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 | /* | |
947308c4 | 92 | * Check if the specified group name exist. |
65beb5ff DG |
93 | * |
94 | * If yes return 0, else return -1. | |
947308c4 DG |
95 | */ |
96 | static int check_tracing_group(const char *grp_name) | |
97 | { | |
98 | struct group *grp_tracing; /* no free(). See getgrnam(3) */ | |
99 | gid_t *grp_list; | |
100 | int grp_list_size, grp_id, i; | |
101 | int ret = -1; | |
102 | ||
103 | /* Get GID of group 'tracing' */ | |
104 | grp_tracing = getgrnam(grp_name); | |
105 | if (grp_tracing == NULL) { | |
106 | /* NULL means not found also. getgrnam(3) */ | |
107 | if (errno != 0) { | |
108 | perror("getgrnam"); | |
109 | } | |
110 | goto end; | |
111 | } | |
112 | ||
113 | /* Get number of supplementary group IDs */ | |
114 | grp_list_size = getgroups(0, NULL); | |
115 | if (grp_list_size < 0) { | |
116 | perror("getgroups"); | |
117 | goto end; | |
118 | } | |
119 | ||
120 | /* Alloc group list of the right size */ | |
121 | grp_list = malloc(grp_list_size * sizeof(gid_t)); | |
122 | grp_id = getgroups(grp_list_size, grp_list); | |
123 | if (grp_id < -1) { | |
124 | perror("getgroups"); | |
125 | goto free_list; | |
126 | } | |
127 | ||
128 | for (i = 0; i < grp_list_size; i++) { | |
129 | if (grp_list[i] == grp_tracing->gr_gid) { | |
130 | ret = 0; | |
131 | break; | |
132 | } | |
133 | } | |
134 | ||
135 | free_list: | |
136 | free(grp_list); | |
137 | ||
138 | end: | |
139 | return ret; | |
140 | } | |
141 | ||
142 | /* | |
65beb5ff DG |
143 | * Set sessiond socket path by putting it in the global sessiond_sock_path |
144 | * variable. | |
947308c4 DG |
145 | */ |
146 | static int set_session_daemon_path(void) | |
147 | { | |
148 | int ret; | |
149 | ||
150 | /* Are we in the tracing group ? */ | |
151 | ret = check_tracing_group(tracing_group); | |
152 | if (ret < 0 && getuid() != 0) { | |
153 | if (sprintf(sessiond_sock_path, DEFAULT_HOME_CLIENT_UNIX_SOCK, | |
154 | getenv("HOME")) < 0) { | |
155 | return -ENOMEM; | |
156 | } | |
157 | } else { | |
158 | strncpy(sessiond_sock_path, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, | |
159 | sizeof(DEFAULT_GLOBAL_CLIENT_UNIX_SOCK)); | |
160 | } | |
161 | ||
162 | return 0; | |
163 | } | |
164 | ||
65beb5ff DG |
165 | /* |
166 | * Connect to the LTTng session daemon. | |
167 | * | |
168 | * On success, return 0. On error, return -1. | |
169 | */ | |
170 | static int connect_sessiond(void) | |
171 | { | |
172 | int ret; | |
173 | ||
174 | ret = set_session_daemon_path(); | |
175 | if (ret < 0) { | |
176 | return ret; | |
177 | } | |
178 | ||
179 | /* Connect to the sesssion daemon */ | |
180 | ret = lttcomm_connect_unix_sock(sessiond_sock_path); | |
181 | if (ret < 0) { | |
182 | return ret; | |
183 | } | |
184 | ||
185 | sessiond_socket = ret; | |
186 | connected = 1; | |
187 | ||
188 | return 0; | |
189 | } | |
190 | ||
191 | /* | |
192 | * Clean disconnect the session daemon. | |
193 | */ | |
194 | static int disconnect_sessiond(void) | |
195 | { | |
196 | int ret = 0; | |
197 | ||
198 | if (connected) { | |
199 | ret = lttcomm_close_unix_sock(sessiond_socket); | |
200 | sessiond_socket = 0; | |
201 | connected = 0; | |
202 | } | |
203 | ||
204 | return ret; | |
205 | } | |
206 | ||
207 | /* | |
208 | * ask_sessiond | |
209 | * | |
210 | * Ask the session daemon a specific command and put the data into buf. | |
211 | * | |
212 | * Return size of data (only payload, not header). | |
213 | */ | |
214 | static int ask_sessiond(enum lttcomm_sessiond_command lct, void **buf) | |
215 | { | |
216 | int ret; | |
217 | size_t size; | |
218 | void *data = NULL; | |
219 | ||
220 | ret = connect_sessiond(); | |
221 | if (ret < 0) { | |
222 | goto end; | |
223 | } | |
224 | ||
225 | lsm.cmd_type = lct; | |
226 | ||
227 | /* Send command to session daemon */ | |
228 | ret = send_data_sessiond(); | |
229 | if (ret < 0) { | |
230 | goto end; | |
231 | } | |
232 | ||
233 | /* Get header from data transmission */ | |
234 | ret = recv_data_sessiond(&llm, sizeof(llm)); | |
235 | if (ret < 0) { | |
236 | goto end; | |
237 | } | |
238 | ||
239 | /* Check error code if OK */ | |
240 | if (llm.ret_code != LTTCOMM_OK) { | |
241 | ret = -llm.ret_code; | |
242 | goto end; | |
243 | } | |
244 | ||
245 | size = llm.data_size; | |
246 | if (size == 0) { | |
247 | goto end; | |
248 | } | |
249 | ||
250 | data = (void*) malloc(size); | |
251 | ||
252 | /* Get payload data */ | |
253 | ret = recv_data_sessiond(data, size); | |
254 | if (ret < 0) { | |
255 | free(data); | |
256 | goto end; | |
257 | } | |
258 | ||
259 | *buf = data; | |
260 | ret = size; | |
261 | ||
262 | end: | |
263 | disconnect_sessiond(); | |
264 | return ret; | |
265 | } | |
266 | ||
1df4dedd | 267 | /* |
f3ed775e DG |
268 | * lttng_start_tracing |
269 | * | |
270 | * Start tracing for all trace of the session. | |
1df4dedd | 271 | */ |
f3ed775e DG |
272 | int lttng_start_tracing(char *session_name) |
273 | { | |
274 | strncpy(lsm.session_name, session_name, NAME_MAX); | |
275 | return ask_sessiond(LTTNG_START_TRACE, NULL); | |
276 | } | |
1df4dedd DG |
277 | |
278 | /* | |
f3ed775e | 279 | * lttng_stop_tracing |
1df4dedd | 280 | * |
f3ed775e DG |
281 | * Stop tracing for all trace of the session. |
282 | */ | |
283 | int lttng_stop_tracing(char *session_name) | |
284 | { | |
285 | strncpy(lsm.session_name, session_name, NAME_MAX); | |
286 | return ask_sessiond(LTTNG_STOP_TRACE, NULL); | |
287 | } | |
288 | ||
289 | /* | |
290 | * BEGIN Kernel control API | |
1df4dedd | 291 | */ |
f3ed775e | 292 | |
d65106b1 DG |
293 | /* |
294 | * lttng_kernel_add_context | |
295 | */ | |
296 | int lttng_kernel_add_context(struct lttng_kernel_context *ctx, | |
297 | char *event_name, char *channel_name) | |
298 | { | |
94cf3c47 | 299 | if (channel_name != NULL) { |
d65106b1 DG |
300 | strncpy(lsm.u.context.channel_name, channel_name, NAME_MAX); |
301 | } | |
302 | ||
94cf3c47 | 303 | if (event_name != NULL) { |
d65106b1 DG |
304 | strncpy(lsm.u.context.event_name, event_name, NAME_MAX); |
305 | } | |
306 | ||
307 | memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_kernel_context)); | |
308 | return ask_sessiond(LTTNG_KERNEL_ADD_CONTEXT, NULL); | |
309 | } | |
310 | ||
f3ed775e DG |
311 | /* |
312 | * lttng_kernel_enable_event | |
313 | */ | |
314 | int lttng_kernel_enable_event(struct lttng_event *ev, char *channel_name) | |
1df4dedd | 315 | { |
33a2b854 DG |
316 | int ret; |
317 | ||
94cf3c47 | 318 | if (channel_name == NULL) { |
f3ed775e | 319 | strncpy(lsm.u.enable.channel_name, DEFAULT_CHANNEL_NAME, NAME_MAX); |
33a2b854 | 320 | } else { |
f3ed775e DG |
321 | strncpy(lsm.u.enable.channel_name, channel_name, NAME_MAX); |
322 | } | |
323 | ||
324 | if (ev == NULL) { | |
325 | ret = ask_sessiond(LTTNG_KERNEL_ENABLE_ALL_EVENT, NULL); | |
326 | } else { | |
327 | memcpy(&lsm.u.enable.event, ev, sizeof(struct lttng_event)); | |
328 | ret = ask_sessiond(LTTNG_KERNEL_ENABLE_EVENT, NULL); | |
33a2b854 DG |
329 | } |
330 | ||
331 | return ret; | |
1df4dedd DG |
332 | } |
333 | ||
334 | /* | |
335 | * lttng_kernel_disable_event | |
336 | * | |
337 | * Disable an event in the kernel tracer. | |
338 | */ | |
f3ed775e | 339 | int lttng_kernel_disable_event(char *name, char *channel_name) |
1df4dedd | 340 | { |
f3ed775e | 341 | int ret; |
1df4dedd | 342 | |
94cf3c47 | 343 | if (channel_name == NULL) { |
f3ed775e DG |
344 | strncpy(lsm.u.disable.channel_name, DEFAULT_CHANNEL_NAME, NAME_MAX); |
345 | } else { | |
346 | strncpy(lsm.u.disable.channel_name, channel_name, NAME_MAX); | |
347 | } | |
348 | ||
349 | if (name == NULL) { | |
350 | ret = ask_sessiond(LTTNG_KERNEL_DISABLE_ALL_EVENT, NULL); | |
351 | } else { | |
352 | strncpy(lsm.u.disable.name, name, NAME_MAX); | |
353 | ret = ask_sessiond(LTTNG_KERNEL_DISABLE_EVENT, NULL); | |
354 | } | |
355 | ||
356 | return ret; | |
1df4dedd DG |
357 | } |
358 | ||
359 | /* | |
f3ed775e | 360 | * lttng_kernel_enable_channel |
1df4dedd | 361 | * |
f3ed775e | 362 | * Enable recording for a channel for the kernel tracer. |
1df4dedd | 363 | */ |
f3ed775e | 364 | int lttng_kernel_enable_channel(char *name) |
1df4dedd | 365 | { |
d36b8583 | 366 | strncpy(lsm.u.enable.channel_name, name, NAME_MAX); |
f3ed775e | 367 | return ask_sessiond(LTTNG_KERNEL_ENABLE_CHANNEL, NULL); |
1df4dedd | 368 | } |
a5c5a2bd DG |
369 | |
370 | /* | |
f3ed775e | 371 | * lttng_kernel_disable_channel |
a5c5a2bd | 372 | * |
f3ed775e | 373 | * Disable recording for the channel for the kernel tracer. |
a5c5a2bd | 374 | */ |
f3ed775e | 375 | int lttng_kernel_disable_channel(char *name) |
a5c5a2bd | 376 | { |
26cc6b4e | 377 | strncpy(lsm.u.disable.channel_name, name, NAME_MAX); |
f3ed775e | 378 | return ask_sessiond(LTTNG_KERNEL_DISABLE_CHANNEL, NULL); |
a5c5a2bd | 379 | } |
8c0faa1d DG |
380 | |
381 | /* | |
f3ed775e | 382 | * lttng_kernel_create_channel |
8c0faa1d | 383 | * |
f3ed775e | 384 | * Create a channel in the kernel tracer. |
8c0faa1d | 385 | */ |
f3ed775e | 386 | int lttng_kernel_create_channel(struct lttng_channel *chan) |
8c0faa1d | 387 | { |
f3ed775e DG |
388 | memcpy(&lsm.u.channel.chan, chan, sizeof(struct lttng_channel)); |
389 | return ask_sessiond(LTTNG_KERNEL_CREATE_CHANNEL, NULL); | |
8c0faa1d | 390 | } |
1df4dedd | 391 | |
2ef84c95 | 392 | /* |
f3ed775e | 393 | * lttng_list_events |
2ef84c95 DG |
394 | * |
395 | * List all available events in the kernel. | |
396 | * | |
397 | * Return the size (bytes) of the list and set the event_list array. | |
398 | * On error, return negative value. | |
399 | */ | |
400 | int lttng_kernel_list_events(char **event_list) | |
401 | { | |
f3ed775e | 402 | return ask_sessiond(LTTNG_KERNEL_LIST_EVENTS, (void **) event_list); |
2ef84c95 DG |
403 | } |
404 | ||
1df4dedd | 405 | /* |
f3ed775e | 406 | * END Kernel control API |
1df4dedd DG |
407 | */ |
408 | ||
ca95a216 DG |
409 | /* |
410 | * lttng_get_readable_code | |
411 | * | |
412 | * Return a human readable string of code | |
413 | */ | |
414 | const char *lttng_get_readable_code(int code) | |
415 | { | |
416 | if (code > -LTTCOMM_OK) { | |
417 | return "Ended with errors"; | |
418 | } | |
419 | ||
420 | return lttcomm_get_readable_code(code); | |
421 | } | |
422 | ||
fac6795d DG |
423 | /* |
424 | * lttng_ust_list_apps | |
425 | * | |
947308c4 | 426 | * Ask the session daemon for all UST traceable applications. |
fac6795d | 427 | * |
ca95a216 DG |
428 | * Return the number of pids. |
429 | * On error, return negative value. | |
fac6795d | 430 | */ |
f3ed775e | 431 | int lttng_ust_list_traceable_apps(pid_t **pids) |
fac6795d | 432 | { |
ca95a216 | 433 | int ret; |
fac6795d | 434 | |
f3ed775e | 435 | ret = ask_sessiond(LTTNG_LIST_TRACEABLE_APPS, (void**) pids); |
fac6795d | 436 | if (ret < 0) { |
ca95a216 | 437 | return ret; |
fac6795d DG |
438 | } |
439 | ||
ca95a216 | 440 | return ret / sizeof(pid_t); |
fac6795d DG |
441 | } |
442 | ||
1657e9bb DG |
443 | /* |
444 | * lttng_list_traces | |
445 | * | |
947308c4 | 446 | * Ask the session daemon for all traces (kernel and ust) for the session |
f3ed775e | 447 | * identified by name. |
1657e9bb DG |
448 | * |
449 | * Return the number of traces. | |
947308c4 | 450 | * On error, return negative value. |
1657e9bb | 451 | */ |
f3ed775e DG |
452 | /* |
453 | int lttng_list_traces(char *session_name, struct lttng_trace **traces) | |
1657e9bb DG |
454 | { |
455 | int ret; | |
456 | ||
f3ed775e | 457 | strncpy(lsm.session_name, session_name, NAME_MAX); |
1657e9bb DG |
458 | |
459 | ret = ask_sessiond(LTTNG_LIST_TRACES, (void **) traces); | |
460 | if (ret < 0) { | |
461 | return ret; | |
462 | } | |
463 | ||
464 | return ret / sizeof(struct lttng_trace); | |
465 | } | |
f3ed775e | 466 | */ |
1657e9bb | 467 | |
aaf97519 DG |
468 | /* |
469 | * lttng_create_session | |
470 | * | |
894be886 | 471 | * Create a brand new session using name. |
aaf97519 | 472 | */ |
f3ed775e | 473 | int lttng_create_session(char *name, char *path) |
aaf97519 | 474 | { |
947308c4 | 475 | strncpy(lsm.session_name, name, NAME_MAX); |
f3ed775e | 476 | strncpy(lsm.path, path, PATH_MAX); |
947308c4 | 477 | return ask_sessiond(LTTNG_CREATE_SESSION, NULL); |
8028d920 DG |
478 | } |
479 | ||
480 | /* | |
481 | * lttng_destroy_session | |
482 | * | |
483 | * Destroy session using name. | |
484 | */ | |
f3ed775e | 485 | int lttng_destroy_session(char *name) |
8028d920 | 486 | { |
f3ed775e | 487 | strncpy(lsm.session_name, name, NAME_MAX); |
947308c4 | 488 | return ask_sessiond(LTTNG_DESTROY_SESSION, NULL); |
aaf97519 DG |
489 | } |
490 | ||
57167058 DG |
491 | /* |
492 | * lttng_list_sessions | |
493 | * | |
494 | * Ask the session daemon for all available sessions. | |
495 | * | |
ca95a216 DG |
496 | * Return number of session. |
497 | * On error, return negative value. | |
57167058 | 498 | */ |
ca95a216 | 499 | int lttng_list_sessions(struct lttng_session **sessions) |
57167058 | 500 | { |
ca95a216 | 501 | int ret; |
57167058 | 502 | |
ca95a216 | 503 | ret = ask_sessiond(LTTNG_LIST_SESSIONS, (void**) sessions); |
57167058 | 504 | if (ret < 0) { |
ca95a216 | 505 | return ret; |
57167058 DG |
506 | } |
507 | ||
ca95a216 | 508 | return ret / sizeof(struct lttng_session); |
57167058 DG |
509 | } |
510 | ||
f3ed775e | 511 | void lttng_set_session_name(char *name) |
e8be5f4f | 512 | { |
f3ed775e | 513 | strncpy(lsm.session_name, name, NAME_MAX); |
e8be5f4f DG |
514 | } |
515 | ||
fac6795d DG |
516 | /* |
517 | * lttng_set_tracing_group | |
518 | * | |
519 | * Set tracing group variable with name. This function | |
520 | * allocate memory pointed by tracing_group. | |
521 | */ | |
522 | int lttng_set_tracing_group(const char *name) | |
523 | { | |
524 | if (asprintf(&tracing_group, "%s", name) < 0) { | |
525 | return -ENOMEM; | |
526 | } | |
527 | ||
528 | return 0; | |
529 | } | |
530 | ||
531 | /* | |
532 | * lttng_check_session_daemon | |
533 | * | |
947308c4 DG |
534 | * Yes, return 1 |
535 | * No, return 0 | |
536 | * Error, return negative value | |
fac6795d | 537 | */ |
947308c4 | 538 | int lttng_session_daemon_alive(void) |
fac6795d DG |
539 | { |
540 | int ret; | |
541 | ||
542 | ret = set_session_daemon_path(); | |
543 | if (ret < 0) { | |
947308c4 | 544 | /* Error */ |
fac6795d DG |
545 | return ret; |
546 | } | |
547 | ||
548 | /* If socket exist, we consider the daemon started */ | |
549 | ret = access(sessiond_sock_path, F_OK); | |
550 | if (ret < 0) { | |
947308c4 DG |
551 | /* Not alive */ |
552 | return 0; | |
fac6795d DG |
553 | } |
554 | ||
947308c4 DG |
555 | /* Is alive */ |
556 | return 1; | |
fac6795d DG |
557 | } |
558 | ||
559 | /* | |
560 | * lib constructor | |
561 | */ | |
562 | static void __attribute__((constructor)) init() | |
563 | { | |
564 | /* Set default session group */ | |
64a23ac4 | 565 | lttng_set_tracing_group(LTTNG_DEFAULT_TRACING_GROUP); |
fac6795d | 566 | } |