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-config.h>
  22 #include <lttng/ust-ctl.h>
  23 #include <lttng/ust-abi.h>
  24 #include <lttng/ust-events.h>
  25 #include <sys/mman.h>
  26 #include <byteswap.h>
  27
  28 #include <usterr-signal-safe.h>
  29 #include <ust-comm.h>
  30 #include <helper.h>
  31
  32 #include "../libringbuffer/backend.h"
  33 #include "../libringbuffer/frontend.h"
  34 #include "../liblttng-ust/wait.h"
  35 #include "../liblttng-ust/lttng-rb-clients.h"
  36 #include "../liblttng-ust/clock.h"
  37 #include "../liblttng-ust/getenv.h"
  38
  39 /*
  40  * Number of milliseconds to retry before failing metadata writes on
  41  * buffer full condition. (10 seconds)
  42  */
  43 #define LTTNG_METADATA_TIMEOUT_MSEC     10000
  44
  45 /*
  46  * Channel representation within consumer.
  47  */
  48 struct ustctl_consumer_channel {
  49         struct lttng_channel *chan;             /* lttng channel buffers */
  50
  51         /* initial attributes */
  52         struct ustctl_consumer_channel_attr attr;
  53         int wait_fd;                            /* monitor close() */
  54         int wakeup_fd;                          /* monitor close() */
  55 };
  56
  57 /*
  58  * Stream representation within consumer.
  59  */
  60 struct ustctl_consumer_stream {
  61         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
  62         struct lttng_ust_lib_ring_buffer *buf;
  63         struct ustctl_consumer_channel *chan;
  64         int shm_fd, wait_fd, wakeup_fd;
  65         int cpu;
  66         uint64_t memory_map_size;
  67 };
  68
  69 extern void lttng_ring_buffer_client_overwrite_init(void);
  70 extern void lttng_ring_buffer_client_overwrite_rt_init(void);
  71 extern void lttng_ring_buffer_client_discard_init(void);
  72 extern void lttng_ring_buffer_client_discard_rt_init(void);
  73 extern void lttng_ring_buffer_metadata_client_init(void);
  74 extern void lttng_ring_buffer_client_overwrite_exit(void);
  75 extern void lttng_ring_buffer_client_overwrite_rt_exit(void);
  76 extern void lttng_ring_buffer_client_discard_exit(void);
  77 extern void lttng_ring_buffer_client_discard_rt_exit(void);
  78 extern void lttng_ring_buffer_metadata_client_exit(void);
  79
  80 int ustctl_release_handle(int sock, int handle)
  81 {
  82         struct ustcomm_ust_msg lum;
  83         struct ustcomm_ust_reply lur;
  84
  85         if (sock < 0 || handle < 0)
  86                 return 0;
  87         memset(&lum, 0, sizeof(lum));
  88         lum.handle = handle;
  89         lum.cmd = LTTNG_UST_RELEASE;
  90         return ustcomm_send_app_cmd(sock, &lum, &lur);
  91 }
  92
  93 /*
  94  * If sock is negative, it means we don't have to notify the other side
  95  * (e.g. application has already vanished).
  96  */
  97 int ustctl_release_object(int sock, struct lttng_ust_object_data *data)
  98 {
  99         int ret;
 100
 101         if (!data)
 102                 return -EINVAL;
 103
 104         switch (data->type) {
 105         case LTTNG_UST_OBJECT_TYPE_CHANNEL:
 106                 if (data->u.channel.wakeup_fd >= 0) {
 107                         ret = close(data->u.channel.wakeup_fd);
 108                         if (ret < 0) {
 109                                 ret = -errno;
 110                                 return ret;
 111                         }
 112                         data->u.channel.wakeup_fd = -1;
 113                 }
 114                 free(data->u.channel.data);
 115                 data->u.channel.data = NULL;
 116                 break;
 117         case LTTNG_UST_OBJECT_TYPE_STREAM:
 118                 if (data->u.stream.shm_fd >= 0) {
 119                         ret = close(data->u.stream.shm_fd);
 120                         if (ret < 0) {
 121                                 ret = -errno;
 122                                 return ret;
 123                         }
 124                         data->u.stream.shm_fd = -1;
 125                 }
 126                 if (data->u.stream.wakeup_fd >= 0) {
 127                         ret = close(data->u.stream.wakeup_fd);
 128                         if (ret < 0) {
 129                                 ret = -errno;
 130                                 return ret;
 131                         }
 132                         data->u.stream.wakeup_fd = -1;
 133                 }
 134                 break;
 135         case LTTNG_UST_OBJECT_TYPE_EVENT:
 136         case LTTNG_UST_OBJECT_TYPE_CONTEXT:
 137                 break;
 138         default:
 139                 assert(0);
 140         }
 141         return ustctl_release_handle(sock, data->handle);
 142 }
 143
 144 /*
 145  * Send registration done packet to the application.
 146  */
 147 int ustctl_register_done(int sock)
 148 {
 149         struct ustcomm_ust_msg lum;
 150         struct ustcomm_ust_reply lur;
 151         int ret;
 152
 153         DBG("Sending register done command to %d", sock);
 154         memset(&lum, 0, sizeof(lum));
 155         lum.handle = LTTNG_UST_ROOT_HANDLE;
 156         lum.cmd = LTTNG_UST_REGISTER_DONE;
 157         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 158         if (ret)
 159                 return ret;
 160         return 0;
 161 }
 162
 163 /*
 164  * returns session handle.
 165  */
 166 int ustctl_create_session(int sock)
 167 {
 168         struct ustcomm_ust_msg lum;
 169         struct ustcomm_ust_reply lur;
 170         int ret, session_handle;
 171
 172         /* Create session */
 173         memset(&lum, 0, sizeof(lum));
 174         lum.handle = LTTNG_UST_ROOT_HANDLE;
 175         lum.cmd = LTTNG_UST_SESSION;
 176         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 177         if (ret)
 178                 return ret;
 179         session_handle = lur.ret_val;
 180         DBG("received session handle %u", session_handle);
 181         return session_handle;
 182 }
 183
 184 int ustctl_create_event(int sock, struct lttng_ust_event *ev,
 185                 struct lttng_ust_object_data *channel_data,
 186                 struct lttng_ust_object_data **_event_data)
 187 {
 188         struct ustcomm_ust_msg lum;
 189         struct ustcomm_ust_reply lur;
 190         struct lttng_ust_object_data *event_data;
 191         int ret;
 192
 193         if (!channel_data || !_event_data)
 194                 return -EINVAL;
 195
 196         event_data = zmalloc(sizeof(*event_data));
 197         if (!event_data)
 198                 return -ENOMEM;
 199         event_data->type = LTTNG_UST_OBJECT_TYPE_EVENT;
 200         memset(&lum, 0, sizeof(lum));
 201         lum.handle = channel_data->handle;
 202         lum.cmd = LTTNG_UST_EVENT;
 203         strncpy(lum.u.event.name, ev->name,
 204                 LTTNG_UST_SYM_NAME_LEN);
 205         lum.u.event.instrumentation = ev->instrumentation;
 206         lum.u.event.loglevel_type = ev->loglevel_type;
 207         lum.u.event.loglevel = ev->loglevel;
 208         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 209         if (ret) {
 210                 free(event_data);
 211                 return ret;
 212         }
 213         event_data->handle = lur.ret_val;
 214         DBG("received event handle %u", event_data->handle);
 215         *_event_data = event_data;
 216         return 0;
 217 }
 218
 219 int ustctl_add_context(int sock, struct lttng_ust_context_attr *ctx,
 220                 struct lttng_ust_object_data *obj_data,
 221                 struct lttng_ust_object_data **_context_data)
 222 {
 223         struct ustcomm_ust_msg lum;
 224         struct ustcomm_ust_reply lur;
 225         struct lttng_ust_object_data *context_data = NULL;
 226         char *buf = NULL;
 227         size_t len;
 228         int ret;
 229
 230         if (!obj_data || !_context_data) {
 231                 ret = -EINVAL;
 232                 goto end;
 233         }
 234
 235         context_data = zmalloc(sizeof(*context_data));
 236         if (!context_data) {
 237                 ret = -ENOMEM;
 238                 goto end;
 239         }
 240         context_data->type = LTTNG_UST_OBJECT_TYPE_CONTEXT;
 241         memset(&lum, 0, sizeof(lum));
 242         lum.handle = obj_data->handle;
 243         lum.cmd = LTTNG_UST_CONTEXT;
 244
 245         lum.u.context.ctx = ctx->ctx;
 246         switch (ctx->ctx) {
 247         case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
 248                 lum.u.context.u.perf_counter = ctx->u.perf_counter;
 249                 break;
 250         case LTTNG_UST_CONTEXT_APP_CONTEXT:
 251         {
 252                 size_t provider_name_len = strlen(
 253                                 ctx->u.app_ctx.provider_name) + 1;
 254                 size_t ctx_name_len = strlen(ctx->u.app_ctx.ctx_name) + 1;
 255
 256                 lum.u.context.u.app_ctx.provider_name_len = provider_name_len;
 257                 lum.u.context.u.app_ctx.ctx_name_len = ctx_name_len;
 258
 259                 len = provider_name_len + ctx_name_len;
 260                 buf = zmalloc(len);
 261                 if (!buf) {
 262                         ret = -ENOMEM;
 263                         goto end;
 264                 }
 265                 memcpy(buf, ctx->u.app_ctx.provider_name,
 266                                 provider_name_len);
 267                 memcpy(buf + provider_name_len, ctx->u.app_ctx.ctx_name,
 268                                 ctx_name_len);
 269                 break;
 270         }
 271         default:
 272                 break;
 273         }
 274         ret = ustcomm_send_app_msg(sock, &lum);
 275         if (ret)
 276                 goto end;
 277         if (buf) {
 278                 /* send var len ctx_name */
 279                 ret = ustcomm_send_unix_sock(sock, buf, len);
 280                 if (ret < 0) {
 281                         goto end;
 282                 }
 283                 if (ret != len) {
 284                         ret = -EINVAL;
 285                         goto end;
 286                 }
 287         }
 288         ret = ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 289         if (ret < 0) {
 290                 goto end;
 291         }
 292         context_data->handle = -1;
 293         DBG("Context created successfully");
 294         *_context_data = context_data;
 295         context_data = NULL;
 296 end:
 297         free(context_data);
 298         free(buf);
 299         return ret;
 300 }
 301
 302 int ustctl_set_filter(int sock, struct lttng_ust_filter_bytecode *bytecode,
 303                 struct lttng_ust_object_data *obj_data)
 304 {
 305         struct ustcomm_ust_msg lum;
 306         struct ustcomm_ust_reply lur;
 307         int ret;
 308
 309         if (!obj_data)
 310                 return -EINVAL;
 311
 312         memset(&lum, 0, sizeof(lum));
 313         lum.handle = obj_data->handle;
 314         lum.cmd = LTTNG_UST_FILTER;
 315         lum.u.filter.data_size = bytecode->len;
 316         lum.u.filter.reloc_offset = bytecode->reloc_offset;
 317         lum.u.filter.seqnum = bytecode->seqnum;
 318
 319         ret = ustcomm_send_app_msg(sock, &lum);
 320         if (ret)
 321                 return ret;
 322         /* send var len bytecode */
 323         ret = ustcomm_send_unix_sock(sock, bytecode->data,
 324                                 bytecode->len);
 325         if (ret < 0) {
 326                 return ret;
 327         }
 328         if (ret != bytecode->len)
 329                 return -EINVAL;
 330         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 331 }
 332
 333 int ustctl_set_exclusion(int sock, struct lttng_ust_event_exclusion *exclusion,
 334                 struct lttng_ust_object_data *obj_data)
 335 {
 336         struct ustcomm_ust_msg lum;
 337         struct ustcomm_ust_reply lur;
 338         int ret;
 339
 340         if (!obj_data) {
 341                 return -EINVAL;
 342         }
 343
 344         memset(&lum, 0, sizeof(lum));
 345         lum.handle = obj_data->handle;
 346         lum.cmd = LTTNG_UST_EXCLUSION;
 347         lum.u.exclusion.count = exclusion->count;
 348
 349         ret = ustcomm_send_app_msg(sock, &lum);
 350         if (ret) {
 351                 return ret;
 352         }
 353
 354         /* send var len exclusion names */
 355         ret = ustcomm_send_unix_sock(sock,
 356                         exclusion->names,
 357                         exclusion->count * LTTNG_UST_SYM_NAME_LEN);
 358         if (ret < 0) {
 359                 return ret;
 360         }
 361         if (ret != exclusion->count * LTTNG_UST_SYM_NAME_LEN) {
 362                 return -EINVAL;
 363         }
 364         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 365 }
 366
 367 /* Enable event, channel and session ioctl */
 368 int ustctl_enable(int sock, struct lttng_ust_object_data *object)
 369 {
 370         struct ustcomm_ust_msg lum;
 371         struct ustcomm_ust_reply lur;
 372         int ret;
 373
 374         if (!object)
 375                 return -EINVAL;
 376
 377         memset(&lum, 0, sizeof(lum));
 378         lum.handle = object->handle;
 379         lum.cmd = LTTNG_UST_ENABLE;
 380         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 381         if (ret)
 382                 return ret;
 383         DBG("enabled handle %u", object->handle);
 384         return 0;
 385 }
 386
 387 /* Disable event, channel and session ioctl */
 388 int ustctl_disable(int sock, struct lttng_ust_object_data *object)
 389 {
 390         struct ustcomm_ust_msg lum;
 391         struct ustcomm_ust_reply lur;
 392         int ret;
 393
 394         if (!object)
 395                 return -EINVAL;
 396
 397         memset(&lum, 0, sizeof(lum));
 398         lum.handle = object->handle;
 399         lum.cmd = LTTNG_UST_DISABLE;
 400         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 401         if (ret)
 402                 return ret;
 403         DBG("disable handle %u", object->handle);
 404         return 0;
 405 }
 406
 407 int ustctl_start_session(int sock, int handle)
 408 {
 409         struct lttng_ust_object_data obj;
 410
 411         obj.handle = handle;
 412         return ustctl_enable(sock, &obj);
 413 }
 414
 415 int ustctl_stop_session(int sock, int handle)
 416 {
 417         struct lttng_ust_object_data obj;
 418
 419         obj.handle = handle;
 420         return ustctl_disable(sock, &obj);
 421 }
 422
 423 int ustctl_tracepoint_list(int sock)
 424 {
 425         struct ustcomm_ust_msg lum;
 426         struct ustcomm_ust_reply lur;
 427         int ret, tp_list_handle;
 428
 429         memset(&lum, 0, sizeof(lum));
 430         lum.handle = LTTNG_UST_ROOT_HANDLE;
 431         lum.cmd = LTTNG_UST_TRACEPOINT_LIST;
 432         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 433         if (ret)
 434                 return ret;
 435         tp_list_handle = lur.ret_val;
 436         DBG("received tracepoint list handle %u", tp_list_handle);
 437         return tp_list_handle;
 438 }
 439
 440 int ustctl_tracepoint_list_get(int sock, int tp_list_handle,
 441                 struct lttng_ust_tracepoint_iter *iter)
 442 {
 443         struct ustcomm_ust_msg lum;
 444         struct ustcomm_ust_reply lur;
 445         int ret;
 446
 447         if (!iter)
 448                 return -EINVAL;
 449
 450         memset(&lum, 0, sizeof(lum));
 451         lum.handle = tp_list_handle;
 452         lum.cmd = LTTNG_UST_TRACEPOINT_LIST_GET;
 453         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 454         if (ret)
 455                 return ret;
 456         DBG("received tracepoint list entry name %s loglevel %d",
 457                 lur.u.tracepoint.name,
 458                 lur.u.tracepoint.loglevel);
 459         memcpy(iter, &lur.u.tracepoint, sizeof(*iter));
 460         return 0;
 461 }
 462
 463 int ustctl_tracepoint_field_list(int sock)
 464 {
 465         struct ustcomm_ust_msg lum;
 466         struct ustcomm_ust_reply lur;
 467         int ret, tp_field_list_handle;
 468
 469         memset(&lum, 0, sizeof(lum));
 470         lum.handle = LTTNG_UST_ROOT_HANDLE;
 471         lum.cmd = LTTNG_UST_TRACEPOINT_FIELD_LIST;
 472         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 473         if (ret)
 474                 return ret;
 475         tp_field_list_handle = lur.ret_val;
 476         DBG("received tracepoint field list handle %u", tp_field_list_handle);
 477         return tp_field_list_handle;
 478 }
 479
 480 int ustctl_tracepoint_field_list_get(int sock, int tp_field_list_handle,
 481                 struct lttng_ust_field_iter *iter)
 482 {
 483         struct ustcomm_ust_msg lum;
 484         struct ustcomm_ust_reply lur;
 485         int ret;
 486         ssize_t len;
 487
 488         if (!iter)
 489                 return -EINVAL;
 490
 491         memset(&lum, 0, sizeof(lum));
 492         lum.handle = tp_field_list_handle;
 493         lum.cmd = LTTNG_UST_TRACEPOINT_FIELD_LIST_GET;
 494         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 495         if (ret)
 496                 return ret;
 497         len = ustcomm_recv_unix_sock(sock, iter, sizeof(*iter));
 498         if (len != sizeof(*iter)) {
 499                 return -EINVAL;
 500         }
 501         DBG("received tracepoint field list entry event_name %s event_loglevel %d field_name %s field_type %d",
 502                 iter->event_name,
 503                 iter->loglevel,
 504                 iter->field_name,
 505                 iter->type);
 506         return 0;
 507 }
 508
 509 int ustctl_tracer_version(int sock, struct lttng_ust_tracer_version *v)
 510 {
 511         struct ustcomm_ust_msg lum;
 512         struct ustcomm_ust_reply lur;
 513         int ret;
 514
 515         if (!v)
 516                 return -EINVAL;
 517
 518         memset(&lum, 0, sizeof(lum));
 519         lum.handle = LTTNG_UST_ROOT_HANDLE;
 520         lum.cmd = LTTNG_UST_TRACER_VERSION;
 521         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 522         if (ret)
 523                 return ret;
 524         memcpy(v, &lur.u.version, sizeof(*v));
 525         DBG("received tracer version");
 526         return 0;
 527 }
 528
 529 int ustctl_wait_quiescent(int sock)
 530 {
 531         struct ustcomm_ust_msg lum;
 532         struct ustcomm_ust_reply lur;
 533         int ret;
 534
 535         memset(&lum, 0, sizeof(lum));
 536         lum.handle = LTTNG_UST_ROOT_HANDLE;
 537         lum.cmd = LTTNG_UST_WAIT_QUIESCENT;
 538         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 539         if (ret)
 540                 return ret;
 541         DBG("waited for quiescent state");
 542         return 0;
 543 }
 544
 545 int ustctl_calibrate(int sock, struct lttng_ust_calibrate *calibrate)
 546 {
 547         if (!calibrate)
 548                 return -EINVAL;
 549
 550         return -ENOSYS;
 551 }
 552
 553 int ustctl_sock_flush_buffer(int sock, struct lttng_ust_object_data *object)
 554 {
 555         struct ustcomm_ust_msg lum;
 556         struct ustcomm_ust_reply lur;
 557         int ret;
 558
 559         if (!object)
 560                 return -EINVAL;
 561
 562         memset(&lum, 0, sizeof(lum));
 563         lum.handle = object->handle;
 564         lum.cmd = LTTNG_UST_FLUSH_BUFFER;
 565         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 566         if (ret)
 567                 return ret;
 568         DBG("flushed buffer handle %u", object->handle);
 569         return 0;
 570 }
 571
 572 static
 573 int ustctl_send_channel(int sock,
 574                 enum lttng_ust_chan_type type,
 575                 void *data,
 576                 uint64_t size,
 577                 int wakeup_fd,
 578                 int send_fd_only)
 579 {
 580         ssize_t len;
 581
 582         if (!send_fd_only) {
 583                 /* Send mmap size */
 584                 len = ustcomm_send_unix_sock(sock, &size, sizeof(size));
 585                 if (len != sizeof(size)) {
 586                         if (len < 0)
 587                                 return len;
 588                         else
 589                                 return -EIO;
 590                 }
 591
 592                 /* Send channel type */
 593                 len = ustcomm_send_unix_sock(sock, &type, sizeof(type));
 594                 if (len != sizeof(type)) {
 595                         if (len < 0)
 596                                 return len;
 597                         else
 598                                 return -EIO;
 599                 }
 600         }
 601
 602         /* Send channel data */
 603         len = ustcomm_send_unix_sock(sock, data, size);
 604         if (len != size) {
 605                 if (len < 0)
 606                         return len;
 607                 else
 608                         return -EIO;
 609         }
 610
 611         /* Send wakeup fd */
 612         len = ustcomm_send_fds_unix_sock(sock, &wakeup_fd, 1);
 613         if (len <= 0) {
 614                 if (len < 0)
 615                         return len;
 616                 else
 617                         return -EIO;
 618         }
 619         return 0;
 620 }
 621
 622 static
 623 int ustctl_send_stream(int sock,
 624                 uint32_t stream_nr,
 625                 uint64_t memory_map_size,
 626                 int shm_fd, int wakeup_fd,
 627                 int send_fd_only)
 628 {
 629         ssize_t len;
 630         int fds[2];
 631
 632         if (!send_fd_only) {
 633                 if (shm_fd < 0) {
 634                         /* finish iteration */
 635                         uint64_t v = -1;
 636
 637                         len = ustcomm_send_unix_sock(sock, &v, sizeof(v));
 638                         if (len != sizeof(v)) {
 639                                 if (len < 0)
 640                                         return len;
 641                                 else
 642                                         return -EIO;
 643                         }
 644                         return 0;
 645                 }
 646
 647                 /* Send mmap size */
 648                 len = ustcomm_send_unix_sock(sock, &memory_map_size,
 649                         sizeof(memory_map_size));
 650                 if (len != sizeof(memory_map_size)) {
 651                         if (len < 0)
 652                                 return len;
 653                         else
 654                                 return -EIO;
 655                 }
 656
 657                 /* Send stream nr */
 658                 len = ustcomm_send_unix_sock(sock, &stream_nr,
 659                         sizeof(stream_nr));
 660                 if (len != sizeof(stream_nr)) {
 661                         if (len < 0)
 662                                 return len;
 663                         else
 664                                 return -EIO;
 665                 }
 666         }
 667
 668         /* Send shm fd and wakeup fd */
 669         fds[0] = shm_fd;
 670         fds[1] = wakeup_fd;
 671         len = ustcomm_send_fds_unix_sock(sock, fds, 2);
 672         if (len <= 0) {
 673                 if (len < 0)
 674                         return len;
 675                 else
 676                         return -EIO;
 677         }
 678         return 0;
 679 }
 680
 681 int ustctl_recv_channel_from_consumer(int sock,
 682                 struct lttng_ust_object_data **_channel_data)
 683 {
 684         struct lttng_ust_object_data *channel_data;
 685         ssize_t len;
 686         int wakeup_fd;
 687         int ret;
 688
 689         channel_data = zmalloc(sizeof(*channel_data));
 690         if (!channel_data) {
 691                 ret = -ENOMEM;
 692                 goto error_alloc;
 693         }
 694         channel_data->type = LTTNG_UST_OBJECT_TYPE_CHANNEL;
 695         channel_data->handle = -1;
 696
 697         /* recv mmap size */
 698         len = ustcomm_recv_unix_sock(sock, &channel_data->size,
 699                         sizeof(channel_data->size));
 700         if (len != sizeof(channel_data->size)) {
 701                 if (len < 0)
 702                         ret = len;
 703                 else
 704                         ret = -EINVAL;
 705                 goto error;
 706         }
 707
 708         /* recv channel type */
 709         len = ustcomm_recv_unix_sock(sock, &channel_data->u.channel.type,
 710                         sizeof(channel_data->u.channel.type));
 711         if (len != sizeof(channel_data->u.channel.type)) {
 712                 if (len < 0)
 713                         ret = len;
 714                 else
 715                         ret = -EINVAL;
 716                 goto error;
 717         }
 718
 719         /* recv channel data */
 720         channel_data->u.channel.data = zmalloc(channel_data->size);
 721         if (!channel_data->u.channel.data) {
 722                 ret = -ENOMEM;
 723                 goto error;
 724         }
 725         len = ustcomm_recv_unix_sock(sock, channel_data->u.channel.data,
 726                         channel_data->size);
 727         if (len != channel_data->size) {
 728                 if (len < 0)
 729                         ret = len;
 730                 else
 731                         ret = -EINVAL;
 732                 goto error_recv_data;
 733         }
 734         /* recv wakeup fd */
 735         len = ustcomm_recv_fds_unix_sock(sock, &wakeup_fd, 1);
 736         if (len <= 0) {
 737                 if (len < 0) {
 738                         ret = len;
 739                         goto error_recv_data;
 740                 } else {
 741                         ret = -EIO;
 742                         goto error_recv_data;
 743                 }
 744         }
 745         channel_data->u.channel.wakeup_fd = wakeup_fd;
 746         *_channel_data = channel_data;
 747         return 0;
 748
 749 error_recv_data:
 750         free(channel_data->u.channel.data);
 751 error:
 752         free(channel_data);
 753 error_alloc:
 754         return ret;
 755 }
 756
 757 int ustctl_recv_stream_from_consumer(int sock,
 758                 struct lttng_ust_object_data **_stream_data)
 759 {
 760         struct lttng_ust_object_data *stream_data;
 761         ssize_t len;
 762         int ret;
 763         int fds[2];
 764
 765         stream_data = zmalloc(sizeof(*stream_data));
 766         if (!stream_data) {
 767                 ret = -ENOMEM;
 768                 goto error_alloc;
 769         }
 770
 771         stream_data->type = LTTNG_UST_OBJECT_TYPE_STREAM;
 772         stream_data->handle = -1;
 773
 774         /* recv mmap size */
 775         len = ustcomm_recv_unix_sock(sock, &stream_data->size,
 776                         sizeof(stream_data->size));
 777         if (len != sizeof(stream_data->size)) {
 778                 if (len < 0)
 779                         ret = len;
 780                 else
 781                         ret = -EINVAL;
 782                 goto error;
 783         }
 784         if (stream_data->size == -1) {
 785                 ret = -LTTNG_UST_ERR_NOENT;
 786                 goto error;
 787         }
 788
 789         /* recv stream nr */
 790         len = ustcomm_recv_unix_sock(sock, &stream_data->u.stream.stream_nr,
 791                         sizeof(stream_data->u.stream.stream_nr));
 792         if (len != sizeof(stream_data->u.stream.stream_nr)) {
 793                 if (len < 0)
 794                         ret = len;
 795                 else
 796                         ret = -EINVAL;
 797                 goto error;
 798         }
 799
 800         /* recv shm fd and wakeup fd */
 801         len = ustcomm_recv_fds_unix_sock(sock, fds, 2);
 802         if (len <= 0) {
 803                 if (len < 0) {
 804                         ret = len;
 805                         goto error;
 806                 } else {
 807                         ret = -EIO;
 808                         goto error;
 809                 }
 810         }
 811         stream_data->u.stream.shm_fd = fds[0];
 812         stream_data->u.stream.wakeup_fd = fds[1];
 813         *_stream_data = stream_data;
 814         return 0;
 815
 816 error:
 817         free(stream_data);
 818 error_alloc:
 819         return ret;
 820 }
 821
 822 int ustctl_send_channel_to_ust(int sock, int session_handle,
 823                 struct lttng_ust_object_data *channel_data)
 824 {
 825         struct ustcomm_ust_msg lum;
 826         struct ustcomm_ust_reply lur;
 827         int ret;
 828
 829         if (!channel_data)
 830                 return -EINVAL;
 831
 832         memset(&lum, 0, sizeof(lum));
 833         lum.handle = session_handle;
 834         lum.cmd = LTTNG_UST_CHANNEL;
 835         lum.u.channel.len = channel_data->size;
 836         lum.u.channel.type = channel_data->u.channel.type;
 837         ret = ustcomm_send_app_msg(sock, &lum);
 838         if (ret)
 839                 return ret;
 840
 841         ret = ustctl_send_channel(sock,
 842                         channel_data->u.channel.type,
 843                         channel_data->u.channel.data,
 844                         channel_data->size,
 845                         channel_data->u.channel.wakeup_fd,
 846                         1);
 847         if (ret)
 848                 return ret;
 849         ret = ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 850         if (!ret) {
 851                 channel_data->handle = lur.ret_val;
 852         }
 853         return ret;
 854 }
 855
 856 int ustctl_send_stream_to_ust(int sock,
 857                 struct lttng_ust_object_data *channel_data,
 858                 struct lttng_ust_object_data *stream_data)
 859 {
 860         struct ustcomm_ust_msg lum;
 861         struct ustcomm_ust_reply lur;
 862         int ret;
 863
 864         memset(&lum, 0, sizeof(lum));
 865         lum.handle = channel_data->handle;
 866         lum.cmd = LTTNG_UST_STREAM;
 867         lum.u.stream.len = stream_data->size;
 868         lum.u.stream.stream_nr = stream_data->u.stream.stream_nr;
 869         ret = ustcomm_send_app_msg(sock, &lum);
 870         if (ret)
 871                 return ret;
 872
 873         assert(stream_data);
 874         assert(stream_data->type == LTTNG_UST_OBJECT_TYPE_STREAM);
 875
 876         ret = ustctl_send_stream(sock,
 877                         stream_data->u.stream.stream_nr,
 878                         stream_data->size,
 879                         stream_data->u.stream.shm_fd,
 880                         stream_data->u.stream.wakeup_fd, 1);
 881         if (ret)
 882                 return ret;
 883         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 884 }
 885
 886 int ustctl_duplicate_ust_object_data(struct lttng_ust_object_data **dest,
 887                 struct lttng_ust_object_data *src)
 888 {
 889         struct lttng_ust_object_data *obj;
 890         int ret;
 891
 892         if (src->handle != -1) {
 893                 ret = -EINVAL;
 894                 goto error;
 895         }
 896
 897         obj = zmalloc(sizeof(*obj));
 898         if (!obj) {
 899                 ret = -ENOMEM;
 900                 goto error;
 901         }
 902
 903         obj->type = src->type;
 904         obj->handle = src->handle;
 905         obj->size = src->size;
 906
 907         switch (obj->type) {
 908         case LTTNG_UST_OBJECT_TYPE_CHANNEL:
 909         {
 910                 obj->u.channel.type = src->u.channel.type;
 911                 if (src->u.channel.wakeup_fd >= 0) {
 912                         obj->u.channel.wakeup_fd =
 913                                 dup(src->u.channel.wakeup_fd);
 914                         if (obj->u.channel.wakeup_fd < 0) {
 915                                 ret = errno;
 916                                 goto chan_error_wakeup_fd;
 917                         }
 918                 } else {
 919                         obj->u.channel.wakeup_fd =
 920                                 src->u.channel.wakeup_fd;
 921                 }
 922                 obj->u.channel.data = zmalloc(obj->size);
 923                 if (!obj->u.channel.data) {
 924                         ret = -ENOMEM;
 925                         goto chan_error_alloc;
 926                 }
 927                 memcpy(obj->u.channel.data, src->u.channel.data, obj->size);
 928                 break;
 929
 930         chan_error_alloc:
 931                 if (src->u.channel.wakeup_fd >= 0) {
 932                         int closeret;
 933
 934                         closeret = close(obj->u.channel.wakeup_fd);
 935                         if (closeret) {
 936                                 PERROR("close");
 937                         }
 938                 }
 939         chan_error_wakeup_fd:
 940                 goto error_type;
 941
 942         }
 943
 944         case LTTNG_UST_OBJECT_TYPE_STREAM:
 945         {
 946                 obj->u.stream.stream_nr = src->u.stream.stream_nr;
 947                 if (src->u.stream.wakeup_fd >= 0) {
 948                         obj->u.stream.wakeup_fd =
 949                                 dup(src->u.stream.wakeup_fd);
 950                         if (obj->u.stream.wakeup_fd < 0) {
 951                                 ret = errno;
 952                                 goto stream_error_wakeup_fd;
 953                         }
 954                 } else {
 955                         obj->u.stream.wakeup_fd =
 956                                 src->u.stream.wakeup_fd;
 957                 }
 958
 959                 if (src->u.stream.shm_fd >= 0) {
 960                         obj->u.stream.shm_fd =
 961                                 dup(src->u.stream.shm_fd);
 962                         if (obj->u.stream.shm_fd < 0) {
 963                                 ret = errno;
 964                                 goto stream_error_shm_fd;
 965                         }
 966                 } else {
 967                         obj->u.stream.shm_fd =
 968                                 src->u.stream.shm_fd;
 969                 }
 970                 break;
 971
 972         stream_error_shm_fd:
 973                 if (src->u.stream.wakeup_fd >= 0) {
 974                         int closeret;
 975
 976                         closeret = close(obj->u.stream.wakeup_fd);
 977                         if (closeret) {
 978                                 PERROR("close");
 979                         }
 980                 }
 981         stream_error_wakeup_fd:
 982                 goto error_type;
 983         }
 984
 985         default:
 986                 ret = -EINVAL;
 987                 goto error_type;
 988         }
 989
 990         *dest = obj;
 991         return 0;
 992
 993 error_type:
 994         free(obj);
 995 error:
 996         return ret;
 997 }
 998
 999
1000 /* Buffer operations */
1001
1002 int ustctl_get_nr_stream_per_channel(void)
1003 {
1004         return num_possible_cpus();
1005 }
1006
1007 struct ustctl_consumer_channel *
1008         ustctl_create_channel(struct ustctl_consumer_channel_attr *attr,
1009                 const int *stream_fds, int nr_stream_fds)
1010 {
1011         struct ustctl_consumer_channel *chan;
1012         const char *transport_name;
1013         struct lttng_transport *transport;
1014
1015         switch (attr->type) {
1016         case LTTNG_UST_CHAN_PER_CPU:
1017                 if (attr->output == LTTNG_UST_MMAP) {
1018                         if (attr->overwrite) {
1019                                 if (attr->read_timer_interval == 0) {
1020                                         transport_name = "relay-overwrite-mmap";
1021                                 } else {
1022                                         transport_name = "relay-overwrite-rt-mmap";
1023                                 }
1024                         } else {
1025                                 if (attr->read_timer_interval == 0) {
1026                                         transport_name = "relay-discard-mmap";
1027                                 } else {
1028                                         transport_name = "relay-discard-rt-mmap";
1029                                 }
1030                         }
1031                 } else {
1032                         return NULL;
1033                 }
1034                 break;
1035         case LTTNG_UST_CHAN_METADATA:
1036                 if (attr->output == LTTNG_UST_MMAP)
1037                         transport_name = "relay-metadata-mmap";
1038                 else
1039                         return NULL;
1040                 break;
1041         default:
1042                 transport_name = "<unknown>";
1043                 return NULL;
1044         }
1045
1046         transport = lttng_transport_find(transport_name);
1047         if (!transport) {
1048                 DBG("LTTng transport %s not found\n",
1049                         transport_name);
1050                 return NULL;
1051         }
1052
1053         chan = zmalloc(sizeof(*chan));
1054         if (!chan)
1055                 return NULL;
1056
1057         chan->chan = transport->ops.channel_create(transport_name, NULL,
1058                         attr->subbuf_size, attr->num_subbuf,
1059                         attr->switch_timer_interval,
1060                         attr->read_timer_interval,
1061                         attr->uuid, attr->chan_id,
1062                         stream_fds, nr_stream_fds,
1063                         attr->blocking_timeout);
1064         if (!chan->chan) {
1065                 goto chan_error;
1066         }
1067         chan->chan->ops = &transport->ops;
1068         memcpy(&chan->attr, attr, sizeof(chan->attr));
1069         chan->wait_fd = ustctl_channel_get_wait_fd(chan);
1070         chan->wakeup_fd = ustctl_channel_get_wakeup_fd(chan);
1071         return chan;
1072
1073 chan_error:
1074         free(chan);
1075         return NULL;
1076 }
1077
1078 void ustctl_destroy_channel(struct ustctl_consumer_channel *chan)
1079 {
1080         (void) ustctl_channel_close_wait_fd(chan);
1081         (void) ustctl_channel_close_wakeup_fd(chan);
1082         chan->chan->ops->channel_destroy(chan->chan);
1083         free(chan);
1084 }
1085
1086 int ustctl_send_channel_to_sessiond(int sock,
1087                 struct ustctl_consumer_channel *channel)
1088 {
1089         struct shm_object_table *table;
1090
1091         table = channel->chan->handle->table;
1092         if (table->size <= 0)
1093                 return -EINVAL;
1094         return ustctl_send_channel(sock,
1095                         channel->attr.type,
1096                         table->objects[0].memory_map,
1097                         table->objects[0].memory_map_size,
1098                         channel->wakeup_fd,
1099                         0);
1100 }
1101
1102 int ustctl_send_stream_to_sessiond(int sock,
1103                 struct ustctl_consumer_stream *stream)
1104 {
1105         if (!stream)
1106                 return ustctl_send_stream(sock, -1U, -1U, -1, -1, 0);
1107
1108         return ustctl_send_stream(sock,
1109                         stream->cpu,
1110                         stream->memory_map_size,
1111                         stream->shm_fd, stream->wakeup_fd,
1112                         0);
1113 }
1114
1115 int ustctl_write_metadata_to_channel(
1116                 struct ustctl_consumer_channel *channel,
1117                 const char *metadata_str,       /* NOT null-terminated */
1118                 size_t len)                     /* metadata length */
1119 {
1120         struct lttng_ust_lib_ring_buffer_ctx ctx;
1121         struct lttng_channel *chan = channel->chan;
1122         const char *str = metadata_str;
1123         int ret = 0, waitret;
1124         size_t reserve_len, pos;
1125
1126         for (pos = 0; pos < len; pos += reserve_len) {
1127                 reserve_len = min_t(size_t,
1128                                 chan->ops->packet_avail_size(chan->chan, chan->handle),
1129                                 len - pos);
1130                 lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
1131                                          sizeof(char), -1, chan->handle, NULL);
1132                 /*
1133                  * We don't care about metadata buffer's records lost
1134                  * count, because we always retry here. Report error if
1135                  * we need to bail out after timeout or being
1136                  * interrupted.
1137                  */
1138                 waitret = wait_cond_interruptible_timeout(
1139                         ({
1140                                 ret = chan->ops->event_reserve(&ctx, 0);
1141                                 ret != -ENOBUFS || !ret;
1142                         }),
1143                         LTTNG_METADATA_TIMEOUT_MSEC);
1144                 if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) {
1145                         DBG("LTTng: Failure to write metadata to buffers (%s)\n",
1146                                 waitret == -EINTR ? "interrupted" :
1147                                         (ret == -ENOBUFS ? "timeout" : "I/O error"));
1148                         if (waitret == -EINTR)
1149                                 ret = waitret;
1150                         goto end;
1151                 }
1152                 chan->ops->event_write(&ctx, &str[pos], reserve_len);
1153                 chan->ops->event_commit(&ctx);
1154         }
1155 end:
1156         return ret;
1157 }
1158
1159 /*
1160  * Write at most one packet in the channel.
1161  * Returns the number of bytes written on success, < 0 on error.
1162  */
1163 ssize_t ustctl_write_one_packet_to_channel(
1164                 struct ustctl_consumer_channel *channel,
1165                 const char *metadata_str,       /* NOT null-terminated */
1166                 size_t len)                     /* metadata length */
1167 {
1168         struct lttng_ust_lib_ring_buffer_ctx ctx;
1169         struct lttng_channel *chan = channel->chan;
1170         const char *str = metadata_str;
1171         ssize_t reserve_len;
1172         int ret;
1173
1174         reserve_len = min_t(ssize_t,
1175                         chan->ops->packet_avail_size(chan->chan, chan->handle),
1176                         len);
1177         lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
1178                         sizeof(char), -1, chan->handle, NULL);
1179         ret = chan->ops->event_reserve(&ctx, 0);
1180         if (ret != 0) {
1181                 DBG("LTTng: event reservation failed");
1182                 assert(ret < 0);
1183                 reserve_len = ret;
1184                 goto end;
1185         }
1186         chan->ops->event_write(&ctx, str, reserve_len);
1187         chan->ops->event_commit(&ctx);
1188
1189 end:
1190         return reserve_len;
1191 }
1192
1193 int ustctl_channel_close_wait_fd(struct ustctl_consumer_channel *consumer_chan)
1194 {
1195         struct channel *chan;
1196         int ret;
1197
1198         chan = consumer_chan->chan->chan;
1199         ret = ring_buffer_channel_close_wait_fd(&chan->backend.config,
1200                         chan, chan->handle);
1201         if (!ret)
1202                 consumer_chan->wait_fd = -1;
1203         return ret;
1204 }
1205
1206 int ustctl_channel_close_wakeup_fd(struct ustctl_consumer_channel *consumer_chan)
1207 {
1208         struct channel *chan;
1209         int ret;
1210
1211         chan = consumer_chan->chan->chan;
1212         ret = ring_buffer_channel_close_wakeup_fd(&chan->backend.config,
1213                         chan, chan->handle);
1214         if (!ret)
1215                 consumer_chan->wakeup_fd = -1;
1216         return ret;
1217 }
1218
1219 int ustctl_stream_close_wait_fd(struct ustctl_consumer_stream *stream)
1220 {
1221         struct channel *chan;
1222
1223         chan = stream->chan->chan->chan;
1224         return ring_buffer_stream_close_wait_fd(&chan->backend.config,
1225                         chan, stream->handle, stream->cpu);
1226 }
1227
1228 int ustctl_stream_close_wakeup_fd(struct ustctl_consumer_stream *stream)
1229 {
1230         struct channel *chan;
1231
1232         chan = stream->chan->chan->chan;
1233         return ring_buffer_stream_close_wakeup_fd(&chan->backend.config,
1234                         chan, stream->handle, stream->cpu);
1235 }
1236
1237 struct ustctl_consumer_stream *
1238         ustctl_create_stream(struct ustctl_consumer_channel *channel,
1239                         int cpu)
1240 {
1241         struct ustctl_consumer_stream *stream;
1242         struct lttng_ust_shm_handle *handle;
1243         struct channel *chan;
1244         int shm_fd, wait_fd, wakeup_fd;
1245         uint64_t memory_map_size;
1246         struct lttng_ust_lib_ring_buffer *buf;
1247         int ret;
1248
1249         if (!channel)
1250                 return NULL;
1251         handle = channel->chan->handle;
1252         if (!handle)
1253                 return NULL;
1254
1255         chan = channel->chan->chan;
1256         buf = channel_get_ring_buffer(&chan->backend.config,
1257                 chan, cpu, handle, &shm_fd, &wait_fd,
1258                 &wakeup_fd, &memory_map_size);
1259         if (!buf)
1260                 return NULL;
1261         ret = lib_ring_buffer_open_read(buf, handle);
1262         if (ret)
1263                 return NULL;
1264
1265         stream = zmalloc(sizeof(*stream));
1266         if (!stream)
1267                 goto alloc_error;
1268         stream->handle = handle;
1269         stream->buf = buf;
1270         stream->chan = channel;
1271         stream->shm_fd = shm_fd;
1272         stream->wait_fd = wait_fd;
1273         stream->wakeup_fd = wakeup_fd;
1274         stream->memory_map_size = memory_map_size;
1275         stream->cpu = cpu;
1276         return stream;
1277
1278 alloc_error:
1279         return NULL;
1280 }
1281
1282 void ustctl_destroy_stream(struct ustctl_consumer_stream *stream)
1283 {
1284         struct lttng_ust_lib_ring_buffer *buf;
1285         struct ustctl_consumer_channel *consumer_chan;
1286
1287         assert(stream);
1288         buf = stream->buf;
1289         consumer_chan = stream->chan;
1290         (void) ustctl_stream_close_wait_fd(stream);
1291         (void) ustctl_stream_close_wakeup_fd(stream);
1292         lib_ring_buffer_release_read(buf, consumer_chan->chan->handle);
1293         free(stream);
1294 }
1295
1296 int ustctl_channel_get_wait_fd(struct ustctl_consumer_channel *chan)
1297 {
1298         if (!chan)
1299                 return -EINVAL;
1300         return shm_get_wait_fd(chan->chan->handle,
1301                 &chan->chan->handle->chan._ref);
1302 }
1303
1304 int ustctl_channel_get_wakeup_fd(struct ustctl_consumer_channel *chan)
1305 {
1306         if (!chan)
1307                 return -EINVAL;
1308         return shm_get_wakeup_fd(chan->chan->handle,
1309                 &chan->chan->handle->chan._ref);
1310 }
1311
1312 int ustctl_stream_get_wait_fd(struct ustctl_consumer_stream *stream)
1313 {
1314         struct lttng_ust_lib_ring_buffer *buf;
1315         struct ustctl_consumer_channel *consumer_chan;
1316
1317         if (!stream)
1318                 return -EINVAL;
1319         buf = stream->buf;
1320         consumer_chan = stream->chan;
1321         return shm_get_wait_fd(consumer_chan->chan->handle, &buf->self._ref);
1322 }
1323
1324 int ustctl_stream_get_wakeup_fd(struct ustctl_consumer_stream *stream)
1325 {
1326         struct lttng_ust_lib_ring_buffer *buf;
1327         struct ustctl_consumer_channel *consumer_chan;
1328
1329         if (!stream)
1330                 return -EINVAL;
1331         buf = stream->buf;
1332         consumer_chan = stream->chan;
1333         return shm_get_wakeup_fd(consumer_chan->chan->handle, &buf->self._ref);
1334 }
1335
1336 /* For mmap mode, readable without "get" operation */
1337
1338 void *ustctl_get_mmap_base(struct ustctl_consumer_stream *stream)
1339 {
1340         struct lttng_ust_lib_ring_buffer *buf;
1341         struct ustctl_consumer_channel *consumer_chan;
1342
1343         if (!stream)
1344                 return NULL;
1345         buf = stream->buf;
1346         consumer_chan = stream->chan;
1347         return shmp(consumer_chan->chan->handle, buf->backend.memory_map);
1348 }
1349
1350 /* returns the length to mmap. */
1351 int ustctl_get_mmap_len(struct ustctl_consumer_stream *stream,
1352                 unsigned long *len)
1353 {
1354         struct ustctl_consumer_channel *consumer_chan;
1355         unsigned long mmap_buf_len;
1356         struct channel *chan;
1357
1358         if (!stream)
1359                 return -EINVAL;
1360         consumer_chan = stream->chan;
1361         chan = consumer_chan->chan->chan;
1362         if (chan->backend.config.output != RING_BUFFER_MMAP)
1363                 return -EINVAL;
1364         mmap_buf_len = chan->backend.buf_size;
1365         if (chan->backend.extra_reader_sb)
1366                 mmap_buf_len += chan->backend.subbuf_size;
1367         if (mmap_buf_len > INT_MAX)
1368                 return -EFBIG;
1369         *len = mmap_buf_len;
1370         return 0;
1371 }
1372
1373 /* returns the maximum size for sub-buffers. */
1374 int ustctl_get_max_subbuf_size(struct ustctl_consumer_stream *stream,
1375                 unsigned long *len)
1376 {
1377         struct ustctl_consumer_channel *consumer_chan;
1378         struct channel *chan;
1379
1380         if (!stream)
1381                 return -EINVAL;
1382         consumer_chan = stream->chan;
1383         chan = consumer_chan->chan->chan;
1384         *len = chan->backend.subbuf_size;
1385         return 0;
1386 }
1387
1388 /*
1389  * For mmap mode, operate on the current packet (between get/put or
1390  * get_next/put_next).
1391  */
1392
1393 /* returns the offset of the subbuffer belonging to the mmap reader. */
1394 int ustctl_get_mmap_read_offset(struct ustctl_consumer_stream *stream,
1395                 unsigned long *off)
1396 {
1397         struct channel *chan;
1398         unsigned long sb_bindex;
1399         struct lttng_ust_lib_ring_buffer *buf;
1400         struct ustctl_consumer_channel *consumer_chan;
1401         struct lttng_ust_lib_ring_buffer_backend_pages_shmp *barray_idx;
1402         struct lttng_ust_lib_ring_buffer_backend_pages *pages;
1403
1404         if (!stream)
1405                 return -EINVAL;
1406         buf = stream->buf;
1407         consumer_chan = stream->chan;
1408         chan = consumer_chan->chan->chan;
1409         if (chan->backend.config.output != RING_BUFFER_MMAP)
1410                 return -EINVAL;
1411         sb_bindex = subbuffer_id_get_index(&chan->backend.config,
1412                                         buf->backend.buf_rsb.id);
1413         barray_idx = shmp_index(consumer_chan->chan->handle, buf->backend.array,
1414                         sb_bindex);
1415         if (!barray_idx)
1416                 return -EINVAL;
1417         pages = shmp(consumer_chan->chan->handle, barray_idx->shmp);
1418         if (!pages)
1419                 return -EINVAL;
1420         *off = pages->mmap_offset;
1421         return 0;
1422 }
1423
1424 /* returns the size of the current sub-buffer, without padding (for mmap). */
1425 int ustctl_get_subbuf_size(struct ustctl_consumer_stream *stream,
1426                 unsigned long *len)
1427 {
1428         struct ustctl_consumer_channel *consumer_chan;
1429         struct channel *chan;
1430         struct lttng_ust_lib_ring_buffer *buf;
1431
1432         if (!stream)
1433                 return -EINVAL;
1434
1435         buf = stream->buf;
1436         consumer_chan = stream->chan;
1437         chan = consumer_chan->chan->chan;
1438         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
1439                 consumer_chan->chan->handle);
1440         return 0;
1441 }
1442
1443 /* returns the size of the current sub-buffer, without padding (for mmap). */
1444 int ustctl_get_padded_subbuf_size(struct ustctl_consumer_stream *stream,
1445                 unsigned long *len)
1446 {
1447         struct ustctl_consumer_channel *consumer_chan;
1448         struct channel *chan;
1449         struct lttng_ust_lib_ring_buffer *buf;
1450
1451         if (!stream)
1452                 return -EINVAL;
1453         buf = stream->buf;
1454         consumer_chan = stream->chan;
1455         chan = consumer_chan->chan->chan;
1456         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
1457                 consumer_chan->chan->handle);
1458         *len = PAGE_ALIGN(*len);
1459         return 0;
1460 }
1461
1462 /* Get exclusive read access to the next sub-buffer that can be read. */
1463 int ustctl_get_next_subbuf(struct ustctl_consumer_stream *stream)
1464 {
1465         struct lttng_ust_lib_ring_buffer *buf;
1466         struct ustctl_consumer_channel *consumer_chan;
1467
1468         if (!stream)
1469                 return -EINVAL;
1470         buf = stream->buf;
1471         consumer_chan = stream->chan;
1472         return lib_ring_buffer_get_next_subbuf(buf,
1473                         consumer_chan->chan->handle);
1474 }
1475
1476
1477 /* Release exclusive sub-buffer access, move consumer forward. */
1478 int ustctl_put_next_subbuf(struct ustctl_consumer_stream *stream)
1479 {
1480         struct lttng_ust_lib_ring_buffer *buf;
1481         struct ustctl_consumer_channel *consumer_chan;
1482
1483         if (!stream)
1484                 return -EINVAL;
1485         buf = stream->buf;
1486         consumer_chan = stream->chan;
1487         lib_ring_buffer_put_next_subbuf(buf, consumer_chan->chan->handle);
1488         return 0;
1489 }
1490
1491 /* snapshot */
1492
1493 /* Get a snapshot of the current ring buffer producer and consumer positions */
1494 int ustctl_snapshot(struct ustctl_consumer_stream *stream)
1495 {
1496         struct lttng_ust_lib_ring_buffer *buf;
1497         struct ustctl_consumer_channel *consumer_chan;
1498
1499         if (!stream)
1500                 return -EINVAL;
1501         buf = stream->buf;
1502         consumer_chan = stream->chan;
1503         return lib_ring_buffer_snapshot(buf, &buf->cons_snapshot,
1504                         &buf->prod_snapshot, consumer_chan->chan->handle);
1505 }
1506
1507 /*
1508  * Get a snapshot of the current ring buffer producer and consumer positions
1509  * even if the consumed and produced positions are contained within the same
1510  * subbuffer.
1511  */
1512 int ustctl_snapshot_sample_positions(struct ustctl_consumer_stream *stream)
1513 {
1514         struct lttng_ust_lib_ring_buffer *buf;
1515         struct ustctl_consumer_channel *consumer_chan;
1516
1517         if (!stream)
1518                 return -EINVAL;
1519         buf = stream->buf;
1520         consumer_chan = stream->chan;
1521         return lib_ring_buffer_snapshot_sample_positions(buf,
1522                         &buf->cons_snapshot, &buf->prod_snapshot,
1523                         consumer_chan->chan->handle);
1524 }
1525
1526 /* Get the consumer position (iteration start) */
1527 int ustctl_snapshot_get_consumed(struct ustctl_consumer_stream *stream,
1528                 unsigned long *pos)
1529 {
1530         struct lttng_ust_lib_ring_buffer *buf;
1531
1532         if (!stream)
1533                 return -EINVAL;
1534         buf = stream->buf;
1535         *pos = buf->cons_snapshot;
1536         return 0;
1537 }
1538
1539 /* Get the producer position (iteration end) */
1540 int ustctl_snapshot_get_produced(struct ustctl_consumer_stream *stream,
1541                 unsigned long *pos)
1542 {
1543         struct lttng_ust_lib_ring_buffer *buf;
1544
1545         if (!stream)
1546                 return -EINVAL;
1547         buf = stream->buf;
1548         *pos = buf->prod_snapshot;
1549         return 0;
1550 }
1551
1552 /* Get exclusive read access to the specified sub-buffer position */
1553 int ustctl_get_subbuf(struct ustctl_consumer_stream *stream,
1554                 unsigned long *pos)
1555 {
1556         struct lttng_ust_lib_ring_buffer *buf;
1557         struct ustctl_consumer_channel *consumer_chan;
1558
1559         if (!stream)
1560                 return -EINVAL;
1561         buf = stream->buf;
1562         consumer_chan = stream->chan;
1563         return lib_ring_buffer_get_subbuf(buf, *pos,
1564                         consumer_chan->chan->handle);
1565 }
1566
1567 /* Release exclusive sub-buffer access */
1568 int ustctl_put_subbuf(struct ustctl_consumer_stream *stream)
1569 {
1570         struct lttng_ust_lib_ring_buffer *buf;
1571         struct ustctl_consumer_channel *consumer_chan;
1572
1573         if (!stream)
1574                 return -EINVAL;
1575         buf = stream->buf;
1576         consumer_chan = stream->chan;
1577         lib_ring_buffer_put_subbuf(buf, consumer_chan->chan->handle);
1578         return 0;
1579 }
1580
1581 void ustctl_flush_buffer(struct ustctl_consumer_stream *stream,
1582                 int producer_active)
1583 {
1584         struct lttng_ust_lib_ring_buffer *buf;
1585         struct ustctl_consumer_channel *consumer_chan;
1586
1587         assert(stream);
1588         buf = stream->buf;
1589         consumer_chan = stream->chan;
1590         lib_ring_buffer_switch_slow(buf,
1591                 producer_active ? SWITCH_ACTIVE : SWITCH_FLUSH,
1592                 consumer_chan->chan->handle);
1593 }
1594
1595 void ustctl_clear_buffer(struct ustctl_consumer_stream *stream)
1596 {
1597         struct lttng_ust_lib_ring_buffer *buf;
1598         struct ustctl_consumer_channel *consumer_chan;
1599
1600         assert(stream);
1601         buf = stream->buf;
1602         consumer_chan = stream->chan;
1603         lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE,
1604                 consumer_chan->chan->handle);
1605         lib_ring_buffer_clear_reader(buf, consumer_chan->chan->handle);
1606 }
1607
1608 static
1609 struct lttng_ust_client_lib_ring_buffer_client_cb *get_client_cb(
1610                 struct lttng_ust_lib_ring_buffer *buf,
1611                 struct lttng_ust_shm_handle *handle)
1612 {
1613         struct channel *chan;
1614         const struct lttng_ust_lib_ring_buffer_config *config;
1615         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1616
1617         chan = shmp(handle, buf->backend.chan);
1618         if (!chan)
1619                 return NULL;
1620         config = &chan->backend.config;
1621         if (!config->cb_ptr)
1622                 return NULL;
1623         client_cb = caa_container_of(config->cb_ptr,
1624                         struct lttng_ust_client_lib_ring_buffer_client_cb,
1625                         parent);
1626         return client_cb;
1627 }
1628
1629 int ustctl_get_timestamp_begin(struct ustctl_consumer_stream *stream,
1630                 uint64_t *timestamp_begin)
1631 {
1632         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1633         struct lttng_ust_lib_ring_buffer *buf;
1634         struct lttng_ust_shm_handle *handle;
1635
1636         if (!stream || !timestamp_begin)
1637                 return -EINVAL;
1638         buf = stream->buf;
1639         handle = stream->chan->chan->handle;
1640         client_cb = get_client_cb(buf, handle);
1641         if (!client_cb)
1642                 return -ENOSYS;
1643         return client_cb->timestamp_begin(buf, handle, timestamp_begin);
1644 }
1645
1646 int ustctl_get_timestamp_end(struct ustctl_consumer_stream *stream,
1647         uint64_t *timestamp_end)
1648 {
1649         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1650         struct lttng_ust_lib_ring_buffer *buf;
1651         struct lttng_ust_shm_handle *handle;
1652
1653         if (!stream || !timestamp_end)
1654                 return -EINVAL;
1655         buf = stream->buf;
1656         handle = stream->chan->chan->handle;
1657         client_cb = get_client_cb(buf, handle);
1658         if (!client_cb)
1659                 return -ENOSYS;
1660         return client_cb->timestamp_end(buf, handle, timestamp_end);
1661 }
1662
1663 int ustctl_get_events_discarded(struct ustctl_consumer_stream *stream,
1664         uint64_t *events_discarded)
1665 {
1666         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1667         struct lttng_ust_lib_ring_buffer *buf;
1668         struct lttng_ust_shm_handle *handle;
1669
1670         if (!stream || !events_discarded)
1671                 return -EINVAL;
1672         buf = stream->buf;
1673         handle = stream->chan->chan->handle;
1674         client_cb = get_client_cb(buf, handle);
1675         if (!client_cb)
1676                 return -ENOSYS;
1677         return client_cb->events_discarded(buf, handle, events_discarded);
1678 }
1679
1680 int ustctl_get_content_size(struct ustctl_consumer_stream *stream,
1681         uint64_t *content_size)
1682 {
1683         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1684         struct lttng_ust_lib_ring_buffer *buf;
1685         struct lttng_ust_shm_handle *handle;
1686
1687         if (!stream || !content_size)
1688                 return -EINVAL;
1689         buf = stream->buf;
1690         handle = stream->chan->chan->handle;
1691         client_cb = get_client_cb(buf, handle);
1692         if (!client_cb)
1693                 return -ENOSYS;
1694         return client_cb->content_size(buf, handle, content_size);
1695 }
1696
1697 int ustctl_get_packet_size(struct ustctl_consumer_stream *stream,
1698         uint64_t *packet_size)
1699 {
1700         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1701         struct lttng_ust_lib_ring_buffer *buf;
1702         struct lttng_ust_shm_handle *handle;
1703
1704         if (!stream || !packet_size)
1705                 return -EINVAL;
1706         buf = stream->buf;
1707         handle = stream->chan->chan->handle;
1708         client_cb = get_client_cb(buf, handle);
1709         if (!client_cb)
1710                 return -ENOSYS;
1711         return client_cb->packet_size(buf, handle, packet_size);
1712 }
1713
1714 int ustctl_get_stream_id(struct ustctl_consumer_stream *stream,
1715                 uint64_t *stream_id)
1716 {
1717         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1718         struct lttng_ust_lib_ring_buffer *buf;
1719         struct lttng_ust_shm_handle *handle;
1720
1721         if (!stream || !stream_id)
1722                 return -EINVAL;
1723         buf = stream->buf;
1724         handle = stream->chan->chan->handle;
1725         client_cb = get_client_cb(buf, handle);
1726         if (!client_cb)
1727                 return -ENOSYS;
1728         return client_cb->stream_id(buf, handle, stream_id);
1729 }
1730
1731 int ustctl_get_current_timestamp(struct ustctl_consumer_stream *stream,
1732                 uint64_t *ts)
1733 {
1734         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1735         struct lttng_ust_lib_ring_buffer *buf;
1736         struct lttng_ust_shm_handle *handle;
1737
1738         if (!stream || !ts)
1739                 return -EINVAL;
1740         buf = stream->buf;
1741         handle = stream->chan->chan->handle;
1742         client_cb = get_client_cb(buf, handle);
1743         if (!client_cb || !client_cb->current_timestamp)
1744                 return -ENOSYS;
1745         return client_cb->current_timestamp(buf, handle, ts);
1746 }
1747
1748 int ustctl_get_sequence_number(struct ustctl_consumer_stream *stream,
1749                 uint64_t *seq)
1750 {
1751         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1752         struct lttng_ust_lib_ring_buffer *buf;
1753         struct lttng_ust_shm_handle *handle;
1754
1755         if (!stream || !seq)
1756                 return -EINVAL;
1757         buf = stream->buf;
1758         handle = stream->chan->chan->handle;
1759         client_cb = get_client_cb(buf, handle);
1760         if (!client_cb || !client_cb->sequence_number)
1761                 return -ENOSYS;
1762         return client_cb->sequence_number(buf, handle, seq);
1763 }
1764
1765 int ustctl_get_instance_id(struct ustctl_consumer_stream *stream,
1766                 uint64_t *id)
1767 {
1768         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1769         struct lttng_ust_lib_ring_buffer *buf;
1770         struct lttng_ust_shm_handle *handle;
1771
1772         if (!stream || !id)
1773                 return -EINVAL;
1774         buf = stream->buf;
1775         handle = stream->chan->chan->handle;
1776         client_cb = get_client_cb(buf, handle);
1777         if (!client_cb)
1778                 return -ENOSYS;
1779         return client_cb->instance_id(buf, handle, id);
1780 }
1781
1782 #ifdef LTTNG_UST_HAVE_PERF_EVENT
1783
1784 int ustctl_has_perf_counters(void)
1785 {
1786         return 1;
1787 }
1788
1789 #else
1790
1791 int ustctl_has_perf_counters(void)
1792 {
1793         return 0;
1794 }
1795
1796 #endif
1797
1798 /*
1799  * Returns 0 on success, negative error value on error.
1800  */
1801 int ustctl_recv_reg_msg(int sock,
1802         enum ustctl_socket_type *type,
1803         uint32_t *major,
1804         uint32_t *minor,
1805         uint32_t *pid,
1806         uint32_t *ppid,
1807         uint32_t *uid,
1808         uint32_t *gid,
1809         uint32_t *bits_per_long,
1810         uint32_t *uint8_t_alignment,
1811         uint32_t *uint16_t_alignment,
1812         uint32_t *uint32_t_alignment,
1813         uint32_t *uint64_t_alignment,
1814         uint32_t *long_alignment,
1815         int *byte_order,
1816         char *name)
1817 {
1818         ssize_t len;
1819         struct ustctl_reg_msg reg_msg;
1820
1821         len = ustcomm_recv_unix_sock(sock, &reg_msg, sizeof(reg_msg));
1822         if (len > 0 && len != sizeof(reg_msg))
1823                 return -EIO;
1824         if (len == 0)
1825                 return -EPIPE;
1826         if (len < 0)
1827                 return len;
1828
1829         if (reg_msg.magic == LTTNG_UST_COMM_MAGIC) {
1830                 *byte_order = BYTE_ORDER == BIG_ENDIAN ?
1831                                 BIG_ENDIAN : LITTLE_ENDIAN;
1832         } else if (reg_msg.magic == bswap_32(LTTNG_UST_COMM_MAGIC)) {
1833                 *byte_order = BYTE_ORDER == BIG_ENDIAN ?
1834                                 LITTLE_ENDIAN : BIG_ENDIAN;
1835         } else {
1836                 return -LTTNG_UST_ERR_INVAL_MAGIC;
1837         }
1838         switch (reg_msg.socket_type) {
1839         case 0: *type = USTCTL_SOCKET_CMD;
1840                 break;
1841         case 1: *type = USTCTL_SOCKET_NOTIFY;
1842                 break;
1843         default:
1844                 return -LTTNG_UST_ERR_INVAL_SOCKET_TYPE;
1845         }
1846         *major = reg_msg.major;
1847         *minor = reg_msg.minor;
1848         *pid = reg_msg.pid;
1849         *ppid = reg_msg.ppid;
1850         *uid = reg_msg.uid;
1851         *gid = reg_msg.gid;
1852         *bits_per_long = reg_msg.bits_per_long;
1853         *uint8_t_alignment = reg_msg.uint8_t_alignment;
1854         *uint16_t_alignment = reg_msg.uint16_t_alignment;
1855         *uint32_t_alignment = reg_msg.uint32_t_alignment;
1856         *uint64_t_alignment = reg_msg.uint64_t_alignment;
1857         *long_alignment = reg_msg.long_alignment;
1858         memcpy(name, reg_msg.name, LTTNG_UST_ABI_PROCNAME_LEN);
1859         if (reg_msg.major != LTTNG_UST_ABI_MAJOR_VERSION) {
1860                 return -LTTNG_UST_ERR_UNSUP_MAJOR;
1861         }
1862
1863         return 0;
1864 }
1865
1866 int ustctl_recv_notify(int sock, enum ustctl_notify_cmd *notify_cmd)
1867 {
1868         struct ustcomm_notify_hdr header;
1869         ssize_t len;
1870
1871         len = ustcomm_recv_unix_sock(sock, &header, sizeof(header));
1872         if (len > 0 && len != sizeof(header))
1873                 return -EIO;
1874         if (len == 0)
1875                 return -EPIPE;
1876         if (len < 0)
1877                 return len;
1878         switch (header.notify_cmd) {
1879         case 0:
1880                 *notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
1881                 break;
1882         case 1:
1883                 *notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
1884                 break;
1885         case 2:
1886                 *notify_cmd = USTCTL_NOTIFY_CMD_ENUM;
1887                 break;
1888         default:
1889                 return -EINVAL;
1890         }
1891         return 0;
1892 }
1893
1894 /*
1895  * Returns 0 on success, negative error value on error.
1896  */
1897 int ustctl_recv_register_event(int sock,
1898         int *session_objd,
1899         int *channel_objd,
1900         char *event_name,
1901         int *loglevel,
1902         char **signature,
1903         size_t *nr_fields,
1904         struct ustctl_field **fields,
1905         char **model_emf_uri)
1906 {
1907         ssize_t len;
1908         struct ustcomm_notify_event_msg msg;
1909         size_t signature_len, fields_len, model_emf_uri_len;
1910         char *a_sign = NULL, *a_model_emf_uri = NULL;
1911         struct ustctl_field *a_fields = NULL;
1912
1913         len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
1914         if (len > 0 && len != sizeof(msg))
1915                 return -EIO;
1916         if (len == 0)
1917                 return -EPIPE;
1918         if (len < 0)
1919                 return len;
1920
1921         *session_objd = msg.session_objd;
1922         *channel_objd = msg.channel_objd;
1923         strncpy(event_name, msg.event_name, LTTNG_UST_SYM_NAME_LEN);
1924         event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
1925         *loglevel = msg.loglevel;
1926         signature_len = msg.signature_len;
1927         fields_len = msg.fields_len;
1928
1929         if (fields_len % sizeof(*a_fields) != 0) {
1930                 return -EINVAL;
1931         }
1932
1933         model_emf_uri_len = msg.model_emf_uri_len;
1934
1935         /* recv signature. contains at least \0. */
1936         a_sign = zmalloc(signature_len);
1937         if (!a_sign)
1938                 return -ENOMEM;
1939         len = ustcomm_recv_unix_sock(sock, a_sign, signature_len);
1940         if (len > 0 && len != signature_len) {
1941                 len = -EIO;
1942                 goto signature_error;
1943         }
1944         if (len == 0) {
1945                 len = -EPIPE;
1946                 goto signature_error;
1947         }
1948         if (len < 0) {
1949                 goto signature_error;
1950         }
1951         /* Enforce end of string */
1952         a_sign[signature_len - 1] = '\0';
1953
1954         /* recv fields */
1955         if (fields_len) {
1956                 a_fields = zmalloc(fields_len);
1957                 if (!a_fields) {
1958                         len = -ENOMEM;
1959                         goto signature_error;
1960                 }
1961                 len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
1962                 if (len > 0 && len != fields_len) {
1963                         len = -EIO;
1964                         goto fields_error;
1965                 }
1966                 if (len == 0) {
1967                         len = -EPIPE;
1968                         goto fields_error;
1969                 }
1970                 if (len < 0) {
1971                         goto fields_error;
1972                 }
1973         }
1974
1975         if (model_emf_uri_len) {
1976                 /* recv model_emf_uri_len */
1977                 a_model_emf_uri = zmalloc(model_emf_uri_len);
1978                 if (!a_model_emf_uri) {
1979                         len = -ENOMEM;
1980                         goto fields_error;
1981                 }
1982                 len = ustcomm_recv_unix_sock(sock, a_model_emf_uri,
1983                                 model_emf_uri_len);
1984                 if (len > 0 && len != model_emf_uri_len) {
1985                         len = -EIO;
1986                         goto model_error;
1987                 }
1988                 if (len == 0) {
1989                         len = -EPIPE;
1990                         goto model_error;
1991                 }
1992                 if (len < 0) {
1993                         goto model_error;
1994                 }
1995                 /* Enforce end of string */
1996                 a_model_emf_uri[model_emf_uri_len - 1] = '\0';
1997         }
1998
1999         *signature = a_sign;
2000         *nr_fields = fields_len / sizeof(*a_fields);
2001         *fields = a_fields;
2002         *model_emf_uri = a_model_emf_uri;
2003
2004         return 0;
2005
2006 model_error:
2007         free(a_model_emf_uri);
2008 fields_error:
2009         free(a_fields);
2010 signature_error:
2011         free(a_sign);
2012         return len;
2013 }
2014
2015 /*
2016  * Returns 0 on success, negative error value on error.
2017  */
2018 int ustctl_reply_register_event(int sock,
2019         uint32_t id,
2020         int ret_code)
2021 {
2022         ssize_t len;
2023         struct {
2024                 struct ustcomm_notify_hdr header;
2025                 struct ustcomm_notify_event_reply r;
2026         } reply;
2027
2028         memset(&reply, 0, sizeof(reply));
2029         reply.header.notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
2030         reply.r.ret_code = ret_code;
2031         reply.r.event_id = id;
2032         len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
2033         if (len > 0 && len != sizeof(reply))
2034                 return -EIO;
2035         if (len < 0)
2036                 return len;
2037         return 0;
2038 }
2039
2040 /*
2041  * Returns 0 on success, negative UST or system error value on error.
2042  */
2043 int ustctl_recv_register_enum(int sock,
2044         int *session_objd,
2045         char *enum_name,
2046         struct ustctl_enum_entry **entries,
2047         size_t *nr_entries)
2048 {
2049         ssize_t len;
2050         struct ustcomm_notify_enum_msg msg;
2051         size_t entries_len;
2052         struct ustctl_enum_entry *a_entries = NULL;
2053
2054         len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
2055         if (len > 0 && len != sizeof(msg))
2056                 return -EIO;
2057         if (len == 0)
2058                 return -EPIPE;
2059         if (len < 0)
2060                 return len;
2061
2062         *session_objd = msg.session_objd;
2063         strncpy(enum_name, msg.enum_name, LTTNG_UST_SYM_NAME_LEN);
2064         enum_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
2065         entries_len = msg.entries_len;
2066
2067         if (entries_len % sizeof(*a_entries) != 0) {
2068                 return -EINVAL;
2069         }
2070
2071         /* recv entries */
2072         if (entries_len) {
2073                 a_entries = zmalloc(entries_len);
2074                 if (!a_entries)
2075                         return -ENOMEM;
2076                 len = ustcomm_recv_unix_sock(sock, a_entries, entries_len);
2077                 if (len > 0 && len != entries_len) {
2078                         len = -EIO;
2079                         goto entries_error;
2080                 }
2081                 if (len == 0) {
2082                         len = -EPIPE;
2083                         goto entries_error;
2084                 }
2085                 if (len < 0) {
2086                         goto entries_error;
2087                 }
2088         }
2089         *nr_entries = entries_len / sizeof(*a_entries);
2090         *entries = a_entries;
2091
2092         return 0;
2093
2094 entries_error:
2095         free(a_entries);
2096         return len;
2097 }
2098
2099 /*
2100  * Returns 0 on success, negative error value on error.
2101  */
2102 int ustctl_reply_register_enum(int sock,
2103         uint64_t id,
2104         int ret_code)
2105 {
2106         ssize_t len;
2107         struct {
2108                 struct ustcomm_notify_hdr header;
2109                 struct ustcomm_notify_enum_reply r;
2110         } reply;
2111
2112         memset(&reply, 0, sizeof(reply));
2113         reply.header.notify_cmd = USTCTL_NOTIFY_CMD_ENUM;
2114         reply.r.ret_code = ret_code;
2115         reply.r.enum_id = id;
2116         len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
2117         if (len > 0 && len != sizeof(reply))
2118                 return -EIO;
2119         if (len < 0)
2120                 return len;
2121         return 0;
2122 }
2123
2124 /*
2125  * Returns 0 on success, negative UST or system error value on error.
2126  */
2127 int ustctl_recv_register_channel(int sock,
2128         int *session_objd,              /* session descriptor (output) */
2129         int *channel_objd,              /* channel descriptor (output) */
2130         size_t *nr_fields,
2131         struct ustctl_field **fields)
2132 {
2133         ssize_t len;
2134         struct ustcomm_notify_channel_msg msg;
2135         size_t fields_len;
2136         struct ustctl_field *a_fields;
2137
2138         len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
2139         if (len > 0 && len != sizeof(msg))
2140                 return -EIO;
2141         if (len == 0)
2142                 return -EPIPE;
2143         if (len < 0)
2144                 return len;
2145
2146         *session_objd = msg.session_objd;
2147         *channel_objd = msg.channel_objd;
2148         fields_len = msg.ctx_fields_len;
2149
2150         if (fields_len % sizeof(*a_fields) != 0) {
2151                 return -EINVAL;
2152         }
2153
2154         /* recv fields */
2155         if (fields_len) {
2156                 a_fields = zmalloc(fields_len);
2157                 if (!a_fields) {
2158                         len = -ENOMEM;
2159                         goto alloc_error;
2160                 }
2161                 len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
2162                 if (len > 0 && len != fields_len) {
2163                         len = -EIO;
2164                         goto fields_error;
2165                 }
2166                 if (len == 0) {
2167                         len = -EPIPE;
2168                         goto fields_error;
2169                 }
2170                 if (len < 0) {
2171                         goto fields_error;
2172                 }
2173                 *fields = a_fields;
2174         } else {
2175                 *fields = NULL;
2176         }
2177         *nr_fields = fields_len / sizeof(*a_fields);
2178         return 0;
2179
2180 fields_error:
2181         free(a_fields);
2182 alloc_error:
2183         return len;
2184 }
2185
2186 /*
2187  * Returns 0 on success, negative error value on error.
2188  */
2189 int ustctl_reply_register_channel(int sock,
2190         uint32_t chan_id,
2191         enum ustctl_channel_header header_type,
2192         int ret_code)
2193 {
2194         ssize_t len;
2195         struct {
2196                 struct ustcomm_notify_hdr header;
2197                 struct ustcomm_notify_channel_reply r;
2198         } reply;
2199
2200         memset(&reply, 0, sizeof(reply));
2201         reply.header.notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
2202         reply.r.ret_code = ret_code;
2203         reply.r.chan_id = chan_id;
2204         switch (header_type) {
2205         case USTCTL_CHANNEL_HEADER_COMPACT:
2206                 reply.r.header_type = 1;
2207                 break;
2208         case USTCTL_CHANNEL_HEADER_LARGE:
2209                 reply.r.header_type = 2;
2210                 break;
2211         default:
2212                 reply.r.header_type = 0;
2213                 break;
2214         }
2215         len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
2216         if (len > 0 && len != sizeof(reply))
2217                 return -EIO;
2218         if (len < 0)
2219                 return len;
2220         return 0;
2221 }
2222
2223 /* Regenerate the statedump. */
2224 int ustctl_regenerate_statedump(int sock, int handle)
2225 {
2226         struct ustcomm_ust_msg lum;
2227         struct ustcomm_ust_reply lur;
2228         int ret;
2229
2230         memset(&lum, 0, sizeof(lum));
2231         lum.handle = handle;
2232         lum.cmd = LTTNG_UST_SESSION_STATEDUMP;
2233         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
2234         if (ret)
2235                 return ret;
2236         DBG("Regenerated statedump for handle %u", handle);
2237         return 0;
2238 }
2239
2240 static __attribute__((constructor))
2241 void ustctl_init(void)
2242 {
2243         init_usterr();
2244         lttng_ust_getenv_init();        /* Needs init_usterr() to be completed. */
2245         lttng_ust_clock_init();
2246         lttng_ring_buffer_metadata_client_init();
2247         lttng_ring_buffer_client_overwrite_init();
2248         lttng_ring_buffer_client_overwrite_rt_init();
2249         lttng_ring_buffer_client_discard_init();
2250         lttng_ring_buffer_client_discard_rt_init();
2251         lib_ringbuffer_signal_init();
2252 }
2253
2254 static __attribute__((destructor))
2255 void ustctl_exit(void)
2256 {
2257         lttng_ring_buffer_client_discard_rt_exit();
2258         lttng_ring_buffer_client_discard_exit();
2259         lttng_ring_buffer_client_overwrite_rt_exit();
2260         lttng_ring_buffer_client_overwrite_exit();
2261         lttng_ring_buffer_metadata_client_exit();
2262 }