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 #include "../liblttng-ust/lttng-rb-clients.h"
  35
  36 /*
  37  * Number of milliseconds to retry before failing metadata writes on
  38  * buffer full condition. (10 seconds)
  39  */
  40 #define LTTNG_METADATA_TIMEOUT_MSEC     10000
  41
  42 /*
  43  * Channel representation within consumer.
  44  */
  45 struct ustctl_consumer_channel {
  46         struct lttng_channel *chan;             /* lttng channel buffers */
  47
  48         /* initial attributes */
  49         struct ustctl_consumer_channel_attr attr;
  50         int wait_fd;                            /* monitor close() */
  51         int wakeup_fd;                          /* monitor close() */
  52 };
  53
  54 /*
  55  * Stream representation within consumer.
  56  */
  57 struct ustctl_consumer_stream {
  58         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
  59         struct lttng_ust_lib_ring_buffer *buf;
  60         struct ustctl_consumer_channel *chan;
  61         int shm_fd, wait_fd, wakeup_fd;
  62         int cpu;
  63         uint64_t memory_map_size;
  64 };
  65
  66 extern void lttng_ring_buffer_client_overwrite_init(void);
  67 extern void lttng_ring_buffer_client_overwrite_rt_init(void);
  68 extern void lttng_ring_buffer_client_discard_init(void);
  69 extern void lttng_ring_buffer_client_discard_rt_init(void);
  70 extern void lttng_ring_buffer_metadata_client_init(void);
  71 extern void lttng_ring_buffer_client_overwrite_exit(void);
  72 extern void lttng_ring_buffer_client_overwrite_rt_exit(void);
  73 extern void lttng_ring_buffer_client_discard_exit(void);
  74 extern void lttng_ring_buffer_client_discard_rt_exit(void);
  75 extern void lttng_ring_buffer_metadata_client_exit(void);
  76
  77 volatile enum ust_loglevel ust_loglevel;
  78
  79 int ustctl_release_handle(int sock, int handle)
  80 {
  81         struct ustcomm_ust_msg lum;
  82         struct ustcomm_ust_reply lur;
  83
  84         if (sock < 0 || handle < 0)
  85                 return 0;
  86         memset(&lum, 0, sizeof(lum));
  87         lum.handle = handle;
  88         lum.cmd = LTTNG_UST_RELEASE;
  89         return ustcomm_send_app_cmd(sock, &lum, &lur);
  90 }
  91
  92 /*
  93  * If sock is negative, it means we don't have to notify the other side
  94  * (e.g. application has already vanished).
  95  */
  96 int ustctl_release_object(int sock, struct lttng_ust_object_data *data)
  97 {
  98         int ret;
  99
 100         if (!data)
 101                 return -EINVAL;
 102
 103         switch (data->type) {
 104         case LTTNG_UST_OBJECT_TYPE_CHANNEL:
 105                 if (data->u.channel.wakeup_fd >= 0) {
 106                         ret = close(data->u.channel.wakeup_fd);
 107                         if (ret < 0) {
 108                                 ret = -errno;
 109                                 return ret;
 110                         }
 111                 }
 112                 free(data->u.channel.data);
 113                 break;
 114         case LTTNG_UST_OBJECT_TYPE_STREAM:
 115                 if (data->u.stream.shm_fd >= 0) {
 116                         ret = close(data->u.stream.shm_fd);
 117                         if (ret < 0) {
 118                                 ret = -errno;
 119                                 return ret;
 120                         }
 121                 }
 122                 if (data->u.stream.wakeup_fd >= 0) {
 123                         ret = close(data->u.stream.wakeup_fd);
 124                         if (ret < 0) {
 125                                 ret = -errno;
 126                                 return ret;
 127                         }
 128                 }
 129                 break;
 130         case LTTNG_UST_OBJECT_TYPE_EVENT:
 131         case LTTNG_UST_OBJECT_TYPE_CONTEXT:
 132                 break;
 133         default:
 134                 assert(0);
 135         }
 136         return ustctl_release_handle(sock, data->handle);
 137 }
 138
 139 /*
 140  * Send registration done packet to the application.
 141  */
 142 int ustctl_register_done(int sock)
 143 {
 144         struct ustcomm_ust_msg lum;
 145         struct ustcomm_ust_reply lur;
 146         int ret;
 147
 148         DBG("Sending register done command to %d", sock);
 149         memset(&lum, 0, sizeof(lum));
 150         lum.handle = LTTNG_UST_ROOT_HANDLE;
 151         lum.cmd = LTTNG_UST_REGISTER_DONE;
 152         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 153         if (ret)
 154                 return ret;
 155         return 0;
 156 }
 157
 158 /*
 159  * returns session handle.
 160  */
 161 int ustctl_create_session(int sock)
 162 {
 163         struct ustcomm_ust_msg lum;
 164         struct ustcomm_ust_reply lur;
 165         int ret, session_handle;
 166
 167         /* Create session */
 168         memset(&lum, 0, sizeof(lum));
 169         lum.handle = LTTNG_UST_ROOT_HANDLE;
 170         lum.cmd = LTTNG_UST_SESSION;
 171         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 172         if (ret)
 173                 return ret;
 174         session_handle = lur.ret_val;
 175         DBG("received session handle %u", session_handle);
 176         return session_handle;
 177 }
 178
 179 int ustctl_create_event(int sock, struct lttng_ust_event *ev,
 180                 struct lttng_ust_object_data *channel_data,
 181                 struct lttng_ust_object_data **_event_data)
 182 {
 183         struct ustcomm_ust_msg lum;
 184         struct ustcomm_ust_reply lur;
 185         struct lttng_ust_object_data *event_data;
 186         int ret;
 187
 188         if (!channel_data || !_event_data)
 189                 return -EINVAL;
 190
 191         event_data = zmalloc(sizeof(*event_data));
 192         if (!event_data)
 193                 return -ENOMEM;
 194         event_data->type = LTTNG_UST_OBJECT_TYPE_EVENT;
 195         memset(&lum, 0, sizeof(lum));
 196         lum.handle = channel_data->handle;
 197         lum.cmd = LTTNG_UST_EVENT;
 198         strncpy(lum.u.event.name, ev->name,
 199                 LTTNG_UST_SYM_NAME_LEN);
 200         lum.u.event.instrumentation = ev->instrumentation;
 201         lum.u.event.loglevel_type = ev->loglevel_type;
 202         lum.u.event.loglevel = ev->loglevel;
 203         lum.u.event.disabled = ev->disabled;
 204         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 205         if (ret) {
 206                 free(event_data);
 207                 return ret;
 208         }
 209         event_data->handle = lur.ret_val;
 210         DBG("received event handle %u", event_data->handle);
 211         *_event_data = event_data;
 212         return 0;
 213 }
 214
 215 int ustctl_add_context(int sock, struct lttng_ust_context *ctx,
 216                 struct lttng_ust_object_data *obj_data,
 217                 struct lttng_ust_object_data **_context_data)
 218 {
 219         struct ustcomm_ust_msg lum;
 220         struct ustcomm_ust_reply lur;
 221         struct lttng_ust_object_data *context_data;
 222         int ret;
 223
 224         if (!obj_data || !_context_data)
 225                 return -EINVAL;
 226
 227         context_data = zmalloc(sizeof(*context_data));
 228         if (!context_data)
 229                 return -ENOMEM;
 230         context_data->type = LTTNG_UST_OBJECT_TYPE_CONTEXT;
 231         memset(&lum, 0, sizeof(lum));
 232         lum.handle = obj_data->handle;
 233         lum.cmd = LTTNG_UST_CONTEXT;
 234         lum.u.context = *ctx;
 235         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 236         if (ret) {
 237                 free(context_data);
 238                 return ret;
 239         }
 240         context_data->handle = -1;
 241         DBG("Context created successfully");
 242         *_context_data = context_data;
 243         return ret;
 244 }
 245
 246 int ustctl_set_filter(int sock, struct lttng_ust_filter_bytecode *bytecode,
 247                 struct lttng_ust_object_data *obj_data)
 248 {
 249         struct ustcomm_ust_msg lum;
 250         struct ustcomm_ust_reply lur;
 251         int ret;
 252
 253         if (!obj_data)
 254                 return -EINVAL;
 255
 256         memset(&lum, 0, sizeof(lum));
 257         lum.handle = obj_data->handle;
 258         lum.cmd = LTTNG_UST_FILTER;
 259         lum.u.filter.data_size = bytecode->len;
 260         lum.u.filter.reloc_offset = bytecode->reloc_offset;
 261         lum.u.filter.seqnum = bytecode->seqnum;
 262
 263         ret = ustcomm_send_app_msg(sock, &lum);
 264         if (ret)
 265                 return ret;
 266         /* send var len bytecode */
 267         ret = ustcomm_send_unix_sock(sock, bytecode->data,
 268                                 bytecode->len);
 269         if (ret < 0) {
 270                 return ret;
 271         }
 272         if (ret != bytecode->len)
 273                 return -EINVAL;
 274         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 275 }
 276
 277 int ustctl_set_exclusion(int sock, struct lttng_ust_event_exclusion *exclusion,
 278                 struct lttng_ust_object_data *obj_data)
 279 {
 280         struct ustcomm_ust_msg lum;
 281         struct ustcomm_ust_reply lur;
 282         int ret;
 283
 284         if (!obj_data) {
 285                 return -EINVAL;
 286         }
 287
 288         memset(&lum, 0, sizeof(lum));
 289         lum.handle = obj_data->handle;
 290         lum.cmd = LTTNG_UST_EXCLUSION;
 291         lum.u.exclusion.count = exclusion->count;
 292
 293         ret = ustcomm_send_app_msg(sock, &lum);
 294         if (ret) {
 295                 return ret;
 296         }
 297
 298         /* send var len exclusion names */
 299         ret = ustcomm_send_unix_sock(sock,
 300                         exclusion->names,
 301                         exclusion->count * LTTNG_UST_SYM_NAME_LEN);
 302         if (ret < 0) {
 303                 return ret;
 304         }
 305         if (ret != exclusion->count * LTTNG_UST_SYM_NAME_LEN) {
 306                 return -EINVAL;
 307         }
 308         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 309 }
 310
 311 /* Enable event, channel and session ioctl */
 312 int ustctl_enable(int sock, struct lttng_ust_object_data *object)
 313 {
 314         struct ustcomm_ust_msg lum;
 315         struct ustcomm_ust_reply lur;
 316         int ret;
 317
 318         if (!object)
 319                 return -EINVAL;
 320
 321         memset(&lum, 0, sizeof(lum));
 322         lum.handle = object->handle;
 323         lum.cmd = LTTNG_UST_ENABLE;
 324         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 325         if (ret)
 326                 return ret;
 327         DBG("enabled handle %u", object->handle);
 328         return 0;
 329 }
 330
 331 /* Disable event, channel and session ioctl */
 332 int ustctl_disable(int sock, struct lttng_ust_object_data *object)
 333 {
 334         struct ustcomm_ust_msg lum;
 335         struct ustcomm_ust_reply lur;
 336         int ret;
 337
 338         if (!object)
 339                 return -EINVAL;
 340
 341         memset(&lum, 0, sizeof(lum));
 342         lum.handle = object->handle;
 343         lum.cmd = LTTNG_UST_DISABLE;
 344         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 345         if (ret)
 346                 return ret;
 347         DBG("disable handle %u", object->handle);
 348         return 0;
 349 }
 350
 351 int ustctl_start_session(int sock, int handle)
 352 {
 353         struct lttng_ust_object_data obj;
 354
 355         obj.handle = handle;
 356         return ustctl_enable(sock, &obj);
 357 }
 358
 359 int ustctl_stop_session(int sock, int handle)
 360 {
 361         struct lttng_ust_object_data obj;
 362
 363         obj.handle = handle;
 364         return ustctl_disable(sock, &obj);
 365 }
 366
 367 int ustctl_tracepoint_list(int sock)
 368 {
 369         struct ustcomm_ust_msg lum;
 370         struct ustcomm_ust_reply lur;
 371         int ret, tp_list_handle;
 372
 373         memset(&lum, 0, sizeof(lum));
 374         lum.handle = LTTNG_UST_ROOT_HANDLE;
 375         lum.cmd = LTTNG_UST_TRACEPOINT_LIST;
 376         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 377         if (ret)
 378                 return ret;
 379         tp_list_handle = lur.ret_val;
 380         DBG("received tracepoint list handle %u", tp_list_handle);
 381         return tp_list_handle;
 382 }
 383
 384 int ustctl_tracepoint_list_get(int sock, int tp_list_handle,
 385                 struct lttng_ust_tracepoint_iter *iter)
 386 {
 387         struct ustcomm_ust_msg lum;
 388         struct ustcomm_ust_reply lur;
 389         int ret;
 390
 391         if (!iter)
 392                 return -EINVAL;
 393
 394         memset(&lum, 0, sizeof(lum));
 395         lum.handle = tp_list_handle;
 396         lum.cmd = LTTNG_UST_TRACEPOINT_LIST_GET;
 397         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 398         if (ret)
 399                 return ret;
 400         DBG("received tracepoint list entry name %s loglevel %d",
 401                 lur.u.tracepoint.name,
 402                 lur.u.tracepoint.loglevel);
 403         memcpy(iter, &lur.u.tracepoint, sizeof(*iter));
 404         return 0;
 405 }
 406
 407 int ustctl_tracepoint_field_list(int sock)
 408 {
 409         struct ustcomm_ust_msg lum;
 410         struct ustcomm_ust_reply lur;
 411         int ret, tp_field_list_handle;
 412
 413         memset(&lum, 0, sizeof(lum));
 414         lum.handle = LTTNG_UST_ROOT_HANDLE;
 415         lum.cmd = LTTNG_UST_TRACEPOINT_FIELD_LIST;
 416         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 417         if (ret)
 418                 return ret;
 419         tp_field_list_handle = lur.ret_val;
 420         DBG("received tracepoint field list handle %u", tp_field_list_handle);
 421         return tp_field_list_handle;
 422 }
 423
 424 int ustctl_tracepoint_field_list_get(int sock, int tp_field_list_handle,
 425                 struct lttng_ust_field_iter *iter)
 426 {
 427         struct ustcomm_ust_msg lum;
 428         struct ustcomm_ust_reply lur;
 429         int ret;
 430         ssize_t len;
 431
 432         if (!iter)
 433                 return -EINVAL;
 434
 435         memset(&lum, 0, sizeof(lum));
 436         lum.handle = tp_field_list_handle;
 437         lum.cmd = LTTNG_UST_TRACEPOINT_FIELD_LIST_GET;
 438         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 439         if (ret)
 440                 return ret;
 441         len = ustcomm_recv_unix_sock(sock, iter, sizeof(*iter));
 442         if (len != sizeof(*iter)) {
 443                 return -EINVAL;
 444         }
 445         DBG("received tracepoint field list entry event_name %s event_loglevel %d field_name %s field_type %d",
 446                 iter->event_name,
 447                 iter->loglevel,
 448                 iter->field_name,
 449                 iter->type);
 450         return 0;
 451 }
 452
 453 int ustctl_tracer_version(int sock, struct lttng_ust_tracer_version *v)
 454 {
 455         struct ustcomm_ust_msg lum;
 456         struct ustcomm_ust_reply lur;
 457         int ret;
 458
 459         if (!v)
 460                 return -EINVAL;
 461
 462         memset(&lum, 0, sizeof(lum));
 463         lum.handle = LTTNG_UST_ROOT_HANDLE;
 464         lum.cmd = LTTNG_UST_TRACER_VERSION;
 465         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 466         if (ret)
 467                 return ret;
 468         memcpy(v, &lur.u.version, sizeof(*v));
 469         DBG("received tracer version");
 470         return 0;
 471 }
 472
 473 int ustctl_wait_quiescent(int sock)
 474 {
 475         struct ustcomm_ust_msg lum;
 476         struct ustcomm_ust_reply lur;
 477         int ret;
 478
 479         memset(&lum, 0, sizeof(lum));
 480         lum.handle = LTTNG_UST_ROOT_HANDLE;
 481         lum.cmd = LTTNG_UST_WAIT_QUIESCENT;
 482         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 483         if (ret)
 484                 return ret;
 485         DBG("waited for quiescent state");
 486         return 0;
 487 }
 488
 489 int ustctl_calibrate(int sock, struct lttng_ust_calibrate *calibrate)
 490 {
 491         if (!calibrate)
 492                 return -EINVAL;
 493
 494         return -ENOSYS;
 495 }
 496
 497 int ustctl_sock_flush_buffer(int sock, struct lttng_ust_object_data *object)
 498 {
 499         struct ustcomm_ust_msg lum;
 500         struct ustcomm_ust_reply lur;
 501         int ret;
 502
 503         if (!object)
 504                 return -EINVAL;
 505
 506         memset(&lum, 0, sizeof(lum));
 507         lum.handle = object->handle;
 508         lum.cmd = LTTNG_UST_FLUSH_BUFFER;
 509         ret = ustcomm_send_app_cmd(sock, &lum, &lur);
 510         if (ret)
 511                 return ret;
 512         DBG("flushed buffer handle %u", object->handle);
 513         return 0;
 514 }
 515
 516 static
 517 int ustctl_send_channel(int sock,
 518                 enum lttng_ust_chan_type type,
 519                 void *data,
 520                 uint64_t size,
 521                 int wakeup_fd,
 522                 int send_fd_only)
 523 {
 524         ssize_t len;
 525
 526         if (!send_fd_only) {
 527                 /* Send mmap size */
 528                 len = ustcomm_send_unix_sock(sock, &size, sizeof(size));
 529                 if (len != sizeof(size)) {
 530                         if (len < 0)
 531                                 return len;
 532                         else
 533                                 return -EIO;
 534                 }
 535
 536                 /* Send channel type */
 537                 len = ustcomm_send_unix_sock(sock, &type, sizeof(type));
 538                 if (len != sizeof(type)) {
 539                         if (len < 0)
 540                                 return len;
 541                         else
 542                                 return -EIO;
 543                 }
 544         }
 545
 546         /* Send channel data */
 547         len = ustcomm_send_unix_sock(sock, data, size);
 548         if (len != size) {
 549                 if (len < 0)
 550                         return len;
 551                 else
 552                         return -EIO;
 553         }
 554
 555         /* Send wakeup fd */
 556         len = ustcomm_send_fds_unix_sock(sock, &wakeup_fd, 1);
 557         if (len <= 0) {
 558                 if (len < 0)
 559                         return len;
 560                 else
 561                         return -EIO;
 562         }
 563         return 0;
 564 }
 565
 566 static
 567 int ustctl_send_stream(int sock,
 568                 uint32_t stream_nr,
 569                 uint64_t memory_map_size,
 570                 int shm_fd, int wakeup_fd,
 571                 int send_fd_only)
 572 {
 573         ssize_t len;
 574         int fds[2];
 575
 576         if (!send_fd_only) {
 577                 if (shm_fd < 0) {
 578                         /* finish iteration */
 579                         uint64_t v = -1;
 580
 581                         len = ustcomm_send_unix_sock(sock, &v, sizeof(v));
 582                         if (len != sizeof(v)) {
 583                                 if (len < 0)
 584                                         return len;
 585                                 else
 586                                         return -EIO;
 587                         }
 588                         return 0;
 589                 }
 590
 591                 /* Send mmap size */
 592                 len = ustcomm_send_unix_sock(sock, &memory_map_size,
 593                         sizeof(memory_map_size));
 594                 if (len != sizeof(memory_map_size)) {
 595                         if (len < 0)
 596                                 return len;
 597                         else
 598                                 return -EIO;
 599                 }
 600
 601                 /* Send stream nr */
 602                 len = ustcomm_send_unix_sock(sock, &stream_nr,
 603                         sizeof(stream_nr));
 604                 if (len != sizeof(stream_nr)) {
 605                         if (len < 0)
 606                                 return len;
 607                         else
 608                                 return -EIO;
 609                 }
 610         }
 611
 612         /* Send shm fd and wakeup fd */
 613         fds[0] = shm_fd;
 614         fds[1] = wakeup_fd;
 615         len = ustcomm_send_fds_unix_sock(sock, fds, 2);
 616         if (len <= 0) {
 617                 if (len < 0)
 618                         return len;
 619                 else
 620                         return -EIO;
 621         }
 622         return 0;
 623 }
 624
 625 int ustctl_recv_channel_from_consumer(int sock,
 626                 struct lttng_ust_object_data **_channel_data)
 627 {
 628         struct lttng_ust_object_data *channel_data;
 629         ssize_t len;
 630         int wakeup_fd;
 631         int ret;
 632
 633         channel_data = zmalloc(sizeof(*channel_data));
 634         if (!channel_data) {
 635                 ret = -ENOMEM;
 636                 goto error_alloc;
 637         }
 638         channel_data->type = LTTNG_UST_OBJECT_TYPE_CHANNEL;
 639         channel_data->handle = -1;
 640
 641         /* recv mmap size */
 642         len = ustcomm_recv_unix_sock(sock, &channel_data->size,
 643                         sizeof(channel_data->size));
 644         if (len != sizeof(channel_data->size)) {
 645                 if (len < 0)
 646                         ret = len;
 647                 else
 648                         ret = -EINVAL;
 649                 goto error;
 650         }
 651
 652         /* recv channel type */
 653         len = ustcomm_recv_unix_sock(sock, &channel_data->u.channel.type,
 654                         sizeof(channel_data->u.channel.type));
 655         if (len != sizeof(channel_data->u.channel.type)) {
 656                 if (len < 0)
 657                         ret = len;
 658                 else
 659                         ret = -EINVAL;
 660                 goto error;
 661         }
 662
 663         /* recv channel data */
 664         channel_data->u.channel.data = zmalloc(channel_data->size);
 665         if (!channel_data->u.channel.data) {
 666                 ret = -ENOMEM;
 667                 goto error;
 668         }
 669         len = ustcomm_recv_unix_sock(sock, channel_data->u.channel.data,
 670                         channel_data->size);
 671         if (len != channel_data->size) {
 672                 if (len < 0)
 673                         ret = len;
 674                 else
 675                         ret = -EINVAL;
 676                 goto error_recv_data;
 677         }
 678         /* recv wakeup fd */
 679         len = ustcomm_recv_fds_unix_sock(sock, &wakeup_fd, 1);
 680         if (len <= 0) {
 681                 if (len < 0) {
 682                         ret = len;
 683                         goto error_recv_data;
 684                 } else {
 685                         ret = -EIO;
 686                         goto error_recv_data;
 687                 }
 688         }
 689         channel_data->u.channel.wakeup_fd = wakeup_fd;
 690         *_channel_data = channel_data;
 691         return 0;
 692
 693 error_recv_data:
 694         free(channel_data->u.channel.data);
 695 error:
 696         free(channel_data);
 697 error_alloc:
 698         return ret;
 699 }
 700
 701 int ustctl_recv_stream_from_consumer(int sock,
 702                 struct lttng_ust_object_data **_stream_data)
 703 {
 704         struct lttng_ust_object_data *stream_data;
 705         ssize_t len;
 706         int ret;
 707         int fds[2];
 708
 709         stream_data = zmalloc(sizeof(*stream_data));
 710         if (!stream_data) {
 711                 ret = -ENOMEM;
 712                 goto error_alloc;
 713         }
 714
 715         stream_data->type = LTTNG_UST_OBJECT_TYPE_STREAM;
 716         stream_data->handle = -1;
 717
 718         /* recv mmap size */
 719         len = ustcomm_recv_unix_sock(sock, &stream_data->size,
 720                         sizeof(stream_data->size));
 721         if (len != sizeof(stream_data->size)) {
 722                 if (len < 0)
 723                         ret = len;
 724                 else
 725                         ret = -EINVAL;
 726                 goto error;
 727         }
 728         if (stream_data->size == -1) {
 729                 ret = -LTTNG_UST_ERR_NOENT;
 730                 goto error;
 731         }
 732
 733         /* recv stream nr */
 734         len = ustcomm_recv_unix_sock(sock, &stream_data->u.stream.stream_nr,
 735                         sizeof(stream_data->u.stream.stream_nr));
 736         if (len != sizeof(stream_data->u.stream.stream_nr)) {
 737                 if (len < 0)
 738                         ret = len;
 739                 else
 740                         ret = -EINVAL;
 741                 goto error;
 742         }
 743
 744         /* recv shm fd and wakeup fd */
 745         len = ustcomm_recv_fds_unix_sock(sock, fds, 2);
 746         if (len <= 0) {
 747                 if (len < 0) {
 748                         ret = len;
 749                         goto error;
 750                 } else {
 751                         ret = -EIO;
 752                         goto error;
 753                 }
 754         }
 755         stream_data->u.stream.shm_fd = fds[0];
 756         stream_data->u.stream.wakeup_fd = fds[1];
 757         *_stream_data = stream_data;
 758         return 0;
 759
 760 error:
 761         free(stream_data);
 762 error_alloc:
 763         return ret;
 764 }
 765
 766 int ustctl_send_channel_to_ust(int sock, int session_handle,
 767                 struct lttng_ust_object_data *channel_data)
 768 {
 769         struct ustcomm_ust_msg lum;
 770         struct ustcomm_ust_reply lur;
 771         int ret;
 772
 773         if (!channel_data)
 774                 return -EINVAL;
 775
 776         memset(&lum, 0, sizeof(lum));
 777         lum.handle = session_handle;
 778         lum.cmd = LTTNG_UST_CHANNEL;
 779         lum.u.channel.len = channel_data->size;
 780         lum.u.channel.type = channel_data->u.channel.type;
 781         ret = ustcomm_send_app_msg(sock, &lum);
 782         if (ret)
 783                 return ret;
 784
 785         ret = ustctl_send_channel(sock,
 786                         channel_data->u.channel.type,
 787                         channel_data->u.channel.data,
 788                         channel_data->size,
 789                         channel_data->u.channel.wakeup_fd,
 790                         1);
 791         if (ret)
 792                 return ret;
 793         ret = ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 794         if (!ret) {
 795                 channel_data->handle = lur.ret_val;
 796         }
 797         return ret;
 798 }
 799
 800 int ustctl_send_stream_to_ust(int sock,
 801                 struct lttng_ust_object_data *channel_data,
 802                 struct lttng_ust_object_data *stream_data)
 803 {
 804         struct ustcomm_ust_msg lum;
 805         struct ustcomm_ust_reply lur;
 806         int ret;
 807
 808         memset(&lum, 0, sizeof(lum));
 809         lum.handle = channel_data->handle;
 810         lum.cmd = LTTNG_UST_STREAM;
 811         lum.u.stream.len = stream_data->size;
 812         lum.u.stream.stream_nr = stream_data->u.stream.stream_nr;
 813         ret = ustcomm_send_app_msg(sock, &lum);
 814         if (ret)
 815                 return ret;
 816
 817         assert(stream_data);
 818         assert(stream_data->type == LTTNG_UST_OBJECT_TYPE_STREAM);
 819
 820         ret = ustctl_send_stream(sock,
 821                         stream_data->u.stream.stream_nr,
 822                         stream_data->size,
 823                         stream_data->u.stream.shm_fd,
 824                         stream_data->u.stream.wakeup_fd, 1);
 825         if (ret)
 826                 return ret;
 827         return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 828 }
 829
 830 int ustctl_duplicate_ust_object_data(struct lttng_ust_object_data **dest,
 831                 struct lttng_ust_object_data *src)
 832 {
 833         struct lttng_ust_object_data *obj;
 834         int ret;
 835
 836         if (src->handle != -1) {
 837                 ret = -EINVAL;
 838                 goto error;
 839         }
 840
 841         obj = zmalloc(sizeof(*obj));
 842         if (!obj) {
 843                 ret = -ENOMEM;
 844                 goto error;
 845         }
 846
 847         obj->type = src->type;
 848         obj->handle = src->handle;
 849         obj->size = src->size;
 850
 851         switch (obj->type) {
 852         case LTTNG_UST_OBJECT_TYPE_CHANNEL:
 853         {
 854                 obj->u.channel.type = src->u.channel.type;
 855                 if (src->u.channel.wakeup_fd >= 0) {
 856                         obj->u.channel.wakeup_fd =
 857                                 dup(src->u.channel.wakeup_fd);
 858                         if (obj->u.channel.wakeup_fd < 0) {
 859                                 ret = errno;
 860                                 goto chan_error_wakeup_fd;
 861                         }
 862                 } else {
 863                         obj->u.channel.wakeup_fd =
 864                                 src->u.channel.wakeup_fd;
 865                 }
 866                 obj->u.channel.data = zmalloc(obj->size);
 867                 if (!obj->u.channel.data) {
 868                         ret = -ENOMEM;
 869                         goto chan_error_alloc;
 870                 }
 871                 memcpy(obj->u.channel.data, src->u.channel.data, obj->size);
 872                 break;
 873
 874         chan_error_alloc:
 875                 if (src->u.channel.wakeup_fd >= 0) {
 876                         int closeret;
 877
 878                         closeret = close(obj->u.channel.wakeup_fd);
 879                         if (closeret) {
 880                                 PERROR("close");
 881                         }
 882                 }
 883         chan_error_wakeup_fd:
 884                 goto error_type;
 885
 886         }
 887
 888         case LTTNG_UST_OBJECT_TYPE_STREAM:
 889         {
 890                 obj->u.stream.stream_nr = src->u.stream.stream_nr;
 891                 if (src->u.stream.wakeup_fd >= 0) {
 892                         obj->u.stream.wakeup_fd =
 893                                 dup(src->u.stream.wakeup_fd);
 894                         if (obj->u.stream.wakeup_fd < 0) {
 895                                 ret = errno;
 896                                 goto stream_error_wakeup_fd;
 897                         }
 898                 } else {
 899                         obj->u.stream.wakeup_fd =
 900                                 src->u.stream.wakeup_fd;
 901                 }
 902
 903                 if (src->u.stream.shm_fd >= 0) {
 904                         obj->u.stream.shm_fd =
 905                                 dup(src->u.stream.shm_fd);
 906                         if (obj->u.stream.shm_fd < 0) {
 907                                 ret = errno;
 908                                 goto stream_error_shm_fd;
 909                         }
 910                 } else {
 911                         obj->u.stream.shm_fd =
 912                                 src->u.stream.shm_fd;
 913                 }
 914                 break;
 915
 916         stream_error_shm_fd:
 917                 if (src->u.stream.wakeup_fd >= 0) {
 918                         int closeret;
 919
 920                         closeret = close(obj->u.stream.wakeup_fd);
 921                         if (closeret) {
 922                                 PERROR("close");
 923                         }
 924                 }
 925         stream_error_wakeup_fd:
 926                 goto error_type;
 927         }
 928
 929         default:
 930                 ret = -EINVAL;
 931                 goto error_type;
 932         }
 933
 934         *dest = obj;
 935         return 0;
 936
 937 error_type:
 938         free(obj);
 939 error:
 940         return ret;
 941 }
 942
 943
 944 /* Buffer operations */
 945
 946 struct ustctl_consumer_channel *
 947         ustctl_create_channel(struct ustctl_consumer_channel_attr *attr)
 948 {
 949         struct ustctl_consumer_channel *chan;
 950         const char *transport_name;
 951         struct lttng_transport *transport;
 952
 953         switch (attr->type) {
 954         case LTTNG_UST_CHAN_PER_CPU:
 955                 if (attr->output == LTTNG_UST_MMAP) {
 956                         if (attr->overwrite) {
 957                                 if (attr->read_timer_interval == 0) {
 958                                         transport_name = "relay-overwrite-mmap";
 959                                 } else {
 960                                         transport_name = "relay-overwrite-rt-mmap";
 961                                 }
 962                         } else {
 963                                 if (attr->read_timer_interval == 0) {
 964                                         transport_name = "relay-discard-mmap";
 965                                 } else {
 966                                         transport_name = "relay-discard-rt-mmap";
 967                                 }
 968                         }
 969                 } else {
 970                         return NULL;
 971                 }
 972                 break;
 973         case LTTNG_UST_CHAN_METADATA:
 974                 if (attr->output == LTTNG_UST_MMAP)
 975                         transport_name = "relay-metadata-mmap";
 976                 else
 977                         return NULL;
 978                 break;
 979         default:
 980                 transport_name = "<unknown>";
 981                 return NULL;
 982         }
 983
 984         transport = lttng_transport_find(transport_name);
 985         if (!transport) {
 986                 DBG("LTTng transport %s not found\n",
 987                         transport_name);
 988                 return NULL;
 989         }
 990
 991         chan = zmalloc(sizeof(*chan));
 992         if (!chan)
 993                 return NULL;
 994
 995         chan->chan = transport->ops.channel_create(transport_name, NULL,
 996                         attr->subbuf_size, attr->num_subbuf,
 997                         attr->switch_timer_interval,
 998                         attr->read_timer_interval,
 999                         attr->uuid, attr->chan_id);
1000         if (!chan->chan) {
1001                 goto chan_error;
1002         }
1003         chan->chan->ops = &transport->ops;
1004         memcpy(&chan->attr, attr, sizeof(chan->attr));
1005         chan->wait_fd = ustctl_channel_get_wait_fd(chan);
1006         chan->wakeup_fd = ustctl_channel_get_wakeup_fd(chan);
1007         return chan;
1008
1009 chan_error:
1010         free(chan);
1011         return NULL;
1012 }
1013
1014 void ustctl_destroy_channel(struct ustctl_consumer_channel *chan)
1015 {
1016         (void) ustctl_channel_close_wait_fd(chan);
1017         (void) ustctl_channel_close_wakeup_fd(chan);
1018         chan->chan->ops->channel_destroy(chan->chan);
1019         free(chan);
1020 }
1021
1022 int ustctl_send_channel_to_sessiond(int sock,
1023                 struct ustctl_consumer_channel *channel)
1024 {
1025         struct shm_object_table *table;
1026
1027         table = channel->chan->handle->table;
1028         if (table->size <= 0)
1029                 return -EINVAL;
1030         return ustctl_send_channel(sock,
1031                         channel->attr.type,
1032                         table->objects[0].memory_map,
1033                         table->objects[0].memory_map_size,
1034                         channel->wakeup_fd,
1035                         0);
1036 }
1037
1038 int ustctl_send_stream_to_sessiond(int sock,
1039                 struct ustctl_consumer_stream *stream)
1040 {
1041         if (!stream)
1042                 return ustctl_send_stream(sock, -1U, -1U, -1, -1, 0);
1043
1044         return ustctl_send_stream(sock,
1045                         stream->cpu,
1046                         stream->memory_map_size,
1047                         stream->shm_fd, stream->wakeup_fd,
1048                         0);
1049 }
1050
1051 int ustctl_write_metadata_to_channel(
1052                 struct ustctl_consumer_channel *channel,
1053                 const char *metadata_str,       /* NOT null-terminated */
1054                 size_t len)                     /* metadata length */
1055 {
1056         struct lttng_ust_lib_ring_buffer_ctx ctx;
1057         struct lttng_channel *chan = channel->chan;
1058         const char *str = metadata_str;
1059         int ret = 0, waitret;
1060         size_t reserve_len, pos;
1061
1062         for (pos = 0; pos < len; pos += reserve_len) {
1063                 reserve_len = min_t(size_t,
1064                                 chan->ops->packet_avail_size(chan->chan, chan->handle),
1065                                 len - pos);
1066                 lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
1067                                          sizeof(char), -1, chan->handle);
1068                 /*
1069                  * We don't care about metadata buffer's records lost
1070                  * count, because we always retry here. Report error if
1071                  * we need to bail out after timeout or being
1072                  * interrupted.
1073                  */
1074                 waitret = wait_cond_interruptible_timeout(
1075                         ({
1076                                 ret = chan->ops->event_reserve(&ctx, 0);
1077                                 ret != -ENOBUFS || !ret;
1078                         }),
1079                         LTTNG_METADATA_TIMEOUT_MSEC);
1080                 if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) {
1081                         DBG("LTTng: Failure to write metadata to buffers (%s)\n",
1082                                 waitret == -EINTR ? "interrupted" :
1083                                         (ret == -ENOBUFS ? "timeout" : "I/O error"));
1084                         if (waitret == -EINTR)
1085                                 ret = waitret;
1086                         goto end;
1087                 }
1088                 chan->ops->event_write(&ctx, &str[pos], reserve_len);
1089                 chan->ops->event_commit(&ctx);
1090         }
1091 end:
1092         return ret;
1093 }
1094
1095 /*
1096  * Write at most one packet in the channel.
1097  * Returns the number of bytes written on success, < 0 on error.
1098  */
1099 ssize_t ustctl_write_one_packet_to_channel(
1100                 struct ustctl_consumer_channel *channel,
1101                 const char *metadata_str,       /* NOT null-terminated */
1102                 size_t len)                     /* metadata length */
1103 {
1104         struct lttng_ust_lib_ring_buffer_ctx ctx;
1105         struct lttng_channel *chan = channel->chan;
1106         const char *str = metadata_str;
1107         ssize_t reserve_len;
1108         int ret;
1109
1110         reserve_len = min_t(ssize_t,
1111                         chan->ops->packet_avail_size(chan->chan, chan->handle),
1112                         len);
1113         lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
1114                         sizeof(char), -1, chan->handle);
1115         ret = chan->ops->event_reserve(&ctx, 0);
1116         if (ret != 0) {
1117                 DBG("LTTng: event reservation failed");
1118                 assert(ret < 0);
1119                 reserve_len = ret;
1120                 goto end;
1121         }
1122         chan->ops->event_write(&ctx, str, reserve_len);
1123         chan->ops->event_commit(&ctx);
1124
1125 end:
1126         return reserve_len;
1127 }
1128
1129 int ustctl_channel_close_wait_fd(struct ustctl_consumer_channel *consumer_chan)
1130 {
1131         struct channel *chan;
1132         int ret;
1133
1134         chan = consumer_chan->chan->chan;
1135         ret = ring_buffer_channel_close_wait_fd(&chan->backend.config,
1136                         chan, chan->handle);
1137         if (!ret)
1138                 consumer_chan->wait_fd = -1;
1139         return ret;
1140 }
1141
1142 int ustctl_channel_close_wakeup_fd(struct ustctl_consumer_channel *consumer_chan)
1143 {
1144         struct channel *chan;
1145         int ret;
1146
1147         chan = consumer_chan->chan->chan;
1148         ret = ring_buffer_channel_close_wakeup_fd(&chan->backend.config,
1149                         chan, chan->handle);
1150         if (!ret)
1151                 consumer_chan->wakeup_fd = -1;
1152         return ret;
1153 }
1154
1155 int ustctl_stream_close_wait_fd(struct ustctl_consumer_stream *stream)
1156 {
1157         struct channel *chan;
1158
1159         chan = stream->chan->chan->chan;
1160         return ring_buffer_stream_close_wait_fd(&chan->backend.config,
1161                         chan, stream->handle, stream->cpu);
1162 }
1163
1164 int ustctl_stream_close_wakeup_fd(struct ustctl_consumer_stream *stream)
1165 {
1166         struct channel *chan;
1167
1168         chan = stream->chan->chan->chan;
1169         return ring_buffer_stream_close_wakeup_fd(&chan->backend.config,
1170                         chan, stream->handle, stream->cpu);
1171 }
1172
1173 struct ustctl_consumer_stream *
1174         ustctl_create_stream(struct ustctl_consumer_channel *channel,
1175                         int cpu)
1176 {
1177         struct ustctl_consumer_stream *stream;
1178         struct lttng_ust_shm_handle *handle;
1179         struct channel *chan;
1180         int shm_fd, wait_fd, wakeup_fd;
1181         uint64_t memory_map_size;
1182         struct lttng_ust_lib_ring_buffer *buf;
1183         int ret;
1184
1185         if (!channel)
1186                 return NULL;
1187         handle = channel->chan->handle;
1188         if (!handle)
1189                 return NULL;
1190
1191         chan = channel->chan->chan;
1192         buf = channel_get_ring_buffer(&chan->backend.config,
1193                 chan, cpu, handle, &shm_fd, &wait_fd,
1194                 &wakeup_fd, &memory_map_size);
1195         if (!buf)
1196                 return NULL;
1197         ret = lib_ring_buffer_open_read(buf, handle);
1198         if (ret)
1199                 return NULL;
1200
1201         stream = zmalloc(sizeof(*stream));
1202         if (!stream)
1203                 goto alloc_error;
1204         stream->handle = handle;
1205         stream->buf = buf;
1206         stream->chan = channel;
1207         stream->shm_fd = shm_fd;
1208         stream->wait_fd = wait_fd;
1209         stream->wakeup_fd = wakeup_fd;
1210         stream->memory_map_size = memory_map_size;
1211         stream->cpu = cpu;
1212         return stream;
1213
1214 alloc_error:
1215         return NULL;
1216 }
1217
1218 void ustctl_destroy_stream(struct ustctl_consumer_stream *stream)
1219 {
1220         struct lttng_ust_lib_ring_buffer *buf;
1221         struct ustctl_consumer_channel *consumer_chan;
1222
1223         assert(stream);
1224         buf = stream->buf;
1225         consumer_chan = stream->chan;
1226         (void) ustctl_stream_close_wait_fd(stream);
1227         (void) ustctl_stream_close_wakeup_fd(stream);
1228         lib_ring_buffer_release_read(buf, consumer_chan->chan->handle);
1229         free(stream);
1230 }
1231
1232 int ustctl_channel_get_wait_fd(struct ustctl_consumer_channel *chan)
1233 {
1234         if (!chan)
1235                 return -EINVAL;
1236         return shm_get_wait_fd(chan->chan->handle,
1237                 &chan->chan->handle->chan._ref);
1238 }
1239
1240 int ustctl_channel_get_wakeup_fd(struct ustctl_consumer_channel *chan)
1241 {
1242         if (!chan)
1243                 return -EINVAL;
1244         return shm_get_wakeup_fd(chan->chan->handle,
1245                 &chan->chan->handle->chan._ref);
1246 }
1247
1248 int ustctl_stream_get_wait_fd(struct ustctl_consumer_stream *stream)
1249 {
1250         struct lttng_ust_lib_ring_buffer *buf;
1251         struct ustctl_consumer_channel *consumer_chan;
1252
1253         if (!stream)
1254                 return -EINVAL;
1255         buf = stream->buf;
1256         consumer_chan = stream->chan;
1257         return shm_get_wait_fd(consumer_chan->chan->handle, &buf->self._ref);
1258 }
1259
1260 int ustctl_stream_get_wakeup_fd(struct ustctl_consumer_stream *stream)
1261 {
1262         struct lttng_ust_lib_ring_buffer *buf;
1263         struct ustctl_consumer_channel *consumer_chan;
1264
1265         if (!stream)
1266                 return -EINVAL;
1267         buf = stream->buf;
1268         consumer_chan = stream->chan;
1269         return shm_get_wakeup_fd(consumer_chan->chan->handle, &buf->self._ref);
1270 }
1271
1272 /* For mmap mode, readable without "get" operation */
1273
1274 void *ustctl_get_mmap_base(struct ustctl_consumer_stream *stream)
1275 {
1276         struct lttng_ust_lib_ring_buffer *buf;
1277         struct ustctl_consumer_channel *consumer_chan;
1278
1279         if (!stream)
1280                 return NULL;
1281         buf = stream->buf;
1282         consumer_chan = stream->chan;
1283         return shmp(consumer_chan->chan->handle, buf->backend.memory_map);
1284 }
1285
1286 /* returns the length to mmap. */
1287 int ustctl_get_mmap_len(struct ustctl_consumer_stream *stream,
1288                 unsigned long *len)
1289 {
1290         struct ustctl_consumer_channel *consumer_chan;
1291         unsigned long mmap_buf_len;
1292         struct channel *chan;
1293
1294         if (!stream)
1295                 return -EINVAL;
1296         consumer_chan = stream->chan;
1297         chan = consumer_chan->chan->chan;
1298         if (chan->backend.config.output != RING_BUFFER_MMAP)
1299                 return -EINVAL;
1300         mmap_buf_len = chan->backend.buf_size;
1301         if (chan->backend.extra_reader_sb)
1302                 mmap_buf_len += chan->backend.subbuf_size;
1303         if (mmap_buf_len > INT_MAX)
1304                 return -EFBIG;
1305         *len = mmap_buf_len;
1306         return 0;
1307 }
1308
1309 /* returns the maximum size for sub-buffers. */
1310 int ustctl_get_max_subbuf_size(struct ustctl_consumer_stream *stream,
1311                 unsigned long *len)
1312 {
1313         struct ustctl_consumer_channel *consumer_chan;
1314         struct channel *chan;
1315
1316         if (!stream)
1317                 return -EINVAL;
1318         consumer_chan = stream->chan;
1319         chan = consumer_chan->chan->chan;
1320         *len = chan->backend.subbuf_size;
1321         return 0;
1322 }
1323
1324 /*
1325  * For mmap mode, operate on the current packet (between get/put or
1326  * get_next/put_next).
1327  */
1328
1329 /* returns the offset of the subbuffer belonging to the mmap reader. */
1330 int ustctl_get_mmap_read_offset(struct ustctl_consumer_stream *stream,
1331                 unsigned long *off)
1332 {
1333         struct channel *chan;
1334         unsigned long sb_bindex;
1335         struct lttng_ust_lib_ring_buffer *buf;
1336         struct ustctl_consumer_channel *consumer_chan;
1337         struct lttng_ust_lib_ring_buffer_backend_pages_shmp *barray_idx;
1338         struct lttng_ust_lib_ring_buffer_backend_pages *pages;
1339
1340         if (!stream)
1341                 return -EINVAL;
1342         buf = stream->buf;
1343         consumer_chan = stream->chan;
1344         chan = consumer_chan->chan->chan;
1345         if (chan->backend.config.output != RING_BUFFER_MMAP)
1346                 return -EINVAL;
1347         sb_bindex = subbuffer_id_get_index(&chan->backend.config,
1348                                         buf->backend.buf_rsb.id);
1349         barray_idx = shmp_index(consumer_chan->chan->handle, buf->backend.array,
1350                         sb_bindex);
1351         if (!barray_idx)
1352                 return -EINVAL;
1353         pages = shmp(consumer_chan->chan->handle, barray_idx->shmp);
1354         if (!pages)
1355                 return -EINVAL;
1356         *off = pages->mmap_offset;
1357         return 0;
1358 }
1359
1360 /* returns the size of the current sub-buffer, without padding (for mmap). */
1361 int ustctl_get_subbuf_size(struct ustctl_consumer_stream *stream,
1362                 unsigned long *len)
1363 {
1364         struct ustctl_consumer_channel *consumer_chan;
1365         struct channel *chan;
1366         struct lttng_ust_lib_ring_buffer *buf;
1367
1368         if (!stream)
1369                 return -EINVAL;
1370
1371         buf = stream->buf;
1372         consumer_chan = stream->chan;
1373         chan = consumer_chan->chan->chan;
1374         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
1375                 consumer_chan->chan->handle);
1376         return 0;
1377 }
1378
1379 /* returns the size of the current sub-buffer, without padding (for mmap). */
1380 int ustctl_get_padded_subbuf_size(struct ustctl_consumer_stream *stream,
1381                 unsigned long *len)
1382 {
1383         struct ustctl_consumer_channel *consumer_chan;
1384         struct channel *chan;
1385         struct lttng_ust_lib_ring_buffer *buf;
1386
1387         if (!stream)
1388                 return -EINVAL;
1389         buf = stream->buf;
1390         consumer_chan = stream->chan;
1391         chan = consumer_chan->chan->chan;
1392         *len = lib_ring_buffer_get_read_data_size(&chan->backend.config, buf,
1393                 consumer_chan->chan->handle);
1394         *len = PAGE_ALIGN(*len);
1395         return 0;
1396 }
1397
1398 /* Get exclusive read access to the next sub-buffer that can be read. */
1399 int ustctl_get_next_subbuf(struct ustctl_consumer_stream *stream)
1400 {
1401         struct lttng_ust_lib_ring_buffer *buf;
1402         struct ustctl_consumer_channel *consumer_chan;
1403
1404         if (!stream)
1405                 return -EINVAL;
1406         buf = stream->buf;
1407         consumer_chan = stream->chan;
1408         return lib_ring_buffer_get_next_subbuf(buf,
1409                         consumer_chan->chan->handle);
1410 }
1411
1412
1413 /* Release exclusive sub-buffer access, move consumer forward. */
1414 int ustctl_put_next_subbuf(struct ustctl_consumer_stream *stream)
1415 {
1416         struct lttng_ust_lib_ring_buffer *buf;
1417         struct ustctl_consumer_channel *consumer_chan;
1418
1419         if (!stream)
1420                 return -EINVAL;
1421         buf = stream->buf;
1422         consumer_chan = stream->chan;
1423         lib_ring_buffer_put_next_subbuf(buf, consumer_chan->chan->handle);
1424         return 0;
1425 }
1426
1427 /* snapshot */
1428
1429 /* Get a snapshot of the current ring buffer producer and consumer positions */
1430 int ustctl_snapshot(struct ustctl_consumer_stream *stream)
1431 {
1432         struct lttng_ust_lib_ring_buffer *buf;
1433         struct ustctl_consumer_channel *consumer_chan;
1434
1435         if (!stream)
1436                 return -EINVAL;
1437         buf = stream->buf;
1438         consumer_chan = stream->chan;
1439         return lib_ring_buffer_snapshot(buf, &buf->cons_snapshot,
1440                         &buf->prod_snapshot, consumer_chan->chan->handle);
1441 }
1442
1443 /* Get the consumer position (iteration start) */
1444 int ustctl_snapshot_get_consumed(struct ustctl_consumer_stream *stream,
1445                 unsigned long *pos)
1446 {
1447         struct lttng_ust_lib_ring_buffer *buf;
1448
1449         if (!stream)
1450                 return -EINVAL;
1451         buf = stream->buf;
1452         *pos = buf->cons_snapshot;
1453         return 0;
1454 }
1455
1456 /* Get the producer position (iteration end) */
1457 int ustctl_snapshot_get_produced(struct ustctl_consumer_stream *stream,
1458                 unsigned long *pos)
1459 {
1460         struct lttng_ust_lib_ring_buffer *buf;
1461
1462         if (!stream)
1463                 return -EINVAL;
1464         buf = stream->buf;
1465         *pos = buf->prod_snapshot;
1466         return 0;
1467 }
1468
1469 /* Get exclusive read access to the specified sub-buffer position */
1470 int ustctl_get_subbuf(struct ustctl_consumer_stream *stream,
1471                 unsigned long *pos)
1472 {
1473         struct lttng_ust_lib_ring_buffer *buf;
1474         struct ustctl_consumer_channel *consumer_chan;
1475
1476         if (!stream)
1477                 return -EINVAL;
1478         buf = stream->buf;
1479         consumer_chan = stream->chan;
1480         return lib_ring_buffer_get_subbuf(buf, *pos,
1481                         consumer_chan->chan->handle);
1482 }
1483
1484 /* Release exclusive sub-buffer access */
1485 int ustctl_put_subbuf(struct ustctl_consumer_stream *stream)
1486 {
1487         struct lttng_ust_lib_ring_buffer *buf;
1488         struct ustctl_consumer_channel *consumer_chan;
1489
1490         if (!stream)
1491                 return -EINVAL;
1492         buf = stream->buf;
1493         consumer_chan = stream->chan;
1494         lib_ring_buffer_put_subbuf(buf, consumer_chan->chan->handle);
1495         return 0;
1496 }
1497
1498 void ustctl_flush_buffer(struct ustctl_consumer_stream *stream,
1499                 int producer_active)
1500 {
1501         struct lttng_ust_lib_ring_buffer *buf;
1502         struct ustctl_consumer_channel *consumer_chan;
1503
1504         assert(stream);
1505         buf = stream->buf;
1506         consumer_chan = stream->chan;
1507         lib_ring_buffer_switch_slow(buf,
1508                 producer_active ? SWITCH_ACTIVE : SWITCH_FLUSH,
1509                 consumer_chan->chan->handle);
1510 }
1511
1512 static
1513 struct lttng_ust_client_lib_ring_buffer_client_cb *get_client_cb(
1514                 struct lttng_ust_lib_ring_buffer *buf,
1515                 struct lttng_ust_shm_handle *handle)
1516 {
1517         struct channel *chan;
1518         const struct lttng_ust_lib_ring_buffer_config *config;
1519         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1520
1521         chan = shmp(handle, buf->backend.chan);
1522         if (!chan)
1523                 return NULL;
1524         config = &chan->backend.config;
1525         if (!config->cb_ptr)
1526                 return NULL;
1527         client_cb = caa_container_of(config->cb_ptr,
1528                         struct lttng_ust_client_lib_ring_buffer_client_cb,
1529                         parent);
1530         return client_cb;
1531 }
1532
1533 int ustctl_get_timestamp_begin(struct ustctl_consumer_stream *stream,
1534                 uint64_t *timestamp_begin)
1535 {
1536         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1537         struct lttng_ust_lib_ring_buffer *buf;
1538         struct lttng_ust_shm_handle *handle;
1539
1540         if (!stream || !timestamp_begin)
1541                 return -EINVAL;
1542         buf = stream->buf;
1543         handle = stream->chan->chan->handle;
1544         client_cb = get_client_cb(buf, handle);
1545         if (!client_cb)
1546                 return -ENOSYS;
1547         return client_cb->timestamp_begin(buf, handle, timestamp_begin);
1548 }
1549
1550 int ustctl_get_timestamp_end(struct ustctl_consumer_stream *stream,
1551         uint64_t *timestamp_end)
1552 {
1553         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1554         struct lttng_ust_lib_ring_buffer *buf;
1555         struct lttng_ust_shm_handle *handle;
1556
1557         if (!stream || !timestamp_end)
1558                 return -EINVAL;
1559         buf = stream->buf;
1560         handle = stream->chan->chan->handle;
1561         client_cb = get_client_cb(buf, handle);
1562         if (!client_cb)
1563                 return -ENOSYS;
1564         return client_cb->timestamp_end(buf, handle, timestamp_end);
1565 }
1566
1567 int ustctl_get_events_discarded(struct ustctl_consumer_stream *stream,
1568         uint64_t *events_discarded)
1569 {
1570         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1571         struct lttng_ust_lib_ring_buffer *buf;
1572         struct lttng_ust_shm_handle *handle;
1573
1574         if (!stream || !events_discarded)
1575                 return -EINVAL;
1576         buf = stream->buf;
1577         handle = stream->chan->chan->handle;
1578         client_cb = get_client_cb(buf, handle);
1579         if (!client_cb)
1580                 return -ENOSYS;
1581         return client_cb->events_discarded(buf, handle, events_discarded);
1582 }
1583
1584 int ustctl_get_content_size(struct ustctl_consumer_stream *stream,
1585         uint64_t *content_size)
1586 {
1587         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1588         struct lttng_ust_lib_ring_buffer *buf;
1589         struct lttng_ust_shm_handle *handle;
1590
1591         if (!stream || !content_size)
1592                 return -EINVAL;
1593         buf = stream->buf;
1594         handle = stream->chan->chan->handle;
1595         client_cb = get_client_cb(buf, handle);
1596         if (!client_cb)
1597                 return -ENOSYS;
1598         return client_cb->content_size(buf, handle, content_size);
1599 }
1600
1601 int ustctl_get_packet_size(struct ustctl_consumer_stream *stream,
1602         uint64_t *packet_size)
1603 {
1604         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1605         struct lttng_ust_lib_ring_buffer *buf;
1606         struct lttng_ust_shm_handle *handle;
1607
1608         if (!stream || !packet_size)
1609                 return -EINVAL;
1610         buf = stream->buf;
1611         handle = stream->chan->chan->handle;
1612         client_cb = get_client_cb(buf, handle);
1613         if (!client_cb)
1614                 return -ENOSYS;
1615         return client_cb->packet_size(buf, handle, packet_size);
1616 }
1617
1618 int ustctl_get_stream_id(struct ustctl_consumer_stream *stream,
1619                 uint64_t *stream_id)
1620 {
1621         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1622         struct lttng_ust_lib_ring_buffer *buf;
1623         struct lttng_ust_shm_handle *handle;
1624
1625         if (!stream || !stream_id)
1626                 return -EINVAL;
1627         buf = stream->buf;
1628         handle = stream->chan->chan->handle;
1629         client_cb = get_client_cb(buf, handle);
1630         if (!client_cb)
1631                 return -ENOSYS;
1632         return client_cb->stream_id(buf, handle, stream_id);
1633 }
1634
1635 int ustctl_get_current_timestamp(struct ustctl_consumer_stream *stream,
1636                 uint64_t *ts)
1637 {
1638         struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
1639         struct lttng_ust_lib_ring_buffer *buf;
1640         struct lttng_ust_shm_handle *handle;
1641
1642         if (!stream || !ts)
1643                 return -EINVAL;
1644         buf = stream->buf;
1645         handle = stream->chan->chan->handle;
1646         client_cb = get_client_cb(buf, handle);
1647         if (!client_cb || !client_cb->current_timestamp)
1648                 return -ENOSYS;
1649         return client_cb->current_timestamp(buf, handle, ts);
1650 }
1651
1652 #if defined(__x86_64__) || defined(__i386__)
1653
1654 int ustctl_has_perf_counters(void)
1655 {
1656         return 1;
1657 }
1658
1659 #else
1660
1661 int ustctl_has_perf_counters(void)
1662 {
1663         return 0;
1664 }
1665
1666 #endif
1667
1668 /*
1669  * Returns 0 on success, negative error value on error.
1670  */
1671 int ustctl_recv_reg_msg(int sock,
1672         enum ustctl_socket_type *type,
1673         uint32_t *major,
1674         uint32_t *minor,
1675         uint32_t *pid,
1676         uint32_t *ppid,
1677         uint32_t *uid,
1678         uint32_t *gid,
1679         uint32_t *bits_per_long,
1680         uint32_t *uint8_t_alignment,
1681         uint32_t *uint16_t_alignment,
1682         uint32_t *uint32_t_alignment,
1683         uint32_t *uint64_t_alignment,
1684         uint32_t *long_alignment,
1685         int *byte_order,
1686         char *name)
1687 {
1688         ssize_t len;
1689         struct ustctl_reg_msg reg_msg;
1690
1691         len = ustcomm_recv_unix_sock(sock, &reg_msg, sizeof(reg_msg));
1692         if (len > 0 && len != sizeof(reg_msg))
1693                 return -EIO;
1694         if (len == 0)
1695                 return -EPIPE;
1696         if (len < 0)
1697                 return len;
1698
1699         if (reg_msg.magic == LTTNG_UST_COMM_MAGIC) {
1700                 *byte_order = BYTE_ORDER == BIG_ENDIAN ?
1701                                 BIG_ENDIAN : LITTLE_ENDIAN;
1702         } else if (reg_msg.magic == bswap_32(LTTNG_UST_COMM_MAGIC)) {
1703                 *byte_order = BYTE_ORDER == BIG_ENDIAN ?
1704                                 LITTLE_ENDIAN : BIG_ENDIAN;
1705         } else {
1706                 return -LTTNG_UST_ERR_INVAL_MAGIC;
1707         }
1708         switch (reg_msg.socket_type) {
1709         case 0: *type = USTCTL_SOCKET_CMD;
1710                 break;
1711         case 1: *type = USTCTL_SOCKET_NOTIFY;
1712                 break;
1713         default:
1714                 return -LTTNG_UST_ERR_INVAL_SOCKET_TYPE;
1715         }
1716         *major = reg_msg.major;
1717         *minor = reg_msg.minor;
1718         *pid = reg_msg.pid;
1719         *ppid = reg_msg.ppid;
1720         *uid = reg_msg.uid;
1721         *gid = reg_msg.gid;
1722         *bits_per_long = reg_msg.bits_per_long;
1723         *uint8_t_alignment = reg_msg.uint8_t_alignment;
1724         *uint16_t_alignment = reg_msg.uint16_t_alignment;
1725         *uint32_t_alignment = reg_msg.uint32_t_alignment;
1726         *uint64_t_alignment = reg_msg.uint64_t_alignment;
1727         *long_alignment = reg_msg.long_alignment;
1728         memcpy(name, reg_msg.name, LTTNG_UST_ABI_PROCNAME_LEN);
1729         if (reg_msg.major != LTTNG_UST_ABI_MAJOR_VERSION) {
1730                 return -LTTNG_UST_ERR_UNSUP_MAJOR;
1731         }
1732
1733         return 0;
1734 }
1735
1736 int ustctl_recv_notify(int sock, enum ustctl_notify_cmd *notify_cmd)
1737 {
1738         struct ustcomm_notify_hdr header;
1739         ssize_t len;
1740
1741         len = ustcomm_recv_unix_sock(sock, &header, sizeof(header));
1742         if (len > 0 && len != sizeof(header))
1743                 return -EIO;
1744         if (len == 0)
1745                 return -EPIPE;
1746         if (len < 0)
1747                 return len;
1748         switch (header.notify_cmd) {
1749         case 0:
1750                 *notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
1751                 break;
1752         case 1:
1753                 *notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
1754                 break;
1755         default:
1756                 return -EINVAL;
1757         }
1758         return 0;
1759 }
1760
1761 /*
1762  * Returns 0 on success, negative error value on error.
1763  */
1764 int ustctl_recv_register_event(int sock,
1765         int *session_objd,
1766         int *channel_objd,
1767         char *event_name,
1768         int *loglevel,
1769         char **signature,
1770         size_t *nr_fields,
1771         struct ustctl_field **fields,
1772         char **model_emf_uri)
1773 {
1774         ssize_t len;
1775         struct ustcomm_notify_event_msg msg;
1776         size_t signature_len, fields_len, model_emf_uri_len;
1777         char *a_sign = NULL, *a_model_emf_uri = NULL;
1778         struct ustctl_field *a_fields = NULL;
1779
1780         len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
1781         if (len > 0 && len != sizeof(msg))
1782                 return -EIO;
1783         if (len == 0)
1784                 return -EPIPE;
1785         if (len < 0)
1786                 return len;
1787
1788         *session_objd = msg.session_objd;
1789         *channel_objd = msg.channel_objd;
1790         strncpy(event_name, msg.event_name, LTTNG_UST_SYM_NAME_LEN);
1791         event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
1792         *loglevel = msg.loglevel;
1793         signature_len = msg.signature_len;
1794         fields_len = msg.fields_len;
1795
1796         if (fields_len % sizeof(*a_fields) != 0) {
1797                 return -EINVAL;
1798         }
1799
1800         model_emf_uri_len = msg.model_emf_uri_len;
1801
1802         /* recv signature. contains at least \0. */
1803         a_sign = zmalloc(signature_len);
1804         if (!a_sign)
1805                 return -ENOMEM;
1806         len = ustcomm_recv_unix_sock(sock, a_sign, signature_len);
1807         if (len > 0 && len != signature_len) {
1808                 len = -EIO;
1809                 goto signature_error;
1810         }
1811         if (len == 0) {
1812                 len = -EPIPE;
1813                 goto signature_error;
1814         }
1815         if (len < 0) {
1816                 goto signature_error;
1817         }
1818         /* Enforce end of string */
1819         a_sign[signature_len - 1] = '\0';
1820
1821         /* recv fields */
1822         if (fields_len) {
1823                 a_fields = zmalloc(fields_len);
1824                 if (!a_fields) {
1825                         len = -ENOMEM;
1826                         goto signature_error;
1827                 }
1828                 len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
1829                 if (len > 0 && len != fields_len) {
1830                         len = -EIO;
1831                         goto fields_error;
1832                 }
1833                 if (len == 0) {
1834                         len = -EPIPE;
1835                         goto fields_error;
1836                 }
1837                 if (len < 0) {
1838                         goto fields_error;
1839                 }
1840         }
1841
1842         if (model_emf_uri_len) {
1843                 /* recv model_emf_uri_len */
1844                 a_model_emf_uri = zmalloc(model_emf_uri_len);
1845                 if (!a_model_emf_uri) {
1846                         len = -ENOMEM;
1847                         goto fields_error;
1848                 }
1849                 len = ustcomm_recv_unix_sock(sock, a_model_emf_uri,
1850                                 model_emf_uri_len);
1851                 if (len > 0 && len != model_emf_uri_len) {
1852                         len = -EIO;
1853                         goto model_error;
1854                 }
1855                 if (len == 0) {
1856                         len = -EPIPE;
1857                         goto model_error;
1858                 }
1859                 if (len < 0) {
1860                         goto model_error;
1861                 }
1862                 /* Enforce end of string */
1863                 a_model_emf_uri[model_emf_uri_len - 1] = '\0';
1864         }
1865
1866         *signature = a_sign;
1867         *nr_fields = fields_len / sizeof(*a_fields);
1868         *fields = a_fields;
1869         *model_emf_uri = a_model_emf_uri;
1870
1871         return 0;
1872
1873 model_error:
1874         free(a_model_emf_uri);
1875 fields_error:
1876         free(a_fields);
1877 signature_error:
1878         free(a_sign);
1879         return len;
1880 }
1881
1882 /*
1883  * Returns 0 on success, negative error value on error.
1884  */
1885 int ustctl_reply_register_event(int sock,
1886         uint32_t id,
1887         int ret_code)
1888 {
1889         ssize_t len;
1890         struct {
1891                 struct ustcomm_notify_hdr header;
1892                 struct ustcomm_notify_event_reply r;
1893         } reply;
1894
1895         memset(&reply, 0, sizeof(reply));
1896         reply.header.notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
1897         reply.r.ret_code = ret_code;
1898         reply.r.event_id = id;
1899         len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
1900         if (len > 0 && len != sizeof(reply))
1901                 return -EIO;
1902         if (len < 0)
1903                 return len;
1904         return 0;
1905 }
1906
1907 /*
1908  * Returns 0 on success, negative UST or system error value on error.
1909  */
1910 int ustctl_recv_register_channel(int sock,
1911         int *session_objd,              /* session descriptor (output) */
1912         int *channel_objd,              /* channel descriptor (output) */
1913         size_t *nr_fields,
1914         struct ustctl_field **fields)
1915 {
1916         ssize_t len;
1917         struct ustcomm_notify_channel_msg msg;
1918         size_t fields_len;
1919         struct ustctl_field *a_fields;
1920
1921         len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
1922         if (len > 0 && len != sizeof(msg))
1923                 return -EIO;
1924         if (len == 0)
1925                 return -EPIPE;
1926         if (len < 0)
1927                 return len;
1928
1929         *session_objd = msg.session_objd;
1930         *channel_objd = msg.channel_objd;
1931         fields_len = msg.ctx_fields_len;
1932
1933         if (fields_len % sizeof(*a_fields) != 0) {
1934                 return -EINVAL;
1935         }
1936
1937         /* recv fields */
1938         if (fields_len) {
1939                 a_fields = zmalloc(fields_len);
1940                 if (!a_fields) {
1941                         len = -ENOMEM;
1942                         goto alloc_error;
1943                 }
1944                 len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
1945                 if (len > 0 && len != fields_len) {
1946                         len = -EIO;
1947                         goto fields_error;
1948                 }
1949                 if (len == 0) {
1950                         len = -EPIPE;
1951                         goto fields_error;
1952                 }
1953                 if (len < 0) {
1954                         goto fields_error;
1955                 }
1956                 *fields = a_fields;
1957         } else {
1958                 *fields = NULL;
1959         }
1960         *nr_fields = fields_len / sizeof(*a_fields);
1961         return 0;
1962
1963 fields_error:
1964         free(a_fields);
1965 alloc_error:
1966         return len;
1967 }
1968
1969 /*
1970  * Returns 0 on success, negative error value on error.
1971  */
1972 int ustctl_reply_register_channel(int sock,
1973         uint32_t chan_id,
1974         enum ustctl_channel_header header_type,
1975         int ret_code)
1976 {
1977         ssize_t len;
1978         struct {
1979                 struct ustcomm_notify_hdr header;
1980                 struct ustcomm_notify_channel_reply r;
1981         } reply;
1982
1983         memset(&reply, 0, sizeof(reply));
1984         reply.header.notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
1985         reply.r.ret_code = ret_code;
1986         reply.r.chan_id = chan_id;
1987         switch (header_type) {
1988         case USTCTL_CHANNEL_HEADER_COMPACT:
1989                 reply.r.header_type = 1;
1990                 break;
1991         case USTCTL_CHANNEL_HEADER_LARGE:
1992                 reply.r.header_type = 2;
1993                 break;
1994         default:
1995                 reply.r.header_type = 0;
1996                 break;
1997         }
1998         len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
1999         if (len > 0 && len != sizeof(reply))
2000                 return -EIO;
2001         if (len < 0)
2002                 return len;
2003         return 0;
2004 }
2005
2006 static __attribute__((constructor))
2007 void ustctl_init(void)
2008 {
2009         init_usterr();
2010         lttng_ring_buffer_metadata_client_init();
2011         lttng_ring_buffer_client_overwrite_init();
2012         lttng_ring_buffer_client_overwrite_rt_init();
2013         lttng_ring_buffer_client_discard_init();
2014         lttng_ring_buffer_client_discard_rt_init();
2015         lib_ringbuffer_signal_init();
2016 }
2017
2018 static __attribute__((destructor))
2019 void ustctl_exit(void)
2020 {
2021         lttng_ring_buffer_client_discard_rt_exit();
2022         lttng_ring_buffer_client_discard_exit();
2023         lttng_ring_buffer_client_overwrite_rt_exit();
2024         lttng_ring_buffer_client_overwrite_exit();
2025         lttng_ring_buffer_metadata_client_exit();
2026 }