CLI: add-trigger: add --capture option to `on-event` condition
[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 * SPDX-License-Identifier: LGPL-2.1-only
10 *
11 */
12
13 #define _LGPL_SOURCE
14 #include <assert.h>
15 #include <grp.h>
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <string.h>
19 #include <unistd.h>
20
21 #include <common/common.h>
22 #include <common/compat/errno.h>
23 #include <common/compat/string.h>
24 #include <common/defaults.h>
25 #include <common/dynamic-buffer.h>
26 #include <common/dynamic-array.h>
27 #include <common/payload.h>
28 #include <common/payload-view.h>
29 #include <common/sessiond-comm/sessiond-comm.h>
30 #include <common/tracker.h>
31 #include <common/unix.h>
32 #include <common/uri.h>
33 #include <common/utils.h>
34 #include <lttng/channel-internal.h>
35 #include <lttng/destruction-handle.h>
36 #include <lttng/endpoint.h>
37 #include <lttng/event-internal.h>
38 #include <lttng/health-internal.h>
39 #include <lttng/lttng.h>
40 #include <lttng/session-descriptor-internal.h>
41 #include <lttng/session-internal.h>
42 #include <lttng/trigger/trigger-internal.h>
43 #include <lttng/userspace-probe-internal.h>
44 #include <lttng/lttng-error.h>
45
46 #include <common/filter/filter-ast.h>
47 #include <common/filter/filter-parser.h>
48 #include <common/filter/filter-bytecode.h>
49 #include <common/filter/memstream.h>
50 #include "lttng-ctl-helper.h"
51
52 #define COPY_DOMAIN_PACKED(dst, src) \
53 do { \
54 struct lttng_domain _tmp_domain; \
55 \
56 lttng_ctl_copy_lttng_domain(&_tmp_domain, &src); \
57 dst = _tmp_domain; \
58 } while (0)
59
60 /* Socket to session daemon for communication */
61 static int sessiond_socket = -1;
62 static char sessiond_sock_path[PATH_MAX];
63
64 /* Variables */
65 static char *tracing_group;
66 static int connected;
67
68 /* Global */
69
70 /*
71 * Those two variables are used by error.h to silent or control the verbosity of
72 * error message. They are global to the library so application linking with it
73 * are able to compile correctly and also control verbosity of the library.
74 */
75 int lttng_opt_quiet;
76 int lttng_opt_verbose;
77 int lttng_opt_mi;
78
79 /*
80 * Copy domain to lttcomm_session_msg domain.
81 *
82 * If domain is unknown, default domain will be the kernel.
83 */
84 LTTNG_HIDDEN
85 void lttng_ctl_copy_lttng_domain(struct lttng_domain *dst,
86 struct lttng_domain *src)
87 {
88 if (src && dst) {
89 switch (src->type) {
90 case LTTNG_DOMAIN_KERNEL:
91 case LTTNG_DOMAIN_UST:
92 case LTTNG_DOMAIN_JUL:
93 case LTTNG_DOMAIN_LOG4J:
94 case LTTNG_DOMAIN_PYTHON:
95 memcpy(dst, src, sizeof(struct lttng_domain));
96 break;
97 default:
98 memset(dst, 0, sizeof(struct lttng_domain));
99 break;
100 }
101 }
102 }
103
104 /*
105 * Send lttcomm_session_msg to the session daemon.
106 *
107 * On success, returns the number of bytes sent (>=0)
108 * On error, returns -1
109 */
110 static int send_session_msg(struct lttcomm_session_msg *lsm)
111 {
112 int ret;
113
114 if (!connected) {
115 ret = -LTTNG_ERR_NO_SESSIOND;
116 goto end;
117 }
118
119 DBG("LSM cmd type: '%s' (%d)", lttcomm_sessiond_command_str(lsm->cmd_type),
120 lsm->cmd_type);
121
122 ret = lttcomm_send_creds_unix_sock(sessiond_socket, lsm,
123 sizeof(struct lttcomm_session_msg));
124 if (ret < 0) {
125 ret = -LTTNG_ERR_FATAL;
126 }
127
128 end:
129 return ret;
130 }
131
132 /*
133 * Send var len data to the session daemon.
134 *
135 * On success, returns the number of bytes sent (>=0)
136 * On error, returns -1
137 */
138 static int send_session_varlen(const void *data, size_t len)
139 {
140 int ret;
141
142 if (!connected) {
143 ret = -LTTNG_ERR_NO_SESSIOND;
144 goto end;
145 }
146
147 if (!data || !len) {
148 ret = 0;
149 goto end;
150 }
151
152 ret = lttcomm_send_unix_sock(sessiond_socket, data, len);
153 if (ret < 0) {
154 ret = -LTTNG_ERR_FATAL;
155 }
156
157 end:
158 return ret;
159 }
160
161 /*
162 * Send file descriptors to the session daemon.
163 *
164 * On success, returns the number of bytes sent (>=0)
165 * On error, returns -1
166 */
167 static int send_session_fds(const int *fds, size_t nb_fd)
168 {
169 int ret;
170
171 if (!connected) {
172 ret = -LTTNG_ERR_NO_SESSIOND;
173 goto end;
174 }
175
176 if (!fds || !nb_fd) {
177 ret = 0;
178 goto end;
179 }
180
181 ret = lttcomm_send_fds_unix_sock(sessiond_socket, fds, nb_fd);
182 if (ret < 0) {
183 ret = -LTTNG_ERR_FATAL;
184 }
185
186 end:
187 return ret;
188 }
189
190 /*
191 * Receive data from the sessiond socket.
192 *
193 * On success, returns the number of bytes received (>=0)
194 * On error, returns a negative lttng_error_code.
195 */
196 static int recv_data_sessiond(void *buf, size_t len)
197 {
198 int ret;
199
200 assert(len > 0);
201
202 if (!connected) {
203 ret = -LTTNG_ERR_NO_SESSIOND;
204 goto end;
205 }
206
207 ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len);
208 if (ret < 0) {
209 ret = -LTTNG_ERR_FATAL;
210 } else if (ret == 0) {
211 ret = -LTTNG_ERR_NO_SESSIOND;
212 }
213
214 end:
215 return ret;
216 }
217
218 /*
219 * Receive a payload from the session daemon by appending to an existing
220 * payload.
221 * On success, returns the number of bytes received (>=0)
222 * On error, returns a negative lttng_error_code.
223 */
224 static int recv_payload_sessiond(struct lttng_payload *payload, size_t len)
225 {
226 int ret;
227 const size_t original_payload_size = payload->buffer.size;
228
229 ret = lttng_dynamic_buffer_set_size(
230 &payload->buffer, payload->buffer.size + len);
231 if (ret) {
232 ret = -LTTNG_ERR_NOMEM;
233 goto end;
234 }
235
236 ret = recv_data_sessiond(
237 payload->buffer.data + original_payload_size, len);
238 end:
239 return ret;
240 }
241
242 /*
243 * Check if we are in the specified group.
244 *
245 * If yes return 1, else return -1.
246 */
247 LTTNG_HIDDEN
248 int lttng_check_tracing_group(void)
249 {
250 gid_t *grp_list, tracing_gid;
251 int grp_list_size, grp_id, i;
252 int ret = -1;
253 const char *grp_name = tracing_group;
254
255 /* Get GID of group 'tracing' */
256 if (utils_get_group_id(grp_name, false, &tracing_gid)) {
257 /* If grp_tracing is NULL, the group does not exist. */
258 goto end;
259 }
260
261 /* Get number of supplementary group IDs */
262 grp_list_size = getgroups(0, NULL);
263 if (grp_list_size < 0) {
264 PERROR("getgroups");
265 goto end;
266 }
267
268 /* Alloc group list of the right size */
269 grp_list = zmalloc(grp_list_size * sizeof(gid_t));
270 if (!grp_list) {
271 PERROR("malloc");
272 goto end;
273 }
274 grp_id = getgroups(grp_list_size, grp_list);
275 if (grp_id < 0) {
276 PERROR("getgroups");
277 goto free_list;
278 }
279
280 for (i = 0; i < grp_list_size; i++) {
281 if (grp_list[i] == tracing_gid) {
282 ret = 1;
283 break;
284 }
285 }
286
287 free_list:
288 free(grp_list);
289
290 end:
291 return ret;
292 }
293
294 static int check_enough_available_memory(size_t num_bytes_requested_per_cpu)
295 {
296 int ret;
297 long num_cpu;
298 size_t best_mem_info;
299 size_t num_bytes_requested_total;
300
301 /*
302 * Get the number of CPU currently online to compute the amount of
303 * memory needed to create a buffer for every CPU.
304 */
305 num_cpu = sysconf(_SC_NPROCESSORS_ONLN);
306 if (num_cpu == -1) {
307 goto error;
308 }
309
310 num_bytes_requested_total = num_bytes_requested_per_cpu * num_cpu;
311
312 /*
313 * Try to get the `MemAvail` field of `/proc/meminfo`. This is the most
314 * reliable estimate we can get but it is only exposed by the kernel
315 * since 3.14. (See Linux kernel commit:
316 * 34e431b0ae398fc54ea69ff85ec700722c9da773)
317 */
318 ret = utils_get_memory_available(&best_mem_info);
319 if (ret >= 0) {
320 goto success;
321 }
322
323 /*
324 * As a backup plan, use `MemTotal` field of `/proc/meminfo`. This
325 * is a sanity check for obvious user error.
326 */
327 ret = utils_get_memory_total(&best_mem_info);
328 if (ret >= 0) {
329 goto success;
330 }
331
332 error:
333 return -1;
334 success:
335 return best_mem_info >= num_bytes_requested_total;
336 }
337
338 /*
339 * Try connect to session daemon with sock_path.
340 *
341 * Return 0 on success, else -1
342 */
343 static int try_connect_sessiond(const char *sock_path)
344 {
345 int ret;
346
347 /* If socket exist, we check if the daemon listens for connect. */
348 ret = access(sock_path, F_OK);
349 if (ret < 0) {
350 /* Not alive */
351 goto error;
352 }
353
354 ret = lttcomm_connect_unix_sock(sock_path);
355 if (ret < 0) {
356 /* Not alive. */
357 goto error;
358 }
359
360 ret = lttcomm_close_unix_sock(ret);
361 if (ret < 0) {
362 PERROR("lttcomm_close_unix_sock");
363 }
364
365 return 0;
366
367 error:
368 return -1;
369 }
370
371 /*
372 * Set sessiond socket path by putting it in the global sessiond_sock_path
373 * variable.
374 *
375 * Returns 0 on success, negative value on failure (the sessiond socket path
376 * is somehow too long or ENOMEM).
377 */
378 static int set_session_daemon_path(void)
379 {
380 int in_tgroup = 0; /* In tracing group. */
381 uid_t uid;
382
383 uid = getuid();
384
385 if (uid != 0) {
386 /* Are we in the tracing group ? */
387 in_tgroup = lttng_check_tracing_group();
388 }
389
390 if ((uid == 0) || in_tgroup) {
391 const int ret = lttng_strncpy(sessiond_sock_path,
392 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK,
393 sizeof(sessiond_sock_path));
394
395 if (ret) {
396 goto error;
397 }
398 }
399
400 if (uid != 0) {
401 int ret;
402
403 if (in_tgroup) {
404 /* Tracing group. */
405 ret = try_connect_sessiond(sessiond_sock_path);
406 if (ret >= 0) {
407 goto end;
408 }
409 /* Global session daemon not available... */
410 }
411 /* ...or not in tracing group (and not root), default */
412
413 /*
414 * With GNU C < 2.1, snprintf returns -1 if the target buffer
415 * is too small;
416 * With GNU C >= 2.1, snprintf returns the required size
417 * (excluding closing null)
418 */
419 ret = snprintf(sessiond_sock_path, sizeof(sessiond_sock_path),
420 DEFAULT_HOME_CLIENT_UNIX_SOCK, utils_get_home_dir());
421 if ((ret < 0) || (ret >= sizeof(sessiond_sock_path))) {
422 goto error;
423 }
424 }
425 end:
426 return 0;
427
428 error:
429 return -1;
430 }
431
432 /*
433 * Connect to the LTTng session daemon.
434 *
435 * On success, return the socket's file descriptor. On error, return -1.
436 */
437 LTTNG_HIDDEN int connect_sessiond(void)
438 {
439 int ret;
440
441 ret = set_session_daemon_path();
442 if (ret < 0) {
443 goto error;
444 }
445
446 /* Connect to the sesssion daemon. */
447 ret = lttcomm_connect_unix_sock(sessiond_sock_path);
448 if (ret < 0) {
449 goto error;
450 }
451
452 return ret;
453
454 error:
455 return -1;
456 }
457
458 static void reset_global_sessiond_connection_state(void)
459 {
460 sessiond_socket = -1;
461 connected = 0;
462 }
463
464 /*
465 * Clean disconnect from the session daemon.
466 *
467 * On success, return 0. On error, return -1.
468 */
469 static int disconnect_sessiond(void)
470 {
471 int ret = 0;
472
473 if (connected) {
474 ret = lttcomm_close_unix_sock(sessiond_socket);
475 reset_global_sessiond_connection_state();
476 }
477
478 return ret;
479 }
480
481 static int recv_sessiond_optional_data(size_t len, void **user_buf,
482 size_t *user_len)
483 {
484 int ret = 0;
485 void *buf = NULL;
486
487 if (len) {
488 if (!user_len) {
489 ret = -LTTNG_ERR_INVALID;
490 goto end;
491 }
492
493 buf = zmalloc(len);
494 if (!buf) {
495 ret = -ENOMEM;
496 goto end;
497 }
498
499 ret = recv_data_sessiond(buf, len);
500 if (ret < 0) {
501 goto end;
502 }
503
504 if (!user_buf) {
505 ret = -LTTNG_ERR_INVALID;
506 goto end;
507 }
508
509 /* Move ownership of command header buffer to user. */
510 *user_buf = buf;
511 buf = NULL;
512 *user_len = len;
513 } else {
514 /* No command header. */
515 if (user_len) {
516 *user_len = 0;
517 }
518
519 if (user_buf) {
520 *user_buf = NULL;
521 }
522 }
523
524 end:
525 free(buf);
526 return ret;
527 }
528
529 /*
530 * Ask the session daemon a specific command and put the data into buf.
531 * Takes extra var. len. data and file descriptors as input to send to the
532 * session daemon.
533 *
534 * Return size of data (only payload, not header) or a negative error code.
535 */
536 LTTNG_HIDDEN
537 int lttng_ctl_ask_sessiond_fds_varlen(struct lttcomm_session_msg *lsm,
538 const int *fds, size_t nb_fd, const void *vardata,
539 size_t vardata_len, void **user_payload_buf,
540 void **user_cmd_header_buf, size_t *user_cmd_header_len)
541 {
542 int ret;
543 size_t payload_len;
544 struct lttcomm_lttng_msg llm;
545
546 ret = connect_sessiond();
547 if (ret < 0) {
548 ret = -LTTNG_ERR_NO_SESSIOND;
549 goto end;
550 } else {
551 sessiond_socket = ret;
552 connected = 1;
553 }
554
555 ret = send_session_msg(lsm);
556 if (ret < 0) {
557 /* Ret value is a valid lttng error code. */
558 goto end;
559 }
560 /* Send var len data */
561 ret = send_session_varlen(vardata, vardata_len);
562 if (ret < 0) {
563 /* Ret value is a valid lttng error code. */
564 goto end;
565 }
566
567 /* Send fds */
568 ret = send_session_fds(fds, nb_fd);
569 if (ret < 0) {
570 /* Ret value is a valid lttng error code. */
571 goto end;
572 }
573
574 /* Get header from data transmission */
575 ret = recv_data_sessiond(&llm, sizeof(llm));
576 if (ret < 0) {
577 /* Ret value is a valid lttng error code. */
578 goto end;
579 }
580
581 /* Check error code if OK */
582 if (llm.ret_code != LTTNG_OK) {
583 ret = -llm.ret_code;
584 goto end;
585 }
586
587 /* Get command header from data transmission */
588 ret = recv_sessiond_optional_data(llm.cmd_header_size,
589 user_cmd_header_buf, user_cmd_header_len);
590 if (ret < 0) {
591 goto end;
592 }
593
594 /* Get payload from data transmission */
595 ret = recv_sessiond_optional_data(llm.data_size, user_payload_buf,
596 &payload_len);
597 if (ret < 0) {
598 goto end;
599 }
600
601 ret = llm.data_size;
602
603 end:
604 disconnect_sessiond();
605 return ret;
606 }
607
608 LTTNG_HIDDEN
609 int lttng_ctl_ask_sessiond_payload(struct lttng_payload_view *message,
610 struct lttng_payload *reply)
611 {
612 int ret;
613 struct lttcomm_lttng_msg llm;
614 const int fd_count = lttng_payload_view_get_fd_handle_count(message);
615
616 assert(reply->buffer.size == 0);
617 assert(lttng_dynamic_pointer_array_get_count(&reply->_fd_handles) == 0);
618
619 ret = connect_sessiond();
620 if (ret < 0) {
621 ret = -LTTNG_ERR_NO_SESSIOND;
622 goto end;
623 } else {
624 sessiond_socket = ret;
625 connected = 1;
626 }
627
628 /* Send command to session daemon */
629 ret = lttcomm_send_creds_unix_sock(sessiond_socket, message->buffer.data,
630 message->buffer.size);
631 if (ret < 0) {
632 ret = -LTTNG_ERR_FATAL;
633 goto end;
634 }
635
636 if (fd_count > 0) {
637 ret = lttcomm_send_payload_view_fds_unix_sock(sessiond_socket,
638 message);
639 if (ret < 0) {
640 ret = -LTTNG_ERR_FATAL;
641 goto end;
642 }
643 }
644
645 /* Get header from data transmission */
646 ret = recv_payload_sessiond(reply, sizeof(llm));
647 if (ret < 0) {
648 /* Ret value is a valid lttng error code. */
649 goto end;
650 }
651
652 llm = *((typeof(llm) *) reply->buffer.data);
653
654 /* Check error code if OK */
655 if (llm.ret_code != LTTNG_OK) {
656 if (llm.ret_code < LTTNG_OK || llm.ret_code >= LTTNG_ERR_NR) {
657 /* Invalid error code received. */
658 ret = -LTTNG_ERR_UNK;
659 } else {
660 ret = -llm.ret_code;
661 }
662 goto end;
663 }
664
665 if (llm.cmd_header_size > 0) {
666 ret = recv_payload_sessiond(reply, llm.cmd_header_size);
667 if (ret < 0) {
668 goto end;
669 }
670 }
671
672 /* Get command header from data transmission */
673 if (llm.data_size > 0) {
674 ret = recv_payload_sessiond(reply, llm.data_size);
675 if (ret < 0) {
676 goto end;
677 }
678 }
679
680 if (llm.fd_count > 0) {
681 ret = lttcomm_recv_payload_fds_unix_sock(
682 sessiond_socket, llm.fd_count, reply);
683 if (ret < 0) {
684 goto end;
685 }
686 }
687
688 /* Don't return the llm header to the caller. */
689 memmove(reply->buffer.data, reply->buffer.data + sizeof(llm),
690 reply->buffer.size - sizeof(llm));
691 ret = lttng_dynamic_buffer_set_size(
692 &reply->buffer, reply->buffer.size - sizeof(llm));
693 if (ret) {
694 /* Can't happen as size is reduced. */
695 abort();
696 }
697
698 ret = reply->buffer.size;
699
700 end:
701 disconnect_sessiond();
702 return ret;
703 }
704
705 /*
706 * Create lttng handle and return pointer.
707 *
708 * The returned pointer will be NULL in case of malloc() error.
709 */
710 struct lttng_handle *lttng_create_handle(const char *session_name,
711 struct lttng_domain *domain)
712 {
713 int ret;
714 struct lttng_handle *handle = NULL;
715
716 handle = zmalloc(sizeof(struct lttng_handle));
717 if (handle == NULL) {
718 PERROR("malloc handle");
719 goto end;
720 }
721
722 /* Copy session name */
723 ret = lttng_strncpy(handle->session_name, session_name ? : "",
724 sizeof(handle->session_name));
725 if (ret) {
726 goto error;
727 }
728
729 /* Copy lttng domain or leave initialized to 0. */
730 if (domain) {
731 lttng_ctl_copy_lttng_domain(&handle->domain, domain);
732 }
733
734 end:
735 return handle;
736 error:
737 free(handle);
738 return NULL;
739 }
740
741 /*
742 * Destroy handle by free(3) the pointer.
743 */
744 void lttng_destroy_handle(struct lttng_handle *handle)
745 {
746 free(handle);
747 }
748
749 /*
750 * Register an outside consumer.
751 *
752 * Returns size of returned session payload data or a negative error code.
753 */
754 int lttng_register_consumer(struct lttng_handle *handle,
755 const char *socket_path)
756 {
757 int ret;
758 struct lttcomm_session_msg lsm;
759
760 if (handle == NULL || socket_path == NULL) {
761 ret = -LTTNG_ERR_INVALID;
762 goto end;
763 }
764
765 memset(&lsm, 0, sizeof(lsm));
766 lsm.cmd_type = LTTNG_REGISTER_CONSUMER;
767 ret = lttng_strncpy(lsm.session.name, handle->session_name,
768 sizeof(lsm.session.name));
769 if (ret) {
770 ret = -LTTNG_ERR_INVALID;
771 goto end;
772 }
773
774 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
775
776 ret = lttng_strncpy(lsm.u.reg.path, socket_path,
777 sizeof(lsm.u.reg.path));
778 if (ret) {
779 ret = -LTTNG_ERR_INVALID;
780 goto end;
781 }
782
783 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
784 end:
785 return ret;
786 }
787
788 /*
789 * Start tracing for all traces of the session.
790 *
791 * Returns size of returned session payload data or a negative error code.
792 */
793 int lttng_start_tracing(const char *session_name)
794 {
795 int ret;
796 struct lttcomm_session_msg lsm;
797
798 if (session_name == NULL) {
799 ret = -LTTNG_ERR_INVALID;
800 goto end;
801 }
802
803 memset(&lsm, 0, sizeof(lsm));
804 lsm.cmd_type = LTTNG_START_TRACE;
805
806 ret = lttng_strncpy(lsm.session.name, session_name,
807 sizeof(lsm.session.name));
808 if (ret) {
809 ret = -LTTNG_ERR_INVALID;
810 goto end;
811 }
812
813 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
814 end:
815 return ret;
816 }
817
818 /*
819 * Stop tracing for all traces of the session.
820 */
821 static int _lttng_stop_tracing(const char *session_name, int wait)
822 {
823 int ret, data_ret;
824 struct lttcomm_session_msg lsm;
825
826 if (session_name == NULL) {
827 ret = -LTTNG_ERR_INVALID;
828 goto error;
829 }
830
831 memset(&lsm, 0, sizeof(lsm));
832 lsm.cmd_type = LTTNG_STOP_TRACE;
833
834 ret = lttng_strncpy(lsm.session.name, session_name,
835 sizeof(lsm.session.name));
836 if (ret) {
837 ret = -LTTNG_ERR_INVALID;
838 goto error;
839 }
840
841 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
842 if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
843 goto error;
844 }
845
846 if (!wait) {
847 goto end;
848 }
849
850 /* Check for data availability */
851 do {
852 data_ret = lttng_data_pending(session_name);
853 if (data_ret < 0) {
854 /* Return the data available call error. */
855 ret = data_ret;
856 goto error;
857 }
858
859 /*
860 * Data sleep time before retrying (in usec). Don't sleep if the
861 * call returned value indicates availability.
862 */
863 if (data_ret) {
864 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
865 }
866 } while (data_ret != 0);
867
868 end:
869 error:
870 return ret;
871 }
872
873 /*
874 * Stop tracing and wait for data availability.
875 */
876 int lttng_stop_tracing(const char *session_name)
877 {
878 return _lttng_stop_tracing(session_name, 1);
879 }
880
881 /*
882 * Stop tracing but _don't_ wait for data availability.
883 */
884 int lttng_stop_tracing_no_wait(const char *session_name)
885 {
886 return _lttng_stop_tracing(session_name, 0);
887 }
888
889 /*
890 * Add context to a channel.
891 *
892 * If the given channel is NULL, add the contexts to all channels.
893 * The event_name param is ignored.
894 *
895 * Returns the size of the returned payload data or a negative error code.
896 */
897 int lttng_add_context(struct lttng_handle *handle,
898 struct lttng_event_context *ctx, const char *event_name,
899 const char *channel_name)
900 {
901 int ret;
902 size_t len = 0;
903 char *buf = NULL;
904 struct lttcomm_session_msg lsm;
905
906 /* Safety check. Both are mandatory. */
907 if (handle == NULL || ctx == NULL) {
908 ret = -LTTNG_ERR_INVALID;
909 goto end;
910 }
911
912 memset(&lsm, 0, sizeof(lsm));
913 lsm.cmd_type = LTTNG_ADD_CONTEXT;
914
915 /* If no channel name, send empty string. */
916 ret = lttng_strncpy(lsm.u.context.channel_name, channel_name ?: "",
917 sizeof(lsm.u.context.channel_name));
918 if (ret) {
919 ret = -LTTNG_ERR_INVALID;
920 goto end;
921 }
922
923 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
924 ret = lttng_strncpy(lsm.session.name, handle->session_name,
925 sizeof(lsm.session.name));
926 if (ret) {
927 ret = -LTTNG_ERR_INVALID;
928 goto end;
929 }
930
931 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
932 size_t provider_len, ctx_len;
933 const char *provider_name = ctx->u.app_ctx.provider_name;
934 const char *ctx_name = ctx->u.app_ctx.ctx_name;
935
936 if (!provider_name || !ctx_name) {
937 ret = -LTTNG_ERR_INVALID;
938 goto end;
939 }
940
941 provider_len = strlen(provider_name);
942 if (provider_len == 0) {
943 ret = -LTTNG_ERR_INVALID;
944 goto end;
945 }
946 lsm.u.context.provider_name_len = provider_len;
947
948 ctx_len = strlen(ctx_name);
949 if (ctx_len == 0) {
950 ret = -LTTNG_ERR_INVALID;
951 goto end;
952 }
953 lsm.u.context.context_name_len = ctx_len;
954
955 len = provider_len + ctx_len;
956 buf = zmalloc(len);
957 if (!buf) {
958 ret = -LTTNG_ERR_NOMEM;
959 goto end;
960 }
961
962 memcpy(buf, provider_name, provider_len);
963 memcpy(buf + provider_len, ctx_name, ctx_len);
964 }
965 memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context));
966
967 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
968 /*
969 * Don't leak application addresses to the sessiond.
970 * This is only necessary when ctx is for an app ctx otherwise
971 * the values inside the union (type & config) are overwritten.
972 */
973 lsm.u.context.ctx.u.app_ctx.provider_name = NULL;
974 lsm.u.context.ctx.u.app_ctx.ctx_name = NULL;
975 }
976
977 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, buf, len, NULL);
978 end:
979 free(buf);
980 return ret;
981 }
982
983 /*
984 * Enable event(s) for a channel.
985 *
986 * If no event name is specified, all events are enabled.
987 * If no channel name is specified, the default 'channel0' is used.
988 *
989 * Returns size of returned session payload data or a negative error code.
990 */
991 int lttng_enable_event(struct lttng_handle *handle,
992 struct lttng_event *ev, const char *channel_name)
993 {
994 return lttng_enable_event_with_exclusions(handle, ev, channel_name,
995 NULL, 0, NULL);
996 }
997
998 /*
999 * Create or enable an event with a filter expression.
1000 *
1001 * Return negative error value on error.
1002 * Return size of returned session payload data if OK.
1003 */
1004 int lttng_enable_event_with_filter(struct lttng_handle *handle,
1005 struct lttng_event *event, const char *channel_name,
1006 const char *filter_expression)
1007 {
1008 return lttng_enable_event_with_exclusions(handle, event, channel_name,
1009 filter_expression, 0, NULL);
1010 }
1011
1012 /*
1013 * Depending on the event, return a newly allocated agent filter expression or
1014 * NULL if not applicable.
1015 *
1016 * An event with NO loglevel and the name is * will return NULL.
1017 */
1018 static char *set_agent_filter(const char *filter, struct lttng_event *ev)
1019 {
1020 int err;
1021 char *agent_filter = NULL;
1022
1023 assert(ev);
1024
1025 /* Don't add filter for the '*' event. */
1026 if (strcmp(ev->name, "*") != 0) {
1027 if (filter) {
1028 err = asprintf(&agent_filter, "(%s) && (logger_name == \"%s\")", filter,
1029 ev->name);
1030 } else {
1031 err = asprintf(&agent_filter, "logger_name == \"%s\"", ev->name);
1032 }
1033 if (err < 0) {
1034 PERROR("asprintf");
1035 goto error;
1036 }
1037 }
1038
1039 /* Add loglevel filtering if any for the JUL domain. */
1040 if (ev->loglevel_type != LTTNG_EVENT_LOGLEVEL_ALL) {
1041 const char *op;
1042
1043 if (ev->loglevel_type == LTTNG_EVENT_LOGLEVEL_RANGE) {
1044 op = ">=";
1045 } else {
1046 op = "==";
1047 }
1048
1049 if (filter || agent_filter) {
1050 char *new_filter;
1051
1052 err = asprintf(&new_filter, "(%s) && (int_loglevel %s %d)",
1053 agent_filter ? agent_filter : filter, op,
1054 ev->loglevel);
1055 if (agent_filter) {
1056 free(agent_filter);
1057 }
1058 agent_filter = new_filter;
1059 } else {
1060 err = asprintf(&agent_filter, "int_loglevel %s %d", op,
1061 ev->loglevel);
1062 }
1063 if (err < 0) {
1064 PERROR("asprintf");
1065 goto error;
1066 }
1067 }
1068
1069 return agent_filter;
1070 error:
1071 free(agent_filter);
1072 return NULL;
1073 }
1074
1075 /*
1076 * Enable event(s) for a channel, possibly with exclusions and a filter.
1077 * If no event name is specified, all events are enabled.
1078 * If no channel name is specified, the default name is used.
1079 * If filter expression is not NULL, the filter is set for the event.
1080 * If exclusion count is not zero, the exclusions are set for the event.
1081 * Returns size of returned session payload data or a negative error code.
1082 */
1083 int lttng_enable_event_with_exclusions(struct lttng_handle *handle,
1084 struct lttng_event *ev, const char *channel_name,
1085 const char *original_filter_expression,
1086 int exclusion_count, char **exclusion_list)
1087 {
1088 struct lttcomm_session_msg lsm;
1089 struct lttng_payload payload;
1090 int ret = 0, i;
1091 unsigned int free_filter_expression = 0;
1092 struct filter_parser_ctx *ctx = NULL;
1093
1094 /*
1095 * We have either a filter or some exclusions, so we need to set up
1096 * a variable-length payload from where to send the data.
1097 */
1098 lttng_payload_init(&payload);
1099
1100 /*
1101 * Cast as non-const since we may replace the filter expression
1102 * by a dynamically allocated string. Otherwise, the original
1103 * string is not modified.
1104 */
1105 char *filter_expression = (char *) original_filter_expression;
1106
1107 if (handle == NULL || ev == NULL) {
1108 ret = -LTTNG_ERR_INVALID;
1109 goto error;
1110 }
1111
1112 /*
1113 * Empty filter string will always be rejected by the parser
1114 * anyway, so treat this corner-case early to eliminate
1115 * lttng_fmemopen error for 0-byte allocation.
1116 */
1117 if (filter_expression && filter_expression[0] == '\0') {
1118 ret = -LTTNG_ERR_INVALID;
1119 goto error;
1120 }
1121
1122 memset(&lsm, 0, sizeof(lsm));
1123
1124 /* If no channel name, send empty string. */
1125 ret = lttng_strncpy(lsm.u.enable.channel_name, channel_name ?: "",
1126 sizeof(lsm.u.enable.channel_name));
1127 if (ret) {
1128 ret = -LTTNG_ERR_INVALID;
1129 goto error;
1130 }
1131
1132 lsm.cmd_type = LTTNG_ENABLE_EVENT;
1133 if (ev->name[0] == '\0') {
1134 /* Enable all events. */
1135 ret = lttng_strncpy(ev->name, "*", sizeof(ev->name));
1136 assert(ret == 0);
1137 }
1138
1139 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
1140 memcpy(&lsm.u.enable.event, ev, sizeof(lsm.u.enable.event));
1141
1142 ret = lttng_strncpy(lsm.session.name, handle->session_name,
1143 sizeof(lsm.session.name));
1144 if (ret) {
1145 ret = -LTTNG_ERR_INVALID;
1146 goto error;
1147 }
1148
1149 lsm.u.enable.exclusion_count = exclusion_count;
1150 lsm.u.enable.bytecode_len = 0;
1151
1152 /* Parse filter expression. */
1153 if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
1154 || handle->domain.type == LTTNG_DOMAIN_LOG4J
1155 || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1156 if (handle->domain.type == LTTNG_DOMAIN_JUL ||
1157 handle->domain.type == LTTNG_DOMAIN_LOG4J ||
1158 handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1159 char *agent_filter;
1160
1161 /* Setup JUL filter if needed. */
1162 agent_filter = set_agent_filter(filter_expression, ev);
1163 if (!agent_filter) {
1164 if (!filter_expression) {
1165 /*
1166 * No JUL and no filter, just skip
1167 * everything below.
1168 */
1169 goto ask_sessiond;
1170 }
1171 } else {
1172 /*
1173 * With an agent filter, the original filter has
1174 * been added to it thus replace the filter
1175 * expression.
1176 */
1177 filter_expression = agent_filter;
1178 free_filter_expression = 1;
1179 }
1180 }
1181
1182 ret = filter_parser_ctx_create_from_filter_expression(filter_expression, &ctx);
1183 if (ret) {
1184 goto filter_error;
1185 }
1186
1187 lsm.u.enable.bytecode_len = sizeof(ctx->bytecode->b)
1188 + bytecode_get_len(&ctx->bytecode->b);
1189 lsm.u.enable.expression_len = strlen(filter_expression) + 1;
1190 }
1191
1192 ret = lttng_dynamic_buffer_set_capacity(&payload.buffer,
1193 lsm.u.enable.bytecode_len +
1194 lsm.u.enable.expression_len +
1195 LTTNG_SYMBOL_NAME_LEN *
1196 exclusion_count);
1197 if (ret) {
1198 ret = -LTTNG_ERR_EXCLUSION_NOMEM;
1199 goto mem_error;
1200 }
1201
1202 /* Put exclusion names first in the data. */
1203 for (i = 0; i < exclusion_count; i++) {
1204 size_t exclusion_len;
1205
1206 exclusion_len = lttng_strnlen(*(exclusion_list + i),
1207 LTTNG_SYMBOL_NAME_LEN);
1208 if (exclusion_len == LTTNG_SYMBOL_NAME_LEN) {
1209 /* Exclusion is not NULL-terminated. */
1210 ret = -LTTNG_ERR_INVALID;
1211 goto mem_error;
1212 }
1213
1214 ret = lttng_dynamic_buffer_append(&payload.buffer,
1215 *(exclusion_list + i), LTTNG_SYMBOL_NAME_LEN);
1216 if (ret) {
1217 goto mem_error;
1218 }
1219 }
1220
1221 /* Add filter expression next. */
1222 if (filter_expression) {
1223 ret = lttng_dynamic_buffer_append(&payload.buffer,
1224 filter_expression, lsm.u.enable.expression_len);
1225 if (ret) {
1226 goto mem_error;
1227 }
1228 }
1229 /* Add filter bytecode next. */
1230 if (ctx && lsm.u.enable.bytecode_len != 0) {
1231 ret = lttng_dynamic_buffer_append(&payload.buffer,
1232 &ctx->bytecode->b, lsm.u.enable.bytecode_len);
1233 if (ret) {
1234 goto mem_error;
1235 }
1236 }
1237 if (ev->extended.ptr) {
1238 struct lttng_event_extended *ev_ext =
1239 (struct lttng_event_extended *) ev->extended.ptr;
1240
1241 if (ev_ext->probe_location) {
1242 /*
1243 * lttng_userspace_probe_location_serialize returns the
1244 * number of bytes that was appended to the buffer.
1245 */
1246 ret = lttng_userspace_probe_location_serialize(
1247 ev_ext->probe_location, &payload);
1248 if (ret < 0) {
1249 goto mem_error;
1250 }
1251
1252 /*
1253 * Set the size of the userspace probe location element
1254 * of the buffer so that the receiving side knows where
1255 * to split it.
1256 */
1257 lsm.u.enable.userspace_probe_location_len = ret;
1258 }
1259 }
1260
1261 {
1262 struct lttng_payload_view view = lttng_payload_view_from_payload(
1263 &payload, 0, -1);
1264 int fd_count = lttng_payload_view_get_fd_handle_count(&view);
1265 int fd_to_send;
1266
1267 if (fd_count < 0) {
1268 goto mem_error;
1269 }
1270
1271 assert(fd_count == 0 || fd_count == 1);
1272 if (fd_count == 1) {
1273 struct fd_handle *handle =
1274 lttng_payload_view_pop_fd_handle(&view);
1275
1276 if (!handle) {
1277 goto mem_error;
1278 }
1279
1280 fd_to_send = fd_handle_get_fd(handle);
1281 fd_handle_put(handle);
1282 }
1283
1284 ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm,
1285 fd_count ? &fd_to_send : NULL, fd_count,
1286 view.buffer.size ? view.buffer.data : NULL,
1287 view.buffer.size, NULL, NULL, 0);
1288 }
1289
1290 mem_error:
1291 if (filter_expression && ctx) {
1292 filter_bytecode_free(ctx);
1293 filter_ir_free(ctx);
1294 filter_parser_ctx_free(ctx);
1295 }
1296 filter_error:
1297 if (free_filter_expression) {
1298 /*
1299 * The filter expression has been replaced and must be freed as
1300 * it is not the original filter expression received as a
1301 * parameter.
1302 */
1303 free(filter_expression);
1304 }
1305 error:
1306 /*
1307 * Return directly to the caller and don't ask the sessiond since
1308 * something went wrong in the parsing of data above.
1309 */
1310 lttng_payload_reset(&payload);
1311 return ret;
1312
1313 ask_sessiond:
1314 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1315 return ret;
1316 }
1317
1318 int lttng_disable_event_ext(struct lttng_handle *handle,
1319 struct lttng_event *ev, const char *channel_name,
1320 const char *original_filter_expression)
1321 {
1322 struct lttcomm_session_msg lsm;
1323 char *varlen_data;
1324 int ret = 0;
1325 unsigned int free_filter_expression = 0;
1326 struct filter_parser_ctx *ctx = NULL;
1327 /*
1328 * Cast as non-const since we may replace the filter expression
1329 * by a dynamically allocated string. Otherwise, the original
1330 * string is not modified.
1331 */
1332 char *filter_expression = (char *) original_filter_expression;
1333
1334 if (handle == NULL || ev == NULL) {
1335 ret = -LTTNG_ERR_INVALID;
1336 goto error;
1337 }
1338
1339 /*
1340 * Empty filter string will always be rejected by the parser
1341 * anyway, so treat this corner-case early to eliminate
1342 * lttng_fmemopen error for 0-byte allocation.
1343 */
1344 if (filter_expression && filter_expression[0] == '\0') {
1345 ret = -LTTNG_ERR_INVALID;
1346 goto error;
1347 }
1348
1349 memset(&lsm, 0, sizeof(lsm));
1350
1351 /* If no channel name, send empty string. */
1352 ret = lttng_strncpy(lsm.u.disable.channel_name, channel_name ?: "",
1353 sizeof(lsm.u.disable.channel_name));
1354 if (ret) {
1355 ret = -LTTNG_ERR_INVALID;
1356 goto error;
1357 }
1358
1359 lsm.cmd_type = LTTNG_DISABLE_EVENT;
1360
1361 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
1362 memcpy(&lsm.u.disable.event, ev, sizeof(lsm.u.disable.event));
1363
1364 ret = lttng_strncpy(lsm.session.name, handle->session_name,
1365 sizeof(lsm.session.name));
1366 if (ret) {
1367 ret = -LTTNG_ERR_INVALID;
1368 goto error;
1369 }
1370
1371 lsm.u.disable.bytecode_len = 0;
1372
1373 /*
1374 * For the JUL domain, a filter is enforced except for the
1375 * disable all event. This is done to avoid having the event in
1376 * all sessions thus filtering by logger name.
1377 */
1378 if (filter_expression == NULL &&
1379 (handle->domain.type != LTTNG_DOMAIN_JUL &&
1380 handle->domain.type != LTTNG_DOMAIN_LOG4J &&
1381 handle->domain.type != LTTNG_DOMAIN_PYTHON)) {
1382 goto ask_sessiond;
1383 }
1384
1385 /*
1386 * We have a filter, so we need to set up a variable-length
1387 * memory block from where to send the data.
1388 */
1389
1390 /* Parse filter expression */
1391 if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
1392 || handle->domain.type == LTTNG_DOMAIN_LOG4J
1393 || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1394 if (handle->domain.type == LTTNG_DOMAIN_JUL ||
1395 handle->domain.type == LTTNG_DOMAIN_LOG4J ||
1396 handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1397 char *agent_filter;
1398
1399 /* Setup JUL filter if needed. */
1400 agent_filter = set_agent_filter(filter_expression, ev);
1401 if (!agent_filter) {
1402 if (!filter_expression) {
1403 /*
1404 * No JUL and no filter, just skip
1405 * everything below.
1406 */
1407 goto ask_sessiond;
1408 }
1409 } else {
1410 /*
1411 * With a JUL filter, the original filter has
1412 * been added to it thus replace the filter
1413 * expression.
1414 */
1415 filter_expression = agent_filter;
1416 free_filter_expression = 1;
1417 }
1418 }
1419
1420 ret = filter_parser_ctx_create_from_filter_expression(filter_expression, &ctx);
1421 if (ret) {
1422 goto filter_error;
1423 }
1424
1425 lsm.u.enable.bytecode_len = sizeof(ctx->bytecode->b)
1426 + bytecode_get_len(&ctx->bytecode->b);
1427 lsm.u.enable.expression_len = strlen(filter_expression) + 1;
1428 }
1429
1430 varlen_data = zmalloc(lsm.u.disable.bytecode_len
1431 + lsm.u.disable.expression_len);
1432 if (!varlen_data) {
1433 ret = -LTTNG_ERR_EXCLUSION_NOMEM;
1434 goto mem_error;
1435 }
1436
1437 /* Add filter expression. */
1438 if (lsm.u.disable.expression_len != 0) {
1439 memcpy(varlen_data,
1440 filter_expression,
1441 lsm.u.disable.expression_len);
1442 }
1443 /* Add filter bytecode next. */
1444 if (ctx && lsm.u.disable.bytecode_len != 0) {
1445 memcpy(varlen_data
1446 + lsm.u.disable.expression_len,
1447 &ctx->bytecode->b,
1448 lsm.u.disable.bytecode_len);
1449 }
1450
1451 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, varlen_data,
1452 lsm.u.disable.bytecode_len + lsm.u.disable.expression_len, NULL);
1453 free(varlen_data);
1454
1455 mem_error:
1456 if (filter_expression && ctx) {
1457 filter_bytecode_free(ctx);
1458 filter_ir_free(ctx);
1459 filter_parser_ctx_free(ctx);
1460 }
1461 filter_error:
1462 if (free_filter_expression) {
1463 /*
1464 * The filter expression has been replaced and must be freed as
1465 * it is not the original filter expression received as a
1466 * parameter.
1467 */
1468 free(filter_expression);
1469 }
1470 error:
1471 /*
1472 * Return directly to the caller and don't ask the sessiond since
1473 * something went wrong in the parsing of data above.
1474 */
1475 return ret;
1476
1477 ask_sessiond:
1478 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1479 return ret;
1480 }
1481
1482 /*
1483 * Disable event(s) of a channel and domain.
1484 * If no event name is specified, all events are disabled.
1485 * If no channel name is specified, the default 'channel0' is used.
1486 * Returns size of returned session payload data or a negative error code.
1487 */
1488 int lttng_disable_event(struct lttng_handle *handle, const char *name,
1489 const char *channel_name)
1490 {
1491 int ret;
1492 struct lttng_event ev;
1493
1494 memset(&ev, 0, sizeof(ev));
1495 ev.loglevel = -1;
1496 ev.type = LTTNG_EVENT_ALL;
1497 ret = lttng_strncpy(ev.name, name ?: "", sizeof(ev.name));
1498 if (ret) {
1499 ret = -LTTNG_ERR_INVALID;
1500 goto end;
1501 }
1502
1503 ret = lttng_disable_event_ext(handle, &ev, channel_name, NULL);
1504 end:
1505 return ret;
1506 }
1507
1508 struct lttng_channel *lttng_channel_create(struct lttng_domain *domain)
1509 {
1510 struct lttng_channel *channel = NULL;
1511 struct lttng_channel_extended *extended = NULL;
1512
1513 if (!domain) {
1514 goto error;
1515 }
1516
1517 /* Validate domain. */
1518 switch (domain->type) {
1519 case LTTNG_DOMAIN_UST:
1520 switch (domain->buf_type) {
1521 case LTTNG_BUFFER_PER_UID:
1522 case LTTNG_BUFFER_PER_PID:
1523 break;
1524 default:
1525 goto error;
1526 }
1527 break;
1528 case LTTNG_DOMAIN_KERNEL:
1529 if (domain->buf_type != LTTNG_BUFFER_GLOBAL) {
1530 goto error;
1531 }
1532 break;
1533 default:
1534 goto error;
1535 }
1536
1537 channel = zmalloc(sizeof(*channel));
1538 if (!channel) {
1539 goto error;
1540 }
1541
1542 extended = zmalloc(sizeof(*extended));
1543 if (!extended) {
1544 goto error;
1545 }
1546
1547 channel->attr.extended.ptr = extended;
1548
1549 lttng_channel_set_default_attr(domain, &channel->attr);
1550 return channel;
1551 error:
1552 free(channel);
1553 free(extended);
1554 return NULL;
1555 }
1556
1557 void lttng_channel_destroy(struct lttng_channel *channel)
1558 {
1559 if (!channel) {
1560 return;
1561 }
1562
1563 if (channel->attr.extended.ptr) {
1564 free(channel->attr.extended.ptr);
1565 }
1566 free(channel);
1567 }
1568
1569 /*
1570 * Enable channel per domain
1571 * Returns size of returned session payload data or a negative error code.
1572 */
1573 int lttng_enable_channel(struct lttng_handle *handle,
1574 struct lttng_channel *in_chan)
1575 {
1576 int ret;
1577 struct lttcomm_session_msg lsm;
1578 size_t total_buffer_size_needed_per_cpu = 0;
1579
1580 /* NULL arguments are forbidden. No default values. */
1581 if (handle == NULL || in_chan == NULL) {
1582 return -LTTNG_ERR_INVALID;
1583 }
1584
1585 memset(&lsm, 0, sizeof(lsm));
1586 memcpy(&lsm.u.channel.chan, in_chan, sizeof(lsm.u.channel.chan));
1587 lsm.u.channel.chan.attr.extended.ptr = NULL;
1588
1589 if (!in_chan->attr.extended.ptr) {
1590 struct lttng_channel *channel;
1591 struct lttng_channel_extended *extended;
1592
1593 channel = lttng_channel_create(&handle->domain);
1594 if (!channel) {
1595 return -LTTNG_ERR_NOMEM;
1596 }
1597
1598 /*
1599 * Create a new channel in order to use default extended
1600 * attribute values.
1601 */
1602 extended = (struct lttng_channel_extended *)
1603 channel->attr.extended.ptr;
1604 memcpy(&lsm.u.channel.extended, extended, sizeof(*extended));
1605 lttng_channel_destroy(channel);
1606 } else {
1607 struct lttng_channel_extended *extended;
1608
1609 extended = (struct lttng_channel_extended *)
1610 in_chan->attr.extended.ptr;
1611 memcpy(&lsm.u.channel.extended, extended, sizeof(*extended));
1612 }
1613
1614 /*
1615 * Verify that the amount of memory required to create the requested
1616 * buffer is available on the system at the moment.
1617 */
1618 total_buffer_size_needed_per_cpu = lsm.u.channel.chan.attr.num_subbuf *
1619 lsm.u.channel.chan.attr.subbuf_size;
1620 if (!check_enough_available_memory(total_buffer_size_needed_per_cpu)) {
1621 return -LTTNG_ERR_NOMEM;
1622 }
1623
1624 lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
1625 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
1626
1627 ret = lttng_strncpy(lsm.session.name, handle->session_name,
1628 sizeof(lsm.session.name));
1629 if (ret) {
1630 ret = -LTTNG_ERR_INVALID;
1631 goto end;
1632 }
1633
1634 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1635 end:
1636 return ret;
1637 }
1638
1639 /*
1640 * All tracing will be stopped for registered events of the channel.
1641 * Returns size of returned session payload data or a negative error code.
1642 */
1643 int lttng_disable_channel(struct lttng_handle *handle, const char *name)
1644 {
1645 int ret;
1646 struct lttcomm_session_msg lsm;
1647
1648 /* Safety check. Both are mandatory. */
1649 if (handle == NULL || name == NULL) {
1650 return -LTTNG_ERR_INVALID;
1651 }
1652
1653 memset(&lsm, 0, sizeof(lsm));
1654
1655 lsm.cmd_type = LTTNG_DISABLE_CHANNEL;
1656
1657 ret = lttng_strncpy(lsm.u.disable.channel_name, name,
1658 sizeof(lsm.u.disable.channel_name));
1659 if (ret) {
1660 ret = -LTTNG_ERR_INVALID;
1661 goto end;
1662 }
1663
1664 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
1665
1666 ret = lttng_strncpy(lsm.session.name, handle->session_name,
1667 sizeof(lsm.session.name));
1668 if (ret) {
1669 ret = -LTTNG_ERR_INVALID;
1670 goto end;
1671 }
1672
1673 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1674 end:
1675 return ret;
1676 }
1677
1678 /*
1679 * Lists all available tracepoints of domain.
1680 * Sets the contents of the events array.
1681 * Returns the number of lttng_event entries in events;
1682 * on error, returns a negative value.
1683 */
1684 int lttng_list_tracepoints(struct lttng_handle *handle,
1685 struct lttng_event **events)
1686 {
1687 int ret;
1688 struct lttcomm_session_msg lsm;
1689
1690 if (handle == NULL) {
1691 return -LTTNG_ERR_INVALID;
1692 }
1693
1694 memset(&lsm, 0, sizeof(lsm));
1695 lsm.cmd_type = LTTNG_LIST_TRACEPOINTS;
1696 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
1697
1698 ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
1699 if (ret < 0) {
1700 return ret;
1701 }
1702
1703 return ret / sizeof(struct lttng_event);
1704 }
1705
1706 /*
1707 * Lists all available tracepoint fields of domain.
1708 * Sets the contents of the event field array.
1709 * Returns the number of lttng_event_field entries in events;
1710 * on error, returns a negative value.
1711 */
1712 int lttng_list_tracepoint_fields(struct lttng_handle *handle,
1713 struct lttng_event_field **fields)
1714 {
1715 int ret;
1716 struct lttcomm_session_msg lsm;
1717
1718 if (handle == NULL) {
1719 return -LTTNG_ERR_INVALID;
1720 }
1721
1722 memset(&lsm, 0, sizeof(lsm));
1723 lsm.cmd_type = LTTNG_LIST_TRACEPOINT_FIELDS;
1724 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
1725
1726 ret = lttng_ctl_ask_sessiond(&lsm, (void **) fields);
1727 if (ret < 0) {
1728 return ret;
1729 }
1730
1731 return ret / sizeof(struct lttng_event_field);
1732 }
1733
1734 /*
1735 * Lists all available kernel system calls. Allocates and sets the contents of
1736 * the events array.
1737 *
1738 * Returns the number of lttng_event entries in events; on error, returns a
1739 * negative value.
1740 */
1741 int lttng_list_syscalls(struct lttng_event **events)
1742 {
1743 int ret;
1744 struct lttcomm_session_msg lsm;
1745
1746 if (!events) {
1747 return -LTTNG_ERR_INVALID;
1748 }
1749
1750 memset(&lsm, 0, sizeof(lsm));
1751 lsm.cmd_type = LTTNG_LIST_SYSCALLS;
1752 /* Force kernel domain for system calls. */
1753 lsm.domain.type = LTTNG_DOMAIN_KERNEL;
1754
1755 ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
1756 if (ret < 0) {
1757 return ret;
1758 }
1759
1760 return ret / sizeof(struct lttng_event);
1761 }
1762
1763 /*
1764 * Returns a human readable string describing
1765 * the error code (a negative value).
1766 */
1767 const char *lttng_strerror(int code)
1768 {
1769 return error_get_str(code);
1770 }
1771
1772 enum lttng_error_code lttng_create_session_ext(
1773 struct lttng_session_descriptor *session_descriptor)
1774 {
1775 enum lttng_error_code ret_code;
1776 struct lttcomm_session_msg lsm = {
1777 .cmd_type = LTTNG_CREATE_SESSION_EXT,
1778 };
1779 void *reply = NULL;
1780 struct lttng_buffer_view reply_view;
1781 int reply_ret;
1782 bool sessiond_must_generate_ouput;
1783 struct lttng_dynamic_buffer payload;
1784 int ret;
1785 size_t descriptor_size;
1786 struct lttng_session_descriptor *descriptor_reply = NULL;
1787
1788 lttng_dynamic_buffer_init(&payload);
1789 if (!session_descriptor) {
1790 ret_code = LTTNG_ERR_INVALID;
1791 goto end;
1792 }
1793
1794 sessiond_must_generate_ouput =
1795 !lttng_session_descriptor_is_output_destination_initialized(
1796 session_descriptor);
1797 if (sessiond_must_generate_ouput) {
1798 const char *home_dir = utils_get_home_dir();
1799 size_t home_dir_len = home_dir ? strlen(home_dir) + 1 : 0;
1800
1801 if (!home_dir || home_dir_len > LTTNG_PATH_MAX) {
1802 ret_code = LTTNG_ERR_FATAL;
1803 goto end;
1804 }
1805
1806 lsm.u.create_session.home_dir_size = (uint16_t) home_dir_len;
1807 ret = lttng_dynamic_buffer_append(&payload, home_dir,
1808 home_dir_len);
1809 if (ret) {
1810 ret_code = LTTNG_ERR_NOMEM;
1811 goto end;
1812 }
1813 }
1814
1815 descriptor_size = payload.size;
1816 ret = lttng_session_descriptor_serialize(session_descriptor,
1817 &payload);
1818 if (ret) {
1819 ret_code = LTTNG_ERR_INVALID;
1820 goto end;
1821 }
1822 descriptor_size = payload.size - descriptor_size;
1823 lsm.u.create_session.session_descriptor_size = descriptor_size;
1824
1825 /* Command returns a session descriptor on success. */
1826 reply_ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, payload.data,
1827 payload.size, &reply);
1828 if (reply_ret < 0) {
1829 ret_code = -reply_ret;
1830 goto end;
1831 } else if (reply_ret == 0) {
1832 /* Socket unexpectedly closed by the session daemon. */
1833 ret_code = LTTNG_ERR_FATAL;
1834 goto end;
1835 }
1836
1837 reply_view = lttng_buffer_view_init(reply, 0, reply_ret);
1838 ret = lttng_session_descriptor_create_from_buffer(&reply_view,
1839 &descriptor_reply);
1840 if (ret < 0) {
1841 ret_code = LTTNG_ERR_FATAL;
1842 goto end;
1843 }
1844 ret_code = LTTNG_OK;
1845 lttng_session_descriptor_assign(session_descriptor, descriptor_reply);
1846 end:
1847 free(reply);
1848 lttng_dynamic_buffer_reset(&payload);
1849 lttng_session_descriptor_destroy(descriptor_reply);
1850 return ret_code;
1851 }
1852
1853 /*
1854 * Create a new session using name and url for destination.
1855 *
1856 * Return 0 on success else a negative LTTng error code.
1857 */
1858 int lttng_create_session(const char *name, const char *url)
1859 {
1860 int ret;
1861 ssize_t size;
1862 struct lttng_uri *uris = NULL;
1863 struct lttng_session_descriptor *descriptor = NULL;
1864 enum lttng_error_code ret_code;
1865
1866 if (!name) {
1867 ret = -LTTNG_ERR_INVALID;
1868 goto end;
1869 }
1870
1871 size = uri_parse_str_urls(url, NULL, &uris);
1872 if (size < 0) {
1873 ret = -LTTNG_ERR_INVALID;
1874 goto end;
1875 }
1876 switch (size) {
1877 case 0:
1878 descriptor = lttng_session_descriptor_create(name);
1879 break;
1880 case 1:
1881 if (uris[0].dtype != LTTNG_DST_PATH) {
1882 ret = -LTTNG_ERR_INVALID;
1883 goto end;
1884 }
1885 descriptor = lttng_session_descriptor_local_create(name,
1886 uris[0].dst.path);
1887 break;
1888 case 2:
1889 descriptor = lttng_session_descriptor_network_create(name, url,
1890 NULL);
1891 break;
1892 default:
1893 ret = -LTTNG_ERR_INVALID;
1894 goto end;
1895 }
1896 if (!descriptor) {
1897 ret = -LTTNG_ERR_INVALID;
1898 goto end;
1899 }
1900 ret_code = lttng_create_session_ext(descriptor);
1901 ret = ret_code == LTTNG_OK ? 0 : -ret_code;
1902 end:
1903 lttng_session_descriptor_destroy(descriptor);
1904 free(uris);
1905 return ret;
1906 }
1907
1908 /*
1909 * Create a session exclusively used for snapshot.
1910 *
1911 * Return 0 on success else a negative LTTng error code.
1912 */
1913 int lttng_create_session_snapshot(const char *name, const char *snapshot_url)
1914 {
1915 int ret;
1916 enum lttng_error_code ret_code;
1917 ssize_t size;
1918 struct lttng_uri *uris = NULL;
1919 struct lttng_session_descriptor *descriptor = NULL;
1920
1921 if (!name) {
1922 ret = -LTTNG_ERR_INVALID;
1923 goto end;
1924 }
1925
1926 size = uri_parse_str_urls(snapshot_url, NULL, &uris);
1927 if (size < 0) {
1928 ret = -LTTNG_ERR_INVALID;
1929 goto end;
1930 }
1931 /*
1932 * If the user does not specify a custom subdir, use the session name.
1933 */
1934 if (size > 0 && uris[0].dtype != LTTNG_DST_PATH &&
1935 strlen(uris[0].subdir) == 0) {
1936 ret = snprintf(uris[0].subdir, sizeof(uris[0].subdir), "%s",
1937 name);
1938 if (ret < 0) {
1939 PERROR("Failed to set session name as network destination sub-directory");
1940 ret = -LTTNG_ERR_FATAL;
1941 goto end;
1942 } else if (ret >= sizeof(uris[0].subdir)) {
1943 /* Truncated output. */
1944 ret = -LTTNG_ERR_INVALID;
1945 goto end;
1946 }
1947 }
1948
1949 switch (size) {
1950 case 0:
1951 descriptor = lttng_session_descriptor_snapshot_create(name);
1952 break;
1953 case 1:
1954 if (uris[0].dtype != LTTNG_DST_PATH) {
1955 ret = -LTTNG_ERR_INVALID;
1956 goto end;
1957 }
1958 descriptor = lttng_session_descriptor_snapshot_local_create(
1959 name,
1960 uris[0].dst.path);
1961 break;
1962 case 2:
1963 descriptor = lttng_session_descriptor_snapshot_network_create(
1964 name,
1965 snapshot_url,
1966 NULL);
1967 break;
1968 default:
1969 ret = -LTTNG_ERR_INVALID;
1970 goto end;
1971 }
1972 if (!descriptor) {
1973 ret = -LTTNG_ERR_INVALID;
1974 goto end;
1975 }
1976 ret_code = lttng_create_session_ext(descriptor);
1977 ret = ret_code == LTTNG_OK ? 0 : -ret_code;
1978 end:
1979 lttng_session_descriptor_destroy(descriptor);
1980 free(uris);
1981 return ret;
1982 }
1983
1984 /*
1985 * Create a session exclusively used for live.
1986 *
1987 * Return 0 on success else a negative LTTng error code.
1988 */
1989 int lttng_create_session_live(const char *name, const char *url,
1990 unsigned int timer_interval)
1991 {
1992 int ret;
1993 enum lttng_error_code ret_code;
1994 struct lttng_session_descriptor *descriptor = NULL;
1995
1996 if (!name) {
1997 ret = -LTTNG_ERR_INVALID;
1998 goto end;
1999 }
2000
2001 if (url) {
2002 descriptor = lttng_session_descriptor_live_network_create(
2003 name, url, NULL, timer_interval);
2004 } else {
2005 descriptor = lttng_session_descriptor_live_create(
2006 name, timer_interval);
2007 }
2008 if (!descriptor) {
2009 ret = -LTTNG_ERR_INVALID;
2010 goto end;
2011 }
2012 ret_code = lttng_create_session_ext(descriptor);
2013 ret = ret_code == LTTNG_OK ? 0 : -ret_code;
2014 end:
2015 lttng_session_descriptor_destroy(descriptor);
2016 return ret;
2017 }
2018
2019 /*
2020 * Stop the session and wait for the data before destroying it
2021 *
2022 * Return 0 on success else a negative LTTng error code.
2023 */
2024 int lttng_destroy_session(const char *session_name)
2025 {
2026 int ret;
2027 enum lttng_error_code ret_code;
2028 enum lttng_destruction_handle_status status;
2029 struct lttng_destruction_handle *handle = NULL;
2030
2031 /*
2032 * Stop the tracing and wait for the data to be
2033 * consumed.
2034 */
2035 ret = _lttng_stop_tracing(session_name, 1);
2036 if (ret && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
2037 goto end;
2038 }
2039
2040 ret_code = lttng_destroy_session_ext(session_name, &handle);
2041 if (ret_code != LTTNG_OK) {
2042 ret = (int) -ret_code;
2043 goto end;
2044 }
2045 assert(handle);
2046
2047 /* Block until the completion of the destruction of the session. */
2048 status = lttng_destruction_handle_wait_for_completion(handle, -1);
2049 if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED) {
2050 ret = -LTTNG_ERR_UNK;
2051 goto end;
2052 }
2053
2054 status = lttng_destruction_handle_get_result(handle, &ret_code);
2055 if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
2056 ret = -LTTNG_ERR_UNK;
2057 goto end;
2058 }
2059 ret = ret_code == LTTNG_OK ? 0 : -ret_code;
2060 end:
2061 lttng_destruction_handle_destroy(handle);
2062 return ret;
2063 }
2064
2065 /*
2066 * Destroy the session without waiting for the data.
2067 */
2068 int lttng_destroy_session_no_wait(const char *session_name)
2069 {
2070 enum lttng_error_code ret_code;
2071
2072 ret_code = lttng_destroy_session_ext(session_name, NULL);
2073 return ret_code == LTTNG_OK ? ret_code : -ret_code;
2074 }
2075
2076 /*
2077 * Ask the session daemon for all available sessions.
2078 * Sets the contents of the sessions array.
2079 * Returns the number of lttng_session entries in sessions;
2080 * on error, returns a negative value.
2081 */
2082 int lttng_list_sessions(struct lttng_session **out_sessions)
2083 {
2084 int ret;
2085 struct lttcomm_session_msg lsm;
2086 const size_t session_size = sizeof(struct lttng_session) +
2087 sizeof(struct lttng_session_extended);
2088 size_t session_count, i;
2089 struct lttng_session_extended *sessions_extended_begin;
2090 struct lttng_session *sessions = NULL;
2091
2092 memset(&lsm, 0, sizeof(lsm));
2093 lsm.cmd_type = LTTNG_LIST_SESSIONS;
2094 ret = lttng_ctl_ask_sessiond(&lsm, (void**) &sessions);
2095 if (ret <= 0) {
2096 goto end;
2097 }
2098 if (!sessions) {
2099 ret = -LTTNG_ERR_FATAL;
2100 goto end;
2101 }
2102
2103 if (ret % session_size) {
2104 ret = -LTTNG_ERR_UNK;
2105 free(sessions);
2106 *out_sessions = NULL;
2107 goto end;
2108 }
2109 session_count = (size_t) ret / session_size;
2110 sessions_extended_begin = (struct lttng_session_extended *)
2111 (&sessions[session_count]);
2112
2113 /* Set extended session info pointers. */
2114 for (i = 0; i < session_count; i++) {
2115 struct lttng_session *session = &sessions[i];
2116 struct lttng_session_extended *extended =
2117 &(sessions_extended_begin[i]);
2118
2119 session->extended.ptr = extended;
2120 }
2121
2122 ret = (int) session_count;
2123 *out_sessions = sessions;
2124 end:
2125 return ret;
2126 }
2127
2128 enum lttng_error_code lttng_session_get_creation_time(
2129 const struct lttng_session *session, uint64_t *creation_time)
2130 {
2131 enum lttng_error_code ret = LTTNG_OK;
2132 struct lttng_session_extended *extended;
2133
2134 if (!session || !creation_time || !session->extended.ptr) {
2135 ret = LTTNG_ERR_INVALID;
2136 goto end;
2137 }
2138
2139 extended = session->extended.ptr;
2140 if (!extended->creation_time.is_set) {
2141 /* Not created on the session daemon yet. */
2142 ret = LTTNG_ERR_SESSION_NOT_EXIST;
2143 goto end;
2144 }
2145 *creation_time = extended->creation_time.value;
2146 end:
2147 return ret;
2148 }
2149
2150 int lttng_set_session_shm_path(const char *session_name,
2151 const char *shm_path)
2152 {
2153 int ret;
2154 struct lttcomm_session_msg lsm;
2155
2156 if (session_name == NULL) {
2157 return -LTTNG_ERR_INVALID;
2158 }
2159
2160 memset(&lsm, 0, sizeof(lsm));
2161 lsm.cmd_type = LTTNG_SET_SESSION_SHM_PATH;
2162
2163 ret = lttng_strncpy(lsm.session.name, session_name,
2164 sizeof(lsm.session.name));
2165 if (ret) {
2166 ret = -LTTNG_ERR_INVALID;
2167 goto end;
2168 }
2169
2170 ret = lttng_strncpy(lsm.u.set_shm_path.shm_path, shm_path ?: "",
2171 sizeof(lsm.u.set_shm_path.shm_path));
2172 if (ret) {
2173 ret = -LTTNG_ERR_INVALID;
2174 goto end;
2175 }
2176
2177 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
2178 end:
2179 return ret;
2180 }
2181
2182 /*
2183 * Ask the session daemon for all available domains of a session.
2184 * Sets the contents of the domains array.
2185 * Returns the number of lttng_domain entries in domains;
2186 * on error, returns a negative value.
2187 */
2188 int lttng_list_domains(const char *session_name,
2189 struct lttng_domain **domains)
2190 {
2191 int ret;
2192 struct lttcomm_session_msg lsm;
2193
2194 if (session_name == NULL) {
2195 ret = -LTTNG_ERR_INVALID;
2196 goto error;
2197 }
2198
2199 memset(&lsm, 0, sizeof(lsm));
2200 lsm.cmd_type = LTTNG_LIST_DOMAINS;
2201
2202 ret = lttng_strncpy(lsm.session.name, session_name,
2203 sizeof(lsm.session.name));
2204 if (ret) {
2205 ret = -LTTNG_ERR_INVALID;
2206 goto error;
2207 }
2208
2209 ret = lttng_ctl_ask_sessiond(&lsm, (void**) domains);
2210 if (ret < 0) {
2211 goto error;
2212 }
2213
2214 return ret / sizeof(struct lttng_domain);
2215 error:
2216 return ret;
2217 }
2218
2219 /*
2220 * Ask the session daemon for all available channels of a session.
2221 * Sets the contents of the channels array.
2222 * Returns the number of lttng_channel entries in channels;
2223 * on error, returns a negative value.
2224 */
2225 int lttng_list_channels(struct lttng_handle *handle,
2226 struct lttng_channel **channels)
2227 {
2228 int ret;
2229 size_t channel_count, i;
2230 const size_t channel_size = sizeof(struct lttng_channel) +
2231 sizeof(struct lttng_channel_extended);
2232 struct lttcomm_session_msg lsm;
2233 void *extended_at;
2234
2235 if (handle == NULL) {
2236 ret = -LTTNG_ERR_INVALID;
2237 goto end;
2238 }
2239
2240 memset(&lsm, 0, sizeof(lsm));
2241 lsm.cmd_type = LTTNG_LIST_CHANNELS;
2242 ret = lttng_strncpy(lsm.session.name, handle->session_name,
2243 sizeof(lsm.session.name));
2244 if (ret) {
2245 ret = -LTTNG_ERR_INVALID;
2246 goto end;
2247 }
2248
2249 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
2250
2251 ret = lttng_ctl_ask_sessiond(&lsm, (void**) channels);
2252 if (ret < 0) {
2253 goto end;
2254 }
2255
2256 if (ret % channel_size) {
2257 ret = -LTTNG_ERR_UNK;
2258 free(*channels);
2259 *channels = NULL;
2260 goto end;
2261 }
2262 channel_count = (size_t) ret / channel_size;
2263
2264 /* Set extended info pointers */
2265 extended_at = ((void *) *channels) +
2266 channel_count * sizeof(struct lttng_channel);
2267 for (i = 0; i < channel_count; i++) {
2268 struct lttng_channel *chan = &(*channels)[i];
2269
2270 chan->attr.extended.ptr = extended_at;
2271 extended_at += sizeof(struct lttng_channel_extended);
2272 }
2273
2274 ret = (int) channel_count;
2275 end:
2276 return ret;
2277 }
2278
2279 /*
2280 * Ask the session daemon for all available events of a session channel.
2281 * Sets the contents of the events array.
2282 * Returns the number of lttng_event entries in events;
2283 * on error, returns a negative value.
2284 */
2285 int lttng_list_events(struct lttng_handle *handle,
2286 const char *channel_name, struct lttng_event **events)
2287 {
2288 int ret;
2289 struct lttcomm_session_msg lsm = {};
2290 const struct lttcomm_event_command_header *cmd_header = NULL;
2291 uint32_t nb_events, i;
2292 const void *comm_ext_at;
2293 struct lttng_dynamic_buffer listing;
2294 size_t storage_req;
2295 struct lttng_payload payload;
2296 struct lttng_payload payload_copy;
2297 struct lttng_payload_view lsm_view =
2298 lttng_payload_view_init_from_buffer(
2299 (const char *) &lsm, 0, sizeof(lsm));
2300 struct lttng_buffer_view cmd_header_view;
2301 struct lttng_buffer_view cmd_payload_view;
2302 struct lttng_buffer_view flat_events_view;
2303 struct lttng_buffer_view ext_view;
2304
2305 /* Safety check. An handle and channel name are mandatory */
2306 if (handle == NULL || channel_name == NULL) {
2307 ret = -LTTNG_ERR_INVALID;
2308 goto end;
2309 }
2310
2311 lttng_payload_init(&payload);
2312 lttng_payload_init(&payload_copy);
2313
2314 lsm.cmd_type = LTTNG_LIST_EVENTS;
2315 ret = lttng_strncpy(lsm.session.name, handle->session_name,
2316 sizeof(lsm.session.name));
2317 if (ret) {
2318 ret = -LTTNG_ERR_INVALID;
2319 goto end;
2320 }
2321
2322 ret = lttng_strncpy(lsm.u.list.channel_name, channel_name,
2323 sizeof(lsm.u.list.channel_name));
2324 if (ret) {
2325 ret = -LTTNG_ERR_INVALID;
2326 goto end;
2327 }
2328
2329 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
2330
2331 ret = lttng_ctl_ask_sessiond_payload(&lsm_view, &payload);
2332 if (ret < 0) {
2333 goto end;
2334 }
2335
2336 /*
2337 * A copy of the payload is performed since it will be
2338 * consumed twice. Consuming the same payload twice is invalid since
2339 * it will cause any received file descriptor to become "shared"
2340 * between different instances of the resulting objects.
2341 */
2342 ret = lttng_payload_copy(&payload, &payload_copy);
2343 if (ret) {
2344 ret = -LTTNG_ERR_NOMEM;
2345 goto end;
2346 }
2347
2348 cmd_header_view = lttng_buffer_view_from_dynamic_buffer(
2349 &payload.buffer, 0, sizeof(*cmd_header));
2350 if (!lttng_buffer_view_is_valid(&cmd_header_view)) {
2351 ret = -LTTNG_ERR_INVALID_PROTOCOL;
2352 goto end;
2353 }
2354
2355 cmd_header = (typeof(cmd_header)) cmd_header_view.data;
2356
2357 /* Set number of events and free command header */
2358 nb_events = cmd_header->nb_events;
2359 if (nb_events > INT_MAX) {
2360 ret = -LTTNG_ERR_OVERFLOW;
2361 goto end;
2362 }
2363
2364 cmd_payload_view = lttng_buffer_view_from_dynamic_buffer(
2365 &payload.buffer, sizeof(*cmd_header), -1);
2366
2367 /*
2368 * The buffer that is returned must contain a "flat" version of
2369 * the events that are returned. In other words, all pointers
2370 * within an lttng_event must point to a location within the returned
2371 * buffer so that the user may free everything by simply calling free()
2372 * on the returned buffer. This is needed in order to maintain API
2373 * compatibility.
2374 *
2375 * A first pass is performed to compute the size of the buffer that
2376 * must be allocated. A second pass is then performed to setup
2377 * the returned events so that their members always point within the
2378 * buffer.
2379 *
2380 * The layout of the returned buffer is as follows:
2381 * - struct lttng_event[nb_events],
2382 * - nb_events times the following:
2383 * - struct lttng_event_extended,
2384 * - flattened version of userspace_probe_location
2385 * - filter_expression
2386 * - exclusions
2387 * - padding to align to 64-bits
2388 */
2389 ext_view = lttng_buffer_view_from_view(&cmd_payload_view,
2390 nb_events * sizeof(struct lttng_event), -1);
2391 comm_ext_at = ext_view.data;
2392 storage_req = nb_events * sizeof(struct lttng_event);
2393 {
2394 struct lttng_payload_view payload_view =
2395 lttng_payload_view_from_payload(&payload, 0, -1);
2396
2397 for (i = 0; i < nb_events; i++) {
2398 const struct lttcomm_event_extended_header *ext_comm =
2399 (struct lttcomm_event_extended_header *)
2400 comm_ext_at;
2401 int probe_storage_req = 0;
2402
2403 comm_ext_at += sizeof(*ext_comm);
2404 comm_ext_at += ext_comm->filter_len;
2405 comm_ext_at += ext_comm->nb_exclusions *
2406 LTTNG_SYMBOL_NAME_LEN;
2407
2408 if (ext_comm->userspace_probe_location_len) {
2409 struct lttng_userspace_probe_location
2410 *probe_location = NULL;
2411 struct lttng_payload_view probe_location_view = lttng_payload_view_from_view(
2412 &payload_view,
2413 (const char *) comm_ext_at -
2414 payload_view.buffer.data,
2415 ext_comm->userspace_probe_location_len);
2416
2417 if (!lttng_payload_view_is_valid(&probe_location_view)) {
2418 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2419 goto end;
2420 }
2421
2422 /*
2423 * Create a temporary userspace probe location
2424 * to determine the size needed by a "flattened"
2425 * version of that same probe location.
2426 */
2427 ret = lttng_userspace_probe_location_create_from_payload(
2428 &probe_location_view,
2429 &probe_location);
2430 if (ret < 0) {
2431 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2432 goto end;
2433 }
2434
2435 ret = lttng_userspace_probe_location_flatten(
2436 probe_location, NULL);
2437 lttng_userspace_probe_location_destroy(
2438 probe_location);
2439 if (ret < 0) {
2440 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2441 goto end;
2442 }
2443
2444 probe_storage_req = ret;
2445 comm_ext_at += ext_comm->userspace_probe_location_len;
2446 }
2447
2448 storage_req += sizeof(struct lttng_event_extended);
2449 storage_req += ext_comm->filter_len;
2450 storage_req += ext_comm->nb_exclusions *
2451 LTTNG_SYMBOL_NAME_LEN;
2452 /* Padding to ensure the flat probe is aligned. */
2453 storage_req = ALIGN_TO(storage_req, sizeof(uint64_t));
2454 storage_req += probe_storage_req;
2455 }
2456 }
2457
2458 lttng_dynamic_buffer_init(&listing);
2459 /*
2460 * We must ensure that "listing" is never resized so as to preserve
2461 * the validity of the flattened objects.
2462 */
2463 ret = lttng_dynamic_buffer_set_capacity(&listing, storage_req);
2464 if (ret) {
2465 ret = -LTTNG_ERR_NOMEM;
2466 goto end;
2467 }
2468
2469 cmd_payload_view = lttng_buffer_view_from_dynamic_buffer(
2470 &payload_copy.buffer, sizeof(*cmd_header), -1);
2471 flat_events_view = lttng_buffer_view_from_view(&cmd_payload_view, 0,
2472 nb_events * sizeof(struct lttng_event));
2473 ret = lttng_dynamic_buffer_append_view(&listing, &flat_events_view);
2474 if (ret) {
2475 ret = -LTTNG_ERR_NOMEM;
2476 goto free_dynamic_buffer;
2477 }
2478
2479 ext_view = lttng_buffer_view_from_view(&cmd_payload_view,
2480 nb_events * sizeof(struct lttng_event), -1);
2481 comm_ext_at = ext_view.data;
2482
2483 {
2484 struct lttng_payload_view payload_copy_view =
2485 lttng_payload_view_from_payload(
2486 &payload_copy, 0, -1);
2487
2488 for (i = 0; i < nb_events; i++) {
2489 struct lttng_event *event = (typeof(event))(
2490 listing.data +
2491 (sizeof(struct lttng_event) * i));
2492 const struct lttcomm_event_extended_header *ext_comm =
2493 (typeof(ext_comm)) comm_ext_at;
2494 struct lttng_event_extended *event_extended =
2495 (typeof(event_extended))(listing.data +
2496 listing.size);
2497
2498 /* Insert struct lttng_event_extended. */
2499 ret = lttng_dynamic_buffer_set_size(&listing,
2500 listing.size + sizeof(*event_extended));
2501 if (ret) {
2502 ret = -LTTNG_ERR_NOMEM;
2503 goto free_dynamic_buffer;
2504 }
2505 event->extended.ptr = event_extended;
2506
2507 comm_ext_at += sizeof(*ext_comm);
2508
2509 /* Insert filter expression. */
2510 if (ext_comm->filter_len) {
2511 event_extended->filter_expression =
2512 listing.data + listing.size;
2513 ret = lttng_dynamic_buffer_append(&listing,
2514 comm_ext_at,
2515 ext_comm->filter_len);
2516 if (ret) {
2517 ret = -LTTNG_ERR_NOMEM;
2518 goto free_dynamic_buffer;
2519 }
2520 comm_ext_at += ext_comm->filter_len;
2521 }
2522
2523 /* Insert exclusions. */
2524 if (ext_comm->nb_exclusions) {
2525 event_extended->exclusions.count =
2526 ext_comm->nb_exclusions;
2527 event_extended->exclusions.strings =
2528 listing.data + listing.size;
2529
2530 ret = lttng_dynamic_buffer_append(&listing,
2531 comm_ext_at,
2532 ext_comm->nb_exclusions *
2533 LTTNG_SYMBOL_NAME_LEN);
2534 if (ret) {
2535 ret = -LTTNG_ERR_NOMEM;
2536 goto free_dynamic_buffer;
2537 }
2538 comm_ext_at += ext_comm->nb_exclusions *
2539 LTTNG_SYMBOL_NAME_LEN;
2540 }
2541
2542 /* Insert padding to align to 64-bits. */
2543 ret = lttng_dynamic_buffer_set_size(&listing,
2544 ALIGN_TO(listing.size,
2545 sizeof(uint64_t)));
2546 if (ret) {
2547 ret = -LTTNG_ERR_NOMEM;
2548 goto free_dynamic_buffer;
2549 }
2550
2551 /* Insert flattened userspace probe location. */
2552 if (ext_comm->userspace_probe_location_len) {
2553 struct lttng_userspace_probe_location
2554 *probe_location = NULL;
2555 struct lttng_payload_view probe_location_view = lttng_payload_view_from_view(
2556 &payload_copy_view,
2557 (const char *) comm_ext_at -
2558 payload_copy_view.buffer.data,
2559 ext_comm->userspace_probe_location_len);
2560
2561 if (!lttng_payload_view_is_valid(&probe_location_view)) {
2562 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2563 goto free_dynamic_buffer;
2564 }
2565
2566 ret = lttng_userspace_probe_location_create_from_payload(
2567 &probe_location_view,
2568 &probe_location);
2569 if (ret < 0) {
2570 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2571 goto free_dynamic_buffer;
2572 }
2573
2574 event_extended->probe_location = (struct lttng_userspace_probe_location
2575 *) (listing.data +
2576 listing.size);
2577 ret = lttng_userspace_probe_location_flatten(
2578 probe_location, &listing);
2579 lttng_userspace_probe_location_destroy(
2580 probe_location);
2581 if (ret < 0) {
2582 ret = -LTTNG_ERR_PROBE_LOCATION_INVAL;
2583 goto free_dynamic_buffer;
2584 }
2585
2586 comm_ext_at += ext_comm->userspace_probe_location_len;
2587 }
2588 }
2589 }
2590
2591 /* Don't reset listing buffer as we return its content. */
2592 *events = (struct lttng_event *) listing.data;
2593 lttng_dynamic_buffer_init(&listing);
2594 ret = (int) nb_events;
2595 free_dynamic_buffer:
2596 lttng_dynamic_buffer_reset(&listing);
2597 end:
2598 lttng_payload_reset(&payload);
2599 lttng_payload_reset(&payload_copy);
2600 return ret;
2601 }
2602
2603 /*
2604 * Sets the tracing_group variable with name.
2605 * This function allocates memory pointed to by tracing_group.
2606 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
2607 */
2608 int lttng_set_tracing_group(const char *name)
2609 {
2610 if (name == NULL) {
2611 return -LTTNG_ERR_INVALID;
2612 }
2613
2614 if (asprintf(&tracing_group, "%s", name) < 0) {
2615 return -LTTNG_ERR_FATAL;
2616 }
2617
2618 return 0;
2619 }
2620
2621 int lttng_calibrate(struct lttng_handle *handle,
2622 struct lttng_calibrate *calibrate)
2623 {
2624 /*
2625 * This command was removed in LTTng 2.9.
2626 */
2627 return -LTTNG_ERR_UND;
2628 }
2629
2630 /*
2631 * Set default channel attributes.
2632 * If either or both of the arguments are null, attr content is zeroe'd.
2633 */
2634 void lttng_channel_set_default_attr(struct lttng_domain *domain,
2635 struct lttng_channel_attr *attr)
2636 {
2637 struct lttng_channel_extended *extended;
2638
2639 /* Safety check */
2640 if (attr == NULL || domain == NULL) {
2641 return;
2642 }
2643
2644 extended = (struct lttng_channel_extended *) attr->extended.ptr;
2645 memset(attr, 0, sizeof(struct lttng_channel_attr));
2646
2647 /* Same for all domains. */
2648 attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
2649 attr->tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
2650 attr->tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT;
2651
2652 switch (domain->type) {
2653 case LTTNG_DOMAIN_KERNEL:
2654 attr->switch_timer_interval =
2655 DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
2656 attr->read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
2657 attr->subbuf_size = default_get_kernel_channel_subbuf_size();
2658 attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
2659 attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
2660 if (extended) {
2661 extended->monitor_timer_interval =
2662 DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER;
2663 extended->blocking_timeout =
2664 DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT;
2665 }
2666 break;
2667 case LTTNG_DOMAIN_UST:
2668 switch (domain->buf_type) {
2669 case LTTNG_BUFFER_PER_UID:
2670 attr->subbuf_size = default_get_ust_uid_channel_subbuf_size();
2671 attr->num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM;
2672 attr->output = DEFAULT_UST_UID_CHANNEL_OUTPUT;
2673 attr->switch_timer_interval =
2674 DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER;
2675 attr->read_timer_interval =
2676 DEFAULT_UST_UID_CHANNEL_READ_TIMER;
2677 if (extended) {
2678 extended->monitor_timer_interval =
2679 DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER;
2680 extended->blocking_timeout =
2681 DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT;
2682 }
2683 break;
2684 case LTTNG_BUFFER_PER_PID:
2685 default:
2686 attr->subbuf_size = default_get_ust_pid_channel_subbuf_size();
2687 attr->num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM;
2688 attr->output = DEFAULT_UST_PID_CHANNEL_OUTPUT;
2689 attr->switch_timer_interval =
2690 DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER;
2691 attr->read_timer_interval =
2692 DEFAULT_UST_PID_CHANNEL_READ_TIMER;
2693 if (extended) {
2694 extended->monitor_timer_interval =
2695 DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER;
2696 extended->blocking_timeout =
2697 DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT;
2698 }
2699 break;
2700 }
2701 default:
2702 /* Default behavior: leave set to 0. */
2703 break;
2704 }
2705
2706 attr->extended.ptr = extended;
2707 }
2708
2709 int lttng_channel_get_discarded_event_count(struct lttng_channel *channel,
2710 uint64_t *discarded_events)
2711 {
2712 int ret = 0;
2713 struct lttng_channel_extended *chan_ext;
2714
2715 if (!channel || !discarded_events) {
2716 ret = -LTTNG_ERR_INVALID;
2717 goto end;
2718 }
2719
2720 chan_ext = channel->attr.extended.ptr;
2721 if (!chan_ext) {
2722 /*
2723 * This can happen since the lttng_channel structure is
2724 * used for other tasks where this pointer is never set.
2725 */
2726 *discarded_events = 0;
2727 goto end;
2728 }
2729
2730 *discarded_events = chan_ext->discarded_events;
2731 end:
2732 return ret;
2733 }
2734
2735 int lttng_channel_get_lost_packet_count(struct lttng_channel *channel,
2736 uint64_t *lost_packets)
2737 {
2738 int ret = 0;
2739 struct lttng_channel_extended *chan_ext;
2740
2741 if (!channel || !lost_packets) {
2742 ret = -LTTNG_ERR_INVALID;
2743 goto end;
2744 }
2745
2746 chan_ext = channel->attr.extended.ptr;
2747 if (!chan_ext) {
2748 /*
2749 * This can happen since the lttng_channel structure is
2750 * used for other tasks where this pointer is never set.
2751 */
2752 *lost_packets = 0;
2753 goto end;
2754 }
2755
2756 *lost_packets = chan_ext->lost_packets;
2757 end:
2758 return ret;
2759 }
2760
2761 int lttng_channel_get_monitor_timer_interval(struct lttng_channel *chan,
2762 uint64_t *monitor_timer_interval)
2763 {
2764 int ret = 0;
2765
2766 if (!chan || !monitor_timer_interval) {
2767 ret = -LTTNG_ERR_INVALID;
2768 goto end;
2769 }
2770
2771 if (!chan->attr.extended.ptr) {
2772 ret = -LTTNG_ERR_INVALID;
2773 goto end;
2774 }
2775
2776 *monitor_timer_interval = ((struct lttng_channel_extended *)
2777 chan->attr.extended.ptr)->monitor_timer_interval;
2778 end:
2779 return ret;
2780 }
2781
2782 int lttng_channel_set_monitor_timer_interval(struct lttng_channel *chan,
2783 uint64_t monitor_timer_interval)
2784 {
2785 int ret = 0;
2786
2787 if (!chan || !chan->attr.extended.ptr) {
2788 ret = -LTTNG_ERR_INVALID;
2789 goto end;
2790 }
2791
2792 ((struct lttng_channel_extended *)
2793 chan->attr.extended.ptr)->monitor_timer_interval =
2794 monitor_timer_interval;
2795 end:
2796 return ret;
2797 }
2798
2799 int lttng_channel_get_blocking_timeout(struct lttng_channel *chan,
2800 int64_t *blocking_timeout)
2801 {
2802 int ret = 0;
2803
2804 if (!chan || !blocking_timeout) {
2805 ret = -LTTNG_ERR_INVALID;
2806 goto end;
2807 }
2808
2809 if (!chan->attr.extended.ptr) {
2810 ret = -LTTNG_ERR_INVALID;
2811 goto end;
2812 }
2813
2814 *blocking_timeout = ((struct lttng_channel_extended *)
2815 chan->attr.extended.ptr)->blocking_timeout;
2816 end:
2817 return ret;
2818 }
2819
2820 int lttng_channel_set_blocking_timeout(struct lttng_channel *chan,
2821 int64_t blocking_timeout)
2822 {
2823 int ret = 0;
2824 int64_t msec_timeout;
2825
2826 if (!chan || !chan->attr.extended.ptr) {
2827 ret = -LTTNG_ERR_INVALID;
2828 goto end;
2829 }
2830
2831 if (blocking_timeout < 0 && blocking_timeout != -1) {
2832 ret = -LTTNG_ERR_INVALID;
2833 goto end;
2834 }
2835
2836 /*
2837 * LTTng-ust's use of poll() to implement this timeout mechanism forces
2838 * us to accept a narrower range of values (msecs expressed as a signed
2839 * 32-bit integer).
2840 */
2841 msec_timeout = blocking_timeout / 1000;
2842 if (msec_timeout != (int32_t) msec_timeout) {
2843 ret = -LTTNG_ERR_INVALID;
2844 goto end;
2845 }
2846
2847 ((struct lttng_channel_extended *)
2848 chan->attr.extended.ptr)->blocking_timeout =
2849 blocking_timeout;
2850 end:
2851 return ret;
2852 }
2853
2854 /*
2855 * Check if session daemon is alive.
2856 *
2857 * Return 1 if alive or 0 if not.
2858 * On error returns a negative value.
2859 */
2860 int lttng_session_daemon_alive(void)
2861 {
2862 int ret;
2863
2864 ret = set_session_daemon_path();
2865 if (ret < 0) {
2866 /* Error. */
2867 return ret;
2868 }
2869
2870 if (*sessiond_sock_path == '\0') {
2871 /*
2872 * No socket path set. Weird error which means the constructor
2873 * was not called.
2874 */
2875 assert(0);
2876 }
2877
2878 ret = try_connect_sessiond(sessiond_sock_path);
2879 if (ret < 0) {
2880 /* Not alive. */
2881 return 0;
2882 }
2883
2884 /* Is alive. */
2885 return 1;
2886 }
2887
2888 /*
2889 * Set URL for a consumer for a session and domain.
2890 *
2891 * Return 0 on success, else a negative value.
2892 */
2893 int lttng_set_consumer_url(struct lttng_handle *handle,
2894 const char *control_url, const char *data_url)
2895 {
2896 int ret;
2897 ssize_t size;
2898 struct lttcomm_session_msg lsm;
2899 struct lttng_uri *uris = NULL;
2900
2901 if (handle == NULL || (control_url == NULL && data_url == NULL)) {
2902 ret = -LTTNG_ERR_INVALID;
2903 goto error;
2904 }
2905
2906 memset(&lsm, 0, sizeof(lsm));
2907
2908 lsm.cmd_type = LTTNG_SET_CONSUMER_URI;
2909
2910 ret = lttng_strncpy(lsm.session.name, handle->session_name,
2911 sizeof(lsm.session.name));
2912 if (ret) {
2913 ret = -LTTNG_ERR_INVALID;
2914 goto error;
2915 }
2916
2917 COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
2918
2919 size = uri_parse_str_urls(control_url, data_url, &uris);
2920 if (size < 0) {
2921 ret = -LTTNG_ERR_INVALID;
2922 goto error;
2923 }
2924
2925 lsm.u.uri.size = size;
2926
2927 ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, uris,
2928 sizeof(struct lttng_uri) * size, NULL);
2929
2930 free(uris);
2931 error:
2932 return ret;
2933 }
2934
2935 /*
2936 * [OBSOLETE]
2937 */
2938 int lttng_enable_consumer(struct lttng_handle *handle);
2939 int lttng_enable_consumer(struct lttng_handle *handle)
2940 {
2941 return -ENOSYS;
2942 }
2943
2944 /*
2945 * [OBSOLETE]
2946 */
2947 int lttng_disable_consumer(struct lttng_handle *handle);
2948 int lttng_disable_consumer(struct lttng_handle *handle)
2949 {
2950 return -ENOSYS;
2951 }
2952
2953 /*
2954 * [OBSOLETE]
2955 */
2956 int _lttng_create_session_ext(const char *name, const char *url,
2957 const char *datetime);
2958 int _lttng_create_session_ext(const char *name, const char *url,
2959 const char *datetime)
2960 {
2961 return -ENOSYS;
2962 }
2963
2964 /*
2965 * For a given session name, this call checks if the data is ready to be read
2966 * or is still being extracted by the consumer(s) hence not ready to be used by
2967 * any readers.
2968 */
2969 int lttng_data_pending(const char *session_name)
2970 {
2971 int ret;
2972 struct lttcomm_session_msg lsm;
2973 uint8_t *pending = NULL;
2974
2975 if (session_name == NULL) {
2976 return -LTTNG_ERR_INVALID;
2977 }
2978
2979 memset(&lsm, 0, sizeof(lsm));
2980 lsm.cmd_type = LTTNG_DATA_PENDING;
2981
2982 ret = lttng_strncpy(lsm.session.name, session_name,
2983 sizeof(lsm.session.name));
2984 if (ret) {
2985 ret = -LTTNG_ERR_INVALID;
2986 goto end;
2987 }
2988
2989 ret = lttng_ctl_ask_sessiond(&lsm, (void **) &pending);
2990 if (ret < 0) {
2991 goto end;
2992 } else if (ret != 1) {
2993 /* Unexpected payload size */
2994 ret = -LTTNG_ERR_INVALID;
2995 goto end;
2996 } else if (!pending) {
2997 /* Internal error. */
2998 ret = -LTTNG_ERR_UNK;
2999 goto end;
3000 }
3001
3002 ret = (int) *pending;
3003 end:
3004 free(pending);
3005 return ret;
3006 }
3007
3008 /*
3009 * Regenerate the metadata for a session.
3010 * Return 0 on success, a negative error code on error.
3011 */
3012 int lttng_regenerate_metadata(const char *session_name)
3013 {
3014 int ret;
3015 struct lttcomm_session_msg lsm;
3016
3017 if (!session_name) {
3018 ret = -LTTNG_ERR_INVALID;
3019 goto end;
3020 }
3021
3022 memset(&lsm, 0, sizeof(lsm));
3023 lsm.cmd_type = LTTNG_REGENERATE_METADATA;
3024
3025 ret = lttng_strncpy(lsm.session.name, session_name,
3026 sizeof(lsm.session.name));
3027 if (ret) {
3028 ret = -LTTNG_ERR_INVALID;
3029 goto end;
3030 }
3031
3032 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
3033 if (ret < 0) {
3034 goto end;
3035 }
3036
3037 ret = 0;
3038 end:
3039 return ret;
3040 }
3041
3042 /*
3043 * Deprecated, replaced by lttng_regenerate_metadata.
3044 */
3045 int lttng_metadata_regenerate(const char *session_name)
3046 {
3047 return lttng_regenerate_metadata(session_name);
3048 }
3049
3050 /*
3051 * Regenerate the statedump of a session.
3052 * Return 0 on success, a negative error code on error.
3053 */
3054 int lttng_regenerate_statedump(const char *session_name)
3055 {
3056 int ret;
3057 struct lttcomm_session_msg lsm;
3058
3059 if (!session_name) {
3060 ret = -LTTNG_ERR_INVALID;
3061 goto end;
3062 }
3063
3064 memset(&lsm, 0, sizeof(lsm));
3065 lsm.cmd_type = LTTNG_REGENERATE_STATEDUMP;
3066
3067 ret = lttng_strncpy(lsm.session.name, session_name,
3068 sizeof(lsm.session.name));
3069 if (ret) {
3070 ret = -LTTNG_ERR_INVALID;
3071 goto end;
3072 }
3073
3074 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
3075 if (ret < 0) {
3076 goto end;
3077 }
3078
3079 ret = 0;
3080 end:
3081 return ret;
3082 }
3083
3084 int lttng_register_trigger(struct lttng_trigger *trigger)
3085 {
3086 int ret;
3087 struct lttcomm_session_msg lsm = {
3088 .cmd_type = LTTNG_REGISTER_TRIGGER,
3089 };
3090 struct lttcomm_session_msg *message_lsm;
3091 struct lttng_payload message;
3092 struct lttng_payload reply;
3093 struct lttng_trigger *reply_trigger = NULL;
3094 enum lttng_domain_type domain_type;
3095 const struct lttng_credentials user_creds = {
3096 .uid = LTTNG_OPTIONAL_INIT_VALUE(geteuid()),
3097 .gid = LTTNG_OPTIONAL_INIT_UNSET,
3098 };
3099
3100
3101 lttng_payload_init(&message);
3102 lttng_payload_init(&reply);
3103
3104 if (!trigger) {
3105 ret = -LTTNG_ERR_INVALID;
3106 goto end;
3107 }
3108
3109 if (!trigger->creds.uid.is_set) {
3110 /* Use the client's credentials as the trigger credentials. */
3111 lttng_trigger_set_credentials(trigger, &user_creds);
3112 } else {
3113 /*
3114 * Validate that either the current trigger credentials and the
3115 * client credentials are identical or that the current user is
3116 * root. The root user can register, unregister triggers for
3117 * himself and other users.
3118 *
3119 * This check is also present on the sessiond side, using the
3120 * credentials passed on the socket. These check are all
3121 * "safety" checks.
3122 */
3123 const struct lttng_credentials *trigger_creds =
3124 lttng_trigger_get_credentials(trigger);
3125
3126 if (!lttng_credentials_is_equal_uid(trigger_creds, &user_creds)) {
3127 if (lttng_credentials_get_uid(&user_creds) != 0) {
3128 ret = -LTTNG_ERR_EPERM;
3129 goto end;
3130 }
3131 }
3132 }
3133
3134 if (!lttng_trigger_validate(trigger)) {
3135 ret = -LTTNG_ERR_INVALID_TRIGGER;
3136 goto end;
3137 }
3138
3139 domain_type = lttng_trigger_get_underlying_domain_type_restriction(
3140 trigger);
3141
3142 lsm.domain.type = domain_type;
3143
3144 ret = lttng_dynamic_buffer_append(&message.buffer, &lsm, sizeof(lsm));
3145 if (ret) {
3146 ret = -LTTNG_ERR_NOMEM;
3147 goto end;
3148 }
3149
3150 ret = lttng_trigger_serialize(trigger, &message);
3151 if (ret < 0) {
3152 ret = -LTTNG_ERR_UNK;
3153 goto end;
3154 }
3155
3156 /*
3157 * This is needed to populate the trigger object size for the command
3158 * header.
3159 */
3160 message_lsm = (struct lttcomm_session_msg *) message.buffer.data;
3161
3162 message_lsm->u.trigger.length = (uint32_t) message.buffer.size - sizeof(lsm);
3163
3164 {
3165 struct lttng_payload_view message_view =
3166 lttng_payload_view_from_payload(
3167 &message, 0, -1);
3168
3169 message_lsm->fd_count = lttng_payload_view_get_fd_handle_count(
3170 &message_view);
3171 ret = lttng_ctl_ask_sessiond_payload(&message_view, &reply);
3172 if (ret < 0) {
3173 goto end;
3174 }
3175 }
3176
3177 {
3178 struct lttng_payload_view reply_view =
3179 lttng_payload_view_from_payload(
3180 &reply, 0, reply.buffer.size);
3181
3182 ret = lttng_trigger_create_from_payload(
3183 &reply_view, &reply_trigger);
3184 if (ret < 0) {
3185 ret = -LTTNG_ERR_FATAL;
3186 goto end;
3187 }
3188 }
3189
3190 ret = lttng_trigger_assign_name(trigger, reply_trigger);
3191 if (ret < 0) {
3192 ret = -LTTNG_ERR_FATAL;
3193 goto end;
3194 }
3195
3196 ret = 0;
3197 end:
3198 lttng_payload_reset(&message);
3199 lttng_payload_reset(&reply);
3200 lttng_trigger_destroy(reply_trigger);
3201 return ret;
3202 }
3203
3204 int lttng_unregister_trigger(const struct lttng_trigger *trigger)
3205 {
3206 int ret;
3207 struct lttcomm_session_msg lsm;
3208 struct lttcomm_session_msg *message_lsm;
3209 struct lttng_payload message;
3210 struct lttng_payload reply;
3211 struct lttng_trigger *copy = NULL;
3212 const struct lttng_credentials user_creds = {
3213 .uid = LTTNG_OPTIONAL_INIT_VALUE(geteuid()),
3214 .gid = LTTNG_OPTIONAL_INIT_UNSET,
3215 };
3216
3217 lttng_payload_init(&message);
3218 lttng_payload_init(&reply);
3219
3220 if (!trigger) {
3221 ret = -LTTNG_ERR_INVALID;
3222 goto end;
3223 }
3224
3225 copy = lttng_trigger_copy(trigger);
3226 if (!copy) {
3227 ret = -LTTNG_ERR_UNK;
3228 goto end;
3229 }
3230
3231 if (!copy->creds.uid.is_set) {
3232 /* Use the client credentials as the trigger credentials */
3233 lttng_trigger_set_credentials(copy, &user_creds);
3234 } else {
3235 /*
3236 * Validate that either the current trigger credentials and the
3237 * client credentials are identical or that the current user is
3238 * root. The root user can register, unregister triggers for
3239 * himself and other users.
3240 *
3241 * This check is also present on the sessiond side, using the
3242 * credentials passed on the socket. These check are all
3243 * "safety" checks.
3244 */
3245 const struct lttng_credentials *trigger_creds =
3246 lttng_trigger_get_credentials(copy);
3247 if (!lttng_credentials_is_equal_uid(trigger_creds, &user_creds)) {
3248 if (lttng_credentials_get_uid(&user_creds) != 0) {
3249 ret = -LTTNG_ERR_EPERM;
3250 goto end;
3251 }
3252 }
3253 }
3254
3255 if (!lttng_trigger_validate(copy)) {
3256 ret = -LTTNG_ERR_INVALID_TRIGGER;
3257 goto end;
3258 }
3259
3260 memset(&lsm, 0, sizeof(lsm));
3261 lsm.cmd_type = LTTNG_UNREGISTER_TRIGGER;
3262
3263 ret = lttng_dynamic_buffer_append(&message.buffer, &lsm, sizeof(lsm));
3264 if (ret) {
3265 ret = -LTTNG_ERR_NOMEM;
3266 goto end;
3267 }
3268
3269 /*
3270 * This is needed to populate the trigger object size for the command
3271 * header and number of fds sent.
3272 */
3273 message_lsm = (struct lttcomm_session_msg *) message.buffer.data;
3274
3275 ret = lttng_trigger_serialize(copy, &message);
3276 if (ret < 0) {
3277 ret = -LTTNG_ERR_UNK;
3278 goto end;
3279 }
3280
3281 message_lsm->u.trigger.length = (uint32_t) message.buffer.size - sizeof(lsm);
3282
3283 {
3284 struct lttng_payload_view message_view =
3285 lttng_payload_view_from_payload(
3286 &message, 0, -1);
3287
3288 /*
3289 * Update the message header with the number of fd that will be
3290 * sent.
3291 */
3292 message_lsm->fd_count = lttng_payload_view_get_fd_handle_count(
3293 &message_view);
3294
3295 ret = lttng_ctl_ask_sessiond_payload(&message_view, &reply);
3296 if (ret < 0) {
3297 goto end;
3298 }
3299 }
3300
3301 ret = 0;
3302 end:
3303 lttng_trigger_destroy(copy);
3304 lttng_payload_reset(&message);
3305 lttng_payload_reset(&reply);
3306 return ret;
3307 }
3308
3309 /*
3310 * Ask the session daemon for all registered triggers for the current user.
3311 *
3312 * Allocates and return an lttng_triggers set.
3313 * On error, returns a suitable lttng_error_code.
3314 */
3315 enum lttng_error_code lttng_list_triggers(struct lttng_triggers **triggers)
3316 {
3317 int ret;
3318 enum lttng_error_code ret_code = LTTNG_OK;
3319 struct lttcomm_session_msg lsm = { .cmd_type = LTTNG_LIST_TRIGGERS };
3320 struct lttng_triggers *local_triggers = NULL;
3321 struct lttng_payload reply;
3322 struct lttng_payload_view lsm_view =
3323 lttng_payload_view_init_from_buffer(
3324 (const char *) &lsm, 0, sizeof(lsm));
3325
3326 lttng_payload_init(&reply);
3327
3328 ret = lttng_ctl_ask_sessiond_payload(&lsm_view, &reply);
3329 if (ret < 0) {
3330 ret_code = (enum lttng_error_code) -ret;
3331 goto end;
3332 }
3333
3334 {
3335 struct lttng_payload_view reply_view =
3336 lttng_payload_view_from_payload(
3337 &reply, 0, reply.buffer.size);
3338
3339 ret = lttng_triggers_create_from_payload(
3340 &reply_view, &local_triggers);
3341 if (ret < 0) {
3342 ret_code = LTTNG_ERR_FATAL;
3343 goto end;
3344 }
3345 }
3346
3347 *triggers = local_triggers;
3348 local_triggers = NULL;
3349 end:
3350 lttng_payload_reset(&reply);
3351 lttng_triggers_destroy(local_triggers);
3352 return ret_code;
3353 }
3354
3355 /*
3356 * lib constructor.
3357 */
3358 static void __attribute__((constructor)) init(void)
3359 {
3360 /* Set default session group */
3361 lttng_set_tracing_group(DEFAULT_TRACING_GROUP);
3362 }
3363
3364 /*
3365 * lib destructor.
3366 */
3367 static void __attribute__((destructor)) lttng_ctl_exit(void)
3368 {
3369 free(tracing_group);
3370 }
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