Fix comment
[lttng-tools.git] / ltt-sessiond / main.c
CommitLineData
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1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
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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.
91d76f53 8 *
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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.
91d76f53 13 *
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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.
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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>
8c0faa1d 25#include <semaphore.h>
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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>
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35#include <sys/time.h>
36#include <sys/resource.h>
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37#include <unistd.h>
38
39#include <urcu/list.h> /* URCU list library (-lurcu) */
5b97ec60 40#include <lttng/lttng.h>
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41
42#include "liblttsessiondcomm.h"
43#include "ltt-sessiond.h"
75462a81 44#include "lttngerr.h"
20fe2104 45#include "kernel-ctl.h"
9e78d6ae 46#include "ust-ctl.h"
5b74c7b1 47#include "session.h"
91d76f53 48#include "traceable-app.h"
5dc18550 49#include "lttng-kconsumerd.h"
62d3069f 50#include "libustctl.h"
fac6795d 51
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52/*
53 * TODO:
54 * teardown: signal SIGTERM handler -> write into pipe. Threads waits
55 * with epoll on pipe and on other pipes/sockets for commands. Main
56 * simply waits on pthread join.
57 */
58
75462a81 59/* Const values */
686204ab 60const char default_home_dir[] = DEFAULT_HOME_DIR;
64a23ac4 61const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
686204ab
MD
62const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
63const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
64
fac6795d 65/* Variables */
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66int opt_verbose; /* Not static for lttngerr.h */
67int opt_quiet; /* Not static for lttngerr.h */
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68const char *progname;
69const char *opt_tracing_group;
5b8719f5 70static int opt_sig_parent;
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71static int opt_daemon;
72static int is_root; /* Set to 1 if the daemon is running as root */
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73static pid_t ppid; /* Parent PID for --sig-parent option */
74static pid_t kconsumerd_pid;
fac6795d 75
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76static char apps_unix_sock_path[PATH_MAX]; /* Global application Unix socket path */
77static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */
78static char kconsumerd_err_unix_sock_path[PATH_MAX]; /* kconsumerd error Unix socket path */
79static char kconsumerd_cmd_unix_sock_path[PATH_MAX]; /* kconsumerd command Unix socket path */
fac6795d 80
1d4b027a 81/* Sockets and FDs */
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82static int client_sock;
83static int apps_sock;
84static int kconsumerd_err_sock;
8c0faa1d 85static int kconsumerd_cmd_sock;
20fe2104 86static int kernel_tracer_fd;
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87
88/* Pthread, Mutexes and Semaphores */
8c0faa1d 89static pthread_t kconsumerd_thread;
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90static pthread_t apps_thread;
91static pthread_t client_thread;
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92static sem_t kconsumerd_sem;
93
1d4b027a 94static pthread_mutex_t kconsumerd_pid_mutex; /* Mutex to control kconsumerd pid assignation */
fac6795d 95
fac6795d 96/*
1d4b027a 97 * teardown_kernel_session
fac6795d 98 *
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99 * Complete teardown of a kernel session. This free all data structure
100 * related to a kernel session and update counter.
fac6795d 101 */
1d4b027a 102static void teardown_kernel_session(struct ltt_session *session)
fac6795d 103{
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104 if (session->kernel_session != NULL) {
105 DBG("Tearing down kernel session");
c363b55d 106 trace_destroy_kernel_session(session->kernel_session);
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107 /* Extra precaution */
108 session->kernel_session = NULL;
109 /* Decrement session count */
110 session->kern_session_count--;
fac6795d 111 }
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112}
113
114/*
1d4b027a 115 * cleanup
fac6795d 116 *
1d4b027a 117 * Cleanup the daemon on exit
fac6795d 118 */
1d4b027a 119static void cleanup()
fac6795d 120{
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121 int ret;
122 char *cmd;
123 struct ltt_session *sess;
fac6795d 124
1d4b027a 125 DBG("Cleaning up");
e07ae692 126
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127 /* <fun> */
128 MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
129 MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0);
130 /* </fun> */
fac6795d 131
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132 /* Stopping all threads */
133 DBG("Terminating all threads");
134 pthread_cancel(client_thread);
135 pthread_cancel(apps_thread);
136 if (kconsumerd_pid != 0) {
137 pthread_cancel(kconsumerd_thread);
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138 }
139
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140 DBG("Unlinking all unix socket");
141 unlink(client_unix_sock_path);
142 unlink(apps_unix_sock_path);
143 unlink(kconsumerd_err_unix_sock_path);
fac6795d 144
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145 DBG("Removing %s directory", LTTNG_RUNDIR);
146 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
147 if (ret < 0) {
148 ERR("asprintf failed. Something is really wrong!");
149 }
5461b305 150
1d4b027a
DG
151 /* Remove lttng run directory */
152 ret = system(cmd);
153 if (ret < 0) {
154 ERR("Unable to clean " LTTNG_RUNDIR);
155 }
5461b305 156
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157 DBG("Cleaning up all session");
158 /* Cleanup ALL session */
159 cds_list_for_each_entry(sess, &ltt_session_list.head, list) {
160 teardown_kernel_session(sess);
161 // TODO complete session cleanup (including UST)
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162 }
163
f3ed775e 164 DBG("Closing kernel fd");
1d4b027a 165 close(kernel_tracer_fd);
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166}
167
e065084a
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168/*
169 * send_unix_sock
170 *
171 * Send data on a unix socket using the liblttsessiondcomm API.
172 *
173 * Return lttcomm error code.
174 */
175static int send_unix_sock(int sock, void *buf, size_t len)
176{
177 /* Check valid length */
178 if (len <= 0) {
179 return -1;
180 }
181
182 return lttcomm_send_unix_sock(sock, buf, len);
183}
184
5461b305
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185/*
186 * clean_command_ctx
187 *
188 * Free memory of a command context structure.
189 */
190static void clean_command_ctx(struct command_ctx *cmd_ctx)
191{
192 DBG("Clean command context structure %p", cmd_ctx);
193 if (cmd_ctx) {
194 if (cmd_ctx->llm) {
195 free(cmd_ctx->llm);
196 }
197 if (cmd_ctx->lsm) {
198 free(cmd_ctx->lsm);
199 }
200 free(cmd_ctx);
201 cmd_ctx = NULL;
202 }
203}
204
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205/*
206 * send_kconsumerd_fds
207 *
208 * Send all stream fds of the kernel session to the consumer.
209 */
210static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session)
211{
212 int ret;
213 size_t nb_fd;
214 struct ltt_kernel_stream *stream;
215 struct ltt_kernel_channel *chan;
216 struct lttcomm_kconsumerd_header lkh;
217 struct lttcomm_kconsumerd_msg lkm;
218
219 nb_fd = session->stream_count_global;
220
221 /* Setup header */
222 lkh.payload_size = (nb_fd + 1) * sizeof(struct lttcomm_kconsumerd_msg);
223 lkh.cmd_type = ADD_STREAM;
224
225 DBG("Sending kconsumerd header");
226
227 ret = lttcomm_send_unix_sock(sock, &lkh, sizeof(struct lttcomm_kconsumerd_header));
228 if (ret < 0) {
229 perror("send kconsumerd header");
230 goto error;
231 }
232
233 DBG("Sending metadata stream fd");
234
235 /* Send metadata stream fd first */
236 lkm.fd = session->metadata_stream_fd;
237 lkm.state = ACTIVE_FD;
238 lkm.max_sb_size = session->metadata->conf->attr.subbuf_size;
239 strncpy(lkm.path_name, session->metadata->pathname, PATH_MAX);
240
241 ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
242 if (ret < 0) {
243 perror("send kconsumerd fd");
244 goto error;
245 }
246
247 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
248 cds_list_for_each_entry(stream, &chan->stream_list.head, list) {
249 lkm.fd = stream->fd;
250 lkm.state = stream->state;
251 lkm.max_sb_size = chan->channel->attr.subbuf_size;
252 strncpy(lkm.path_name, stream->pathname, PATH_MAX);
253
254 DBG("Sending fd %d to kconsumerd", lkm.fd);
255
256 ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
257 if (ret < 0) {
258 perror("send kconsumerd fd");
259 goto error;
260 }
261 }
262 }
263
264 DBG("Kconsumerd fds sent");
265
266 return 0;
267
268error:
269 return ret;
270}
271
272/*
273 * create_trace_dir
274 *
275 * Create the trace output directory.
276 */
277static int create_trace_dir(struct ltt_kernel_session *session)
278{
279 int ret;
280 struct ltt_kernel_channel *chan;
281
282 /* Create all channel directories */
283 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
284 DBG("Creating trace directory at %s", chan->pathname);
285 // TODO: recursive create dir
286 ret = mkdir(chan->pathname, S_IRWXU | S_IRWXG );
287 if (ret < 0) {
288 if (ret != EEXIST) {
289 perror("mkdir trace path");
290 ret = -errno;
291 goto error;
292 }
293 }
294 }
295
296 return 0;
297
298error:
299 return ret;
300}
301
fac6795d 302/*
471d1693 303 * ust_connect_app
fac6795d
DG
304 *
305 * Return a socket connected to the libust communication socket
306 * of the application identified by the pid.
379473d2
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307 *
308 * If the pid is not found in the traceable list,
309 * return -1 to indicate error.
fac6795d 310 */
471d1693 311static int ust_connect_app(pid_t pid)
fac6795d 312{
91d76f53
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313 int sock;
314 struct ltt_traceable_app *lta;
379473d2 315
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316 DBG("Connect to application pid %d", pid);
317
91d76f53
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318 lta = find_app_by_pid(pid);
319 if (lta == NULL) {
320 /* App not found */
7442b2ba 321 DBG("Application pid %d not found", pid);
379473d2
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322 return -1;
323 }
fac6795d 324
91d76f53 325 sock = ustctl_connect_pid(lta->pid);
fac6795d 326 if (sock < 0) {
62d3069f 327 ERR("Fail connecting to the PID %d", pid);
fac6795d
DG
328 }
329
330 return sock;
331}
332
333/*
334 * notify_apps
335 *
336 * Notify apps by writing 42 to a named pipe using name.
337 * Every applications waiting for a ltt-sessiond will be notified
338 * and re-register automatically to the session daemon.
339 *
340 * Return open or write error value.
341 */
342static int notify_apps(const char *name)
343{
344 int fd;
345 int ret = -1;
346
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347 DBG("Notify the global application pipe");
348
fac6795d
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349 /* Try opening the global pipe */
350 fd = open(name, O_WRONLY);
351 if (fd < 0) {
352 goto error;
353 }
354
355 /* Notify by writing on the pipe */
356 ret = write(fd, "42", 2);
357 if (ret < 0) {
358 perror("write");
359 }
360
361error:
362 return ret;
363}
364
e065084a 365/*
5461b305 366 * setup_lttng_msg
ca95a216 367 *
5461b305
DG
368 * Setup the outgoing data buffer for the response (llm) by allocating the
369 * right amount of memory and copying the original information from the lsm
370 * structure.
ca95a216
DG
371 *
372 * Return total size of the buffer pointed by buf.
373 */
5461b305 374static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
ca95a216 375{
f3ed775e 376 int ret, buf_size;
ca95a216 377
f3ed775e 378 buf_size = size;
5461b305
DG
379
380 cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
381 if (cmd_ctx->llm == NULL) {
ca95a216 382 perror("malloc");
5461b305 383 ret = -ENOMEM;
ca95a216
DG
384 goto error;
385 }
386
5461b305
DG
387 /* Copy common data */
388 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
389 cmd_ctx->llm->pid = cmd_ctx->lsm->pid;
5461b305 390
5461b305
DG
391 cmd_ctx->llm->data_size = size;
392 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
393
ca95a216
DG
394 return buf_size;
395
396error:
397 return ret;
398}
399
1d4b027a
DG
400/*
401 * thread_manage_kconsumerd
402 *
403 * This thread manage the kconsumerd error sent
404 * back to the session daemon.
405 */
406static void *thread_manage_kconsumerd(void *data)
407{
408 int sock, ret;
409 enum lttcomm_return_code code;
410
411 DBG("[thread] Manage kconsumerd started");
412
413 ret = lttcomm_listen_unix_sock(kconsumerd_err_sock);
414 if (ret < 0) {
415 goto error;
416 }
417
418 sock = lttcomm_accept_unix_sock(kconsumerd_err_sock);
419 if (sock < 0) {
420 goto error;
421 }
422
712ea556 423 /* Getting status code from kconsumerd */
1d4b027a
DG
424 ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
425 if (ret <= 0) {
426 goto error;
427 }
428
429 if (code == KCONSUMERD_COMMAND_SOCK_READY) {
430 kconsumerd_cmd_sock = lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path);
431 if (kconsumerd_cmd_sock < 0) {
712ea556 432 sem_post(&kconsumerd_sem);
1d4b027a
DG
433 perror("kconsumerd connect");
434 goto error;
435 }
436 /* Signal condition to tell that the kconsumerd is ready */
437 sem_post(&kconsumerd_sem);
438 DBG("Kconsumerd command socket ready");
439 } else {
6f61d021 440 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
1d4b027a
DG
441 lttcomm_get_readable_code(-code));
442 goto error;
443 }
444
712ea556
DG
445 /* Wait for any kconsumerd error */
446 ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
447 if (ret <= 0) {
448 ERR("Kconsumerd closed the command socket");
449 goto error;
6f61d021 450 }
1d4b027a 451
712ea556
DG
452 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code));
453
1d4b027a
DG
454error:
455 kconsumerd_pid = 0;
6f61d021 456 DBG("Kconsumerd thread dying");
1d4b027a
DG
457 return NULL;
458}
459
460/*
461 * thread_manage_apps
462 *
463 * This thread manage the application socket communication
464 */
465static void *thread_manage_apps(void *data)
466{
467 int sock, ret;
468
469 /* TODO: Something more elegant is needed but fine for now */
470 /* FIXME: change all types to either uint8_t, uint32_t, uint64_t
471 * for 32-bit vs 64-bit compat processes. */
472 /* replicate in ust with version number */
473 struct {
474 int reg; /* 1:register, 0:unregister */
475 pid_t pid;
476 uid_t uid;
477 } reg_msg;
478
479 DBG("[thread] Manage apps started");
480
481 ret = lttcomm_listen_unix_sock(apps_sock);
482 if (ret < 0) {
483 goto error;
484 }
485
486 /* Notify all applications to register */
487 notify_apps(default_global_apps_pipe);
488
489 while (1) {
490 DBG("Accepting application registration");
491 /* Blocking call, waiting for transmission */
492 sock = lttcomm_accept_unix_sock(apps_sock);
493 if (sock < 0) {
494 goto error;
495 }
496
497 /* Basic recv here to handle the very simple data
498 * that the libust send to register (reg_msg).
499 */
500 ret = recv(sock, &reg_msg, sizeof(reg_msg), 0);
501 if (ret < 0) {
502 perror("recv");
503 continue;
504 }
505
506 /* Add application to the global traceable list */
507 if (reg_msg.reg == 1) {
508 /* Registering */
509 ret = register_traceable_app(reg_msg.pid, reg_msg.uid);
510 if (ret < 0) {
511 /* register_traceable_app only return an error with
512 * ENOMEM. At this point, we better stop everything.
513 */
514 goto error;
515 }
516 } else {
517 /* Unregistering */
518 unregister_traceable_app(reg_msg.pid);
519 }
520 }
521
522error:
523
524 return NULL;
525}
526
8c0faa1d 527/*
693bd40b 528 * spawn_kconsumerd_thread
8c0faa1d
DG
529 *
530 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
531 * exec or it will fails.
532 */
693bd40b 533static int spawn_kconsumerd_thread(void)
8c0faa1d
DG
534{
535 int ret;
536
537 /* Setup semaphore */
538 sem_init(&kconsumerd_sem, 0, 0);
539
1d4b027a 540 ret = pthread_create(&kconsumerd_thread, NULL, thread_manage_kconsumerd, (void *) NULL);
8c0faa1d
DG
541 if (ret != 0) {
542 perror("pthread_create kconsumerd");
543 goto error;
544 }
545
693bd40b 546 /* Wait for the kconsumerd thread to be ready */
8c0faa1d
DG
547 sem_wait(&kconsumerd_sem);
548
712ea556
DG
549 if (kconsumerd_pid == 0) {
550 ERR("Kconsumerd did not start");
551 goto error;
552 }
553
8c0faa1d
DG
554 return 0;
555
556error:
712ea556 557 ret = LTTCOMM_KERN_CONSUMER_FAIL;
8c0faa1d
DG
558 return ret;
559}
560
561/*
693bd40b 562 * spawn_kconsumerd
8c0faa1d 563 *
693bd40b
DG
564 * Fork and exec a kernel consumer daemon (kconsumerd).
565 *
566 * NOTE: It is very important to fork a kconsumerd BEFORE opening any kernel
567 * file descriptor using the libkernelctl or kernel-ctl functions. So, a
568 * kernel consumer MUST only be spawned before creating a kernel session.
8c0faa1d
DG
569 *
570 * Return pid if successful else -1.
571 */
693bd40b 572static pid_t spawn_kconsumerd(void)
8c0faa1d
DG
573{
574 int ret;
575 pid_t pid;
576
c49dc785
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577 DBG("Spawning kconsumerd");
578
8c0faa1d
DG
579 pid = fork();
580 if (pid == 0) {
581 /*
582 * Exec kconsumerd.
583 */
f57244de 584 execlp("kconsumerd", "kconsumerd", "--verbose", NULL);
8c0faa1d
DG
585 if (errno != 0) {
586 perror("kernel start consumer exec");
587 }
588 exit(EXIT_FAILURE);
589 } else if (pid > 0) {
590 ret = pid;
591 goto error;
592 } else {
593 perror("kernel start consumer fork");
594 ret = -errno;
595 goto error;
596 }
597
598error:
599 return ret;
600}
601
693bd40b
DG
602/*
603 * start_kconsumerd
604 *
605 * Spawn the kconsumerd daemon and session daemon thread.
606 */
607static int start_kconsumerd(void)
608{
609 int ret;
610
693bd40b 611 pthread_mutex_lock(&kconsumerd_pid_mutex);
c49dc785
DG
612 if (kconsumerd_pid != 0) {
613 goto end;
614 }
693bd40b 615
c49dc785
DG
616 ret = spawn_kconsumerd();
617 if (ret < 0) {
618 ERR("Spawning kconsumerd failed");
619 ret = LTTCOMM_KERN_CONSUMER_FAIL;
620 pthread_mutex_unlock(&kconsumerd_pid_mutex);
621 goto error;
693bd40b 622 }
c49dc785
DG
623
624 /* Setting up the global kconsumerd_pid */
625 kconsumerd_pid = ret;
693bd40b
DG
626 pthread_mutex_unlock(&kconsumerd_pid_mutex);
627
6f61d021
DG
628 DBG("Kconsumerd pid %d", ret);
629
693bd40b 630 DBG("Spawning kconsumerd thread");
693bd40b
DG
631 ret = spawn_kconsumerd_thread();
632 if (ret < 0) {
633 ERR("Fatal error spawning kconsumerd thread");
693bd40b
DG
634 goto error;
635 }
636
c49dc785
DG
637end:
638 pthread_mutex_unlock(&kconsumerd_pid_mutex);
693bd40b
DG
639 return 0;
640
641error:
642 return ret;
643}
644
8c0faa1d 645/*
f3ed775e 646 * init_kernel_tracer
8c0faa1d 647 *
f3ed775e 648 * Setup necessary data for kernel tracer action.
8c0faa1d 649 */
f3ed775e 650static void init_kernel_tracer(void)
8c0faa1d 651{
f3ed775e
DG
652 /* Set the global kernel tracer fd */
653 kernel_tracer_fd = open(DEFAULT_KERNEL_TRACER_PATH, O_RDWR);
654 if (kernel_tracer_fd < 0) {
655 WARN("No kernel tracer available");
656 kernel_tracer_fd = 0;
8c0faa1d
DG
657 }
658
f3ed775e
DG
659 DBG("Kernel tracer fd %d", kernel_tracer_fd);
660}
33a2b854 661
f3ed775e
DG
662/*
663 * start_kernel_trace
664 *
665 * Start tracing by creating trace directory and sending FDs to the kernel
666 * consumer.
667 */
668static int start_kernel_trace(struct ltt_kernel_session *session)
669{
670 int ret;
8c0faa1d 671
f3ed775e
DG
672 /* Create trace directory */
673 ret = create_trace_dir(session);
1d4b027a 674 if (ret < 0) {
f3ed775e
DG
675 if (ret == -EEXIST) {
676 ret = LTTCOMM_KERN_DIR_EXIST;
677 } else {
678 ret = LTTCOMM_KERN_DIR_FAIL;
679 goto error;
33a2b854
DG
680 }
681 }
682
f3ed775e
DG
683 if (session->kconsumer_fds_sent == 0) {
684 ret = send_kconsumerd_fds(kconsumerd_cmd_sock, session);
685 if (ret < 0) {
686 ERR("Send kconsumerd fds failed");
687 ret = LTTCOMM_KERN_CONSUMER_FAIL;
688 goto error;
689 }
1d4b027a 690
f3ed775e
DG
691 session->kconsumer_fds_sent = 1;
692 }
1d4b027a
DG
693
694error:
695 return ret;
8c0faa1d
DG
696}
697
698/*
f3ed775e 699 * init_default_channel
8c0faa1d 700 *
f3ed775e 701 * Allocate a channel structure and fill it.
8c0faa1d 702 */
f3ed775e 703static struct lttng_channel *init_default_channel(void)
8c0faa1d 704{
f3ed775e 705 struct lttng_channel *chan;
1d4b027a 706
f3ed775e
DG
707 chan = malloc(sizeof(struct lttng_channel));
708 if (chan == NULL) {
709 perror("init channel malloc");
710 goto error;
8c0faa1d 711 }
1d4b027a 712
f3ed775e
DG
713 if (snprintf(chan->name, NAME_MAX, DEFAULT_CHANNEL_NAME) < 0) {
714 perror("snprintf defautl channel name");
715 return NULL;
716 }
717
718 chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
719 chan->attr.subbuf_size = DEFAULT_CHANNEL_SUBBUF_SIZE;
720 chan->attr.num_subbuf = DEFAULT_CHANNEL_SUBBUF_NUM;
721 chan->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
722 chan->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
1d4b027a
DG
723
724error:
f3ed775e 725 return chan;
8c0faa1d
DG
726}
727
333f285e 728/*
f3ed775e 729 * create_kernel_session
333f285e 730 *
f3ed775e 731 * Create a kernel tracer session then create the default channel.
333f285e 732 */
f3ed775e 733static int create_kernel_session(struct ltt_session *session)
333f285e 734{
f3ed775e
DG
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;
333f285e
DG
744 }
745
f3ed775e
DG
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);
755 if (ret < 0) {
756 ret = LTTCOMM_KERN_CHAN_FAIL;
757 goto error;
758 }
759
760error:
761 return ret;
333f285e
DG
762}
763
fac6795d
DG
764/*
765 * process_client_msg
766 *
5461b305
DG
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.
fac6795d 770 *
e065084a 771 * Return any error encountered or 0 for success.
fac6795d 772 */
5461b305 773static int process_client_msg(struct command_ctx *cmd_ctx)
fac6795d 774{
5461b305 775 int ret;
fac6795d 776
5461b305 777 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
fac6795d 778
f3ed775e 779 /* Listing commands don't need a session */
5461b305 780 switch (cmd_ctx->lsm->cmd_type) {
5e16da05
MD
781 case LTTNG_CREATE_SESSION:
782 case LTTNG_LIST_SESSIONS:
f3ed775e
DG
783 case LTTNG_LIST_EVENTS:
784 case LTTNG_KERNEL_LIST_EVENTS:
785 case LTTNG_LIST_TRACEABLE_APPS:
5e16da05
MD
786 break;
787 default:
f3ed775e
DG
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);
5461b305 790 if (cmd_ctx->session == NULL) {
f3ed775e
DG
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 }
5461b305 797 goto error;
379473d2 798 }
5e16da05 799 break;
379473d2
DG
800 }
801
f3ed775e
DG
802 /*
803 * Check kernel command for kernel session.
804 */
20fe2104 805 switch (cmd_ctx->lsm->cmd_type) {
f3ed775e
DG
806 case LTTNG_KERNEL_CREATE_CHANNEL:
807 case LTTNG_KERNEL_DISABLE_ALL_EVENT:
808 case LTTNG_KERNEL_DISABLE_CHANNEL:
809 case LTTNG_KERNEL_DISABLE_EVENT:
810 case LTTNG_KERNEL_ENABLE_ALL_EVENT:
811 case LTTNG_KERNEL_ENABLE_CHANNEL:
812 case LTTNG_KERNEL_ENABLE_EVENT:
813 case LTTNG_KERNEL_LIST_EVENTS:
333f285e 814 /* Kernel tracer check */
20fe2104 815 if (kernel_tracer_fd == 0) {
333f285e
DG
816 init_kernel_tracer();
817 if (kernel_tracer_fd == 0) {
818 ret = LTTCOMM_KERN_NA;
819 goto error;
820 }
20fe2104 821 }
f3ed775e
DG
822
823 /* Need a session for kernel command */
824 if (cmd_ctx->lsm->cmd_type != LTTNG_KERNEL_LIST_EVENTS &&
825 cmd_ctx->session->kernel_session == NULL) {
7b395890 826
f3ed775e
DG
827 ret = create_kernel_session(cmd_ctx->session);
828 if (ret < 0) {
829 ret = LTTCOMM_KERN_SESS_FAIL;
830 goto error;
831 }
832
7b395890 833 /* Start the kernel consumer daemon */
f3ed775e
DG
834 if (kconsumerd_pid == 0) {
835 ret = start_kconsumerd();
836 if (ret < 0) {
837 goto error;
838 }
839 }
840 }
20fe2104
DG
841 }
842
471d1693 843 /* Connect to ust apps if available pid */
5461b305 844 if (cmd_ctx->lsm->pid > 0) {
471d1693 845 /* Connect to app using ustctl API */
5461b305
DG
846 cmd_ctx->ust_sock = ust_connect_app(cmd_ctx->lsm->pid);
847 if (cmd_ctx->ust_sock < 0) {
471d1693 848 ret = LTTCOMM_NO_TRACEABLE;
5461b305 849 goto error;
471d1693
DG
850 }
851 }
852
fac6795d 853 /* Process by command type */
5461b305 854 switch (cmd_ctx->lsm->cmd_type) {
f3ed775e 855 case LTTNG_KERNEL_CREATE_CHANNEL:
20fe2104 856 {
f3ed775e 857 /* Setup lttng message with no payload */
20fe2104
DG
858 ret = setup_lttng_msg(cmd_ctx, 0);
859 if (ret < 0) {
860 goto setup_error;
861 }
862
f3ed775e 863 /* Kernel tracer */
8c0faa1d
DG
864 DBG("Creating kernel channel");
865
f3ed775e
DG
866 ret = kernel_create_channel(cmd_ctx->session->kernel_session,
867 &cmd_ctx->lsm->u.channel.chan);
20fe2104
DG
868 if (ret < 0) {
869 ret = LTTCOMM_KERN_CHAN_FAIL;
870 goto error;
871 }
872
873 ret = LTTCOMM_OK;
874 break;
875 }
e953ef25
DG
876 case LTTNG_KERNEL_DISABLE_EVENT:
877 {
878 int found = 0;
879 struct ltt_kernel_channel *chan;
880
881 /* Setup lttng message with no payload */
882 ret = setup_lttng_msg(cmd_ctx, 0);
883 if (ret < 0) {
884 goto setup_error;
885 }
886
887 /* Get channel by name and create event for that channel */
888 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
889 if (strcmp(cmd_ctx->lsm->u.disable.channel_name, chan->channel->name) == 0) {
890 DBG("Disabling kernel event %s for channel %s.",
891 cmd_ctx->lsm->u.disable.name, cmd_ctx->lsm->u.disable.channel_name);
892
893 ret = kernel_disable_event(cmd_ctx->lsm->u.disable.name, chan);
894 if (ret < 0) {
895 ret = LTTCOMM_KERN_DISABLE_FAIL;
896 goto error;
897 }
898 found = 1;
899 break;
900 }
901 }
902
903 if (!found) {
904 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
905 } else {
906 kernel_wait_quiescent(kernel_tracer_fd);
907 ret = LTTCOMM_OK;
908 }
909 break;
910 }
f3ed775e 911 case LTTNG_KERNEL_ENABLE_EVENT:
894be886 912 {
f3ed775e
DG
913 int found = 0;
914 struct ltt_kernel_channel *chan;
915
894be886
DG
916 /* Setup lttng message with no payload */
917 ret = setup_lttng_msg(cmd_ctx, 0);
918 if (ret < 0) {
919 goto setup_error;
920 }
921
f3ed775e
DG
922 /* Get channel by name and create event for that channel */
923 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
924 if (strcmp(cmd_ctx->lsm->u.enable.channel_name, chan->channel->name) == 0) {
925 DBG("Creating kernel event %s for channel %s.",
926 cmd_ctx->lsm->u.enable.event.name, cmd_ctx->lsm->u.enable.channel_name);
927
928 ret = kernel_create_event(chan, &cmd_ctx->lsm->u.enable.event);
929 if (ret < 0) {
930 ret = LTTCOMM_KERN_ENABLE_FAIL;
931 goto error;
932 }
933 found = 1;
934 break;
935 }
f34daff7
DG
936 }
937
f3ed775e
DG
938 if (!found) {
939 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
940 } else {
941 kernel_wait_quiescent(kernel_tracer_fd);
942 ret = LTTCOMM_OK;
943 }
894be886
DG
944 break;
945 }
f3ed775e 946 case LTTNG_KERNEL_ENABLE_ALL_EVENT:
33a2b854 947 {
f3ed775e 948 int pos, size, found;
33a2b854 949 char *event_list, *event, *ptr;
f3ed775e
DG
950 struct ltt_kernel_channel *chan;
951 struct lttng_event ev;
33a2b854
DG
952
953 /* Setup lttng message with no payload */
954 ret = setup_lttng_msg(cmd_ctx, 0);
955 if (ret < 0) {
956 goto setup_error;
957 }
958
959 DBG("Enabling all kernel event");
960
961 size = kernel_list_events(kernel_tracer_fd, &event_list);
962 if (size < 0) {
963 ret = LTTCOMM_KERN_LIST_FAIL;
964 goto error;
965 }
966
f3ed775e
DG
967 /* Get channel by name and create event for that channel */
968 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
969 if (strcmp(cmd_ctx->lsm->u.enable.channel_name, chan->channel->name) == 0) {
970 found = 1;
971 break;
972 }
973 }
974
975 if (!found) {
976 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
977 goto error;
978 }
979
33a2b854
DG
980 ptr = event_list;
981 while ((size = sscanf(ptr, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) {
f3ed775e
DG
982 strncpy(ev.name, event, LTTNG_SYM_NAME_LEN);
983 /* Default event type for enable all */
984 ev.type = LTTNG_EVENT_TRACEPOINTS;
985 /* Enable each single tracepoint event */
986 ret = kernel_create_event(chan, &ev);
33a2b854
DG
987 if (ret < 0) {
988 ret = LTTCOMM_KERN_ENABLE_FAIL;
989 goto error;
990 }
991 /* Move pointer to the next line */
992 ptr += pos + 1;
993 free(event);
994 }
995
996 free(event_list);
997
f3ed775e
DG
998 /* Quiescent wait after event enable */
999 kernel_wait_quiescent(kernel_tracer_fd);
33a2b854
DG
1000 ret = LTTCOMM_OK;
1001 break;
1002 }
f3ed775e 1003 case LTTNG_KERNEL_LIST_EVENTS:
2ef84c95
DG
1004 {
1005 char *event_list;
f3ed775e
DG
1006 ssize_t size = 0;
1007
1008 DBG("Listing kernel events");
2ef84c95
DG
1009
1010 size = kernel_list_events(kernel_tracer_fd, &event_list);
1011 if (size < 0) {
1012 ret = LTTCOMM_KERN_LIST_FAIL;
1013 goto error;
1014 }
1015
1016 /*
1017 * Setup lttng message with payload size set to the event list size in
1018 * bytes and then copy list into the llm payload.
1019 */
1020 ret = setup_lttng_msg(cmd_ctx, size);
1021 if (ret < 0) {
1022 goto setup_error;
1023 }
1024
1025 /* Copy event list into message payload */
1026 memcpy(cmd_ctx->llm->payload, event_list, size);
1027
1028 free(event_list);
1029
1030 ret = LTTCOMM_OK;
1031 break;
1032 }
f3ed775e 1033 case LTTNG_START_TRACE:
8c0faa1d
DG
1034 {
1035 struct ltt_kernel_channel *chan;
f3ed775e 1036
8c0faa1d
DG
1037 /* Setup lttng message with no payload */
1038 ret = setup_lttng_msg(cmd_ctx, 0);
1039 if (ret < 0) {
1040 goto setup_error;
1041 }
1042
f3ed775e
DG
1043 /* Kernel tracing */
1044 if (cmd_ctx->session->kernel_session != NULL) {
1045 if (cmd_ctx->session->kernel_session->metadata == NULL) {
1046 DBG("Open kernel metadata");
1047 ret = kernel_open_metadata(cmd_ctx->session->kernel_session);
1048 if (ret < 0) {
1049 ret = LTTCOMM_KERN_META_FAIL;
1050 goto error;
1051 }
1052 }
8c0faa1d 1053
f3ed775e
DG
1054 if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) {
1055 DBG("Opening kernel metadata stream");
1056 if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) {
1057 ret = kernel_open_metadata_stream(cmd_ctx->session->kernel_session);
1058 if (ret < 0) {
1059 ERR("Kernel create metadata stream failed");
1060 ret = LTTCOMM_KERN_STREAM_FAIL;
1061 goto error;
1062 }
1063 }
1064 }
8c0faa1d 1065
f3ed775e
DG
1066 /* For each channel */
1067 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
1068 if (chan->stream_count == 0) {
1069 ret = kernel_open_channel_stream(chan);
1070 if (ret < 0) {
1071 ERR("Kernel create channel stream failed");
1072 ret = LTTCOMM_KERN_STREAM_FAIL;
1073 goto error;
1074 }
1075 /* Update the stream global counter */
1076 cmd_ctx->session->kernel_session->stream_count_global += ret;
1077 }
1078 }
1079
1080 DBG("Start kernel tracing");
1081 ret = kernel_start_session(cmd_ctx->session->kernel_session);
8c0faa1d 1082 if (ret < 0) {
f3ed775e
DG
1083 ERR("Kernel start session failed");
1084 ret = LTTCOMM_KERN_START_FAIL;
8c0faa1d
DG
1085 goto error;
1086 }
8c0faa1d 1087
f3ed775e
DG
1088 ret = start_kernel_trace(cmd_ctx->session->kernel_session);
1089 if (ret < 0) {
1090 ret = LTTCOMM_KERN_START_FAIL;
8c0faa1d
DG
1091 goto error;
1092 }
8c0faa1d 1093
f3ed775e
DG
1094 /* Quiescent wait after starting trace */
1095 kernel_wait_quiescent(kernel_tracer_fd);
8c0faa1d
DG
1096 }
1097
f3ed775e 1098 /* TODO: Start all UST traces */
8c0faa1d
DG
1099
1100 ret = LTTCOMM_OK;
1101 break;
1102 }
f3ed775e 1103 case LTTNG_STOP_TRACE:
8c0faa1d 1104 {
f3ed775e 1105 struct ltt_kernel_channel *chan;
8c0faa1d
DG
1106 /* Setup lttng message with no payload */
1107 ret = setup_lttng_msg(cmd_ctx, 0);
1108 if (ret < 0) {
1109 goto setup_error;
1110 }
1111
f3ed775e
DG
1112 /* Kernel tracer */
1113 if (cmd_ctx->session->kernel_session != NULL) {
1114 DBG("Stop kernel tracing");
84291629 1115
f3ed775e
DG
1116 ret = kernel_metadata_flush_buffer(cmd_ctx->session->kernel_session->metadata_stream_fd);
1117 if (ret < 0) {
1118 ERR("Kernel metadata flush failed");
1119 }
8c0faa1d 1120
f3ed775e
DG
1121 cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
1122 ret = kernel_flush_buffer(chan);
1123 if (ret < 0) {
1124 ERR("Kernel flush buffer error");
1125 }
1126 }
1127
1128 ret = kernel_stop_session(cmd_ctx->session->kernel_session);
1129 if (ret < 0) {
1130 ERR("Kernel stop session failed");
1131 ret = LTTCOMM_KERN_STOP_FAIL;
1132 goto error;
1133 }
1134
1135 /* Quiescent wait after stopping trace */
1136 kernel_wait_quiescent(kernel_tracer_fd);
8c0faa1d
DG
1137 }
1138
f3ed775e 1139 /* TODO : User-space tracer */
8c0faa1d
DG
1140
1141 ret = LTTCOMM_OK;
1142 break;
1143 }
5e16da05
MD
1144 case LTTNG_CREATE_SESSION:
1145 {
5461b305
DG
1146 /* Setup lttng message with no payload */
1147 ret = setup_lttng_msg(cmd_ctx, 0);
1148 if (ret < 0) {
1149 goto setup_error;
1150 }
1151
f3ed775e 1152 ret = create_session(cmd_ctx->lsm->session_name, cmd_ctx->lsm->path);
5e16da05 1153 if (ret < 0) {
f3ed775e 1154 if (ret == -EEXIST) {
5e16da05
MD
1155 ret = LTTCOMM_EXIST_SESS;
1156 } else {
aaf97519 1157 ret = LTTCOMM_FATAL;
aaf97519 1158 }
5461b305 1159 goto error;
8028d920 1160 }
1657e9bb 1161
5461b305 1162 ret = LTTCOMM_OK;
5e16da05
MD
1163 break;
1164 }
1165 case LTTNG_DESTROY_SESSION:
1166 {
5461b305
DG
1167 /* Setup lttng message with no payload */
1168 ret = setup_lttng_msg(cmd_ctx, 0);
1169 if (ret < 0) {
1170 goto setup_error;
1171 }
1172
f3ed775e
DG
1173 /* Clean kernel session teardown */
1174 teardown_kernel_session(cmd_ctx->session);
1175
1176 ret = destroy_session(cmd_ctx->lsm->session_name);
5e16da05 1177 if (ret < 0) {
f3ed775e 1178 ret = LTTCOMM_FATAL;
5461b305 1179 goto error;
5e16da05 1180 }
1657e9bb 1181
5461b305
DG
1182 ret = LTTCOMM_OK;
1183 break;
5e16da05 1184 }
f3ed775e 1185 /*
5e16da05
MD
1186 case LTTNG_LIST_TRACES:
1187 {
5461b305 1188 unsigned int trace_count;
1657e9bb 1189
5461b305 1190 trace_count = get_trace_count_per_session(cmd_ctx->session);
5e16da05
MD
1191 if (trace_count == 0) {
1192 ret = LTTCOMM_NO_TRACE;
5461b305 1193 goto error;
1657e9bb 1194 }
df0da139 1195
5461b305
DG
1196 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count);
1197 if (ret < 0) {
1198 goto setup_error;
df0da139 1199 }
ca95a216 1200
5461b305
DG
1201 get_traces_per_session(cmd_ctx->session,
1202 (struct lttng_trace *)(cmd_ctx->llm->payload));
1203
1204 ret = LTTCOMM_OK;
5e16da05
MD
1205 break;
1206 }
f3ed775e
DG
1207 */
1208 /*
5e16da05
MD
1209 case UST_CREATE_TRACE:
1210 {
5461b305 1211 ret = setup_lttng_msg(cmd_ctx, 0);
5e16da05 1212 if (ret < 0) {
5461b305 1213 goto setup_error;
fac6795d 1214 }
ce3d728c 1215
5461b305
DG
1216 ret = ust_create_trace(cmd_ctx);
1217 if (ret < 0) {
f3ed775e 1218 goto error;
5461b305
DG
1219 }
1220 break;
5e16da05 1221 }
f3ed775e
DG
1222 */
1223 case LTTNG_LIST_TRACEABLE_APPS:
5e16da05 1224 {
5461b305
DG
1225 unsigned int app_count;
1226
1227 app_count = get_app_count();
1228 DBG("Traceable application count : %d", app_count);
5e16da05
MD
1229 if (app_count == 0) {
1230 ret = LTTCOMM_NO_APPS;
5461b305 1231 goto error;
ce3d728c 1232 }
520ff687 1233
5461b305
DG
1234 ret = setup_lttng_msg(cmd_ctx, sizeof(pid_t) * app_count);
1235 if (ret < 0) {
1236 goto setup_error;
520ff687 1237 }
57167058 1238
5461b305 1239 get_app_list_pids((pid_t *)(cmd_ctx->llm->payload));
5e16da05 1240
5461b305 1241 ret = LTTCOMM_OK;
5e16da05
MD
1242 break;
1243 }
f3ed775e 1244 /*
5e16da05
MD
1245 case UST_START_TRACE:
1246 {
5461b305
DG
1247 ret = setup_lttng_msg(cmd_ctx, 0);
1248 if (ret < 0) {
1249 goto setup_error;
1250 }
ca95a216 1251
5461b305
DG
1252 ret = ust_start_trace(cmd_ctx);
1253 if (ret < 0) {
1254 goto setup_error;
1255 }
1256 break;
5e16da05
MD
1257 }
1258 case UST_STOP_TRACE:
1259 {
5461b305
DG
1260 ret = setup_lttng_msg(cmd_ctx, 0);
1261 if (ret < 0) {
1262 goto setup_error;
1263 }
ca95a216 1264
5461b305
DG
1265 ret = ust_stop_trace(cmd_ctx);
1266 if (ret < 0) {
1267 goto setup_error;
1268 }
1269 break;
5e16da05 1270 }
f3ed775e 1271 */
5e16da05
MD
1272 case LTTNG_LIST_SESSIONS:
1273 {
5461b305
DG
1274 unsigned int session_count;
1275
1276 session_count = get_session_count();
5e16da05 1277 if (session_count == 0) {
f3ed775e 1278 ret = LTTCOMM_NO_SESSION;
5461b305 1279 goto error;
57167058 1280 }
5e16da05 1281
5461b305
DG
1282 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count);
1283 if (ret < 0) {
1284 goto setup_error;
e065084a 1285 }
5e16da05 1286
5461b305 1287 get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload));
5e16da05 1288
5461b305 1289 ret = LTTCOMM_OK;
5e16da05
MD
1290 break;
1291 }
1292 default:
1293 /* Undefined command */
5461b305
DG
1294 ret = setup_lttng_msg(cmd_ctx, 0);
1295 if (ret < 0) {
1296 goto setup_error;
1297 }
1298
5e16da05 1299 ret = LTTCOMM_UND;
5461b305 1300 break;
fac6795d
DG
1301 }
1302
5461b305
DG
1303 /* Set return code */
1304 cmd_ctx->llm->ret_code = ret;
ca95a216 1305
e065084a
DG
1306 return ret;
1307
5461b305 1308error:
5461b305
DG
1309 if (cmd_ctx->llm == NULL) {
1310 DBG("Missing llm structure. Allocating one.");
894be886 1311 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
5461b305
DG
1312 goto setup_error;
1313 }
1314 }
e065084a 1315 /* Notify client of error */
5461b305 1316 cmd_ctx->llm->ret_code = ret;
e065084a 1317
5461b305 1318setup_error:
8028d920 1319 return ret;
fac6795d
DG
1320}
1321
1d4b027a
DG
1322/*
1323 * thread_manage_clients
1324 *
1325 * This thread manage all clients request using the unix
1326 * client socket for communication.
1327 */
1328static void *thread_manage_clients(void *data)
1329{
1330 int sock, ret;
1331 struct command_ctx *cmd_ctx;
1332
1333 DBG("[thread] Manage client started");
1334
1335 ret = lttcomm_listen_unix_sock(client_sock);
1336 if (ret < 0) {
1337 goto error;
1338 }
1339
1340 /* Notify parent pid that we are ready
1341 * to accept command for client side.
1342 */
1343 if (opt_sig_parent) {
1344 kill(ppid, SIGCHLD);
1345 }
1346
1347 while (1) {
1348 /* Blocking call, waiting for transmission */
1349 DBG("Accepting client command ...");
1350 sock = lttcomm_accept_unix_sock(client_sock);
1351 if (sock < 0) {
1352 goto error;
1353 }
1354
1355 /* Allocate context command to process the client request */
1356 cmd_ctx = malloc(sizeof(struct command_ctx));
1357
1358 /* Allocate data buffer for reception */
1359 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
1360 cmd_ctx->llm = NULL;
1361 cmd_ctx->session = NULL;
1362
1363 /*
1364 * Data is received from the lttng client. The struct
1365 * lttcomm_session_msg (lsm) contains the command and data request of
1366 * the client.
1367 */
1368 DBG("Receiving data from client ...");
1369 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
1370 if (ret <= 0) {
1371 continue;
1372 }
1373
f7776ea7
DG
1374 // TODO: Validate cmd_ctx including sanity check for security purpose.
1375
1d4b027a
DG
1376 /*
1377 * This function dispatch the work to the kernel or userspace tracer
1378 * libs and fill the lttcomm_lttng_msg data structure of all the needed
1379 * informations for the client. The command context struct contains
1380 * everything this function may needs.
1381 */
1382 ret = process_client_msg(cmd_ctx);
1383 if (ret < 0) {
1384 /* TODO: Inform client somehow of the fatal error. At this point,
1385 * ret < 0 means that a malloc failed (ENOMEM). */
1386 /* Error detected but still accept command */
1387 clean_command_ctx(cmd_ctx);
1388 continue;
1389 }
1390
1391 DBG("Sending response (size: %d, retcode: %d)",
1392 cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
1393 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
1394 if (ret < 0) {
1395 ERR("Failed to send data back to client");
1396 }
1397
1398 clean_command_ctx(cmd_ctx);
d6e4fca4
DG
1399
1400 /* End of transmission */
1401 close(sock);
1d4b027a
DG
1402 }
1403
1404error:
1405 return NULL;
1406}
1407
1408
fac6795d
DG
1409/*
1410 * usage function on stderr
1411 */
1412static void usage(void)
1413{
b716ce68 1414 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
d6f42150
DG
1415 fprintf(stderr, " -h, --help Display this usage.\n");
1416 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
1417 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
1418 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
1419 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
1420 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
1421 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
1422 fprintf(stderr, " -V, --version Show version number.\n");
1423 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
1424 fprintf(stderr, " -q, --quiet No output at all.\n");
1425 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
fac6795d
DG
1426}
1427
1428/*
1429 * daemon argument parsing
1430 */
1431static int parse_args(int argc, char **argv)
1432{
1433 int c;
1434
1435 static struct option long_options[] = {
1436 { "client-sock", 1, 0, 'c' },
1437 { "apps-sock", 1, 0, 'a' },
d6f42150
DG
1438 { "kconsumerd-cmd-sock", 1, 0, 0 },
1439 { "kconsumerd-err-sock", 1, 0, 0 },
fac6795d 1440 { "daemonize", 0, 0, 'd' },
5b8719f5 1441 { "sig-parent", 0, 0, 'S' },
fac6795d
DG
1442 { "help", 0, 0, 'h' },
1443 { "group", 1, 0, 'g' },
1444 { "version", 0, 0, 'V' },
75462a81 1445 { "quiet", 0, 0, 'q' },
3f9947db 1446 { "verbose", 0, 0, 'v' },
fac6795d
DG
1447 { NULL, 0, 0, 0 }
1448 };
1449
1450 while (1) {
1451 int option_index = 0;
d6f42150 1452 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:E:C:", long_options, &option_index);
fac6795d
DG
1453 if (c == -1) {
1454 break;
1455 }
1456
1457 switch (c) {
1458 case 0:
1459 fprintf(stderr, "option %s", long_options[option_index].name);
1460 if (optarg) {
1461 fprintf(stderr, " with arg %s\n", optarg);
1462 }
1463 break;
b716ce68 1464 case 'c':
fac6795d
DG
1465 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
1466 break;
1467 case 'a':
1468 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
1469 break;
1470 case 'd':
1471 opt_daemon = 1;
1472 break;
1473 case 'g':
1474 opt_tracing_group = strdup(optarg);
1475 break;
1476 case 'h':
1477 usage();
1478 exit(EXIT_FAILURE);
1479 case 'V':
1480 fprintf(stdout, "%s\n", VERSION);
1481 exit(EXIT_SUCCESS);
5b8719f5
DG
1482 case 'S':
1483 opt_sig_parent = 1;
1484 break;
d6f42150
DG
1485 case 'E':
1486 snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, "%s", optarg);
1487 break;
1488 case 'C':
1489 snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, "%s", optarg);
1490 break;
75462a81
DG
1491 case 'q':
1492 opt_quiet = 1;
1493 break;
3f9947db
DG
1494 case 'v':
1495 opt_verbose = 1;
1496 break;
fac6795d
DG
1497 default:
1498 /* Unknown option or other error.
1499 * Error is printed by getopt, just return */
1500 return -1;
1501 }
1502 }
1503
1504 return 0;
1505}
1506
1507/*
1508 * init_daemon_socket
1509 *
1510 * Creates the two needed socket by the daemon.
d6f42150
DG
1511 * apps_sock - The communication socket for all UST apps.
1512 * client_sock - The communication of the cli tool (lttng).
fac6795d
DG
1513 */
1514static int init_daemon_socket()
1515{
1516 int ret = 0;
1517 mode_t old_umask;
1518
1519 old_umask = umask(0);
1520
1521 /* Create client tool unix socket */
d6f42150
DG
1522 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
1523 if (client_sock < 0) {
1524 ERR("Create unix sock failed: %s", client_unix_sock_path);
fac6795d
DG
1525 ret = -1;
1526 goto end;
1527 }
1528
1529 /* File permission MUST be 660 */
1530 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1531 if (ret < 0) {
d6f42150 1532 ERR("Set file permissions failed: %s", client_unix_sock_path);
fac6795d
DG
1533 perror("chmod");
1534 goto end;
1535 }
1536
1537 /* Create the application unix socket */
d6f42150
DG
1538 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
1539 if (apps_sock < 0) {
1540 ERR("Create unix sock failed: %s", apps_unix_sock_path);
fac6795d
DG
1541 ret = -1;
1542 goto end;
1543 }
1544
d6f42150 1545 /* File permission MUST be 666 */
fac6795d
DG
1546 ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
1547 if (ret < 0) {
d6f42150 1548 ERR("Set file permissions failed: %s", apps_unix_sock_path);
fac6795d
DG
1549 perror("chmod");
1550 goto end;
1551 }
1552
1553end:
1554 umask(old_umask);
1555 return ret;
1556}
1557
1558/*
1559 * check_existing_daemon
1560 *
1561 * Check if the global socket is available.
62bd06d8 1562 * If yes, error is returned.
fac6795d
DG
1563 */
1564static int check_existing_daemon()
1565{
1566 int ret;
1567
1568 ret = access(client_unix_sock_path, F_OK);
1569 if (ret == 0) {
1570 ret = access(apps_unix_sock_path, F_OK);
1571 }
1572
1573 return ret;
1574}
1575
1576/*
62bd06d8 1577 * get_home_dir
fac6795d 1578 *
62bd06d8
DG
1579 * Return pointer to home directory path using
1580 * the env variable HOME.
fac6795d 1581 *
62bd06d8 1582 * Default : /tmp
fac6795d
DG
1583 */
1584static const char *get_home_dir(void)
1585{
1586 const char *home_path;
1587
686204ab 1588 if ((home_path = (const char *) getenv("HOME")) == NULL) {
fac6795d
DG
1589 home_path = default_home_dir;
1590 }
1591
1592 return home_path;
1593}
1594
1595/*
d6f42150 1596 * set_permissions
fac6795d 1597 *
5e16da05
MD
1598 * Set the tracing group gid onto the client socket.
1599 *
1600 * Race window between mkdir and chown is OK because we are going from
1601 * less permissive (root.root) to more permissive (root.tracing).
fac6795d 1602 */
d6f42150 1603static int set_permissions(void)
fac6795d
DG
1604{
1605 int ret;
1606 struct group *grp;
1607
1608 /* Decide which group name to use */
1609 (opt_tracing_group != NULL) ?
1610 (grp = getgrnam(opt_tracing_group)) :
1611 (grp = getgrnam(default_tracing_group));
1612
1613 if (grp == NULL) {
75462a81 1614 ERR("Missing tracing group. Aborting execution.\n");
fac6795d
DG
1615 ret = -1;
1616 goto end;
1617 }
1618
d6f42150
DG
1619 /* Set lttng run dir */
1620 ret = chown(LTTNG_RUNDIR, 0, grp->gr_gid);
1621 if (ret < 0) {
1622 ERR("Unable to set group on " LTTNG_RUNDIR);
1623 perror("chown");
1624 }
1625
1626 /* lttng client socket path */
fac6795d
DG
1627 ret = chown(client_unix_sock_path, 0, grp->gr_gid);
1628 if (ret < 0) {
d6f42150
DG
1629 ERR("Unable to set group on %s", client_unix_sock_path);
1630 perror("chown");
1631 }
1632
1633 /* kconsumerd error socket path */
1634 ret = chown(kconsumerd_err_unix_sock_path, 0, grp->gr_gid);
1635 if (ret < 0) {
1636 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path);
fac6795d
DG
1637 perror("chown");
1638 }
1639
d6f42150 1640 DBG("All permissions are set");
e07ae692 1641
fac6795d
DG
1642end:
1643 return ret;
1644}
1645
d6f42150
DG
1646/*
1647 * create_lttng_rundir
1648 *
1649 * Create the lttng run directory needed for all
1650 * global sockets and pipe.
1651 */
1652static int create_lttng_rundir(void)
1653{
1654 int ret;
1655
1656 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
1657 if (ret < 0) {
b1f11e69
DG
1658 if (errno != EEXIST) {
1659 ERR("Unable to create " LTTNG_RUNDIR);
1660 goto error;
1661 } else {
1662 ret = 0;
1663 }
d6f42150
DG
1664 }
1665
1666error:
1667 return ret;
1668}
1669
1670/*
1671 * set_kconsumerd_sockets
1672 *
1673 * Setup sockets and directory needed by the kconsumerd
1674 * communication with the session daemon.
1675 */
1676static int set_kconsumerd_sockets(void)
1677{
1678 int ret;
1679
1680 if (strlen(kconsumerd_err_unix_sock_path) == 0) {
1681 snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, KCONSUMERD_ERR_SOCK_PATH);
1682 }
1683
1684 if (strlen(kconsumerd_cmd_unix_sock_path) == 0) {
1685 snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, KCONSUMERD_CMD_SOCK_PATH);
1686 }
1687
1688 ret = mkdir(KCONSUMERD_PATH, S_IRWXU | S_IRWXG);
1689 if (ret < 0) {
6beb2242
DG
1690 if (errno != EEXIST) {
1691 ERR("Failed to create " KCONSUMERD_PATH);
1692 goto error;
1693 }
1694 ret = 0;
d6f42150
DG
1695 }
1696
1697 /* Create the kconsumerd error unix socket */
1698 kconsumerd_err_sock = lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path);
1699 if (kconsumerd_err_sock < 0) {
1700 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path);
1701 ret = -1;
1702 goto error;
1703 }
1704
1705 /* File permission MUST be 660 */
1706 ret = chmod(kconsumerd_err_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1707 if (ret < 0) {
1708 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path);
1709 perror("chmod");
1710 goto error;
1711 }
1712
1713error:
1714 return ret;
1715}
1716
fac6795d 1717/*
62bd06d8 1718 * sighandler
fac6795d 1719 *
62bd06d8 1720 * Signal handler for the daemon
fac6795d
DG
1721 */
1722static void sighandler(int sig)
1723{
1724 switch (sig) {
1725 case SIGPIPE:
e07ae692 1726 DBG("SIGPIPE catched");
87378cf5 1727 return;
fac6795d 1728 case SIGINT:
e07ae692
DG
1729 DBG("SIGINT catched");
1730 cleanup();
1731 break;
fac6795d 1732 case SIGTERM:
e07ae692 1733 DBG("SIGTERM catched");
fac6795d 1734 cleanup();
686204ab 1735 break;
fac6795d
DG
1736 default:
1737 break;
1738 }
1739
1740 exit(EXIT_SUCCESS);
1741}
1742
1743/*
1d4b027a 1744 * set_signal_handler
fac6795d 1745 *
1d4b027a
DG
1746 * Setup signal handler for :
1747 * SIGINT, SIGTERM, SIGPIPE
fac6795d 1748 */
1d4b027a 1749static int set_signal_handler(void)
fac6795d 1750{
1d4b027a
DG
1751 int ret = 0;
1752 struct sigaction sa;
1753 sigset_t sigset;
fac6795d 1754
1d4b027a
DG
1755 if ((ret = sigemptyset(&sigset)) < 0) {
1756 perror("sigemptyset");
1757 return ret;
1758 }
d6f42150 1759
1d4b027a
DG
1760 sa.sa_handler = sighandler;
1761 sa.sa_mask = sigset;
1762 sa.sa_flags = 0;
1763 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
1764 perror("sigaction");
1765 return ret;
d6f42150
DG
1766 }
1767
1d4b027a
DG
1768 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
1769 perror("sigaction");
1770 return ret;
d6f42150 1771 }
aaf26714 1772
1d4b027a
DG
1773 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
1774 perror("sigaction");
1775 return ret;
8c0faa1d
DG
1776 }
1777
1d4b027a
DG
1778 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
1779
1780 return ret;
fac6795d
DG
1781}
1782
f3ed775e
DG
1783/*
1784 * set_ulimit
1785 *
1786 * Set open files limit to unlimited. This daemon can open a large number of
1787 * file descriptors in order to consumer multiple kernel traces.
1788 */
1789static void set_ulimit(void)
1790{
1791 int ret;
1792 struct rlimit lim;
1793
1794 lim.rlim_cur = 65535;
1795 lim.rlim_max = 65535;
1796
1797 ret = setrlimit(RLIMIT_NOFILE, &lim);
1798 if (ret < 0) {
1799 perror("failed to set open files limit");
1800 }
1801}
1802
fac6795d
DG
1803/*
1804 * main
1805 */
1806int main(int argc, char **argv)
1807{
fac6795d
DG
1808 int ret = 0;
1809 void *status;
fac6795d
DG
1810
1811 /* Parse arguments */
1812 progname = argv[0];
1813 if ((ret = parse_args(argc, argv) < 0)) {
1814 goto error;
1815 }
1816
1817 /* Daemonize */
1818 if (opt_daemon) {
53094c05
DG
1819 ret = daemon(0, 0);
1820 if (ret < 0) {
1821 perror("daemon");
1822 goto error;
1823 }
fac6795d
DG
1824 }
1825
1826 /* Check if daemon is UID = 0 */
1827 is_root = !getuid();
1828
1829 /* Set all sockets path */
1830 if (is_root) {
d6f42150
DG
1831 ret = create_lttng_rundir();
1832 if (ret < 0) {
1833 goto error;
1834 }
1835
fac6795d 1836 if (strlen(apps_unix_sock_path) == 0) {
d6f42150
DG
1837 snprintf(apps_unix_sock_path, PATH_MAX,
1838 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
fac6795d
DG
1839 }
1840
1841 if (strlen(client_unix_sock_path) == 0) {
d6f42150
DG
1842 snprintf(client_unix_sock_path, PATH_MAX,
1843 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
1844 }
1845
1846 ret = set_kconsumerd_sockets();
1847 if (ret < 0) {
1848 goto error;
fac6795d 1849 }
20fe2104
DG
1850
1851 /* Setup kernel tracer */
1852 init_kernel_tracer();
f3ed775e
DG
1853
1854 /* Set ulimit for open files */
1855 set_ulimit();
fac6795d
DG
1856 } else {
1857 if (strlen(apps_unix_sock_path) == 0) {
d6f42150
DG
1858 snprintf(apps_unix_sock_path, PATH_MAX,
1859 DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir());
fac6795d
DG
1860 }
1861
1862 /* Set the cli tool unix socket path */
1863 if (strlen(client_unix_sock_path) == 0) {
d6f42150
DG
1864 snprintf(client_unix_sock_path, PATH_MAX,
1865 DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir());
fac6795d
DG
1866 }
1867 }
1868
847177cd
DG
1869 DBG("Client socket path %s", client_unix_sock_path);
1870 DBG("Application socket path %s", apps_unix_sock_path);
1871
fac6795d
DG
1872 /* See if daemon already exist. If any of the two
1873 * socket needed by the daemon are present, this test fails
1874 */
1875 if ((ret = check_existing_daemon()) == 0) {
75462a81 1876 ERR("Already running daemon.\n");
ab118b20 1877 /* We do not goto error because we must not
d6f42150 1878 * cleanup() because a daemon is already running.
ab118b20 1879 */
5e16da05 1880 exit(EXIT_FAILURE);
fac6795d
DG
1881 }
1882
1883 if (set_signal_handler() < 0) {
1884 goto error;
1885 }
1886
d6f42150 1887 /* Setup the needed unix socket */
fac6795d
DG
1888 if (init_daemon_socket() < 0) {
1889 goto error;
1890 }
1891
1892 /* Set credentials to socket */
d6f42150 1893 if (is_root && (set_permissions() < 0)) {
fac6795d
DG
1894 goto error;
1895 }
1896
5b8719f5
DG
1897 /* Get parent pid if -S, --sig-parent is specified. */
1898 if (opt_sig_parent) {
1899 ppid = getppid();
1900 }
1901
fac6795d
DG
1902 while (1) {
1903 /* Create thread to manage the client socket */
1d4b027a 1904 ret = pthread_create(&client_thread, NULL, thread_manage_clients, (void *) NULL);
fac6795d
DG
1905 if (ret != 0) {
1906 perror("pthread_create");
1907 goto error;
1908 }
1909
1910 /* Create thread to manage application socket */
1d4b027a 1911 ret = pthread_create(&apps_thread, NULL, thread_manage_apps, (void *) NULL);
fac6795d
DG
1912 if (ret != 0) {
1913 perror("pthread_create");
1914 goto error;
1915 }
1916
1d4b027a
DG
1917 ret = pthread_join(client_thread, &status);
1918 if (ret != 0) {
1919 perror("pthread_join");
1920 goto error;
fac6795d
DG
1921 }
1922 }
1923
1924 cleanup();
5e16da05 1925 exit(EXIT_SUCCESS);
fac6795d
DG
1926
1927error:
1928 cleanup();
5e16da05 1929 exit(EXIT_FAILURE);
fac6795d 1930}
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