src/common/mi-lttng.h

   1 /*
   2  * Copyright (C) 2014 - Jonathan Rajotte <jonathan.r.julien@gmail.com>
   3  *                    - Olivier Cotte <olivier.cotte@polymtl.ca>
   4  * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License, version 2 only, as
   8  * 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 with
  16  * this program; if not, write to the Free Software Foundation, Inc., 51
  17  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #ifndef _MI_LTTNG_H
  21 #define _MI_LTTNG_H
  22
  23 #include <stdint.h>
  24
  25 #include <common/error.h>
  26 #include <common/macros.h>
  27 #include <common/config/session-config.h>
  28 #include <lttng/lttng.h>
  29
  30 /* Don't want to reference snapshot-internal.h here */
  31 struct lttng_snapshot_output;
  32
  33 /* Instance of a machine interface writer. */
  34 struct mi_writer {
  35         struct config_writer *writer;
  36         enum lttng_mi_output_type type;
  37 };
  38
  39 /*
  40  * Version information for the machine interface.
  41  */
  42 struct mi_lttng_version {
  43         char version[LTTNG_NAME_MAX]; /* Version number of package */
  44         uint32_t version_major; /* LTTng-Tools major version number */
  45         uint32_t version_minor; /* LTTng-Tools minor version number */
  46         uint32_t version_patchlevel; /* LTTng-Tools patchlevel version number */
  47         char version_commit[LTTNG_NAME_MAX]; /* Commit hash of the current version */
  48         char version_name[LTTNG_NAME_MAX];
  49         char package_url[LTTNG_NAME_MAX]; /* Define to the home page for this package. */
  50 };
  51
  52 /* Strings related to command */
  53 extern const char * const mi_lttng_element_command;
  54 extern const char * const mi_lttng_element_command_action;
  55 extern const char * const mi_lttng_element_command_add_context;
  56 extern const char * const mi_lttng_element_command_create;
  57 extern const char * const mi_lttng_element_command_destroy;
  58 extern const char * const mi_lttng_element_command_disable_channel;
  59 extern const char * const mi_lttng_element_command_disable_event;
  60 extern const char * const mi_lttng_element_command_enable_channels;
  61 extern const char * const mi_lttng_element_command_enable_event;
  62 extern const char * const mi_lttng_element_command_list;
  63 extern const char * const mi_lttng_element_command_load;
  64 extern const char * const mi_lttng_element_command_metadata;
  65 extern const char * const mi_lttng_element_command_metadata_action;
  66 extern const char * const mi_lttng_element_command_regenerate;
  67 extern const char * const mi_lttng_element_command_regenerate_action;
  68 extern const char * const mi_lttng_element_command_name;
  69 extern const char * const mi_lttng_element_command_output;
  70 extern const char * const mi_lttng_element_command_save;
  71 extern const char * const mi_lttng_element_command_set_session;
  72 extern const char * const mi_lttng_element_command_snapshot;
  73 extern const char * const mi_lttng_element_command_snapshot_add;
  74 extern const char * const mi_lttng_element_command_snapshot_del;
  75 extern const char * const mi_lttng_element_command_snapshot_list;
  76 extern const char * const mi_lttng_element_command_snapshot_record;
  77 extern const char * const mi_lttng_element_command_start;
  78 extern const char * const mi_lttng_element_command_stop;
  79 extern const char * const mi_lttng_element_command_success;
  80 extern const char * const mi_lttng_element_command_track;
  81 extern const char * const mi_lttng_element_command_untrack;
  82 extern const char * const mi_lttng_element_command_version;
  83
  84 /* Strings related to version command */
  85 extern const char * const mi_lttng_element_version;
  86 extern const char * const mi_lttng_element_version_commit;
  87 extern const char * const mi_lttng_element_version_description;
  88 extern const char * const mi_lttng_element_version_license;
  89 extern const char * const mi_lttng_element_version_major;
  90 extern const char * const mi_lttng_element_version_minor;
  91 extern const char * const mi_lttng_element_version_patch_level;
  92 extern const char * const mi_lttng_element_version_str;
  93 extern const char * const mi_lttng_element_version_web;
  94
  95 /* String related to a lttng_event_field */
  96 extern const char * const mi_lttng_element_event_field;
  97 extern const char * const mi_lttng_element_event_fields;
  98
  99 /* String related to lttng_event_perf_counter_ctx */
 100 extern const char * const mi_lttng_element_perf_counter_context;
 101
 102 /* Strings related to pid */
 103 extern const char * const mi_lttng_element_pid_id;
 104
 105 /* Strings related to save command */
 106 extern const char * const mi_lttng_element_save;
 107
 108 /* Strings related to load command */
 109 extern const char * const mi_lttng_element_load;
 110
 111 /* General element of mi_lttng */
 112 extern const char * const mi_lttng_element_empty;
 113 extern const char * const mi_lttng_element_id;
 114 extern const char * const mi_lttng_element_nowrite;
 115 extern const char * const mi_lttng_element_success;
 116 extern const char * const mi_lttng_element_type_enum;
 117 extern const char * const mi_lttng_element_type_float;
 118 extern const char * const mi_lttng_element_type_integer;
 119 extern const char * const mi_lttng_element_type_other;
 120 extern const char * const mi_lttng_element_type_string;
 121
 122 /* String related to loglevel */
 123 extern const char * const mi_lttng_loglevel_str_alert;
 124 extern const char * const mi_lttng_loglevel_str_crit;
 125 extern const char * const mi_lttng_loglevel_str_debug;
 126 extern const char * const mi_lttng_loglevel_str_debug_function;
 127 extern const char * const mi_lttng_loglevel_str_debug_line;
 128 extern const char * const mi_lttng_loglevel_str_debug_module;
 129 extern const char * const mi_lttng_loglevel_str_debug_process;
 130 extern const char * const mi_lttng_loglevel_str_debug_program;
 131 extern const char * const mi_lttng_loglevel_str_debug_system;
 132 extern const char * const mi_lttng_loglevel_str_debug_unit;
 133 extern const char * const mi_lttng_loglevel_str_emerg;
 134 extern const char * const mi_lttng_loglevel_str_err;
 135 extern const char * const mi_lttng_loglevel_str_info;
 136 extern const char * const mi_lttng_loglevel_str_notice;
 137 extern const char * const mi_lttng_loglevel_str_unknown;
 138 extern const char * const mi_lttng_loglevel_str_warning;
 139
 140 /* String related to loglevel JUL */
 141 extern const char * const mi_lttng_loglevel_str_jul_all;
 142 extern const char * const mi_lttng_loglevel_str_jul_config;
 143 extern const char * const mi_lttng_loglevel_str_jul_fine;
 144 extern const char * const mi_lttng_loglevel_str_jul_finer;
 145 extern const char * const mi_lttng_loglevel_str_jul_finest;
 146 extern const char * const mi_lttng_loglevel_str_jul_info;
 147 extern const char * const mi_lttng_loglevel_str_jul_off;
 148 extern const char * const mi_lttng_loglevel_str_jul_severe;
 149 extern const char * const mi_lttng_loglevel_str_jul_warning;
 150
 151 /* String related to loglevel Log4j */
 152 extern const char * const mi_lttng_loglevel_str_log4j_off;
 153 extern const char * const mi_lttng_loglevel_str_log4j_fatal;
 154 extern const char * const mi_lttng_loglevel_str_log4j_error;
 155 extern const char * const mi_lttng_loglevel_str_log4j_warn;
 156 extern const char * const mi_lttng_loglevel_str_log4j_info;
 157 extern const char * const mi_lttng_loglevel_str_log4j_debug;
 158 extern const char * const mi_lttng_loglevel_str_log4j_trace;
 159 extern const char * const mi_lttng_loglevel_str_log4j_all;
 160
 161 /* String related to loglevel Python */
 162 extern const char * const mi_lttng_loglevel_str_python_critical;
 163 extern const char * const mi_lttng_loglevel_str_python_error;
 164 extern const char * const mi_lttng_loglevel_str_python_warning;
 165 extern const char * const mi_lttng_loglevel_str_python_info;
 166 extern const char * const mi_lttng_loglevel_str_python_debug;
 167 extern const char * const mi_lttng_loglevel_str_python_notset;
 168
 169 /* String related to loglevel type */
 170 extern const char * const mi_lttng_loglevel_type_all;
 171 extern const char * const mi_lttng_loglevel_type_range;
 172 extern const char * const mi_lttng_loglevel_type_single;
 173 extern const char * const mi_lttng_loglevel_type_unknown;
 174
 175 /* String related to a lttng_snapshot */
 176 extern const char * const mi_lttng_element_snapshot_ctrl_url;
 177 extern const char * const mi_lttng_element_snapshot_data_url;
 178 extern const char * const mi_lttng_element_snapshot_max_size;
 179 extern const char * const mi_lttng_element_snapshot_n_ptr;
 180 extern const char * const mi_lttng_element_snapshot_session_name;
 181 extern const char * const mi_lttng_element_snapshots;
 182
 183 /* String related to track/untrack command */
 184 const char * const mi_lttng_element_track_untrack_all_wildcard;
 185
 186 /* Utility string function  */
 187 const char *mi_lttng_loglevel_string(int value, enum lttng_domain_type domain);
 188 const char *mi_lttng_logleveltype_string(enum lttng_loglevel_type value);
 189 const char *mi_lttng_eventfieldtype_string(enum lttng_event_field_type value);
 190 const char *mi_lttng_domaintype_string(enum lttng_domain_type value);
 191 const char *mi_lttng_buffertype_string(enum lttng_buffer_type value);
 192
 193 /*
 194  * Create an instance of a machine interface writer.
 195  *
 196  * fd_output File to which the XML content must be written. The file will be
 197  * closed once the mi_writer has been destroyed.
 198  *
 199  * Returns an instance of a machine interface writer on success, NULL on
 200  * error.
 201  */
 202 struct mi_writer *mi_lttng_writer_create(int fd_output, int mi_output_type);
 203
 204 /*
 205  * Destroy an instance of a machine interface writer.
 206  *
 207  * writer An instance of a machine interface writer.
 208  *
 209  * Returns zero if the XML document could be closed cleanly. Negative values
 210  * indicate an error.
 211  */
 212 int mi_lttng_writer_destroy(struct mi_writer *writer);
 213
 214 /*
 215  * Open a command tag and add it's name node.
 216  *
 217  * writer An instance of a machine interface writer.
 218  * command The command name.
 219  *
 220  * Returns zero if the XML document could be closed cleanly.
 221  * Negative values indicate an error.
 222  */
 223 int mi_lttng_writer_command_open(struct mi_writer *writer, const char *command);
 224
 225 /*
 226  * Close a command tag.
 227  *
 228  * writer An instance of a machine interface writer.
 229  *
 230  * Returns zero if the XML document could be closed cleanly.
 231  * Negative values indicate an error.
 232  */
 233 int mi_lttng_writer_command_close(struct mi_writer *writer);
 234
 235 /*
 236  * Open an element tag.
 237  *
 238  * writer An instance of a machine interface writer.
 239  * element_name Element tag name.
 240  *
 241  * Returns zero if the XML document could be closed cleanly.
 242  * Negative values indicate an error.
 243  */
 244 int mi_lttng_writer_open_element(struct mi_writer *writer,
 245                 const char *element_name);
 246
 247 /*
 248  * Close the current element tag.
 249  *
 250  * writer An instance of a machine interface writer.
 251  *
 252  * Returns zero if the XML document could be closed cleanly.
 253  * Negative values indicate an error.
 254  */
 255 int mi_lttng_writer_close_element(struct mi_writer *writer);
 256
 257 /*
 258  * Close multiple element.
 259  *
 260  * writer An instance of a machine interface writer.
 261  * nb_element Number of elements.
 262  *
 263  * Returns zero if the XML document could be closed cleanly.
 264  * Negative values indicate an error.
 265  */
 266 int mi_lttng_close_multi_element(struct mi_writer *writer,
 267                 unsigned int nb_element);
 268
 269 /*
 270  * Write an element of type unsigned int.
 271  *
 272  * writer An instance of a machine interface writer.
 273  * element_name Element name.
 274  * value Unsigned int value of the element
 275  *
 276  * Returns zero if the element's value could be written.
 277  * Negative values indicate an error.
 278  */
 279 int mi_lttng_writer_write_element_unsigned_int(struct mi_writer *writer,
 280                 const char *element_name, uint64_t value);
 281
 282 /*
 283  * Write an element of type signed int.
 284  *
 285  * writer An instance of a machine interface writer.
 286  * element_name Element name.
 287  * value Signed int value of the element.
 288  *
 289  * Returns zero if the element's value could be written.
 290  * Negative values indicate an error.
 291  */
 292 int mi_lttng_writer_write_element_signed_int(struct mi_writer *writer,
 293                 const char *element_name, int64_t value);
 294
 295 /*
 296  * Write an element of type boolean.
 297  *
 298  * writer An instance of a machine interface writer.
 299  * element_name Element name.
 300  * value Boolean value of the element.
 301  *
 302  * Returns zero if the element's value could be written.
 303  * Negative values indicate an error.
 304  */
 305 int mi_lttng_writer_write_element_bool(struct mi_writer *writer,
 306                 const char *element_name, int value);
 307
 308 /*
 309  * Write an element of type string.
 310  *
 311  * writer An instance of a machine interface writer.
 312  * element_name Element name.
 313  * value String value of the element.
 314  *
 315  * Returns zero if the element's value could be written.
 316  * Negative values indicate an error.
 317  */
 318 int mi_lttng_writer_write_element_string(struct mi_writer *writer,
 319                 const char *element_name, const char *value);
 320
 321 /*
 322  * Machine interface of struct version.
 323  *
 324  * writer An instance of a machine interface writer.
 325  * version Version struct.
 326  * lttng_description String value of the version description.
 327  * lttng_license String value of the version license.
 328  *
 329  * Returns zero if the element's value could be written.
 330  * Negative values indicate an error.
 331  */
 332 int mi_lttng_version(struct mi_writer *writer, struct mi_lttng_version *version,
 333                 const char *lttng_description, const char *lttng_license);
 334
 335 /*
 336  * Machine interface: open a sessions element.
 337  *
 338  * writer An instance of a machine interface writer.
 339  *
 340  * Returns zero if the element's value could be written.
 341  * Negative values indicate an error.
 342  */
 343 int mi_lttng_sessions_open(struct mi_writer *writer);
 344
 345 /*
 346  * Machine interface of struct session.
 347  *
 348  * writer An instance of a machine interface writer.
 349  * session An instance of a session.
 350  * is_open Defines whether or not the session element shall be closed.
 351  *         This should be used carefully and the client
 352  *         must close the session element.
 353  *         Use case: nested additional information on a session
 354  *                  ex: domain,channel event.
 355  *
 356  * Returns zero if the element's value could be written.
 357  * Negative values indicate an error.
 358  */
 359 int mi_lttng_session(struct mi_writer *writer,
 360                 struct lttng_session *session, int is_open);
 361
 362 /*
 363  * Machine interface: open a domains element.
 364  *
 365  * writer An instance of a machine interface writer.
 366  *
 367  * Returns zero if the element's value could be written.
 368  * Negative values indicate an error.
 369  */
 370 int mi_lttng_domains_open(struct mi_writer *writer);
 371
 372 /*
 373  * Machine interface of struct domain.
 374  *
 375  * writer An instance of a machine interface writer.
 376  * domain An instance of a domain.
 377  *
 378  * is_open Defines whether or not the session element shall be closed.
 379  *         This should be used carefully and the client
 380  *         must close the domain element.
 381  *         Use case: nested addition information on a domain
 382  *                  ex: channel event.
 383  *
 384  * Returns zero if the element's value could be written.
 385  * Negative values indicate an error.
 386  */
 387 int mi_lttng_domain(struct mi_writer *writer,
 388                 struct lttng_domain *domain, int is_open);
 389
 390 /*
 391  * Machine interface: open a channels element.
 392  *
 393  * writer An instance of a machine interface writer.
 394  *
 395  * Returns zero if the element's value could be written.
 396  * Negative values indicate an error.
 397  */
 398 int mi_lttng_channels_open(struct mi_writer *writer);
 399
 400 /*
 401  * Machine interface of struct channel.
 402  *
 403  * writer An instance of a machine interface writer.
 404  * channel An instance of a channel.
 405  *
 406  * is_open Defines whether or not the session element shall be closed.
 407  *         This should be used carefully and the client
 408  *         must close the channel element.
 409  *         Use case: nested addition information on a channel.
 410  *                  ex: channel event.
 411  *
 412  * Returns zero if the element's value could be written.
 413  * Negative values indicate an error.
 414  */
 415 int mi_lttng_channel(struct mi_writer *writer,
 416                 struct lttng_channel *channel, int is_open);
 417
 418 /*
 419  * Machine interface of struct channel_attr.
 420  *
 421  * writer An instance of a machine interface writer.
 422  * attr An instance of a channel_attr struct.
 423  *
 424  * Returns zero if the element's value could be written.
 425  * Negative values indicate an error.
 426  */
 427 int mi_lttng_channel_attr(struct mi_writer *writer,
 428                 struct lttng_channel_attr *attr);
 429
 430 /*
 431 * Machine interface for event common attributes.
 432 *
 433 * writer An instance of a mi writer.
 434 * event single trace event.
 435 *
 436 * The common attribute are:
 437 * - mi event element
 438 * - event name
 439 * - event type
 440 * - enabled tag
 441 * - event filter
 442 *
 443 * Returns zero if the element's value could be written.
 444 * Negative values indicate an error.
 445 */
 446 int mi_lttng_event_common_attributes(struct mi_writer *writer,
 447                 struct lttng_event *event);
 448
 449 /*
 450  * Machine interface for kernel tracepoint event with a loglevel.
 451  *
 452  * writer An instance of a mi writer.
 453  * event single trace event.
 454  * domain Event's domain
 455  *
 456  * Returns zero if the element's value could be written.
 457  * Negative values indicate an error.
 458  */
 459 int mi_lttng_event_tracepoint_loglevel(struct mi_writer *writer,
 460                 struct lttng_event *event, enum lttng_domain_type domain);
 461
 462 /*
 463  * Machine interface for kernel tracepoint event with no loglevel.
 464  *
 465  * writer An instance of a mi writer.
 466  * event single trace event.
 467  *
 468  * Returns zero if the element's value could be written.
 469  * Negative values indicate an error.
 470  */
 471 int mi_lttng_event_tracepoint_no_loglevel(struct mi_writer *writer,
 472                 struct lttng_event *event);
 473
 474 /*
 475  * Machine interface for kernel function and probe event.
 476  *
 477  * writer An instance of a mi writer.
 478  * event single trace event.
 479  *
 480  * Returns zero if the element's value could be written.
 481  * Negative values indicate an error.
 482  */
 483 int mi_lttng_event_function_probe(struct mi_writer *writer,
 484                 struct lttng_event *event);
 485
 486 /*
 487  * Machine interface for kernel function entry event.
 488  *
 489  * writer An instance of a mi writer.
 490  * event single trace event.
 491  *
 492  * Returns zero if the element's value could be written.
 493  * Negative values indicate an error.
 494  */
 495 int mi_lttng_event_function_entry(struct mi_writer *writer,
 496                 struct lttng_event *event);
 497
 498 /*
 499  * Machine interface: open an events element.
 500  *
 501  * writer An instance of a machine interface writer.
 502  *
 503  * Returns zero if the element's value could be written.
 504  * Negative values indicate an error.
 505  */
 506 int mi_lttng_events_open(struct mi_writer *writer);
 507
 508 /*
 509  * Machine interface for printing an event.
 510  * The trace event type currently supported are:
 511  *  TRACEPOINT,
 512  *  PROBE,
 513  *  FUNCTION,
 514  *  FUNCTION_ENTRY,
 515  *  SYSCALL
 516  *
 517  * writer An instance of a mi writer.
 518  * event single trace event.
 519  * is_open Defines whether or not the session element shall be closed.
 520  *         This should be used carefully and the client
 521  *         must close the event element.
 522  *         Use case: nested additional information
 523  * domain Event's domain
 524  *
 525  * Returns zero if the element's value could be written.
 526  * Negative values indicate an error.
 527  */
 528 int mi_lttng_event(struct mi_writer *writer, struct lttng_event *event,
 529                 int is_open, enum lttng_domain_type domain);
 530
 531 /*
 532  * Machine interface for struct lttng_event_field.
 533  *
 534  * writer An instance of a mi writer.
 535  * field An event_field instance.
 536  *
 537  * Returns zero if the element's value could be written.
 538  * Negative values indicate an error.
 539  */
 540 int mi_lttng_event_field(struct mi_writer *writer,
 541                 struct lttng_event_field *field);
 542
 543 /*
 544  * Machine interface: open a event_fields element.
 545  *
 546  * writer An instance of a machine interface writer.
 547  *
 548  * Returns zero if the element have be written.
 549  * Negative values indicate an error.
 550  */
 551 int mi_lttng_event_fields_open(struct mi_writer *writer);
 552
 553 /*
 554  * Machine interface: open a trackers element.
 555  *
 556  * writer An instance of a machine interface writer.
 557  *
 558  * Returns zero if the element's value could be written.
 559  * Negative values indicate an error.
 560  */
 561 int mi_lttng_trackers_open(struct mi_writer *writer);
 562
 563 /*
 564  * Machine interface: open a pid_tracker element.
 565  *
 566  * writer An instance of a machine interface writer.
 567  *
 568  * Returns zero if the element's value could be written.
 569  * Negative values indicate an error.
 570  *
 571  * Note: A targets element is also opened for each tracker definition
 572  */
 573 int mi_lttng_pid_tracker_open(struct mi_writer *writer);
 574
 575 /*
 576  * Machine interface: open a PIDs element.
 577  *
 578  * writer An instance of a machine interface writer.
 579  *
 580  * Returns zero if the element's value could be written.
 581  * Negative values indicate an error.
 582  */
 583 int mi_lttng_pids_open(struct mi_writer *writer);
 584
 585 /*
 586  * Machine interface: open a processes element.
 587  *
 588  * writer An instance of a machine interface writer.
 589  *
 590  * Returns zero if the element's value could be written.
 591  * Negative values indicate an error.
 592  */
 593 int mi_lttng_processes_open(struct mi_writer *writer);
 594
 595 /*
 596  * Machine interface of a Process.
 597  *
 598  * writer An instance of a machine interface writer.
 599  * pid A PID.
 600  *
 601  * is_open Defines whether or not the session element shall be closed.
 602  *         This should be used carefully and the client
 603  *         must close the pid element.
 604  *         Use case: nested addition information on a domain
 605  *                  ex: channel event.
 606  *
 607  * Returns zero if the element's value could be written.
 608  * Negative values indicate an error.
 609  */
 610 int mi_lttng_process(struct mi_writer *writer, pid_t pid , const char *name,
 611                 int is_open);
 612
 613 /*
 614  * TODO: move pid of lttng list -u to process semantic on mi api bump
 615  * Machine interface of a Process.
 616  *
 617  * writer An instance of a machine interface writer.
 618  * pid A PID.
 619  *
 620  * is_open Defines whether or not the session element shall be closed.
 621  *         This should be used carefully and the client
 622  *         must close the pid element.
 623  *         Use case: nested addition information on a domain
 624  *                  ex: channel event.
 625  *
 626  * Returns zero if the element's value could be written.
 627  * Negative values indicate an error.
 628  */
 629 int mi_lttng_pid(struct mi_writer *writer, pid_t pid , const char *name,
 630                 int is_open);
 631 /*
 632  * Machine interface: open a targets element.
 633  *
 634  * writer An instance of a machine interface writer.
 635  *
 636  * Returns zero if the element's value could be written.
 637  * Negative values indicate an error.
 638  */
 639 int mi_lttng_targets_open(struct mi_writer *writer);
 640
 641 /*
 642  * Machine interface for track/untrack a pid_target
 643  *
 644  * writer An instance of a machine interface writer.
 645  *
 646  * Returns zero if the element's value could be written.
 647  * Negative values indicate an error.
 648  */
 649 int mi_lttng_pid_target(struct mi_writer *writer, pid_t pid, int is_open);
 650
 651 /*
 652  * Machine interface of a context.
 653  *
 654  * writer An instance of a machine interface writer
 655  *
 656  * context An instance of a lttng_event_context
 657  *
 658  * is_open Define if we close the context element
 659  *         This should be used carefully and the client
 660  *         need to close the context element.
 661  * Returns zero if the element's value could be written.
 662  * Negative values indicate an error.
 663  */
 664 int mi_lttng_context(struct mi_writer *writer,
 665                 struct lttng_event_context *context, int is_open);
 666
 667 /*
 668  * Machine interface of a perf_counter_context.
 669  *
 670  * writer An instance of a machine interface writer
 671  *
 672  * contest An instance of a lttng_event_perf_counter_ctx
 673  *
 674  * Returns zero if the element's value could be written.
 675  * Negative values indicate an error.
 676  */
 677 int mi_lttng_perf_counter_context(struct mi_writer *writer,
 678                 struct lttng_event_perf_counter_ctx  *perf_context);
 679
 680 /*
 681  * Machine interface of the snapshot list_output.
 682  * It specifies the session for which we are listing snapshots,
 683  * and it opens a snapshots element to list a sequence
 684  * of snapshots.
 685  *
 686  * writer An instance of a machine interface writer.
 687  *
 688  * session_name: Snapshot output for session "session_name".
 689  *
 690  * Note: The client has to close the session and the snapshots elements after
 691  * having listed every lttng_snapshot_output.
 692  *
 693  * Returns zero if the element's value could be written.
 694  * Negative values indicate an error.
 695  */
 696 int mi_lttng_snapshot_output_session_name(struct mi_writer *writer,
 697                 const char *session_name);
 698
 699 /*
 700  * Machine interface of the snapshot output.
 701  * The machine interface serializes the following attributes:
 702  * - id: ID of the snapshot output.
 703  * - name: Name of the output.
 704  * - data_url : Destination of the output.
 705  * - ctrl_url: Destination of the output.
 706  * - max_size: total size of all stream combined.
 707  *
 708  * writer An instance of a machine interface writer.
 709  *
 710  * output: A list of snapshot_output.
 711  *
 712  * Returns zero if the element's value could be written.
 713  * Negative values indicate an error.
 714  */
 715 int mi_lttng_snapshot_list_output(struct mi_writer *writer,
 716                 struct lttng_snapshot_output *output);
 717
 718 /*
 719  * Machine interface of the output of the command snapshot del output
 720  * when deleting a snapshot either by id or by name.
 721  * If the snapshot was found and successfully deleted using its id,
 722  * it return the id of the snapshot and the current session name on which it
 723  * was attached.
 724  *
 725  * Otherwise, it do the same process with the name of the snapshot, if the
 726  * snapshot output id is undefined.
 727  *
 728  * writer An instance of a machine interface writer.
 729  *
 730  * id: ID of the snapshot output.
 731  *
 732  * name: Name of the snapshot.
 733  *
 734  * current_session_name: Session to which the snapshot belongs.
 735  *
 736  * Returns zero if the element's value could be written.
 737  * Negative values indicate an error.
 738  */
 739 int mi_lttng_snapshot_del_output(struct mi_writer *writer, int id,
 740                 const char *name, const char *current_session_name);
 741
 742 /*
 743  * Machine interface of the output of the command snapshot add output
 744  * when adding a snapshot from a user URL.
 745  *
 746  * If the snapshot was successfully added, the machine interface lists
 747  * these information:
 748  * - id: ID of the newly add snapshot output.
 749  * - current_session_name: Name of the session to which the output was added.
 750  * - ctrl_url: Destination of the output.
 751  * - max_size: total size of all stream combined.
 752  *
 753  * writer An instance of a machine interface writer.
 754  *
 755  * current_session_name: Session to which the snapshot belongs.
 756  *
 757  * n_ptr:
 758  *
 759  * output: iterator over a lttng_snapshot_output_list which contain
 760  * the snapshot output informations.
 761  *
 762  * Returns zero if the element's value could be written.
 763  * Negative values indicate an error.
 764  */
 765 int mi_lttng_snapshot_add_output(struct mi_writer *writer,
 766                 const char *current_session_name, const char *n_ptr,
 767                 struct lttng_snapshot_output *output);
 768
 769 /*
 770  * Machine interface of the output of the command snapshot
 771  * record  from a URL (if given).
 772  *
 773  * If the snapshot is successfully recorded from a url, the machine interface
 774  * output the following information:
 775  * - url: Destination of the output stored in the snapshot.
 776  *
 777  * Otherwise, the machine interface output the data and ctrl url received
 778  * from the command-line.
 779  *
 780  * writer An instance of a machine interface writer.
 781  *
 782  * current_session_name: Snapshot record for session "current_session_name".
 783  *
 784  * ctrl_url, data_url: Destination of the output receive from the command-line.
 785  *
 786  * Returns zero if the element's value could be written.
 787  * Negative values indicate an error.
 788  */
 789 int mi_lttng_snapshot_record(struct mi_writer *writer,
 790                 const char *current_session_name, const char *url,
 791                 const char *cmdline_ctrl_url, const char *cmdline_data_url);
 792
 793 #endif /* _MI_LTTNG_H */