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         }
 151
 152 end:
 153         return ret;
 154 }
 155
 156 /*
 157  * Once the ASK_CHANNEL command is sent to the consumer, the channel
 158  * information are sent back. This call receives that data and populates key
 159  * and stream_count.
 160  *
 161  * On success return 0 and both key and stream_count are set. On error, a
 162  * negative value is sent back and both parameters are untouched.
 163  */
 164 int consumer_recv_status_channel(struct consumer_socket *sock,
 165                 uint64_t *key, unsigned int *stream_count)
 166 {
 167         int ret;
 168         struct lttcomm_consumer_status_channel reply;
 169
 170         assert(sock);
 171         assert(stream_count);
 172         assert(key);
 173
 174         ret = consumer_socket_recv(sock, &reply, sizeof(reply));
 175         if (ret < 0) {
 176                 goto end;
 177         }
 178
 179         /* An error is possible so don't touch the key and stream_count. */
 180         if (reply.ret_code != LTTCOMM_CONSUMERD_SUCCESS) {
 181                 ret = -1;
 182                 goto end;
 183         }
 184
 185         *key = reply.key;
 186         *stream_count = reply.stream_count;
 187         ret = 0;
 188
 189 end:
 190         return ret;
 191 }
 192
 193 /*
 194  * Send destroy relayd command to consumer.
 195  *
 196  * On success return positive value. On error, negative value.
 197  */
 198 int consumer_send_destroy_relayd(struct consumer_socket *sock,
 199                 struct consumer_output *consumer)
 200 {
 201         int ret;
 202         struct lttcomm_consumer_msg msg;
 203
 204         assert(consumer);
 205         assert(sock);
 206
 207         DBG2("Sending destroy relayd command to consumer sock %d", *sock->fd_ptr);
 208
 209         memset(&msg, 0, sizeof(msg));
 210         msg.cmd_type = LTTNG_CONSUMER_DESTROY_RELAYD;
 211         msg.u.destroy_relayd.net_seq_idx = consumer->net_seq_index;
 212
 213         pthread_mutex_lock(sock->lock);
 214         ret = consumer_socket_send(sock, &msg, sizeof(msg));
 215         if (ret < 0) {
 216                 goto error;
 217         }
 218
 219         /* Don't check the return value. The caller will do it. */
 220         ret = consumer_recv_status_reply(sock);
 221
 222         DBG2("Consumer send destroy relayd command done");
 223
 224 error:
 225         pthread_mutex_unlock(sock->lock);
 226         return ret;
 227 }
 228
 229 /*
 230  * For each consumer socket in the consumer output object, send a destroy
 231  * relayd command.
 232  */
 233 void consumer_output_send_destroy_relayd(struct consumer_output *consumer)
 234 {
 235         struct lttng_ht_iter iter;
 236         struct consumer_socket *socket;
 237
 238         assert(consumer);
 239
 240         /* Destroy any relayd connection */
 241         if (consumer->type == CONSUMER_DST_NET) {
 242                 rcu_read_lock();
 243                 cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
 244                                 node.node) {
 245                         int ret;
 246
 247                         /* Send destroy relayd command */
 248                         ret = consumer_send_destroy_relayd(socket, consumer);
 249                         if (ret < 0) {
 250                                 DBG("Unable to send destroy relayd command to consumer");
 251                                 /* Continue since we MUST delete everything at this point. */
 252                         }
 253                 }
 254                 rcu_read_unlock();
 255         }
 256 }
 257
 258 /*
 259  * From a consumer_data structure, allocate and add a consumer socket to the
 260  * consumer output.
 261  *
 262  * Return 0 on success, else negative value on error
 263  */
 264 int consumer_create_socket(struct consumer_data *data,
 265                 struct consumer_output *output)
 266 {
 267         int ret = 0;
 268         struct consumer_socket *socket;
 269
 270         assert(data);
 271
 272         if (output == NULL || data->cmd_sock < 0) {
 273                 /*
 274                  * Not an error. Possible there is simply not spawned consumer or it's
 275                  * disabled for the tracing session asking the socket.
 276                  */
 277                 goto error;
 278         }
 279
 280         rcu_read_lock();
 281         socket = consumer_find_socket(data->cmd_sock, output);
 282         rcu_read_unlock();
 283         if (socket == NULL) {
 284                 socket = consumer_allocate_socket(&data->cmd_sock);
 285                 if (socket == NULL) {
 286                         ret = -1;
 287                         goto error;
 288                 }
 289
 290                 socket->registered = 0;
 291                 socket->lock = &data->lock;
 292                 rcu_read_lock();
 293                 consumer_add_socket(socket, output);
 294                 rcu_read_unlock();
 295         }
 296
 297         socket->type = data->type;
 298
 299         DBG3("Consumer socket created (fd: %d) and added to output",
 300                         data->cmd_sock);
 301
 302 error:
 303         return ret;
 304 }
 305
 306 /*
 307  * Return the consumer socket from the given consumer output with the right
 308  * bitness. On error, returns NULL.
 309  *
 310  * The caller MUST acquire a rcu read side lock and keep it until the socket
 311  * object reference is not needed anymore.
 312  */
 313 struct consumer_socket *consumer_find_socket_by_bitness(int bits,
 314                 struct consumer_output *consumer)
 315 {
 316         int consumer_fd;
 317         struct consumer_socket *socket = NULL;
 318
 319         switch (bits) {
 320         case 64:
 321                 consumer_fd = uatomic_read(&ust_consumerd64_fd);
 322                 break;
 323         case 32:
 324                 consumer_fd = uatomic_read(&ust_consumerd32_fd);
 325                 break;
 326         default:
 327                 assert(0);
 328                 goto end;
 329         }
 330
 331         socket = consumer_find_socket(consumer_fd, consumer);
 332         if (!socket) {
 333                 ERR("Consumer socket fd %d not found in consumer obj %p",
 334                                 consumer_fd, consumer);
 335         }
 336
 337 end:
 338         return socket;
 339 }
 340
 341 /*
 342  * Find a consumer_socket in a consumer_output hashtable. Read side lock must
 343  * be acquired before calling this function and across use of the
 344  * returned consumer_socket.
 345  */
 346 struct consumer_socket *consumer_find_socket(int key,
 347                 struct consumer_output *consumer)
 348 {
 349         struct lttng_ht_iter iter;
 350         struct lttng_ht_node_ulong *node;
 351         struct consumer_socket *socket = NULL;
 352
 353         /* Negative keys are lookup failures */
 354         if (key < 0 || consumer == NULL) {
 355                 return NULL;
 356         }
 357
 358         lttng_ht_lookup(consumer->socks, (void *)((unsigned long) key),
 359                         &iter);
 360         node = lttng_ht_iter_get_node_ulong(&iter);
 361         if (node != NULL) {
 362                 socket = caa_container_of(node, struct consumer_socket, node);
 363         }
 364
 365         return socket;
 366 }
 367
 368 /*
 369  * Allocate a new consumer_socket and return the pointer.
 370  */
 371 struct consumer_socket *consumer_allocate_socket(int *fd)
 372 {
 373         struct consumer_socket *socket = NULL;
 374
 375         assert(fd);
 376
 377         socket = zmalloc(sizeof(struct consumer_socket));
 378         if (socket == NULL) {
 379                 PERROR("zmalloc consumer socket");
 380                 goto error;
 381         }
 382
 383         socket->fd_ptr = fd;
 384         lttng_ht_node_init_ulong(&socket->node, *fd);
 385
 386 error:
 387         return socket;
 388 }
 389
 390 /*
 391  * Add consumer socket to consumer output object. Read side lock must be
 392  * acquired before calling this function.
 393  */
 394 void consumer_add_socket(struct consumer_socket *sock,
 395                 struct consumer_output *consumer)
 396 {
 397         assert(sock);
 398         assert(consumer);
 399
 400         lttng_ht_add_unique_ulong(consumer->socks, &sock->node);
 401 }
 402
 403 /*
 404  * Delte consumer socket to consumer output object. Read side lock must be
 405  * acquired before calling this function.
 406  */
 407 void consumer_del_socket(struct consumer_socket *sock,
 408                 struct consumer_output *consumer)
 409 {
 410         int ret;
 411         struct lttng_ht_iter iter;
 412
 413         assert(sock);
 414         assert(consumer);
 415
 416         iter.iter.node = &sock->node.node;
 417         ret = lttng_ht_del(consumer->socks, &iter);
 418         assert(!ret);
 419 }
 420
 421 /*
 422  * RCU destroy call function.
 423  */
 424 static void destroy_socket_rcu(struct rcu_head *head)
 425 {
 426         struct lttng_ht_node_ulong *node =
 427                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 428         struct consumer_socket *socket =
 429                 caa_container_of(node, struct consumer_socket, node);
 430
 431         free(socket);
 432 }
 433
 434 /*
 435  * Destroy and free socket pointer in a call RCU. Read side lock must be
 436  * acquired before calling this function.
 437  */
 438 void consumer_destroy_socket(struct consumer_socket *sock)
 439 {
 440         assert(sock);
 441
 442         /*
 443          * We DO NOT close the file descriptor here since it is global to the
 444          * session daemon and is closed only if the consumer dies or a custom
 445          * consumer was registered,
 446          */
 447         if (sock->registered) {
 448                 DBG3("Consumer socket was registered. Closing fd %d", *sock->fd_ptr);
 449                 lttcomm_close_unix_sock(*sock->fd_ptr);
 450         }
 451
 452         call_rcu(&sock->node.head, destroy_socket_rcu);
 453 }
 454
 455 /*
 456  * Allocate and assign data to a consumer_output object.
 457  *
 458  * Return pointer to structure.
 459  */
 460 struct consumer_output *consumer_create_output(enum consumer_dst_type type)
 461 {
 462         struct consumer_output *output = NULL;
 463
 464         output = zmalloc(sizeof(struct consumer_output));
 465         if (output == NULL) {
 466                 PERROR("zmalloc consumer_output");
 467                 goto error;
 468         }
 469
 470         /* By default, consumer output is enabled */
 471         output->enabled = 1;
 472         output->type = type;
 473         output->net_seq_index = (uint64_t) -1ULL;
 474         urcu_ref_init(&output->ref);
 475
 476         output->socks = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 477
 478 error:
 479         return output;
 480 }
 481
 482 /*
 483  * Iterate over the consumer output socket hash table and destroy them. The
 484  * socket file descriptor are only closed if the consumer output was
 485  * registered meaning it's an external consumer.
 486  */
 487 void consumer_destroy_output_sockets(struct consumer_output *obj)
 488 {
 489         struct lttng_ht_iter iter;
 490         struct consumer_socket *socket;
 491
 492         if (!obj->socks) {
 493                 return;
 494         }
 495
 496         rcu_read_lock();
 497         cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 498                 consumer_del_socket(socket, obj);
 499                 consumer_destroy_socket(socket);
 500         }
 501         rcu_read_unlock();
 502 }
 503
 504 /*
 505  * Delete the consumer_output object from the list and free the ptr.
 506  *
 507  * Should *NOT* be called with RCU read-side lock held.
 508  */
 509 static void consumer_release_output(struct urcu_ref *ref)
 510 {
 511         struct consumer_output *obj =
 512                 caa_container_of(ref, struct consumer_output, ref);
 513
 514         consumer_destroy_output_sockets(obj);
 515
 516         if (obj->socks) {
 517                 /* Finally destroy HT */
 518                 ht_cleanup_push(obj->socks);
 519         }
 520
 521         free(obj);
 522 }
 523
 524 /*
 525  * Get the consumer_output object.
 526  */
 527 void consumer_output_get(struct consumer_output *obj)
 528 {
 529         urcu_ref_get(&obj->ref);
 530 }
 531
 532 /*
 533  * Put the consumer_output object.
 534  *
 535  * Should *NOT* be called with RCU read-side lock held.
 536  */
 537 void consumer_output_put(struct consumer_output *obj)
 538 {
 539         if (!obj) {
 540                 return;
 541         }
 542         urcu_ref_put(&obj->ref, consumer_release_output);
 543 }
 544
 545 /*
 546  * Copy consumer output and returned the newly allocated copy.
 547  *
 548  * Should *NOT* be called with RCU read-side lock held.
 549  */
 550 struct consumer_output *consumer_copy_output(struct consumer_output *obj)
 551 {
 552         int ret;
 553         struct consumer_output *output;
 554
 555         assert(obj);
 556
 557         output = consumer_create_output(obj->type);
 558         if (output == NULL) {
 559                 goto end;
 560         }
 561         output->enabled = obj->enabled;
 562         output->net_seq_index = obj->net_seq_index;
 563         memcpy(output->subdir, obj->subdir, PATH_MAX);
 564         output->snapshot = obj->snapshot;
 565         output->relay_major_version = obj->relay_major_version;
 566         output->relay_minor_version = obj->relay_minor_version;
 567         memcpy(&output->dst, &obj->dst, sizeof(output->dst));
 568         ret = consumer_copy_sockets(output, obj);
 569         if (ret < 0) {
 570                 goto error_put;
 571         }
 572 end:
 573         return output;
 574
 575 error_put:
 576         consumer_output_put(output);
 577         return NULL;
 578 }
 579
 580 /*
 581  * Copy consumer sockets from src to dst.
 582  *
 583  * Return 0 on success or else a negative value.
 584  */
 585 int consumer_copy_sockets(struct consumer_output *dst,
 586                 struct consumer_output *src)
 587 {
 588         int ret = 0;
 589         struct lttng_ht_iter iter;
 590         struct consumer_socket *socket, *copy_sock;
 591
 592         assert(dst);
 593         assert(src);
 594
 595         rcu_read_lock();
 596         cds_lfht_for_each_entry(src->socks->ht, &iter.iter, socket, node.node) {
 597                 /* Ignore socket that are already there. */
 598                 copy_sock = consumer_find_socket(*socket->fd_ptr, dst);
 599                 if (copy_sock) {
 600                         continue;
 601                 }
 602
 603                 /* Create new socket object. */
 604                 copy_sock = consumer_allocate_socket(socket->fd_ptr);
 605                 if (copy_sock == NULL) {
 606                         rcu_read_unlock();
 607                         ret = -ENOMEM;
 608                         goto error;
 609                 }
 610
 611                 copy_sock->registered = socket->registered;
 612                 /*
 613                  * This is valid because this lock is shared accross all consumer
 614                  * object being the global lock of the consumer data structure of the
 615                  * session daemon.
 616                  */
 617                 copy_sock->lock = socket->lock;
 618                 consumer_add_socket(copy_sock, dst);
 619         }
 620         rcu_read_unlock();
 621
 622 error:
 623         return ret;
 624 }
 625
 626 /*
 627  * Set network URI to the consumer output object.
 628  *
 629  * Return 0 on success. Return 1 if the URI were equal. Else, negative value on
 630  * error.
 631  */
 632 int consumer_set_network_uri(struct consumer_output *obj,
 633                 struct lttng_uri *uri)
 634 {
 635         int ret;
 636         char tmp_path[PATH_MAX];
 637         char hostname[HOST_NAME_MAX];
 638         struct lttng_uri *dst_uri = NULL;
 639
 640         /* Code flow error safety net. */
 641         assert(obj);
 642         assert(uri);
 643
 644         switch (uri->stype) {
 645         case LTTNG_STREAM_CONTROL:
 646                 dst_uri = &obj->dst.net.control;
 647                 obj->dst.net.control_isset = 1;
 648                 if (uri->port == 0) {
 649                         /* Assign default port. */
 650                         uri->port = DEFAULT_NETWORK_CONTROL_PORT;
 651                 } else {
 652                         if (obj->dst.net.data_isset && uri->port ==
 653                                         obj->dst.net.data.port) {
 654                                 ret = -LTTNG_ERR_INVALID;
 655                                 goto error;
 656                         }
 657                 }
 658                 DBG3("Consumer control URI set with port %d", uri->port);
 659                 break;
 660         case LTTNG_STREAM_DATA:
 661                 dst_uri = &obj->dst.net.data;
 662                 obj->dst.net.data_isset = 1;
 663                 if (uri->port == 0) {
 664                         /* Assign default port. */
 665                         uri->port = DEFAULT_NETWORK_DATA_PORT;
 666                 } else {
 667                         if (obj->dst.net.control_isset && uri->port ==
 668                                         obj->dst.net.control.port) {
 669                                 ret = -LTTNG_ERR_INVALID;
 670                                 goto error;
 671                         }
 672                 }
 673                 DBG3("Consumer data URI set with port %d", uri->port);
 674                 break;
 675         default:
 676                 ERR("Set network uri type unknown %d", uri->stype);
 677                 ret = -LTTNG_ERR_INVALID;
 678                 goto error;
 679         }
 680
 681         ret = uri_compare(dst_uri, uri);
 682         if (!ret) {
 683                 /* Same URI, don't touch it and return success. */
 684                 DBG3("URI network compare are the same");
 685                 goto equal;
 686         }
 687
 688         /* URIs were not equal, replacing it. */
 689         memset(dst_uri, 0, sizeof(struct lttng_uri));
 690         memcpy(dst_uri, uri, sizeof(struct lttng_uri));
 691         obj->type = CONSUMER_DST_NET;
 692
 693         /* Handle subdir and add hostname in front. */
 694         if (dst_uri->stype == LTTNG_STREAM_CONTROL) {
 695                 /* Get hostname to append it in the pathname */
 696                 ret = gethostname(hostname, sizeof(hostname));
 697                 if (ret < 0) {
 698                         PERROR("gethostname. Fallback on default localhost");
 699                         strncpy(hostname, "localhost", sizeof(hostname));
 700                 }
 701                 hostname[sizeof(hostname) - 1] = '\0';
 702
 703                 /* Setup consumer subdir if none present in the control URI */
 704                 if (strlen(dst_uri->subdir) == 0) {
 705                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 706                                         hostname, obj->subdir);
 707                 } else {
 708                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 709                                         hostname, dst_uri->subdir);
 710                 }
 711                 if (ret < 0) {
 712                         PERROR("snprintf set consumer uri subdir");
 713                         ret = -LTTNG_ERR_NOMEM;
 714                         goto error;
 715                 }
 716
 717                 if (lttng_strncpy(obj->subdir, tmp_path, sizeof(obj->subdir))) {
 718                         ret = -LTTNG_ERR_INVALID;
 719                         goto error;
 720                 }
 721                 DBG3("Consumer set network uri subdir path %s", tmp_path);
 722         }
 723
 724         return 0;
 725 equal:
 726         return 1;
 727 error:
 728         return ret;
 729 }
 730
 731 /*
 732  * Send file descriptor to consumer via sock.
 733  *
 734  * The consumer socket lock must be held by the caller.
 735  */
 736 int consumer_send_fds(struct consumer_socket *sock, int *fds, size_t nb_fd)
 737 {
 738         int ret;
 739
 740         assert(fds);
 741         assert(sock);
 742         assert(nb_fd > 0);
 743         assert(pthread_mutex_trylock(sock->lock) == EBUSY);
 744
 745         ret = lttcomm_send_fds_unix_sock(*sock->fd_ptr, fds, nb_fd);
 746         if (ret < 0) {
 747                 /* The above call will print a PERROR on error. */
 748                 DBG("Error when sending consumer fds on sock %d", *sock->fd_ptr);
 749                 goto error;
 750         }
 751
 752         ret = consumer_recv_status_reply(sock);
 753 error:
 754         return ret;
 755 }
 756
 757 /*
 758  * Consumer send communication message structure to consumer.
 759  *
 760  * The consumer socket lock must be held by the caller.
 761  */
 762 int consumer_send_msg(struct consumer_socket *sock,
 763                 struct lttcomm_consumer_msg *msg)
 764 {
 765         int ret;
 766
 767         assert(msg);
 768         assert(sock);
 769         assert(pthread_mutex_trylock(sock->lock) == EBUSY);
 770
 771         ret = consumer_socket_send(sock, msg, sizeof(struct lttcomm_consumer_msg));
 772         if (ret < 0) {
 773                 goto error;
 774         }
 775
 776         ret = consumer_recv_status_reply(sock);
 777
 778 error:
 779         return ret;
 780 }
 781
 782 /*
 783  * Consumer send channel communication message structure to consumer.
 784  *
 785  * The consumer socket lock must be held by the caller.
 786  */
 787 int consumer_send_channel(struct consumer_socket *sock,
 788                 struct lttcomm_consumer_msg *msg)
 789 {
 790         int ret;
 791
 792         assert(msg);
 793         assert(sock);
 794
 795         ret = consumer_send_msg(sock, msg);
 796         if (ret < 0) {
 797                 goto error;
 798         }
 799
 800 error:
 801         return ret;
 802 }
 803
 804 /*
 805  * Populate the given consumer msg structure with the ask_channel command
 806  * information.
 807  */
 808 void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 809                 uint64_t subbuf_size,
 810                 uint64_t num_subbuf,
 811                 int overwrite,
 812                 unsigned int switch_timer_interval,
 813                 unsigned int read_timer_interval,
 814                 unsigned int live_timer_interval,
 815                 unsigned int monitor_timer_interval,
 816                 int output,
 817                 int type,
 818                 uint64_t session_id,
 819                 const char *pathname,
 820                 const char *name,
 821                 uid_t uid,
 822                 gid_t gid,
 823                 uint64_t relayd_id,
 824                 uint64_t key,
 825                 unsigned char *uuid,
 826                 uint32_t chan_id,
 827                 uint64_t tracefile_size,
 828                 uint64_t tracefile_count,
 829                 uint64_t session_id_per_pid,
 830                 unsigned int monitor,
 831                 uint32_t ust_app_uid,
 832                 int64_t blocking_timeout,
 833                 const char *root_shm_path,
 834                 const char *shm_path)
 835 {
 836         assert(msg);
 837
 838         /* Zeroed structure */
 839         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 840
 841         msg->cmd_type = LTTNG_CONSUMER_ASK_CHANNEL_CREATION;
 842         msg->u.ask_channel.subbuf_size = subbuf_size;
 843         msg->u.ask_channel.num_subbuf = num_subbuf ;
 844         msg->u.ask_channel.overwrite = overwrite;
 845         msg->u.ask_channel.switch_timer_interval = switch_timer_interval;
 846         msg->u.ask_channel.read_timer_interval = read_timer_interval;
 847         msg->u.ask_channel.live_timer_interval = live_timer_interval;
 848         msg->u.ask_channel.monitor_timer_interval = monitor_timer_interval;
 849         msg->u.ask_channel.output = output;
 850         msg->u.ask_channel.type = type;
 851         msg->u.ask_channel.session_id = session_id;
 852         msg->u.ask_channel.session_id_per_pid = session_id_per_pid;
 853         msg->u.ask_channel.uid = uid;
 854         msg->u.ask_channel.gid = gid;
 855         msg->u.ask_channel.relayd_id = relayd_id;
 856         msg->u.ask_channel.key = key;
 857         msg->u.ask_channel.chan_id = chan_id;
 858         msg->u.ask_channel.tracefile_size = tracefile_size;
 859         msg->u.ask_channel.tracefile_count = tracefile_count;
 860         msg->u.ask_channel.monitor = monitor;
 861         msg->u.ask_channel.ust_app_uid = ust_app_uid;
 862         msg->u.ask_channel.blocking_timeout = blocking_timeout;
 863
 864         memcpy(msg->u.ask_channel.uuid, uuid, sizeof(msg->u.ask_channel.uuid));
 865
 866         if (pathname) {
 867                 strncpy(msg->u.ask_channel.pathname, pathname,
 868                                 sizeof(msg->u.ask_channel.pathname));
 869                 msg->u.ask_channel.pathname[sizeof(msg->u.ask_channel.pathname)-1] = '\0';
 870         }
 871
 872         strncpy(msg->u.ask_channel.name, name, sizeof(msg->u.ask_channel.name));
 873         msg->u.ask_channel.name[sizeof(msg->u.ask_channel.name) - 1] = '\0';
 874
 875         if (root_shm_path) {
 876                 strncpy(msg->u.ask_channel.root_shm_path, root_shm_path,
 877                         sizeof(msg->u.ask_channel.root_shm_path));
 878                 msg->u.ask_channel.root_shm_path[sizeof(msg->u.ask_channel.root_shm_path) - 1] = '\0';
 879         }
 880         if (shm_path) {
 881                 strncpy(msg->u.ask_channel.shm_path, shm_path,
 882                         sizeof(msg->u.ask_channel.shm_path));
 883                 msg->u.ask_channel.shm_path[sizeof(msg->u.ask_channel.shm_path) - 1] = '\0';
 884         }
 885 }
 886
 887 /*
 888  * Init channel communication message structure.
 889  */
 890 void consumer_init_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 891                 enum lttng_consumer_command cmd,
 892                 uint64_t channel_key,
 893                 uint64_t session_id,
 894                 const char *pathname,
 895                 uid_t uid,
 896                 gid_t gid,
 897                 uint64_t relayd_id,
 898                 const char *name,
 899                 unsigned int nb_init_streams,
 900                 enum lttng_event_output output,
 901                 int type,
 902                 uint64_t tracefile_size,
 903                 uint64_t tracefile_count,
 904                 unsigned int monitor,
 905                 unsigned int live_timer_interval,
 906                 unsigned int monitor_timer_interval)
 907 {
 908         assert(msg);
 909
 910         /* Zeroed structure */
 911         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 912
 913         /* Send channel */
 914         msg->cmd_type = cmd;
 915         msg->u.channel.channel_key = channel_key;
 916         msg->u.channel.session_id = session_id;
 917         msg->u.channel.uid = uid;
 918         msg->u.channel.gid = gid;
 919         msg->u.channel.relayd_id = relayd_id;
 920         msg->u.channel.nb_init_streams = nb_init_streams;
 921         msg->u.channel.output = output;
 922         msg->u.channel.type = type;
 923         msg->u.channel.tracefile_size = tracefile_size;
 924         msg->u.channel.tracefile_count = tracefile_count;
 925         msg->u.channel.monitor = monitor;
 926         msg->u.channel.live_timer_interval = live_timer_interval;
 927         msg->u.channel.monitor_timer_interval = monitor_timer_interval;
 928
 929         strncpy(msg->u.channel.pathname, pathname,
 930                         sizeof(msg->u.channel.pathname));
 931         msg->u.channel.pathname[sizeof(msg->u.channel.pathname) - 1] = '\0';
 932
 933         strncpy(msg->u.channel.name, name, sizeof(msg->u.channel.name));
 934         msg->u.channel.name[sizeof(msg->u.channel.name) - 1] = '\0';
 935 }
 936
 937 /*
 938  * Init stream communication message structure.
 939  */
 940 void consumer_init_stream_comm_msg(struct lttcomm_consumer_msg *msg,
 941                 enum lttng_consumer_command cmd,
 942                 uint64_t channel_key,
 943                 uint64_t stream_key,
 944                 int cpu)
 945 {
 946         assert(msg);
 947
 948         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 949
 950         msg->cmd_type = cmd;
 951         msg->u.stream.channel_key = channel_key;
 952         msg->u.stream.stream_key = stream_key;
 953         msg->u.stream.cpu = cpu;
 954 }
 955
 956 void consumer_init_streams_sent_comm_msg(struct lttcomm_consumer_msg *msg,
 957                 enum lttng_consumer_command cmd,
 958                 uint64_t channel_key, uint64_t net_seq_idx)
 959 {
 960         assert(msg);
 961
 962         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 963
 964         msg->cmd_type = cmd;
 965         msg->u.sent_streams.channel_key = channel_key;
 966         msg->u.sent_streams.net_seq_idx = net_seq_idx;
 967 }
 968
 969 /*
 970  * Send stream communication structure to the consumer.
 971  */
 972 int consumer_send_stream(struct consumer_socket *sock,
 973                 struct consumer_output *dst, struct lttcomm_consumer_msg *msg,
 974                 int *fds, size_t nb_fd)
 975 {
 976         int ret;
 977
 978         assert(msg);
 979         assert(dst);
 980         assert(sock);
 981         assert(fds);
 982
 983         ret = consumer_send_msg(sock, msg);
 984         if (ret < 0) {
 985                 goto error;
 986         }
 987
 988         ret = consumer_send_fds(sock, fds, nb_fd);
 989         if (ret < 0) {
 990                 goto error;
 991         }
 992
 993 error:
 994         return ret;
 995 }
 996
 997 /*
 998  * Send relayd socket to consumer associated with a session name.
 999  *
1000  * The consumer socket lock must be held by the caller.
1001  *
1002  * On success return positive value. On error, negative value.
1003  */
1004 int consumer_send_relayd_socket(struct consumer_socket *consumer_sock,
1005                 struct lttcomm_relayd_sock *rsock, struct consumer_output *consumer,
1006                 enum lttng_stream_type type, uint64_t session_id,
1007                 char *session_name, char *hostname, int session_live_timer)
1008 {
1009         int ret;
1010         struct lttcomm_consumer_msg msg;
1011
1012         /* Code flow error. Safety net. */
1013         assert(rsock);
1014         assert(consumer);
1015         assert(consumer_sock);
1016
1017         memset(&msg, 0, sizeof(msg));
1018         /* Bail out if consumer is disabled */
1019         if (!consumer->enabled) {
1020                 ret = LTTNG_OK;
1021                 goto error;
1022         }
1023
1024         if (type == LTTNG_STREAM_CONTROL) {
1025                 ret = relayd_create_session(rsock,
1026                                 &msg.u.relayd_sock.relayd_session_id,
1027                                 session_name, hostname, session_live_timer,
1028                                 consumer->snapshot);
1029                 if (ret < 0) {
1030                         /* Close the control socket. */
1031                         (void) relayd_close(rsock);
1032                         goto error;
1033                 }
1034         }
1035
1036         msg.cmd_type = LTTNG_CONSUMER_ADD_RELAYD_SOCKET;
1037         /*
1038          * Assign network consumer output index using the temporary consumer since
1039          * this call should only be made from within a set_consumer_uri() function
1040          * call in the session daemon.
1041          */
1042         msg.u.relayd_sock.net_index = consumer->net_seq_index;
1043         msg.u.relayd_sock.type = type;
1044         msg.u.relayd_sock.session_id = session_id;
1045         memcpy(&msg.u.relayd_sock.sock, rsock, sizeof(msg.u.relayd_sock.sock));
1046
1047         DBG3("Sending relayd sock info to consumer on %d", *consumer_sock->fd_ptr);
1048         ret = consumer_send_msg(consumer_sock, &msg);
1049         if (ret < 0) {
1050                 goto error;
1051         }
1052
1053         DBG3("Sending relayd socket file descriptor to consumer");
1054         ret = consumer_send_fds(consumer_sock, &rsock->sock.fd, 1);
1055         if (ret < 0) {
1056                 goto error;
1057         }
1058
1059         DBG2("Consumer relayd socket sent");
1060
1061 error:
1062         return ret;
1063 }
1064
1065 int consumer_send_channel_monitor_pipe(struct consumer_socket *consumer_sock,
1066                 int pipe)
1067 {
1068         int ret;
1069         struct lttcomm_consumer_msg msg;
1070
1071         /* Code flow error. Safety net. */
1072
1073         memset(&msg, 0, sizeof(msg));
1074         msg.cmd_type = LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE;
1075
1076         pthread_mutex_lock(consumer_sock->lock);
1077         DBG3("Sending set_channel_monitor_pipe command to consumer");
1078         ret = consumer_send_msg(consumer_sock, &msg);
1079         if (ret < 0) {
1080                 goto error;
1081         }
1082
1083         DBG3("Sending channel monitoring pipe %d to consumer on socket %d",
1084                         pipe, *consumer_sock->fd_ptr);
1085         ret = consumer_send_fds(consumer_sock, &pipe, 1);
1086         if (ret < 0) {
1087                 goto error;
1088         }
1089
1090         DBG2("Channel monitoring pipe successfully sent");
1091 error:
1092         pthread_mutex_unlock(consumer_sock->lock);
1093         return ret;
1094 }
1095
1096 /*
1097  * Set consumer subdirectory using the session name and a generated datetime if
1098  * needed. This is appended to the current subdirectory.
1099  */
1100 int consumer_set_subdir(struct consumer_output *consumer,
1101                 const char *session_name)
1102 {
1103         int ret = 0;
1104         unsigned int have_default_name = 0;
1105         char datetime[16], tmp_path[PATH_MAX];
1106         time_t rawtime;
1107         struct tm *timeinfo;
1108
1109         assert(consumer);
1110         assert(session_name);
1111
1112         memset(tmp_path, 0, sizeof(tmp_path));
1113
1114         /* Flag if we have a default session. */
1115         if (strncmp(session_name, DEFAULT_SESSION_NAME "-",
1116                                 strlen(DEFAULT_SESSION_NAME) + 1) == 0) {
1117                 have_default_name = 1;
1118         } else {
1119                 /* Get date and time for session path */
1120                 time(&rawtime);
1121                 timeinfo = localtime(&rawtime);
1122                 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
1123         }
1124
1125         if (have_default_name) {
1126                 ret = snprintf(tmp_path, sizeof(tmp_path),
1127                                 "%s/%s", consumer->subdir, session_name);
1128         } else {
1129                 ret = snprintf(tmp_path, sizeof(tmp_path),
1130                                 "%s/%s-%s/", consumer->subdir, session_name, datetime);
1131         }
1132         if (ret < 0) {
1133                 PERROR("snprintf session name date");
1134                 goto error;
1135         }
1136
1137         if (lttng_strncpy(consumer->subdir, tmp_path,
1138                         sizeof(consumer->subdir))) {
1139                 ret = -EINVAL;
1140                 goto error;
1141         }
1142         DBG2("Consumer subdir set to %s", consumer->subdir);
1143
1144 error:
1145         return ret;
1146 }
1147
1148 /*
1149  * Ask the consumer if the data is pending for the specific session id.
1150  * Returns 1 if data is pending, 0 otherwise, or < 0 on error.
1151  */
1152 int consumer_is_data_pending(uint64_t session_id,
1153                 struct consumer_output *consumer)
1154 {
1155         int ret;
1156         int32_t ret_code = 0;  /* Default is that the data is NOT pending */
1157         struct consumer_socket *socket;
1158         struct lttng_ht_iter iter;
1159         struct lttcomm_consumer_msg msg;
1160
1161         assert(consumer);
1162
1163         DBG3("Consumer data pending for id %" PRIu64, session_id);
1164
1165         memset(&msg, 0, sizeof(msg));
1166         msg.cmd_type = LTTNG_CONSUMER_DATA_PENDING;
1167         msg.u.data_pending.session_id = session_id;
1168
1169         /* Send command for each consumer */
1170         rcu_read_lock();
1171         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1172                         node.node) {
1173                 pthread_mutex_lock(socket->lock);
1174                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1175                 if (ret < 0) {
1176                         pthread_mutex_unlock(socket->lock);
1177                         goto error_unlock;
1178                 }
1179
1180                 /*
1181                  * No need for a recv reply status because the answer to the command is
1182                  * the reply status message.
1183                  */
1184
1185                 ret = consumer_socket_recv(socket, &ret_code, sizeof(ret_code));
1186                 if (ret < 0) {
1187                         pthread_mutex_unlock(socket->lock);
1188                         goto error_unlock;
1189                 }
1190                 pthread_mutex_unlock(socket->lock);
1191
1192                 if (ret_code == 1) {
1193                         break;
1194                 }
1195         }
1196         rcu_read_unlock();
1197
1198         DBG("Consumer data is %s pending for session id %" PRIu64,
1199                         ret_code == 1 ? "" : "NOT", session_id);
1200         return ret_code;
1201
1202 error_unlock:
1203         rcu_read_unlock();
1204         return -1;
1205 }
1206
1207 /*
1208  * Send a flush command to consumer using the given channel key.
1209  *
1210  * Return 0 on success else a negative value.
1211  */
1212 int consumer_flush_channel(struct consumer_socket *socket, uint64_t key)
1213 {
1214         int ret;
1215         struct lttcomm_consumer_msg msg;
1216
1217         assert(socket);
1218
1219         DBG2("Consumer flush channel key %" PRIu64, key);
1220
1221         memset(&msg, 0, sizeof(msg));
1222         msg.cmd_type = LTTNG_CONSUMER_FLUSH_CHANNEL;
1223         msg.u.flush_channel.key = key;
1224
1225         pthread_mutex_lock(socket->lock);
1226         health_code_update();
1227
1228         ret = consumer_send_msg(socket, &msg);
1229         if (ret < 0) {
1230                 goto end;
1231         }
1232
1233 end:
1234         health_code_update();
1235         pthread_mutex_unlock(socket->lock);
1236         return ret;
1237 }
1238
1239 /*
1240  * Send a clear quiescent command to consumer using the given channel key.
1241  *
1242  * Return 0 on success else a negative value.
1243  */
1244 int consumer_clear_quiescent_channel(struct consumer_socket *socket, uint64_t key)
1245 {
1246         int ret;
1247         struct lttcomm_consumer_msg msg;
1248
1249         assert(socket);
1250
1251         DBG2("Consumer clear quiescent channel key %" PRIu64, key);
1252
1253         memset(&msg, 0, sizeof(msg));
1254         msg.cmd_type = LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL;
1255         msg.u.clear_quiescent_channel.key = key;
1256
1257         pthread_mutex_lock(socket->lock);
1258         health_code_update();
1259
1260         ret = consumer_send_msg(socket, &msg);
1261         if (ret < 0) {
1262                 goto end;
1263         }
1264
1265 end:
1266         health_code_update();
1267         pthread_mutex_unlock(socket->lock);
1268         return ret;
1269 }
1270
1271 /*
1272  * Send a close metadata command to consumer using the given channel key.
1273  * Called with registry lock held.
1274  *
1275  * Return 0 on success else a negative value.
1276  */
1277 int consumer_close_metadata(struct consumer_socket *socket,
1278                 uint64_t metadata_key)
1279 {
1280         int ret;
1281         struct lttcomm_consumer_msg msg;
1282
1283         assert(socket);
1284
1285         DBG2("Consumer close metadata channel key %" PRIu64, metadata_key);
1286
1287         memset(&msg, 0, sizeof(msg));
1288         msg.cmd_type = LTTNG_CONSUMER_CLOSE_METADATA;
1289         msg.u.close_metadata.key = metadata_key;
1290
1291         pthread_mutex_lock(socket->lock);
1292         health_code_update();
1293
1294         ret = consumer_send_msg(socket, &msg);
1295         if (ret < 0) {
1296                 goto end;
1297         }
1298
1299 end:
1300         health_code_update();
1301         pthread_mutex_unlock(socket->lock);
1302         return ret;
1303 }
1304
1305 /*
1306  * Send a setup metdata command to consumer using the given channel key.
1307  *
1308  * Return 0 on success else a negative value.
1309  */
1310 int consumer_setup_metadata(struct consumer_socket *socket,
1311                 uint64_t metadata_key)
1312 {
1313         int ret;
1314         struct lttcomm_consumer_msg msg;
1315
1316         assert(socket);
1317
1318         DBG2("Consumer setup metadata channel key %" PRIu64, metadata_key);
1319
1320         memset(&msg, 0, sizeof(msg));
1321         msg.cmd_type = LTTNG_CONSUMER_SETUP_METADATA;
1322         msg.u.setup_metadata.key = metadata_key;
1323
1324         pthread_mutex_lock(socket->lock);
1325         health_code_update();
1326
1327         ret = consumer_send_msg(socket, &msg);
1328         if (ret < 0) {
1329                 goto end;
1330         }
1331
1332 end:
1333         health_code_update();
1334         pthread_mutex_unlock(socket->lock);
1335         return ret;
1336 }
1337
1338 /*
1339  * Send metadata string to consumer.
1340  * RCU read-side lock must be held to guarantee existence of socket.
1341  *
1342  * Return 0 on success else a negative value.
1343  */
1344 int consumer_push_metadata(struct consumer_socket *socket,
1345                 uint64_t metadata_key, char *metadata_str, size_t len,
1346                 size_t target_offset, uint64_t version)
1347 {
1348         int ret;
1349         struct lttcomm_consumer_msg msg;
1350
1351         assert(socket);
1352
1353         DBG2("Consumer push metadata to consumer socket %d", *socket->fd_ptr);
1354
1355         pthread_mutex_lock(socket->lock);
1356
1357         memset(&msg, 0, sizeof(msg));
1358         msg.cmd_type = LTTNG_CONSUMER_PUSH_METADATA;
1359         msg.u.push_metadata.key = metadata_key;
1360         msg.u.push_metadata.target_offset = target_offset;
1361         msg.u.push_metadata.len = len;
1362         msg.u.push_metadata.version = version;
1363
1364         health_code_update();
1365         ret = consumer_send_msg(socket, &msg);
1366         if (ret < 0 || len == 0) {
1367                 goto end;
1368         }
1369
1370         DBG3("Consumer pushing metadata on sock %d of len %zu", *socket->fd_ptr,
1371                         len);
1372
1373         ret = consumer_socket_send(socket, metadata_str, len);
1374         if (ret < 0) {
1375                 goto end;
1376         }
1377
1378         health_code_update();
1379         ret = consumer_recv_status_reply(socket);
1380         if (ret < 0) {
1381                 goto end;
1382         }
1383
1384 end:
1385         pthread_mutex_unlock(socket->lock);
1386         health_code_update();
1387         return ret;
1388 }
1389
1390 /*
1391  * Ask the consumer to snapshot a specific channel using the key.
1392  *
1393  * Return 0 on success or else a negative error.
1394  */
1395 int consumer_snapshot_channel(struct consumer_socket *socket, uint64_t key,
1396                 struct snapshot_output *output, int metadata, uid_t uid, gid_t gid,
1397                 const char *session_path, int wait, uint64_t nb_packets_per_stream)
1398 {
1399         int ret;
1400         struct lttcomm_consumer_msg msg;
1401
1402         assert(socket);
1403         assert(output);
1404         assert(output->consumer);
1405
1406         DBG("Consumer snapshot channel key %" PRIu64, key);
1407
1408         memset(&msg, 0, sizeof(msg));
1409         msg.cmd_type = LTTNG_CONSUMER_SNAPSHOT_CHANNEL;
1410         msg.u.snapshot_channel.key = key;
1411         msg.u.snapshot_channel.nb_packets_per_stream = nb_packets_per_stream;
1412         msg.u.snapshot_channel.metadata = metadata;
1413
1414         if (output->consumer->type == CONSUMER_DST_NET) {
1415                 msg.u.snapshot_channel.relayd_id = output->consumer->net_seq_index;
1416                 msg.u.snapshot_channel.use_relayd = 1;
1417                 ret = snprintf(msg.u.snapshot_channel.pathname,
1418                                 sizeof(msg.u.snapshot_channel.pathname),
1419                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->subdir,
1420                                 output->name, output->datetime, output->nb_snapshot,
1421                                 session_path);
1422                 if (ret < 0) {
1423                         ret = -LTTNG_ERR_NOMEM;
1424                         goto error;
1425                 }
1426         } else {
1427                 ret = snprintf(msg.u.snapshot_channel.pathname,
1428                                 sizeof(msg.u.snapshot_channel.pathname),
1429                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->dst.trace_path,
1430                                 output->name, output->datetime, output->nb_snapshot,
1431                                 session_path);
1432                 if (ret < 0) {
1433                         ret = -LTTNG_ERR_NOMEM;
1434                         goto error;
1435                 }
1436                 msg.u.snapshot_channel.relayd_id = (uint64_t) -1ULL;
1437
1438                 /* Create directory. Ignore if exist. */
1439                 ret = run_as_mkdir_recursive(msg.u.snapshot_channel.pathname,
1440                                 S_IRWXU | S_IRWXG, uid, gid);
1441                 if (ret < 0) {
1442                         if (errno != EEXIST) {
1443                                 ERR("Trace directory creation error");
1444                                 goto error;
1445                         }
1446                 }
1447         }
1448
1449         health_code_update();
1450         pthread_mutex_lock(socket->lock);
1451         ret = consumer_send_msg(socket, &msg);
1452         pthread_mutex_unlock(socket->lock);
1453         if (ret < 0) {
1454                 goto error;
1455         }
1456
1457 error:
1458         health_code_update();
1459         return ret;
1460 }
1461
1462 /*
1463  * Ask the consumer the number of discarded events for a channel.
1464  */
1465 int consumer_get_discarded_events(uint64_t session_id, uint64_t channel_key,
1466                 struct consumer_output *consumer, uint64_t *discarded)
1467 {
1468         int ret;
1469         struct consumer_socket *socket;
1470         struct lttng_ht_iter iter;
1471         struct lttcomm_consumer_msg msg;
1472
1473         assert(consumer);
1474
1475         DBG3("Consumer discarded events id %" PRIu64, session_id);
1476
1477         memset(&msg, 0, sizeof(msg));
1478         msg.cmd_type = LTTNG_CONSUMER_DISCARDED_EVENTS;
1479         msg.u.discarded_events.session_id = session_id;
1480         msg.u.discarded_events.channel_key = channel_key;
1481
1482         *discarded = 0;
1483
1484         /* Send command for each consumer */
1485         rcu_read_lock();
1486         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1487                         node.node) {
1488                 uint64_t consumer_discarded = 0;
1489                 pthread_mutex_lock(socket->lock);
1490                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1491                 if (ret < 0) {
1492                         pthread_mutex_unlock(socket->lock);
1493                         goto end;
1494                 }
1495
1496                 /*
1497                  * No need for a recv reply status because the answer to the
1498                  * command is the reply status message.
1499                  */
1500                 ret = consumer_socket_recv(socket, &consumer_discarded,
1501                                 sizeof(consumer_discarded));
1502                 if (ret < 0) {
1503                         ERR("get discarded events");
1504                         pthread_mutex_unlock(socket->lock);
1505                         goto end;
1506                 }
1507                 pthread_mutex_unlock(socket->lock);
1508                 *discarded += consumer_discarded;
1509         }
1510         ret = 0;
1511         DBG("Consumer discarded %" PRIu64 " events in session id %" PRIu64,
1512                         *discarded, session_id);
1513
1514 end:
1515         rcu_read_unlock();
1516         return ret;
1517 }
1518
1519 /*
1520  * Ask the consumer the number of lost packets for a channel.
1521  */
1522 int consumer_get_lost_packets(uint64_t session_id, uint64_t channel_key,
1523                 struct consumer_output *consumer, uint64_t *lost)
1524 {
1525         int ret;
1526         struct consumer_socket *socket;
1527         struct lttng_ht_iter iter;
1528         struct lttcomm_consumer_msg msg;
1529
1530         assert(consumer);
1531
1532         DBG3("Consumer lost packets id %" PRIu64, session_id);
1533
1534         memset(&msg, 0, sizeof(msg));
1535         msg.cmd_type = LTTNG_CONSUMER_LOST_PACKETS;
1536         msg.u.lost_packets.session_id = session_id;
1537         msg.u.lost_packets.channel_key = channel_key;
1538
1539         *lost = 0;
1540
1541         /* Send command for each consumer */
1542         rcu_read_lock();
1543         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1544                         node.node) {
1545                 uint64_t consumer_lost = 0;
1546                 pthread_mutex_lock(socket->lock);
1547                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1548                 if (ret < 0) {
1549                         pthread_mutex_unlock(socket->lock);
1550                         goto end;
1551                 }
1552
1553                 /*
1554                  * No need for a recv reply status because the answer to the
1555                  * command is the reply status message.
1556                  */
1557                 ret = consumer_socket_recv(socket, &consumer_lost,
1558                                 sizeof(consumer_lost));
1559                 if (ret < 0) {
1560                         ERR("get lost packets");
1561                         pthread_mutex_unlock(socket->lock);
1562                         goto end;
1563                 }
1564                 pthread_mutex_unlock(socket->lock);
1565                 *lost += consumer_lost;
1566         }
1567         ret = 0;
1568         DBG("Consumer lost %" PRIu64 " packets in session id %" PRIu64,
1569                         *lost, session_id);
1570
1571 end:
1572         rcu_read_unlock();
1573         return ret;
1574 }
1575
1576 int consumer_clear_channel(struct consumer_socket *socket, uint64_t key,
1577                 struct consumer_output *output)
1578 {
1579         int ret;
1580         struct lttcomm_consumer_msg msg;
1581
1582         assert(socket);
1583
1584         DBG("Consumer clear channel %" PRIu64, key);
1585
1586         memset(&msg, 0, sizeof(msg));
1587         msg.cmd_type = LTTNG_CONSUMER_CLEAR_CHANNEL;
1588         msg.u.clear_channel.key = key;
1589
1590         health_code_update();
1591
1592         pthread_mutex_lock(socket->lock);
1593         ret = consumer_send_msg(socket, &msg);
1594         if (ret < 0) {
1595                 goto error_socket;
1596         }
1597
1598 error_socket:
1599         pthread_mutex_unlock(socket->lock);
1600
1601         health_code_update();
1602         return ret;
1603 }
1604
1605 static
1606 int consumer_msg_clear_session(struct consumer_socket *socket, uint64_t session_id,
1607                 struct consumer_output *output)
1608 {
1609         int ret;
1610         struct lttcomm_consumer_msg msg;
1611
1612         assert(socket);
1613
1614         DBG("Consumer clear session %" PRIu64, session_id);
1615
1616         memset(&msg, 0, sizeof(msg));
1617         msg.cmd_type = LTTNG_CONSUMER_CLEAR_SESSION;
1618         msg.u.clear_session.session_id = session_id;
1619
1620         health_code_update();
1621
1622         pthread_mutex_lock(socket->lock);
1623         ret = consumer_send_msg(socket, &msg);
1624         if (ret < 0) {
1625                 goto error_socket;
1626         }
1627
1628 error_socket:
1629         pthread_mutex_unlock(socket->lock);
1630
1631         health_code_update();
1632         return ret;
1633 }
1634
1635 int consumer_clear_session(struct ltt_session *session)
1636 {
1637         struct ltt_ust_session *usess = session->ust_session;
1638         struct ltt_kernel_session *ksess = session->kernel_session;
1639         int ret;
1640
1641         rcu_read_lock();
1642         if (ksess) {
1643                 struct consumer_socket *socket;
1644                 struct lttng_ht_iter iter;
1645
1646                 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1647                                 socket, node.node) {
1648                         ret = consumer_msg_clear_session(socket, session->id,
1649                                         ksess->consumer);
1650                         if (ret < 0) {
1651                                 goto error;
1652                         }
1653                 }
1654         }
1655         if (usess) {
1656                 struct consumer_socket *socket;
1657                 struct lttng_ht_iter iter;
1658
1659                 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1660                                 socket, node.node) {
1661                         ret = consumer_msg_clear_session(socket, session->id,
1662                                         usess->consumer);
1663                         if (ret < 0) {
1664                                 goto error;
1665                         }
1666                 }
1667         }
1668         rcu_read_unlock();
1669         return 0;
1670 error:
1671         rcu_read_unlock();
1672         return ret;
1673 }