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 extern const char * const mi_lttng_element_command_rotate;
  84 extern const char * const mi_lttng_element_command_enable_rotation;
  85 extern const char * const mi_lttng_element_command_disable_rotation;
  86
  87 /* Strings related to version command */
  88 extern const char * const mi_lttng_element_version;
  89 extern const char * const mi_lttng_element_version_commit;
  90 extern const char * const mi_lttng_element_version_description;
  91 extern const char * const mi_lttng_element_version_license;
  92 extern const char * const mi_lttng_element_version_major;
  93 extern const char * const mi_lttng_element_version_minor;
  94 extern const char * const mi_lttng_element_version_patch_level;
  95 extern const char * const mi_lttng_element_version_str;
  96 extern const char * const mi_lttng_element_version_web;
  97
  98 /* String related to a lttng_event_field */
  99 extern const char * const mi_lttng_element_event_field;
 100 extern const char * const mi_lttng_element_event_fields;
 101
 102 /* String related to lttng_event_perf_counter_ctx */
 103 extern const char * const mi_lttng_element_perf_counter_context;
 104
 105 /* Strings related to pid */
 106 extern const char * const mi_lttng_element_pid_id;
 107
 108 /* Strings related to save command */
 109 extern const char * const mi_lttng_element_save;
 110
 111 /* Strings related to load command */
 112 extern const char * const mi_lttng_element_load;
 113 LTTNG_HIDDEN const char * const mi_lttng_element_load_overrides;
 114 LTTNG_HIDDEN const char * const mi_lttng_element_load_override_url;
 115
 116 /* General element of mi_lttng */
 117 extern const char * const mi_lttng_element_empty;
 118 extern const char * const mi_lttng_element_id;
 119 extern const char * const mi_lttng_element_nowrite;
 120 extern const char * const mi_lttng_element_success;
 121 extern const char * const mi_lttng_element_type_enum;
 122 extern const char * const mi_lttng_element_type_float;
 123 extern const char * const mi_lttng_element_type_integer;
 124 extern const char * const mi_lttng_element_type_other;
 125 extern const char * const mi_lttng_element_type_string;
 126
 127 /* String related to loglevel */
 128 extern const char * const mi_lttng_loglevel_str_alert;
 129 extern const char * const mi_lttng_loglevel_str_crit;
 130 extern const char * const mi_lttng_loglevel_str_debug;
 131 extern const char * const mi_lttng_loglevel_str_debug_function;
 132 extern const char * const mi_lttng_loglevel_str_debug_line;
 133 extern const char * const mi_lttng_loglevel_str_debug_module;
 134 extern const char * const mi_lttng_loglevel_str_debug_process;
 135 extern const char * const mi_lttng_loglevel_str_debug_program;
 136 extern const char * const mi_lttng_loglevel_str_debug_system;
 137 extern const char * const mi_lttng_loglevel_str_debug_unit;
 138 extern const char * const mi_lttng_loglevel_str_emerg;
 139 extern const char * const mi_lttng_loglevel_str_err;
 140 extern const char * const mi_lttng_loglevel_str_info;
 141 extern const char * const mi_lttng_loglevel_str_notice;
 142 extern const char * const mi_lttng_loglevel_str_unknown;
 143 extern const char * const mi_lttng_loglevel_str_warning;
 144
 145 /* String related to loglevel JUL */
 146 extern const char * const mi_lttng_loglevel_str_jul_all;
 147 extern const char * const mi_lttng_loglevel_str_jul_config;
 148 extern const char * const mi_lttng_loglevel_str_jul_fine;
 149 extern const char * const mi_lttng_loglevel_str_jul_finer;
 150 extern const char * const mi_lttng_loglevel_str_jul_finest;
 151 extern const char * const mi_lttng_loglevel_str_jul_info;
 152 extern const char * const mi_lttng_loglevel_str_jul_off;
 153 extern const char * const mi_lttng_loglevel_str_jul_severe;
 154 extern const char * const mi_lttng_loglevel_str_jul_warning;
 155
 156 /* String related to loglevel Log4j */
 157 extern const char * const mi_lttng_loglevel_str_log4j_off;
 158 extern const char * const mi_lttng_loglevel_str_log4j_fatal;
 159 extern const char * const mi_lttng_loglevel_str_log4j_error;
 160 extern const char * const mi_lttng_loglevel_str_log4j_warn;
 161 extern const char * const mi_lttng_loglevel_str_log4j_info;
 162 extern const char * const mi_lttng_loglevel_str_log4j_debug;
 163 extern const char * const mi_lttng_loglevel_str_log4j_trace;
 164 extern const char * const mi_lttng_loglevel_str_log4j_all;
 165
 166 /* String related to loglevel Python */
 167 extern const char * const mi_lttng_loglevel_str_python_critical;
 168 extern const char * const mi_lttng_loglevel_str_python_error;
 169 extern const char * const mi_lttng_loglevel_str_python_warning;
 170 extern const char * const mi_lttng_loglevel_str_python_info;
 171 extern const char * const mi_lttng_loglevel_str_python_debug;
 172 extern const char * const mi_lttng_loglevel_str_python_notset;
 173
 174 /* String related to loglevel type */
 175 extern const char * const mi_lttng_loglevel_type_all;
 176 extern const char * const mi_lttng_loglevel_type_range;
 177 extern const char * const mi_lttng_loglevel_type_single;
 178 extern const char * const mi_lttng_loglevel_type_unknown;
 179
 180 /* String related to a lttng_snapshot */
 181 extern const char * const mi_lttng_element_snapshot_ctrl_url;
 182 extern const char * const mi_lttng_element_snapshot_data_url;
 183 extern const char * const mi_lttng_element_snapshot_max_size;
 184 extern const char * const mi_lttng_element_snapshot_n_ptr;
 185 extern const char * const mi_lttng_element_snapshot_session_name;
 186 extern const char * const mi_lttng_element_snapshots;
 187
 188 /* String related to track/untrack command */
 189 const char * const mi_lttng_element_track_untrack_all_wildcard;
 190
 191 LTTNG_HIDDEN const char * const mi_lttng_element_session_name;
 192
 193 /* String related to rotate command */
 194 LTTNG_HIDDEN const char * const mi_lttng_element_rotation;
 195 LTTNG_HIDDEN const char * const mi_lttng_element_rotations;
 196 LTTNG_HIDDEN const char * const mi_lttng_element_rotate_status;
 197 LTTNG_HIDDEN const char * const mi_lttng_element_rotation_schedule;
 198
 199 /* Utility string function  */
 200 const char *mi_lttng_loglevel_string(int value, enum lttng_domain_type domain);
 201 const char *mi_lttng_logleveltype_string(enum lttng_loglevel_type value);
 202 const char *mi_lttng_eventfieldtype_string(enum lttng_event_field_type value);
 203 const char *mi_lttng_domaintype_string(enum lttng_domain_type value);
 204 const char *mi_lttng_buffertype_string(enum lttng_buffer_type value);
 205
 206 /*
 207  * Create an instance of a machine interface writer.
 208  *
 209  * fd_output File to which the XML content must be written. The file will be
 210  * closed once the mi_writer has been destroyed.
 211  *
 212  * Returns an instance of a machine interface writer on success, NULL on
 213  * error.
 214  */
 215 struct mi_writer *mi_lttng_writer_create(int fd_output, int mi_output_type);
 216
 217 /*
 218  * Destroy an instance of a machine interface writer.
 219  *
 220  * writer An instance of a machine interface writer.
 221  *
 222  * Returns zero if the XML document could be closed cleanly. Negative values
 223  * indicate an error.
 224  */
 225 int mi_lttng_writer_destroy(struct mi_writer *writer);
 226
 227 /*
 228  * Open a command tag and add it's name node.
 229  *
 230  * writer An instance of a machine interface writer.
 231  * command The command name.
 232  *
 233  * Returns zero if the XML document could be closed cleanly.
 234  * Negative values indicate an error.
 235  */
 236 int mi_lttng_writer_command_open(struct mi_writer *writer, const char *command);
 237
 238 /*
 239  * Close a command tag.
 240  *
 241  * writer An instance of a machine interface writer.
 242  *
 243  * Returns zero if the XML document could be closed cleanly.
 244  * Negative values indicate an error.
 245  */
 246 int mi_lttng_writer_command_close(struct mi_writer *writer);
 247
 248 /*
 249  * Open an element tag.
 250  *
 251  * writer An instance of a machine interface writer.
 252  * element_name Element tag name.
 253  *
 254  * Returns zero if the XML document could be closed cleanly.
 255  * Negative values indicate an error.
 256  */
 257 int mi_lttng_writer_open_element(struct mi_writer *writer,
 258                 const char *element_name);
 259
 260 /*
 261  * Close the current element tag.
 262  *
 263  * writer An instance of a machine interface writer.
 264  *
 265  * Returns zero if the XML document could be closed cleanly.
 266  * Negative values indicate an error.
 267  */
 268 int mi_lttng_writer_close_element(struct mi_writer *writer);
 269
 270 /*
 271  * Close multiple element.
 272  *
 273  * writer An instance of a machine interface writer.
 274  * nb_element Number of elements.
 275  *
 276  * Returns zero if the XML document could be closed cleanly.
 277  * Negative values indicate an error.
 278  */
 279 int mi_lttng_close_multi_element(struct mi_writer *writer,
 280                 unsigned int nb_element);
 281
 282 /*
 283  * Write an element of type unsigned int.
 284  *
 285  * writer An instance of a machine interface writer.
 286  * element_name Element name.
 287  * value Unsigned 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_unsigned_int(struct mi_writer *writer,
 293                 const char *element_name, uint64_t value);
 294
 295 /*
 296  * Write an element of type signed int.
 297  *
 298  * writer An instance of a machine interface writer.
 299  * element_name Element name.
 300  * value Signed int 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_signed_int(struct mi_writer *writer,
 306                 const char *element_name, int64_t value);
 307
 308 /*
 309  * Write an element of type boolean.
 310  *
 311  * writer An instance of a machine interface writer.
 312  * element_name Element name.
 313  * value Boolean 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_bool(struct mi_writer *writer,
 319                 const char *element_name, int value);
 320
 321 /*
 322  * Write an element of type string.
 323  *
 324  * writer An instance of a machine interface writer.
 325  * element_name Element name.
 326  * value String value of the element.
 327  *
 328  * Returns zero if the element's value could be written.
 329  * Negative values indicate an error.
 330  */
 331 int mi_lttng_writer_write_element_string(struct mi_writer *writer,
 332                 const char *element_name, const char *value);
 333
 334 /*
 335  * Machine interface of struct version.
 336  *
 337  * writer An instance of a machine interface writer.
 338  * version Version struct.
 339  * lttng_description String value of the version description.
 340  * lttng_license String value of the version license.
 341  *
 342  * Returns zero if the element's value could be written.
 343  * Negative values indicate an error.
 344  */
 345 int mi_lttng_version(struct mi_writer *writer, struct mi_lttng_version *version,
 346                 const char *lttng_description, const char *lttng_license);
 347
 348 /*
 349  * Machine interface: open a sessions element.
 350  *
 351  * writer An instance of a machine interface writer.
 352  *
 353  * Returns zero if the element's value could be written.
 354  * Negative values indicate an error.
 355  */
 356 int mi_lttng_sessions_open(struct mi_writer *writer);
 357
 358 /*
 359  * Machine interface of struct session.
 360  *
 361  * writer An instance of a machine interface writer.
 362  * session An instance of a session.
 363  * is_open Defines whether or not the session element shall be closed.
 364  *         This should be used carefully and the client
 365  *         must close the session element.
 366  *         Use case: nested additional information on a session
 367  *                  ex: domain,channel event.
 368  *
 369  * Returns zero if the element's value could be written.
 370  * Negative values indicate an error.
 371  */
 372 int mi_lttng_session(struct mi_writer *writer,
 373                 struct lttng_session *session, int is_open);
 374
 375 /*
 376  * Machine interface: open a domains element.
 377  *
 378  * writer An instance of a machine interface writer.
 379  *
 380  * Returns zero if the element's value could be written.
 381  * Negative values indicate an error.
 382  */
 383 int mi_lttng_domains_open(struct mi_writer *writer);
 384
 385 /*
 386  * Machine interface of struct domain.
 387  *
 388  * writer An instance of a machine interface writer.
 389  * domain An instance of a domain.
 390  *
 391  * is_open Defines whether or not the session element shall be closed.
 392  *         This should be used carefully and the client
 393  *         must close the domain element.
 394  *         Use case: nested addition information on a domain
 395  *                  ex: channel event.
 396  *
 397  * Returns zero if the element's value could be written.
 398  * Negative values indicate an error.
 399  */
 400 int mi_lttng_domain(struct mi_writer *writer,
 401                 struct lttng_domain *domain, int is_open);
 402
 403 /*
 404  * Machine interface: open a channels element.
 405  *
 406  * writer An instance of a machine interface writer.
 407  *
 408  * Returns zero if the element's value could be written.
 409  * Negative values indicate an error.
 410  */
 411 int mi_lttng_channels_open(struct mi_writer *writer);
 412
 413 /*
 414  * Machine interface of struct channel.
 415  *
 416  * writer An instance of a machine interface writer.
 417  * channel An instance of a channel.
 418  *
 419  * is_open Defines whether or not the session element shall be closed.
 420  *         This should be used carefully and the client
 421  *         must close the channel element.
 422  *         Use case: nested addition information on a channel.
 423  *                  ex: channel event.
 424  *
 425  * Returns zero if the element's value could be written.
 426  * Negative values indicate an error.
 427  */
 428 int mi_lttng_channel(struct mi_writer *writer,
 429                 struct lttng_channel *channel, int is_open);
 430
 431 /*
 432  * Machine interface of struct channel_attr.
 433  *
 434  * writer An instance of a machine interface writer.
 435  * attr An instance of a channel_attr struct.
 436  *
 437  * Returns zero if the element's value could be written.
 438  * Negative values indicate an error.
 439  */
 440 int mi_lttng_channel_attr(struct mi_writer *writer,
 441                 struct lttng_channel_attr *attr);
 442
 443 /*
 444 * Machine interface for event common attributes.
 445 *
 446 * writer An instance of a mi writer.
 447 * event single trace event.
 448 *
 449 * The common attribute are:
 450 * - mi event element
 451 * - event name
 452 * - event type
 453 * - enabled tag
 454 * - event filter
 455 *
 456 * Returns zero if the element's value could be written.
 457 * Negative values indicate an error.
 458 */
 459 int mi_lttng_event_common_attributes(struct mi_writer *writer,
 460                 struct lttng_event *event);
 461
 462 /*
 463  * Machine interface for kernel tracepoint event with a loglevel.
 464  *
 465  * writer An instance of a mi writer.
 466  * event single trace event.
 467  * domain Event's domain
 468  *
 469  * Returns zero if the element's value could be written.
 470  * Negative values indicate an error.
 471  */
 472 int mi_lttng_event_tracepoint_loglevel(struct mi_writer *writer,
 473                 struct lttng_event *event, enum lttng_domain_type domain);
 474
 475 /*
 476  * Machine interface for kernel tracepoint event with no loglevel.
 477  *
 478  * writer An instance of a mi writer.
 479  * event single trace event.
 480  *
 481  * Returns zero if the element's value could be written.
 482  * Negative values indicate an error.
 483  */
 484 int mi_lttng_event_tracepoint_no_loglevel(struct mi_writer *writer,
 485                 struct lttng_event *event);
 486
 487 /*
 488  * Machine interface for kernel function and probe event.
 489  *
 490  * writer An instance of a mi writer.
 491  * event single trace event.
 492  *
 493  * Returns zero if the element's value could be written.
 494  * Negative values indicate an error.
 495  */
 496 int mi_lttng_event_function_probe(struct mi_writer *writer,
 497                 struct lttng_event *event);
 498
 499 /*
 500  * Machine interface for kernel function entry event.
 501  *
 502  * writer An instance of a mi writer.
 503  * event single trace event.
 504  *
 505  * Returns zero if the element's value could be written.
 506  * Negative values indicate an error.
 507  */
 508 int mi_lttng_event_function_entry(struct mi_writer *writer,
 509                 struct lttng_event *event);
 510
 511 /*
 512  * Machine interface: open an events element.
 513  *
 514  * writer An instance of a machine interface writer.
 515  *
 516  * Returns zero if the element's value could be written.
 517  * Negative values indicate an error.
 518  */
 519 int mi_lttng_events_open(struct mi_writer *writer);
 520
 521 /*
 522  * Machine interface for printing an event.
 523  * The trace event type currently supported are:
 524  *  TRACEPOINT,
 525  *  PROBE,
 526  *  FUNCTION,
 527  *  FUNCTION_ENTRY,
 528  *  SYSCALL
 529  *
 530  * writer An instance of a mi writer.
 531  * event single trace event.
 532  * is_open Defines whether or not the session element shall be closed.
 533  *         This should be used carefully and the client
 534  *         must close the event element.
 535  *         Use case: nested additional information
 536  * domain Event's domain
 537  *
 538  * Returns zero if the element's value could be written.
 539  * Negative values indicate an error.
 540  */
 541 int mi_lttng_event(struct mi_writer *writer, struct lttng_event *event,
 542                 int is_open, enum lttng_domain_type domain);
 543
 544 /*
 545  * Machine interface for struct lttng_event_field.
 546  *
 547  * writer An instance of a mi writer.
 548  * field An event_field instance.
 549  *
 550  * Returns zero if the element's value could be written.
 551  * Negative values indicate an error.
 552  */
 553 int mi_lttng_event_field(struct mi_writer *writer,
 554                 struct lttng_event_field *field);
 555
 556 /*
 557  * Machine interface: open a event_fields element.
 558  *
 559  * writer An instance of a machine interface writer.
 560  *
 561  * Returns zero if the element have be written.
 562  * Negative values indicate an error.
 563  */
 564 int mi_lttng_event_fields_open(struct mi_writer *writer);
 565
 566 /*
 567  * Machine interface: open a trackers element.
 568  *
 569  * writer An instance of a machine interface writer.
 570  *
 571  * Returns zero if the element's value could be written.
 572  * Negative values indicate an error.
 573  */
 574 int mi_lttng_trackers_open(struct mi_writer *writer);
 575
 576 /*
 577  * Machine interface: open a pid_tracker element.
 578  *
 579  * writer An instance of a machine interface writer.
 580  *
 581  * Returns zero if the element's value could be written.
 582  * Negative values indicate an error.
 583  *
 584  * Note: A targets element is also opened for each tracker definition
 585  */
 586 int mi_lttng_pid_tracker_open(struct mi_writer *writer);
 587
 588 /*
 589  * Machine interface: open a PIDs element.
 590  *
 591  * writer An instance of a machine interface writer.
 592  *
 593  * Returns zero if the element's value could be written.
 594  * Negative values indicate an error.
 595  */
 596 int mi_lttng_pids_open(struct mi_writer *writer);
 597
 598 /*
 599  * Machine interface: open a processes element.
 600  *
 601  * writer An instance of a machine interface writer.
 602  *
 603  * Returns zero if the element's value could be written.
 604  * Negative values indicate an error.
 605  */
 606 int mi_lttng_processes_open(struct mi_writer *writer);
 607
 608 /*
 609  * Machine interface of a Process.
 610  *
 611  * writer An instance of a machine interface writer.
 612  * pid A PID.
 613  *
 614  * is_open Defines whether or not the session element shall be closed.
 615  *         This should be used carefully and the client
 616  *         must close the pid element.
 617  *         Use case: nested addition information on a domain
 618  *                  ex: channel event.
 619  *
 620  * Returns zero if the element's value could be written.
 621  * Negative values indicate an error.
 622  */
 623 int mi_lttng_process(struct mi_writer *writer, pid_t pid , const char *name,
 624                 int is_open);
 625
 626 /*
 627  * TODO: move pid of lttng list -u to process semantic on mi api bump
 628  * Machine interface of a Process.
 629  *
 630  * writer An instance of a machine interface writer.
 631  * pid A PID.
 632  *
 633  * is_open Defines whether or not the session element shall be closed.
 634  *         This should be used carefully and the client
 635  *         must close the pid element.
 636  *         Use case: nested addition information on a domain
 637  *                  ex: channel event.
 638  *
 639  * Returns zero if the element's value could be written.
 640  * Negative values indicate an error.
 641  */
 642 int mi_lttng_pid(struct mi_writer *writer, pid_t pid , const char *name,
 643                 int is_open);
 644 /*
 645  * Machine interface: open a targets element.
 646  *
 647  * writer An instance of a machine interface writer.
 648  *
 649  * Returns zero if the element's value could be written.
 650  * Negative values indicate an error.
 651  */
 652 int mi_lttng_targets_open(struct mi_writer *writer);
 653
 654 /*
 655  * Machine interface for track/untrack a pid_target
 656  *
 657  * writer An instance of a machine interface writer.
 658  *
 659  * Returns zero if the element's value could be written.
 660  * Negative values indicate an error.
 661  */
 662 int mi_lttng_pid_target(struct mi_writer *writer, pid_t pid, int is_open);
 663
 664 /*
 665  * Machine interface of a context.
 666  *
 667  * writer An instance of a machine interface writer
 668  *
 669  * context An instance of a lttng_event_context
 670  *
 671  * is_open Define if we close the context element
 672  *         This should be used carefully and the client
 673  *         need to close the context element.
 674  * Returns zero if the element's value could be written.
 675  * Negative values indicate an error.
 676  */
 677 int mi_lttng_context(struct mi_writer *writer,
 678                 struct lttng_event_context *context, int is_open);
 679
 680 /*
 681  * Machine interface of a perf_counter_context.
 682  *
 683  * writer An instance of a machine interface writer
 684  *
 685  * contest An instance of a lttng_event_perf_counter_ctx
 686  *
 687  * Returns zero if the element's value could be written.
 688  * Negative values indicate an error.
 689  */
 690 int mi_lttng_perf_counter_context(struct mi_writer *writer,
 691                 struct lttng_event_perf_counter_ctx  *perf_context);
 692
 693 /*
 694  * Machine interface of the snapshot list_output.
 695  * It specifies the session for which we are listing snapshots,
 696  * and it opens a snapshots element to list a sequence
 697  * of snapshots.
 698  *
 699  * writer An instance of a machine interface writer.
 700  *
 701  * session_name: Snapshot output for session "session_name".
 702  *
 703  * Note: The client has to close the session and the snapshots elements after
 704  * having listed every lttng_snapshot_output.
 705  *
 706  * Returns zero if the element's value could be written.
 707  * Negative values indicate an error.
 708  */
 709 int mi_lttng_snapshot_output_session_name(struct mi_writer *writer,
 710                 const char *session_name);
 711
 712 /*
 713  * Machine interface of the snapshot output.
 714  * The machine interface serializes the following attributes:
 715  * - id: ID of the snapshot output.
 716  * - name: Name of the output.
 717  * - data_url : Destination of the output.
 718  * - ctrl_url: Destination of the output.
 719  * - max_size: total size of all stream combined.
 720  *
 721  * writer An instance of a machine interface writer.
 722  *
 723  * output: A list of snapshot_output.
 724  *
 725  * Returns zero if the element's value could be written.
 726  * Negative values indicate an error.
 727  */
 728 int mi_lttng_snapshot_list_output(struct mi_writer *writer,
 729                 struct lttng_snapshot_output *output);
 730
 731 /*
 732  * Machine interface of the output of the command snapshot del output
 733  * when deleting a snapshot either by id or by name.
 734  * If the snapshot was found and successfully deleted using its id,
 735  * it return the id of the snapshot and the current session name on which it
 736  * was attached.
 737  *
 738  * Otherwise, it do the same process with the name of the snapshot, if the
 739  * snapshot output id is undefined.
 740  *
 741  * writer An instance of a machine interface writer.
 742  *
 743  * id: ID of the snapshot output.
 744  *
 745  * name: Name of the snapshot.
 746  *
 747  * current_session_name: Session to which the snapshot belongs.
 748  *
 749  * Returns zero if the element's value could be written.
 750  * Negative values indicate an error.
 751  */
 752 int mi_lttng_snapshot_del_output(struct mi_writer *writer, int id,
 753                 const char *name, const char *current_session_name);
 754
 755 /*
 756  * Machine interface of the output of the command snapshot add output
 757  * when adding a snapshot from a user URL.
 758  *
 759  * If the snapshot was successfully added, the machine interface lists
 760  * these information:
 761  * - id: ID of the newly add snapshot output.
 762  * - current_session_name: Name of the session to which the output was added.
 763  * - ctrl_url: Destination of the output.
 764  * - max_size: total size of all stream combined.
 765  *
 766  * writer An instance of a machine interface writer.
 767  *
 768  * current_session_name: Session to which the snapshot belongs.
 769  *
 770  * n_ptr:
 771  *
 772  * output: iterator over a lttng_snapshot_output_list which contain
 773  * the snapshot output informations.
 774  *
 775  * Returns zero if the element's value could be written.
 776  * Negative values indicate an error.
 777  */
 778 int mi_lttng_snapshot_add_output(struct mi_writer *writer,
 779                 const char *current_session_name, const char *n_ptr,
 780                 struct lttng_snapshot_output *output);
 781
 782 /*
 783  * Machine interface of the output of the command snapshot
 784  * record  from a URL (if given).
 785  *
 786  * If the snapshot is successfully recorded from a url, the machine interface
 787  * output the following information:
 788  * - url: Destination of the output stored in the snapshot.
 789  *
 790  * Otherwise, the machine interface output the data and ctrl url received
 791  * from the command-line.
 792  *
 793  * writer An instance of a machine interface writer.
 794  *
 795  * current_session_name: Snapshot record for session "current_session_name".
 796  *
 797  * ctrl_url, data_url: Destination of the output receive from the command-line.
 798  *
 799  * Returns zero if the element's value could be written.
 800  * Negative values indicate an error.
 801  */
 802 int mi_lttng_snapshot_record(struct mi_writer *writer,
 803                 const char *current_session_name, const char *url,
 804                 const char *cmdline_ctrl_url, const char *cmdline_data_url);
 805
 806 #endif /* _MI_LTTNG_H */