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" | |
31 | ||
32 | /* Socket to session daemon for communication */ | |
33 | static int sessiond_socket; | |
34 | static char sessiond_sock_path[PATH_MAX]; | |
35 | ||
36 | /* Communication structure to ltt-sessiond */ | |
fac6795d | 37 | static struct lttcomm_session_msg lsm; |
5461b305 | 38 | static struct lttcomm_lttng_msg llm; |
fac6795d | 39 | |
fac6795d DG |
40 | /* Variables */ |
41 | static char *tracing_group; | |
42 | static int connected; | |
43 | ||
44 | /* | |
ca95a216 | 45 | * send_data_sessiond |
fac6795d | 46 | * |
e065084a | 47 | * Send lttcomm_session_msg to the session daemon. |
fac6795d DG |
48 | * |
49 | * On success, return 0 | |
50 | * On error, return error code | |
51 | */ | |
ca95a216 | 52 | static int send_data_sessiond(void) |
fac6795d DG |
53 | { |
54 | int ret; | |
55 | ||
56 | if (!connected) { | |
e065084a DG |
57 | ret = -ENOTCONN; |
58 | goto end; | |
fac6795d DG |
59 | } |
60 | ||
61 | ret = lttcomm_send_unix_sock(sessiond_socket, &lsm, sizeof(lsm)); | |
e065084a DG |
62 | |
63 | end: | |
64 | return ret; | |
65 | } | |
66 | ||
67 | /* | |
ca95a216 | 68 | * recv_data_sessiond |
e065084a DG |
69 | * |
70 | * Receive data from the sessiond socket. | |
71 | * | |
72 | * On success, return 0 | |
73 | * On error, return recv() error code | |
74 | */ | |
ca95a216 | 75 | static int recv_data_sessiond(void *buf, size_t len) |
e065084a DG |
76 | { |
77 | int ret; | |
78 | ||
79 | if (!connected) { | |
80 | ret = -ENOTCONN; | |
81 | goto end; | |
fac6795d DG |
82 | } |
83 | ||
ca95a216 | 84 | ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len); |
fac6795d | 85 | |
e065084a | 86 | end: |
fac6795d DG |
87 | return ret; |
88 | } | |
89 | ||
90 | /* | |
ca95a216 | 91 | * ask_sessiond |
fac6795d | 92 | * |
947308c4 | 93 | * Ask the session daemon a specific command and put the data into buf. |
ca95a216 DG |
94 | * |
95 | * Return size of data (only payload, not header). | |
fac6795d | 96 | */ |
6abb15de | 97 | static int ask_sessiond(enum lttcomm_sessiond_command lct, void **buf) |
fac6795d | 98 | { |
ca95a216 DG |
99 | int ret; |
100 | size_t size; | |
101 | void *data = NULL; | |
ca95a216 | 102 | |
7442b2ba DG |
103 | ret = lttng_connect_sessiond(); |
104 | if (ret < 0) { | |
105 | goto end; | |
106 | } | |
107 | ||
ca95a216 DG |
108 | lsm.cmd_type = lct; |
109 | ||
110 | /* Send command to session daemon */ | |
111 | ret = send_data_sessiond(); | |
112 | if (ret < 0) { | |
113 | goto end; | |
fac6795d DG |
114 | } |
115 | ||
ca95a216 | 116 | /* Get header from data transmission */ |
5461b305 | 117 | ret = recv_data_sessiond(&llm, sizeof(llm)); |
ca95a216 DG |
118 | if (ret < 0) { |
119 | goto end; | |
120 | } | |
fac6795d | 121 | |
ca95a216 | 122 | /* Check error code if OK */ |
5461b305 DG |
123 | if (llm.ret_code != LTTCOMM_OK) { |
124 | ret = -llm.ret_code; | |
ca95a216 DG |
125 | goto end; |
126 | } | |
fac6795d | 127 | |
5461b305 | 128 | size = llm.trace_name_offset + llm.data_size; |
ca95a216 DG |
129 | if (size == 0) { |
130 | goto end; | |
fac6795d DG |
131 | } |
132 | ||
ca95a216 DG |
133 | data = (void*) malloc(size); |
134 | ||
135 | /* Get payload data */ | |
136 | ret = recv_data_sessiond(data, size); | |
fac6795d | 137 | if (ret < 0) { |
947308c4 | 138 | free(data); |
fac6795d DG |
139 | goto end; |
140 | } | |
141 | ||
ca95a216 DG |
142 | *buf = data; |
143 | ret = size; | |
fac6795d DG |
144 | |
145 | end: | |
7442b2ba | 146 | lttng_disconnect_sessiond(); |
fac6795d DG |
147 | return ret; |
148 | } | |
149 | ||
947308c4 DG |
150 | /* |
151 | * check_tracing_group | |
152 | * | |
153 | * Check if the specified group name exist. | |
154 | * If yes, 0, else -1 | |
155 | */ | |
156 | static int check_tracing_group(const char *grp_name) | |
157 | { | |
158 | struct group *grp_tracing; /* no free(). See getgrnam(3) */ | |
159 | gid_t *grp_list; | |
160 | int grp_list_size, grp_id, i; | |
161 | int ret = -1; | |
162 | ||
163 | /* Get GID of group 'tracing' */ | |
164 | grp_tracing = getgrnam(grp_name); | |
165 | if (grp_tracing == NULL) { | |
166 | /* NULL means not found also. getgrnam(3) */ | |
167 | if (errno != 0) { | |
168 | perror("getgrnam"); | |
169 | } | |
170 | goto end; | |
171 | } | |
172 | ||
173 | /* Get number of supplementary group IDs */ | |
174 | grp_list_size = getgroups(0, NULL); | |
175 | if (grp_list_size < 0) { | |
176 | perror("getgroups"); | |
177 | goto end; | |
178 | } | |
179 | ||
180 | /* Alloc group list of the right size */ | |
181 | grp_list = malloc(grp_list_size * sizeof(gid_t)); | |
182 | grp_id = getgroups(grp_list_size, grp_list); | |
183 | if (grp_id < -1) { | |
184 | perror("getgroups"); | |
185 | goto free_list; | |
186 | } | |
187 | ||
188 | for (i = 0; i < grp_list_size; i++) { | |
189 | if (grp_list[i] == grp_tracing->gr_gid) { | |
190 | ret = 0; | |
191 | break; | |
192 | } | |
193 | } | |
194 | ||
195 | free_list: | |
196 | free(grp_list); | |
197 | ||
198 | end: | |
199 | return ret; | |
200 | } | |
201 | ||
202 | /* | |
203 | * set_session_daemon_path | |
204 | * | |
205 | * Set sessiond socket path by putting it in | |
206 | * the global sessiond_sock_path variable. | |
207 | */ | |
208 | static int set_session_daemon_path(void) | |
209 | { | |
210 | int ret; | |
211 | ||
212 | /* Are we in the tracing group ? */ | |
213 | ret = check_tracing_group(tracing_group); | |
214 | if (ret < 0 && getuid() != 0) { | |
215 | if (sprintf(sessiond_sock_path, DEFAULT_HOME_CLIENT_UNIX_SOCK, | |
216 | getenv("HOME")) < 0) { | |
217 | return -ENOMEM; | |
218 | } | |
219 | } else { | |
220 | strncpy(sessiond_sock_path, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, | |
221 | sizeof(DEFAULT_GLOBAL_CLIENT_UNIX_SOCK)); | |
222 | } | |
223 | ||
224 | return 0; | |
225 | } | |
226 | ||
1df4dedd DG |
227 | /* |
228 | * BEGIN KERNEL CONTROL | |
229 | */ | |
230 | ||
231 | /* | |
232 | * lttng_kernel_enable_event | |
233 | * | |
234 | * Enable an event in the kernel tracer. | |
235 | */ | |
236 | int lttng_kernel_enable_event(char *event_name) | |
237 | { | |
238 | strncpy(lsm.u.event.event_name, event_name, NAME_MAX); | |
239 | return ask_sessiond(KERNEL_ENABLE_EVENT, NULL); | |
240 | } | |
241 | ||
242 | /* | |
243 | * lttng_kernel_disable_event | |
244 | * | |
245 | * Disable an event in the kernel tracer. | |
246 | */ | |
247 | int lttng_kernel_disable_event(char *event_name) | |
248 | { | |
249 | strncpy(lsm.u.event.event_name, event_name, NAME_MAX); | |
250 | return ask_sessiond(KERNEL_DISABLE_EVENT, NULL); | |
251 | } | |
252 | ||
253 | /* | |
254 | * lttng_kernel_create_session | |
255 | * | |
256 | * Create a session in the kernel tracer. | |
257 | */ | |
258 | int lttng_kernel_create_session(void) | |
259 | { | |
260 | return ask_sessiond(KERNEL_CREATE_SESSION, NULL); | |
261 | } | |
262 | ||
263 | /* | |
264 | * lttng_kernel_create_channel | |
265 | * | |
266 | * Create a channel in the kernel tracer. | |
267 | */ | |
20fe2104 | 268 | int lttng_kernel_create_channel(void) |
1df4dedd | 269 | { |
1df4dedd DG |
270 | return ask_sessiond(KERNEL_CREATE_CHANNEL, NULL); |
271 | } | |
a5c5a2bd DG |
272 | |
273 | /* | |
274 | * lttng_kernel_open_metadata | |
275 | * | |
276 | * Open metadata in the kernel tracer. | |
277 | */ | |
278 | int lttng_kernel_open_metadata(void) | |
279 | { | |
280 | return ask_sessiond(KERNEL_OPEN_METADATA, NULL); | |
281 | } | |
8c0faa1d DG |
282 | |
283 | /* | |
284 | * lttng_kernel_create_stream | |
285 | * | |
286 | * Create stream in the kernel tracer. | |
287 | */ | |
288 | int lttng_kernel_create_stream(void) | |
289 | { | |
290 | return ask_sessiond(KERNEL_CREATE_STREAM, NULL); | |
291 | } | |
1df4dedd DG |
292 | |
293 | /* | |
294 | * lttng_kernel_start_tracing | |
295 | * | |
296 | * Start kernel tracing. | |
297 | */ | |
298 | int lttng_kernel_start_tracing(void) | |
299 | { | |
300 | return ask_sessiond(KERNEL_START_TRACE, NULL); | |
301 | } | |
302 | ||
303 | /* | |
304 | * lttng_kernel_stop_tracing | |
305 | * | |
306 | * Stop kernel tracing. | |
307 | */ | |
308 | int lttng_kernel_stop_tracing(void) | |
309 | { | |
310 | return ask_sessiond(KERNEL_STOP_TRACE, NULL); | |
311 | } | |
312 | ||
313 | /* | |
314 | * END KERNEL CONTROL | |
315 | */ | |
316 | ||
ca95a216 DG |
317 | /* |
318 | * lttng_get_readable_code | |
319 | * | |
320 | * Return a human readable string of code | |
321 | */ | |
322 | const char *lttng_get_readable_code(int code) | |
323 | { | |
324 | if (code > -LTTCOMM_OK) { | |
325 | return "Ended with errors"; | |
326 | } | |
327 | ||
328 | return lttcomm_get_readable_code(code); | |
329 | } | |
330 | ||
ce3d728c DG |
331 | /* |
332 | * lttng_ust_start_trace | |
333 | * | |
334 | * Request a trace start for pid. | |
335 | */ | |
336 | int lttng_ust_start_trace(pid_t pid) | |
337 | { | |
ce3d728c | 338 | lsm.pid = pid; |
947308c4 | 339 | return ask_sessiond(UST_START_TRACE, NULL); |
ce3d728c DG |
340 | } |
341 | ||
520ff687 DG |
342 | /* |
343 | * lttng_ust_stop_trace | |
344 | * | |
345 | * Request a trace stop for pid. | |
346 | */ | |
347 | int lttng_ust_stop_trace(pid_t pid) | |
348 | { | |
520ff687 | 349 | lsm.pid = pid; |
947308c4 | 350 | return ask_sessiond(UST_STOP_TRACE, NULL); |
520ff687 DG |
351 | } |
352 | ||
df0da139 DG |
353 | /* |
354 | * lttng_ust_create_trace | |
355 | * | |
356 | * Request a trace creation for pid. | |
357 | */ | |
358 | int lttng_ust_create_trace(pid_t pid) | |
359 | { | |
df0da139 | 360 | lsm.pid = pid; |
947308c4 | 361 | return ask_sessiond(UST_CREATE_TRACE, NULL); |
df0da139 DG |
362 | } |
363 | ||
fac6795d DG |
364 | /* |
365 | * lttng_ust_list_apps | |
366 | * | |
947308c4 | 367 | * Ask the session daemon for all UST traceable applications. |
fac6795d | 368 | * |
ca95a216 DG |
369 | * Return the number of pids. |
370 | * On error, return negative value. | |
fac6795d | 371 | */ |
ca95a216 | 372 | int lttng_ust_list_apps(pid_t **pids) |
fac6795d | 373 | { |
ca95a216 | 374 | int ret; |
fac6795d | 375 | |
ca95a216 | 376 | ret = ask_sessiond(UST_LIST_APPS, (void**) pids); |
fac6795d | 377 | if (ret < 0) { |
ca95a216 | 378 | return ret; |
fac6795d DG |
379 | } |
380 | ||
ca95a216 | 381 | return ret / sizeof(pid_t); |
fac6795d DG |
382 | } |
383 | ||
1657e9bb DG |
384 | /* |
385 | * lttng_list_traces | |
386 | * | |
947308c4 DG |
387 | * Ask the session daemon for all traces (kernel and ust) for the session |
388 | * identified by uuid. | |
1657e9bb DG |
389 | * |
390 | * Return the number of traces. | |
947308c4 | 391 | * On error, return negative value. |
1657e9bb DG |
392 | */ |
393 | int lttng_list_traces(uuid_t *uuid, struct lttng_trace **traces) | |
394 | { | |
395 | int ret; | |
396 | ||
5461b305 | 397 | uuid_copy(lsm.session_uuid, *uuid); |
1657e9bb DG |
398 | |
399 | ret = ask_sessiond(LTTNG_LIST_TRACES, (void **) traces); | |
400 | if (ret < 0) { | |
401 | return ret; | |
402 | } | |
403 | ||
404 | return ret / sizeof(struct lttng_trace); | |
405 | } | |
406 | ||
aaf97519 DG |
407 | /* |
408 | * lttng_create_session | |
409 | * | |
894be886 | 410 | * Create a brand new session using name. |
aaf97519 | 411 | */ |
894be886 | 412 | int lttng_create_session(char *name) |
aaf97519 | 413 | { |
947308c4 DG |
414 | strncpy(lsm.session_name, name, NAME_MAX); |
415 | return ask_sessiond(LTTNG_CREATE_SESSION, NULL); | |
8028d920 DG |
416 | } |
417 | ||
418 | /* | |
419 | * lttng_destroy_session | |
420 | * | |
421 | * Destroy session using name. | |
422 | */ | |
423 | int lttng_destroy_session(uuid_t *uuid) | |
424 | { | |
5461b305 | 425 | uuid_copy(lsm.session_uuid, *uuid); |
947308c4 | 426 | return ask_sessiond(LTTNG_DESTROY_SESSION, NULL); |
aaf97519 DG |
427 | } |
428 | ||
57167058 DG |
429 | /* |
430 | * lttng_list_sessions | |
431 | * | |
432 | * Ask the session daemon for all available sessions. | |
433 | * | |
ca95a216 DG |
434 | * Return number of session. |
435 | * On error, return negative value. | |
57167058 | 436 | */ |
ca95a216 | 437 | int lttng_list_sessions(struct lttng_session **sessions) |
57167058 | 438 | { |
ca95a216 | 439 | int ret; |
57167058 | 440 | |
ca95a216 | 441 | ret = ask_sessiond(LTTNG_LIST_SESSIONS, (void**) sessions); |
57167058 | 442 | if (ret < 0) { |
ca95a216 | 443 | return ret; |
57167058 DG |
444 | } |
445 | ||
ca95a216 | 446 | return ret / sizeof(struct lttng_session); |
57167058 DG |
447 | } |
448 | ||
fac6795d DG |
449 | /* |
450 | * lttng_connect_sessiond | |
451 | * | |
452 | * Connect to the LTTng session daemon. | |
453 | * On success, return 0 | |
454 | * On error, return a negative value | |
455 | */ | |
456 | int lttng_connect_sessiond(void) | |
457 | { | |
458 | int ret; | |
459 | ||
460 | ret = set_session_daemon_path(); | |
461 | if (ret < 0) { | |
462 | return ret; | |
463 | } | |
464 | ||
465 | /* Connect to the sesssion daemon */ | |
466 | ret = lttcomm_connect_unix_sock(sessiond_sock_path); | |
467 | if (ret < 0) { | |
468 | return ret; | |
469 | } | |
470 | ||
471 | sessiond_socket = ret; | |
472 | connected = 1; | |
473 | ||
474 | return 0; | |
475 | } | |
476 | ||
87378cf5 DG |
477 | /* |
478 | * lttng_disconnect_sessiond | |
479 | * | |
480 | * Clean disconnect the session daemon. | |
481 | */ | |
482 | int lttng_disconnect_sessiond(void) | |
483 | { | |
484 | int ret = 0; | |
485 | ||
486 | if (connected) { | |
487 | ret = lttcomm_close_unix_sock(sessiond_socket); | |
488 | sessiond_socket = 0; | |
489 | connected = 0; | |
490 | } | |
491 | ||
492 | return ret; | |
493 | } | |
494 | ||
e8be5f4f DG |
495 | /* |
496 | * lttng_set_current_session_uuid | |
497 | * | |
498 | * Set the session uuid for current lsm. | |
499 | */ | |
96243366 | 500 | void lttng_set_current_session_uuid(uuid_t *uuid) |
e8be5f4f | 501 | { |
5461b305 | 502 | uuid_copy(lsm.session_uuid, *uuid); |
e8be5f4f DG |
503 | } |
504 | ||
fac6795d DG |
505 | /* |
506 | * lttng_set_tracing_group | |
507 | * | |
508 | * Set tracing group variable with name. This function | |
509 | * allocate memory pointed by tracing_group. | |
510 | */ | |
511 | int lttng_set_tracing_group(const char *name) | |
512 | { | |
513 | if (asprintf(&tracing_group, "%s", name) < 0) { | |
514 | return -ENOMEM; | |
515 | } | |
516 | ||
517 | return 0; | |
518 | } | |
519 | ||
520 | /* | |
521 | * lttng_check_session_daemon | |
522 | * | |
947308c4 DG |
523 | * Yes, return 1 |
524 | * No, return 0 | |
525 | * Error, return negative value | |
fac6795d | 526 | */ |
947308c4 | 527 | int lttng_session_daemon_alive(void) |
fac6795d DG |
528 | { |
529 | int ret; | |
530 | ||
531 | ret = set_session_daemon_path(); | |
532 | if (ret < 0) { | |
947308c4 | 533 | /* Error */ |
fac6795d DG |
534 | return ret; |
535 | } | |
536 | ||
537 | /* If socket exist, we consider the daemon started */ | |
538 | ret = access(sessiond_sock_path, F_OK); | |
539 | if (ret < 0) { | |
947308c4 DG |
540 | /* Not alive */ |
541 | return 0; | |
fac6795d DG |
542 | } |
543 | ||
947308c4 DG |
544 | /* Is alive */ |
545 | return 1; | |
fac6795d DG |
546 | } |
547 | ||
548 | /* | |
549 | * lib constructor | |
550 | */ | |
551 | static void __attribute__((constructor)) init() | |
552 | { | |
553 | /* Set default session group */ | |
64a23ac4 | 554 | lttng_set_tracing_group(LTTNG_DEFAULT_TRACING_GROUP); |
fac6795d | 555 | } |