liblttng-ust-ctl/ustctl.c

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  * Copyright (C) 2011-2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; version 2 of the License only.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <string.h>
  21 #include <lttng/ust-ctl.h>
  22 #include <lttng/ust-abi.h>
  23 #include <lttng/ust-events.h>
  24 #include <sys/mman.h>
  25 #include <byteswap.h>
  26
  27 #include <usterr-signal-safe.h>
  28 #include <ust-comm.h>
  29 #include <helper.h>
  30
  31 #include "../libringbuffer/backend.h"
  32 #include "../libringbuffer/frontend.h"
  33 #include "../liblttng-ust/wait.h"
  34
  35 /*
  36  * Number of milliseconds to retry before failing metadata writes on
  37  * buffer full condition. (10 seconds)
  38  */
  39 #define LTTNG_METADATA_TIMEOUT_MSEC     10000
  40
  41 /*
  42  * Channel representation within consumer.
  43  */
  44 struct ustctl_consumer_channel {
  45         struct lttng_channel *chan;             /* lttng channel buffers */
  46
  47         /* initial attributes */
  48         struct ustctl_consumer_channel_attr attr;
  49         int wait_fd;                            /* monitor close() */
  50         int wakeup_fd;                          /* monitor close() */
  51 };
  52
  53 /*
  54  * Stream representation within consumer.
  55  */
  56 struct ustctl_consumer_stream {
  57         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
  58         struct lttng_ust_lib_ring_buffer *buf;
  59         struct ustctl_consumer_channel *chan;
  60         int shm_fd, wait_fd, wakeup_fd;
  61         int cpu;
  62         uint64_t memory_map_size;
  63 };
  64
  65 extern void lttng_ring_buffer_client_overwrite_init(void);
  66 extern void lttng_ring_buffer_client_overwrite_rt_init(void);
  67 extern void lttng_ring_buffer_client_discard_init(void);
  68 extern void lttng_ring_buffer_client_discard_rt_init(void);
  69 extern void lttng_ring_buffer_metadata_client_init(void);
  70 extern void lttng_ring_buffer_client_overwrite_exit(void);
  71 extern void lttng_ring_buffer_client_overwrite_rt_exit(void);
  72 extern void lttng_ring_buffer_client_discard_exit(void);
  73 extern void lttng_ring_buffer_client_discard_rt_exit(void);
  74 extern void lttng_ring_buffer_metadata_client_exit(void);
  75
  76 volatile enum ust_loglevel ust_loglevel;
  77
  78 int ustctl_release_handle(int sock, int handle)
  79 {
  80         struct ustcomm_ust_msg lum;
  81         struct ustcomm_ust_reply lur;
  82
  83         if (sock < 0 || handle < 0)
  84                 return 0;
  85         memset(&lum, 0, sizeof(lum));
  86         lum.handle = handle;
  87         lum.cmd = LTTNG_UST_RELEASE;
  88         return ustcomm_send_app_cmd(sock, &lum, &lur);
  89 }
  90
  91 /*
  92  * If sock is negative, it means we don't have to notify the other side
  93  * (e.g. application has already vanished).
  94  */
  95 int ustctl_release_object(int sock, struct lttng_ust_object_data *data)
  96 {
  97         int ret;
  98
  99         if (!data)
 100                 return -EINVAL;
 101
 102         switch (data->type) {
 103         case LTTNG_UST_OBJECT_TYPE_CHANNEL:
 104                 if (data->u.channel.wakeup_fd >= 0) {
 105                         ret = close(data->u.channel.wakeup_fd);
 106                         if (ret < 0) {
 107                                 ret = -errno;
 108                                 return ret;
 109                         }
 110                 }
 111                 free(data->u.channel.data);
 112                 break;
 113         case LTTNG_UST_OBJECT_TYPE_STREAM:
 114                 if (data->u.stream.shm_fd >= 0) {
 115                         ret = close(data->u.stream.shm_fd);
 116                         if (ret < 0) {
 117                                 ret = -errno;
 118                                 return ret;
 119                         }
 120                 }
 121                 if (data->u.stream.wakeup_fd >= 0) {
 122                         ret = close(data->u.stream.wakeup_fd);
 123                         if (ret < 0) {
 124                                 ret = -errno;
 125                                 return ret;
 126                         }
 127                 }
 128                 break;
 129         case LTTNG_UST_OBJECT_TYPE_EVENT:
 130         case LTTNG_UST_OBJECT_TYPE_CONTEXT:
 131                 break;
 132         default:
 133                 assert(0);
 134         }
 135         return ustctl_release_handle(sock, data->handle);
 136 }
 137
 138 /*
 139  * Send registration done packet to the application.
 140  */
 141 int ustctl_register_done(int sock)
 142 {
 143         struct ustcomm_ust_msg lum;
 144         struct ustcomm_ust_reply lur;
 145         int ret;
 146
 147         DBG("Sending register done command to %d", sock);
 148         memset(&lum, 0, sizeof(lum));
 149         lum.handle = LTTNG_UST_ROOT_HANDLE;
 150         lum.cmd = LTTNG_UST_REGISTER_DONE;
 151         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 152         if (ret)
 153                 return ret;
 154         return 0;
 155 }
 156
 157 /*
 158  * returns session handle.
 159  */
 160 int ustctl_create_session(int sock)
 161 {
 162         struct ustcomm_ust_msg lum;
 163         struct ustcomm_ust_reply lur;
 164         int ret, session_handle;
 165
 166         /* Create session */
 167         memset(&lum, 0, sizeof(lum));
 168         lum.handle = LTTNG_UST_ROOT_HANDLE;
 169         lum.cmd = LTTNG_UST_SESSION;
 170         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 171         if (ret)
 172                 return ret;
 173         session_handle = lur.ret_val;
 174         DBG("received session handle %u", session_handle);
 175         return session_handle;
 176 }
 177
 178 int ustctl_create_event(int sock, struct lttng_ust_event *ev,
 179                 struct lttng_ust_object_data *channel_data,
 180                 struct lttng_ust_object_data **_event_data)
 181 {
 182         struct ustcomm_ust_msg lum;
 183         struct ustcomm_ust_reply lur;
 184         struct lttng_ust_object_data *event_data;
 185         int ret;
 186
 187         if (!channel_data || !_event_data)
 188                 return -EINVAL;
 189
 190         event_data = zmalloc(sizeof(*event_data));
 191         if (!event_data)
 192                 return -ENOMEM;
 193         event_data->type = LTTNG_UST_OBJECT_TYPE_EVENT;
 194         memset(&lum, 0, sizeof(lum));
 195         lum.handle = channel_data->handle;
 196         lum.cmd = LTTNG_UST_EVENT;
 197         strncpy(lum.u.event.name, ev->name,
 198                 LTTNG_UST_SYM_NAME_LEN);
 199         lum.u.event.instrumentation = ev->instrumentation;
 200         lum.u.event.loglevel_type = ev->loglevel_type;
 201         lum.u.event.loglevel = ev->loglevel;
 202         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 203         if (ret) {
 204                 free(event_data);
 205                 return ret;
 206         }
 207         event_data->handle = lur.ret_val;
 208         DBG("received event handle %u", event_data->handle);
 209         *_event_data = event_data;
 210         return 0;
 211 }
 212
 213 int ustctl_add_context(int sock, struct lttng_ust_context *ctx,
 214                 struct lttng_ust_object_data *obj_data,
 215                 struct lttng_ust_object_data **_context_data)
 216 {
 217         struct ustcomm_ust_msg lum;
 218         struct ustcomm_ust_reply lur;
 219         struct lttng_ust_object_data *context_data;
 220         int ret;
 221
 222         if (!obj_data || !_context_data)
 223                 return -EINVAL;
 224
 225         context_data = zmalloc(sizeof(*context_data));
 226         if (!context_data)
 227                 return -ENOMEM;
 228         context_data->type = LTTNG_UST_OBJECT_TYPE_CONTEXT;
 229         memset(&lum, 0, sizeof(lum));
 230         lum.handle = obj_data->handle;
 231         lum.cmd = LTTNG_UST_CONTEXT;
 232         lum.u.context.ctx = ctx->ctx;
 233         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 234         if (ret) {
 235                 free(context_data);
 236                 return ret;
 237         }
 238         context_data->handle = -1;
 239         DBG("Context created successfully");
 240         *_context_data = context_data;
 241         return ret;
 242 }
 243
 244 int ustctl_set_filter(int sock, struct lttng_ust_filter_bytecode *bytecode,
 245                 struct lttng_ust_object_data *obj_data)
 246 {
 247         struct ustcomm_ust_msg lum;
 248         struct ustcomm_ust_reply lur;
 249         int ret;
 250
 251         if (!obj_data)
 252                 return -EINVAL;
 253
 254         memset(&lum, 0, sizeof(lum));
 255         lum.handle = obj_data->handle;
 256         lum.cmd = LTTNG_UST_FILTER;
 257         lum.u.filter.data_size = bytecode->len;
 258         lum.u.filter.reloc_offset = bytecode->reloc_offset;
 259         lum.u.filter.seqnum = bytecode->seqnum;
 260
 261         ret = ustcomm_send_app_msg(sock, &lum);
 262         if (ret)
 263                 return ret;
 264         /* send var len bytecode */
 265         ret = ustcomm_send_unix_sock(sock, bytecode->data,
 266                                 bytecode->len);
 267         if (ret < 0) {
 268                 return ret;
 269         }
 270         if (ret != bytecode->len)
 271                 return -EINVAL;
 272         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 273 }
 274
 275 /* Enable event, channel and session ioctl */
 276 int ustctl_enable(int sock, struct lttng_ust_object_data *object)
 277 {
 278         struct ustcomm_ust_msg lum;
 279         struct ustcomm_ust_reply lur;
 280         int ret;
 281
 282         if (!object)
 283                 return -EINVAL;
 284
 285         memset(&lum, 0, sizeof(lum));
 286         lum.handle = object->handle;
 287         lum.cmd = LTTNG_UST_ENABLE;
 288         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 289         if (ret)
 290                 return ret;
 291         DBG("enabled handle %u", object->handle);
 292         return 0;
 293 }
 294
 295 /* Disable event, channel and session ioctl */
 296 int ustctl_disable(int sock, struct lttng_ust_object_data *object)
 297 {
 298         struct ustcomm_ust_msg lum;
 299         struct ustcomm_ust_reply lur;
 300         int ret;
 301
 302         if (!object)
 303                 return -EINVAL;
 304
 305         memset(&lum, 0, sizeof(lum));
 306         lum.handle = object->handle;
 307         lum.cmd = LTTNG_UST_DISABLE;
 308         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 309         if (ret)
 310                 return ret;
 311         DBG("disable handle %u", object->handle);
 312         return 0;
 313 }
 314
 315 int ustctl_start_session(int sock, int handle)
 316 {
 317         struct lttng_ust_object_data obj;
 318
 319         obj.handle = handle;
 320         return ustctl_enable(sock, &obj);
 321 }
 322
 323 int ustctl_stop_session(int sock, int handle)
 324 {
 325         struct lttng_ust_object_data obj;
 326
 327         obj.handle = handle;
 328         return ustctl_disable(sock, &obj);
 329 }
 330
 331 int ustctl_tracepoint_list(int sock)
 332 {
 333         struct ustcomm_ust_msg lum;
 334         struct ustcomm_ust_reply lur;
 335         int ret, tp_list_handle;
 336
 337         memset(&lum, 0, sizeof(lum));
 338         lum.handle = LTTNG_UST_ROOT_HANDLE;
 339         lum.cmd = LTTNG_UST_TRACEPOINT_LIST;
 340         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 341         if (ret)
 342                 return ret;
 343         tp_list_handle = lur.ret_val;
 344         DBG("received tracepoint list handle %u", tp_list_handle);
 345         return tp_list_handle;
 346 }
 347
 348 int ustctl_tracepoint_list_get(int sock, int tp_list_handle,
 349                 struct lttng_ust_tracepoint_iter *iter)
 350 {
 351         struct ustcomm_ust_msg lum;
 352         struct ustcomm_ust_reply lur;
 353         int ret;
 354
 355         if (!iter)
 356                 return -EINVAL;
 357
 358         memset(&lum, 0, sizeof(lum));
 359         lum.handle = tp_list_handle;
 360         lum.cmd = LTTNG_UST_TRACEPOINT_LIST_GET;
 361         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 362         if (ret)
 363                 return ret;
 364         DBG("received tracepoint list entry name %s loglevel %d",
 365                 lur.u.tracepoint.name,
 366                 lur.u.tracepoint.loglevel);
 367         memcpy(iter, &lur.u.tracepoint, sizeof(*iter));
 368         return 0;
 369 }
 370
 371 int ustctl_tracepoint_field_list(int sock)
 372 {
 373         struct ustcomm_ust_msg lum;
 374         struct ustcomm_ust_reply lur;
 375         int ret, tp_field_list_handle;
 376
 377         memset(&lum, 0, sizeof(lum));
 378         lum.handle = LTTNG_UST_ROOT_HANDLE;
 379         lum.cmd = LTTNG_UST_TRACEPOINT_FIELD_LIST;
 380         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 381         if (ret)
 382                 return ret;
 383         tp_field_list_handle = lur.ret_val;
 384         DBG("received tracepoint field list handle %u", tp_field_list_handle);
 385         return tp_field_list_handle;
 386 }
 387
 388 int ustctl_tracepoint_field_list_get(int sock, int tp_field_list_handle,
 389                 struct lttng_ust_field_iter *iter)
 390 {
 391         struct ustcomm_ust_msg lum;
 392         struct ustcomm_ust_reply lur;
 393         int ret;
 394         ssize_t len;
 395
 396         if (!iter)
 397                 return -EINVAL;
 398
 399         memset(&lum, 0, sizeof(lum));
 400         lum.handle = tp_field_list_handle;
 401         lum.cmd = LTTNG_UST_TRACEPOINT_FIELD_LIST_GET;
 402         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 403         if (ret)
 404                 return ret;
 405         len = ustcomm_recv_unix_sock(sock, iter, sizeof(*iter));
 406         if (len != sizeof(*iter)) {
 407                 return -EINVAL;
 408         }
 409         DBG("received tracepoint field list entry event_name %s event_loglevel %d field_name %s field_type %d",
 410                 iter->event_name,
 411                 iter->loglevel,
 412                 iter->field_name,
 413                 iter->type);
 414         return 0;
 415 }
 416
 417 int ustctl_tracer_version(int sock, struct lttng_ust_tracer_version *v)
 418 {
 419         struct ustcomm_ust_msg lum;
 420         struct ustcomm_ust_reply lur;
 421         int ret;
 422
 423         if (!v)
 424                 return -EINVAL;
 425
 426         memset(&lum, 0, sizeof(lum));
 427         lum.handle = LTTNG_UST_ROOT_HANDLE;
 428         lum.cmd = LTTNG_UST_TRACER_VERSION;
 429         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 430         if (ret)
 431                 return ret;
 432         memcpy(v, &lur.u.version, sizeof(*v));
 433         DBG("received tracer version");
 434         return 0;
 435 }
 436
 437 int ustctl_wait_quiescent(int sock)
 438 {
 439         struct ustcomm_ust_msg lum;
 440         struct ustcomm_ust_reply lur;
 441         int ret;
 442
 443         memset(&lum, 0, sizeof(lum));
 444         lum.handle = LTTNG_UST_ROOT_HANDLE;
 445         lum.cmd = LTTNG_UST_WAIT_QUIESCENT;
 446         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 447         if (ret)
 448                 return ret;
 449         DBG("waited for quiescent state");
 450         return 0;
 451 }
 452
 453 int ustctl_calibrate(int sock, struct lttng_ust_calibrate *calibrate)
 454 {
 455         if (!calibrate)
 456                 return -EINVAL;
 457
 458         return -ENOSYS;
 459 }
 460
 461 int ustctl_sock_flush_buffer(int sock, struct lttng_ust_object_data *object)
 462 {
 463         struct ustcomm_ust_msg lum;
 464         struct ustcomm_ust_reply lur;
 465         int ret;
 466
 467         if (!object)
 468                 return -EINVAL;
 469
 470         memset(&lum, 0, sizeof(lum));
 471         lum.handle = object->handle;
 472         lum.cmd = LTTNG_UST_FLUSH_BUFFER;
 473         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 474         if (ret)
 475                 return ret;
 476         DBG("flushed buffer handle %u", object->handle);
 477         return 0;
 478 }
 479
 480 static
 481 int ustctl_send_channel(int sock,
 482                 enum lttng_ust_chan_type type,
 483                 void *data,
 484                 uint64_t size,
 485                 int wakeup_fd,
 486                 int send_fd_only)
 487 {
 488         ssize_t len;
 489
 490         if (!send_fd_only) {
 491                 /* Send mmap size */
 492                 len = ustcomm_send_unix_sock(sock, &size, sizeof(size));
 493                 if (len != sizeof(size)) {
 494                         if (len < 0)
 495                                 return len;
 496                         else
 497                                 return -EIO;
 498                 }
 499
 500                 /* Send channel type */
 501                 len = ustcomm_send_unix_sock(sock, &type, sizeof(type));
 502                 if (len != sizeof(type)) {
 503                         if (len < 0)
 504                                 return len;
 505                         else
 506                                 return -EIO;
 507                 }
 508         }
 509
 510         /* Send channel data */
 511         len = ustcomm_send_unix_sock(sock, data, size);
 512         if (len != size) {
 513                 if (len < 0)
 514                         return len;
 515                 else
 516                         return -EIO;
 517         }
 518
 519         /* Send wakeup fd */
 520         len = ustcomm_send_fds_unix_sock(sock, &wakeup_fd, 1);
 521         if (len <= 0) {
 522                 if (len < 0)
 523                         return len;
 524                 else
 525                         return -EIO;
 526         }
 527         return 0;
 528 }
 529
 530 static
 531 int ustctl_send_stream(int sock,
 532                 uint32_t stream_nr,
 533                 uint64_t memory_map_size,
 534                 int shm_fd, int wakeup_fd,
 535                 int send_fd_only)
 536 {
 537         ssize_t len;
 538         int fds[2];
 539
 540         if (!send_fd_only) {
 541                 if (shm_fd < 0) {
 542                         /* finish iteration */
 543                         uint64_t v = -1;
 544
 545                         len = ustcomm_send_unix_sock(sock, &v, sizeof(v));
 546                         if (len != sizeof(v)) {
 547                                 if (len < 0)
 548                                         return len;
 549                                 else
 550                                         return -EIO;
 551                         }
 552                         return 0;
 553                 }
 554
 555                 /* Send mmap size */
 556                 len = ustcomm_send_unix_sock(sock, &memory_map_size,
 557                         sizeof(memory_map_size));
 558                 if (len != sizeof(memory_map_size)) {
 559                         if (len < 0)
 560                                 return len;
 561                         else
 562                                 return -EIO;
 563                 }
 564
 565                 /* Send stream nr */
 566                 len = ustcomm_send_unix_sock(sock, &stream_nr,
 567                         sizeof(stream_nr));
 568                 if (len != sizeof(stream_nr)) {
 569                         if (len < 0)
 570                                 return len;
 571                         else
 572                                 return -EIO;
 573                 }
 574         }
 575
 576         /* Send shm fd and wakeup fd */
 577         fds[0] = shm_fd;
 578         fds[1] = wakeup_fd;
 579         len = ustcomm_send_fds_unix_sock(sock, fds, 2);
 580         if (len <= 0) {
 581                 if (len < 0)
 582                         return len;
 583                 else
 584                         return -EIO;
 585         }
 586         return 0;
 587 }
 588
 589 int ustctl_recv_channel_from_consumer(int sock,
 590                 struct lttng_ust_object_data **_channel_data)
 591 {
 592         struct lttng_ust_object_data *channel_data;
 593         ssize_t len;
 594         int wakeup_fd;
 595         int ret;
 596
 597         channel_data = zmalloc(sizeof(*channel_data));
 598         if (!channel_data) {
 599                 ret = -ENOMEM;
 600                 goto error_alloc;
 601         }
 602         channel_data->type = LTTNG_UST_OBJECT_TYPE_CHANNEL;
 603         channel_data->handle = -1;
 604
 605         /* recv mmap size */
 606         len = ustcomm_recv_unix_sock(sock, &channel_data->size,
 607                         sizeof(channel_data->size));
 608         if (len != sizeof(channel_data->size)) {
 609                 if (len < 0)
 610                         ret = len;
 611                 else
 612                         ret = -EINVAL;
 613                 goto error;
 614         }
 615
 616         /* recv channel type */
 617         len = ustcomm_recv_unix_sock(sock, &channel_data->u.channel.type,
 618                         sizeof(channel_data->u.channel.type));
 619         if (len != sizeof(channel_data->u.channel.type)) {
 620                 if (len < 0)
 621                         ret = len;
 622                 else
 623                         ret = -EINVAL;
 624                 goto error;
 625         }
 626
 627         /* recv channel data */
 628         channel_data->u.channel.data = zmalloc(channel_data->size);
 629         if (!channel_data->u.channel.data) {
 630                 ret = -ENOMEM;
 631                 goto error;
 632         }
 633         len = ustcomm_recv_unix_sock(sock, channel_data->u.channel.data,
 634                         channel_data->size);
 635         if (len != channel_data->size) {
 636                 if (len < 0)
 637                         ret = len;
 638                 else
 639                         ret = -EINVAL;
 640                 goto error_recv_data;
 641         }
 642         /* recv wakeup fd */
 643         len = ustcomm_recv_fds_unix_sock(sock, &wakeup_fd, 1);
 644         if (len <= 0) {
 645                 if (len < 0) {
 646                         ret = len;
 647                         goto error_recv_data;
 648                 } else {
 649                         ret = -EIO;
 650                         goto error_recv_data;
 651                 }
 652         }
 653         channel_data->u.channel.wakeup_fd = wakeup_fd;
 654         *_channel_data = channel_data;
 655         return 0;
 656
 657 error_recv_data:
 658         free(channel_data->u.channel.data);
 659 error:
 660         free(channel_data);
 661 error_alloc:
 662         return ret;
 663 }
 664
 665 int ustctl_recv_stream_from_consumer(int sock,
 666                 struct lttng_ust_object_data **_stream_data)
 667 {
 668         struct lttng_ust_object_data *stream_data;
 669         ssize_t len;
 670         int ret;
 671         int fds[2];
 672
 673         stream_data = zmalloc(sizeof(*stream_data));
 674         if (!stream_data) {
 675                 ret = -ENOMEM;
 676                 goto error_alloc;
 677         }
 678
 679         stream_data->type = LTTNG_UST_OBJECT_TYPE_STREAM;
 680         stream_data->handle = -1;
 681
 682         /* recv mmap size */
 683         len = ustcomm_recv_unix_sock(sock, &stream_data->size,
 684                         sizeof(stream_data->size));
 685         if (len != sizeof(stream_data->size)) {
 686                 if (len < 0)
 687                         ret = len;
 688                 else
 689                         ret = -EINVAL;
 690                 goto error;
 691         }
 692         if (stream_data->size == -1) {
 693                 ret = -LTTNG_UST_ERR_NOENT;
 694                 goto error;
 695         }
 696
 697         /* recv stream nr */
 698         len = ustcomm_recv_unix_sock(sock, &stream_data->u.stream.stream_nr,
 699                         sizeof(stream_data->u.stream.stream_nr));
 700         if (len != sizeof(stream_data->u.stream.stream_nr)) {
 701                 if (len < 0)
 702                         ret = len;
 703                 else
 704                         ret = -EINVAL;
 705                 goto error;
 706         }
 707
 708         /* recv shm fd and wakeup fd */
 709         len = ustcomm_recv_fds_unix_sock(sock, fds, 2);
 710         if (len <= 0) {
 711                 if (len < 0) {
 712                         ret = len;
 713                         goto error;
 714                 } else {
 715                         ret = -EIO;
 716                         goto error;
 717                 }
 718         }
 719         stream_data->u.stream.shm_fd = fds[0];
 720         stream_data->u.stream.wakeup_fd = fds[1];
 721         *_stream_data = stream_data;
 722         return 0;
 723
 724 error:
 725         free(stream_data);
 726 error_alloc:
 727         return ret;
 728 }
 729
 730 int ustctl_send_channel_to_ust(int sock, int session_handle,
 731                 struct lttng_ust_object_data *channel_data)
 732 {
 733         struct ustcomm_ust_msg lum;
 734         struct ustcomm_ust_reply lur;
 735         int ret;
 736
 737         if (!channel_data)
 738                 return -EINVAL;
 739
 740         memset(&lum, 0, sizeof(lum));
 741         lum.handle = session_handle;
 742         lum.cmd = LTTNG_UST_CHANNEL;
 743         lum.u.channel.len = channel_data->size;
 744         lum.u.channel.type = channel_data->u.channel.type;
 745         ret = ustcomm_send_app_msg(sock, &lum);
 746         if (ret)
 747                 return ret;
 748
 749         ret = ustctl_send_channel(sock,
 750                         channel_data->u.channel.type,
 751                         channel_data->u.channel.data,
 752                         channel_data->size,
 753                         channel_data->u.channel.wakeup_fd,
 754                         1);
 755         if (ret)
 756                 return ret;
 757         ret = ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 758         if (!ret) {
 759                 if (lur.ret_val >= 0) {
 760                         channel_data->handle = lur.ret_val;
 761                 }
 762         }
 763         return ret;
 764 }
 765
 766 int ustctl_send_stream_to_ust(int sock,
 767                 struct lttng_ust_object_data *channel_data,
 768                 struct lttng_ust_object_data *stream_data)
 769 {
 770         struct ustcomm_ust_msg lum;
 771         struct ustcomm_ust_reply lur;
 772         int ret;
 773
 774         memset(&lum, 0, sizeof(lum));
 775         lum.handle = channel_data->handle;
 776         lum.cmd = LTTNG_UST_STREAM;
 777         lum.u.stream.len = stream_data->size;
 778         lum.u.stream.stream_nr = stream_data->u.stream.stream_nr;
 779         ret = ustcomm_send_app_msg(sock, &lum);
 780         if (ret)
 781                 return ret;
 782
 783         assert(stream_data);
 784         assert(stream_data->type == LTTNG_UST_OBJECT_TYPE_STREAM);
 785
 786         ret = ustctl_send_stream(sock,
 787                         stream_data->u.stream.stream_nr,
 788                         stream_data->size,
 789                         stream_data->u.stream.shm_fd,
 790                         stream_data->u.stream.wakeup_fd, 1);
 791         if (ret)
 792                 return ret;
 793         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 794 }
 795
 796 int ustctl_duplicate_ust_object_data(struct lttng_ust_object_data **dest,
 797                 struct lttng_ust_object_data *src)
 798 {
 799         struct lttng_ust_object_data *obj;
 800         int ret;
 801
 802         if (src->handle != -1) {
 803                 ret = -EINVAL;
 804                 goto error;
 805         }
 806
 807         obj = zmalloc(sizeof(*obj));
 808         if (!obj) {
 809                 ret = -ENOMEM;
 810                 goto error;
 811         }
 812
 813         obj->type = src->type;
 814         obj->handle = src->handle;
 815         obj->size = src->size;
 816
 817         switch (obj->type) {
 818         case LTTNG_UST_OBJECT_TYPE_CHANNEL:
 819         {
 820                 obj->u.channel.type = src->u.channel.type;
 821                 if (src->u.channel.wakeup_fd >= 0) {
 822                         obj->u.channel.wakeup_fd =
 823                                 dup(src->u.channel.wakeup_fd);
 824                         if (obj->u.channel.wakeup_fd < 0) {
 825                                 ret = errno;
 826                                 goto chan_error_wakeup_fd;
 827                         }
 828                 } else {
 829                         obj->u.channel.wakeup_fd =
 830                                 src->u.channel.wakeup_fd;
 831                 }
 832                 obj->u.channel.data = zmalloc(obj->size);
 833                 if (!obj->u.channel.data) {
 834                         ret = -ENOMEM;
 835                         goto chan_error_alloc;
 836                 }
 837                 memcpy(obj->u.channel.data, src->u.channel.data, obj->size);
 838                 break;
 839
 840         chan_error_alloc:
 841                 if (src->u.channel.wakeup_fd >= 0) {
 842                         int closeret;
 843
 844                         closeret = close(obj->u.channel.wakeup_fd);
 845                         if (closeret) {
 846                                 PERROR("close");
 847                         }
 848                 }
 849         chan_error_wakeup_fd:
 850                 goto error_type;
 851
 852         }
 853
 854         case LTTNG_UST_OBJECT_TYPE_STREAM:
 855         {
 856                 obj->u.stream.stream_nr = src->u.stream.stream_nr;
 857                 if (src->u.stream.wakeup_fd >= 0) {
 858                         obj->u.stream.wakeup_fd =
 859                                 dup(src->u.stream.wakeup_fd);
 860                         if (obj->u.stream.wakeup_fd < 0) {
 861                                 ret = errno;
 862                                 goto stream_error_wakeup_fd;
 863                         }
 864                 } else {
 865                         obj->u.stream.wakeup_fd =
 866                                 src->u.stream.wakeup_fd;
 867                 }
 868
 869                 if (src->u.stream.shm_fd >= 0) {
 870                         obj->u.stream.shm_fd =
 871                                 dup(src->u.stream.shm_fd);
 872                         if (obj->u.stream.shm_fd < 0) {
 873                                 ret = errno;
 874                                 goto stream_error_shm_fd;
 875                         }
 876                 } else {
 877                         obj->u.stream.shm_fd =
 878                                 src->u.stream.shm_fd;
 879                 }
 880                 break;
 881
 882         stream_error_shm_fd:
 883                 if (src->u.stream.wakeup_fd >= 0) {
 884                         int closeret;
 885
 886                         closeret = close(obj->u.stream.wakeup_fd);
 887                         if (closeret) {
 888                                 PERROR("close");
 889                         }
 890                 }
 891         stream_error_wakeup_fd:
 892                 goto error_type;
 893         }
 894
 895         default:
 896                 ret = -EINVAL;
 897                 goto error_type;
 898         }
 899
 900         *dest = obj;
 901         return 0;
 902
 903 error_type:
 904         free(obj);
 905 error:
 906         return ret;
 907 }
 908
 909
 910 /* Buffer operations */
 911
 912 struct ustctl_consumer_channel *
 913         ustctl_create_channel(struct ustctl_consumer_channel_attr *attr)
 914 {
 915         struct ustctl_consumer_channel *chan;
 916         const char *transport_name;
 917         struct lttng_transport *transport;
 918
 919         switch (attr->type) {
 920         case LTTNG_UST_CHAN_PER_CPU:
 921                 if (attr->output == LTTNG_UST_MMAP) {
 922                         if (attr->overwrite) {
 923                                 if (attr->read_timer_interval == 0) {
 924                                         transport_name = "relay-overwrite-mmap";
 925                                 } else {
 926                                         transport_name = "relay-overwrite-rt-mmap";
 927                                 }
 928                         } else {
 929                                 if (attr->read_timer_interval == 0) {
 930                                         transport_name = "relay-discard-mmap";
 931                                 } else {
 932                                         transport_name = "relay-discard-rt-mmap";
 933                                 }
 934                         }
 935                 } else {
 936                         return NULL;
 937                 }
 938                 break;
 939         case LTTNG_UST_CHAN_METADATA:
 940                 if (attr->output == LTTNG_UST_MMAP)
 941                         transport_name = "relay-metadata-mmap";
 942                 else
 943                         return NULL;
 944                 break;
 945         default:
 946                 transport_name = "<unknown>";
 947                 return NULL;
 948         }
 949
 950         transport = lttng_transport_find(transport_name);
 951         if (!transport) {
 952                 DBG("LTTng transport %s not found\n",
 953                         transport_name);
 954                 return NULL;
 955         }
 956
 957         chan = zmalloc(sizeof(*chan));
 958         if (!chan)
 959                 return NULL;
 960
 961         chan->chan = transport->ops.channel_create(transport_name, NULL,
 962                         attr->subbuf_size, attr->num_subbuf,
 963                         attr->switch_timer_interval,
 964                         attr->read_timer_interval,
 965                         attr->uuid);
 966         if (!chan->chan) {
 967                 goto chan_error;
 968         }
 969         chan->chan->ops = &transport->ops;
 970         memcpy(&chan->attr, attr, sizeof(chan->attr));
 971         chan->wait_fd = ustctl_channel_get_wait_fd(chan);
 972         chan->wakeup_fd = ustctl_channel_get_wakeup_fd(chan);
 973         return chan;
 974
 975 chan_error:
 976         free(chan);
 977         return NULL;
 978 }
 979
 980 void ustctl_destroy_channel(struct ustctl_consumer_channel *chan)
 981 {
 982         chan->chan->ops->channel_destroy(chan->chan);
 983         free(chan);
 984 }
 985
 986 int ustctl_send_channel_to_sessiond(int sock,
 987                 struct ustctl_consumer_channel *channel)
 988 {
 989         struct shm_object_table *table;
 990
 991         table = channel->chan->handle->table;
 992         if (table->size <= 0)
 993                 return -EINVAL;
 994         return ustctl_send_channel(sock,
 995                         channel->attr.type,
 996                         table->objects[0].memory_map,
 997                         table->objects[0].memory_map_size,
 998                         channel->wakeup_fd,
 999                         0);
1000 }
1001
1002 int ustctl_send_stream_to_sessiond(int sock,
1003                 struct ustctl_consumer_stream *stream)
1004 {
1005         if (!stream)
1006                 return ustctl_send_stream(sock, -1U, -1U, -1, -1, 0);
1007
1008         return ustctl_send_stream(sock,
1009                         stream->cpu,
1010                         stream->memory_map_size,
1011                         stream->shm_fd, stream->wakeup_fd,
1012                         0);
1013 }
1014
1015 int ustctl_write_metadata_to_channel(
1016                 struct ustctl_consumer_channel *channel,
1017                 const char *metadata_str,       /* NOT null-terminated */
1018                 size_t len)                     /* metadata length */
1019 {
1020         struct lttng_ust_lib_ring_buffer_ctx ctx;
1021         struct lttng_channel *chan = channel->chan;
1022         const char *str = metadata_str;
1023         int ret = 0, waitret;
1024         size_t reserve_len, pos;
1025
1026         for (pos = 0; pos < len; pos += reserve_len) {
1027                 reserve_len = min_t(size_t,
1028                                 chan->ops->packet_avail_size(chan->chan, chan->handle),
1029                                 len - pos);
1030                 lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
1031                                          sizeof(char), -1, chan->handle);
1032                 /*
1033                  * We don't care about metadata buffer's records lost
1034                  * count, because we always retry here. Report error if
1035                  * we need to bail out after timeout or being
1036                  * interrupted.
1037                  */
1038                 waitret = wait_cond_interruptible_timeout(
1039                         ({
1040                                 ret = chan->ops->event_reserve(&ctx, 0);
1041                                 ret != -ENOBUFS || !ret;
1042                         }),
1043                         LTTNG_METADATA_TIMEOUT_MSEC);
1044                 if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) {
1045                         DBG("LTTng: Failure to write metadata to buffers (%s)\n",
1046                                 waitret == -EINTR ? "interrupted" :
1047                                         (ret == -ENOBUFS ? "timeout" : "I/O error"));
1048                         if (waitret == -EINTR)
1049                                 ret = waitret;
1050                         goto end;
1051                 }
1052                 chan->ops->event_write(&ctx, &str[pos], reserve_len);
1053                 chan->ops->event_commit(&ctx);
1054         }
1055 end:
1056         return ret;
1057 }
1058
1059 int ustctl_channel_close_wait_fd(struct ustctl_consumer_channel *consumer_chan)
1060 {
1061         struct channel *chan;
1062         int ret;
1063
1064         chan = consumer_chan->chan->chan;
1065         ret = ring_buffer_channel_close_wait_fd(&chan->backend.config,
1066                         chan, chan->handle);
1067         if (!ret)
1068                 consumer_chan->wait_fd = -1;
1069         return ret;
1070 }
1071
1072 int ustctl_channel_close_wakeup_fd(struct ustctl_consumer_channel *consumer_chan)
1073 {
1074         struct channel *chan;
1075         int ret;
1076
1077         chan = consumer_chan->chan->chan;
1078         ret = ring_buffer_channel_close_wakeup_fd(&chan->backend.config,
1079                         chan, chan->handle);
1080         if (!ret)
1081                 consumer_chan->wakeup_fd = -1;
1082         return ret;
1083 }
1084
1085 int ustctl_stream_close_wait_fd(struct ustctl_consumer_stream *stream)
1086 {
1087         struct channel *chan;
1088
1089         chan = stream->chan->chan->chan;
1090         return ring_buffer_stream_close_wait_fd(&chan->backend.config,
1091                         chan, stream->handle, stream->cpu);
1092 }
1093
1094 int ustctl_stream_close_wakeup_fd(struct ustctl_consumer_stream *stream)
1095 {
1096         struct channel *chan;
1097
1098         chan = stream->chan->chan->chan;
1099         return ring_buffer_stream_close_wakeup_fd(&chan->backend.config,
1100                         chan, stream->handle, stream->cpu);
1101 }
1102
1103 struct ustctl_consumer_stream *
1104         ustctl_create_stream(struct ustctl_consumer_channel *channel,
1105                         int cpu)
1106 {
1107         struct ustctl_consumer_stream *stream;
1108         struct lttng_ust_shm_handle *handle;
1109         struct channel *chan;
1110         int shm_fd, wait_fd, wakeup_fd;
1111         uint64_t memory_map_size;
1112         struct lttng_ust_lib_ring_buffer *buf;
1113         int ret;
1114
1115         if (!channel)
1116                 return NULL;
1117         handle = channel->chan->handle;
1118         if (!handle)
1119                 return NULL;
1120
1121         chan = channel->chan->chan;
1122         buf = channel_get_ring_buffer(&chan->backend.config,
1123                 chan, cpu, handle, &shm_fd, &wait_fd,
1124                 &wakeup_fd, &memory_map_size);
1125         if (!buf)
1126                 return NULL;
1127         ret = lib_ring_buffer_open_read(buf, handle);
1128         if (ret)
1129                 return NULL;
1130
1131         stream = zmalloc(sizeof(*stream));
1132         if (!stream)
1133                 goto alloc_error;
1134         stream->handle = handle;
1135         stream->buf = buf;
1136         stream->chan = channel;
1137         stream->shm_fd = shm_fd;
1138         stream->wait_fd = wait_fd;
1139         stream->wakeup_fd = wakeup_fd;
1140         stream->memory_map_size = memory_map_size;
1141         stream->cpu = cpu;
1142         return stream;
1143
1144 alloc_error:
1145         return NULL;
1146 }
1147
1148 void ustctl_destroy_stream(struct ustctl_consumer_stream *stream)
1149 {
1150         struct lttng_ust_lib_ring_buffer *buf;
1151         struct ustctl_consumer_channel *consumer_chan;
1152
1153         assert(stream);
1154         buf = stream->buf;
1155         consumer_chan = stream->chan;
1156         lib_ring_buffer_release_read(buf, consumer_chan->chan->handle);
1157         free(stream);
1158 }
1159
1160 int ustctl_channel_get_wait_fd(struct ustctl_consumer_channel *chan)
1161 {
1162         if (!chan)
1163                 return -EINVAL;
1164         return shm_get_wait_fd(chan->chan->handle,
1165                 &chan->chan->handle->chan._ref);
1166 }
1167
1168 int ustctl_channel_get_wakeup_fd(struct ustctl_consumer_channel *chan)
1169 {
1170         if (!chan)
1171                 return -EINVAL;
1172         return shm_get_wakeup_fd(chan->chan->handle,
1173                 &chan->chan->handle->chan._ref);
1174 }
1175
1176 int ustctl_stream_get_wait_fd(struct ustctl_consumer_stream *stream)
1177 {
1178         struct lttng_ust_lib_ring_buffer *buf;
1179         struct ustctl_consumer_channel *consumer_chan;
1180
1181         if (!stream)
1182                 return -EINVAL;
1183         buf = stream->buf;
1184         consumer_chan = stream->chan;
1185         return shm_get_wait_fd(consumer_chan->chan->handle, &buf->self._ref);
1186 }
1187
1188 int ustctl_stream_get_wakeup_fd(struct ustctl_consumer_stream *stream)
1189 {
1190         struct lttng_ust_lib_ring_buffer *buf;
1191         struct ustctl_consumer_channel *consumer_chan;
1192
1193         if (!stream)
1194                 return -EINVAL;
1195         buf = stream->buf;
1196         consumer_chan = stream->chan;
1197         return shm_get_wakeup_fd(consumer_chan->chan->handle, &buf->self._ref);
1198 }
1199
1200 /* For mmap mode, readable without "get" operation */
1201
1202 void *ustctl_get_mmap_base(struct ustctl_consumer_stream *stream)
1203 {
1204         struct lttng_ust_lib_ring_buffer *buf;
1205         struct ustctl_consumer_channel *consumer_chan;
1206
1207         if (!stream)
1208                 return NULL;
1209         buf = stream->buf;
1210         consumer_chan = stream->chan;
1211         return shmp(consumer_chan->chan->handle, buf->backend.memory_map);
1212 }
1213
1214 /* returns the length to mmap. */
1215 int ustctl_get_mmap_len(struct ustctl_consumer_stream *stream,
1216                 unsigned long *len)
1217 {
1218         struct ustctl_consumer_channel *consumer_chan;
1219         unsigned long mmap_buf_len;
1220         struct channel *chan;
1221
1222         if (!stream)
1223                 return -EINVAL;
1224         consumer_chan = stream->chan;
1225         chan = consumer_chan->chan->chan;
1226         if (chan->backend.config.output != RING_BUFFER_MMAP)
1227                 return -EINVAL;
1228         mmap_buf_len = chan->backend.buf_size;
1229         if (chan->backend.extra_reader_sb)
1230                 mmap_buf_len += chan->backend.subbuf_size;
1231         if (mmap_buf_len > INT_MAX)
1232                 return -EFBIG;
1233         *len = mmap_buf_len;
1234         return 0;
1235 }
1236
1237 /* returns the maximum size for sub-buffers. */
1238 int ustctl_get_max_subbuf_size(struct ustctl_consumer_stream *stream,
1239                 unsigned long *len)
1240 {
1241         struct ustctl_consumer_channel *consumer_chan;
1242         struct channel *chan;
1243
1244         if (!stream)
1245                 return -EINVAL;
1246         consumer_chan = stream->chan;
1247         chan = consumer_chan->chan->chan;
1248         *len = chan->backend.subbuf_size;
1249         return 0;
1250 }
1251
1252 /*
1253  * For mmap mode, operate on the current packet (between get/put or
1254  * get_next/put_next).
1255  */
1256
1257 /* returns the offset of the subbuffer belonging to the mmap reader. */
1258 int ustctl_get_mmap_read_offset(struct ustctl_consumer_stream *stream,
1259                 unsigned long *off)
1260 {
1261         struct channel *chan;
1262         unsigned long sb_bindex;
1263         struct lttng_ust_lib_ring_buffer *buf;
1264         struct ustctl_consumer_channel *consumer_chan;
1265
1266         if (!stream)
1267                 return -EINVAL;
1268         buf = stream->buf;
1269         consumer_chan = stream->chan;
1270         chan = consumer_chan->chan->chan;
1271         if (chan->backend.config.output != RING_BUFFER_MMAP)
1272                 return -EINVAL;
1273         sb_bindex = subbuffer_id_get_index(&chan->backend.config,
1274                                         buf->backend.buf_rsb.id);
1275         *off = shmp(consumer_chan->chan->handle,
1276                 shmp_index(consumer_chan->chan->handle, buf->backend.array, sb_bindex)->shmp)->mmap_offset;
1277         return 0;
1278 }
1279
1280 /* returns the size of the current sub-buffer, without padding (for mmap). */
1281 int ustctl_get_subbuf_size(struct ustctl_consumer_stream *stream,
1282                 unsigned long *len)
1283 {
1284         struct ustctl_consumer_channel *consumer_chan;
1285         struct channel *chan;
1286         struct lttng_ust_lib_ring_buffer *buf;
1287
1288         if (!stream)
1289                 return -EINVAL;
1290
1291         buf = stream->buf;
1292         consumer_chan = stream->chan;
1293         chan = consumer_chan->chan->chan;
1294         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
1295                 consumer_chan->chan->handle);
1296         return 0;
1297 }
1298
1299 /* returns the size of the current sub-buffer, without padding (for mmap). */
1300 int ustctl_get_padded_subbuf_size(struct ustctl_consumer_stream *stream,
1301                 unsigned long *len)
1302 {
1303         struct ustctl_consumer_channel *consumer_chan;
1304         struct channel *chan;
1305         struct lttng_ust_lib_ring_buffer *buf;
1306
1307         if (!stream)
1308                 return -EINVAL;
1309         buf = stream->buf;
1310         consumer_chan = stream->chan;
1311         chan = consumer_chan->chan->chan;
1312         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
1313                 consumer_chan->chan->handle);
1314         *len = PAGE_ALIGN(*len);
1315         return 0;
1316 }
1317
1318 /* Get exclusive read access to the next sub-buffer that can be read. */
1319 int ustctl_get_next_subbuf(struct ustctl_consumer_stream *stream)
1320 {
1321         struct lttng_ust_lib_ring_buffer *buf;
1322         struct ustctl_consumer_channel *consumer_chan;
1323
1324         if (!stream)
1325                 return -EINVAL;
1326         buf = stream->buf;
1327         consumer_chan = stream->chan;
1328         return lib_ring_buffer_get_next_subbuf(buf,
1329                         consumer_chan->chan->handle);
1330 }
1331
1332
1333 /* Release exclusive sub-buffer access, move consumer forward. */
1334 int ustctl_put_next_subbuf(struct ustctl_consumer_stream *stream)
1335 {
1336         struct lttng_ust_lib_ring_buffer *buf;
1337         struct ustctl_consumer_channel *consumer_chan;
1338
1339         if (!stream)
1340                 return -EINVAL;
1341         buf = stream->buf;
1342         consumer_chan = stream->chan;
1343         lib_ring_buffer_put_next_subbuf(buf, consumer_chan->chan->handle);
1344         return 0;
1345 }
1346
1347 /* snapshot */
1348
1349 /* Get a snapshot of the current ring buffer producer and consumer positions */
1350 int ustctl_snapshot(struct ustctl_consumer_stream *stream)
1351 {
1352         struct lttng_ust_lib_ring_buffer *buf;
1353         struct ustctl_consumer_channel *consumer_chan;
1354
1355         if (!stream)
1356                 return -EINVAL;
1357         buf = stream->buf;
1358         consumer_chan = stream->chan;
1359         return lib_ring_buffer_snapshot(buf, &buf->cons_snapshot,
1360                         &buf->prod_snapshot, consumer_chan->chan->handle);
1361 }
1362
1363 /* Get the consumer position (iteration start) */
1364 int ustctl_snapshot_get_consumed(struct ustctl_consumer_stream *stream,
1365                 unsigned long *pos)
1366 {
1367         struct lttng_ust_lib_ring_buffer *buf;
1368
1369         if (!stream)
1370                 return -EINVAL;
1371         buf = stream->buf;
1372         *pos = buf->cons_snapshot;
1373         return 0;
1374 }
1375
1376 /* Get the producer position (iteration end) */
1377 int ustctl_snapshot_get_produced(struct ustctl_consumer_stream *stream,
1378                 unsigned long *pos)
1379 {
1380         struct lttng_ust_lib_ring_buffer *buf;
1381
1382         if (!stream)
1383                 return -EINVAL;
1384         buf = stream->buf;
1385         *pos = buf->prod_snapshot;
1386         return 0;
1387 }
1388
1389 /* Get exclusive read access to the specified sub-buffer position */
1390 int ustctl_get_subbuf(struct ustctl_consumer_stream *stream,
1391                 unsigned long *pos)
1392 {
1393         struct lttng_ust_lib_ring_buffer *buf;
1394         struct ustctl_consumer_channel *consumer_chan;
1395
1396         if (!stream)
1397                 return -EINVAL;
1398         buf = stream->buf;
1399         consumer_chan = stream->chan;
1400         return lib_ring_buffer_get_subbuf(buf, *pos,
1401                         consumer_chan->chan->handle);
1402 }
1403
1404 /* Release exclusive sub-buffer access */
1405 int ustctl_put_subbuf(struct ustctl_consumer_stream *stream)
1406 {
1407         struct lttng_ust_lib_ring_buffer *buf;
1408         struct ustctl_consumer_channel *consumer_chan;
1409
1410         if (!stream)
1411                 return -EINVAL;
1412         buf = stream->buf;
1413         consumer_chan = stream->chan;
1414         lib_ring_buffer_put_subbuf(buf, consumer_chan->chan->handle);
1415         return 0;
1416 }
1417
1418 void ustctl_flush_buffer(struct ustctl_consumer_stream *stream,
1419                 int producer_active)
1420 {
1421         struct lttng_ust_lib_ring_buffer *buf;
1422         struct ustctl_consumer_channel *consumer_chan;
1423
1424         assert(stream);
1425         buf = stream->buf;
1426         consumer_chan = stream->chan;
1427         lib_ring_buffer_switch_slow(buf,
1428                 producer_active ? SWITCH_ACTIVE : SWITCH_FLUSH,
1429                 consumer_chan->chan->handle);
1430 }
1431
1432 /*
1433  * Returns 0 on success, negative error value on error.
1434  */
1435 int ustctl_recv_reg_msg(int sock,
1436         enum ustctl_socket_type *type,
1437         uint32_t *major,
1438         uint32_t *minor,
1439         uint32_t *pid,
1440         uint32_t *ppid,
1441         uint32_t *uid,
1442         uint32_t *gid,
1443         uint32_t *bits_per_long,
1444         uint32_t *uint8_t_alignment,
1445         uint32_t *uint16_t_alignment,
1446         uint32_t *uint32_t_alignment,
1447         uint32_t *uint64_t_alignment,
1448         uint32_t *long_alignment,
1449         int *byte_order,
1450         char *name)
1451 {
1452         ssize_t len;
1453         struct ustctl_reg_msg reg_msg;
1454
1455         len = ustcomm_recv_unix_sock(sock, &reg_msg, sizeof(reg_msg));
1456         if (len > 0 && len != sizeof(reg_msg))
1457                 return -EIO;
1458         if (len == 0)
1459                 return -EPIPE;
1460         if (len < 0)
1461                 return len;
1462
1463         if (reg_msg.magic == LTTNG_UST_COMM_MAGIC) {
1464                 *byte_order = BYTE_ORDER == BIG_ENDIAN ?
1465                                 BIG_ENDIAN : LITTLE_ENDIAN;
1466         } else if (reg_msg.magic == bswap_32(LTTNG_UST_COMM_MAGIC)) {
1467                 *byte_order = BYTE_ORDER == BIG_ENDIAN ?
1468                                 LITTLE_ENDIAN : BIG_ENDIAN;
1469         } else {
1470                 return -LTTNG_UST_ERR_INVAL_MAGIC;
1471         }
1472         switch (reg_msg.socket_type) {
1473         case 0: *type = USTCTL_SOCKET_CMD;
1474                 break;
1475         case 1: *type = USTCTL_SOCKET_NOTIFY;
1476                 break;
1477         default:
1478                 return -LTTNG_UST_ERR_INVAL_SOCKET_TYPE;
1479         }
1480         *major = reg_msg.major;
1481         *minor = reg_msg.minor;
1482         *pid = reg_msg.pid;
1483         *ppid = reg_msg.ppid;
1484         *uid = reg_msg.uid;
1485         *gid = reg_msg.gid;
1486         *bits_per_long = reg_msg.bits_per_long;
1487         *uint8_t_alignment = reg_msg.uint8_t_alignment;
1488         *uint16_t_alignment = reg_msg.uint16_t_alignment;
1489         *uint32_t_alignment = reg_msg.uint32_t_alignment;
1490         *uint64_t_alignment = reg_msg.uint64_t_alignment;
1491         *long_alignment = reg_msg.long_alignment;
1492         memcpy(name, reg_msg.name, LTTNG_UST_ABI_PROCNAME_LEN);
1493         if (reg_msg.major != LTTNG_UST_ABI_MAJOR_VERSION) {
1494                 return -LTTNG_UST_ERR_UNSUP_MAJOR;
1495         }
1496
1497         return 0;
1498 }
1499
1500 int ustctl_recv_notify(int sock, enum ustctl_notify_cmd *notify_cmd)
1501 {
1502         struct ustcomm_notify_hdr header;
1503         ssize_t len;
1504
1505         len = ustcomm_recv_unix_sock(sock, &header, sizeof(header));
1506         if (len > 0 && len != sizeof(header))
1507                 return -EIO;
1508         if (len == 0)
1509                 return -EPIPE;
1510         if (len < 0)
1511                 return len;
1512         switch (header.notify_cmd) {
1513         case 0:
1514                 *notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
1515                 break;
1516         case 1:
1517                 *notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
1518                 break;
1519         default:
1520                 return -EINVAL;
1521         }
1522         return 0;
1523 }
1524
1525 /*
1526  * Returns 0 on success, negative error value on error.
1527  */
1528 int ustctl_recv_register_event(int sock,
1529         int *session_objd,
1530         int *channel_objd,
1531         char *event_name,
1532         int *loglevel,
1533         char **signature,
1534         size_t *nr_fields,
1535         struct ustctl_field **fields,
1536         char **model_emf_uri)
1537 {
1538         ssize_t len;
1539         struct ustcomm_notify_event_msg msg;
1540         size_t signature_len, fields_len, model_emf_uri_len;
1541         char *a_sign = NULL, *a_model_emf_uri = NULL;
1542         struct ustctl_field *a_fields = NULL;
1543
1544         len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
1545         if (len > 0 && len != sizeof(msg))
1546                 return -EIO;
1547         if (len == 0)
1548                 return -EPIPE;
1549         if (len < 0)
1550                 return len;
1551
1552         *session_objd = msg.session_objd;
1553         *channel_objd = msg.channel_objd;
1554         strncpy(event_name, msg.event_name, LTTNG_UST_SYM_NAME_LEN);
1555         event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
1556         *loglevel = msg.loglevel;
1557         signature_len = msg.signature_len;
1558         fields_len = msg.fields_len;
1559
1560         if (fields_len % sizeof(*a_fields) != 0) {
1561                 return -EINVAL;
1562         }
1563
1564         model_emf_uri_len = msg.model_emf_uri_len;
1565
1566         /* recv signature. contains at least \0. */
1567         a_sign = zmalloc(signature_len);
1568         if (!a_sign)
1569                 return -ENOMEM;
1570         len = ustcomm_recv_unix_sock(sock, a_sign, signature_len);
1571         if (len > 0 && len != signature_len) {
1572                 len = -EIO;
1573                 goto signature_error;
1574         }
1575         if (len == 0) {
1576                 len = -EPIPE;
1577                 goto signature_error;
1578         }
1579         if (len < 0) {
1580                 goto signature_error;
1581         }
1582         /* Enforce end of string */
1583         signature[signature_len - 1] = '\0';
1584
1585         /* recv fields */
1586         if (fields_len) {
1587                 a_fields = zmalloc(fields_len);
1588                 if (!a_fields) {
1589                         len = -ENOMEM;
1590                         goto signature_error;
1591                 }
1592                 len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
1593                 if (len > 0 && len != fields_len) {
1594                         len = -EIO;
1595                         goto fields_error;
1596                 }
1597                 if (len == 0) {
1598                         len = -EPIPE;
1599                         goto fields_error;
1600                 }
1601                 if (len < 0) {
1602                         goto fields_error;
1603                 }
1604         }
1605
1606         if (model_emf_uri_len) {
1607                 /* recv model_emf_uri_len */
1608                 a_model_emf_uri = zmalloc(model_emf_uri_len);
1609                 if (!a_model_emf_uri) {
1610                         len = -ENOMEM;
1611                         goto fields_error;
1612                 }
1613                 len = ustcomm_recv_unix_sock(sock, a_model_emf_uri,
1614                                 model_emf_uri_len);
1615                 if (len > 0 && len != model_emf_uri_len) {
1616                         len = -EIO;
1617                         goto model_error;
1618                 }
1619                 if (len == 0) {
1620                         len = -EPIPE;
1621                         goto model_error;
1622                 }
1623                 if (len < 0) {
1624                         goto model_error;
1625                 }
1626                 /* Enforce end of string */
1627                 a_model_emf_uri[model_emf_uri_len - 1] = '\0';
1628         }
1629
1630         *signature = a_sign;
1631         *nr_fields = fields_len / sizeof(*a_fields);
1632         *fields = a_fields;
1633         *model_emf_uri = a_model_emf_uri;
1634
1635         return 0;
1636
1637 model_error:
1638         free(a_model_emf_uri);
1639 fields_error:
1640         free(a_fields);
1641 signature_error:
1642         free(a_sign);
1643         return len;
1644 }
1645
1646 /*
1647  * Returns 0 on success, negative error value on error.
1648  */
1649 int ustctl_reply_register_event(int sock,
1650         uint32_t id,
1651         int ret_code)
1652 {
1653         ssize_t len;
1654         struct {
1655                 struct ustcomm_notify_hdr header;
1656                 struct ustcomm_notify_event_reply r;
1657         } reply;
1658
1659         memset(&reply, 0, sizeof(reply));
1660         reply.header.notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
1661         reply.r.ret_code = ret_code;
1662         reply.r.event_id = id;
1663         len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
1664         if (len > 0 && len != sizeof(reply))
1665                 return -EIO;
1666         if (len < 0)
1667                 return len;
1668         return 0;
1669 }
1670
1671 /*
1672  * Returns 0 on success, negative UST or system error value on error.
1673  */
1674 int ustctl_recv_register_channel(int sock,
1675         int *session_objd,              /* session descriptor (output) */
1676         int *channel_objd,              /* channel descriptor (output) */
1677         size_t *nr_fields,
1678         struct ustctl_field **fields)
1679 {
1680         ssize_t len;
1681         struct ustcomm_notify_channel_msg msg;
1682         size_t fields_len;
1683         struct ustctl_field *a_fields;
1684
1685         len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
1686         if (len > 0 && len != sizeof(msg))
1687                 return -EIO;
1688         if (len == 0)
1689                 return -EPIPE;
1690         if (len < 0)
1691                 return len;
1692
1693         *session_objd = msg.session_objd;
1694         *channel_objd = msg.channel_objd;
1695         fields_len = msg.ctx_fields_len;
1696
1697         if (fields_len % sizeof(*a_fields) != 0) {
1698                 return -EINVAL;
1699         }
1700
1701         /* recv fields */
1702         if (fields_len) {
1703                 a_fields = zmalloc(fields_len);
1704                 if (!a_fields) {
1705                         len = -ENOMEM;
1706                         goto alloc_error;
1707                 }
1708                 len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
1709                 if (len > 0 && len != fields_len) {
1710                         len = -EIO;
1711                         goto fields_error;
1712                 }
1713                 if (len == 0) {
1714                         len = -EPIPE;
1715                         goto fields_error;
1716                 }
1717                 if (len < 0) {
1718                         goto fields_error;
1719                 }
1720                 *fields = a_fields;
1721         } else {
1722                 *fields = NULL;
1723         }
1724         *nr_fields = fields_len / sizeof(*a_fields);
1725         return 0;
1726
1727 fields_error:
1728         free(a_fields);
1729 alloc_error:
1730         return len;
1731 }
1732
1733 /*
1734  * Returns 0 on success, negative error value on error.
1735  */
1736 int ustctl_reply_register_channel(int sock,
1737         uint32_t chan_id,
1738         enum ustctl_channel_header header_type,
1739         int ret_code)
1740 {
1741         ssize_t len;
1742         struct {
1743                 struct ustcomm_notify_hdr header;
1744                 struct ustcomm_notify_channel_reply r;
1745         } reply;
1746
1747         memset(&reply, 0, sizeof(reply));
1748         reply.header.notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
1749         reply.r.ret_code = ret_code;
1750         reply.r.chan_id = chan_id;
1751         switch (header_type) {
1752         case USTCTL_CHANNEL_HEADER_COMPACT:
1753                 reply.r.header_type = 1;
1754                 break;
1755         case USTCTL_CHANNEL_HEADER_LARGE:
1756                 reply.r.header_type = 2;
1757                 break;
1758         default:
1759                 reply.r.header_type = 0;
1760                 break;
1761         }
1762         len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
1763         if (len > 0 && len != sizeof(reply))
1764                 return -EIO;
1765         if (len < 0)
1766                 return len;
1767         return 0;
1768 }
1769
1770 static __attribute__((constructor))
1771 void ustctl_init(void)
1772 {
1773         init_usterr();
1774         lttng_ring_buffer_metadata_client_init();
1775         lttng_ring_buffer_client_overwrite_init();
1776         lttng_ring_buffer_client_overwrite_rt_init();
1777         lttng_ring_buffer_client_discard_init();
1778         lttng_ring_buffer_client_discard_rt_init();
1779         lib_ringbuffer_signal_init();
1780 }
1781
1782 static __attribute__((destructor))
1783 void ustctl_exit(void)
1784 {
1785         lttng_ring_buffer_client_discard_rt_exit();
1786         lttng_ring_buffer_client_discard_exit();
1787         lttng_ring_buffer_client_overwrite_rt_exit();
1788         lttng_ring_buffer_client_overwrite_exit();
1789         lttng_ring_buffer_metadata_client_exit();
1790 }