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  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License, version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc., 51
  16  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #ifndef _MI_LTTNG_H
  20 #define _MI_LTTNG_H
  21
  22 #include <stdint.h>
  23
  24 #include <common/error.h>
  25 #include <common/macros.h>
  26 #include <common/config/config.h>
  27 #include <lttng/lttng.h>
  28
  29 /* Don't want to reference snapshot-internal.h here */
  30 struct lttng_snapshot_output;
  31
  32 /* Instance of a machine interface writer. */
  33 struct mi_writer {
  34         struct config_writer *writer;
  35         enum lttng_mi_output_type type;
  36 };
  37
  38 /*
  39  * Version information for the machine interface.
  40  */
  41 struct mi_lttng_version {
  42         char version[NAME_MAX]; /* Version number of package */
  43         uint32_t version_major; /* LTTng-Tools major version number */
  44         uint32_t version_minor; /* LTTng-Tools minor version number */
  45         uint32_t version_patchlevel; /* LTTng-Tools patchlevel version number */
  46         char version_commit[NAME_MAX]; /* Commit hash of the current version */
  47         char version_name[NAME_MAX];
  48         char package_url[NAME_MAX]; /* Define to the home page for this package. */
  49 };
  50
  51 /* Strings related to command */
  52 extern const char * const mi_lttng_element_command;
  53 extern const char * const mi_lttng_element_command_action;
  54 extern const char * const mi_lttng_element_command_add_context;
  55 extern const char * const mi_lttng_element_command_calibrate;
  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_name;
  65 extern const char * const mi_lttng_element_command_output;
  66 extern const char * const mi_lttng_element_command_save;
  67 extern const char * const mi_lttng_element_command_set_session;
  68 extern const char * const mi_lttng_element_command_snapshot;
  69 extern const char * const mi_lttng_element_command_snapshot_add;
  70 extern const char * const mi_lttng_element_command_snapshot_del;
  71 extern const char * const mi_lttng_element_command_snapshot_list;
  72 extern const char * const mi_lttng_element_command_snapshot_record;
  73 extern const char * const mi_lttng_element_command_start;
  74 extern const char * const mi_lttng_element_command_stop;
  75 extern const char * const mi_lttng_element_command_success;
  76 extern const char * const mi_lttng_element_command_track;
  77 extern const char * const mi_lttng_element_command_untrack;
  78 extern const char * const mi_lttng_element_command_version;
  79
  80 /* Strings related to version command */
  81 extern const char * const mi_lttng_element_version;
  82 extern const char * const mi_lttng_element_version_commit;
  83 extern const char * const mi_lttng_element_version_description;
  84 extern const char * const mi_lttng_element_version_license;
  85 extern const char * const mi_lttng_element_version_major;
  86 extern const char * const mi_lttng_element_version_minor;
  87 extern const char * const mi_lttng_element_version_patch_level;
  88 extern const char * const mi_lttng_element_version_str;
  89 extern const char * const mi_lttng_element_version_web;
  90
  91 /* String related to a lttng_event_field */
  92 extern const char * const mi_lttng_element_event_field;
  93 extern const char * const mi_lttng_element_event_fields;
  94
  95 /* String related to lttng_event_context */
  96 extern const char * const mi_lttng_context_type_perf_counter;
  97 extern const char * const mi_lttng_context_type_perf_cpu_counter;
  98 extern const char * const mi_lttng_context_type_perf_thread_counter;
  99
 100 /* String related to lttng_event_perf_counter_ctx */
 101 extern const char * const mi_lttng_element_perf_counter_context;
 102
 103 /* Strings related to pid */
 104 extern const char * const mi_lttng_element_processes;
 105 extern const char * const mi_lttng_element_process;
 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
 114 /* General element of mi_lttng */
 115 extern const char * const mi_lttng_element_empty;
 116 extern const char * const mi_lttng_element_id;
 117 extern const char * const mi_lttng_element_nowrite;
 118 extern const char * const mi_lttng_element_success;
 119 extern const char * const mi_lttng_element_type_enum;
 120 extern const char * const mi_lttng_element_type_float;
 121 extern const char * const mi_lttng_element_type_integer;
 122 extern const char * const mi_lttng_element_type_other;
 123 extern const char * const mi_lttng_element_type_string;
 124
 125 /* String related to loglevel */
 126 extern const char * const mi_lttng_loglevel_str_alert;
 127 extern const char * const mi_lttng_loglevel_str_crit;
 128 extern const char * const mi_lttng_loglevel_str_debug;
 129 extern const char * const mi_lttng_loglevel_str_debug_function;
 130 extern const char * const mi_lttng_loglevel_str_debug_line;
 131 extern const char * const mi_lttng_loglevel_str_debug_module;
 132 extern const char * const mi_lttng_loglevel_str_debug_process;
 133 extern const char * const mi_lttng_loglevel_str_debug_program;
 134 extern const char * const mi_lttng_loglevel_str_debug_system;
 135 extern const char * const mi_lttng_loglevel_str_debug_unit;
 136 extern const char * const mi_lttng_loglevel_str_emerg;
 137 extern const char * const mi_lttng_loglevel_str_err;
 138 extern const char * const mi_lttng_loglevel_str_info;
 139 extern const char * const mi_lttng_loglevel_str_notice;
 140 extern const char * const mi_lttng_loglevel_str_unknown;
 141 extern const char * const mi_lttng_loglevel_str_warning;
 142
 143 /* String related to loglevel JUL */
 144 extern const char * const mi_lttng_loglevel_str_jul_all;
 145 extern const char * const mi_lttng_loglevel_str_jul_config;
 146 extern const char * const mi_lttng_loglevel_str_jul_fine;
 147 extern const char * const mi_lttng_loglevel_str_jul_finer;
 148 extern const char * const mi_lttng_loglevel_str_jul_finest;
 149 extern const char * const mi_lttng_loglevel_str_jul_info;
 150 extern const char * const mi_lttng_loglevel_str_jul_off;
 151 extern const char * const mi_lttng_loglevel_str_jul_severe;
 152 extern const char * const mi_lttng_loglevel_str_jul_warning;
 153
 154 /* String related to loglevel Log4j */
 155 extern const char * const mi_lttng_loglevel_str_log4j_off;
 156 extern const char * const mi_lttng_loglevel_str_log4j_fatal;
 157 extern const char * const mi_lttng_loglevel_str_log4j_error;
 158 extern const char * const mi_lttng_loglevel_str_log4j_warn;
 159 extern const char * const mi_lttng_loglevel_str_log4j_info;
 160 extern const char * const mi_lttng_loglevel_str_log4j_debug;
 161 extern const char * const mi_lttng_loglevel_str_log4j_trace;
 162 extern const char * const mi_lttng_loglevel_str_log4j_all;
 163
 164 /* String related to loglevel Python */
 165 extern const char * const mi_lttng_loglevel_str_python_critical;
 166 extern const char * const mi_lttng_loglevel_str_python_error;
 167 extern const char * const mi_lttng_loglevel_str_python_warning;
 168 extern const char * const mi_lttng_loglevel_str_python_info;
 169 extern const char * const mi_lttng_loglevel_str_python_debug;
 170 extern const char * const mi_lttng_loglevel_str_python_notset;
 171
 172 /* String related to loglevel type */
 173 extern const char * const mi_lttng_loglevel_type_all;
 174 extern const char * const mi_lttng_loglevel_type_range;
 175 extern const char * const mi_lttng_loglevel_type_single;
 176 extern const char * const mi_lttng_loglevel_type_unknown;
 177
 178 /* Sting related to lttng_calibrate */
 179 extern const char * const mi_lttng_element_calibrate;
 180 extern const char * const mi_lttng_element_calibrate_function;
 181
 182 /* String related to a lttng_snapshot */
 183 extern const char * const mi_lttng_element_snapshot_ctrl_url;
 184 extern const char * const mi_lttng_element_snapshot_data_url;
 185 extern const char * const mi_lttng_element_snapshot_max_size;
 186 extern const char * const mi_lttng_element_snapshot_n_ptr;
 187 extern const char * const mi_lttng_element_snapshot_session_name;
 188 extern const char * const mi_lttng_element_snapshots;
 189
 190 /* Utility string function  */
 191 const char *mi_lttng_loglevel_string(int value, enum lttng_domain_type domain);
 192 const char *mi_lttng_logleveltype_string(enum lttng_loglevel_type value);
 193 const char *mi_lttng_eventfieldtype_string(enum lttng_event_field_type value);
 194 const char *mi_lttng_domaintype_string(enum lttng_domain_type value);
 195 const char *mi_lttng_buffertype_string(enum lttng_buffer_type value);
 196 const char *mi_lttng_calibratetype_string(enum lttng_calibrate_type val);
 197
 198 /* String related to track/untrack command */
 199 const char * const mi_lttng_element_track_untrack_all_wildcard;
 200
 201 /*
 202  * Create an instance of a machine interface writer.
 203  *
 204  * fd_output File to which the XML content must be written. The file will be
 205  * closed once the mi_writer has been destroyed.
 206  *
 207  * Returns an instance of a machine interface writer on success, NULL on
 208  * error.
 209  */
 210 struct mi_writer *mi_lttng_writer_create(int fd_output, int mi_output_type);
 211
 212 /*
 213  * Destroy an instance of a machine interface writer.
 214  *
 215  * writer An instance of a machine interface writer.
 216  *
 217  * Returns zero if the XML document could be closed cleanly. Negative values
 218  * indicate an error.
 219  */
 220 int mi_lttng_writer_destroy(struct mi_writer *writer);
 221
 222 /*
 223  * Open a command tag and add it's name node.
 224  *
 225  * writer An instance of a machine interface writer.
 226  * command The command name.
 227  *
 228  * Returns zero if the XML document could be closed cleanly.
 229  * Negative values indicate an error.
 230  */
 231 int mi_lttng_writer_command_open(struct mi_writer *writer, const char *command);
 232
 233 /*
 234  * Close a command tag.
 235  *
 236  * writer An instance of a machine interface writer.
 237  *
 238  * Returns zero if the XML document could be closed cleanly.
 239  * Negative values indicate an error.
 240  */
 241 int mi_lttng_writer_command_close(struct mi_writer *writer);
 242
 243 /*
 244  * Open an element tag.
 245  *
 246  * writer An instance of a machine interface writer.
 247  * element_name Element tag name.
 248  *
 249  * Returns zero if the XML document could be closed cleanly.
 250  * Negative values indicate an error.
 251  */
 252 int mi_lttng_writer_open_element(struct mi_writer *writer,
 253                 const char *element_name);
 254
 255 /*
 256  * Close the current element tag.
 257  *
 258  * writer An instance of a machine interface writer.
 259  *
 260  * Returns zero if the XML document could be closed cleanly.
 261  * Negative values indicate an error.
 262  */
 263 int mi_lttng_writer_close_element(struct mi_writer *writer);
 264
 265 /*
 266  * Close multiple element.
 267  *
 268  * writer An instance of a machine interface writer.
 269  * nb_element Number of elements.
 270  *
 271  * Returns zero if the XML document could be closed cleanly.
 272  * Negative values indicate an error.
 273  */
 274 int mi_lttng_close_multi_element(struct mi_writer *writer,
 275                 unsigned int nb_element);
 276
 277 /*
 278  * Write an element of type unsigned int.
 279  *
 280  * writer An instance of a machine interface writer.
 281  * element_name Element name.
 282  * value Unsigned int value of the element
 283  *
 284  * Returns zero if the element's value could be written.
 285  * Negative values indicate an error.
 286  */
 287 int mi_lttng_writer_write_element_unsigned_int(struct mi_writer *writer,
 288                 const char *element_name, uint64_t value);
 289
 290 /*
 291  * Write an element of type signed int.
 292  *
 293  * writer An instance of a machine interface writer.
 294  * element_name Element name.
 295  * value Signed int value of the element.
 296  *
 297  * Returns zero if the element's value could be written.
 298  * Negative values indicate an error.
 299  */
 300 int mi_lttng_writer_write_element_signed_int(struct mi_writer *writer,
 301                 const char *element_name, int64_t value);
 302
 303 /*
 304  * Write an element of type boolean.
 305  *
 306  * writer An instance of a machine interface writer.
 307  * element_name Element name.
 308  * value Boolean value of the element.
 309  *
 310  * Returns zero if the element's value could be written.
 311  * Negative values indicate an error.
 312  */
 313 int mi_lttng_writer_write_element_bool(struct mi_writer *writer,
 314                 const char *element_name, int value);
 315
 316 /*
 317  * Write an element of type string.
 318  *
 319  * writer An instance of a machine interface writer.
 320  * element_name Element name.
 321  * value String value of the element.
 322  *
 323  * Returns zero if the element's value could be written.
 324  * Negative values indicate an error.
 325  */
 326 int mi_lttng_writer_write_element_string(struct mi_writer *writer,
 327                 const char *element_name, const char *value);
 328
 329 /*
 330  * Machine interface of struct version.
 331  *
 332  * writer An instance of a machine interface writer.
 333  * version Version struct.
 334  * lttng_description String value of the version description.
 335  * lttng_license String value of the version license.
 336  *
 337  * Returns zero if the element's value could be written.
 338  * Negative values indicate an error.
 339  */
 340 int mi_lttng_version(struct mi_writer *writer, struct mi_lttng_version *version,
 341                 const char *lttng_description, const char *lttng_license);
 342
 343 /*
 344  * Machine interface: open a sessions element.
 345  *
 346  * writer An instance of a machine interface writer.
 347  *
 348  * Returns zero if the element's value could be written.
 349  * Negative values indicate an error.
 350  */
 351 int mi_lttng_sessions_open(struct mi_writer *writer);
 352
 353 /*
 354  * Machine interface of struct session.
 355  *
 356  * writer An instance of a machine interface writer.
 357  * session An instance of a session.
 358  * is_open Defines whether or not the session element shall be closed.
 359  *         This should be used carefully and the client
 360  *         must close the session element.
 361  *         Use case: nested additional information on a session
 362  *                  ex: domain,channel event.
 363  *
 364  * Returns zero if the element's value could be written.
 365  * Negative values indicate an error.
 366  */
 367 int mi_lttng_session(struct mi_writer *writer,
 368                 struct lttng_session *session, int is_open);
 369
 370 /*
 371  * Machine interface: open a domains element.
 372  *
 373  * writer An instance of a machine interface writer.
 374  *
 375  * Returns zero if the element's value could be written.
 376  * Negative values indicate an error.
 377  */
 378 int mi_lttng_domains_open(struct mi_writer *writer);
 379
 380 /*
 381  * Machine interface of struct domain.
 382  *
 383  * writer An instance of a machine interface writer.
 384  * domain An instance of a domain.
 385  *
 386  * is_open Defines whether or not the session element shall be closed.
 387  *         This should be used carefully and the client
 388  *         must close the domain element.
 389  *         Use case: nested addition information on a domain
 390  *                  ex: channel event.
 391  *
 392  * Returns zero if the element's value could be written.
 393  * Negative values indicate an error.
 394  */
 395 int mi_lttng_domain(struct mi_writer *writer,
 396                 struct lttng_domain *domain, int is_open);
 397
 398 /*
 399  * Machine interface: open a channels element.
 400  *
 401  * writer An instance of a machine interface writer.
 402  *
 403  * Returns zero if the element's value could be written.
 404  * Negative values indicate an error.
 405  */
 406 int mi_lttng_channels_open(struct mi_writer *writer);
 407
 408 /*
 409  * Machine interface of struct channel.
 410  *
 411  * writer An instance of a machine interface writer.
 412  * channel An instance of a channel.
 413  *
 414  * is_open Defines whether or not the session element shall be closed.
 415  *         This should be used carefully and the client
 416  *         must close the channel element.
 417  *         Use case: nested addition information on a channel.
 418  *                  ex: channel event.
 419  *
 420  * Returns zero if the element's value could be written.
 421  * Negative values indicate an error.
 422  */
 423 int mi_lttng_channel(struct mi_writer *writer,
 424                 struct lttng_channel *channel, int is_open);
 425
 426 /*
 427  * Machine interface of struct channel_attr.
 428  *
 429  * writer An instance of a machine interface writer.
 430  * attr An instance of a channel_attr struct.
 431  *
 432  * Returns zero if the element's value could be written.
 433  * Negative values indicate an error.
 434  */
 435 int mi_lttng_channel_attr(struct mi_writer *writer,
 436                 struct lttng_channel_attr *attr);
 437
 438 /*
 439 * Machine interface for event common attributes.
 440 *
 441 * writer An instance of a mi writer.
 442 * event single trace event.
 443 *
 444 * The common attribute are:
 445 * - mi event element
 446 * - event name
 447 * - event type
 448 * - enabled tag
 449 * - event filter
 450 *
 451 * Returns zero if the element's value could be written.
 452 * Negative values indicate an error.
 453 */
 454 int mi_lttng_event_common_attributes(struct mi_writer *writer,
 455                 struct lttng_event *event);
 456
 457 /*
 458  * Machine interface for kernel tracepoint event with a loglevel.
 459  *
 460  * writer An instance of a mi writer.
 461  * event single trace event.
 462  * domain Event's domain
 463  *
 464  * Returns zero if the element's value could be written.
 465  * Negative values indicate an error.
 466  */
 467 int mi_lttng_event_tracepoint_loglevel(struct mi_writer *writer,
 468                 struct lttng_event *event, enum lttng_domain_type domain);
 469
 470 /*
 471  * Machine interface for kernel tracepoint event with no loglevel.
 472  *
 473  * writer An instance of a mi writer.
 474  * event single trace event.
 475  *
 476  * Returns zero if the element's value could be written.
 477  * Negative values indicate an error.
 478  */
 479 int mi_lttng_event_tracepoint_no_loglevel(struct mi_writer *writer,
 480                 struct lttng_event *event);
 481
 482 /*
 483  * Machine interface for kernel function and probe event.
 484  *
 485  * writer An instance of a mi writer.
 486  * event single trace event.
 487  *
 488  * Returns zero if the element's value could be written.
 489  * Negative values indicate an error.
 490  */
 491 int mi_lttng_event_function_probe(struct mi_writer *writer,
 492                 struct lttng_event *event);
 493
 494 /*
 495  * Machine interface for kernel function entry event.
 496  *
 497  * writer An instance of a mi writer.
 498  * event single trace event.
 499  *
 500  * Returns zero if the element's value could be written.
 501  * Negative values indicate an error.
 502  */
 503 int mi_lttng_event_function_entry(struct mi_writer *writer,
 504                 struct lttng_event *event);
 505
 506 /*
 507  * Machine interface: open an events element.
 508  *
 509  * writer An instance of a machine interface writer.
 510  *
 511  * Returns zero if the element's value could be written.
 512  * Negative values indicate an error.
 513  */
 514 int mi_lttng_events_open(struct mi_writer *writer);
 515
 516 /*
 517  * Machine interface for printing an event.
 518  * The trace event type currently supported are:
 519  *  TRACEPOINT,
 520  *  PROBE,
 521  *  FUNCTION,
 522  *  FUNCTION_ENTRY,
 523  *  SYSCALL
 524  *
 525  * writer An instance of a mi writer.
 526  * event single trace event.
 527  * is_open Defines whether or not the session element shall be closed.
 528  *         This should be used carefully and the client
 529  *         must close the event element.
 530  *         Use case: nested additional information
 531  * domain Event's domain
 532  *
 533  * Returns zero if the element's value could be written.
 534  * Negative values indicate an error.
 535  */
 536 int mi_lttng_event(struct mi_writer *writer, struct lttng_event *event,
 537                 int is_open, enum lttng_domain_type domain);
 538
 539 /*
 540  * Machine interface for struct lttng_event_field.
 541  *
 542  * writer An instance of a mi writer.
 543  * field An event_field instance.
 544  *
 545  * Returns zero if the element's value could be written.
 546  * Negative values indicate an error.
 547  */
 548 int mi_lttng_event_field(struct mi_writer *writer,
 549                 struct lttng_event_field *field);
 550
 551 /*
 552  * Machine interface: open a event_fields element.
 553  *
 554  * writer An instance of a machine interface writer.
 555  *
 556  * Returns zero if the element have be written.
 557  * Negative values indicate an error.
 558  */
 559 int mi_lttng_event_fields_open(struct mi_writer *writer);
 560
 561 /*
 562  * Machine interface: open a trackers element.
 563  *
 564  * writer An instance of a machine interface writer.
 565  *
 566  * Returns zero if the element's value could be written.
 567  * Negative values indicate an error.
 568  */
 569 int mi_lttng_trackers_open(struct mi_writer *writer);
 570
 571 /*
 572  * Machine interface: open a pid_tracker element.
 573  *
 574  * writer An instance of a machine interface writer.
 575  *
 576  * Returns zero if the element's value could be written.
 577  * Negative values indicate an error.
 578  *
 579  * Note: A targets element is also opened for each tracker definition
 580  */
 581 int mi_lttng_pid_tracker_open(struct mi_writer *writer);
 582
 583 /*
 584  * Machine interface: open a PIDs element.
 585  *
 586  * writer An instance of a machine interface writer.
 587  *
 588  * Returns zero if the element's value could be written.
 589  * Negative values indicate an error.
 590  */
 591 int mi_lttng_pids_open(struct mi_writer *writer);
 592
 593 /*
 594  * Machine interface: open a processes element.
 595  *
 596  * writer An instance of a machine interface writer.
 597  *
 598  * Returns zero if the element's value could be written.
 599  * Negative values indicate an error.
 600  */
 601 int mi_lttng_processes_open(struct mi_writer *writer);
 602
 603 /*
 604  * Machine interface of a Process.
 605  *
 606  * writer An instance of a machine interface writer.
 607  * pid A PID.
 608  *
 609  * is_open Defines whether or not the session element shall be closed.
 610  *         This should be used carefully and the client
 611  *         must close the pid element.
 612  *         Use case: nested addition information on a domain
 613  *                  ex: channel event.
 614  *
 615  * Returns zero if the element's value could be written.
 616  * Negative values indicate an error.
 617  */
 618 int mi_lttng_process(struct mi_writer *writer, pid_t pid , const char *name,
 619                 int is_open);
 620 /*
 621  * Machine interface: open a targets element.
 622  *
 623  * writer An instance of a machine interface writer.
 624  *
 625  * Returns zero if the element's value could be written.
 626  * Negative values indicate an error.
 627  */
 628 int mi_lttng_targets_open(struct mi_writer *writer);
 629
 630 /*
 631  * Machine interface for track/untrack a pid_target
 632  *
 633  * writer An instance of a machine interface writer.
 634  *
 635  * Returns zero if the element's value could be written.
 636  * Negative values indicate an error.
 637  */
 638 int mi_lttng_pid_target(struct mi_writer *writer, pid_t pid, int is_open);
 639
 640 /*
 641  * Machine interface for struct lttng_calibrate.
 642  *
 643  * writer An instance of a machine interface writer.
 644  *
 645  * calibrate A lttng_calibrate instance.
 646  *
 647  * Returns zero if the element's value could be written.
 648  * Negative values indicate an error.
 649  */
 650 int mi_lttng_calibrate(struct mi_writer *writer,
 651                 struct lttng_calibrate *calibrate);
 652
 653 /*
 654  * Machine interface of a context.
 655  *
 656  * writer An instance of a machine interface writer
 657  *
 658  * context An instance of a lttng_event_context
 659  *
 660  * is_open Define if we close the context element
 661  *         This should be used carefully and the client
 662  *         need to close the context element.
 663  * Returns zero if the element's value could be written.
 664  * Negative values indicate an error.
 665  */
 666 int mi_lttng_context(struct mi_writer *writer,
 667                 struct lttng_event_context *context, int is_open);
 668
 669 /*
 670  * Machine interface of a perf_counter_context.
 671  *
 672  * writer An instance of a machine interface writer
 673  *
 674  * contest An instance of a lttng_event_perf_counter_ctx
 675  *
 676  * Returns zero if the element's value could be written.
 677  * Negative values indicate an error.
 678  */
 679 int mi_lttng_perf_counter_context(struct mi_writer *writer,
 680                 struct lttng_event_perf_counter_ctx  *perf_context);
 681
 682 /*
 683  * Machine interface of the snapshot list_output.
 684  * It specifies the session for which we are listing snapshots,
 685  * and it opens a snapshots element to list a sequence
 686  * of snapshots.
 687  *
 688  * writer An instance of a machine interface writer.
 689  *
 690  * session_name: Snapshot output for session "session_name".
 691  *
 692  * Note: The client has to close the session and the snapshots elements after
 693  * having listed every lttng_snapshot_output.
 694  *
 695  * Returns zero if the element's value could be written.
 696  * Negative values indicate an error.
 697  */
 698 int mi_lttng_snapshot_output_session_name(struct mi_writer *writer,
 699                 const char *session_name);
 700
 701 /*
 702  * Machine interface of the snapshot output.
 703  * The machine interface serializes the following attributes:
 704  * - id: ID of the snapshot output.
 705  * - name: Name of the output.
 706  * - data_url : Destination of the output.
 707  * - ctrl_url: Destination of the output.
 708  * - max_size: total size of all stream combined.
 709  *
 710  * writer An instance of a machine interface writer.
 711  *
 712  * output: A list of snapshot_output.
 713  *
 714  * Returns zero if the element's value could be written.
 715  * Negative values indicate an error.
 716  */
 717 int mi_lttng_snapshot_list_output(struct mi_writer *writer,
 718                 struct lttng_snapshot_output *output);
 719
 720 /*
 721  * Machine interface of the output of the command snapshot del output
 722  * when deleting a snapshot either by id or by name.
 723  * If the snapshot was found and successfully deleted using its id,
 724  * it return the id of the snapshot and the current session name on which it
 725  * was attached.
 726  *
 727  * Otherwise, it do the same process with the name of the snapshot, if the
 728  * snapshot output id is undefined.
 729  *
 730  * writer An instance of a machine interface writer.
 731  *
 732  * id: ID of the snapshot output.
 733  *
 734  * name: Name of the snapshot.
 735  *
 736  * current_session_name: Session to which the snapshot belongs.
 737  *
 738  * Returns zero if the element's value could be written.
 739  * Negative values indicate an error.
 740  */
 741 int mi_lttng_snapshot_del_output(struct mi_writer *writer, int id,
 742                 const char *name, const char *current_session_name);
 743
 744 /*
 745  * Machine interface of the output of the command snapshot add output
 746  * when adding a snapshot from a user URL.
 747  *
 748  * If the snapshot was successfully added, the machine interface lists
 749  * these information:
 750  * - id: ID of the newly add snapshot output.
 751  * - current_session_name: Name of the session to which the output was added.
 752  * - ctrl_url: Destination of the output.
 753  * - max_size: total size of all stream combined.
 754  *
 755  * writer An instance of a machine interface writer.
 756  *
 757  * current_session_name: Session to which the snapshot belongs.
 758  *
 759  * n_ptr:
 760  *
 761  * output: iterator over a lttng_snapshot_output_list which contain
 762  * the snapshot output informations.
 763  *
 764  * Returns zero if the element's value could be written.
 765  * Negative values indicate an error.
 766  */
 767 int mi_lttng_snapshot_add_output(struct mi_writer *writer,
 768                 const char *current_session_name, const char *n_ptr,
 769                 struct lttng_snapshot_output *output);
 770
 771 /*
 772  * Machine interface of the output of the command snapshot
 773  * record  from a URL (if given).
 774  *
 775  * If the snapshot is successfully recorded from a url, the machine interface
 776  * output the following information:
 777  * - url: Destination of the output stored in the snapshot.
 778  *
 779  * Otherwise, the machine interface output the data and ctrl url received
 780  * from the command-line.
 781  *
 782  * writer An instance of a machine interface writer.
 783  *
 784  * current_session_name: Snapshot record for session "current_session_name".
 785  *
 786  * ctrl_url, data_url: Destination of the output receive from the command-line.
 787  *
 788  * Returns zero if the element's value could be written.
 789  * Negative values indicate an error.
 790  */
 791 int mi_lttng_snapshot_record(struct mi_writer *writer,
 792                 const char *current_session_name, const char *url,
 793                 const char *cmdline_ctrl_url, const char *cmdline_data_url);
 794
 795 #endif /* _MI_LTTNG_H */