Commit | Line | Data |
---|---|---|
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 | |
24 | #include <errno.h> | |
25 | #include <grp.h> | |
26 | #include <stdio.h> | |
27 | #include <stdlib.h> | |
28 | #include <string.h> | |
29 | #include <unistd.h> | |
30 | ||
5b97ec60 | 31 | #include <lttng/lttng.h> |
fac6795d | 32 | |
773168b7 | 33 | #include <lttng/lttng-sessiond-comm.h> |
fac6795d | 34 | #include "lttngerr.h" |
f3ed775e | 35 | #include "lttng-share.h" |
fac6795d DG |
36 | |
37 | /* Socket to session daemon for communication */ | |
38 | static int sessiond_socket; | |
39 | static char sessiond_sock_path[PATH_MAX]; | |
40 | ||
41 | /* Communication structure to ltt-sessiond */ | |
fac6795d | 42 | static struct lttcomm_session_msg lsm; |
5461b305 | 43 | static struct lttcomm_lttng_msg llm; |
fac6795d | 44 | |
fac6795d DG |
45 | /* Variables */ |
46 | static char *tracing_group; | |
47 | static int connected; | |
48 | ||
99497cd0 MD |
49 | /* |
50 | * Copy string from src to dst and enforce null terminated byte. | |
51 | */ | |
52 | static void copy_string(char *dst, const char *src, size_t len) | |
53 | { | |
54 | if (src && dst) { | |
55 | strncpy(dst, src, len); | |
56 | /* Enforce the NULL terminated byte */ | |
57 | dst[len - 1] = '\0'; | |
58 | } | |
59 | } | |
60 | ||
fac6795d | 61 | /* |
ca95a216 | 62 | * send_data_sessiond |
fac6795d | 63 | * |
e065084a | 64 | * Send lttcomm_session_msg to the session daemon. |
fac6795d DG |
65 | * |
66 | * On success, return 0 | |
67 | * On error, return error code | |
68 | */ | |
ca95a216 | 69 | static int send_data_sessiond(void) |
fac6795d DG |
70 | { |
71 | int ret; | |
72 | ||
73 | if (!connected) { | |
e065084a DG |
74 | ret = -ENOTCONN; |
75 | goto end; | |
fac6795d DG |
76 | } |
77 | ||
78 | ret = lttcomm_send_unix_sock(sessiond_socket, &lsm, sizeof(lsm)); | |
e065084a DG |
79 | |
80 | end: | |
81 | return ret; | |
82 | } | |
83 | ||
84 | /* | |
ca95a216 | 85 | * recv_data_sessiond |
e065084a DG |
86 | * |
87 | * Receive data from the sessiond socket. | |
88 | * | |
89 | * On success, return 0 | |
90 | * On error, return recv() error code | |
91 | */ | |
ca95a216 | 92 | static int recv_data_sessiond(void *buf, size_t len) |
e065084a DG |
93 | { |
94 | int ret; | |
95 | ||
96 | if (!connected) { | |
97 | ret = -ENOTCONN; | |
98 | goto end; | |
fac6795d DG |
99 | } |
100 | ||
ca95a216 | 101 | ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len); |
fac6795d | 102 | |
e065084a | 103 | end: |
fac6795d DG |
104 | return ret; |
105 | } | |
106 | ||
107 | /* | |
947308c4 | 108 | * Check if the specified group name exist. |
65beb5ff DG |
109 | * |
110 | * If yes return 0, else return -1. | |
947308c4 DG |
111 | */ |
112 | static int check_tracing_group(const char *grp_name) | |
113 | { | |
114 | struct group *grp_tracing; /* no free(). See getgrnam(3) */ | |
115 | gid_t *grp_list; | |
116 | int grp_list_size, grp_id, i; | |
117 | int ret = -1; | |
118 | ||
119 | /* Get GID of group 'tracing' */ | |
120 | grp_tracing = getgrnam(grp_name); | |
121 | if (grp_tracing == NULL) { | |
122 | /* NULL means not found also. getgrnam(3) */ | |
123 | if (errno != 0) { | |
124 | perror("getgrnam"); | |
125 | } | |
126 | goto end; | |
127 | } | |
128 | ||
129 | /* Get number of supplementary group IDs */ | |
130 | grp_list_size = getgroups(0, NULL); | |
131 | if (grp_list_size < 0) { | |
132 | perror("getgroups"); | |
133 | goto end; | |
134 | } | |
135 | ||
136 | /* Alloc group list of the right size */ | |
137 | grp_list = malloc(grp_list_size * sizeof(gid_t)); | |
138 | grp_id = getgroups(grp_list_size, grp_list); | |
139 | if (grp_id < -1) { | |
140 | perror("getgroups"); | |
141 | goto free_list; | |
142 | } | |
143 | ||
144 | for (i = 0; i < grp_list_size; i++) { | |
145 | if (grp_list[i] == grp_tracing->gr_gid) { | |
146 | ret = 0; | |
147 | break; | |
148 | } | |
149 | } | |
150 | ||
151 | free_list: | |
152 | free(grp_list); | |
153 | ||
154 | end: | |
155 | return ret; | |
156 | } | |
157 | ||
158 | /* | |
65beb5ff DG |
159 | * Set sessiond socket path by putting it in the global sessiond_sock_path |
160 | * variable. | |
947308c4 DG |
161 | */ |
162 | static int set_session_daemon_path(void) | |
163 | { | |
164 | int ret; | |
165 | ||
166 | /* Are we in the tracing group ? */ | |
167 | ret = check_tracing_group(tracing_group); | |
168 | if (ret < 0 && getuid() != 0) { | |
99497cd0 MD |
169 | if (snprintf(sessiond_sock_path, PATH_MAX, |
170 | DEFAULT_HOME_CLIENT_UNIX_SOCK, | |
171 | getenv("HOME")) < 0) { | |
947308c4 DG |
172 | return -ENOMEM; |
173 | } | |
174 | } else { | |
99497cd0 MD |
175 | copy_string(sessiond_sock_path, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, |
176 | PATH_MAX); | |
947308c4 DG |
177 | } |
178 | ||
179 | return 0; | |
180 | } | |
181 | ||
65beb5ff DG |
182 | /* |
183 | * Connect to the LTTng session daemon. | |
184 | * | |
185 | * On success, return 0. On error, return -1. | |
186 | */ | |
187 | static int connect_sessiond(void) | |
188 | { | |
189 | int ret; | |
190 | ||
191 | ret = set_session_daemon_path(); | |
192 | if (ret < 0) { | |
193 | return ret; | |
194 | } | |
195 | ||
196 | /* Connect to the sesssion daemon */ | |
197 | ret = lttcomm_connect_unix_sock(sessiond_sock_path); | |
198 | if (ret < 0) { | |
199 | return ret; | |
200 | } | |
201 | ||
202 | sessiond_socket = ret; | |
203 | connected = 1; | |
204 | ||
205 | return 0; | |
206 | } | |
207 | ||
208 | /* | |
209 | * Clean disconnect the session daemon. | |
210 | */ | |
211 | static int disconnect_sessiond(void) | |
212 | { | |
213 | int ret = 0; | |
214 | ||
215 | if (connected) { | |
216 | ret = lttcomm_close_unix_sock(sessiond_socket); | |
217 | sessiond_socket = 0; | |
218 | connected = 0; | |
219 | } | |
220 | ||
221 | return ret; | |
222 | } | |
223 | ||
35a6fdb7 DG |
224 | /* |
225 | * Reset the session message structure. | |
226 | */ | |
227 | static void reset_session_msg(void) | |
228 | { | |
229 | memset(&lsm, 0, sizeof(struct lttcomm_session_msg)); | |
230 | } | |
231 | ||
65beb5ff DG |
232 | /* |
233 | * ask_sessiond | |
234 | * | |
235 | * Ask the session daemon a specific command and put the data into buf. | |
236 | * | |
237 | * Return size of data (only payload, not header). | |
238 | */ | |
239 | static int ask_sessiond(enum lttcomm_sessiond_command lct, void **buf) | |
240 | { | |
241 | int ret; | |
242 | size_t size; | |
243 | void *data = NULL; | |
244 | ||
245 | ret = connect_sessiond(); | |
246 | if (ret < 0) { | |
247 | goto end; | |
248 | } | |
249 | ||
250 | lsm.cmd_type = lct; | |
251 | ||
252 | /* Send command to session daemon */ | |
253 | ret = send_data_sessiond(); | |
254 | if (ret < 0) { | |
255 | goto end; | |
256 | } | |
257 | ||
258 | /* Get header from data transmission */ | |
259 | ret = recv_data_sessiond(&llm, sizeof(llm)); | |
260 | if (ret < 0) { | |
261 | goto end; | |
262 | } | |
263 | ||
264 | /* Check error code if OK */ | |
265 | if (llm.ret_code != LTTCOMM_OK) { | |
266 | ret = -llm.ret_code; | |
267 | goto end; | |
268 | } | |
269 | ||
270 | size = llm.data_size; | |
271 | if (size == 0) { | |
7d29a247 | 272 | ret = 0; |
65beb5ff DG |
273 | goto end; |
274 | } | |
275 | ||
276 | data = (void*) malloc(size); | |
277 | ||
278 | /* Get payload data */ | |
279 | ret = recv_data_sessiond(data, size); | |
280 | if (ret < 0) { | |
281 | free(data); | |
282 | goto end; | |
283 | } | |
284 | ||
285 | *buf = data; | |
286 | ret = size; | |
287 | ||
288 | end: | |
289 | disconnect_sessiond(); | |
35a6fdb7 | 290 | reset_session_msg(); |
65beb5ff DG |
291 | return ret; |
292 | } | |
293 | ||
9f19cc17 | 294 | /* |
eb354453 DG |
295 | * Copy domain to lttcomm_session_msg domain. If unknown domain, default domain |
296 | * will be the kernel. | |
9f19cc17 | 297 | */ |
eb354453 | 298 | static void copy_lttng_domain(struct lttng_domain *dom) |
9f19cc17 | 299 | { |
eb354453 DG |
300 | if (dom) { |
301 | switch (dom->type) { | |
302 | case LTTNG_DOMAIN_KERNEL: | |
303 | case LTTNG_DOMAIN_UST: | |
304 | case LTTNG_DOMAIN_UST_EXEC_NAME: | |
305 | case LTTNG_DOMAIN_UST_PID: | |
306 | case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN: | |
307 | memcpy(&lsm.domain, dom, sizeof(struct lttng_domain)); | |
308 | break; | |
309 | default: | |
310 | lsm.domain.type = LTTNG_DOMAIN_KERNEL; | |
311 | break; | |
312 | } | |
313 | } | |
314 | } | |
315 | ||
1df4dedd | 316 | /* |
f3ed775e | 317 | * Start tracing for all trace of the session. |
1df4dedd | 318 | */ |
38057ed1 | 319 | int lttng_start_tracing(const char *session_name) |
f3ed775e | 320 | { |
42abccdb | 321 | copy_string(lsm.session.name, session_name, NAME_MAX); |
f3ed775e DG |
322 | return ask_sessiond(LTTNG_START_TRACE, NULL); |
323 | } | |
1df4dedd DG |
324 | |
325 | /* | |
f3ed775e DG |
326 | * Stop tracing for all trace of the session. |
327 | */ | |
38057ed1 | 328 | int lttng_stop_tracing(const char *session_name) |
f3ed775e | 329 | { |
42abccdb | 330 | copy_string(lsm.session.name, session_name, NAME_MAX); |
f3ed775e DG |
331 | return ask_sessiond(LTTNG_STOP_TRACE, NULL); |
332 | } | |
333 | ||
334 | /* | |
7d29a247 | 335 | * lttng_add_context |
1df4dedd | 336 | */ |
7d29a247 | 337 | int lttng_add_context(struct lttng_domain *domain, |
38057ed1 DG |
338 | struct lttng_event_context *ctx, const char *event_name, |
339 | const char *channel_name) | |
d65106b1 | 340 | { |
eb354453 DG |
341 | copy_string(lsm.u.context.channel_name, channel_name, NAME_MAX); |
342 | copy_string(lsm.u.context.event_name, event_name, NAME_MAX); | |
b579acd9 | 343 | copy_lttng_domain(domain); |
d65106b1 | 344 | |
eb354453 DG |
345 | if (ctx) { |
346 | memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context)); | |
d65106b1 DG |
347 | } |
348 | ||
b579acd9 | 349 | return ask_sessiond(LTTNG_ADD_CONTEXT, NULL); |
d65106b1 DG |
350 | } |
351 | ||
f3ed775e | 352 | /* |
7d29a247 | 353 | * lttng_enable_event |
f3ed775e | 354 | */ |
7d29a247 | 355 | int lttng_enable_event(struct lttng_domain *domain, |
38057ed1 | 356 | struct lttng_event *ev, const char *channel_name) |
1df4dedd | 357 | { |
0d0c377a | 358 | int ret; |
33a2b854 | 359 | |
94cf3c47 | 360 | if (channel_name == NULL) { |
eb354453 | 361 | copy_string(lsm.u.enable.channel_name, DEFAULT_CHANNEL_NAME, NAME_MAX); |
33a2b854 | 362 | } else { |
eb354453 DG |
363 | copy_string(lsm.u.enable.channel_name, channel_name, NAME_MAX); |
364 | } | |
365 | ||
0d0c377a DG |
366 | copy_lttng_domain(domain); |
367 | ||
368 | if (ev == NULL) { | |
369 | ret = ask_sessiond(LTTNG_ENABLE_ALL_EVENT, NULL); | |
370 | } else { | |
371 | memcpy(&lsm.u.enable.event, ev, sizeof(struct lttng_event)); | |
372 | ret = ask_sessiond(LTTNG_ENABLE_EVENT, NULL); | |
f3ed775e DG |
373 | } |
374 | ||
33a2b854 | 375 | return ret; |
1df4dedd DG |
376 | } |
377 | ||
378 | /* | |
f5177a38 | 379 | * Disable event of a channel and domain. |
1df4dedd | 380 | */ |
38057ed1 DG |
381 | int lttng_disable_event(struct lttng_domain *domain, const char *name, |
382 | const char *channel_name) | |
1df4dedd | 383 | { |
eb354453 | 384 | int ret = -1; |
1df4dedd | 385 | |
94cf3c47 | 386 | if (channel_name == NULL) { |
eb354453 | 387 | copy_string(lsm.u.disable.channel_name, DEFAULT_CHANNEL_NAME, NAME_MAX); |
f3ed775e | 388 | } else { |
eb354453 DG |
389 | copy_string(lsm.u.disable.channel_name, channel_name, NAME_MAX); |
390 | } | |
391 | ||
f5177a38 DG |
392 | copy_lttng_domain(domain); |
393 | ||
394 | if (name == NULL) { | |
395 | ret = ask_sessiond(LTTNG_DISABLE_ALL_EVENT, NULL); | |
396 | } else { | |
397 | copy_string(lsm.u.disable.name, name, NAME_MAX); | |
398 | ret = ask_sessiond(LTTNG_DISABLE_EVENT, NULL); | |
f3ed775e DG |
399 | } |
400 | ||
f3ed775e | 401 | return ret; |
1df4dedd DG |
402 | } |
403 | ||
404 | /* | |
0d0c377a | 405 | * Enable channel per domain |
a5c5a2bd | 406 | */ |
38057ed1 DG |
407 | int lttng_enable_channel(struct lttng_domain *domain, |
408 | struct lttng_channel *chan) | |
a5c5a2bd | 409 | { |
eb354453 DG |
410 | if (chan) { |
411 | memcpy(&lsm.u.channel.chan, chan, sizeof(struct lttng_channel)); | |
412 | } | |
7d29a247 | 413 | |
0d0c377a | 414 | copy_lttng_domain(domain); |
7d29a247 | 415 | |
0d0c377a | 416 | return ask_sessiond(LTTNG_ENABLE_CHANNEL, NULL); |
8c0faa1d | 417 | } |
1df4dedd | 418 | |
2ef84c95 | 419 | /* |
0b97ec54 | 420 | * All tracing will be stopped for registered events of the channel. |
2ef84c95 | 421 | */ |
38057ed1 | 422 | int lttng_disable_channel(struct lttng_domain *domain, const char *name) |
2ef84c95 | 423 | { |
eb354453 | 424 | copy_string(lsm.u.disable.channel_name, name, NAME_MAX); |
0b97ec54 | 425 | copy_lttng_domain(domain); |
1df4dedd | 426 | |
0b97ec54 | 427 | return ask_sessiond(LTTNG_DISABLE_CHANNEL, NULL); |
ca95a216 DG |
428 | } |
429 | ||
fac6795d | 430 | /* |
2a71efd5 | 431 | * List all available tracepoints of domain. |
fac6795d | 432 | * |
2a71efd5 | 433 | * Return the size (bytes) of the list and set the events array. |
7d29a247 | 434 | * On error, return negative value. |
fac6795d | 435 | */ |
2a71efd5 DG |
436 | int lttng_list_tracepoints(struct lttng_domain *domain, |
437 | struct lttng_event **events) | |
fac6795d | 438 | { |
052da939 | 439 | int ret; |
fac6795d | 440 | |
eb354453 | 441 | copy_lttng_domain(domain); |
2a71efd5 | 442 | |
052da939 DG |
443 | ret = ask_sessiond(LTTNG_LIST_TRACEPOINTS, (void **) events); |
444 | if (ret < 0) { | |
445 | return ret; | |
eb354453 | 446 | } |
fac6795d | 447 | |
9f19cc17 | 448 | return ret / sizeof(struct lttng_event); |
fac6795d DG |
449 | } |
450 | ||
1657e9bb | 451 | /* |
7d29a247 | 452 | * Return a human readable string of code |
1657e9bb | 453 | */ |
7d29a247 | 454 | const char *lttng_get_readable_code(int code) |
1657e9bb | 455 | { |
7d29a247 DG |
456 | if (code > -LTTCOMM_OK) { |
457 | return "Ended with errors"; | |
1657e9bb DG |
458 | } |
459 | ||
7d29a247 | 460 | return lttcomm_get_readable_code(code); |
1657e9bb DG |
461 | } |
462 | ||
aaf97519 | 463 | /* |
894be886 | 464 | * Create a brand new session using name. |
aaf97519 | 465 | */ |
38057ed1 | 466 | int lttng_create_session(const char *name, const char *path) |
aaf97519 | 467 | { |
42abccdb DG |
468 | copy_string(lsm.session.name, name, NAME_MAX); |
469 | copy_string(lsm.session.path, path, PATH_MAX); | |
947308c4 | 470 | return ask_sessiond(LTTNG_CREATE_SESSION, NULL); |
8028d920 DG |
471 | } |
472 | ||
473 | /* | |
8028d920 DG |
474 | * Destroy session using name. |
475 | */ | |
38057ed1 | 476 | int lttng_destroy_session(const char *name) |
8028d920 | 477 | { |
42abccdb | 478 | copy_string(lsm.session.name, name, NAME_MAX); |
947308c4 | 479 | return ask_sessiond(LTTNG_DESTROY_SESSION, NULL); |
aaf97519 DG |
480 | } |
481 | ||
57167058 | 482 | /* |
57167058 DG |
483 | * Ask the session daemon for all available sessions. |
484 | * | |
ca95a216 DG |
485 | * Return number of session. |
486 | * On error, return negative value. | |
57167058 | 487 | */ |
ca95a216 | 488 | int lttng_list_sessions(struct lttng_session **sessions) |
57167058 | 489 | { |
ca95a216 | 490 | int ret; |
57167058 | 491 | |
ca95a216 | 492 | ret = ask_sessiond(LTTNG_LIST_SESSIONS, (void**) sessions); |
57167058 | 493 | if (ret < 0) { |
ca95a216 | 494 | return ret; |
57167058 DG |
495 | } |
496 | ||
ca95a216 | 497 | return ret / sizeof(struct lttng_session); |
57167058 DG |
498 | } |
499 | ||
9f19cc17 DG |
500 | /* |
501 | * List domain of a session. | |
502 | */ | |
503 | int lttng_list_domains(const char *session_name, struct lttng_domain **domains) | |
504 | { | |
505 | int ret; | |
506 | ||
42abccdb | 507 | copy_string(lsm.session.name, session_name, NAME_MAX); |
9f19cc17 DG |
508 | ret = ask_sessiond(LTTNG_LIST_DOMAINS, (void**) domains); |
509 | if (ret < 0) { | |
510 | return ret; | |
511 | } | |
512 | ||
513 | return ret / sizeof(struct lttng_domain); | |
514 | } | |
515 | ||
516 | /* | |
517 | * List channels of a session | |
518 | */ | |
519 | int lttng_list_channels(struct lttng_domain *domain, | |
520 | const char *session_name, struct lttng_channel **channels) | |
521 | { | |
522 | int ret; | |
523 | ||
42abccdb | 524 | copy_string(lsm.session.name, session_name, NAME_MAX); |
eb354453 | 525 | copy_lttng_domain(domain); |
9f19cc17 DG |
526 | |
527 | ret = ask_sessiond(LTTNG_LIST_CHANNELS, (void**) channels); | |
528 | if (ret < 0) { | |
529 | return ret; | |
530 | } | |
531 | ||
532 | return ret / sizeof(struct lttng_channel); | |
533 | } | |
534 | ||
535 | /* | |
536 | * List events of a session channel. | |
537 | */ | |
538 | int lttng_list_events(struct lttng_domain *domain, | |
539 | const char *session_name, const char *channel_name, | |
540 | struct lttng_event **events) | |
541 | { | |
542 | int ret; | |
543 | ||
42abccdb | 544 | copy_string(lsm.session.name, session_name, NAME_MAX); |
eb354453 DG |
545 | copy_string(lsm.u.list.channel_name, channel_name, NAME_MAX); |
546 | copy_lttng_domain(domain); | |
9f19cc17 DG |
547 | |
548 | ret = ask_sessiond(LTTNG_LIST_EVENTS, (void**) events); | |
549 | if (ret < 0) { | |
550 | return ret; | |
551 | } | |
552 | ||
553 | return ret / sizeof(struct lttng_event); | |
554 | } | |
555 | ||
7d29a247 DG |
556 | /* |
557 | * Set session name for the current lsm. | |
558 | */ | |
38057ed1 | 559 | void lttng_set_session_name(const char *name) |
e8be5f4f | 560 | { |
42abccdb | 561 | copy_string(lsm.session.name, name, NAME_MAX); |
e8be5f4f DG |
562 | } |
563 | ||
fac6795d DG |
564 | /* |
565 | * lttng_set_tracing_group | |
566 | * | |
567 | * Set tracing group variable with name. This function | |
568 | * allocate memory pointed by tracing_group. | |
569 | */ | |
570 | int lttng_set_tracing_group(const char *name) | |
571 | { | |
572 | if (asprintf(&tracing_group, "%s", name) < 0) { | |
573 | return -ENOMEM; | |
574 | } | |
575 | ||
576 | return 0; | |
577 | } | |
578 | ||
d0254c7c MD |
579 | /* |
580 | * lttng_calibrate | |
581 | */ | |
582 | int lttng_calibrate(struct lttng_domain *domain, | |
583 | struct lttng_calibrate *calibrate) | |
584 | { | |
585 | int ret; | |
586 | ||
587 | copy_lttng_domain(domain); | |
588 | ||
589 | memcpy(&lsm.u.calibrate, calibrate, sizeof(struct lttng_calibrate)); | |
590 | ret = ask_sessiond(LTTNG_CALIBRATE, NULL); | |
591 | ||
592 | return ret; | |
593 | } | |
594 | ||
fac6795d DG |
595 | /* |
596 | * lttng_check_session_daemon | |
597 | * | |
947308c4 DG |
598 | * Yes, return 1 |
599 | * No, return 0 | |
600 | * Error, return negative value | |
fac6795d | 601 | */ |
947308c4 | 602 | int lttng_session_daemon_alive(void) |
fac6795d DG |
603 | { |
604 | int ret; | |
605 | ||
606 | ret = set_session_daemon_path(); | |
607 | if (ret < 0) { | |
947308c4 | 608 | /* Error */ |
fac6795d DG |
609 | return ret; |
610 | } | |
611 | ||
7d8234d9 | 612 | /* If socket exist, we check if the daemon listens to connect. */ |
fac6795d DG |
613 | ret = access(sessiond_sock_path, F_OK); |
614 | if (ret < 0) { | |
947308c4 DG |
615 | /* Not alive */ |
616 | return 0; | |
fac6795d DG |
617 | } |
618 | ||
7d8234d9 MD |
619 | ret = lttcomm_connect_unix_sock(sessiond_sock_path); |
620 | if (ret < 0) { | |
621 | /* Not alive */ | |
622 | return 0; | |
623 | } | |
624 | ret = lttcomm_close_unix_sock(ret); | |
625 | if (ret < 0) | |
626 | perror("lttcomm_close_unix_sock"); | |
627 | ||
947308c4 DG |
628 | /* Is alive */ |
629 | return 1; | |
fac6795d DG |
630 | } |
631 | ||
632 | /* | |
633 | * lib constructor | |
634 | */ | |
635 | static void __attribute__((constructor)) init() | |
636 | { | |
637 | /* Set default session group */ | |
64a23ac4 | 638 | lttng_set_tracing_group(LTTNG_DEFAULT_TRACING_GROUP); |
fac6795d | 639 | } |