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
  36 /*
  37  * Receive a reply command status message from the consumer. Consumer socket
  38  * lock MUST be acquired before calling this function.
  39  *
  40  * Return 0 on success, -1 on recv error or a negative lttng error code which
  41  * was possibly returned by the consumer.
  42  */
  43 int consumer_recv_status_reply(struct consumer_socket *sock)
  44 {
  45         int ret;
  46         struct lttcomm_consumer_status_msg reply;
  47
  48         assert(sock);
  49
  50         ret = lttcomm_recv_unix_sock(sock->fd, &reply, sizeof(reply));
  51         if (ret <= 0) {
  52                 if (ret == 0) {
  53                         /* Orderly shutdown. Don't return 0 which means success. */
  54                         ret = -1;
  55                 }
  56                 /* The above call will print a PERROR on error. */
  57                 DBG("Fail to receive status reply on sock %d", sock->fd);
  58                 goto end;
  59         }
  60
  61         if (reply.ret_code == LTTNG_OK) {
  62                 /* All good. */
  63                 ret = 0;
  64         } else {
  65                 ret = -reply.ret_code;
  66                 DBG("Consumer ret code %d", ret);
  67         }
  68
  69 end:
  70         return ret;
  71 }
  72
  73 /*
  74  * Once the ASK_CHANNEL command is sent to the consumer, the channel
  75  * information are sent back. This call receives that data and populates key
  76  * and stream_count.
  77  *
  78  * On success return 0 and both key and stream_count are set. On error, a
  79  * negative value is sent back and both parameters are untouched.
  80  */
  81 int consumer_recv_status_channel(struct consumer_socket *sock,
  82                 uint64_t *key, unsigned int *stream_count)
  83 {
  84         int ret;
  85         struct lttcomm_consumer_status_channel reply;
  86
  87         assert(sock);
  88         assert(stream_count);
  89         assert(key);
  90
  91         ret = lttcomm_recv_unix_sock(sock->fd, &reply, sizeof(reply));
  92         if (ret <= 0) {
  93                 if (ret == 0) {
  94                         /* Orderly shutdown. Don't return 0 which means success. */
  95                         ret = -1;
  96                 }
  97                 /* The above call will print a PERROR on error. */
  98                 DBG("Fail to receive status reply on sock %d", sock->fd);
  99                 goto end;
 100         }
 101
 102         /* An error is possible so don't touch the key and stream_count. */
 103         if (reply.ret_code != LTTNG_OK) {
 104                 ret = -1;
 105                 goto end;
 106         }
 107
 108         *key = reply.key;
 109         *stream_count = reply.stream_count;
 110
 111 end:
 112         return ret;
 113 }
 114
 115 /*
 116  * Send destroy relayd command to consumer.
 117  *
 118  * On success return positive value. On error, negative value.
 119  */
 120 int consumer_send_destroy_relayd(struct consumer_socket *sock,
 121                 struct consumer_output *consumer)
 122 {
 123         int ret;
 124         struct lttcomm_consumer_msg msg;
 125
 126         assert(consumer);
 127         assert(sock);
 128
 129         DBG2("Sending destroy relayd command to consumer sock %d", sock->fd);
 130
 131         /* Bail out if consumer is disabled */
 132         if (!consumer->enabled) {
 133                 ret = LTTNG_OK;
 134                 DBG3("Consumer is disabled");
 135                 goto error;
 136         }
 137
 138         msg.cmd_type = LTTNG_CONSUMER_DESTROY_RELAYD;
 139         msg.u.destroy_relayd.net_seq_idx = consumer->net_seq_index;
 140
 141         pthread_mutex_lock(sock->lock);
 142         ret = lttcomm_send_unix_sock(sock->fd, &msg, sizeof(msg));
 143         if (ret < 0) {
 144                 /* Indicate that the consumer is probably closing at this point. */
 145                 DBG("send consumer destroy relayd command");
 146                 goto error_send;
 147         }
 148
 149         /* Don't check the return value. The caller will do it. */
 150         ret = consumer_recv_status_reply(sock);
 151
 152         DBG2("Consumer send destroy relayd command done");
 153
 154 error_send:
 155         pthread_mutex_unlock(sock->lock);
 156 error:
 157         return ret;
 158 }
 159
 160 /*
 161  * For each consumer socket in the consumer output object, send a destroy
 162  * relayd command.
 163  */
 164 void consumer_output_send_destroy_relayd(struct consumer_output *consumer)
 165 {
 166         struct lttng_ht_iter iter;
 167         struct consumer_socket *socket;
 168
 169         assert(consumer);
 170
 171         /* Destroy any relayd connection */
 172         if (consumer && consumer->type == CONSUMER_DST_NET) {
 173                 rcu_read_lock();
 174                 cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
 175                                 node.node) {
 176                         int ret;
 177
 178                         /* Send destroy relayd command */
 179                         ret = consumer_send_destroy_relayd(socket, consumer);
 180                         if (ret < 0) {
 181                                 DBG("Unable to send destroy relayd command to consumer");
 182                                 /* Continue since we MUST delete everything at this point. */
 183                         }
 184                 }
 185                 rcu_read_unlock();
 186         }
 187 }
 188
 189 /*
 190  * From a consumer_data structure, allocate and add a consumer socket to the
 191  * consumer output.
 192  *
 193  * Return 0 on success, else negative value on error
 194  */
 195 int consumer_create_socket(struct consumer_data *data,
 196                 struct consumer_output *output)
 197 {
 198         int ret = 0;
 199         struct consumer_socket *socket;
 200
 201         assert(data);
 202
 203         if (output == NULL || data->cmd_sock < 0) {
 204                 /*
 205                  * Not an error. Possible there is simply not spawned consumer or it's
 206                  * disabled for the tracing session asking the socket.
 207                  */
 208                 goto error;
 209         }
 210
 211         rcu_read_lock();
 212         socket = consumer_find_socket(data->cmd_sock, output);
 213         rcu_read_unlock();
 214         if (socket == NULL) {
 215                 socket = consumer_allocate_socket(data->cmd_sock);
 216                 if (socket == NULL) {
 217                         ret = -1;
 218                         goto error;
 219                 }
 220
 221                 socket->registered = 0;
 222                 socket->lock = &data->lock;
 223                 rcu_read_lock();
 224                 consumer_add_socket(socket, output);
 225                 rcu_read_unlock();
 226         }
 227
 228         DBG3("Consumer socket created (fd: %d) and added to output",
 229                         data->cmd_sock);
 230
 231 error:
 232         return ret;
 233 }
 234
 235 /*
 236  * Return the consumer socket from the given consumer output with the right
 237  * bitness. On error, returns NULL.
 238  *
 239  * The caller MUST acquire a rcu read side lock and keep it until the socket
 240  * object reference is not needed anymore.
 241  */
 242 struct consumer_socket *consumer_find_socket_by_bitness(int bits,
 243                 struct consumer_output *consumer)
 244 {
 245         int consumer_fd;
 246         struct consumer_socket *socket = NULL;
 247
 248         switch (bits) {
 249         case 64:
 250                 consumer_fd = uatomic_read(&ust_consumerd64_fd);
 251                 break;
 252         case 32:
 253                 consumer_fd = uatomic_read(&ust_consumerd32_fd);
 254                 break;
 255         default:
 256                 assert(0);
 257                 goto end;
 258         }
 259
 260         socket = consumer_find_socket(consumer_fd, consumer);
 261         if (!socket) {
 262                 ERR("Consumer socket fd %d not found in consumer obj %p",
 263                                 consumer_fd, consumer);
 264         }
 265
 266 end:
 267         return socket;
 268 }
 269
 270 /*
 271  * Find a consumer_socket in a consumer_output hashtable. Read side lock must
 272  * be acquired before calling this function and across use of the
 273  * returned consumer_socket.
 274  */
 275 struct consumer_socket *consumer_find_socket(int key,
 276                 struct consumer_output *consumer)
 277 {
 278         struct lttng_ht_iter iter;
 279         struct lttng_ht_node_ulong *node;
 280         struct consumer_socket *socket = NULL;
 281
 282         /* Negative keys are lookup failures */
 283         if (key < 0 || consumer == NULL) {
 284                 return NULL;
 285         }
 286
 287         lttng_ht_lookup(consumer->socks, (void *)((unsigned long) key),
 288                         &iter);
 289         node = lttng_ht_iter_get_node_ulong(&iter);
 290         if (node != NULL) {
 291                 socket = caa_container_of(node, struct consumer_socket, node);
 292         }
 293
 294         return socket;
 295 }
 296
 297 /*
 298  * Allocate a new consumer_socket and return the pointer.
 299  */
 300 struct consumer_socket *consumer_allocate_socket(int fd)
 301 {
 302         struct consumer_socket *socket = NULL;
 303
 304         socket = zmalloc(sizeof(struct consumer_socket));
 305         if (socket == NULL) {
 306                 PERROR("zmalloc consumer socket");
 307                 goto error;
 308         }
 309
 310         socket->fd = fd;
 311         lttng_ht_node_init_ulong(&socket->node, fd);
 312
 313 error:
 314         return socket;
 315 }
 316
 317 /*
 318  * Add consumer socket to consumer output object. Read side lock must be
 319  * acquired before calling this function.
 320  */
 321 void consumer_add_socket(struct consumer_socket *sock,
 322                 struct consumer_output *consumer)
 323 {
 324         assert(sock);
 325         assert(consumer);
 326
 327         lttng_ht_add_unique_ulong(consumer->socks, &sock->node);
 328 }
 329
 330 /*
 331  * Delte consumer socket to consumer output object. Read side lock must be
 332  * acquired before calling this function.
 333  */
 334 void consumer_del_socket(struct consumer_socket *sock,
 335                 struct consumer_output *consumer)
 336 {
 337         int ret;
 338         struct lttng_ht_iter iter;
 339
 340         assert(sock);
 341         assert(consumer);
 342
 343         iter.iter.node = &sock->node.node;
 344         ret = lttng_ht_del(consumer->socks, &iter);
 345         assert(!ret);
 346 }
 347
 348 /*
 349  * RCU destroy call function.
 350  */
 351 static void destroy_socket_rcu(struct rcu_head *head)
 352 {
 353         struct lttng_ht_node_ulong *node =
 354                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 355         struct consumer_socket *socket =
 356                 caa_container_of(node, struct consumer_socket, node);
 357
 358         free(socket);
 359 }
 360
 361 /*
 362  * Destroy and free socket pointer in a call RCU. Read side lock must be
 363  * acquired before calling this function.
 364  */
 365 void consumer_destroy_socket(struct consumer_socket *sock)
 366 {
 367         assert(sock);
 368
 369         /*
 370          * We DO NOT close the file descriptor here since it is global to the
 371          * session daemon and is closed only if the consumer dies or a custom
 372          * consumer was registered,
 373          */
 374         if (sock->registered) {
 375                 DBG3("Consumer socket was registered. Closing fd %d", sock->fd);
 376                 lttcomm_close_unix_sock(sock->fd);
 377         }
 378
 379         call_rcu(&sock->node.head, destroy_socket_rcu);
 380 }
 381
 382 /*
 383  * Allocate and assign data to a consumer_output object.
 384  *
 385  * Return pointer to structure.
 386  */
 387 struct consumer_output *consumer_create_output(enum consumer_dst_type type)
 388 {
 389         struct consumer_output *output = NULL;
 390
 391         output = zmalloc(sizeof(struct consumer_output));
 392         if (output == NULL) {
 393                 PERROR("zmalloc consumer_output");
 394                 goto error;
 395         }
 396
 397         /* By default, consumer output is enabled */
 398         output->enabled = 1;
 399         output->type = type;
 400         output->net_seq_index = (uint64_t) -1ULL;
 401
 402         output->socks = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 403
 404 error:
 405         return output;
 406 }
 407
 408 /*
 409  * Delete the consumer_output object from the list and free the ptr.
 410  */
 411 void consumer_destroy_output(struct consumer_output *obj)
 412 {
 413         if (obj == NULL) {
 414                 return;
 415         }
 416
 417         if (obj->socks) {
 418                 struct lttng_ht_iter iter;
 419                 struct consumer_socket *socket;
 420
 421                 rcu_read_lock();
 422                 cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 423                         consumer_del_socket(socket, obj);
 424                         consumer_destroy_socket(socket);
 425                 }
 426                 rcu_read_unlock();
 427
 428                 /* Finally destroy HT */
 429                 lttng_ht_destroy(obj->socks);
 430         }
 431
 432         free(obj);
 433 }
 434
 435 /*
 436  * Copy consumer output and returned the newly allocated copy.
 437  */
 438 struct consumer_output *consumer_copy_output(struct consumer_output *obj)
 439 {
 440         struct lttng_ht *tmp_ht_ptr;
 441         struct lttng_ht_iter iter;
 442         struct consumer_socket *socket, *copy_sock;
 443         struct consumer_output *output;
 444
 445         assert(obj);
 446
 447         output = consumer_create_output(obj->type);
 448         if (output == NULL) {
 449                 goto error;
 450         }
 451         /* Avoid losing the HT reference after the memcpy() */
 452         tmp_ht_ptr = output->socks;
 453
 454         memcpy(output, obj, sizeof(struct consumer_output));
 455
 456         /* Putting back the HT pointer and start copying socket(s). */
 457         output->socks = tmp_ht_ptr;
 458
 459         rcu_read_lock();
 460         cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 461                 /* Create new socket object. */
 462                 copy_sock = consumer_allocate_socket(socket->fd);
 463                 if (copy_sock == NULL) {
 464                         rcu_read_unlock();
 465                         goto malloc_error;
 466                 }
 467
 468                 copy_sock->registered = socket->registered;
 469                 copy_sock->lock = socket->lock;
 470                 consumer_add_socket(copy_sock, output);
 471         }
 472         rcu_read_unlock();
 473
 474 error:
 475         return output;
 476
 477 malloc_error:
 478         consumer_destroy_output(output);
 479         return NULL;
 480 }
 481
 482 /*
 483  * Set network URI to the consumer output object.
 484  *
 485  * Return 0 on success. Return 1 if the URI were equal. Else, negative value on
 486  * error.
 487  */
 488 int consumer_set_network_uri(struct consumer_output *obj,
 489                 struct lttng_uri *uri)
 490 {
 491         int ret;
 492         char tmp_path[PATH_MAX];
 493         char hostname[HOST_NAME_MAX];
 494         struct lttng_uri *dst_uri = NULL;
 495
 496         /* Code flow error safety net. */
 497         assert(obj);
 498         assert(uri);
 499
 500         switch (uri->stype) {
 501         case LTTNG_STREAM_CONTROL:
 502                 dst_uri = &obj->dst.net.control;
 503                 obj->dst.net.control_isset = 1;
 504                 if (uri->port == 0) {
 505                         /* Assign default port. */
 506                         uri->port = DEFAULT_NETWORK_CONTROL_PORT;
 507                 }
 508                 DBG3("Consumer control URI set with port %d", uri->port);
 509                 break;
 510         case LTTNG_STREAM_DATA:
 511                 dst_uri = &obj->dst.net.data;
 512                 obj->dst.net.data_isset = 1;
 513                 if (uri->port == 0) {
 514                         /* Assign default port. */
 515                         uri->port = DEFAULT_NETWORK_DATA_PORT;
 516                 }
 517                 DBG3("Consumer data URI set with port %d", uri->port);
 518                 break;
 519         default:
 520                 ERR("Set network uri type unknown %d", uri->stype);
 521                 goto error;
 522         }
 523
 524         ret = uri_compare(dst_uri, uri);
 525         if (!ret) {
 526                 /* Same URI, don't touch it and return success. */
 527                 DBG3("URI network compare are the same");
 528                 goto equal;
 529         }
 530
 531         /* URIs were not equal, replacing it. */
 532         memset(dst_uri, 0, sizeof(struct lttng_uri));
 533         memcpy(dst_uri, uri, sizeof(struct lttng_uri));
 534         obj->type = CONSUMER_DST_NET;
 535
 536         /* Handle subdir and add hostname in front. */
 537         if (dst_uri->stype == LTTNG_STREAM_CONTROL) {
 538                 /* Get hostname to append it in the pathname */
 539                 ret = gethostname(hostname, sizeof(hostname));
 540                 if (ret < 0) {
 541                         PERROR("gethostname. Fallback on default localhost");
 542                         strncpy(hostname, "localhost", sizeof(hostname));
 543                 }
 544                 hostname[sizeof(hostname) - 1] = '\0';
 545
 546                 /* Setup consumer subdir if none present in the control URI */
 547                 if (strlen(dst_uri->subdir) == 0) {
 548                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 549                                         hostname, obj->subdir);
 550                 } else {
 551                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 552                                         hostname, dst_uri->subdir);
 553                 }
 554                 if (ret < 0) {
 555                         PERROR("snprintf set consumer uri subdir");
 556                         goto error;
 557                 }
 558
 559                 strncpy(obj->subdir, tmp_path, sizeof(obj->subdir));
 560                 DBG3("Consumer set network uri subdir path %s", tmp_path);
 561         }
 562
 563         return 0;
 564 equal:
 565         return 1;
 566 error:
 567         return -1;
 568 }
 569
 570 /*
 571  * Send file descriptor to consumer via sock.
 572  */
 573 int consumer_send_fds(struct consumer_socket *sock, int *fds, size_t nb_fd)
 574 {
 575         int ret;
 576
 577         assert(fds);
 578         assert(sock);
 579         assert(nb_fd > 0);
 580
 581         ret = lttcomm_send_fds_unix_sock(sock->fd, fds, nb_fd);
 582         if (ret < 0) {
 583                 /* The above call will print a PERROR on error. */
 584                 DBG("Error when sending consumer fds on sock %d", sock->fd);
 585                 goto error;
 586         }
 587
 588         ret = consumer_recv_status_reply(sock);
 589
 590 error:
 591         return ret;
 592 }
 593
 594 /*
 595  * Consumer send communication message structure to consumer.
 596  */
 597 int consumer_send_msg(struct consumer_socket *sock,
 598                 struct lttcomm_consumer_msg *msg)
 599 {
 600         int ret;
 601
 602         assert(msg);
 603         assert(sock);
 604         assert(sock->fd >= 0);
 605
 606         ret = lttcomm_send_unix_sock(sock->fd, msg,
 607                         sizeof(struct lttcomm_consumer_msg));
 608         if (ret < 0) {
 609                 /* The above call will print a PERROR on error. */
 610                 DBG("Error when sending consumer channel on sock %d", sock->fd);
 611                 goto error;
 612         }
 613
 614         ret = consumer_recv_status_reply(sock);
 615
 616 error:
 617         return ret;
 618 }
 619
 620 /*
 621  * Consumer send channel communication message structure to consumer.
 622  */
 623 int consumer_send_channel(struct consumer_socket *sock,
 624                 struct lttcomm_consumer_msg *msg)
 625 {
 626         int ret;
 627
 628         assert(msg);
 629         assert(sock);
 630         assert(sock->fd >= 0);
 631
 632         ret = lttcomm_send_unix_sock(sock->fd, msg,
 633                         sizeof(struct lttcomm_consumer_msg));
 634         if (ret < 0) {
 635                 /* The above call will print a PERROR on error. */
 636                 DBG("Error when sending consumer channel on sock %d", sock->fd);
 637                 goto error;
 638         }
 639
 640         ret = consumer_recv_status_reply(sock);
 641
 642 error:
 643         return ret;
 644 }
 645
 646 /*
 647  * Populate the given consumer msg structure with the ask_channel command
 648  * information.
 649  */
 650 void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 651                 uint64_t subbuf_size,
 652                 uint64_t num_subbuf,
 653                 int overwrite,
 654                 unsigned int switch_timer_interval,
 655                 unsigned int read_timer_interval,
 656                 int output,
 657                 int type,
 658                 uint64_t session_id,
 659                 const char *pathname,
 660                 const char *name,
 661                 uid_t uid,
 662                 gid_t gid,
 663                 uint64_t relayd_id,
 664                 uint64_t key,
 665                 unsigned char *uuid,
 666                 uint32_t chan_id)
 667 {
 668         assert(msg);
 669
 670         /* Zeroed structure */
 671         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 672
 673         msg->cmd_type = LTTNG_CONSUMER_ASK_CHANNEL_CREATION;
 674         msg->u.ask_channel.subbuf_size = subbuf_size;
 675         msg->u.ask_channel.num_subbuf = num_subbuf ;
 676         msg->u.ask_channel.overwrite = overwrite;
 677         msg->u.ask_channel.switch_timer_interval = switch_timer_interval;
 678         msg->u.ask_channel.read_timer_interval = read_timer_interval;
 679         msg->u.ask_channel.output = output;
 680         msg->u.ask_channel.type = type;
 681         msg->u.ask_channel.session_id = session_id;
 682         msg->u.ask_channel.uid = uid;
 683         msg->u.ask_channel.gid = gid;
 684         msg->u.ask_channel.relayd_id = relayd_id;
 685         msg->u.ask_channel.key = key;
 686         msg->u.ask_channel.chan_id = chan_id;
 687
 688         memcpy(msg->u.ask_channel.uuid, uuid, sizeof(msg->u.ask_channel.uuid));
 689
 690         strncpy(msg->u.ask_channel.pathname, pathname,
 691                         sizeof(msg->u.ask_channel.pathname));
 692         msg->u.ask_channel.pathname[sizeof(msg->u.ask_channel.pathname)-1] = '\0';
 693
 694         strncpy(msg->u.ask_channel.name, name, sizeof(msg->u.ask_channel.name));
 695         msg->u.ask_channel.name[sizeof(msg->u.ask_channel.name) - 1] = '\0';
 696 }
 697
 698 /*
 699  * Init channel communication message structure.
 700  */
 701 void consumer_init_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 702                 enum lttng_consumer_command cmd,
 703                 uint64_t channel_key,
 704                 uint64_t session_id,
 705                 const char *pathname,
 706                 uid_t uid,
 707                 gid_t gid,
 708                 uint64_t relayd_id,
 709                 const char *name,
 710                 unsigned int nb_init_streams,
 711                 enum lttng_event_output output,
 712                 int type)
 713 {
 714         assert(msg);
 715
 716         /* Zeroed structure */
 717         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 718
 719         /* Send channel */
 720         msg->cmd_type = cmd;
 721         msg->u.channel.channel_key = channel_key;
 722         msg->u.channel.session_id = session_id;
 723         msg->u.channel.uid = uid;
 724         msg->u.channel.gid = gid;
 725         msg->u.channel.relayd_id = relayd_id;
 726         msg->u.channel.nb_init_streams = nb_init_streams;
 727         msg->u.channel.output = output;
 728         msg->u.channel.type = type;
 729
 730         strncpy(msg->u.channel.pathname, pathname,
 731                         sizeof(msg->u.channel.pathname));
 732         msg->u.channel.pathname[sizeof(msg->u.channel.pathname) - 1] = '\0';
 733
 734         strncpy(msg->u.channel.name, name, sizeof(msg->u.channel.name));
 735         msg->u.channel.name[sizeof(msg->u.channel.name) - 1] = '\0';
 736 }
 737
 738 /*
 739  * Init stream communication message structure.
 740  */
 741 void consumer_init_stream_comm_msg(struct lttcomm_consumer_msg *msg,
 742                 enum lttng_consumer_command cmd,
 743                 uint64_t channel_key,
 744                 uint64_t stream_key,
 745                 int cpu)
 746 {
 747         assert(msg);
 748
 749         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 750
 751         msg->cmd_type = cmd;
 752         msg->u.stream.channel_key = channel_key;
 753         msg->u.stream.stream_key = stream_key;
 754         msg->u.stream.cpu = cpu;
 755 }
 756
 757 /*
 758  * Send stream communication structure to the consumer.
 759  */
 760 int consumer_send_stream(struct consumer_socket *sock,
 761                 struct consumer_output *dst, struct lttcomm_consumer_msg *msg,
 762                 int *fds, size_t nb_fd)
 763 {
 764         int ret;
 765
 766         assert(msg);
 767         assert(dst);
 768         assert(sock);
 769         assert(fds);
 770
 771         /* Send on socket */
 772         ret = lttcomm_send_unix_sock(sock->fd, msg,
 773                         sizeof(struct lttcomm_consumer_msg));
 774         if (ret < 0) {
 775                 /* The above call will print a PERROR on error. */
 776                 DBG("Error when sending consumer stream on sock %d", sock->fd);
 777                 goto error;
 778         }
 779
 780         ret = consumer_recv_status_reply(sock);
 781         if (ret < 0) {
 782                 goto error;
 783         }
 784
 785         ret = consumer_send_fds(sock, fds, nb_fd);
 786         if (ret < 0) {
 787                 goto error;
 788         }
 789
 790 error:
 791         return ret;
 792 }
 793
 794 /*
 795  * Send relayd socket to consumer associated with a session name.
 796  *
 797  * On success return positive value. On error, negative value.
 798  */
 799 int consumer_send_relayd_socket(struct consumer_socket *consumer_sock,
 800                 struct lttcomm_sock *sock, struct consumer_output *consumer,
 801                 enum lttng_stream_type type, uint64_t session_id)
 802 {
 803         int ret;
 804         struct lttcomm_consumer_msg msg;
 805
 806         /* Code flow error. Safety net. */
 807         assert(sock);
 808         assert(consumer);
 809         assert(consumer_sock);
 810
 811         /* Bail out if consumer is disabled */
 812         if (!consumer->enabled) {
 813                 ret = LTTNG_OK;
 814                 goto error;
 815         }
 816
 817         msg.cmd_type = LTTNG_CONSUMER_ADD_RELAYD_SOCKET;
 818         /*
 819          * Assign network consumer output index using the temporary consumer since
 820          * this call should only be made from within a set_consumer_uri() function
 821          * call in the session daemon.
 822          */
 823         msg.u.relayd_sock.net_index = consumer->net_seq_index;
 824         msg.u.relayd_sock.type = type;
 825         msg.u.relayd_sock.session_id = session_id;
 826         memcpy(&msg.u.relayd_sock.sock, sock, sizeof(msg.u.relayd_sock.sock));
 827
 828         DBG3("Sending relayd sock info to consumer on %d", consumer_sock->fd);
 829         ret = lttcomm_send_unix_sock(consumer_sock->fd, &msg, sizeof(msg));
 830         if (ret < 0) {
 831                 /* The above call will print a PERROR on error. */
 832                 DBG("Error when sending relayd sockets on sock %d", sock->fd);
 833                 goto error;
 834         }
 835
 836         ret = consumer_recv_status_reply(consumer_sock);
 837         if (ret < 0) {
 838                 goto error;
 839         }
 840
 841         DBG3("Sending relayd socket file descriptor to consumer");
 842         ret = consumer_send_fds(consumer_sock, &sock->fd, 1);
 843         if (ret < 0) {
 844                 goto error;
 845         }
 846
 847         DBG2("Consumer relayd socket sent");
 848
 849 error:
 850         return ret;
 851 }
 852
 853 /*
 854  * Set consumer subdirectory using the session name and a generated datetime if
 855  * needed. This is appended to the current subdirectory.
 856  */
 857 int consumer_set_subdir(struct consumer_output *consumer,
 858                 const char *session_name)
 859 {
 860         int ret = 0;
 861         unsigned int have_default_name = 0;
 862         char datetime[16], tmp_path[PATH_MAX];
 863         time_t rawtime;
 864         struct tm *timeinfo;
 865
 866         assert(consumer);
 867         assert(session_name);
 868
 869         memset(tmp_path, 0, sizeof(tmp_path));
 870
 871         /* Flag if we have a default session. */
 872         if (strncmp(session_name, DEFAULT_SESSION_NAME "-",
 873                                 strlen(DEFAULT_SESSION_NAME) + 1) == 0) {
 874                 have_default_name = 1;
 875         } else {
 876                 /* Get date and time for session path */
 877                 time(&rawtime);
 878                 timeinfo = localtime(&rawtime);
 879                 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
 880         }
 881
 882         if (have_default_name) {
 883                 ret = snprintf(tmp_path, sizeof(tmp_path),
 884                                 "%s/%s", consumer->subdir, session_name);
 885         } else {
 886                 ret = snprintf(tmp_path, sizeof(tmp_path),
 887                                 "%s/%s-%s/", consumer->subdir, session_name, datetime);
 888         }
 889         if (ret < 0) {
 890                 PERROR("snprintf session name date");
 891                 goto error;
 892         }
 893
 894         strncpy(consumer->subdir, tmp_path, sizeof(consumer->subdir));
 895         DBG2("Consumer subdir set to %s", consumer->subdir);
 896
 897 error:
 898         return ret;
 899 }
 900
 901 /*
 902  * Ask the consumer if the data is ready to read (NOT pending) for the specific
 903  * session id.
 904  *
 905  * This function has a different behavior with the consumer i.e. that it waits
 906  * for a reply from the consumer if yes or no the data is pending.
 907  */
 908 int consumer_is_data_pending(uint64_t session_id,
 909                 struct consumer_output *consumer)
 910 {
 911         int ret;
 912         int32_t ret_code = 0;  /* Default is that the data is NOT pending */
 913         struct consumer_socket *socket;
 914         struct lttng_ht_iter iter;
 915         struct lttcomm_consumer_msg msg;
 916
 917         assert(consumer);
 918
 919         msg.cmd_type = LTTNG_CONSUMER_DATA_PENDING;
 920
 921         msg.u.data_pending.session_id = session_id;
 922
 923         DBG3("Consumer data pending for id %" PRIu64, session_id);
 924
 925         /* Send command for each consumer */
 926         rcu_read_lock();
 927         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
 928                         node.node) {
 929                 /* Code flow error */
 930                 assert(socket->fd >= 0);
 931
 932                 pthread_mutex_lock(socket->lock);
 933
 934                 ret = lttcomm_send_unix_sock(socket->fd, &msg, sizeof(msg));
 935                 if (ret < 0) {
 936                         /* The above call will print a PERROR on error. */
 937                         DBG("Error on consumer is data pending on sock %d", socket->fd);
 938                         pthread_mutex_unlock(socket->lock);
 939                         goto error_unlock;
 940                 }
 941
 942                 /*
 943                  * No need for a recv reply status because the answer to the command is
 944                  * the reply status message.
 945                  */
 946
 947                 ret = lttcomm_recv_unix_sock(socket->fd, &ret_code, sizeof(ret_code));
 948                 if (ret <= 0) {
 949                         if (ret == 0) {
 950                                 /* Orderly shutdown. Don't return 0 which means success. */
 951                                 ret = -1;
 952                         }
 953                         /* The above call will print a PERROR on error. */
 954                         DBG("Error on recv consumer is data pending on sock %d", socket->fd);
 955                         pthread_mutex_unlock(socket->lock);
 956                         goto error_unlock;
 957                 }
 958
 959                 pthread_mutex_unlock(socket->lock);
 960
 961                 if (ret_code == 1) {
 962                         break;
 963                 }
 964         }
 965         rcu_read_unlock();
 966
 967         DBG("Consumer data is %s pending for session id %" PRIu64,
 968                         ret_code == 1 ? "" : "NOT", session_id);
 969         return ret_code;
 970
 971 error_unlock:
 972         rcu_read_unlock();
 973         return -1;
 974 }
 975
 976 /*
 977  * Send a flush command to consumer using the given channel key.
 978  *
 979  * Return 0 on success else a negative value.
 980  */
 981 int consumer_flush_channel(struct consumer_socket *socket, uint64_t key)
 982 {
 983         int ret;
 984         struct lttcomm_consumer_msg msg;
 985
 986         assert(socket);
 987         assert(socket->fd >= 0);
 988
 989         DBG2("Consumer flush channel key %" PRIu64, key);
 990
 991         msg.cmd_type = LTTNG_CONSUMER_FLUSH_CHANNEL;
 992         msg.u.flush_channel.key = key;
 993
 994         pthread_mutex_lock(socket->lock);
 995         health_code_update();
 996
 997         ret = consumer_send_msg(socket, &msg);
 998         if (ret < 0) {
 999                 goto end;
1000         }
1001
1002 end:
1003         health_code_update();
1004         pthread_mutex_unlock(socket->lock);
1005         return ret;
1006 }
1007
1008 /*
1009  * Send a close metdata command to consumer using the given channel key.
1010  *
1011  * Return 0 on success else a negative value.
1012  */
1013 int consumer_close_metadata(struct consumer_socket *socket,
1014                 uint64_t metadata_key)
1015 {
1016         int ret;
1017         struct lttcomm_consumer_msg msg;
1018
1019         assert(socket);
1020         assert(socket->fd >= 0);
1021
1022         DBG2("Consumer close metadata channel key %" PRIu64, metadata_key);
1023
1024         msg.cmd_type = LTTNG_CONSUMER_CLOSE_METADATA;
1025         msg.u.close_metadata.key = metadata_key;
1026
1027         pthread_mutex_lock(socket->lock);
1028         health_code_update();
1029
1030         ret = consumer_send_msg(socket, &msg);
1031         if (ret < 0) {
1032                 goto end;
1033         }
1034
1035 end:
1036         health_code_update();
1037         pthread_mutex_unlock(socket->lock);
1038         return ret;
1039 }
1040
1041 /*
1042  * Send a setup metdata command to consumer using the given channel key.
1043  *
1044  * Return 0 on success else a negative value.
1045  */
1046 int consumer_setup_metadata(struct consumer_socket *socket,
1047                 uint64_t metadata_key)
1048 {
1049         int ret;
1050         struct lttcomm_consumer_msg msg;
1051
1052         assert(socket);
1053         assert(socket->fd >= 0);
1054
1055         DBG2("Consumer setup metadata channel key %" PRIu64, metadata_key);
1056
1057         msg.cmd_type = LTTNG_CONSUMER_SETUP_METADATA;
1058         msg.u.setup_metadata.key = metadata_key;
1059
1060         pthread_mutex_lock(socket->lock);
1061         health_code_update();
1062
1063         ret = consumer_send_msg(socket, &msg);
1064         if (ret < 0) {
1065                 goto end;
1066         }
1067
1068 end:
1069         health_code_update();
1070         pthread_mutex_unlock(socket->lock);
1071         return ret;
1072 }
1073
1074 /*
1075  * Send metadata string to consumer. Socket lock MUST be acquired.
1076  *
1077  * Return 0 on success else a negative value.
1078  */
1079 int consumer_push_metadata(struct consumer_socket *socket,
1080                 uint64_t metadata_key, char *metadata_str, size_t len,
1081                 size_t target_offset)
1082 {
1083         int ret;
1084         struct lttcomm_consumer_msg msg;
1085
1086         assert(socket);
1087         assert(socket->fd >= 0);
1088
1089         DBG2("Consumer push metadata to consumer socket %d", socket->fd);
1090
1091         msg.cmd_type = LTTNG_CONSUMER_PUSH_METADATA;
1092         msg.u.push_metadata.key = metadata_key;
1093         msg.u.push_metadata.target_offset = target_offset;
1094         msg.u.push_metadata.len = len;
1095
1096         health_code_update();
1097         ret = consumer_send_msg(socket, &msg);
1098         if (ret < 0 || len == 0) {
1099                 goto end;
1100         }
1101
1102         DBG3("Consumer pushing metadata on sock %d of len %lu", socket->fd, len);
1103
1104         ret = lttcomm_send_unix_sock(socket->fd, metadata_str, len);
1105         if (ret < 0) {
1106                 goto end;
1107         }
1108
1109         health_code_update();
1110         ret = consumer_recv_status_reply(socket);
1111         if (ret < 0) {
1112                 goto end;
1113         }
1114
1115 end:
1116         health_code_update();
1117         return ret;
1118 }