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 #include <common/relayd/relayd.h>
  32
  33 #include "consumer.h"
  34 #include "health-sessiond.h"
  35 #include "ust-app.h"
  36 #include "utils.h"
  37
  38 /*
  39  * Send a data payload using a given consumer socket of size len.
  40  *
  41  * The consumer socket lock MUST be acquired before calling this since this
  42  * function can change the fd value.
  43  *
  44  * Return 0 on success else a negative value on error.
  45  */
  46 int consumer_socket_send(struct consumer_socket *socket, void *msg, size_t len)
  47 {
  48         int fd;
  49         ssize_t size;
  50
  51         assert(socket);
  52         assert(socket->fd_ptr);
  53         assert(msg);
  54
  55         /* Consumer socket is invalid. Stopping. */
  56         fd = *socket->fd_ptr;
  57         if (fd < 0) {
  58                 goto error;
  59         }
  60
  61         size = lttcomm_send_unix_sock(fd, msg, len);
  62         if (size < 0) {
  63                 /* The above call will print a PERROR on error. */
  64                 DBG("Error when sending data to consumer on sock %d", fd);
  65                 /*
  66                  * At this point, the socket is not usable anymore thus closing it and
  67                  * setting the file descriptor to -1 so it is not reused.
  68                  */
  69
  70                 /* This call will PERROR on error. */
  71                 (void) lttcomm_close_unix_sock(fd);
  72                 *socket->fd_ptr = -1;
  73                 goto error;
  74         }
  75
  76         return 0;
  77
  78 error:
  79         return -1;
  80 }
  81
  82 /*
  83  * Receive a data payload using a given consumer socket of size len.
  84  *
  85  * The consumer socket lock MUST be acquired before calling this since this
  86  * function can change the fd value.
  87  *
  88  * Return 0 on success else a negative value on error.
  89  */
  90 int consumer_socket_recv(struct consumer_socket *socket, void *msg, size_t len)
  91 {
  92         int fd;
  93         ssize_t size;
  94
  95         assert(socket);
  96         assert(socket->fd_ptr);
  97         assert(msg);
  98
  99         /* Consumer socket is invalid. Stopping. */
 100         fd = *socket->fd_ptr;
 101         if (fd < 0) {
 102                 goto error;
 103         }
 104
 105         size = lttcomm_recv_unix_sock(fd, msg, len);
 106         if (size <= 0) {
 107                 /* The above call will print a PERROR on error. */
 108                 DBG("Error when receiving data from the consumer socket %d", fd);
 109                 /*
 110                  * At this point, the socket is not usable anymore thus closing it and
 111                  * setting the file descriptor to -1 so it is not reused.
 112                  */
 113
 114                 /* This call will PERROR on error. */
 115                 (void) lttcomm_close_unix_sock(fd);
 116                 *socket->fd_ptr = -1;
 117                 goto error;
 118         }
 119
 120         return 0;
 121
 122 error:
 123         return -1;
 124 }
 125
 126 /*
 127  * Receive a reply command status message from the consumer. Consumer socket
 128  * lock MUST be acquired before calling this function.
 129  *
 130  * Return 0 on success, -1 on recv error or a negative lttng error code which
 131  * was possibly returned by the consumer.
 132  */
 133 int consumer_recv_status_reply(struct consumer_socket *sock)
 134 {
 135         int ret;
 136         struct lttcomm_consumer_status_msg reply;
 137
 138         assert(sock);
 139
 140         ret = consumer_socket_recv(sock, &reply, sizeof(reply));
 141         if (ret < 0) {
 142                 goto end;
 143         }
 144
 145         if (reply.ret_code == LTTCOMM_CONSUMERD_SUCCESS) {
 146                 /* All good. */
 147                 ret = 0;
 148         } else {
 149                 ret = -reply.ret_code;
 150                 DBG("Consumer ret code %d", ret);
 151         }
 152
 153 end:
 154         return ret;
 155 }
 156
 157 /*
 158  * Once the ASK_CHANNEL command is sent to the consumer, the channel
 159  * information are sent back. This call receives that data and populates key
 160  * and stream_count.
 161  *
 162  * On success return 0 and both key and stream_count are set. On error, a
 163  * negative value is sent back and both parameters are untouched.
 164  */
 165 int consumer_recv_status_channel(struct consumer_socket *sock,
 166                 uint64_t *key, unsigned int *stream_count)
 167 {
 168         int ret;
 169         struct lttcomm_consumer_status_channel reply;
 170
 171         assert(sock);
 172         assert(stream_count);
 173         assert(key);
 174
 175         ret = consumer_socket_recv(sock, &reply, sizeof(reply));
 176         if (ret < 0) {
 177                 goto end;
 178         }
 179
 180         /* An error is possible so don't touch the key and stream_count. */
 181         if (reply.ret_code != LTTCOMM_CONSUMERD_SUCCESS) {
 182                 ret = -1;
 183                 goto end;
 184         }
 185
 186         *key = reply.key;
 187         *stream_count = reply.stream_count;
 188         ret = 0;
 189
 190 end:
 191         return ret;
 192 }
 193
 194 /*
 195  * Send destroy relayd command to consumer.
 196  *
 197  * On success return positive value. On error, negative value.
 198  */
 199 int consumer_send_destroy_relayd(struct consumer_socket *sock,
 200                 struct consumer_output *consumer)
 201 {
 202         int ret;
 203         struct lttcomm_consumer_msg msg;
 204
 205         assert(consumer);
 206         assert(sock);
 207
 208         DBG2("Sending destroy relayd command to consumer sock %d", *sock->fd_ptr);
 209
 210         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
 475         output->socks = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 476
 477 error:
 478         return output;
 479 }
 480
 481 /*
 482  * Iterate over the consumer output socket hash table and destroy them. The
 483  * socket file descriptor are only closed if the consumer output was
 484  * registered meaning it's an external consumer.
 485  */
 486 void consumer_destroy_output_sockets(struct consumer_output *obj)
 487 {
 488         struct lttng_ht_iter iter;
 489         struct consumer_socket *socket;
 490
 491         if (!obj->socks) {
 492                 return;
 493         }
 494
 495         rcu_read_lock();
 496         cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 497                 consumer_del_socket(socket, obj);
 498                 consumer_destroy_socket(socket);
 499         }
 500         rcu_read_unlock();
 501 }
 502
 503 /*
 504  * Delete the consumer_output object from the list and free the ptr.
 505  *
 506  * Should *NOT* be called with RCU read-side lock held.
 507  */
 508 void consumer_destroy_output(struct consumer_output *obj)
 509 {
 510         if (obj == NULL) {
 511                 return;
 512         }
 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  * Copy consumer output and returned the newly allocated copy.
 526  *
 527  * Should *NOT* be called with RCU read-side lock held.
 528  */
 529 struct consumer_output *consumer_copy_output(struct consumer_output *obj)
 530 {
 531         int ret;
 532         struct lttng_ht *tmp_ht_ptr;
 533         struct consumer_output *output;
 534
 535         assert(obj);
 536
 537         output = consumer_create_output(obj->type);
 538         if (output == NULL) {
 539                 goto error;
 540         }
 541         /* Avoid losing the HT reference after the memcpy() */
 542         tmp_ht_ptr = output->socks;
 543
 544         memcpy(output, obj, sizeof(struct consumer_output));
 545
 546         /* Putting back the HT pointer and start copying socket(s). */
 547         output->socks = tmp_ht_ptr;
 548
 549         ret = consumer_copy_sockets(output, obj);
 550         if (ret < 0) {
 551                 goto malloc_error;
 552         }
 553
 554 error:
 555         return output;
 556
 557 malloc_error:
 558         consumer_destroy_output(output);
 559         return NULL;
 560 }
 561
 562 /*
 563  * Copy consumer sockets from src to dst.
 564  *
 565  * Return 0 on success or else a negative value.
 566  */
 567 int consumer_copy_sockets(struct consumer_output *dst,
 568                 struct consumer_output *src)
 569 {
 570         int ret = 0;
 571         struct lttng_ht_iter iter;
 572         struct consumer_socket *socket, *copy_sock;
 573
 574         assert(dst);
 575         assert(src);
 576
 577         rcu_read_lock();
 578         cds_lfht_for_each_entry(src->socks->ht, &iter.iter, socket, node.node) {
 579                 /* Ignore socket that are already there. */
 580                 copy_sock = consumer_find_socket(*socket->fd_ptr, dst);
 581                 if (copy_sock) {
 582                         continue;
 583                 }
 584
 585                 /* Create new socket object. */
 586                 copy_sock = consumer_allocate_socket(socket->fd_ptr);
 587                 if (copy_sock == NULL) {
 588                         rcu_read_unlock();
 589                         ret = -ENOMEM;
 590                         goto error;
 591                 }
 592
 593                 copy_sock->registered = socket->registered;
 594                 /*
 595                  * This is valid because this lock is shared accross all consumer
 596                  * object being the global lock of the consumer data structure of the
 597                  * session daemon.
 598                  */
 599                 copy_sock->lock = socket->lock;
 600                 consumer_add_socket(copy_sock, dst);
 601         }
 602         rcu_read_unlock();
 603
 604 error:
 605         return ret;
 606 }
 607
 608 /*
 609  * Set network URI to the consumer output object.
 610  *
 611  * Return 0 on success. Return 1 if the URI were equal. Else, negative value on
 612  * error.
 613  */
 614 int consumer_set_network_uri(struct consumer_output *obj,
 615                 struct lttng_uri *uri)
 616 {
 617         int ret;
 618         char tmp_path[PATH_MAX];
 619         char hostname[HOST_NAME_MAX];
 620         struct lttng_uri *dst_uri = NULL;
 621
 622         /* Code flow error safety net. */
 623         assert(obj);
 624         assert(uri);
 625
 626         switch (uri->stype) {
 627         case LTTNG_STREAM_CONTROL:
 628                 dst_uri = &obj->dst.net.control;
 629                 obj->dst.net.control_isset = 1;
 630                 if (uri->port == 0) {
 631                         /* Assign default port. */
 632                         uri->port = DEFAULT_NETWORK_CONTROL_PORT;
 633                 } else {
 634                         if (obj->dst.net.data_isset && uri->port ==
 635                                         obj->dst.net.data.port) {
 636                                 ret = -LTTNG_ERR_INVALID;
 637                                 goto error;
 638                         }
 639                 }
 640                 DBG3("Consumer control URI set with port %d", uri->port);
 641                 break;
 642         case LTTNG_STREAM_DATA:
 643                 dst_uri = &obj->dst.net.data;
 644                 obj->dst.net.data_isset = 1;
 645                 if (uri->port == 0) {
 646                         /* Assign default port. */
 647                         uri->port = DEFAULT_NETWORK_DATA_PORT;
 648                 } else {
 649                         if (obj->dst.net.control_isset && uri->port ==
 650                                         obj->dst.net.control.port) {
 651                                 ret = -LTTNG_ERR_INVALID;
 652                                 goto error;
 653                         }
 654                 }
 655                 DBG3("Consumer data URI set with port %d", uri->port);
 656                 break;
 657         default:
 658                 ERR("Set network uri type unknown %d", uri->stype);
 659                 ret = -LTTNG_ERR_INVALID;
 660                 goto error;
 661         }
 662
 663         ret = uri_compare(dst_uri, uri);
 664         if (!ret) {
 665                 /* Same URI, don't touch it and return success. */
 666                 DBG3("URI network compare are the same");
 667                 goto equal;
 668         }
 669
 670         /* URIs were not equal, replacing it. */
 671         memset(dst_uri, 0, sizeof(struct lttng_uri));
 672         memcpy(dst_uri, uri, sizeof(struct lttng_uri));
 673         obj->type = CONSUMER_DST_NET;
 674
 675         /* Handle subdir and add hostname in front. */
 676         if (dst_uri->stype == LTTNG_STREAM_CONTROL) {
 677                 /* Get hostname to append it in the pathname */
 678                 ret = gethostname(hostname, sizeof(hostname));
 679                 if (ret < 0) {
 680                         PERROR("gethostname. Fallback on default localhost");
 681                         strncpy(hostname, "localhost", sizeof(hostname));
 682                 }
 683                 hostname[sizeof(hostname) - 1] = '\0';
 684
 685                 /* Setup consumer subdir if none present in the control URI */
 686                 if (strlen(dst_uri->subdir) == 0) {
 687                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 688                                         hostname, obj->subdir);
 689                 } else {
 690                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 691                                         hostname, dst_uri->subdir);
 692                 }
 693                 if (ret < 0) {
 694                         PERROR("snprintf set consumer uri subdir");
 695                         ret = -LTTNG_ERR_NOMEM;
 696                         goto error;
 697                 }
 698
 699                 strncpy(obj->subdir, tmp_path, sizeof(obj->subdir));
 700                 DBG3("Consumer set network uri subdir path %s", tmp_path);
 701         }
 702
 703         return 0;
 704 equal:
 705         return 1;
 706 error:
 707         return ret;
 708 }
 709
 710 /*
 711  * Send file descriptor to consumer via sock.
 712  */
 713 int consumer_send_fds(struct consumer_socket *sock, int *fds, size_t nb_fd)
 714 {
 715         int ret;
 716
 717         assert(fds);
 718         assert(sock);
 719         assert(nb_fd > 0);
 720
 721         ret = lttcomm_send_fds_unix_sock(*sock->fd_ptr, fds, nb_fd);
 722         if (ret < 0) {
 723                 /* The above call will print a PERROR on error. */
 724                 DBG("Error when sending consumer fds on sock %d", *sock->fd_ptr);
 725                 goto error;
 726         }
 727
 728         ret = consumer_recv_status_reply(sock);
 729
 730 error:
 731         return ret;
 732 }
 733
 734 /*
 735  * Consumer send communication message structure to consumer.
 736  */
 737 int consumer_send_msg(struct consumer_socket *sock,
 738                 struct lttcomm_consumer_msg *msg)
 739 {
 740         int ret;
 741
 742         assert(msg);
 743         assert(sock);
 744
 745         ret = consumer_socket_send(sock, msg, sizeof(struct lttcomm_consumer_msg));
 746         if (ret < 0) {
 747                 goto error;
 748         }
 749
 750         ret = consumer_recv_status_reply(sock);
 751
 752 error:
 753         return ret;
 754 }
 755
 756 /*
 757  * Consumer send channel communication message structure to consumer.
 758  */
 759 int consumer_send_channel(struct consumer_socket *sock,
 760                 struct lttcomm_consumer_msg *msg)
 761 {
 762         int ret;
 763
 764         assert(msg);
 765         assert(sock);
 766
 767         ret = consumer_send_msg(sock, msg);
 768         if (ret < 0) {
 769                 goto error;
 770         }
 771
 772 error:
 773         return ret;
 774 }
 775
 776 /*
 777  * Populate the given consumer msg structure with the ask_channel command
 778  * information.
 779  */
 780 void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 781                 uint64_t subbuf_size,
 782                 uint64_t num_subbuf,
 783                 int overwrite,
 784                 unsigned int switch_timer_interval,
 785                 unsigned int read_timer_interval,
 786                 unsigned int live_timer_interval,
 787                 int output,
 788                 int type,
 789                 uint64_t session_id,
 790                 const char *pathname,
 791                 const char *name,
 792                 uid_t uid,
 793                 gid_t gid,
 794                 uint64_t relayd_id,
 795                 uint64_t key,
 796                 unsigned char *uuid,
 797                 uint32_t chan_id,
 798                 uint64_t tracefile_size,
 799                 uint64_t tracefile_count,
 800                 uint64_t session_id_per_pid,
 801                 unsigned int monitor,
 802                 uint32_t ust_app_uid)
 803 {
 804         assert(msg);
 805
 806         /* Zeroed structure */
 807         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 808
 809         msg->cmd_type = LTTNG_CONSUMER_ASK_CHANNEL_CREATION;
 810         msg->u.ask_channel.subbuf_size = subbuf_size;
 811         msg->u.ask_channel.num_subbuf = num_subbuf ;
 812         msg->u.ask_channel.overwrite = overwrite;
 813         msg->u.ask_channel.switch_timer_interval = switch_timer_interval;
 814         msg->u.ask_channel.read_timer_interval = read_timer_interval;
 815         msg->u.ask_channel.live_timer_interval = live_timer_interval;
 816         msg->u.ask_channel.output = output;
 817         msg->u.ask_channel.type = type;
 818         msg->u.ask_channel.session_id = session_id;
 819         msg->u.ask_channel.session_id_per_pid = session_id_per_pid;
 820         msg->u.ask_channel.uid = uid;
 821         msg->u.ask_channel.gid = gid;
 822         msg->u.ask_channel.relayd_id = relayd_id;
 823         msg->u.ask_channel.key = key;
 824         msg->u.ask_channel.chan_id = chan_id;
 825         msg->u.ask_channel.tracefile_size = tracefile_size;
 826         msg->u.ask_channel.tracefile_count = tracefile_count;
 827         msg->u.ask_channel.monitor = monitor;
 828         msg->u.ask_channel.ust_app_uid = ust_app_uid;
 829
 830         memcpy(msg->u.ask_channel.uuid, uuid, sizeof(msg->u.ask_channel.uuid));
 831
 832         if (pathname) {
 833                 strncpy(msg->u.ask_channel.pathname, pathname,
 834                                 sizeof(msg->u.ask_channel.pathname));
 835                 msg->u.ask_channel.pathname[sizeof(msg->u.ask_channel.pathname)-1] = '\0';
 836         }
 837
 838         strncpy(msg->u.ask_channel.name, name, sizeof(msg->u.ask_channel.name));
 839         msg->u.ask_channel.name[sizeof(msg->u.ask_channel.name) - 1] = '\0';
 840 }
 841
 842 /*
 843  * Init channel communication message structure.
 844  */
 845 void consumer_init_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 846                 enum lttng_consumer_command cmd,
 847                 uint64_t channel_key,
 848                 uint64_t session_id,
 849                 const char *pathname,
 850                 uid_t uid,
 851                 gid_t gid,
 852                 uint64_t relayd_id,
 853                 const char *name,
 854                 unsigned int nb_init_streams,
 855                 enum lttng_event_output output,
 856                 int type,
 857                 uint64_t tracefile_size,
 858                 uint64_t tracefile_count,
 859                 unsigned int monitor,
 860                 unsigned int live_timer_interval)
 861 {
 862         assert(msg);
 863
 864         /* Zeroed structure */
 865         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 866
 867         /* Send channel */
 868         msg->cmd_type = cmd;
 869         msg->u.channel.channel_key = channel_key;
 870         msg->u.channel.session_id = session_id;
 871         msg->u.channel.uid = uid;
 872         msg->u.channel.gid = gid;
 873         msg->u.channel.relayd_id = relayd_id;
 874         msg->u.channel.nb_init_streams = nb_init_streams;
 875         msg->u.channel.output = output;
 876         msg->u.channel.type = type;
 877         msg->u.channel.tracefile_size = tracefile_size;
 878         msg->u.channel.tracefile_count = tracefile_count;
 879         msg->u.channel.monitor = monitor;
 880         msg->u.channel.live_timer_interval = live_timer_interval;
 881
 882         strncpy(msg->u.channel.pathname, pathname,
 883                         sizeof(msg->u.channel.pathname));
 884         msg->u.channel.pathname[sizeof(msg->u.channel.pathname) - 1] = '\0';
 885
 886         strncpy(msg->u.channel.name, name, sizeof(msg->u.channel.name));
 887         msg->u.channel.name[sizeof(msg->u.channel.name) - 1] = '\0';
 888 }
 889
 890 /*
 891  * Init stream communication message structure.
 892  */
 893 void consumer_init_stream_comm_msg(struct lttcomm_consumer_msg *msg,
 894                 enum lttng_consumer_command cmd,
 895                 uint64_t channel_key,
 896                 uint64_t stream_key,
 897                 int cpu)
 898 {
 899         assert(msg);
 900
 901         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 902
 903         msg->cmd_type = cmd;
 904         msg->u.stream.channel_key = channel_key;
 905         msg->u.stream.stream_key = stream_key;
 906         msg->u.stream.cpu = cpu;
 907 }
 908
 909 /*
 910  * Send stream communication structure to the consumer.
 911  */
 912 int consumer_send_stream(struct consumer_socket *sock,
 913                 struct consumer_output *dst, struct lttcomm_consumer_msg *msg,
 914                 int *fds, size_t nb_fd)
 915 {
 916         int ret;
 917
 918         assert(msg);
 919         assert(dst);
 920         assert(sock);
 921         assert(fds);
 922
 923         ret = consumer_send_msg(sock, msg);
 924         if (ret < 0) {
 925                 goto error;
 926         }
 927
 928         ret = consumer_send_fds(sock, fds, nb_fd);
 929         if (ret < 0) {
 930                 goto error;
 931         }
 932
 933 error:
 934         return ret;
 935 }
 936
 937 /*
 938  * Send relayd socket to consumer associated with a session name.
 939  *
 940  * On success return positive value. On error, negative value.
 941  */
 942 int consumer_send_relayd_socket(struct consumer_socket *consumer_sock,
 943                 struct lttcomm_relayd_sock *rsock, struct consumer_output *consumer,
 944                 enum lttng_stream_type type, uint64_t session_id,
 945                 char *session_name, char *hostname, int session_live_timer)
 946 {
 947         int ret;
 948         struct lttcomm_consumer_msg msg;
 949
 950         /* Code flow error. Safety net. */
 951         assert(rsock);
 952         assert(consumer);
 953         assert(consumer_sock);
 954
 955         /* Bail out if consumer is disabled */
 956         if (!consumer->enabled) {
 957                 ret = LTTNG_OK;
 958                 goto error;
 959         }
 960
 961         if (type == LTTNG_STREAM_CONTROL) {
 962                 ret = relayd_create_session(rsock,
 963                                 &msg.u.relayd_sock.relayd_session_id,
 964                                 session_name, hostname, session_live_timer,
 965                                 consumer->snapshot);
 966                 if (ret < 0) {
 967                         /* Close the control socket. */
 968                         (void) relayd_close(rsock);
 969                         goto error;
 970                 }
 971         }
 972
 973         msg.cmd_type = LTTNG_CONSUMER_ADD_RELAYD_SOCKET;
 974         /*
 975          * Assign network consumer output index using the temporary consumer since
 976          * this call should only be made from within a set_consumer_uri() function
 977          * call in the session daemon.
 978          */
 979         msg.u.relayd_sock.net_index = consumer->net_seq_index;
 980         msg.u.relayd_sock.type = type;
 981         msg.u.relayd_sock.session_id = session_id;
 982         memcpy(&msg.u.relayd_sock.sock, rsock, sizeof(msg.u.relayd_sock.sock));
 983
 984         DBG3("Sending relayd sock info to consumer on %d", *consumer_sock->fd_ptr);
 985         ret = consumer_send_msg(consumer_sock, &msg);
 986         if (ret < 0) {
 987                 goto error;
 988         }
 989
 990         DBG3("Sending relayd socket file descriptor to consumer");
 991         ret = consumer_send_fds(consumer_sock, &rsock->sock.fd, 1);
 992         if (ret < 0) {
 993                 goto error;
 994         }
 995
 996         DBG2("Consumer relayd socket sent");
 997
 998 error:
 999         return ret;
1000 }
1001
1002 /*
1003  * Set consumer subdirectory using the session name and a generated datetime if
1004  * needed. This is appended to the current subdirectory.
1005  */
1006 int consumer_set_subdir(struct consumer_output *consumer,
1007                 const char *session_name)
1008 {
1009         int ret = 0;
1010         unsigned int have_default_name = 0;
1011         char datetime[16], tmp_path[PATH_MAX];
1012         time_t rawtime;
1013         struct tm *timeinfo;
1014
1015         assert(consumer);
1016         assert(session_name);
1017
1018         memset(tmp_path, 0, sizeof(tmp_path));
1019
1020         /* Flag if we have a default session. */
1021         if (strncmp(session_name, DEFAULT_SESSION_NAME "-",
1022                                 strlen(DEFAULT_SESSION_NAME) + 1) == 0) {
1023                 have_default_name = 1;
1024         } else {
1025                 /* Get date and time for session path */
1026                 time(&rawtime);
1027                 timeinfo = localtime(&rawtime);
1028                 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
1029         }
1030
1031         if (have_default_name) {
1032                 ret = snprintf(tmp_path, sizeof(tmp_path),
1033                                 "%s/%s", consumer->subdir, session_name);
1034         } else {
1035                 ret = snprintf(tmp_path, sizeof(tmp_path),
1036                                 "%s/%s-%s/", consumer->subdir, session_name, datetime);
1037         }
1038         if (ret < 0) {
1039                 PERROR("snprintf session name date");
1040                 goto error;
1041         }
1042
1043         strncpy(consumer->subdir, tmp_path, sizeof(consumer->subdir));
1044         DBG2("Consumer subdir set to %s", consumer->subdir);
1045
1046 error:
1047         return ret;
1048 }
1049
1050 /*
1051  * Ask the consumer if the data is ready to read (NOT pending) for the specific
1052  * session id.
1053  *
1054  * This function has a different behavior with the consumer i.e. that it waits
1055  * for a reply from the consumer if yes or no the data is pending.
1056  */
1057 int consumer_is_data_pending(uint64_t session_id,
1058                 struct consumer_output *consumer)
1059 {
1060         int ret;
1061         int32_t ret_code = 0;  /* Default is that the data is NOT pending */
1062         struct consumer_socket *socket;
1063         struct lttng_ht_iter iter;
1064         struct lttcomm_consumer_msg msg;
1065
1066         assert(consumer);
1067
1068         msg.cmd_type = LTTNG_CONSUMER_DATA_PENDING;
1069
1070         msg.u.data_pending.session_id = session_id;
1071
1072         DBG3("Consumer data pending for id %" PRIu64, session_id);
1073
1074         /* Send command for each consumer */
1075         rcu_read_lock();
1076         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
1077                         node.node) {
1078                 pthread_mutex_lock(socket->lock);
1079                 ret = consumer_socket_send(socket, &msg, sizeof(msg));
1080                 if (ret < 0) {
1081                         pthread_mutex_unlock(socket->lock);
1082                         goto error_unlock;
1083                 }
1084
1085                 /*
1086                  * No need for a recv reply status because the answer to the command is
1087                  * the reply status message.
1088                  */
1089
1090                 ret = consumer_socket_recv(socket, &ret_code, sizeof(ret_code));
1091                 if (ret < 0) {
1092                         pthread_mutex_unlock(socket->lock);
1093                         goto error_unlock;
1094                 }
1095                 pthread_mutex_unlock(socket->lock);
1096
1097                 if (ret_code == 1) {
1098                         break;
1099                 }
1100         }
1101         rcu_read_unlock();
1102
1103         DBG("Consumer data is %s pending for session id %" PRIu64,
1104                         ret_code == 1 ? "" : "NOT", session_id);
1105         return ret_code;
1106
1107 error_unlock:
1108         rcu_read_unlock();
1109         return -1;
1110 }
1111
1112 /*
1113  * Send a flush command to consumer using the given channel key.
1114  *
1115  * Return 0 on success else a negative value.
1116  */
1117 int consumer_flush_channel(struct consumer_socket *socket, uint64_t key)
1118 {
1119         int ret;
1120         struct lttcomm_consumer_msg msg;
1121
1122         assert(socket);
1123
1124         DBG2("Consumer flush channel key %" PRIu64, key);
1125
1126         msg.cmd_type = LTTNG_CONSUMER_FLUSH_CHANNEL;
1127         msg.u.flush_channel.key = key;
1128
1129         pthread_mutex_lock(socket->lock);
1130         health_code_update();
1131
1132         ret = consumer_send_msg(socket, &msg);
1133         if (ret < 0) {
1134                 goto end;
1135         }
1136
1137 end:
1138         health_code_update();
1139         pthread_mutex_unlock(socket->lock);
1140         return ret;
1141 }
1142
1143 /*
1144  * Send a close metdata command to consumer using the given channel key.
1145  *
1146  * Return 0 on success else a negative value.
1147  */
1148 int consumer_close_metadata(struct consumer_socket *socket,
1149                 uint64_t metadata_key)
1150 {
1151         int ret;
1152         struct lttcomm_consumer_msg msg;
1153
1154         assert(socket);
1155
1156         DBG2("Consumer close metadata channel key %" PRIu64, metadata_key);
1157
1158         msg.cmd_type = LTTNG_CONSUMER_CLOSE_METADATA;
1159         msg.u.close_metadata.key = metadata_key;
1160
1161         pthread_mutex_lock(socket->lock);
1162         health_code_update();
1163
1164         ret = consumer_send_msg(socket, &msg);
1165         if (ret < 0) {
1166                 goto end;
1167         }
1168
1169 end:
1170         health_code_update();
1171         pthread_mutex_unlock(socket->lock);
1172         return ret;
1173 }
1174
1175 /*
1176  * Send a setup metdata command to consumer using the given channel key.
1177  *
1178  * Return 0 on success else a negative value.
1179  */
1180 int consumer_setup_metadata(struct consumer_socket *socket,
1181                 uint64_t metadata_key)
1182 {
1183         int ret;
1184         struct lttcomm_consumer_msg msg;
1185
1186         assert(socket);
1187
1188         DBG2("Consumer setup metadata channel key %" PRIu64, metadata_key);
1189
1190         msg.cmd_type = LTTNG_CONSUMER_SETUP_METADATA;
1191         msg.u.setup_metadata.key = metadata_key;
1192
1193         pthread_mutex_lock(socket->lock);
1194         health_code_update();
1195
1196         ret = consumer_send_msg(socket, &msg);
1197         if (ret < 0) {
1198                 goto end;
1199         }
1200
1201 end:
1202         health_code_update();
1203         pthread_mutex_unlock(socket->lock);
1204         return ret;
1205 }
1206
1207 /*
1208  * Send metadata string to consumer. Socket lock MUST be acquired.
1209  *
1210  * Return 0 on success else a negative value.
1211  */
1212 int consumer_push_metadata(struct consumer_socket *socket,
1213                 uint64_t metadata_key, char *metadata_str, size_t len,
1214                 size_t target_offset)
1215 {
1216         int ret;
1217         struct lttcomm_consumer_msg msg;
1218
1219         assert(socket);
1220
1221         DBG2("Consumer push metadata to consumer socket %d", *socket->fd_ptr);
1222
1223         msg.cmd_type = LTTNG_CONSUMER_PUSH_METADATA;
1224         msg.u.push_metadata.key = metadata_key;
1225         msg.u.push_metadata.target_offset = target_offset;
1226         msg.u.push_metadata.len = len;
1227
1228         health_code_update();
1229         ret = consumer_send_msg(socket, &msg);
1230         if (ret < 0 || len == 0) {
1231                 goto end;
1232         }
1233
1234         DBG3("Consumer pushing metadata on sock %d of len %zu", *socket->fd_ptr,
1235                         len);
1236
1237         ret = consumer_socket_send(socket, metadata_str, len);
1238         if (ret < 0) {
1239                 goto end;
1240         }
1241
1242         health_code_update();
1243         ret = consumer_recv_status_reply(socket);
1244         if (ret < 0) {
1245                 goto end;
1246         }
1247
1248 end:
1249         health_code_update();
1250         return ret;
1251 }
1252
1253 /*
1254  * Ask the consumer to snapshot a specific channel using the key.
1255  *
1256  * Return 0 on success or else a negative error.
1257  */
1258 int consumer_snapshot_channel(struct consumer_socket *socket, uint64_t key,
1259                 struct snapshot_output *output, int metadata, uid_t uid, gid_t gid,
1260                 const char *session_path, int wait, int max_stream_size)
1261 {
1262         int ret;
1263         struct lttcomm_consumer_msg msg;
1264
1265         assert(socket);
1266         assert(output);
1267         assert(output->consumer);
1268
1269         DBG("Consumer snapshot channel key %" PRIu64, key);
1270
1271         memset(&msg, 0, sizeof(msg));
1272         msg.cmd_type = LTTNG_CONSUMER_SNAPSHOT_CHANNEL;
1273         msg.u.snapshot_channel.key = key;
1274         msg.u.snapshot_channel.max_stream_size = max_stream_size;
1275         msg.u.snapshot_channel.metadata = metadata;
1276
1277         if (output->consumer->type == CONSUMER_DST_NET) {
1278                 msg.u.snapshot_channel.relayd_id = output->consumer->net_seq_index;
1279                 msg.u.snapshot_channel.use_relayd = 1;
1280                 ret = snprintf(msg.u.snapshot_channel.pathname,
1281                                 sizeof(msg.u.snapshot_channel.pathname),
1282                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->subdir,
1283                                 output->name, output->datetime, output->nb_snapshot,
1284                                 session_path);
1285                 if (ret < 0) {
1286                         ret = -LTTNG_ERR_NOMEM;
1287                         goto error;
1288                 }
1289         } else {
1290                 ret = snprintf(msg.u.snapshot_channel.pathname,
1291                                 sizeof(msg.u.snapshot_channel.pathname),
1292                                 "%s/%s-%s-%" PRIu64 "%s", output->consumer->dst.trace_path,
1293                                 output->name, output->datetime, output->nb_snapshot,
1294                                 session_path);
1295                 if (ret < 0) {
1296                         ret = -LTTNG_ERR_NOMEM;
1297                         goto error;
1298                 }
1299                 msg.u.snapshot_channel.relayd_id = (uint64_t) -1ULL;
1300
1301                 /* Create directory. Ignore if exist. */
1302                 ret = run_as_mkdir_recursive(msg.u.snapshot_channel.pathname,
1303                                 S_IRWXU | S_IRWXG, uid, gid);
1304                 if (ret < 0) {
1305                         if (ret != -EEXIST) {
1306                                 ERR("Trace directory creation error");
1307                                 goto error;
1308                         }
1309                 }
1310         }
1311
1312         health_code_update();
1313         ret = consumer_send_msg(socket, &msg);
1314         if (ret < 0) {
1315                 goto error;
1316         }
1317
1318 error:
1319         health_code_update();
1320         return ret;
1321 }