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 _GNU_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
  32 #include "consumer.h"
  33 #include "health.h"
  34 #include "ust-app.h"
  35 #include "utils.h"
  36
  37 /*
  38  * Send a data payload using a given consumer socket of size len.
  39  *
  40  * The consumer socket lock MUST be acquired before calling this since this
  41  * function can change the fd value.
  42  *
  43  * Return 0 on success else a negative value on error.
  44  */
  45 int consumer_socket_send(struct consumer_socket *socket, void *msg, size_t len)
  46 {
  47         int fd;
  48         ssize_t size;
  49
  50         assert(socket);
  51         assert(socket->fd_ptr);
  52         assert(msg);
  53
  54         /* Consumer socket is invalid. Stopping. */
  55         fd = *socket->fd_ptr;
  56         if (fd < 0) {
  57                 goto error;
  58         }
  59
  60         size = lttcomm_send_unix_sock(fd, msg, len);
  61         if (size < 0) {
  62                 /* The above call will print a PERROR on error. */
  63                 DBG("Error when sending data to consumer on sock %d", fd);
  64                 /*
  65                  * At this point, the socket is not usable anymore thus flagging it
  66                  * invalid and closing it.
  67                  */
  68
  69                 /* This call will PERROR on error. */
  70                 (void) lttcomm_close_unix_sock(fd);
  71                 *socket->fd_ptr = -1;
  72                 goto error;
  73         }
  74
  75         return 0;
  76
  77 error:
  78         return -1;
  79 }
  80
  81 /*
  82  * Receive a data payload using a given consumer socket of size len.
  83  *
  84  * The consumer socket lock MUST be acquired before calling this since this
  85  * function can change the fd value.
  86  *
  87  * Return 0 on success else a negative value on error.
  88  */
  89 int consumer_socket_recv(struct consumer_socket *socket, void *msg, size_t len)
  90 {
  91         int fd;
  92         ssize_t size;
  93
  94         assert(socket);
  95         assert(socket->fd_ptr);
  96         assert(msg);
  97
  98         /* Consumer socket is invalid. Stopping. */
  99         fd = *socket->fd_ptr;
 100         if (fd < 0) {
 101                 goto error;
 102         }
 103
 104         size = lttcomm_recv_unix_sock(fd, msg, len);
 105         if (size <= 0) {
 106                 /* The above call will print a PERROR on error. */
 107                 DBG("Error when receiving data from the consumer socket %d", fd);
 108                 /*
 109                  * At this point, the socket is not usable anymore thus flagging it
 110                  * invalid and closing it.
 111                  */
 112
 113                 /* This call will PERROR on error. */
 114                 (void) lttcomm_close_unix_sock(fd);
 115                 *socket->fd_ptr = -1;
 116                 goto error;
 117         }
 118
 119         return 0;
 120
 121 error:
 122         return -1;
 123 }
 124
 125 /*
 126  * Receive a reply command status message from the consumer. Consumer socket
 127  * lock MUST be acquired before calling this function.
 128  *
 129  * Return 0 on success, -1 on recv error or a negative lttng error code which
 130  * was possibly returned by the consumer.
 131  */
 132 int consumer_recv_status_reply(struct consumer_socket *sock)
 133 {
 134         int ret;
 135         struct lttcomm_consumer_status_msg reply;
 136
 137         assert(sock);
 138
 139         ret = consumer_socket_recv(sock, &reply, sizeof(reply));
 140         if (ret < 0) {
 141                 goto end;
 142         }
 143
 144         if (reply.ret_code == LTTNG_OK) {
 145                 /* All good. */
 146                 ret = 0;
 147         } else {
 148                 ret = -reply.ret_code;
 149                 DBG("Consumer ret code %d", ret);
 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 != LTTNG_OK) {
 181                 ret = -1;
 182                 goto end;
 183         }
 184
 185         *key = reply.key;
 186         *stream_count = reply.stream_count;
 187
 188 end:
 189         return ret;
 190 }
 191
 192 /*
 193  * Send destroy relayd command to consumer.
 194  *
 195  * On success return positive value. On error, negative value.
 196  */
 197 int consumer_send_destroy_relayd(struct consumer_socket *sock,
 198                 struct consumer_output *consumer)
 199 {
 200         int ret;
 201         struct lttcomm_consumer_msg msg;
 202
 203         assert(consumer);
 204         assert(sock);
 205
 206         DBG2("Sending destroy relayd command to consumer sock %d", *sock->fd_ptr);
 207
 208         msg.cmd_type = LTTNG_CONSUMER_DESTROY_RELAYD;
 209         msg.u.destroy_relayd.net_seq_idx = consumer->net_seq_index;
 210
 211         pthread_mutex_lock(sock->lock);
 212         ret = consumer_socket_send(sock, &msg, sizeof(msg));
 213         if (ret < 0) {
 214                 goto error;
 215         }
 216
 217         /* Don't check the return value. The caller will do it. */
 218         ret = consumer_recv_status_reply(sock);
 219
 220         DBG2("Consumer send destroy relayd command done");
 221
 222 error:
 223         pthread_mutex_unlock(sock->lock);
 224         return ret;
 225 }
 226
 227 /*
 228  * For each consumer socket in the consumer output object, send a destroy
 229  * relayd command.
 230  */
 231 void consumer_output_send_destroy_relayd(struct consumer_output *consumer)
 232 {
 233         struct lttng_ht_iter iter;
 234         struct consumer_socket *socket;
 235
 236         assert(consumer);
 237
 238         /* Destroy any relayd connection */
 239         if (consumer->type == CONSUMER_DST_NET) {
 240                 rcu_read_lock();
 241                 cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
 242                                 node.node) {
 243                         int ret;
 244
 245                         /* Send destroy relayd command */
 246                         ret = consumer_send_destroy_relayd(socket, consumer);
 247                         if (ret < 0) {
 248                                 DBG("Unable to send destroy relayd command to consumer");
 249                                 /* Continue since we MUST delete everything at this point. */
 250                         }
 251                 }
 252                 rcu_read_unlock();
 253         }
 254 }
 255
 256 /*
 257  * From a consumer_data structure, allocate and add a consumer socket to the
 258  * consumer output.
 259  *
 260  * Return 0 on success, else negative value on error
 261  */
 262 int consumer_create_socket(struct consumer_data *data,
 263                 struct consumer_output *output)
 264 {
 265         int ret = 0;
 266         struct consumer_socket *socket;
 267
 268         assert(data);
 269
 270         if (output == NULL || data->cmd_sock < 0) {
 271                 /*
 272                  * Not an error. Possible there is simply not spawned consumer or it's
 273                  * disabled for the tracing session asking the socket.
 274                  */
 275                 goto error;
 276         }
 277
 278         rcu_read_lock();
 279         socket = consumer_find_socket(data->cmd_sock, output);
 280         rcu_read_unlock();
 281         if (socket == NULL) {
 282                 socket = consumer_allocate_socket(&data->cmd_sock);
 283                 if (socket == NULL) {
 284                         ret = -1;
 285                         goto error;
 286                 }
 287
 288                 socket->registered = 0;
 289                 socket->lock = &data->lock;
 290                 rcu_read_lock();
 291                 consumer_add_socket(socket, output);
 292                 rcu_read_unlock();
 293         }
 294
 295         socket->type = data->type;
 296
 297         DBG3("Consumer socket created (fd: %d) and added to output",
 298                         data->cmd_sock);
 299
 300 error:
 301         return ret;
 302 }
 303
 304 /*
 305  * Return the consumer socket from the given consumer output with the right
 306  * bitness. On error, returns NULL.
 307  *
 308  * The caller MUST acquire a rcu read side lock and keep it until the socket
 309  * object reference is not needed anymore.
 310  */
 311 struct consumer_socket *consumer_find_socket_by_bitness(int bits,
 312                 struct consumer_output *consumer)
 313 {
 314         int consumer_fd;
 315         struct consumer_socket *socket = NULL;
 316
 317         switch (bits) {
 318         case 64:
 319                 consumer_fd = uatomic_read(&ust_consumerd64_fd);
 320                 break;
 321         case 32:
 322                 consumer_fd = uatomic_read(&ust_consumerd32_fd);
 323                 break;
 324         default:
 325                 assert(0);
 326                 goto end;
 327         }
 328
 329         socket = consumer_find_socket(consumer_fd, consumer);
 330         if (!socket) {
 331                 ERR("Consumer socket fd %d not found in consumer obj %p",
 332                                 consumer_fd, consumer);
 333         }
 334
 335 end:
 336         return socket;
 337 }
 338
 339 /*
 340  * Find a consumer_socket in a consumer_output hashtable. Read side lock must
 341  * be acquired before calling this function and across use of the
 342  * returned consumer_socket.
 343  */
 344 struct consumer_socket *consumer_find_socket(int key,
 345                 struct consumer_output *consumer)
 346 {
 347         struct lttng_ht_iter iter;
 348         struct lttng_ht_node_ulong *node;
 349         struct consumer_socket *socket = NULL;
 350
 351         /* Negative keys are lookup failures */
 352         if (key < 0 || consumer == NULL) {
 353                 return NULL;
 354         }
 355
 356         lttng_ht_lookup(consumer->socks, (void *)((unsigned long) key),
 357                         &iter);
 358         node = lttng_ht_iter_get_node_ulong(&iter);
 359         if (node != NULL) {
 360                 socket = caa_container_of(node, struct consumer_socket, node);
 361         }
 362
 363         return socket;
 364 }
 365
 366 /*
 367  * Allocate a new consumer_socket and return the pointer.
 368  */
 369 struct consumer_socket *consumer_allocate_socket(int *fd)
 370 {
 371         struct consumer_socket *socket = NULL;
 372
 373         assert(fd);
 374
 375         socket = zmalloc(sizeof(struct consumer_socket));
 376         if (socket == NULL) {
 377                 PERROR("zmalloc consumer socket");
 378                 goto error;
 379         }
 380
 381         socket->fd_ptr = fd;
 382         lttng_ht_node_init_ulong(&socket->node, *fd);
 383
 384 error:
 385         return socket;
 386 }
 387
 388 /*
 389  * Add consumer socket to consumer output object. Read side lock must be
 390  * acquired before calling this function.
 391  */
 392 void consumer_add_socket(struct consumer_socket *sock,
 393                 struct consumer_output *consumer)
 394 {
 395         assert(sock);
 396         assert(consumer);
 397
 398         lttng_ht_add_unique_ulong(consumer->socks, &sock->node);
 399 }
 400
 401 /*
 402  * Delte consumer socket to consumer output object. Read side lock must be
 403  * acquired before calling this function.
 404  */
 405 void consumer_del_socket(struct consumer_socket *sock,
 406                 struct consumer_output *consumer)
 407 {
 408         int ret;
 409         struct lttng_ht_iter iter;
 410
 411         assert(sock);
 412         assert(consumer);
 413
 414         iter.iter.node = &sock->node.node;
 415         ret = lttng_ht_del(consumer->socks, &iter);
 416         assert(!ret);
 417 }
 418
 419 /*
 420  * RCU destroy call function.
 421  */
 422 static void destroy_socket_rcu(struct rcu_head *head)
 423 {
 424         struct lttng_ht_node_ulong *node =
 425                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 426         struct consumer_socket *socket =
 427                 caa_container_of(node, struct consumer_socket, node);
 428
 429         free(socket);
 430 }
 431
 432 /*
 433  * Destroy and free socket pointer in a call RCU. Read side lock must be
 434  * acquired before calling this function.
 435  */
 436 void consumer_destroy_socket(struct consumer_socket *sock)
 437 {
 438         assert(sock);
 439
 440         /*
 441          * We DO NOT close the file descriptor here since it is global to the
 442          * session daemon and is closed only if the consumer dies or a custom
 443          * consumer was registered,
 444          */
 445         if (sock->registered) {
 446                 DBG3("Consumer socket was registered. Closing fd %d", *sock->fd_ptr);
 447                 lttcomm_close_unix_sock(*sock->fd_ptr);
 448         }
 449
 450         call_rcu(&sock->node.head, destroy_socket_rcu);
 451 }
 452
 453 /*
 454  * Allocate and assign data to a consumer_output object.
 455  *
 456  * Return pointer to structure.
 457  */
 458 struct consumer_output *consumer_create_output(enum consumer_dst_type type)
 459 {
 460         struct consumer_output *output = NULL;
 461
 462         output = zmalloc(sizeof(struct consumer_output));
 463         if (output == NULL) {
 464                 PERROR("zmalloc consumer_output");
 465                 goto error;
 466         }
 467
 468         /* By default, consumer output is enabled */
 469         output->enabled = 1;
 470         output->type = type;
 471         output->net_seq_index = (uint64_t) -1ULL;
 472
 473         output->socks = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 474
 475 error:
 476         return output;
 477 }
 478
 479 /*
 480  * Iterate over the consumer output socket hash table and destroy them. The
 481  * socket file descriptor are only closed if the consumer output was
 482  * registered meaning it's an external consumer.
 483  */
 484 void consumer_destroy_output_sockets(struct consumer_output *obj)
 485 {
 486         struct lttng_ht_iter iter;
 487         struct consumer_socket *socket;
 488
 489         if (!obj->socks) {
 490                 return;
 491         }
 492
 493         rcu_read_lock();
 494         cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 495                 consumer_del_socket(socket, obj);
 496                 consumer_destroy_socket(socket);
 497         }
 498         rcu_read_unlock();
 499 }
 500
 501 /*
 502  * Delete the consumer_output object from the list and free the ptr.
 503  *
 504  * Should *NOT* be called with RCU read-side lock held.
 505  */
 506 void consumer_destroy_output(struct consumer_output *obj)
 507 {
 508         if (obj == NULL) {
 509                 return;
 510         }
 511
 512         consumer_destroy_output_sockets(obj);
 513
 514         if (obj->socks) {
 515                 /* Finally destroy HT */
 516                 ht_cleanup_push(obj->socks);
 517         }
 518
 519         free(obj);
 520 }
 521
 522 /*
 523  * Copy consumer output and returned the newly allocated copy.
 524  *
 525  * Should *NOT* be called with RCU read-side lock held.
 526  */
 527 struct consumer_output *consumer_copy_output(struct consumer_output *obj)
 528 {
 529         int ret;
 530         struct lttng_ht *tmp_ht_ptr;
 531         struct consumer_output *output;
 532
 533         assert(obj);
 534
 535         output = consumer_create_output(obj->type);
 536         if (output == NULL) {
 537                 goto error;
 538         }
 539         /* Avoid losing the HT reference after the memcpy() */
 540         tmp_ht_ptr = output->socks;
 541
 542         memcpy(output, obj, sizeof(struct consumer_output));
 543
 544         /* Putting back the HT pointer and start copying socket(s). */
 545         output->socks = tmp_ht_ptr;
 546
 547         ret = consumer_copy_sockets(output, obj);
 548         if (ret < 0) {
 549                 goto malloc_error;
 550         }
 551
 552 error:
 553         return output;
 554
 555 malloc_error:
 556         consumer_destroy_output(output);
 557         return NULL;
 558 }
 559
 560 /*
 561  * Copy consumer sockets from src to dst.
 562  *
 563  * Return 0 on success or else a negative value.
 564  */
 565 int consumer_copy_sockets(struct consumer_output *dst,
 566                 struct consumer_output *src)
 567 {
 568         int ret = 0;
 569         struct lttng_ht_iter iter;
 570         struct consumer_socket *socket, *copy_sock;
 571
 572         assert(dst);
 573         assert(src);
 574
 575         rcu_read_lock();
 576         cds_lfht_for_each_entry(src->socks->ht, &iter.iter, socket, node.node) {
 577                 /* Ignore socket that are already there. */
 578                 copy_sock = consumer_find_socket(*socket->fd_ptr, dst);
 579                 if (copy_sock) {
 580                         continue;
 581                 }
 582
 583                 /* Create new socket object. */
 584                 copy_sock = consumer_allocate_socket(socket->fd_ptr);
 585                 if (copy_sock == NULL) {
 586                         rcu_read_unlock();
 587                         ret = -ENOMEM;
 588                         goto error;
 589                 }
 590
 591                 copy_sock->registered = socket->registered;
 592                 /*
 593                  * This is valid because this lock is shared accross all consumer
 594                  * object being the global lock of the consumer data structure of the
 595                  * session daemon.
 596                  */
 597                 copy_sock->lock = socket->lock;
 598                 consumer_add_socket(copy_sock, dst);
 599         }
 600         rcu_read_unlock();
 601
 602 error:
 603         return ret;
 604 }
 605
 606 /*
 607  * Set network URI to the consumer output object.
 608  *
 609  * Return 0 on success. Return 1 if the URI were equal. Else, negative value on
 610  * error.
 611  */
 612 int consumer_set_network_uri(struct consumer_output *obj,
 613                 struct lttng_uri *uri)
 614 {
 615         int ret;
 616         char tmp_path[PATH_MAX];
 617         char hostname[HOST_NAME_MAX];
 618         struct lttng_uri *dst_uri = NULL;
 619
 620         /* Code flow error safety net. */
 621         assert(obj);
 622         assert(uri);
 623
 624         switch (uri->stype) {
 625         case LTTNG_STREAM_CONTROL:
 626                 dst_uri = &obj->dst.net.control;
 627                 obj->dst.net.control_isset = 1;
 628                 if (uri->port == 0) {
 629                         /* Assign default port. */
 630                         uri->port = DEFAULT_NETWORK_CONTROL_PORT;
 631                 } else {
 632                         if (obj->dst.net.data_isset && uri->port ==
 633                                         obj->dst.net.data.port) {
 634                                 ret = -LTTNG_ERR_INVALID;
 635                                 goto error;
 636                         }
 637                 }
 638                 DBG3("Consumer control URI set with port %d", uri->port);
 639                 break;
 640         case LTTNG_STREAM_DATA:
 641                 dst_uri = &obj->dst.net.data;
 642                 obj->dst.net.data_isset = 1;
 643                 if (uri->port == 0) {
 644                         /* Assign default port. */
 645                         uri->port = DEFAULT_NETWORK_DATA_PORT;
 646                 } else {
 647                         if (obj->dst.net.control_isset && uri->port ==
 648                                         obj->dst.net.control.port) {
 649                                 ret = -LTTNG_ERR_INVALID;
 650                                 goto error;
 651                         }
 652                 }
 653                 DBG3("Consumer data URI set with port %d", uri->port);
 654                 break;
 655         default:
 656                 ERR("Set network uri type unknown %d", uri->stype);
 657                 ret = -LTTNG_ERR_INVALID;
 658                 goto error;
 659         }
 660
 661         ret = uri_compare(dst_uri, uri);
 662         if (!ret) {
 663                 /* Same URI, don't touch it and return success. */
 664                 DBG3("URI network compare are the same");
 665                 goto equal;
 666         }
 667
 668         /* URIs were not equal, replacing it. */
 669         memset(dst_uri, 0, sizeof(struct lttng_uri));
 670         memcpy(dst_uri, uri, sizeof(struct lttng_uri));
 671         obj->type = CONSUMER_DST_NET;
 672
 673         /* Handle subdir and add hostname in front. */
 674         if (dst_uri->stype == LTTNG_STREAM_CONTROL) {
 675                 /* Get hostname to append it in the pathname */
 676                 ret = gethostname(hostname, sizeof(hostname));
 677                 if (ret < 0) {
 678                         PERROR("gethostname. Fallback on default localhost");
 679                         strncpy(hostname, "localhost", sizeof(hostname));
 680                 }
 681                 hostname[sizeof(hostname) - 1] = '\0';
 682
 683                 /* Setup consumer subdir if none present in the control URI */
 684                 if (strlen(dst_uri->subdir) == 0) {
 685                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 686                                         hostname, obj->subdir);
 687                 } else {
 688                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 689                                         hostname, dst_uri->subdir);
 690                 }
 691                 if (ret < 0) {
 692                         PERROR("snprintf set consumer uri subdir");
 693                         ret = -LTTNG_ERR_NOMEM;
 694                         goto error;
 695                 }
 696
 697                 strncpy(obj->subdir, tmp_path, sizeof(obj->subdir));
 698                 DBG3("Consumer set network uri subdir path %s", tmp_path);
 699         }
 700
 701         return 0;
 702 equal:
 703         return 1;
 704 error:
 705         return ret;
 706 }
 707
 708 /*
 709  * Send file descriptor to consumer via sock.
 710  */
 711 int consumer_send_fds(struct consumer_socket *sock, int *fds, size_t nb_fd)
 712 {
 713         int ret;
 714
 715         assert(fds);
 716         assert(sock);
 717         assert(nb_fd > 0);
 718
 719         ret = lttcomm_send_fds_unix_sock(*sock->fd_ptr, fds, nb_fd);
 720         if (ret < 0) {
 721                 /* The above call will print a PERROR on error. */
 722                 DBG("Error when sending consumer fds on sock %d", *sock->fd_ptr);
 723                 goto error;
 724         }
 725
 726         ret = consumer_recv_status_reply(sock);
 727
 728 error:
 729         return ret;
 730 }
 731
 732 /*
 733  * Consumer send communication message structure to consumer.
 734  */
 735 int consumer_send_msg(struct consumer_socket *sock,
 736                 struct lttcomm_consumer_msg *msg)
 737 {
 738         int ret;
 739
 740         assert(msg);
 741         assert(sock);
 742
 743         ret = consumer_socket_send(sock, msg, sizeof(struct lttcomm_consumer_msg));
 744         if (ret < 0) {
 745                 goto error;
 746         }
 747
 748         ret = consumer_recv_status_reply(sock);
 749
 750 error:
 751         return ret;
 752 }
 753
 754 /*
 755  * Consumer send channel communication message structure to consumer.
 756  */
 757 int consumer_send_channel(struct consumer_socket *sock,
 758                 struct lttcomm_consumer_msg *msg)
 759 {
 760         int ret;
 761
 762         assert(msg);
 763         assert(sock);
 764
 765         ret = consumer_send_msg(sock, msg);
 766         if (ret < 0) {
 767                 goto error;
 768         }
 769
 770 error:
 771         return ret;
 772 }
 773
 774 /*
 775  * Populate the given consumer msg structure with the ask_channel command
 776  * information.
 777  */
 778 void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 779                 uint64_t subbuf_size,
 780                 uint64_t num_subbuf,
 781                 int overwrite,
 782                 unsigned int switch_timer_interval,
 783                 unsigned int read_timer_interval,
 784                 int output,
 785                 int type,
 786                 uint64_t session_id,
 787                 const char *pathname,
 788                 const char *name,
 789                 uid_t uid,
 790                 gid_t gid,
 791                 uint64_t relayd_id,
 792                 uint64_t key,
 793                 unsigned char *uuid,
 794                 uint32_t chan_id,
 795                 uint64_t tracefile_size,
 796                 uint64_t tracefile_count,
 797                 uint64_t session_id_per_pid,
 798                 unsigned int monitor,
 799                 uint32_t ust_app_uid)
 800 {
 801         assert(msg);
 802
 803         /* Zeroed structure */
 804         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 805
 806         msg->cmd_type = LTTNG_CONSUMER_ASK_CHANNEL_CREATION;
 807         msg->u.ask_channel.subbuf_size = subbuf_size;
 808         msg->u.ask_channel.num_subbuf = num_subbuf ;
 809         msg->u.ask_channel.overwrite = overwrite;
 810         msg->u.ask_channel.switch_timer_interval = switch_timer_interval;
 811         msg->u.ask_channel.read_timer_interval = read_timer_interval;
 812         msg->u.ask_channel.output = output;
 813         msg->u.ask_channel.type = type;
 814         msg->u.ask_channel.session_id = session_id;
 815         msg->u.ask_channel.session_id_per_pid = session_id_per_pid;
 816         msg->u.ask_channel.uid = uid;
 817         msg->u.ask_channel.gid = gid;
 818         msg->u.ask_channel.relayd_id = relayd_id;
 819         msg->u.ask_channel.key = key;
 820         msg->u.ask_channel.chan_id = chan_id;
 821         msg->u.ask_channel.tracefile_size = tracefile_size;
 822         msg->u.ask_channel.tracefile_count = tracefile_count;
 823         msg->u.ask_channel.monitor = monitor;
 824         msg->u.ask_channel.ust_app_uid = ust_app_uid;
 825
 826         memcpy(msg->u.ask_channel.uuid, uuid, sizeof(msg->u.ask_channel.uuid));
 827
 828         if (pathname) {
 829                 strncpy(msg->u.ask_channel.pathname, pathname,
 830                                 sizeof(msg->u.ask_channel.pathname));
 831                 msg->u.ask_channel.pathname[sizeof(msg->u.ask_channel.pathname)-1] = '\0';
 832         }
 833
 834         strncpy(msg->u.ask_channel.name, name, sizeof(msg->u.ask_channel.name));
 835         msg->u.ask_channel.name[sizeof(msg->u.ask_channel.name) - 1] = '\0';
 836 }
 837
 838 /*
 839  * Init channel communication message structure.
 840  */
 841 void consumer_init_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 842                 enum lttng_consumer_command cmd,
 843                 uint64_t channel_key,
 844                 uint64_t session_id,
 845                 const char *pathname,
 846                 uid_t uid,
 847                 gid_t gid,
 848                 uint64_t relayd_id,
 849                 const char *name,
 850                 unsigned int nb_init_streams,
 851                 enum lttng_event_output output,
 852                 int type,
 853                 uint64_t tracefile_size,
 854                 uint64_t tracefile_count,
 855                 unsigned int monitor)
 856 {
 857         assert(msg);
 858
 859         /* Zeroed structure */
 860         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 861
 862         /* Send channel */
 863         msg->cmd_type = cmd;
 864         msg->u.channel.channel_key = channel_key;
 865         msg->u.channel.session_id = session_id;
 866         msg->u.channel.uid = uid;
 867         msg->u.channel.gid = gid;
 868         msg->u.channel.relayd_id = relayd_id;
 869         msg->u.channel.nb_init_streams = nb_init_streams;
 870         msg->u.channel.output = output;
 871         msg->u.channel.type = type;
 872         msg->u.channel.tracefile_size = tracefile_size;
 873         msg->u.channel.tracefile_count = tracefile_count;
 874         msg->u.channel.monitor = monitor;
 875
 876         strncpy(msg->u.channel.pathname, pathname,
 877                         sizeof(msg->u.channel.pathname));
 878         msg->u.channel.pathname[sizeof(msg->u.channel.pathname) - 1] = '\0';
 879
 880         strncpy(msg->u.channel.name, name, sizeof(msg->u.channel.name));
 881         msg->u.channel.name[sizeof(msg->u.channel.name) - 1] = '\0';
 882 }
 883
 884 /*
 885  * Init stream communication message structure.
 886  */
 887 void consumer_init_stream_comm_msg(struct lttcomm_consumer_msg *msg,
 888                 enum lttng_consumer_command cmd,
 889                 uint64_t channel_key,
 890                 uint64_t stream_key,
 891                 int cpu)
 892 {
 893         assert(msg);
 894
 895         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 896
 897         msg->cmd_type = cmd;
 898         msg->u.stream.channel_key = channel_key;
 899         msg->u.stream.stream_key = stream_key;
 900         msg->u.stream.cpu = cpu;
 901 }
 902
 903 /*
 904  * Send stream communication structure to the consumer.
 905  */
 906 int consumer_send_stream(struct consumer_socket *sock,
 907                 struct consumer_output *dst, struct lttcomm_consumer_msg *msg,
 908                 int *fds, size_t nb_fd)
 909 {
 910         int ret;
 911
 912         assert(msg);
 913         assert(dst);
 914         assert(sock);
 915         assert(fds);
 916
 917         ret = consumer_send_msg(sock, msg);
 918         if (ret < 0) {
 919                 goto error;
 920         }
 921
 922         ret = consumer_send_fds(sock, fds, nb_fd);
 923         if (ret < 0) {
 924                 goto error;
 925         }
 926
 927 error:
 928         return ret;
 929 }
 930
 931 /*
 932  * Send relayd socket to consumer associated with a session name.
 933  *
 934  * On success return positive value. On error, negative value.
 935  */
 936 int consumer_send_relayd_socket(struct consumer_socket *consumer_sock,
 937                 struct lttcomm_relayd_sock *rsock, struct consumer_output *consumer,
 938                 enum lttng_stream_type type, uint64_t session_id)
 939 {
 940         int ret;
 941         struct lttcomm_consumer_msg msg;
 942
 943         /* Code flow error. Safety net. */
 944         assert(rsock);
 945         assert(consumer);
 946         assert(consumer_sock);
 947
 948         /* Bail out if consumer is disabled */
 949         if (!consumer->enabled) {
 950                 ret = LTTNG_OK;
 951                 goto error;
 952         }
 953
 954         msg.cmd_type = LTTNG_CONSUMER_ADD_RELAYD_SOCKET;
 955         /*
 956          * Assign network consumer output index using the temporary consumer since
 957          * this call should only be made from within a set_consumer_uri() function
 958          * call in the session daemon.
 959          */
 960         msg.u.relayd_sock.net_index = consumer->net_seq_index;
 961         msg.u.relayd_sock.type = type;
 962         msg.u.relayd_sock.session_id = session_id;
 963         memcpy(&msg.u.relayd_sock.sock, rsock, sizeof(msg.u.relayd_sock.sock));
 964
 965         DBG3("Sending relayd sock info to consumer on %d", *consumer_sock->fd_ptr);
 966         ret = consumer_send_msg(consumer_sock, &msg);
 967         if (ret < 0) {
 968                 goto error;
 969         }
 970
 971         DBG3("Sending relayd socket file descriptor to consumer");
 972         ret = consumer_send_fds(consumer_sock, &rsock->sock.fd, 1);
 973         if (ret < 0) {
 974                 goto error;
 975         }
 976
 977         DBG2("Consumer relayd socket sent");
 978
 979 error:
 980         return ret;
 981 }
 982
 983 /*
 984  * Set consumer subdirectory using the session name and a generated datetime if
 985  * needed. This is appended to the current subdirectory.
 986  */
 987 int consumer_set_subdir(struct consumer_output *consumer,
 988                 const char *session_name)
 989 {
 990         int ret = 0;
 991         unsigned int have_default_name = 0;
 992         char datetime[16], tmp_path[PATH_MAX];
 993         time_t rawtime;
 994         struct tm *timeinfo;
 995
 996         assert(consumer);
 997         assert(session_name);
 998
 999         memset(tmp_path, 0, sizeof(tmp_path));
1000
1001         /* Flag if we have a default session. */
1002         if (strncmp(session_name, DEFAULT_SESSION_NAME "-",
1003                                 strlen(DEFAULT_SESSION_NAME) + 1) == 0) {
1004                 have_default_name = 1;
1005         } else {
1006                 /* Get date and time for session path */
1007                 time(&rawtime);
1008                 timeinfo = localtime(&rawtime);
1009                 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
1010         }
1011
1012         if (have_default_name) {
1013                 ret = snprintf(tmp_path, sizeof(tmp_path),
1014                                 "%s/%s", consumer->subdir, session_name);
1015         } else {
1016                 ret = snprintf(tmp_path, sizeof(tmp_path),
1017                                 "%s/%s-%s/", consumer->subdir, session_name, datetime);
1018         }
1019         if (ret < 0) {
1020                 PERROR("snprintf session name date");
1021                 goto error;
1022         }
1023
1024         strncpy(consumer->subdir, tmp_path, sizeof(consumer->subdir));
1025         DBG2("Consumer subdir set to %s", consumer->subdir);
1026
1027 error:
1028         return ret;
1029 }
1030
1031 /*
1032  * Ask the consumer if the data is ready to read (NOT pending) for the specific
1033  * session id.
1034  *
1035  * This function has a different behavior with the consumer i.e. that it waits
1036  * for a reply from the consumer if yes or no the data is pending.
1037  */
1038 int consumer_is_data_pending(uint64_t session_id,
1039                 struct consumer_output *consumer)
1040 {
1041         int ret;
1042         int32_t ret_code = 0;  /* Default is that the data is NOT pending */
1043         struct consumer_socket *socket;
1044         struct lttng_ht_iter iter;
1045         struct lttcomm_consumer_msg msg;
1046
1047         assert(consumer);
1048
1049         msg.cmd_type = LTTNG_CONSUMER_DATA_PENDING;
1050
1051         msg.u.data_pending.session_id = session_id;
1052
1053         DBG3("Consumer data pending for id %" PRIu64, session_id);
1054
1055         /* Send command for each consumer */
1056         rcu_read_lock();
1057         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1058                         node.node) {
1059                 pthread_mutex_lock(socket->lock);
1060                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1061                 if (ret < 0) {
1062                         pthread_mutex_unlock(socket->lock);
1063                         goto error_unlock;
1064                 }
1065
1066                 /*
1067                  * No need for a recv reply status because the answer to the command is
1068                  * the reply status message.
1069                  */
1070
1071                 ret = consumer_socket_recv(socket, &ret_code, sizeof(ret_code));
1072                 if (ret < 0) {
1073                         pthread_mutex_unlock(socket->lock);
1074                         goto error_unlock;
1075                 }
1076                 pthread_mutex_unlock(socket->lock);
1077
1078                 if (ret_code == 1) {
1079                         break;
1080                 }
1081         }
1082         rcu_read_unlock();
1083
1084         DBG("Consumer data is %s pending for session id %" PRIu64,
1085                         ret_code == 1 ? "" : "NOT", session_id);
1086         return ret_code;
1087
1088 error_unlock:
1089         rcu_read_unlock();
1090         return -1;
1091 }
1092
1093 /*
1094  * Send a flush command to consumer using the given channel key.
1095  *
1096  * Return 0 on success else a negative value.
1097  */
1098 int consumer_flush_channel(struct consumer_socket *socket, uint64_t key)
1099 {
1100         int ret;
1101         struct lttcomm_consumer_msg msg;
1102
1103         assert(socket);
1104
1105         DBG2("Consumer flush channel key %" PRIu64, key);
1106
1107         msg.cmd_type = LTTNG_CONSUMER_FLUSH_CHANNEL;
1108         msg.u.flush_channel.key = key;
1109
1110         pthread_mutex_lock(socket->lock);
1111         health_code_update();
1112
1113         ret = consumer_send_msg(socket, &msg);
1114         if (ret < 0) {
1115                 goto end;
1116         }
1117
1118 end:
1119         health_code_update();
1120         pthread_mutex_unlock(socket->lock);
1121         return ret;
1122 }
1123
1124 /*
1125  * Send a close metdata command to consumer using the given channel key.
1126  *
1127  * Return 0 on success else a negative value.
1128  */
1129 int consumer_close_metadata(struct consumer_socket *socket,
1130                 uint64_t metadata_key)
1131 {
1132         int ret;
1133         struct lttcomm_consumer_msg msg;
1134
1135         assert(socket);
1136
1137         DBG2("Consumer close metadata channel key %" PRIu64, metadata_key);
1138
1139         msg.cmd_type = LTTNG_CONSUMER_CLOSE_METADATA;
1140         msg.u.close_metadata.key = metadata_key;
1141
1142         pthread_mutex_lock(socket->lock);
1143         health_code_update();
1144
1145         ret = consumer_send_msg(socket, &msg);
1146         if (ret < 0) {
1147                 goto end;
1148         }
1149
1150 end:
1151         health_code_update();
1152         pthread_mutex_unlock(socket->lock);
1153         return ret;
1154 }
1155
1156 /*
1157  * Send a setup metdata command to consumer using the given channel key.
1158  *
1159  * Return 0 on success else a negative value.
1160  */
1161 int consumer_setup_metadata(struct consumer_socket *socket,
1162                 uint64_t metadata_key)
1163 {
1164         int ret;
1165         struct lttcomm_consumer_msg msg;
1166
1167         assert(socket);
1168
1169         DBG2("Consumer setup metadata channel key %" PRIu64, metadata_key);
1170
1171         msg.cmd_type = LTTNG_CONSUMER_SETUP_METADATA;
1172         msg.u.setup_metadata.key = metadata_key;
1173
1174         pthread_mutex_lock(socket->lock);
1175         health_code_update();
1176
1177         ret = consumer_send_msg(socket, &msg);
1178         if (ret < 0) {
1179                 goto end;
1180         }
1181
1182 end:
1183         health_code_update();
1184         pthread_mutex_unlock(socket->lock);
1185         return ret;
1186 }
1187
1188 /*
1189  * Send metadata string to consumer. Socket lock MUST be acquired.
1190  *
1191  * Return 0 on success else a negative value.
1192  */
1193 int consumer_push_metadata(struct consumer_socket *socket,
1194                 uint64_t metadata_key, char *metadata_str, size_t len,
1195                 size_t target_offset)
1196 {
1197         int ret;
1198         struct lttcomm_consumer_msg msg;
1199
1200         assert(socket);
1201
1202         DBG2("Consumer push metadata to consumer socket %d", *socket->fd_ptr);
1203
1204         msg.cmd_type = LTTNG_CONSUMER_PUSH_METADATA;
1205         msg.u.push_metadata.key = metadata_key;
1206         msg.u.push_metadata.target_offset = target_offset;
1207         msg.u.push_metadata.len = len;
1208
1209         health_code_update();
1210         ret = consumer_send_msg(socket, &msg);
1211         if (ret < 0 || len == 0) {
1212                 goto end;
1213         }
1214
1215         DBG3("Consumer pushing metadata on sock %d of len %zu", *socket->fd_ptr,
1216                         len);
1217
1218         ret = consumer_socket_send(socket, metadata_str, len);
1219         if (ret < 0) {
1220                 goto end;
1221         }
1222
1223         health_code_update();
1224         ret = consumer_recv_status_reply(socket);
1225         if (ret < 0) {
1226                 goto end;
1227         }
1228
1229 end:
1230         health_code_update();
1231         return ret;
1232 }
1233
1234 /*
1235  * Ask the consumer to snapshot a specific channel using the key.
1236  *
1237  * Return 0 on success or else a negative error.
1238  */
1239 int consumer_snapshot_channel(struct consumer_socket *socket, uint64_t key,
1240                 struct snapshot_output *output, int metadata, uid_t uid, gid_t gid,
1241                 const char *session_path, int wait, int max_stream_size)
1242 {
1243         int ret;
1244         struct lttcomm_consumer_msg msg;
1245
1246         assert(socket);
1247         assert(output);
1248         assert(output->consumer);
1249
1250         DBG("Consumer snapshot channel key %" PRIu64, key);
1251
1252         memset(&msg, 0, sizeof(msg));
1253         msg.cmd_type = LTTNG_CONSUMER_SNAPSHOT_CHANNEL;
1254         msg.u.snapshot_channel.key = key;
1255         msg.u.snapshot_channel.max_stream_size = max_stream_size;
1256         msg.u.snapshot_channel.metadata = metadata;
1257
1258         if (output->consumer->type == CONSUMER_DST_NET) {
1259                 msg.u.snapshot_channel.relayd_id = output->consumer->net_seq_index;
1260                 msg.u.snapshot_channel.use_relayd = 1;
1261                 ret = snprintf(msg.u.snapshot_channel.pathname,
1262                                 sizeof(msg.u.snapshot_channel.pathname),
1263                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->subdir,
1264                                 output->name, output->datetime, output->nb_snapshot,
1265                                 session_path);
1266                 if (ret < 0) {
1267                         ret = -LTTNG_ERR_NOMEM;
1268                         goto error;
1269                 }
1270         } else {
1271                 ret = snprintf(msg.u.snapshot_channel.pathname,
1272                                 sizeof(msg.u.snapshot_channel.pathname),
1273                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->dst.trace_path,
1274                                 output->name, output->datetime, output->nb_snapshot,
1275                                 session_path);
1276                 if (ret < 0) {
1277                         ret = -LTTNG_ERR_NOMEM;
1278                         goto error;
1279                 }
1280                 msg.u.snapshot_channel.relayd_id = (uint64_t) -1ULL;
1281
1282                 /* Create directory. Ignore if exist. */
1283                 ret = run_as_mkdir_recursive(msg.u.snapshot_channel.pathname,
1284                                 S_IRWXU | S_IRWXG, uid, gid);
1285                 if (ret < 0) {
1286                         if (ret != -EEXIST) {
1287                                 ERR("Trace directory creation error");
1288                                 goto error;
1289                         }
1290                 }
1291         }
1292
1293         health_code_update();
1294         ret = consumer_send_msg(socket, &msg);
1295         if (ret < 0) {
1296                 goto error;
1297         }
1298
1299 error:
1300         health_code_update();
1301         return ret;
1302 }