Close client socket in sessiond
[lttng-tools.git] / ltt-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
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.
17 */
18
19 #define _GNU_SOURCE
20 #include <fcntl.h>
21 #include <getopt.h>
22 #include <grp.h>
23 #include <limits.h>
24 #include <pthread.h>
25 #include <semaphore.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sys/ipc.h>
31 #include <sys/shm.h>
32 #include <sys/socket.h>
33 #include <sys/stat.h>
34 #include <sys/types.h>
35 #include <unistd.h>
36
37 #include <urcu/list.h> /* URCU list library (-lurcu) */
38 #include <ust/ustctl.h> /* UST control lib (-lust) */
39 #include <lttng/lttng.h>
40
41 #include "liblttsessiondcomm.h"
42 #include "ltt-sessiond.h"
43 #include "lttngerr.h"
44 #include "kernel-ctl.h"
45 #include "ust-ctl.h"
46 #include "session.h"
47 #include "traceable-app.h"
48 #include "lttng-kconsumerd.h"
49
50 /*
51 * TODO:
52 * teardown: signal SIGTERM handler -> write into pipe. Threads waits
53 * with epoll on pipe and on other pipes/sockets for commands. Main
54 * simply waits on pthread join.
55 */
56
57 /* Const values */
58 const char default_home_dir[] = DEFAULT_HOME_DIR;
59 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
60 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
61 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
62
63 /* Variables */
64 int opt_verbose; /* Not static for lttngerr.h */
65 int opt_quiet; /* Not static for lttngerr.h */
66 const char *progname;
67 const char *opt_tracing_group;
68 static int opt_sig_parent;
69 static int opt_daemon;
70 static int is_root; /* Set to 1 if the daemon is running as root */
71 static pid_t ppid; /* Parent PID for --sig-parent option */
72 static pid_t kconsumerd_pid;
73
74 static char apps_unix_sock_path[PATH_MAX]; /* Global application Unix socket path */
75 static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */
76 static char kconsumerd_err_unix_sock_path[PATH_MAX]; /* kconsumerd error Unix socket path */
77 static char kconsumerd_cmd_unix_sock_path[PATH_MAX]; /* kconsumerd command Unix socket path */
78
79 /* Sockets and FDs */
80 static int client_sock;
81 static int apps_sock;
82 static int kconsumerd_err_sock;
83 static int kconsumerd_cmd_sock;
84 static int kernel_tracer_fd;
85
86 /* Pthread, Mutexes and Semaphores */
87 static pthread_t kconsumerd_thread;
88 static pthread_t apps_thread;
89 static pthread_t client_thread;
90 static sem_t kconsumerd_sem;
91
92 static pthread_mutex_t kconsumerd_pid_mutex; /* Mutex to control kconsumerd pid assignation */
93
94 /*
95 * teardown_kernel_session
96 *
97 * Complete teardown of a kernel session. This free all data structure
98 * related to a kernel session and update counter.
99 */
100 static void teardown_kernel_session(struct ltt_session *session)
101 {
102 if (session->kernel_session != NULL) {
103 DBG("Tearing down kernel session");
104 trace_destroy_kernel_session(session->kernel_session);
105 /* Extra precaution */
106 session->kernel_session = NULL;
107 /* Decrement session count */
108 session->kern_session_count--;
109 }
110 }
111
112 /*
113 * cleanup
114 *
115 * Cleanup the daemon on exit
116 */
117 static void cleanup()
118 {
119 int ret;
120 char *cmd;
121 struct ltt_session *sess;
122
123 DBG("Cleaning up");
124
125 /* <fun> */
126 MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
127 MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0);
128 /* </fun> */
129
130 /* Stopping all threads */
131 DBG("Terminating all threads");
132 pthread_cancel(client_thread);
133 pthread_cancel(apps_thread);
134 if (kconsumerd_pid != 0) {
135 pthread_cancel(kconsumerd_thread);
136 }
137
138 DBG("Unlinking all unix socket");
139 unlink(client_unix_sock_path);
140 unlink(apps_unix_sock_path);
141 unlink(kconsumerd_err_unix_sock_path);
142
143 DBG("Removing %s directory", LTTNG_RUNDIR);
144 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
145 if (ret < 0) {
146 ERR("asprintf failed. Something is really wrong!");
147 }
148
149 /* Remove lttng run directory */
150 ret = system(cmd);
151 if (ret < 0) {
152 ERR("Unable to clean " LTTNG_RUNDIR);
153 }
154
155 DBG("Cleaning up all session");
156 /* Cleanup ALL session */
157 cds_list_for_each_entry(sess, &ltt_session_list.head, list) {
158 teardown_kernel_session(sess);
159 // TODO complete session cleanup (including UST)
160 }
161
162 close(kernel_tracer_fd);
163 }
164
165 /*
166 * send_unix_sock
167 *
168 * Send data on a unix socket using the liblttsessiondcomm API.
169 *
170 * Return lttcomm error code.
171 */
172 static int send_unix_sock(int sock, void *buf, size_t len)
173 {
174 /* Check valid length */
175 if (len <= 0) {
176 return -1;
177 }
178
179 return lttcomm_send_unix_sock(sock, buf, len);
180 }
181
182 /*
183 * clean_command_ctx
184 *
185 * Free memory of a command context structure.
186 */
187 static void clean_command_ctx(struct command_ctx *cmd_ctx)
188 {
189 DBG("Clean command context structure %p", cmd_ctx);
190 if (cmd_ctx) {
191 if (cmd_ctx->llm) {
192 free(cmd_ctx->llm);
193 }
194 if (cmd_ctx->lsm) {
195 free(cmd_ctx->lsm);
196 }
197 free(cmd_ctx);
198 cmd_ctx = NULL;
199 }
200 }
201
202 /*
203 * ust_connect_app
204 *
205 * Return a socket connected to the libust communication socket
206 * of the application identified by the pid.
207 *
208 * If the pid is not found in the traceable list,
209 * return -1 to indicate error.
210 */
211 static int ust_connect_app(pid_t pid)
212 {
213 int sock;
214 struct ltt_traceable_app *lta;
215
216 DBG("Connect to application pid %d", pid);
217
218 lta = find_app_by_pid(pid);
219 if (lta == NULL) {
220 /* App not found */
221 DBG("Application pid %d not found", pid);
222 return -1;
223 }
224
225 sock = ustctl_connect_pid(lta->pid);
226 if (sock < 0) {
227 ERR("Fail connecting to the PID %d\n", pid);
228 }
229
230 return sock;
231 }
232
233 /*
234 * notify_apps
235 *
236 * Notify apps by writing 42 to a named pipe using name.
237 * Every applications waiting for a ltt-sessiond will be notified
238 * and re-register automatically to the session daemon.
239 *
240 * Return open or write error value.
241 */
242 static int notify_apps(const char *name)
243 {
244 int fd;
245 int ret = -1;
246
247 DBG("Notify the global application pipe");
248
249 /* Try opening the global pipe */
250 fd = open(name, O_WRONLY);
251 if (fd < 0) {
252 goto error;
253 }
254
255 /* Notify by writing on the pipe */
256 ret = write(fd, "42", 2);
257 if (ret < 0) {
258 perror("write");
259 }
260
261 error:
262 return ret;
263 }
264
265 /*
266 * setup_lttng_msg
267 *
268 * Setup the outgoing data buffer for the response (llm) by allocating the
269 * right amount of memory and copying the original information from the lsm
270 * structure.
271 *
272 * Return total size of the buffer pointed by buf.
273 */
274 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
275 {
276 int ret, buf_size, trace_name_size;
277
278 /*
279 * Check for the trace_name. If defined, it's part of the payload data of
280 * the llm structure.
281 */
282 trace_name_size = strlen(cmd_ctx->lsm->trace_name);
283 buf_size = trace_name_size + size;
284
285 cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
286 if (cmd_ctx->llm == NULL) {
287 perror("malloc");
288 ret = -ENOMEM;
289 goto error;
290 }
291
292 /* Copy common data */
293 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
294 cmd_ctx->llm->pid = cmd_ctx->lsm->pid;
295 if (!uuid_is_null(cmd_ctx->lsm->session_uuid)) {
296 uuid_copy(cmd_ctx->llm->session_uuid, cmd_ctx->lsm->session_uuid);
297 }
298
299 cmd_ctx->llm->trace_name_offset = trace_name_size;
300 cmd_ctx->llm->data_size = size;
301 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
302
303 /* Copy trace name to the llm structure. Begining of the payload. */
304 memcpy(cmd_ctx->llm->payload, cmd_ctx->lsm->trace_name, trace_name_size);
305
306 return buf_size;
307
308 error:
309 return ret;
310 }
311
312 /*
313 * thread_manage_kconsumerd
314 *
315 * This thread manage the kconsumerd error sent
316 * back to the session daemon.
317 */
318 static void *thread_manage_kconsumerd(void *data)
319 {
320 int sock, ret;
321 enum lttcomm_return_code code;
322
323 DBG("[thread] Manage kconsumerd started");
324
325 ret = lttcomm_listen_unix_sock(kconsumerd_err_sock);
326 if (ret < 0) {
327 goto error;
328 }
329
330 sock = lttcomm_accept_unix_sock(kconsumerd_err_sock);
331 if (sock < 0) {
332 goto error;
333 }
334
335 /* Getting status code from kconsumerd */
336 ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
337 if (ret <= 0) {
338 goto error;
339 }
340
341 if (code == KCONSUMERD_COMMAND_SOCK_READY) {
342 kconsumerd_cmd_sock = lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path);
343 if (kconsumerd_cmd_sock < 0) {
344 sem_post(&kconsumerd_sem);
345 perror("kconsumerd connect");
346 goto error;
347 }
348 /* Signal condition to tell that the kconsumerd is ready */
349 sem_post(&kconsumerd_sem);
350 DBG("Kconsumerd command socket ready");
351 } else {
352 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
353 lttcomm_get_readable_code(-code));
354 goto error;
355 }
356
357 /* Wait for any kconsumerd error */
358 ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
359 if (ret <= 0) {
360 ERR("Kconsumerd closed the command socket");
361 goto error;
362 }
363
364 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code));
365
366 error:
367 kconsumerd_pid = 0;
368 DBG("Kconsumerd thread dying");
369 return NULL;
370 }
371
372 /*
373 * thread_manage_apps
374 *
375 * This thread manage the application socket communication
376 */
377 static void *thread_manage_apps(void *data)
378 {
379 int sock, ret;
380
381 /* TODO: Something more elegant is needed but fine for now */
382 /* FIXME: change all types to either uint8_t, uint32_t, uint64_t
383 * for 32-bit vs 64-bit compat processes. */
384 /* replicate in ust with version number */
385 struct {
386 int reg; /* 1:register, 0:unregister */
387 pid_t pid;
388 uid_t uid;
389 } reg_msg;
390
391 DBG("[thread] Manage apps started");
392
393 ret = lttcomm_listen_unix_sock(apps_sock);
394 if (ret < 0) {
395 goto error;
396 }
397
398 /* Notify all applications to register */
399 notify_apps(default_global_apps_pipe);
400
401 while (1) {
402 DBG("Accepting application registration");
403 /* Blocking call, waiting for transmission */
404 sock = lttcomm_accept_unix_sock(apps_sock);
405 if (sock < 0) {
406 goto error;
407 }
408
409 /* Basic recv here to handle the very simple data
410 * that the libust send to register (reg_msg).
411 */
412 ret = recv(sock, &reg_msg, sizeof(reg_msg), 0);
413 if (ret < 0) {
414 perror("recv");
415 continue;
416 }
417
418 /* Add application to the global traceable list */
419 if (reg_msg.reg == 1) {
420 /* Registering */
421 ret = register_traceable_app(reg_msg.pid, reg_msg.uid);
422 if (ret < 0) {
423 /* register_traceable_app only return an error with
424 * ENOMEM. At this point, we better stop everything.
425 */
426 goto error;
427 }
428 } else {
429 /* Unregistering */
430 unregister_traceable_app(reg_msg.pid);
431 }
432 }
433
434 error:
435
436 return NULL;
437 }
438
439 /*
440 * spawn_kconsumerd_thread
441 *
442 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
443 * exec or it will fails.
444 */
445 static int spawn_kconsumerd_thread(void)
446 {
447 int ret;
448
449 /* Setup semaphore */
450 sem_init(&kconsumerd_sem, 0, 0);
451
452 ret = pthread_create(&kconsumerd_thread, NULL, thread_manage_kconsumerd, (void *) NULL);
453 if (ret != 0) {
454 perror("pthread_create kconsumerd");
455 goto error;
456 }
457
458 /* Wait for the kconsumerd thread to be ready */
459 sem_wait(&kconsumerd_sem);
460
461 if (kconsumerd_pid == 0) {
462 ERR("Kconsumerd did not start");
463 goto error;
464 }
465
466 return 0;
467
468 error:
469 ret = LTTCOMM_KERN_CONSUMER_FAIL;
470 return ret;
471 }
472
473 /*
474 * spawn_kconsumerd
475 *
476 * Fork and exec a kernel consumer daemon (kconsumerd).
477 *
478 * NOTE: It is very important to fork a kconsumerd BEFORE opening any kernel
479 * file descriptor using the libkernelctl or kernel-ctl functions. So, a
480 * kernel consumer MUST only be spawned before creating a kernel session.
481 *
482 * Return pid if successful else -1.
483 */
484 static pid_t spawn_kconsumerd(void)
485 {
486 int ret;
487 pid_t pid;
488
489 DBG("Spawning kconsumerd");
490
491 pid = fork();
492 if (pid == 0) {
493 /*
494 * Exec kconsumerd.
495 */
496 execlp("kconsumerd", "kconsumerd", "--quiet", NULL);
497 if (errno != 0) {
498 perror("kernel start consumer exec");
499 }
500 exit(EXIT_FAILURE);
501 } else if (pid > 0) {
502 ret = pid;
503 goto error;
504 } else {
505 perror("kernel start consumer fork");
506 ret = -errno;
507 goto error;
508 }
509
510 error:
511 return ret;
512 }
513
514 /*
515 * start_kconsumerd
516 *
517 * Spawn the kconsumerd daemon and session daemon thread.
518 */
519 static int start_kconsumerd(void)
520 {
521 int ret;
522
523 pthread_mutex_lock(&kconsumerd_pid_mutex);
524 if (kconsumerd_pid != 0) {
525 goto end;
526 }
527
528 ret = spawn_kconsumerd();
529 if (ret < 0) {
530 ERR("Spawning kconsumerd failed");
531 ret = LTTCOMM_KERN_CONSUMER_FAIL;
532 pthread_mutex_unlock(&kconsumerd_pid_mutex);
533 goto error;
534 }
535
536 /* Setting up the global kconsumerd_pid */
537 kconsumerd_pid = ret;
538 pthread_mutex_unlock(&kconsumerd_pid_mutex);
539
540 DBG("Kconsumerd pid %d", ret);
541
542 DBG("Spawning kconsumerd thread");
543 ret = spawn_kconsumerd_thread();
544 if (ret < 0) {
545 ERR("Fatal error spawning kconsumerd thread");
546 goto error;
547 }
548
549 end:
550 pthread_mutex_unlock(&kconsumerd_pid_mutex);
551 return 0;
552
553 error:
554 return ret;
555 }
556
557 /*
558 * send_kconsumerd_fds
559 *
560 * Send all stream fds of the kernel session to the consumer.
561 */
562 static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session)
563 {
564 int ret;
565 size_t nb_fd;
566 struct ltt_kernel_stream *stream;
567 struct ltt_kernel_channel *chan;
568 struct lttcomm_kconsumerd_header lkh;
569 struct lttcomm_kconsumerd_msg lkm;
570
571 nb_fd = session->stream_count_global;
572
573 /* Setup header */
574 lkh.payload_size = (nb_fd + 1) * sizeof(struct lttcomm_kconsumerd_msg);
575 lkh.cmd_type = ADD_STREAM;
576
577 DBG("Sending kconsumerd header");
578
579 ret = lttcomm_send_unix_sock(sock, &lkh, sizeof(struct lttcomm_kconsumerd_header));
580 if (ret < 0) {
581 perror("send kconsumerd header");
582 goto error;
583 }
584
585 DBG("Sending metadata stream fd");
586
587 /* Send metadata stream fd first */
588 lkm.fd = session->metadata_stream_fd;
589 lkm.state = ACTIVE_FD;
590 lkm.max_sb_size = session->metadata->conf->subbuf_size;
591 strncpy(lkm.path_name, session->metadata->pathname, PATH_MAX);
592
593 ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
594 if (ret < 0) {
595 perror("send kconsumerd fd");
596 goto error;
597 }
598
599 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
600 cds_list_for_each_entry(stream, &chan->stream_list.head, list) {
601 lkm.fd = stream->fd;
602 lkm.state = stream->state;
603 lkm.max_sb_size = chan->channel->subbuf_size;
604 strncpy(lkm.path_name, stream->pathname, PATH_MAX);
605
606 DBG("Sending fd %d to kconsumerd", lkm.fd);
607
608 ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
609 if (ret < 0) {
610 perror("send kconsumerd fd");
611 goto error;
612 }
613 }
614 }
615
616 DBG("Kconsumerd fds sent");
617
618 return 0;
619
620 error:
621 return ret;
622 }
623
624 /*
625 * create_trace_dir
626 *
627 * Create the trace output directory.
628 */
629 static int create_trace_dir(struct ltt_kernel_session *session)
630 {
631 int ret;
632 struct ltt_kernel_channel *chan;
633
634 /* Create all channel directories */
635 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
636 DBG("Creating trace directory at %s", chan->pathname);
637 ret = mkdir(chan->pathname, S_IRWXU | S_IRWXG );
638 if (ret < 0) {
639 perror("mkdir trace path");
640 ret = -errno;
641 goto error;
642 }
643 }
644
645 return 0;
646
647 error:
648 return ret;
649 }
650
651 /*
652 * process_client_msg
653 *
654 * Process the command requested by the lttng client within the command
655 * context structure. This function make sure that the return structure (llm)
656 * is set and ready for transmission before returning.
657 *
658 * Return any error encountered or 0 for success.
659 */
660 static int process_client_msg(struct command_ctx *cmd_ctx)
661 {
662 int ret;
663
664 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
665
666 /* Check command that needs a session */
667 switch (cmd_ctx->lsm->cmd_type) {
668 case LTTNG_CREATE_SESSION:
669 case LTTNG_LIST_SESSIONS:
670 case KERNEL_LIST_EVENTS:
671 case UST_LIST_APPS:
672 break;
673 default:
674 cmd_ctx->session = find_session_by_uuid(cmd_ctx->lsm->session_uuid);
675 if (cmd_ctx->session == NULL) {
676 ret = LTTCOMM_SELECT_SESS;
677 goto error;
678 }
679 break;
680 }
681
682 /* Check command for kernel tracing */
683 switch (cmd_ctx->lsm->cmd_type) {
684 case KERNEL_CREATE_SESSION:
685 case KERNEL_CREATE_CHANNEL:
686 case KERNEL_CREATE_STREAM:
687 case KERNEL_DISABLE_EVENT:
688 case KERNEL_ENABLE_EVENT:
689 case KERNEL_LIST_EVENTS:
690 case KERNEL_OPEN_METADATA:
691 case KERNEL_START_TRACE:
692 case KERNEL_STOP_TRACE:
693 /* TODO: reconnect to kernel tracer to check if
694 * it's loadded */
695 if (kernel_tracer_fd == 0) {
696 ret = LTTCOMM_KERN_NA;
697 goto error;
698 }
699 break;
700 }
701
702 /* Connect to ust apps if available pid */
703 if (cmd_ctx->lsm->pid > 0) {
704 /* Connect to app using ustctl API */
705 cmd_ctx->ust_sock = ust_connect_app(cmd_ctx->lsm->pid);
706 if (cmd_ctx->ust_sock < 0) {
707 ret = LTTCOMM_NO_TRACEABLE;
708 goto error;
709 }
710 }
711
712 /* Process by command type */
713 switch (cmd_ctx->lsm->cmd_type) {
714 case KERNEL_CREATE_SESSION:
715 {
716 ret = setup_lttng_msg(cmd_ctx, 0);
717 if (ret < 0) {
718 goto setup_error;
719 }
720
721 ret = start_kconsumerd();
722 if (ret < 0) {
723 goto error;
724 }
725
726 DBG("Creating kernel session");
727
728 ret = kernel_create_session(cmd_ctx->session, kernel_tracer_fd);
729 if (ret < 0) {
730 ret = LTTCOMM_KERN_SESS_FAIL;
731 goto error;
732 }
733
734 ret = LTTCOMM_OK;
735 break;
736 }
737 case KERNEL_CREATE_CHANNEL:
738 {
739 ret = setup_lttng_msg(cmd_ctx, 0);
740 if (ret < 0) {
741 goto setup_error;
742 }
743
744 DBG("Creating kernel channel");
745
746 ret = kernel_create_channel(cmd_ctx->session->kernel_session);
747
748 if (ret < 0) {
749 ret = LTTCOMM_KERN_CHAN_FAIL;
750 goto error;
751 }
752
753 ret = LTTCOMM_OK;
754 break;
755 }
756 case KERNEL_ENABLE_EVENT:
757 {
758 /* Setup lttng message with no payload */
759 ret = setup_lttng_msg(cmd_ctx, 0);
760 if (ret < 0) {
761 goto setup_error;
762 }
763
764 DBG("Enabling kernel event %s", cmd_ctx->lsm->u.event.event_name);
765
766 ret = kernel_enable_event(cmd_ctx->session->kernel_session, cmd_ctx->lsm->u.event.event_name);
767 if (ret < 0) {
768 ret = LTTCOMM_KERN_ENABLE_FAIL;
769 goto error;
770 }
771
772 ret = LTTCOMM_OK;
773 break;
774 }
775 case KERNEL_ENABLE_ALL_EVENT:
776 {
777 int pos, size;
778 char *event_list, *event, *ptr;
779
780 /* Setup lttng message with no payload */
781 ret = setup_lttng_msg(cmd_ctx, 0);
782 if (ret < 0) {
783 goto setup_error;
784 }
785
786 DBG("Enabling all kernel event");
787
788 size = kernel_list_events(kernel_tracer_fd, &event_list);
789 if (size < 0) {
790 ret = LTTCOMM_KERN_LIST_FAIL;
791 goto error;
792 }
793
794 ptr = event_list;
795 while ((size = sscanf(ptr, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) {
796 /* Enable each single event */
797 ret = kernel_enable_event(cmd_ctx->session->kernel_session, event);
798 if (ret < 0) {
799 ret = LTTCOMM_KERN_ENABLE_FAIL;
800 goto error;
801 }
802 /* Move pointer to the next line */
803 ptr += pos + 1;
804 free(event);
805 }
806
807 free(event_list);
808
809 ret = LTTCOMM_OK;
810 break;
811 }
812 case KERNEL_LIST_EVENTS:
813 {
814 char *event_list;
815 ssize_t size;
816
817 size = kernel_list_events(kernel_tracer_fd, &event_list);
818 if (size < 0) {
819 ret = LTTCOMM_KERN_LIST_FAIL;
820 goto error;
821 }
822
823 /*
824 * Setup lttng message with payload size set to the event list size in
825 * bytes and then copy list into the llm payload.
826 */
827 ret = setup_lttng_msg(cmd_ctx, size);
828 if (ret < 0) {
829 goto setup_error;
830 }
831
832 /* Copy event list into message payload */
833 memcpy(cmd_ctx->llm->payload, event_list, size);
834
835 free(event_list);
836
837 ret = LTTCOMM_OK;
838 break;
839 }
840 case KERNEL_OPEN_METADATA:
841 {
842 /* Setup lttng message with no payload */
843 ret = setup_lttng_msg(cmd_ctx, 0);
844 if (ret < 0) {
845 goto setup_error;
846 }
847
848 DBG("Open kernel metadata");
849
850 ret = kernel_open_metadata(cmd_ctx->session->kernel_session);
851 if (ret < 0) {
852 ret = LTTCOMM_KERN_META_FAIL;
853 goto error;
854 }
855
856 ret = LTTCOMM_OK;
857 break;
858 }
859 case KERNEL_CREATE_STREAM:
860 {
861 struct ltt_kernel_channel *chan;
862 /* Setup lttng message with no payload */
863 ret = setup_lttng_msg(cmd_ctx, 0);
864 if (ret < 0) {
865 goto setup_error;
866 }
867
868 DBG("Creating kernel stream");
869
870 ret = kernel_create_metadata_stream(cmd_ctx->session->kernel_session);
871 if (ret < 0) {
872 ERR("Kernel create metadata stream failed");
873 ret = LTTCOMM_KERN_STREAM_FAIL;
874 goto error;
875 }
876
877 /* For each channel */
878 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
879 ret = kernel_create_channel_stream(chan);
880 if (ret < 0) {
881 ERR("Kernel create channel stream failed");
882 ret = LTTCOMM_KERN_STREAM_FAIL;
883 goto error;
884 }
885 /* Update the stream global counter */
886 cmd_ctx->session->kernel_session->stream_count_global += ret;
887 }
888
889 ret = LTTCOMM_OK;
890 break;
891 }
892 case KERNEL_START_TRACE:
893 {
894 /* Setup lttng message with no payload */
895 ret = setup_lttng_msg(cmd_ctx, 0);
896 if (ret < 0) {
897 goto setup_error;
898 }
899
900 DBG("Start kernel tracing");
901
902 ret = create_trace_dir(cmd_ctx->session->kernel_session);
903 if (ret < 0) {
904 if (ret == -EEXIST) {
905 ret = LTTCOMM_KERN_DIR_EXIST;
906 } else {
907 ret = LTTCOMM_KERN_DIR_FAIL;
908 goto error;
909 }
910 }
911
912 ret = kernel_start_session(cmd_ctx->session->kernel_session);
913 if (ret < 0) {
914 ERR("Kernel start session failed");
915 ret = LTTCOMM_KERN_START_FAIL;
916 goto error;
917 }
918
919 ret = send_kconsumerd_fds(kconsumerd_cmd_sock, cmd_ctx->session->kernel_session);
920 if (ret < 0) {
921 ERR("Send kconsumerd fds failed");
922 ret = LTTCOMM_KERN_CONSUMER_FAIL;
923 goto error;
924 }
925
926 ret = LTTCOMM_OK;
927 break;
928 }
929 case KERNEL_STOP_TRACE:
930 {
931 /* Setup lttng message with no payload */
932 ret = setup_lttng_msg(cmd_ctx, 0);
933 if (ret < 0) {
934 goto setup_error;
935 }
936
937 if (cmd_ctx->session->kernel_session == NULL) {
938 ret = LTTCOMM_KERN_NO_SESSION;
939 goto error;
940 }
941
942 DBG("Stop kernel tracing");
943
944 ret = kernel_stop_session(cmd_ctx->session->kernel_session);
945 if (ret < 0) {
946 ERR("Kernel stop session failed");
947 ret = LTTCOMM_KERN_STOP_FAIL;
948 goto error;
949 }
950
951 /* Clean kernel session teardown */
952 teardown_kernel_session(cmd_ctx->session);
953
954 ret = LTTCOMM_OK;
955 break;
956 }
957 case LTTNG_CREATE_SESSION:
958 {
959 /* Setup lttng message with no payload */
960 ret = setup_lttng_msg(cmd_ctx, 0);
961 if (ret < 0) {
962 goto setup_error;
963 }
964
965 ret = create_session(cmd_ctx->lsm->session_name, &cmd_ctx->llm->session_uuid);
966 if (ret < 0) {
967 if (ret == -1) {
968 ret = LTTCOMM_EXIST_SESS;
969 } else {
970 ret = LTTCOMM_FATAL;
971 }
972 goto error;
973 }
974
975 ret = LTTCOMM_OK;
976 break;
977 }
978 case LTTNG_DESTROY_SESSION:
979 {
980 /* Setup lttng message with no payload */
981 ret = setup_lttng_msg(cmd_ctx, 0);
982 if (ret < 0) {
983 goto setup_error;
984 }
985
986 ret = destroy_session(&cmd_ctx->lsm->session_uuid);
987 if (ret < 0) {
988 ret = LTTCOMM_NO_SESS;
989 goto error;
990 }
991
992 ret = LTTCOMM_OK;
993 break;
994 }
995 case LTTNG_LIST_TRACES:
996 {
997 unsigned int trace_count;
998
999 trace_count = get_trace_count_per_session(cmd_ctx->session);
1000 if (trace_count == 0) {
1001 ret = LTTCOMM_NO_TRACE;
1002 goto error;
1003 }
1004
1005 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count);
1006 if (ret < 0) {
1007 goto setup_error;
1008 }
1009
1010 get_traces_per_session(cmd_ctx->session,
1011 (struct lttng_trace *)(cmd_ctx->llm->payload));
1012
1013 ret = LTTCOMM_OK;
1014 break;
1015 }
1016 case UST_CREATE_TRACE:
1017 {
1018 /* Setup lttng message with no payload */
1019 ret = setup_lttng_msg(cmd_ctx, 0);
1020 if (ret < 0) {
1021 goto setup_error;
1022 }
1023
1024 ret = ust_create_trace(cmd_ctx);
1025 if (ret < 0) {
1026 goto setup_error;
1027 }
1028 break;
1029 }
1030 case UST_LIST_APPS:
1031 {
1032 unsigned int app_count;
1033
1034 app_count = get_app_count();
1035 DBG("Traceable application count : %d", app_count);
1036 if (app_count == 0) {
1037 ret = LTTCOMM_NO_APPS;
1038 goto error;
1039 }
1040
1041 ret = setup_lttng_msg(cmd_ctx, sizeof(pid_t) * app_count);
1042 if (ret < 0) {
1043 goto setup_error;
1044 }
1045
1046 get_app_list_pids((pid_t *)(cmd_ctx->llm->payload));
1047
1048 ret = LTTCOMM_OK;
1049 break;
1050 }
1051 case UST_START_TRACE:
1052 {
1053 /* Setup lttng message with no payload */
1054 ret = setup_lttng_msg(cmd_ctx, 0);
1055 if (ret < 0) {
1056 goto setup_error;
1057 }
1058
1059 ret = ust_start_trace(cmd_ctx);
1060 if (ret < 0) {
1061 goto setup_error;
1062 }
1063 break;
1064 }
1065 case UST_STOP_TRACE:
1066 {
1067 /* Setup lttng message with no payload */
1068 ret = setup_lttng_msg(cmd_ctx, 0);
1069 if (ret < 0) {
1070 goto setup_error;
1071 }
1072
1073 ret = ust_stop_trace(cmd_ctx);
1074 if (ret < 0) {
1075 goto setup_error;
1076 }
1077 break;
1078 }
1079 case LTTNG_LIST_SESSIONS:
1080 {
1081 unsigned int session_count;
1082
1083 session_count = get_session_count();
1084 if (session_count == 0) {
1085 ret = LTTCOMM_NO_SESS;
1086 goto error;
1087 }
1088
1089 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count);
1090 if (ret < 0) {
1091 goto setup_error;
1092 }
1093
1094 get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload));
1095
1096 ret = LTTCOMM_OK;
1097 break;
1098 }
1099 default:
1100 /* Undefined command */
1101 ret = setup_lttng_msg(cmd_ctx, 0);
1102 if (ret < 0) {
1103 goto setup_error;
1104 }
1105
1106 ret = LTTCOMM_UND;
1107 break;
1108 }
1109
1110 /* Set return code */
1111 cmd_ctx->llm->ret_code = ret;
1112
1113 return ret;
1114
1115 error:
1116 if (cmd_ctx->llm == NULL) {
1117 DBG("Missing llm structure. Allocating one.");
1118 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
1119 goto setup_error;
1120 }
1121 }
1122 /* Notify client of error */
1123 cmd_ctx->llm->ret_code = ret;
1124
1125 setup_error:
1126 return ret;
1127 }
1128
1129 /*
1130 * thread_manage_clients
1131 *
1132 * This thread manage all clients request using the unix
1133 * client socket for communication.
1134 */
1135 static void *thread_manage_clients(void *data)
1136 {
1137 int sock, ret;
1138 struct command_ctx *cmd_ctx;
1139
1140 DBG("[thread] Manage client started");
1141
1142 ret = lttcomm_listen_unix_sock(client_sock);
1143 if (ret < 0) {
1144 goto error;
1145 }
1146
1147 /* Notify parent pid that we are ready
1148 * to accept command for client side.
1149 */
1150 if (opt_sig_parent) {
1151 kill(ppid, SIGCHLD);
1152 }
1153
1154 while (1) {
1155 /* Blocking call, waiting for transmission */
1156 DBG("Accepting client command ...");
1157 sock = lttcomm_accept_unix_sock(client_sock);
1158 if (sock < 0) {
1159 goto error;
1160 }
1161
1162 /* Allocate context command to process the client request */
1163 cmd_ctx = malloc(sizeof(struct command_ctx));
1164
1165 /* Allocate data buffer for reception */
1166 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
1167 cmd_ctx->llm = NULL;
1168 cmd_ctx->session = NULL;
1169
1170 /*
1171 * Data is received from the lttng client. The struct
1172 * lttcomm_session_msg (lsm) contains the command and data request of
1173 * the client.
1174 */
1175 DBG("Receiving data from client ...");
1176 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
1177 if (ret <= 0) {
1178 continue;
1179 }
1180
1181 /*
1182 * This function dispatch the work to the kernel or userspace tracer
1183 * libs and fill the lttcomm_lttng_msg data structure of all the needed
1184 * informations for the client. The command context struct contains
1185 * everything this function may needs.
1186 */
1187 ret = process_client_msg(cmd_ctx);
1188 if (ret < 0) {
1189 /* TODO: Inform client somehow of the fatal error. At this point,
1190 * ret < 0 means that a malloc failed (ENOMEM). */
1191 /* Error detected but still accept command */
1192 clean_command_ctx(cmd_ctx);
1193 continue;
1194 }
1195
1196 DBG("Sending response (size: %d, retcode: %d)",
1197 cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
1198 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
1199 if (ret < 0) {
1200 ERR("Failed to send data back to client");
1201 }
1202
1203 clean_command_ctx(cmd_ctx);
1204
1205 /* End of transmission */
1206 close(sock);
1207 }
1208
1209 error:
1210 return NULL;
1211 }
1212
1213
1214 /*
1215 * usage function on stderr
1216 */
1217 static void usage(void)
1218 {
1219 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
1220 fprintf(stderr, " -h, --help Display this usage.\n");
1221 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
1222 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
1223 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
1224 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
1225 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
1226 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
1227 fprintf(stderr, " -V, --version Show version number.\n");
1228 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
1229 fprintf(stderr, " -q, --quiet No output at all.\n");
1230 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
1231 }
1232
1233 /*
1234 * daemon argument parsing
1235 */
1236 static int parse_args(int argc, char **argv)
1237 {
1238 int c;
1239
1240 static struct option long_options[] = {
1241 { "client-sock", 1, 0, 'c' },
1242 { "apps-sock", 1, 0, 'a' },
1243 { "kconsumerd-cmd-sock", 1, 0, 0 },
1244 { "kconsumerd-err-sock", 1, 0, 0 },
1245 { "daemonize", 0, 0, 'd' },
1246 { "sig-parent", 0, 0, 'S' },
1247 { "help", 0, 0, 'h' },
1248 { "group", 1, 0, 'g' },
1249 { "version", 0, 0, 'V' },
1250 { "quiet", 0, 0, 'q' },
1251 { "verbose", 0, 0, 'v' },
1252 { NULL, 0, 0, 0 }
1253 };
1254
1255 while (1) {
1256 int option_index = 0;
1257 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:E:C:", long_options, &option_index);
1258 if (c == -1) {
1259 break;
1260 }
1261
1262 switch (c) {
1263 case 0:
1264 fprintf(stderr, "option %s", long_options[option_index].name);
1265 if (optarg) {
1266 fprintf(stderr, " with arg %s\n", optarg);
1267 }
1268 break;
1269 case 'c':
1270 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
1271 break;
1272 case 'a':
1273 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
1274 break;
1275 case 'd':
1276 opt_daemon = 1;
1277 break;
1278 case 'g':
1279 opt_tracing_group = strdup(optarg);
1280 break;
1281 case 'h':
1282 usage();
1283 exit(EXIT_FAILURE);
1284 case 'V':
1285 fprintf(stdout, "%s\n", VERSION);
1286 exit(EXIT_SUCCESS);
1287 case 'S':
1288 opt_sig_parent = 1;
1289 break;
1290 case 'E':
1291 snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, "%s", optarg);
1292 break;
1293 case 'C':
1294 snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, "%s", optarg);
1295 break;
1296 case 'q':
1297 opt_quiet = 1;
1298 break;
1299 case 'v':
1300 opt_verbose = 1;
1301 break;
1302 default:
1303 /* Unknown option or other error.
1304 * Error is printed by getopt, just return */
1305 return -1;
1306 }
1307 }
1308
1309 return 0;
1310 }
1311
1312 /*
1313 * init_daemon_socket
1314 *
1315 * Creates the two needed socket by the daemon.
1316 * apps_sock - The communication socket for all UST apps.
1317 * client_sock - The communication of the cli tool (lttng).
1318 */
1319 static int init_daemon_socket()
1320 {
1321 int ret = 0;
1322 mode_t old_umask;
1323
1324 old_umask = umask(0);
1325
1326 /* Create client tool unix socket */
1327 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
1328 if (client_sock < 0) {
1329 ERR("Create unix sock failed: %s", client_unix_sock_path);
1330 ret = -1;
1331 goto end;
1332 }
1333
1334 /* File permission MUST be 660 */
1335 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1336 if (ret < 0) {
1337 ERR("Set file permissions failed: %s", client_unix_sock_path);
1338 perror("chmod");
1339 goto end;
1340 }
1341
1342 /* Create the application unix socket */
1343 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
1344 if (apps_sock < 0) {
1345 ERR("Create unix sock failed: %s", apps_unix_sock_path);
1346 ret = -1;
1347 goto end;
1348 }
1349
1350 /* File permission MUST be 666 */
1351 ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
1352 if (ret < 0) {
1353 ERR("Set file permissions failed: %s", apps_unix_sock_path);
1354 perror("chmod");
1355 goto end;
1356 }
1357
1358 end:
1359 umask(old_umask);
1360 return ret;
1361 }
1362
1363 /*
1364 * check_existing_daemon
1365 *
1366 * Check if the global socket is available.
1367 * If yes, error is returned.
1368 */
1369 static int check_existing_daemon()
1370 {
1371 int ret;
1372
1373 ret = access(client_unix_sock_path, F_OK);
1374 if (ret == 0) {
1375 ret = access(apps_unix_sock_path, F_OK);
1376 }
1377
1378 return ret;
1379 }
1380
1381 /*
1382 * get_home_dir
1383 *
1384 * Return pointer to home directory path using
1385 * the env variable HOME.
1386 *
1387 * Default : /tmp
1388 */
1389 static const char *get_home_dir(void)
1390 {
1391 const char *home_path;
1392
1393 if ((home_path = (const char *) getenv("HOME")) == NULL) {
1394 home_path = default_home_dir;
1395 }
1396
1397 return home_path;
1398 }
1399
1400 /*
1401 * set_permissions
1402 *
1403 * Set the tracing group gid onto the client socket.
1404 *
1405 * Race window between mkdir and chown is OK because we are going from
1406 * less permissive (root.root) to more permissive (root.tracing).
1407 */
1408 static int set_permissions(void)
1409 {
1410 int ret;
1411 struct group *grp;
1412
1413 /* Decide which group name to use */
1414 (opt_tracing_group != NULL) ?
1415 (grp = getgrnam(opt_tracing_group)) :
1416 (grp = getgrnam(default_tracing_group));
1417
1418 if (grp == NULL) {
1419 ERR("Missing tracing group. Aborting execution.\n");
1420 ret = -1;
1421 goto end;
1422 }
1423
1424 /* Set lttng run dir */
1425 ret = chown(LTTNG_RUNDIR, 0, grp->gr_gid);
1426 if (ret < 0) {
1427 ERR("Unable to set group on " LTTNG_RUNDIR);
1428 perror("chown");
1429 }
1430
1431 /* lttng client socket path */
1432 ret = chown(client_unix_sock_path, 0, grp->gr_gid);
1433 if (ret < 0) {
1434 ERR("Unable to set group on %s", client_unix_sock_path);
1435 perror("chown");
1436 }
1437
1438 /* kconsumerd error socket path */
1439 ret = chown(kconsumerd_err_unix_sock_path, 0, grp->gr_gid);
1440 if (ret < 0) {
1441 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path);
1442 perror("chown");
1443 }
1444
1445 DBG("All permissions are set");
1446
1447 end:
1448 return ret;
1449 }
1450
1451 /*
1452 * create_lttng_rundir
1453 *
1454 * Create the lttng run directory needed for all
1455 * global sockets and pipe.
1456 */
1457 static int create_lttng_rundir(void)
1458 {
1459 int ret;
1460
1461 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
1462 if (ret < 0) {
1463 if (errno != EEXIST) {
1464 ERR("Unable to create " LTTNG_RUNDIR);
1465 goto error;
1466 } else {
1467 ret = 0;
1468 }
1469 }
1470
1471 error:
1472 return ret;
1473 }
1474
1475 /*
1476 * init_kernel_tracer
1477 *
1478 * Setup necessary data for kernel tracer action.
1479 */
1480 static void init_kernel_tracer(void)
1481 {
1482 /* Set the global kernel tracer fd */
1483 kernel_tracer_fd = open(DEFAULT_KERNEL_TRACER_PATH, O_RDWR);
1484 if (kernel_tracer_fd < 0) {
1485 WARN("No kernel tracer available");
1486 kernel_tracer_fd = 0;
1487 }
1488
1489 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1490 }
1491
1492 /*
1493 * set_kconsumerd_sockets
1494 *
1495 * Setup sockets and directory needed by the kconsumerd
1496 * communication with the session daemon.
1497 */
1498 static int set_kconsumerd_sockets(void)
1499 {
1500 int ret;
1501
1502 if (strlen(kconsumerd_err_unix_sock_path) == 0) {
1503 snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, KCONSUMERD_ERR_SOCK_PATH);
1504 }
1505
1506 if (strlen(kconsumerd_cmd_unix_sock_path) == 0) {
1507 snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, KCONSUMERD_CMD_SOCK_PATH);
1508 }
1509
1510 ret = mkdir(KCONSUMERD_PATH, S_IRWXU | S_IRWXG);
1511 if (ret < 0) {
1512 ERR("Failed to create " KCONSUMERD_PATH);
1513 goto error;
1514 }
1515
1516 /* Create the kconsumerd error unix socket */
1517 kconsumerd_err_sock = lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path);
1518 if (kconsumerd_err_sock < 0) {
1519 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path);
1520 ret = -1;
1521 goto error;
1522 }
1523
1524 /* File permission MUST be 660 */
1525 ret = chmod(kconsumerd_err_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1526 if (ret < 0) {
1527 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path);
1528 perror("chmod");
1529 goto error;
1530 }
1531
1532 error:
1533 return ret;
1534 }
1535
1536 /*
1537 * sighandler
1538 *
1539 * Signal handler for the daemon
1540 */
1541 static void sighandler(int sig)
1542 {
1543 switch (sig) {
1544 case SIGPIPE:
1545 DBG("SIGPIPE catched");
1546 return;
1547 case SIGINT:
1548 DBG("SIGINT catched");
1549 cleanup();
1550 break;
1551 case SIGTERM:
1552 DBG("SIGTERM catched");
1553 cleanup();
1554 break;
1555 default:
1556 break;
1557 }
1558
1559 exit(EXIT_SUCCESS);
1560 }
1561
1562 /*
1563 * set_signal_handler
1564 *
1565 * Setup signal handler for :
1566 * SIGINT, SIGTERM, SIGPIPE
1567 */
1568 static int set_signal_handler(void)
1569 {
1570 int ret = 0;
1571 struct sigaction sa;
1572 sigset_t sigset;
1573
1574 if ((ret = sigemptyset(&sigset)) < 0) {
1575 perror("sigemptyset");
1576 return ret;
1577 }
1578
1579 sa.sa_handler = sighandler;
1580 sa.sa_mask = sigset;
1581 sa.sa_flags = 0;
1582 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
1583 perror("sigaction");
1584 return ret;
1585 }
1586
1587 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
1588 perror("sigaction");
1589 return ret;
1590 }
1591
1592 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
1593 perror("sigaction");
1594 return ret;
1595 }
1596
1597 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
1598
1599 return ret;
1600 }
1601
1602 /*
1603 * main
1604 */
1605 int main(int argc, char **argv)
1606 {
1607 int ret = 0;
1608 void *status;
1609
1610 /* Parse arguments */
1611 progname = argv[0];
1612 if ((ret = parse_args(argc, argv) < 0)) {
1613 goto error;
1614 }
1615
1616 /* Daemonize */
1617 if (opt_daemon) {
1618 ret = daemon(0, 0);
1619 if (ret < 0) {
1620 perror("daemon");
1621 goto error;
1622 }
1623 }
1624
1625 /* Check if daemon is UID = 0 */
1626 is_root = !getuid();
1627
1628 /* Set all sockets path */
1629 if (is_root) {
1630 ret = create_lttng_rundir();
1631 if (ret < 0) {
1632 goto error;
1633 }
1634
1635 if (strlen(apps_unix_sock_path) == 0) {
1636 snprintf(apps_unix_sock_path, PATH_MAX,
1637 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
1638 }
1639
1640 if (strlen(client_unix_sock_path) == 0) {
1641 snprintf(client_unix_sock_path, PATH_MAX,
1642 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
1643 }
1644
1645 ret = set_kconsumerd_sockets();
1646 if (ret < 0) {
1647 goto error;
1648 }
1649
1650 /* Setup kernel tracer */
1651 init_kernel_tracer();
1652 } else {
1653 if (strlen(apps_unix_sock_path) == 0) {
1654 snprintf(apps_unix_sock_path, PATH_MAX,
1655 DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir());
1656 }
1657
1658 /* Set the cli tool unix socket path */
1659 if (strlen(client_unix_sock_path) == 0) {
1660 snprintf(client_unix_sock_path, PATH_MAX,
1661 DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir());
1662 }
1663 }
1664
1665 DBG("Client socket path %s", client_unix_sock_path);
1666 DBG("Application socket path %s", apps_unix_sock_path);
1667
1668 /* See if daemon already exist. If any of the two
1669 * socket needed by the daemon are present, this test fails
1670 */
1671 if ((ret = check_existing_daemon()) == 0) {
1672 ERR("Already running daemon.\n");
1673 /* We do not goto error because we must not
1674 * cleanup() because a daemon is already running.
1675 */
1676 exit(EXIT_FAILURE);
1677 }
1678
1679 if (set_signal_handler() < 0) {
1680 goto error;
1681 }
1682
1683 /* Setup the needed unix socket */
1684 if (init_daemon_socket() < 0) {
1685 goto error;
1686 }
1687
1688 /* Set credentials to socket */
1689 if (is_root && (set_permissions() < 0)) {
1690 goto error;
1691 }
1692
1693 /* Get parent pid if -S, --sig-parent is specified. */
1694 if (opt_sig_parent) {
1695 ppid = getppid();
1696 }
1697
1698 while (1) {
1699 /* Create thread to manage the client socket */
1700 ret = pthread_create(&client_thread, NULL, thread_manage_clients, (void *) NULL);
1701 if (ret != 0) {
1702 perror("pthread_create");
1703 goto error;
1704 }
1705
1706 /* Create thread to manage application socket */
1707 ret = pthread_create(&apps_thread, NULL, thread_manage_apps, (void *) NULL);
1708 if (ret != 0) {
1709 perror("pthread_create");
1710 goto error;
1711 }
1712
1713 ret = pthread_join(client_thread, &status);
1714 if (ret != 0) {
1715 perror("pthread_join");
1716 goto error;
1717 }
1718 }
1719
1720 cleanup();
1721 exit(EXIT_SUCCESS);
1722
1723 error:
1724 cleanup();
1725 exit(EXIT_FAILURE);
1726 }
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