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
  27 #include <common/common.h>
  28 #include <common/defaults.h>
  29 #include <common/uri.h>
  30
  31 #include "consumer.h"
  32
  33 /*
  34  * Receive a reply command status message from the consumer. Consumer socket
  35  * lock MUST be acquired before calling this function.
  36  *
  37  * Return 0 on success, -1 on recv error or a negative lttng error code which
  38  * was possibly returned by the consumer.
  39  */
  40 int consumer_recv_status_reply(struct consumer_socket *sock)
  41 {
  42         int ret;
  43         struct lttcomm_consumer_status_msg reply;
  44
  45         assert(sock);
  46
  47         ret = lttcomm_recv_unix_sock(sock->fd, &reply, sizeof(reply));
  48         if (ret < 0) {
  49                 PERROR("recv consumer status msg");
  50                 goto end;
  51         }
  52
  53         if (reply.ret_code == LTTNG_OK) {
  54                 /* All good. */
  55                 ret = 0;
  56         } else {
  57                 ret = -reply.ret_code;
  58                 ERR("Consumer ret code %d", reply.ret_code);
  59         }
  60
  61 end:
  62         return ret;
  63 }
  64
  65 /*
  66  * Send destroy relayd command to consumer.
  67  *
  68  * On success return positive value. On error, negative value.
  69  */
  70 int consumer_send_destroy_relayd(struct consumer_socket *sock,
  71                 struct consumer_output *consumer)
  72 {
  73         int ret;
  74         struct lttcomm_consumer_msg msg;
  75
  76         assert(consumer);
  77         assert(sock);
  78
  79         DBG2("Sending destroy relayd command to consumer...");
  80
  81         /* Bail out if consumer is disabled */
  82         if (!consumer->enabled) {
  83                 ret = LTTNG_OK;
  84                 DBG3("Consumer is disabled");
  85                 goto error;
  86         }
  87
  88         msg.cmd_type = LTTNG_CONSUMER_DESTROY_RELAYD;
  89         msg.u.destroy_relayd.net_seq_idx = consumer->net_seq_index;
  90
  91         pthread_mutex_lock(sock->lock);
  92         ret = lttcomm_send_unix_sock(sock->fd, &msg, sizeof(msg));
  93         if (ret < 0) {
  94                 PERROR("send consumer destroy relayd command");
  95                 goto error_send;
  96         }
  97
  98         /* Don't check the return value. The caller will do it. */
  99         ret = consumer_recv_status_reply(sock);
 100
 101         DBG2("Consumer send destroy relayd command done");
 102
 103 error_send:
 104         pthread_mutex_unlock(sock->lock);
 105 error:
 106         return ret;
 107 }
 108
 109 /*
 110  * For each consumer socket in the consumer output object, send a destroy
 111  * relayd command.
 112  */
 113 void consumer_output_send_destroy_relayd(struct consumer_output *consumer)
 114 {
 115         int ret;
 116         struct lttng_ht_iter iter;
 117         struct consumer_socket *socket;
 118
 119         assert(consumer);
 120
 121         /* Destroy any relayd connection */
 122         if (consumer && consumer->type == CONSUMER_DST_NET) {
 123                 rcu_read_lock();
 124                 cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
 125                                 node.node) {
 126                         /* Send destroy relayd command */
 127                         ret = consumer_send_destroy_relayd(socket, consumer);
 128                         if (ret < 0) {
 129                                 ERR("Unable to send destroy relayd command to consumer");
 130                                 /* Continue since we MUST delete everything at this point. */
 131                         }
 132                 }
 133                 rcu_read_unlock();
 134         }
 135 }
 136
 137 /*
 138  * From a consumer_data structure, allocate and add a consumer socket to the
 139  * consumer output.
 140  *
 141  * Return 0 on success, else negative value on error
 142  */
 143 int consumer_create_socket(struct consumer_data *data,
 144                 struct consumer_output *output)
 145 {
 146         int ret = 0;
 147         struct consumer_socket *socket;
 148
 149         assert(data);
 150
 151         if (output == NULL || data->cmd_sock < 0) {
 152                 /*
 153                  * Not an error. Possible there is simply not spawned consumer or it's
 154                  * disabled for the tracing session asking the socket.
 155                  */
 156                 goto error;
 157         }
 158
 159         rcu_read_lock();
 160         socket = consumer_find_socket(data->cmd_sock, output);
 161         rcu_read_unlock();
 162         if (socket == NULL) {
 163                 socket = consumer_allocate_socket(data->cmd_sock);
 164                 if (socket == NULL) {
 165                         ret = -1;
 166                         goto error;
 167                 }
 168
 169                 socket->registered = 0;
 170                 socket->lock = &data->lock;
 171                 rcu_read_lock();
 172                 consumer_add_socket(socket, output);
 173                 rcu_read_unlock();
 174         }
 175
 176         DBG3("Consumer socket created (fd: %d) and added to output",
 177                         data->cmd_sock);
 178
 179 error:
 180         return ret;
 181 }
 182
 183 /*
 184  * Find a consumer_socket in a consumer_output hashtable. Read side lock must
 185  * be acquired before calling this function and across use of the
 186  * returned consumer_socket.
 187  */
 188 struct consumer_socket *consumer_find_socket(int key,
 189                 struct consumer_output *consumer)
 190 {
 191         struct lttng_ht_iter iter;
 192         struct lttng_ht_node_ulong *node;
 193         struct consumer_socket *socket = NULL;
 194
 195         /* Negative keys are lookup failures */
 196         if (key < 0 || consumer == NULL) {
 197                 return NULL;
 198         }
 199
 200         lttng_ht_lookup(consumer->socks, (void *)((unsigned long) key),
 201                         &iter);
 202         node = lttng_ht_iter_get_node_ulong(&iter);
 203         if (node != NULL) {
 204                 socket = caa_container_of(node, struct consumer_socket, node);
 205         }
 206
 207         return socket;
 208 }
 209
 210 /*
 211  * Allocate a new consumer_socket and return the pointer.
 212  */
 213 struct consumer_socket *consumer_allocate_socket(int fd)
 214 {
 215         struct consumer_socket *socket = NULL;
 216
 217         socket = zmalloc(sizeof(struct consumer_socket));
 218         if (socket == NULL) {
 219                 PERROR("zmalloc consumer socket");
 220                 goto error;
 221         }
 222
 223         socket->fd = fd;
 224         lttng_ht_node_init_ulong(&socket->node, fd);
 225
 226 error:
 227         return socket;
 228 }
 229
 230 /*
 231  * Add consumer socket to consumer output object. Read side lock must be
 232  * acquired before calling this function.
 233  */
 234 void consumer_add_socket(struct consumer_socket *sock,
 235                 struct consumer_output *consumer)
 236 {
 237         assert(sock);
 238         assert(consumer);
 239
 240         lttng_ht_add_unique_ulong(consumer->socks, &sock->node);
 241 }
 242
 243 /*
 244  * Delte consumer socket to consumer output object. Read side lock must be
 245  * acquired before calling this function.
 246  */
 247 void consumer_del_socket(struct consumer_socket *sock,
 248                 struct consumer_output *consumer)
 249 {
 250         int ret;
 251         struct lttng_ht_iter iter;
 252
 253         assert(sock);
 254         assert(consumer);
 255
 256         iter.iter.node = &sock->node.node;
 257         ret = lttng_ht_del(consumer->socks, &iter);
 258         assert(!ret);
 259 }
 260
 261 /*
 262  * RCU destroy call function.
 263  */
 264 static void destroy_socket_rcu(struct rcu_head *head)
 265 {
 266         struct lttng_ht_node_ulong *node =
 267                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 268         struct consumer_socket *socket =
 269                 caa_container_of(node, struct consumer_socket, node);
 270
 271         free(socket);
 272 }
 273
 274 /*
 275  * Destroy and free socket pointer in a call RCU. Read side lock must be
 276  * acquired before calling this function.
 277  */
 278 void consumer_destroy_socket(struct consumer_socket *sock)
 279 {
 280         assert(sock);
 281
 282         /*
 283          * We DO NOT close the file descriptor here since it is global to the
 284          * session daemon and is closed only if the consumer dies or a custom
 285          * consumer was registered,
 286          */
 287         if (sock->registered) {
 288                 DBG3("Consumer socket was registered. Closing fd %d", sock->fd);
 289                 lttcomm_close_unix_sock(sock->fd);
 290         }
 291
 292         call_rcu(&sock->node.head, destroy_socket_rcu);
 293 }
 294
 295 /*
 296  * Allocate and assign data to a consumer_output object.
 297  *
 298  * Return pointer to structure.
 299  */
 300 struct consumer_output *consumer_create_output(enum consumer_dst_type type)
 301 {
 302         struct consumer_output *output = NULL;
 303
 304         output = zmalloc(sizeof(struct consumer_output));
 305         if (output == NULL) {
 306                 PERROR("zmalloc consumer_output");
 307                 goto error;
 308         }
 309
 310         /* By default, consumer output is enabled */
 311         output->enabled = 1;
 312         output->type = type;
 313         output->net_seq_index = -1;
 314
 315         output->socks = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 316
 317 error:
 318         return output;
 319 }
 320
 321 /*
 322  * Delete the consumer_output object from the list and free the ptr.
 323  */
 324 void consumer_destroy_output(struct consumer_output *obj)
 325 {
 326         if (obj == NULL) {
 327                 return;
 328         }
 329
 330         if (obj->socks) {
 331                 struct lttng_ht_iter iter;
 332                 struct consumer_socket *socket;
 333
 334                 rcu_read_lock();
 335                 cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 336                         consumer_del_socket(socket, obj);
 337                         consumer_destroy_socket(socket);
 338                 }
 339                 rcu_read_unlock();
 340
 341                 /* Finally destroy HT */
 342                 lttng_ht_destroy(obj->socks);
 343         }
 344
 345         free(obj);
 346 }
 347
 348 /*
 349  * Copy consumer output and returned the newly allocated copy.
 350  */
 351 struct consumer_output *consumer_copy_output(struct consumer_output *obj)
 352 {
 353         struct lttng_ht *tmp_ht_ptr;
 354         struct lttng_ht_iter iter;
 355         struct consumer_socket *socket, *copy_sock;
 356         struct consumer_output *output;
 357
 358         assert(obj);
 359
 360         output = consumer_create_output(obj->type);
 361         if (output == NULL) {
 362                 goto error;
 363         }
 364         /* Avoid losing the HT reference after the memcpy() */
 365         tmp_ht_ptr = output->socks;
 366
 367         memcpy(output, obj, sizeof(struct consumer_output));
 368
 369         /* Putting back the HT pointer and start copying socket(s). */
 370         output->socks = tmp_ht_ptr;
 371
 372         cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
 373                 /* Create new socket object. */
 374                 copy_sock = consumer_allocate_socket(socket->fd);
 375                 if (copy_sock == NULL) {
 376                         goto malloc_error;
 377                 }
 378
 379                 copy_sock->registered = socket->registered;
 380                 copy_sock->lock = socket->lock;
 381                 consumer_add_socket(copy_sock, output);
 382         }
 383
 384 error:
 385         return output;
 386
 387 malloc_error:
 388         consumer_destroy_output(output);
 389         return NULL;
 390 }
 391
 392 /*
 393  * Set network URI to the consumer output object.
 394  *
 395  * Return 0 on success. Return 1 if the URI were equal. Else, negative value on
 396  * error.
 397  */
 398 int consumer_set_network_uri(struct consumer_output *obj,
 399                 struct lttng_uri *uri)
 400 {
 401         int ret;
 402         char tmp_path[PATH_MAX];
 403         char hostname[HOST_NAME_MAX];
 404         struct lttng_uri *dst_uri = NULL;
 405
 406         /* Code flow error safety net. */
 407         assert(obj);
 408         assert(uri);
 409
 410         switch (uri->stype) {
 411         case LTTNG_STREAM_CONTROL:
 412                 dst_uri = &obj->dst.net.control;
 413                 obj->dst.net.control_isset = 1;
 414                 if (uri->port == 0) {
 415                         /* Assign default port. */
 416                         uri->port = DEFAULT_NETWORK_CONTROL_PORT;
 417                 }
 418                 DBG3("Consumer control URI set with port %d", uri->port);
 419                 break;
 420         case LTTNG_STREAM_DATA:
 421                 dst_uri = &obj->dst.net.data;
 422                 obj->dst.net.data_isset = 1;
 423                 if (uri->port == 0) {
 424                         /* Assign default port. */
 425                         uri->port = DEFAULT_NETWORK_DATA_PORT;
 426                 }
 427                 DBG3("Consumer data URI set with port %d", uri->port);
 428                 break;
 429         default:
 430                 ERR("Set network uri type unknown %d", uri->stype);
 431                 goto error;
 432         }
 433
 434         ret = uri_compare(dst_uri, uri);
 435         if (!ret) {
 436                 /* Same URI, don't touch it and return success. */
 437                 DBG3("URI network compare are the same");
 438                 goto equal;
 439         }
 440
 441         /* URIs were not equal, replacing it. */
 442         memset(dst_uri, 0, sizeof(struct lttng_uri));
 443         memcpy(dst_uri, uri, sizeof(struct lttng_uri));
 444         obj->type = CONSUMER_DST_NET;
 445
 446         /* Handle subdir and add hostname in front. */
 447         if (dst_uri->stype == LTTNG_STREAM_CONTROL) {
 448                 /* Get hostname to append it in the pathname */
 449                 ret = gethostname(hostname, sizeof(hostname));
 450                 if (ret < 0) {
 451                         PERROR("gethostname. Fallback on default localhost");
 452                         strncpy(hostname, "localhost", sizeof(hostname));
 453                 }
 454                 hostname[sizeof(hostname) - 1] = '\0';
 455
 456                 /* Setup consumer subdir if none present in the control URI */
 457                 if (strlen(dst_uri->subdir) == 0) {
 458                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 459                                         hostname, obj->subdir);
 460                 } else {
 461                         ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 462                                         hostname, dst_uri->subdir);
 463                 }
 464                 if (ret < 0) {
 465                         PERROR("snprintf set consumer uri subdir");
 466                         goto error;
 467                 }
 468
 469                 strncpy(obj->subdir, tmp_path, sizeof(obj->subdir));
 470                 DBG3("Consumer set network uri subdir path %s", tmp_path);
 471         }
 472
 473         return 0;
 474 equal:
 475         return 1;
 476 error:
 477         return -1;
 478 }
 479
 480 /*
 481  * Send file descriptor to consumer via sock.
 482  */
 483 int consumer_send_fds(struct consumer_socket *sock, int *fds, size_t nb_fd)
 484 {
 485         int ret;
 486
 487         assert(fds);
 488         assert(sock);
 489         assert(nb_fd > 0);
 490
 491         ret = lttcomm_send_fds_unix_sock(sock->fd, fds, nb_fd);
 492         if (ret < 0) {
 493                 PERROR("send consumer fds");
 494                 goto error;
 495         }
 496
 497         ret = consumer_recv_status_reply(sock);
 498
 499 error:
 500         return ret;
 501 }
 502
 503 /*
 504  * Consumer send channel communication message structure to consumer.
 505  */
 506 int consumer_send_channel(struct consumer_socket *sock,
 507                 struct lttcomm_consumer_msg *msg)
 508 {
 509         int ret;
 510
 511         assert(msg);
 512         assert(sock);
 513         assert(sock->fd >= 0);
 514
 515         ret = lttcomm_send_unix_sock(sock->fd, msg,
 516                         sizeof(struct lttcomm_consumer_msg));
 517         if (ret < 0) {
 518                 PERROR("send consumer channel");
 519                 goto error;
 520         }
 521
 522         ret = consumer_recv_status_reply(sock);
 523
 524 error:
 525         return ret;
 526 }
 527
 528 /*
 529  * Init channel communication message structure.
 530  */
 531 void consumer_init_channel_comm_msg(struct lttcomm_consumer_msg *msg,
 532                 enum lttng_consumer_command cmd,
 533                 int channel_key,
 534                 uint64_t max_sb_size,
 535                 uint64_t mmap_len,
 536                 const char *name,
 537                 unsigned int nb_init_streams)
 538 {
 539         assert(msg);
 540
 541         /* TODO: Args validation */
 542
 543         /* Zeroed structure */
 544         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 545
 546         /* Send channel */
 547         msg->cmd_type = cmd;
 548         msg->u.channel.channel_key = channel_key;
 549         msg->u.channel.max_sb_size = max_sb_size;
 550         msg->u.channel.mmap_len = mmap_len;
 551         msg->u.channel.nb_init_streams = nb_init_streams;
 552 }
 553
 554 /*
 555  * Init stream communication message structure.
 556  */
 557 void consumer_init_stream_comm_msg(struct lttcomm_consumer_msg *msg,
 558                 enum lttng_consumer_command cmd,
 559                 int channel_key,
 560                 int stream_key,
 561                 uint32_t state,
 562                 enum lttng_event_output output,
 563                 uint64_t mmap_len,
 564                 uid_t uid,
 565                 gid_t gid,
 566                 int net_index,
 567                 unsigned int metadata_flag,
 568                 const char *name,
 569                 const char *pathname,
 570                 unsigned int session_id)
 571 {
 572         assert(msg);
 573
 574         memset(msg, 0, sizeof(struct lttcomm_consumer_msg));
 575
 576         /* TODO: Args validation */
 577
 578         msg->cmd_type = cmd;
 579         msg->u.stream.channel_key = channel_key;
 580         msg->u.stream.stream_key = stream_key;
 581         msg->u.stream.state = state;
 582         msg->u.stream.output = output;
 583         msg->u.stream.mmap_len = mmap_len;
 584         msg->u.stream.uid = uid;
 585         msg->u.stream.gid = gid;
 586         msg->u.stream.net_index = net_index;
 587         msg->u.stream.metadata_flag = metadata_flag;
 588         msg->u.stream.session_id = (uint64_t) session_id;
 589         strncpy(msg->u.stream.name, name, sizeof(msg->u.stream.name));
 590         msg->u.stream.name[sizeof(msg->u.stream.name) - 1] = '\0';
 591         strncpy(msg->u.stream.path_name, pathname,
 592                         sizeof(msg->u.stream.path_name));
 593         msg->u.stream.path_name[sizeof(msg->u.stream.path_name) - 1] = '\0';
 594 }
 595
 596 /*
 597  * Send stream communication structure to the consumer.
 598  */
 599 int consumer_send_stream(struct consumer_socket *sock,
 600                 struct consumer_output *dst, struct lttcomm_consumer_msg *msg,
 601                 int *fds, size_t nb_fd)
 602 {
 603         int ret;
 604
 605         assert(msg);
 606         assert(dst);
 607         assert(sock);
 608
 609         switch (dst->type) {
 610         case CONSUMER_DST_NET:
 611                 /* Consumer should send the stream on the network. */
 612                 msg->u.stream.net_index = dst->net_seq_index;
 613                 break;
 614         case CONSUMER_DST_LOCAL:
 615                 /* Add stream file name to stream path */
 616                 strncat(msg->u.stream.path_name, "/",
 617                                 sizeof(msg->u.stream.path_name) -
 618                                 strlen(msg->u.stream.path_name) - 1);
 619                 strncat(msg->u.stream.path_name, msg->u.stream.name,
 620                                 sizeof(msg->u.stream.path_name) -
 621                                 strlen(msg->u.stream.path_name) - 1);
 622                 msg->u.stream.path_name[sizeof(msg->u.stream.path_name) - 1] = '\0';
 623                 /* Indicate that the stream is NOT network */
 624                 msg->u.stream.net_index = -1;
 625                 break;
 626         default:
 627                 ERR("Consumer unknown output type (%d)", dst->type);
 628                 ret = -1;
 629                 goto error;
 630         }
 631
 632         /* Send on socket */
 633         ret = lttcomm_send_unix_sock(sock->fd, msg,
 634                         sizeof(struct lttcomm_consumer_msg));
 635         if (ret < 0) {
 636                 PERROR("send consumer stream");
 637                 goto error;
 638         }
 639
 640         ret = consumer_recv_status_reply(sock);
 641         if (ret < 0) {
 642                 goto error;
 643         }
 644
 645         ret = consumer_send_fds(sock, fds, nb_fd);
 646         if (ret < 0) {
 647                 goto error;
 648         }
 649
 650 error:
 651         return ret;
 652 }
 653
 654 /*
 655  * Send relayd socket to consumer associated with a session name.
 656  *
 657  * On success return positive value. On error, negative value.
 658  */
 659 int consumer_send_relayd_socket(struct consumer_socket *consumer_sock,
 660                 struct lttcomm_sock *sock, struct consumer_output *consumer,
 661                 enum lttng_stream_type type)
 662 {
 663         int ret;
 664         struct lttcomm_consumer_msg msg;
 665
 666         /* Code flow error. Safety net. */
 667         assert(sock);
 668         assert(consumer);
 669         assert(consumer_sock);
 670
 671         /* Bail out if consumer is disabled */
 672         if (!consumer->enabled) {
 673                 ret = LTTNG_OK;
 674                 goto error;
 675         }
 676
 677         msg.cmd_type = LTTNG_CONSUMER_ADD_RELAYD_SOCKET;
 678         /*
 679          * Assign network consumer output index using the temporary consumer since
 680          * this call should only be made from within a set_consumer_uri() function
 681          * call in the session daemon.
 682          */
 683         msg.u.relayd_sock.net_index = consumer->net_seq_index;
 684         msg.u.relayd_sock.type = type;
 685         memcpy(&msg.u.relayd_sock.sock, sock, sizeof(msg.u.relayd_sock.sock));
 686
 687         DBG3("Sending relayd sock info to consumer on %d", consumer_sock->fd);
 688         ret = lttcomm_send_unix_sock(consumer_sock->fd, &msg, sizeof(msg));
 689         if (ret < 0) {
 690                 PERROR("send consumer relayd socket info");
 691                 goto error;
 692         }
 693
 694         ret = consumer_recv_status_reply(consumer_sock);
 695         if (ret < 0) {
 696                 goto error;
 697         }
 698
 699         DBG3("Sending relayd socket file descriptor to consumer");
 700         ret = consumer_send_fds(consumer_sock, &sock->fd, 1);
 701         if (ret < 0) {
 702                 goto error;
 703         }
 704
 705         DBG2("Consumer relayd socket sent");
 706
 707 error:
 708         return ret;
 709 }
 710
 711 /*
 712  * Set consumer subdirectory using the session name and a generated datetime if
 713  * needed. This is appended to the current subdirectory.
 714  */
 715 int consumer_set_subdir(struct consumer_output *consumer,
 716                 const char *session_name)
 717 {
 718         int ret = 0;
 719         unsigned int have_default_name = 0;
 720         char datetime[16], tmp_path[PATH_MAX];
 721         time_t rawtime;
 722         struct tm *timeinfo;
 723
 724         assert(consumer);
 725         assert(session_name);
 726
 727         memset(tmp_path, 0, sizeof(tmp_path));
 728
 729         /* Flag if we have a default session. */
 730         if (strncmp(session_name, DEFAULT_SESSION_NAME "-",
 731                                 strlen(DEFAULT_SESSION_NAME) + 1) == 0) {
 732                 have_default_name = 1;
 733         } else {
 734                 /* Get date and time for session path */
 735                 time(&rawtime);
 736                 timeinfo = localtime(&rawtime);
 737                 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
 738         }
 739
 740         if (have_default_name) {
 741                 ret = snprintf(tmp_path, sizeof(tmp_path),
 742                                 "%s/%s", consumer->subdir, session_name);
 743         } else {
 744                 ret = snprintf(tmp_path, sizeof(tmp_path),
 745                                 "%s/%s-%s/", consumer->subdir, session_name, datetime);
 746         }
 747         if (ret < 0) {
 748                 PERROR("snprintf session name date");
 749                 goto error;
 750         }
 751
 752         strncpy(consumer->subdir, tmp_path, sizeof(consumer->subdir));
 753         DBG2("Consumer subdir set to %s", consumer->subdir);
 754
 755 error:
 756         return ret;
 757 }
 758
 759 /*
 760  * Ask the consumer if the data is ready to read (NOT pending) for the specific
 761  * session id.
 762  *
 763  * This function has a different behavior with the consumer i.e. that it waits
 764  * for a reply from the consumer if yes or no the data is pending.
 765  */
 766 int consumer_is_data_pending(unsigned int id,
 767                 struct consumer_output *consumer)
 768 {
 769         int ret;
 770         int32_t ret_code = 0;  /* Default is that the data is NOT pending */
 771         struct consumer_socket *socket;
 772         struct lttng_ht_iter iter;
 773         struct lttcomm_consumer_msg msg;
 774
 775         assert(consumer);
 776
 777         msg.cmd_type = LTTNG_CONSUMER_DATA_PENDING;
 778
 779         msg.u.data_pending.session_id = (uint64_t) id;
 780
 781         DBG3("Consumer data pending for id %u", id);
 782
 783         /* Send command for each consumer */
 784         cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
 785                         node.node) {
 786                 /* Code flow error */
 787                 assert(socket->fd >= 0);
 788
 789                 pthread_mutex_lock(socket->lock);
 790
 791                 ret = lttcomm_send_unix_sock(socket->fd, &msg, sizeof(msg));
 792                 if (ret < 0) {
 793                         PERROR("send consumer data pending command");
 794                         pthread_mutex_unlock(socket->lock);
 795                         goto error;
 796                 }
 797
 798                 /*
 799                  * No need for a recv reply status because the answer to the command is
 800                  * the reply status message.
 801                  */
 802
 803                 ret = lttcomm_recv_unix_sock(socket->fd, &ret_code, sizeof(ret_code));
 804                 if (ret < 0) {
 805                         PERROR("recv consumer data pending status");
 806                         pthread_mutex_unlock(socket->lock);
 807                         goto error;
 808                 }
 809
 810                 pthread_mutex_unlock(socket->lock);
 811
 812                 if (ret_code == 1) {
 813                         break;
 814                 }
 815         }
 816
 817         DBG("Consumer data pending ret %d", ret_code);
 818         return ret_code;
 819
 820 error:
 821         return -1;
 822 }