a92bf39125b287528d202d9160e09d7b7c7462f2
[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.c
1 /*
2 * liblttngctl.c
3 *
4 * Linux Trace Toolkit Control Library
5 *
6 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
7 *
8 * This library is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU Lesser General Public License, version 2.1 only,
10 * as published by the Free Software Foundation.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #define _GNU_SOURCE
23 #include <assert.h>
24 #include <grp.h>
25 #include <errno.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <unistd.h>
30
31 #include <common/common.h>
32 #include <common/defaults.h>
33 #include <common/sessiond-comm/sessiond-comm.h>
34 #include <common/uri.h>
35 #include <common/utils.h>
36 #include <lttng/lttng.h>
37 #include <lttng/health-internal.h>
38
39 #include "filter/filter-ast.h"
40 #include "filter/filter-parser.h"
41 #include "filter/filter-bytecode.h"
42 #include "filter/memstream.h"
43 #include "lttng-ctl-helper.h"
44
45 #ifdef DEBUG
46 static const int print_xml = 1;
47 #define dbg_printf(fmt, args...) \
48 printf("[debug liblttng-ctl] " fmt, ## args)
49 #else
50 static const int print_xml = 0;
51 #define dbg_printf(fmt, args...) \
52 do { \
53 /* do nothing but check printf format */ \
54 if (0) \
55 printf("[debug liblttnctl] " fmt, ## args); \
56 } while (0)
57 #endif
58
59
60 /* Socket to session daemon for communication */
61 static int sessiond_socket;
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
78 /*
79 * Copy string from src to dst and enforce null terminated byte.
80 */
81 LTTNG_HIDDEN
82 void lttng_ctl_copy_string(char *dst, const char *src, size_t len)
83 {
84 if (src && dst) {
85 strncpy(dst, src, len);
86 /* Enforce the NULL terminated byte */
87 dst[len - 1] = '\0';
88 } else if (dst) {
89 dst[0] = '\0';
90 }
91 }
92
93 /*
94 * Copy domain to lttcomm_session_msg domain.
95 *
96 * If domain is unknown, default domain will be the kernel.
97 */
98 LTTNG_HIDDEN
99 void lttng_ctl_copy_lttng_domain(struct lttng_domain *dst,
100 struct lttng_domain *src)
101 {
102 if (src && dst) {
103 switch (src->type) {
104 case LTTNG_DOMAIN_KERNEL:
105 case LTTNG_DOMAIN_UST:
106 case LTTNG_DOMAIN_JUL:
107 memcpy(dst, src, sizeof(struct lttng_domain));
108 break;
109 default:
110 memset(dst, 0, sizeof(struct lttng_domain));
111 break;
112 }
113 }
114 }
115
116 /*
117 * Send lttcomm_session_msg to the session daemon.
118 *
119 * On success, returns the number of bytes sent (>=0)
120 * On error, returns -1
121 */
122 static int send_session_msg(struct lttcomm_session_msg *lsm)
123 {
124 int ret;
125
126 if (!connected) {
127 ret = -LTTNG_ERR_NO_SESSIOND;
128 goto end;
129 }
130
131 DBG("LSM cmd type : %d", lsm->cmd_type);
132
133 ret = lttcomm_send_creds_unix_sock(sessiond_socket, lsm,
134 sizeof(struct lttcomm_session_msg));
135 if (ret < 0) {
136 ret = -LTTNG_ERR_FATAL;
137 }
138
139 end:
140 return ret;
141 }
142
143 /*
144 * Send var len data to the session daemon.
145 *
146 * On success, returns the number of bytes sent (>=0)
147 * On error, returns -1
148 */
149 static int send_session_varlen(void *data, size_t len)
150 {
151 int ret;
152
153 if (!connected) {
154 ret = -LTTNG_ERR_NO_SESSIOND;
155 goto end;
156 }
157
158 if (!data || !len) {
159 ret = 0;
160 goto end;
161 }
162
163 ret = lttcomm_send_unix_sock(sessiond_socket, data, len);
164 if (ret < 0) {
165 ret = -LTTNG_ERR_FATAL;
166 }
167
168 end:
169 return ret;
170 }
171
172 /*
173 * Receive data from the sessiond socket.
174 *
175 * On success, returns the number of bytes received (>=0)
176 * On error, returns -1 (recvmsg() error) or -ENOTCONN
177 */
178 static int recv_data_sessiond(void *buf, size_t len)
179 {
180 int ret;
181
182 if (!connected) {
183 ret = -LTTNG_ERR_NO_SESSIOND;
184 goto end;
185 }
186
187 ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len);
188 if (ret < 0) {
189 ret = -LTTNG_ERR_FATAL;
190 }
191
192 end:
193 return ret;
194 }
195
196 /*
197 * Check if we are in the specified group.
198 *
199 * If yes return 1, else return -1.
200 */
201 LTTNG_HIDDEN
202 int lttng_check_tracing_group(void)
203 {
204 struct group *grp_tracing; /* no free(). See getgrnam(3) */
205 gid_t *grp_list;
206 int grp_list_size, grp_id, i;
207 int ret = -1;
208 const char *grp_name = tracing_group;
209
210 /* Get GID of group 'tracing' */
211 grp_tracing = getgrnam(grp_name);
212 if (!grp_tracing) {
213 /* If grp_tracing is NULL, the group does not exist. */
214 goto end;
215 }
216
217 /* Get number of supplementary group IDs */
218 grp_list_size = getgroups(0, NULL);
219 if (grp_list_size < 0) {
220 perror("getgroups");
221 goto end;
222 }
223
224 /* Alloc group list of the right size */
225 grp_list = malloc(grp_list_size * sizeof(gid_t));
226 if (!grp_list) {
227 perror("malloc");
228 goto end;
229 }
230 grp_id = getgroups(grp_list_size, grp_list);
231 if (grp_id < 0) {
232 perror("getgroups");
233 goto free_list;
234 }
235
236 for (i = 0; i < grp_list_size; i++) {
237 if (grp_list[i] == grp_tracing->gr_gid) {
238 ret = 1;
239 break;
240 }
241 }
242
243 free_list:
244 free(grp_list);
245
246 end:
247 return ret;
248 }
249
250 /*
251 * Try connect to session daemon with sock_path.
252 *
253 * Return 0 on success, else -1
254 */
255 static int try_connect_sessiond(const char *sock_path)
256 {
257 int ret;
258
259 /* If socket exist, we check if the daemon listens for connect. */
260 ret = access(sock_path, F_OK);
261 if (ret < 0) {
262 /* Not alive */
263 goto error;
264 }
265
266 ret = lttcomm_connect_unix_sock(sock_path);
267 if (ret < 0) {
268 /* Not alive */
269 goto error;
270 }
271
272 ret = lttcomm_close_unix_sock(ret);
273 if (ret < 0) {
274 perror("lttcomm_close_unix_sock");
275 }
276
277 return 0;
278
279 error:
280 return -1;
281 }
282
283 /*
284 * Set sessiond socket path by putting it in the global sessiond_sock_path
285 * variable.
286 *
287 * Returns 0 on success, negative value on failure (the sessiond socket path
288 * is somehow too long or ENOMEM).
289 */
290 static int set_session_daemon_path(void)
291 {
292 int in_tgroup = 0; /* In tracing group */
293 uid_t uid;
294
295 uid = getuid();
296
297 if (uid != 0) {
298 /* Are we in the tracing group ? */
299 in_tgroup = lttng_check_tracing_group();
300 }
301
302 if ((uid == 0) || in_tgroup) {
303 lttng_ctl_copy_string(sessiond_sock_path,
304 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, sizeof(sessiond_sock_path));
305 }
306
307 if (uid != 0) {
308 int ret;
309
310 if (in_tgroup) {
311 /* Tracing group */
312 ret = try_connect_sessiond(sessiond_sock_path);
313 if (ret >= 0) {
314 goto end;
315 }
316 /* Global session daemon not available... */
317 }
318 /* ...or not in tracing group (and not root), default */
319
320 /*
321 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
322 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
323 */
324 ret = snprintf(sessiond_sock_path, sizeof(sessiond_sock_path),
325 DEFAULT_HOME_CLIENT_UNIX_SOCK, utils_get_home_dir());
326 if ((ret < 0) || (ret >= sizeof(sessiond_sock_path))) {
327 goto error;
328 }
329 }
330 end:
331 return 0;
332
333 error:
334 return -1;
335 }
336
337 /*
338 * Connect to the LTTng session daemon.
339 *
340 * On success, return 0. On error, return -1.
341 */
342 static int connect_sessiond(void)
343 {
344 int ret;
345
346 /* Don't try to connect if already connected. */
347 if (connected) {
348 return 0;
349 }
350
351 ret = set_session_daemon_path();
352 if (ret < 0) {
353 goto error;
354 }
355
356 /* Connect to the sesssion daemon */
357 ret = lttcomm_connect_unix_sock(sessiond_sock_path);
358 if (ret < 0) {
359 goto error;
360 }
361
362 sessiond_socket = ret;
363 connected = 1;
364
365 return 0;
366
367 error:
368 return -1;
369 }
370
371 /*
372 * Clean disconnect from the session daemon.
373 * On success, return 0. On error, return -1.
374 */
375 static int disconnect_sessiond(void)
376 {
377 int ret = 0;
378
379 if (connected) {
380 ret = lttcomm_close_unix_sock(sessiond_socket);
381 sessiond_socket = 0;
382 connected = 0;
383 }
384
385 return ret;
386 }
387
388 /*
389 * Ask the session daemon a specific command and put the data into buf.
390 * Takes extra var. len. data as input to send to the session daemon.
391 *
392 * Return size of data (only payload, not header) or a negative error code.
393 */
394 LTTNG_HIDDEN
395 int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg *lsm,
396 void *vardata, size_t varlen, void **buf)
397 {
398 int ret;
399 size_t size;
400 void *data = NULL;
401 struct lttcomm_lttng_msg llm;
402
403 ret = connect_sessiond();
404 if (ret < 0) {
405 ret = -LTTNG_ERR_NO_SESSIOND;
406 goto end;
407 }
408
409 /* Send command to session daemon */
410 ret = send_session_msg(lsm);
411 if (ret < 0) {
412 /* Ret value is a valid lttng error code. */
413 goto end;
414 }
415 /* Send var len data */
416 ret = send_session_varlen(vardata, varlen);
417 if (ret < 0) {
418 /* Ret value is a valid lttng error code. */
419 goto end;
420 }
421
422 /* Get header from data transmission */
423 ret = recv_data_sessiond(&llm, sizeof(llm));
424 if (ret < 0) {
425 /* Ret value is a valid lttng error code. */
426 goto end;
427 }
428
429 /* Check error code if OK */
430 if (llm.ret_code != LTTNG_OK) {
431 ret = -llm.ret_code;
432 goto end;
433 }
434
435 size = llm.data_size;
436 if (size == 0) {
437 /* If client free with size 0 */
438 if (buf != NULL) {
439 *buf = NULL;
440 }
441 ret = 0;
442 goto end;
443 }
444
445 data = (void*) malloc(size);
446
447 /* Get payload data */
448 ret = recv_data_sessiond(data, size);
449 if (ret < 0) {
450 free(data);
451 goto end;
452 }
453
454 /*
455 * Extra protection not to dereference a NULL pointer. If buf is NULL at
456 * this point, an error is returned and data is freed.
457 */
458 if (buf == NULL) {
459 ret = -LTTNG_ERR_INVALID;
460 free(data);
461 goto end;
462 }
463
464 *buf = data;
465 ret = size;
466
467 end:
468 disconnect_sessiond();
469 return ret;
470 }
471
472 /*
473 * Create lttng handle and return pointer.
474 * The returned pointer will be NULL in case of malloc() error.
475 */
476 struct lttng_handle *lttng_create_handle(const char *session_name,
477 struct lttng_domain *domain)
478 {
479 struct lttng_handle *handle = NULL;
480
481 if (domain == NULL) {
482 goto end;
483 }
484
485 handle = malloc(sizeof(struct lttng_handle));
486 if (handle == NULL) {
487 PERROR("malloc handle");
488 goto end;
489 }
490
491 /* Copy session name */
492 lttng_ctl_copy_string(handle->session_name, session_name,
493 sizeof(handle->session_name));
494
495 /* Copy lttng domain */
496 lttng_ctl_copy_lttng_domain(&handle->domain, domain);
497
498 end:
499 return handle;
500 }
501
502 /*
503 * Destroy handle by free(3) the pointer.
504 */
505 void lttng_destroy_handle(struct lttng_handle *handle)
506 {
507 free(handle);
508 }
509
510 /*
511 * Register an outside consumer.
512 * Returns size of returned session payload data or a negative error code.
513 */
514 int lttng_register_consumer(struct lttng_handle *handle,
515 const char *socket_path)
516 {
517 struct lttcomm_session_msg lsm;
518
519 if (handle == NULL || socket_path == NULL) {
520 return -LTTNG_ERR_INVALID;
521 }
522
523 memset(&lsm, 0, sizeof(lsm));
524 lsm.cmd_type = LTTNG_REGISTER_CONSUMER;
525 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
526 sizeof(lsm.session.name));
527 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
528
529 lttng_ctl_copy_string(lsm.u.reg.path, socket_path, sizeof(lsm.u.reg.path));
530
531 return lttng_ctl_ask_sessiond(&lsm, NULL);
532 }
533
534 /*
535 * Start tracing for all traces of the session.
536 * Returns size of returned session payload data or a negative error code.
537 */
538 int lttng_start_tracing(const char *session_name)
539 {
540 struct lttcomm_session_msg lsm;
541
542 if (session_name == NULL) {
543 return -LTTNG_ERR_INVALID;
544 }
545
546 memset(&lsm, 0, sizeof(lsm));
547 lsm.cmd_type = LTTNG_START_TRACE;
548
549 lttng_ctl_copy_string(lsm.session.name, session_name,
550 sizeof(lsm.session.name));
551
552 return lttng_ctl_ask_sessiond(&lsm, NULL);
553 }
554
555 /*
556 * Stop tracing for all traces of the session.
557 */
558 static int _lttng_stop_tracing(const char *session_name, int wait)
559 {
560 int ret, data_ret;
561 struct lttcomm_session_msg lsm;
562
563 if (session_name == NULL) {
564 return -LTTNG_ERR_INVALID;
565 }
566
567 memset(&lsm, 0, sizeof(lsm));
568 lsm.cmd_type = LTTNG_STOP_TRACE;
569
570 lttng_ctl_copy_string(lsm.session.name, session_name,
571 sizeof(lsm.session.name));
572
573 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
574 if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
575 goto error;
576 }
577
578 if (!wait) {
579 goto end;
580 }
581
582 /* Check for data availability */
583 do {
584 data_ret = lttng_data_pending(session_name);
585 if (data_ret < 0) {
586 /* Return the data available call error. */
587 ret = data_ret;
588 goto error;
589 }
590
591 /*
592 * Data sleep time before retrying (in usec). Don't sleep if the call
593 * returned value indicates availability.
594 */
595 if (data_ret) {
596 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME);
597 }
598 } while (data_ret != 0);
599
600 end:
601 error:
602 return ret;
603 }
604
605 /*
606 * Stop tracing and wait for data availability.
607 */
608 int lttng_stop_tracing(const char *session_name)
609 {
610 return _lttng_stop_tracing(session_name, 1);
611 }
612
613 /*
614 * Stop tracing but _don't_ wait for data availability.
615 */
616 int lttng_stop_tracing_no_wait(const char *session_name)
617 {
618 return _lttng_stop_tracing(session_name, 0);
619 }
620
621 /*
622 * Add context to a channel.
623 *
624 * If the given channel is NULL, add the contexts to all channels.
625 * The event_name param is ignored.
626 *
627 * Returns the size of the returned payload data or a negative error code.
628 */
629 int lttng_add_context(struct lttng_handle *handle,
630 struct lttng_event_context *ctx, const char *event_name,
631 const char *channel_name)
632 {
633 struct lttcomm_session_msg lsm;
634
635 /* Safety check. Both are mandatory */
636 if (handle == NULL || ctx == NULL) {
637 return -LTTNG_ERR_INVALID;
638 }
639
640 memset(&lsm, 0, sizeof(lsm));
641
642 lsm.cmd_type = LTTNG_ADD_CONTEXT;
643
644 /* If no channel name, send empty string. */
645 if (channel_name == NULL) {
646 lttng_ctl_copy_string(lsm.u.context.channel_name, "",
647 sizeof(lsm.u.context.channel_name));
648 } else {
649 lttng_ctl_copy_string(lsm.u.context.channel_name, channel_name,
650 sizeof(lsm.u.context.channel_name));
651 }
652
653 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
654
655 memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context));
656
657 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
658 sizeof(lsm.session.name));
659
660 return lttng_ctl_ask_sessiond(&lsm, NULL);
661 }
662
663 /*
664 * Enable event(s) for a channel.
665 * If no event name is specified, all events are enabled.
666 * If no channel name is specified, the default 'channel0' is used.
667 * Returns size of returned session payload data or a negative error code.
668 */
669 int lttng_enable_event(struct lttng_handle *handle,
670 struct lttng_event *ev, const char *channel_name)
671 {
672 return lttng_enable_event_with_exclusions(handle, ev, channel_name,
673 NULL, 0, NULL);
674 }
675
676 /*
677 * Create or enable an event with a filter expression.
678 *
679 * Return negative error value on error.
680 * Return size of returned session payload data if OK.
681 */
682 int lttng_enable_event_with_filter(struct lttng_handle *handle,
683 struct lttng_event *event, const char *channel_name,
684 const char *filter_expression)
685 {
686 return lttng_enable_event_with_exclusions(handle, event, channel_name,
687 filter_expression, 0, NULL);
688 }
689
690 /*
691 * Depending on the event, return a newly allocated JUL filter expression or
692 * NULL if not applicable.
693 *
694 * An event with NO loglevel and the name is * will return NULL.
695 */
696 static char *set_jul_filter(const char *filter, struct lttng_event *ev)
697 {
698 int err;
699 char *jul_filter = NULL;
700
701 assert(ev);
702
703 /* Don't add filter for the '*' event. */
704 if (ev->name[0] != '*') {
705 if (filter) {
706 err = asprintf(&jul_filter, "%s && logger_name == \"%s\"", filter,
707 ev->name);
708 } else {
709 err = asprintf(&jul_filter, "logger_name == \"%s\"", ev->name);
710 }
711 if (err < 0) {
712 PERROR("asprintf");
713 goto error;
714 }
715 }
716
717 /* Add loglevel filtering if any for the JUL domain. */
718 if (ev->loglevel_type != LTTNG_EVENT_LOGLEVEL_ALL) {
719 char *op;
720
721 if (ev->loglevel_type == LTTNG_EVENT_LOGLEVEL_RANGE) {
722 op = ">=";
723 } else {
724 op = "==";
725 }
726
727 if (filter || jul_filter) {
728 char *new_filter;
729
730 err = asprintf(&new_filter, "%s && int_loglevel %s %d",
731 jul_filter ? jul_filter : filter, op,
732 ev->loglevel);
733 if (jul_filter) {
734 free(jul_filter);
735 }
736 jul_filter = new_filter;
737 } else {
738 err = asprintf(&jul_filter, "int_loglevel %s %d", op,
739 ev->loglevel);
740 }
741 if (err < 0) {
742 PERROR("asprintf");
743 goto error;
744 }
745 }
746
747 return jul_filter;
748 error:
749 free(jul_filter);
750 return NULL;
751 }
752
753 /*
754 * Generate the filter bytecode from a give filter expression string. Put the
755 * newly allocated parser context in ctxp and populate the lsm object with the
756 * expression len.
757 *
758 * Return 0 on success else a LTTNG_ERR_* code and ctxp is untouched.
759 */
760 static int generate_filter(char *filter_expression,
761 struct lttcomm_session_msg *lsm, struct filter_parser_ctx **ctxp)
762 {
763 int ret;
764 struct filter_parser_ctx *ctx = NULL;
765 FILE *fmem = NULL;
766
767 assert(filter_expression);
768 assert(lsm);
769 assert(ctxp);
770
771 /*
772 * Casting const to non-const, as the underlying function will use it in
773 * read-only mode.
774 */
775 fmem = lttng_fmemopen((void *) filter_expression,
776 strlen(filter_expression), "r");
777 if (!fmem) {
778 fprintf(stderr, "Error opening memory as stream\n");
779 ret = -LTTNG_ERR_FILTER_NOMEM;
780 goto error;
781 }
782 ctx = filter_parser_ctx_alloc(fmem);
783 if (!ctx) {
784 fprintf(stderr, "Error allocating parser\n");
785 ret = -LTTNG_ERR_FILTER_NOMEM;
786 goto filter_alloc_error;
787 }
788 ret = filter_parser_ctx_append_ast(ctx);
789 if (ret) {
790 fprintf(stderr, "Parse error\n");
791 ret = -LTTNG_ERR_FILTER_INVAL;
792 goto parse_error;
793 }
794 ret = filter_visitor_set_parent(ctx);
795 if (ret) {
796 fprintf(stderr, "Set parent error\n");
797 ret = -LTTNG_ERR_FILTER_INVAL;
798 goto parse_error;
799 }
800 if (print_xml) {
801 ret = filter_visitor_print_xml(ctx, stdout, 0);
802 if (ret) {
803 fflush(stdout);
804 fprintf(stderr, "XML print error\n");
805 ret = -LTTNG_ERR_FILTER_INVAL;
806 goto parse_error;
807 }
808 }
809
810 dbg_printf("Generating IR... ");
811 fflush(stdout);
812 ret = filter_visitor_ir_generate(ctx);
813 if (ret) {
814 fprintf(stderr, "Generate IR error\n");
815 ret = -LTTNG_ERR_FILTER_INVAL;
816 goto parse_error;
817 }
818 dbg_printf("done\n");
819
820 dbg_printf("Validating IR... ");
821 fflush(stdout);
822 ret = filter_visitor_ir_check_binary_op_nesting(ctx);
823 if (ret) {
824 ret = -LTTNG_ERR_FILTER_INVAL;
825 goto parse_error;
826 }
827 dbg_printf("done\n");
828
829 dbg_printf("Generating bytecode... ");
830 fflush(stdout);
831 ret = filter_visitor_bytecode_generate(ctx);
832 if (ret) {
833 fprintf(stderr, "Generate bytecode error\n");
834 ret = -LTTNG_ERR_FILTER_INVAL;
835 goto parse_error;
836 }
837 dbg_printf("done\n");
838 dbg_printf("Size of bytecode generated: %u bytes.\n",
839 bytecode_get_len(&ctx->bytecode->b));
840
841 lsm->u.enable.bytecode_len = sizeof(ctx->bytecode->b)
842 + bytecode_get_len(&ctx->bytecode->b);
843 lsm->u.enable.expression_len = strlen(filter_expression) + 1;
844
845 /* No need to keep the memory stream. */
846 if (fclose(fmem) != 0) {
847 perror("fclose");
848 }
849
850 *ctxp = ctx;
851 return 0;
852
853 parse_error:
854 filter_ir_free(ctx);
855 filter_parser_ctx_free(ctx);
856 filter_alloc_error:
857 if (fclose(fmem) != 0) {
858 perror("fclose");
859 }
860 error:
861 return ret;
862 }
863
864 /*
865 * Enable event(s) for a channel, possibly with exclusions and a filter.
866 * If no event name is specified, all events are enabled.
867 * If no channel name is specified, the default name is used.
868 * If filter expression is not NULL, the filter is set for the event.
869 * If exclusion count is not zero, the exclusions are set for the event.
870 * Returns size of returned session payload data or a negative error code.
871 */
872 int lttng_enable_event_with_exclusions(struct lttng_handle *handle,
873 struct lttng_event *ev, const char *channel_name,
874 const char *original_filter_expression,
875 int exclusion_count, char **exclusion_list)
876 {
877 struct lttcomm_session_msg lsm;
878 char *varlen_data;
879 int ret = 0;
880 unsigned int free_filter_expression = 0;
881 struct filter_parser_ctx *ctx = NULL;
882 /*
883 * Cast as non-const since we may replace the filter expression
884 * by a dynamically allocated string. Otherwise, the original
885 * string is not modified.
886 */
887 char *filter_expression = (char *) original_filter_expression;
888
889 if (handle == NULL || ev == NULL) {
890 ret = -LTTNG_ERR_INVALID;
891 goto error;
892 }
893
894 /* Empty filter string will always be rejected by the parser
895 * anyway, so treat this corner-case early to eliminate
896 * lttng_fmemopen error for 0-byte allocation.
897 */
898 if (filter_expression && filter_expression[0] == '\0') {
899 ret = -LTTNG_ERR_INVALID;
900 goto error;
901 }
902
903 memset(&lsm, 0, sizeof(lsm));
904
905 /* If no channel name, send empty string. */
906 if (channel_name == NULL) {
907 lttng_ctl_copy_string(lsm.u.enable.channel_name, "",
908 sizeof(lsm.u.enable.channel_name));
909 } else {
910 lttng_ctl_copy_string(lsm.u.enable.channel_name, channel_name,
911 sizeof(lsm.u.enable.channel_name));
912 }
913
914 if (ev->name[0] != '\0') {
915 lsm.cmd_type = LTTNG_ENABLE_EVENT;
916 } else {
917 lsm.cmd_type = LTTNG_ENABLE_ALL_EVENT;
918 }
919
920 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
921 memcpy(&lsm.u.enable.event, ev, sizeof(lsm.u.enable.event));
922
923 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
924 sizeof(lsm.session.name));
925 lsm.u.enable.exclusion_count = exclusion_count;
926 lsm.u.enable.bytecode_len = 0;
927
928 /*
929 * For the JUL domain, a filter is enforced except for the enable all
930 * event. This is done to avoid having the event in all sessions thus
931 * filtering by logger name.
932 */
933 if (exclusion_count == 0 && filter_expression == NULL &&
934 handle->domain.type != LTTNG_DOMAIN_JUL) {
935 goto ask_sessiond;
936 }
937
938 /*
939 * We have either a filter or some exclusions, so we need to set up
940 * a variable-length memory block from where to send the data
941 */
942
943 /* Parse filter expression */
944 if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL) {
945 if (handle->domain.type == LTTNG_DOMAIN_JUL) {
946 char *jul_filter;
947
948 /* Setup JUL filter if needed. */
949 jul_filter = set_jul_filter(filter_expression, ev);
950 if (!jul_filter) {
951 if (!filter_expression) {
952 /* No JUL and no filter, just skip everything below. */
953 goto ask_sessiond;
954 }
955 } else {
956 /*
957 * With a JUL filter, the original filter has been added to it
958 * thus replace the filter expression.
959 */
960 filter_expression = jul_filter;
961 free_filter_expression = 1;
962 }
963 }
964
965 ret = generate_filter(filter_expression, &lsm, &ctx);
966 if (ret) {
967 goto filter_error;
968 }
969 }
970
971 varlen_data = zmalloc(lsm.u.enable.bytecode_len
972 + lsm.u.enable.expression_len
973 + LTTNG_SYMBOL_NAME_LEN * exclusion_count);
974 if (!varlen_data) {
975 ret = -LTTNG_ERR_EXCLUSION_NOMEM;
976 goto mem_error;
977 }
978
979 /* Put exclusion names first in the data */
980 while (exclusion_count--) {
981 strncpy(varlen_data + LTTNG_SYMBOL_NAME_LEN * exclusion_count,
982 *(exclusion_list + exclusion_count), LTTNG_SYMBOL_NAME_LEN);
983 }
984 /* Add filter expression next */
985 if (lsm.u.enable.expression_len != 0) {
986 memcpy(varlen_data
987 + LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count,
988 filter_expression,
989 lsm.u.enable.expression_len);
990 }
991 /* Add filter bytecode next */
992 if (ctx && lsm.u.enable.bytecode_len != 0) {
993 memcpy(varlen_data
994 + LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count
995 + lsm.u.enable.expression_len,
996 &ctx->bytecode->b,
997 lsm.u.enable.bytecode_len);
998 }
999
1000 ret = lttng_ctl_ask_sessiond_varlen(&lsm, varlen_data,
1001 (LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count) +
1002 lsm.u.enable.bytecode_len + lsm.u.enable.expression_len, NULL);
1003 free(varlen_data);
1004
1005 mem_error:
1006 if (filter_expression && ctx) {
1007 filter_bytecode_free(ctx);
1008 filter_ir_free(ctx);
1009 filter_parser_ctx_free(ctx);
1010 }
1011 filter_error:
1012 if (free_filter_expression) {
1013 /*
1014 * The filter expression has been replaced and must be freed as it is
1015 * not the original filter expression received as a parameter.
1016 */
1017 free(filter_expression);
1018 }
1019 error:
1020 /*
1021 * Return directly to the caller and don't ask the sessiond since something
1022 * went wrong in the parsing of data above.
1023 */
1024 return ret;
1025
1026 ask_sessiond:
1027 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1028 return ret;
1029 }
1030
1031 /*
1032 * Disable event(s) of a channel and domain.
1033 * If no event name is specified, all events are disabled.
1034 * If no channel name is specified, the default 'channel0' is used.
1035 * Returns size of returned session payload data or a negative error code.
1036 */
1037 int lttng_disable_event(struct lttng_handle *handle, const char *name,
1038 const char *channel_name)
1039 {
1040 struct lttcomm_session_msg lsm;
1041
1042 if (handle == NULL) {
1043 return -LTTNG_ERR_INVALID;
1044 }
1045
1046 memset(&lsm, 0, sizeof(lsm));
1047
1048 /* If no channel name, send empty string. */
1049 if (channel_name == NULL) {
1050 lttng_ctl_copy_string(lsm.u.disable.channel_name, "",
1051 sizeof(lsm.u.disable.channel_name));
1052 } else {
1053 lttng_ctl_copy_string(lsm.u.disable.channel_name, channel_name,
1054 sizeof(lsm.u.disable.channel_name));
1055 }
1056
1057 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1058
1059 if (name != NULL) {
1060 lttng_ctl_copy_string(lsm.u.disable.name, name,
1061 sizeof(lsm.u.disable.name));
1062 lsm.cmd_type = LTTNG_DISABLE_EVENT;
1063 } else {
1064 lsm.cmd_type = LTTNG_DISABLE_ALL_EVENT;
1065 }
1066
1067 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1068 sizeof(lsm.session.name));
1069
1070 return lttng_ctl_ask_sessiond(&lsm, NULL);
1071 }
1072
1073 /*
1074 * Enable channel per domain
1075 * Returns size of returned session payload data or a negative error code.
1076 */
1077 int lttng_enable_channel(struct lttng_handle *handle,
1078 struct lttng_channel *chan)
1079 {
1080 struct lttcomm_session_msg lsm;
1081
1082 /*
1083 * NULL arguments are forbidden. No default values.
1084 */
1085 if (handle == NULL || chan == NULL) {
1086 return -LTTNG_ERR_INVALID;
1087 }
1088
1089 memset(&lsm, 0, sizeof(lsm));
1090
1091 memcpy(&lsm.u.channel.chan, chan, sizeof(lsm.u.channel.chan));
1092
1093 lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
1094
1095 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1096
1097 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1098 sizeof(lsm.session.name));
1099
1100 return lttng_ctl_ask_sessiond(&lsm, NULL);
1101 }
1102
1103 /*
1104 * All tracing will be stopped for registered events of the channel.
1105 * Returns size of returned session payload data or a negative error code.
1106 */
1107 int lttng_disable_channel(struct lttng_handle *handle, const char *name)
1108 {
1109 struct lttcomm_session_msg lsm;
1110
1111 /* Safety check. Both are mandatory */
1112 if (handle == NULL || name == NULL) {
1113 return -LTTNG_ERR_INVALID;
1114 }
1115
1116 memset(&lsm, 0, sizeof(lsm));
1117
1118 lsm.cmd_type = LTTNG_DISABLE_CHANNEL;
1119
1120 lttng_ctl_copy_string(lsm.u.disable.channel_name, name,
1121 sizeof(lsm.u.disable.channel_name));
1122
1123 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1124
1125 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1126 sizeof(lsm.session.name));
1127
1128 return lttng_ctl_ask_sessiond(&lsm, NULL);
1129 }
1130
1131 /*
1132 * Lists all available tracepoints of domain.
1133 * Sets the contents of the events array.
1134 * Returns the number of lttng_event entries in events;
1135 * on error, returns a negative value.
1136 */
1137 int lttng_list_tracepoints(struct lttng_handle *handle,
1138 struct lttng_event **events)
1139 {
1140 int ret;
1141 struct lttcomm_session_msg lsm;
1142
1143 if (handle == NULL) {
1144 return -LTTNG_ERR_INVALID;
1145 }
1146
1147 memset(&lsm, 0, sizeof(lsm));
1148 lsm.cmd_type = LTTNG_LIST_TRACEPOINTS;
1149 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1150
1151 ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
1152 if (ret < 0) {
1153 return ret;
1154 }
1155
1156 return ret / sizeof(struct lttng_event);
1157 }
1158
1159 /*
1160 * Lists all available tracepoint fields of domain.
1161 * Sets the contents of the event field array.
1162 * Returns the number of lttng_event_field entries in events;
1163 * on error, returns a negative value.
1164 */
1165 int lttng_list_tracepoint_fields(struct lttng_handle *handle,
1166 struct lttng_event_field **fields)
1167 {
1168 int ret;
1169 struct lttcomm_session_msg lsm;
1170
1171 if (handle == NULL) {
1172 return -LTTNG_ERR_INVALID;
1173 }
1174
1175 memset(&lsm, 0, sizeof(lsm));
1176 lsm.cmd_type = LTTNG_LIST_TRACEPOINT_FIELDS;
1177 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1178
1179 ret = lttng_ctl_ask_sessiond(&lsm, (void **) fields);
1180 if (ret < 0) {
1181 return ret;
1182 }
1183
1184 return ret / sizeof(struct lttng_event_field);
1185 }
1186
1187 /*
1188 * Returns a human readable string describing
1189 * the error code (a negative value).
1190 */
1191 const char *lttng_strerror(int code)
1192 {
1193 return error_get_str(code);
1194 }
1195
1196 /*
1197 * Create a brand new session using name and url for destination.
1198 *
1199 * Returns LTTNG_OK on success or a negative error code.
1200 */
1201 int lttng_create_session(const char *name, const char *url)
1202 {
1203 int ret;
1204 ssize_t size;
1205 struct lttcomm_session_msg lsm;
1206 struct lttng_uri *uris = NULL;
1207
1208 if (name == NULL) {
1209 return -LTTNG_ERR_INVALID;
1210 }
1211
1212 memset(&lsm, 0, sizeof(lsm));
1213
1214 lsm.cmd_type = LTTNG_CREATE_SESSION;
1215 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1216
1217 /* There should never be a data URL */
1218 size = uri_parse_str_urls(url, NULL, &uris);
1219 if (size < 0) {
1220 return -LTTNG_ERR_INVALID;
1221 }
1222
1223 lsm.u.uri.size = size;
1224
1225 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1226 sizeof(struct lttng_uri) * size, NULL);
1227
1228 free(uris);
1229 return ret;
1230 }
1231
1232 /*
1233 * Destroy session using name.
1234 * Returns size of returned session payload data or a negative error code.
1235 */
1236 int lttng_destroy_session(const char *session_name)
1237 {
1238 struct lttcomm_session_msg lsm;
1239
1240 if (session_name == NULL) {
1241 return -LTTNG_ERR_INVALID;
1242 }
1243
1244 memset(&lsm, 0, sizeof(lsm));
1245 lsm.cmd_type = LTTNG_DESTROY_SESSION;
1246
1247 lttng_ctl_copy_string(lsm.session.name, session_name,
1248 sizeof(lsm.session.name));
1249
1250 return lttng_ctl_ask_sessiond(&lsm, NULL);
1251 }
1252
1253 /*
1254 * Ask the session daemon for all available sessions.
1255 * Sets the contents of the sessions array.
1256 * Returns the number of lttng_session entries in sessions;
1257 * on error, returns a negative value.
1258 */
1259 int lttng_list_sessions(struct lttng_session **sessions)
1260 {
1261 int ret;
1262 struct lttcomm_session_msg lsm;
1263
1264 memset(&lsm, 0, sizeof(lsm));
1265 lsm.cmd_type = LTTNG_LIST_SESSIONS;
1266 ret = lttng_ctl_ask_sessiond(&lsm, (void**) sessions);
1267 if (ret < 0) {
1268 return ret;
1269 }
1270
1271 return ret / sizeof(struct lttng_session);
1272 }
1273
1274 /*
1275 * Ask the session daemon for all available domains of a session.
1276 * Sets the contents of the domains array.
1277 * Returns the number of lttng_domain entries in domains;
1278 * on error, returns a negative value.
1279 */
1280 int lttng_list_domains(const char *session_name,
1281 struct lttng_domain **domains)
1282 {
1283 int ret;
1284 struct lttcomm_session_msg lsm;
1285
1286 if (session_name == NULL) {
1287 return -LTTNG_ERR_INVALID;
1288 }
1289
1290 memset(&lsm, 0, sizeof(lsm));
1291 lsm.cmd_type = LTTNG_LIST_DOMAINS;
1292
1293 lttng_ctl_copy_string(lsm.session.name, session_name,
1294 sizeof(lsm.session.name));
1295
1296 ret = lttng_ctl_ask_sessiond(&lsm, (void**) domains);
1297 if (ret < 0) {
1298 return ret;
1299 }
1300
1301 return ret / sizeof(struct lttng_domain);
1302 }
1303
1304 /*
1305 * Ask the session daemon for all available channels of a session.
1306 * Sets the contents of the channels array.
1307 * Returns the number of lttng_channel entries in channels;
1308 * on error, returns a negative value.
1309 */
1310 int lttng_list_channels(struct lttng_handle *handle,
1311 struct lttng_channel **channels)
1312 {
1313 int ret;
1314 struct lttcomm_session_msg lsm;
1315
1316 if (handle == NULL) {
1317 return -LTTNG_ERR_INVALID;
1318 }
1319
1320 memset(&lsm, 0, sizeof(lsm));
1321 lsm.cmd_type = LTTNG_LIST_CHANNELS;
1322 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1323 sizeof(lsm.session.name));
1324
1325 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1326
1327 ret = lttng_ctl_ask_sessiond(&lsm, (void**) channels);
1328 if (ret < 0) {
1329 return ret;
1330 }
1331
1332 return ret / sizeof(struct lttng_channel);
1333 }
1334
1335 /*
1336 * Ask the session daemon for all available events of a session channel.
1337 * Sets the contents of the events array.
1338 * Returns the number of lttng_event entries in events;
1339 * on error, returns a negative value.
1340 */
1341 int lttng_list_events(struct lttng_handle *handle,
1342 const char *channel_name, struct lttng_event **events)
1343 {
1344 int ret;
1345 struct lttcomm_session_msg lsm;
1346
1347 /* Safety check. An handle and channel name are mandatory */
1348 if (handle == NULL || channel_name == NULL) {
1349 return -LTTNG_ERR_INVALID;
1350 }
1351
1352 memset(&lsm, 0, sizeof(lsm));
1353 lsm.cmd_type = LTTNG_LIST_EVENTS;
1354 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1355 sizeof(lsm.session.name));
1356 lttng_ctl_copy_string(lsm.u.list.channel_name, channel_name,
1357 sizeof(lsm.u.list.channel_name));
1358
1359 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1360
1361 ret = lttng_ctl_ask_sessiond(&lsm, (void**) events);
1362 if (ret < 0) {
1363 return ret;
1364 }
1365
1366 return ret / sizeof(struct lttng_event);
1367 }
1368
1369 /*
1370 * Sets the tracing_group variable with name.
1371 * This function allocates memory pointed to by tracing_group.
1372 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1373 */
1374 int lttng_set_tracing_group(const char *name)
1375 {
1376 if (name == NULL) {
1377 return -LTTNG_ERR_INVALID;
1378 }
1379
1380 if (asprintf(&tracing_group, "%s", name) < 0) {
1381 return -LTTNG_ERR_FATAL;
1382 }
1383
1384 return 0;
1385 }
1386
1387 /*
1388 * Returns size of returned session payload data or a negative error code.
1389 */
1390 int lttng_calibrate(struct lttng_handle *handle,
1391 struct lttng_calibrate *calibrate)
1392 {
1393 struct lttcomm_session_msg lsm;
1394
1395 /* Safety check. NULL pointer are forbidden */
1396 if (handle == NULL || calibrate == NULL) {
1397 return -LTTNG_ERR_INVALID;
1398 }
1399
1400 memset(&lsm, 0, sizeof(lsm));
1401 lsm.cmd_type = LTTNG_CALIBRATE;
1402 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1403
1404 memcpy(&lsm.u.calibrate, calibrate, sizeof(lsm.u.calibrate));
1405
1406 return lttng_ctl_ask_sessiond(&lsm, NULL);
1407 }
1408
1409 /*
1410 * Set default channel attributes.
1411 * If either or both of the arguments are null, attr content is zeroe'd.
1412 */
1413 void lttng_channel_set_default_attr(struct lttng_domain *domain,
1414 struct lttng_channel_attr *attr)
1415 {
1416 /* Safety check */
1417 if (attr == NULL || domain == NULL) {
1418 return;
1419 }
1420
1421 memset(attr, 0, sizeof(struct lttng_channel_attr));
1422
1423 /* Same for all domains. */
1424 attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
1425 attr->tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
1426 attr->tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT;
1427
1428 switch (domain->type) {
1429 case LTTNG_DOMAIN_KERNEL:
1430 attr->switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
1431 attr->read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
1432 attr->subbuf_size = default_get_kernel_channel_subbuf_size();
1433 attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
1434 attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
1435 break;
1436 case LTTNG_DOMAIN_UST:
1437 switch (domain->buf_type) {
1438 case LTTNG_BUFFER_PER_UID:
1439 attr->subbuf_size = default_get_ust_uid_channel_subbuf_size();
1440 attr->num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM;
1441 attr->output = DEFAULT_UST_UID_CHANNEL_OUTPUT;
1442 attr->switch_timer_interval = DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER;
1443 attr->read_timer_interval = DEFAULT_UST_UID_CHANNEL_READ_TIMER;
1444 break;
1445 case LTTNG_BUFFER_PER_PID:
1446 default:
1447 attr->subbuf_size = default_get_ust_pid_channel_subbuf_size();
1448 attr->num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM;
1449 attr->output = DEFAULT_UST_PID_CHANNEL_OUTPUT;
1450 attr->switch_timer_interval = DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER;
1451 attr->read_timer_interval = DEFAULT_UST_PID_CHANNEL_READ_TIMER;
1452 break;
1453 }
1454 default:
1455 /* Default behavior: leave set to 0. */
1456 break;
1457 }
1458 }
1459
1460 /*
1461 * Check if session daemon is alive.
1462 *
1463 * Return 1 if alive or 0 if not.
1464 * On error returns a negative value.
1465 */
1466 int lttng_session_daemon_alive(void)
1467 {
1468 int ret;
1469
1470 ret = set_session_daemon_path();
1471 if (ret < 0) {
1472 /* Error */
1473 return ret;
1474 }
1475
1476 if (*sessiond_sock_path == '\0') {
1477 /*
1478 * No socket path set. Weird error which means the constructor was not
1479 * called.
1480 */
1481 assert(0);
1482 }
1483
1484 ret = try_connect_sessiond(sessiond_sock_path);
1485 if (ret < 0) {
1486 /* Not alive */
1487 return 0;
1488 }
1489
1490 /* Is alive */
1491 return 1;
1492 }
1493
1494 /*
1495 * Set URL for a consumer for a session and domain.
1496 *
1497 * Return 0 on success, else a negative value.
1498 */
1499 int lttng_set_consumer_url(struct lttng_handle *handle,
1500 const char *control_url, const char *data_url)
1501 {
1502 int ret;
1503 ssize_t size;
1504 struct lttcomm_session_msg lsm;
1505 struct lttng_uri *uris = NULL;
1506
1507 if (handle == NULL || (control_url == NULL && data_url == NULL)) {
1508 return -LTTNG_ERR_INVALID;
1509 }
1510
1511 memset(&lsm, 0, sizeof(lsm));
1512
1513 lsm.cmd_type = LTTNG_SET_CONSUMER_URI;
1514
1515 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1516 sizeof(lsm.session.name));
1517 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1518
1519 size = uri_parse_str_urls(control_url, data_url, &uris);
1520 if (size < 0) {
1521 return -LTTNG_ERR_INVALID;
1522 }
1523
1524 lsm.u.uri.size = size;
1525
1526 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1527 sizeof(struct lttng_uri) * size, NULL);
1528
1529 free(uris);
1530 return ret;
1531 }
1532
1533 /*
1534 * [OBSOLETE]
1535 */
1536 int lttng_enable_consumer(struct lttng_handle *handle)
1537 {
1538 return -ENOSYS;
1539 }
1540
1541 /*
1542 * [OBSOLETE]
1543 */
1544 int lttng_disable_consumer(struct lttng_handle *handle)
1545 {
1546 return -ENOSYS;
1547 }
1548
1549 /*
1550 * This is an extension of create session that is ONLY and SHOULD only be used
1551 * by the lttng command line program. It exists to avoid using URI parsing in
1552 * the lttng client.
1553 *
1554 * We need the date and time for the trace path subdirectory for the case where
1555 * the user does NOT define one using either -o or -U. Using the normal
1556 * lttng_create_session API call, we have no clue on the session daemon side if
1557 * the URL was generated automatically by the client or define by the user.
1558 *
1559 * So this function "wrapper" is hidden from the public API, takes the datetime
1560 * string and appends it if necessary to the URI subdirectory before sending it
1561 * to the session daemon.
1562 *
1563 * With this extra function, the lttng_create_session call behavior is not
1564 * changed and the timestamp is appended to the URI on the session daemon side
1565 * if necessary.
1566 */
1567 int _lttng_create_session_ext(const char *name, const char *url,
1568 const char *datetime)
1569 {
1570 int ret;
1571 ssize_t size;
1572 struct lttcomm_session_msg lsm;
1573 struct lttng_uri *uris = NULL;
1574
1575 if (name == NULL || datetime == NULL) {
1576 return -LTTNG_ERR_INVALID;
1577 }
1578
1579 memset(&lsm, 0, sizeof(lsm));
1580
1581 lsm.cmd_type = LTTNG_CREATE_SESSION;
1582 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1583
1584 /* There should never be a data URL */
1585 size = uri_parse_str_urls(url, NULL, &uris);
1586 if (size < 0) {
1587 ret = -LTTNG_ERR_INVALID;
1588 goto error;
1589 }
1590
1591 lsm.u.uri.size = size;
1592
1593 if (size > 0 && uris[0].dtype != LTTNG_DST_PATH && strlen(uris[0].subdir) == 0) {
1594 /* Don't append datetime if the name was automatically created. */
1595 if (strncmp(name, DEFAULT_SESSION_NAME "-",
1596 strlen(DEFAULT_SESSION_NAME) + 1)) {
1597 ret = snprintf(uris[0].subdir, sizeof(uris[0].subdir), "%s-%s",
1598 name, datetime);
1599 } else {
1600 ret = snprintf(uris[0].subdir, sizeof(uris[0].subdir), "%s", name);
1601 }
1602 if (ret < 0) {
1603 PERROR("snprintf uri subdir");
1604 ret = -LTTNG_ERR_FATAL;
1605 goto error;
1606 }
1607 }
1608
1609 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1610 sizeof(struct lttng_uri) * size, NULL);
1611
1612 error:
1613 free(uris);
1614 return ret;
1615 }
1616
1617 /*
1618 * For a given session name, this call checks if the data is ready to be read
1619 * or is still being extracted by the consumer(s) hence not ready to be used by
1620 * any readers.
1621 */
1622 int lttng_data_pending(const char *session_name)
1623 {
1624 int ret;
1625 struct lttcomm_session_msg lsm;
1626
1627 if (session_name == NULL) {
1628 return -LTTNG_ERR_INVALID;
1629 }
1630
1631 memset(&lsm, 0, sizeof(lsm));
1632 lsm.cmd_type = LTTNG_DATA_PENDING;
1633
1634 lttng_ctl_copy_string(lsm.session.name, session_name,
1635 sizeof(lsm.session.name));
1636
1637 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1638
1639 /*
1640 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1641 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1642 * that the data is available. Yes it is hackish but for now this is the
1643 * only way.
1644 */
1645 if (ret == -1) {
1646 ret = 1;
1647 }
1648
1649 return ret;
1650 }
1651
1652 /*
1653 * Create a session exclusively used for snapshot.
1654 *
1655 * Returns LTTNG_OK on success or a negative error code.
1656 */
1657 int lttng_create_session_snapshot(const char *name, const char *snapshot_url)
1658 {
1659 int ret;
1660 ssize_t size;
1661 struct lttcomm_session_msg lsm;
1662 struct lttng_uri *uris = NULL;
1663
1664 if (name == NULL) {
1665 return -LTTNG_ERR_INVALID;
1666 }
1667
1668 memset(&lsm, 0, sizeof(lsm));
1669
1670 lsm.cmd_type = LTTNG_CREATE_SESSION_SNAPSHOT;
1671 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1672
1673 size = uri_parse_str_urls(snapshot_url, NULL, &uris);
1674 if (size < 0) {
1675 return -LTTNG_ERR_INVALID;
1676 }
1677
1678 lsm.u.uri.size = size;
1679
1680 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1681 sizeof(struct lttng_uri) * size, NULL);
1682
1683 free(uris);
1684 return ret;
1685 }
1686
1687 /*
1688 * Create a session exclusively used for live.
1689 *
1690 * Returns LTTNG_OK on success or a negative error code.
1691 */
1692 int lttng_create_session_live(const char *name, const char *url,
1693 unsigned int timer_interval)
1694 {
1695 int ret;
1696 ssize_t size;
1697 struct lttcomm_session_msg lsm;
1698 struct lttng_uri *uris = NULL;
1699
1700 if (name == NULL) {
1701 return -LTTNG_ERR_INVALID;
1702 }
1703
1704 memset(&lsm, 0, sizeof(lsm));
1705
1706 lsm.cmd_type = LTTNG_CREATE_SESSION_LIVE;
1707 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1708
1709 if (url) {
1710 size = uri_parse_str_urls(url, NULL, &uris);
1711 if (size <= 0) {
1712 ret = -LTTNG_ERR_INVALID;
1713 goto end;
1714 }
1715
1716 /* file:// is not accepted for live session. */
1717 if (uris[0].dtype == LTTNG_DST_PATH) {
1718 ret = -LTTNG_ERR_INVALID;
1719 goto end;
1720 }
1721 } else {
1722 size = 0;
1723 }
1724
1725 lsm.u.session_live.nb_uri = size;
1726 lsm.u.session_live.timer_interval = timer_interval;
1727
1728 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1729 sizeof(struct lttng_uri) * size, NULL);
1730
1731 end:
1732 free(uris);
1733 return ret;
1734 }
1735
1736 /*
1737 * lib constructor
1738 */
1739 static void __attribute__((constructor)) init()
1740 {
1741 /* Set default session group */
1742 lttng_set_tracing_group(DEFAULT_TRACING_GROUP);
1743 }
1744
1745 /*
1746 * lib destructor
1747 */
1748 static void __attribute__((destructor)) lttng_ctl_exit()
1749 {
1750 free(tracing_group);
1751 }
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