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 _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 <inttypes.h>
  25
  26 #include <common/common.h>
  27 #include <common/defaults.h>
  28 #include <common/sessiond-comm/relayd.h>
  29
  30 #include "relayd.h"
  31
  32 /*
  33  * Send command. Fill up the header and append the data.
  34  */
  35 static int send_command(struct lttcomm_sock *sock,
  36                 enum lttcomm_relayd_command cmd, void *data, size_t size,
  37                 int flags)
  38 {
  39         int ret;
  40         struct lttcomm_relayd_hdr header;
  41         char *buf;
  42         uint64_t buf_size = sizeof(header);
  43
  44         if (data) {
  45                 buf_size += size;
  46         }
  47
  48         buf = zmalloc(buf_size);
  49         if (buf == NULL) {
  50                 PERROR("zmalloc relayd send command buf");
  51                 ret = -1;
  52                 goto alloc_error;
  53         }
  54
  55         header.cmd = htobe32(cmd);
  56         header.data_size = htobe64(size);
  57
  58         /* Zeroed for now since not used. */
  59         header.cmd_version = 0;
  60         header.circuit_id = 0;
  61
  62         /* Prepare buffer to send. */
  63         memcpy(buf, &header, sizeof(header));
  64         if (data) {
  65                 memcpy(buf + sizeof(header), data, size);
  66         }
  67
  68         ret = sock->ops->sendmsg(sock, buf, buf_size, flags);
  69         if (ret < 0) {
  70                 ret = -errno;
  71                 goto error;
  72         }
  73
  74         DBG3("Relayd sending command %d of size %" PRIu64, cmd, buf_size);
  75
  76 error:
  77         free(buf);
  78 alloc_error:
  79         return ret;
  80 }
  81
  82 /*
  83  * Receive reply data on socket. This MUST be call after send_command or else
  84  * could result in unexpected behavior(s).
  85  */
  86 static int recv_reply(struct lttcomm_sock *sock, void *data, size_t size)
  87 {
  88         int ret;
  89
  90         DBG3("Relayd waiting for reply of size %ld", size);
  91
  92         ret = sock->ops->recvmsg(sock, data, size, 0);
  93         if (ret < 0) {
  94                 ret = -errno;
  95                 goto error;
  96         }
  97
  98 error:
  99         return ret;
 100 }
 101
 102 /*
 103  * Send a RELAYD_CREATE_SESSION command to the relayd with the given socket and
 104  * set session_id of the relayd if we have a successful reply from the relayd.
 105  *
 106  * On success, return 0 else a negative value being a lttng_error_code returned
 107  * from the relayd.
 108  */
 109 int relayd_create_session(struct lttcomm_sock *sock, uint64_t *session_id)
 110 {
 111         int ret;
 112         struct lttcomm_relayd_status_session reply;
 113
 114         assert(sock);
 115         assert(session_id);
 116
 117         DBG("Relayd create session");
 118
 119         /* Send command */
 120         ret = send_command(sock, RELAYD_CREATE_SESSION, NULL, 0, 0);
 121         if (ret < 0) {
 122                 goto error;
 123         }
 124
 125         /* Recevie response */
 126         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 127         if (ret < 0) {
 128                 goto error;
 129         }
 130
 131         reply.session_id = be64toh(reply.session_id);
 132         reply.ret_code = be32toh(reply.ret_code);
 133
 134         /* Return session id or negative ret code. */
 135         if (reply.ret_code != LTTNG_OK) {
 136                 ret = -reply.ret_code;
 137                 ERR("Relayd create session replied error %d", ret);
 138                 goto error;
 139         } else {
 140                 ret = 0;
 141                 *session_id = reply.session_id;
 142         }
 143
 144         DBG("Relayd session created with id %" PRIu64, reply.session_id);
 145
 146 error:
 147         return ret;
 148 }
 149
 150 /*
 151  * Add stream on the relayd and assign stream handle to the stream_id argument.
 152  *
 153  * On success return 0 else return ret_code negative value.
 154  */
 155 int relayd_add_stream(struct lttcomm_sock *sock, const char *channel_name,
 156                 const char *pathname, uint64_t *stream_id)
 157 {
 158         int ret;
 159         struct lttcomm_relayd_add_stream msg;
 160         struct lttcomm_relayd_status_stream reply;
 161
 162         /* Code flow error. Safety net. */
 163         assert(sock);
 164         assert(channel_name);
 165         assert(pathname);
 166
 167         DBG("Relayd adding stream for channel name %s", channel_name);
 168
 169         strncpy(msg.channel_name, channel_name, sizeof(msg.channel_name));
 170         strncpy(msg.pathname, pathname, sizeof(msg.pathname));
 171
 172         /* Send command */
 173         ret = send_command(sock, RELAYD_ADD_STREAM, (void *) &msg, sizeof(msg), 0);
 174         if (ret < 0) {
 175                 goto error;
 176         }
 177
 178         /* Waiting for reply */
 179         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 180         if (ret < 0) {
 181                 goto error;
 182         }
 183
 184         /* Back to host bytes order. */
 185         reply.handle = be64toh(reply.handle);
 186         reply.ret_code = be32toh(reply.ret_code);
 187
 188         /* Return session id or negative ret code. */
 189         if (reply.ret_code != LTTNG_OK) {
 190                 ret = -reply.ret_code;
 191                 ERR("Relayd add stream replied error %d", ret);
 192         } else {
 193                 /* Success */
 194                 ret = 0;
 195                 *stream_id = reply.handle;
 196         }
 197
 198         DBG("Relayd stream added successfully with handle %" PRIu64,
 199                 reply.handle);
 200
 201 error:
 202         return ret;
 203 }
 204
 205 /*
 206  * Check version numbers on the relayd.
 207  *
 208  * Return 0 if compatible else negative value.
 209  */
 210 int relayd_version_check(struct lttcomm_sock *sock, uint32_t major,
 211                 uint32_t minor)
 212 {
 213         int ret;
 214         struct lttcomm_relayd_version msg;
 215
 216         /* Code flow error. Safety net. */
 217         assert(sock);
 218
 219         DBG("Relayd version check for major.minor %u.%u", major, minor);
 220
 221         /* Prepare network byte order before transmission. */
 222         msg.major = htobe32(major);
 223         msg.minor = htobe32(minor);
 224
 225         /* Send command */
 226         ret = send_command(sock, RELAYD_VERSION, (void *) &msg, sizeof(msg), 0);
 227         if (ret < 0) {
 228                 goto error;
 229         }
 230
 231         /* Recevie response */
 232         ret = recv_reply(sock, (void *) &msg, sizeof(msg));
 233         if (ret < 0) {
 234                 goto error;
 235         }
 236
 237         /* Set back to host bytes order */
 238         msg.major = be32toh(msg.major);
 239         msg.minor = be32toh(msg.minor);
 240
 241         /*
 242          * Only validate the major version. If the other side is higher,
 243          * communication is not possible. Only major version equal can talk to each
 244          * other. If the minor version differs, the lowest version is used by both
 245          * sides.
 246          *
 247          * For now, before 2.1.0 stable release, we don't have to check the minor
 248          * because this new mechanism with the relayd will only be available with
 249          * 2.1 and NOT 2.0.x.
 250          */
 251         if (msg.major == major) {
 252                 /* Compatible */
 253                 ret = 0;
 254                 DBG2("Relayd version is compatible");
 255                 goto error;
 256         }
 257
 258         /*
 259          * After 2.1.0 release, for the 2.2 release, at this point will have to
 260          * check the minor version in order for the session daemon to know which
 261          * structure to use to communicate with the relayd. If the relayd's minor
 262          * version is higher, it will adapt to our version so we can continue to
 263          * use the latest relayd communication data structure.
 264          */
 265
 266         /* Version number not compatible */
 267         DBG2("Relayd version is NOT compatible. Relayd version %u != %u (us)",
 268                         msg.major, major);
 269         ret = -1;
 270
 271 error:
 272         return ret;
 273 }
 274
 275 /*
 276  * Add stream on the relayd and assign stream handle to the stream_id argument.
 277  *
 278  * On success return 0 else return ret_code negative value.
 279  */
 280 int relayd_send_metadata(struct lttcomm_sock *sock, size_t len)
 281 {
 282         int ret;
 283
 284         /* Code flow error. Safety net. */
 285         assert(sock);
 286
 287         DBG("Relayd sending metadata of size %zu", len);
 288
 289         /* Send command */
 290         ret = send_command(sock, RELAYD_SEND_METADATA, NULL, len, 0);
 291         if (ret < 0) {
 292                 goto error;
 293         }
 294
 295         DBG2("Relayd metadata added successfully");
 296
 297         /*
 298          * After that call, the metadata data MUST be sent to the relayd so the
 299          * receive size on the other end matches the len of the metadata packet
 300          * header. This is why we don't wait for a reply here.
 301          */
 302
 303 error:
 304         return ret;
 305 }
 306
 307 /*
 308  * Connect to relay daemon with an allocated lttcomm_sock.
 309  */
 310 int relayd_connect(struct lttcomm_sock *sock)
 311 {
 312         /* Code flow error. Safety net. */
 313         assert(sock);
 314
 315         DBG3("Relayd connect ...");
 316
 317         return sock->ops->connect(sock);
 318 }
 319
 320 /*
 321  * Close relayd socket with an allocated lttcomm_sock.
 322  */
 323 int relayd_close(struct lttcomm_sock *sock)
 324 {
 325         /* Code flow error. Safety net. */
 326         assert(sock);
 327
 328         DBG3("Relayd closing socket %d", sock->fd);
 329
 330         return sock->ops->close(sock);
 331 }
 332
 333 /*
 334  * Send data header structure to the relayd.
 335  */
 336 int relayd_send_data_hdr(struct lttcomm_sock *sock,
 337                 struct lttcomm_relayd_data_hdr *hdr, size_t size)
 338 {
 339         int ret;
 340
 341         /* Code flow error. Safety net. */
 342         assert(sock);
 343         assert(hdr);
 344
 345         DBG3("Relayd sending data header of size %ld", size);
 346
 347         /* Again, safety net */
 348         if (size == 0) {
 349                 size = sizeof(struct lttcomm_relayd_data_hdr);
 350         }
 351
 352         /* Only send data header. */
 353         ret = sock->ops->sendmsg(sock, hdr, size, 0);
 354         if (ret < 0) {
 355                 ret = -errno;
 356                 goto error;
 357         }
 358
 359         /*
 360          * The data MUST be sent right after that command for the receive on the
 361          * other end to match the size in the header.
 362          */
 363
 364 error:
 365         return ret;
 366 }
 367
 368 /*
 369  * Send close stream command to the relayd.
 370  */
 371 int relayd_send_close_stream(struct lttcomm_sock *sock, uint64_t stream_id,
 372                 uint64_t last_net_seq_num)
 373 {
 374         int ret;
 375         struct lttcomm_relayd_close_stream msg;
 376         struct lttcomm_relayd_generic_reply reply;
 377
 378         /* Code flow error. Safety net. */
 379         assert(sock);
 380
 381         DBG("Relayd closing stream id %" PRIu64, stream_id);
 382
 383         msg.stream_id = htobe64(stream_id);
 384         msg.last_net_seq_num = htobe64(last_net_seq_num);
 385
 386         /* Send command */
 387         ret = send_command(sock, RELAYD_CLOSE_STREAM, (void *) &msg, sizeof(msg), 0);
 388         if (ret < 0) {
 389                 goto error;
 390         }
 391
 392         /* Recevie response */
 393         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 394         if (ret < 0) {
 395                 goto error;
 396         }
 397
 398         reply.ret_code = be32toh(reply.ret_code);
 399
 400         /* Return session id or negative ret code. */
 401         if (reply.ret_code != LTTNG_OK) {
 402                 ret = -reply.ret_code;
 403                 ERR("Relayd close stream replied error %d", ret);
 404         } else {
 405                 /* Success */
 406                 ret = 0;
 407         }
 408
 409         DBG("Relayd close stream id %" PRIu64 " successfully", stream_id);
 410
 411 error:
 412         return ret;
 413 }
 414
 415 /*
 416  * Check for data availability for a given stream id.
 417  *
 418  * Return 0 if NOT pending, 1 if so and a negative value on error.
 419  */
 420 int relayd_data_pending(struct lttcomm_sock *sock, uint64_t stream_id,
 421                 uint64_t last_net_seq_num)
 422 {
 423         int ret;
 424         struct lttcomm_relayd_data_pending msg;
 425         struct lttcomm_relayd_generic_reply reply;
 426
 427         /* Code flow error. Safety net. */
 428         assert(sock);
 429
 430         DBG("Relayd data pending for stream id %" PRIu64, stream_id);
 431
 432         msg.stream_id = htobe64(stream_id);
 433         msg.last_net_seq_num = htobe64(last_net_seq_num);
 434
 435         /* Send command */
 436         ret = send_command(sock, RELAYD_DATA_PENDING, (void *) &msg,
 437                         sizeof(msg), 0);
 438         if (ret < 0) {
 439                 goto error;
 440         }
 441
 442         /* Recevie response */
 443         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 444         if (ret < 0) {
 445                 goto error;
 446         }
 447
 448         reply.ret_code = be32toh(reply.ret_code);
 449
 450         /* Return session id or negative ret code. */
 451         if (reply.ret_code >= LTTNG_OK) {
 452                 ret = -reply.ret_code;
 453                 ERR("Relayd data pending replied error %d", ret);
 454         }
 455
 456         /* At this point, the ret code is either 1 or 0 */
 457         ret = reply.ret_code;
 458
 459         DBG("Relayd data is %s pending for stream id %" PRIu64,
 460                         ret == 1 ? "NOT" : "", stream_id);
 461
 462 error:
 463         return ret;
 464 }
 465
 466 /*
 467  * Check on the relayd side for a quiescent state on the control socket.
 468  */
 469 int relayd_quiescent_control(struct lttcomm_sock *sock,
 470                 uint64_t metadata_stream_id)
 471 {
 472         int ret;
 473         struct lttcomm_relayd_quiescent_control msg;
 474         struct lttcomm_relayd_generic_reply reply;
 475
 476         /* Code flow error. Safety net. */
 477         assert(sock);
 478
 479         DBG("Relayd checking quiescent control state");
 480
 481         msg.stream_id = htobe64(metadata_stream_id);
 482
 483         /* Send command */
 484         ret = send_command(sock, RELAYD_QUIESCENT_CONTROL, &msg, sizeof(msg), 0);
 485         if (ret < 0) {
 486                 goto error;
 487         }
 488
 489         /* Recevie response */
 490         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 491         if (ret < 0) {
 492                 goto error;
 493         }
 494
 495         reply.ret_code = be32toh(reply.ret_code);
 496
 497         /* Return session id or negative ret code. */
 498         if (reply.ret_code != LTTNG_OK) {
 499                 ret = -reply.ret_code;
 500                 ERR("Relayd quiescent control replied error %d", ret);
 501                 goto error;
 502         }
 503
 504         /* Control socket is quiescent */
 505         return 0;
 506
 507 error:
 508         return ret;
 509 }
 510
 511 /*
 512  * Begin a data pending command for a specific session id.
 513  */
 514 int relayd_begin_data_pending(struct lttcomm_sock *sock, uint64_t id)
 515 {
 516         int ret;
 517         struct lttcomm_relayd_begin_data_pending msg;
 518         struct lttcomm_relayd_generic_reply reply;
 519
 520         /* Code flow error. Safety net. */
 521         assert(sock);
 522
 523         DBG("Relayd begin data pending");
 524
 525         msg.session_id = htobe64(id);
 526
 527         /* Send command */
 528         ret = send_command(sock, RELAYD_BEGIN_DATA_PENDING, &msg, sizeof(msg), 0);
 529         if (ret < 0) {
 530                 goto error;
 531         }
 532
 533         /* Recevie response */
 534         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 535         if (ret < 0) {
 536                 goto error;
 537         }
 538
 539         reply.ret_code = be32toh(reply.ret_code);
 540
 541         /* Return session id or negative ret code. */
 542         if (reply.ret_code != LTTNG_OK) {
 543                 ret = -reply.ret_code;
 544                 ERR("Relayd begin data pending replied error %d", ret);
 545                 goto error;
 546         }
 547
 548         return 0;
 549
 550 error:
 551         return ret;
 552 }
 553
 554 /*
 555  * End a data pending command for a specific session id.
 556  *
 557  * Return 0 on success and set is_data_inflight to 0 if no data is being
 558  * streamed or 1 if it is the case.
 559  */
 560 int relayd_end_data_pending(struct lttcomm_sock *sock, uint64_t id,
 561                 unsigned int *is_data_inflight)
 562 {
 563         int ret;
 564         struct lttcomm_relayd_end_data_pending msg;
 565         struct lttcomm_relayd_generic_reply reply;
 566
 567         /* Code flow error. Safety net. */
 568         assert(sock);
 569
 570         DBG("Relayd end data pending");
 571
 572         msg.session_id = htobe64(id);
 573
 574         /* Send command */
 575         ret = send_command(sock, RELAYD_END_DATA_PENDING, &msg, sizeof(msg), 0);
 576         if (ret < 0) {
 577                 goto error;
 578         }
 579
 580         /* Recevie response */
 581         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 582         if (ret < 0) {
 583                 goto error;
 584         }
 585
 586         reply.ret_code = be32toh(reply.ret_code);
 587         if (reply.ret_code < 0) {
 588                 ret = reply.ret_code;
 589                 goto error;
 590         }
 591
 592         *is_data_inflight = reply.ret_code;
 593
 594         DBG("Relayd end data pending is data inflight: %d", reply.ret_code);
 595
 596         return 0;
 597
 598 error:
 599         return ret;
 600 }