src/common/sessiond-comm/sessiond-comm.h

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *                      Julien Desfossez <julien.desfossez@polymtl.ca>
   4  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 /*
  21  * This header is meant for liblttng and libust internal use ONLY. These
  22  * declarations should NOT be considered stable API.
  23  */
  24
  25 #ifndef _LTTNG_SESSIOND_COMM_H
  26 #define _LTTNG_SESSIOND_COMM_H
  27
  28 #include <limits.h>
  29 #include <lttng/lttng.h>
  30 #include <lttng/snapshot-internal.h>
  31 #include <lttng/save-internal.h>
  32 #include <common/compat/socket.h>
  33 #include <common/uri.h>
  34 #include <common/defaults.h>
  35 #include <common/compat/uuid.h>
  36
  37 #include <arpa/inet.h>
  38 #include <netinet/in.h>
  39 #include <sys/un.h>
  40
  41 #include "inet.h"
  42 #include "inet6.h"
  43 #include <common/unix.h>
  44
  45 /* Queue size of listen(2) */
  46 #define LTTNG_SESSIOND_COMM_MAX_LISTEN 64
  47
  48 /* Maximum number of FDs that can be sent over a Unix socket */
  49 #define LTTCOMM_MAX_SEND_FDS           4
  50
  51 /*
  52  * Get the error code index from 0 since LTTCOMM_OK start at 1000
  53  */
  54 #define LTTCOMM_ERR_INDEX(code) (code - LTTCOMM_CONSUMERD_COMMAND_SOCK_READY)
  55
  56 enum lttcomm_sessiond_command {
  57         /* Tracer command */
  58         LTTNG_ADD_CONTEXT                   = 0,
  59         LTTNG_CALIBRATE                     = 1,
  60         LTTNG_DISABLE_CHANNEL               = 2,
  61         LTTNG_DISABLE_EVENT                 = 3,
  62         LTTNG_LIST_SYSCALLS                 = 4,
  63         LTTNG_ENABLE_CHANNEL                = 5,
  64         LTTNG_ENABLE_EVENT                  = 6,
  65         /* 7 */
  66         /* Session daemon command */
  67         LTTNG_CREATE_SESSION                = 8,
  68         LTTNG_DESTROY_SESSION               = 9,
  69         LTTNG_LIST_CHANNELS                 = 10,
  70         LTTNG_LIST_DOMAINS                  = 11,
  71         LTTNG_LIST_EVENTS                   = 12,
  72         LTTNG_LIST_SESSIONS                 = 13,
  73         LTTNG_LIST_TRACEPOINTS              = 14,
  74         LTTNG_REGISTER_CONSUMER             = 15,
  75         LTTNG_START_TRACE                   = 16,
  76         LTTNG_STOP_TRACE                    = 17,
  77         LTTNG_LIST_TRACEPOINT_FIELDS        = 18,
  78
  79         /* Consumer */
  80         LTTNG_DISABLE_CONSUMER              = 19,
  81         LTTNG_ENABLE_CONSUMER               = 20,
  82         LTTNG_SET_CONSUMER_URI              = 21,
  83         /* 22 */
  84         /* 23 */
  85         LTTNG_DATA_PENDING                  = 24,
  86         LTTNG_SNAPSHOT_ADD_OUTPUT           = 25,
  87         LTTNG_SNAPSHOT_DEL_OUTPUT           = 26,
  88         LTTNG_SNAPSHOT_LIST_OUTPUT          = 27,
  89         LTTNG_SNAPSHOT_RECORD               = 28,
  90         LTTNG_CREATE_SESSION_SNAPSHOT       = 29,
  91         LTTNG_CREATE_SESSION_LIVE           = 30,
  92         LTTNG_SAVE_SESSION                  = 31,
  93         LTTNG_TRACK_PID                     = 32,
  94         LTTNG_UNTRACK_PID                   = 33,
  95         LTTNG_LIST_TRACKER_PIDS             = 34,
  96         LTTNG_SET_SESSION_SHM_PATH          = 40,
  97         LTTNG_METADATA_REGENERATE           = 41,
  98 };
  99
 100 enum lttcomm_relayd_command {
 101         RELAYD_ADD_STREAM                   = 1,
 102         RELAYD_CREATE_SESSION               = 2,
 103         RELAYD_START_DATA                   = 3,
 104         RELAYD_UPDATE_SYNC_INFO             = 4,
 105         RELAYD_VERSION                      = 5,
 106         RELAYD_SEND_METADATA                = 6,
 107         RELAYD_CLOSE_STREAM                 = 7,
 108         RELAYD_DATA_PENDING                 = 8,
 109         RELAYD_QUIESCENT_CONTROL            = 9,
 110         RELAYD_BEGIN_DATA_PENDING           = 10,
 111         RELAYD_END_DATA_PENDING             = 11,
 112         RELAYD_ADD_INDEX                    = 12,
 113         RELAYD_SEND_INDEX                   = 13,
 114         RELAYD_CLOSE_INDEX                  = 14,
 115         /* Live-reading commands (2.4+). */
 116         RELAYD_LIST_SESSIONS                = 15,
 117         /* All streams of the channel have been sent to the relayd (2.4+). */
 118         RELAYD_STREAMS_SENT                 = 16,
 119         /* Ask the relay to reset the metadata trace file (2.8+) */
 120         RELAYD_RESET_METADATA               = 17,
 121 };
 122
 123 /*
 124  * lttcomm error code.
 125  */
 126 enum lttcomm_return_code {
 127         LTTCOMM_CONSUMERD_SUCCESS            = 0,   /* Everything went fine. */
 128         LTTCOMM_CONSUMERD_COMMAND_SOCK_READY = 1,   /* Command socket ready */
 129         LTTCOMM_CONSUMERD_SUCCESS_RECV_FD,          /* Success on receiving fds */
 130         LTTCOMM_CONSUMERD_ERROR_RECV_FD,            /* Error on receiving fds */
 131         LTTCOMM_CONSUMERD_ERROR_RECV_CMD,           /* Error on receiving command */
 132         LTTCOMM_CONSUMERD_POLL_ERROR,               /* Error in polling thread */
 133         LTTCOMM_CONSUMERD_POLL_NVAL,                /* Poll on closed fd */
 134         LTTCOMM_CONSUMERD_POLL_HUP,                 /* All fds have hungup */
 135         LTTCOMM_CONSUMERD_EXIT_SUCCESS,             /* Consumerd exiting normally */
 136         LTTCOMM_CONSUMERD_EXIT_FAILURE,             /* Consumerd exiting on error */
 137         LTTCOMM_CONSUMERD_OUTFD_ERROR,              /* Error opening the tracefile */
 138         LTTCOMM_CONSUMERD_SPLICE_EBADF,             /* EBADF from splice(2) */
 139         LTTCOMM_CONSUMERD_SPLICE_EINVAL,            /* EINVAL from splice(2) */
 140         LTTCOMM_CONSUMERD_SPLICE_ENOMEM,            /* ENOMEM from splice(2) */
 141         LTTCOMM_CONSUMERD_SPLICE_ESPIPE,            /* ESPIPE from splice(2) */
 142         LTTCOMM_CONSUMERD_ENOMEM,                   /* Consumer is out of memory */
 143         LTTCOMM_CONSUMERD_ERROR_METADATA,           /* Error with metadata. */
 144         LTTCOMM_CONSUMERD_FATAL,                    /* Fatal error. */
 145         LTTCOMM_CONSUMERD_RELAYD_FAIL,              /* Error on remote relayd */
 146         LTTCOMM_CONSUMERD_CHANNEL_FAIL,             /* Channel creation failed. */
 147         LTTCOMM_CONSUMERD_CHAN_NOT_FOUND,           /* Channel not found. */
 148
 149         /* MUST be last element */
 150         LTTCOMM_NR,                                             /* Last element */
 151 };
 152
 153 /* lttng socket protocol. */
 154 enum lttcomm_sock_proto {
 155         LTTCOMM_SOCK_UDP,
 156         LTTCOMM_SOCK_TCP,
 157 };
 158
 159 /*
 160  * Index in the net_families array below. Please keep in sync!
 161  */
 162 enum lttcomm_sock_domain {
 163         LTTCOMM_INET      = 0,
 164         LTTCOMM_INET6     = 1,
 165 };
 166
 167 enum lttcomm_metadata_command {
 168         LTTCOMM_METADATA_REQUEST = 1,
 169 };
 170
 171 /*
 172  * Commands sent from the consumerd to the sessiond to request if new metadata
 173  * is available. This message is used to find the per UID _or_ per PID registry
 174  * for the channel key. For per UID lookup, the triplet
 175  * bits_per_long/uid/session_id is used. On lookup failure, we search for the
 176  * per PID registry indexed by session id ignoring the other values.
 177  */
 178 struct lttcomm_metadata_request_msg {
 179         uint64_t session_id; /* Tracing session id */
 180         uint64_t session_id_per_pid; /* Tracing session id for per-pid */
 181         uint32_t bits_per_long; /* Consumer ABI */
 182         uint32_t uid;
 183         uint64_t key; /* Metadata channel key. */
 184 } LTTNG_PACKED;
 185
 186 struct lttcomm_sockaddr {
 187         enum lttcomm_sock_domain type;
 188         union {
 189                 struct sockaddr_in sin;
 190                 struct sockaddr_in6 sin6;
 191         } addr;
 192 } LTTNG_PACKED;
 193
 194 struct lttcomm_sock {
 195         int32_t fd;
 196         enum lttcomm_sock_proto proto;
 197         struct lttcomm_sockaddr sockaddr;
 198         const struct lttcomm_proto_ops *ops;
 199 } LTTNG_PACKED;
 200
 201 /*
 202  * Relayd sock. Adds the protocol version to use for the communications with
 203  * the relayd.
 204  */
 205 struct lttcomm_relayd_sock {
 206         struct lttcomm_sock sock;
 207         uint32_t major;
 208         uint32_t minor;
 209 } LTTNG_PACKED;
 210
 211 struct lttcomm_net_family {
 212         int family;
 213         int (*create) (struct lttcomm_sock *sock, int type, int proto);
 214 };
 215
 216 struct lttcomm_proto_ops {
 217         int (*bind) (struct lttcomm_sock *sock);
 218         int (*close) (struct lttcomm_sock *sock);
 219         int (*connect) (struct lttcomm_sock *sock);
 220         struct lttcomm_sock *(*accept) (struct lttcomm_sock *sock);
 221         int (*listen) (struct lttcomm_sock *sock, int backlog);
 222         ssize_t (*recvmsg) (struct lttcomm_sock *sock, void *buf, size_t len,
 223                         int flags);
 224         ssize_t (*sendmsg) (struct lttcomm_sock *sock, const void *buf,
 225                         size_t len, int flags);
 226 };
 227
 228 /*
 229  * Data structure received from lttng client to session daemon.
 230  */
 231 struct lttcomm_session_msg {
 232         uint32_t cmd_type;      /* enum lttcomm_sessiond_command */
 233         struct lttng_session session;
 234         struct lttng_domain domain;
 235         union {
 236                 /* Event data */
 237                 struct {
 238                         char channel_name[LTTNG_SYMBOL_NAME_LEN];
 239                         struct lttng_event event LTTNG_PACKED;
 240                         /* Length of following filter expression. */
 241                         uint32_t expression_len;
 242                         /* Length of following bytecode for filter. */
 243                         uint32_t bytecode_len;
 244                         /* exclusion data */
 245                         uint32_t exclusion_count;
 246                         /*
 247                          * After this structure, the following variable-length
 248                          * items are transmitted:
 249                          * - char exclusion_names[LTTNG_SYMBOL_NAME_LEN][exclusion_count]
 250                          * - unsigned char filter_expression[expression_len]
 251                          * - unsigned char filter_bytecode[bytecode_len]
 252                          */
 253                 } LTTNG_PACKED enable;
 254                 struct {
 255                         char channel_name[LTTNG_SYMBOL_NAME_LEN];
 256                         struct lttng_event event LTTNG_PACKED;
 257                         /* Length of following filter expression. */
 258                         uint32_t expression_len;
 259                         /* Length of following bytecode for filter. */
 260                         uint32_t bytecode_len;
 261                         /*
 262                          * After this structure, the following variable-length
 263                          * items are transmitted:
 264                          * - unsigned char filter_expression[expression_len]
 265                          * - unsigned char filter_bytecode[bytecode_len]
 266                          */
 267                 } LTTNG_PACKED disable;
 268                 /* Create channel */
 269                 struct {
 270                         struct lttng_channel chan LTTNG_PACKED;
 271                 } LTTNG_PACKED channel;
 272                 /* Context */
 273                 struct {
 274                         char channel_name[LTTNG_SYMBOL_NAME_LEN];
 275                         struct lttng_event_context ctx LTTNG_PACKED;
 276                         uint32_t provider_name_len;
 277                         uint32_t context_name_len;
 278                 } LTTNG_PACKED context;
 279                 /* Use by register_consumer */
 280                 struct {
 281                         char path[PATH_MAX];
 282                 } LTTNG_PACKED reg;
 283                 /* List */
 284                 struct {
 285                         char channel_name[LTTNG_SYMBOL_NAME_LEN];
 286                 } LTTNG_PACKED list;
 287                 struct lttng_calibrate calibrate;
 288                 /* Used by the set_consumer_url and used by create_session also call */
 289                 struct {
 290                         /* Number of lttng_uri following */
 291                         uint32_t size;
 292                 } LTTNG_PACKED uri;
 293                 struct {
 294                         struct lttng_snapshot_output output LTTNG_PACKED;
 295                 } LTTNG_PACKED snapshot_output;
 296                 struct {
 297                         uint32_t wait;
 298                         struct lttng_snapshot_output output LTTNG_PACKED;
 299                 } LTTNG_PACKED snapshot_record;
 300                 struct {
 301                         uint32_t nb_uri;
 302                         unsigned int timer_interval;    /* usec */
 303                 } LTTNG_PACKED session_live;
 304                 struct {
 305                         struct lttng_save_session_attr attr; /* struct already packed */
 306                 } LTTNG_PACKED save_session;
 307                 struct {
 308                         char shm_path[PATH_MAX];
 309                 } LTTNG_PACKED set_shm_path;
 310                 struct {
 311                         uint32_t pid;
 312                 } LTTNG_PACKED pid_tracker;
 313         } u;
 314 } LTTNG_PACKED;
 315
 316 #define LTTNG_FILTER_MAX_LEN    65536
 317
 318 /*
 319  * Filter bytecode data. The reloc table is located at the end of the
 320  * bytecode. It is made of tuples: (uint16_t, var. len. string). It
 321  * starts at reloc_table_offset.
 322  */
 323 #define LTTNG_FILTER_PADDING    32
 324 struct lttng_filter_bytecode {
 325         uint32_t len;   /* len of data */
 326         uint32_t reloc_table_offset;
 327         uint64_t seqnum;
 328         char padding[LTTNG_FILTER_PADDING];
 329         char data[0];
 330 } LTTNG_PACKED;
 331
 332 /*
 333  * Event exclusion data. At the end of the structure, there will actually
 334  * by zero or more names, where the actual number of names is given by
 335  * the 'count' item of the structure.
 336  */
 337 #define LTTNG_EVENT_EXCLUSION_PADDING   32
 338 struct lttng_event_exclusion {
 339         uint32_t count;
 340         char padding[LTTNG_EVENT_EXCLUSION_PADDING];
 341         char names[0][LTTNG_SYMBOL_NAME_LEN];
 342 } LTTNG_PACKED;
 343
 344 #define LTTNG_EVENT_EXCLUSION_NAME_AT(_exclusion, _i) \
 345         (&(_exclusion)->names[_i][0])
 346
 347 /*
 348  * Event command header.
 349  */
 350 struct lttcomm_event_command_header {
 351         /* Number of events */
 352         uint32_t nb_events;
 353 } LTTNG_PACKED;
 354
 355 /*
 356  * Event extended info header. This is the structure preceding each
 357  * extended info data.
 358  */
 359 struct lttcomm_event_extended_header {
 360         /*
 361          * Size of filter string immediately following this header.
 362          * This size includes the terminal null character.
 363          */
 364         uint32_t filter_len;
 365
 366         /*
 367          * Number of exclusion names, immediately following the filter
 368          * string. Each exclusion name has a fixed length of
 369          * LTTNG_SYMBOL_NAME_LEN bytes, including the terminal null
 370          * character.
 371          */
 372         uint32_t nb_exclusions;
 373 } LTTNG_PACKED;
 374
 375 /*
 376  * Channel extended info.
 377  */
 378 struct lttcomm_channel_extended {
 379         uint64_t discarded_events;
 380         uint64_t lost_packets;
 381 } LTTNG_PACKED;
 382
 383 /*
 384  * Data structure for the response from sessiond to the lttng client.
 385  */
 386 struct lttcomm_lttng_msg {
 387         uint32_t cmd_type;      /* enum lttcomm_sessiond_command */
 388         uint32_t ret_code;      /* enum lttcomm_return_code */
 389         uint32_t pid;           /* pid_t */
 390         uint32_t cmd_header_size;
 391         uint32_t data_size;
 392 } LTTNG_PACKED;
 393
 394 struct lttcomm_lttng_output_id {
 395         uint32_t id;
 396 } LTTNG_PACKED;
 397
 398 /*
 399  * lttcomm_consumer_msg is the message sent from sessiond to consumerd
 400  * to either add a channel, add a stream, update a stream, or stop
 401  * operation.
 402  */
 403 struct lttcomm_consumer_msg {
 404         uint32_t cmd_type;      /* enum consumerd_command */
 405         union {
 406                 struct {
 407                         uint64_t channel_key;
 408                         uint64_t session_id;
 409                         char pathname[PATH_MAX];
 410                         uint32_t uid;
 411                         uint32_t gid;
 412                         uint64_t relayd_id;
 413                         /* nb_init_streams is the number of streams open initially. */
 414                         uint32_t nb_init_streams;
 415                         char name[LTTNG_SYMBOL_NAME_LEN];
 416                         /* Use splice or mmap to consume this fd */
 417                         enum lttng_event_output output;
 418                         int type; /* Per cpu or metadata. */
 419                         uint64_t tracefile_size; /* bytes */
 420                         uint32_t tracefile_count; /* number of tracefiles */
 421                         /* If the channel's streams have to be monitored or not. */
 422                         uint32_t monitor;
 423                         /* timer to check the streams usage in live mode (usec). */
 424                         unsigned int live_timer_interval;
 425                 } LTTNG_PACKED channel; /* Only used by Kernel. */
 426                 struct {
 427                         uint64_t stream_key;
 428                         uint64_t channel_key;
 429                         int32_t cpu;    /* On which CPU this stream is assigned. */
 430                         /* Tells the consumer if the stream should be or not monitored. */
 431                         uint32_t no_monitor;
 432                 } LTTNG_PACKED stream;  /* Only used by Kernel. */
 433                 struct {
 434                         uint64_t net_index;
 435                         enum lttng_stream_type type;
 436                         /* Open socket to the relayd */
 437                         struct lttcomm_relayd_sock sock;
 438                         /* Tracing session id associated to the relayd. */
 439                         uint64_t session_id;
 440                         /* Relayd session id, only used with control socket. */
 441                         uint64_t relayd_session_id;
 442                 } LTTNG_PACKED relayd_sock;
 443                 struct {
 444                         uint64_t net_seq_idx;
 445                 } LTTNG_PACKED destroy_relayd;
 446                 struct {
 447                         uint64_t session_id;
 448                 } LTTNG_PACKED data_pending;
 449                 struct {
 450                         uint64_t subbuf_size;                   /* bytes */
 451                         uint64_t num_subbuf;                    /* power of 2 */
 452                         int32_t overwrite;                      /* 1: overwrite, 0: discard */
 453                         uint32_t switch_timer_interval;         /* usec */
 454                         uint32_t read_timer_interval;           /* usec */
 455                         unsigned int live_timer_interval;               /* usec */
 456                         int32_t output;                         /* splice, mmap */
 457                         int32_t type;                           /* metadata or per_cpu */
 458                         uint64_t session_id;                    /* Tracing session id */
 459                         char pathname[PATH_MAX];                /* Channel file path. */
 460                         char name[LTTNG_SYMBOL_NAME_LEN];       /* Channel name. */
 461                         uint32_t uid;                           /* User ID of the session */
 462                         uint32_t gid;                           /* Group ID ot the session */
 463                         uint64_t relayd_id;                     /* Relayd id if apply. */
 464                         uint64_t key;                           /* Unique channel key. */
 465                         unsigned char uuid[UUID_LEN];   /* uuid for ust tracer. */
 466                         uint32_t chan_id;                       /* Channel ID on the tracer side. */
 467                         uint64_t tracefile_size;        /* bytes */
 468                         uint32_t tracefile_count;       /* number of tracefiles */
 469                         uint64_t session_id_per_pid;    /* Per-pid session ID. */
 470                         /* Tells the consumer if the stream should be or not monitored. */
 471                         uint32_t monitor;
 472                         /*
 473                          * For UST per UID buffers, this is the application UID of the
 474                          * channel.  This can be different from the user UID requesting the
 475                          * channel creation and used for the rights on the stream file
 476                          * because the application can be in the tracing for instance.
 477                          */
 478                         uint32_t ust_app_uid;
 479                         char root_shm_path[PATH_MAX];
 480                         char shm_path[PATH_MAX];
 481                 } LTTNG_PACKED ask_channel;
 482                 struct {
 483                         uint64_t key;
 484                 } LTTNG_PACKED get_channel;
 485                 struct {
 486                         uint64_t key;
 487                 } LTTNG_PACKED destroy_channel;
 488                 struct {
 489                         uint64_t key;   /* Metadata channel key. */
 490                         uint64_t target_offset; /* Offset in the consumer */
 491                         uint64_t len;   /* Length of metadata to be received. */
 492                         uint64_t version; /* Version of the metadata. */
 493                 } LTTNG_PACKED push_metadata;
 494                 struct {
 495                         uint64_t key;   /* Metadata channel key. */
 496                 } LTTNG_PACKED close_metadata;
 497                 struct {
 498                         uint64_t key;   /* Metadata channel key. */
 499                 } LTTNG_PACKED setup_metadata;
 500                 struct {
 501                         uint64_t key;   /* Channel key. */
 502                 } LTTNG_PACKED flush_channel;
 503                 struct {
 504                         char pathname[PATH_MAX];
 505                         /* Indicate if the snapshot goes on the relayd or locally. */
 506                         uint32_t use_relayd;
 507                         uint32_t metadata;              /* This a metadata snapshot. */
 508                         uint64_t relayd_id;             /* Relayd id if apply. */
 509                         uint64_t key;
 510                         uint64_t nb_packets_per_stream;
 511                 } LTTNG_PACKED snapshot_channel;
 512                 struct {
 513                         uint64_t channel_key;
 514                         uint64_t net_seq_idx;
 515                 } LTTNG_PACKED sent_streams;
 516                 struct {
 517                         uint64_t session_id;
 518                         uint64_t channel_key;
 519                 } LTTNG_PACKED discarded_events;
 520                 struct {
 521                         uint64_t session_id;
 522                         uint64_t channel_key;
 523                 } LTTNG_PACKED lost_packets;
 524                 struct {
 525                         uint64_t session_id;
 526                 } LTTNG_PACKED metadata_regenerate;
 527         } u;
 528 } LTTNG_PACKED;
 529
 530 /*
 531  * Status message returned to the sessiond after a received command.
 532  */
 533 struct lttcomm_consumer_status_msg {
 534         enum lttcomm_return_code ret_code;
 535 } LTTNG_PACKED;
 536
 537 struct lttcomm_consumer_status_channel {
 538         enum lttcomm_return_code ret_code;
 539         uint64_t key;
 540         unsigned int stream_count;
 541 } LTTNG_PACKED;
 542
 543 #ifdef HAVE_LIBLTTNG_UST_CTL
 544
 545 #include <lttng/ust-abi.h>
 546
 547 /*
 548  * Data structure for the commands sent from sessiond to UST.
 549  */
 550 struct lttcomm_ust_msg {
 551         uint32_t handle;
 552         uint32_t cmd;
 553         union {
 554                 struct lttng_ust_channel channel;
 555                 struct lttng_ust_stream stream;
 556                 struct lttng_ust_event event;
 557                 struct lttng_ust_context context;
 558                 struct lttng_ust_tracer_version version;
 559         } u;
 560 } LTTNG_PACKED;
 561
 562 /*
 563  * Data structure for the response from UST to the session daemon.
 564  * cmd_type is sent back in the reply for validation.
 565  */
 566 struct lttcomm_ust_reply {
 567         uint32_t handle;
 568         uint32_t cmd;
 569         uint32_t ret_code;      /* enum lttcomm_return_code */
 570         uint32_t ret_val;       /* return value */
 571         union {
 572                 struct {
 573                         uint64_t memory_map_size;
 574                 } LTTNG_PACKED channel;
 575                 struct {
 576                         uint64_t memory_map_size;
 577                 } LTTNG_PACKED stream;
 578                 struct lttng_ust_tracer_version version;
 579         } u;
 580 } LTTNG_PACKED;
 581
 582 #endif /* HAVE_LIBLTTNG_UST_CTL */
 583
 584 extern const char *lttcomm_get_readable_code(enum lttcomm_return_code code);
 585
 586 extern int lttcomm_init_inet_sockaddr(struct lttcomm_sockaddr *sockaddr,
 587                 const char *ip, unsigned int port);
 588 extern int lttcomm_init_inet6_sockaddr(struct lttcomm_sockaddr *sockaddr,
 589                 const char *ip, unsigned int port);
 590
 591 extern struct lttcomm_sock *lttcomm_alloc_sock(enum lttcomm_sock_proto proto);
 592 extern int lttcomm_create_sock(struct lttcomm_sock *sock);
 593 extern struct lttcomm_sock *lttcomm_alloc_sock_from_uri(struct lttng_uri *uri);
 594 extern void lttcomm_destroy_sock(struct lttcomm_sock *sock);
 595 extern struct lttcomm_sock *lttcomm_alloc_copy_sock(struct lttcomm_sock *src);
 596 extern void lttcomm_copy_sock(struct lttcomm_sock *dst,
 597                 struct lttcomm_sock *src);
 598
 599 /* Relayd socket object. */
 600 extern struct lttcomm_relayd_sock *lttcomm_alloc_relayd_sock(
 601                 struct lttng_uri *uri, uint32_t major, uint32_t minor);
 602
 603 extern int lttcomm_setsockopt_rcv_timeout(int sock, unsigned int msec);
 604 extern int lttcomm_setsockopt_snd_timeout(int sock, unsigned int msec);
 605
 606 extern void lttcomm_init(void);
 607 /* Get network timeout, in milliseconds */
 608 extern unsigned long lttcomm_get_network_timeout(void);
 609
 610 #endif  /* _LTTNG_SESSIOND_COMM_H */