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 || ret != size) {
  94                 if (ret == 0) {
  95                         /* Orderly shutdown. */
  96                         DBG("Socket %d has performed an orderly shutdown", sock->fd);
  97                 } else {
  98                         DBG("Receiving reply failed on sock %d for size %lu with ret %d",
  99                                         sock->fd, size, ret);
 100                 }
 101                 /* Always return -1 here and the caller can use errno. */
 102                 ret = -1;
 103                 goto error;
 104         }
 105
 106 error:
 107         return ret;
 108 }
 109
 110 /*
 111  * Send a RELAYD_CREATE_SESSION command to the relayd with the given socket and
 112  * set session_id of the relayd if we have a successful reply from the relayd.
 113  *
 114  * On success, return 0 else a negative value which is either an errno error or
 115  * a lttng error code from the relayd.
 116  */
 117 int relayd_create_session(struct lttcomm_sock *sock, uint64_t *session_id)
 118 {
 119         int ret;
 120         struct lttcomm_relayd_status_session reply;
 121
 122         assert(sock);
 123         assert(session_id);
 124
 125         DBG("Relayd create session");
 126
 127         /* Send command */
 128         ret = send_command(sock, RELAYD_CREATE_SESSION, NULL, 0, 0);
 129         if (ret < 0) {
 130                 goto error;
 131         }
 132
 133         /* Receive response */
 134         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 135         if (ret < 0) {
 136                 goto error;
 137         }
 138
 139         reply.session_id = be64toh(reply.session_id);
 140         reply.ret_code = be32toh(reply.ret_code);
 141
 142         /* Return session id or negative ret code. */
 143         if (reply.ret_code != LTTNG_OK) {
 144                 ret = -1;
 145                 ERR("Relayd create session replied error %d", reply.ret_code);
 146                 goto error;
 147         } else {
 148                 ret = 0;
 149                 *session_id = reply.session_id;
 150         }
 151
 152         DBG("Relayd session created with id %" PRIu64, reply.session_id);
 153
 154 error:
 155         return ret;
 156 }
 157
 158 /*
 159  * Add stream on the relayd and assign stream handle to the stream_id argument.
 160  *
 161  * On success return 0 else return ret_code negative value.
 162  */
 163 int relayd_add_stream(struct lttcomm_sock *sock, const char *channel_name,
 164                 const char *pathname, uint64_t *stream_id)
 165 {
 166         int ret;
 167         struct lttcomm_relayd_add_stream msg;
 168         struct lttcomm_relayd_status_stream reply;
 169
 170         /* Code flow error. Safety net. */
 171         assert(sock);
 172         assert(channel_name);
 173         assert(pathname);
 174
 175         DBG("Relayd adding stream for channel name %s", channel_name);
 176
 177         strncpy(msg.channel_name, channel_name, sizeof(msg.channel_name));
 178         strncpy(msg.pathname, pathname, sizeof(msg.pathname));
 179
 180         /* Send command */
 181         ret = send_command(sock, RELAYD_ADD_STREAM, (void *) &msg, sizeof(msg), 0);
 182         if (ret < 0) {
 183                 goto error;
 184         }
 185
 186         /* Waiting for reply */
 187         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 188         if (ret < 0) {
 189                 goto error;
 190         }
 191
 192         /* Back to host bytes order. */
 193         reply.handle = be64toh(reply.handle);
 194         reply.ret_code = be32toh(reply.ret_code);
 195
 196         /* Return session id or negative ret code. */
 197         if (reply.ret_code != LTTNG_OK) {
 198                 ret = -1;
 199                 ERR("Relayd add stream replied error %d", reply.ret_code);
 200         } else {
 201                 /* Success */
 202                 ret = 0;
 203                 *stream_id = reply.handle;
 204         }
 205
 206         DBG("Relayd stream added successfully with handle %" PRIu64,
 207                 reply.handle);
 208
 209 error:
 210         return ret;
 211 }
 212
 213 /*
 214  * Check version numbers on the relayd.
 215  *
 216  * Return 0 if compatible else negative value.
 217  */
 218 int relayd_version_check(struct lttcomm_sock *sock, uint32_t major,
 219                 uint32_t minor)
 220 {
 221         int ret;
 222         struct lttcomm_relayd_version msg;
 223
 224         /* Code flow error. Safety net. */
 225         assert(sock);
 226
 227         DBG("Relayd version check for major.minor %u.%u", major, minor);
 228
 229         /* Prepare network byte order before transmission. */
 230         msg.major = htobe32(major);
 231         msg.minor = htobe32(minor);
 232
 233         /* Send command */
 234         ret = send_command(sock, RELAYD_VERSION, (void *) &msg, sizeof(msg), 0);
 235         if (ret < 0) {
 236                 goto error;
 237         }
 238
 239         /* Receive response */
 240         ret = recv_reply(sock, (void *) &msg, sizeof(msg));
 241         if (ret < 0) {
 242                 goto error;
 243         }
 244
 245         /* Set back to host bytes order */
 246         msg.major = be32toh(msg.major);
 247         msg.minor = be32toh(msg.minor);
 248
 249         /*
 250          * Only validate the major version. If the other side is higher,
 251          * communication is not possible. Only major version equal can talk to each
 252          * other. If the minor version differs, the lowest version is used by both
 253          * sides.
 254          *
 255          * For now, before 2.1.0 stable release, we don't have to check the minor
 256          * because this new mechanism with the relayd will only be available with
 257          * 2.1 and NOT 2.0.x.
 258          */
 259         if (msg.major == major) {
 260                 /* Compatible */
 261                 ret = 0;
 262                 DBG2("Relayd version is compatible");
 263                 goto error;
 264         }
 265
 266         /*
 267          * After 2.1.0 release, for the 2.2 release, at this point will have to
 268          * check the minor version in order for the session daemon to know which
 269          * structure to use to communicate with the relayd. If the relayd's minor
 270          * version is higher, it will adapt to our version so we can continue to
 271          * use the latest relayd communication data structure.
 272          */
 273
 274         /* Version number not compatible */
 275         DBG2("Relayd version is NOT compatible. Relayd version %u != %u (us)",
 276                         msg.major, major);
 277         ret = -1;
 278
 279 error:
 280         return ret;
 281 }
 282
 283 /*
 284  * Add stream on the relayd and assign stream handle to the stream_id argument.
 285  *
 286  * On success return 0 else return ret_code negative value.
 287  */
 288 int relayd_send_metadata(struct lttcomm_sock *sock, size_t len)
 289 {
 290         int ret;
 291
 292         /* Code flow error. Safety net. */
 293         assert(sock);
 294
 295         DBG("Relayd sending metadata of size %zu", len);
 296
 297         /* Send command */
 298         ret = send_command(sock, RELAYD_SEND_METADATA, NULL, len, 0);
 299         if (ret < 0) {
 300                 goto error;
 301         }
 302
 303         DBG2("Relayd metadata added successfully");
 304
 305         /*
 306          * After that call, the metadata data MUST be sent to the relayd so the
 307          * receive size on the other end matches the len of the metadata packet
 308          * header. This is why we don't wait for a reply here.
 309          */
 310
 311 error:
 312         return ret;
 313 }
 314
 315 /*
 316  * Connect to relay daemon with an allocated lttcomm_sock.
 317  */
 318 int relayd_connect(struct lttcomm_sock *sock)
 319 {
 320         /* Code flow error. Safety net. */
 321         assert(sock);
 322
 323         DBG3("Relayd connect ...");
 324
 325         return sock->ops->connect(sock);
 326 }
 327
 328 /*
 329  * Close relayd socket with an allocated lttcomm_sock.
 330  */
 331 int relayd_close(struct lttcomm_sock *sock)
 332 {
 333         /* Code flow error. Safety net. */
 334         assert(sock);
 335
 336         DBG3("Relayd closing socket %d", sock->fd);
 337
 338         return sock->ops->close(sock);
 339 }
 340
 341 /*
 342  * Send data header structure to the relayd.
 343  */
 344 int relayd_send_data_hdr(struct lttcomm_sock *sock,
 345                 struct lttcomm_relayd_data_hdr *hdr, size_t size)
 346 {
 347         int ret;
 348
 349         /* Code flow error. Safety net. */
 350         assert(sock);
 351         assert(hdr);
 352
 353         DBG3("Relayd sending data header of size %ld", size);
 354
 355         /* Again, safety net */
 356         if (size == 0) {
 357                 size = sizeof(struct lttcomm_relayd_data_hdr);
 358         }
 359
 360         /* Only send data header. */
 361         ret = sock->ops->sendmsg(sock, hdr, size, 0);
 362         if (ret < 0) {
 363                 ret = -errno;
 364                 goto error;
 365         }
 366
 367         /*
 368          * The data MUST be sent right after that command for the receive on the
 369          * other end to match the size in the header.
 370          */
 371
 372 error:
 373         return ret;
 374 }
 375
 376 /*
 377  * Send close stream command to the relayd.
 378  */
 379 int relayd_send_close_stream(struct lttcomm_sock *sock, uint64_t stream_id,
 380                 uint64_t last_net_seq_num)
 381 {
 382         int ret;
 383         struct lttcomm_relayd_close_stream msg;
 384         struct lttcomm_relayd_generic_reply reply;
 385
 386         /* Code flow error. Safety net. */
 387         assert(sock);
 388
 389         DBG("Relayd closing stream id %" PRIu64, stream_id);
 390
 391         msg.stream_id = htobe64(stream_id);
 392         msg.last_net_seq_num = htobe64(last_net_seq_num);
 393
 394         /* Send command */
 395         ret = send_command(sock, RELAYD_CLOSE_STREAM, (void *) &msg, sizeof(msg), 0);
 396         if (ret < 0) {
 397                 goto error;
 398         }
 399
 400         /* Receive response */
 401         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 402         if (ret < 0) {
 403                 goto error;
 404         }
 405
 406         reply.ret_code = be32toh(reply.ret_code);
 407
 408         /* Return session id or negative ret code. */
 409         if (reply.ret_code != LTTNG_OK) {
 410                 ret = -1;
 411                 ERR("Relayd close stream replied error %d", reply.ret_code);
 412         } else {
 413                 /* Success */
 414                 ret = 0;
 415         }
 416
 417         DBG("Relayd close stream id %" PRIu64 " successfully", stream_id);
 418
 419 error:
 420         return ret;
 421 }
 422
 423 /*
 424  * Check for data availability for a given stream id.
 425  *
 426  * Return 0 if NOT pending, 1 if so and a negative value on error.
 427  */
 428 int relayd_data_pending(struct lttcomm_sock *sock, uint64_t stream_id,
 429                 uint64_t last_net_seq_num)
 430 {
 431         int ret;
 432         struct lttcomm_relayd_data_pending msg;
 433         struct lttcomm_relayd_generic_reply reply;
 434
 435         /* Code flow error. Safety net. */
 436         assert(sock);
 437
 438         DBG("Relayd data pending for stream id %" PRIu64, stream_id);
 439
 440         msg.stream_id = htobe64(stream_id);
 441         msg.last_net_seq_num = htobe64(last_net_seq_num);
 442
 443         /* Send command */
 444         ret = send_command(sock, RELAYD_DATA_PENDING, (void *) &msg,
 445                         sizeof(msg), 0);
 446         if (ret < 0) {
 447                 goto error;
 448         }
 449
 450         /* Receive response */
 451         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 452         if (ret < 0) {
 453                 goto error;
 454         }
 455
 456         reply.ret_code = be32toh(reply.ret_code);
 457
 458         /* Return session id or negative ret code. */
 459         if (reply.ret_code >= LTTNG_OK) {
 460                 ERR("Relayd data pending replied error %d", reply.ret_code);
 461         }
 462
 463         /* At this point, the ret code is either 1 or 0 */
 464         ret = reply.ret_code;
 465
 466         DBG("Relayd data is %s pending for stream id %" PRIu64,
 467                         ret == 1 ? "" : "NOT", stream_id);
 468
 469 error:
 470         return ret;
 471 }
 472
 473 /*
 474  * Check on the relayd side for a quiescent state on the control socket.
 475  */
 476 int relayd_quiescent_control(struct lttcomm_sock *sock,
 477                 uint64_t metadata_stream_id)
 478 {
 479         int ret;
 480         struct lttcomm_relayd_quiescent_control msg;
 481         struct lttcomm_relayd_generic_reply reply;
 482
 483         /* Code flow error. Safety net. */
 484         assert(sock);
 485
 486         DBG("Relayd checking quiescent control state");
 487
 488         msg.stream_id = htobe64(metadata_stream_id);
 489
 490         /* Send command */
 491         ret = send_command(sock, RELAYD_QUIESCENT_CONTROL, &msg, sizeof(msg), 0);
 492         if (ret < 0) {
 493                 goto error;
 494         }
 495
 496         /* Receive response */
 497         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 498         if (ret < 0) {
 499                 goto error;
 500         }
 501
 502         reply.ret_code = be32toh(reply.ret_code);
 503
 504         /* Return session id or negative ret code. */
 505         if (reply.ret_code != LTTNG_OK) {
 506                 ret = -1;
 507                 ERR("Relayd quiescent control replied error %d", reply.ret_code);
 508                 goto error;
 509         }
 510
 511         /* Control socket is quiescent */
 512         return 0;
 513
 514 error:
 515         return ret;
 516 }
 517
 518 /*
 519  * Begin a data pending command for a specific session id.
 520  */
 521 int relayd_begin_data_pending(struct lttcomm_sock *sock, uint64_t id)
 522 {
 523         int ret;
 524         struct lttcomm_relayd_begin_data_pending msg;
 525         struct lttcomm_relayd_generic_reply reply;
 526
 527         /* Code flow error. Safety net. */
 528         assert(sock);
 529
 530         DBG("Relayd begin data pending");
 531
 532         msg.session_id = htobe64(id);
 533
 534         /* Send command */
 535         ret = send_command(sock, RELAYD_BEGIN_DATA_PENDING, &msg, sizeof(msg), 0);
 536         if (ret < 0) {
 537                 goto error;
 538         }
 539
 540         /* Receive response */
 541         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 542         if (ret < 0) {
 543                 goto error;
 544         }
 545
 546         reply.ret_code = be32toh(reply.ret_code);
 547
 548         /* Return session id or negative ret code. */
 549         if (reply.ret_code != LTTNG_OK) {
 550                 ret = -1;
 551                 ERR("Relayd begin data pending replied error %d", reply.ret_code);
 552                 goto error;
 553         }
 554
 555         return 0;
 556
 557 error:
 558         return ret;
 559 }
 560
 561 /*
 562  * End a data pending command for a specific session id.
 563  *
 564  * Return 0 on success and set is_data_inflight to 0 if no data is being
 565  * streamed or 1 if it is the case.
 566  */
 567 int relayd_end_data_pending(struct lttcomm_sock *sock, uint64_t id,
 568                 unsigned int *is_data_inflight)
 569 {
 570         int ret;
 571         struct lttcomm_relayd_end_data_pending msg;
 572         struct lttcomm_relayd_generic_reply reply;
 573
 574         /* Code flow error. Safety net. */
 575         assert(sock);
 576
 577         DBG("Relayd end data pending");
 578
 579         msg.session_id = htobe64(id);
 580
 581         /* Send command */
 582         ret = send_command(sock, RELAYD_END_DATA_PENDING, &msg, sizeof(msg), 0);
 583         if (ret < 0) {
 584                 goto error;
 585         }
 586
 587         /* Receive response */
 588         ret = recv_reply(sock, (void *) &reply, sizeof(reply));
 589         if (ret < 0) {
 590                 goto error;
 591         }
 592
 593         reply.ret_code = be32toh(reply.ret_code);
 594         if (reply.ret_code < 0) {
 595                 ret = reply.ret_code;
 596                 goto error;
 597         }
 598
 599         *is_data_inflight = reply.ret_code;
 600
 601         DBG("Relayd end data pending is data inflight: %d", reply.ret_code);
 602
 603         return 0;
 604
 605 error:
 606         return ret;
 607 }