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 modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (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 along | |
15 | * with this program; if not, write to the Free Software Foundation, Inc., | |
16 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
fac6795d DG |
17 | */ |
18 | ||
19 | #define _GNU_SOURCE | |
20 | #include <errno.h> | |
21 | #include <fcntl.h> | |
22 | #include <getopt.h> | |
23 | #include <grp.h> | |
24 | #include <limits.h> | |
25 | #include <stdio.h> | |
26 | #include <stdlib.h> | |
27 | #include <string.h> | |
28 | #include <sys/stat.h> | |
29 | #include <sys/types.h> | |
30 | #include <sys/wait.h> | |
31 | #include <unistd.h> | |
32 | ||
5b97ec60 | 33 | #include <lttng/lttng.h> |
fac6795d DG |
34 | |
35 | #include "lttng.h" | |
36 | #include "lttngerr.h" | |
37 | ||
38 | /* Variables */ | |
39 | static char *progname; | |
40 | ||
41 | /* Prototypes */ | |
42 | static int process_client_opt(void); | |
43 | static int process_opt_list_apps(void); | |
57167058 | 44 | static int process_opt_list_sessions(void); |
1657e9bb | 45 | static int process_opt_list_traces(void); |
aaf97519 | 46 | static int process_opt_create_session(void); |
5b8719f5 DG |
47 | static void sighandler(int sig); |
48 | static int set_signal_handler(void); | |
8548ff30 | 49 | static int validate_options(void); |
47b74d63 | 50 | static char *get_cmdline_by_pid(pid_t pid); |
fac6795d DG |
51 | |
52 | /* | |
53 | * start_client | |
54 | * | |
55 | * Process client request from the command line | |
56 | * options. Every tracing action is done by the | |
57 | * liblttngctl API. | |
58 | */ | |
59 | static int process_client_opt(void) | |
60 | { | |
61 | int ret; | |
8028d920 | 62 | uuid_t uuid; |
fac6795d DG |
63 | |
64 | /* Connect to the session daemon */ | |
65 | ret = lttng_connect_sessiond(); | |
66 | if (ret < 0) { | |
fac6795d DG |
67 | goto end; |
68 | } | |
69 | ||
70 | if (opt_list_apps) { | |
71 | ret = process_opt_list_apps(); | |
72 | if (ret < 0) { | |
fac6795d DG |
73 | goto end; |
74 | } | |
75 | } | |
76 | ||
57167058 DG |
77 | if (opt_list_session) { |
78 | ret = process_opt_list_sessions(); | |
79 | if (ret < 0) { | |
80 | goto end; | |
81 | } | |
82 | } | |
83 | ||
1657e9bb DG |
84 | if (opt_list_traces) { |
85 | ret = process_opt_list_traces(); | |
86 | if (ret < 0) { | |
87 | goto end; | |
88 | } | |
89 | } | |
90 | ||
aaf97519 DG |
91 | if (opt_create_session != NULL) { |
92 | ret = process_opt_create_session(); | |
93 | if (ret < 0) { | |
94 | goto end; | |
95 | } | |
96 | } | |
97 | ||
8028d920 DG |
98 | if (opt_destroy_session != NULL) { |
99 | uuid_parse(opt_destroy_session, uuid); | |
100 | ret = lttng_destroy_session(&uuid); | |
101 | if (ret < 0) { | |
102 | goto end; | |
103 | } | |
104 | } | |
105 | ||
e8be5f4f | 106 | if (opt_session_uuid != NULL) { |
ce3d728c | 107 | DBG("Set session uuid to %s", opt_session_uuid); |
e8be5f4f DG |
108 | lttng_set_current_session_uuid(opt_session_uuid); |
109 | } | |
110 | ||
ad874cce DG |
111 | if (opt_trace_kernel) { |
112 | ERR("Not implemented yet"); | |
113 | goto end; | |
df0da139 DG |
114 | } |
115 | ||
ad874cce DG |
116 | if (opt_trace_pid != 0) { |
117 | if (opt_create_trace) { | |
118 | DBG("Create a userspace trace for pid %d", opt_trace_pid); | |
119 | ret = lttng_ust_create_trace(opt_trace_pid); | |
120 | if (ret < 0) { | |
121 | goto end; | |
122 | } | |
123 | MSG("Trace created successfully!\nUse --start to start tracing."); | |
ce3d728c | 124 | } |
ce3d728c | 125 | |
ad874cce DG |
126 | if (opt_start_trace) { |
127 | DBG("Start trace for pid %d", opt_trace_pid); | |
128 | ret = lttng_ust_start_trace(opt_trace_pid); | |
129 | if (ret < 0) { | |
130 | goto end; | |
131 | } | |
132 | MSG("Trace started successfully!"); | |
133 | } else if (opt_stop_trace) { | |
134 | DBG("Stop trace for pid %d", opt_trace_pid); | |
135 | ret = lttng_ust_stop_trace(opt_trace_pid); | |
136 | if (ret < 0) { | |
137 | goto end; | |
138 | } | |
139 | MSG("Trace stopped successfully!"); | |
520ff687 | 140 | } |
ad874cce | 141 | |
520ff687 DG |
142 | } |
143 | ||
fac6795d DG |
144 | return 0; |
145 | ||
146 | end: | |
ebafd2a5 | 147 | ERR("%s", lttng_get_readable_code(ret)); |
fac6795d DG |
148 | return ret; |
149 | } | |
150 | ||
1657e9bb DG |
151 | /* |
152 | * process_opt_list_traces | |
153 | * | |
154 | * Get list of all traces for a specific session uuid. | |
155 | */ | |
156 | static int process_opt_list_traces(void) | |
157 | { | |
158 | int ret, i; | |
159 | uuid_t uuid; | |
160 | struct lttng_trace *traces; | |
161 | ||
162 | uuid_parse(opt_session_uuid, uuid); | |
163 | ret = lttng_list_traces(&uuid, &traces); | |
164 | if (ret < 0) { | |
165 | goto error; | |
166 | } | |
167 | ||
168 | MSG("Userspace traces:"); | |
169 | for (i = 0; i < ret; i++) { | |
170 | if (traces[i].type == USERSPACE) { | |
47b74d63 DG |
171 | MSG("\t%d) %s (pid: %d): %s", |
172 | i, traces[i].name, traces[i].pid, | |
173 | get_cmdline_by_pid(traces[i].pid)); | |
1657e9bb DG |
174 | } else { |
175 | break; | |
176 | } | |
177 | } | |
178 | ||
179 | MSG("Kernel traces:"); | |
180 | for (;i < ret; i++) { | |
181 | if (traces[i].type == KERNEL) { | |
182 | MSG("\t%d) %s", i, traces[i].name); | |
183 | } | |
184 | } | |
185 | ||
186 | free(traces); | |
187 | ||
188 | error: | |
189 | return ret; | |
190 | } | |
191 | ||
aaf97519 DG |
192 | /* |
193 | * process_opt_create_session | |
194 | * | |
195 | * Create a new session using the name pass | |
196 | * to the command line. | |
197 | */ | |
198 | static int process_opt_create_session(void) | |
199 | { | |
200 | int ret; | |
8028d920 DG |
201 | uuid_t session_id; |
202 | char str_uuid[37]; | |
aaf97519 DG |
203 | |
204 | ret = lttng_create_session(opt_create_session, &session_id); | |
205 | if (ret < 0) { | |
206 | goto error; | |
207 | } | |
208 | ||
8028d920 DG |
209 | uuid_unparse(session_id, str_uuid); |
210 | ||
aaf97519 | 211 | MSG("Session created:"); |
8028d920 | 212 | MSG(" %s (%s)", opt_create_session, str_uuid); |
aaf97519 DG |
213 | |
214 | error: | |
215 | return ret; | |
216 | } | |
217 | ||
57167058 DG |
218 | /* |
219 | * process_opt_list_sessions | |
220 | * | |
221 | * Get the list of available sessions from | |
222 | * the session daemon and print it to user. | |
223 | */ | |
224 | static int process_opt_list_sessions(void) | |
225 | { | |
226 | int ret, count, i; | |
227 | struct lttng_session *sess; | |
228 | ||
229 | count = lttng_list_sessions(&sess); | |
230 | if (count < 0) { | |
231 | ret = count; | |
232 | goto error; | |
233 | } | |
234 | ||
235 | MSG("Available sessions [Name (uuid)]:"); | |
236 | for (i = 0; i < count; i++) { | |
237 | MSG("\tName: %s (uuid: %s)", sess[i].name, sess[i].uuid); | |
238 | } | |
239 | ||
240 | free(sess); | |
241 | MSG("\nTo select a session, use --session UUID."); | |
242 | ||
243 | return 0; | |
244 | ||
245 | error: | |
246 | return ret; | |
247 | } | |
248 | ||
fac6795d DG |
249 | /* |
250 | * process_opt_list_apps | |
251 | * | |
252 | * Get the UST traceable pid list and print | |
253 | * them to the user. | |
254 | */ | |
255 | static int process_opt_list_apps(void) | |
256 | { | |
e8f07c63 | 257 | int i, ret, count; |
fac6795d | 258 | pid_t *pids; |
1c9f7941 | 259 | char *cmdline; |
fac6795d | 260 | |
e8f07c63 DG |
261 | count = lttng_ust_list_apps(&pids); |
262 | if (count < 0) { | |
263 | ret = count; | |
fac6795d DG |
264 | goto error; |
265 | } | |
266 | ||
267 | MSG("LTTng UST traceable application [name (pid)]:"); | |
e8f07c63 | 268 | for (i=0; i < count; i++) { |
47b74d63 DG |
269 | cmdline = get_cmdline_by_pid(pids[i]); |
270 | if (cmdline == NULL) { | |
e8f07c63 | 271 | MSG("\t(not running) (%d)", pids[i]); |
fac6795d DG |
272 | continue; |
273 | } | |
fac6795d | 274 | MSG("\t%s (%d)", cmdline, pids[i]); |
1c9f7941 | 275 | free(cmdline); |
fac6795d DG |
276 | } |
277 | ||
e065084a DG |
278 | /* Allocated by lttng_ust_list_apps() */ |
279 | free(pids); | |
280 | ||
fac6795d DG |
281 | return 0; |
282 | ||
283 | error: | |
284 | return ret; | |
285 | } | |
286 | ||
1c9f7941 DG |
287 | /* |
288 | * get_cmdline_by_pid | |
289 | * | |
47b74d63 | 290 | * Get command line from /proc for a specific pid. |
1c9f7941 | 291 | * |
47b74d63 DG |
292 | * On success, return an allocated string pointer pointing to |
293 | * the proc cmdline. | |
294 | * On error, return NULL. | |
1c9f7941 | 295 | */ |
47b74d63 | 296 | static char *get_cmdline_by_pid(pid_t pid) |
1c9f7941 DG |
297 | { |
298 | int ret; | |
299 | FILE *fp; | |
47b74d63 | 300 | char *cmdline = NULL; |
1c9f7941 DG |
301 | char path[24]; /* Can't go bigger than /proc/65535/cmdline */ |
302 | ||
303 | snprintf(path, sizeof(path), "/proc/%d/cmdline", pid); | |
304 | fp = fopen(path, "r"); | |
305 | if (fp == NULL) { | |
47b74d63 | 306 | goto end; |
1c9f7941 DG |
307 | } |
308 | ||
309 | /* Caller must free() *cmdline */ | |
47b74d63 DG |
310 | cmdline = malloc(PATH_MAX); |
311 | ret = fread(cmdline, 1, PATH_MAX, fp); | |
1c9f7941 DG |
312 | fclose(fp); |
313 | ||
47b74d63 DG |
314 | end: |
315 | return cmdline; | |
1c9f7941 DG |
316 | } |
317 | ||
8548ff30 DG |
318 | /* |
319 | * validate_options | |
320 | * | |
321 | * Make sure that all options passed to the command line | |
322 | * are compatible with each others. | |
323 | * | |
324 | * On error, return -1 | |
325 | * On success, return 0 | |
326 | */ | |
327 | static int validate_options(void) | |
328 | { | |
ad874cce DG |
329 | /* Conflicting command */ |
330 | if (opt_start_trace && opt_stop_trace) { | |
331 | ERR("Can't use --start and --stop together."); | |
332 | goto error; | |
333 | /* Must have a session UUID for trace action. */ | |
334 | } else if ((opt_session_uuid == NULL) && | |
335 | (opt_create_trace || opt_start_trace || opt_stop_trace || opt_list_traces)) { | |
1657e9bb | 336 | ERR("You need to specify a session UUID.\nPlease use --session UUID to do so."); |
8548ff30 | 337 | goto error; |
ad874cce DG |
338 | /* If no PID specified and trace_kernel is off */ |
339 | } else if ((opt_trace_pid == 0 && opt_trace_kernel == 0) && | |
340 | (opt_create_trace || opt_start_trace || opt_stop_trace)) { | |
341 | ERR("Please specify a PID using -p, --pid PID."); | |
342 | goto error; | |
8548ff30 DG |
343 | } |
344 | ||
345 | return 0; | |
346 | ||
347 | error: | |
348 | return -1; | |
349 | } | |
350 | ||
5b8719f5 DG |
351 | /* |
352 | * spawn_sessiond | |
353 | * | |
354 | * Spawn a session daemon by forking and execv. | |
355 | */ | |
356 | static int spawn_sessiond(char *pathname) | |
357 | { | |
358 | int ret = 0; | |
359 | pid_t pid; | |
360 | ||
361 | MSG("Spawning session daemon"); | |
362 | pid = fork(); | |
363 | if (pid == 0) { | |
364 | /* Spawn session daemon and tell | |
365 | * it to signal us when ready. | |
366 | */ | |
75462a81 | 367 | ret = execlp(pathname, "ltt-sessiond", "--sig-parent", "--quiet", NULL); |
5b8719f5 DG |
368 | if (ret < 0) { |
369 | if (errno == ENOENT) { | |
370 | ERR("No session daemon found. Use --sessiond-path."); | |
371 | } else { | |
372 | perror("execlp"); | |
373 | } | |
374 | kill(getppid(), SIGTERM); | |
375 | exit(EXIT_FAILURE); | |
376 | } | |
377 | exit(EXIT_SUCCESS); | |
378 | } else if (pid > 0) { | |
379 | /* Wait for ltt-sessiond to start */ | |
380 | pause(); | |
381 | goto end; | |
382 | } else { | |
383 | perror("fork"); | |
384 | ret = -1; | |
385 | goto end; | |
386 | } | |
387 | ||
388 | end: | |
389 | return ret; | |
390 | } | |
391 | ||
fac6795d DG |
392 | /* |
393 | * check_ltt_sessiond | |
394 | * | |
395 | * Check if the session daemon is available using | |
5b8719f5 DG |
396 | * the liblttngctl API for the check. If not, try to |
397 | * spawn a daemon. | |
fac6795d DG |
398 | */ |
399 | static int check_ltt_sessiond(void) | |
400 | { | |
401 | int ret; | |
5b8719f5 | 402 | char *pathname = NULL; |
fac6795d DG |
403 | |
404 | ret = lttng_check_session_daemon(); | |
405 | if (ret < 0) { | |
5b8719f5 DG |
406 | /* Try command line option path */ |
407 | if (opt_sessiond_path != NULL) { | |
408 | ret = access(opt_sessiond_path, F_OK | X_OK); | |
409 | if (ret < 0) { | |
410 | ERR("No such file: %s", opt_sessiond_path); | |
411 | goto end; | |
412 | } | |
413 | pathname = opt_sessiond_path; | |
414 | } else { | |
415 | /* Try LTTNG_SESSIOND_PATH env variable */ | |
e8f07c63 DG |
416 | pathname = getenv(LTTNG_SESSIOND_PATH_ENV); |
417 | if (pathname != NULL) { | |
418 | /* strdup here in order to make the free() | |
419 | * not fail later on. | |
420 | */ | |
421 | pathname = strdup(pathname); | |
422 | } | |
5b8719f5 DG |
423 | } |
424 | ||
425 | /* Let's rock and roll */ | |
426 | if (pathname == NULL) { | |
427 | ret = asprintf(&pathname, "ltt-sessiond"); | |
428 | if (ret < 0) { | |
429 | goto end; | |
430 | } | |
431 | } | |
432 | ||
433 | ret = spawn_sessiond(pathname); | |
434 | free(pathname); | |
435 | if (ret < 0) { | |
436 | ERR("Problem occurs when starting %s", pathname); | |
437 | goto end; | |
438 | } | |
fac6795d DG |
439 | } |
440 | ||
5b8719f5 | 441 | end: |
fac6795d DG |
442 | return ret; |
443 | } | |
444 | ||
5b8719f5 DG |
445 | /* |
446 | * set_signal_handler | |
447 | * | |
448 | * Setup signal handler for SIGCHLD and SIGTERM. | |
449 | */ | |
450 | static int set_signal_handler(void) | |
451 | { | |
452 | int ret = 0; | |
453 | struct sigaction sa; | |
454 | sigset_t sigset; | |
455 | ||
456 | if ((ret = sigemptyset(&sigset)) < 0) { | |
457 | perror("sigemptyset"); | |
458 | goto end; | |
459 | } | |
460 | ||
461 | sa.sa_handler = sighandler; | |
462 | sa.sa_mask = sigset; | |
463 | sa.sa_flags = 0; | |
464 | if ((ret = sigaction(SIGCHLD, &sa, NULL)) < 0) { | |
465 | perror("sigaction"); | |
466 | goto end; | |
467 | } | |
fac6795d | 468 | |
5b8719f5 DG |
469 | if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { |
470 | perror("sigaction"); | |
471 | goto end; | |
472 | } | |
473 | ||
474 | end: | |
475 | return ret; | |
476 | } | |
477 | ||
478 | /* | |
479 | * sighandler | |
480 | * | |
481 | * Signal handler for the daemon | |
482 | */ | |
483 | static void sighandler(int sig) | |
484 | { | |
5b8719f5 DG |
485 | switch (sig) { |
486 | case SIGTERM: | |
ce3d728c | 487 | DBG("SIGTERM catched"); |
5b8719f5 DG |
488 | clean_exit(EXIT_FAILURE); |
489 | break; | |
490 | case SIGCHLD: | |
491 | /* Notify is done */ | |
ce3d728c | 492 | DBG("SIGCHLD catched"); |
5b8719f5 DG |
493 | break; |
494 | default: | |
ce3d728c | 495 | DBG("Unknown signal %d catched", sig); |
5b8719f5 DG |
496 | break; |
497 | } | |
498 | ||
499 | return; | |
500 | } | |
fac6795d DG |
501 | /* |
502 | * clean_exit | |
503 | */ | |
504 | void clean_exit(int code) | |
505 | { | |
506 | DBG("Clean exit"); | |
87378cf5 DG |
507 | if (lttng_disconnect_sessiond() < 0) { |
508 | ERR("Session daemon disconnect failed."); | |
509 | } | |
fac6795d DG |
510 | exit(code); |
511 | } | |
512 | ||
513 | /* | |
5b8719f5 | 514 | * main |
fac6795d DG |
515 | */ |
516 | int main(int argc, char *argv[]) | |
517 | { | |
518 | int ret; | |
519 | ||
520 | progname = argv[0] ? argv[0] : "lttng"; | |
521 | ||
522 | /* For Mathieu Desnoyers aka Dr Tracing */ | |
523 | if (strncmp(progname, "drtrace", 7) == 0) { | |
524 | MSG("%c[%d;%dmWelcome back Dr Tracing!%c[%dm\n\n", 27,1,33,27,0); | |
525 | } | |
526 | ||
527 | ret = parse_args(argc, (const char **) argv); | |
528 | if (ret < 0) { | |
87378cf5 | 529 | clean_exit(EXIT_FAILURE); |
fac6795d DG |
530 | } |
531 | ||
8548ff30 DG |
532 | ret = validate_options(); |
533 | if (ret < 0) { | |
534 | return EXIT_FAILURE; | |
535 | } | |
536 | ||
5b8719f5 DG |
537 | ret = set_signal_handler(); |
538 | if (ret < 0) { | |
87378cf5 | 539 | clean_exit(ret); |
5b8719f5 DG |
540 | } |
541 | ||
fac6795d DG |
542 | if (opt_tracing_group != NULL) { |
543 | DBG("Set tracing group to '%s'", opt_tracing_group); | |
544 | lttng_set_tracing_group(opt_tracing_group); | |
545 | } | |
546 | ||
547 | /* If ask for kernel tracing, need root perms */ | |
548 | if (opt_trace_kernel) { | |
549 | DBG("Kernel tracing activated"); | |
550 | if (getuid() != 0) { | |
551 | ERR("%s must be setuid root", progname); | |
87378cf5 | 552 | clean_exit(-EPERM); |
fac6795d DG |
553 | } |
554 | } | |
555 | ||
556 | /* Check if the lttng session daemon is running. | |
557 | * If no, a daemon will be spawned. | |
558 | */ | |
5b8719f5 | 559 | if (opt_no_sessiond == 0 && (check_ltt_sessiond() < 0)) { |
87378cf5 | 560 | clean_exit(EXIT_FAILURE); |
fac6795d DG |
561 | } |
562 | ||
563 | ret = process_client_opt(); | |
564 | if (ret < 0) { | |
87378cf5 | 565 | clean_exit(ret); |
fac6795d DG |
566 | } |
567 | ||
87378cf5 DG |
568 | clean_exit(0); |
569 | ||
fac6795d DG |
570 | return 0; |
571 | } |