src/common/relayd/relayd.c

   1 /*
   2  * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _LGPL_SOURCE
  19 #include <assert.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <sys/stat.h>
  24 #include <inttypes.h>
  25
  26 #include <common/common.h>
  27 #include <common/defaults.h>
  28 #include <common/compat/endian.h>
  29 #include <common/sessiond-comm/relayd.h>
  30 #include <common/index/ctf-index.h>
  31
  32 #include "relayd.h"
  33
  34 /*
  35  * Send command. Fill up the header and append the data.
  36  */
  37 static int send_command(struct lttcomm_relayd_sock *rsock,
  38                 enum lttcomm_relayd_command cmd, const void *data, size_t size,
  39                 int flags)
  40 {
  41         int ret;
  42         struct lttcomm_relayd_hdr header;
  43         char *buf;
  44         uint64_t buf_size = sizeof(header);
  45
  46         if (rsock->sock.fd < 0) {
  47                 return -ECONNRESET;
  48         }
  49
  50         if (data) {
  51                 buf_size += size;
  52         }
  53
  54         buf = zmalloc(buf_size);
  55         if (buf == NULL) {
  56                 PERROR("zmalloc relayd send command buf");
  57                 ret = -1;
  58                 goto alloc_error;
  59         }
  60
  61         memset(&header, 0, sizeof(header));
  62         header.cmd = htobe32(cmd);
  63         header.data_size = htobe64(size);
  64
  65         /* Zeroed for now since not used. */
  66         header.cmd_version = 0;
  67         header.circuit_id = 0;
  68
  69         /* Prepare buffer to send. */
  70         memcpy(buf, &header, sizeof(header));
  71         if (data) {
  72                 memcpy(buf + sizeof(header), data, size);
  73         }
  74
  75         DBG3("Relayd sending command %d of size %" PRIu64, (int) cmd, buf_size);
  76         ret = rsock->sock.ops->sendmsg(&rsock->sock, buf, buf_size, flags);
  77         if (ret < 0) {
  78                 PERROR("Failed to send command %d of size %" PRIu64,
  79                                 (int) cmd, buf_size);
  80                 ret = -errno;
  81                 goto error;
  82         }
  83 error:
  84         free(buf);
  85 alloc_error:
  86         return ret;
  87 }
  88
  89 /*
  90  * Receive reply data on socket. This MUST be call after send_command or else
  91  * could result in unexpected behavior(s).
  92  */
  93 static int recv_reply(struct lttcomm_relayd_sock *rsock, void *data, size_t size)
  94 {
  95         int ret;
  96
  97         if (rsock->sock.fd < 0) {
  98                 return -ECONNRESET;
  99         }
 100
 101         DBG3("Relayd waiting for reply of size %zu", size);
 102
 103         ret = rsock->sock.ops->recvmsg(&rsock->sock, data, size, 0);
 104         if (ret <= 0 || ret != size) {
 105                 if (ret == 0) {
 106                         /* Orderly shutdown. */
 107                         DBG("Socket %d has performed an orderly shutdown", rsock->sock.fd);
 108                 } else {
 109                         DBG("Receiving reply failed on sock %d for size %zu with ret %d",
 110                                         rsock->sock.fd, size, ret);
 111                 }
 112                 /* Always return -1 here and the caller can use errno. */
 113                 ret = -1;
 114                 goto error;
 115         }
 116
 117 error:
 118         return ret;
 119 }
 120
 121 /*
 122  * Starting at 2.4, RELAYD_CREATE_SESSION takes additional parameters to
 123  * support the live reading capability.
 124  */
 125 static int relayd_create_session_2_4(struct lttcomm_relayd_sock *rsock,
 126                 char *session_name, char *hostname, int session_live_timer,
 127                 unsigned int snapshot)
 128 {
 129         int ret;
 130         struct lttcomm_relayd_create_session_2_4 msg;
 131
 132         if (lttng_strncpy(msg.session_name, session_name,
 133                         sizeof(msg.session_name))) {
 134                 ret = -1;
 135                 goto error;
 136         }
 137         if (lttng_strncpy(msg.hostname, hostname, sizeof(msg.hostname))) {
 138                 ret = -1;
 139                 goto error;
 140         }
 141         msg.live_timer = htobe32(session_live_timer);
 142         msg.snapshot = htobe32(snapshot);
 143
 144         /* Send command */
 145         ret = send_command(rsock, RELAYD_CREATE_SESSION, &msg, sizeof(msg), 0);
 146         if (ret < 0) {
 147                 goto error;
 148         }
 149
 150 error:
 151         return ret;
 152 }
 153
 154 /*
 155  * RELAYD_CREATE_SESSION from 2.1 to 2.3.
 156  */
 157 static int relayd_create_session_2_1(struct lttcomm_relayd_sock *rsock)
 158 {
 159         int ret;
 160
 161         /* Send command */
 162         ret = send_command(rsock, RELAYD_CREATE_SESSION, NULL, 0, 0);
 163         if (ret < 0) {
 164                 goto error;
 165         }
 166
 167 error:
 168         return ret;
 169 }
 170
 171 /*
 172  * Send a RELAYD_CREATE_SESSION command to the relayd with the given socket and
 173  * set session_id of the relayd if we have a successful reply from the relayd.
 174  *
 175  * On success, return 0 else a negative value which is either an errno error or
 176  * a lttng error code from the relayd.
 177  */
 178 int relayd_create_session(struct lttcomm_relayd_sock *rsock, uint64_t *session_id,
 179                 char *session_name, char *hostname, int session_live_timer,
 180                 unsigned int snapshot)
 181 {
 182         int ret;
 183         struct lttcomm_relayd_status_session reply;
 184
 185         assert(rsock);
 186         assert(session_id);
 187
 188         DBG("Relayd create session");
 189
 190         switch(rsock->minor) {
 191                 case 1:
 192                 case 2:
 193                 case 3:
 194                         ret = relayd_create_session_2_1(rsock);
 195                         break;
 196                 case 4:
 197                 default:
 198                         ret = relayd_create_session_2_4(rsock, session_name,
 199                                         hostname, session_live_timer, snapshot);
 200                         break;
 201         }
 202
 203         if (ret < 0) {
 204                 goto error;
 205         }
 206
 207         /* Receive response */
 208         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 209         if (ret < 0) {
 210                 goto error;
 211         }
 212
 213         reply.session_id = be64toh(reply.session_id);
 214         reply.ret_code = be32toh(reply.ret_code);
 215
 216         /* Return session id or negative ret code. */
 217         if (reply.ret_code != LTTNG_OK) {
 218                 ret = -1;
 219                 ERR("Relayd create session replied error %d", reply.ret_code);
 220                 goto error;
 221         } else {
 222                 ret = 0;
 223                 *session_id = reply.session_id;
 224         }
 225
 226         DBG("Relayd session created with id %" PRIu64, reply.session_id);
 227
 228 error:
 229         return ret;
 230 }
 231
 232 /*
 233  * Add stream on the relayd and assign stream handle to the stream_id argument.
 234  *
 235  * On success return 0 else return ret_code negative value.
 236  */
 237 int relayd_add_stream(struct lttcomm_relayd_sock *rsock, const char *channel_name,
 238                 const char *pathname, uint64_t *stream_id,
 239                 uint64_t tracefile_size, uint64_t tracefile_count)
 240 {
 241         int ret;
 242         struct lttcomm_relayd_add_stream msg;
 243         struct lttcomm_relayd_add_stream_2_2 msg_2_2;
 244         struct lttcomm_relayd_status_stream reply;
 245
 246         /* Code flow error. Safety net. */
 247         assert(rsock);
 248         assert(channel_name);
 249         assert(pathname);
 250
 251         DBG("Relayd adding stream for channel name %s", channel_name);
 252
 253         /* Compat with relayd 2.1 */
 254         if (rsock->minor == 1) {
 255                 memset(&msg, 0, sizeof(msg));
 256                 if (lttng_strncpy(msg.channel_name, channel_name,
 257                                 sizeof(msg.channel_name))) {
 258                         ret = -1;
 259                         goto error;
 260                 }
 261                 if (lttng_strncpy(msg.pathname, pathname,
 262                                 sizeof(msg.pathname))) {
 263                         ret = -1;
 264                         goto error;
 265                 }
 266
 267                 /* Send command */
 268                 ret = send_command(rsock, RELAYD_ADD_STREAM, (void *) &msg, sizeof(msg), 0);
 269                 if (ret < 0) {
 270                         goto error;
 271                 }
 272         } else {
 273                 memset(&msg_2_2, 0, sizeof(msg_2_2));
 274                 /* Compat with relayd 2.2+ */
 275                 if (lttng_strncpy(msg_2_2.channel_name, channel_name,
 276                                 sizeof(msg_2_2.channel_name))) {
 277                         ret = -1;
 278                         goto error;
 279                 }
 280                 if (lttng_strncpy(msg_2_2.pathname, pathname,
 281                                 sizeof(msg_2_2.pathname))) {
 282                         ret = -1;
 283                         goto error;
 284                 }
 285                 msg_2_2.tracefile_size = htobe64(tracefile_size);
 286                 msg_2_2.tracefile_count = htobe64(tracefile_count);
 287
 288                 /* Send command */
 289                 ret = send_command(rsock, RELAYD_ADD_STREAM, (void *) &msg_2_2, sizeof(msg_2_2), 0);
 290                 if (ret < 0) {
 291                         goto error;
 292                 }
 293         }
 294
 295         /* Waiting for reply */
 296         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 297         if (ret < 0) {
 298                 goto error;
 299         }
 300
 301         /* Back to host bytes order. */
 302         reply.handle = be64toh(reply.handle);
 303         reply.ret_code = be32toh(reply.ret_code);
 304
 305         /* Return session id or negative ret code. */
 306         if (reply.ret_code != LTTNG_OK) {
 307                 ret = -1;
 308                 ERR("Relayd add stream replied error %d", reply.ret_code);
 309         } else {
 310                 /* Success */
 311                 ret = 0;
 312                 *stream_id = reply.handle;
 313         }
 314
 315         DBG("Relayd stream added successfully with handle %" PRIu64,
 316                 reply.handle);
 317
 318 error:
 319         return ret;
 320 }
 321
 322 /*
 323  * Inform the relay that all the streams for the current channel has been sent.
 324  *
 325  * On success return 0 else return ret_code negative value.
 326  */
 327 int relayd_streams_sent(struct lttcomm_relayd_sock *rsock)
 328 {
 329         int ret;
 330         struct lttcomm_relayd_generic_reply reply;
 331
 332         /* Code flow error. Safety net. */
 333         assert(rsock);
 334
 335         DBG("Relayd sending streams sent.");
 336
 337         /* This feature was introduced in 2.4, ignore it for earlier versions. */
 338         if (rsock->minor < 4) {
 339                 ret = 0;
 340                 goto end;
 341         }
 342
 343         /* Send command */
 344         ret = send_command(rsock, RELAYD_STREAMS_SENT, NULL, 0, 0);
 345         if (ret < 0) {
 346                 goto error;
 347         }
 348
 349         /* Waiting for reply */
 350         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 351         if (ret < 0) {
 352                 goto error;
 353         }
 354
 355         /* Back to host bytes order. */
 356         reply.ret_code = be32toh(reply.ret_code);
 357
 358         /* Return session id or negative ret code. */
 359         if (reply.ret_code != LTTNG_OK) {
 360                 ret = -1;
 361                 ERR("Relayd streams sent replied error %d", reply.ret_code);
 362                 goto error;
 363         } else {
 364                 /* Success */
 365                 ret = 0;
 366         }
 367
 368         DBG("Relayd streams sent success");
 369
 370 error:
 371 end:
 372         return ret;
 373 }
 374
 375 /*
 376  * Check version numbers on the relayd.
 377  * If major versions are compatible, we assign minor_to_use to the
 378  * minor version of the procotol we are going to use for this session.
 379  *
 380  * Return 0 if the two daemons are compatible, LTTNG_ERR_RELAYD_VERSION_FAIL
 381  * otherwise, or a negative value on network errors.
 382  */
 383 int relayd_version_check(struct lttcomm_relayd_sock *rsock)
 384 {
 385         int ret;
 386         struct lttcomm_relayd_version msg;
 387
 388         /* Code flow error. Safety net. */
 389         assert(rsock);
 390
 391         DBG("Relayd version check for major.minor %u.%u", rsock->major,
 392                         rsock->minor);
 393
 394         memset(&msg, 0, sizeof(msg));
 395         /* Prepare network byte order before transmission. */
 396         msg.major = htobe32(rsock->major);
 397         msg.minor = htobe32(rsock->minor);
 398
 399         /* Send command */
 400         ret = send_command(rsock, RELAYD_VERSION, (void *) &msg, sizeof(msg), 0);
 401         if (ret < 0) {
 402                 goto error;
 403         }
 404
 405         /* Receive response */
 406         ret = recv_reply(rsock, (void *) &msg, sizeof(msg));
 407         if (ret < 0) {
 408                 goto error;
 409         }
 410
 411         /* Set back to host bytes order */
 412         msg.major = be32toh(msg.major);
 413         msg.minor = be32toh(msg.minor);
 414
 415         /*
 416          * Only validate the major version. If the other side is higher,
 417          * communication is not possible. Only major version equal can talk to each
 418          * other. If the minor version differs, the lowest version is used by both
 419          * sides.
 420          */
 421         if (msg.major != rsock->major) {
 422                 /* Not compatible */
 423                 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
 424                 DBG2("Relayd version is NOT compatible. Relayd version %u != %u (us)",
 425                                 msg.major, rsock->major);
 426                 goto error;
 427         }
 428
 429         /*
 430          * If the relayd's minor version is higher, it will adapt to our version so
 431          * we can continue to use the latest relayd communication data structure.
 432          * If the received minor version is higher, the relayd should adapt to us.
 433          */
 434         if (rsock->minor > msg.minor) {
 435                 rsock->minor = msg.minor;
 436         }
 437
 438         /* Version number compatible */
 439         DBG2("Relayd version is compatible, using protocol version %u.%u",
 440                         rsock->major, rsock->minor);
 441         ret = 0;
 442
 443 error:
 444         return ret;
 445 }
 446
 447 /*
 448  * Add stream on the relayd and assign stream handle to the stream_id argument.
 449  *
 450  * On success return 0 else return ret_code negative value.
 451  */
 452 int relayd_send_metadata(struct lttcomm_relayd_sock *rsock, size_t len)
 453 {
 454         int ret;
 455
 456         /* Code flow error. Safety net. */
 457         assert(rsock);
 458
 459         DBG("Relayd sending metadata of size %zu", len);
 460
 461         /* Send command */
 462         ret = send_command(rsock, RELAYD_SEND_METADATA, NULL, len, 0);
 463         if (ret < 0) {
 464                 goto error;
 465         }
 466
 467         DBG2("Relayd metadata added successfully");
 468
 469         /*
 470          * After that call, the metadata data MUST be sent to the relayd so the
 471          * receive size on the other end matches the len of the metadata packet
 472          * header. This is why we don't wait for a reply here.
 473          */
 474
 475 error:
 476         return ret;
 477 }
 478
 479 /*
 480  * Connect to relay daemon with an allocated lttcomm_relayd_sock.
 481  */
 482 int relayd_connect(struct lttcomm_relayd_sock *rsock)
 483 {
 484         /* Code flow error. Safety net. */
 485         assert(rsock);
 486
 487         if (!rsock->sock.ops) {
 488                 /*
 489                  * Attempting a connect on a non-initialized socket.
 490                  */
 491                 return -ECONNRESET;
 492         }
 493
 494         DBG3("Relayd connect ...");
 495
 496         return rsock->sock.ops->connect(&rsock->sock);
 497 }
 498
 499 /*
 500  * Close relayd socket with an allocated lttcomm_relayd_sock.
 501  *
 502  * If no socket operations are found, simply return 0 meaning that everything
 503  * is fine. Without operations, the socket can not possibly be opened or used.
 504  * This is possible if the socket was allocated but not created. However, the
 505  * caller could simply use it to store a valid file descriptor for instance
 506  * passed over a Unix socket and call this to cleanup but still without a valid
 507  * ops pointer.
 508  *
 509  * Return the close returned value. On error, a negative value is usually
 510  * returned back from close(2).
 511  */
 512 int relayd_close(struct lttcomm_relayd_sock *rsock)
 513 {
 514         int ret;
 515
 516         /* Code flow error. Safety net. */
 517         assert(rsock);
 518
 519         /* An invalid fd is fine, return success. */
 520         if (rsock->sock.fd < 0) {
 521                 ret = 0;
 522                 goto end;
 523         }
 524
 525         DBG3("Relayd closing socket %d", rsock->sock.fd);
 526
 527         if (rsock->sock.ops) {
 528                 ret = rsock->sock.ops->close(&rsock->sock);
 529         } else {
 530                 /* Default call if no specific ops found. */
 531                 ret = close(rsock->sock.fd);
 532                 if (ret < 0) {
 533                         PERROR("relayd_close default close");
 534                 }
 535         }
 536         rsock->sock.fd = -1;
 537
 538 end:
 539         return ret;
 540 }
 541
 542 /*
 543  * Send data header structure to the relayd.
 544  */
 545 int relayd_send_data_hdr(struct lttcomm_relayd_sock *rsock,
 546                 struct lttcomm_relayd_data_hdr *hdr, size_t size)
 547 {
 548         int ret;
 549
 550         /* Code flow error. Safety net. */
 551         assert(rsock);
 552         assert(hdr);
 553
 554         if (rsock->sock.fd < 0) {
 555                 return -ECONNRESET;
 556         }
 557
 558         DBG3("Relayd sending data header of size %zu", size);
 559
 560         /* Again, safety net */
 561         if (size == 0) {
 562                 size = sizeof(struct lttcomm_relayd_data_hdr);
 563         }
 564
 565         /* Only send data header. */
 566         ret = rsock->sock.ops->sendmsg(&rsock->sock, hdr, size, 0);
 567         if (ret < 0) {
 568                 ret = -errno;
 569                 goto error;
 570         }
 571
 572         /*
 573          * The data MUST be sent right after that command for the receive on the
 574          * other end to match the size in the header.
 575          */
 576
 577 error:
 578         return ret;
 579 }
 580
 581 /*
 582  * Send close stream command to the relayd.
 583  */
 584 int relayd_send_close_stream(struct lttcomm_relayd_sock *rsock, uint64_t stream_id,
 585                 uint64_t last_net_seq_num)
 586 {
 587         int ret;
 588         struct lttcomm_relayd_close_stream msg;
 589         struct lttcomm_relayd_generic_reply reply;
 590
 591         /* Code flow error. Safety net. */
 592         assert(rsock);
 593
 594         DBG("Relayd closing stream id %" PRIu64, stream_id);
 595
 596         memset(&msg, 0, sizeof(msg));
 597         msg.stream_id = htobe64(stream_id);
 598         msg.last_net_seq_num = htobe64(last_net_seq_num);
 599
 600         /* Send command */
 601         ret = send_command(rsock, RELAYD_CLOSE_STREAM, (void *) &msg, sizeof(msg), 0);
 602         if (ret < 0) {
 603                 goto error;
 604         }
 605
 606         /* Receive response */
 607         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 608         if (ret < 0) {
 609                 goto error;
 610         }
 611
 612         reply.ret_code = be32toh(reply.ret_code);
 613
 614         /* Return session id or negative ret code. */
 615         if (reply.ret_code != LTTNG_OK) {
 616                 ret = -1;
 617                 ERR("Relayd close stream replied error %d", reply.ret_code);
 618         } else {
 619                 /* Success */
 620                 ret = 0;
 621         }
 622
 623         DBG("Relayd close stream id %" PRIu64 " successfully", stream_id);
 624
 625 error:
 626         return ret;
 627 }
 628
 629 /*
 630  * Check for data availability for a given stream id.
 631  *
 632  * Return 0 if NOT pending, 1 if so and a negative value on error.
 633  */
 634 int relayd_data_pending(struct lttcomm_relayd_sock *rsock, uint64_t stream_id,
 635                 uint64_t last_net_seq_num)
 636 {
 637         int ret;
 638         struct lttcomm_relayd_data_pending msg;
 639         struct lttcomm_relayd_generic_reply reply;
 640
 641         /* Code flow error. Safety net. */
 642         assert(rsock);
 643
 644         DBG("Relayd data pending for stream id %" PRIu64, stream_id);
 645
 646         memset(&msg, 0, sizeof(msg));
 647         msg.stream_id = htobe64(stream_id);
 648         msg.last_net_seq_num = htobe64(last_net_seq_num);
 649
 650         /* Send command */
 651         ret = send_command(rsock, RELAYD_DATA_PENDING, (void *) &msg,
 652                         sizeof(msg), 0);
 653         if (ret < 0) {
 654                 goto error;
 655         }
 656
 657         /* Receive response */
 658         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 659         if (ret < 0) {
 660                 goto error;
 661         }
 662
 663         reply.ret_code = be32toh(reply.ret_code);
 664
 665         /* Return session id or negative ret code. */
 666         if (reply.ret_code >= LTTNG_OK) {
 667                 ERR("Relayd data pending replied error %d", reply.ret_code);
 668         }
 669
 670         /* At this point, the ret code is either 1 or 0 */
 671         ret = reply.ret_code;
 672
 673         DBG("Relayd data is %s pending for stream id %" PRIu64,
 674                         ret == 1 ? "" : "NOT", stream_id);
 675
 676 error:
 677         return ret;
 678 }
 679
 680 /*
 681  * Check on the relayd side for a quiescent state on the control socket.
 682  */
 683 int relayd_quiescent_control(struct lttcomm_relayd_sock *rsock,
 684                 uint64_t metadata_stream_id)
 685 {
 686         int ret;
 687         struct lttcomm_relayd_quiescent_control msg;
 688         struct lttcomm_relayd_generic_reply reply;
 689
 690         /* Code flow error. Safety net. */
 691         assert(rsock);
 692
 693         DBG("Relayd checking quiescent control state");
 694
 695         memset(&msg, 0, sizeof(msg));
 696         msg.stream_id = htobe64(metadata_stream_id);
 697
 698         /* Send command */
 699         ret = send_command(rsock, RELAYD_QUIESCENT_CONTROL, &msg, sizeof(msg), 0);
 700         if (ret < 0) {
 701                 goto error;
 702         }
 703
 704         /* Receive response */
 705         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 706         if (ret < 0) {
 707                 goto error;
 708         }
 709
 710         reply.ret_code = be32toh(reply.ret_code);
 711
 712         /* Return session id or negative ret code. */
 713         if (reply.ret_code != LTTNG_OK) {
 714                 ret = -1;
 715                 ERR("Relayd quiescent control replied error %d", reply.ret_code);
 716                 goto error;
 717         }
 718
 719         /* Control socket is quiescent */
 720         return 0;
 721
 722 error:
 723         return ret;
 724 }
 725
 726 /*
 727  * Begin a data pending command for a specific session id.
 728  */
 729 int relayd_begin_data_pending(struct lttcomm_relayd_sock *rsock, uint64_t id)
 730 {
 731         int ret;
 732         struct lttcomm_relayd_begin_data_pending msg;
 733         struct lttcomm_relayd_generic_reply reply;
 734
 735         /* Code flow error. Safety net. */
 736         assert(rsock);
 737
 738         DBG("Relayd begin data pending");
 739
 740         memset(&msg, 0, sizeof(msg));
 741         msg.session_id = htobe64(id);
 742
 743         /* Send command */
 744         ret = send_command(rsock, RELAYD_BEGIN_DATA_PENDING, &msg, sizeof(msg), 0);
 745         if (ret < 0) {
 746                 goto error;
 747         }
 748
 749         /* Receive response */
 750         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 751         if (ret < 0) {
 752                 goto error;
 753         }
 754
 755         reply.ret_code = be32toh(reply.ret_code);
 756
 757         /* Return session id or negative ret code. */
 758         if (reply.ret_code != LTTNG_OK) {
 759                 ret = -1;
 760                 ERR("Relayd begin data pending replied error %d", reply.ret_code);
 761                 goto error;
 762         }
 763
 764         return 0;
 765
 766 error:
 767         return ret;
 768 }
 769
 770 /*
 771  * End a data pending command for a specific session id.
 772  *
 773  * Return 0 on success and set is_data_inflight to 0 if no data is being
 774  * streamed or 1 if it is the case.
 775  */
 776 int relayd_end_data_pending(struct lttcomm_relayd_sock *rsock, uint64_t id,
 777                 unsigned int *is_data_inflight)
 778 {
 779         int ret, recv_ret;
 780         struct lttcomm_relayd_end_data_pending msg;
 781         struct lttcomm_relayd_generic_reply reply;
 782
 783         /* Code flow error. Safety net. */
 784         assert(rsock);
 785
 786         DBG("Relayd end data pending");
 787
 788         memset(&msg, 0, sizeof(msg));
 789         msg.session_id = htobe64(id);
 790
 791         /* Send command */
 792         ret = send_command(rsock, RELAYD_END_DATA_PENDING, &msg, sizeof(msg), 0);
 793         if (ret < 0) {
 794                 goto error;
 795         }
 796
 797         /* Receive response */
 798         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 799         if (ret < 0) {
 800                 goto error;
 801         }
 802
 803         recv_ret = be32toh(reply.ret_code);
 804         if (recv_ret < 0) {
 805                 ret = recv_ret;
 806                 goto error;
 807         }
 808
 809         *is_data_inflight = recv_ret;
 810
 811         DBG("Relayd end data pending is data inflight: %d", recv_ret);
 812
 813         return 0;
 814
 815 error:
 816         return ret;
 817 }
 818
 819 /*
 820  * Send index to the relayd.
 821  */
 822 int relayd_send_index(struct lttcomm_relayd_sock *rsock,
 823                 struct ctf_packet_index *index, uint64_t relay_stream_id,
 824                 uint64_t net_seq_num)
 825 {
 826         int ret;
 827         struct lttcomm_relayd_index msg;
 828         struct lttcomm_relayd_generic_reply reply;
 829
 830         /* Code flow error. Safety net. */
 831         assert(rsock);
 832
 833         if (rsock->minor < 4) {
 834                 DBG("Not sending indexes before protocol 2.4");
 835                 ret = 0;
 836                 goto error;
 837         }
 838
 839         DBG("Relayd sending index for stream ID %" PRIu64, relay_stream_id);
 840
 841         memset(&msg, 0, sizeof(msg));
 842         msg.relay_stream_id = htobe64(relay_stream_id);
 843         msg.net_seq_num = htobe64(net_seq_num);
 844
 845         /* The index is already in big endian. */
 846         msg.packet_size = index->packet_size;
 847         msg.content_size = index->content_size;
 848         msg.timestamp_begin = index->timestamp_begin;
 849         msg.timestamp_end = index->timestamp_end;
 850         msg.events_discarded = index->events_discarded;
 851         msg.stream_id = index->stream_id;
 852
 853         if (rsock->minor >= 8) {
 854                 msg.stream_instance_id = index->stream_instance_id;
 855                 msg.packet_seq_num = index->packet_seq_num;
 856         }
 857
 858         /* Send command */
 859         ret = send_command(rsock, RELAYD_SEND_INDEX, &msg,
 860                 lttcomm_relayd_index_len(lttng_to_index_major(rsock->major,
 861                                                                 rsock->minor),
 862                                 lttng_to_index_minor(rsock->major, rsock->minor)),
 863                                 0);
 864         if (ret < 0) {
 865                 goto error;
 866         }
 867
 868         /* Receive response */
 869         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 870         if (ret < 0) {
 871                 goto error;
 872         }
 873
 874         reply.ret_code = be32toh(reply.ret_code);
 875
 876         /* Return session id or negative ret code. */
 877         if (reply.ret_code != LTTNG_OK) {
 878                 ret = -1;
 879                 ERR("Relayd send index replied error %d", reply.ret_code);
 880         } else {
 881                 /* Success */
 882                 ret = 0;
 883         }
 884
 885 error:
 886         return ret;
 887 }
 888
 889 /*
 890  * Ask the relay to reset the metadata trace file (regeneration).
 891  */
 892 int relayd_reset_metadata(struct lttcomm_relayd_sock *rsock,
 893                 uint64_t stream_id, uint64_t version)
 894 {
 895         int ret;
 896         struct lttcomm_relayd_reset_metadata msg;
 897         struct lttcomm_relayd_generic_reply reply;
 898
 899         /* Code flow error. Safety net. */
 900         assert(rsock);
 901
 902         /* Should have been prevented by the sessiond. */
 903         if (rsock->minor < 8) {
 904                 ERR("Metadata regeneration unsupported before 2.8");
 905                 ret = -1;
 906                 goto error;
 907         }
 908
 909         DBG("Relayd reset metadata stream id %" PRIu64, stream_id);
 910
 911         memset(&msg, 0, sizeof(msg));
 912         msg.stream_id = htobe64(stream_id);
 913         msg.version = htobe64(version);
 914
 915         /* Send command */
 916         ret = send_command(rsock, RELAYD_RESET_METADATA, (void *) &msg, sizeof(msg), 0);
 917         if (ret < 0) {
 918                 goto error;
 919         }
 920
 921         /* Receive response */
 922         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
 923         if (ret < 0) {
 924                 goto error;
 925         }
 926
 927         reply.ret_code = be32toh(reply.ret_code);
 928
 929         /* Return session id or negative ret code. */
 930         if (reply.ret_code != LTTNG_OK) {
 931                 ret = -1;
 932                 ERR("Relayd reset metadata replied error %d", reply.ret_code);
 933         } else {
 934                 /* Success */
 935                 ret = 0;
 936         }
 937
 938         DBG("Relayd reset metadata stream id %" PRIu64 " successfully", stream_id);
 939
 940 error:
 941         return ret;
 942 }
 943
 944 int relayd_rotate_stream(struct lttcomm_relayd_sock *rsock, uint64_t stream_id,
 945                 const char *new_pathname, uint64_t new_chunk_id,
 946                 uint64_t seq_num)
 947 {
 948         int ret;
 949         struct lttcomm_relayd_rotate_stream *msg = NULL;
 950         struct lttcomm_relayd_generic_reply reply;
 951         size_t len;
 952         int msg_len;
 953
 954         /* Code flow error. Safety net. */
 955         assert(rsock);
 956
 957         DBG("Sending rotate stream id %" PRIu64 " command to relayd", stream_id);
 958
 959         /* Account for the trailing NULL. */
 960         len = strnlen(new_pathname, LTTNG_PATH_MAX) + 1;
 961         if (len > LTTNG_PATH_MAX) {
 962                 ERR("Path used in relayd rotate stream command exceeds the maximal allowed length");
 963                 ret = -1;
 964                 goto error;
 965         }
 966
 967         msg_len = offsetof(struct lttcomm_relayd_rotate_stream, new_pathname) + len;
 968         msg = zmalloc(msg_len);
 969         if (!msg) {
 970                 PERROR("Failed to allocate relayd rotate stream command of %d bytes",
 971                                 msg_len);
 972                 ret = -1;
 973                 goto error;
 974         }
 975
 976         if (lttng_strncpy(msg->new_pathname, new_pathname, len)) {
 977                 ret = -1;
 978                 ERR("Failed to copy relayd rotate stream command's new path name");
 979                 goto error;
 980         }
 981
 982         msg->pathname_length = htobe32(len);
 983         msg->stream_id = htobe64(stream_id);
 984         msg->new_chunk_id = htobe64(new_chunk_id);
 985         /*
 986          * The seq_num is invalid for metadata streams, but it is ignored on
 987          * the relay.
 988          */
 989         msg->rotate_at_seq_num = htobe64(seq_num);
 990
 991         /* Send command. */
 992         ret = send_command(rsock, RELAYD_ROTATE_STREAM, (void *) msg, msg_len, 0);
 993         if (ret < 0) {
 994                 ERR("Send rotate command");
 995                 goto error;
 996         }
 997
 998         /* Receive response. */
 999         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
1000         if (ret < 0) {
1001                 ERR("Receive rotate reply");
1002                 goto error;
1003         }
1004
1005         reply.ret_code = be32toh(reply.ret_code);
1006
1007         /* Return session id or negative ret code. */
1008         if (reply.ret_code != LTTNG_OK) {
1009                 ret = -1;
1010                 ERR("Relayd rotate stream replied error %d", reply.ret_code);
1011         } else {
1012                 /* Success. */
1013                 ret = 0;
1014                 DBG("Relayd rotated stream id %" PRIu64 " successfully", stream_id);
1015         }
1016
1017 error:
1018         free(msg);
1019         return ret;
1020 }
1021
1022 int relayd_rotate_rename(struct lttcomm_relayd_sock *rsock,
1023                 const char *old_path, const char *new_path)
1024 {
1025         int ret;
1026         struct lttcomm_relayd_rotate_rename *msg = NULL;
1027         struct lttcomm_relayd_generic_reply reply;
1028         size_t old_path_length, new_path_length;
1029         size_t msg_length;
1030
1031         /* Code flow error. Safety net. */
1032         assert(rsock);
1033
1034         DBG("Relayd rename chunk %s to %s", old_path, new_path);
1035
1036         /* The two paths are sent with a '\0' delimiter between them. */
1037         old_path_length = strlen(old_path) + 1;
1038         new_path_length = strlen(new_path) + 1;
1039
1040         msg_length = sizeof(*msg) + old_path_length + new_path_length;
1041         msg = zmalloc(msg_length);
1042         if (!msg) {
1043                 PERROR("zmalloc rotate-rename command message");
1044                 ret = -1;
1045                 goto error;
1046         }
1047
1048         assert(old_path_length <= UINT32_MAX);
1049         msg->old_path_length = htobe32(old_path_length);
1050
1051         assert(new_path_length <= UINT32_MAX);
1052         msg->new_path_length = htobe32(new_path_length);
1053
1054         strcpy(msg->paths, old_path);
1055         strcpy(msg->paths + old_path_length, new_path);
1056
1057         /* Send command */
1058         ret = send_command(rsock, RELAYD_ROTATE_RENAME, (const void *) msg,
1059                         msg_length, 0);
1060         if (ret < 0) {
1061                 goto error;
1062         }
1063
1064         /* Receive response */
1065         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
1066         if (ret < 0) {
1067                 goto error;
1068         }
1069
1070         reply.ret_code = be32toh(reply.ret_code);
1071
1072         /* Return session id or negative ret code. */
1073         if (reply.ret_code != LTTNG_OK) {
1074                 ret = -1;
1075                 ERR("Relayd rotate rename replied error %d", reply.ret_code);
1076         } else {
1077                 /* Success */
1078                 ret = 0;
1079         }
1080
1081         DBG("Relayd rotate rename completed successfully");
1082
1083 error:
1084         free(msg);
1085         return ret;
1086 }
1087
1088 int relayd_rotate_pending(struct lttcomm_relayd_sock *rsock, uint64_t chunk_id)
1089 {
1090         int ret;
1091         struct lttcomm_relayd_rotate_pending msg;
1092         struct lttcomm_relayd_rotate_pending_reply reply;
1093
1094         /* Code flow error. Safety net. */
1095         assert(rsock);
1096
1097         DBG("Querying relayd for rotate pending with chunk_id %" PRIu64,
1098                         chunk_id);
1099
1100         memset(&msg, 0, sizeof(msg));
1101         msg.chunk_id = htobe64(chunk_id);
1102
1103         /* Send command */
1104         ret = send_command(rsock, RELAYD_ROTATE_PENDING, (void *) &msg,
1105                         sizeof(msg), 0);
1106         if (ret < 0) {
1107                 goto error;
1108         }
1109
1110         /* Receive response */
1111         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
1112         if (ret < 0) {
1113                 goto error;
1114         }
1115
1116         reply.generic.ret_code = be32toh(reply.generic.ret_code);
1117
1118         /* Return session id or negative ret code. */
1119         if (reply.generic.ret_code != LTTNG_OK) {
1120                 ret = -reply.generic.ret_code;
1121                 ERR("Relayd rotate pending replied with error %d", ret);
1122                 goto error;
1123         } else {
1124                 /* No error, just rotate pending state */
1125                 if (reply.is_pending == 0 || reply.is_pending == 1) {
1126                         ret = reply.is_pending;
1127                         DBG("Relayd rotate pending command completed successfully with result \"%s\"",
1128                                         ret ? "rotation pending" : "rotation NOT pending");
1129                 } else {
1130                         ret = -LTTNG_ERR_UNK;
1131                 }
1132         }
1133
1134 error:
1135         return ret;
1136 }
1137
1138 int relayd_mkdir(struct lttcomm_relayd_sock *rsock, const char *path)
1139 {
1140         int ret;
1141         struct lttcomm_relayd_mkdir *msg;
1142         struct lttcomm_relayd_generic_reply reply;
1143         size_t len;
1144
1145         /* Code flow error. Safety net. */
1146         assert(rsock);
1147
1148         DBG("Relayd mkdir path %s", path);
1149
1150         len = strlen(path) + 1;
1151         msg = zmalloc(sizeof(msg->length) + len);
1152         if (!msg) {
1153                 PERROR("Alloc mkdir msg");
1154                 ret = -1;
1155                 goto error;
1156         }
1157         msg->length = htobe32((uint32_t) len);
1158
1159         if (lttng_strncpy(msg->path, path, len)) {
1160                 ret = -1;
1161                 goto error;
1162         }
1163
1164         /* Send command */
1165         ret = send_command(rsock, RELAYD_MKDIR, (void *) msg,
1166                         sizeof(msg->length) + len, 0);
1167         if (ret < 0) {
1168                 goto error;
1169         }
1170
1171         /* Receive response */
1172         ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
1173         if (ret < 0) {
1174                 goto error;
1175         }
1176
1177         reply.ret_code = be32toh(reply.ret_code);
1178
1179         /* Return session id or negative ret code. */
1180         if (reply.ret_code != LTTNG_OK) {
1181                 ret = -1;
1182                 ERR("Relayd mkdir replied error %d", reply.ret_code);
1183         } else {
1184                 /* Success */
1185                 ret = 0;
1186         }
1187
1188         DBG("Relayd mkdir completed successfully");
1189
1190 error:
1191         free(msg);
1192         return ret;
1193 }