Empty import of libkernelctl
[lttng-tools.git] / ltt-sessiond / main.c
CommitLineData
826d496d
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1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
fac6795d
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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>
25#include <signal.h>
26#include <stdio.h>
27#include <stdlib.h>
28#include <string.h>
29#include <sys/ipc.h>
30#include <sys/shm.h>
31#include <sys/socket.h>
32#include <sys/stat.h>
33#include <sys/types.h>
34#include <unistd.h>
35
36#include <urcu/list.h> /* URCU list library (-lurcu) */
37#include <ust/ustctl.h> /* UST control lib (-lust) */
ca95a216 38#include <lttng/liblttngctl.h>
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39
40#include "liblttsessiondcomm.h"
41#include "ltt-sessiond.h"
75462a81 42#include "lttngerr.h"
5b74c7b1 43#include "session.h"
fda89c9b 44#include "trace.h"
91d76f53 45#include "traceable-app.h"
fac6795d 46
75462a81 47/* Const values */
686204ab
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48const char default_home_dir[] = DEFAULT_HOME_DIR;
49const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
50const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
51const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
52
fac6795d 53/* Static functions */
fac6795d 54static int check_existing_daemon(void);
1fd70b72 55static int connect_app(pid_t pid);
fac6795d 56static int init_daemon_socket(void);
62bd06d8 57static int notify_apps(const char* name);
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58static int process_client_msg(int sock, struct lttcomm_session_msg*);
59static int send_unix_sock(int sock, void *buf, size_t len);
62bd06d8
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60static int set_signal_handler(void);
61static int set_socket_perms(void);
aaf97519 62static int setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_msg *llm);
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63static void cleanup(void);
64static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm);
65static void sighandler(int sig);
fac6795d 66
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67static void *thread_manage_clients(void *data);
68static void *thread_manage_apps(void *data);
fac6795d 69
fac6795d 70/* Variables */
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71int opt_verbose;
72int opt_quiet;
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73const char *progname;
74const char *opt_tracing_group;
5b8719f5 75static int opt_sig_parent;
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76static int opt_daemon;
77static int is_root; /* Set to 1 if the daemon is running as root */
5b8719f5 78static pid_t ppid;
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79
80static char apps_unix_sock_path[PATH_MAX]; /* Global application Unix socket path */
81static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */
82
83static int client_socket;
84static int apps_socket;
85
86static struct ltt_session *current_session;
e065084a 87
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88/*
89 * thread_manage_apps
90 *
91 * This thread manage the application socket communication
92 */
93static void *thread_manage_apps(void *data)
94{
95 int sock, ret;
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96
97 /* TODO: Something more elegant is needed but fine for now */
686204ab 98 struct {
fac6795d 99 int reg; /* 1:register, 0:unregister */
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100 pid_t pid;
101 uid_t uid;
102 } reg_msg;
fac6795d 103
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104 DBG("[thread] Manage apps started");
105
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106 /* Notify all applications to register */
107 notify_apps(default_global_apps_pipe);
108
109 ret = lttcomm_listen_unix_sock(apps_socket);
110 if (ret < 0) {
111 goto error;
112 }
113
114 while (1) {
115 /* Blocking call, waiting for transmission */
116 sock = lttcomm_accept_unix_sock(apps_socket);
117 if (sock < 0) {
118 goto error;
119 }
120
121 /* Basic recv here to handle the very simple data
122 * that the libust send to register (reg_msg).
123 */
124 ret = recv(sock, &reg_msg, sizeof(reg_msg), 0);
125 if (ret < 0) {
126 perror("recv");
127 continue;
128 }
129
130 /* Add application to the global traceable list */
131 if (reg_msg.reg == 1) {
132 /* Registering */
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133 ret = register_traceable_app(reg_msg.pid, reg_msg.uid);
134 if (ret < 0) {
135 /* register_traceable_app only return an error with
136 * ENOMEM. At this point, we better stop everything.
137 */
138 goto error;
139 }
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140 } else {
141 /* Unregistering */
91d76f53 142 unregister_traceable_app(reg_msg.pid);
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143 }
144 }
145
146error:
147
148 return NULL;
149}
150
151/*
152 * thread_manage_clients
153 *
154 * This thread manage all clients request using the unix
155 * client socket for communication.
156 */
157static void *thread_manage_clients(void *data)
158{
159 int sock, ret;
160 struct lttcomm_session_msg lsm;
fac6795d 161
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162 DBG("[thread] Manage client started");
163
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164 ret = lttcomm_listen_unix_sock(client_socket);
165 if (ret < 0) {
166 goto error;
167 }
168
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169 /* Notify parent pid that we are ready
170 * to accept command for client side.
171 */
172 if (opt_sig_parent) {
173 kill(ppid, SIGCHLD);
174 }
175
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176 while (1) {
177 /* Blocking call, waiting for transmission */
178 sock = lttcomm_accept_unix_sock(client_socket);
179 if (sock < 0) {
180 goto error;
181 }
182
183 /*
184 * Data is received from the lttng client. The struct
185 * lttcomm_session_msg (lsm) contains the command and data
186 * request of the client.
187 */
188 ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm));
87378cf5 189 if (ret <= 0) {
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190 continue;
191 }
192
193 /* This function dispatch the work to the LTTng or UST libs
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194 * and then sends back the response to the client. This is needed
195 * because there might be more then one lttcomm_lttng_msg to
196 * send out so process_client_msg do both jobs.
fac6795d 197 */
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198 ret = process_client_msg(sock, &lsm);
199 if (ret < 0) {
200 /* Error detected but still accept command */
201 continue;
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202 }
203 }
204
205error:
206 return NULL;
207}
208
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209/*
210 * send_unix_sock
211 *
212 * Send data on a unix socket using the liblttsessiondcomm API.
213 *
214 * Return lttcomm error code.
215 */
216static int send_unix_sock(int sock, void *buf, size_t len)
217{
218 /* Check valid length */
219 if (len <= 0) {
220 return -1;
221 }
222
223 return lttcomm_send_unix_sock(sock, buf, len);
224}
225
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226/*
227 * connect_app
228 *
229 * Return a socket connected to the libust communication socket
230 * of the application identified by the pid.
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231 *
232 * If the pid is not found in the traceable list,
233 * return -1 to indicate error.
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234 */
235static int connect_app(pid_t pid)
236{
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237 int sock;
238 struct ltt_traceable_app *lta;
379473d2 239
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240 DBG("Connect to application pid %d", pid);
241
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242 lta = find_app_by_pid(pid);
243 if (lta == NULL) {
244 /* App not found */
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245 return -1;
246 }
fac6795d 247
91d76f53 248 sock = ustctl_connect_pid(lta->pid);
fac6795d 249 if (sock < 0) {
75462a81 250 ERR("Fail connecting to the PID %d\n", pid);
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251 }
252
253 return sock;
254}
255
256/*
257 * notify_apps
258 *
259 * Notify apps by writing 42 to a named pipe using name.
260 * Every applications waiting for a ltt-sessiond will be notified
261 * and re-register automatically to the session daemon.
262 *
263 * Return open or write error value.
264 */
265static int notify_apps(const char *name)
266{
267 int fd;
268 int ret = -1;
269
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270 DBG("Notify the global application pipe");
271
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272 /* Try opening the global pipe */
273 fd = open(name, O_WRONLY);
274 if (fd < 0) {
275 goto error;
276 }
277
278 /* Notify by writing on the pipe */
279 ret = write(fd, "42", 2);
280 if (ret < 0) {
281 perror("write");
282 }
283
284error:
285 return ret;
286}
287
379473d2
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288/*
289 * ust_create_trace
290 *
291 * Create an userspace trace using pid.
292 * This trace is then appended to the current session
293 * ust trace list.
294 */
295static int ust_create_trace(pid_t pid)
296{
297 int sock, ret;
298 struct ltt_ust_trace *trace;
299
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300 DBG("Creating trace for pid %d", pid);
301
379473d2
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302 trace = malloc(sizeof(struct ltt_ust_trace));
303 if (trace == NULL) {
304 perror("malloc");
305 ret = -1;
306 goto error;
307 }
308
309 /* Init */
310 trace->pid = pid;
311 trace->shmid = 0;
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312 /* NOTE: to be removed. Trace name will no longer be
313 * required for LTTng userspace tracer. For now, we set it
314 * to 'auto' for API compliance.
315 */
316 snprintf(trace->name, 5, "auto");
379473d2
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317
318 /* Connect to app using ustctl API */
319 sock = connect_app(pid);
320 if (sock < 0) {
321 ret = LTTCOMM_NO_TRACEABLE;
322 goto error;
323 }
324
1657e9bb 325 ret = ustctl_create_trace(sock, trace->name);
379473d2
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326 if (ret < 0) {
327 ret = LTTCOMM_CREATE_FAIL;
328 goto error;
329 }
330
331 /* Check if current session is valid */
332 if (current_session) {
333 cds_list_add(&trace->list, &current_session->ust_traces);
1657e9bb 334 current_session->ust_trace_count++;
379473d2
DG
335 }
336
337error:
338 return ret;
339}
340
ce3d728c
DG
341/*
342 * ust_start_trace
343 *
344 * Start a trace. This trace, identified by the pid, must be
345 * in the current session ust_traces list.
346 */
347static int ust_start_trace(pid_t pid)
348{
349 int sock, ret;
350 struct ltt_ust_trace *trace;
351
352 DBG("Starting trace for pid %d", pid);
353
354 trace = find_session_ust_trace_by_pid(current_session, pid);
355 if (trace == NULL) {
356 ret = LTTCOMM_NO_TRACE;
357 goto error;
358 }
359
360 /* Connect to app using ustctl API */
361 sock = connect_app(pid);
362 if (sock < 0) {
363 ret = LTTCOMM_NO_TRACEABLE;
364 goto error;
365 }
366
367 ret = ustctl_start_trace(sock, "auto");
368 if (ret < 0) {
369 ret = LTTCOMM_START_FAIL;
370 goto error;
371 }
372
373error:
374 return ret;
375}
376
520ff687
DG
377/*
378 * ust_stop_trace
379 *
380 * Stop a trace. This trace, identified by the pid, must be
381 * in the current session ust_traces list.
382 */
383static int ust_stop_trace(pid_t pid)
384{
385 int sock, ret;
386 struct ltt_ust_trace *trace;
387
388 DBG("Stopping trace for pid %d", pid);
389
390 trace = find_session_ust_trace_by_pid(current_session, pid);
391 if (trace == NULL) {
392 ret = LTTCOMM_NO_TRACE;
393 goto error;
394 }
395
396 /* Connect to app using ustctl API */
397 sock = connect_app(pid);
398 if (sock < 0) {
399 ret = LTTCOMM_NO_TRACEABLE;
400 goto error;
401 }
402
403 ret = ustctl_stop_trace(sock, trace->name);
404 if (ret < 0) {
405 ret = LTTCOMM_STOP_FAIL;
406 goto error;
407 }
408
409error:
410 return ret;
411}
412
e065084a
DG
413/*
414 * copy_common_data
415 *
416 * Copy common data between lttcomm_lttng_msg and lttcomm_session_msg
417 */
418static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm)
419{
420 llm->cmd_type = lsm->cmd_type;
421 llm->pid = lsm->pid;
aaf97519
DG
422
423 /* Manage uuid */
8028d920
DG
424 if (!uuid_is_null(lsm->session_id)) {
425 uuid_copy(llm->session_id, lsm->session_id);
e065084a 426 }
aaf97519
DG
427
428 strncpy(llm->trace_name, lsm->trace_name, strlen(llm->trace_name));
8028d920 429 llm->trace_name[strlen(llm->trace_name) - 1] = '\0';
e065084a
DG
430}
431
ca95a216
DG
432/*
433 * setup_data_buffer
434 *
435 * Setup the outgoing data buffer for the response
436 * data allocating the right amount of memory.
437 *
438 * Return total size of the buffer pointed by buf.
439 */
aaf97519 440static int setup_data_buffer(char **buf, size_t s_data, struct lttcomm_lttng_msg *llm)
ca95a216
DG
441{
442 int ret = 0;
ca95a216
DG
443 size_t buf_size;
444
445 buf_size = sizeof(struct lttcomm_lttng_msg) + s_data;
aaf97519
DG
446 *buf = malloc(buf_size);
447 if (*buf == NULL) {
ca95a216
DG
448 perror("malloc");
449 ret = -1;
450 goto error;
451 }
452
453 /* Setup lttcomm_lttng_msg data and copy
454 * it to the newly allocated buffer.
455 */
456 llm->size_payload = s_data;
aaf97519 457 memcpy(*buf, llm, sizeof(struct lttcomm_lttng_msg));
ca95a216
DG
458
459 return buf_size;
460
461error:
462 return ret;
463}
464
fac6795d
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465/*
466 * process_client_msg
467 *
468 * This takes the lttcomm_session_msg struct and process the command requested
e065084a
DG
469 * by the client. It then creates response(s) and send it back to the
470 * given socket (sock).
fac6795d 471 *
e065084a 472 * Return any error encountered or 0 for success.
fac6795d 473 */
e065084a 474static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
fac6795d 475{
e065084a 476 int ret;
ca95a216 477 int buf_size;
7e6e59cd 478 size_t header_size;
aaf97519
DG
479 char *send_buf = NULL;
480 struct lttcomm_lttng_msg llm;
fac6795d 481
e07ae692
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482 DBG("Processing client message");
483
fac6795d
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484 /* Copy common data to identify the response
485 * on the lttng client side.
486 */
e065084a 487 copy_common_data(&llm, lsm);
fac6795d 488
379473d2
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489 /* Check command that needs a session */
490 if (lsm->cmd_type != LTTNG_CREATE_SESSION &&
491 lsm->cmd_type != LTTNG_LIST_SESSIONS &&
492 lsm->cmd_type != UST_LIST_APPS)
493 {
494 current_session = find_session_by_uuid(lsm->session_id);
495 if (current_session == NULL) {
496 ret = LTTCOMM_SELECT_SESS;
497 goto end;
498 }
499 }
500
fac6795d 501 /* Default return code.
e065084a 502 * In our world, everything is OK... right? ;)
fac6795d 503 */
e065084a 504 llm.ret_code = LTTCOMM_OK;
fac6795d 505
7e6e59cd
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506 header_size = sizeof(struct lttcomm_lttng_msg);
507
fac6795d
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508 /* Process by command type */
509 switch (lsm->cmd_type) {
aaf97519
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510 case LTTNG_CREATE_SESSION:
511 {
8028d920 512 ret = create_session(lsm->session_name, &llm.session_id);
aaf97519 513 if (ret < 0) {
27673bb6
DG
514 if (ret == -1) {
515 ret = LTTCOMM_EXIST_SESS;
516 } else {
517 ret = LTTCOMM_FATAL;
518 }
8028d920 519 goto end;
aaf97519
DG
520 }
521
aaf97519
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522 buf_size = setup_data_buffer(&send_buf, 0, &llm);
523 if (buf_size < 0) {
524 ret = LTTCOMM_FATAL;
8028d920 525 goto end;
aaf97519
DG
526 }
527
aaf97519
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528 break;
529 }
8028d920
DG
530 case LTTNG_DESTROY_SESSION:
531 {
532 ret = destroy_session(&lsm->session_id);
533 if (ret < 0) {
534 ret = LTTCOMM_NO_SESS;
535 } else {
536 ret = LTTCOMM_OK;
537 }
538
539 /* No auxiliary data so only send the llm struct. */
540 goto end;
541 }
1657e9bb
DG
542 case LTTNG_LIST_TRACES:
543 {
544 unsigned int trace_count = get_trace_count_per_session(current_session);
545
546 if (trace_count == 0) {
547 ret = LTTCOMM_NO_TRACE;
548 goto end;
549 }
550
551 buf_size = setup_data_buffer(&send_buf,
552 sizeof(struct lttng_trace) * trace_count, &llm);
553 if (buf_size < 0) {
554 ret = LTTCOMM_FATAL;
555 goto end;
556 }
557
558 get_traces_per_session(current_session, (struct lttng_trace *)(send_buf + header_size));
559 break;
560 }
df0da139
DG
561 case UST_CREATE_TRACE:
562 {
379473d2 563 ret = ust_create_trace(lsm->pid);
df0da139 564 if (ret < 0) {
ce3d728c
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565 /* If -1 is returned from ust_create_trace, malloc
566 * failed so it's pretty much a fatal error.
567 */
568 ret = LTTCOMM_FATAL;
379473d2 569 goto end;
df0da139
DG
570 }
571
379473d2 572 /* No auxiliary data so only send the llm struct. */
df0da139
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573 goto end;
574 }
fac6795d
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575 case UST_LIST_APPS:
576 {
91d76f53 577 unsigned int app_count = get_app_count();
ca95a216 578 /* Stop right now if no apps */
91d76f53 579 if (app_count == 0) {
e065084a 580 ret = LTTCOMM_NO_APPS;
8028d920 581 goto end;
e065084a
DG
582 }
583
ca95a216
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584 /* Setup data buffer and details for transmission */
585 buf_size = setup_data_buffer(&send_buf,
91d76f53 586 sizeof(pid_t) * app_count, &llm);
ca95a216
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587 if (buf_size < 0) {
588 ret = LTTCOMM_FATAL;
8028d920 589 goto end;
ca95a216
DG
590 }
591
91d76f53 592 get_app_list_pids((pid_t *)(send_buf + header_size));
ca95a216 593
fac6795d
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594 break;
595 }
ce3d728c
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596 case UST_START_TRACE:
597 {
598 ret = ust_start_trace(lsm->pid);
599
600 /* No auxiliary data so only send the llm struct. */
601 goto end;
602 }
520ff687
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603 case UST_STOP_TRACE:
604 {
605 ret = ust_stop_trace(lsm->pid);
606
607 /* No auxiliary data so only send the llm struct. */
608 goto end;
609 }
57167058
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610 case LTTNG_LIST_SESSIONS:
611 {
5b74c7b1 612 unsigned int session_count = get_session_count();
ca95a216
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613 /* Stop right now if no session */
614 if (session_count == 0) {
57167058 615 ret = LTTCOMM_NO_SESS;
8028d920 616 goto end;
57167058
DG
617 }
618
ca95a216
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619 /* Setup data buffer and details for transmission */
620 buf_size = setup_data_buffer(&send_buf,
621 (sizeof(struct lttng_session) * session_count), &llm);
622 if (buf_size < 0) {
623 ret = LTTCOMM_FATAL;
8028d920 624 goto end;
ca95a216
DG
625 }
626
5b74c7b1 627 get_lttng_session((struct lttng_session *)(send_buf + header_size));
ca95a216 628
57167058
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629 break;
630 }
fac6795d 631 default:
e065084a 632 {
fac6795d 633 /* Undefined command */
e065084a 634 ret = LTTCOMM_UND;
8028d920 635 goto end;
e065084a 636 }
fac6795d
DG
637 }
638
1fd70b72
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639 ret = send_unix_sock(sock, send_buf, buf_size);
640
ca95a216
DG
641 if (send_buf != NULL) {
642 free(send_buf);
643 }
644
e065084a
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645 return ret;
646
8028d920 647end:
e065084a
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648 /* Notify client of error */
649 llm.ret_code = ret;
ca95a216 650 llm.size_payload = 0;
e065084a
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651 send_unix_sock(sock, (void*) &llm, sizeof(llm));
652
8028d920 653 return ret;
fac6795d
DG
654}
655
656/*
657 * usage function on stderr
658 */
659static void usage(void)
660{
b716ce68
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661 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
662 fprintf(stderr, " -h, --help Display this usage.\n");
663 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
664 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket.\n");
665 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
666 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
667 fprintf(stderr, " -V, --version Show version number.\n");
668 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
669 fprintf(stderr, " -q, --quiet No output at all.\n");
3f9947db 670 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
fac6795d
DG
671}
672
673/*
674 * daemon argument parsing
675 */
676static int parse_args(int argc, char **argv)
677{
678 int c;
679
680 static struct option long_options[] = {
681 { "client-sock", 1, 0, 'c' },
682 { "apps-sock", 1, 0, 'a' },
683 { "daemonize", 0, 0, 'd' },
5b8719f5 684 { "sig-parent", 0, 0, 'S' },
fac6795d
DG
685 { "help", 0, 0, 'h' },
686 { "group", 1, 0, 'g' },
687 { "version", 0, 0, 'V' },
75462a81 688 { "quiet", 0, 0, 'q' },
3f9947db 689 { "verbose", 0, 0, 'v' },
fac6795d
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690 { NULL, 0, 0, 0 }
691 };
692
693 while (1) {
694 int option_index = 0;
3f9947db 695 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:", long_options, &option_index);
fac6795d
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696 if (c == -1) {
697 break;
698 }
699
700 switch (c) {
701 case 0:
702 fprintf(stderr, "option %s", long_options[option_index].name);
703 if (optarg) {
704 fprintf(stderr, " with arg %s\n", optarg);
705 }
706 break;
b716ce68 707 case 'c':
fac6795d
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708 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
709 break;
710 case 'a':
711 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
712 break;
713 case 'd':
714 opt_daemon = 1;
715 break;
716 case 'g':
717 opt_tracing_group = strdup(optarg);
718 break;
719 case 'h':
720 usage();
721 exit(EXIT_FAILURE);
722 case 'V':
723 fprintf(stdout, "%s\n", VERSION);
724 exit(EXIT_SUCCESS);
5b8719f5
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725 case 'S':
726 opt_sig_parent = 1;
727 break;
75462a81
DG
728 case 'q':
729 opt_quiet = 1;
730 break;
3f9947db
DG
731 case 'v':
732 opt_verbose = 1;
733 break;
fac6795d
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734 default:
735 /* Unknown option or other error.
736 * Error is printed by getopt, just return */
737 return -1;
738 }
739 }
740
741 return 0;
742}
743
744/*
745 * init_daemon_socket
746 *
747 * Creates the two needed socket by the daemon.
62bd06d8
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748 * apps_socket - The communication socket for all UST apps.
749 * client_socket - The communication of the cli tool (lttng).
fac6795d
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750 */
751static int init_daemon_socket()
752{
753 int ret = 0;
754 mode_t old_umask;
755
756 old_umask = umask(0);
757
758 /* Create client tool unix socket */
759 client_socket = lttcomm_create_unix_sock(client_unix_sock_path);
760 if (client_socket < 0) {
761 ret = -1;
762 goto end;
763 }
764
765 /* File permission MUST be 660 */
766 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
767 if (ret < 0) {
768 perror("chmod");
769 goto end;
770 }
771
772 /* Create the application unix socket */
773 apps_socket = lttcomm_create_unix_sock(apps_unix_sock_path);
774 if (apps_socket < 0) {
775 ret = -1;
776 goto end;
777 }
778
779 /* File permission MUST be 660 */
780 ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
781 if (ret < 0) {
782 perror("chmod");
783 goto end;
784 }
785
786end:
787 umask(old_umask);
788 return ret;
789}
790
791/*
792 * check_existing_daemon
793 *
794 * Check if the global socket is available.
62bd06d8 795 * If yes, error is returned.
fac6795d
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796 */
797static int check_existing_daemon()
798{
799 int ret;
800
801 ret = access(client_unix_sock_path, F_OK);
802 if (ret == 0) {
803 ret = access(apps_unix_sock_path, F_OK);
804 }
805
806 return ret;
807}
808
809/*
62bd06d8 810 * get_home_dir
fac6795d 811 *
62bd06d8
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812 * Return pointer to home directory path using
813 * the env variable HOME.
fac6795d 814 *
62bd06d8 815 * Default : /tmp
fac6795d
DG
816 */
817static const char *get_home_dir(void)
818{
819 const char *home_path;
820
686204ab 821 if ((home_path = (const char *) getenv("HOME")) == NULL) {
fac6795d
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822 home_path = default_home_dir;
823 }
824
825 return home_path;
826}
827
828/*
829 * set_socket_perms
830 *
831 * Set the tracing group gid onto the client socket.
832 */
833static int set_socket_perms(void)
834{
835 int ret;
836 struct group *grp;
837
838 /* Decide which group name to use */
839 (opt_tracing_group != NULL) ?
840 (grp = getgrnam(opt_tracing_group)) :
841 (grp = getgrnam(default_tracing_group));
842
843 if (grp == NULL) {
75462a81 844 ERR("Missing tracing group. Aborting execution.\n");
fac6795d
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845 ret = -1;
846 goto end;
847 }
848
849 ret = chown(client_unix_sock_path, 0, grp->gr_gid);
850 if (ret < 0) {
851 perror("chown");
852 }
853
e07ae692
DG
854 DBG("Sockets permissions set");
855
fac6795d
DG
856end:
857 return ret;
858}
859
fac6795d 860/*
62bd06d8 861 * set_signal_handler
fac6795d 862 *
62bd06d8 863 * Setup signal handler for :
fac6795d
DG
864 * SIGINT, SIGTERM, SIGPIPE
865 */
866static int set_signal_handler(void)
867{
868 int ret = 0;
869 struct sigaction sa;
870 sigset_t sigset;
871
872 if ((ret = sigemptyset(&sigset)) < 0) {
873 perror("sigemptyset");
874 return ret;
875 }
876
877 sa.sa_handler = sighandler;
878 sa.sa_mask = sigset;
879 sa.sa_flags = 0;
880 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
881 perror("sigaction");
882 return ret;
883 }
884
885 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
886 perror("sigaction");
887 return ret;
888 }
889
890 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
891 perror("sigaction");
892 return ret;
893 }
894
e07ae692
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895 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
896
fac6795d
DG
897 return ret;
898}
899
900/**
62bd06d8 901 * sighandler
fac6795d 902 *
62bd06d8 903 * Signal handler for the daemon
fac6795d
DG
904 */
905static void sighandler(int sig)
906{
907 switch (sig) {
908 case SIGPIPE:
e07ae692 909 DBG("SIGPIPE catched");
87378cf5 910 return;
fac6795d 911 case SIGINT:
e07ae692
DG
912 DBG("SIGINT catched");
913 cleanup();
914 break;
fac6795d 915 case SIGTERM:
e07ae692 916 DBG("SIGTERM catched");
fac6795d 917 cleanup();
686204ab 918 break;
fac6795d
DG
919 default:
920 break;
921 }
922
923 exit(EXIT_SUCCESS);
924}
925
926/*
62bd06d8 927 * cleanup
fac6795d 928 *
62bd06d8 929 * Cleanup the daemon on exit
fac6795d
DG
930 */
931static void cleanup()
932{
e07ae692
DG
933 DBG("Cleaning up");
934
fac6795d 935 /* <fun> */
b716ce68
DG
936 MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
937 MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0);
fac6795d
DG
938 /* </fun> */
939
940 unlink(client_unix_sock_path);
941 unlink(apps_unix_sock_path);
942}
943
944/*
945 * main
946 */
947int main(int argc, char **argv)
948{
949 int i;
950 int ret = 0;
951 void *status;
952 pthread_t threads[2];
953
954 /* Parse arguments */
955 progname = argv[0];
956 if ((ret = parse_args(argc, argv) < 0)) {
957 goto error;
958 }
959
960 /* Daemonize */
961 if (opt_daemon) {
53094c05
DG
962 ret = daemon(0, 0);
963 if (ret < 0) {
964 perror("daemon");
965 goto error;
966 }
fac6795d
DG
967 }
968
969 /* Check if daemon is UID = 0 */
970 is_root = !getuid();
971
972 /* Set all sockets path */
973 if (is_root) {
974 if (strlen(apps_unix_sock_path) == 0) {
975 (snprintf(apps_unix_sock_path, PATH_MAX,
976 DEFAULT_GLOBAL_APPS_UNIX_SOCK));
977 }
978
979 if (strlen(client_unix_sock_path) == 0) {
980 (snprintf(client_unix_sock_path, PATH_MAX,
981 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK));
982 }
983 } else {
984 if (strlen(apps_unix_sock_path) == 0) {
985 (snprintf(apps_unix_sock_path, PATH_MAX,
986 DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir()));
987 }
988
989 /* Set the cli tool unix socket path */
990 if (strlen(client_unix_sock_path) == 0) {
991 (snprintf(client_unix_sock_path, PATH_MAX,
992 DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir()));
993 }
994 }
995
996 /* See if daemon already exist. If any of the two
997 * socket needed by the daemon are present, this test fails
998 */
999 if ((ret = check_existing_daemon()) == 0) {
75462a81 1000 ERR("Already running daemon.\n");
ab118b20
DG
1001 /* We do not goto error because we must not
1002 * cleanup() because a daemon is already working.
1003 */
1004 return EXIT_FAILURE;
fac6795d
DG
1005 }
1006
1007 if (set_signal_handler() < 0) {
1008 goto error;
1009 }
1010
1011 /* Setup the two needed unix socket */
1012 if (init_daemon_socket() < 0) {
1013 goto error;
1014 }
1015
1016 /* Set credentials to socket */
1017 if (is_root && (set_socket_perms() < 0)) {
1018 goto error;
1019 }
1020
5b8719f5
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1021 /* Get parent pid if -S, --sig-parent is specified. */
1022 if (opt_sig_parent) {
1023 ppid = getppid();
1024 }
1025
fac6795d
DG
1026 while (1) {
1027 /* Create thread to manage the client socket */
1028 ret = pthread_create(&threads[0], NULL, thread_manage_clients, (void *) NULL);
1029 if (ret != 0) {
1030 perror("pthread_create");
1031 goto error;
1032 }
1033
1034 /* Create thread to manage application socket */
1035 ret = pthread_create(&threads[1], NULL, thread_manage_apps, (void *) NULL);
1036 if (ret != 0) {
1037 perror("pthread_create");
1038 goto error;
1039 }
1040
1041 for (i = 0; i < 2; i++) {
1042 ret = pthread_join(threads[i], &status);
1043 if (ret != 0) {
1044 perror("pthread_join");
1045 goto error;
1046 }
1047 }
1048 }
1049
1050 cleanup();
1051 return 0;
1052
1053error:
1054 cleanup();
1055
1056 return EXIT_FAILURE;
1057}
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