src/bin/lttng-relayd/main.c

   1 /*
   2  * Copyright (C) 2012 - Julien Desfossez <jdesfossez@efficios.com>
   3  *                      David Goulet <dgoulet@efficios.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <getopt.h>
  21 #include <grp.h>
  22 #include <limits.h>
  23 #include <pthread.h>
  24 #include <signal.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <sys/mman.h>
  29 #include <sys/mount.h>
  30 #include <sys/resource.h>
  31 #include <sys/socket.h>
  32 #include <sys/stat.h>
  33 #include <sys/types.h>
  34 #include <sys/wait.h>
  35 #include <inttypes.h>
  36 #include <urcu/futex.h>
  37 #include <urcu/uatomic.h>
  38 #include <unistd.h>
  39 #include <fcntl.h>
  40 #include <config.h>
  41
  42 #include <lttng/lttng.h>
  43 #include <common/common.h>
  44 #include <common/compat/poll.h>
  45 #include <common/compat/socket.h>
  46 #include <common/defaults.h>
  47 #include <common/futex.h>
  48 #include <common/sessiond-comm/sessiond-comm.h>
  49 #include <common/sessiond-comm/inet.h>
  50 #include <common/hashtable/hashtable.h>
  51 #include <common/sessiond-comm/relayd.h>
  52 #include <common/uri.h>
  53 #include <common/utils.h>
  54
  55 #include "lttng-relayd.h"
  56
  57 /* command line options */
  58 static int opt_daemon;
  59 static char *opt_output_path;
  60 static struct lttng_uri *control_uri;
  61 static struct lttng_uri *data_uri;
  62
  63 const char *progname;
  64 static int is_root;                     /* Set to 1 if the daemon is running as root */
  65
  66 /*
  67  * Quit pipe for all threads. This permits a single cancellation point
  68  * for all threads when receiving an event on the pipe.
  69  */
  70 static int thread_quit_pipe[2] = { -1, -1 };
  71
  72 /*
  73  * This pipe is used to inform the worker thread that a command is queued and
  74  * ready to be processed.
  75  */
  76 static int relay_cmd_pipe[2] = { -1, -1 };
  77
  78 /* Shared between threads */
  79 static int dispatch_thread_exit;
  80
  81 static pthread_t listener_thread;
  82 static pthread_t dispatcher_thread;
  83 static pthread_t worker_thread;
  84
  85 static uint64_t last_relay_stream_id;
  86 static uint64_t last_relay_session_id;
  87
  88 /*
  89  * Relay command queue.
  90  *
  91  * The relay_thread_listener and relay_thread_dispatcher communicate with this
  92  * queue.
  93  */
  94 static struct relay_cmd_queue relay_cmd_queue;
  95
  96 /* buffer allocated at startup, used to store the trace data */
  97 static char *data_buffer;
  98 static unsigned int data_buffer_size;
  99
 100 /*
 101  * usage function on stderr
 102  */
 103 static
 104 void usage(void)
 105 {
 106         fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
 107         fprintf(stderr, "  -h, --help                         Display this usage.\n");
 108         fprintf(stderr, "  -d, --daemonize                    Start as a daemon.\n");
 109         fprintf(stderr, "  -C, --control-port                 Control port listening (URI)\n");
 110         fprintf(stderr, "  -D, --data-port                    Data port listening (URI)\n");
 111         fprintf(stderr, "  -o, --output                       Output path for traces (PATH)\n");
 112         fprintf(stderr, "  -v, --verbose                      Verbose mode. Activate DBG() macro.\n");
 113 }
 114
 115 static
 116 int parse_args(int argc, char **argv)
 117 {
 118         int c;
 119         int ret = 0;
 120         char *default_address;
 121
 122         static struct option long_options[] = {
 123                 { "control-port", 1, 0, 'C', },
 124                 { "data-port", 1, 0, 'D', },
 125                 { "daemonize", 0, 0, 'd', },
 126                 { "help", 0, 0, 'h', },
 127                 { "output", 1, 0, 'o', },
 128                 { "verbose", 0, 0, 'v', },
 129                 { NULL, 0, 0, 0, },
 130         };
 131
 132         while (1) {
 133                 int option_index = 0;
 134                 c = getopt_long(argc, argv, "dhv" "C:D:o:",
 135                                 long_options, &option_index);
 136                 if (c == -1) {
 137                         break;
 138                 }
 139
 140                 switch (c) {
 141                 case 0:
 142                         fprintf(stderr, "option %s", long_options[option_index].name);
 143                         if (optarg) {
 144                                 fprintf(stderr, " with arg %s\n", optarg);
 145                         }
 146                         break;
 147                 case 'C':
 148                         ret = uri_parse(optarg, &control_uri);
 149                         if (ret < 0) {
 150                                 ERR("Invalid control URI specified");
 151                                 goto exit;
 152                         }
 153                         if (control_uri->port == 0) {
 154                                 control_uri->port = DEFAULT_NETWORK_CONTROL_PORT;
 155                         }
 156                         break;
 157                 case 'D':
 158                         ret = uri_parse(optarg, &data_uri);
 159                         if (ret < 0) {
 160                                 ERR("Invalid data URI specified");
 161                                 goto exit;
 162                         }
 163                         if (data_uri->port == 0) {
 164                                 data_uri->port = DEFAULT_NETWORK_DATA_PORT;
 165                         }
 166                         break;
 167                 case 'd':
 168                         opt_daemon = 1;
 169                         break;
 170                 case 'h':
 171                         usage();
 172                         exit(EXIT_FAILURE);
 173                 case 'o':
 174                         ret = asprintf(&opt_output_path, "%s", optarg);
 175                         if (ret < 0) {
 176                                 PERROR("asprintf opt_output_path");
 177                                 goto exit;
 178                         }
 179                         break;
 180                 case 'v':
 181                         /* Verbose level can increase using multiple -v */
 182                         lttng_opt_verbose += 1;
 183                         break;
 184                 default:
 185                         /* Unknown option or other error.
 186                          * Error is printed by getopt, just return */
 187                         ret = -1;
 188                         goto exit;
 189                 }
 190         }
 191
 192         /* assign default values */
 193         if (control_uri == NULL) {
 194                 ret = asprintf(&default_address, "tcp://0.0.0.0:%d",
 195                                 DEFAULT_NETWORK_CONTROL_PORT);
 196                 if (ret < 0) {
 197                         PERROR("asprintf default data address");
 198                         goto exit;
 199                 }
 200
 201                 ret = uri_parse(default_address, &control_uri);
 202                 free(default_address);
 203                 if (ret < 0) {
 204                         ERR("Invalid control URI specified");
 205                         goto exit;
 206                 }
 207         }
 208         if (data_uri == NULL) {
 209                 ret = asprintf(&default_address, "tcp://0.0.0.0:%d",
 210                                 DEFAULT_NETWORK_DATA_PORT);
 211                 if (ret < 0) {
 212                         PERROR("asprintf default data address");
 213                         goto exit;
 214                 }
 215
 216                 ret = uri_parse(default_address, &data_uri);
 217                 free(default_address);
 218                 if (ret < 0) {
 219                         ERR("Invalid data URI specified");
 220                         goto exit;
 221                 }
 222         }
 223
 224 exit:
 225         return ret;
 226 }
 227
 228 /*
 229  * Cleanup the daemon
 230  */
 231 static
 232 void cleanup(void)
 233 {
 234         DBG("Cleaning up");
 235
 236         /* free the dynamically allocated opt_output_path */
 237         free(opt_output_path);
 238
 239         /* Close thread quit pipes */
 240         utils_close_pipe(thread_quit_pipe);
 241
 242         uri_free(control_uri);
 243         uri_free(data_uri);
 244 }
 245
 246 /*
 247  * Write to writable pipe used to notify a thread.
 248  */
 249 static
 250 int notify_thread_pipe(int wpipe)
 251 {
 252         int ret;
 253
 254         do {
 255                 ret = write(wpipe, "!", 1);
 256         } while (ret < 0 && errno == EINTR);
 257         if (ret < 0 || ret != 1) {
 258                 PERROR("write poll pipe");
 259         }
 260
 261         return ret;
 262 }
 263
 264 /*
 265  * Stop all threads by closing the thread quit pipe.
 266  */
 267 static
 268 void stop_threads(void)
 269 {
 270         int ret;
 271
 272         /* Stopping all threads */
 273         DBG("Terminating all threads");
 274         ret = notify_thread_pipe(thread_quit_pipe[1]);
 275         if (ret < 0) {
 276                 ERR("write error on thread quit pipe");
 277         }
 278
 279         /* Dispatch thread */
 280         CMM_STORE_SHARED(dispatch_thread_exit, 1);
 281         futex_nto1_wake(&relay_cmd_queue.futex);
 282 }
 283
 284 /*
 285  * Signal handler for the daemon
 286  *
 287  * Simply stop all worker threads, leaving main() return gracefully after
 288  * joining all threads and calling cleanup().
 289  */
 290 static
 291 void sighandler(int sig)
 292 {
 293         switch (sig) {
 294         case SIGPIPE:
 295                 DBG("SIGPIPE caught");
 296                 return;
 297         case SIGINT:
 298                 DBG("SIGINT caught");
 299                 stop_threads();
 300                 break;
 301         case SIGTERM:
 302                 DBG("SIGTERM caught");
 303                 stop_threads();
 304                 break;
 305         default:
 306                 break;
 307         }
 308 }
 309
 310 /*
 311  * Setup signal handler for :
 312  *              SIGINT, SIGTERM, SIGPIPE
 313  */
 314 static
 315 int set_signal_handler(void)
 316 {
 317         int ret = 0;
 318         struct sigaction sa;
 319         sigset_t sigset;
 320
 321         if ((ret = sigemptyset(&sigset)) < 0) {
 322                 PERROR("sigemptyset");
 323                 return ret;
 324         }
 325
 326         sa.sa_handler = sighandler;
 327         sa.sa_mask = sigset;
 328         sa.sa_flags = 0;
 329         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 330                 PERROR("sigaction");
 331                 return ret;
 332         }
 333
 334         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
 335                 PERROR("sigaction");
 336                 return ret;
 337         }
 338
 339         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
 340                 PERROR("sigaction");
 341                 return ret;
 342         }
 343
 344         DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
 345
 346         return ret;
 347 }
 348
 349 /*
 350  * Init thread quit pipe.
 351  *
 352  * Return -1 on error or 0 if all pipes are created.
 353  */
 354 static
 355 int init_thread_quit_pipe(void)
 356 {
 357         int ret;
 358
 359         ret = utils_create_pipe_cloexec(thread_quit_pipe);
 360
 361         return ret;
 362 }
 363
 364 /*
 365  * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
 366  */
 367 static
 368 int create_thread_poll_set(struct lttng_poll_event *events, int size)
 369 {
 370         int ret;
 371
 372         if (events == NULL || size == 0) {
 373                 ret = -1;
 374                 goto error;
 375         }
 376
 377         ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
 378         if (ret < 0) {
 379                 goto error;
 380         }
 381
 382         /* Add quit pipe */
 383         ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
 384         if (ret < 0) {
 385                 goto error;
 386         }
 387
 388         return 0;
 389
 390 error:
 391         return ret;
 392 }
 393
 394 /*
 395  * Check if the thread quit pipe was triggered.
 396  *
 397  * Return 1 if it was triggered else 0;
 398  */
 399 static
 400 int check_thread_quit_pipe(int fd, uint32_t events)
 401 {
 402         if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
 403                 return 1;
 404         }
 405
 406         return 0;
 407 }
 408
 409 /*
 410  * Create and init socket from uri.
 411  */
 412 static
 413 struct lttcomm_sock *relay_init_sock(struct lttng_uri *uri)
 414 {
 415         int ret;
 416         struct lttcomm_sock *sock = NULL;
 417
 418         sock = lttcomm_alloc_sock_from_uri(uri);
 419         if (sock == NULL) {
 420                 ERR("Allocating socket");
 421                 goto error;
 422         }
 423
 424         ret = lttcomm_create_sock(sock);
 425         if (ret < 0) {
 426                 goto error;
 427         }
 428         DBG("Listening on sock %d", sock->fd);
 429
 430         ret = sock->ops->bind(sock);
 431         if (ret < 0) {
 432                 goto error;
 433         }
 434
 435         ret = sock->ops->listen(sock, -1);
 436         if (ret < 0) {
 437                 goto error;
 438
 439         }
 440
 441         return sock;
 442
 443 error:
 444         if (sock) {
 445                 lttcomm_destroy_sock(sock);
 446         }
 447         return NULL;
 448 }
 449
 450 /*
 451  * Return nonzero if stream needs to be closed.
 452  */
 453 static
 454 int close_stream_check(struct relay_stream *stream)
 455 {
 456
 457         if (stream->close_flag && stream->prev_seq == stream->last_net_seq_num) {
 458                 /*
 459                  * We are about to close the stream so set the data pending flag to 1
 460                  * which will make the end data pending command skip the stream which
 461                  * is now closed and ready. Note that after proceeding to a file close,
 462                  * the written file is ready for reading.
 463                  */
 464                 stream->data_pending_check_done = 1;
 465                 return 1;
 466         }
 467         return 0;
 468 }
 469
 470 /*
 471  * This thread manages the listening for new connections on the network
 472  */
 473 static
 474 void *relay_thread_listener(void *data)
 475 {
 476         int i, ret, pollfd, err = -1;
 477         int val = 1;
 478         uint32_t revents, nb_fd;
 479         struct lttng_poll_event events;
 480         struct lttcomm_sock *control_sock, *data_sock;
 481
 482         DBG("[thread] Relay listener started");
 483
 484         control_sock = relay_init_sock(control_uri);
 485         if (!control_sock) {
 486                 goto error_sock_control;
 487         }
 488
 489         data_sock = relay_init_sock(data_uri);
 490         if (!data_sock) {
 491                 goto error_sock_relay;
 492         }
 493
 494         /*
 495          * Pass 3 as size here for the thread quit pipe, control and data socket.
 496          */
 497         ret = create_thread_poll_set(&events, 3);
 498         if (ret < 0) {
 499                 goto error_create_poll;
 500         }
 501
 502         /* Add the control socket */
 503         ret = lttng_poll_add(&events, control_sock->fd, LPOLLIN | LPOLLRDHUP);
 504         if (ret < 0) {
 505                 goto error_poll_add;
 506         }
 507
 508         /* Add the data socket */
 509         ret = lttng_poll_add(&events, data_sock->fd, LPOLLIN | LPOLLRDHUP);
 510         if (ret < 0) {
 511                 goto error_poll_add;
 512         }
 513
 514         while (1) {
 515                 DBG("Listener accepting connections");
 516
 517 restart:
 518                 ret = lttng_poll_wait(&events, -1);
 519                 if (ret < 0) {
 520                         /*
 521                          * Restart interrupted system call.
 522                          */
 523                         if (errno == EINTR) {
 524                                 goto restart;
 525                         }
 526                         goto error;
 527                 }
 528
 529                 nb_fd = ret;
 530
 531                 DBG("Relay new connection received");
 532                 for (i = 0; i < nb_fd; i++) {
 533                         /* Fetch once the poll data */
 534                         revents = LTTNG_POLL_GETEV(&events, i);
 535                         pollfd = LTTNG_POLL_GETFD(&events, i);
 536
 537                         /* Thread quit pipe has been closed. Killing thread. */
 538                         ret = check_thread_quit_pipe(pollfd, revents);
 539                         if (ret) {
 540                                 err = 0;
 541                                 goto exit;
 542                         }
 543
 544                         if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
 545                                 ERR("socket poll error");
 546                                 goto error;
 547                         } else if (revents & LPOLLIN) {
 548                                 /*
 549                                  * Get allocated in this thread,
 550                                  * enqueued to a global queue, dequeued
 551                                  * and freed in the worker thread.
 552                                  */
 553                                 struct relay_command *relay_cmd;
 554                                 struct lttcomm_sock *newsock;
 555
 556                                 relay_cmd = zmalloc(sizeof(struct relay_command));
 557                                 if (relay_cmd == NULL) {
 558                                         PERROR("relay command zmalloc");
 559                                         goto error;
 560                                 }
 561
 562                                 if (pollfd == data_sock->fd) {
 563                                         newsock = data_sock->ops->accept(data_sock);
 564                                         if (!newsock) {
 565                                                 PERROR("accepting data sock");
 566                                                 free(relay_cmd);
 567                                                 goto error;
 568                                         }
 569                                         relay_cmd->type = RELAY_DATA;
 570                                         DBG("Relay data connection accepted, socket %d", newsock->fd);
 571                                 } else {
 572                                         assert(pollfd == control_sock->fd);
 573                                         newsock = control_sock->ops->accept(control_sock);
 574                                         if (!newsock) {
 575                                                 PERROR("accepting control sock");
 576                                                 free(relay_cmd);
 577                                                 goto error;
 578                                         }
 579                                         relay_cmd->type = RELAY_CONTROL;
 580                                         DBG("Relay control connection accepted, socket %d", newsock->fd);
 581                                 }
 582                                 ret = setsockopt(newsock->fd, SOL_SOCKET, SO_REUSEADDR,
 583                                                 &val, sizeof(int));
 584                                 if (ret < 0) {
 585                                         PERROR("setsockopt inet");
 586                                         lttcomm_destroy_sock(newsock);
 587                                         free(relay_cmd);
 588                                         goto error;
 589                                 }
 590                                 relay_cmd->sock = newsock;
 591                                 /*
 592                                  * Lock free enqueue the request.
 593                                  */
 594                                 cds_wfq_enqueue(&relay_cmd_queue.queue, &relay_cmd->node);
 595
 596                                 /*
 597                                  * Wake the dispatch queue futex. Implicit memory
 598                                  * barrier with the exchange in cds_wfq_enqueue.
 599                                  */
 600                                 futex_nto1_wake(&relay_cmd_queue.futex);
 601                         }
 602                 }
 603         }
 604
 605 exit:
 606 error:
 607 error_poll_add:
 608         lttng_poll_clean(&events);
 609 error_create_poll:
 610         if (data_sock->fd >= 0) {
 611                 ret = data_sock->ops->close(data_sock);
 612                 if (ret) {
 613                         PERROR("close");
 614                 }
 615         }
 616         lttcomm_destroy_sock(data_sock);
 617 error_sock_relay:
 618         if (control_sock->fd >= 0) {
 619                 ret = control_sock->ops->close(control_sock);
 620                 if (ret) {
 621                         PERROR("close");
 622                 }
 623         }
 624         lttcomm_destroy_sock(control_sock);
 625 error_sock_control:
 626         if (err) {
 627                 DBG("Thread exited with error");
 628         }
 629         DBG("Relay listener thread cleanup complete");
 630         stop_threads();
 631         return NULL;
 632 }
 633
 634 /*
 635  * This thread manages the dispatching of the requests to worker threads
 636  */
 637 static
 638 void *relay_thread_dispatcher(void *data)
 639 {
 640         int ret;
 641         struct cds_wfq_node *node;
 642         struct relay_command *relay_cmd = NULL;
 643
 644         DBG("[thread] Relay dispatcher started");
 645
 646         while (!CMM_LOAD_SHARED(dispatch_thread_exit)) {
 647                 /* Atomically prepare the queue futex */
 648                 futex_nto1_prepare(&relay_cmd_queue.futex);
 649
 650                 do {
 651                         /* Dequeue commands */
 652                         node = cds_wfq_dequeue_blocking(&relay_cmd_queue.queue);
 653                         if (node == NULL) {
 654                                 DBG("Woken up but nothing in the relay command queue");
 655                                 /* Continue thread execution */
 656                                 break;
 657                         }
 658
 659                         relay_cmd = caa_container_of(node, struct relay_command, node);
 660                         DBG("Dispatching request waiting on sock %d", relay_cmd->sock->fd);
 661
 662                         /*
 663                          * Inform worker thread of the new request. This
 664                          * call is blocking so we can be assured that the data will be read
 665                          * at some point in time or wait to the end of the world :)
 666                          */
 667                         do {
 668                                 ret = write(relay_cmd_pipe[1], relay_cmd,
 669                                                 sizeof(struct relay_command));
 670                         } while (ret < 0 && errno == EINTR);
 671                         free(relay_cmd);
 672                         if (ret < 0 || ret != sizeof(struct relay_command)) {
 673                                 PERROR("write cmd pipe");
 674                                 goto error;
 675                         }
 676                 } while (node != NULL);
 677
 678                 /* Futex wait on queue. Blocking call on futex() */
 679                 futex_nto1_wait(&relay_cmd_queue.futex);
 680         }
 681
 682 error:
 683         DBG("Dispatch thread dying");
 684         stop_threads();
 685         return NULL;
 686 }
 687
 688 /*
 689  *  config_get_default_path
 690  *
 691  *  Returns the HOME directory path. Caller MUST NOT free(3) the return pointer.
 692  */
 693 static
 694 char *config_get_default_path(void)
 695 {
 696         return getenv("HOME");
 697 }
 698
 699 static
 700 char *create_output_path_auto(char *path_name)
 701 {
 702         int ret;
 703         char *traces_path = NULL;
 704         char *alloc_path = NULL;
 705         char *default_path;
 706
 707         default_path = config_get_default_path();
 708         if (default_path == NULL) {
 709                 ERR("Home path not found.\n \
 710                                 Please specify an output path using -o, --output PATH");
 711                 goto exit;
 712         }
 713         alloc_path = strdup(default_path);
 714         if (alloc_path == NULL) {
 715                 PERROR("Path allocation");
 716                 goto exit;
 717         }
 718         ret = asprintf(&traces_path, "%s/" DEFAULT_TRACE_DIR_NAME
 719                         "/%s", alloc_path, path_name);
 720         if (ret < 0) {
 721                 PERROR("asprintf trace dir name");
 722                 goto exit;
 723         }
 724 exit:
 725         free(alloc_path);
 726         return traces_path;
 727 }
 728
 729 static
 730 char *create_output_path_noauto(char *path_name)
 731 {
 732         int ret;
 733         char *traces_path = NULL;
 734         char *full_path;
 735
 736         full_path = utils_expand_path(opt_output_path);
 737         ret = asprintf(&traces_path, "%s/%s", full_path, path_name);
 738         if (ret < 0) {
 739                 PERROR("asprintf trace dir name");
 740                 goto exit;
 741         }
 742 exit:
 743         free(full_path);
 744         return traces_path;
 745 }
 746
 747 /*
 748  * create_output_path: create the output trace directory
 749  */
 750 static
 751 char *create_output_path(char *path_name)
 752 {
 753         if (opt_output_path == NULL) {
 754                 return create_output_path_auto(path_name);
 755         } else {
 756                 return create_output_path_noauto(path_name);
 757         }
 758 }
 759
 760 /*
 761  * Get stream from stream id.
 762  * Need to be called with RCU read-side lock held.
 763  */
 764 static
 765 struct relay_stream *relay_stream_from_stream_id(uint64_t stream_id,
 766                 struct lttng_ht *streams_ht)
 767 {
 768         struct lttng_ht_node_ulong *node;
 769         struct lttng_ht_iter iter;
 770         struct relay_stream *ret;
 771
 772         lttng_ht_lookup(streams_ht,
 773                         (void *)((unsigned long) stream_id),
 774                         &iter);
 775         node = lttng_ht_iter_get_node_ulong(&iter);
 776         if (node == NULL) {
 777                 DBG("Relay stream %" PRIu64 " not found", stream_id);
 778                 ret = NULL;
 779                 goto end;
 780         }
 781
 782         ret = caa_container_of(node, struct relay_stream, stream_n);
 783
 784 end:
 785         return ret;
 786 }
 787
 788 static
 789 void deferred_free_stream(struct rcu_head *head)
 790 {
 791         struct relay_stream *stream =
 792                 caa_container_of(head, struct relay_stream, rcu_node);
 793         free(stream);
 794 }
 795
 796 /*
 797  * relay_delete_session: Free all memory associated with a session and
 798  * close all the FDs
 799  */
 800 static
 801 void relay_delete_session(struct relay_command *cmd, struct lttng_ht *streams_ht)
 802 {
 803         struct lttng_ht_iter iter;
 804         struct lttng_ht_node_ulong *node;
 805         struct relay_stream *stream;
 806         int ret;
 807
 808         if (!cmd->session) {
 809                 return;
 810         }
 811
 812         DBG("Relay deleting session %" PRIu64, cmd->session->id);
 813
 814         rcu_read_lock();
 815         cds_lfht_for_each_entry(streams_ht->ht, &iter.iter, node, node) {
 816                 node = lttng_ht_iter_get_node_ulong(&iter);
 817                 if (node) {
 818                         stream = caa_container_of(node,
 819                                         struct relay_stream, stream_n);
 820                         if (stream->session == cmd->session) {
 821                                 ret = close(stream->fd);
 822                                 if (ret < 0) {
 823                                         PERROR("close stream fd on delete session");
 824                                 }
 825                                 ret = lttng_ht_del(streams_ht, &iter);
 826                                 assert(!ret);
 827                                 call_rcu(&stream->rcu_node,
 828                                         deferred_free_stream);
 829                         }
 830                 }
 831         }
 832         rcu_read_unlock();
 833
 834         free(cmd->session);
 835 }
 836
 837 /*
 838  * Handle the RELAYD_CREATE_SESSION command.
 839  *
 840  * On success, send back the session id or else return a negative value.
 841  */
 842 static
 843 int relay_create_session(struct lttcomm_relayd_hdr *recv_hdr,
 844                 struct relay_command *cmd)
 845 {
 846         int ret = 0, send_ret;
 847         struct relay_session *session;
 848         struct lttcomm_relayd_status_session reply;
 849
 850         assert(recv_hdr);
 851         assert(cmd);
 852
 853         memset(&reply, 0, sizeof(reply));
 854
 855         session = zmalloc(sizeof(struct relay_session));
 856         if (session == NULL) {
 857                 PERROR("relay session zmalloc");
 858                 ret = -1;
 859                 goto error;
 860         }
 861
 862         session->id = ++last_relay_session_id;
 863         session->sock = cmd->sock;
 864         cmd->session = session;
 865
 866         reply.session_id = htobe64(session->id);
 867
 868         DBG("Created session %" PRIu64, session->id);
 869
 870 error:
 871         if (ret < 0) {
 872                 reply.ret_code = htobe32(LTTNG_ERR_FATAL);
 873         } else {
 874                 reply.ret_code = htobe32(LTTNG_OK);
 875         }
 876
 877         send_ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
 878         if (send_ret < 0) {
 879                 ERR("Relayd sending session id");
 880                 ret = send_ret;
 881         }
 882
 883         return ret;
 884 }
 885
 886 /*
 887  * relay_add_stream: allocate a new stream for a session
 888  */
 889 static
 890 int relay_add_stream(struct lttcomm_relayd_hdr *recv_hdr,
 891                 struct relay_command *cmd, struct lttng_ht *streams_ht)
 892 {
 893         struct relay_session *session = cmd->session;
 894         struct lttcomm_relayd_add_stream stream_info;
 895         struct relay_stream *stream = NULL;
 896         struct lttcomm_relayd_status_stream reply;
 897         char *path = NULL, *root_path = NULL;
 898         int ret, send_ret;
 899
 900         if (!session || cmd->version_check_done == 0) {
 901                 ERR("Trying to add a stream before version check");
 902                 ret = -1;
 903                 goto end_no_session;
 904         }
 905
 906         ret = cmd->sock->ops->recvmsg(cmd->sock, &stream_info,
 907                         sizeof(struct lttcomm_relayd_add_stream), 0);
 908         if (ret < sizeof(struct lttcomm_relayd_add_stream)) {
 909                 if (ret == 0) {
 910                         /* Orderly shutdown. Not necessary to print an error. */
 911                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
 912                 } else {
 913                         ERR("Relay didn't receive valid add_stream struct size : %d", ret);
 914                 }
 915                 ret = -1;
 916                 goto end_no_session;
 917         }
 918         stream = zmalloc(sizeof(struct relay_stream));
 919         if (stream == NULL) {
 920                 PERROR("relay stream zmalloc");
 921                 ret = -1;
 922                 goto end_no_session;
 923         }
 924
 925         rcu_read_lock();
 926         stream->stream_handle = ++last_relay_stream_id;
 927         stream->prev_seq = -1ULL;
 928         stream->session = session;
 929
 930         root_path = create_output_path(stream_info.pathname);
 931         if (!root_path) {
 932                 ret = -1;
 933                 goto end;
 934         }
 935         ret = utils_mkdir_recursive(root_path, S_IRWXU | S_IRWXG);
 936         if (ret < 0) {
 937                 ERR("relay creating output directory");
 938                 goto end;
 939         }
 940
 941         ret = asprintf(&path, "%s/%s", root_path, stream_info.channel_name);
 942         if (ret < 0) {
 943                 PERROR("asprintf stream path");
 944                 path = NULL;
 945                 goto end;
 946         }
 947
 948         ret = open(path, O_WRONLY|O_CREAT|O_TRUNC, S_IRWXU|S_IRWXG|S_IRWXO);
 949         if (ret < 0) {
 950                 PERROR("Relay creating trace file");
 951                 goto end;
 952         }
 953
 954         stream->fd = ret;
 955         DBG("Tracefile %s created", path);
 956
 957         lttng_ht_node_init_ulong(&stream->stream_n,
 958                         (unsigned long) stream->stream_handle);
 959         lttng_ht_add_unique_ulong(streams_ht,
 960                         &stream->stream_n);
 961
 962         DBG("Relay new stream added %s", stream_info.channel_name);
 963
 964 end:
 965         free(path);
 966         free(root_path);
 967
 968         reply.handle = htobe64(stream->stream_handle);
 969         /* send the session id to the client or a negative return code on error */
 970         if (ret < 0) {
 971                 reply.ret_code = htobe32(LTTNG_ERR_UNK);
 972                 /* stream was not properly added to the ht, so free it */
 973                 free(stream);
 974         } else {
 975                 reply.ret_code = htobe32(LTTNG_OK);
 976         }
 977
 978         send_ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
 979                         sizeof(struct lttcomm_relayd_status_stream), 0);
 980         if (send_ret < 0) {
 981                 ERR("Relay sending stream id");
 982                 ret = send_ret;
 983         }
 984         rcu_read_unlock();
 985
 986 end_no_session:
 987         return ret;
 988 }
 989
 990 /*
 991  * relay_close_stream: close a specific stream
 992  */
 993 static
 994 int relay_close_stream(struct lttcomm_relayd_hdr *recv_hdr,
 995                 struct relay_command *cmd, struct lttng_ht *streams_ht)
 996 {
 997         struct relay_session *session = cmd->session;
 998         struct lttcomm_relayd_close_stream stream_info;
 999         struct lttcomm_relayd_generic_reply reply;
1000         struct relay_stream *stream;
1001         int ret, send_ret;
1002         struct lttng_ht_iter iter;
1003
1004         DBG("Close stream received");
1005
1006         if (!session || cmd->version_check_done == 0) {
1007                 ERR("Trying to close a stream before version check");
1008                 ret = -1;
1009                 goto end_no_session;
1010         }
1011
1012         ret = cmd->sock->ops->recvmsg(cmd->sock, &stream_info,
1013                         sizeof(struct lttcomm_relayd_close_stream), 0);
1014         if (ret < sizeof(struct lttcomm_relayd_close_stream)) {
1015                 if (ret == 0) {
1016                         /* Orderly shutdown. Not necessary to print an error. */
1017                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1018                 } else {
1019                         ERR("Relay didn't receive valid add_stream struct size : %d", ret);
1020                 }
1021                 ret = -1;
1022                 goto end_no_session;
1023         }
1024
1025         rcu_read_lock();
1026         stream = relay_stream_from_stream_id(be64toh(stream_info.stream_id),
1027                         streams_ht);
1028         if (!stream) {
1029                 ret = -1;
1030                 goto end_unlock;
1031         }
1032
1033         stream->last_net_seq_num = be64toh(stream_info.last_net_seq_num);
1034         stream->close_flag = 1;
1035
1036         if (close_stream_check(stream)) {
1037                 int delret;
1038
1039                 delret = close(stream->fd);
1040                 if (delret < 0) {
1041                         PERROR("close stream");
1042                 }
1043                 iter.iter.node = &stream->stream_n.node;
1044                 delret = lttng_ht_del(streams_ht, &iter);
1045                 assert(!delret);
1046                 call_rcu(&stream->rcu_node,
1047                                 deferred_free_stream);
1048                 DBG("Closed tracefile %d from close stream", stream->fd);
1049         }
1050
1051 end_unlock:
1052         rcu_read_unlock();
1053
1054         if (ret < 0) {
1055                 reply.ret_code = htobe32(LTTNG_ERR_UNK);
1056         } else {
1057                 reply.ret_code = htobe32(LTTNG_OK);
1058         }
1059         send_ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1060                         sizeof(struct lttcomm_relayd_generic_reply), 0);
1061         if (send_ret < 0) {
1062                 ERR("Relay sending stream id");
1063                 ret = send_ret;
1064         }
1065
1066 end_no_session:
1067         return ret;
1068 }
1069
1070 /*
1071  * relay_unknown_command: send -1 if received unknown command
1072  */
1073 static
1074 void relay_unknown_command(struct relay_command *cmd)
1075 {
1076         struct lttcomm_relayd_generic_reply reply;
1077         int ret;
1078
1079         reply.ret_code = htobe32(LTTNG_ERR_UNK);
1080         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1081                         sizeof(struct lttcomm_relayd_generic_reply), 0);
1082         if (ret < 0) {
1083                 ERR("Relay sending unknown command");
1084         }
1085 }
1086
1087 /*
1088  * relay_start: send an acknowledgment to the client to tell if we are
1089  * ready to receive data. We are ready if a session is established.
1090  */
1091 static
1092 int relay_start(struct lttcomm_relayd_hdr *recv_hdr,
1093                 struct relay_command *cmd)
1094 {
1095         int ret = htobe32(LTTNG_OK);
1096         struct lttcomm_relayd_generic_reply reply;
1097         struct relay_session *session = cmd->session;
1098
1099         if (!session) {
1100                 DBG("Trying to start the streaming without a session established");
1101                 ret = htobe32(LTTNG_ERR_UNK);
1102         }
1103
1104         reply.ret_code = ret;
1105         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1106                         sizeof(struct lttcomm_relayd_generic_reply), 0);
1107         if (ret < 0) {
1108                 ERR("Relay sending start ack");
1109         }
1110
1111         return ret;
1112 }
1113
1114 /*
1115  * Append padding to the file pointed by the file descriptor fd.
1116  */
1117 static int write_padding_to_file(int fd, uint32_t size)
1118 {
1119         int ret = 0;
1120         char *zeros;
1121
1122         if (size == 0) {
1123                 goto end;
1124         }
1125
1126         zeros = zmalloc(size);
1127         if (zeros == NULL) {
1128                 PERROR("zmalloc zeros for padding");
1129                 ret = -1;
1130                 goto end;
1131         }
1132
1133         do {
1134                 ret = write(fd, zeros, size);
1135         } while (ret < 0 && errno == EINTR);
1136         if (ret < 0 || ret != size) {
1137                 PERROR("write padding to file");
1138         }
1139
1140         free(zeros);
1141
1142 end:
1143         return ret;
1144 }
1145
1146 /*
1147  * relay_recv_metadata: receive the metada for the session.
1148  */
1149 static
1150 int relay_recv_metadata(struct lttcomm_relayd_hdr *recv_hdr,
1151                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1152 {
1153         int ret = htobe32(LTTNG_OK);
1154         struct relay_session *session = cmd->session;
1155         struct lttcomm_relayd_metadata_payload *metadata_struct;
1156         struct relay_stream *metadata_stream;
1157         uint64_t data_size, payload_size;
1158
1159         if (!session) {
1160                 ERR("Metadata sent before version check");
1161                 ret = -1;
1162                 goto end;
1163         }
1164
1165         data_size = payload_size = be64toh(recv_hdr->data_size);
1166         if (data_size < sizeof(struct lttcomm_relayd_metadata_payload)) {
1167                 ERR("Incorrect data size");
1168                 ret = -1;
1169                 goto end;
1170         }
1171         payload_size -= sizeof(struct lttcomm_relayd_metadata_payload);
1172
1173         if (data_buffer_size < data_size) {
1174                 /* In case the realloc fails, we can free the memory */
1175                 char *tmp_data_ptr;
1176
1177                 tmp_data_ptr = realloc(data_buffer, data_size);
1178                 if (!tmp_data_ptr) {
1179                         ERR("Allocating data buffer");
1180                         free(data_buffer);
1181                         ret = -1;
1182                         goto end;
1183                 }
1184                 data_buffer = tmp_data_ptr;
1185                 data_buffer_size = data_size;
1186         }
1187         memset(data_buffer, 0, data_size);
1188         DBG2("Relay receiving metadata, waiting for %" PRIu64 " bytes", data_size);
1189         ret = cmd->sock->ops->recvmsg(cmd->sock, data_buffer, data_size, 0);
1190         if (ret < 0 || ret != data_size) {
1191                 if (ret == 0) {
1192                         /* Orderly shutdown. Not necessary to print an error. */
1193                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1194                 } else {
1195                         ERR("Relay didn't receive the whole metadata");
1196                 }
1197                 ret = -1;
1198                 goto end;
1199         }
1200         metadata_struct = (struct lttcomm_relayd_metadata_payload *) data_buffer;
1201
1202         rcu_read_lock();
1203         metadata_stream = relay_stream_from_stream_id(
1204                         be64toh(metadata_struct->stream_id), streams_ht);
1205         if (!metadata_stream) {
1206                 ret = -1;
1207                 goto end_unlock;
1208         }
1209
1210         do {
1211                 ret = write(metadata_stream->fd, metadata_struct->payload,
1212                                 payload_size);
1213         } while (ret < 0 && errno == EINTR);
1214         if (ret < 0 || ret != payload_size) {
1215                 ERR("Relay error writing metadata on file");
1216                 ret = -1;
1217                 goto end_unlock;
1218         }
1219
1220         ret = write_padding_to_file(metadata_stream->fd,
1221                         be32toh(metadata_struct->padding_size));
1222         if (ret < 0) {
1223                 goto end_unlock;
1224         }
1225
1226         DBG2("Relay metadata written");
1227
1228 end_unlock:
1229         rcu_read_unlock();
1230 end:
1231         return ret;
1232 }
1233
1234 /*
1235  * relay_send_version: send relayd version number
1236  */
1237 static
1238 int relay_send_version(struct lttcomm_relayd_hdr *recv_hdr,
1239                 struct relay_command *cmd)
1240 {
1241         int ret;
1242         struct lttcomm_relayd_version reply, msg;
1243
1244         assert(cmd);
1245
1246         cmd->version_check_done = 1;
1247
1248         /* Get version from the other side. */
1249         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1250         if (ret < 0 || ret != sizeof(msg)) {
1251                 if (ret == 0) {
1252                         /* Orderly shutdown. Not necessary to print an error. */
1253                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1254                 } else {
1255                         ERR("Relay failed to receive the version values.");
1256                 }
1257                 ret = -1;
1258                 goto end;
1259         }
1260
1261         /*
1262          * For now, we just ignore the received version but after 2.1 stable
1263          * release, a check must be done to see if we either adapt to the other
1264          * side version (which MUST be lower than us) or keep the latest data
1265          * structure considering that the other side will adapt.
1266          */
1267
1268         ret = sscanf(VERSION, "%10u.%10u", &reply.major, &reply.minor);
1269         if (ret < 2) {
1270                 ERR("Error in scanning version");
1271                 ret = -1;
1272                 goto end;
1273         }
1274         reply.major = htobe32(reply.major);
1275         reply.minor = htobe32(reply.minor);
1276         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1277                         sizeof(struct lttcomm_relayd_version), 0);
1278         if (ret < 0) {
1279                 ERR("Relay sending version");
1280         }
1281         DBG("Version check done (%u.%u)", be32toh(reply.major),
1282                         be32toh(reply.minor));
1283
1284 end:
1285         return ret;
1286 }
1287
1288 /*
1289  * Check for data pending for a given stream id from the session daemon.
1290  */
1291 static
1292 int relay_data_pending(struct lttcomm_relayd_hdr *recv_hdr,
1293                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1294 {
1295         struct relay_session *session = cmd->session;
1296         struct lttcomm_relayd_data_pending msg;
1297         struct lttcomm_relayd_generic_reply reply;
1298         struct relay_stream *stream;
1299         int ret;
1300         uint64_t last_net_seq_num, stream_id;
1301
1302         DBG("Data pending command received");
1303
1304         if (!session || cmd->version_check_done == 0) {
1305                 ERR("Trying to check for data before version check");
1306                 ret = -1;
1307                 goto end_no_session;
1308         }
1309
1310         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1311         if (ret < sizeof(msg)) {
1312                 if (ret == 0) {
1313                         /* Orderly shutdown. Not necessary to print an error. */
1314                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1315                 } else {
1316                         ERR("Relay didn't receive valid data_pending struct size : %d",
1317                                         ret);
1318                 }
1319                 ret = -1;
1320                 goto end_no_session;
1321         }
1322
1323         stream_id = be64toh(msg.stream_id);
1324         last_net_seq_num = be64toh(msg.last_net_seq_num);
1325
1326         rcu_read_lock();
1327         stream = relay_stream_from_stream_id(stream_id, streams_ht);
1328         if (stream == NULL) {
1329                 ret = -1;
1330                 goto end_unlock;
1331         }
1332
1333         DBG("Data pending for stream id %" PRIu64 " prev_seq %" PRIu64
1334                         " and last_seq %" PRIu64, stream_id, stream->prev_seq,
1335                         last_net_seq_num);
1336
1337         /* Avoid wrapping issue */
1338         if (((int64_t) (stream->prev_seq - last_net_seq_num)) >= 0) {
1339                 /* Data has in fact been written and is NOT pending */
1340                 ret = 0;
1341         } else {
1342                 /* Data still being streamed thus pending */
1343                 ret = 1;
1344         }
1345
1346         /* Pending check is now done. */
1347         stream->data_pending_check_done = 1;
1348
1349 end_unlock:
1350         rcu_read_unlock();
1351
1352         reply.ret_code = htobe32(ret);
1353         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1354         if (ret < 0) {
1355                 ERR("Relay data pending ret code failed");
1356         }
1357
1358 end_no_session:
1359         return ret;
1360 }
1361
1362 /*
1363  * Wait for the control socket to reach a quiescent state.
1364  *
1365  * Note that for now, when receiving this command from the session daemon, this
1366  * means that every subsequent commands or data received on the control socket
1367  * has been handled. So, this is why we simply return OK here.
1368  */
1369 static
1370 int relay_quiescent_control(struct lttcomm_relayd_hdr *recv_hdr,
1371                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1372 {
1373         int ret;
1374         uint64_t stream_id;
1375         struct relay_stream *stream;
1376         struct lttng_ht_iter iter;
1377         struct lttcomm_relayd_quiescent_control msg;
1378         struct lttcomm_relayd_generic_reply reply;
1379
1380         DBG("Checking quiescent state on control socket");
1381
1382         if (!cmd->session || cmd->version_check_done == 0) {
1383                 ERR("Trying to check for data before version check");
1384                 ret = -1;
1385                 goto end_no_session;
1386         }
1387
1388         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1389         if (ret < sizeof(msg)) {
1390                 if (ret == 0) {
1391                         /* Orderly shutdown. Not necessary to print an error. */
1392                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1393                 } else {
1394                         ERR("Relay didn't receive valid begin data_pending struct size: %d",
1395                                         ret);
1396                 }
1397                 ret = -1;
1398                 goto end_no_session;
1399         }
1400
1401         stream_id = be64toh(msg.stream_id);
1402
1403         rcu_read_lock();
1404         cds_lfht_for_each_entry(streams_ht->ht, &iter.iter, stream, stream_n.node) {
1405                 if (stream->stream_handle == stream_id) {
1406                         stream->data_pending_check_done = 1;
1407                         DBG("Relay quiescent control pending flag set to %" PRIu64,
1408                                         stream_id);
1409                         break;
1410                 }
1411         }
1412         rcu_read_unlock();
1413
1414         reply.ret_code = htobe32(LTTNG_OK);
1415         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1416         if (ret < 0) {
1417                 ERR("Relay data quiescent control ret code failed");
1418         }
1419
1420 end_no_session:
1421         return ret;
1422 }
1423
1424 /*
1425  * Initialize a data pending command. This means that a client is about to ask
1426  * for data pending for each stream he/she holds. Simply iterate over all
1427  * streams of a session and set the data_pending_check_done flag.
1428  *
1429  * This command returns to the client a LTTNG_OK code.
1430  */
1431 static
1432 int relay_begin_data_pending(struct lttcomm_relayd_hdr *recv_hdr,
1433                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1434 {
1435         int ret;
1436         struct lttng_ht_iter iter;
1437         struct lttcomm_relayd_begin_data_pending msg;
1438         struct lttcomm_relayd_generic_reply reply;
1439         struct relay_stream *stream;
1440         uint64_t session_id;
1441
1442         assert(recv_hdr);
1443         assert(cmd);
1444         assert(streams_ht);
1445
1446         DBG("Init streams for data pending");
1447
1448         if (!cmd->session || cmd->version_check_done == 0) {
1449                 ERR("Trying to check for data before version check");
1450                 ret = -1;
1451                 goto end_no_session;
1452         }
1453
1454         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1455         if (ret < sizeof(msg)) {
1456                 if (ret == 0) {
1457                         /* Orderly shutdown. Not necessary to print an error. */
1458                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1459                 } else {
1460                         ERR("Relay didn't receive valid begin data_pending struct size: %d",
1461                                         ret);
1462                 }
1463                 ret = -1;
1464                 goto end_no_session;
1465         }
1466
1467         session_id = be64toh(msg.session_id);
1468
1469         /*
1470          * Iterate over all streams to set the begin data pending flag. For now, the
1471          * streams are indexed by stream handle so we have to iterate over all
1472          * streams to find the one associated with the right session_id.
1473          */
1474         rcu_read_lock();
1475         cds_lfht_for_each_entry(streams_ht->ht, &iter.iter, stream, stream_n.node) {
1476                 if (stream->session->id == session_id) {
1477                         stream->data_pending_check_done = 0;
1478                         DBG("Set begin data pending flag to stream %" PRIu64,
1479                                         stream->stream_handle);
1480                 }
1481         }
1482         rcu_read_unlock();
1483
1484         /* All good, send back reply. */
1485         reply.ret_code = htobe32(LTTNG_OK);
1486
1487         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1488         if (ret < 0) {
1489                 ERR("Relay begin data pending send reply failed");
1490         }
1491
1492 end_no_session:
1493         return ret;
1494 }
1495
1496 /*
1497  * End data pending command. This will check, for a given session id, if each
1498  * stream associated with it has its data_pending_check_done flag set. If not,
1499  * this means that the client lost track of the stream but the data is still
1500  * being streamed on our side. In this case, we inform the client that data is
1501  * inflight.
1502  *
1503  * Return to the client if there is data in flight or not with a ret_code.
1504  */
1505 static
1506 int relay_end_data_pending(struct lttcomm_relayd_hdr *recv_hdr,
1507                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1508 {
1509         int ret;
1510         struct lttng_ht_iter iter;
1511         struct lttcomm_relayd_end_data_pending msg;
1512         struct lttcomm_relayd_generic_reply reply;
1513         struct relay_stream *stream;
1514         uint64_t session_id;
1515         uint32_t is_data_inflight = 0;
1516
1517         assert(recv_hdr);
1518         assert(cmd);
1519         assert(streams_ht);
1520
1521         DBG("End data pending command");
1522
1523         if (!cmd->session || cmd->version_check_done == 0) {
1524                 ERR("Trying to check for data before version check");
1525                 ret = -1;
1526                 goto end_no_session;
1527         }
1528
1529         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1530         if (ret < sizeof(msg)) {
1531                 if (ret == 0) {
1532                         /* Orderly shutdown. Not necessary to print an error. */
1533                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1534                 } else {
1535                         ERR("Relay didn't receive valid end data_pending struct size: %d",
1536                                         ret);
1537                 }
1538                 ret = -1;
1539                 goto end_no_session;
1540         }
1541
1542         session_id = be64toh(msg.session_id);
1543
1544         /* Iterate over all streams to see if the begin data pending flag is set. */
1545         rcu_read_lock();
1546         cds_lfht_for_each_entry(streams_ht->ht, &iter.iter, stream, stream_n.node) {
1547                 if (stream->session->id == session_id &&
1548                                 !stream->data_pending_check_done) {
1549                         is_data_inflight = 1;
1550                         DBG("Data is still in flight for stream %" PRIu64,
1551                                         stream->stream_handle);
1552                         break;
1553                 }
1554         }
1555         rcu_read_unlock();
1556
1557         /* All good, send back reply. */
1558         reply.ret_code = htobe32(is_data_inflight);
1559
1560         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1561         if (ret < 0) {
1562                 ERR("Relay end data pending send reply failed");
1563         }
1564
1565 end_no_session:
1566         return ret;
1567 }
1568
1569 /*
1570  * relay_process_control: Process the commands received on the control socket
1571  */
1572 static
1573 int relay_process_control(struct lttcomm_relayd_hdr *recv_hdr,
1574                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1575 {
1576         int ret = 0;
1577
1578         switch (be32toh(recv_hdr->cmd)) {
1579         case RELAYD_CREATE_SESSION:
1580                 ret = relay_create_session(recv_hdr, cmd);
1581                 break;
1582         case RELAYD_ADD_STREAM:
1583                 ret = relay_add_stream(recv_hdr, cmd, streams_ht);
1584                 break;
1585         case RELAYD_START_DATA:
1586                 ret = relay_start(recv_hdr, cmd);
1587                 break;
1588         case RELAYD_SEND_METADATA:
1589                 ret = relay_recv_metadata(recv_hdr, cmd, streams_ht);
1590                 break;
1591         case RELAYD_VERSION:
1592                 ret = relay_send_version(recv_hdr, cmd);
1593                 break;
1594         case RELAYD_CLOSE_STREAM:
1595                 ret = relay_close_stream(recv_hdr, cmd, streams_ht);
1596                 break;
1597         case RELAYD_DATA_PENDING:
1598                 ret = relay_data_pending(recv_hdr, cmd, streams_ht);
1599                 break;
1600         case RELAYD_QUIESCENT_CONTROL:
1601                 ret = relay_quiescent_control(recv_hdr, cmd, streams_ht);
1602                 break;
1603         case RELAYD_BEGIN_DATA_PENDING:
1604                 ret = relay_begin_data_pending(recv_hdr, cmd, streams_ht);
1605                 break;
1606         case RELAYD_END_DATA_PENDING:
1607                 ret = relay_end_data_pending(recv_hdr, cmd, streams_ht);
1608                 break;
1609         case RELAYD_UPDATE_SYNC_INFO:
1610         default:
1611                 ERR("Received unknown command (%u)", be32toh(recv_hdr->cmd));
1612                 relay_unknown_command(cmd);
1613                 ret = -1;
1614                 goto end;
1615         }
1616
1617 end:
1618         return ret;
1619 }
1620
1621 /*
1622  * relay_process_data: Process the data received on the data socket
1623  */
1624 static
1625 int relay_process_data(struct relay_command *cmd, struct lttng_ht *streams_ht)
1626 {
1627         int ret = 0;
1628         struct relay_stream *stream;
1629         struct lttcomm_relayd_data_hdr data_hdr;
1630         uint64_t stream_id;
1631         uint64_t net_seq_num;
1632         uint32_t data_size;
1633
1634         ret = cmd->sock->ops->recvmsg(cmd->sock, &data_hdr,
1635                         sizeof(struct lttcomm_relayd_data_hdr), 0);
1636         if (ret <= 0) {
1637                 if (ret == 0) {
1638                         /* Orderly shutdown. Not necessary to print an error. */
1639                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1640                 } else {
1641                         ERR("Unable to receive data header on sock %d", cmd->sock->fd);
1642                 }
1643                 ret = -1;
1644                 goto end;
1645         }
1646
1647         stream_id = be64toh(data_hdr.stream_id);
1648
1649         rcu_read_lock();
1650         stream = relay_stream_from_stream_id(stream_id, streams_ht);
1651         if (!stream) {
1652                 ret = -1;
1653                 goto end_unlock;
1654         }
1655
1656         data_size = be32toh(data_hdr.data_size);
1657         if (data_buffer_size < data_size) {
1658                 char *tmp_data_ptr;
1659
1660                 tmp_data_ptr = realloc(data_buffer, data_size);
1661                 if (!tmp_data_ptr) {
1662                         ERR("Allocating data buffer");
1663                         free(data_buffer);
1664                         ret = -1;
1665                         goto end_unlock;
1666                 }
1667                 data_buffer = tmp_data_ptr;
1668                 data_buffer_size = data_size;
1669         }
1670         memset(data_buffer, 0, data_size);
1671
1672         net_seq_num = be64toh(data_hdr.net_seq_num);
1673
1674         DBG3("Receiving data of size %u for stream id %" PRIu64 " seqnum %" PRIu64,
1675                 data_size, stream_id, net_seq_num);
1676         ret = cmd->sock->ops->recvmsg(cmd->sock, data_buffer, data_size, 0);
1677         if (ret <= 0) {
1678                 if (ret == 0) {
1679                         /* Orderly shutdown. Not necessary to print an error. */
1680                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1681                 }
1682                 ret = -1;
1683                 goto end_unlock;
1684         }
1685
1686         do {
1687                 ret = write(stream->fd, data_buffer, data_size);
1688         } while (ret < 0 && errno == EINTR);
1689         if (ret < 0 || ret != data_size) {
1690                 ERR("Relay error writing data to file");
1691                 ret = -1;
1692                 goto end_unlock;
1693         }
1694
1695         DBG2("Relay wrote %d bytes to tracefile for stream id %" PRIu64,
1696                         ret, stream->stream_handle);
1697
1698         ret = write_padding_to_file(stream->fd, be32toh(data_hdr.padding_size));
1699         if (ret < 0) {
1700                 goto end_unlock;
1701         }
1702
1703         stream->prev_seq = net_seq_num;
1704
1705         /* Check if we need to close the FD */
1706         if (close_stream_check(stream)) {
1707                 int cret;
1708                 struct lttng_ht_iter iter;
1709
1710                 cret = close(stream->fd);
1711                 if (cret < 0) {
1712                         PERROR("close stream process data");
1713                 }
1714                 iter.iter.node = &stream->stream_n.node;
1715                 ret = lttng_ht_del(streams_ht, &iter);
1716                 assert(!ret);
1717                 call_rcu(&stream->rcu_node,
1718                         deferred_free_stream);
1719                 DBG("Closed tracefile %d after recv data", stream->fd);
1720         }
1721
1722 end_unlock:
1723         rcu_read_unlock();
1724 end:
1725         return ret;
1726 }
1727
1728 static
1729 void relay_cleanup_poll_connection(struct lttng_poll_event *events, int pollfd)
1730 {
1731         int ret;
1732
1733         lttng_poll_del(events, pollfd);
1734
1735         ret = close(pollfd);
1736         if (ret < 0) {
1737                 ERR("Closing pollfd %d", pollfd);
1738         }
1739 }
1740
1741 static
1742 int relay_add_connection(int fd, struct lttng_poll_event *events,
1743                 struct lttng_ht *relay_connections_ht)
1744 {
1745         struct relay_command *relay_connection;
1746         int ret;
1747
1748         relay_connection = zmalloc(sizeof(struct relay_command));
1749         if (relay_connection == NULL) {
1750                 PERROR("Relay command zmalloc");
1751                 goto error;
1752         }
1753         do {
1754                 ret = read(fd, relay_connection, sizeof(struct relay_command));
1755         } while (ret < 0 && errno == EINTR);
1756         if (ret < 0 || ret < sizeof(struct relay_command)) {
1757                 PERROR("read relay cmd pipe");
1758                 goto error_read;
1759         }
1760
1761         lttng_ht_node_init_ulong(&relay_connection->sock_n,
1762                         (unsigned long) relay_connection->sock->fd);
1763         rcu_read_lock();
1764         lttng_ht_add_unique_ulong(relay_connections_ht,
1765                         &relay_connection->sock_n);
1766         rcu_read_unlock();
1767         return lttng_poll_add(events,
1768                         relay_connection->sock->fd,
1769                         LPOLLIN | LPOLLRDHUP);
1770
1771 error_read:
1772         free(relay_connection);
1773 error:
1774         return -1;
1775 }
1776
1777 static
1778 void deferred_free_connection(struct rcu_head *head)
1779 {
1780         struct relay_command *relay_connection =
1781                 caa_container_of(head, struct relay_command, rcu_node);
1782
1783         lttcomm_destroy_sock(relay_connection->sock);
1784         free(relay_connection);
1785 }
1786
1787 static
1788 void relay_del_connection(struct lttng_ht *relay_connections_ht,
1789                 struct lttng_ht *streams_ht, struct lttng_ht_iter *iter,
1790                 struct relay_command *relay_connection)
1791 {
1792         int ret;
1793
1794         ret = lttng_ht_del(relay_connections_ht, iter);
1795         assert(!ret);
1796         if (relay_connection->type == RELAY_CONTROL) {
1797                 relay_delete_session(relay_connection, streams_ht);
1798         }
1799
1800         call_rcu(&relay_connection->rcu_node,
1801                 deferred_free_connection);
1802 }
1803
1804 /*
1805  * This thread does the actual work
1806  */
1807 static
1808 void *relay_thread_worker(void *data)
1809 {
1810         int ret, err = -1, last_seen_data_fd = -1;
1811         uint32_t nb_fd;
1812         struct relay_command *relay_connection;
1813         struct lttng_poll_event events;
1814         struct lttng_ht *relay_connections_ht;
1815         struct lttng_ht_node_ulong *node;
1816         struct lttng_ht_iter iter;
1817         struct lttng_ht *streams_ht;
1818         struct lttcomm_relayd_hdr recv_hdr;
1819
1820         DBG("[thread] Relay worker started");
1821
1822         rcu_register_thread();
1823
1824         /* table of connections indexed on socket */
1825         relay_connections_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1826         if (!relay_connections_ht) {
1827                 goto relay_connections_ht_error;
1828         }
1829
1830         /* tables of streams indexed by stream ID */
1831         streams_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1832         if (!streams_ht) {
1833                 goto streams_ht_error;
1834         }
1835
1836         ret = create_thread_poll_set(&events, 2);
1837         if (ret < 0) {
1838                 goto error_poll_create;
1839         }
1840
1841         ret = lttng_poll_add(&events, relay_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1842         if (ret < 0) {
1843                 goto error;
1844         }
1845
1846 restart:
1847         while (1) {
1848                 int idx = -1, i, seen_control = 0, last_notdel_data_fd = -1;
1849
1850                 /* Infinite blocking call, waiting for transmission */
1851                 DBG3("Relayd worker thread polling...");
1852                 ret = lttng_poll_wait(&events, -1);
1853                 if (ret < 0) {
1854                         /*
1855                          * Restart interrupted system call.
1856                          */
1857                         if (errno == EINTR) {
1858                                 goto restart;
1859                         }
1860                         goto error;
1861                 }
1862
1863                 nb_fd = ret;
1864
1865                 /*
1866                  * Process control. The control connection is prioritised so we don't
1867                  * starve it with high throughout put tracing data on the data
1868                  * connection.
1869                  */
1870                 for (i = 0; i < nb_fd; i++) {
1871                         /* Fetch once the poll data */
1872                         uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1873                         int pollfd = LTTNG_POLL_GETFD(&events, i);
1874
1875                         /* Thread quit pipe has been closed. Killing thread. */
1876                         ret = check_thread_quit_pipe(pollfd, revents);
1877                         if (ret) {
1878                                 err = 0;
1879                                 goto exit;
1880                         }
1881
1882                         /* Inspect the relay cmd pipe for new connection */
1883                         if (pollfd == relay_cmd_pipe[0]) {
1884                                 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1885                                         ERR("Relay pipe error");
1886                                         goto error;
1887                                 } else if (revents & LPOLLIN) {
1888                                         DBG("Relay command received");
1889                                         ret = relay_add_connection(relay_cmd_pipe[0],
1890                                                         &events, relay_connections_ht);
1891                                         if (ret < 0) {
1892                                                 goto error;
1893                                         }
1894                                 }
1895                         } else if (revents) {
1896                                 rcu_read_lock();
1897                                 lttng_ht_lookup(relay_connections_ht,
1898                                                 (void *)((unsigned long) pollfd),
1899                                                 &iter);
1900                                 node = lttng_ht_iter_get_node_ulong(&iter);
1901                                 if (node == NULL) {
1902                                         DBG2("Relay sock %d not found", pollfd);
1903                                         rcu_read_unlock();
1904                                         goto error;
1905                                 }
1906                                 relay_connection = caa_container_of(node,
1907                                                 struct relay_command, sock_n);
1908
1909                                 if (revents & (LPOLLERR)) {
1910                                         ERR("POLL ERROR");
1911                                         relay_cleanup_poll_connection(&events, pollfd);
1912                                         relay_del_connection(relay_connections_ht,
1913                                                         streams_ht, &iter,
1914                                                         relay_connection);
1915                                         if (last_seen_data_fd == pollfd) {
1916                                                 last_seen_data_fd = last_notdel_data_fd;
1917                                         }
1918                                 } else if (revents & (LPOLLHUP | LPOLLRDHUP)) {
1919                                         DBG("Socket %d hung up", pollfd);
1920                                         relay_cleanup_poll_connection(&events, pollfd);
1921                                         relay_del_connection(relay_connections_ht,
1922                                                         streams_ht, &iter,
1923                                                         relay_connection);
1924                                         if (last_seen_data_fd == pollfd) {
1925                                                 last_seen_data_fd = last_notdel_data_fd;
1926                                         }
1927                                 } else if (revents & LPOLLIN) {
1928                                         /* control socket */
1929                                         if (relay_connection->type == RELAY_CONTROL) {
1930                                                 ret = relay_connection->sock->ops->recvmsg(
1931                                                                 relay_connection->sock, &recv_hdr,
1932                                                                 sizeof(struct lttcomm_relayd_hdr), 0);
1933                                                 /* connection closed */
1934                                                 if (ret <= 0) {
1935                                                         relay_cleanup_poll_connection(&events, pollfd);
1936                                                         relay_del_connection(relay_connections_ht,
1937                                                                         streams_ht, &iter,
1938                                                                         relay_connection);
1939                                                         DBG("Control connection closed with %d", pollfd);
1940                                                 } else {
1941                                                         if (relay_connection->session) {
1942                                                                 DBG2("Relay worker receiving data for session : %" PRIu64,
1943                                                                                 relay_connection->session->id);
1944                                                         }
1945                                                         ret = relay_process_control(&recv_hdr,
1946                                                                         relay_connection,
1947                                                                         streams_ht);
1948                                                         if (ret < 0) {
1949                                                                 /* Clear the session on error. */
1950                                                                 relay_cleanup_poll_connection(&events, pollfd);
1951                                                                 relay_del_connection(relay_connections_ht,
1952                                                                                 streams_ht, &iter,
1953                                                                                 relay_connection);
1954                                                                 DBG("Connection closed with %d", pollfd);
1955                                                         }
1956                                                         seen_control = 1;
1957                                                 }
1958                                         } else {
1959                                                 /*
1960                                                  * Flag the last seen data fd not deleted. It will be
1961                                                  * used as the last seen fd if any fd gets deleted in
1962                                                  * this first loop.
1963                                                  */
1964                                                 last_notdel_data_fd = pollfd;
1965                                         }
1966                                 }
1967                                 rcu_read_unlock();
1968                         }
1969                 }
1970
1971                 /*
1972                  * The last loop handled a control request, go back to poll to make
1973                  * sure we prioritise the control socket.
1974                  */
1975                 if (seen_control) {
1976                         continue;
1977                 }
1978
1979                 if (last_seen_data_fd >= 0) {
1980                         for (i = 0; i < nb_fd; i++) {
1981                                 int pollfd = LTTNG_POLL_GETFD(&events, i);
1982                                 if (last_seen_data_fd == pollfd) {
1983                                         idx = i;
1984                                         break;
1985                                 }
1986                         }
1987                 }
1988
1989                 /* Process data connection. */
1990                 for (i = idx + 1; i < nb_fd; i++) {
1991                         /* Fetch the poll data. */
1992                         uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1993                         int pollfd = LTTNG_POLL_GETFD(&events, i);
1994
1995                         /* Skip the command pipe. It's handled in the first loop. */
1996                         if (pollfd == relay_cmd_pipe[0]) {
1997                                 continue;
1998                         }
1999
2000                         if (revents) {
2001                                 rcu_read_lock();
2002                                 lttng_ht_lookup(relay_connections_ht,
2003                                                 (void *)((unsigned long) pollfd),
2004                                                 &iter);
2005                                 node = lttng_ht_iter_get_node_ulong(&iter);
2006                                 if (node == NULL) {
2007                                         /* Skip it. Might be removed before. */
2008                                         rcu_read_unlock();
2009                                         continue;
2010                                 }
2011                                 relay_connection = caa_container_of(node,
2012                                                 struct relay_command, sock_n);
2013
2014                                 if (revents & LPOLLIN) {
2015                                         if (relay_connection->type != RELAY_DATA) {
2016                                                 continue;
2017                                         }
2018
2019                                         ret = relay_process_data(relay_connection, streams_ht);
2020                                         /* connection closed */
2021                                         if (ret < 0) {
2022                                                 relay_cleanup_poll_connection(&events, pollfd);
2023                                                 relay_del_connection(relay_connections_ht,
2024                                                                 streams_ht, &iter,
2025                                                                 relay_connection);
2026                                                 DBG("Data connection closed with %d", pollfd);
2027                                                 /*
2028                                                  * Every goto restart call sets the last seen fd where
2029                                                  * here we don't really care since we gracefully
2030                                                  * continue the loop after the connection is deleted.
2031                                                  */
2032                                         } else {
2033                                                 /* Keep last seen port. */
2034                                                 last_seen_data_fd = pollfd;
2035                                                 rcu_read_unlock();
2036                                                 goto restart;
2037                                         }
2038                                 }
2039                                 rcu_read_unlock();
2040                         }
2041                 }
2042                 last_seen_data_fd = -1;
2043         }
2044
2045 exit:
2046 error:
2047         lttng_poll_clean(&events);
2048
2049         /* empty the hash table and free the memory */
2050         rcu_read_lock();
2051         cds_lfht_for_each_entry(relay_connections_ht->ht, &iter.iter, node, node) {
2052                 node = lttng_ht_iter_get_node_ulong(&iter);
2053                 if (node) {
2054                         relay_connection = caa_container_of(node,
2055                                         struct relay_command, sock_n);
2056                         relay_del_connection(relay_connections_ht,
2057                                         streams_ht, &iter,
2058                                         relay_connection);
2059                 }
2060         }
2061         rcu_read_unlock();
2062 error_poll_create:
2063         lttng_ht_destroy(streams_ht);
2064 streams_ht_error:
2065         lttng_ht_destroy(relay_connections_ht);
2066 relay_connections_ht_error:
2067         /* Close relay cmd pipes */
2068         utils_close_pipe(relay_cmd_pipe);
2069         if (err) {
2070                 DBG("Thread exited with error");
2071         }
2072         DBG("Worker thread cleanup complete");
2073         free(data_buffer);
2074         stop_threads();
2075         rcu_unregister_thread();
2076         return NULL;
2077 }
2078
2079 /*
2080  * Create the relay command pipe to wake thread_manage_apps.
2081  * Closed in cleanup().
2082  */
2083 static int create_relay_cmd_pipe(void)
2084 {
2085         int ret;
2086
2087         ret = utils_create_pipe_cloexec(relay_cmd_pipe);
2088
2089         return ret;
2090 }
2091
2092 /*
2093  * main
2094  */
2095 int main(int argc, char **argv)
2096 {
2097         int ret = 0;
2098         void *status;
2099
2100         /* Create thread quit pipe */
2101         if ((ret = init_thread_quit_pipe()) < 0) {
2102                 goto error;
2103         }
2104
2105         /* Parse arguments */
2106         progname = argv[0];
2107         if ((ret = parse_args(argc, argv)) < 0) {
2108                 goto exit;
2109         }
2110
2111         if ((ret = set_signal_handler()) < 0) {
2112                 goto exit;
2113         }
2114
2115         /* Try to create directory if -o, --output is specified. */
2116         if (opt_output_path) {
2117                 ret = utils_mkdir_recursive(opt_output_path, S_IRWXU | S_IRWXG);
2118                 if (ret < 0) {
2119                         ERR("Unable to create %s", opt_output_path);
2120                         goto exit;
2121                 }
2122         }
2123
2124         /* Daemonize */
2125         if (opt_daemon) {
2126                 ret = daemon(0, 0);
2127                 if (ret < 0) {
2128                         PERROR("daemon");
2129                         goto exit;
2130                 }
2131         }
2132
2133         /* Check if daemon is UID = 0 */
2134         is_root = !getuid();
2135
2136         if (!is_root) {
2137                 if (control_uri->port < 1024 || data_uri->port < 1024) {
2138                         ERR("Need to be root to use ports < 1024");
2139                         ret = -1;
2140                         goto exit;
2141                 }
2142         }
2143
2144         /* Setup the thread apps communication pipe. */
2145         if ((ret = create_relay_cmd_pipe()) < 0) {
2146                 goto exit;
2147         }
2148
2149         /* Init relay command queue. */
2150         cds_wfq_init(&relay_cmd_queue.queue);
2151
2152         /* Set up max poll set size */
2153         lttng_poll_set_max_size();
2154
2155         /* Setup the dispatcher thread */
2156         ret = pthread_create(&dispatcher_thread, NULL,
2157                         relay_thread_dispatcher, (void *) NULL);
2158         if (ret != 0) {
2159                 PERROR("pthread_create dispatcher");
2160                 goto exit_dispatcher;
2161         }
2162
2163         /* Setup the worker thread */
2164         ret = pthread_create(&worker_thread, NULL,
2165                         relay_thread_worker, (void *) NULL);
2166         if (ret != 0) {
2167                 PERROR("pthread_create worker");
2168                 goto exit_worker;
2169         }
2170
2171         /* Setup the listener thread */
2172         ret = pthread_create(&listener_thread, NULL,
2173                         relay_thread_listener, (void *) NULL);
2174         if (ret != 0) {
2175                 PERROR("pthread_create listener");
2176                 goto exit_listener;
2177         }
2178
2179 exit_listener:
2180         ret = pthread_join(listener_thread, &status);
2181         if (ret != 0) {
2182                 PERROR("pthread_join");
2183                 goto error;     /* join error, exit without cleanup */
2184         }
2185
2186 exit_worker:
2187         ret = pthread_join(worker_thread, &status);
2188         if (ret != 0) {
2189                 PERROR("pthread_join");
2190                 goto error;     /* join error, exit without cleanup */
2191         }
2192
2193 exit_dispatcher:
2194         ret = pthread_join(dispatcher_thread, &status);
2195         if (ret != 0) {
2196                 PERROR("pthread_join");
2197                 goto error;     /* join error, exit without cleanup */
2198         }
2199
2200 exit:
2201         cleanup();
2202         if (!ret) {
2203                 exit(EXIT_SUCCESS);
2204         }
2205
2206 error:
2207         exit(EXIT_FAILURE);
2208 }