Fix: error when listing sessions with no session
[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.c
1 /*
2 * lttng-ctl.c
3 *
4 * Linux Trace Toolkit Control Library
5 *
6 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
7 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
8 *
9 * This library is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU Lesser General Public License, version 2.1 only,
11 * as published by the Free Software Foundation.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this library; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #define _LGPL_SOURCE
24 #include <assert.h>
25 #include <grp.h>
26 #include <errno.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <unistd.h>
31
32 #include <common/common.h>
33 #include <common/compat/string.h>
34 #include <common/defaults.h>
35 #include <common/sessiond-comm/sessiond-comm.h>
36 #include <common/uri.h>
37 #include <common/utils.h>
38 #include <common/dynamic-buffer.h>
39 #include <lttng/lttng.h>
40 #include <lttng/health-internal.h>
41 #include <lttng/trigger/trigger-internal.h>
42 #include <lttng/endpoint.h>
43 #include <lttng/channel-internal.h>
44 #include <lttng/event-internal.h>
45 #include <lttng/userspace-probe-internal.h>
46 #include <lttng/session-internal.h>
47 #include <lttng/session-descriptor-internal.h>
48
49 #include "filter/filter-ast.h"
50 #include "filter/filter-parser.h"
51 #include "filter/filter-bytecode.h"
52 #include "filter/memstream.h"
53 #include "lttng-ctl-helper.h"
54
55 #ifdef DEBUG
56 static const int print_xml = 1;
57 #define dbg_printf(fmt, args...) \
58 printf("[debug liblttng-ctl] " fmt, ## args)
59 #else
60 static const int print_xml = 0;
61 #define dbg_printf(fmt, args...) \
62 do { \
63 /* do nothing but check printf format */ \
64 if (0) \
65 printf("[debug liblttnctl] " fmt, ## args); \
66 } while (0)
67 #endif
68
69
70 /* Socket to session daemon for communication */
71 static int sessiond_socket;
72 static char sessiond_sock_path[PATH_MAX];
73
74 /* Variables */
75 static char *tracing_group;
76 static int connected;
77
78 /* Global */
79
80 /*
81 * Those two variables are used by error.h to silent or control the verbosity of
82 * error message. They are global to the library so application linking with it
83 * are able to compile correctly and also control verbosity of the library.
84 */
85 int lttng_opt_quiet;
86 int lttng_opt_verbose;
87 int lttng_opt_mi;
88
89 /*
90 * Copy string from src to dst and enforce null terminated byte.
91 */
92 LTTNG_HIDDEN
93 void lttng_ctl_copy_string(char *dst, const char *src, size_t len)
94 {
95 if (src && dst) {
96 strncpy(dst, src, len);
97 /* Enforce the NULL terminated byte */
98 dst[len - 1] = '\0';
99 } else if (dst) {
100 dst[0] = '\0';
101 }
102 }
103
104 /*
105 * Copy domain to lttcomm_session_msg domain.
106 *
107 * If domain is unknown, default domain will be the kernel.
108 */
109 LTTNG_HIDDEN
110 void lttng_ctl_copy_lttng_domain(struct lttng_domain *dst,
111 struct lttng_domain *src)
112 {
113 if (src && dst) {
114 switch (src->type) {
115 case LTTNG_DOMAIN_KERNEL:
116 case LTTNG_DOMAIN_UST:
117 case LTTNG_DOMAIN_JUL:
118 case LTTNG_DOMAIN_LOG4J:
119 case LTTNG_DOMAIN_PYTHON:
120 memcpy(dst, src, sizeof(struct lttng_domain));
121 break;
122 default:
123 memset(dst, 0, sizeof(struct lttng_domain));
124 break;
125 }
126 }
127 }
128
129 /*
130 * Send lttcomm_session_msg to the session daemon.
131 *
132 * On success, returns the number of bytes sent (>=0)
133 * On error, returns -1
134 */
135 static int send_session_msg(struct lttcomm_session_msg *lsm)
136 {
137 int ret;
138
139 if (!connected) {
140 ret = -LTTNG_ERR_NO_SESSIOND;
141 goto end;
142 }
143
144 DBG("LSM cmd type : %d", lsm->cmd_type);
145
146 ret = lttcomm_send_creds_unix_sock(sessiond_socket, lsm,
147 sizeof(struct lttcomm_session_msg));
148 if (ret < 0) {
149 ret = -LTTNG_ERR_FATAL;
150 }
151
152 end:
153 return ret;
154 }
155
156 /*
157 * Send var len data to the session daemon.
158 *
159 * On success, returns the number of bytes sent (>=0)
160 * On error, returns -1
161 */
162 static int send_session_varlen(const void *data, size_t len)
163 {
164 int ret;
165
166 if (!connected) {
167 ret = -LTTNG_ERR_NO_SESSIOND;
168 goto end;
169 }
170
171 if (!data || !len) {
172 ret = 0;
173 goto end;
174 }
175
176 ret = lttcomm_send_unix_sock(sessiond_socket, data, len);
177 if (ret < 0) {
178 ret = -LTTNG_ERR_FATAL;
179 }
180
181 end:
182 return ret;
183 }
184
185 /*
186 * Send file descriptors to the session daemon.
187 *
188 * On success, returns the number of bytes sent (>=0)
189 * On error, returns -1
190 */
191 static int send_session_fds(const int *fds, size_t nb_fd)
192 {
193 int ret;
194
195 if (!connected) {
196 ret = -LTTNG_ERR_NO_SESSIOND;
197 goto end;
198 }
199
200 if (!fds || !nb_fd) {
201 ret = 0;
202 goto end;
203 }
204
205 ret = lttcomm_send_fds_unix_sock(sessiond_socket, fds, nb_fd);
206 if (ret < 0) {
207 ret = -LTTNG_ERR_FATAL;
208 }
209
210 end:
211 return ret;
212 }
213
214 /*
215 * Receive data from the sessiond socket.
216 *
217 * On success, returns the number of bytes received (>=0)
218 * On error, returns -1 (recvmsg() error) or -ENOTCONN
219 */
220 static int recv_data_sessiond(void *buf, size_t len)
221 {
222 int ret;
223
224 if (!connected) {
225 ret = -LTTNG_ERR_NO_SESSIOND;
226 goto end;
227 }
228
229 ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len);
230 if (ret < 0) {
231 ret = -LTTNG_ERR_FATAL;
232 }
233
234 end:
235 return ret;
236 }
237
238 /*
239 * Check if we are in the specified group.
240 *
241 * If yes return 1, else return -1.
242 */
243 LTTNG_HIDDEN
244 int lttng_check_tracing_group(void)
245 {
246 gid_t *grp_list, tracing_gid;
247 int grp_list_size, grp_id, i;
248 int ret = -1;
249 const char *grp_name = tracing_group;
250
251 /* Get GID of group 'tracing' */
252 if (utils_get_group_id(grp_name, false, &tracing_gid)) {
253 /* If grp_tracing is NULL, the group does not exist. */
254 goto end;
255 }
256
257 /* Get number of supplementary group IDs */
258 grp_list_size = getgroups(0, NULL);
259 if (grp_list_size < 0) {
260 PERROR("getgroups");
261 goto end;
262 }
263
264 /* Alloc group list of the right size */
265 grp_list = zmalloc(grp_list_size * sizeof(gid_t));
266 if (!grp_list) {
267 PERROR("malloc");
268 goto end;
269 }
270 grp_id = getgroups(grp_list_size, grp_list);
271 if (grp_id < 0) {
272 PERROR("getgroups");
273 goto free_list;
274 }
275
276 for (i = 0; i < grp_list_size; i++) {
277 if (grp_list[i] == tracing_gid) {
278 ret = 1;
279 break;
280 }
281 }
282
283 free_list:
284 free(grp_list);
285
286 end:
287 return ret;
288 }
289
290 static int check_enough_available_memory(size_t num_bytes_requested_per_cpu)
291 {
292 int ret;
293 long num_cpu;
294 size_t best_mem_info;
295 size_t num_bytes_requested_total;
296
297 /*
298 * Get the number of CPU currently online to compute the amount of
299 * memory needed to create a buffer for every CPU.
300 */
301 num_cpu = sysconf(_SC_NPROCESSORS_ONLN);
302 if (num_cpu == -1) {
303 goto error;
304 }
305
306 num_bytes_requested_total = num_bytes_requested_per_cpu * num_cpu;
307
308 /*
309 * Try to get the `MemAvail` field of `/proc/meminfo`. This is the most
310 * reliable estimate we can get but it is only exposed by the kernel
311 * since 3.14. (See Linux kernel commit:
312 * 34e431b0ae398fc54ea69ff85ec700722c9da773)
313 */
314 ret = utils_get_memory_available(&best_mem_info);
315 if (ret >= 0) {
316 goto success;
317 }
318
319 /*
320 * As a backup plan, use `MemTotal` field of `/proc/meminfo`. This
321 * is a sanity check for obvious user error.
322 */
323 ret = utils_get_memory_total(&best_mem_info);
324 if (ret >= 0) {
325 goto success;
326 }
327
328 error:
329 return -1;
330 success:
331 return best_mem_info >= num_bytes_requested_total;
332 }
333
334 /*
335 * Try connect to session daemon with sock_path.
336 *
337 * Return 0 on success, else -1
338 */
339 static int try_connect_sessiond(const char *sock_path)
340 {
341 int ret;
342
343 /* If socket exist, we check if the daemon listens for connect. */
344 ret = access(sock_path, F_OK);
345 if (ret < 0) {
346 /* Not alive */
347 goto error;
348 }
349
350 ret = lttcomm_connect_unix_sock(sock_path);
351 if (ret < 0) {
352 /* Not alive. */
353 goto error;
354 }
355
356 ret = lttcomm_close_unix_sock(ret);
357 if (ret < 0) {
358 PERROR("lttcomm_close_unix_sock");
359 }
360
361 return 0;
362
363 error:
364 return -1;
365 }
366
367 /*
368 * Set sessiond socket path by putting it in the global sessiond_sock_path
369 * variable.
370 *
371 * Returns 0 on success, negative value on failure (the sessiond socket path
372 * is somehow too long or ENOMEM).
373 */
374 static int set_session_daemon_path(void)
375 {
376 int in_tgroup = 0; /* In tracing group. */
377 uid_t uid;
378
379 uid = getuid();
380
381 if (uid != 0) {
382 /* Are we in the tracing group ? */
383 in_tgroup = lttng_check_tracing_group();
384 }
385
386 if ((uid == 0) || in_tgroup) {
387 lttng_ctl_copy_string(sessiond_sock_path,
388 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, sizeof(sessiond_sock_path));
389 }
390
391 if (uid != 0) {
392 int ret;
393
394 if (in_tgroup) {
395 /* Tracing group. */
396 ret = try_connect_sessiond(sessiond_sock_path);
397 if (ret >= 0) {
398 goto end;
399 }
400 /* Global session daemon not available... */
401 }
402 /* ...or not in tracing group (and not root), default */
403
404 /*
405 * With GNU C < 2.1, snprintf returns -1 if the target buffer
406 * is too small;
407 * With GNU C >= 2.1, snprintf returns the required size
408 * (excluding closing null)
409 */
410 ret = snprintf(sessiond_sock_path, sizeof(sessiond_sock_path),
411 DEFAULT_HOME_CLIENT_UNIX_SOCK, utils_get_home_dir());
412 if ((ret < 0) || (ret >= sizeof(sessiond_sock_path))) {
413 goto error;
414 }
415 }
416 end:
417 return 0;
418
419 error:
420 return -1;
421 }
422
423 /*
424 * Connect to the LTTng session daemon.
425 *
426 * On success, return 0. On error, return -1.
427 */
428 static int connect_sessiond(void)
429 {
430 int ret;
431
432 /* Don't try to connect if already connected. */
433 if (connected) {
434 return 0;
435 }
436
437 ret = set_session_daemon_path();
438 if (ret < 0) {
439 goto error;
440 }
441
442 /* Connect to the sesssion daemon. */
443 ret = lttcomm_connect_unix_sock(sessiond_sock_path);
444 if (ret < 0) {
445 goto error;
446 }
447
448 sessiond_socket = ret;
449 connected = 1;
450
451 return 0;
452
453 error:
454 return -1;
455 }
456
457 /*
458 * Clean disconnect from the session daemon.
459 *
460 * On success, return 0. On error, return -1.
461 */
462 static int disconnect_sessiond(void)
463 {
464 int ret = 0;
465
466 if (connected) {
467 ret = lttcomm_close_unix_sock(sessiond_socket);
468 sessiond_socket = 0;
469 connected = 0;
470 }
471
472 return ret;
473 }
474
475 static int recv_sessiond_optional_data(size_t len, void **user_buf,
476 size_t *user_len)
477 {
478 int ret = 0;
479 void *buf = NULL;
480
481 if (len) {
482 if (!user_len) {
483 ret = -LTTNG_ERR_INVALID;
484 goto end;
485 }
486
487 buf = zmalloc(len);
488 if (!buf) {
489 ret = -ENOMEM;
490 goto end;
491 }
492
493 ret = recv_data_sessiond(buf, len);
494 if (ret < 0) {
495 goto end;
496 }
497
498 if (!user_buf) {
499 ret = -LTTNG_ERR_INVALID;
500 goto end;
501 }
502
503 /* Move ownership of command header buffer to user. */
504 *user_buf = buf;
505 buf = NULL;
506 *user_len = len;
507 } else {
508 /* No command header. */
509 if (user_len) {
510 *user_len = 0;
511 }
512
513 if (user_buf) {
514 *user_buf = NULL;
515 }
516 }
517
518 end:
519 free(buf);
520 return ret;
521 }
522
523 /*
524 * Ask the session daemon a specific command and put the data into buf.
525 * Takes extra var. len. data and file descriptors as input to send to the
526 * session daemon.
527 *
528 * Return size of data (only payload, not header) or a negative error code.
529 */
530 LTTNG_HIDDEN
531 int lttng_ctl_ask_sessiond_fds_varlen(struct lttcomm_session_msg *lsm,
532 const int *fds, size_t nb_fd, const void *vardata,
533 size_t vardata_len, void **user_payload_buf,
534 void **user_cmd_header_buf, size_t *user_cmd_header_len)
535 {
536 int ret;
537 size_t payload_len;
538 struct lttcomm_lttng_msg llm;
539
540 ret = connect_sessiond();
541 if (ret < 0) {
542 ret = -LTTNG_ERR_NO_SESSIOND;
543 goto end;
544 }
545
546 /* Send command to session daemon */
547 ret = send_session_msg(lsm);
548 if (ret < 0) {
549 /* Ret value is a valid lttng error code. */
550 goto end;
551 }
552 /* Send var len data */
553 ret = send_session_varlen(vardata, vardata_len);
554 if (ret < 0) {
555 /* Ret value is a valid lttng error code. */
556 goto end;
557 }
558
559 /* Send fds */
560 ret = send_session_fds(fds, nb_fd);
561 if (ret < 0) {
562 /* Ret value is a valid lttng error code. */
563 goto end;
564 }
565
566 /* Get header from data transmission */
567 ret = recv_data_sessiond(&llm, sizeof(llm));
568 if (ret < 0) {
569 /* Ret value is a valid lttng error code. */
570 goto end;
571 }
572
573 /* Check error code if OK */
574 if (llm.ret_code != LTTNG_OK) {
575 ret = -llm.ret_code;
576 goto end;
577 }
578
579 /* Get command header from data transmission */
580 ret = recv_sessiond_optional_data(llm.cmd_header_size,
581 user_cmd_header_buf, user_cmd_header_len);
582 if (ret < 0) {
583 goto end;
584 }
585
586 /* Get payload from data transmission */
587 ret = recv_sessiond_optional_data(llm.data_size, user_payload_buf,
588 &payload_len);
589 if (ret < 0) {
590 goto end;
591 }
592
593 ret = llm.data_size;
594
595 end:
596 disconnect_sessiond();
597 return ret;
598 }
599
600 /*
601 * Create lttng handle and return pointer.
602 *
603 * The returned pointer will be NULL in case of malloc() error.
604 */
605 struct lttng_handle *lttng_create_handle(const char *session_name,
606 struct lttng_domain *domain)
607 {
608 struct lttng_handle *handle = NULL;
609
610 handle = zmalloc(sizeof(struct lttng_handle));
611 if (handle == NULL) {
612 PERROR("malloc handle");
613 goto end;
614 }
615
616 /* Copy session name */
617 lttng_ctl_copy_string(handle->session_name, session_name,
618 sizeof(handle->session_name));
619
620 /* Copy lttng domain or leave initialized to 0. */
621 if (domain) {
622 lttng_ctl_copy_lttng_domain(&handle->domain, domain);
623 }
624
625 end:
626 return handle;
627 }
628
629 /*
630 * Destroy handle by free(3) the pointer.
631 */
632 void lttng_destroy_handle(struct lttng_handle *handle)
633 {
634 free(handle);
635 }
636
637 /*
638 * Register an outside consumer.
639 *
640 * Returns size of returned session payload data or a negative error code.
641 */
642 int lttng_register_consumer(struct lttng_handle *handle,
643 const char *socket_path)
644 {
645 struct lttcomm_session_msg lsm;
646
647 if (handle == NULL || socket_path == NULL) {
648 return -LTTNG_ERR_INVALID;
649 }
650
651 memset(&lsm, 0, sizeof(lsm));
652 lsm.cmd_type = LTTNG_REGISTER_CONSUMER;
653 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
654 sizeof(lsm.session.name));
655 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
656
657 lttng_ctl_copy_string(lsm.u.reg.path, socket_path,
658 sizeof(lsm.u.reg.path));
659
660 return lttng_ctl_ask_sessiond(&lsm, NULL);
661 }
662
663 /*
664 * Start tracing for all traces of the session.
665 *
666 * Returns size of returned session payload data or a negative error code.
667 */
668 int lttng_start_tracing(const char *session_name)
669 {
670 struct lttcomm_session_msg lsm;
671
672 if (session_name == NULL) {
673 return -LTTNG_ERR_INVALID;
674 }
675
676 memset(&lsm, 0, sizeof(lsm));
677 lsm.cmd_type = LTTNG_START_TRACE;
678
679 lttng_ctl_copy_string(lsm.session.name, session_name,
680 sizeof(lsm.session.name));
681
682 return lttng_ctl_ask_sessiond(&lsm, NULL);
683 }
684
685 /*
686 * Stop tracing for all traces of the session.
687 */
688 static int _lttng_stop_tracing(const char *session_name, int wait)
689 {
690 int ret, data_ret;
691 struct lttcomm_session_msg lsm;
692
693 if (session_name == NULL) {
694 return -LTTNG_ERR_INVALID;
695 }
696
697 memset(&lsm, 0, sizeof(lsm));
698 lsm.cmd_type = LTTNG_STOP_TRACE;
699
700 lttng_ctl_copy_string(lsm.session.name, session_name,
701 sizeof(lsm.session.name));
702
703 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
704 if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
705 goto error;
706 }
707
708 if (!wait) {
709 goto end;
710 }
711
712 /* Check for data availability */
713 do {
714 data_ret = lttng_data_pending(session_name);
715 if (data_ret < 0) {
716 /* Return the data available call error. */
717 ret = data_ret;
718 goto error;
719 }
720
721 /*
722 * Data sleep time before retrying (in usec). Don't sleep if the
723 * call returned value indicates availability.
724 */
725 if (data_ret) {
726 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME);
727 }
728 } while (data_ret != 0);
729
730 end:
731 error:
732 return ret;
733 }
734
735 /*
736 * Stop tracing and wait for data availability.
737 */
738 int lttng_stop_tracing(const char *session_name)
739 {
740 return _lttng_stop_tracing(session_name, 1);
741 }
742
743 /*
744 * Stop tracing but _don't_ wait for data availability.
745 */
746 int lttng_stop_tracing_no_wait(const char *session_name)
747 {
748 return _lttng_stop_tracing(session_name, 0);
749 }
750
751 /*
752 * Add context to a channel.
753 *
754 * If the given channel is NULL, add the contexts to all channels.
755 * The event_name param is ignored.
756 *
757 * Returns the size of the returned payload data or a negative error code.
758 */
759 int lttng_add_context(struct lttng_handle *handle,
760 struct lttng_event_context *ctx, const char *event_name,
761 const char *channel_name)
762 {
763 int ret;
764 size_t len = 0;
765 char *buf = NULL;
766 struct lttcomm_session_msg lsm;
767
768 /* Safety check. Both are mandatory. */
769 if (handle == NULL || ctx == NULL) {
770 ret = -LTTNG_ERR_INVALID;
771 goto end;
772 }
773
774 memset(&lsm, 0, sizeof(lsm));
775 lsm.cmd_type = LTTNG_ADD_CONTEXT;
776
777 /* If no channel name, send empty string. */
778 if (channel_name == NULL) {
779 lttng_ctl_copy_string(lsm.u.context.channel_name, "",
780 sizeof(lsm.u.context.channel_name));
781 } else {
782 lttng_ctl_copy_string(lsm.u.context.channel_name, channel_name,
783 sizeof(lsm.u.context.channel_name));
784 }
785
786 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
787 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
788 sizeof(lsm.session.name));
789
790 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
791 size_t provider_len, ctx_len;
792 const char *provider_name = ctx->u.app_ctx.provider_name;
793 const char *ctx_name = ctx->u.app_ctx.ctx_name;
794
795 if (!provider_name || !ctx_name) {
796 ret = -LTTNG_ERR_INVALID;
797 goto end;
798 }
799
800 provider_len = strlen(provider_name);
801 if (provider_len == 0) {
802 ret = -LTTNG_ERR_INVALID;
803 goto end;
804 }
805 lsm.u.context.provider_name_len = provider_len;
806
807 ctx_len = strlen(ctx_name);
808 if (ctx_len == 0) {
809 ret = -LTTNG_ERR_INVALID;
810 goto end;
811 }
812 lsm.u.context.context_name_len = ctx_len;
813
814 len = provider_len + ctx_len;
815 buf = zmalloc(len);
816 if (!buf) {
817 ret = -LTTNG_ERR_NOMEM;
818 goto end;
819 }
820
821 memcpy(buf, provider_name, provider_len);
822 memcpy(buf + provider_len, ctx_name, ctx_len);
823 }
824 memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context));
825
826 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
827 /*
828 * Don't leak application addresses to the sessiond.
829 * This is only necessary when ctx is for an app ctx otherwise
830 * the values inside the union (type & config) are overwritten.
831 */
832 lsm.u.context.ctx.u.app_ctx.provider_name = NULL;
833 lsm.u.context.ctx.u.app_ctx.ctx_name = NULL;
834 }
835
836 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, buf, len, NULL);
837 end:
838 free(buf);
839 return ret;
840 }
841
842 /*
843 * Enable event(s) for a channel.
844 *
845 * If no event name is specified, all events are enabled.
846 * If no channel name is specified, the default 'channel0' is used.
847 *
848 * Returns size of returned session payload data or a negative error code.
849 */
850 int lttng_enable_event(struct lttng_handle *handle,
851 struct lttng_event *ev, const char *channel_name)
852 {
853 return lttng_enable_event_with_exclusions(handle, ev, channel_name,
854 NULL, 0, NULL);
855 }
856
857 /*
858 * Create or enable an event with a filter expression.
859 *
860 * Return negative error value on error.
861 * Return size of returned session payload data if OK.
862 */
863 int lttng_enable_event_with_filter(struct lttng_handle *handle,
864 struct lttng_event *event, const char *channel_name,
865 const char *filter_expression)
866 {
867 return lttng_enable_event_with_exclusions(handle, event, channel_name,
868 filter_expression, 0, NULL);
869 }
870
871 /*
872 * Depending on the event, return a newly allocated agent filter expression or
873 * NULL if not applicable.
874 *
875 * An event with NO loglevel and the name is * will return NULL.
876 */
877 static char *set_agent_filter(const char *filter, struct lttng_event *ev)
878 {
879 int err;
880 char *agent_filter = NULL;
881
882 assert(ev);
883
884 /* Don't add filter for the '*' event. */
885 if (strcmp(ev->name, "*") != 0) {
886 if (filter) {
887 err = asprintf(&agent_filter, "(%s) && (logger_name == \"%s\")", filter,
888 ev->name);
889 } else {
890 err = asprintf(&agent_filter, "logger_name == \"%s\"", ev->name);
891 }
892 if (err < 0) {
893 PERROR("asprintf");
894 goto error;
895 }
896 }
897
898 /* Add loglevel filtering if any for the JUL domain. */
899 if (ev->loglevel_type != LTTNG_EVENT_LOGLEVEL_ALL) {
900 char *op;
901
902 if (ev->loglevel_type == LTTNG_EVENT_LOGLEVEL_RANGE) {
903 op = ">=";
904 } else {
905 op = "==";
906 }
907
908 if (filter || agent_filter) {
909 char *new_filter;
910
911 err = asprintf(&new_filter, "(%s) && (int_loglevel %s %d)",
912 agent_filter ? agent_filter : filter, op,
913 ev->loglevel);
914 if (agent_filter) {
915 free(agent_filter);
916 }
917 agent_filter = new_filter;
918 } else {
919 err = asprintf(&agent_filter, "int_loglevel %s %d", op,
920 ev->loglevel);
921 }
922 if (err < 0) {
923 PERROR("asprintf");
924 goto error;
925 }
926 }
927
928 return agent_filter;
929 error:
930 free(agent_filter);
931 return NULL;
932 }
933
934 /*
935 * Generate the filter bytecode from a given filter expression string. Put the
936 * newly allocated parser context in ctxp and populate the lsm object with the
937 * expression len.
938 *
939 * Return 0 on success else a LTTNG_ERR_* code and ctxp is untouched.
940 */
941 static int generate_filter(char *filter_expression,
942 struct lttcomm_session_msg *lsm, struct filter_parser_ctx **ctxp)
943 {
944 int ret;
945 struct filter_parser_ctx *ctx = NULL;
946 FILE *fmem = NULL;
947
948 assert(filter_expression);
949 assert(lsm);
950 assert(ctxp);
951
952 /*
953 * Casting const to non-const, as the underlying function will use it in
954 * read-only mode.
955 */
956 fmem = lttng_fmemopen((void *) filter_expression,
957 strlen(filter_expression), "r");
958 if (!fmem) {
959 fprintf(stderr, "Error opening memory as stream\n");
960 ret = -LTTNG_ERR_FILTER_NOMEM;
961 goto error;
962 }
963 ctx = filter_parser_ctx_alloc(fmem);
964 if (!ctx) {
965 fprintf(stderr, "Error allocating parser\n");
966 ret = -LTTNG_ERR_FILTER_NOMEM;
967 goto filter_alloc_error;
968 }
969 ret = filter_parser_ctx_append_ast(ctx);
970 if (ret) {
971 fprintf(stderr, "Parse error\n");
972 ret = -LTTNG_ERR_FILTER_INVAL;
973 goto parse_error;
974 }
975 if (print_xml) {
976 ret = filter_visitor_print_xml(ctx, stdout, 0);
977 if (ret) {
978 fflush(stdout);
979 fprintf(stderr, "XML print error\n");
980 ret = -LTTNG_ERR_FILTER_INVAL;
981 goto parse_error;
982 }
983 }
984
985 dbg_printf("Generating IR... ");
986 fflush(stdout);
987 ret = filter_visitor_ir_generate(ctx);
988 if (ret) {
989 fprintf(stderr, "Generate IR error\n");
990 ret = -LTTNG_ERR_FILTER_INVAL;
991 goto parse_error;
992 }
993 dbg_printf("done\n");
994
995 dbg_printf("Validating IR... ");
996 fflush(stdout);
997 ret = filter_visitor_ir_check_binary_op_nesting(ctx);
998 if (ret) {
999 ret = -LTTNG_ERR_FILTER_INVAL;
1000 goto parse_error;
1001 }
1002
1003 /* Normalize globbing patterns in the expression. */
1004 ret = filter_visitor_ir_normalize_glob_patterns(ctx);
1005 if (ret) {
1006 ret = -LTTNG_ERR_FILTER_INVAL;
1007 goto parse_error;
1008 }
1009
1010 /* Validate strings used as literals in the expression. */
1011 ret = filter_visitor_ir_validate_string(ctx);
1012 if (ret) {
1013 ret = -LTTNG_ERR_FILTER_INVAL;
1014 goto parse_error;
1015 }
1016
1017 /* Validate globbing patterns in the expression. */
1018 ret = filter_visitor_ir_validate_globbing(ctx);
1019 if (ret) {
1020 ret = -LTTNG_ERR_FILTER_INVAL;
1021 goto parse_error;
1022 }
1023
1024 dbg_printf("done\n");
1025
1026 dbg_printf("Generating bytecode... ");
1027 fflush(stdout);
1028 ret = filter_visitor_bytecode_generate(ctx);
1029 if (ret) {
1030 fprintf(stderr, "Generate bytecode error\n");
1031 ret = -LTTNG_ERR_FILTER_INVAL;
1032 goto parse_error;
1033 }
1034 dbg_printf("done\n");
1035 dbg_printf("Size of bytecode generated: %u bytes.\n",
1036 bytecode_get_len(&ctx->bytecode->b));
1037
1038 lsm->u.enable.bytecode_len = sizeof(ctx->bytecode->b)
1039 + bytecode_get_len(&ctx->bytecode->b);
1040 lsm->u.enable.expression_len = strlen(filter_expression) + 1;
1041
1042 /* No need to keep the memory stream. */
1043 if (fclose(fmem) != 0) {
1044 PERROR("fclose");
1045 }
1046
1047 *ctxp = ctx;
1048 return 0;
1049
1050 parse_error:
1051 filter_ir_free(ctx);
1052 filter_parser_ctx_free(ctx);
1053 filter_alloc_error:
1054 if (fclose(fmem) != 0) {
1055 PERROR("fclose");
1056 }
1057 error:
1058 return ret;
1059 }
1060
1061 /*
1062 * Enable event(s) for a channel, possibly with exclusions and a filter.
1063 * If no event name is specified, all events are enabled.
1064 * If no channel name is specified, the default name is used.
1065 * If filter expression is not NULL, the filter is set for the event.
1066 * If exclusion count is not zero, the exclusions are set for the event.
1067 * Returns size of returned session payload data or a negative error code.
1068 */
1069 int lttng_enable_event_with_exclusions(struct lttng_handle *handle,
1070 struct lttng_event *ev, const char *channel_name,
1071 const char *original_filter_expression,
1072 int exclusion_count, char **exclusion_list)
1073 {
1074 struct lttcomm_session_msg lsm;
1075 struct lttng_dynamic_buffer send_buffer;
1076 int ret = 0, i, fd_to_send = -1;
1077 bool send_fd = false;
1078 unsigned int free_filter_expression = 0;
1079 struct filter_parser_ctx *ctx = NULL;
1080
1081 /*
1082 * We have either a filter or some exclusions, so we need to set up
1083 * a variable-length memory block from where to send the data.
1084 */
1085 lttng_dynamic_buffer_init(&send_buffer);
1086
1087 /*
1088 * Cast as non-const since we may replace the filter expression
1089 * by a dynamically allocated string. Otherwise, the original
1090 * string is not modified.
1091 */
1092 char *filter_expression = (char *) original_filter_expression;
1093
1094 if (handle == NULL || ev == NULL) {
1095 ret = -LTTNG_ERR_INVALID;
1096 goto error;
1097 }
1098
1099 /*
1100 * Empty filter string will always be rejected by the parser
1101 * anyway, so treat this corner-case early to eliminate
1102 * lttng_fmemopen error for 0-byte allocation.
1103 */
1104 if (filter_expression && filter_expression[0] == '\0') {
1105 ret = -LTTNG_ERR_INVALID;
1106 goto error;
1107 }
1108
1109 memset(&lsm, 0, sizeof(lsm));
1110
1111 /* If no channel name, send empty string. */
1112 if (channel_name == NULL) {
1113 lttng_ctl_copy_string(lsm.u.enable.channel_name, "",
1114 sizeof(lsm.u.enable.channel_name));
1115 } else {
1116 lttng_ctl_copy_string(lsm.u.enable.channel_name, channel_name,
1117 sizeof(lsm.u.enable.channel_name));
1118 }
1119
1120 lsm.cmd_type = LTTNG_ENABLE_EVENT;
1121 if (ev->name[0] == '\0') {
1122 /* Enable all events */
1123 lttng_ctl_copy_string(ev->name, "*", sizeof(ev->name));
1124 }
1125
1126 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1127 /* FIXME: copying non-packed struct to packed struct. */
1128 memcpy(&lsm.u.enable.event, ev, sizeof(lsm.u.enable.event));
1129
1130 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1131 sizeof(lsm.session.name));
1132 lsm.u.enable.exclusion_count = exclusion_count;
1133 lsm.u.enable.bytecode_len = 0;
1134
1135 /* Parse filter expression. */
1136 if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
1137 || handle->domain.type == LTTNG_DOMAIN_LOG4J
1138 || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1139 if (handle->domain.type == LTTNG_DOMAIN_JUL ||
1140 handle->domain.type == LTTNG_DOMAIN_LOG4J ||
1141 handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1142 char *agent_filter;
1143
1144 /* Setup JUL filter if needed. */
1145 agent_filter = set_agent_filter(filter_expression, ev);
1146 if (!agent_filter) {
1147 if (!filter_expression) {
1148 /*
1149 * No JUL and no filter, just skip
1150 * everything below.
1151 */
1152 goto ask_sessiond;
1153 }
1154 } else {
1155 /*
1156 * With an agent filter, the original filter has
1157 * been added to it thus replace the filter
1158 * expression.
1159 */
1160 filter_expression = agent_filter;
1161 free_filter_expression = 1;
1162 }
1163 }
1164
1165 ret = generate_filter(filter_expression, &lsm, &ctx);
1166 if (ret) {
1167 goto filter_error;
1168 }
1169 }
1170
1171 ret = lttng_dynamic_buffer_set_capacity(&send_buffer,
1172 lsm.u.enable.bytecode_len
1173 + lsm.u.enable.expression_len
1174 + LTTNG_SYMBOL_NAME_LEN * exclusion_count);
1175 if (ret) {
1176 ret = -LTTNG_ERR_EXCLUSION_NOMEM;
1177 goto mem_error;
1178 }
1179
1180 /* Put exclusion names first in the data. */
1181 for (i = 0; i < exclusion_count; i++) {
1182 size_t exclusion_len;
1183
1184 exclusion_len = lttng_strnlen(*(exclusion_list + i),
1185 LTTNG_SYMBOL_NAME_LEN);
1186 if (exclusion_len == LTTNG_SYMBOL_NAME_LEN) {
1187 /* Exclusion is not NULL-terminated. */
1188 ret = -LTTNG_ERR_INVALID;
1189 goto mem_error;
1190 }
1191
1192 ret = lttng_dynamic_buffer_append(&send_buffer,
1193 *(exclusion_list + i),
1194 LTTNG_SYMBOL_NAME_LEN);
1195 if (ret) {
1196 goto mem_error;
1197 }
1198 }
1199
1200 /* Add filter expression next. */
1201 if (filter_expression) {
1202 ret = lttng_dynamic_buffer_append(&send_buffer,
1203 filter_expression, lsm.u.enable.expression_len);
1204 if (ret) {
1205 goto mem_error;
1206 }
1207 }
1208 /* Add filter bytecode next. */
1209 if (ctx && lsm.u.enable.bytecode_len != 0) {
1210 ret = lttng_dynamic_buffer_append(&send_buffer,
1211 &ctx->bytecode->b, lsm.u.enable.bytecode_len);
1212 if (ret) {
1213 goto mem_error;
1214 }
1215 }
1216 if (ev->extended.ptr) {
1217 struct lttng_event_extended *ev_ext =
1218 (struct lttng_event_extended *) ev->extended.ptr;
1219
1220 if (ev_ext->probe_location) {
1221 /*
1222 * lttng_userspace_probe_location_serialize returns the
1223 * number of bytes that was appended to the buffer.
1224 */
1225 ret = lttng_userspace_probe_location_serialize(
1226 ev_ext->probe_location, &send_buffer,
1227 &fd_to_send);
1228 if (ret < 0) {
1229 goto mem_error;
1230 }
1231
1232 send_fd = fd_to_send >= 0;
1233 /*
1234 * Set the size of the userspace probe location element
1235 * of the buffer so that the receiving side knows where
1236 * to split it.
1237 */
1238 lsm.u.enable.userspace_probe_location_len = ret;
1239 }
1240 }
1241
1242 ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm,
1243 send_fd ? &fd_to_send : NULL,
1244 send_fd ? 1 : 0,
1245 send_buffer.size ? send_buffer.data : NULL,
1246 send_buffer.size, NULL, NULL, 0);
1247
1248 mem_error:
1249 if (filter_expression && ctx) {
1250 filter_bytecode_free(ctx);
1251 filter_ir_free(ctx);
1252 filter_parser_ctx_free(ctx);
1253 }
1254 filter_error:
1255 if (free_filter_expression) {
1256 /*
1257 * The filter expression has been replaced and must be freed as
1258 * it is not the original filter expression received as a
1259 * parameter.
1260 */
1261 free(filter_expression);
1262 }
1263 error:
1264 /*
1265 * Return directly to the caller and don't ask the sessiond since
1266 * something went wrong in the parsing of data above.
1267 */
1268 lttng_dynamic_buffer_reset(&send_buffer);
1269 return ret;
1270
1271 ask_sessiond:
1272 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1273 return ret;
1274 }
1275
1276 int lttng_disable_event_ext(struct lttng_handle *handle,
1277 struct lttng_event *ev, const char *channel_name,
1278 const char *original_filter_expression)
1279 {
1280 struct lttcomm_session_msg lsm;
1281 char *varlen_data;
1282 int ret = 0;
1283 unsigned int free_filter_expression = 0;
1284 struct filter_parser_ctx *ctx = NULL;
1285 /*
1286 * Cast as non-const since we may replace the filter expression
1287 * by a dynamically allocated string. Otherwise, the original
1288 * string is not modified.
1289 */
1290 char *filter_expression = (char *) original_filter_expression;
1291
1292 if (handle == NULL || ev == NULL) {
1293 ret = -LTTNG_ERR_INVALID;
1294 goto error;
1295 }
1296
1297 /*
1298 * Empty filter string will always be rejected by the parser
1299 * anyway, so treat this corner-case early to eliminate
1300 * lttng_fmemopen error for 0-byte allocation.
1301 */
1302 if (filter_expression && filter_expression[0] == '\0') {
1303 ret = -LTTNG_ERR_INVALID;
1304 goto error;
1305 }
1306
1307 memset(&lsm, 0, sizeof(lsm));
1308
1309 /* If no channel name, send empty string. */
1310 if (channel_name == NULL) {
1311 lttng_ctl_copy_string(lsm.u.disable.channel_name, "",
1312 sizeof(lsm.u.disable.channel_name));
1313 } else {
1314 lttng_ctl_copy_string(lsm.u.disable.channel_name, channel_name,
1315 sizeof(lsm.u.disable.channel_name));
1316 }
1317
1318 lsm.cmd_type = LTTNG_DISABLE_EVENT;
1319
1320 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1321 /* FIXME: copying non-packed struct to packed struct. */
1322 memcpy(&lsm.u.disable.event, ev, sizeof(lsm.u.disable.event));
1323
1324 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1325 sizeof(lsm.session.name));
1326 lsm.u.disable.bytecode_len = 0;
1327
1328 /*
1329 * For the JUL domain, a filter is enforced except for the
1330 * disable all event. This is done to avoid having the event in
1331 * all sessions thus filtering by logger name.
1332 */
1333 if (filter_expression == NULL &&
1334 (handle->domain.type != LTTNG_DOMAIN_JUL &&
1335 handle->domain.type != LTTNG_DOMAIN_LOG4J &&
1336 handle->domain.type != LTTNG_DOMAIN_PYTHON)) {
1337 goto ask_sessiond;
1338 }
1339
1340 /*
1341 * We have a filter, so we need to set up a variable-length
1342 * memory block from where to send the data.
1343 */
1344
1345 /* Parse filter expression */
1346 if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
1347 || handle->domain.type == LTTNG_DOMAIN_LOG4J
1348 || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1349 if (handle->domain.type == LTTNG_DOMAIN_JUL ||
1350 handle->domain.type == LTTNG_DOMAIN_LOG4J ||
1351 handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1352 char *agent_filter;
1353
1354 /* Setup JUL filter if needed. */
1355 agent_filter = set_agent_filter(filter_expression, ev);
1356 if (!agent_filter) {
1357 if (!filter_expression) {
1358 /*
1359 * No JUL and no filter, just skip
1360 * everything below.
1361 */
1362 goto ask_sessiond;
1363 }
1364 } else {
1365 /*
1366 * With a JUL filter, the original filter has
1367 * been added to it thus replace the filter
1368 * expression.
1369 */
1370 filter_expression = agent_filter;
1371 free_filter_expression = 1;
1372 }
1373 }
1374
1375 ret = generate_filter(filter_expression, &lsm, &ctx);
1376 if (ret) {
1377 goto filter_error;
1378 }
1379 }
1380
1381 varlen_data = zmalloc(lsm.u.disable.bytecode_len
1382 + lsm.u.disable.expression_len);
1383 if (!varlen_data) {
1384 ret = -LTTNG_ERR_EXCLUSION_NOMEM;
1385 goto mem_error;
1386 }
1387
1388 /* Add filter expression. */
1389 if (lsm.u.disable.expression_len != 0) {
1390 memcpy(varlen_data,
1391 filter_expression,
1392 lsm.u.disable.expression_len);
1393 }
1394 /* Add filter bytecode next. */
1395 if (ctx && lsm.u.disable.bytecode_len != 0) {
1396 memcpy(varlen_data
1397 + lsm.u.disable.expression_len,
1398 &ctx->bytecode->b,
1399 lsm.u.disable.bytecode_len);
1400 }
1401
1402 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, varlen_data,
1403 lsm.u.disable.bytecode_len + lsm.u.disable.expression_len, NULL);
1404 free(varlen_data);
1405
1406 mem_error:
1407 if (filter_expression && ctx) {
1408 filter_bytecode_free(ctx);
1409 filter_ir_free(ctx);
1410 filter_parser_ctx_free(ctx);
1411 }
1412 filter_error:
1413 if (free_filter_expression) {
1414 /*
1415 * The filter expression has been replaced and must be freed as
1416 * it is not the original filter expression received as a
1417 * parameter.
1418 */
1419 free(filter_expression);
1420 }
1421 error:
1422 /*
1423 * Return directly to the caller and don't ask the sessiond since
1424 * something went wrong in the parsing of data above.
1425 */
1426 return ret;
1427
1428 ask_sessiond:
1429 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1430 return ret;
1431 }
1432
1433 /*
1434 * Disable event(s) of a channel and domain.
1435 * If no event name is specified, all events are disabled.
1436 * If no channel name is specified, the default 'channel0' is used.
1437 * Returns size of returned session payload data or a negative error code.
1438 */
1439 int lttng_disable_event(struct lttng_handle *handle, const char *name,
1440 const char *channel_name)
1441 {
1442 struct lttng_event ev;
1443
1444 memset(&ev, 0, sizeof(ev));
1445 ev.loglevel = -1;
1446 ev.type = LTTNG_EVENT_ALL;
1447 lttng_ctl_copy_string(ev.name, name, sizeof(ev.name));
1448 return lttng_disable_event_ext(handle, &ev, channel_name, NULL);
1449 }
1450
1451 struct lttng_channel *lttng_channel_create(struct lttng_domain *domain)
1452 {
1453 struct lttng_channel *channel = NULL;
1454 struct lttng_channel_extended *extended = NULL;
1455
1456 if (!domain) {
1457 goto error;
1458 }
1459
1460 /* Validate domain. */
1461 switch (domain->type) {
1462 case LTTNG_DOMAIN_UST:
1463 switch (domain->buf_type) {
1464 case LTTNG_BUFFER_PER_UID:
1465 case LTTNG_BUFFER_PER_PID:
1466 break;
1467 default:
1468 goto error;
1469 }
1470 break;
1471 case LTTNG_DOMAIN_KERNEL:
1472 if (domain->buf_type != LTTNG_BUFFER_GLOBAL) {
1473 goto error;
1474 }
1475 break;
1476 default:
1477 goto error;
1478 }
1479
1480 channel = zmalloc(sizeof(*channel));
1481 if (!channel) {
1482 goto error;
1483 }
1484
1485 extended = zmalloc(sizeof(*extended));
1486 if (!extended) {
1487 goto error;
1488 }
1489
1490 channel->attr.extended.ptr = extended;
1491
1492 lttng_channel_set_default_attr(domain, &channel->attr);
1493 return channel;
1494 error:
1495 free(channel);
1496 free(extended);
1497 return NULL;
1498 }
1499
1500 void lttng_channel_destroy(struct lttng_channel *channel)
1501 {
1502 if (!channel) {
1503 return;
1504 }
1505
1506 if (channel->attr.extended.ptr) {
1507 free(channel->attr.extended.ptr);
1508 }
1509 free(channel);
1510 }
1511
1512 /*
1513 * Enable channel per domain
1514 * Returns size of returned session payload data or a negative error code.
1515 */
1516 int lttng_enable_channel(struct lttng_handle *handle,
1517 struct lttng_channel *in_chan)
1518 {
1519 struct lttcomm_session_msg lsm;
1520 size_t total_buffer_size_needed_per_cpu = 0;
1521
1522 /* NULL arguments are forbidden. No default values. */
1523 if (handle == NULL || in_chan == NULL) {
1524 return -LTTNG_ERR_INVALID;
1525 }
1526
1527 memset(&lsm, 0, sizeof(lsm));
1528 memcpy(&lsm.u.channel.chan, in_chan, sizeof(lsm.u.channel.chan));
1529 lsm.u.channel.chan.attr.extended.ptr = NULL;
1530
1531 if (!in_chan->attr.extended.ptr) {
1532 struct lttng_channel *channel;
1533 struct lttng_channel_extended *extended;
1534
1535 channel = lttng_channel_create(&handle->domain);
1536 if (!channel) {
1537 return -LTTNG_ERR_NOMEM;
1538 }
1539
1540 /*
1541 * Create a new channel in order to use default extended
1542 * attribute values.
1543 */
1544 extended = (struct lttng_channel_extended *)
1545 channel->attr.extended.ptr;
1546 memcpy(&lsm.u.channel.extended, extended, sizeof(*extended));
1547 lttng_channel_destroy(channel);
1548 } else {
1549 struct lttng_channel_extended *extended;
1550
1551 extended = (struct lttng_channel_extended *)
1552 in_chan->attr.extended.ptr;
1553 memcpy(&lsm.u.channel.extended, extended, sizeof(*extended));
1554 }
1555
1556 /*
1557 * Verify that the amount of memory required to create the requested
1558 * buffer is available on the system at the moment.
1559 */
1560 total_buffer_size_needed_per_cpu = lsm.u.channel.chan.attr.num_subbuf *
1561 lsm.u.channel.chan.attr.subbuf_size;
1562 if (!check_enough_available_memory(total_buffer_size_needed_per_cpu)) {
1563 return -LTTNG_ERR_NOMEM;
1564 }
1565
1566 lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
1567 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1568
1569 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1570 sizeof(lsm.session.name));
1571
1572 return lttng_ctl_ask_sessiond(&lsm, NULL);
1573 }
1574
1575 /*
1576 * All tracing will be stopped for registered events of the channel.
1577 * Returns size of returned session payload data or a negative error code.
1578 */
1579 int lttng_disable_channel(struct lttng_handle *handle, const char *name)
1580 {
1581 struct lttcomm_session_msg lsm;
1582
1583 /* Safety check. Both are mandatory. */
1584 if (handle == NULL || name == NULL) {
1585 return -LTTNG_ERR_INVALID;
1586 }
1587
1588 memset(&lsm, 0, sizeof(lsm));
1589
1590 lsm.cmd_type = LTTNG_DISABLE_CHANNEL;
1591
1592 lttng_ctl_copy_string(lsm.u.disable.channel_name, name,
1593 sizeof(lsm.u.disable.channel_name));
1594
1595 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1596
1597 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1598 sizeof(lsm.session.name));
1599
1600 return lttng_ctl_ask_sessiond(&lsm, NULL);
1601 }
1602
1603 /*
1604 * Add PID to session tracker.
1605 * Return 0 on success else a negative LTTng error code.
1606 */
1607 int lttng_track_pid(struct lttng_handle *handle, int pid)
1608 {
1609 struct lttcomm_session_msg lsm;
1610
1611 /* NULL arguments are forbidden. No default values. */
1612 if (handle == NULL) {
1613 return -LTTNG_ERR_INVALID;
1614 }
1615
1616 memset(&lsm, 0, sizeof(lsm));
1617
1618 lsm.cmd_type = LTTNG_TRACK_PID;
1619 lsm.u.pid_tracker.pid = pid;
1620
1621 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1622
1623 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1624 sizeof(lsm.session.name));
1625
1626 return lttng_ctl_ask_sessiond(&lsm, NULL);
1627 }
1628
1629 /*
1630 * Remove PID from session tracker.
1631 * Return 0 on success else a negative LTTng error code.
1632 */
1633 int lttng_untrack_pid(struct lttng_handle *handle, int pid)
1634 {
1635 struct lttcomm_session_msg lsm;
1636
1637 /* NULL arguments are forbidden. No default values. */
1638 if (handle == NULL) {
1639 return -LTTNG_ERR_INVALID;
1640 }
1641
1642 memset(&lsm, 0, sizeof(lsm));
1643
1644 lsm.cmd_type = LTTNG_UNTRACK_PID;
1645 lsm.u.pid_tracker.pid = pid;
1646
1647 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1648
1649 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1650 sizeof(lsm.session.name));
1651
1652 return lttng_ctl_ask_sessiond(&lsm, NULL);
1653 }
1654
1655 /*
1656 * Lists all available tracepoints of domain.
1657 * Sets the contents of the events array.
1658 * Returns the number of lttng_event entries in events;
1659 * on error, returns a negative value.
1660 */
1661 int lttng_list_tracepoints(struct lttng_handle *handle,
1662 struct lttng_event **events)
1663 {
1664 int ret;
1665 struct lttcomm_session_msg lsm;
1666
1667 if (handle == NULL) {
1668 return -LTTNG_ERR_INVALID;
1669 }
1670
1671 memset(&lsm, 0, sizeof(lsm));
1672 lsm.cmd_type = LTTNG_LIST_TRACEPOINTS;
1673 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1674
1675 ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
1676 if (ret < 0) {
1677 return ret;
1678 }
1679
1680 return ret / sizeof(struct lttng_event);
1681 }
1682
1683 /*
1684 * Lists all available tracepoint fields of domain.
1685 * Sets the contents of the event field array.
1686 * Returns the number of lttng_event_field entries in events;
1687 * on error, returns a negative value.
1688 */
1689 int lttng_list_tracepoint_fields(struct lttng_handle *handle,
1690 struct lttng_event_field **fields)
1691 {
1692 int ret;
1693 struct lttcomm_session_msg lsm;
1694
1695 if (handle == NULL) {
1696 return -LTTNG_ERR_INVALID;
1697 }
1698
1699 memset(&lsm, 0, sizeof(lsm));
1700 lsm.cmd_type = LTTNG_LIST_TRACEPOINT_FIELDS;
1701 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1702
1703 ret = lttng_ctl_ask_sessiond(&lsm, (void **) fields);
1704 if (ret < 0) {
1705 return ret;
1706 }
1707
1708 return ret / sizeof(struct lttng_event_field);
1709 }
1710
1711 /*
1712 * Lists all available kernel system calls. Allocates and sets the contents of
1713 * the events array.
1714 *
1715 * Returns the number of lttng_event entries in events; on error, returns a
1716 * negative value.
1717 */
1718 int lttng_list_syscalls(struct lttng_event **events)
1719 {
1720 int ret;
1721 struct lttcomm_session_msg lsm;
1722
1723 if (!events) {
1724 return -LTTNG_ERR_INVALID;
1725 }
1726
1727 memset(&lsm, 0, sizeof(lsm));
1728 lsm.cmd_type = LTTNG_LIST_SYSCALLS;
1729 /* Force kernel domain for system calls. */
1730 lsm.domain.type = LTTNG_DOMAIN_KERNEL;
1731
1732 ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
1733 if (ret < 0) {
1734 return ret;
1735 }
1736
1737 return ret / sizeof(struct lttng_event);
1738 }
1739
1740 /*
1741 * Returns a human readable string describing
1742 * the error code (a negative value).
1743 */
1744 const char *lttng_strerror(int code)
1745 {
1746 return error_get_str(code);
1747 }
1748
1749 enum lttng_error_code lttng_create_session_ext(
1750 struct lttng_session_descriptor *session_descriptor)
1751 {
1752 enum lttng_error_code ret_code;
1753 struct lttcomm_session_msg lsm = {
1754 .cmd_type = LTTNG_CREATE_SESSION_EXT,
1755 };
1756 void *reply = NULL;
1757 struct lttng_buffer_view reply_view;
1758 int reply_ret;
1759 bool sessiond_must_generate_ouput;
1760 struct lttng_dynamic_buffer payload;
1761 int ret;
1762 size_t descriptor_size;
1763 struct lttng_session_descriptor *descriptor_reply = NULL;
1764
1765 lttng_dynamic_buffer_init(&payload);
1766 if (!session_descriptor) {
1767 ret_code = LTTNG_ERR_INVALID;
1768 goto end;
1769 }
1770
1771 sessiond_must_generate_ouput =
1772 !lttng_session_descriptor_is_output_destination_initialized(
1773 session_descriptor);
1774 if (sessiond_must_generate_ouput) {
1775 const char *home_dir = utils_get_home_dir();
1776 size_t home_dir_len = home_dir ? strlen(home_dir) + 1 : 0;
1777
1778 if (!home_dir || home_dir_len > LTTNG_PATH_MAX) {
1779 ret_code = LTTNG_ERR_FATAL;
1780 goto end;
1781 }
1782
1783 lsm.u.create_session.home_dir_size = (uint16_t) home_dir_len;
1784 ret = lttng_dynamic_buffer_append(&payload, home_dir,
1785 home_dir_len);
1786 if (ret) {
1787 ret_code = LTTNG_ERR_NOMEM;
1788 goto end;
1789 }
1790 }
1791
1792 descriptor_size = payload.size;
1793 ret = lttng_session_descriptor_serialize(session_descriptor,
1794 &payload);
1795 if (ret) {
1796 ret_code = LTTNG_ERR_INVALID;
1797 goto end;
1798 }
1799 descriptor_size = payload.size - descriptor_size;
1800 lsm.u.create_session.session_descriptor_size = descriptor_size;
1801
1802 /* Command returns a session descriptor on success. */
1803 reply_ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, payload.data,
1804 payload.size, &reply);
1805 if (reply_ret < 0) {
1806 ret_code = -reply_ret;
1807 goto end;
1808 } else if (reply_ret == 0) {
1809 /* Socket unexpectedly closed by the session daemon. */
1810 ret_code = LTTNG_ERR_FATAL;
1811 goto end;
1812 }
1813
1814 reply_view = lttng_buffer_view_init(reply, 0, reply_ret);
1815 ret = lttng_session_descriptor_create_from_buffer(&reply_view,
1816 &descriptor_reply);
1817 if (ret < 0) {
1818 ret_code = LTTNG_ERR_FATAL;
1819 goto end;
1820 }
1821 ret_code = LTTNG_OK;
1822 lttng_session_descriptor_assign(session_descriptor, descriptor_reply);
1823 end:
1824 free(reply);
1825 lttng_dynamic_buffer_reset(&payload);
1826 lttng_session_descriptor_destroy(descriptor_reply);
1827 return ret_code;
1828 }
1829
1830 /*
1831 * Create a new session using name and url for destination.
1832 *
1833 * Returns LTTNG_OK on success or a negative error code.
1834 */
1835 int lttng_create_session(const char *name, const char *url)
1836 {
1837 int ret;
1838 ssize_t size;
1839 struct lttng_uri *uris = NULL;
1840 struct lttng_session_descriptor *descriptor = NULL;
1841 enum lttng_error_code ret_code;
1842
1843 if (!name) {
1844 ret = -LTTNG_ERR_INVALID;
1845 goto end;
1846 }
1847
1848 size = uri_parse_str_urls(url, NULL, &uris);
1849 if (size < 0) {
1850 ret = -LTTNG_ERR_INVALID;
1851 goto end;
1852 }
1853 switch (size) {
1854 case 0:
1855 descriptor = lttng_session_descriptor_create(name);
1856 break;
1857 case 1:
1858 if (uris[0].dtype != LTTNG_DST_PATH) {
1859 ret = -LTTNG_ERR_INVALID;
1860 goto end;
1861 }
1862 descriptor = lttng_session_descriptor_local_create(name,
1863 uris[0].dst.path);
1864 break;
1865 case 2:
1866 descriptor = lttng_session_descriptor_network_create(name, url,
1867 NULL);
1868 break;
1869 default:
1870 ret = -LTTNG_ERR_INVALID;
1871 goto end;
1872 }
1873 if (!descriptor) {
1874 ret = -LTTNG_ERR_INVALID;
1875 goto end;
1876 }
1877 ret_code = lttng_create_session_ext(descriptor);
1878 ret = ret_code == LTTNG_OK ? 0 : -ret_code;
1879 end:
1880 lttng_session_descriptor_destroy(descriptor);
1881 free(uris);
1882 return ret;
1883 }
1884
1885 /*
1886 * Create a session exclusively used for snapshot.
1887 *
1888 * Returns LTTNG_OK on success or a negative error code.
1889 */
1890 int lttng_create_session_snapshot(const char *name, const char *snapshot_url)
1891 {
1892 int ret;
1893 enum lttng_error_code ret_code;
1894 ssize_t size;
1895 struct lttng_uri *uris = NULL;
1896 struct lttng_session_descriptor *descriptor = NULL;
1897
1898 if (!name) {
1899 ret = -LTTNG_ERR_INVALID;
1900 goto end;
1901 }
1902
1903 size = uri_parse_str_urls(snapshot_url, NULL, &uris);
1904 if (size < 0) {
1905 ret = -LTTNG_ERR_INVALID;
1906 goto end;
1907 }
1908 /*
1909 * If the user does not specify a custom subdir, use the session name.
1910 */
1911 if (size > 0 && uris[0].dtype != LTTNG_DST_PATH &&
1912 strlen(uris[0].subdir) == 0) {
1913 ret = snprintf(uris[0].subdir, sizeof(uris[0].subdir), "%s",
1914 name);
1915 if (ret < 0) {
1916 PERROR("Failed to set session name as network destination sub-directory");
1917 ret = -LTTNG_ERR_FATAL;
1918 goto end;
1919 } else if (ret >= sizeof(uris[0].subdir)) {
1920 /* Truncated output. */
1921 ret = -LTTNG_ERR_INVALID;
1922 goto end;
1923 }
1924 }
1925
1926 switch (size) {
1927 case 0:
1928 descriptor = lttng_session_descriptor_snapshot_create(name);
1929 break;
1930 case 1:
1931 if (uris[0].dtype != LTTNG_DST_PATH) {
1932 ret = -LTTNG_ERR_INVALID;
1933 goto end;
1934 }
1935 descriptor = lttng_session_descriptor_snapshot_local_create(
1936 name,
1937 uris[0].dst.path);
1938 break;
1939 case 2:
1940 descriptor = lttng_session_descriptor_snapshot_network_create(
1941 name,
1942 snapshot_url,
1943 NULL);
1944 break;
1945 default:
1946 ret = -LTTNG_ERR_INVALID;
1947 goto end;
1948 }
1949 if (!descriptor) {
1950 ret = -LTTNG_ERR_INVALID;
1951 goto end;
1952 }
1953 ret_code = lttng_create_session_ext(descriptor);
1954 ret = ret_code == LTTNG_OK ? 0 : -ret_code;
1955 end:
1956 lttng_session_descriptor_destroy(descriptor);
1957 free(uris);
1958 return ret;
1959 }
1960
1961 /*
1962 * Create a session exclusively used for live.
1963 *
1964 * Returns LTTNG_OK on success or a negative error code.
1965 */
1966 int lttng_create_session_live(const char *name, const char *url,
1967 unsigned int timer_interval)
1968 {
1969 int ret;
1970 enum lttng_error_code ret_code;
1971 struct lttng_session_descriptor *descriptor = NULL;
1972
1973 if (!name) {
1974 ret = -LTTNG_ERR_INVALID;
1975 goto end;
1976 }
1977
1978 if (url) {
1979 descriptor = lttng_session_descriptor_live_network_create(
1980 name, url, NULL, timer_interval);
1981 } else {
1982 descriptor = lttng_session_descriptor_live_create(
1983 name, timer_interval);
1984 }
1985 if (!descriptor) {
1986 ret = -LTTNG_ERR_INVALID;
1987 goto end;
1988 }
1989 ret_code = lttng_create_session_ext(descriptor);
1990 ret = ret_code == LTTNG_OK ? 0 : -ret_code;
1991 end:
1992 lttng_session_descriptor_destroy(descriptor);
1993 return ret;
1994 }
1995
1996 /*
1997 * Destroy session using name.
1998 * Returns size of returned session payload data or a negative error code.
1999 */
2000 static
2001 int _lttng_destroy_session(const char *session_name)
2002 {
2003 struct lttcomm_session_msg lsm;
2004
2005 if (session_name == NULL) {
2006 return -LTTNG_ERR_INVALID;
2007 }
2008
2009 memset(&lsm, 0, sizeof(lsm));
2010 lsm.cmd_type = LTTNG_DESTROY_SESSION;
2011
2012 lttng_ctl_copy_string(lsm.session.name, session_name,
2013 sizeof(lsm.session.name));
2014
2015 return lttng_ctl_ask_sessiond(&lsm, NULL);
2016 }
2017
2018 /*
2019 * Stop the session and wait for the data before destroying it
2020 */
2021 int lttng_destroy_session(const char *session_name)
2022 {
2023 int ret;
2024
2025 /*
2026 * Stop the tracing and wait for the data.
2027 */
2028 ret = _lttng_stop_tracing(session_name, 1);
2029 if (ret && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
2030 goto end;
2031 }
2032
2033 ret = _lttng_destroy_session(session_name);
2034 end:
2035 return ret;
2036 }
2037
2038 /*
2039 * Destroy the session without waiting for the data.
2040 */
2041 int lttng_destroy_session_no_wait(const char *session_name)
2042 {
2043 int ret;
2044
2045 /*
2046 * Stop the tracing without waiting for the data.
2047 * The session might already have been stopped, so just
2048 * skip this error.
2049 */
2050 ret = _lttng_stop_tracing(session_name, 0);
2051 if (ret && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
2052 goto end;
2053 }
2054
2055 ret = _lttng_destroy_session(session_name);
2056 end:
2057 return ret;
2058 }
2059
2060 /*
2061 * Ask the session daemon for all available sessions.
2062 * Sets the contents of the sessions array.
2063 * Returns the number of lttng_session entries in sessions;
2064 * on error, returns a negative value.
2065 */
2066 int lttng_list_sessions(struct lttng_session **out_sessions)
2067 {
2068 int ret;
2069 struct lttcomm_session_msg lsm;
2070 const size_t session_size = sizeof(struct lttng_session) +
2071 sizeof(struct lttng_session_extended);
2072 size_t session_count, i;
2073 struct lttng_session_extended *sessions_extended_begin;
2074 struct lttng_session *sessions = NULL;
2075
2076 memset(&lsm, 0, sizeof(lsm));
2077 lsm.cmd_type = LTTNG_LIST_SESSIONS;
2078 ret = lttng_ctl_ask_sessiond(&lsm, (void**) &sessions);
2079 if (ret <= 0) {
2080 goto end;
2081 }
2082 if (!sessions) {
2083 ret = -LTTNG_ERR_FATAL;
2084 goto end;
2085 }
2086
2087 if (ret % session_size) {
2088 ret = -LTTNG_ERR_UNK;
2089 free(sessions);
2090 *out_sessions = NULL;
2091 goto end;
2092 }
2093 session_count = (size_t) ret / session_size;
2094 sessions_extended_begin = (struct lttng_session_extended *)
2095 (&sessions[session_count]);
2096
2097 /* Set extended session info pointers. */
2098 for (i = 0; i < session_count; i++) {
2099 struct lttng_session *session = &sessions[i];
2100 struct lttng_session_extended *extended =
2101 &(sessions_extended_begin[i]);
2102
2103 session->extended.ptr = extended;
2104 }
2105
2106 ret = (int) session_count;
2107 *out_sessions = sessions;
2108 end:
2109 return ret;
2110 }
2111
2112 enum lttng_error_code lttng_session_get_creation_time(
2113 const struct lttng_session *session, uint64_t *creation_time)
2114 {
2115 enum lttng_error_code ret = LTTNG_OK;
2116 struct lttng_session_extended *extended;
2117
2118 if (!session || !creation_time || !session->extended.ptr) {
2119 ret = LTTNG_ERR_INVALID;
2120 goto end;
2121 }
2122
2123 extended = session->extended.ptr;
2124 if (!extended->creation_time.is_set) {
2125 /* Not created on the session daemon yet. */
2126 ret = LTTNG_ERR_SESSION_NOT_EXIST;
2127 goto end;
2128 }
2129 *creation_time = extended->creation_time.value;
2130 end:
2131 return ret;
2132 }
2133
2134 int lttng_set_session_shm_path(const char *session_name,
2135 const char *shm_path)
2136 {
2137 struct lttcomm_session_msg lsm;
2138
2139 if (session_name == NULL) {
2140 return -LTTNG_ERR_INVALID;
2141 }
2142
2143 memset(&lsm, 0, sizeof(lsm));
2144 lsm.cmd_type = LTTNG_SET_SESSION_SHM_PATH;
2145
2146 lttng_ctl_copy_string(lsm.session.name, session_name,
2147 sizeof(lsm.session.name));
2148 lttng_ctl_copy_string(lsm.u.set_shm_path.shm_path, shm_path,
2149 sizeof(lsm.u.set_shm_path.shm_path));
2150
2151 return lttng_ctl_ask_sessiond(&lsm, NULL);
2152 }
2153
2154 /*
2155 * Ask the session daemon for all available domains of a session.
2156 * Sets the contents of the domains array.
2157 * Returns the number of lttng_domain entries in domains;
2158 * on error, returns a negative value.
2159 */
2160 int lttng_list_domains(const char *session_name,
2161 struct lttng_domain **domains)
2162 {
2163 int ret;
2164 struct lttcomm_session_msg lsm;
2165
2166 if (session_name == NULL) {
2167 return -LTTNG_ERR_INVALID;
2168 }
2169
2170 memset(&lsm, 0, sizeof(lsm));
2171 lsm.cmd_type = LTTNG_LIST_DOMAINS;
2172
2173 lttng_ctl_copy_string(lsm.session.name, session_name,
2174 sizeof(lsm.session.name));
2175
2176 ret = lttng_ctl_ask_sessiond(&lsm, (void**) domains);
2177 if (ret < 0) {
2178 return ret;
2179 }
2180
2181 return ret / sizeof(struct lttng_domain);
2182 }
2183
2184 /*
2185 * Ask the session daemon for all available channels of a session.
2186 * Sets the contents of the channels array.
2187 * Returns the number of lttng_channel entries in channels;
2188 * on error, returns a negative value.
2189 */
2190 int lttng_list_channels(struct lttng_handle *handle,
2191 struct lttng_channel **channels)
2192 {
2193 int ret;
2194 size_t channel_count, i;
2195 const size_t channel_size = sizeof(struct lttng_channel) +
2196 sizeof(struct lttng_channel_extended);
2197 struct lttcomm_session_msg lsm;
2198 void *extended_at;
2199
2200 if (handle == NULL) {
2201 ret = -LTTNG_ERR_INVALID;
2202 goto end;
2203 }
2204
2205 memset(&lsm, 0, sizeof(lsm));
2206 lsm.cmd_type = LTTNG_LIST_CHANNELS;
2207 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2208 sizeof(lsm.session.name));
2209
2210 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2211
2212 ret = lttng_ctl_ask_sessiond(&lsm, (void**) channels);
2213 if (ret < 0) {
2214 goto end;
2215 }
2216
2217 if (ret % channel_size) {
2218 ret = -LTTNG_ERR_UNK;
2219 free(*channels);
2220 *channels = NULL;
2221 goto end;
2222 }
2223 channel_count = (size_t) ret / channel_size;
2224
2225 /* Set extended info pointers */
2226 extended_at = ((void *) *channels) +
2227 channel_count * sizeof(struct lttng_channel);
2228 for (i = 0; i < channel_count; i++) {
2229 struct lttng_channel *chan = &(*channels)[i];
2230
2231 chan->attr.extended.ptr = extended_at;
2232 extended_at += sizeof(struct lttng_channel_extended);
2233 }
2234
2235 ret = (int) channel_count;
2236 end:
2237 return ret;
2238 }
2239
2240 /*
2241 * Ask the session daemon for all available events of a session channel.
2242 * Sets the contents of the events array.
2243 * Returns the number of lttng_event entries in events;
2244 * on error, returns a negative value.
2245 */
2246 int lttng_list_events(struct lttng_handle *handle,
2247 const char *channel_name, struct lttng_event **events)
2248 {
2249 int ret;
2250 struct lttcomm_session_msg lsm;
2251 struct lttcomm_event_command_header *cmd_header = NULL;
2252 size_t cmd_header_len;
2253 uint32_t nb_events, i;
2254 void *comm_ext_at;
2255 char *reception_buffer = NULL;
2256 struct lttng_dynamic_buffer listing;
2257 size_t storage_req;
2258
2259 /* Safety check. An handle and channel name are mandatory */
2260 if (handle == NULL || channel_name == NULL) {
2261 return -LTTNG_ERR_INVALID;
2262 }
2263
2264 memset(&lsm, 0, sizeof(lsm));
2265 lsm.cmd_type = LTTNG_LIST_EVENTS;
2266 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2267 sizeof(lsm.session.name));
2268 lttng_ctl_copy_string(lsm.u.list.channel_name, channel_name,
2269 sizeof(lsm.u.list.channel_name));
2270 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2271
2272 ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm, NULL, 0, NULL, 0,
2273 (void **) &reception_buffer, (void **) &cmd_header,
2274 &cmd_header_len);
2275 if (ret < 0) {
2276 goto end;
2277 }
2278
2279 if (!cmd_header) {
2280 ret = -LTTNG_ERR_UNK;
2281 goto end;
2282 }
2283
2284 /* Set number of events and free command header */
2285 nb_events = cmd_header->nb_events;
2286 if (nb_events > INT_MAX) {
2287 ret = -EOVERFLOW;
2288 goto end;
2289 }
2290 free(cmd_header);
2291 cmd_header = NULL;
2292
2293 /*
2294 * The buffer that is returned must contain a "flat" version of
2295 * the events that are returned. In other words, all pointers
2296 * within an lttng_event must point to a location within the returned
2297 * buffer so that the user may free everything by simply calling free()
2298 * on the returned buffer. This is needed in order to maintain API
2299 * compatibility.
2300 *
2301 * A first pass is performed to compute the size of the buffer that
2302 * must be allocated. A second pass is then performed to setup
2303 * the returned events so that their members always point within the
2304 * buffer.
2305 *
2306 * The layout of the returned buffer is as follows:
2307 * - struct lttng_event[nb_events],
2308 * - nb_events times the following:
2309 * - struct lttng_event_extended,
2310 * - flattened version of userspace_probe_location
2311 * - filter_expression
2312 * - exclusions
2313 * - padding to align to 64-bits
2314 */
2315 comm_ext_at = reception_buffer +
2316 (nb_events * sizeof(struct lttng_event));
2317 storage_req = nb_events * sizeof(struct lttng_event);
2318
2319 for (i = 0; i < nb_events; i++) {
2320 struct lttcomm_event_extended_header *ext_comm =
2321 (struct lttcomm_event_extended_header *) comm_ext_at;
2322 int probe_storage_req = 0;
2323
2324 comm_ext_at += sizeof(*ext_comm);
2325 comm_ext_at += ext_comm->filter_len;
2326 comm_ext_at +=
2327 ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
2328
2329 if (ext_comm->userspace_probe_location_len) {
2330 struct lttng_userspace_probe_location *probe_location = NULL;
2331 struct lttng_buffer_view probe_location_view;
2332
2333 probe_location_view = lttng_buffer_view_init(
2334 comm_ext_at, 0,
2335 ext_comm->userspace_probe_location_len);
2336
2337 /*
2338 * Create a temporary userspace probe location to
2339 * determine the size needed by a "flattened" version
2340 * of that same probe location.
2341 */
2342 ret = lttng_userspace_probe_location_create_from_buffer(
2343 &probe_location_view, &probe_location);
2344 if (ret < 0) {
2345 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2346 goto end;
2347 }
2348
2349 ret = lttng_userspace_probe_location_flatten(
2350 probe_location, NULL);
2351 lttng_userspace_probe_location_destroy(probe_location);
2352 if (ret < 0) {
2353 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2354 goto end;
2355 }
2356
2357 probe_storage_req = ret;
2358 comm_ext_at += ext_comm->userspace_probe_location_len;
2359 }
2360
2361 storage_req += sizeof(struct lttng_event_extended);
2362 storage_req += ext_comm->filter_len;
2363 storage_req += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
2364 /* Padding to ensure the flat probe is aligned. */
2365 storage_req = ALIGN_TO(storage_req, sizeof(uint64_t));
2366 storage_req += probe_storage_req;
2367 }
2368
2369 lttng_dynamic_buffer_init(&listing);
2370 /*
2371 * We must ensure that "listing" is never resized so as to preserve
2372 * the validity of the flattened objects.
2373 */
2374 ret = lttng_dynamic_buffer_set_capacity(&listing, storage_req);
2375 if (ret) {
2376 ret = -LTTNG_ERR_NOMEM;
2377 goto end;
2378 }
2379
2380 ret = lttng_dynamic_buffer_append(&listing, reception_buffer,
2381 nb_events * sizeof(struct lttng_event));
2382 if (ret) {
2383 ret = -LTTNG_ERR_NOMEM;
2384 goto free_dynamic_buffer;
2385 }
2386
2387 comm_ext_at = reception_buffer +
2388 (nb_events * sizeof(struct lttng_event));
2389 for (i = 0; i < nb_events; i++) {
2390 struct lttng_event *event = (struct lttng_event *)
2391 (listing.data + (sizeof(struct lttng_event) * i));
2392 struct lttcomm_event_extended_header *ext_comm =
2393 (struct lttcomm_event_extended_header *) comm_ext_at;
2394 struct lttng_event_extended *event_extended =
2395 (struct lttng_event_extended *)
2396 (listing.data + listing.size);
2397
2398 /* Insert struct lttng_event_extended. */
2399 ret = lttng_dynamic_buffer_set_size(&listing,
2400 listing.size + sizeof(*event_extended));
2401 if (ret) {
2402 ret = -LTTNG_ERR_NOMEM;
2403 goto free_dynamic_buffer;
2404 }
2405 event->extended.ptr = event_extended;
2406
2407 comm_ext_at += sizeof(*ext_comm);
2408
2409 /* Insert filter expression. */
2410 if (ext_comm->filter_len) {
2411 event_extended->filter_expression = listing.data +
2412 listing.size;
2413 ret = lttng_dynamic_buffer_append(&listing, comm_ext_at,
2414 ext_comm->filter_len);
2415 if (ret) {
2416 ret = -LTTNG_ERR_NOMEM;
2417 goto free_dynamic_buffer;
2418 }
2419 comm_ext_at += ext_comm->filter_len;
2420 }
2421
2422 /* Insert exclusions. */
2423 if (ext_comm->nb_exclusions) {
2424 event_extended->exclusions.count =
2425 ext_comm->nb_exclusions;
2426 event_extended->exclusions.strings =
2427 listing.data + listing.size;
2428
2429 ret = lttng_dynamic_buffer_append(&listing,
2430 comm_ext_at,
2431 ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN);
2432 if (ret) {
2433 ret = -LTTNG_ERR_NOMEM;
2434 goto free_dynamic_buffer;
2435 }
2436 comm_ext_at += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
2437 }
2438
2439 /* Insert padding to align to 64-bits. */
2440 ret = lttng_dynamic_buffer_set_size(&listing,
2441 ALIGN_TO(listing.size, sizeof(uint64_t)));
2442 if (ret) {
2443 ret = -LTTNG_ERR_NOMEM;
2444 goto free_dynamic_buffer;
2445 }
2446
2447 /* Insert flattened userspace probe location. */
2448 if (ext_comm->userspace_probe_location_len) {
2449 struct lttng_userspace_probe_location *probe_location = NULL;
2450 struct lttng_buffer_view probe_location_view;
2451
2452 probe_location_view = lttng_buffer_view_init(
2453 comm_ext_at, 0,
2454 ext_comm->userspace_probe_location_len);
2455
2456 ret = lttng_userspace_probe_location_create_from_buffer(
2457 &probe_location_view, &probe_location);
2458 if (ret < 0) {
2459 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2460 goto free_dynamic_buffer;
2461 }
2462
2463 event_extended->probe_location = (struct lttng_userspace_probe_location *)
2464 (listing.data + listing.size);
2465 ret = lttng_userspace_probe_location_flatten(
2466 probe_location, &listing);
2467 lttng_userspace_probe_location_destroy(probe_location);
2468 if (ret < 0) {
2469 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2470 goto free_dynamic_buffer;
2471 }
2472
2473 comm_ext_at += ext_comm->userspace_probe_location_len;
2474 }
2475 }
2476
2477 /* Don't reset listing buffer as we return its content. */
2478 *events = (struct lttng_event *) listing.data;
2479 lttng_dynamic_buffer_init(&listing);
2480 ret = (int) nb_events;
2481 free_dynamic_buffer:
2482 lttng_dynamic_buffer_reset(&listing);
2483 end:
2484 free(cmd_header);
2485 free(reception_buffer);
2486 return ret;
2487 }
2488
2489 /*
2490 * Sets the tracing_group variable with name.
2491 * This function allocates memory pointed to by tracing_group.
2492 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
2493 */
2494 int lttng_set_tracing_group(const char *name)
2495 {
2496 if (name == NULL) {
2497 return -LTTNG_ERR_INVALID;
2498 }
2499
2500 if (asprintf(&tracing_group, "%s", name) < 0) {
2501 return -LTTNG_ERR_FATAL;
2502 }
2503
2504 return 0;
2505 }
2506
2507 int lttng_calibrate(struct lttng_handle *handle,
2508 struct lttng_calibrate *calibrate)
2509 {
2510 /*
2511 * This command was removed in LTTng 2.9.
2512 */
2513 return -LTTNG_ERR_UND;
2514 }
2515
2516 /*
2517 * Set default channel attributes.
2518 * If either or both of the arguments are null, attr content is zeroe'd.
2519 */
2520 void lttng_channel_set_default_attr(struct lttng_domain *domain,
2521 struct lttng_channel_attr *attr)
2522 {
2523 struct lttng_channel_extended *extended;
2524
2525 /* Safety check */
2526 if (attr == NULL || domain == NULL) {
2527 return;
2528 }
2529
2530 extended = (struct lttng_channel_extended *) attr->extended.ptr;
2531 memset(attr, 0, sizeof(struct lttng_channel_attr));
2532
2533 /* Same for all domains. */
2534 attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
2535 attr->tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
2536 attr->tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT;
2537
2538 switch (domain->type) {
2539 case LTTNG_DOMAIN_KERNEL:
2540 attr->switch_timer_interval =
2541 DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
2542 attr->read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
2543 attr->subbuf_size = default_get_kernel_channel_subbuf_size();
2544 attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
2545 attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
2546 if (extended) {
2547 extended->monitor_timer_interval =
2548 DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER;
2549 extended->blocking_timeout =
2550 DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT;
2551 }
2552 break;
2553 case LTTNG_DOMAIN_UST:
2554 switch (domain->buf_type) {
2555 case LTTNG_BUFFER_PER_UID:
2556 attr->subbuf_size = default_get_ust_uid_channel_subbuf_size();
2557 attr->num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM;
2558 attr->output = DEFAULT_UST_UID_CHANNEL_OUTPUT;
2559 attr->switch_timer_interval =
2560 DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER;
2561 attr->read_timer_interval =
2562 DEFAULT_UST_UID_CHANNEL_READ_TIMER;
2563 if (extended) {
2564 extended->monitor_timer_interval =
2565 DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER;
2566 extended->blocking_timeout =
2567 DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT;
2568 }
2569 break;
2570 case LTTNG_BUFFER_PER_PID:
2571 default:
2572 attr->subbuf_size = default_get_ust_pid_channel_subbuf_size();
2573 attr->num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM;
2574 attr->output = DEFAULT_UST_PID_CHANNEL_OUTPUT;
2575 attr->switch_timer_interval =
2576 DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER;
2577 attr->read_timer_interval =
2578 DEFAULT_UST_PID_CHANNEL_READ_TIMER;
2579 if (extended) {
2580 extended->monitor_timer_interval =
2581 DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER;
2582 extended->blocking_timeout =
2583 DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT;
2584 }
2585 break;
2586 }
2587 default:
2588 /* Default behavior: leave set to 0. */
2589 break;
2590 }
2591
2592 attr->extended.ptr = extended;
2593 }
2594
2595 int lttng_channel_get_discarded_event_count(struct lttng_channel *channel,
2596 uint64_t *discarded_events)
2597 {
2598 int ret = 0;
2599 struct lttng_channel_extended *chan_ext;
2600
2601 if (!channel || !discarded_events) {
2602 ret = -LTTNG_ERR_INVALID;
2603 goto end;
2604 }
2605
2606 chan_ext = channel->attr.extended.ptr;
2607 if (!chan_ext) {
2608 /*
2609 * This can happen since the lttng_channel structure is
2610 * used for other tasks where this pointer is never set.
2611 */
2612 *discarded_events = 0;
2613 goto end;
2614 }
2615
2616 *discarded_events = chan_ext->discarded_events;
2617 end:
2618 return ret;
2619 }
2620
2621 int lttng_channel_get_lost_packet_count(struct lttng_channel *channel,
2622 uint64_t *lost_packets)
2623 {
2624 int ret = 0;
2625 struct lttng_channel_extended *chan_ext;
2626
2627 if (!channel || !lost_packets) {
2628 ret = -LTTNG_ERR_INVALID;
2629 goto end;
2630 }
2631
2632 chan_ext = channel->attr.extended.ptr;
2633 if (!chan_ext) {
2634 /*
2635 * This can happen since the lttng_channel structure is
2636 * used for other tasks where this pointer is never set.
2637 */
2638 *lost_packets = 0;
2639 goto end;
2640 }
2641
2642 *lost_packets = chan_ext->lost_packets;
2643 end:
2644 return ret;
2645 }
2646
2647 int lttng_channel_get_monitor_timer_interval(struct lttng_channel *chan,
2648 uint64_t *monitor_timer_interval)
2649 {
2650 int ret = 0;
2651
2652 if (!chan || !monitor_timer_interval) {
2653 ret = -LTTNG_ERR_INVALID;
2654 goto end;
2655 }
2656
2657 if (!chan->attr.extended.ptr) {
2658 ret = -LTTNG_ERR_INVALID;
2659 goto end;
2660 }
2661
2662 *monitor_timer_interval = ((struct lttng_channel_extended *)
2663 chan->attr.extended.ptr)->monitor_timer_interval;
2664 end:
2665 return ret;
2666 }
2667
2668 int lttng_channel_set_monitor_timer_interval(struct lttng_channel *chan,
2669 uint64_t monitor_timer_interval)
2670 {
2671 int ret = 0;
2672
2673 if (!chan || !chan->attr.extended.ptr) {
2674 ret = -LTTNG_ERR_INVALID;
2675 goto end;
2676 }
2677
2678 ((struct lttng_channel_extended *)
2679 chan->attr.extended.ptr)->monitor_timer_interval =
2680 monitor_timer_interval;
2681 end:
2682 return ret;
2683 }
2684
2685 int lttng_channel_get_blocking_timeout(struct lttng_channel *chan,
2686 int64_t *blocking_timeout)
2687 {
2688 int ret = 0;
2689
2690 if (!chan || !blocking_timeout) {
2691 ret = -LTTNG_ERR_INVALID;
2692 goto end;
2693 }
2694
2695 if (!chan->attr.extended.ptr) {
2696 ret = -LTTNG_ERR_INVALID;
2697 goto end;
2698 }
2699
2700 *blocking_timeout = ((struct lttng_channel_extended *)
2701 chan->attr.extended.ptr)->blocking_timeout;
2702 end:
2703 return ret;
2704 }
2705
2706 int lttng_channel_set_blocking_timeout(struct lttng_channel *chan,
2707 int64_t blocking_timeout)
2708 {
2709 int ret = 0;
2710 int64_t msec_timeout;
2711
2712 if (!chan || !chan->attr.extended.ptr) {
2713 ret = -LTTNG_ERR_INVALID;
2714 goto end;
2715 }
2716
2717 if (blocking_timeout < 0 && blocking_timeout != -1) {
2718 ret = -LTTNG_ERR_INVALID;
2719 goto end;
2720 }
2721
2722 /*
2723 * LTTng-ust's use of poll() to implement this timeout mechanism forces
2724 * us to accept a narrower range of values (msecs expressed as a signed
2725 * 32-bit integer).
2726 */
2727 msec_timeout = blocking_timeout / 1000;
2728 if (msec_timeout != (int32_t) msec_timeout) {
2729 ret = -LTTNG_ERR_INVALID;
2730 goto end;
2731 }
2732
2733 ((struct lttng_channel_extended *)
2734 chan->attr.extended.ptr)->blocking_timeout =
2735 blocking_timeout;
2736 end:
2737 return ret;
2738 }
2739
2740 /*
2741 * Check if session daemon is alive.
2742 *
2743 * Return 1 if alive or 0 if not.
2744 * On error returns a negative value.
2745 */
2746 int lttng_session_daemon_alive(void)
2747 {
2748 int ret;
2749
2750 ret = set_session_daemon_path();
2751 if (ret < 0) {
2752 /* Error. */
2753 return ret;
2754 }
2755
2756 if (*sessiond_sock_path == '\0') {
2757 /*
2758 * No socket path set. Weird error which means the constructor
2759 * was not called.
2760 */
2761 assert(0);
2762 }
2763
2764 ret = try_connect_sessiond(sessiond_sock_path);
2765 if (ret < 0) {
2766 /* Not alive. */
2767 return 0;
2768 }
2769
2770 /* Is alive. */
2771 return 1;
2772 }
2773
2774 /*
2775 * Set URL for a consumer for a session and domain.
2776 *
2777 * Return 0 on success, else a negative value.
2778 */
2779 int lttng_set_consumer_url(struct lttng_handle *handle,
2780 const char *control_url, const char *data_url)
2781 {
2782 int ret;
2783 ssize_t size;
2784 struct lttcomm_session_msg lsm;
2785 struct lttng_uri *uris = NULL;
2786
2787 if (handle == NULL || (control_url == NULL && data_url == NULL)) {
2788 return -LTTNG_ERR_INVALID;
2789 }
2790
2791 memset(&lsm, 0, sizeof(lsm));
2792
2793 lsm.cmd_type = LTTNG_SET_CONSUMER_URI;
2794
2795 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2796 sizeof(lsm.session.name));
2797 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2798
2799 size = uri_parse_str_urls(control_url, data_url, &uris);
2800 if (size < 0) {
2801 return -LTTNG_ERR_INVALID;
2802 }
2803
2804 lsm.u.uri.size = size;
2805
2806 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, uris,
2807 sizeof(struct lttng_uri) * size, NULL);
2808
2809 free(uris);
2810 return ret;
2811 }
2812
2813 /*
2814 * [OBSOLETE]
2815 */
2816 int lttng_enable_consumer(struct lttng_handle *handle)
2817 {
2818 return -ENOSYS;
2819 }
2820
2821 /*
2822 * [OBSOLETE]
2823 */
2824 int lttng_disable_consumer(struct lttng_handle *handle)
2825 {
2826 return -ENOSYS;
2827 }
2828
2829 /*
2830 * [OBSOLETE]
2831 */
2832 int _lttng_create_session_ext(const char *name, const char *url,
2833 const char *datetime)
2834 {
2835 return -ENOSYS;
2836 }
2837
2838 /*
2839 * For a given session name, this call checks if the data is ready to be read
2840 * or is still being extracted by the consumer(s) hence not ready to be used by
2841 * any readers.
2842 */
2843 int lttng_data_pending(const char *session_name)
2844 {
2845 int ret;
2846 struct lttcomm_session_msg lsm;
2847 uint8_t *pending = NULL;
2848
2849 if (session_name == NULL) {
2850 return -LTTNG_ERR_INVALID;
2851 }
2852
2853 memset(&lsm, 0, sizeof(lsm));
2854 lsm.cmd_type = LTTNG_DATA_PENDING;
2855
2856 lttng_ctl_copy_string(lsm.session.name, session_name,
2857 sizeof(lsm.session.name));
2858
2859 ret = lttng_ctl_ask_sessiond(&lsm, (void **) &pending);
2860 if (ret < 0) {
2861 goto end;
2862 } else if (ret != 1) {
2863 /* Unexpected payload size */
2864 ret = -LTTNG_ERR_INVALID;
2865 goto end;
2866 }
2867
2868 ret = (int) *pending;
2869 end:
2870 free(pending);
2871 return ret;
2872 }
2873
2874 /*
2875 * List PIDs in the tracker.
2876 *
2877 * enabled is set to whether the PID tracker is enabled.
2878 * pids is set to an allocated array of PIDs currently tracked. On
2879 * success, pids must be freed by the caller.
2880 * nr_pids is set to the number of entries contained by the pids array.
2881 *
2882 * Returns 0 on success, else a negative LTTng error code.
2883 */
2884 int lttng_list_tracker_pids(struct lttng_handle *handle,
2885 int *_enabled, int32_t **_pids, size_t *_nr_pids)
2886 {
2887 int ret;
2888 int enabled = 1;
2889 struct lttcomm_session_msg lsm;
2890 size_t nr_pids;
2891 int32_t *pids = NULL;
2892
2893 if (handle == NULL) {
2894 return -LTTNG_ERR_INVALID;
2895 }
2896
2897 memset(&lsm, 0, sizeof(lsm));
2898 lsm.cmd_type = LTTNG_LIST_TRACKER_PIDS;
2899 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2900 sizeof(lsm.session.name));
2901 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2902
2903 ret = lttng_ctl_ask_sessiond(&lsm, (void **) &pids);
2904 if (ret < 0) {
2905 return ret;
2906 }
2907 nr_pids = ret / sizeof(int32_t);
2908 if (nr_pids > 0 && !pids) {
2909 return -LTTNG_ERR_UNK;
2910 }
2911 if (nr_pids == 1 && pids[0] == -1) {
2912 free(pids);
2913 pids = NULL;
2914 enabled = 0;
2915 nr_pids = 0;
2916 }
2917 *_enabled = enabled;
2918 *_pids = pids;
2919 *_nr_pids = nr_pids;
2920 return 0;
2921 }
2922
2923 /*
2924 * Regenerate the metadata for a session.
2925 * Return 0 on success, a negative error code on error.
2926 */
2927 int lttng_regenerate_metadata(const char *session_name)
2928 {
2929 int ret;
2930 struct lttcomm_session_msg lsm;
2931
2932 if (!session_name) {
2933 ret = -LTTNG_ERR_INVALID;
2934 goto end;
2935 }
2936
2937 memset(&lsm, 0, sizeof(lsm));
2938 lsm.cmd_type = LTTNG_REGENERATE_METADATA;
2939
2940 lttng_ctl_copy_string(lsm.session.name, session_name,
2941 sizeof(lsm.session.name));
2942
2943 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
2944 if (ret < 0) {
2945 goto end;
2946 }
2947
2948 ret = 0;
2949 end:
2950 return ret;
2951 }
2952
2953 /*
2954 * Deprecated, replaced by lttng_regenerate_metadata.
2955 */
2956 int lttng_metadata_regenerate(const char *session_name)
2957 {
2958 return lttng_regenerate_metadata(session_name);
2959 }
2960
2961 /*
2962 * Regenerate the statedump of a session.
2963 * Return 0 on success, a negative error code on error.
2964 */
2965 int lttng_regenerate_statedump(const char *session_name)
2966 {
2967 int ret;
2968 struct lttcomm_session_msg lsm;
2969
2970 if (!session_name) {
2971 ret = -LTTNG_ERR_INVALID;
2972 goto end;
2973 }
2974
2975 memset(&lsm, 0, sizeof(lsm));
2976 lsm.cmd_type = LTTNG_REGENERATE_STATEDUMP;
2977
2978 lttng_ctl_copy_string(lsm.session.name, session_name,
2979 sizeof(lsm.session.name));
2980
2981 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
2982 if (ret < 0) {
2983 goto end;
2984 }
2985
2986 ret = 0;
2987 end:
2988 return ret;
2989 }
2990
2991 int lttng_register_trigger(struct lttng_trigger *trigger)
2992 {
2993 int ret;
2994 struct lttcomm_session_msg lsm;
2995 struct lttng_dynamic_buffer buffer;
2996
2997 lttng_dynamic_buffer_init(&buffer);
2998 if (!trigger) {
2999 ret = -LTTNG_ERR_INVALID;
3000 goto end;
3001 }
3002
3003 if (!lttng_trigger_validate(trigger)) {
3004 ret = -LTTNG_ERR_INVALID_TRIGGER;
3005 goto end;
3006 }
3007
3008 ret = lttng_trigger_serialize(trigger, &buffer);
3009 if (ret < 0) {
3010 ret = -LTTNG_ERR_UNK;
3011 goto end;
3012 }
3013
3014 memset(&lsm, 0, sizeof(lsm));
3015 lsm.cmd_type = LTTNG_REGISTER_TRIGGER;
3016 lsm.u.trigger.length = (uint32_t) buffer.size;
3017 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, buffer.data,
3018 buffer.size, NULL);
3019 end:
3020 lttng_dynamic_buffer_reset(&buffer);
3021 return ret;
3022 }
3023
3024 int lttng_unregister_trigger(struct lttng_trigger *trigger)
3025 {
3026 int ret;
3027 struct lttcomm_session_msg lsm;
3028 struct lttng_dynamic_buffer buffer;
3029
3030 lttng_dynamic_buffer_init(&buffer);
3031 if (!trigger) {
3032 ret = -LTTNG_ERR_INVALID;
3033 goto end;
3034 }
3035
3036 if (!lttng_trigger_validate(trigger)) {
3037 ret = -LTTNG_ERR_INVALID_TRIGGER;
3038 goto end;
3039 }
3040
3041 ret = lttng_trigger_serialize(trigger, &buffer);
3042 if (ret < 0) {
3043 ret = -LTTNG_ERR_UNK;
3044 goto end;
3045 }
3046
3047 memset(&lsm, 0, sizeof(lsm));
3048 lsm.cmd_type = LTTNG_UNREGISTER_TRIGGER;
3049 lsm.u.trigger.length = (uint32_t) buffer.size;
3050 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, buffer.data,
3051 buffer.size, NULL);
3052 end:
3053 lttng_dynamic_buffer_reset(&buffer);
3054 return ret;
3055 }
3056
3057 /*
3058 * lib constructor.
3059 */
3060 static void __attribute__((constructor)) init(void)
3061 {
3062 /* Set default session group */
3063 lttng_set_tracing_group(DEFAULT_TRACING_GROUP);
3064 }
3065
3066 /*
3067 * lib destructor.
3068 */
3069 static void __attribute__((destructor)) lttng_ctl_exit(void)
3070 {
3071 free(tracing_group);
3072 }
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