &closed);
 943         if (ret < 0) {
 944                 goto end_put_session;
 945         }
 946         /* Only send back the newly created streams with the unsent ones. */
 947         nb_streams = nb_created + nb_unsent;
 948         response.streams_count = htobe32(nb_streams);
 949
 950         /*
 951          * If the session is closed, HUP when there are no more streams
 952          * with data.
 953          */
 954         if (closed && nb_total == 0) {
 955                 send_streams = 0;
 956                 response.streams_count = 0;
 957                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_HUP);
 958                 goto send_reply;
 959         }
 960
 961 send_reply:
 962         health_code_update();
 963         ret = send_response(conn->sock, &response, sizeof(response));
 964         if (ret < 0) {
 965                 goto end_put_session;
 966         }
 967         health_code_update();
 968
 969         /*
 970          * Unknown or empty session, just return gracefully, the viewer
 971          * knows what is happening.
 972          */
 973         if (!send_streams || !nb_streams) {
 974                 ret = 0;
 975                 goto end_put_session;
 976         }
 977
 978         /*
 979          * Send stream and *DON'T* ignore the sent flag so every viewer
 980          * streams that were not sent from that point will be sent to
 981          * the viewer.
 982          */
 983         ret = send_viewer_streams(conn->sock, session, 0);
 984         if (ret < 0) {
 985                 goto end_put_session;
 986         }
 987
 988 end_put_session:
 989         if (session) {
 990                 session_put(session);
 991         }
 992 error:
 993         return ret;
 994 }
 995
 996 /*
 997  * Send the viewer the list of current sessions.
 998  */
 999 static
1000 int viewer_attach_session(struct relay_connection *conn)
1001 {
1002         int send_streams = 0;
1003         ssize_t ret;
1004         uint32_t nb_streams = 0;
1005         enum lttng_viewer_seek seek_type;
1006         struct lttng_viewer_attach_session_request request;
1007         struct lttng_viewer_attach_session_response response;
1008         struct relay_session *session = NULL;
1009         bool closed = false;
1010
1011         assert(conn);
1012
1013         health_code_update();
1014
1015         /* Receive the request from the connected client. */
1016         ret = recv_request(conn->sock, &request, sizeof(request));
1017         if (ret < 0) {
1018                 goto error;
1019         }
1020
1021         health_code_update();
1022
1023         memset(&response, 0, sizeof(response));
1024
1025         if (!conn->viewer_session) {
1026                 DBG("Client trying to attach before creating a live viewer session");
1027                 response.status = htobe32(LTTNG_VIEWER_ATTACH_NO_SESSION);
1028                 goto send_reply;
1029         }
1030
1031         session = session_get_by_id(be64toh(request.session_id));
1032         if (!session) {
1033                 DBG("Relay session %" PRIu64 " not found",
1034                                 be64toh(request.session_id));
1035                 response.status = htobe32(LTTNG_VIEWER_ATTACH_UNK);
1036                 goto send_reply;
1037         }
1038         DBG("Attach session ID %" PRIu64 " received",
1039                 be64toh(request.session_id));
1040
1041         if (session->live_timer == 0) {
1042                 DBG("Not live session");
1043                 response.status = htobe32(LTTNG_VIEWER_ATTACH_NOT_LIVE);
1044                 goto send_reply;
1045         }
1046
1047         send_streams = 1;
1048         ret = viewer_session_attach(conn->viewer_session, session);
1049         if (ret) {
1050                 DBG("Already a viewer attached");
1051                 response.status = htobe32(LTTNG_VIEWER_ATTACH_ALREADY);
1052                 goto send_reply;
1053         }
1054
1055         switch (be32toh(request.seek)) {
1056         case LTTNG_VIEWER_SEEK_BEGINNING:
1057         case LTTNG_VIEWER_SEEK_LAST:
1058                 response.status = htobe32(LTTNG_VIEWER_ATTACH_OK);
1059                 seek_type = be32toh(request.seek);
1060                 break;
1061         default:
1062                 ERR("Wrong seek parameter");
1063                 response.status = htobe32(LTTNG_VIEWER_ATTACH_SEEK_ERR);
1064                 send_streams = 0;
1065                 goto send_reply;
1066         }
1067
1068         ret = make_viewer_streams(session, seek_type, &nb_streams, NULL,
1069                         NULL, &closed);
1070         if (ret < 0) {
1071                 goto end_put_session;
1072         }
1073         response.streams_count = htobe32(nb_streams);
1074
1075         /*
1076          * If the session is closed when the viewer is attaching, it
1077          * means some of the streams may have been concurrently removed,
1078          * so we don't allow the viewer to attach, even if there are
1079          * streams available.
1080          */
1081         if (closed) {
1082                 send_streams = 0;
1083                 response.streams_count = 0;
1084                 response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_HUP);
1085                 goto send_reply;
1086         }
1087
1088 send_reply:
1089         health_code_update();
1090         ret = send_response(conn->sock, &response, sizeof(response));
1091         if (ret < 0) {
1092                 goto end_put_session;
1093         }
1094         health_code_update();
1095
1096         /*
1097          * Unknown or empty session, just return gracefully, the viewer
1098          * knows what is happening.
1099          */
1100         if (!send_streams || !nb_streams) {
1101                 ret = 0;
1102                 goto end_put_session;
1103         }
1104
1105         /* Send stream and ignore the sent flag. */
1106         ret = send_viewer_streams(conn->sock, session, 1);
1107         if (ret < 0) {
1108                 goto end_put_session;
1109         }
1110
1111 end_put_session:
1112         if (session) {
1113                 session_put(session);
1114         }
1115 error:
1116         return ret;
1117 }
1118
1119 /*
1120  * Open the index file if needed for the given vstream.
1121  *
1122  * If an index file is successfully opened, the vstream index_fd set with
1123  * it.
1124  *
1125  * Return 0 on success, a negative value on error (-ENOENT if not ready yet).
1126  *
1127  * Called with rstream lock held.
1128  */
1129 static int try_open_index(struct relay_viewer_stream *vstream,
1130                 struct relay_stream *rstream)
1131 {
1132         int ret = 0;
1133
1134         if (vstream->index_fd) {
1135                 goto end;
1136         }
1137
1138         /*
1139          * First time, we open the index file and at least one index is ready.
1140          */
1141         if (rstream->index_received_seqcount == 0) {
1142                 ret = -ENOENT;
1143                 goto end;
1144         }
1145         ret = index_open(vstream->path_name, vstream->channel_name,
1146                         vstream->stream->tracefile_count,
1147                         vstream->current_tracefile_id);
1148         if (ret >= 0) {
1149                 vstream->index_fd = stream_fd_create(ret);
1150                 if (!vstream->index_fd) {
1151                         if (close(ret)) {
1152                                 PERROR("close");
1153                         }
1154                         ret = -1;
1155                 } else {
1156                         ret = 0;
1157                 }
1158                 goto end;
1159         }
1160
1161 end:
1162         return ret;
1163 }
1164
1165 /*
1166  * Check the status of the index for the given stream. This function
1167  * updates the index structure if needed and can put (close) the vstream
1168  * in the HUP situation.
1169  *
1170  * Return 0 means that we can proceed with the index. A value of 1 means
1171  * that the index has been updated and is ready to be sent to the
1172  * client. A negative value indicates an error that can't be handled.
1173  *
1174  * Called with rstream lock held.
1175  */
1176 static int check_index_status(struct relay_viewer_stream *vstream,
1177                 struct relay_stream *rstream, struct ctf_trace *trace,
1178                 struct lttng_viewer_index *index)
1179 {
1180         int ret;
1181
1182         if (trace->session->connection_closed
1183                         && rstream->index_received_seqcount
1184                                 == vstream->index_sent_seqcount) {
1185                 /* Last index sent and session connection is closed. */
1186                 index->status = htobe32(LTTNG_VIEWER_INDEX_HUP);
1187                 goto hup;
1188         } else if (rstream->beacon_ts_end != -1ULL &&
1189                         rstream->index_received_seqcount
1190                                 == vstream->index_sent_seqcount) {
1191                 /*
1192                  * We've received a synchronization beacon and the last index
1193                  * available has been sent, the index for now is inactive.
1194                  *
1195                  * In this case, we have received a beacon which allows us to
1196                  * inform the client of a time interval during which we can
1197                  * guarantee that there are no events to read (and never will
1198                  * be).
1199                  */
1200                 index->status = htobe32(LTTNG_VIEWER_INDEX_INACTIVE);
1201                 index->timestamp_end = htobe64(rstream->beacon_ts_end);
1202                 index->stream_id = htobe64(rstream->ctf_stream_id);
1203                 goto index_ready;
1204         } else if (rstream->index_received_seqcount
1205                         == vstream->index_sent_seqcount) {
1206                 /*
1207                  * This checks whether received == sent seqcount. In
1208                  * this case, we have not received a beacon. Therefore,
1209                  * we can only ask the client to retry later.
1210                  */
1211                 index->status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
1212                 goto index_ready;
1213         } else if (!tracefile_array_seq_in_file(rstream->tfa,
1214                         vstream->current_tracefile_id,
1215                         vstream->index_sent_seqcount)) {
1216                 /*
1217                  * The next index we want to send cannot be read either
1218                  * because we need to perform a rotation, or due to
1219                  * the producer having overwritten its trace file.
1220                  */
1221                 DBG("Viewer stream %" PRIu64 " rotation",
1222                                 vstream->stream->stream_handle);
1223                 ret = viewer_stream_rotate(vstream);
1224                 if (ret < 0) {
1225                         goto end;
1226                 } else if (ret == 1) {
1227                         /* EOF across entire stream. */
1228                         index->status = htobe32(LTTNG_VIEWER_INDEX_HUP);
1229                         goto hup;
1230                 }
1231                 /*
1232                  * If we have been pushed due to overwrite, it
1233                  * necessarily means there is data that can be read in
1234                  * the stream. If we rotated because we reached the end
1235                  * of a tracefile, it means the following tracefile
1236                  * needs to contain at least one index, else we would
1237                  * have already returned LTTNG_VIEWER_INDEX_RETRY to the
1238                  * viewer. The updated index_sent_seqcount needs to
1239                  * point to a readable index entry now.
1240                  *
1241                  * In the case where we "rotate" on a single file, we
1242                  * can end up in a case where the requested index is
1243                  * still unavailable.
1244                  */
1245                 if (rstream->tracefile_count == 1 &&
1246                                 !tracefile_array_seq_in_file(
1247                                         rstream->tfa,
1248                                         vstream->current_tracefile_id,
1249                                         vstream->index_sent_seqcount)) {
1250                         index->status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
1251                         goto index_ready;
1252                 }
1253                 assert(tracefile_array_seq_in_file(rstream->tfa,
1254                                 vstream->current_tracefile_id,
1255                                 vstream->index_sent_seqcount));
1256         }
1257         /* ret == 0 means successful so we continue. */
1258         ret = 0;
1259 end:
1260         return ret;
1261
1262 hup:
1263         viewer_stream_put(vstream);
1264 index_ready:
1265         return 1;
1266 }
1267
1268 /*
1269  * Send the next index for a stream.
1270  *
1271  * Return 0 on success or else a negative value.
1272  */
1273 static
1274 int viewer_get_next_index(struct relay_connection *conn)
1275 {
1276         int ret;
1277         ssize_t read_ret;
1278         struct lttng_viewer_get_next_index request_index;
1279         struct lttng_viewer_index viewer_index;
1280         struct ctf_packet_index packet_index;
1281         struct relay_viewer_stream *vstream = NULL;
1282         struct relay_stream *rstream = NULL;
1283         struct ctf_trace *ctf_trace = NULL;
1284         struct relay_viewer_stream *metadata_viewer_stream = NULL;
1285
1286         assert(conn);
1287
1288         DBG("Viewer get next index");
1289
1290         memset(&viewer_index, 0, sizeof(viewer_index));
1291         health_code_update();
1292
1293         ret = recv_request(conn->sock, &request_index, sizeof(request_index));
1294         if (ret < 0) {
1295                 goto end;
1296         }
1297         health_code_update();
1298
1299         vstream = viewer_stream_get_by_id(be64toh(request_index.stream_id));
1300         if (!vstream) {
1301                 DBG("Client requested index of unknown stream id %" PRIu64,
1302                                 be64toh(request_index.stream_id));
1303                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1304                 goto send_reply;
1305         }
1306
1307         /* Use back. ref. Protected by refcounts. */
1308         rstream = vstream->stream;
1309         ctf_trace = rstream->trace;
1310
1311         /* metadata_viewer_stream may be NULL. */
1312         metadata_viewer_stream =
1313                         ctf_trace_get_viewer_metadata_stream(ctf_trace);
1314
1315         pthread_mutex_lock(&rstream->lock);
1316
1317         /*
1318          * The viewer should not ask for index on metadata stream.
1319          */
1320         if (rstream->is_metadata) {
1321                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_HUP);
1322                 goto send_reply;
1323         }
1324
1325         /* Try to open an index if one is needed for that stream. */
1326         ret = try_open_index(vstream, rstream);
1327         if (ret < 0) {
1328                 if (ret == -ENOENT) {
1329                         /*
1330                          * The index is created only when the first data
1331                          * packet arrives, it might not be ready at the
1332                          * beginning of the session
1333                          */
1334                         viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_RETRY);
1335                 } else {
1336                         /* Unhandled error. */
1337                         viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1338                 }
1339                 goto send_reply;
1340         }
1341
1342         ret = check_index_status(vstream, rstream, ctf_trace, &viewer_index);
1343         if (ret < 0) {
1344                 goto error_put;
1345         } else if (ret == 1) {
1346                 /*
1347                  * We have no index to send and check_index_status has populated
1348                  * viewer_index's status.
1349                  */
1350                 goto send_reply;
1351         }
1352         /* At this point, ret is 0 thus we will be able to read the index. */
1353         assert(!ret);
1354
1355         /*
1356          * vstream->stream_fd may be NULL if it has been closed by
1357          * tracefile rotation, or if we are at the beginning of the
1358          * stream. We open the data stream file here to protect against
1359          * overwrite caused by tracefile rotation (in association with
1360          * unlink performed before overwrite).
1361          */
1362         if (!vstream->stream_fd) {
1363                 char fullpath[PATH_MAX];
1364
1365                 if (vstream->stream->tracefile_count > 0) {
1366                         ret = snprintf(fullpath, PATH_MAX, "%s/%s_%" PRIu64,
1367                                         vstream->path_name,
1368                                         vstream->channel_name,
1369                                         vstream->current_tracefile_id);
1370                 } else {
1371                         ret = snprintf(fullpath, PATH_MAX, "%s/%s",
1372                                         vstream->path_name,
1373                                         vstream->channel_name);
1374                 }
1375                 if (ret < 0) {
1376                         goto error_put;
1377                 }
1378                 ret = open(fullpath, O_RDONLY);
1379                 if (ret < 0) {
1380                         PERROR("Relay opening trace file");
1381                         goto error_put;
1382                 }
1383                 vstream->stream_fd = stream_fd_create(ret);
1384                 if (!vstream->stream_fd) {
1385                         if (close(ret)) {
1386                                 PERROR("close");
1387                         }
1388                         goto error_put;
1389                 }
1390         }
1391
1392         ret = check_new_streams(conn);
1393         if (ret < 0) {
1394                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1395                 goto send_reply;
1396         } else if (ret == 1) {
1397                 viewer_index.flags |= LTTNG_VIEWER_FLAG_NEW_STREAM;
1398         }
1399
1400         read_ret = lttng_read(vstream->index_fd->fd, &packet_index,
1401                         sizeof(packet_index));
1402         if (read_ret < sizeof(packet_index)) {
1403                 ERR("Relay reading index file %d returned %zd",
1404                         vstream->index_fd->fd, read_ret);
1405                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_ERR);
1406                 goto send_reply;
1407         } else {
1408                 viewer_index.status = htobe32(LTTNG_VIEWER_INDEX_OK);
1409                 vstream->index_sent_seqcount++;
1410         }
1411
1412         /*
1413          * Indexes are stored in big endian, no need to switch before sending.
1414          */
1415         DBG("Sending viewer index for stream %" PRIu64 " offset %" PRIu64,
1416                 rstream->stream_handle,
1417                 be64toh(packet_index.offset));
1418         viewer_index.offset = packet_index.offset;
1419         viewer_index.packet_size = packet_index.packet_size;
1420         viewer_index.content_size = packet_index.content_size;
1421         viewer_index.timestamp_begin = packet_index.timestamp_begin;
1422         viewer_index.timestamp_end = packet_index.timestamp_end;
1423         viewer_index.events_discarded = packet_index.events_discarded;
1424         viewer_index.stream_id = packet_index.stream_id;
1425
1426 send_reply:
1427         if (rstream) {
1428                 pthread_mutex_unlock(&rstream->lock);
1429         }
1430
1431         if (metadata_viewer_stream) {
1432                 pthread_mutex_lock(&metadata_viewer_stream->stream->lock);
1433                 DBG("get next index metadata check: recv %" PRIu64
1434                                 " sent %" PRIu64,
1435                         metadata_viewer_stream->stream->metadata_received,
1436                         metadata_viewer_stream->metadata_sent);
1437                 if (!metadata_viewer_stream->stream->metadata_received ||
1438                                 metadata_viewer_stream->stream->metadata_received >
1439                                         metadata_viewer_stream->metadata_sent) {
1440                         viewer_index.flags |= LTTNG_VIEWER_FLAG_NEW_METADATA;
1441                 }
1442                 pthread_mutex_unlock(&metadata_viewer_stream->stream->lock);
1443         }
1444
1445         viewer_index.flags = htobe32(viewer_index.flags);
1446         health_code_update();
1447
1448         ret = send_response(conn->sock, &viewer_index, sizeof(viewer_index));
1449         if (ret < 0) {
1450                 goto end;
1451         }
1452         health_code_update();
1453
1454         if (vstream) {
1455                 DBG("Index %" PRIu64 " for stream %" PRIu64 " sent",
1456                                 vstream->index_sent_seqcount,
1457                                 vstream->stream->stream_handle);
1458         }
1459 end:
1460         if (metadata_viewer_stream) {
1461                 viewer_stream_put(metadata_viewer_stream);
1462         }
1463         if (vstream) {
1464                 viewer_stream_put(vstream);
1465         }
1466         return ret;
1467
1468 error_put:
1469         pthread_mutex_unlock(&rstream->lock);
1470         if (metadata_viewer_stream) {
1471                 viewer_stream_put(metadata_viewer_stream);
1472         }
1473         viewer_stream_put(vstream);
1474         return ret;
1475 }
1476
1477 /*
1478  * Send the next index for a stream
1479  *
1480  * Return 0 on success or else a negative value.
1481  */
1482 static
1483 int viewer_get_packet(struct relay_connection *conn)
1484 {
1485         int ret, send_data = 0;
1486         char *data = NULL;
1487         uint32_t len = 0;
1488         ssize_t read_len;
1489         struct lttng_viewer_get_packet get_packet_info;
1490         struct lttng_viewer_trace_packet reply;
1491         struct relay_viewer_stream *vstream = NULL;
1492
1493         DBG2("Relay get data packet");
1494
1495         health_code_update();
1496
1497         ret = recv_request(conn->sock, &get_packet_info,
1498                         sizeof(get_packet_info));
1499         if (ret < 0) {
1500                 goto end;
1501         }
1502         health_code_update();
1503
1504         /* From this point on, the error label can be reached. */
1505         memset(&reply, 0, sizeof(reply));
1506
1507         vstream = viewer_stream_get_by_id(be64toh(get_packet_info.stream_id));
1508         if (!vstream) {
1509                 DBG("Client requested packet of unknown stream id %" PRIu64,
1510                                 be64toh(get_packet_info.stream_id));
1511                 reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_ERR);
1512                 goto send_reply_nolock;
1513         }
1514
1515         pthread_mutex_lock(&vstream->stream->lock);
1516
1517         len = be32toh(get_packet_info.len);
1518         data = zmalloc(len);
1519         if (!data) {
1520                 PERROR("relay data zmalloc");
1521                 goto error;
1522         }
1523
1524         ret = lseek(vstream->stream_fd->fd, be64toh(get_packet_info.offset),
1525                         SEEK_SET);
1526         if (ret < 0) {
1527                 PERROR("lseek fd %d to offset %" PRIu64, vstream->stream_fd->fd,
1528                         be64toh(get_packet_info.offset));
1529                 goto error;
1530         }
1531         read_len = lttng_read(vstream->stream_fd->fd, data, len);
1532         if (read_len < len) {
1533                 PERROR("Relay reading trace file, fd: %d, offset: %" PRIu64,
1534                                 vstream->stream_fd->fd,
1535                                 be64toh(get_packet_info.offset));
1536                 goto error;
1537         }
1538         reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_OK);
1539         reply.len = htobe32(len);
1540         send_data = 1;
1541         goto send_reply;
1542
1543 error:
1544         reply.status = htobe32(LTTNG_VIEWER_GET_PACKET_ERR);
1545
1546 send_reply:
1547         if (vstream) {
1548                 pthread_mutex_unlock(&vstream->stream->lock);
1549         }
1550 send_reply_nolock:
1551         reply.flags = htobe32(reply.flags);
1552
1553         health_code_update();
1554
1555         ret = send_response(conn->sock, &reply, sizeof(reply));
1556         if (ret < 0) {
1557                 goto end_free;
1558         }
1559         health_code_update();
1560
1561         if (send_data) {
1562                 health_code_update();
1563                 ret = send_response(conn->sock, data, len);
1564                 if (ret < 0) {
1565                         goto end_free;
1566                 }
1567                 health_code_update();
1568         }
1569
1570         DBG("Sent %u bytes for stream %" PRIu64, len,
1571                         be64toh(get_packet_info.stream_id));
1572
1573 end_free:
1574         free(data);
1575 end:
1576         if (vstream) {
1577                 viewer_stream_put(vstream);
1578         }
1579         return ret;
1580 }
1581
1582 /*
1583  * Send the session's metadata
1584  *
1585  * Return 0 on success else a negative value.
1586  */
1587 static
1588 int viewer_get_metadata(struct relay_connection *conn)
1589 {
1590         int ret = 0;
1591         ssize_t read_len;
1592         uint64_t len = 0;
1593         char *data = NULL;
1594         struct lttng_viewer_get_metadata request;
1595         struct lttng_viewer_metadata_packet reply;
1596         struct relay_viewer_stream *vstream = NULL;
1597
1598         assert(conn);
1599
1600         DBG("Relay get metadata");
1601
1602         health_code_update();
1603
1604         ret = recv_request(conn->sock, &request, sizeof(request));
1605         if (ret < 0) {
1606                 goto end;
1607         }
1608         health_code_update();
1609
1610         memset(&reply, 0, sizeof(reply));
1611
1612         vstream = viewer_stream_get_by_id(be64toh(request.stream_id));
1613         if (!vstream) {
1614                 /*
1615                  * The metadata stream can be closed by a CLOSE command
1616                  * just before we attach. It can also be closed by
1617                  * per-pid tracing during tracing. Therefore, it is
1618                  * possible that we cannot find this viewer stream.
1619                  * Reply back to the client with an error if we cannot
1620                  * find it.
1621                  */
1622                 DBG("Client requested metadata of unknown stream id %" PRIu64,
1623                                 be64toh(request.stream_id));
1624                 reply.status = htobe32(LTTNG_VIEWER_METADATA_ERR);
1625                 goto send_reply;
1626         }
1627         pthread_mutex_lock(&vstream->stream->lock);
1628         if (!vstream->stream->is_metadata) {
1629                 ERR("Invalid metadata stream");
1630                 goto error;
1631         }
1632
1633         assert(vstream->metadata_sent <= vstream->stream->metadata_received);
1634
1635         len = vstream->stream->metadata_received - vstream->metadata_sent;
1636         if (len == 0) {
1637                 reply.status = htobe32(LTTNG_VIEWER_NO_NEW_METADATA);
1638                 goto send_reply;
1639         }
1640
1641         /* first time, we open the metadata file */
1642         if (!vstream->stream_fd) {
1643                 char fullpath[PATH_MAX];
1644
1645                 ret = snprintf(fullpath, PATH_MAX, "%s/%s", vstream->path_name,
1646                                 vstream->channel_name);
1647                 if (ret < 0) {
1648                         goto error;
1649                 }
1650                 ret = open(fullpath, O_RDONLY);
1651                 if (ret < 0) {
1652                         PERROR("Relay opening metadata file");
1653                         goto error;
1654                 }
1655                 vstream->stream_fd = stream_fd_create(ret);
1656                 if (!vstream->stream_fd) {
1657                         if (close(ret)) {
1658                                 PERROR("close");
1659                         }
1660                         goto error;
1661                 }
1662         }
1663
1664         reply.len = htobe64(len);
1665         data = zmalloc(len);
1666         if (!data) {
1667                 PERROR("viewer metadata zmalloc");
1668                 goto error;
1669         }
1670
1671         read_len = lttng_read(vstream->stream_fd->fd, data, len);
1672         if (read_len < len) {
1673                 PERROR("Relay reading metadata file");
1674                 goto error;
1675         }
1676         vstream->metadata_sent += read_len;
1677         if (vstream->metadata_sent == vstream->stream->metadata_received
1678                         && vstream->stream->closed) {
1679                 /* Release ownership for the viewer metadata stream. */
1680                 viewer_stream_put(vstream);
1681         }
1682
1683         reply.status = htobe32(LTTNG_VIEWER_METADATA_OK);
1684
1685         goto send_reply;
1686
1687 error:
1688         reply.status = htobe32(LTTNG_VIEWER_METADATA_ERR);
1689
1690 send_reply:
1691         health_code_update();
1692         if (vstream) {
1693                 pthread_mutex_unlock(&vstream->stream->lock);
1694         }
1695         ret = send_response(conn->sock, &reply, sizeof(reply));
1696         if (ret < 0) {
1697                 goto end_free;
1698         }
1699         health_code_update();
1700
1701         if (len > 0) {
1702                 ret = send_response(conn->sock, data, len);
1703                 if (ret < 0) {
1704                         goto end_free;
1705                 }
1706         }
1707
1708         DBG("Sent %" PRIu64 " bytes of metadata for stream %" PRIu64, len,
1709                         be64toh(request.stream_id));
1710
1711         DBG("Metadata sent");
1712
1713 end_free:
1714         free(data);
1715 end:
1716         if (vstream) {
1717                 viewer_stream_put(vstream);
1718         }
1719         return ret;
1720 }
1721
1722 /*
1723  * Create a viewer session.
1724  *
1725  * Return 0 on success or else a negative value.
1726  */
1727 static
1728 int viewer_create_session(struct relay_connection *conn)
1729 {
1730         int ret;
1731         struct lttng_viewer_create_session_response resp;
1732
1733         DBG("Viewer create session received");
1734
1735         memset(&resp, 0, sizeof(resp));
1736         resp.status = htobe32(LTTNG_VIEWER_CREATE_SESSION_OK);
1737         conn->viewer_session = viewer_session_create();
1738         if (!conn->viewer_session) {
1739                 ERR("Allocation viewer session");
1740                 resp.status = htobe32(LTTNG_VIEWER_CREATE_SESSION_ERR);
1741                 goto send_reply;
1742         }
1743
1744 send_reply:
1745         health_code_update();
1746         ret = send_response(conn->sock, &resp, sizeof(resp));
1747         if (ret < 0) {
1748                 goto end;
1749         }
1750         health_code_update();
1751         ret = 0;
1752
1753 end:
1754         return ret;
1755 }
1756
1757 /*
1758  * Detach a viewer session.
1759  *
1760  * Return 0 on success or else a negative value.
1761  */
1762 static
1763 int viewer_detach_session(struct relay_connection *conn)
1764 {
1765         int ret;
1766         struct lttng_viewer_detach_session_response response;
1767         struct lttng_viewer_detach_session_request request;
1768         struct relay_session *session = NULL;
1769         uint64_t viewer_session_to_close;
1770
1771         DBG("Viewer detach session received");
1772
1773         assert(conn);
1774
1775         health_code_update();
1776
1777         /* Receive the request from the connected client. */
1778         ret = recv_request(conn->sock, &request, sizeof(request));
1779         if (ret < 0) {
1780                 goto end;
1781         }
1782         viewer_session_to_close = be64toh(request.session_id);
1783
1784         if (!conn->viewer_session) {
1785                 DBG("Client trying to detach before creating a live viewer session");
1786                 response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR);
1787                 goto send_reply;
1788         }
1789
1790         health_code_update();
1791
1792         memset(&response, 0, sizeof(response));
1793         DBG("Detaching from session ID %" PRIu64, viewer_session_to_close);
1794
1795         session = session_get_by_id(be64toh(request.session_id));
1796         if (!session) {
1797                 DBG("Relay session %" PRIu64 " not found",
1798                                 be64toh(request.session_id));
1799                 response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_UNK);
1800                 goto send_reply;
1801         }
1802
1803         ret = viewer_session_is_attached(conn->viewer_session, session);
1804         if (ret != 1) {
1805                 DBG("Not attached to this session");
1806                 response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR);
1807                 goto send_reply_put;
1808         }
1809
1810         viewer_session_close_one_session(conn->viewer_session, session);
1811         response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_OK);
1812         DBG("Session %" PRIu64 " detached.", viewer_session_to_close);
1813
1814 send_reply_put:
1815         session_put(session);
1816
1817 send_reply:
1818         health_code_update();
1819         ret = send_response(conn->sock, &response, sizeof(response));
1820         if (ret < 0) {
1821                 goto end;
1822         }
1823         health_code_update();
1824         ret = 0;
1825
1826 end:
1827         return ret;
1828 }
1829
1830 /*
1831  * live_relay_unknown_command: send -1 if received unknown command
1832  */
1833 static
1834 void live_relay_unknown_command(struct relay_connection *conn)
1835 {
1836         struct lttcomm_relayd_generic_reply reply;
1837
1838         memset(&reply, 0, sizeof(reply));
1839         reply.ret_code = htobe32(LTTNG_ERR_UNK);
1840         (void) send_response(conn->sock, &reply, sizeof(reply));
1841 }
1842
1843 /*
1844  * Process the commands received on the control socket
1845  */
1846 static
1847 int process_control(struct lttng_viewer_cmd *recv_hdr,
1848                 struct relay_connection *conn)
1849 {
1850         int ret = 0;
1851         uint32_t msg_value;
1852
1853         msg_value = be32toh(recv_hdr->cmd);
1854
1855         /*
1856          * Make sure we've done the version check before any command other then a
1857          * new client connection.
1858          */
1859         if (msg_value != LTTNG_VIEWER_CONNECT && !conn->version_check_done) {
1860                 ERR("Viewer conn value %" PRIu32 " before version check", msg_value);
1861                 ret = -1;
1862                 goto end;
1863         }
1864
1865         switch (msg_value) {
1866         case LTTNG_VIEWER_CONNECT:
1867                 ret = viewer_connect(conn);
1868                 break;
1869         case LTTNG_VIEWER_LIST_SESSIONS:
1870                 ret = viewer_list_sessions(conn);
1871                 break;
1872         case LTTNG_VIEWER_ATTACH_SESSION:
1873                 ret = viewer_attach_session(conn);
1874                 break;
1875         case LTTNG_VIEWER_GET_NEXT_INDEX:
1876                 ret = viewer_get_next_index(conn);
1877                 break;
1878         case LTTNG_VIEWER_GET_PACKET:
1879                 ret = viewer_get_packet(conn);
1880                 break;
1881         case LTTNG_VIEWER_GET_METADATA:
1882                 ret = viewer_get_metadata(conn);
1883                 break;
1884         case LTTNG_VIEWER_GET_NEW_STREAMS:
1885                 ret = viewer_get_new_streams(conn);
1886                 break;
1887         case LTTNG_VIEWER_CREATE_SESSION:
1888                 ret = viewer_create_session(conn);
1889                 break;
1890         case LTTNG_VIEWER_DETACH_SESSION:
1891                 ret = viewer_detach_session(conn);
1892                 break;
1893         default:
1894                 ERR("Received unknown viewer command (%u)",
1895                                 be32toh(recv_hdr->cmd));
1896                 live_relay_unknown_command(conn);
1897                 ret = -1;
1898                 goto end;
1899         }
1900
1901 end:
1902         return ret;
1903 }
1904
1905 static
1906 void cleanup_connection_pollfd(struct lttng_poll_event *events, int pollfd)
1907 {
1908         int ret;
1909
1910         (void) lttng_poll_del(events, pollfd);
1911
1912         ret = close(pollfd);
1913         if (ret < 0) {
1914                 ERR("Closing pollfd %d", pollfd);
1915         }
1916 }
1917
1918 /*
1919  * This thread does the actual work
1920  */
1921 static
1922 void *thread_worker(void *data)
1923 {
1924         int ret, err = -1;
1925         uint32_t nb_fd;
1926         struct lttng_poll_event events;
1927         struct lttng_ht *viewer_connections_ht;
1928         struct lttng_ht_iter iter;
1929         struct lttng_viewer_cmd recv_hdr;
1930         struct relay_connection *destroy_conn;
1931
1932         DBG("[thread] Live viewer relay worker started");
1933
1934         rcu_register_thread();
1935
1936         health_register(health_relayd, HEALTH_RELAYD_TYPE_LIVE_WORKER);
1937
1938         if (testpoint(relayd_thread_live_worker)) {
1939                 goto error_testpoint;
1940         }
1941
1942         /* table of connections indexed on socket */
1943         viewer_connections_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1944         if (!viewer_connections_ht) {
1945                 goto viewer_connections_ht_error;
1946         }
1947
1948         ret = create_thread_poll_set(&events, 2);
1949         if (ret < 0) {
1950                 goto error_poll_create;
1951         }
1952
1953         ret = lttng_poll_add(&events, live_conn_pipe[0], LPOLLIN | LPOLLRDHUP);
1954         if (ret < 0) {
1955                 goto error;
1956         }
1957
1958 restart:
1959         while (1) {
1960                 int i;
1961
1962                 health_code_update();
1963
1964                 /* Infinite blocking call, waiting for transmission */
1965                 DBG3("Relayd live viewer worker thread polling...");
1966                 health_poll_entry();
1967                 ret = lttng_poll_wait(&events, -1);
1968                 health_poll_exit();
1969                 if (ret < 0) {
1970                         /*
1971                          * Restart interrupted system call.
1972                          */
1973                         if (errno == EINTR) {
1974                                 goto restart;
1975                         }
1976                         goto error;
1977                 }
1978
1979                 nb_fd = ret;
1980
1981                 /*
1982                  * Process control. The control connection is prioritised so we don't
1983                  * starve it with high throughput tracing data on the data
1984                  * connection.
1985                  */
1986                 for (i = 0; i < nb_fd; i++) {
1987                         /* Fetch once the poll data */
1988                         uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1989                         int pollfd = LTTNG_POLL_GETFD(&events, i);
1990
1991                         health_code_update();
1992
1993                         if (!revents) {
1994                                 /* No activity for this FD (poll implementation). */
1995                                 continue;
1996                         }
1997
1998                         /* Thread quit pipe has been closed. Killing thread. */
1999                         ret = check_thread_quit_pipe(pollfd, revents);
2000                         if (ret) {
2001                                 err = 0;
2002                                 goto exit;
2003                         }
2004
2005                         /* Inspect the relay conn pipe for new connection. */
2006                         if (pollfd == live_conn_pipe[0]) {
2007                                 if (revents & LPOLLIN) {
2008                                         struct relay_connection *conn;
2009
2010                                         ret = lttng_read(live_conn_pipe[0],
2011                                                         &conn, sizeof(conn));
2012                                         if (ret < 0) {
2013                                                 goto error;
2014                                         }
2015                                         lttng_poll_add(&events, conn->sock->fd,
2016                                                         LPOLLIN | LPOLLRDHUP);
2017                                         connection_ht_add(viewer_connections_ht, conn);
2018                                         DBG("Connection socket %d added to poll", conn->sock->fd);
2019                                 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2020                                         ERR("Relay live pipe error");
2021                                         goto error;
2022                                 } else {
2023                                         ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2024                                         goto error;
2025                                 }
2026                         } else {
2027                                 /* Connection activity. */
2028                                 struct relay_connection *conn;
2029
2030                                 conn = connection_get_by_sock(viewer_connections_ht, pollfd);
2031                                 if (!conn) {
2032                                         continue;
2033                                 }
2034
2035                                 if (revents & LPOLLIN) {
2036                                         ret = conn->sock->ops->recvmsg(conn->sock, &recv_hdr,
2037                                                         sizeof(recv_hdr), 0);
2038                                         if (ret <= 0) {
2039                                                 /* Connection closed. */
2040                                                 cleanup_connection_pollfd(&events, pollfd);
2041                                                 /* Put "create" ownership reference. */
2042                                                 connection_put(conn);
2043                                                 DBG("Viewer control conn closed with %d", pollfd);
2044                                         } else {
2045                                                 ret = process_control(&recv_hdr, conn);
2046                                                 if (ret < 0) {
2047                                                         /* Clear the session on error. */
2048                                                         cleanup_connection_pollfd(&events, pollfd);
2049                                                         /* Put "create" ownership reference. */
2050                                                         connection_put(conn);
2051                                                         DBG("Viewer connection closed with %d", pollfd);
2052                                                 }
2053                                         }
2054                                 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2055                                         cleanup_connection_pollfd(&events, pollfd);
2056                                         /* Put "create" ownership reference. */
2057                                         connection_put(conn);
2058                                 } else {
2059                                         ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2060                                         connection_put(conn);
2061                                         goto error;
2062                                 }
2063                                 /* Put local "get_by_sock" reference. */
2064                                 connection_put(conn);
2065                         }
2066                 }
2067         }
2068
2069 exit:
2070 error:
2071         lttng_poll_clean(&events);
2072
2073         /* Cleanup reamaining connection object. */
2074         rcu_read_lock();
2075         cds_lfht_for_each_entry(viewer_connections_ht->ht, &iter.iter,
2076                         destroy_conn,
2077                         sock_n.node) {
2078                 health_code_update();
2079                 connection_put(destroy_conn);
2080         }
2081         rcu_read_unlock();
2082 error_poll_create:
2083         lttng_ht_destroy(viewer_connections_ht);
2084 viewer_connections_ht_error:
2085         /* Close relay conn pipes */
2086         utils_close_pipe(live_conn_pipe);
2087         if (err) {
2088                 DBG("Viewer worker thread exited with error");
2089         }
2090         DBG("Viewer worker thread cleanup complete");
2091 error_testpoint:
2092         if (err) {
2093                 health_error();
2094                 ERR("Health error occurred in %s", __func__);
2095         }
2096         health_unregister(health_relayd);
2097         if (lttng_relay_stop_threads()) {
2098                 ERR("Error stopping threads");
2099         }
2100         rcu_unregister_thread();
2101         return NULL;
2102 }
2103
2104 /*
2105  * Create the relay command pipe to wake thread_manage_apps.
2106  * Closed in cleanup().
2107  */
2108 static int create_conn_pipe(void)
2109 {
2110         return utils_create_pipe_cloexec(live_conn_pipe);
2111 }
2112
2113 int relayd_live_join(void)
2114 {
2115         int ret, retval = 0;
2116         void *status;
2117
2118         ret = pthread_join(live_listener_thread, &status);
2119         if (ret) {
2120                 errno = ret;
2121                 PERROR("pthread_join live listener");
2122                 retval = -1;
2123         }
2124
2125         ret = pthread_join(live_worker_thread, &status);
2126         if (ret) {
2127                 errno = ret;
2128                 PERROR("pthread_join live worker");
2129                 retval = -1;
2130         }
2131
2132         ret = pthread_join(live_dispatcher_thread, &status);
2133         if (ret) {
2134                 errno = ret;
2135                 PERROR("pthread_join live dispatcher");
2136                 retval = -1;
2137         }
2138
2139         cleanup_relayd_live();
2140
2141         return retval;
2142 }
2143
2144 /*
2145  * main
2146  */
2147 int relayd_live_create(struct lttng_uri *uri)
2148 {
2149         int ret = 0, retval = 0;
2150         void *status;
2151         int is_root;
2152
2153         if (!uri) {
2154                 retval = -1;
2155                 goto exit_init_data;
2156         }
2157         live_uri = uri;
2158
2159         /* Check if daemon is UID = 0 */
2160         is_root = !getuid();
2161
2162         if (!is_root) {
2163                 if (live_uri->port < 1024) {
2164                         ERR("Need to be root to use ports < 1024");
2165                         retval = -1;
2166                         goto exit_init_data;
2167                 }
2168         }
2169
2170         /* Setup the thread apps communication pipe. */
2171         if (create_conn_pipe()) {
2172                 retval = -1;
2173                 goto exit_init_data;
2174         }
2175
2176         /* Init relay command queue. */
2177         cds_wfcq_init(&viewer_conn_queue.head, &viewer_conn_queue.tail);
2178
2179         /* Set up max poll set size */
2180         if (lttng_poll_set_max_size()) {
2181                 retval = -1;
2182                 goto exit_init_data;
2183         }
2184
2185         /* Setup the dispatcher thread */
2186         ret = pthread_create(&live_dispatcher_thread, NULL,
2187                         thread_dispatcher, (void *) NULL);
2188         if (ret) {
2189                 errno = ret;
2190                 PERROR("pthread_create viewer dispatcher");
2191                 retval = -1;
2192                 goto exit_dispatcher_thread;
2193         }
2194
2195         /* Setup the worker thread */
2196         ret = pthread_create(&live_worker_thread, NULL,
2197                         thread_worker, NULL);
2198         if (ret) {
2199                 errno = ret;
2200                 PERROR("pthread_create viewer worker");
2201                 retval = -1;
2202                 goto exit_worker_thread;
2203         }
2204
2205         /* Setup the listener thread */
2206         ret = pthread_create(&live_listener_thread, NULL,
2207                         thread_listener, (void *) NULL);
2208         if (ret) {
2209                 errno = ret;
2210                 PERROR("pthread_create viewer listener");
2211                 retval = -1;
2212                 goto exit_listener_thread;
2213         }
2214
2215         /*
2216          * All OK, started all threads.
2217          */
2218         return retval;
2219
2220         /*
2221          * Join on the live_listener_thread should anything be added after
2222          * the live_listener thread's creation.
2223          */
2224
2225 exit_listener_thread:
2226
2227         ret = pthread_join(live_worker_thread, &status);
2228         if (ret) {
2229                 errno = ret;
2230                 PERROR("pthread_join live worker");
2231                 retval = -1;
2232         }
2233 exit_worker_thread:
2234
2235         ret = pthread_join(live_dispatcher_thread, &status);
2236         if (ret) {
2237                 errno = ret;
2238                 PERROR("pthread_join live dispatcher");
2239                 retval = -1;
2240         }
2241 exit_dispatcher_thread:
2242
2243 exit_init_data:
2244         cleanup_relayd_live();
2245
2246         return retval;
2247 }