2 * Copyright (C) 2014 - Jonathan Rajotte <jonathan.r.julien@gmail.com>
3 * - Olivier Cotte <olivier.cotte@polymtl.ca>
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.
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
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.
24 #include <common/error.h>
25 #include <common/macros.h>
26 #include <common/config/config.h>
27 #include <lttng/lttng.h>
29 /* Don't want to reference snapshot-internal.h here */
30 struct lttng_snapshot_output
;
32 /* Instance of a machine interface writer. */
34 struct config_writer
*writer
;
35 enum lttng_mi_output_type type
;
39 * Version information for the machine interface.
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. */
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
;
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
;
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
;
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
;
100 /* String related to lttng_event_perf_counter_ctx */
101 extern const char * const mi_lttng_element_perf_counter_context
;
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
;
108 /* Strings related to save command */
109 extern const char * const mi_lttng_element_save
;
111 /* Strings related to load command */
112 extern const char * const mi_lttng_element_load
;
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
;
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
;
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
;
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
;
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
;
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
;
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
;
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
;
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
);
198 /* String related to track/untrack command */
199 const char * const mi_lttng_element_track_untrack_targets
;
200 const char * const mi_lttng_element_track_untrack_pid_target
;
201 const char * const mi_lttng_element_track_untrack_all_wildcard
;
204 * Create an instance of a machine interface writer.
206 * fd_output File to which the XML content must be written. The file will be
207 * closed once the mi_writer has been destroyed.
209 * Returns an instance of a machine interface writer on success, NULL on
212 struct mi_writer
*mi_lttng_writer_create(int fd_output
, int mi_output_type
);
215 * Destroy an instance of a machine interface writer.
217 * writer An instance of a machine interface writer.
219 * Returns zero if the XML document could be closed cleanly. Negative values
222 int mi_lttng_writer_destroy(struct mi_writer
*writer
);
225 * Open a command tag and add it's name node.
227 * writer An instance of a machine interface writer.
228 * command The command name.
230 * Returns zero if the XML document could be closed cleanly.
231 * Negative values indicate an error.
233 int mi_lttng_writer_command_open(struct mi_writer
*writer
, const char *command
);
236 * Close a command tag.
238 * writer An instance of a machine interface writer.
240 * Returns zero if the XML document could be closed cleanly.
241 * Negative values indicate an error.
243 int mi_lttng_writer_command_close(struct mi_writer
*writer
);
246 * Open an element tag.
248 * writer An instance of a machine interface writer.
249 * element_name Element tag name.
251 * Returns zero if the XML document could be closed cleanly.
252 * Negative values indicate an error.
254 int mi_lttng_writer_open_element(struct mi_writer
*writer
,
255 const char *element_name
);
258 * Close the current element tag.
260 * writer An instance of a machine interface writer.
262 * Returns zero if the XML document could be closed cleanly.
263 * Negative values indicate an error.
265 int mi_lttng_writer_close_element(struct mi_writer
*writer
);
268 * Close multiple element.
270 * writer An instance of a machine interface writer.
271 * nb_element Number of elements.
273 * Returns zero if the XML document could be closed cleanly.
274 * Negative values indicate an error.
276 int mi_lttng_close_multi_element(struct mi_writer
*writer
,
277 unsigned int nb_element
);
280 * Write an element of type unsigned int.
282 * writer An instance of a machine interface writer.
283 * element_name Element name.
284 * value Unsigned int value of the element
286 * Returns zero if the element's value could be written.
287 * Negative values indicate an error.
289 int mi_lttng_writer_write_element_unsigned_int(struct mi_writer
*writer
,
290 const char *element_name
, uint64_t value
);
293 * Write an element of type signed int.
295 * writer An instance of a machine interface writer.
296 * element_name Element name.
297 * value Signed int value of the element.
299 * Returns zero if the element's value could be written.
300 * Negative values indicate an error.
302 int mi_lttng_writer_write_element_signed_int(struct mi_writer
*writer
,
303 const char *element_name
, int64_t value
);
306 * Write an element of type boolean.
308 * writer An instance of a machine interface writer.
309 * element_name Element name.
310 * value Boolean value of the element.
312 * Returns zero if the element's value could be written.
313 * Negative values indicate an error.
315 int mi_lttng_writer_write_element_bool(struct mi_writer
*writer
,
316 const char *element_name
, int value
);
319 * Write an element of type string.
321 * writer An instance of a machine interface writer.
322 * element_name Element name.
323 * value String value of the element.
325 * Returns zero if the element's value could be written.
326 * Negative values indicate an error.
328 int mi_lttng_writer_write_element_string(struct mi_writer
*writer
,
329 const char *element_name
, const char *value
);
332 * Machine interface of struct version.
334 * writer An instance of a machine interface writer.
335 * version Version struct.
336 * lttng_description String value of the version description.
337 * lttng_license String value of the version license.
339 * Returns zero if the element's value could be written.
340 * Negative values indicate an error.
342 int mi_lttng_version(struct mi_writer
*writer
, struct mi_lttng_version
*version
,
343 const char *lttng_description
, const char *lttng_license
);
346 * Machine interface: open a sessions element.
348 * writer An instance of a machine interface writer.
350 * Returns zero if the element's value could be written.
351 * Negative values indicate an error.
353 int mi_lttng_sessions_open(struct mi_writer
*writer
);
356 * Machine interface of struct session.
358 * writer An instance of a machine interface writer.
359 * session An instance of a session.
360 * is_open Defines whether or not the session element shall be closed.
361 * This should be used carefully and the client
362 * must close the session element.
363 * Use case: nested additional information on a session
364 * ex: domain,channel event.
366 * Returns zero if the element's value could be written.
367 * Negative values indicate an error.
369 int mi_lttng_session(struct mi_writer
*writer
,
370 struct lttng_session
*session
, int is_open
);
373 * Machine interface: open a domains element.
375 * writer An instance of a machine interface writer.
377 * Returns zero if the element's value could be written.
378 * Negative values indicate an error.
380 int mi_lttng_domains_open(struct mi_writer
*writer
);
383 * Machine interface of struct domain.
385 * writer An instance of a machine interface writer.
386 * domain An instance of a domain.
388 * is_open Defines whether or not the session element shall be closed.
389 * This should be used carefully and the client
390 * must close the domain element.
391 * Use case: nested addition information on a domain
394 * Returns zero if the element's value could be written.
395 * Negative values indicate an error.
397 int mi_lttng_domain(struct mi_writer
*writer
,
398 struct lttng_domain
*domain
, int is_open
);
401 * Machine interface: open a channels element.
403 * writer An instance of a machine interface writer.
405 * Returns zero if the element's value could be written.
406 * Negative values indicate an error.
408 int mi_lttng_channels_open(struct mi_writer
*writer
);
411 * Machine interface of struct channel.
413 * writer An instance of a machine interface writer.
414 * channel An instance of a channel.
416 * is_open Defines whether or not the session element shall be closed.
417 * This should be used carefully and the client
418 * must close the channel element.
419 * Use case: nested addition information on a channel.
422 * Returns zero if the element's value could be written.
423 * Negative values indicate an error.
425 int mi_lttng_channel(struct mi_writer
*writer
,
426 struct lttng_channel
*channel
, int is_open
);
429 * Machine interface of struct channel_attr.
431 * writer An instance of a machine interface writer.
432 * attr An instance of a channel_attr struct.
434 * Returns zero if the element's value could be written.
435 * Negative values indicate an error.
437 int mi_lttng_channel_attr(struct mi_writer
*writer
,
438 struct lttng_channel_attr
*attr
);
441 * Machine interface for event common attributes.
443 * writer An instance of a mi writer.
444 * event single trace event.
446 * The common attribute are:
453 * Returns zero if the element's value could be written.
454 * Negative values indicate an error.
456 int mi_lttng_event_common_attributes(struct mi_writer
*writer
,
457 struct lttng_event
*event
);
460 * Machine interface for kernel tracepoint event with a loglevel.
462 * writer An instance of a mi writer.
463 * event single trace event.
464 * domain Event's domain
466 * Returns zero if the element's value could be written.
467 * Negative values indicate an error.
469 int mi_lttng_event_tracepoint_loglevel(struct mi_writer
*writer
,
470 struct lttng_event
*event
, enum lttng_domain_type domain
);
473 * Machine interface for kernel tracepoint event with no loglevel.
475 * writer An instance of a mi writer.
476 * event single trace event.
478 * Returns zero if the element's value could be written.
479 * Negative values indicate an error.
481 int mi_lttng_event_tracepoint_no_loglevel(struct mi_writer
*writer
,
482 struct lttng_event
*event
);
485 * Machine interface for kernel function and probe event.
487 * writer An instance of a mi writer.
488 * event single trace event.
490 * Returns zero if the element's value could be written.
491 * Negative values indicate an error.
493 int mi_lttng_event_function_probe(struct mi_writer
*writer
,
494 struct lttng_event
*event
);
497 * Machine interface for kernel function entry event.
499 * writer An instance of a mi writer.
500 * event single trace event.
502 * Returns zero if the element's value could be written.
503 * Negative values indicate an error.
505 int mi_lttng_event_function_entry(struct mi_writer
*writer
,
506 struct lttng_event
*event
);
509 * Machine interface: open an events element.
511 * writer An instance of a machine interface writer.
513 * Returns zero if the element's value could be written.
514 * Negative values indicate an error.
516 int mi_lttng_events_open(struct mi_writer
*writer
);
519 * Machine interface for printing an event.
520 * The trace event type currently supported are:
527 * writer An instance of a mi writer.
528 * event single trace event.
529 * is_open Defines whether or not the session element shall be closed.
530 * This should be used carefully and the client
531 * must close the event element.
532 * Use case: nested additional information
533 * domain Event's domain
535 * Returns zero if the element's value could be written.
536 * Negative values indicate an error.
538 int mi_lttng_event(struct mi_writer
*writer
, struct lttng_event
*event
,
539 int is_open
, enum lttng_domain_type domain
);
542 * Machine interface for struct lttng_event_field.
544 * writer An instance of a mi writer.
545 * field An event_field instance.
547 * Returns zero if the element's value could be written.
548 * Negative values indicate an error.
550 int mi_lttng_event_field(struct mi_writer
*writer
,
551 struct lttng_event_field
*field
);
554 * Machine interface: open a event_fields element.
556 * writer An instance of a machine interface writer.
558 * Returns zero if the element have be written.
559 * Negative values indicate an error.
561 int mi_lttng_event_fields_open(struct mi_writer
*writer
);
564 * Machine interface: open a trackers 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 int mi_lttng_trackers_open(struct mi_writer
*writer
);
574 * Machine interface: open a pid_tracker element.
576 * writer An instance of a machine interface writer.
578 * Returns zero if the element's value could be written.
579 * Negative values indicate an error.
581 * Note: A targets element is also opened for each tracker definition
583 int mi_lttng_pid_tracker_open(struct mi_writer
*writer
);
586 * Machine interface: open a PIDs 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_pids_open(struct mi_writer
*writer
);
596 * Machine interface: open a processes element.
598 * writer An instance of a machine interface writer.
600 * Returns zero if the element's value could be written.
601 * Negative values indicate an error.
603 int mi_lttng_processes_open(struct mi_writer
*writer
);
606 * Machine interface of a Process.
608 * writer An instance of a machine interface writer.
611 * is_open Defines whether or not the session element shall be closed.
612 * This should be used carefully and the client
613 * must close the pid element.
614 * Use case: nested addition information on a domain
617 * Returns zero if the element's value could be written.
618 * Negative values indicate an error.
620 int mi_lttng_process(struct mi_writer
*writer
, pid_t pid
, const char *name
,
623 * Machine interface: open a targets element.
625 * writer An instance of a machine interface writer.
627 * Returns zero if the element's value could be written.
628 * Negative values indicate an error.
630 int mi_lttng_targets_open(struct mi_writer
*writer
);
633 * Machine interface for track/untrack a pid_target
635 * writer An instance of a machine interface writer.
637 * Returns zero if the element's value could be written.
638 * Negative values indicate an error.
640 int mi_lttng_pid_target(struct mi_writer
*writer
, pid_t pid
, int is_open
);
643 * Machine interface for struct lttng_calibrate.
645 * writer An instance of a machine interface writer.
647 * calibrate A lttng_calibrate instance.
649 * Returns zero if the element's value could be written.
650 * Negative values indicate an error.
652 int mi_lttng_calibrate(struct mi_writer
*writer
,
653 struct lttng_calibrate
*calibrate
);
656 * Machine interface of a context.
658 * writer An instance of a machine interface writer
660 * context An instance of a lttng_event_context
662 * is_open Define if we close the context element
663 * This should be used carefully and the client
664 * need to close the context element.
665 * Returns zero if the element's value could be written.
666 * Negative values indicate an error.
668 int mi_lttng_context(struct mi_writer
*writer
,
669 struct lttng_event_context
*context
, int is_open
);
672 * Machine interface of a perf_counter_context.
674 * writer An instance of a machine interface writer
676 * contest An instance of a lttng_event_perf_counter_ctx
678 * Returns zero if the element's value could be written.
679 * Negative values indicate an error.
681 int mi_lttng_perf_counter_context(struct mi_writer
*writer
,
682 struct lttng_event_perf_counter_ctx
*perf_context
);
685 * Machine interface of the snapshot list_output.
686 * It specifies the session for which we are listing snapshots,
687 * and it opens a snapshots element to list a sequence
690 * writer An instance of a machine interface writer.
692 * session_name: Snapshot output for session "session_name".
694 * Note: The client has to close the session and the snapshots elements after
695 * having listed every lttng_snapshot_output.
697 * Returns zero if the element's value could be written.
698 * Negative values indicate an error.
700 int mi_lttng_snapshot_output_session_name(struct mi_writer
*writer
,
701 const char *session_name
);
704 * Machine interface of the snapshot output.
705 * The machine interface serializes the following attributes:
706 * - id: ID of the snapshot output.
707 * - name: Name of the output.
708 * - data_url : Destination of the output.
709 * - ctrl_url: Destination of the output.
710 * - max_size: total size of all stream combined.
712 * writer An instance of a machine interface writer.
714 * output: A list of snapshot_output.
716 * Returns zero if the element's value could be written.
717 * Negative values indicate an error.
719 int mi_lttng_snapshot_list_output(struct mi_writer
*writer
,
720 struct lttng_snapshot_output
*output
);
723 * Machine interface of the output of the command snapshot del output
724 * when deleting a snapshot either by id or by name.
725 * If the snapshot was found and successfully deleted using its id,
726 * it return the id of the snapshot and the current session name on which it
729 * Otherwise, it do the same process with the name of the snapshot, if the
730 * snapshot output id is undefined.
732 * writer An instance of a machine interface writer.
734 * id: ID of the snapshot output.
736 * name: Name of the snapshot.
738 * current_session_name: Session to which the snapshot belongs.
740 * Returns zero if the element's value could be written.
741 * Negative values indicate an error.
743 int mi_lttng_snapshot_del_output(struct mi_writer
*writer
, int id
,
744 const char *name
, const char *current_session_name
);
747 * Machine interface of the output of the command snapshot add output
748 * when adding a snapshot from a user URL.
750 * If the snapshot was successfully added, the machine interface lists
752 * - id: ID of the newly add snapshot output.
753 * - current_session_name: Name of the session to which the output was added.
754 * - ctrl_url: Destination of the output.
755 * - max_size: total size of all stream combined.
757 * writer An instance of a machine interface writer.
759 * current_session_name: Session to which the snapshot belongs.
763 * output: iterator over a lttng_snapshot_output_list which contain
764 * the snapshot output informations.
766 * Returns zero if the element's value could be written.
767 * Negative values indicate an error.
769 int mi_lttng_snapshot_add_output(struct mi_writer
*writer
,
770 const char *current_session_name
, const char *n_ptr
,
771 struct lttng_snapshot_output
*output
);
774 * Machine interface of the output of the command snapshot
775 * record from a URL (if given).
777 * If the snapshot is successfully recorded from a url, the machine interface
778 * output the following information:
779 * - url: Destination of the output stored in the snapshot.
781 * Otherwise, the machine interface output the data and ctrl url received
782 * from the command-line.
784 * writer An instance of a machine interface writer.
786 * current_session_name: Snapshot record for session "current_session_name".
788 * ctrl_url, data_url: Destination of the output receive from the command-line.
790 * Returns zero if the element's value could be written.
791 * Negative values indicate an error.
793 int mi_lttng_snapshot_record(struct mi_writer
*writer
,
794 const char *current_session_name
, const char *url
,
795 const char *cmdline_ctrl_url
, const char *cmdline_data_url
);
797 #endif /* _MI_LTTNG_H */