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                 goto end;
 945         }
 946
 947         ret = open(path, O_WRONLY|O_CREAT|O_TRUNC, S_IRWXU|S_IRWXG|S_IRWXO);
 948         if (ret < 0) {
 949                 PERROR("Relay creating trace file");
 950                 goto end;
 951         }
 952
 953         stream->fd = ret;
 954         DBG("Tracefile %s created", path);
 955
 956         lttng_ht_node_init_ulong(&stream->stream_n,
 957                         (unsigned long) stream->stream_handle);
 958         lttng_ht_add_unique_ulong(streams_ht,
 959                         &stream->stream_n);
 960
 961         DBG("Relay new stream added %s", stream_info.channel_name);
 962
 963 end:
 964         free(path);
 965         free(root_path);
 966         /* send the session id to the client or a negative return code on error */
 967         if (ret < 0) {
 968                 reply.ret_code = htobe32(LTTNG_ERR_UNK);
 969         } else {
 970                 reply.ret_code = htobe32(LTTNG_OK);
 971         }
 972         reply.handle = htobe64(stream->stream_handle);
 973         send_ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
 974                         sizeof(struct lttcomm_relayd_status_stream), 0);
 975         if (send_ret < 0) {
 976                 ERR("Relay sending stream id");
 977                 ret = send_ret;
 978         }
 979         rcu_read_unlock();
 980
 981 end_no_session:
 982         return ret;
 983 }
 984
 985 /*
 986  * relay_close_stream: close a specific stream
 987  */
 988 static
 989 int relay_close_stream(struct lttcomm_relayd_hdr *recv_hdr,
 990                 struct relay_command *cmd, struct lttng_ht *streams_ht)
 991 {
 992         struct relay_session *session = cmd->session;
 993         struct lttcomm_relayd_close_stream stream_info;
 994         struct lttcomm_relayd_generic_reply reply;
 995         struct relay_stream *stream;
 996         int ret, send_ret;
 997         struct lttng_ht_iter iter;
 998
 999         DBG("Close stream received");
1000
1001         if (!session || cmd->version_check_done == 0) {
1002                 ERR("Trying to close a stream before version check");
1003                 ret = -1;
1004                 goto end_no_session;
1005         }
1006
1007         ret = cmd->sock->ops->recvmsg(cmd->sock, &stream_info,
1008                         sizeof(struct lttcomm_relayd_close_stream), 0);
1009         if (ret < sizeof(struct lttcomm_relayd_close_stream)) {
1010                 if (ret == 0) {
1011                         /* Orderly shutdown. Not necessary to print an error. */
1012                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1013                 } else {
1014                         ERR("Relay didn't receive valid add_stream struct size : %d", ret);
1015                 }
1016                 ret = -1;
1017                 goto end_no_session;
1018         }
1019
1020         rcu_read_lock();
1021         stream = relay_stream_from_stream_id(be64toh(stream_info.stream_id),
1022                         streams_ht);
1023         if (!stream) {
1024                 ret = -1;
1025                 goto end_unlock;
1026         }
1027
1028         stream->last_net_seq_num = be64toh(stream_info.last_net_seq_num);
1029         stream->close_flag = 1;
1030
1031         if (close_stream_check(stream)) {
1032                 int delret;
1033
1034                 delret = close(stream->fd);
1035                 if (delret < 0) {
1036                         PERROR("close stream");
1037                 }
1038                 iter.iter.node = &stream->stream_n.node;
1039                 delret = lttng_ht_del(streams_ht, &iter);
1040                 assert(!delret);
1041                 call_rcu(&stream->rcu_node,
1042                                 deferred_free_stream);
1043                 DBG("Closed tracefile %d from close stream", stream->fd);
1044         }
1045
1046 end_unlock:
1047         rcu_read_unlock();
1048
1049         if (ret < 0) {
1050                 reply.ret_code = htobe32(LTTNG_ERR_UNK);
1051         } else {
1052                 reply.ret_code = htobe32(LTTNG_OK);
1053         }
1054         send_ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1055                         sizeof(struct lttcomm_relayd_generic_reply), 0);
1056         if (send_ret < 0) {
1057                 ERR("Relay sending stream id");
1058                 ret = send_ret;
1059         }
1060
1061 end_no_session:
1062         return ret;
1063 }
1064
1065 /*
1066  * relay_unknown_command: send -1 if received unknown command
1067  */
1068 static
1069 void relay_unknown_command(struct relay_command *cmd)
1070 {
1071         struct lttcomm_relayd_generic_reply reply;
1072         int ret;
1073
1074         reply.ret_code = htobe32(LTTNG_ERR_UNK);
1075         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1076                         sizeof(struct lttcomm_relayd_generic_reply), 0);
1077         if (ret < 0) {
1078                 ERR("Relay sending unknown command");
1079         }
1080 }
1081
1082 /*
1083  * relay_start: send an acknowledgment to the client to tell if we are
1084  * ready to receive data. We are ready if a session is established.
1085  */
1086 static
1087 int relay_start(struct lttcomm_relayd_hdr *recv_hdr,
1088                 struct relay_command *cmd)
1089 {
1090         int ret = htobe32(LTTNG_OK);
1091         struct lttcomm_relayd_generic_reply reply;
1092         struct relay_session *session = cmd->session;
1093
1094         if (!session) {
1095                 DBG("Trying to start the streaming without a session established");
1096                 ret = htobe32(LTTNG_ERR_UNK);
1097         }
1098
1099         reply.ret_code = ret;
1100         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1101                         sizeof(struct lttcomm_relayd_generic_reply), 0);
1102         if (ret < 0) {
1103                 ERR("Relay sending start ack");
1104         }
1105
1106         return ret;
1107 }
1108
1109 /*
1110  * Append padding to the file pointed by the file descriptor fd.
1111  */
1112 static int write_padding_to_file(int fd, uint32_t size)
1113 {
1114         int ret = 0;
1115         char *zeros;
1116
1117         if (size == 0) {
1118                 goto end;
1119         }
1120
1121         zeros = zmalloc(size);
1122         if (zeros == NULL) {
1123                 PERROR("zmalloc zeros for padding");
1124                 ret = -1;
1125                 goto end;
1126         }
1127
1128         do {
1129                 ret = write(fd, zeros, size);
1130         } while (ret < 0 && errno == EINTR);
1131         if (ret < 0 || ret != size) {
1132                 PERROR("write padding to file");
1133         }
1134
1135         free(zeros);
1136
1137 end:
1138         return ret;
1139 }
1140
1141 /*
1142  * relay_recv_metadata: receive the metada for the session.
1143  */
1144 static
1145 int relay_recv_metadata(struct lttcomm_relayd_hdr *recv_hdr,
1146                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1147 {
1148         int ret = htobe32(LTTNG_OK);
1149         struct relay_session *session = cmd->session;
1150         struct lttcomm_relayd_metadata_payload *metadata_struct;
1151         struct relay_stream *metadata_stream;
1152         uint64_t data_size, payload_size;
1153
1154         if (!session) {
1155                 ERR("Metadata sent before version check");
1156                 ret = -1;
1157                 goto end;
1158         }
1159
1160         data_size = payload_size = be64toh(recv_hdr->data_size);
1161         if (data_size < sizeof(struct lttcomm_relayd_metadata_payload)) {
1162                 ERR("Incorrect data size");
1163                 ret = -1;
1164                 goto end;
1165         }
1166         payload_size -= sizeof(struct lttcomm_relayd_metadata_payload);
1167
1168         if (data_buffer_size < data_size) {
1169                 /* In case the realloc fails, we can free the memory */
1170                 char *tmp_data_ptr;
1171
1172                 tmp_data_ptr = realloc(data_buffer, data_size);
1173                 if (!tmp_data_ptr) {
1174                         ERR("Allocating data buffer");
1175                         free(data_buffer);
1176                         ret = -1;
1177                         goto end;
1178                 }
1179                 data_buffer = tmp_data_ptr;
1180                 data_buffer_size = data_size;
1181         }
1182         memset(data_buffer, 0, data_size);
1183         DBG2("Relay receiving metadata, waiting for %" PRIu64 " bytes", data_size);
1184         ret = cmd->sock->ops->recvmsg(cmd->sock, data_buffer, data_size, 0);
1185         if (ret < 0 || ret != data_size) {
1186                 if (ret == 0) {
1187                         /* Orderly shutdown. Not necessary to print an error. */
1188                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1189                 } else {
1190                         ERR("Relay didn't receive the whole metadata");
1191                 }
1192                 ret = -1;
1193                 goto end;
1194         }
1195         metadata_struct = (struct lttcomm_relayd_metadata_payload *) data_buffer;
1196
1197         rcu_read_lock();
1198         metadata_stream = relay_stream_from_stream_id(
1199                         be64toh(metadata_struct->stream_id), streams_ht);
1200         if (!metadata_stream) {
1201                 ret = -1;
1202                 goto end_unlock;
1203         }
1204
1205         do {
1206                 ret = write(metadata_stream->fd, metadata_struct->payload,
1207                                 payload_size);
1208         } while (ret < 0 && errno == EINTR);
1209         if (ret < 0 || ret != payload_size) {
1210                 ERR("Relay error writing metadata on file");
1211                 ret = -1;
1212                 goto end_unlock;
1213         }
1214
1215         ret = write_padding_to_file(metadata_stream->fd,
1216                         be32toh(metadata_struct->padding_size));
1217         if (ret < 0) {
1218                 goto end_unlock;
1219         }
1220
1221         DBG2("Relay metadata written");
1222
1223 end_unlock:
1224         rcu_read_unlock();
1225 end:
1226         return ret;
1227 }
1228
1229 /*
1230  * relay_send_version: send relayd version number
1231  */
1232 static
1233 int relay_send_version(struct lttcomm_relayd_hdr *recv_hdr,
1234                 struct relay_command *cmd)
1235 {
1236         int ret;
1237         struct lttcomm_relayd_version reply, msg;
1238
1239         assert(cmd);
1240
1241         cmd->version_check_done = 1;
1242
1243         /* Get version from the other side. */
1244         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1245         if (ret < 0 || ret != sizeof(msg)) {
1246                 if (ret == 0) {
1247                         /* Orderly shutdown. Not necessary to print an error. */
1248                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1249                 } else {
1250                         ERR("Relay failed to receive the version values.");
1251                 }
1252                 ret = -1;
1253                 goto end;
1254         }
1255
1256         /*
1257          * For now, we just ignore the received version but after 2.1 stable
1258          * release, a check must be done to see if we either adapt to the other
1259          * side version (which MUST be lower than us) or keep the latest data
1260          * structure considering that the other side will adapt.
1261          */
1262
1263         ret = sscanf(VERSION, "%10u.%10u", &reply.major, &reply.minor);
1264         if (ret < 2) {
1265                 ERR("Error in scanning version");
1266                 ret = -1;
1267                 goto end;
1268         }
1269         reply.major = htobe32(reply.major);
1270         reply.minor = htobe32(reply.minor);
1271         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply,
1272                         sizeof(struct lttcomm_relayd_version), 0);
1273         if (ret < 0) {
1274                 ERR("Relay sending version");
1275         }
1276         DBG("Version check done (%u.%u)", be32toh(reply.major),
1277                         be32toh(reply.minor));
1278
1279 end:
1280         return ret;
1281 }
1282
1283 /*
1284  * Check for data pending for a given stream id from the session daemon.
1285  */
1286 static
1287 int relay_data_pending(struct lttcomm_relayd_hdr *recv_hdr,
1288                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1289 {
1290         struct relay_session *session = cmd->session;
1291         struct lttcomm_relayd_data_pending msg;
1292         struct lttcomm_relayd_generic_reply reply;
1293         struct relay_stream *stream;
1294         int ret;
1295         uint64_t last_net_seq_num, stream_id;
1296
1297         DBG("Data pending command received");
1298
1299         if (!session || cmd->version_check_done == 0) {
1300                 ERR("Trying to check for data before version check");
1301                 ret = -1;
1302                 goto end_no_session;
1303         }
1304
1305         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1306         if (ret < sizeof(msg)) {
1307                 if (ret == 0) {
1308                         /* Orderly shutdown. Not necessary to print an error. */
1309                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1310                 } else {
1311                         ERR("Relay didn't receive valid data_pending struct size : %d",
1312                                         ret);
1313                 }
1314                 ret = -1;
1315                 goto end_no_session;
1316         }
1317
1318         stream_id = be64toh(msg.stream_id);
1319         last_net_seq_num = be64toh(msg.last_net_seq_num);
1320
1321         rcu_read_lock();
1322         stream = relay_stream_from_stream_id(stream_id, streams_ht);
1323         if (stream == NULL) {
1324                 ret = -1;
1325                 goto end_unlock;
1326         }
1327
1328         DBG("Data pending for stream id %" PRIu64 " prev_seq %" PRIu64
1329                         " and last_seq %" PRIu64, stream_id, stream->prev_seq,
1330                         last_net_seq_num);
1331
1332         /* Avoid wrapping issue */
1333         if (((int64_t) (stream->prev_seq - last_net_seq_num)) >= 0) {
1334                 /* Data has in fact been written and is NOT pending */
1335                 ret = 0;
1336         } else {
1337                 /* Data still being streamed thus pending */
1338                 ret = 1;
1339         }
1340
1341         /* Pending check is now done. */
1342         stream->data_pending_check_done = 1;
1343
1344 end_unlock:
1345         rcu_read_unlock();
1346
1347         reply.ret_code = htobe32(ret);
1348         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1349         if (ret < 0) {
1350                 ERR("Relay data pending ret code failed");
1351         }
1352
1353 end_no_session:
1354         return ret;
1355 }
1356
1357 /*
1358  * Wait for the control socket to reach a quiescent state.
1359  *
1360  * Note that for now, when receiving this command from the session daemon, this
1361  * means that every subsequent commands or data received on the control socket
1362  * has been handled. So, this is why we simply return OK here.
1363  */
1364 static
1365 int relay_quiescent_control(struct lttcomm_relayd_hdr *recv_hdr,
1366                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1367 {
1368         int ret;
1369         uint64_t stream_id;
1370         struct relay_stream *stream;
1371         struct lttng_ht_iter iter;
1372         struct lttcomm_relayd_quiescent_control msg;
1373         struct lttcomm_relayd_generic_reply reply;
1374
1375         DBG("Checking quiescent state on control socket");
1376
1377         if (!cmd->session || cmd->version_check_done == 0) {
1378                 ERR("Trying to check for data before version check");
1379                 ret = -1;
1380                 goto end_no_session;
1381         }
1382
1383         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1384         if (ret < sizeof(msg)) {
1385                 if (ret == 0) {
1386                         /* Orderly shutdown. Not necessary to print an error. */
1387                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1388                 } else {
1389                         ERR("Relay didn't receive valid begin data_pending struct size: %d",
1390                                         ret);
1391                 }
1392                 ret = -1;
1393                 goto end_no_session;
1394         }
1395
1396         stream_id = be64toh(msg.stream_id);
1397
1398         rcu_read_lock();
1399         cds_lfht_for_each_entry(streams_ht->ht, &iter.iter, stream, stream_n.node) {
1400                 if (stream->stream_handle == stream_id) {
1401                         stream->data_pending_check_done = 1;
1402                         DBG("Relay quiescent control pending flag set to %" PRIu64,
1403                                         stream_id);
1404                         break;
1405                 }
1406         }
1407         rcu_read_unlock();
1408
1409         reply.ret_code = htobe32(LTTNG_OK);
1410         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1411         if (ret < 0) {
1412                 ERR("Relay data quiescent control ret code failed");
1413         }
1414
1415 end_no_session:
1416         return ret;
1417 }
1418
1419 /*
1420  * Initialize a data pending command. This means that a client is about to ask
1421  * for data pending for each stream he/she holds. Simply iterate over all
1422  * streams of a session and set the data_pending_check_done flag.
1423  *
1424  * This command returns to the client a LTTNG_OK code.
1425  */
1426 static
1427 int relay_begin_data_pending(struct lttcomm_relayd_hdr *recv_hdr,
1428                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1429 {
1430         int ret;
1431         struct lttng_ht_iter iter;
1432         struct lttcomm_relayd_begin_data_pending msg;
1433         struct lttcomm_relayd_generic_reply reply;
1434         struct relay_stream *stream;
1435         uint64_t session_id;
1436
1437         assert(recv_hdr);
1438         assert(cmd);
1439         assert(streams_ht);
1440
1441         DBG("Init streams for data pending");
1442
1443         if (!cmd->session || cmd->version_check_done == 0) {
1444                 ERR("Trying to check for data before version check");
1445                 ret = -1;
1446                 goto end_no_session;
1447         }
1448
1449         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1450         if (ret < sizeof(msg)) {
1451                 if (ret == 0) {
1452                         /* Orderly shutdown. Not necessary to print an error. */
1453                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1454                 } else {
1455                         ERR("Relay didn't receive valid begin data_pending struct size: %d",
1456                                         ret);
1457                 }
1458                 ret = -1;
1459                 goto end_no_session;
1460         }
1461
1462         session_id = be64toh(msg.session_id);
1463
1464         /*
1465          * Iterate over all streams to set the begin data pending flag. For now, the
1466          * streams are indexed by stream handle so we have to iterate over all
1467          * streams to find the one associated with the right session_id.
1468          */
1469         rcu_read_lock();
1470         cds_lfht_for_each_entry(streams_ht->ht, &iter.iter, stream, stream_n.node) {
1471                 if (stream->session->id == session_id) {
1472                         stream->data_pending_check_done = 0;
1473                         DBG("Set begin data pending flag to stream %" PRIu64,
1474                                         stream->stream_handle);
1475                 }
1476         }
1477         rcu_read_unlock();
1478
1479         /* All good, send back reply. */
1480         reply.ret_code = htobe32(LTTNG_OK);
1481
1482         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1483         if (ret < 0) {
1484                 ERR("Relay begin data pending send reply failed");
1485         }
1486
1487 end_no_session:
1488         return ret;
1489 }
1490
1491 /*
1492  * End data pending command. This will check, for a given session id, if each
1493  * stream associated with it has its data_pending_check_done flag set. If not,
1494  * this means that the client lost track of the stream but the data is still
1495  * being streamed on our side. In this case, we inform the client that data is
1496  * inflight.
1497  *
1498  * Return to the client if there is data in flight or not with a ret_code.
1499  */
1500 static
1501 int relay_end_data_pending(struct lttcomm_relayd_hdr *recv_hdr,
1502                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1503 {
1504         int ret;
1505         struct lttng_ht_iter iter;
1506         struct lttcomm_relayd_end_data_pending msg;
1507         struct lttcomm_relayd_generic_reply reply;
1508         struct relay_stream *stream;
1509         uint64_t session_id;
1510         uint32_t is_data_inflight = 0;
1511
1512         assert(recv_hdr);
1513         assert(cmd);
1514         assert(streams_ht);
1515
1516         DBG("End data pending command");
1517
1518         if (!cmd->session || cmd->version_check_done == 0) {
1519                 ERR("Trying to check for data before version check");
1520                 ret = -1;
1521                 goto end_no_session;
1522         }
1523
1524         ret = cmd->sock->ops->recvmsg(cmd->sock, &msg, sizeof(msg), 0);
1525         if (ret < sizeof(msg)) {
1526                 if (ret == 0) {
1527                         /* Orderly shutdown. Not necessary to print an error. */
1528                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1529                 } else {
1530                         ERR("Relay didn't receive valid end data_pending struct size: %d",
1531                                         ret);
1532                 }
1533                 ret = -1;
1534                 goto end_no_session;
1535         }
1536
1537         session_id = be64toh(msg.session_id);
1538
1539         /* Iterate over all streams to see if the begin data pending flag is set. */
1540         rcu_read_lock();
1541         cds_lfht_for_each_entry(streams_ht->ht, &iter.iter, stream, stream_n.node) {
1542                 if (stream->session->id == session_id &&
1543                                 !stream->data_pending_check_done) {
1544                         is_data_inflight = 1;
1545                         DBG("Data is still in flight for stream %" PRIu64,
1546                                         stream->stream_handle);
1547                         break;
1548                 }
1549         }
1550         rcu_read_unlock();
1551
1552         /* All good, send back reply. */
1553         reply.ret_code = htobe32(is_data_inflight);
1554
1555         ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
1556         if (ret < 0) {
1557                 ERR("Relay end data pending send reply failed");
1558         }
1559
1560 end_no_session:
1561         return ret;
1562 }
1563
1564 /*
1565  * relay_process_control: Process the commands received on the control socket
1566  */
1567 static
1568 int relay_process_control(struct lttcomm_relayd_hdr *recv_hdr,
1569                 struct relay_command *cmd, struct lttng_ht *streams_ht)
1570 {
1571         int ret = 0;
1572
1573         switch (be32toh(recv_hdr->cmd)) {
1574         case RELAYD_CREATE_SESSION:
1575                 ret = relay_create_session(recv_hdr, cmd);
1576                 break;
1577         case RELAYD_ADD_STREAM:
1578                 ret = relay_add_stream(recv_hdr, cmd, streams_ht);
1579                 break;
1580         case RELAYD_START_DATA:
1581                 ret = relay_start(recv_hdr, cmd);
1582                 break;
1583         case RELAYD_SEND_METADATA:
1584                 ret = relay_recv_metadata(recv_hdr, cmd, streams_ht);
1585                 break;
1586         case RELAYD_VERSION:
1587                 ret = relay_send_version(recv_hdr, cmd);
1588                 break;
1589         case RELAYD_CLOSE_STREAM:
1590                 ret = relay_close_stream(recv_hdr, cmd, streams_ht);
1591                 break;
1592         case RELAYD_DATA_PENDING:
1593                 ret = relay_data_pending(recv_hdr, cmd, streams_ht);
1594                 break;
1595         case RELAYD_QUIESCENT_CONTROL:
1596                 ret = relay_quiescent_control(recv_hdr, cmd, streams_ht);
1597                 break;
1598         case RELAYD_BEGIN_DATA_PENDING:
1599                 ret = relay_begin_data_pending(recv_hdr, cmd, streams_ht);
1600                 break;
1601         case RELAYD_END_DATA_PENDING:
1602                 ret = relay_end_data_pending(recv_hdr, cmd, streams_ht);
1603                 break;
1604         case RELAYD_UPDATE_SYNC_INFO:
1605         default:
1606                 ERR("Received unknown command (%u)", be32toh(recv_hdr->cmd));
1607                 relay_unknown_command(cmd);
1608                 ret = -1;
1609                 goto end;
1610         }
1611
1612 end:
1613         return ret;
1614 }
1615
1616 /*
1617  * relay_process_data: Process the data received on the data socket
1618  */
1619 static
1620 int relay_process_data(struct relay_command *cmd, struct lttng_ht *streams_ht)
1621 {
1622         int ret = 0;
1623         struct relay_stream *stream;
1624         struct lttcomm_relayd_data_hdr data_hdr;
1625         uint64_t stream_id;
1626         uint64_t net_seq_num;
1627         uint32_t data_size;
1628
1629         ret = cmd->sock->ops->recvmsg(cmd->sock, &data_hdr,
1630                         sizeof(struct lttcomm_relayd_data_hdr), 0);
1631         if (ret <= 0) {
1632                 if (ret == 0) {
1633                         /* Orderly shutdown. Not necessary to print an error. */
1634                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1635                 } else {
1636                         ERR("Unable to receive data header on sock %d", cmd->sock->fd);
1637                 }
1638                 ret = -1;
1639                 goto end;
1640         }
1641
1642         stream_id = be64toh(data_hdr.stream_id);
1643
1644         rcu_read_lock();
1645         stream = relay_stream_from_stream_id(stream_id, streams_ht);
1646         if (!stream) {
1647                 ret = -1;
1648                 goto end_unlock;
1649         }
1650
1651         data_size = be32toh(data_hdr.data_size);
1652         if (data_buffer_size < data_size) {
1653                 char *tmp_data_ptr;
1654
1655                 tmp_data_ptr = realloc(data_buffer, data_size);
1656                 if (!tmp_data_ptr) {
1657                         ERR("Allocating data buffer");
1658                         free(data_buffer);
1659                         ret = -1;
1660                         goto end_unlock;
1661                 }
1662                 data_buffer = tmp_data_ptr;
1663                 data_buffer_size = data_size;
1664         }
1665         memset(data_buffer, 0, data_size);
1666
1667         net_seq_num = be64toh(data_hdr.net_seq_num);
1668
1669         DBG3("Receiving data of size %u for stream id %" PRIu64 " seqnum %" PRIu64,
1670                 data_size, stream_id, net_seq_num);
1671         ret = cmd->sock->ops->recvmsg(cmd->sock, data_buffer, data_size, 0);
1672         if (ret <= 0) {
1673                 if (ret == 0) {
1674                         /* Orderly shutdown. Not necessary to print an error. */
1675                         DBG("Socket %d did an orderly shutdown", cmd->sock->fd);
1676                 }
1677                 ret = -1;
1678                 goto end_unlock;
1679         }
1680
1681         do {
1682                 ret = write(stream->fd, data_buffer, data_size);
1683         } while (ret < 0 && errno == EINTR);
1684         if (ret < 0 || ret != data_size) {
1685                 ERR("Relay error writing data to file");
1686                 ret = -1;
1687                 goto end_unlock;
1688         }
1689
1690         DBG2("Relay wrote %d bytes to tracefile for stream id %" PRIu64,
1691                         ret, stream->stream_handle);
1692
1693         ret = write_padding_to_file(stream->fd, be32toh(data_hdr.padding_size));
1694         if (ret < 0) {
1695                 goto end_unlock;
1696         }
1697
1698         stream->prev_seq = net_seq_num;
1699
1700         /* Check if we need to close the FD */
1701         if (close_stream_check(stream)) {
1702                 int cret;
1703                 struct lttng_ht_iter iter;
1704
1705                 cret = close(stream->fd);
1706                 if (cret < 0) {
1707                         PERROR("close stream process data");
1708                 }
1709                 iter.iter.node = &stream->stream_n.node;
1710                 ret = lttng_ht_del(streams_ht, &iter);
1711                 assert(!ret);
1712                 call_rcu(&stream->rcu_node,
1713                         deferred_free_stream);
1714                 DBG("Closed tracefile %d after recv data", stream->fd);
1715         }
1716
1717 end_unlock:
1718         rcu_read_unlock();
1719 end:
1720         return ret;
1721 }
1722
1723 static
1724 void relay_cleanup_poll_connection(struct lttng_poll_event *events, int pollfd)
1725 {
1726         int ret;
1727
1728         lttng_poll_del(events, pollfd);
1729
1730         ret = close(pollfd);
1731         if (ret < 0) {
1732                 ERR("Closing pollfd %d", pollfd);
1733         }
1734 }
1735
1736 static
1737 int relay_add_connection(int fd, struct lttng_poll_event *events,
1738                 struct lttng_ht *relay_connections_ht)
1739 {
1740         struct relay_command *relay_connection;
1741         int ret;
1742
1743         relay_connection = zmalloc(sizeof(struct relay_command));
1744         if (relay_connection == NULL) {
1745                 PERROR("Relay command zmalloc");
1746                 goto error;
1747         }
1748         do {
1749                 ret = read(fd, relay_connection, sizeof(struct relay_command));
1750         } while (ret < 0 && errno == EINTR);
1751         if (ret < 0 || ret < sizeof(struct relay_command)) {
1752                 PERROR("read relay cmd pipe");
1753                 goto error_read;
1754         }
1755
1756         lttng_ht_node_init_ulong(&relay_connection->sock_n,
1757                         (unsigned long) relay_connection->sock->fd);
1758         rcu_read_lock();
1759         lttng_ht_add_unique_ulong(relay_connections_ht,
1760                         &relay_connection->sock_n);
1761         rcu_read_unlock();
1762         return lttng_poll_add(events,
1763                         relay_connection->sock->fd,
1764                         LPOLLIN | LPOLLRDHUP);
1765
1766 error_read:
1767         free(relay_connection);
1768 error:
1769         return -1;
1770 }
1771
1772 static
1773 void deferred_free_connection(struct rcu_head *head)
1774 {
1775         struct relay_command *relay_connection =
1776                 caa_container_of(head, struct relay_command, rcu_node);
1777
1778         lttcomm_destroy_sock(relay_connection->sock);
1779         free(relay_connection);
1780 }
1781
1782 static
1783 void relay_del_connection(struct lttng_ht *relay_connections_ht,
1784                 struct lttng_ht *streams_ht, struct lttng_ht_iter *iter,
1785                 struct relay_command *relay_connection)
1786 {
1787         int ret;
1788
1789         ret = lttng_ht_del(relay_connections_ht, iter);
1790         assert(!ret);
1791         if (relay_connection->type == RELAY_CONTROL) {
1792                 relay_delete_session(relay_connection, streams_ht);
1793         }
1794
1795         call_rcu(&relay_connection->rcu_node,
1796                 deferred_free_connection);
1797 }
1798
1799 /*
1800  * This thread does the actual work
1801  */
1802 static
1803 void *relay_thread_worker(void *data)
1804 {
1805         int ret, err = -1, last_seen_data_fd = -1;
1806         uint32_t nb_fd;
1807         struct relay_command *relay_connection;
1808         struct lttng_poll_event events;
1809         struct lttng_ht *relay_connections_ht;
1810         struct lttng_ht_node_ulong *node;
1811         struct lttng_ht_iter iter;
1812         struct lttng_ht *streams_ht;
1813         struct lttcomm_relayd_hdr recv_hdr;
1814
1815         DBG("[thread] Relay worker started");
1816
1817         rcu_register_thread();
1818
1819         /* table of connections indexed on socket */
1820         relay_connections_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1821         if (!relay_connections_ht) {
1822                 goto relay_connections_ht_error;
1823         }
1824
1825         /* tables of streams indexed by stream ID */
1826         streams_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1827         if (!streams_ht) {
1828                 goto streams_ht_error;
1829         }
1830
1831         ret = create_thread_poll_set(&events, 2);
1832         if (ret < 0) {
1833                 goto error_poll_create;
1834         }
1835
1836         ret = lttng_poll_add(&events, relay_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1837         if (ret < 0) {
1838                 goto error;
1839         }
1840
1841 restart:
1842         while (1) {
1843                 int idx = -1, i, seen_control = 0, last_notdel_data_fd = -1;
1844
1845                 /* Infinite blocking call, waiting for transmission */
1846                 DBG3("Relayd worker thread polling...");
1847                 ret = lttng_poll_wait(&events, -1);
1848                 if (ret < 0) {
1849                         /*
1850                          * Restart interrupted system call.
1851                          */
1852                         if (errno == EINTR) {
1853                                 goto restart;
1854                         }
1855                         goto error;
1856                 }
1857
1858                 nb_fd = ret;
1859
1860                 /*
1861                  * Process control. The control connection is prioritised so we don't
1862                  * starve it with high throughout put tracing data on the data
1863                  * connection.
1864                  */
1865                 for (i = 0; i < nb_fd; i++) {
1866                         /* Fetch once the poll data */
1867                         uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1868                         int pollfd = LTTNG_POLL_GETFD(&events, i);
1869
1870                         /* Thread quit pipe has been closed. Killing thread. */
1871                         ret = check_thread_quit_pipe(pollfd, revents);
1872                         if (ret) {
1873                                 err = 0;
1874                                 goto exit;
1875                         }
1876
1877                         /* Inspect the relay cmd pipe for new connection */
1878                         if (pollfd == relay_cmd_pipe[0]) {
1879                                 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1880                                         ERR("Relay pipe error");
1881                                         goto error;
1882                                 } else if (revents & LPOLLIN) {
1883                                         DBG("Relay command received");
1884                                         ret = relay_add_connection(relay_cmd_pipe[0],
1885                                                         &events, relay_connections_ht);
1886                                         if (ret < 0) {
1887                                                 goto error;
1888                                         }
1889                                 }
1890                         } else if (revents) {
1891                                 rcu_read_lock();
1892                                 lttng_ht_lookup(relay_connections_ht,
1893                                                 (void *)((unsigned long) pollfd),
1894                                                 &iter);
1895                                 node = lttng_ht_iter_get_node_ulong(&iter);
1896                                 if (node == NULL) {
1897                                         DBG2("Relay sock %d not found", pollfd);
1898                                         rcu_read_unlock();
1899                                         goto error;
1900                                 }
1901                                 relay_connection = caa_container_of(node,
1902                                                 struct relay_command, sock_n);
1903
1904                                 if (revents & (LPOLLERR)) {
1905                                         ERR("POLL ERROR");
1906                                         relay_cleanup_poll_connection(&events, pollfd);
1907                                         relay_del_connection(relay_connections_ht,
1908                                                         streams_ht, &iter,
1909                                                         relay_connection);
1910                                         if (last_seen_data_fd == pollfd) {
1911                                                 last_seen_data_fd = last_notdel_data_fd;
1912                                         }
1913                                 } else if (revents & (LPOLLHUP | LPOLLRDHUP)) {
1914                                         DBG("Socket %d hung up", pollfd);
1915                                         relay_cleanup_poll_connection(&events, pollfd);
1916                                         relay_del_connection(relay_connections_ht,
1917                                                         streams_ht, &iter,
1918                                                         relay_connection);
1919                                         if (last_seen_data_fd == pollfd) {
1920                                                 last_seen_data_fd = last_notdel_data_fd;
1921                                         }
1922                                 } else if (revents & LPOLLIN) {
1923                                         /* control socket */
1924                                         if (relay_connection->type == RELAY_CONTROL) {
1925                                                 ret = relay_connection->sock->ops->recvmsg(
1926                                                                 relay_connection->sock, &recv_hdr,
1927                                                                 sizeof(struct lttcomm_relayd_hdr), 0);
1928                                                 /* connection closed */
1929                                                 if (ret <= 0) {
1930                                                         relay_cleanup_poll_connection(&events, pollfd);
1931                                                         relay_del_connection(relay_connections_ht,
1932                                                                         streams_ht, &iter,
1933                                                                         relay_connection);
1934                                                         DBG("Control connection closed with %d", pollfd);
1935                                                 } else {
1936                                                         if (relay_connection->session) {
1937                                                                 DBG2("Relay worker receiving data for session : %" PRIu64,
1938                                                                                 relay_connection->session->id);
1939                                                         }
1940                                                         ret = relay_process_control(&recv_hdr,
1941                                                                         relay_connection,
1942                                                                         streams_ht);
1943                                                         if (ret < 0) {
1944                                                                 /* Clear the session on error. */
1945                                                                 relay_cleanup_poll_connection(&events, pollfd);
1946                                                                 relay_del_connection(relay_connections_ht,
1947                                                                                 streams_ht, &iter,
1948                                                                                 relay_connection);
1949                                                                 DBG("Connection closed with %d", pollfd);
1950                                                         }
1951                                                         seen_control = 1;
1952                                                 }
1953                                         } else {
1954                                                 /*
1955                                                  * Flag the last seen data fd not deleted. It will be
1956                                                  * used as the last seen fd if any fd gets deleted in
1957                                                  * this first loop.
1958                                                  */
1959                                                 last_notdel_data_fd = pollfd;
1960                                         }
1961                                 }
1962                                 rcu_read_unlock();
1963                         }
1964                 }
1965
1966                 /*
1967                  * The last loop handled a control request, go back to poll to make
1968                  * sure we prioritise the control socket.
1969                  */
1970                 if (seen_control) {
1971                         continue;
1972                 }
1973
1974                 if (last_seen_data_fd >= 0) {
1975                         for (i = 0; i < nb_fd; i++) {
1976                                 int pollfd = LTTNG_POLL_GETFD(&events, i);
1977                                 if (last_seen_data_fd == pollfd) {
1978                                         idx = i;
1979                                         break;
1980                                 }
1981                         }
1982                 }
1983
1984                 /* Process data connection. */
1985                 for (i = idx + 1; i < nb_fd; i++) {
1986                         /* Fetch the poll data. */
1987                         uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1988                         int pollfd = LTTNG_POLL_GETFD(&events, i);
1989
1990                         /* Skip the command pipe. It's handled in the first loop. */
1991                         if (pollfd == relay_cmd_pipe[0]) {
1992                                 continue;
1993                         }
1994
1995                         if (revents) {
1996                                 rcu_read_lock();
1997                                 lttng_ht_lookup(relay_connections_ht,
1998                                                 (void *)((unsigned long) pollfd),
1999                                                 &iter);
2000                                 node = lttng_ht_iter_get_node_ulong(&iter);
2001                                 if (node == NULL) {
2002                                         /* Skip it. Might be removed before. */
2003                                         rcu_read_unlock();
2004                                         continue;
2005                                 }
2006                                 relay_connection = caa_container_of(node,
2007                                                 struct relay_command, sock_n);
2008
2009                                 if (revents & LPOLLIN) {
2010                                         if (relay_connection->type != RELAY_DATA) {
2011                                                 continue;
2012                                         }
2013
2014                                         ret = relay_process_data(relay_connection, streams_ht);
2015                                         /* connection closed */
2016                                         if (ret < 0) {
2017                                                 relay_cleanup_poll_connection(&events, pollfd);
2018                                                 relay_del_connection(relay_connections_ht,
2019                                                                 streams_ht, &iter,
2020                                                                 relay_connection);
2021                                                 DBG("Data connection closed with %d", pollfd);
2022                                                 /*
2023                                                  * Every goto restart call sets the last seen fd where
2024                                                  * here we don't really care since we gracefully
2025                                                  * continue the loop after the connection is deleted.
2026                                                  */
2027                                         } else {
2028                                                 /* Keep last seen port. */
2029                                                 last_seen_data_fd = pollfd;
2030                                                 rcu_read_unlock();
2031                                                 goto restart;
2032                                         }
2033                                 }
2034                                 rcu_read_unlock();
2035                         }
2036                 }
2037                 last_seen_data_fd = -1;
2038         }
2039
2040 exit:
2041 error:
2042         lttng_poll_clean(&events);
2043
2044         /* empty the hash table and free the memory */
2045         rcu_read_lock();
2046         cds_lfht_for_each_entry(relay_connections_ht->ht, &iter.iter, node, node) {
2047                 node = lttng_ht_iter_get_node_ulong(&iter);
2048                 if (node) {
2049                         relay_connection = caa_container_of(node,
2050                                         struct relay_command, sock_n);
2051                         relay_del_connection(relay_connections_ht,
2052                                         streams_ht, &iter,
2053                                         relay_connection);
2054                 }
2055         }
2056         rcu_read_unlock();
2057 error_poll_create:
2058         lttng_ht_destroy(streams_ht);
2059 streams_ht_error:
2060         lttng_ht_destroy(relay_connections_ht);
2061 relay_connections_ht_error:
2062         /* Close relay cmd pipes */
2063         utils_close_pipe(relay_cmd_pipe);
2064         if (err) {
2065                 DBG("Thread exited with error");
2066         }
2067         DBG("Worker thread cleanup complete");
2068         free(data_buffer);
2069         stop_threads();
2070         rcu_unregister_thread();
2071         return NULL;
2072 }
2073
2074 /*
2075  * Create the relay command pipe to wake thread_manage_apps.
2076  * Closed in cleanup().
2077  */
2078 static int create_relay_cmd_pipe(void)
2079 {
2080         int ret;
2081
2082         ret = utils_create_pipe_cloexec(relay_cmd_pipe);
2083
2084         return ret;
2085 }
2086
2087 /*
2088  * main
2089  */
2090 int main(int argc, char **argv)
2091 {
2092         int ret = 0;
2093         void *status;
2094
2095         /* Create thread quit pipe */
2096         if ((ret = init_thread_quit_pipe()) < 0) {
2097                 goto error;
2098         }
2099
2100         /* Parse arguments */
2101         progname = argv[0];
2102         if ((ret = parse_args(argc, argv)) < 0) {
2103                 goto exit;
2104         }
2105
2106         if ((ret = set_signal_handler()) < 0) {
2107                 goto exit;
2108         }
2109
2110         /* Daemonize */
2111         if (opt_daemon) {
2112                 ret = daemon(0, 0);
2113                 if (ret < 0) {
2114                         PERROR("daemon");
2115                         goto exit;
2116                 }
2117         }
2118
2119         /* Check if daemon is UID = 0 */
2120         is_root = !getuid();
2121
2122         if (!is_root) {
2123                 if (control_uri->port < 1024 || data_uri->port < 1024) {
2124                         ERR("Need to be root to use ports < 1024");
2125                         ret = -1;
2126                         goto exit;
2127                 }
2128         }
2129
2130         /* Setup the thread apps communication pipe. */
2131         if ((ret = create_relay_cmd_pipe()) < 0) {
2132                 goto exit;
2133         }
2134
2135         /* Init relay command queue. */
2136         cds_wfq_init(&relay_cmd_queue.queue);
2137
2138         /* Set up max poll set size */
2139         lttng_poll_set_max_size();
2140
2141         /* Setup the dispatcher thread */
2142         ret = pthread_create(&dispatcher_thread, NULL,
2143                         relay_thread_dispatcher, (void *) NULL);
2144         if (ret != 0) {
2145                 PERROR("pthread_create dispatcher");
2146                 goto exit_dispatcher;
2147         }
2148
2149         /* Setup the worker thread */
2150         ret = pthread_create(&worker_thread, NULL,
2151                         relay_thread_worker, (void *) NULL);
2152         if (ret != 0) {
2153                 PERROR("pthread_create worker");
2154                 goto exit_worker;
2155         }
2156
2157         /* Setup the listener thread */
2158         ret = pthread_create(&listener_thread, NULL,
2159                         relay_thread_listener, (void *) NULL);
2160         if (ret != 0) {
2161                 PERROR("pthread_create listener");
2162                 goto exit_listener;
2163         }
2164
2165 exit_listener:
2166         ret = pthread_join(listener_thread, &status);
2167         if (ret != 0) {
2168                 PERROR("pthread_join");
2169                 goto error;     /* join error, exit without cleanup */
2170         }
2171
2172 exit_worker:
2173         ret = pthread_join(worker_thread, &status);
2174         if (ret != 0) {
2175                 PERROR("pthread_join");
2176                 goto error;     /* join error, exit without cleanup */
2177         }
2178
2179 exit_dispatcher:
2180         ret = pthread_join(dispatcher_thread, &status);
2181         if (ret != 0) {
2182                 PERROR("pthread_join");
2183                 goto error;     /* join error, exit without cleanup */
2184         }
2185
2186 exit:
2187         cleanup();
2188         if (!ret) {
2189                 exit(EXIT_SUCCESS);
2190         }
2191
2192 error:
2193         exit(EXIT_FAILURE);
2194 }