Clean-up: Remove double buffer initialisation
[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 ret = ret == 0 ? -LTTNG_ERR_FATAL : ret;
2081 goto end;
2082 }
2083 if (!sessions) {
2084 ret = -LTTNG_ERR_FATAL;
2085 goto end;
2086 }
2087
2088 if (ret % session_size) {
2089 ret = -LTTNG_ERR_UNK;
2090 free(sessions);
2091 *out_sessions = NULL;
2092 goto end;
2093 }
2094 session_count = (size_t) ret / session_size;
2095 sessions_extended_begin = (struct lttng_session_extended *)
2096 (&sessions[session_count]);
2097
2098 /* Set extended session info pointers. */
2099 for (i = 0; i < session_count; i++) {
2100 struct lttng_session *session = &sessions[i];
2101 struct lttng_session_extended *extended =
2102 &(sessions_extended_begin[i]);
2103
2104 session->extended.ptr = extended;
2105 }
2106
2107 ret = (int) session_count;
2108 *out_sessions = sessions;
2109 end:
2110 return ret;
2111 }
2112
2113 enum lttng_error_code lttng_session_get_creation_time(
2114 const struct lttng_session *session, uint64_t *creation_time)
2115 {
2116 enum lttng_error_code ret = LTTNG_OK;
2117 struct lttng_session_extended *extended;
2118
2119 if (!session || !creation_time || !session->extended.ptr) {
2120 ret = LTTNG_ERR_INVALID;
2121 goto end;
2122 }
2123
2124 extended = session->extended.ptr;
2125 if (!extended->creation_time.is_set) {
2126 /* Not created on the session daemon yet. */
2127 ret = LTTNG_ERR_SESSION_NOT_EXIST;
2128 goto end;
2129 }
2130 *creation_time = extended->creation_time.value;
2131 end:
2132 return ret;
2133 }
2134
2135 int lttng_set_session_shm_path(const char *session_name,
2136 const char *shm_path)
2137 {
2138 struct lttcomm_session_msg lsm;
2139
2140 if (session_name == NULL) {
2141 return -LTTNG_ERR_INVALID;
2142 }
2143
2144 memset(&lsm, 0, sizeof(lsm));
2145 lsm.cmd_type = LTTNG_SET_SESSION_SHM_PATH;
2146
2147 lttng_ctl_copy_string(lsm.session.name, session_name,
2148 sizeof(lsm.session.name));
2149 lttng_ctl_copy_string(lsm.u.set_shm_path.shm_path, shm_path,
2150 sizeof(lsm.u.set_shm_path.shm_path));
2151
2152 return lttng_ctl_ask_sessiond(&lsm, NULL);
2153 }
2154
2155 /*
2156 * Ask the session daemon for all available domains of a session.
2157 * Sets the contents of the domains array.
2158 * Returns the number of lttng_domain entries in domains;
2159 * on error, returns a negative value.
2160 */
2161 int lttng_list_domains(const char *session_name,
2162 struct lttng_domain **domains)
2163 {
2164 int ret;
2165 struct lttcomm_session_msg lsm;
2166
2167 if (session_name == NULL) {
2168 return -LTTNG_ERR_INVALID;
2169 }
2170
2171 memset(&lsm, 0, sizeof(lsm));
2172 lsm.cmd_type = LTTNG_LIST_DOMAINS;
2173
2174 lttng_ctl_copy_string(lsm.session.name, session_name,
2175 sizeof(lsm.session.name));
2176
2177 ret = lttng_ctl_ask_sessiond(&lsm, (void**) domains);
2178 if (ret < 0) {
2179 return ret;
2180 }
2181
2182 return ret / sizeof(struct lttng_domain);
2183 }
2184
2185 /*
2186 * Ask the session daemon for all available channels of a session.
2187 * Sets the contents of the channels array.
2188 * Returns the number of lttng_channel entries in channels;
2189 * on error, returns a negative value.
2190 */
2191 int lttng_list_channels(struct lttng_handle *handle,
2192 struct lttng_channel **channels)
2193 {
2194 int ret;
2195 size_t channel_count, i;
2196 const size_t channel_size = sizeof(struct lttng_channel) +
2197 sizeof(struct lttng_channel_extended);
2198 struct lttcomm_session_msg lsm;
2199 void *extended_at;
2200
2201 if (handle == NULL) {
2202 ret = -LTTNG_ERR_INVALID;
2203 goto end;
2204 }
2205
2206 memset(&lsm, 0, sizeof(lsm));
2207 lsm.cmd_type = LTTNG_LIST_CHANNELS;
2208 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2209 sizeof(lsm.session.name));
2210
2211 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2212
2213 ret = lttng_ctl_ask_sessiond(&lsm, (void**) channels);
2214 if (ret < 0) {
2215 goto end;
2216 }
2217
2218 if (ret % channel_size) {
2219 ret = -LTTNG_ERR_UNK;
2220 free(*channels);
2221 *channels = NULL;
2222 goto end;
2223 }
2224 channel_count = (size_t) ret / channel_size;
2225
2226 /* Set extended info pointers */
2227 extended_at = ((void *) *channels) +
2228 channel_count * sizeof(struct lttng_channel);
2229 for (i = 0; i < channel_count; i++) {
2230 struct lttng_channel *chan = &(*channels)[i];
2231
2232 chan->attr.extended.ptr = extended_at;
2233 extended_at += sizeof(struct lttng_channel_extended);
2234 }
2235
2236 ret = (int) channel_count;
2237 end:
2238 return ret;
2239 }
2240
2241 /*
2242 * Ask the session daemon for all available events of a session channel.
2243 * Sets the contents of the events array.
2244 * Returns the number of lttng_event entries in events;
2245 * on error, returns a negative value.
2246 */
2247 int lttng_list_events(struct lttng_handle *handle,
2248 const char *channel_name, struct lttng_event **events)
2249 {
2250 int ret;
2251 struct lttcomm_session_msg lsm;
2252 struct lttcomm_event_command_header *cmd_header = NULL;
2253 size_t cmd_header_len;
2254 uint32_t nb_events, i;
2255 void *comm_ext_at;
2256 char *reception_buffer = NULL;
2257 struct lttng_dynamic_buffer listing;
2258 size_t storage_req;
2259
2260 /* Safety check. An handle and channel name are mandatory */
2261 if (handle == NULL || channel_name == NULL) {
2262 return -LTTNG_ERR_INVALID;
2263 }
2264
2265 memset(&lsm, 0, sizeof(lsm));
2266 lsm.cmd_type = LTTNG_LIST_EVENTS;
2267 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2268 sizeof(lsm.session.name));
2269 lttng_ctl_copy_string(lsm.u.list.channel_name, channel_name,
2270 sizeof(lsm.u.list.channel_name));
2271 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2272
2273 ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm, NULL, 0, NULL, 0,
2274 (void **) &reception_buffer, (void **) &cmd_header,
2275 &cmd_header_len);
2276 if (ret < 0) {
2277 goto end;
2278 }
2279
2280 if (!cmd_header) {
2281 ret = -LTTNG_ERR_UNK;
2282 goto end;
2283 }
2284
2285 /* Set number of events and free command header */
2286 nb_events = cmd_header->nb_events;
2287 if (nb_events > INT_MAX) {
2288 ret = -EOVERFLOW;
2289 goto end;
2290 }
2291 free(cmd_header);
2292 cmd_header = NULL;
2293
2294 /*
2295 * The buffer that is returned must contain a "flat" version of
2296 * the events that are returned. In other words, all pointers
2297 * within an lttng_event must point to a location within the returned
2298 * buffer so that the user may free everything by simply calling free()
2299 * on the returned buffer. This is needed in order to maintain API
2300 * compatibility.
2301 *
2302 * A first pass is performed to compute the size of the buffer that
2303 * must be allocated. A second pass is then performed to setup
2304 * the returned events so that their members always point within the
2305 * buffer.
2306 *
2307 * The layout of the returned buffer is as follows:
2308 * - struct lttng_event[nb_events],
2309 * - nb_events times the following:
2310 * - struct lttng_event_extended,
2311 * - flattened version of userspace_probe_location
2312 * - filter_expression
2313 * - exclusions
2314 * - padding to align to 64-bits
2315 */
2316 comm_ext_at = reception_buffer +
2317 (nb_events * sizeof(struct lttng_event));
2318 storage_req = nb_events * sizeof(struct lttng_event);
2319
2320 for (i = 0; i < nb_events; i++) {
2321 struct lttcomm_event_extended_header *ext_comm =
2322 (struct lttcomm_event_extended_header *) comm_ext_at;
2323 int probe_storage_req = 0;
2324
2325 comm_ext_at += sizeof(*ext_comm);
2326 comm_ext_at += ext_comm->filter_len;
2327 comm_ext_at +=
2328 ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
2329
2330 if (ext_comm->userspace_probe_location_len) {
2331 struct lttng_userspace_probe_location *probe_location = NULL;
2332 struct lttng_buffer_view probe_location_view;
2333
2334 probe_location_view = lttng_buffer_view_init(
2335 comm_ext_at, 0,
2336 ext_comm->userspace_probe_location_len);
2337
2338 /*
2339 * Create a temporary userspace probe location to
2340 * determine the size needed by a "flattened" version
2341 * of that same probe location.
2342 */
2343 ret = lttng_userspace_probe_location_create_from_buffer(
2344 &probe_location_view, &probe_location);
2345 if (ret < 0) {
2346 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2347 goto end;
2348 }
2349
2350 ret = lttng_userspace_probe_location_flatten(
2351 probe_location, NULL);
2352 lttng_userspace_probe_location_destroy(probe_location);
2353 if (ret < 0) {
2354 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2355 goto end;
2356 }
2357
2358 probe_storage_req = ret;
2359 comm_ext_at += ext_comm->userspace_probe_location_len;
2360 }
2361
2362 storage_req += sizeof(struct lttng_event_extended);
2363 storage_req += ext_comm->filter_len;
2364 storage_req += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
2365 /* Padding to ensure the flat probe is aligned. */
2366 storage_req = ALIGN_TO(storage_req, sizeof(uint64_t));
2367 storage_req += probe_storage_req;
2368 }
2369
2370 lttng_dynamic_buffer_init(&listing);
2371 /*
2372 * We must ensure that "listing" is never resized so as to preserve
2373 * the validity of the flattened objects.
2374 */
2375 ret = lttng_dynamic_buffer_set_capacity(&listing, storage_req);
2376 if (ret) {
2377 ret = -LTTNG_ERR_NOMEM;
2378 goto end;
2379 }
2380
2381 ret = lttng_dynamic_buffer_append(&listing, reception_buffer,
2382 nb_events * sizeof(struct lttng_event));
2383 if (ret) {
2384 ret = -LTTNG_ERR_NOMEM;
2385 goto free_dynamic_buffer;
2386 }
2387
2388 comm_ext_at = reception_buffer +
2389 (nb_events * sizeof(struct lttng_event));
2390 for (i = 0; i < nb_events; i++) {
2391 struct lttng_event *event = (struct lttng_event *)
2392 (listing.data + (sizeof(struct lttng_event) * i));
2393 struct lttcomm_event_extended_header *ext_comm =
2394 (struct lttcomm_event_extended_header *) comm_ext_at;
2395 struct lttng_event_extended *event_extended =
2396 (struct lttng_event_extended *)
2397 (listing.data + listing.size);
2398
2399 /* Insert struct lttng_event_extended. */
2400 ret = lttng_dynamic_buffer_set_size(&listing,
2401 listing.size + sizeof(*event_extended));
2402 if (ret) {
2403 ret = -LTTNG_ERR_NOMEM;
2404 goto free_dynamic_buffer;
2405 }
2406 event->extended.ptr = event_extended;
2407
2408 comm_ext_at += sizeof(*ext_comm);
2409
2410 /* Insert filter expression. */
2411 if (ext_comm->filter_len) {
2412 event_extended->filter_expression = listing.data +
2413 listing.size;
2414 ret = lttng_dynamic_buffer_append(&listing, comm_ext_at,
2415 ext_comm->filter_len);
2416 if (ret) {
2417 ret = -LTTNG_ERR_NOMEM;
2418 goto free_dynamic_buffer;
2419 }
2420 comm_ext_at += ext_comm->filter_len;
2421 }
2422
2423 /* Insert exclusions. */
2424 if (ext_comm->nb_exclusions) {
2425 event_extended->exclusions.count =
2426 ext_comm->nb_exclusions;
2427 event_extended->exclusions.strings =
2428 listing.data + listing.size;
2429
2430 ret = lttng_dynamic_buffer_append(&listing,
2431 comm_ext_at,
2432 ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN);
2433 if (ret) {
2434 ret = -LTTNG_ERR_NOMEM;
2435 goto free_dynamic_buffer;
2436 }
2437 comm_ext_at += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
2438 }
2439
2440 /* Insert padding to align to 64-bits. */
2441 ret = lttng_dynamic_buffer_set_size(&listing,
2442 ALIGN_TO(listing.size, sizeof(uint64_t)));
2443 if (ret) {
2444 ret = -LTTNG_ERR_NOMEM;
2445 goto free_dynamic_buffer;
2446 }
2447
2448 /* Insert flattened userspace probe location. */
2449 if (ext_comm->userspace_probe_location_len) {
2450 struct lttng_userspace_probe_location *probe_location = NULL;
2451 struct lttng_buffer_view probe_location_view;
2452
2453 probe_location_view = lttng_buffer_view_init(
2454 comm_ext_at, 0,
2455 ext_comm->userspace_probe_location_len);
2456
2457 ret = lttng_userspace_probe_location_create_from_buffer(
2458 &probe_location_view, &probe_location);
2459 if (ret < 0) {
2460 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2461 goto free_dynamic_buffer;
2462 }
2463
2464 event_extended->probe_location = (struct lttng_userspace_probe_location *)
2465 (listing.data + listing.size);
2466 ret = lttng_userspace_probe_location_flatten(
2467 probe_location, &listing);
2468 lttng_userspace_probe_location_destroy(probe_location);
2469 if (ret < 0) {
2470 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2471 goto free_dynamic_buffer;
2472 }
2473
2474 comm_ext_at += ext_comm->userspace_probe_location_len;
2475 }
2476 }
2477
2478 /* Don't reset listing buffer as we return its content. */
2479 *events = (struct lttng_event *) listing.data;
2480 lttng_dynamic_buffer_init(&listing);
2481 ret = (int) nb_events;
2482 free_dynamic_buffer:
2483 lttng_dynamic_buffer_reset(&listing);
2484 end:
2485 free(cmd_header);
2486 free(reception_buffer);
2487 return ret;
2488 }
2489
2490 /*
2491 * Sets the tracing_group variable with name.
2492 * This function allocates memory pointed to by tracing_group.
2493 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
2494 */
2495 int lttng_set_tracing_group(const char *name)
2496 {
2497 if (name == NULL) {
2498 return -LTTNG_ERR_INVALID;
2499 }
2500
2501 if (asprintf(&tracing_group, "%s", name) < 0) {
2502 return -LTTNG_ERR_FATAL;
2503 }
2504
2505 return 0;
2506 }
2507
2508 int lttng_calibrate(struct lttng_handle *handle,
2509 struct lttng_calibrate *calibrate)
2510 {
2511 /*
2512 * This command was removed in LTTng 2.9.
2513 */
2514 return -LTTNG_ERR_UND;
2515 }
2516
2517 /*
2518 * Set default channel attributes.
2519 * If either or both of the arguments are null, attr content is zeroe'd.
2520 */
2521 void lttng_channel_set_default_attr(struct lttng_domain *domain,
2522 struct lttng_channel_attr *attr)
2523 {
2524 struct lttng_channel_extended *extended;
2525
2526 /* Safety check */
2527 if (attr == NULL || domain == NULL) {
2528 return;
2529 }
2530
2531 extended = (struct lttng_channel_extended *) attr->extended.ptr;
2532 memset(attr, 0, sizeof(struct lttng_channel_attr));
2533
2534 /* Same for all domains. */
2535 attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
2536 attr->tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
2537 attr->tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT;
2538
2539 switch (domain->type) {
2540 case LTTNG_DOMAIN_KERNEL:
2541 attr->switch_timer_interval =
2542 DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
2543 attr->read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
2544 attr->subbuf_size = default_get_kernel_channel_subbuf_size();
2545 attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
2546 attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
2547 if (extended) {
2548 extended->monitor_timer_interval =
2549 DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER;
2550 extended->blocking_timeout =
2551 DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT;
2552 }
2553 break;
2554 case LTTNG_DOMAIN_UST:
2555 switch (domain->buf_type) {
2556 case LTTNG_BUFFER_PER_UID:
2557 attr->subbuf_size = default_get_ust_uid_channel_subbuf_size();
2558 attr->num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM;
2559 attr->output = DEFAULT_UST_UID_CHANNEL_OUTPUT;
2560 attr->switch_timer_interval =
2561 DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER;
2562 attr->read_timer_interval =
2563 DEFAULT_UST_UID_CHANNEL_READ_TIMER;
2564 if (extended) {
2565 extended->monitor_timer_interval =
2566 DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER;
2567 extended->blocking_timeout =
2568 DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT;
2569 }
2570 break;
2571 case LTTNG_BUFFER_PER_PID:
2572 default:
2573 attr->subbuf_size = default_get_ust_pid_channel_subbuf_size();
2574 attr->num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM;
2575 attr->output = DEFAULT_UST_PID_CHANNEL_OUTPUT;
2576 attr->switch_timer_interval =
2577 DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER;
2578 attr->read_timer_interval =
2579 DEFAULT_UST_PID_CHANNEL_READ_TIMER;
2580 if (extended) {
2581 extended->monitor_timer_interval =
2582 DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER;
2583 extended->blocking_timeout =
2584 DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT;
2585 }
2586 break;
2587 }
2588 default:
2589 /* Default behavior: leave set to 0. */
2590 break;
2591 }
2592
2593 attr->extended.ptr = extended;
2594 }
2595
2596 int lttng_channel_get_discarded_event_count(struct lttng_channel *channel,
2597 uint64_t *discarded_events)
2598 {
2599 int ret = 0;
2600 struct lttng_channel_extended *chan_ext;
2601
2602 if (!channel || !discarded_events) {
2603 ret = -LTTNG_ERR_INVALID;
2604 goto end;
2605 }
2606
2607 chan_ext = channel->attr.extended.ptr;
2608 if (!chan_ext) {
2609 /*
2610 * This can happen since the lttng_channel structure is
2611 * used for other tasks where this pointer is never set.
2612 */
2613 *discarded_events = 0;
2614 goto end;
2615 }
2616
2617 *discarded_events = chan_ext->discarded_events;
2618 end:
2619 return ret;
2620 }
2621
2622 int lttng_channel_get_lost_packet_count(struct lttng_channel *channel,
2623 uint64_t *lost_packets)
2624 {
2625 int ret = 0;
2626 struct lttng_channel_extended *chan_ext;
2627
2628 if (!channel || !lost_packets) {
2629 ret = -LTTNG_ERR_INVALID;
2630 goto end;
2631 }
2632
2633 chan_ext = channel->attr.extended.ptr;
2634 if (!chan_ext) {
2635 /*
2636 * This can happen since the lttng_channel structure is
2637 * used for other tasks where this pointer is never set.
2638 */
2639 *lost_packets = 0;
2640 goto end;
2641 }
2642
2643 *lost_packets = chan_ext->lost_packets;
2644 end:
2645 return ret;
2646 }
2647
2648 int lttng_channel_get_monitor_timer_interval(struct lttng_channel *chan,
2649 uint64_t *monitor_timer_interval)
2650 {
2651 int ret = 0;
2652
2653 if (!chan || !monitor_timer_interval) {
2654 ret = -LTTNG_ERR_INVALID;
2655 goto end;
2656 }
2657
2658 if (!chan->attr.extended.ptr) {
2659 ret = -LTTNG_ERR_INVALID;
2660 goto end;
2661 }
2662
2663 *monitor_timer_interval = ((struct lttng_channel_extended *)
2664 chan->attr.extended.ptr)->monitor_timer_interval;
2665 end:
2666 return ret;
2667 }
2668
2669 int lttng_channel_set_monitor_timer_interval(struct lttng_channel *chan,
2670 uint64_t monitor_timer_interval)
2671 {
2672 int ret = 0;
2673
2674 if (!chan || !chan->attr.extended.ptr) {
2675 ret = -LTTNG_ERR_INVALID;
2676 goto end;
2677 }
2678
2679 ((struct lttng_channel_extended *)
2680 chan->attr.extended.ptr)->monitor_timer_interval =
2681 monitor_timer_interval;
2682 end:
2683 return ret;
2684 }
2685
2686 int lttng_channel_get_blocking_timeout(struct lttng_channel *chan,
2687 int64_t *blocking_timeout)
2688 {
2689 int ret = 0;
2690
2691 if (!chan || !blocking_timeout) {
2692 ret = -LTTNG_ERR_INVALID;
2693 goto end;
2694 }
2695
2696 if (!chan->attr.extended.ptr) {
2697 ret = -LTTNG_ERR_INVALID;
2698 goto end;
2699 }
2700
2701 *blocking_timeout = ((struct lttng_channel_extended *)
2702 chan->attr.extended.ptr)->blocking_timeout;
2703 end:
2704 return ret;
2705 }
2706
2707 int lttng_channel_set_blocking_timeout(struct lttng_channel *chan,
2708 int64_t blocking_timeout)
2709 {
2710 int ret = 0;
2711 int64_t msec_timeout;
2712
2713 if (!chan || !chan->attr.extended.ptr) {
2714 ret = -LTTNG_ERR_INVALID;
2715 goto end;
2716 }
2717
2718 if (blocking_timeout < 0 && blocking_timeout != -1) {
2719 ret = -LTTNG_ERR_INVALID;
2720 goto end;
2721 }
2722
2723 /*
2724 * LTTng-ust's use of poll() to implement this timeout mechanism forces
2725 * us to accept a narrower range of values (msecs expressed as a signed
2726 * 32-bit integer).
2727 */
2728 msec_timeout = blocking_timeout / 1000;
2729 if (msec_timeout != (int32_t) msec_timeout) {
2730 ret = -LTTNG_ERR_INVALID;
2731 goto end;
2732 }
2733
2734 ((struct lttng_channel_extended *)
2735 chan->attr.extended.ptr)->blocking_timeout =
2736 blocking_timeout;
2737 end:
2738 return ret;
2739 }
2740
2741 /*
2742 * Check if session daemon is alive.
2743 *
2744 * Return 1 if alive or 0 if not.
2745 * On error returns a negative value.
2746 */
2747 int lttng_session_daemon_alive(void)
2748 {
2749 int ret;
2750
2751 ret = set_session_daemon_path();
2752 if (ret < 0) {
2753 /* Error. */
2754 return ret;
2755 }
2756
2757 if (*sessiond_sock_path == '\0') {
2758 /*
2759 * No socket path set. Weird error which means the constructor
2760 * was not called.
2761 */
2762 assert(0);
2763 }
2764
2765 ret = try_connect_sessiond(sessiond_sock_path);
2766 if (ret < 0) {
2767 /* Not alive. */
2768 return 0;
2769 }
2770
2771 /* Is alive. */
2772 return 1;
2773 }
2774
2775 /*
2776 * Set URL for a consumer for a session and domain.
2777 *
2778 * Return 0 on success, else a negative value.
2779 */
2780 int lttng_set_consumer_url(struct lttng_handle *handle,
2781 const char *control_url, const char *data_url)
2782 {
2783 int ret;
2784 ssize_t size;
2785 struct lttcomm_session_msg lsm;
2786 struct lttng_uri *uris = NULL;
2787
2788 if (handle == NULL || (control_url == NULL && data_url == NULL)) {
2789 return -LTTNG_ERR_INVALID;
2790 }
2791
2792 memset(&lsm, 0, sizeof(lsm));
2793
2794 lsm.cmd_type = LTTNG_SET_CONSUMER_URI;
2795
2796 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2797 sizeof(lsm.session.name));
2798 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2799
2800 size = uri_parse_str_urls(control_url, data_url, &uris);
2801 if (size < 0) {
2802 return -LTTNG_ERR_INVALID;
2803 }
2804
2805 lsm.u.uri.size = size;
2806
2807 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, uris,
2808 sizeof(struct lttng_uri) * size, NULL);
2809
2810 free(uris);
2811 return ret;
2812 }
2813
2814 /*
2815 * [OBSOLETE]
2816 */
2817 int lttng_enable_consumer(struct lttng_handle *handle)
2818 {
2819 return -ENOSYS;
2820 }
2821
2822 /*
2823 * [OBSOLETE]
2824 */
2825 int lttng_disable_consumer(struct lttng_handle *handle)
2826 {
2827 return -ENOSYS;
2828 }
2829
2830 /*
2831 * [OBSOLETE]
2832 */
2833 int _lttng_create_session_ext(const char *name, const char *url,
2834 const char *datetime)
2835 {
2836 return -ENOSYS;
2837 }
2838
2839 /*
2840 * For a given session name, this call checks if the data is ready to be read
2841 * or is still being extracted by the consumer(s) hence not ready to be used by
2842 * any readers.
2843 */
2844 int lttng_data_pending(const char *session_name)
2845 {
2846 int ret;
2847 struct lttcomm_session_msg lsm;
2848 uint8_t *pending = NULL;
2849
2850 if (session_name == NULL) {
2851 return -LTTNG_ERR_INVALID;
2852 }
2853
2854 memset(&lsm, 0, sizeof(lsm));
2855 lsm.cmd_type = LTTNG_DATA_PENDING;
2856
2857 lttng_ctl_copy_string(lsm.session.name, session_name,
2858 sizeof(lsm.session.name));
2859
2860 ret = lttng_ctl_ask_sessiond(&lsm, (void **) &pending);
2861 if (ret < 0) {
2862 goto end;
2863 } else if (ret != 1) {
2864 /* Unexpected payload size */
2865 ret = -LTTNG_ERR_INVALID;
2866 goto end;
2867 }
2868
2869 ret = (int) *pending;
2870 end:
2871 free(pending);
2872 return ret;
2873 }
2874
2875 /*
2876 * List PIDs in the tracker.
2877 *
2878 * enabled is set to whether the PID tracker is enabled.
2879 * pids is set to an allocated array of PIDs currently tracked. On
2880 * success, pids must be freed by the caller.
2881 * nr_pids is set to the number of entries contained by the pids array.
2882 *
2883 * Returns 0 on success, else a negative LTTng error code.
2884 */
2885 int lttng_list_tracker_pids(struct lttng_handle *handle,
2886 int *_enabled, int32_t **_pids, size_t *_nr_pids)
2887 {
2888 int ret;
2889 int enabled = 1;
2890 struct lttcomm_session_msg lsm;
2891 size_t nr_pids;
2892 int32_t *pids = NULL;
2893
2894 if (handle == NULL) {
2895 return -LTTNG_ERR_INVALID;
2896 }
2897
2898 memset(&lsm, 0, sizeof(lsm));
2899 lsm.cmd_type = LTTNG_LIST_TRACKER_PIDS;
2900 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
2901 sizeof(lsm.session.name));
2902 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
2903
2904 ret = lttng_ctl_ask_sessiond(&lsm, (void **) &pids);
2905 if (ret < 0) {
2906 return ret;
2907 }
2908 nr_pids = ret / sizeof(int32_t);
2909 if (nr_pids > 0 && !pids) {
2910 return -LTTNG_ERR_UNK;
2911 }
2912 if (nr_pids == 1 && pids[0] == -1) {
2913 free(pids);
2914 pids = NULL;
2915 enabled = 0;
2916 nr_pids = 0;
2917 }
2918 *_enabled = enabled;
2919 *_pids = pids;
2920 *_nr_pids = nr_pids;
2921 return 0;
2922 }
2923
2924 /*
2925 * Regenerate the metadata for a session.
2926 * Return 0 on success, a negative error code on error.
2927 */
2928 int lttng_regenerate_metadata(const char *session_name)
2929 {
2930 int ret;
2931 struct lttcomm_session_msg lsm;
2932
2933 if (!session_name) {
2934 ret = -LTTNG_ERR_INVALID;
2935 goto end;
2936 }
2937
2938 memset(&lsm, 0, sizeof(lsm));
2939 lsm.cmd_type = LTTNG_REGENERATE_METADATA;
2940
2941 lttng_ctl_copy_string(lsm.session.name, session_name,
2942 sizeof(lsm.session.name));
2943
2944 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
2945 if (ret < 0) {
2946 goto end;
2947 }
2948
2949 ret = 0;
2950 end:
2951 return ret;
2952 }
2953
2954 /*
2955 * Deprecated, replaced by lttng_regenerate_metadata.
2956 */
2957 int lttng_metadata_regenerate(const char *session_name)
2958 {
2959 return lttng_regenerate_metadata(session_name);
2960 }
2961
2962 /*
2963 * Regenerate the statedump of a session.
2964 * Return 0 on success, a negative error code on error.
2965 */
2966 int lttng_regenerate_statedump(const char *session_name)
2967 {
2968 int ret;
2969 struct lttcomm_session_msg lsm;
2970
2971 if (!session_name) {
2972 ret = -LTTNG_ERR_INVALID;
2973 goto end;
2974 }
2975
2976 memset(&lsm, 0, sizeof(lsm));
2977 lsm.cmd_type = LTTNG_REGENERATE_STATEDUMP;
2978
2979 lttng_ctl_copy_string(lsm.session.name, session_name,
2980 sizeof(lsm.session.name));
2981
2982 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
2983 if (ret < 0) {
2984 goto end;
2985 }
2986
2987 ret = 0;
2988 end:
2989 return ret;
2990 }
2991
2992 int lttng_register_trigger(struct lttng_trigger *trigger)
2993 {
2994 int ret;
2995 struct lttcomm_session_msg lsm;
2996 struct lttng_dynamic_buffer buffer;
2997
2998 lttng_dynamic_buffer_init(&buffer);
2999 if (!trigger) {
3000 ret = -LTTNG_ERR_INVALID;
3001 goto end;
3002 }
3003
3004 if (!lttng_trigger_validate(trigger)) {
3005 ret = -LTTNG_ERR_INVALID_TRIGGER;
3006 goto end;
3007 }
3008
3009 ret = lttng_trigger_serialize(trigger, &buffer);
3010 if (ret < 0) {
3011 ret = -LTTNG_ERR_UNK;
3012 goto end;
3013 }
3014
3015 memset(&lsm, 0, sizeof(lsm));
3016 lsm.cmd_type = LTTNG_REGISTER_TRIGGER;
3017 lsm.u.trigger.length = (uint32_t) buffer.size;
3018 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, buffer.data,
3019 buffer.size, NULL);
3020 end:
3021 lttng_dynamic_buffer_reset(&buffer);
3022 return ret;
3023 }
3024
3025 int lttng_unregister_trigger(struct lttng_trigger *trigger)
3026 {
3027 int ret;
3028 struct lttcomm_session_msg lsm;
3029 struct lttng_dynamic_buffer buffer;
3030
3031 lttng_dynamic_buffer_init(&buffer);
3032 if (!trigger) {
3033 ret = -LTTNG_ERR_INVALID;
3034 goto end;
3035 }
3036
3037 if (!lttng_trigger_validate(trigger)) {
3038 ret = -LTTNG_ERR_INVALID_TRIGGER;
3039 goto end;
3040 }
3041
3042 ret = lttng_trigger_serialize(trigger, &buffer);
3043 if (ret < 0) {
3044 ret = -LTTNG_ERR_UNK;
3045 goto end;
3046 }
3047
3048 memset(&lsm, 0, sizeof(lsm));
3049 lsm.cmd_type = LTTNG_UNREGISTER_TRIGGER;
3050 lsm.u.trigger.length = (uint32_t) buffer.size;
3051 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, buffer.data,
3052 buffer.size, NULL);
3053 end:
3054 lttng_dynamic_buffer_reset(&buffer);
3055 return ret;
3056 }
3057
3058 /*
3059 * lib constructor.
3060 */
3061 static void __attribute__((constructor)) init(void)
3062 {
3063 /* Set default session group */
3064 lttng_set_tracing_group(DEFAULT_TRACING_GROUP);
3065 }
3066
3067 /*
3068 * lib destructor.
3069 */
3070 static void __attribute__((destructor)) lttng_ctl_exit(void)
3071 {
3072 free(tracing_group);
3073 }
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