Update loglevel ABI
[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.c
CommitLineData
826d496d 1/*
82a3637f
DG
2 * liblttngctl.c
3 *
4 * Linux Trace Toolkit Control Library
5 *
826d496d 6 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
fac6795d 7 *
82a3637f
DG
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; only
11 * version 2.1 of the License.
12 *
13 * This library is distributed in the hope that it will be useful,
fac6795d 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
82a3637f
DG
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
fac6795d
DG
21 */
22
23#define _GNU_SOURCE
fac6795d 24#include <grp.h>
1e307fab 25#include <errno.h>
fac6795d
DG
26#include <stdio.h>
27#include <stdlib.h>
28#include <string.h>
29#include <unistd.h>
30
990570ed
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31#include <common/common.h>
32#include <common/defaults.h>
db758600 33#include <common/sessiond-comm/sessiond-comm.h>
1e307fab 34#include <lttng/lttng.h>
fac6795d
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35
36/* Socket to session daemon for communication */
37static int sessiond_socket;
38static char sessiond_sock_path[PATH_MAX];
39
fac6795d
DG
40/* Variables */
41static char *tracing_group;
42static int connected;
43
99497cd0
MD
44/*
45 * Copy string from src to dst and enforce null terminated byte.
46 */
47static void copy_string(char *dst, const char *src, size_t len)
48{
e7d6716d 49 if (src && dst) {
99497cd0
MD
50 strncpy(dst, src, len);
51 /* Enforce the NULL terminated byte */
52 dst[len - 1] = '\0';
cd80958d
DG
53 } else if (dst) {
54 dst[0] = '\0';
99497cd0
MD
55 }
56}
57
fac6795d 58/*
cd80958d 59 * Copy domain to lttcomm_session_msg domain.
fac6795d 60 *
cd80958d
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61 * If domain is unknown, default domain will be the kernel.
62 */
63static void copy_lttng_domain(struct lttng_domain *dst, struct lttng_domain *src)
64{
65 if (src && dst) {
66 switch (src->type) {
67 case LTTNG_DOMAIN_KERNEL:
68 case LTTNG_DOMAIN_UST:
d78d6610 69 /*
cd80958d
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70 case LTTNG_DOMAIN_UST_EXEC_NAME:
71 case LTTNG_DOMAIN_UST_PID:
72 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
d78d6610 73 */
cd80958d
DG
74 memcpy(dst, src, sizeof(struct lttng_domain));
75 break;
76 default:
77 dst->type = LTTNG_DOMAIN_KERNEL;
78 break;
79 }
80 }
81}
82
83/*
84 * Send lttcomm_session_msg to the session daemon.
fac6795d 85 *
1c8d13c8
TD
86 * On success, returns the number of bytes sent (>=0)
87 * On error, returns -1
fac6795d 88 */
cd80958d 89static int send_session_msg(struct lttcomm_session_msg *lsm)
fac6795d
DG
90{
91 int ret;
92
93 if (!connected) {
e065084a
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94 ret = -ENOTCONN;
95 goto end;
fac6795d
DG
96 }
97
be040666 98 ret = lttcomm_send_creds_unix_sock(sessiond_socket, lsm,
cd80958d 99 sizeof(struct lttcomm_session_msg));
e065084a
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100
101end:
102 return ret;
103}
104
105/*
cd80958d 106 * Receive data from the sessiond socket.
e065084a 107 *
1c8d13c8
TD
108 * On success, returns the number of bytes received (>=0)
109 * On error, returns -1 (recvmsg() error) or -ENOTCONN
e065084a 110 */
ca95a216 111static int recv_data_sessiond(void *buf, size_t len)
e065084a
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112{
113 int ret;
114
115 if (!connected) {
116 ret = -ENOTCONN;
117 goto end;
fac6795d
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118 }
119
ca95a216 120 ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len);
fac6795d 121
e065084a 122end:
fac6795d
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123 return ret;
124}
125
126/*
1c8d13c8 127 * Check if we are in the specified group.
65beb5ff 128 *
2269e89e 129 * If yes return 1, else return -1.
947308c4
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130 */
131static int check_tracing_group(const char *grp_name)
132{
133 struct group *grp_tracing; /* no free(). See getgrnam(3) */
134 gid_t *grp_list;
135 int grp_list_size, grp_id, i;
136 int ret = -1;
137
138 /* Get GID of group 'tracing' */
139 grp_tracing = getgrnam(grp_name);
140 if (grp_tracing == NULL) {
141 /* NULL means not found also. getgrnam(3) */
142 if (errno != 0) {
143 perror("getgrnam");
144 }
145 goto end;
146 }
147
148 /* Get number of supplementary group IDs */
149 grp_list_size = getgroups(0, NULL);
150 if (grp_list_size < 0) {
151 perror("getgroups");
152 goto end;
153 }
154
155 /* Alloc group list of the right size */
156 grp_list = malloc(grp_list_size * sizeof(gid_t));
00795392 157 if (!grp_list) {
1c8d13c8 158 perror("malloc");
00795392
MD
159 goto end;
160 }
947308c4 161 grp_id = getgroups(grp_list_size, grp_list);
1c8d13c8 162 if (grp_id < 0) {
947308c4
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163 perror("getgroups");
164 goto free_list;
165 }
166
167 for (i = 0; i < grp_list_size; i++) {
168 if (grp_list[i] == grp_tracing->gr_gid) {
2269e89e 169 ret = 1;
947308c4
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170 break;
171 }
172 }
173
174free_list:
175 free(grp_list);
176
177end:
178 return ret;
179}
180
181/*
2269e89e
DG
182 * Try connect to session daemon with sock_path.
183 *
184 * Return 0 on success, else -1
185 */
186static int try_connect_sessiond(const char *sock_path)
187{
188 int ret;
189
190 /* If socket exist, we check if the daemon listens for connect. */
191 ret = access(sock_path, F_OK);
192 if (ret < 0) {
193 /* Not alive */
194 return -1;
195 }
196
197 ret = lttcomm_connect_unix_sock(sock_path);
198 if (ret < 0) {
199 /* Not alive */
200 return -1;
201 }
202
203 ret = lttcomm_close_unix_sock(ret);
204 if (ret < 0) {
205 perror("lttcomm_close_unix_sock");
206 }
207
208 return 0;
209}
210
211/*
1c8d13c8
TD
212 * Set sessiond socket path by putting it in the global
213 * sessiond_sock_path variable.
214 * Returns 0 on success,
215 * -ENOMEM on failure (the sessiond socket path is somehow too long)
947308c4
DG
216 */
217static int set_session_daemon_path(void)
218{
219 int ret;
2269e89e
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220 int in_tgroup = 0; /* In tracing group */
221 uid_t uid;
222
223 uid = getuid();
947308c4 224
2269e89e
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225 if (uid != 0) {
226 /* Are we in the tracing group ? */
227 in_tgroup = check_tracing_group(tracing_group);
228 }
229
08a9c49f
TD
230 if ((uid == 0) || in_tgroup) {
231 copy_string(sessiond_sock_path, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK,
2269e89e 232 sizeof(sessiond_sock_path));
08a9c49f 233 }
2269e89e 234
08a9c49f
TD
235 if (uid != 0) {
236 if (in_tgroup) {
237 /* Tracing group */
238 ret = try_connect_sessiond(sessiond_sock_path);
239 if (ret >= 0) {
240 goto end;
2269e89e 241 }
08a9c49f 242 /* Global session daemon not available... */
2269e89e 243 }
08a9c49f
TD
244 /* ...or not in tracing group (and not root), default */
245
246 /*
247 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
248 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
249 */
250 ret = snprintf(sessiond_sock_path, sizeof(sessiond_sock_path),
251 DEFAULT_HOME_CLIENT_UNIX_SOCK, getenv("HOME"));
252 if ((ret < 0) || (ret >= sizeof(sessiond_sock_path))) {
947308c4
DG
253 return -ENOMEM;
254 }
947308c4 255 }
08a9c49f 256end:
947308c4
DG
257 return 0;
258}
259
65beb5ff
DG
260/*
261 * Connect to the LTTng session daemon.
262 *
263 * On success, return 0. On error, return -1.
264 */
265static int connect_sessiond(void)
266{
267 int ret;
268
269 ret = set_session_daemon_path();
270 if (ret < 0) {
1c8d13c8 271 return -1; /* set_session_daemon_path() returns -ENOMEM */
65beb5ff
DG
272 }
273
274 /* Connect to the sesssion daemon */
275 ret = lttcomm_connect_unix_sock(sessiond_sock_path);
276 if (ret < 0) {
277 return ret;
278 }
279
280 sessiond_socket = ret;
281 connected = 1;
282
283 return 0;
284}
285
286/*
1c8d13c8
TD
287 * Clean disconnect from the session daemon.
288 * On success, return 0. On error, return -1.
65beb5ff
DG
289 */
290static int disconnect_sessiond(void)
291{
292 int ret = 0;
293
294 if (connected) {
295 ret = lttcomm_close_unix_sock(sessiond_socket);
296 sessiond_socket = 0;
297 connected = 0;
298 }
299
300 return ret;
301}
302
35a6fdb7 303/*
cd80958d 304 * Ask the session daemon a specific command and put the data into buf.
65beb5ff 305 *
af87c45a 306 * Return size of data (only payload, not header) or a negative error code.
65beb5ff 307 */
cd80958d 308static int ask_sessiond(struct lttcomm_session_msg *lsm, void **buf)
65beb5ff
DG
309{
310 int ret;
311 size_t size;
312 void *data = NULL;
cd80958d 313 struct lttcomm_lttng_msg llm;
65beb5ff
DG
314
315 ret = connect_sessiond();
316 if (ret < 0) {
317 goto end;
318 }
319
65beb5ff 320 /* Send command to session daemon */
cd80958d 321 ret = send_session_msg(lsm);
65beb5ff
DG
322 if (ret < 0) {
323 goto end;
324 }
325
326 /* Get header from data transmission */
327 ret = recv_data_sessiond(&llm, sizeof(llm));
328 if (ret < 0) {
329 goto end;
330 }
331
332 /* Check error code if OK */
333 if (llm.ret_code != LTTCOMM_OK) {
334 ret = -llm.ret_code;
335 goto end;
336 }
337
338 size = llm.data_size;
339 if (size == 0) {
874d3f84 340 /* If client free with size 0 */
a45d5536
DG
341 if (buf != NULL) {
342 *buf = NULL;
343 }
7d29a247 344 ret = 0;
65beb5ff
DG
345 goto end;
346 }
347
348 data = (void*) malloc(size);
349
350 /* Get payload data */
351 ret = recv_data_sessiond(data, size);
352 if (ret < 0) {
353 free(data);
354 goto end;
355 }
356
83009e5e
DG
357 /*
358 * Extra protection not to dereference a NULL pointer. If buf is NULL at
359 * this point, an error is returned and data is freed.
360 */
361 if (buf == NULL) {
362 ret = -1;
363 free(data);
364 goto end;
365 }
366
65beb5ff
DG
367 *buf = data;
368 ret = size;
369
370end:
371 disconnect_sessiond();
372 return ret;
373}
374
9f19cc17 375/*
cd80958d 376 * Create lttng handle and return pointer.
1c8d13c8 377 * The returned pointer will be NULL in case of malloc() error.
9f19cc17 378 */
cd80958d
DG
379struct lttng_handle *lttng_create_handle(const char *session_name,
380 struct lttng_domain *domain)
9f19cc17 381{
cd80958d
DG
382 struct lttng_handle *handle;
383
384 handle = malloc(sizeof(struct lttng_handle));
385 if (handle == NULL) {
386 perror("malloc handle");
387 goto end;
388 }
389
390 /* Copy session name */
391 copy_string(handle->session_name, session_name,
392 sizeof(handle->session_name));
393
394 /* Copy lttng domain */
395 copy_lttng_domain(&handle->domain, domain);
396
397end:
398 return handle;
399}
400
401/*
402 * Destroy handle by free(3) the pointer.
403 */
404void lttng_destroy_handle(struct lttng_handle *handle)
405{
406 if (handle) {
407 free(handle);
eb354453
DG
408 }
409}
410
d9800920
DG
411/*
412 * Register an outside consumer.
1c8d13c8 413 * Returns size of returned session payload data or a negative error code.
d9800920
DG
414 */
415int lttng_register_consumer(struct lttng_handle *handle,
416 const char *socket_path)
417{
418 struct lttcomm_session_msg lsm;
419
420 lsm.cmd_type = LTTNG_REGISTER_CONSUMER;
421 copy_string(lsm.session.name, handle->session_name,
422 sizeof(lsm.session.name));
423 copy_lttng_domain(&lsm.domain, &handle->domain);
424
425 copy_string(lsm.u.reg.path, socket_path, sizeof(lsm.u.reg.path));
426
427 return ask_sessiond(&lsm, NULL);
428}
429
1df4dedd 430/*
1c8d13c8
TD
431 * Start tracing for all traces of the session.
432 * Returns size of returned session payload data or a negative error code.
1df4dedd 433 */
6a4f824d 434int lttng_start_tracing(const char *session_name)
f3ed775e 435{
cd80958d
DG
436 struct lttcomm_session_msg lsm;
437
6a4f824d 438 if (session_name == NULL) {
cd80958d
DG
439 return -1;
440 }
441
442 lsm.cmd_type = LTTNG_START_TRACE;
6a4f824d
DG
443
444 copy_string(lsm.session.name, session_name, sizeof(lsm.session.name));
cd80958d
DG
445
446 return ask_sessiond(&lsm, NULL);
f3ed775e 447}
1df4dedd
DG
448
449/*
1c8d13c8
TD
450 * Stop tracing for all traces of the session.
451 * Returns size of returned session payload data or a negative error code.
f3ed775e 452 */
6a4f824d 453int lttng_stop_tracing(const char *session_name)
f3ed775e 454{
cd80958d
DG
455 struct lttcomm_session_msg lsm;
456
6a4f824d
DG
457 if (session_name == NULL) {
458 return -1;
459 }
460
cd80958d 461 lsm.cmd_type = LTTNG_STOP_TRACE;
6a4f824d
DG
462
463 copy_string(lsm.session.name, session_name, sizeof(lsm.session.name));
cd80958d
DG
464
465 return ask_sessiond(&lsm, NULL);
f3ed775e
DG
466}
467
468/*
cd80958d 469 * Add context to event or/and channel.
af87c45a
DG
470 *
471 * Returns the size of the returned payload data or a negative error code.
1df4dedd 472 */
cd80958d 473int lttng_add_context(struct lttng_handle *handle,
38057ed1
DG
474 struct lttng_event_context *ctx, const char *event_name,
475 const char *channel_name)
d65106b1 476{
cd80958d
DG
477 struct lttcomm_session_msg lsm;
478
9d697d3d
DG
479 /* Safety check. Both are mandatory */
480 if (handle == NULL || ctx == NULL) {
cd80958d
DG
481 return -1;
482 }
483
484 lsm.cmd_type = LTTNG_ADD_CONTEXT;
485
486 /* Copy channel name */
487 copy_string(lsm.u.context.channel_name, channel_name,
488 sizeof(lsm.u.context.channel_name));
489 /* Copy event name */
490 copy_string(lsm.u.context.event_name, event_name,
491 sizeof(lsm.u.context.event_name));
492
493 copy_lttng_domain(&lsm.domain, &handle->domain);
d65106b1 494
9d697d3d 495 memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context));
d65106b1 496
cd80958d
DG
497 copy_string(lsm.session.name, handle->session_name,
498 sizeof(lsm.session.name));
499
500 return ask_sessiond(&lsm, NULL);
d65106b1
DG
501}
502
f3ed775e 503/*
1c8d13c8
TD
504 * Enable event(s) for a channel.
505 * If no event name is specified, all events are enabled.
506 * If no channel name is specified, the default 'channel0' is used.
507 * Returns size of returned session payload data or a negative error code.
f3ed775e 508 */
cd80958d 509int lttng_enable_event(struct lttng_handle *handle,
38057ed1 510 struct lttng_event *ev, const char *channel_name)
1df4dedd 511{
cd80958d
DG
512 struct lttcomm_session_msg lsm;
513
5117eeec 514 if (handle == NULL || ev == NULL) {
cd80958d
DG
515 return -1;
516 }
33a2b854 517
5117eeec 518 /* If no channel name, we put the default name */
94cf3c47 519 if (channel_name == NULL) {
cd80958d
DG
520 copy_string(lsm.u.enable.channel_name, DEFAULT_CHANNEL_NAME,
521 sizeof(lsm.u.enable.channel_name));
33a2b854 522 } else {
cd80958d
DG
523 copy_string(lsm.u.enable.channel_name, channel_name,
524 sizeof(lsm.u.enable.channel_name));
eb354453
DG
525 }
526
cd80958d 527 copy_lttng_domain(&lsm.domain, &handle->domain);
0d0c377a 528
8c9ae521 529 if (ev->name[0] != '\0') {
cd80958d 530 lsm.cmd_type = LTTNG_ENABLE_EVENT;
0d0c377a 531 } else {
cd80958d 532 lsm.cmd_type = LTTNG_ENABLE_ALL_EVENT;
f3ed775e 533 }
8c9ae521 534 memcpy(&lsm.u.enable.event, ev, sizeof(lsm.u.enable.event));
f3ed775e 535
cd80958d
DG
536 copy_string(lsm.session.name, handle->session_name,
537 sizeof(lsm.session.name));
538
539 return ask_sessiond(&lsm, NULL);
1df4dedd
DG
540}
541
542/*
1c8d13c8
TD
543 * Disable event(s) of a channel and domain.
544 * If no event name is specified, all events are disabled.
545 * If no channel name is specified, the default 'channel0' is used.
546 * Returns size of returned session payload data or a negative error code.
1df4dedd 547 */
cd80958d 548int lttng_disable_event(struct lttng_handle *handle, const char *name,
38057ed1 549 const char *channel_name)
1df4dedd 550{
cd80958d 551 struct lttcomm_session_msg lsm;
1df4dedd 552
9d697d3d 553 if (handle == NULL) {
cd80958d
DG
554 return -1;
555 }
556
557 if (channel_name) {
558 copy_string(lsm.u.disable.channel_name, channel_name,
559 sizeof(lsm.u.disable.channel_name));
f3ed775e 560 } else {
cd80958d
DG
561 copy_string(lsm.u.disable.channel_name, DEFAULT_CHANNEL_NAME,
562 sizeof(lsm.u.disable.channel_name));
eb354453
DG
563 }
564
cd80958d 565 copy_lttng_domain(&lsm.domain, &handle->domain);
f5177a38 566
f84efadf 567 if (name != NULL) {
cd80958d
DG
568 copy_string(lsm.u.disable.name, name, sizeof(lsm.u.disable.name));
569 lsm.cmd_type = LTTNG_DISABLE_EVENT;
f5177a38 570 } else {
cd80958d 571 lsm.cmd_type = LTTNG_DISABLE_ALL_EVENT;
f3ed775e
DG
572 }
573
cd80958d
DG
574 copy_string(lsm.session.name, handle->session_name,
575 sizeof(lsm.session.name));
576
577 return ask_sessiond(&lsm, NULL);
1df4dedd
DG
578}
579
580/*
1c8d13c8
TD
581 * Enable channel per domain
582 * Returns size of returned session payload data or a negative error code.
a5c5a2bd 583 */
cd80958d 584int lttng_enable_channel(struct lttng_handle *handle,
38057ed1 585 struct lttng_channel *chan)
a5c5a2bd 586{
cd80958d
DG
587 struct lttcomm_session_msg lsm;
588
5117eeec
DG
589 /*
590 * NULL arguments are forbidden. No default values.
591 */
592 if (handle == NULL || chan == NULL) {
cd80958d
DG
593 return -1;
594 }
595
5117eeec 596 memcpy(&lsm.u.channel.chan, chan, sizeof(lsm.u.channel.chan));
7d29a247 597
cd80958d
DG
598 lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
599
600 copy_lttng_domain(&lsm.domain, &handle->domain);
7d29a247 601
cd80958d
DG
602 copy_string(lsm.session.name, handle->session_name,
603 sizeof(lsm.session.name));
604
605 return ask_sessiond(&lsm, NULL);
8c0faa1d 606}
1df4dedd 607
2ef84c95 608/*
1c8d13c8
TD
609 * All tracing will be stopped for registered events of the channel.
610 * Returns size of returned session payload data or a negative error code.
2ef84c95 611 */
cd80958d 612int lttng_disable_channel(struct lttng_handle *handle, const char *name)
2ef84c95 613{
cd80958d
DG
614 struct lttcomm_session_msg lsm;
615
9d697d3d
DG
616 /* Safety check. Both are mandatory */
617 if (handle == NULL || name == NULL) {
cd80958d
DG
618 return -1;
619 }
620
cd80958d 621 lsm.cmd_type = LTTNG_DISABLE_CHANNEL;
1df4dedd 622
9d697d3d
DG
623 copy_string(lsm.u.disable.channel_name, name,
624 sizeof(lsm.u.disable.channel_name));
625
cd80958d
DG
626 copy_lttng_domain(&lsm.domain, &handle->domain);
627
628 copy_string(lsm.session.name, handle->session_name,
629 sizeof(lsm.session.name));
630
631 return ask_sessiond(&lsm, NULL);
ca95a216
DG
632}
633
fac6795d 634/*
1c8d13c8
TD
635 * Lists all available tracepoints of domain.
636 * Sets the contents of the events array.
637 * Returns the number of lttng_event entries in events;
638 * on error, returns a negative value.
fac6795d 639 */
cd80958d 640int lttng_list_tracepoints(struct lttng_handle *handle,
2a71efd5 641 struct lttng_event **events)
fac6795d 642{
052da939 643 int ret;
cd80958d
DG
644 struct lttcomm_session_msg lsm;
645
9d697d3d 646 if (handle == NULL) {
cd80958d
DG
647 return -1;
648 }
fac6795d 649
cd80958d
DG
650 lsm.cmd_type = LTTNG_LIST_TRACEPOINTS;
651 copy_lttng_domain(&lsm.domain, &handle->domain);
2a71efd5 652
cd80958d 653 ret = ask_sessiond(&lsm, (void **) events);
052da939
DG
654 if (ret < 0) {
655 return ret;
eb354453 656 }
fac6795d 657
9f19cc17 658 return ret / sizeof(struct lttng_event);
fac6795d
DG
659}
660
1657e9bb 661/*
1c8d13c8
TD
662 * Returns a human readable string describing
663 * the error code (a negative value).
1657e9bb 664 */
9a745bc7 665const char *lttng_strerror(int code)
1657e9bb 666{
1c8d13c8 667 /* lttcomm error codes range from -LTTCOMM_OK down to -LTTCOMM_NR */
7d29a247
DG
668 if (code > -LTTCOMM_OK) {
669 return "Ended with errors";
1657e9bb
DG
670 }
671
7d29a247 672 return lttcomm_get_readable_code(code);
1657e9bb
DG
673}
674
aaf97519 675/*
1c8d13c8
TD
676 * Create a brand new session using name and path.
677 * Returns size of returned session payload data or a negative error code.
aaf97519 678 */
38057ed1 679int lttng_create_session(const char *name, const char *path)
aaf97519 680{
cd80958d
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681 struct lttcomm_session_msg lsm;
682
683 lsm.cmd_type = LTTNG_CREATE_SESSION;
684 copy_string(lsm.session.name, name, sizeof(lsm.session.name));
685 copy_string(lsm.session.path, path, sizeof(lsm.session.path));
686
687 return ask_sessiond(&lsm, NULL);
8028d920
DG
688}
689
690/*
8028d920 691 * Destroy session using name.
1c8d13c8 692 * Returns size of returned session payload data or a negative error code.
8028d920 693 */
843f5df9 694int lttng_destroy_session(const char *session_name)
8028d920 695{
cd80958d
DG
696 struct lttcomm_session_msg lsm;
697
843f5df9 698 if (session_name == NULL) {
cd80958d
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699 return -1;
700 }
701
702 lsm.cmd_type = LTTNG_DESTROY_SESSION;
843f5df9
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703
704 copy_string(lsm.session.name, session_name, sizeof(lsm.session.name));
cd80958d
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705
706 return ask_sessiond(&lsm, NULL);
aaf97519
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707}
708
57167058 709/*
57167058 710 * Ask the session daemon for all available sessions.
1c8d13c8
TD
711 * Sets the contents of the sessions array.
712 * Returns the number of lttng_session entries in sessions;
713 * on error, returns a negative value.
57167058 714 */
ca95a216 715int lttng_list_sessions(struct lttng_session **sessions)
57167058 716{
ca95a216 717 int ret;
cd80958d 718 struct lttcomm_session_msg lsm;
57167058 719
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720 lsm.cmd_type = LTTNG_LIST_SESSIONS;
721 ret = ask_sessiond(&lsm, (void**) sessions);
57167058 722 if (ret < 0) {
ca95a216 723 return ret;
57167058
DG
724 }
725
ca95a216 726 return ret / sizeof(struct lttng_session);
57167058
DG
727}
728
9f19cc17 729/*
1c8d13c8
TD
730 * Ask the session daemon for all available domains of a session.
731 * Sets the contents of the domains array.
732 * Returns the number of lttng_domain entries in domains;
733 * on error, returns a negative value.
9f19cc17 734 */
330be774 735int lttng_list_domains(const char *session_name,
cd80958d 736 struct lttng_domain **domains)
9f19cc17
DG
737{
738 int ret;
cd80958d
DG
739 struct lttcomm_session_msg lsm;
740
330be774 741 if (session_name == NULL) {
cd80958d
DG
742 return -1;
743 }
9f19cc17 744
cd80958d
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745 lsm.cmd_type = LTTNG_LIST_DOMAINS;
746
330be774 747 copy_string(lsm.session.name, session_name, sizeof(lsm.session.name));
cd80958d
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748
749 ret = ask_sessiond(&lsm, (void**) domains);
9f19cc17
DG
750 if (ret < 0) {
751 return ret;
752 }
753
754 return ret / sizeof(struct lttng_domain);
755}
756
757/*
1c8d13c8
TD
758 * Ask the session daemon for all available channels of a session.
759 * Sets the contents of the channels array.
760 * Returns the number of lttng_channel entries in channels;
761 * on error, returns a negative value.
9f19cc17 762 */
cd80958d
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763int lttng_list_channels(struct lttng_handle *handle,
764 struct lttng_channel **channels)
9f19cc17
DG
765{
766 int ret;
cd80958d
DG
767 struct lttcomm_session_msg lsm;
768
9d697d3d 769 if (handle == NULL) {
cd80958d
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770 return -1;
771 }
772
773 lsm.cmd_type = LTTNG_LIST_CHANNELS;
774 copy_string(lsm.session.name, handle->session_name,
775 sizeof(lsm.session.name));
9f19cc17 776
cd80958d 777 copy_lttng_domain(&lsm.domain, &handle->domain);
9f19cc17 778
cd80958d 779 ret = ask_sessiond(&lsm, (void**) channels);
9f19cc17
DG
780 if (ret < 0) {
781 return ret;
782 }
783
784 return ret / sizeof(struct lttng_channel);
785}
786
787/*
1c8d13c8
TD
788 * Ask the session daemon for all available events of a session channel.
789 * Sets the contents of the events array.
790 * Returns the number of lttng_event entries in events;
791 * on error, returns a negative value.
9f19cc17 792 */
cd80958d
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793int lttng_list_events(struct lttng_handle *handle,
794 const char *channel_name, struct lttng_event **events)
9f19cc17
DG
795{
796 int ret;
cd80958d 797 struct lttcomm_session_msg lsm;
9f19cc17 798
9d697d3d
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799 /* Safety check. An handle and channel name are mandatory */
800 if (handle == NULL || channel_name == NULL) {
cd80958d
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801 return -1;
802 }
803
804 lsm.cmd_type = LTTNG_LIST_EVENTS;
805 copy_string(lsm.session.name, handle->session_name,
806 sizeof(lsm.session.name));
807 copy_string(lsm.u.list.channel_name, channel_name,
808 sizeof(lsm.u.list.channel_name));
809
810 copy_lttng_domain(&lsm.domain, &handle->domain);
9f19cc17 811
cd80958d 812 ret = ask_sessiond(&lsm, (void**) events);
9f19cc17
DG
813 if (ret < 0) {
814 return ret;
815 }
816
817 return ret / sizeof(struct lttng_event);
818}
819
fac6795d 820/*
1c8d13c8
TD
821 * Sets the tracing_group variable with name.
822 * This function allocates memory pointed to by tracing_group.
823 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
fac6795d
DG
824 */
825int lttng_set_tracing_group(const char *name)
826{
9d697d3d
DG
827 if (name == NULL) {
828 return -1;
829 }
830
fac6795d
DG
831 if (asprintf(&tracing_group, "%s", name) < 0) {
832 return -ENOMEM;
833 }
834
835 return 0;
836}
837
d0254c7c 838/*
af87c45a 839 * Returns size of returned session payload data or a negative error code.
d0254c7c 840 */
cd80958d 841int lttng_calibrate(struct lttng_handle *handle,
d0254c7c
MD
842 struct lttng_calibrate *calibrate)
843{
cd80958d 844 struct lttcomm_session_msg lsm;
d0254c7c 845
9d697d3d
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846 /* Safety check. NULL pointer are forbidden */
847 if (handle == NULL || calibrate == NULL) {
cd80958d
DG
848 return -1;
849 }
d0254c7c 850
cd80958d
DG
851 lsm.cmd_type = LTTNG_CALIBRATE;
852 copy_lttng_domain(&lsm.domain, &handle->domain);
d0254c7c 853
cd80958d
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854 memcpy(&lsm.u.calibrate, calibrate, sizeof(lsm.u.calibrate));
855
856 return ask_sessiond(&lsm, NULL);
d0254c7c
MD
857}
858
5edd7e09
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859/*
860 * Set default channel attributes.
1c8d13c8 861 * If either or both of the arguments are null, nothing happens.
5edd7e09
DG
862 */
863void lttng_channel_set_default_attr(struct lttng_domain *domain,
864 struct lttng_channel_attr *attr)
865{
866 /* Safety check */
867 if (attr == NULL || domain == NULL) {
868 return;
869 }
870
871 switch (domain->type) {
872 case LTTNG_DOMAIN_KERNEL:
873 attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
874 attr->switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
875 attr->read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
876
877 attr->subbuf_size = DEFAULT_KERNEL_CHANNEL_SUBBUF_SIZE;
878 attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
879 attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
880 break;
881 case LTTNG_DOMAIN_UST:
d78d6610 882#if 0
5edd7e09
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883 case LTTNG_DOMAIN_UST_EXEC_NAME:
884 case LTTNG_DOMAIN_UST_PID:
885 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
d78d6610 886#endif
5edd7e09
DG
887 attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
888 attr->switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
889 attr->read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
890
891 attr->subbuf_size = DEFAULT_UST_CHANNEL_SUBBUF_SIZE;
892 attr->num_subbuf = DEFAULT_UST_CHANNEL_SUBBUF_NUM;
893 attr->output = DEFAULT_UST_CHANNEL_OUTPUT;
894 break;
895 default:
896 /* Default behavior */
897 memset(attr, 0, sizeof(struct lttng_channel_attr));
898 break;
899 }
900}
901
fac6795d 902/*
2269e89e 903 * Check if session daemon is alive.
fac6795d 904 *
2269e89e 905 * Return 1 if alive or 0 if not.
1c8d13c8 906 * On error returns a negative value.
fac6795d 907 */
947308c4 908int lttng_session_daemon_alive(void)
fac6795d
DG
909{
910 int ret;
911
912 ret = set_session_daemon_path();
913 if (ret < 0) {
947308c4 914 /* Error */
fac6795d
DG
915 return ret;
916 }
917
2269e89e
DG
918 if (strlen(sessiond_sock_path) == 0) {
919 /* No socket path set. Weird error */
920 return -1;
fac6795d
DG
921 }
922
2269e89e 923 ret = try_connect_sessiond(sessiond_sock_path);
7d8234d9
MD
924 if (ret < 0) {
925 /* Not alive */
926 return 0;
927 }
7d8234d9 928
947308c4
DG
929 /* Is alive */
930 return 1;
fac6795d
DG
931}
932
933/*
934 * lib constructor
935 */
936static void __attribute__((constructor)) init()
937{
938 /* Set default session group */
bbccc3d2 939 lttng_set_tracing_group(DEFAULT_TRACING_GROUP);
fac6795d 940}
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