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>
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.
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
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.
25 #include <common/error.h>
26 #include <common/macros.h>
27 #include <common/config/session-config.h>
28 #include <lttng/lttng.h>
30 /* Don't want to reference snapshot-internal.h here */
31 struct lttng_snapshot_output
;
33 /* Instance of a machine interface writer. */
35 struct config_writer
*writer
;
36 enum lttng_mi_output_type type
;
40 * Version information for the machine interface.
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. */
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
;
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
;
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
;
99 /* String related to lttng_event_perf_counter_ctx */
100 extern const char * const mi_lttng_element_perf_counter_context
;
102 /* Strings related to pid */
103 extern const char * const mi_lttng_element_pid_id
;
105 /* Strings related to save command */
106 extern const char * const mi_lttng_element_save
;
108 /* Strings related to load command */
109 extern const char * const mi_lttng_element_load
;
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
;
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
;
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
;
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
;
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
;
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
;
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
;
183 /* String related to track/untrack command */
184 const char * const mi_lttng_element_track_untrack_all_wildcard
;
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
);
194 * Create an instance of a machine interface writer.
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.
199 * Returns an instance of a machine interface writer on success, NULL on
202 struct mi_writer
*mi_lttng_writer_create(int fd_output
, int mi_output_type
);
205 * Destroy an instance of a machine interface writer.
207 * writer An instance of a machine interface writer.
209 * Returns zero if the XML document could be closed cleanly. Negative values
212 int mi_lttng_writer_destroy(struct mi_writer
*writer
);
215 * Open a command tag and add it's name node.
217 * writer An instance of a machine interface writer.
218 * command The command name.
220 * Returns zero if the XML document could be closed cleanly.
221 * Negative values indicate an error.
223 int mi_lttng_writer_command_open(struct mi_writer
*writer
, const char *command
);
226 * Close a command tag.
228 * writer An instance of a machine interface writer.
230 * Returns zero if the XML document could be closed cleanly.
231 * Negative values indicate an error.
233 int mi_lttng_writer_command_close(struct mi_writer
*writer
);
236 * Open an element tag.
238 * writer An instance of a machine interface writer.
239 * element_name Element tag name.
241 * Returns zero if the XML document could be closed cleanly.
242 * Negative values indicate an error.
244 int mi_lttng_writer_open_element(struct mi_writer
*writer
,
245 const char *element_name
);
248 * Close the current element tag.
250 * writer An instance of a machine interface writer.
252 * Returns zero if the XML document could be closed cleanly.
253 * Negative values indicate an error.
255 int mi_lttng_writer_close_element(struct mi_writer
*writer
);
258 * Close multiple element.
260 * writer An instance of a machine interface writer.
261 * nb_element Number of elements.
263 * Returns zero if the XML document could be closed cleanly.
264 * Negative values indicate an error.
266 int mi_lttng_close_multi_element(struct mi_writer
*writer
,
267 unsigned int nb_element
);
270 * Write an element of type unsigned int.
272 * writer An instance of a machine interface writer.
273 * element_name Element name.
274 * value Unsigned int value of the element
276 * Returns zero if the element's value could be written.
277 * Negative values indicate an error.
279 int mi_lttng_writer_write_element_unsigned_int(struct mi_writer
*writer
,
280 const char *element_name
, uint64_t value
);
283 * Write an element of type signed int.
285 * writer An instance of a machine interface writer.
286 * element_name Element name.
287 * value Signed int value of the element.
289 * Returns zero if the element's value could be written.
290 * Negative values indicate an error.
292 int mi_lttng_writer_write_element_signed_int(struct mi_writer
*writer
,
293 const char *element_name
, int64_t value
);
296 * Write an element of type boolean.
298 * writer An instance of a machine interface writer.
299 * element_name Element name.
300 * value Boolean value of the element.
302 * Returns zero if the element's value could be written.
303 * Negative values indicate an error.
305 int mi_lttng_writer_write_element_bool(struct mi_writer
*writer
,
306 const char *element_name
, int value
);
309 * Write an element of type string.
311 * writer An instance of a machine interface writer.
312 * element_name Element name.
313 * value String value of the element.
315 * Returns zero if the element's value could be written.
316 * Negative values indicate an error.
318 int mi_lttng_writer_write_element_string(struct mi_writer
*writer
,
319 const char *element_name
, const char *value
);
322 * Machine interface of struct version.
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.
329 * Returns zero if the element's value could be written.
330 * Negative values indicate an error.
332 int mi_lttng_version(struct mi_writer
*writer
, struct mi_lttng_version
*version
,
333 const char *lttng_description
, const char *lttng_license
);
336 * Machine interface: open a sessions element.
338 * writer An instance of a machine interface writer.
340 * Returns zero if the element's value could be written.
341 * Negative values indicate an error.
343 int mi_lttng_sessions_open(struct mi_writer
*writer
);
346 * Machine interface of struct session.
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.
356 * Returns zero if the element's value could be written.
357 * Negative values indicate an error.
359 int mi_lttng_session(struct mi_writer
*writer
,
360 struct lttng_session
*session
, int is_open
);
363 * Machine interface: open a domains element.
365 * writer An instance of a machine interface writer.
367 * Returns zero if the element's value could be written.
368 * Negative values indicate an error.
370 int mi_lttng_domains_open(struct mi_writer
*writer
);
373 * Machine interface of struct domain.
375 * writer An instance of a machine interface writer.
376 * domain An instance of a domain.
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
384 * Returns zero if the element's value could be written.
385 * Negative values indicate an error.
387 int mi_lttng_domain(struct mi_writer
*writer
,
388 struct lttng_domain
*domain
, int is_open
);
391 * Machine interface: open a channels element.
393 * writer An instance of a machine interface writer.
395 * Returns zero if the element's value could be written.
396 * Negative values indicate an error.
398 int mi_lttng_channels_open(struct mi_writer
*writer
);
401 * Machine interface of struct channel.
403 * writer An instance of a machine interface writer.
404 * channel An instance of a channel.
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.
412 * Returns zero if the element's value could be written.
413 * Negative values indicate an error.
415 int mi_lttng_channel(struct mi_writer
*writer
,
416 struct lttng_channel
*channel
, int is_open
);
419 * Machine interface of struct channel_attr.
421 * writer An instance of a machine interface writer.
422 * attr An instance of a channel_attr struct.
424 * Returns zero if the element's value could be written.
425 * Negative values indicate an error.
427 int mi_lttng_channel_attr(struct mi_writer
*writer
,
428 struct lttng_channel_attr
*attr
);
431 * Machine interface for event common attributes.
433 * writer An instance of a mi writer.
434 * event single trace event.
436 * The common attribute are:
443 * Returns zero if the element's value could be written.
444 * Negative values indicate an error.
446 int mi_lttng_event_common_attributes(struct mi_writer
*writer
,
447 struct lttng_event
*event
);
450 * Machine interface for kernel tracepoint event with a loglevel.
452 * writer An instance of a mi writer.
453 * event single trace event.
454 * domain Event's domain
456 * Returns zero if the element's value could be written.
457 * Negative values indicate an error.
459 int mi_lttng_event_tracepoint_loglevel(struct mi_writer
*writer
,
460 struct lttng_event
*event
, enum lttng_domain_type domain
);
463 * Machine interface for kernel tracepoint event with no loglevel.
465 * writer An instance of a mi writer.
466 * event single trace event.
468 * Returns zero if the element's value could be written.
469 * Negative values indicate an error.
471 int mi_lttng_event_tracepoint_no_loglevel(struct mi_writer
*writer
,
472 struct lttng_event
*event
);
475 * Machine interface for kernel function and probe event.
477 * writer An instance of a mi writer.
478 * event single trace event.
480 * Returns zero if the element's value could be written.
481 * Negative values indicate an error.
483 int mi_lttng_event_function_probe(struct mi_writer
*writer
,
484 struct lttng_event
*event
);
487 * Machine interface for kernel function entry event.
489 * writer An instance of a mi writer.
490 * event single trace event.
492 * Returns zero if the element's value could be written.
493 * Negative values indicate an error.
495 int mi_lttng_event_function_entry(struct mi_writer
*writer
,
496 struct lttng_event
*event
);
499 * Machine interface: open an events element.
501 * writer An instance of a machine interface writer.
503 * Returns zero if the element's value could be written.
504 * Negative values indicate an error.
506 int mi_lttng_events_open(struct mi_writer
*writer
);
509 * Machine interface for printing an event.
510 * The trace event type currently supported are:
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
525 * Returns zero if the element's value could be written.
526 * Negative values indicate an error.
528 int mi_lttng_event(struct mi_writer
*writer
, struct lttng_event
*event
,
529 int is_open
, enum lttng_domain_type domain
);
532 * Machine interface for struct lttng_event_field.
534 * writer An instance of a mi writer.
535 * field An event_field instance.
537 * Returns zero if the element's value could be written.
538 * Negative values indicate an error.
540 int mi_lttng_event_field(struct mi_writer
*writer
,
541 struct lttng_event_field
*field
);
544 * Machine interface: open a event_fields element.
546 * writer An instance of a machine interface writer.
548 * Returns zero if the element have be written.
549 * Negative values indicate an error.
551 int mi_lttng_event_fields_open(struct mi_writer
*writer
);
554 * Machine interface: open a trackers element.
556 * writer An instance of a machine interface writer.
558 * Returns zero if the element's value could be written.
559 * Negative values indicate an error.
561 int mi_lttng_trackers_open(struct mi_writer
*writer
);
564 * Machine interface: open a pid_tracker element.
566 * writer An instance of a machine interface writer.
568 * Returns zero if the element's value could be written.
569 * Negative values indicate an error.
571 * Note: A targets element is also opened for each tracker definition
573 int mi_lttng_pid_tracker_open(struct mi_writer
*writer
);
576 * Machine interface: open a PIDs element.
578 * writer An instance of a machine interface writer.
580 * Returns zero if the element's value could be written.
581 * Negative values indicate an error.
583 int mi_lttng_pids_open(struct mi_writer
*writer
);
586 * Machine interface: open a processes element.
588 * writer An instance of a machine interface writer.
590 * Returns zero if the element's value could be written.
591 * Negative values indicate an error.
593 int mi_lttng_processes_open(struct mi_writer
*writer
);
596 * Machine interface of a Process.
598 * writer An instance of a machine interface writer.
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
607 * Returns zero if the element's value could be written.
608 * Negative values indicate an error.
610 int mi_lttng_process(struct mi_writer
*writer
, pid_t pid
, const char *name
,
614 * TODO: move pid of lttng list -u to process semantic on mi api bump
615 * Machine interface of a Process.
617 * writer An instance of a machine interface writer.
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
626 * Returns zero if the element's value could be written.
627 * Negative values indicate an error.
629 int mi_lttng_pid(struct mi_writer
*writer
, pid_t pid
, const char *name
,
632 * Machine interface: open a targets element.
634 * writer An instance of a machine interface writer.
636 * Returns zero if the element's value could be written.
637 * Negative values indicate an error.
639 int mi_lttng_targets_open(struct mi_writer
*writer
);
642 * Machine interface for track/untrack a pid_target
644 * writer An instance of a machine interface writer.
646 * Returns zero if the element's value could be written.
647 * Negative values indicate an error.
649 int mi_lttng_pid_target(struct mi_writer
*writer
, pid_t pid
, int is_open
);
652 * Machine interface of a context.
654 * writer An instance of a machine interface writer
656 * context An instance of a lttng_event_context
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.
664 int mi_lttng_context(struct mi_writer
*writer
,
665 struct lttng_event_context
*context
, int is_open
);
668 * Machine interface of a perf_counter_context.
670 * writer An instance of a machine interface writer
672 * contest An instance of a lttng_event_perf_counter_ctx
674 * Returns zero if the element's value could be written.
675 * Negative values indicate an error.
677 int mi_lttng_perf_counter_context(struct mi_writer
*writer
,
678 struct lttng_event_perf_counter_ctx
*perf_context
);
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
686 * writer An instance of a machine interface writer.
688 * session_name: Snapshot output for session "session_name".
690 * Note: The client has to close the session and the snapshots elements after
691 * having listed every lttng_snapshot_output.
693 * Returns zero if the element's value could be written.
694 * Negative values indicate an error.
696 int mi_lttng_snapshot_output_session_name(struct mi_writer
*writer
,
697 const char *session_name
);
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.
708 * writer An instance of a machine interface writer.
710 * output: A list of snapshot_output.
712 * Returns zero if the element's value could be written.
713 * Negative values indicate an error.
715 int mi_lttng_snapshot_list_output(struct mi_writer
*writer
,
716 struct lttng_snapshot_output
*output
);
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
725 * Otherwise, it do the same process with the name of the snapshot, if the
726 * snapshot output id is undefined.
728 * writer An instance of a machine interface writer.
730 * id: ID of the snapshot output.
732 * name: Name of the snapshot.
734 * current_session_name: Session to which the snapshot belongs.
736 * Returns zero if the element's value could be written.
737 * Negative values indicate an error.
739 int mi_lttng_snapshot_del_output(struct mi_writer
*writer
, int id
,
740 const char *name
, const char *current_session_name
);
743 * Machine interface of the output of the command snapshot add output
744 * when adding a snapshot from a user URL.
746 * If the snapshot was successfully added, the machine interface lists
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.
753 * writer An instance of a machine interface writer.
755 * current_session_name: Session to which the snapshot belongs.
759 * output: iterator over a lttng_snapshot_output_list which contain
760 * the snapshot output informations.
762 * Returns zero if the element's value could be written.
763 * Negative values indicate an error.
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
);
770 * Machine interface of the output of the command snapshot
771 * record from a URL (if given).
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.
777 * Otherwise, the machine interface output the data and ctrl url received
778 * from the command-line.
780 * writer An instance of a machine interface writer.
782 * current_session_name: Snapshot record for session "current_session_name".
784 * ctrl_url, data_url: Destination of the output receive from the command-line.
786 * Returns zero if the element's value could be written.
787 * Negative values indicate an error.
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
);
793 #endif /* _MI_LTTNG_H */