Improve trace output path and config path
[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 <sys/time.h>
36 #include <sys/resource.h>
37 #include <unistd.h>
38
39 #include <urcu/list.h> /* URCU list library (-lurcu) */
40 #include <lttng/lttng.h>
41
42 #include "liblttsessiondcomm.h"
43 #include "ltt-sessiond.h"
44 #include "lttngerr.h"
45 #include "kernel-ctl.h"
46 #include "ust-ctl.h"
47 #include "session.h"
48 #include "traceable-app.h"
49 #include "lttng-kconsumerd.h"
50 #include "libustctl.h"
51 #include "utils.h"
52
53 /*
54 * TODO:
55 * teardown: signal SIGTERM handler -> write into pipe. Threads waits
56 * with epoll on pipe and on other pipes/sockets for commands. Main
57 * simply waits on pthread join.
58 */
59
60 /* Const values */
61 const char default_home_dir[] = DEFAULT_HOME_DIR;
62 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
63 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
64 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
65
66 /* Variables */
67 int opt_verbose; /* Not static for lttngerr.h */
68 int opt_quiet; /* Not static for lttngerr.h */
69 const char *progname;
70 const char *opt_tracing_group;
71 static int opt_sig_parent;
72 static int opt_daemon;
73 static int is_root; /* Set to 1 if the daemon is running as root */
74 static pid_t ppid; /* Parent PID for --sig-parent option */
75 static pid_t kconsumerd_pid;
76
77 static char apps_unix_sock_path[PATH_MAX]; /* Global application Unix socket path */
78 static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */
79 static char kconsumerd_err_unix_sock_path[PATH_MAX]; /* kconsumerd error Unix socket path */
80 static char kconsumerd_cmd_unix_sock_path[PATH_MAX]; /* kconsumerd command Unix socket path */
81
82 /* Sockets and FDs */
83 static int client_sock;
84 static int apps_sock;
85 static int kconsumerd_err_sock;
86 static int kconsumerd_cmd_sock;
87 static int kernel_tracer_fd;
88
89 /* Pthread, Mutexes and Semaphores */
90 static pthread_t kconsumerd_thread;
91 static pthread_t apps_thread;
92 static pthread_t client_thread;
93 static sem_t kconsumerd_sem;
94
95 static pthread_mutex_t kconsumerd_pid_mutex; /* Mutex to control kconsumerd pid assignation */
96
97 /*
98 * teardown_kernel_session
99 *
100 * Complete teardown of a kernel session. This free all data structure
101 * related to a kernel session and update counter.
102 */
103 static void teardown_kernel_session(struct ltt_session *session)
104 {
105 if (session->kernel_session != NULL) {
106 DBG("Tearing down kernel session");
107 trace_destroy_kernel_session(session->kernel_session);
108 /* Extra precaution */
109 session->kernel_session = NULL;
110 /* Decrement session count */
111 session->kern_session_count--;
112 }
113 }
114
115 /*
116 * cleanup
117 *
118 * Cleanup the daemon on exit
119 */
120 static void cleanup()
121 {
122 int ret;
123 char *cmd;
124 struct ltt_session *sess;
125
126 DBG("Cleaning up");
127
128 /* <fun> */
129 MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
130 MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0);
131 /* </fun> */
132
133 /* Stopping all threads */
134 DBG("Terminating all threads");
135 pthread_cancel(client_thread);
136 pthread_cancel(apps_thread);
137 if (kconsumerd_pid != 0) {
138 pthread_cancel(kconsumerd_thread);
139 }
140
141 DBG("Unlinking all unix socket");
142 unlink(client_unix_sock_path);
143 unlink(apps_unix_sock_path);
144 unlink(kconsumerd_err_unix_sock_path);
145
146 DBG("Removing %s directory", LTTNG_RUNDIR);
147 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
148 if (ret < 0) {
149 ERR("asprintf failed. Something is really wrong!");
150 }
151
152 /* Remove lttng run directory */
153 ret = system(cmd);
154 if (ret < 0) {
155 ERR("Unable to clean " LTTNG_RUNDIR);
156 }
157
158 DBG("Cleaning up all session");
159 /* Cleanup ALL session */
160 cds_list_for_each_entry(sess, &ltt_session_list.head, list) {
161 teardown_kernel_session(sess);
162 // TODO complete session cleanup (including UST)
163 }
164
165 DBG("Closing kernel fd");
166 close(kernel_tracer_fd);
167 }
168
169 /*
170 * send_unix_sock
171 *
172 * Send data on a unix socket using the liblttsessiondcomm API.
173 *
174 * Return lttcomm error code.
175 */
176 static int send_unix_sock(int sock, void *buf, size_t len)
177 {
178 /* Check valid length */
179 if (len <= 0) {
180 return -1;
181 }
182
183 return lttcomm_send_unix_sock(sock, buf, len);
184 }
185
186 /*
187 * clean_command_ctx
188 *
189 * Free memory of a command context structure.
190 */
191 static void clean_command_ctx(struct command_ctx *cmd_ctx)
192 {
193 DBG("Clean command context structure %p", cmd_ctx);
194 if (cmd_ctx) {
195 if (cmd_ctx->llm) {
196 free(cmd_ctx->llm);
197 }
198 if (cmd_ctx->lsm) {
199 free(cmd_ctx->lsm);
200 }
201 free(cmd_ctx);
202 cmd_ctx = NULL;
203 }
204 }
205
206 /*
207 * send_kconsumerd_fds
208 *
209 * Send all stream fds of the kernel session to the consumer.
210 */
211 static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session)
212 {
213 int ret;
214 size_t nb_fd;
215 struct ltt_kernel_stream *stream;
216 struct ltt_kernel_channel *chan;
217 struct lttcomm_kconsumerd_header lkh;
218 struct lttcomm_kconsumerd_msg lkm;
219
220 nb_fd = session->stream_count_global;
221
222 /* Setup header */
223 lkh.payload_size = (nb_fd + 1) * sizeof(struct lttcomm_kconsumerd_msg);
224 lkh.cmd_type = ADD_STREAM;
225
226 DBG("Sending kconsumerd header");
227
228 ret = lttcomm_send_unix_sock(sock, &lkh, sizeof(struct lttcomm_kconsumerd_header));
229 if (ret < 0) {
230 perror("send kconsumerd header");
231 goto error;
232 }
233
234 DBG("Sending metadata stream fd");
235
236 /* Send metadata stream fd first */
237 lkm.fd = session->metadata_stream_fd;
238 lkm.state = ACTIVE_FD;
239 lkm.max_sb_size = session->metadata->conf->attr.subbuf_size;
240 strncpy(lkm.path_name, session->metadata->pathname, PATH_MAX);
241
242 ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
243 if (ret < 0) {
244 perror("send kconsumerd fd");
245 goto error;
246 }
247
248 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
249 cds_list_for_each_entry(stream, &chan->stream_list.head, list) {
250 lkm.fd = stream->fd;
251 lkm.state = stream->state;
252 lkm.max_sb_size = chan->channel->attr.subbuf_size;
253 strncpy(lkm.path_name, stream->pathname, PATH_MAX);
254
255 DBG("Sending fd %d to kconsumerd", lkm.fd);
256
257 ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
258 if (ret < 0) {
259 perror("send kconsumerd fd");
260 goto error;
261 }
262 }
263 }
264
265 DBG("Kconsumerd fds sent");
266
267 return 0;
268
269 error:
270 return ret;
271 }
272
273 /*
274 * create_trace_dir
275 *
276 * Create the trace output directory.
277 */
278 static int create_trace_dir(struct ltt_kernel_session *session)
279 {
280 int ret;
281 struct ltt_kernel_channel *chan;
282
283 /* Create all channel directories */
284 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
285 DBG("Creating trace directory at %s", chan->pathname);
286 ret = mkdir_recursive(chan->pathname, S_IRWXU | S_IRWXG );
287 if (ret < 0) {
288 if (ret != EEXIST) {
289 ERR("Trace directory creation error");
290 goto error;
291 }
292 }
293 }
294
295 return 0;
296
297 error:
298 return ret;
299 }
300
301 /*
302 * ust_connect_app
303 *
304 * Return a socket connected to the libust communication socket
305 * of the application identified by the pid.
306 *
307 * If the pid is not found in the traceable list,
308 * return -1 to indicate error.
309 */
310 static int ust_connect_app(pid_t pid)
311 {
312 int sock;
313 struct ltt_traceable_app *lta;
314
315 DBG("Connect to application pid %d", pid);
316
317 lta = find_app_by_pid(pid);
318 if (lta == NULL) {
319 /* App not found */
320 DBG("Application pid %d not found", pid);
321 return -1;
322 }
323
324 sock = ustctl_connect_pid(lta->pid);
325 if (sock < 0) {
326 ERR("Fail connecting to the PID %d", pid);
327 }
328
329 return sock;
330 }
331
332 /*
333 * notify_apps
334 *
335 * Notify apps by writing 42 to a named pipe using name.
336 * Every applications waiting for a ltt-sessiond will be notified
337 * and re-register automatically to the session daemon.
338 *
339 * Return open or write error value.
340 */
341 static int notify_apps(const char *name)
342 {
343 int fd;
344 int ret = -1;
345
346 DBG("Notify the global application pipe");
347
348 /* Try opening the global pipe */
349 fd = open(name, O_WRONLY);
350 if (fd < 0) {
351 goto error;
352 }
353
354 /* Notify by writing on the pipe */
355 ret = write(fd, "42", 2);
356 if (ret < 0) {
357 perror("write");
358 }
359
360 error:
361 return ret;
362 }
363
364 /*
365 * setup_lttng_msg
366 *
367 * Setup the outgoing data buffer for the response (llm) by allocating the
368 * right amount of memory and copying the original information from the lsm
369 * structure.
370 *
371 * Return total size of the buffer pointed by buf.
372 */
373 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
374 {
375 int ret, buf_size;
376
377 buf_size = size;
378
379 cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
380 if (cmd_ctx->llm == NULL) {
381 perror("malloc");
382 ret = -ENOMEM;
383 goto error;
384 }
385
386 /* Copy common data */
387 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
388 cmd_ctx->llm->pid = cmd_ctx->lsm->pid;
389
390 cmd_ctx->llm->data_size = size;
391 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
392
393 return buf_size;
394
395 error:
396 return ret;
397 }
398
399 /*
400 * thread_manage_kconsumerd
401 *
402 * This thread manage the kconsumerd error sent
403 * back to the session daemon.
404 */
405 static void *thread_manage_kconsumerd(void *data)
406 {
407 int sock, ret;
408 enum lttcomm_return_code code;
409
410 DBG("[thread] Manage kconsumerd started");
411
412 ret = lttcomm_listen_unix_sock(kconsumerd_err_sock);
413 if (ret < 0) {
414 goto error;
415 }
416
417 sock = lttcomm_accept_unix_sock(kconsumerd_err_sock);
418 if (sock < 0) {
419 goto error;
420 }
421
422 /* Getting status code from kconsumerd */
423 ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
424 if (ret <= 0) {
425 goto error;
426 }
427
428 if (code == KCONSUMERD_COMMAND_SOCK_READY) {
429 kconsumerd_cmd_sock = lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path);
430 if (kconsumerd_cmd_sock < 0) {
431 sem_post(&kconsumerd_sem);
432 perror("kconsumerd connect");
433 goto error;
434 }
435 /* Signal condition to tell that the kconsumerd is ready */
436 sem_post(&kconsumerd_sem);
437 DBG("Kconsumerd command socket ready");
438 } else {
439 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
440 lttcomm_get_readable_code(-code));
441 goto error;
442 }
443
444 /* Wait for any kconsumerd error */
445 ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
446 if (ret <= 0) {
447 ERR("Kconsumerd closed the command socket");
448 goto error;
449 }
450
451 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code));
452
453 error:
454 kconsumerd_pid = 0;
455 DBG("Kconsumerd thread dying");
456 return NULL;
457 }
458
459 /*
460 * thread_manage_apps
461 *
462 * This thread manage the application socket communication
463 */
464 static void *thread_manage_apps(void *data)
465 {
466 int sock, ret;
467
468 /* TODO: Something more elegant is needed but fine for now */
469 /* FIXME: change all types to either uint8_t, uint32_t, uint64_t
470 * for 32-bit vs 64-bit compat processes. */
471 /* replicate in ust with version number */
472 struct {
473 int reg; /* 1:register, 0:unregister */
474 pid_t pid;
475 uid_t uid;
476 } reg_msg;
477
478 DBG("[thread] Manage apps started");
479
480 ret = lttcomm_listen_unix_sock(apps_sock);
481 if (ret < 0) {
482 goto error;
483 }
484
485 /* Notify all applications to register */
486 notify_apps(default_global_apps_pipe);
487
488 while (1) {
489 DBG("Accepting application registration");
490 /* Blocking call, waiting for transmission */
491 sock = lttcomm_accept_unix_sock(apps_sock);
492 if (sock < 0) {
493 goto error;
494 }
495
496 /* Basic recv here to handle the very simple data
497 * that the libust send to register (reg_msg).
498 */
499 ret = recv(sock, &reg_msg, sizeof(reg_msg), 0);
500 if (ret < 0) {
501 perror("recv");
502 continue;
503 }
504
505 /* Add application to the global traceable list */
506 if (reg_msg.reg == 1) {
507 /* Registering */
508 ret = register_traceable_app(reg_msg.pid, reg_msg.uid);
509 if (ret < 0) {
510 /* register_traceable_app only return an error with
511 * ENOMEM. At this point, we better stop everything.
512 */
513 goto error;
514 }
515 } else {
516 /* Unregistering */
517 unregister_traceable_app(reg_msg.pid);
518 }
519 }
520
521 error:
522
523 return NULL;
524 }
525
526 /*
527 * spawn_kconsumerd_thread
528 *
529 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
530 * exec or it will fails.
531 */
532 static int spawn_kconsumerd_thread(void)
533 {
534 int ret;
535
536 /* Setup semaphore */
537 sem_init(&kconsumerd_sem, 0, 0);
538
539 ret = pthread_create(&kconsumerd_thread, NULL, thread_manage_kconsumerd, (void *) NULL);
540 if (ret != 0) {
541 perror("pthread_create kconsumerd");
542 goto error;
543 }
544
545 /* Wait for the kconsumerd thread to be ready */
546 sem_wait(&kconsumerd_sem);
547
548 if (kconsumerd_pid == 0) {
549 ERR("Kconsumerd did not start");
550 goto error;
551 }
552
553 return 0;
554
555 error:
556 ret = LTTCOMM_KERN_CONSUMER_FAIL;
557 return ret;
558 }
559
560 /*
561 * spawn_kconsumerd
562 *
563 * Fork and exec a kernel consumer daemon (kconsumerd).
564 *
565 * NOTE: It is very important to fork a kconsumerd BEFORE opening any kernel
566 * file descriptor using the libkernelctl or kernel-ctl functions. So, a
567 * kernel consumer MUST only be spawned before creating a kernel session.
568 *
569 * Return pid if successful else -1.
570 */
571 static pid_t spawn_kconsumerd(void)
572 {
573 int ret;
574 pid_t pid;
575
576 DBG("Spawning kconsumerd");
577
578 pid = fork();
579 if (pid == 0) {
580 /*
581 * Exec kconsumerd.
582 */
583 execlp("kconsumerd", "kconsumerd", "--verbose", NULL);
584 if (errno != 0) {
585 perror("kernel start consumer exec");
586 }
587 exit(EXIT_FAILURE);
588 } else if (pid > 0) {
589 ret = pid;
590 goto error;
591 } else {
592 perror("kernel start consumer fork");
593 ret = -errno;
594 goto error;
595 }
596
597 error:
598 return ret;
599 }
600
601 /*
602 * start_kconsumerd
603 *
604 * Spawn the kconsumerd daemon and session daemon thread.
605 */
606 static int start_kconsumerd(void)
607 {
608 int ret;
609
610 pthread_mutex_lock(&kconsumerd_pid_mutex);
611 if (kconsumerd_pid != 0) {
612 goto end;
613 }
614
615 ret = spawn_kconsumerd();
616 if (ret < 0) {
617 ERR("Spawning kconsumerd failed");
618 ret = LTTCOMM_KERN_CONSUMER_FAIL;
619 pthread_mutex_unlock(&kconsumerd_pid_mutex);
620 goto error;
621 }
622
623 /* Setting up the global kconsumerd_pid */
624 kconsumerd_pid = ret;
625 pthread_mutex_unlock(&kconsumerd_pid_mutex);
626
627 DBG("Kconsumerd pid %d", ret);
628
629 DBG("Spawning kconsumerd thread");
630 ret = spawn_kconsumerd_thread();
631 if (ret < 0) {
632 ERR("Fatal error spawning kconsumerd thread");
633 goto error;
634 }
635
636 end:
637 pthread_mutex_unlock(&kconsumerd_pid_mutex);
638 return 0;
639
640 error:
641 return ret;
642 }
643
644 /*
645 * init_kernel_tracer
646 *
647 * Setup necessary data for kernel tracer action.
648 */
649 static void init_kernel_tracer(void)
650 {
651 /* Set the global kernel tracer fd */
652 kernel_tracer_fd = open(DEFAULT_KERNEL_TRACER_PATH, O_RDWR);
653 if (kernel_tracer_fd < 0) {
654 WARN("No kernel tracer available");
655 kernel_tracer_fd = 0;
656 }
657
658 DBG("Kernel tracer fd %d", kernel_tracer_fd);
659 }
660
661 /*
662 * start_kernel_trace
663 *
664 * Start tracing by creating trace directory and sending FDs to the kernel
665 * consumer.
666 */
667 static int start_kernel_trace(struct ltt_kernel_session *session)
668 {
669 int ret;
670
671 /* Create trace directory */
672 ret = create_trace_dir(session);
673 if (ret < 0) {
674 if (ret == -EEXIST) {
675 ret = LTTCOMM_KERN_DIR_EXIST;
676 } else {
677 ret = LTTCOMM_KERN_DIR_FAIL;
678 goto error;
679 }
680 }
681
682 if (session->kconsumer_fds_sent == 0) {
683 ret = send_kconsumerd_fds(kconsumerd_cmd_sock, session);
684 if (ret < 0) {
685 ERR("Send kconsumerd fds failed");
686 ret = LTTCOMM_KERN_CONSUMER_FAIL;
687 goto error;
688 }
689
690 session->kconsumer_fds_sent = 1;
691 }
692
693 error:
694 return ret;
695 }
696
697 /*
698 * init_default_channel
699 *
700 * Allocate a channel structure and fill it.
701 */
702 static struct lttng_channel *init_default_channel(void)
703 {
704 struct lttng_channel *chan;
705
706 chan = malloc(sizeof(struct lttng_channel));
707 if (chan == NULL) {
708 perror("init channel malloc");
709 goto error;
710 }
711
712 if (snprintf(chan->name, NAME_MAX, DEFAULT_CHANNEL_NAME) < 0) {
713 perror("snprintf defautl channel name");
714 return NULL;
715 }
716
717 chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
718 chan->attr.subbuf_size = DEFAULT_CHANNEL_SUBBUF_SIZE;
719 chan->attr.num_subbuf = DEFAULT_CHANNEL_SUBBUF_NUM;
720 chan->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
721 chan->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
722 chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
723
724 error:
725 return chan;
726 }
727
728 /*
729 * create_kernel_session
730 *
731 * Create a kernel tracer session then create the default channel.
732 */
733 static int create_kernel_session(struct ltt_session *session)
734 {
735 int ret;
736 struct lttng_channel *chan;
737
738 DBG("Creating kernel session");
739
740 ret = kernel_create_session(session, kernel_tracer_fd);
741 if (ret < 0) {
742 ret = LTTCOMM_KERN_SESS_FAIL;
743 goto error;
744 }
745
746 chan = init_default_channel();
747 if (chan == NULL) {
748 ret = LTTCOMM_FATAL;
749 goto error;
750 }
751
752 DBG("Creating default kernel channel %s", DEFAULT_CHANNEL_NAME);
753
754 ret = kernel_create_channel(session->kernel_session, chan, session->path);
755 if (ret < 0) {
756 ret = LTTCOMM_KERN_CHAN_FAIL;
757 goto error;
758 }
759
760 error:
761 return ret;
762 }
763
764 /*
765 * process_client_msg
766 *
767 * Process the command requested by the lttng client within the command
768 * context structure. This function make sure that the return structure (llm)
769 * is set and ready for transmission before returning.
770 *
771 * Return any error encountered or 0 for success.
772 */
773 static int process_client_msg(struct command_ctx *cmd_ctx)
774 {
775 int ret;
776
777 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
778
779 /* Listing commands don't need a session */
780 switch (cmd_ctx->lsm->cmd_type) {
781 case LTTNG_CREATE_SESSION:
782 case LTTNG_LIST_SESSIONS:
783 case LTTNG_LIST_EVENTS:
784 case LTTNG_KERNEL_LIST_EVENTS:
785 case LTTNG_LIST_TRACEABLE_APPS:
786 break;
787 default:
788 DBG("Getting session %s by name", cmd_ctx->lsm->session_name);
789 cmd_ctx->session = find_session_by_name(cmd_ctx->lsm->session_name);
790 if (cmd_ctx->session == NULL) {
791 /* If session name not found */
792 if (cmd_ctx->lsm->session_name != NULL) {
793 ret = LTTCOMM_SESS_NOT_FOUND;
794 } else { /* If no session name specified */
795 ret = LTTCOMM_SELECT_SESS;
796 }
797 goto error;
798 }
799 break;
800 }
801
802 /*
803 * Check kernel command for kernel session.
804 */
805 switch (cmd_ctx->lsm->cmd_type) {
806 case LTTNG_KERNEL_ADD_CONTEXT:
807 case LTTNG_KERNEL_CREATE_CHANNEL:
808 case LTTNG_KERNEL_DISABLE_ALL_EVENT:
809 case LTTNG_KERNEL_DISABLE_CHANNEL:
810 case LTTNG_KERNEL_DISABLE_EVENT:
811 case LTTNG_KERNEL_ENABLE_ALL_EVENT:
812 case LTTNG_KERNEL_ENABLE_CHANNEL:
813 case LTTNG_KERNEL_ENABLE_EVENT:
814 case LTTNG_KERNEL_LIST_EVENTS:
815 /* Kernel tracer check */
816 if (kernel_tracer_fd == 0) {
817 init_kernel_tracer();
818 if (kernel_tracer_fd == 0) {
819 ret = LTTCOMM_KERN_NA;
820 goto error;
821 }
822 }
823
824 /* Need a session for kernel command */
825 if (cmd_ctx->lsm->cmd_type != LTTNG_KERNEL_LIST_EVENTS &&
826 cmd_ctx->session->kernel_session == NULL) {
827
828 ret = create_kernel_session(cmd_ctx->session);
829 if (ret < 0) {
830 ret = LTTCOMM_KERN_SESS_FAIL;
831 goto error;
832 }
833
834 /* Start the kernel consumer daemon */
835 if (kconsumerd_pid == 0) {
836 ret = start_kconsumerd();
837 if (ret < 0) {
838 goto error;
839 }
840 }
841 }
842 }
843
844 /* Connect to ust apps if available pid */
845 if (cmd_ctx->lsm->pid > 0) {
846 /* Connect to app using ustctl API */
847 cmd_ctx->ust_sock = ust_connect_app(cmd_ctx->lsm->pid);
848 if (cmd_ctx->ust_sock < 0) {
849 ret = LTTCOMM_NO_TRACEABLE;
850 goto error;
851 }
852 }
853
854 /* Process by command type */
855 switch (cmd_ctx->lsm->cmd_type) {
856 case LTTNG_KERNEL_ADD_CONTEXT:
857 {
858 int found = 0, no_event = 0;
859 struct ltt_kernel_channel *chan;
860 struct ltt_kernel_event *event;
861
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 /* Check if event name is given */
869 if (strlen(cmd_ctx->lsm->u.context.event_name) == 0) {
870 no_event = 1;
871 }
872
873 if (strlen(cmd_ctx->lsm->u.context.channel_name) == 0) {
874 /* Go over all channels */
875 DBG("Adding context to all channels");
876 cds_list_for_each_entry(chan,
877 &cmd_ctx->session->kernel_session->channel_list.head, list) {
878 if (no_event) {
879 ret = kernel_add_channel_context(chan,
880 &cmd_ctx->lsm->u.context.ctx);
881 if (ret < 0) {
882 continue;
883 }
884 } else {
885 event = get_kernel_event_by_name(cmd_ctx->lsm->u.context.event_name, chan);
886 if (event != NULL) {
887 ret = kernel_add_event_context(event,
888 &cmd_ctx->lsm->u.context.ctx);
889 if (ret < 0) {
890 ret = LTTCOMM_KERN_CONTEXT_FAIL;
891 goto error;
892 }
893 found = 1;
894 break;
895 }
896 }
897 }
898 } else {
899 chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.context.channel_name,
900 cmd_ctx->session->kernel_session);
901 if (chan == NULL) {
902 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
903 goto error;
904 }
905
906 if (no_event) {
907 ret = kernel_add_channel_context(chan,
908 &cmd_ctx->lsm->u.context.ctx);
909 if (ret < 0) {
910 ret = LTTCOMM_KERN_CONTEXT_FAIL;
911 goto error;
912 }
913 } else {
914 event = get_kernel_event_by_name(cmd_ctx->lsm->u.context.event_name, chan);
915 if (event != NULL) {
916 ret = kernel_add_event_context(event,
917 &cmd_ctx->lsm->u.context.ctx);
918 if (ret < 0) {
919 ret = LTTCOMM_KERN_CONTEXT_FAIL;
920 goto error;
921 }
922 }
923 }
924 }
925
926 if (!found && !no_event) {
927 ret = LTTCOMM_NO_EVENT;
928 goto error;
929 }
930
931 ret = LTTCOMM_OK;
932 break;
933 }
934 case LTTNG_KERNEL_CREATE_CHANNEL:
935 {
936 /* Setup lttng message with no payload */
937 ret = setup_lttng_msg(cmd_ctx, 0);
938 if (ret < 0) {
939 goto setup_error;
940 }
941
942 /* Kernel tracer */
943 DBG("Creating kernel channel");
944
945 ret = kernel_create_channel(cmd_ctx->session->kernel_session,
946 &cmd_ctx->lsm->u.channel.chan, cmd_ctx->session->path);
947 if (ret < 0) {
948 ret = LTTCOMM_KERN_CHAN_FAIL;
949 goto error;
950 }
951
952 ret = LTTCOMM_OK;
953 break;
954 }
955 case LTTNG_KERNEL_DISABLE_CHANNEL:
956 {
957 struct ltt_kernel_channel *chan;
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 chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
966 cmd_ctx->session->kernel_session);
967 if (chan == NULL) {
968 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
969 goto error;
970 } else if (chan->enabled == 1) {
971 ret = kernel_disable_channel(chan);
972 if (ret < 0) {
973 if (ret != EEXIST) {
974 ret = LTTCOMM_KERN_CHAN_DISABLE_FAIL;
975 }
976 goto error;
977 }
978 }
979
980 kernel_wait_quiescent(kernel_tracer_fd);
981 ret = LTTCOMM_OK;
982 break;
983 }
984 case LTTNG_KERNEL_DISABLE_EVENT:
985 {
986 struct ltt_kernel_channel *chan;
987 struct ltt_kernel_event *ev;
988
989 /* Setup lttng message with no payload */
990 ret = setup_lttng_msg(cmd_ctx, 0);
991 if (ret < 0) {
992 goto setup_error;
993 }
994
995 chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
996 cmd_ctx->session->kernel_session);
997 if (chan == NULL) {
998 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
999 goto error;
1000 }
1001
1002 ev = get_kernel_event_by_name(cmd_ctx->lsm->u.disable.name, chan);
1003 if (ev != NULL) {
1004 DBG("Disabling kernel event %s for channel %s.",
1005 cmd_ctx->lsm->u.disable.name, cmd_ctx->lsm->u.disable.channel_name);
1006 ret = kernel_disable_event(ev);
1007 if (ret < 0) {
1008 ret = LTTCOMM_KERN_ENABLE_FAIL;
1009 goto error;
1010 }
1011 }
1012
1013 kernel_wait_quiescent(kernel_tracer_fd);
1014 ret = LTTCOMM_OK;
1015 break;
1016 }
1017 case LTTNG_KERNEL_DISABLE_ALL_EVENT:
1018 {
1019 struct ltt_kernel_channel *chan;
1020 struct ltt_kernel_event *ev;
1021
1022 /* Setup lttng message with no payload */
1023 ret = setup_lttng_msg(cmd_ctx, 0);
1024 if (ret < 0) {
1025 goto setup_error;
1026 }
1027
1028 DBG("Disabling all enabled kernel events");
1029
1030 chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
1031 cmd_ctx->session->kernel_session);
1032 if (chan == NULL) {
1033 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
1034 goto error;
1035 }
1036
1037 /* For each event in the kernel session */
1038 cds_list_for_each_entry(ev, &chan->events_list.head, list) {
1039 DBG("Disabling kernel event %s for channel %s.",
1040 ev->event->name, cmd_ctx->lsm->u.disable.channel_name);
1041 ret = kernel_disable_event(ev);
1042 if (ret < 0) {
1043 continue;
1044 }
1045 }
1046
1047 /* Quiescent wait after event disable */
1048 kernel_wait_quiescent(kernel_tracer_fd);
1049 ret = LTTCOMM_OK;
1050 break;
1051 }
1052 case LTTNG_KERNEL_ENABLE_CHANNEL:
1053 {
1054 struct ltt_kernel_channel *chan;
1055
1056 /* Setup lttng message with no payload */
1057 ret = setup_lttng_msg(cmd_ctx, 0);
1058 if (ret < 0) {
1059 goto setup_error;
1060 }
1061
1062 chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name,
1063 cmd_ctx->session->kernel_session);
1064 if (chan == NULL) {
1065 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
1066 goto error;
1067 } else if (chan->enabled == 0) {
1068 ret = kernel_enable_channel(chan);
1069 if (ret < 0) {
1070 if (ret != EEXIST) {
1071 ret = LTTCOMM_KERN_CHAN_ENABLE_FAIL;
1072 }
1073 goto error;
1074 }
1075 }
1076
1077 kernel_wait_quiescent(kernel_tracer_fd);
1078 ret = LTTCOMM_OK;
1079 break;
1080 }
1081 case LTTNG_KERNEL_ENABLE_EVENT:
1082 {
1083 struct ltt_kernel_channel *chan;
1084 struct ltt_kernel_event *ev;
1085
1086 /* Setup lttng message with no payload */
1087 ret = setup_lttng_msg(cmd_ctx, 0);
1088 if (ret < 0) {
1089 goto setup_error;
1090 }
1091
1092 chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name,
1093 cmd_ctx->session->kernel_session);
1094 if (chan == NULL) {
1095 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
1096 goto error;
1097 }
1098
1099 ev = get_kernel_event_by_name(cmd_ctx->lsm->u.enable.event.name, chan);
1100 if (ev == NULL) {
1101 DBG("Creating kernel event %s for channel %s.",
1102 cmd_ctx->lsm->u.enable.event.name, chan->channel->name);
1103 ret = kernel_create_event(&cmd_ctx->lsm->u.enable.event, chan);
1104 } else {
1105 DBG("Enabling kernel event %s for channel %s.",
1106 cmd_ctx->lsm->u.enable.event.name, chan->channel->name);
1107 ret = kernel_enable_event(ev);
1108 }
1109
1110 if (ret < 0) {
1111 ret = LTTCOMM_KERN_ENABLE_FAIL;
1112 goto error;
1113 }
1114
1115 kernel_wait_quiescent(kernel_tracer_fd);
1116 ret = LTTCOMM_OK;
1117 break;
1118 }
1119 case LTTNG_KERNEL_ENABLE_ALL_EVENT:
1120 {
1121 int pos, size;
1122 char *event_list, *event, *ptr;
1123 struct ltt_kernel_channel *chan;
1124 struct ltt_kernel_event *ev;
1125 struct lttng_event ev_attr;
1126
1127 /* Setup lttng message with no payload */
1128 ret = setup_lttng_msg(cmd_ctx, 0);
1129 if (ret < 0) {
1130 goto setup_error;
1131 }
1132
1133 DBG("Enabling all kernel event");
1134
1135 chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name,
1136 cmd_ctx->session->kernel_session);
1137 if (chan == NULL) {
1138 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
1139 goto error;
1140 }
1141
1142 /* For each event in the kernel session */
1143 cds_list_for_each_entry(ev, &chan->events_list.head, list) {
1144 DBG("Enabling kernel event %s for channel %s.",
1145 ev->event->name, chan->channel->name);
1146 ret = kernel_enable_event(ev);
1147 if (ret < 0) {
1148 continue;
1149 }
1150 }
1151
1152 size = kernel_list_events(kernel_tracer_fd, &event_list);
1153 if (size < 0) {
1154 ret = LTTCOMM_KERN_LIST_FAIL;
1155 goto error;
1156 }
1157
1158 ptr = event_list;
1159 while ((size = sscanf(ptr, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) {
1160 ev = get_kernel_event_by_name(event, chan);
1161 if (ev == NULL) {
1162 strncpy(ev_attr.name, event, LTTNG_SYM_NAME_LEN);
1163 /* Default event type for enable all */
1164 ev_attr.type = LTTNG_EVENT_TRACEPOINTS;
1165 /* Enable each single tracepoint event */
1166 ret = kernel_create_event(&ev_attr, chan);
1167 if (ret < 0) {
1168 /* Ignore error here and continue */
1169 }
1170 }
1171
1172 /* Move pointer to the next line */
1173 ptr += pos + 1;
1174 free(event);
1175 }
1176
1177 free(event_list);
1178
1179 /* Quiescent wait after event enable */
1180 kernel_wait_quiescent(kernel_tracer_fd);
1181 ret = LTTCOMM_OK;
1182 break;
1183 }
1184 case LTTNG_KERNEL_LIST_EVENTS:
1185 {
1186 char *event_list;
1187 ssize_t size = 0;
1188
1189 DBG("Listing kernel events");
1190
1191 size = kernel_list_events(kernel_tracer_fd, &event_list);
1192 if (size < 0) {
1193 ret = LTTCOMM_KERN_LIST_FAIL;
1194 goto error;
1195 }
1196
1197 /*
1198 * Setup lttng message with payload size set to the event list size in
1199 * bytes and then copy list into the llm payload.
1200 */
1201 ret = setup_lttng_msg(cmd_ctx, size);
1202 if (ret < 0) {
1203 goto setup_error;
1204 }
1205
1206 /* Copy event list into message payload */
1207 memcpy(cmd_ctx->llm->payload, event_list, size);
1208
1209 free(event_list);
1210
1211 ret = LTTCOMM_OK;
1212 break;
1213 }
1214 case LTTNG_START_TRACE:
1215 {
1216 struct ltt_kernel_channel *chan;
1217
1218 /* Setup lttng message with no payload */
1219 ret = setup_lttng_msg(cmd_ctx, 0);
1220 if (ret < 0) {
1221 goto setup_error;
1222 }
1223
1224 /* Kernel tracing */
1225 if (cmd_ctx->session->kernel_session != NULL) {
1226 if (cmd_ctx->session->kernel_session->metadata == NULL) {
1227 DBG("Open kernel metadata");
1228 ret = kernel_open_metadata(cmd_ctx->session->kernel_session);
1229 if (ret < 0) {
1230 ret = LTTCOMM_KERN_META_FAIL;
1231 goto error;
1232 }
1233 }
1234
1235 if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) {
1236 DBG("Opening kernel metadata stream");
1237 if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) {
1238 ret = kernel_open_metadata_stream(cmd_ctx->session->kernel_session);
1239 if (ret < 0) {
1240 ERR("Kernel create metadata stream failed");
1241 ret = LTTCOMM_KERN_STREAM_FAIL;
1242 goto error;
1243 }
1244 }
1245 }
1246
1247 /* For each channel */
1248 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
1249 if (chan->stream_count == 0) {
1250 ret = kernel_open_channel_stream(chan);
1251 if (ret < 0) {
1252 ERR("Kernel create channel stream failed");
1253 ret = LTTCOMM_KERN_STREAM_FAIL;
1254 goto error;
1255 }
1256 /* Update the stream global counter */
1257 cmd_ctx->session->kernel_session->stream_count_global += ret;
1258 }
1259 }
1260
1261 DBG("Start kernel tracing");
1262 ret = kernel_start_session(cmd_ctx->session->kernel_session);
1263 if (ret < 0) {
1264 ERR("Kernel start session failed");
1265 ret = LTTCOMM_KERN_START_FAIL;
1266 goto error;
1267 }
1268
1269 ret = start_kernel_trace(cmd_ctx->session->kernel_session);
1270 if (ret < 0) {
1271 ret = LTTCOMM_KERN_START_FAIL;
1272 goto error;
1273 }
1274
1275 /* Quiescent wait after starting trace */
1276 kernel_wait_quiescent(kernel_tracer_fd);
1277 }
1278
1279 /* TODO: Start all UST traces */
1280
1281 ret = LTTCOMM_OK;
1282 break;
1283 }
1284 case LTTNG_STOP_TRACE:
1285 {
1286 struct ltt_kernel_channel *chan;
1287 /* Setup lttng message with no payload */
1288 ret = setup_lttng_msg(cmd_ctx, 0);
1289 if (ret < 0) {
1290 goto setup_error;
1291 }
1292
1293 /* Kernel tracer */
1294 if (cmd_ctx->session->kernel_session != NULL) {
1295 DBG("Stop kernel tracing");
1296
1297 ret = kernel_metadata_flush_buffer(cmd_ctx->session->kernel_session->metadata_stream_fd);
1298 if (ret < 0) {
1299 ERR("Kernel metadata flush failed");
1300 }
1301
1302 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
1303 ret = kernel_flush_buffer(chan);
1304 if (ret < 0) {
1305 ERR("Kernel flush buffer error");
1306 }
1307 }
1308
1309 ret = kernel_stop_session(cmd_ctx->session->kernel_session);
1310 if (ret < 0) {
1311 ERR("Kernel stop session failed");
1312 ret = LTTCOMM_KERN_STOP_FAIL;
1313 goto error;
1314 }
1315
1316 /* Quiescent wait after stopping trace */
1317 kernel_wait_quiescent(kernel_tracer_fd);
1318 }
1319
1320 /* TODO : User-space tracer */
1321
1322 ret = LTTCOMM_OK;
1323 break;
1324 }
1325 case LTTNG_CREATE_SESSION:
1326 {
1327 /* Setup lttng message with no payload */
1328 ret = setup_lttng_msg(cmd_ctx, 0);
1329 if (ret < 0) {
1330 goto setup_error;
1331 }
1332
1333 ret = create_session(cmd_ctx->lsm->session_name, cmd_ctx->lsm->path);
1334 if (ret < 0) {
1335 if (ret == -EEXIST) {
1336 ret = LTTCOMM_EXIST_SESS;
1337 } else {
1338 ret = LTTCOMM_FATAL;
1339 }
1340 goto error;
1341 }
1342
1343 ret = LTTCOMM_OK;
1344 break;
1345 }
1346 case LTTNG_DESTROY_SESSION:
1347 {
1348 /* Setup lttng message with no payload */
1349 ret = setup_lttng_msg(cmd_ctx, 0);
1350 if (ret < 0) {
1351 goto setup_error;
1352 }
1353
1354 /* Clean kernel session teardown */
1355 teardown_kernel_session(cmd_ctx->session);
1356
1357 ret = destroy_session(cmd_ctx->lsm->session_name);
1358 if (ret < 0) {
1359 ret = LTTCOMM_FATAL;
1360 goto error;
1361 }
1362
1363 ret = LTTCOMM_OK;
1364 break;
1365 }
1366 /*
1367 case LTTNG_LIST_TRACES:
1368 {
1369 unsigned int trace_count;
1370
1371 trace_count = get_trace_count_per_session(cmd_ctx->session);
1372 if (trace_count == 0) {
1373 ret = LTTCOMM_NO_TRACE;
1374 goto error;
1375 }
1376
1377 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count);
1378 if (ret < 0) {
1379 goto setup_error;
1380 }
1381
1382 get_traces_per_session(cmd_ctx->session,
1383 (struct lttng_trace *)(cmd_ctx->llm->payload));
1384
1385 ret = LTTCOMM_OK;
1386 break;
1387 }
1388 */
1389 /*
1390 case UST_CREATE_TRACE:
1391 {
1392 ret = setup_lttng_msg(cmd_ctx, 0);
1393 if (ret < 0) {
1394 goto setup_error;
1395 }
1396
1397 ret = ust_create_trace(cmd_ctx);
1398 if (ret < 0) {
1399 goto error;
1400 }
1401 break;
1402 }
1403 */
1404 case LTTNG_LIST_TRACEABLE_APPS:
1405 {
1406 unsigned int app_count;
1407
1408 app_count = get_app_count();
1409 DBG("Traceable application count : %d", app_count);
1410 if (app_count == 0) {
1411 ret = LTTCOMM_NO_APPS;
1412 goto error;
1413 }
1414
1415 ret = setup_lttng_msg(cmd_ctx, sizeof(pid_t) * app_count);
1416 if (ret < 0) {
1417 goto setup_error;
1418 }
1419
1420 get_app_list_pids((pid_t *)(cmd_ctx->llm->payload));
1421
1422 ret = LTTCOMM_OK;
1423 break;
1424 }
1425 /*
1426 case UST_START_TRACE:
1427 {
1428 ret = setup_lttng_msg(cmd_ctx, 0);
1429 if (ret < 0) {
1430 goto setup_error;
1431 }
1432
1433 ret = ust_start_trace(cmd_ctx);
1434 if (ret < 0) {
1435 goto setup_error;
1436 }
1437 break;
1438 }
1439 case UST_STOP_TRACE:
1440 {
1441 ret = setup_lttng_msg(cmd_ctx, 0);
1442 if (ret < 0) {
1443 goto setup_error;
1444 }
1445
1446 ret = ust_stop_trace(cmd_ctx);
1447 if (ret < 0) {
1448 goto setup_error;
1449 }
1450 break;
1451 }
1452 */
1453 case LTTNG_LIST_SESSIONS:
1454 {
1455 unsigned int session_count;
1456
1457 session_count = get_session_count();
1458 if (session_count == 0) {
1459 ret = LTTCOMM_NO_SESSION;
1460 goto error;
1461 }
1462
1463 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count);
1464 if (ret < 0) {
1465 goto setup_error;
1466 }
1467
1468 get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload));
1469
1470 ret = LTTCOMM_OK;
1471 break;
1472 }
1473 default:
1474 /* Undefined command */
1475 ret = setup_lttng_msg(cmd_ctx, 0);
1476 if (ret < 0) {
1477 goto setup_error;
1478 }
1479
1480 ret = LTTCOMM_UND;
1481 break;
1482 }
1483
1484 /* Set return code */
1485 cmd_ctx->llm->ret_code = ret;
1486
1487 return ret;
1488
1489 error:
1490 if (cmd_ctx->llm == NULL) {
1491 DBG("Missing llm structure. Allocating one.");
1492 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
1493 goto setup_error;
1494 }
1495 }
1496 /* Notify client of error */
1497 cmd_ctx->llm->ret_code = ret;
1498
1499 setup_error:
1500 return ret;
1501 }
1502
1503 /*
1504 * thread_manage_clients
1505 *
1506 * This thread manage all clients request using the unix
1507 * client socket for communication.
1508 */
1509 static void *thread_manage_clients(void *data)
1510 {
1511 int sock, ret;
1512 struct command_ctx *cmd_ctx;
1513
1514 DBG("[thread] Manage client started");
1515
1516 ret = lttcomm_listen_unix_sock(client_sock);
1517 if (ret < 0) {
1518 goto error;
1519 }
1520
1521 /* Notify parent pid that we are ready
1522 * to accept command for client side.
1523 */
1524 if (opt_sig_parent) {
1525 kill(ppid, SIGCHLD);
1526 }
1527
1528 while (1) {
1529 /* Blocking call, waiting for transmission */
1530 DBG("Accepting client command ...");
1531 sock = lttcomm_accept_unix_sock(client_sock);
1532 if (sock < 0) {
1533 goto error;
1534 }
1535
1536 /* Allocate context command to process the client request */
1537 cmd_ctx = malloc(sizeof(struct command_ctx));
1538
1539 /* Allocate data buffer for reception */
1540 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
1541 cmd_ctx->llm = NULL;
1542 cmd_ctx->session = NULL;
1543
1544 /*
1545 * Data is received from the lttng client. The struct
1546 * lttcomm_session_msg (lsm) contains the command and data request of
1547 * the client.
1548 */
1549 DBG("Receiving data from client ...");
1550 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
1551 if (ret <= 0) {
1552 continue;
1553 }
1554
1555 // TODO: Validate cmd_ctx including sanity check for security purpose.
1556
1557 /*
1558 * This function dispatch the work to the kernel or userspace tracer
1559 * libs and fill the lttcomm_lttng_msg data structure of all the needed
1560 * informations for the client. The command context struct contains
1561 * everything this function may needs.
1562 */
1563 ret = process_client_msg(cmd_ctx);
1564 if (ret < 0) {
1565 /* TODO: Inform client somehow of the fatal error. At this point,
1566 * ret < 0 means that a malloc failed (ENOMEM). */
1567 /* Error detected but still accept command */
1568 clean_command_ctx(cmd_ctx);
1569 continue;
1570 }
1571
1572 DBG("Sending response (size: %d, retcode: %d)",
1573 cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
1574 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
1575 if (ret < 0) {
1576 ERR("Failed to send data back to client");
1577 }
1578
1579 clean_command_ctx(cmd_ctx);
1580
1581 /* End of transmission */
1582 close(sock);
1583 }
1584
1585 error:
1586 return NULL;
1587 }
1588
1589
1590 /*
1591 * usage function on stderr
1592 */
1593 static void usage(void)
1594 {
1595 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
1596 fprintf(stderr, " -h, --help Display this usage.\n");
1597 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
1598 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
1599 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
1600 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
1601 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
1602 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
1603 fprintf(stderr, " -V, --version Show version number.\n");
1604 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
1605 fprintf(stderr, " -q, --quiet No output at all.\n");
1606 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
1607 }
1608
1609 /*
1610 * daemon argument parsing
1611 */
1612 static int parse_args(int argc, char **argv)
1613 {
1614 int c;
1615
1616 static struct option long_options[] = {
1617 { "client-sock", 1, 0, 'c' },
1618 { "apps-sock", 1, 0, 'a' },
1619 { "kconsumerd-cmd-sock", 1, 0, 0 },
1620 { "kconsumerd-err-sock", 1, 0, 0 },
1621 { "daemonize", 0, 0, 'd' },
1622 { "sig-parent", 0, 0, 'S' },
1623 { "help", 0, 0, 'h' },
1624 { "group", 1, 0, 'g' },
1625 { "version", 0, 0, 'V' },
1626 { "quiet", 0, 0, 'q' },
1627 { "verbose", 0, 0, 'v' },
1628 { NULL, 0, 0, 0 }
1629 };
1630
1631 while (1) {
1632 int option_index = 0;
1633 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:E:C:", long_options, &option_index);
1634 if (c == -1) {
1635 break;
1636 }
1637
1638 switch (c) {
1639 case 0:
1640 fprintf(stderr, "option %s", long_options[option_index].name);
1641 if (optarg) {
1642 fprintf(stderr, " with arg %s\n", optarg);
1643 }
1644 break;
1645 case 'c':
1646 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
1647 break;
1648 case 'a':
1649 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
1650 break;
1651 case 'd':
1652 opt_daemon = 1;
1653 break;
1654 case 'g':
1655 opt_tracing_group = strdup(optarg);
1656 break;
1657 case 'h':
1658 usage();
1659 exit(EXIT_FAILURE);
1660 case 'V':
1661 fprintf(stdout, "%s\n", VERSION);
1662 exit(EXIT_SUCCESS);
1663 case 'S':
1664 opt_sig_parent = 1;
1665 break;
1666 case 'E':
1667 snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, "%s", optarg);
1668 break;
1669 case 'C':
1670 snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, "%s", optarg);
1671 break;
1672 case 'q':
1673 opt_quiet = 1;
1674 break;
1675 case 'v':
1676 opt_verbose = 1;
1677 break;
1678 default:
1679 /* Unknown option or other error.
1680 * Error is printed by getopt, just return */
1681 return -1;
1682 }
1683 }
1684
1685 return 0;
1686 }
1687
1688 /*
1689 * init_daemon_socket
1690 *
1691 * Creates the two needed socket by the daemon.
1692 * apps_sock - The communication socket for all UST apps.
1693 * client_sock - The communication of the cli tool (lttng).
1694 */
1695 static int init_daemon_socket()
1696 {
1697 int ret = 0;
1698 mode_t old_umask;
1699
1700 old_umask = umask(0);
1701
1702 /* Create client tool unix socket */
1703 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
1704 if (client_sock < 0) {
1705 ERR("Create unix sock failed: %s", client_unix_sock_path);
1706 ret = -1;
1707 goto end;
1708 }
1709
1710 /* File permission MUST be 660 */
1711 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1712 if (ret < 0) {
1713 ERR("Set file permissions failed: %s", client_unix_sock_path);
1714 perror("chmod");
1715 goto end;
1716 }
1717
1718 /* Create the application unix socket */
1719 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
1720 if (apps_sock < 0) {
1721 ERR("Create unix sock failed: %s", apps_unix_sock_path);
1722 ret = -1;
1723 goto end;
1724 }
1725
1726 /* File permission MUST be 666 */
1727 ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
1728 if (ret < 0) {
1729 ERR("Set file permissions failed: %s", apps_unix_sock_path);
1730 perror("chmod");
1731 goto end;
1732 }
1733
1734 end:
1735 umask(old_umask);
1736 return ret;
1737 }
1738
1739 /*
1740 * check_existing_daemon
1741 *
1742 * Check if the global socket is available.
1743 * If yes, error is returned.
1744 */
1745 static int check_existing_daemon()
1746 {
1747 int ret;
1748
1749 ret = access(client_unix_sock_path, F_OK);
1750 if (ret == 0) {
1751 ret = access(apps_unix_sock_path, F_OK);
1752 }
1753
1754 return ret;
1755 }
1756
1757 /*
1758 * set_permissions
1759 *
1760 * Set the tracing group gid onto the client socket.
1761 *
1762 * Race window between mkdir and chown is OK because we are going from
1763 * less permissive (root.root) to more permissive (root.tracing).
1764 */
1765 static int set_permissions(void)
1766 {
1767 int ret;
1768 struct group *grp;
1769
1770 /* Decide which group name to use */
1771 (opt_tracing_group != NULL) ?
1772 (grp = getgrnam(opt_tracing_group)) :
1773 (grp = getgrnam(default_tracing_group));
1774
1775 if (grp == NULL) {
1776 ERR("Missing tracing group. Aborting execution.\n");
1777 ret = -1;
1778 goto end;
1779 }
1780
1781 /* Set lttng run dir */
1782 ret = chown(LTTNG_RUNDIR, 0, grp->gr_gid);
1783 if (ret < 0) {
1784 ERR("Unable to set group on " LTTNG_RUNDIR);
1785 perror("chown");
1786 }
1787
1788 /* lttng client socket path */
1789 ret = chown(client_unix_sock_path, 0, grp->gr_gid);
1790 if (ret < 0) {
1791 ERR("Unable to set group on %s", client_unix_sock_path);
1792 perror("chown");
1793 }
1794
1795 /* kconsumerd error socket path */
1796 ret = chown(kconsumerd_err_unix_sock_path, 0, grp->gr_gid);
1797 if (ret < 0) {
1798 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path);
1799 perror("chown");
1800 }
1801
1802 DBG("All permissions are set");
1803
1804 end:
1805 return ret;
1806 }
1807
1808 /*
1809 * create_lttng_rundir
1810 *
1811 * Create the lttng run directory needed for all
1812 * global sockets and pipe.
1813 */
1814 static int create_lttng_rundir(void)
1815 {
1816 int ret;
1817
1818 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
1819 if (ret < 0) {
1820 if (errno != EEXIST) {
1821 ERR("Unable to create " LTTNG_RUNDIR);
1822 goto error;
1823 } else {
1824 ret = 0;
1825 }
1826 }
1827
1828 error:
1829 return ret;
1830 }
1831
1832 /*
1833 * set_kconsumerd_sockets
1834 *
1835 * Setup sockets and directory needed by the kconsumerd
1836 * communication with the session daemon.
1837 */
1838 static int set_kconsumerd_sockets(void)
1839 {
1840 int ret;
1841
1842 if (strlen(kconsumerd_err_unix_sock_path) == 0) {
1843 snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, KCONSUMERD_ERR_SOCK_PATH);
1844 }
1845
1846 if (strlen(kconsumerd_cmd_unix_sock_path) == 0) {
1847 snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, KCONSUMERD_CMD_SOCK_PATH);
1848 }
1849
1850 ret = mkdir(KCONSUMERD_PATH, S_IRWXU | S_IRWXG);
1851 if (ret < 0) {
1852 if (errno != EEXIST) {
1853 ERR("Failed to create " KCONSUMERD_PATH);
1854 goto error;
1855 }
1856 ret = 0;
1857 }
1858
1859 /* Create the kconsumerd error unix socket */
1860 kconsumerd_err_sock = lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path);
1861 if (kconsumerd_err_sock < 0) {
1862 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path);
1863 ret = -1;
1864 goto error;
1865 }
1866
1867 /* File permission MUST be 660 */
1868 ret = chmod(kconsumerd_err_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1869 if (ret < 0) {
1870 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path);
1871 perror("chmod");
1872 goto error;
1873 }
1874
1875 error:
1876 return ret;
1877 }
1878
1879 /*
1880 * sighandler
1881 *
1882 * Signal handler for the daemon
1883 */
1884 static void sighandler(int sig)
1885 {
1886 switch (sig) {
1887 case SIGPIPE:
1888 DBG("SIGPIPE catched");
1889 return;
1890 case SIGINT:
1891 DBG("SIGINT catched");
1892 cleanup();
1893 break;
1894 case SIGTERM:
1895 DBG("SIGTERM catched");
1896 cleanup();
1897 break;
1898 default:
1899 break;
1900 }
1901
1902 exit(EXIT_SUCCESS);
1903 }
1904
1905 /*
1906 * set_signal_handler
1907 *
1908 * Setup signal handler for :
1909 * SIGINT, SIGTERM, SIGPIPE
1910 */
1911 static int set_signal_handler(void)
1912 {
1913 int ret = 0;
1914 struct sigaction sa;
1915 sigset_t sigset;
1916
1917 if ((ret = sigemptyset(&sigset)) < 0) {
1918 perror("sigemptyset");
1919 return ret;
1920 }
1921
1922 sa.sa_handler = sighandler;
1923 sa.sa_mask = sigset;
1924 sa.sa_flags = 0;
1925 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
1926 perror("sigaction");
1927 return ret;
1928 }
1929
1930 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
1931 perror("sigaction");
1932 return ret;
1933 }
1934
1935 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
1936 perror("sigaction");
1937 return ret;
1938 }
1939
1940 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
1941
1942 return ret;
1943 }
1944
1945 /*
1946 * set_ulimit
1947 *
1948 * Set open files limit to unlimited. This daemon can open a large number of
1949 * file descriptors in order to consumer multiple kernel traces.
1950 */
1951 static void set_ulimit(void)
1952 {
1953 int ret;
1954 struct rlimit lim;
1955
1956 lim.rlim_cur = 65535;
1957 lim.rlim_max = 65535;
1958
1959 ret = setrlimit(RLIMIT_NOFILE, &lim);
1960 if (ret < 0) {
1961 perror("failed to set open files limit");
1962 }
1963 }
1964
1965 /*
1966 * main
1967 */
1968 int main(int argc, char **argv)
1969 {
1970 int ret = 0;
1971 void *status;
1972 const char *home_path;
1973
1974 /* Parse arguments */
1975 progname = argv[0];
1976 if ((ret = parse_args(argc, argv) < 0)) {
1977 goto error;
1978 }
1979
1980 /* Daemonize */
1981 if (opt_daemon) {
1982 ret = daemon(0, 0);
1983 if (ret < 0) {
1984 perror("daemon");
1985 goto error;
1986 }
1987 }
1988
1989 /* Check if daemon is UID = 0 */
1990 is_root = !getuid();
1991
1992 /* Set all sockets path */
1993 if (is_root) {
1994 ret = create_lttng_rundir();
1995 if (ret < 0) {
1996 goto error;
1997 }
1998
1999 if (strlen(apps_unix_sock_path) == 0) {
2000 snprintf(apps_unix_sock_path, PATH_MAX,
2001 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
2002 }
2003
2004 if (strlen(client_unix_sock_path) == 0) {
2005 snprintf(client_unix_sock_path, PATH_MAX,
2006 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
2007 }
2008
2009 ret = set_kconsumerd_sockets();
2010 if (ret < 0) {
2011 goto error;
2012 }
2013
2014 /* Setup kernel tracer */
2015 init_kernel_tracer();
2016
2017 /* Set ulimit for open files */
2018 set_ulimit();
2019 } else {
2020 home_path = get_home_dir();
2021 if (home_path == NULL) {
2022 ERR("Can't get HOME directory for sockets creation.\n \
2023 Please specify --socket PATH.");
2024 goto error;
2025 }
2026
2027 if (strlen(apps_unix_sock_path) == 0) {
2028 snprintf(apps_unix_sock_path, PATH_MAX,
2029 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
2030 }
2031
2032 /* Set the cli tool unix socket path */
2033 if (strlen(client_unix_sock_path) == 0) {
2034 snprintf(client_unix_sock_path, PATH_MAX,
2035 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
2036 }
2037 }
2038
2039 DBG("Client socket path %s", client_unix_sock_path);
2040 DBG("Application socket path %s", apps_unix_sock_path);
2041
2042 /* See if daemon already exist. If any of the two
2043 * socket needed by the daemon are present, this test fails
2044 */
2045 if ((ret = check_existing_daemon()) == 0) {
2046 ERR("Already running daemon.\n");
2047 /* We do not goto error because we must not
2048 * cleanup() because a daemon is already running.
2049 */
2050 exit(EXIT_FAILURE);
2051 }
2052
2053 if (set_signal_handler() < 0) {
2054 goto error;
2055 }
2056
2057 /* Setup the needed unix socket */
2058 if (init_daemon_socket() < 0) {
2059 goto error;
2060 }
2061
2062 /* Set credentials to socket */
2063 if (is_root && (set_permissions() < 0)) {
2064 goto error;
2065 }
2066
2067 /* Get parent pid if -S, --sig-parent is specified. */
2068 if (opt_sig_parent) {
2069 ppid = getppid();
2070 }
2071
2072 while (1) {
2073 /* Create thread to manage the client socket */
2074 ret = pthread_create(&client_thread, NULL, thread_manage_clients, (void *) NULL);
2075 if (ret != 0) {
2076 perror("pthread_create");
2077 goto error;
2078 }
2079
2080 /* Create thread to manage application socket */
2081 ret = pthread_create(&apps_thread, NULL, thread_manage_apps, (void *) NULL);
2082 if (ret != 0) {
2083 perror("pthread_create");
2084 goto error;
2085 }
2086
2087 ret = pthread_join(client_thread, &status);
2088 if (ret != 0) {
2089 perror("pthread_join");
2090 goto error;
2091 }
2092 }
2093
2094 cleanup();
2095 exit(EXIT_SUCCESS);
2096
2097 error:
2098 cleanup();
2099 exit(EXIT_FAILURE);
2100 }
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