Commit | Line | Data |
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826d496d MD |
1 | /* |
2 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> | |
fac6795d DG |
3 | * |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation; either version 2 | |
7 | * of the License, or (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
fac6795d DG |
17 | */ |
18 | ||
19 | #define _GNU_SOURCE | |
20 | #include <errno.h> | |
21 | #include <grp.h> | |
22 | #include <stdio.h> | |
23 | #include <stdlib.h> | |
24 | #include <string.h> | |
25 | #include <unistd.h> | |
26 | ||
5b97ec60 | 27 | #include <lttng/lttng.h> |
fac6795d DG |
28 | |
29 | #include "liblttsessiondcomm.h" | |
30 | #include "lttngerr.h" | |
f3ed775e | 31 | #include "lttng-share.h" |
fac6795d DG |
32 | |
33 | /* Socket to session daemon for communication */ | |
34 | static int sessiond_socket; | |
35 | static char sessiond_sock_path[PATH_MAX]; | |
36 | ||
37 | /* Communication structure to ltt-sessiond */ | |
fac6795d | 38 | static struct lttcomm_session_msg lsm; |
5461b305 | 39 | static struct lttcomm_lttng_msg llm; |
fac6795d | 40 | |
fac6795d DG |
41 | /* Variables */ |
42 | static char *tracing_group; | |
43 | static int connected; | |
44 | ||
45 | /* | |
ca95a216 | 46 | * send_data_sessiond |
fac6795d | 47 | * |
e065084a | 48 | * Send lttcomm_session_msg to the session daemon. |
fac6795d DG |
49 | * |
50 | * On success, return 0 | |
51 | * On error, return error code | |
52 | */ | |
ca95a216 | 53 | static int send_data_sessiond(void) |
fac6795d DG |
54 | { |
55 | int ret; | |
56 | ||
57 | if (!connected) { | |
e065084a DG |
58 | ret = -ENOTCONN; |
59 | goto end; | |
fac6795d DG |
60 | } |
61 | ||
62 | ret = lttcomm_send_unix_sock(sessiond_socket, &lsm, sizeof(lsm)); | |
e065084a DG |
63 | |
64 | end: | |
65 | return ret; | |
66 | } | |
67 | ||
68 | /* | |
ca95a216 | 69 | * recv_data_sessiond |
e065084a DG |
70 | * |
71 | * Receive data from the sessiond socket. | |
72 | * | |
73 | * On success, return 0 | |
74 | * On error, return recv() error code | |
75 | */ | |
ca95a216 | 76 | static int recv_data_sessiond(void *buf, size_t len) |
e065084a DG |
77 | { |
78 | int ret; | |
79 | ||
80 | if (!connected) { | |
81 | ret = -ENOTCONN; | |
82 | goto end; | |
fac6795d DG |
83 | } |
84 | ||
ca95a216 | 85 | ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len); |
fac6795d | 86 | |
e065084a | 87 | end: |
fac6795d DG |
88 | return ret; |
89 | } | |
90 | ||
91 | /* | |
ca95a216 | 92 | * ask_sessiond |
fac6795d | 93 | * |
947308c4 | 94 | * Ask the session daemon a specific command and put the data into buf. |
ca95a216 DG |
95 | * |
96 | * Return size of data (only payload, not header). | |
fac6795d | 97 | */ |
6abb15de | 98 | static int ask_sessiond(enum lttcomm_sessiond_command lct, void **buf) |
fac6795d | 99 | { |
ca95a216 DG |
100 | int ret; |
101 | size_t size; | |
102 | void *data = NULL; | |
ca95a216 | 103 | |
7442b2ba DG |
104 | ret = lttng_connect_sessiond(); |
105 | if (ret < 0) { | |
106 | goto end; | |
107 | } | |
108 | ||
ca95a216 DG |
109 | lsm.cmd_type = lct; |
110 | ||
111 | /* Send command to session daemon */ | |
112 | ret = send_data_sessiond(); | |
113 | if (ret < 0) { | |
114 | goto end; | |
fac6795d DG |
115 | } |
116 | ||
ca95a216 | 117 | /* Get header from data transmission */ |
5461b305 | 118 | ret = recv_data_sessiond(&llm, sizeof(llm)); |
ca95a216 DG |
119 | if (ret < 0) { |
120 | goto end; | |
121 | } | |
fac6795d | 122 | |
ca95a216 | 123 | /* Check error code if OK */ |
5461b305 DG |
124 | if (llm.ret_code != LTTCOMM_OK) { |
125 | ret = -llm.ret_code; | |
ca95a216 DG |
126 | goto end; |
127 | } | |
fac6795d | 128 | |
f3ed775e | 129 | size = llm.data_size; |
ca95a216 DG |
130 | if (size == 0) { |
131 | goto end; | |
fac6795d DG |
132 | } |
133 | ||
ca95a216 DG |
134 | data = (void*) malloc(size); |
135 | ||
136 | /* Get payload data */ | |
137 | ret = recv_data_sessiond(data, size); | |
fac6795d | 138 | if (ret < 0) { |
947308c4 | 139 | free(data); |
fac6795d DG |
140 | goto end; |
141 | } | |
142 | ||
ca95a216 DG |
143 | *buf = data; |
144 | ret = size; | |
fac6795d DG |
145 | |
146 | end: | |
7442b2ba | 147 | lttng_disconnect_sessiond(); |
fac6795d DG |
148 | return ret; |
149 | } | |
150 | ||
947308c4 DG |
151 | /* |
152 | * check_tracing_group | |
153 | * | |
154 | * Check if the specified group name exist. | |
155 | * If yes, 0, else -1 | |
156 | */ | |
157 | static int check_tracing_group(const char *grp_name) | |
158 | { | |
159 | struct group *grp_tracing; /* no free(). See getgrnam(3) */ | |
160 | gid_t *grp_list; | |
161 | int grp_list_size, grp_id, i; | |
162 | int ret = -1; | |
163 | ||
164 | /* Get GID of group 'tracing' */ | |
165 | grp_tracing = getgrnam(grp_name); | |
166 | if (grp_tracing == NULL) { | |
167 | /* NULL means not found also. getgrnam(3) */ | |
168 | if (errno != 0) { | |
169 | perror("getgrnam"); | |
170 | } | |
171 | goto end; | |
172 | } | |
173 | ||
174 | /* Get number of supplementary group IDs */ | |
175 | grp_list_size = getgroups(0, NULL); | |
176 | if (grp_list_size < 0) { | |
177 | perror("getgroups"); | |
178 | goto end; | |
179 | } | |
180 | ||
181 | /* Alloc group list of the right size */ | |
182 | grp_list = malloc(grp_list_size * sizeof(gid_t)); | |
183 | grp_id = getgroups(grp_list_size, grp_list); | |
184 | if (grp_id < -1) { | |
185 | perror("getgroups"); | |
186 | goto free_list; | |
187 | } | |
188 | ||
189 | for (i = 0; i < grp_list_size; i++) { | |
190 | if (grp_list[i] == grp_tracing->gr_gid) { | |
191 | ret = 0; | |
192 | break; | |
193 | } | |
194 | } | |
195 | ||
196 | free_list: | |
197 | free(grp_list); | |
198 | ||
199 | end: | |
200 | return ret; | |
201 | } | |
202 | ||
203 | /* | |
204 | * set_session_daemon_path | |
205 | * | |
206 | * Set sessiond socket path by putting it in | |
207 | * the global sessiond_sock_path variable. | |
208 | */ | |
209 | static int set_session_daemon_path(void) | |
210 | { | |
211 | int ret; | |
212 | ||
213 | /* Are we in the tracing group ? */ | |
214 | ret = check_tracing_group(tracing_group); | |
215 | if (ret < 0 && getuid() != 0) { | |
216 | if (sprintf(sessiond_sock_path, DEFAULT_HOME_CLIENT_UNIX_SOCK, | |
217 | getenv("HOME")) < 0) { | |
218 | return -ENOMEM; | |
219 | } | |
220 | } else { | |
221 | strncpy(sessiond_sock_path, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, | |
222 | sizeof(DEFAULT_GLOBAL_CLIENT_UNIX_SOCK)); | |
223 | } | |
224 | ||
225 | return 0; | |
226 | } | |
227 | ||
1df4dedd | 228 | /* |
f3ed775e DG |
229 | * lttng_start_tracing |
230 | * | |
231 | * Start tracing for all trace of the session. | |
1df4dedd | 232 | */ |
f3ed775e DG |
233 | int lttng_start_tracing(char *session_name) |
234 | { | |
235 | strncpy(lsm.session_name, session_name, NAME_MAX); | |
236 | return ask_sessiond(LTTNG_START_TRACE, NULL); | |
237 | } | |
1df4dedd DG |
238 | |
239 | /* | |
f3ed775e | 240 | * lttng_stop_tracing |
1df4dedd | 241 | * |
f3ed775e DG |
242 | * Stop tracing for all trace of the session. |
243 | */ | |
244 | int lttng_stop_tracing(char *session_name) | |
245 | { | |
246 | strncpy(lsm.session_name, session_name, NAME_MAX); | |
247 | return ask_sessiond(LTTNG_STOP_TRACE, NULL); | |
248 | } | |
249 | ||
250 | /* | |
251 | * BEGIN Kernel control API | |
1df4dedd | 252 | */ |
f3ed775e DG |
253 | |
254 | /* | |
255 | * lttng_kernel_enable_event | |
256 | */ | |
257 | int lttng_kernel_enable_event(struct lttng_event *ev, char *channel_name) | |
1df4dedd | 258 | { |
33a2b854 DG |
259 | int ret; |
260 | ||
f3ed775e DG |
261 | if (strlen(channel_name) == 0) { |
262 | strncpy(lsm.u.enable.channel_name, DEFAULT_CHANNEL_NAME, NAME_MAX); | |
33a2b854 | 263 | } else { |
f3ed775e DG |
264 | strncpy(lsm.u.enable.channel_name, channel_name, NAME_MAX); |
265 | } | |
266 | ||
267 | if (ev == NULL) { | |
268 | ret = ask_sessiond(LTTNG_KERNEL_ENABLE_ALL_EVENT, NULL); | |
269 | } else { | |
270 | memcpy(&lsm.u.enable.event, ev, sizeof(struct lttng_event)); | |
271 | ret = ask_sessiond(LTTNG_KERNEL_ENABLE_EVENT, NULL); | |
33a2b854 DG |
272 | } |
273 | ||
274 | return ret; | |
1df4dedd DG |
275 | } |
276 | ||
277 | /* | |
278 | * lttng_kernel_disable_event | |
279 | * | |
280 | * Disable an event in the kernel tracer. | |
281 | */ | |
f3ed775e | 282 | int lttng_kernel_disable_event(char *name, char *channel_name) |
1df4dedd | 283 | { |
f3ed775e | 284 | int ret; |
1df4dedd | 285 | |
f3ed775e DG |
286 | if (strlen(channel_name) == 0) { |
287 | strncpy(lsm.u.disable.channel_name, DEFAULT_CHANNEL_NAME, NAME_MAX); | |
288 | } else { | |
289 | strncpy(lsm.u.disable.channel_name, channel_name, NAME_MAX); | |
290 | } | |
291 | ||
292 | if (name == NULL) { | |
293 | ret = ask_sessiond(LTTNG_KERNEL_DISABLE_ALL_EVENT, NULL); | |
294 | } else { | |
295 | strncpy(lsm.u.disable.name, name, NAME_MAX); | |
296 | ret = ask_sessiond(LTTNG_KERNEL_DISABLE_EVENT, NULL); | |
297 | } | |
298 | ||
299 | return ret; | |
1df4dedd DG |
300 | } |
301 | ||
302 | /* | |
f3ed775e | 303 | * lttng_kernel_enable_channel |
1df4dedd | 304 | * |
f3ed775e | 305 | * Enable recording for a channel for the kernel tracer. |
1df4dedd | 306 | */ |
f3ed775e | 307 | int lttng_kernel_enable_channel(char *name) |
1df4dedd | 308 | { |
d36b8583 | 309 | strncpy(lsm.u.enable.channel_name, name, NAME_MAX); |
f3ed775e | 310 | return ask_sessiond(LTTNG_KERNEL_ENABLE_CHANNEL, NULL); |
1df4dedd | 311 | } |
a5c5a2bd DG |
312 | |
313 | /* | |
f3ed775e | 314 | * lttng_kernel_disable_channel |
a5c5a2bd | 315 | * |
f3ed775e | 316 | * Disable recording for the channel for the kernel tracer. |
a5c5a2bd | 317 | */ |
f3ed775e | 318 | int lttng_kernel_disable_channel(char *name) |
a5c5a2bd | 319 | { |
f3ed775e | 320 | return ask_sessiond(LTTNG_KERNEL_DISABLE_CHANNEL, NULL); |
a5c5a2bd | 321 | } |
8c0faa1d DG |
322 | |
323 | /* | |
f3ed775e | 324 | * lttng_kernel_create_channel |
8c0faa1d | 325 | * |
f3ed775e | 326 | * Create a channel in the kernel tracer. |
8c0faa1d | 327 | */ |
f3ed775e | 328 | int lttng_kernel_create_channel(struct lttng_channel *chan) |
8c0faa1d | 329 | { |
f3ed775e DG |
330 | memcpy(&lsm.u.channel.chan, chan, sizeof(struct lttng_channel)); |
331 | return ask_sessiond(LTTNG_KERNEL_CREATE_CHANNEL, NULL); | |
8c0faa1d | 332 | } |
1df4dedd | 333 | |
2ef84c95 | 334 | /* |
f3ed775e | 335 | * lttng_list_events |
2ef84c95 DG |
336 | * |
337 | * List all available events in the kernel. | |
338 | * | |
339 | * Return the size (bytes) of the list and set the event_list array. | |
340 | * On error, return negative value. | |
341 | */ | |
342 | int lttng_kernel_list_events(char **event_list) | |
343 | { | |
f3ed775e | 344 | return ask_sessiond(LTTNG_KERNEL_LIST_EVENTS, (void **) event_list); |
2ef84c95 DG |
345 | } |
346 | ||
1df4dedd | 347 | /* |
f3ed775e | 348 | * END Kernel control API |
1df4dedd DG |
349 | */ |
350 | ||
ca95a216 DG |
351 | /* |
352 | * lttng_get_readable_code | |
353 | * | |
354 | * Return a human readable string of code | |
355 | */ | |
356 | const char *lttng_get_readable_code(int code) | |
357 | { | |
358 | if (code > -LTTCOMM_OK) { | |
359 | return "Ended with errors"; | |
360 | } | |
361 | ||
362 | return lttcomm_get_readable_code(code); | |
363 | } | |
364 | ||
fac6795d DG |
365 | /* |
366 | * lttng_ust_list_apps | |
367 | * | |
947308c4 | 368 | * Ask the session daemon for all UST traceable applications. |
fac6795d | 369 | * |
ca95a216 DG |
370 | * Return the number of pids. |
371 | * On error, return negative value. | |
fac6795d | 372 | */ |
f3ed775e | 373 | int lttng_ust_list_traceable_apps(pid_t **pids) |
fac6795d | 374 | { |
ca95a216 | 375 | int ret; |
fac6795d | 376 | |
f3ed775e | 377 | ret = ask_sessiond(LTTNG_LIST_TRACEABLE_APPS, (void**) pids); |
fac6795d | 378 | if (ret < 0) { |
ca95a216 | 379 | return ret; |
fac6795d DG |
380 | } |
381 | ||
ca95a216 | 382 | return ret / sizeof(pid_t); |
fac6795d DG |
383 | } |
384 | ||
1657e9bb DG |
385 | /* |
386 | * lttng_list_traces | |
387 | * | |
947308c4 | 388 | * Ask the session daemon for all traces (kernel and ust) for the session |
f3ed775e | 389 | * identified by name. |
1657e9bb DG |
390 | * |
391 | * Return the number of traces. | |
947308c4 | 392 | * On error, return negative value. |
1657e9bb | 393 | */ |
f3ed775e DG |
394 | /* |
395 | int lttng_list_traces(char *session_name, struct lttng_trace **traces) | |
1657e9bb DG |
396 | { |
397 | int ret; | |
398 | ||
f3ed775e | 399 | strncpy(lsm.session_name, session_name, NAME_MAX); |
1657e9bb DG |
400 | |
401 | ret = ask_sessiond(LTTNG_LIST_TRACES, (void **) traces); | |
402 | if (ret < 0) { | |
403 | return ret; | |
404 | } | |
405 | ||
406 | return ret / sizeof(struct lttng_trace); | |
407 | } | |
f3ed775e | 408 | */ |
1657e9bb | 409 | |
aaf97519 DG |
410 | /* |
411 | * lttng_create_session | |
412 | * | |
894be886 | 413 | * Create a brand new session using name. |
aaf97519 | 414 | */ |
f3ed775e | 415 | int lttng_create_session(char *name, char *path) |
aaf97519 | 416 | { |
947308c4 | 417 | strncpy(lsm.session_name, name, NAME_MAX); |
f3ed775e | 418 | strncpy(lsm.path, path, PATH_MAX); |
947308c4 | 419 | return ask_sessiond(LTTNG_CREATE_SESSION, NULL); |
8028d920 DG |
420 | } |
421 | ||
422 | /* | |
423 | * lttng_destroy_session | |
424 | * | |
425 | * Destroy session using name. | |
426 | */ | |
f3ed775e | 427 | int lttng_destroy_session(char *name) |
8028d920 | 428 | { |
f3ed775e | 429 | strncpy(lsm.session_name, name, NAME_MAX); |
947308c4 | 430 | return ask_sessiond(LTTNG_DESTROY_SESSION, NULL); |
aaf97519 DG |
431 | } |
432 | ||
57167058 DG |
433 | /* |
434 | * lttng_list_sessions | |
435 | * | |
436 | * Ask the session daemon for all available sessions. | |
437 | * | |
ca95a216 DG |
438 | * Return number of session. |
439 | * On error, return negative value. | |
57167058 | 440 | */ |
ca95a216 | 441 | int lttng_list_sessions(struct lttng_session **sessions) |
57167058 | 442 | { |
ca95a216 | 443 | int ret; |
57167058 | 444 | |
ca95a216 | 445 | ret = ask_sessiond(LTTNG_LIST_SESSIONS, (void**) sessions); |
57167058 | 446 | if (ret < 0) { |
ca95a216 | 447 | return ret; |
57167058 DG |
448 | } |
449 | ||
ca95a216 | 450 | return ret / sizeof(struct lttng_session); |
57167058 DG |
451 | } |
452 | ||
fac6795d DG |
453 | /* |
454 | * lttng_connect_sessiond | |
455 | * | |
456 | * Connect to the LTTng session daemon. | |
457 | * On success, return 0 | |
458 | * On error, return a negative value | |
459 | */ | |
460 | int lttng_connect_sessiond(void) | |
461 | { | |
462 | int ret; | |
463 | ||
464 | ret = set_session_daemon_path(); | |
465 | if (ret < 0) { | |
466 | return ret; | |
467 | } | |
468 | ||
469 | /* Connect to the sesssion daemon */ | |
470 | ret = lttcomm_connect_unix_sock(sessiond_sock_path); | |
471 | if (ret < 0) { | |
472 | return ret; | |
473 | } | |
474 | ||
475 | sessiond_socket = ret; | |
476 | connected = 1; | |
477 | ||
478 | return 0; | |
479 | } | |
480 | ||
87378cf5 DG |
481 | /* |
482 | * lttng_disconnect_sessiond | |
483 | * | |
484 | * Clean disconnect the session daemon. | |
485 | */ | |
486 | int lttng_disconnect_sessiond(void) | |
487 | { | |
488 | int ret = 0; | |
489 | ||
490 | if (connected) { | |
491 | ret = lttcomm_close_unix_sock(sessiond_socket); | |
492 | sessiond_socket = 0; | |
493 | connected = 0; | |
494 | } | |
495 | ||
496 | return ret; | |
497 | } | |
498 | ||
f3ed775e | 499 | void lttng_set_session_name(char *name) |
e8be5f4f | 500 | { |
f3ed775e | 501 | strncpy(lsm.session_name, name, NAME_MAX); |
e8be5f4f DG |
502 | } |
503 | ||
fac6795d DG |
504 | /* |
505 | * lttng_set_tracing_group | |
506 | * | |
507 | * Set tracing group variable with name. This function | |
508 | * allocate memory pointed by tracing_group. | |
509 | */ | |
510 | int lttng_set_tracing_group(const char *name) | |
511 | { | |
512 | if (asprintf(&tracing_group, "%s", name) < 0) { | |
513 | return -ENOMEM; | |
514 | } | |
515 | ||
516 | return 0; | |
517 | } | |
518 | ||
519 | /* | |
520 | * lttng_check_session_daemon | |
521 | * | |
947308c4 DG |
522 | * Yes, return 1 |
523 | * No, return 0 | |
524 | * Error, return negative value | |
fac6795d | 525 | */ |
947308c4 | 526 | int lttng_session_daemon_alive(void) |
fac6795d DG |
527 | { |
528 | int ret; | |
529 | ||
530 | ret = set_session_daemon_path(); | |
531 | if (ret < 0) { | |
947308c4 | 532 | /* Error */ |
fac6795d DG |
533 | return ret; |
534 | } | |
535 | ||
536 | /* If socket exist, we consider the daemon started */ | |
537 | ret = access(sessiond_sock_path, F_OK); | |
538 | if (ret < 0) { | |
947308c4 DG |
539 | /* Not alive */ |
540 | return 0; | |
fac6795d DG |
541 | } |
542 | ||
947308c4 DG |
543 | /* Is alive */ |
544 | return 1; | |
fac6795d DG |
545 | } |
546 | ||
547 | /* | |
548 | * lib constructor | |
549 | */ | |
550 | static void __attribute__((constructor)) init() | |
551 | { | |
552 | /* Set default session group */ | |
64a23ac4 | 553 | lttng_set_tracing_group(LTTNG_DEFAULT_TRACING_GROUP); |
fac6795d | 554 | } |