src/bin/lttng-sessiond/consumer.c

   1 /*
   2  * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _LGPL_SOURCE
  19 #include <assert.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <sys/stat.h>
  24 #include <sys/types.h>
  25 #include <unistd.h>
  26 #include <inttypes.h>
  27
  28 #include <common/common.h>
  29 #include <common/defaults.h>
  30 #include <common/uri.h>
  31 #include <common/relayd/relayd.h>
  32
  33 #include "consumer.h"
  34 #include "health-sessiond.h"
  35 #include "ust-app.h"
  36 #include "utils.h"
  37
  38 /*
  39  * Send a data payload using a given consumer socket of size len.
  40  *
  41  * The consumer socket lock MUST be acquired before calling this since this
  42  * function can change the fd value.
  43  *
  44  * Return 0 on success else a negative value on error.
  45  */
  46 int consumer_socket_send(struct consumer_socket *socket, void *msg, size_t len)
  47 {
  48         int fd;
  49         ssize_t size;
  50
  51         assert(socket);
  52         assert(socket->fd_ptr);
  53         assert(msg);
  54
  55         /* Consumer socket is invalid. Stopping. */
  56         fd = *socket->fd_ptr;
  57         if (fd < 0) {
  58                 goto error;
  59         }
  60
  61         size = lttcomm_send_unix_sock(fd, msg, len);
  62         if (size < 0) {
  63                 /* The above call will print a PERROR on error. */
  64                 DBG("Error when sending data to consumer on sock %d", fd);
  65                 /*
  66                  * At this point, the socket is not usable anymore thus closing it and
  67                  * setting the file descriptor to -1 so it is not reused.
  68                  */
  69
  70                 /* This call will PERROR on error. */
  71                 (void) lttcomm_close_unix_sock(fd);
  72                 *socket->fd_ptr = -1;
  73                 goto error;
  74         }
  75
  76         return 0;
  77
  78 error:
  79         return -1;
  80 }
  81
  82 /*
  83  * Receive a data payload using a given consumer socket of size len.
  84  *
  85  * The consumer socket lock MUST be acquired before calling this since this
  86  * function can change the fd value.
  87  *
  88  * Return 0 on success else a negative value on error.
  89  */
  90 int consumer_socket_recv(struct consumer_socket *socket, void *msg, size_t len)
  91 {
  92         int fd;
  93         ssize_t size;
  94
  95         assert(socket);
  96         assert(socket->fd_ptr);
  97         assert(msg);
  98
  99         /* Consumer socket is invalid. Stopping. */
 100         fd = *socket->fd_ptr;
 101         if (fd < 0) {
 102                 goto error;
 103         }
 104
 105         size = lttcomm_recv_unix_sock(fd, msg, len);
 106         if (size <= 0) {
 107                 /* The above call will print a PERROR on error. */
 108                 DBG("Error when receiving data from the consumer socket %d", fd);
 109                 /*
 110                  * At this point, the socket is not usable anymore thus closing it and
 111                  * setting the file descriptor to -1 so it is not reused.
 112                  */
 113
 114                 /* This call will PERROR on error. */
 115                 (void) lttcomm_close_unix_sock(fd);
 116                 *socket->fd_ptr = -1;
 117                 goto error;
 118         }
 119
 120         return 0;
 121
 122 error:
 123         return -1;
 124 }
 125
 126 /*
 127  * Receive a reply command status message from the consumer. Consumer socket
 128  * lock MUST be acquired before calling this function.
 129  *
 130  * Return 0 on success, -1 on recv error or a negative lttng error code which
 131  * was possibly returned by the consumer.
 132  */
 133 int consumer_recv_status_reply(struct consumer_socket *sock)
 134 {
 135         int ret;
 136         struct lttcomm_consumer_status_msg reply;
 137
 138         assert(sock);
 139
 140         ret = consumer_socket_recv(sock, &reply, sizeof(reply));
 141         if (ret < 0) {
 142                 goto end;
 143         }
 144
 145         if (reply.ret_code == LTTCOMM_CONSUMERD_SUCCESS) {
 146                 /* All good. */
 147                 ret = 0;
 148         } else {
 149                 ret = -reply.ret_code;
 150                 DBG("Consumer ret code %d", ret);
 151         }
 152
 153 end:
 154         return ret;
 155 }
 156
 157 /*
 158  * Once the ASK_CHANNEL command is sent to the consumer, the channel
 159  * information are sent back. This call receives that data and populates key
 160  * and stream_count.
 161  *
 162  * On success return 0 and both key and stream_count are set. On error, a
 163  * negative value is sent back and both parameters are untouched.
 164  */
 165 int consumer_recv_status_channel(struct consumer_socket *sock,
 166                 uint64_t *key, unsigned int *stream_count)
 167 {
 168         int ret;
 169         struct lttcomm_consumer_status_channel reply;
 170
 171         assert(sock);
 172         assert(stream_count);
 173         assert(key);
 174
 175         ret = consumer_socket_recv(sock, &reply, sizeof(reply));
 176         if (ret < 0) {
 177                 goto end;
 178         }
 179
 180         /* An error is possible so don't touch the key and stream_count. */
 181         if (reply.ret_code != LTTCOMM_CONSUMERD_SUCCESS) {
 182                 ret = -1;
 183                 goto end;
 184         }
 185
 186         *key = reply.key;
 187         *stream_count = reply.stream_count;
 188         ret = 0;
 189
 190 end:
 191         return ret;
 192 }
 193
 194 /*
 195  * Send destroy relayd command to consumer.
 196  *
 197  * On success return positive value. On error, negative value.
 198  */
 199 int consumer_send_destroy_relayd(struct consumer_socket *sock,
 200                 struct consumer_output *consumer)
 201 {
 202         int ret;
 203         struct lttcomm_consumer_msg msg;
 204
 205         assert(consumer);
 206         assert(sock);
 207
 208         DBG2("Sending destroy relayd command to consumer sock %d", *sock->fd_ptr);
 209
 210         memset(&msg, 0, sizeof(msg));
 211         msg.cmd_type = LTTNG_CONSUMER_DESTROY_RELAYD;
 212         msg.u.destroy_relayd.net_seq_idx = consumer->net_seq_index;
 213
 214         pthread_mutex_lock(sock->lock);
 215         ret = consumer_socket_send(sock, &msg, sizeof(msg));
 216         if (ret < 0) {
 217                 goto error;
 218         }
 219
 220         /* Don't check the return value. The caller will do it. */
 221         ret = consumer_recv_status_reply(sock);
 222
 223         DBG2("Consumer send destroy relayd command done");
 224
 225 error:
 226         pthread_mutex_unlock(sock->lock);
 227         return ret;
 228 }
 229
 230 /*
 231  * For each consumer socket in the consumer output object, send a destroy
 232  * relayd command.
 233  */
 234 void consumer_output_send_destroy_relayd(struct consumer_output *consumer)
 235 {
 236         struct lttng_ht_iter iter;
 237         struct consumer_socket *socket;
 238
 239         assert(consumer);
 240
 241         /* Destroy any relayd connection */
 242         if (consumer->type == CONSUMER_DST_NET) {
 243                 rcu_read_lock();
 244                 cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
 245                                 node.node) {
 246                         int ret;
 247
 248                         /* Send destroy relayd command */
 249                         ret = consumer_send_destroy_relayd(socket, consumer);
 250                         if (ret < 0) {
 251                                 DBG("Unable to send destroy relayd command to consumer");
 252                                 /* Continue since we MUST delete everything at this point. */
 253                         }
 254                 }
 255                 rcu_read_unlock();
 256         }
 257 }
 258
 259 /*
 260  * From a consumer_data structure, allocate and add a consumer socket to the
 261  * consumer output.
 262  *
 263  * Return 0 on success, else negative value on error
 264  */
 265 int consumer_create_socket(struct consumer_data *data,
 266                 struct consumer_output *output)
 267 {
 268         int ret = 0;
 269         struct consumer_socket *socket;
 270
 271         assert(data);
 272
 273         if (output == NULL || data->cmd_sock < 0) {
 274                 /*
 275                  * Not an error. Possible there is simply not spawned consumer or it's
 276                  * disabled for the tracing session asking the socket.
 277                  */
 278                 goto error;
 279         }
 280
 281         rcu_read_lock();
 282         socket = consumer_find_socket(data->cmd_sock, output);
 283         rcu_read_unlock();
 284         if (socket == NULL) {
 285                 socket = consumer_allocate_socket(&data->cmd_sock);
 286                 if (socket == NULL) {
 287                         ret = -1;
 288                         goto error;
 289                 }
 290
 291                 socket->registered = 0;
 292                 socket->lock = &data->lock;
 293                 rcu_read_lock();
 294                 consumer_add_socket(socket, output);
 295                 rcu_read_unlock();
 296         }
 297
 298         socket->type = data->type;
 299
 300         DBG3("Consumer socket created (fd: %d) and added to output",
 301                         data->cmd_sock);
 302
 303 error:
 304         return ret;
 305 }
 306
 307 /*
 308  * Return the consumer socket from the given consumer output with the right
 309  * bitness. On error, returns NULL.
 310  *
 311  * The caller MUST acquire a rcu read side lock and keep it until the socket
 312  * object reference is not needed anymore.
 313  */
 314 struct consumer_socket *consumer_find_socket_by_bitness(int bits,
 315                 struct consumer_output *consumer)
 316 {
 317         int consumer_fd;
 318         struct consumer_socket *socket = NULL;
 319
 320         switch (bits) {
 321         case 64:
 322                 consumer_fd = uatomic_read(&ust_consumerd64_fd);
 323                 break;
 324         case 32:
 325                 consumer_fd = uatomic_read(&ust_consumerd32_fd);
 326                 break;
 327         default:
 328                 assert(0);
 329                 goto end;
 330         }
 331
 332         socket = consumer_find_socket(consumer_fd, consumer);
 333         if (!socket) {
 334                 ERR("Consumer socket fd %d not found in consumer obj %p",
 335                                 consumer_fd, consumer);
 336         }
 337
 338 end:
 339         return socket;
 340 }
 341
 342 /*
 343  * Find a consumer_socket in a consumer_output hashtable. Read side lock must
 344  * be acquired before calling this function and across use of the
 345  * returned consumer_socket.
 346  */
 347 struct consumer_socket *consumer_find_socket(int key,
 348                 struct consumer_output *consumer)
 349 {
 350         struct lttng_ht_iter iter;
 351         struct lttng_ht_node_ulong *node;
 352         struct consumer_socket *socket = NULL;
 353
 354         /* Negative keys are lookup failures */
 355         if (key < 0 || consumer == NULL) {
 356                 return NULL;
 357         }
 358
 359         lttng_ht_lookup(consumer->socks, (void *)((unsigned long) key),
 360                         &iter);
 361         node = lttng_ht_iter_get_node_ulong(&iter);
 362         if (node != NULL) {
 363                 socket = caa_container_of(node, struct consumer_socket, node);
 364         }
 365
 366         return socket;
 367 }
 368
 369 /*
 370  * Allocate a new consumer_socket and return the pointer.
 371  */
 372 struct consumer_socket *consumer_allocate_socket(int *fd)
 373 {
 374         struct consumer_socket *socket = NULL;
 375
 376         assert(fd);
 377
 378         socket = zmalloc(sizeof(struct consumer_socket));
 379         if (socket == NULL) {
 380                 PERROR("zmalloc consumer socket");
 381                 goto error;
 382         }
 383
 384         socket->fd_ptr = fd;
 385         lttng_ht_node_init_ulong(&socket->node, *fd);
 386
 387 error:
 388         return socket;
 389 }
 390
 391 /*
 392  * Add consumer socket to consumer output object. Read side lock must be
 393  * acquired before calling this function.
 394  */
 395 void consumer_add_socket(struct consumer_socket *sock,
 396                 struct consumer_output *consumer)
 397 {
 398         assert(sock);
 399         assert(consumer);
 400
 401         lttng_ht_add_unique_ulong(consumer->socks, &sock->node);
 402 }
 403
 404 /*
 405  * Delte consumer socket to consumer output object. Read side lock must be
 406  * acquired before calling this function.
 407  */
 408 void consumer_del_socket(struct consumer_socket *sock,
 409                 struct consumer_output *consumer)
 410 {
 411         int ret;
 412         struct lttng_ht_iter iter;
 413
 414         assert(sock);
 415         assert(consumer);
 416
 417         iter.iter.node = &sock->node.node;
 418         ret = lttng_ht_del(consumer->socks, &iter);
 419         assert(!ret);
 420 }
 421
 422 /*
 423  * RCU destroy call function.
 424  */
 425 static void destroy_socket_rcu(struct rcu_head *head)
 426 {
 427         struct lttng_ht_node_ulong *node =
 428                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 429         struct consumer_socket *socket =
 430                 caa_container_of(node, struct consumer_socket, node);
 431
 432         free(socket);
 433 }
 434
 435 /*
 436  * Destroy and free socket pointer in a call RCU. Read side lock must be
 437  * acquired before calling this function.
 438  */
 439 void consumer_destroy_socket(struct consumer_socket *sock)
 440 {
 441         assert(sock);
 442
 443         /*
 444          * We DO NOT close the file descriptor here since it is global to the
 445          * session daemon and is closed only if the consumer dies or a custom
 446          * consumer was registered,
 447          */
 448         if (sock->registered) {
 449                 DBG3("Consumer socket was registered. Closing fd %d", *sock->fd_ptr);
 450                 lttcomm_close_unix_sock(*sock->fd_ptr);
 451         }
 452
 453         call_rcu(&sock->node.head, destroy_socket_rcu);
 454 }
 455
 456 /*
 457  * Allocate and assign data to a consumer_output object.
 458  *
 459  * Return pointer to structure.
 460  */
 461 struct consumer_output *consumer_create_output(enum consumer_dst_type type)
 462 {
 463         struct consumer_output *output = NULL;
 464
 465         output = zmalloc(sizeof(struct consumer_output));
 466         if (output == NULL) {
 467                 PERROR("zmalloc consumer_output");
 468                 goto error;
 469         }
 470
 471         /* By default, consumer output is enabled */
 472         output->enabled = 1;
 473         output->type = type;
 474         output->net_seq_index = (uint64_t) -1ULL;
 475         urcu_ref_init(&output->ref);
 476
 477         output->socks = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 478
 479 error:
 480         return output;
 481 }
 482
 483 /*
 484  * Iterate over the consumer output socket hash table and destroy them. The
 485  * socket file descriptor are only closed if the consumer output was
 486  * registered meaning it's an external consumer.
 487  */
 488 void consumer_destroy_output_sockets(struct consumer_output *obj)
 489 {
 490         struct lttng_ht_iter iter;
 491         struct consumer_socket *socket;
 492
 493         if (!obj->socks) {
 494                 return;
 495         }
 496
 497         rcu_read_lock();
 498         cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 499                 consumer_del_socket(socket, obj);
 500                 consumer_destroy_socket(socket);
 501         }
 502         rcu_read_unlock();
 503 }
 504
 505 /*
 506  * Delete the consumer_output object from the list and free the ptr.
 507  *
 508  * Should *NOT* be called with RCU read-side lock held.
 509  */
 510 static void consumer_release_output(struct urcu_ref *ref)
 511 {
 512         struct consumer_output *obj =
 513                 caa_container_of(ref, struct consumer_output, ref);
 514
 515         consumer_destroy_output_sockets(obj);
 516
 517         if (obj->socks) {
 518                 /* Finally destroy HT */
 519                 ht_cleanup_push(obj->socks);
 520         }
 521
 522         free(obj);
 523 }
 524
 525 /*
 526  * Get the consumer_output object.
 527  */
 528 void consumer_output_get(struct consumer_output *obj)
 529 {
 530         urcu_ref_get(&obj->ref);
 531 }
 532
 533 /*
 534  * Put the consumer_output object.
 535  *
 536  * Should *NOT* be called with RCU read-side lock held.
 537  */
 538 void consumer_output_put(struct consumer_output *obj)
 539 {
 540         if (!obj) {
 541                 return;
 542         }
 543         urcu_ref_put(&obj->ref, consumer_release_output);
 544 }
 545
 546 /*
 547  * Copy consumer output and returned the newly allocated copy.
 548  *
 549  * Should *NOT* be called with RCU read-side lock held.
 550  */
 551 struct consumer_output *consumer_copy_output(struct consumer_output *obj)
 552 {
 553         int ret;
 554         struct consumer_output *output;
 555
 556         assert(obj);
 557
 558         output = consumer_create_output(obj->type);
 559         if (output == NULL) {
 560                 goto end;
 561         }
 562         output->enabled = obj->enabled;
 563         output->net_seq_index = obj->net_seq_index;
 564         memcpy(output->subdir, obj->subdir, PATH_MAX);
 565         output->snapshot = obj->snapshot;
 566         output->relay_major_version = obj->relay_major_version;
 567         output->relay_minor_version = obj->relay_minor_version;
 568         memcpy(&output->dst, &obj->dst, sizeof(output->dst));
 569         ret = consumer_copy_sockets(output, obj);
 570         if (ret < 0) {
 571                 goto error_put;
 572         }
 573 end:
 574         return output;
 575
 576 error_put:
 577         consumer_output_put(output);
 578         return NULL;
 579 }
 580
 581 /*
 582  * Copy consumer sockets from src to dst.
 583  *
 584  * Return 0 on success or else a negative value.
 585  */
 586 int consumer_copy_sockets(struct consumer_output *dst,
 587                 struct consumer_output *src)
 588 {
 589         int ret = 0;
 590         struct lttng_ht_iter iter;
 591         struct consumer_socket *socket, *copy_sock;
 592
 593         assert(dst);
 594         assert(src);
 595
 596         rcu_read_lock();
 597         cds_lfht_for_each_entry(src->socks->ht, &iter.iter, socket, node.node) {
 598                 /* Ignore socket that are already there. */
 599                 copy_sock = consumer_find_socket(*socket->fd_ptr, dst);
 600                 if (copy_sock) {
 601                         continue;
 602                 }
 603
 604                 /* Create new socket object. */
 605                 copy_sock = consumer_allocate_socket(socket->fd_ptr);
 606                 if (copy_sock == NULL) {
 607                         rcu_read_unlock();
 608                         ret = -ENOMEM;
 609                         goto error;
 610                 }
 611
 612                 copy_sock->registered = socket->registered;
 613                 /*
 614                  * This is valid because this lock is shared accross all consumer
 615                  * object being the global lock of the consumer data structure of the
 616                  * session daemon.
 617                  */
 618                 copy_sock->lock = socket->lock;
 619                 consumer_add_socket(copy_sock, dst);
 620         }
 621         rcu_read_unlock();
 622
 623 error:
 624         return ret;
 625 }
 626
 627 /*
 628  * Set network URI to the consumer output object.
 629  *
 630  * Return 0 on success. Return 1 if the URI were equal. Else, negative value on
 631  * error.
 632  */
 633 int consumer_set_network_uri(struct consumer_output *obj,
 634                 struct lttng_uri *uri)
 635 {
 636         int ret;
 637         char tmp_path[PATH_MAX];
 638         char hostname[HOST_NAME_MAX];
 639         struct lttng_uri *dst_uri = NULL;
 640
 641         /* Code flow error safety net. */
 642         assert(obj);
 643         assert(uri);
 644
 645         switch (uri->stype) {
 646         case LTTNG_STREAM_CONTROL:
 647                 dst_uri = &obj->dst.net.control;
 648                 obj->dst.net.control_isset = 1;
 649                 if (uri->port == 0) {
 650                         /* Assign default port. */
 651                         uri->port = DEFAULT_NETWORK_CONTROL_PORT;
 652                 } else {
 653                         if (obj->dst.net.data_isset && uri->port ==
 654                                         obj->dst.net.data.port) {
 655                                 ret = -LTTNG_ERR_INVALID;
 656                                 goto error;
 657                         }
 658                 }
 659                 DBG3("Consumer control URI set with port %d", uri->port);
 660                 break;
 661         case LTTNG_STREAM_DATA:
 662                 dst_uri = &obj->dst.net.data;
 663                 obj->dst.net.data_isset = 1;
 664                 if (uri->port == 0) {
 665                         /* Assign default port. */
 666                         uri->port = DEFAULT_NETWORK_DATA_PORT;
 667                 } else {
 668                         if (obj->dst.net.control_isset && uri->port ==
 669                                         obj->dst.net.control.port) {
 670                                 ret = -LTTNG_ERR_INVALID;
 671                                 goto error;
 672                         }
 673                 }
 674                 DBG3("Consumer data URI set with port %d", uri->port);
 675                 break;
 676         default:
 677                 ERR("Set network uri type unknown %d", uri->stype);
 678                 ret = -LTTNG_ERR_INVALID;
 679                 goto error;
 680         }
 681
 682         ret = uri_compare(dst_uri, uri);
 683         if (!ret) {
 684                 /* Same URI, don't touch it and return success. */
 685                 DBG3("URI network compare are the same");
 686                 goto equal;
 687         }
 688
 689         /* URIs were not equal, replacing it. */
 690         memset(dst_uri, 0, sizeof(struct lttng_uri));
 691         memcpy(dst_uri, uri, sizeof(struct lttng_uri));
 692         obj->type = CONSUMER_DST_NET;
 693
 694         /* Handle subdir and add hostname in front. */
 695         if (dst_uri->stype == LTTNG_STREAM_CONTROL) {
 696                 /* Get hostname to append it in the pathname */
 697                 ret = gethostname(hostname, sizeof(hostname));
 698                 if (ret < 0) {
 699                         PERROR("gethostname. Fallback on default localhost");
 700                         strncpy(hostname, "localhost", sizeof(hostname));
 701                 }
 702                 hostname[sizeof(hostname) - 1] = '\0';
 703
 704                 /* Setup consumer subdir if none present in the control URI */
 705                 if (strlen(dst_uri->subdir) == 0) {
 706                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 707                                         hostname, obj->subdir);
 708                 } else {
 709                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 710                                         hostname, dst_uri->subdir);
 711                 }
 712                 if (ret < 0) {
 713                         PERROR("snprintf set consumer uri subdir");
 714                         ret = -LTTNG_ERR_NOMEM;
 715                         goto error;
 716                 }
 717
 718                 if (lttng_strncpy(obj->subdir, tmp_path, sizeof(obj->subdir))) {
 719                         ret = -LTTNG_ERR_INVALID;
 720                         goto error;
 721                 }
 722                 DBG3("Consumer set network uri subdir path %s", tmp_path);
 723         }
 724
 725         return 0;
 726 equal:
 727         return 1;
 728 error:
 729         return ret;
 730 }
 731
 732 /*
 733  * Send file descriptor to consumer via sock.
 734  *
 735  * The consumer socket lock must be held by the caller.
 736  */
 737 int consumer_send_fds(struct consumer_socket *sock, int *fds, size_t nb_fd)
 738 {
 739         int ret;
 740
 741         assert(fds);
 742         assert(sock);
 743         assert(nb_fd > 0);
 744         assert(pthread_mutex_trylock(sock->lock) == EBUSY);
 745
 746         ret = lttcomm_send_fds_unix_sock(*sock->fd_ptr, fds, nb_fd);
 747         if (ret < 0) {
 748                 /* The above call will print a PERROR on error. */
 749                 DBG("Error when sending consumer fds on sock %d", *sock->fd_ptr);
 750                 goto error;
 751         }
 752
 753         ret = consumer_recv_status_reply(sock);
 754 error:
 755         return ret;
 756 }
 757
 758 /*
 759  * Consumer send communication message structure to consumer.
 760  *
 761  * The consumer socket lock must be held by the caller.
 762  */
 763 int consumer_send_msg(struct consumer_socket *sock,
 764                 struct lttcomm_consumer_msg *msg)
 765 {
 766         int ret;
 767
 768         assert(msg);
 769         assert(sock);
 770         assert(pthread_mutex_trylock(sock->lock) == EBUSY);
 771
 772         ret = consumer_socket_send(sock, msg, sizeof(struct lttcomm_consumer_msg));
 773         if (ret < 0) {
 774                 goto error;
 775         }
 776
 777         ret = consumer_recv_status_reply(sock);
 778
 779 error:
 780         return ret;
 781 }
 782
 783 /*
 784  * Consumer send channel communication message structure to consumer.
 785  *
 786  * The consumer socket lock must be held by the caller.
 787  */
 788 int consumer_send_channel(struct consumer_socket *sock,
 789                 struct lttcomm_consumer_msg *msg)
 790 {
 791         int ret;
 792
 793         assert(msg);
 794         assert(sock);
 795
 796         ret = consumer_send_msg(sock, msg);
 797         if (ret < 0) {
 798                 goto error;
 799         }
 800
 801 error:
 802         return ret;
 803 }
 804
 805 /*
 806  * Populate the given consumer msg structure with the ask_channel command
 807  * information.
 808  */
 809 void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 810                 uint64_t subbuf_size,
 811                 uint64_t num_subbuf,
 812                 int overwrite,
 813                 unsigned int switch_timer_interval,
 814                 unsigned int read_timer_interval,
 815                 unsigned int live_timer_interval,
 816                 unsigned int monitor_timer_interval,
 817                 int output,
 818                 int type,
 819                 uint64_t session_id,
 820                 const char *pathname,
 821                 const char *name,
 822                 uid_t uid,
 823                 gid_t gid,
 824                 uint64_t relayd_id,
 825                 uint64_t key,
 826                 unsigned char *uuid,
 827                 uint32_t chan_id,
 828                 uint64_t tracefile_size,
 829                 uint64_t tracefile_count,
 830                 uint64_t session_id_per_pid,
 831                 unsigned int monitor,
 832                 uint32_t ust_app_uid,
 833                 int64_t blocking_timeout,
 834                 const char *root_shm_path,
 835                 const char *shm_path)
 836 {
 837         assert(msg);
 838
 839         /* Zeroed structure */
 840         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 841
 842         msg->cmd_type = LTTNG_CONSUMER_ASK_CHANNEL_CREATION;
 843         msg->u.ask_channel.subbuf_size = subbuf_size;
 844         msg->u.ask_channel.num_subbuf = num_subbuf ;
 845         msg->u.ask_channel.overwrite = overwrite;
 846         msg->u.ask_channel.switch_timer_interval = switch_timer_interval;
 847         msg->u.ask_channel.read_timer_interval = read_timer_interval;
 848         msg->u.ask_channel.live_timer_interval = live_timer_interval;
 849         msg->u.ask_channel.monitor_timer_interval = monitor_timer_interval;
 850         msg->u.ask_channel.output = output;
 851         msg->u.ask_channel.type = type;
 852         msg->u.ask_channel.session_id = session_id;
 853         msg->u.ask_channel.session_id_per_pid = session_id_per_pid;
 854         msg->u.ask_channel.uid = uid;
 855         msg->u.ask_channel.gid = gid;
 856         msg->u.ask_channel.relayd_id = relayd_id;
 857         msg->u.ask_channel.key = key;
 858         msg->u.ask_channel.chan_id = chan_id;
 859         msg->u.ask_channel.tracefile_size = tracefile_size;
 860         msg->u.ask_channel.tracefile_count = tracefile_count;
 861         msg->u.ask_channel.monitor = monitor;
 862         msg->u.ask_channel.ust_app_uid = ust_app_uid;
 863         msg->u.ask_channel.blocking_timeout = blocking_timeout;
 864
 865         memcpy(msg->u.ask_channel.uuid, uuid, sizeof(msg->u.ask_channel.uuid));
 866
 867         if (pathname) {
 868                 strncpy(msg->u.ask_channel.pathname, pathname,
 869                                 sizeof(msg->u.ask_channel.pathname));
 870                 msg->u.ask_channel.pathname[sizeof(msg->u.ask_channel.pathname)-1] = '\0';
 871         }
 872
 873         strncpy(msg->u.ask_channel.name, name, sizeof(msg->u.ask_channel.name));
 874         msg->u.ask_channel.name[sizeof(msg->u.ask_channel.name) - 1] = '\0';
 875
 876         if (root_shm_path) {
 877                 strncpy(msg->u.ask_channel.root_shm_path, root_shm_path,
 878                         sizeof(msg->u.ask_channel.root_shm_path));
 879                 msg->u.ask_channel.root_shm_path[sizeof(msg->u.ask_channel.root_shm_path) - 1] = '\0';
 880         }
 881         if (shm_path) {
 882                 strncpy(msg->u.ask_channel.shm_path, shm_path,
 883                         sizeof(msg->u.ask_channel.shm_path));
 884                 msg->u.ask_channel.shm_path[sizeof(msg->u.ask_channel.shm_path) - 1] = '\0';
 885         }
 886 }
 887
 888 /*
 889  * Init channel communication message structure.
 890  */
 891 void consumer_init_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 892                 enum lttng_consumer_command cmd,
 893                 uint64_t channel_key,
 894                 uint64_t session_id,
 895                 const char *pathname,
 896                 uid_t uid,
 897                 gid_t gid,
 898                 uint64_t relayd_id,
 899                 const char *name,
 900                 unsigned int nb_init_streams,
 901                 enum lttng_event_output output,
 902                 int type,
 903                 uint64_t tracefile_size,
 904                 uint64_t tracefile_count,
 905                 unsigned int monitor,
 906                 unsigned int live_timer_interval,
 907                 unsigned int monitor_timer_interval)
 908 {
 909         assert(msg);
 910
 911         /* Zeroed structure */
 912         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 913
 914         /* Send channel */
 915         msg->cmd_type = cmd;
 916         msg->u.channel.channel_key = channel_key;
 917         msg->u.channel.session_id = session_id;
 918         msg->u.channel.uid = uid;
 919         msg->u.channel.gid = gid;
 920         msg->u.channel.relayd_id = relayd_id;
 921         msg->u.channel.nb_init_streams = nb_init_streams;
 922         msg->u.channel.output = output;
 923         msg->u.channel.type = type;
 924         msg->u.channel.tracefile_size = tracefile_size;
 925         msg->u.channel.tracefile_count = tracefile_count;
 926         msg->u.channel.monitor = monitor;
 927         msg->u.channel.live_timer_interval = live_timer_interval;
 928         msg->u.channel.monitor_timer_interval = monitor_timer_interval;
 929
 930         strncpy(msg->u.channel.pathname, pathname,
 931                         sizeof(msg->u.channel.pathname));
 932         msg->u.channel.pathname[sizeof(msg->u.channel.pathname) - 1] = '\0';
 933
 934         strncpy(msg->u.channel.name, name, sizeof(msg->u.channel.name));
 935         msg->u.channel.name[sizeof(msg->u.channel.name) - 1] = '\0';
 936 }
 937
 938 /*
 939  * Init stream communication message structure.
 940  */
 941 void consumer_init_stream_comm_msg(struct lttcomm_consumer_msg *msg,
 942                 enum lttng_consumer_command cmd,
 943                 uint64_t channel_key,
 944                 uint64_t stream_key,
 945                 int cpu)
 946 {
 947         assert(msg);
 948
 949         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 950
 951         msg->cmd_type = cmd;
 952         msg->u.stream.channel_key = channel_key;
 953         msg->u.stream.stream_key = stream_key;
 954         msg->u.stream.cpu = cpu;
 955 }
 956
 957 void consumer_init_streams_sent_comm_msg(struct lttcomm_consumer_msg *msg,
 958                 enum lttng_consumer_command cmd,
 959                 uint64_t channel_key, uint64_t net_seq_idx)
 960 {
 961         assert(msg);
 962
 963         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 964
 965         msg->cmd_type = cmd;
 966         msg->u.sent_streams.channel_key = channel_key;
 967         msg->u.sent_streams.net_seq_idx = net_seq_idx;
 968 }
 969
 970 /*
 971  * Send stream communication structure to the consumer.
 972  */
 973 int consumer_send_stream(struct consumer_socket *sock,
 974                 struct consumer_output *dst, struct lttcomm_consumer_msg *msg,
 975                 int *fds, size_t nb_fd)
 976 {
 977         int ret;
 978
 979         assert(msg);
 980         assert(dst);
 981         assert(sock);
 982         assert(fds);
 983
 984         ret = consumer_send_msg(sock, msg);
 985         if (ret < 0) {
 986                 goto error;
 987         }
 988
 989         ret = consumer_send_fds(sock, fds, nb_fd);
 990         if (ret < 0) {
 991                 goto error;
 992         }
 993
 994 error:
 995         return ret;
 996 }
 997
 998 /*
 999  * Send relayd socket to consumer associated with a session name.
1000  *
1001  * The consumer socket lock must be held by the caller.
1002  *
1003  * On success return positive value. On error, negative value.
1004  */
1005 int consumer_send_relayd_socket(struct consumer_socket *consumer_sock,
1006                 struct lttcomm_relayd_sock *rsock, struct consumer_output *consumer,
1007                 enum lttng_stream_type type, uint64_t session_id,
1008                 char *session_name, char *hostname, int session_live_timer)
1009 {
1010         int ret;
1011         struct lttcomm_consumer_msg msg;
1012
1013         /* Code flow error. Safety net. */
1014         assert(rsock);
1015         assert(consumer);
1016         assert(consumer_sock);
1017
1018         memset(&msg, 0, sizeof(msg));
1019         /* Bail out if consumer is disabled */
1020         if (!consumer->enabled) {
1021                 ret = LTTNG_OK;
1022                 goto error;
1023         }
1024
1025         if (type == LTTNG_STREAM_CONTROL) {
1026                 ret = relayd_create_session(rsock,
1027                                 &msg.u.relayd_sock.relayd_session_id,
1028                                 session_name, hostname, session_live_timer,
1029                                 consumer->snapshot);
1030                 if (ret < 0) {
1031                         /* Close the control socket. */
1032                         (void) relayd_close(rsock);
1033                         goto error;
1034                 }
1035         }
1036
1037         msg.cmd_type = LTTNG_CONSUMER_ADD_RELAYD_SOCKET;
1038         /*
1039          * Assign network consumer output index using the temporary consumer since
1040          * this call should only be made from within a set_consumer_uri() function
1041          * call in the session daemon.
1042          */
1043         msg.u.relayd_sock.net_index = consumer->net_seq_index;
1044         msg.u.relayd_sock.type = type;
1045         msg.u.relayd_sock.session_id = session_id;
1046         memcpy(&msg.u.relayd_sock.sock, rsock, sizeof(msg.u.relayd_sock.sock));
1047
1048         DBG3("Sending relayd sock info to consumer on %d", *consumer_sock->fd_ptr);
1049         ret = consumer_send_msg(consumer_sock, &msg);
1050         if (ret < 0) {
1051                 goto error;
1052         }
1053
1054         DBG3("Sending relayd socket file descriptor to consumer");
1055         ret = consumer_send_fds(consumer_sock, &rsock->sock.fd, 1);
1056         if (ret < 0) {
1057                 goto error;
1058         }
1059
1060         DBG2("Consumer relayd socket sent");
1061
1062 error:
1063         return ret;
1064 }
1065
1066 int consumer_send_channel_monitor_pipe(struct consumer_socket *consumer_sock,
1067                 int pipe)
1068 {
1069         int ret;
1070         struct lttcomm_consumer_msg msg;
1071
1072         /* Code flow error. Safety net. */
1073
1074         memset(&msg, 0, sizeof(msg));
1075         msg.cmd_type = LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE;
1076
1077         pthread_mutex_lock(consumer_sock->lock);
1078         DBG3("Sending set_channel_monitor_pipe command to consumer");
1079         ret = consumer_send_msg(consumer_sock, &msg);
1080         if (ret < 0) {
1081                 goto error;
1082         }
1083
1084         DBG3("Sending channel monitoring pipe %d to consumer on socket %d",
1085                         pipe, *consumer_sock->fd_ptr);
1086         ret = consumer_send_fds(consumer_sock, &pipe, 1);
1087         if (ret < 0) {
1088                 goto error;
1089         }
1090
1091         DBG2("Channel monitoring pipe successfully sent");
1092 error:
1093         pthread_mutex_unlock(consumer_sock->lock);
1094         return ret;
1095 }
1096
1097 /*
1098  * Set consumer subdirectory using the session name and a generated datetime if
1099  * needed. This is appended to the current subdirectory.
1100  */
1101 int consumer_set_subdir(struct consumer_output *consumer,
1102                 const char *session_name)
1103 {
1104         int ret = 0;
1105         unsigned int have_default_name = 0;
1106         char datetime[16], tmp_path[PATH_MAX];
1107         time_t rawtime;
1108         struct tm *timeinfo;
1109
1110         assert(consumer);
1111         assert(session_name);
1112
1113         memset(tmp_path, 0, sizeof(tmp_path));
1114
1115         /* Flag if we have a default session. */
1116         if (strncmp(session_name, DEFAULT_SESSION_NAME "-",
1117                                 strlen(DEFAULT_SESSION_NAME) + 1) == 0) {
1118                 have_default_name = 1;
1119         } else {
1120                 /* Get date and time for session path */
1121                 time(&rawtime);
1122                 timeinfo = localtime(&rawtime);
1123                 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
1124         }
1125
1126         if (have_default_name) {
1127                 ret = snprintf(tmp_path, sizeof(tmp_path),
1128                                 "%s/%s", consumer->subdir, session_name);
1129         } else {
1130                 ret = snprintf(tmp_path, sizeof(tmp_path),
1131                                 "%s/%s-%s/", consumer->subdir, session_name, datetime);
1132         }
1133         if (ret < 0) {
1134                 PERROR("snprintf session name date");
1135                 goto error;
1136         }
1137
1138         if (lttng_strncpy(consumer->subdir, tmp_path,
1139                         sizeof(consumer->subdir))) {
1140                 ret = -EINVAL;
1141                 goto error;
1142         }
1143         DBG2("Consumer subdir set to %s", consumer->subdir);
1144
1145 error:
1146         return ret;
1147 }
1148
1149 /*
1150  * Ask the consumer if the data is pending for the specific session id.
1151  * Returns 1 if data is pending, 0 otherwise, or < 0 on error.
1152  */
1153 int consumer_is_data_pending(uint64_t session_id,
1154                 struct consumer_output *consumer)
1155 {
1156         int ret;
1157         int32_t ret_code = 0;  /* Default is that the data is NOT pending */
1158         struct consumer_socket *socket;
1159         struct lttng_ht_iter iter;
1160         struct lttcomm_consumer_msg msg;
1161
1162         assert(consumer);
1163
1164         DBG3("Consumer data pending for id %" PRIu64, session_id);
1165
1166         memset(&msg, 0, sizeof(msg));
1167         msg.cmd_type = LTTNG_CONSUMER_DATA_PENDING;
1168         msg.u.data_pending.session_id = session_id;
1169
1170         /* Send command for each consumer */
1171         rcu_read_lock();
1172         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1173                         node.node) {
1174                 pthread_mutex_lock(socket->lock);
1175                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1176                 if (ret < 0) {
1177                         pthread_mutex_unlock(socket->lock);
1178                         goto error_unlock;
1179                 }
1180
1181                 /*
1182                  * No need for a recv reply status because the answer to the command is
1183                  * the reply status message.
1184                  */
1185
1186                 ret = consumer_socket_recv(socket, &ret_code, sizeof(ret_code));
1187                 if (ret < 0) {
1188                         pthread_mutex_unlock(socket->lock);
1189                         goto error_unlock;
1190                 }
1191                 pthread_mutex_unlock(socket->lock);
1192
1193                 if (ret_code == 1) {
1194                         break;
1195                 }
1196         }
1197         rcu_read_unlock();
1198
1199         DBG("Consumer data is %s pending for session id %" PRIu64,
1200                         ret_code == 1 ? "" : "NOT", session_id);
1201         return ret_code;
1202
1203 error_unlock:
1204         rcu_read_unlock();
1205         return -1;
1206 }
1207
1208 /*
1209  * Send a flush command to consumer using the given channel key.
1210  *
1211  * Return 0 on success else a negative value.
1212  */
1213 int consumer_flush_channel(struct consumer_socket *socket, uint64_t key)
1214 {
1215         int ret;
1216         struct lttcomm_consumer_msg msg;
1217
1218         assert(socket);
1219
1220         DBG2("Consumer flush channel key %" PRIu64, key);
1221
1222         memset(&msg, 0, sizeof(msg));
1223         msg.cmd_type = LTTNG_CONSUMER_FLUSH_CHANNEL;
1224         msg.u.flush_channel.key = key;
1225
1226         pthread_mutex_lock(socket->lock);
1227         health_code_update();
1228
1229         ret = consumer_send_msg(socket, &msg);
1230         if (ret < 0) {
1231                 goto end;
1232         }
1233
1234 end:
1235         health_code_update();
1236         pthread_mutex_unlock(socket->lock);
1237         return ret;
1238 }
1239
1240 /*
1241  * Send a clear quiescent command to consumer using the given channel key.
1242  *
1243  * Return 0 on success else a negative value.
1244  */
1245 int consumer_clear_quiescent_channel(struct consumer_socket *socket, uint64_t key)
1246 {
1247         int ret;
1248         struct lttcomm_consumer_msg msg;
1249
1250         assert(socket);
1251
1252         DBG2("Consumer clear quiescent channel key %" PRIu64, key);
1253
1254         memset(&msg, 0, sizeof(msg));
1255         msg.cmd_type = LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL;
1256         msg.u.clear_quiescent_channel.key = key;
1257
1258         pthread_mutex_lock(socket->lock);
1259         health_code_update();
1260
1261         ret = consumer_send_msg(socket, &msg);
1262         if (ret < 0) {
1263                 goto end;
1264         }
1265
1266 end:
1267         health_code_update();
1268         pthread_mutex_unlock(socket->lock);
1269         return ret;
1270 }
1271
1272 /*
1273  * Send a close metadata command to consumer using the given channel key.
1274  * Called with registry lock held.
1275  *
1276  * Return 0 on success else a negative value.
1277  */
1278 int consumer_close_metadata(struct consumer_socket *socket,
1279                 uint64_t metadata_key)
1280 {
1281         int ret;
1282         struct lttcomm_consumer_msg msg;
1283
1284         assert(socket);
1285
1286         DBG2("Consumer close metadata channel key %" PRIu64, metadata_key);
1287
1288         memset(&msg, 0, sizeof(msg));
1289         msg.cmd_type = LTTNG_CONSUMER_CLOSE_METADATA;
1290         msg.u.close_metadata.key = metadata_key;
1291
1292         pthread_mutex_lock(socket->lock);
1293         health_code_update();
1294
1295         ret = consumer_send_msg(socket, &msg);
1296         if (ret < 0) {
1297                 goto end;
1298         }
1299
1300 end:
1301         health_code_update();
1302         pthread_mutex_unlock(socket->lock);
1303         return ret;
1304 }
1305
1306 /*
1307  * Send a setup metdata command to consumer using the given channel key.
1308  *
1309  * Return 0 on success else a negative value.
1310  */
1311 int consumer_setup_metadata(struct consumer_socket *socket,
1312                 uint64_t metadata_key)
1313 {
1314         int ret;
1315         struct lttcomm_consumer_msg msg;
1316
1317         assert(socket);
1318
1319         DBG2("Consumer setup metadata channel key %" PRIu64, metadata_key);
1320
1321         memset(&msg, 0, sizeof(msg));
1322         msg.cmd_type = LTTNG_CONSUMER_SETUP_METADATA;
1323         msg.u.setup_metadata.key = metadata_key;
1324
1325         pthread_mutex_lock(socket->lock);
1326         health_code_update();
1327
1328         ret = consumer_send_msg(socket, &msg);
1329         if (ret < 0) {
1330                 goto end;
1331         }
1332
1333 end:
1334         health_code_update();
1335         pthread_mutex_unlock(socket->lock);
1336         return ret;
1337 }
1338
1339 /*
1340  * Send metadata string to consumer.
1341  * RCU read-side lock must be held to guarantee existence of socket.
1342  *
1343  * Return 0 on success else a negative value.
1344  */
1345 int consumer_push_metadata(struct consumer_socket *socket,
1346                 uint64_t metadata_key, char *metadata_str, size_t len,
1347                 size_t target_offset, uint64_t version)
1348 {
1349         int ret;
1350         struct lttcomm_consumer_msg msg;
1351
1352         assert(socket);
1353
1354         DBG2("Consumer push metadata to consumer socket %d", *socket->fd_ptr);
1355
1356         pthread_mutex_lock(socket->lock);
1357
1358         memset(&msg, 0, sizeof(msg));
1359         msg.cmd_type = LTTNG_CONSUMER_PUSH_METADATA;
1360         msg.u.push_metadata.key = metadata_key;
1361         msg.u.push_metadata.target_offset = target_offset;
1362         msg.u.push_metadata.len = len;
1363         msg.u.push_metadata.version = version;
1364
1365         health_code_update();
1366         ret = consumer_send_msg(socket, &msg);
1367         if (ret < 0 || len == 0) {
1368                 goto end;
1369         }
1370
1371         DBG3("Consumer pushing metadata on sock %d of len %zu", *socket->fd_ptr,
1372                         len);
1373
1374         ret = consumer_socket_send(socket, metadata_str, len);
1375         if (ret < 0) {
1376                 goto end;
1377         }
1378
1379         health_code_update();
1380         ret = consumer_recv_status_reply(socket);
1381         if (ret < 0) {
1382                 goto end;
1383         }
1384
1385 end:
1386         pthread_mutex_unlock(socket->lock);
1387         health_code_update();
1388         return ret;
1389 }
1390
1391 /*
1392  * Ask the consumer to snapshot a specific channel using the key.
1393  *
1394  * Return 0 on success or else a negative error.
1395  */
1396 int consumer_snapshot_channel(struct consumer_socket *socket, uint64_t key,
1397                 struct snapshot_output *output, int metadata, uid_t uid, gid_t gid,
1398                 const char *session_path, int wait, uint64_t nb_packets_per_stream)
1399 {
1400         int ret;
1401         struct lttcomm_consumer_msg msg;
1402
1403         assert(socket);
1404         assert(output);
1405         assert(output->consumer);
1406
1407         DBG("Consumer snapshot channel key %" PRIu64, key);
1408
1409         memset(&msg, 0, sizeof(msg));
1410         msg.cmd_type = LTTNG_CONSUMER_SNAPSHOT_CHANNEL;
1411         msg.u.snapshot_channel.key = key;
1412         msg.u.snapshot_channel.nb_packets_per_stream = nb_packets_per_stream;
1413         msg.u.snapshot_channel.metadata = metadata;
1414
1415         if (output->consumer->type == CONSUMER_DST_NET) {
1416                 msg.u.snapshot_channel.relayd_id = output->consumer->net_seq_index;
1417                 msg.u.snapshot_channel.use_relayd = 1;
1418                 ret = snprintf(msg.u.snapshot_channel.pathname,
1419                                 sizeof(msg.u.snapshot_channel.pathname),
1420                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->subdir,
1421                                 output->name, output->datetime, output->nb_snapshot,
1422                                 session_path);
1423                 if (ret < 0) {
1424                         ret = -LTTNG_ERR_NOMEM;
1425                         goto error;
1426                 }
1427         } else {
1428                 ret = snprintf(msg.u.snapshot_channel.pathname,
1429                                 sizeof(msg.u.snapshot_channel.pathname),
1430                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->dst.trace_path,
1431                                 output->name, output->datetime, output->nb_snapshot,
1432                                 session_path);
1433                 if (ret < 0) {
1434                         ret = -LTTNG_ERR_NOMEM;
1435                         goto error;
1436                 }
1437                 msg.u.snapshot_channel.relayd_id = (uint64_t) -1ULL;
1438
1439                 /* Create directory. Ignore if exist. */
1440                 ret = run_as_mkdir_recursive(msg.u.snapshot_channel.pathname,
1441                                 S_IRWXU | S_IRWXG, uid, gid);
1442                 if (ret < 0) {
1443                         if (errno != EEXIST) {
1444                                 ERR("Trace directory creation error");
1445                                 goto error;
1446                         }
1447                 }
1448         }
1449
1450         health_code_update();
1451         pthread_mutex_lock(socket->lock);
1452         ret = consumer_send_msg(socket, &msg);
1453         pthread_mutex_unlock(socket->lock);
1454         if (ret < 0) {
1455                 goto error;
1456         }
1457
1458 error:
1459         health_code_update();
1460         return ret;
1461 }
1462
1463 /*
1464  * Ask the consumer the number of discarded events for a channel.
1465  */
1466 int consumer_get_discarded_events(uint64_t session_id, uint64_t channel_key,
1467                 struct consumer_output *consumer, uint64_t *discarded)
1468 {
1469         int ret;
1470         struct consumer_socket *socket;
1471         struct lttng_ht_iter iter;
1472         struct lttcomm_consumer_msg msg;
1473
1474         assert(consumer);
1475
1476         DBG3("Consumer discarded events id %" PRIu64, session_id);
1477
1478         memset(&msg, 0, sizeof(msg));
1479         msg.cmd_type = LTTNG_CONSUMER_DISCARDED_EVENTS;
1480         msg.u.discarded_events.session_id = session_id;
1481         msg.u.discarded_events.channel_key = channel_key;
1482
1483         *discarded = 0;
1484
1485         /* Send command for each consumer */
1486         rcu_read_lock();
1487         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1488                         node.node) {
1489                 uint64_t consumer_discarded = 0;
1490                 pthread_mutex_lock(socket->lock);
1491                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1492                 if (ret < 0) {
1493                         pthread_mutex_unlock(socket->lock);
1494                         goto end;
1495                 }
1496
1497                 /*
1498                  * No need for a recv reply status because the answer to the
1499                  * command is the reply status message.
1500                  */
1501                 ret = consumer_socket_recv(socket, &consumer_discarded,
1502                                 sizeof(consumer_discarded));
1503                 if (ret < 0) {
1504                         ERR("get discarded events");
1505                         pthread_mutex_unlock(socket->lock);
1506                         goto end;
1507                 }
1508                 pthread_mutex_unlock(socket->lock);
1509                 *discarded += consumer_discarded;
1510         }
1511         ret = 0;
1512         DBG("Consumer discarded %" PRIu64 " events in session id %" PRIu64,
1513                         *discarded, session_id);
1514
1515 end:
1516         rcu_read_unlock();
1517         return ret;
1518 }
1519
1520 /*
1521  * Ask the consumer the number of lost packets for a channel.
1522  */
1523 int consumer_get_lost_packets(uint64_t session_id, uint64_t channel_key,
1524                 struct consumer_output *consumer, uint64_t *lost)
1525 {
1526         int ret;
1527         struct consumer_socket *socket;
1528         struct lttng_ht_iter iter;
1529         struct lttcomm_consumer_msg msg;
1530
1531         assert(consumer);
1532
1533         DBG3("Consumer lost packets id %" PRIu64, session_id);
1534
1535         memset(&msg, 0, sizeof(msg));
1536         msg.cmd_type = LTTNG_CONSUMER_LOST_PACKETS;
1537         msg.u.lost_packets.session_id = session_id;
1538         msg.u.lost_packets.channel_key = channel_key;
1539
1540         *lost = 0;
1541
1542         /* Send command for each consumer */
1543         rcu_read_lock();
1544         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1545                         node.node) {
1546                 uint64_t consumer_lost = 0;
1547                 pthread_mutex_lock(socket->lock);
1548                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1549                 if (ret < 0) {
1550                         pthread_mutex_unlock(socket->lock);
1551                         goto end;
1552                 }
1553
1554                 /*
1555                  * No need for a recv reply status because the answer to the
1556                  * command is the reply status message.
1557                  */
1558                 ret = consumer_socket_recv(socket, &consumer_lost,
1559                                 sizeof(consumer_lost));
1560                 if (ret < 0) {
1561                         ERR("get lost packets");
1562                         pthread_mutex_unlock(socket->lock);
1563                         goto end;
1564                 }
1565                 pthread_mutex_unlock(socket->lock);
1566                 *lost += consumer_lost;
1567         }
1568         ret = 0;
1569         DBG("Consumer lost %" PRIu64 " packets in session id %" PRIu64,
1570                         *lost, session_id);
1571
1572 end:
1573         rcu_read_unlock();
1574         return ret;
1575 }