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Implement PID tracking for kernel tracing
[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 #define _LGPL_SOURCE
24 #include <assert.h>
25 #include <grp.h>
26 #include <errno.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <unistd.h>
31
32 #include <common/common.h>
33 #include <common/defaults.h>
34 #include <common/sessiond-comm/sessiond-comm.h>
35 #include <common/uri.h>
36 #include <common/utils.h>
37 #include <lttng/lttng.h>
38 #include <lttng/health-internal.h>
39
40 #include "filter/filter-ast.h"
41 #include "filter/filter-parser.h"
42 #include "filter/filter-bytecode.h"
43 #include "filter/memstream.h"
44 #include "lttng-ctl-helper.h"
45
46 #ifdef DEBUG
47 static const int print_xml = 1;
48 #define dbg_printf(fmt, args...) \
49 printf("[debug liblttng-ctl] " fmt, ## args)
50 #else
51 static const int print_xml = 0;
52 #define dbg_printf(fmt, args...) \
53 do { \
54 /* do nothing but check printf format */ \
55 if (0) \
56 printf("[debug liblttnctl] " fmt, ## args); \
57 } while (0)
58 #endif
59
60
61 /* Socket to session daemon for communication */
62 static int sessiond_socket;
63 static char sessiond_sock_path[PATH_MAX];
64
65 /* Variables */
66 static char *tracing_group;
67 static int connected;
68
69 /* Global */
70
71 /*
72 * Those two variables are used by error.h to silent or control the verbosity of
73 * error message. They are global to the library so application linking with it
74 * are able to compile correctly and also control verbosity of the library.
75 */
76 int lttng_opt_quiet;
77 int lttng_opt_verbose;
78 int lttng_opt_mi;
79
80 /*
81 * Copy string from src to dst and enforce null terminated byte.
82 */
83 LTTNG_HIDDEN
84 void lttng_ctl_copy_string(char *dst, const char *src, size_t len)
85 {
86 if (src && dst) {
87 strncpy(dst, src, len);
88 /* Enforce the NULL terminated byte */
89 dst[len - 1] = '\0';
90 } else if (dst) {
91 dst[0] = '\0';
92 }
93 }
94
95 /*
96 * Copy domain to lttcomm_session_msg domain.
97 *
98 * If domain is unknown, default domain will be the kernel.
99 */
100 LTTNG_HIDDEN
101 void lttng_ctl_copy_lttng_domain(struct lttng_domain *dst,
102 struct lttng_domain *src)
103 {
104 if (src && dst) {
105 switch (src->type) {
106 case LTTNG_DOMAIN_KERNEL:
107 case LTTNG_DOMAIN_UST:
108 case LTTNG_DOMAIN_JUL:
109 case LTTNG_DOMAIN_LOG4J:
110 case LTTNG_DOMAIN_PYTHON:
111 memcpy(dst, src, sizeof(struct lttng_domain));
112 break;
113 default:
114 memset(dst, 0, sizeof(struct lttng_domain));
115 break;
116 }
117 }
118 }
119
120 /*
121 * Send lttcomm_session_msg to the session daemon.
122 *
123 * On success, returns the number of bytes sent (>=0)
124 * On error, returns -1
125 */
126 static int send_session_msg(struct lttcomm_session_msg *lsm)
127 {
128 int ret;
129
130 if (!connected) {
131 ret = -LTTNG_ERR_NO_SESSIOND;
132 goto end;
133 }
134
135 DBG("LSM cmd type : %d", lsm->cmd_type);
136
137 ret = lttcomm_send_creds_unix_sock(sessiond_socket, lsm,
138 sizeof(struct lttcomm_session_msg));
139 if (ret < 0) {
140 ret = -LTTNG_ERR_FATAL;
141 }
142
143 end:
144 return ret;
145 }
146
147 /*
148 * Send var len data to the session daemon.
149 *
150 * On success, returns the number of bytes sent (>=0)
151 * On error, returns -1
152 */
153 static int send_session_varlen(void *data, size_t len)
154 {
155 int ret;
156
157 if (!connected) {
158 ret = -LTTNG_ERR_NO_SESSIOND;
159 goto end;
160 }
161
162 if (!data || !len) {
163 ret = 0;
164 goto end;
165 }
166
167 ret = lttcomm_send_unix_sock(sessiond_socket, data, len);
168 if (ret < 0) {
169 ret = -LTTNG_ERR_FATAL;
170 }
171
172 end:
173 return ret;
174 }
175
176 /*
177 * Receive data from the sessiond socket.
178 *
179 * On success, returns the number of bytes received (>=0)
180 * On error, returns -1 (recvmsg() error) or -ENOTCONN
181 */
182 static int recv_data_sessiond(void *buf, size_t len)
183 {
184 int ret;
185
186 if (!connected) {
187 ret = -LTTNG_ERR_NO_SESSIOND;
188 goto end;
189 }
190
191 ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len);
192 if (ret < 0) {
193 ret = -LTTNG_ERR_FATAL;
194 }
195
196 end:
197 return ret;
198 }
199
200 /*
201 * Check if we are in the specified group.
202 *
203 * If yes return 1, else return -1.
204 */
205 LTTNG_HIDDEN
206 int lttng_check_tracing_group(void)
207 {
208 struct group *grp_tracing; /* no free(). See getgrnam(3) */
209 gid_t *grp_list;
210 int grp_list_size, grp_id, i;
211 int ret = -1;
212 const char *grp_name = tracing_group;
213
214 /* Get GID of group 'tracing' */
215 grp_tracing = getgrnam(grp_name);
216 if (!grp_tracing) {
217 /* If grp_tracing is NULL, the group does not exist. */
218 goto end;
219 }
220
221 /* Get number of supplementary group IDs */
222 grp_list_size = getgroups(0, NULL);
223 if (grp_list_size < 0) {
224 PERROR("getgroups");
225 goto end;
226 }
227
228 /* Alloc group list of the right size */
229 grp_list = zmalloc(grp_list_size * sizeof(gid_t));
230 if (!grp_list) {
231 PERROR("malloc");
232 goto end;
233 }
234 grp_id = getgroups(grp_list_size, grp_list);
235 if (grp_id < 0) {
236 PERROR("getgroups");
237 goto free_list;
238 }
239
240 for (i = 0; i < grp_list_size; i++) {
241 if (grp_list[i] == grp_tracing->gr_gid) {
242 ret = 1;
243 break;
244 }
245 }
246
247 free_list:
248 free(grp_list);
249
250 end:
251 return ret;
252 }
253
254 /*
255 * Try connect to session daemon with sock_path.
256 *
257 * Return 0 on success, else -1
258 */
259 static int try_connect_sessiond(const char *sock_path)
260 {
261 int ret;
262
263 /* If socket exist, we check if the daemon listens for connect. */
264 ret = access(sock_path, F_OK);
265 if (ret < 0) {
266 /* Not alive */
267 goto error;
268 }
269
270 ret = lttcomm_connect_unix_sock(sock_path);
271 if (ret < 0) {
272 /* Not alive */
273 goto error;
274 }
275
276 ret = lttcomm_close_unix_sock(ret);
277 if (ret < 0) {
278 PERROR("lttcomm_close_unix_sock");
279 }
280
281 return 0;
282
283 error:
284 return -1;
285 }
286
287 /*
288 * Set sessiond socket path by putting it in the global sessiond_sock_path
289 * variable.
290 *
291 * Returns 0 on success, negative value on failure (the sessiond socket path
292 * is somehow too long or ENOMEM).
293 */
294 static int set_session_daemon_path(void)
295 {
296 int in_tgroup = 0; /* In tracing group */
297 uid_t uid;
298
299 uid = getuid();
300
301 if (uid != 0) {
302 /* Are we in the tracing group ? */
303 in_tgroup = lttng_check_tracing_group();
304 }
305
306 if ((uid == 0) || in_tgroup) {
307 lttng_ctl_copy_string(sessiond_sock_path,
308 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, sizeof(sessiond_sock_path));
309 }
310
311 if (uid != 0) {
312 int ret;
313
314 if (in_tgroup) {
315 /* Tracing group */
316 ret = try_connect_sessiond(sessiond_sock_path);
317 if (ret >= 0) {
318 goto end;
319 }
320 /* Global session daemon not available... */
321 }
322 /* ...or not in tracing group (and not root), default */
323
324 /*
325 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
326 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
327 */
328 ret = snprintf(sessiond_sock_path, sizeof(sessiond_sock_path),
329 DEFAULT_HOME_CLIENT_UNIX_SOCK, utils_get_home_dir());
330 if ((ret < 0) || (ret >= sizeof(sessiond_sock_path))) {
331 goto error;
332 }
333 }
334 end:
335 return 0;
336
337 error:
338 return -1;
339 }
340
341 /*
342 * Connect to the LTTng session daemon.
343 *
344 * On success, return 0. On error, return -1.
345 */
346 static int connect_sessiond(void)
347 {
348 int ret;
349
350 /* Don't try to connect if already connected. */
351 if (connected) {
352 return 0;
353 }
354
355 ret = set_session_daemon_path();
356 if (ret < 0) {
357 goto error;
358 }
359
360 /* Connect to the sesssion daemon */
361 ret = lttcomm_connect_unix_sock(sessiond_sock_path);
362 if (ret < 0) {
363 goto error;
364 }
365
366 sessiond_socket = ret;
367 connected = 1;
368
369 return 0;
370
371 error:
372 return -1;
373 }
374
375 /*
376 * Clean disconnect from the session daemon.
377 * On success, return 0. On error, return -1.
378 */
379 static int disconnect_sessiond(void)
380 {
381 int ret = 0;
382
383 if (connected) {
384 ret = lttcomm_close_unix_sock(sessiond_socket);
385 sessiond_socket = 0;
386 connected = 0;
387 }
388
389 return ret;
390 }
391
392 /*
393 * Ask the session daemon a specific command and put the data into buf.
394 * Takes extra var. len. data as input to send to the session daemon.
395 *
396 * Return size of data (only payload, not header) or a negative error code.
397 */
398 LTTNG_HIDDEN
399 int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg *lsm,
400 void *vardata, size_t varlen, void **buf)
401 {
402 int ret;
403 size_t size;
404 void *data = NULL;
405 struct lttcomm_lttng_msg llm;
406
407 ret = connect_sessiond();
408 if (ret < 0) {
409 ret = -LTTNG_ERR_NO_SESSIOND;
410 goto end;
411 }
412
413 /* Send command to session daemon */
414 ret = send_session_msg(lsm);
415 if (ret < 0) {
416 /* Ret value is a valid lttng error code. */
417 goto end;
418 }
419 /* Send var len data */
420 ret = send_session_varlen(vardata, varlen);
421 if (ret < 0) {
422 /* Ret value is a valid lttng error code. */
423 goto end;
424 }
425
426 /* Get header from data transmission */
427 ret = recv_data_sessiond(&llm, sizeof(llm));
428 if (ret < 0) {
429 /* Ret value is a valid lttng error code. */
430 goto end;
431 }
432
433 /* Check error code if OK */
434 if (llm.ret_code != LTTNG_OK) {
435 ret = -llm.ret_code;
436 goto end;
437 }
438
439 size = llm.data_size;
440 if (size == 0) {
441 /* If client free with size 0 */
442 if (buf != NULL) {
443 *buf = NULL;
444 }
445 ret = 0;
446 goto end;
447 }
448
449 data = zmalloc(size);
450 if (!data) {
451 ret = -ENOMEM;
452 goto end;
453 }
454
455 /* Get payload data */
456 ret = recv_data_sessiond(data, size);
457 if (ret < 0) {
458 free(data);
459 goto end;
460 }
461
462 /*
463 * Extra protection not to dereference a NULL pointer. If buf is NULL at
464 * this point, an error is returned and data is freed.
465 */
466 if (buf == NULL) {
467 ret = -LTTNG_ERR_INVALID;
468 free(data);
469 goto end;
470 }
471
472 *buf = data;
473 ret = size;
474
475 end:
476 disconnect_sessiond();
477 return ret;
478 }
479
480 /*
481 * Create lttng handle and return pointer.
482 * The returned pointer will be NULL in case of malloc() error.
483 */
484 struct lttng_handle *lttng_create_handle(const char *session_name,
485 struct lttng_domain *domain)
486 {
487 struct lttng_handle *handle = NULL;
488
489 if (domain == NULL) {
490 goto end;
491 }
492
493 handle = zmalloc(sizeof(struct lttng_handle));
494 if (handle == NULL) {
495 PERROR("malloc handle");
496 goto end;
497 }
498
499 /* Copy session name */
500 lttng_ctl_copy_string(handle->session_name, session_name,
501 sizeof(handle->session_name));
502
503 /* Copy lttng domain */
504 lttng_ctl_copy_lttng_domain(&handle->domain, domain);
505
506 end:
507 return handle;
508 }
509
510 /*
511 * Destroy handle by free(3) the pointer.
512 */
513 void lttng_destroy_handle(struct lttng_handle *handle)
514 {
515 free(handle);
516 }
517
518 /*
519 * Register an outside consumer.
520 * Returns size of returned session payload data or a negative error code.
521 */
522 int lttng_register_consumer(struct lttng_handle *handle,
523 const char *socket_path)
524 {
525 struct lttcomm_session_msg lsm;
526
527 if (handle == NULL || socket_path == NULL) {
528 return -LTTNG_ERR_INVALID;
529 }
530
531 memset(&lsm, 0, sizeof(lsm));
532 lsm.cmd_type = LTTNG_REGISTER_CONSUMER;
533 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
534 sizeof(lsm.session.name));
535 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
536
537 lttng_ctl_copy_string(lsm.u.reg.path, socket_path, sizeof(lsm.u.reg.path));
538
539 return lttng_ctl_ask_sessiond(&lsm, NULL);
540 }
541
542 /*
543 * Start tracing for all traces of the session.
544 * Returns size of returned session payload data or a negative error code.
545 */
546 int lttng_start_tracing(const char *session_name)
547 {
548 struct lttcomm_session_msg lsm;
549
550 if (session_name == NULL) {
551 return -LTTNG_ERR_INVALID;
552 }
553
554 memset(&lsm, 0, sizeof(lsm));
555 lsm.cmd_type = LTTNG_START_TRACE;
556
557 lttng_ctl_copy_string(lsm.session.name, session_name,
558 sizeof(lsm.session.name));
559
560 return lttng_ctl_ask_sessiond(&lsm, NULL);
561 }
562
563 /*
564 * Stop tracing for all traces of the session.
565 */
566 static int _lttng_stop_tracing(const char *session_name, int wait)
567 {
568 int ret, data_ret;
569 struct lttcomm_session_msg lsm;
570
571 if (session_name == NULL) {
572 return -LTTNG_ERR_INVALID;
573 }
574
575 memset(&lsm, 0, sizeof(lsm));
576 lsm.cmd_type = LTTNG_STOP_TRACE;
577
578 lttng_ctl_copy_string(lsm.session.name, session_name,
579 sizeof(lsm.session.name));
580
581 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
582 if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
583 goto error;
584 }
585
586 if (!wait) {
587 goto end;
588 }
589
590 /* Check for data availability */
591 do {
592 data_ret = lttng_data_pending(session_name);
593 if (data_ret < 0) {
594 /* Return the data available call error. */
595 ret = data_ret;
596 goto error;
597 }
598
599 /*
600 * Data sleep time before retrying (in usec). Don't sleep if the call
601 * returned value indicates availability.
602 */
603 if (data_ret) {
604 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME);
605 }
606 } while (data_ret != 0);
607
608 end:
609 error:
610 return ret;
611 }
612
613 /*
614 * Stop tracing and wait for data availability.
615 */
616 int lttng_stop_tracing(const char *session_name)
617 {
618 return _lttng_stop_tracing(session_name, 1);
619 }
620
621 /*
622 * Stop tracing but _don't_ wait for data availability.
623 */
624 int lttng_stop_tracing_no_wait(const char *session_name)
625 {
626 return _lttng_stop_tracing(session_name, 0);
627 }
628
629 /*
630 * Add context to a channel.
631 *
632 * If the given channel is NULL, add the contexts to all channels.
633 * The event_name param is ignored.
634 *
635 * Returns the size of the returned payload data or a negative error code.
636 */
637 int lttng_add_context(struct lttng_handle *handle,
638 struct lttng_event_context *ctx, const char *event_name,
639 const char *channel_name)
640 {
641 struct lttcomm_session_msg lsm;
642
643 /* Safety check. Both are mandatory */
644 if (handle == NULL || ctx == NULL) {
645 return -LTTNG_ERR_INVALID;
646 }
647
648 memset(&lsm, 0, sizeof(lsm));
649
650 lsm.cmd_type = LTTNG_ADD_CONTEXT;
651
652 /* If no channel name, send empty string. */
653 if (channel_name == NULL) {
654 lttng_ctl_copy_string(lsm.u.context.channel_name, "",
655 sizeof(lsm.u.context.channel_name));
656 } else {
657 lttng_ctl_copy_string(lsm.u.context.channel_name, channel_name,
658 sizeof(lsm.u.context.channel_name));
659 }
660
661 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
662
663 memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context));
664
665 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
666 sizeof(lsm.session.name));
667
668 return lttng_ctl_ask_sessiond(&lsm, NULL);
669 }
670
671 /*
672 * Enable event(s) for a channel.
673 * If no event name is specified, all events are enabled.
674 * If no channel name is specified, the default 'channel0' is used.
675 * Returns size of returned session payload data or a negative error code.
676 */
677 int lttng_enable_event(struct lttng_handle *handle,
678 struct lttng_event *ev, const char *channel_name)
679 {
680 return lttng_enable_event_with_exclusions(handle, ev, channel_name,
681 NULL, 0, NULL);
682 }
683
684 /*
685 * Create or enable an event with a filter expression.
686 *
687 * Return negative error value on error.
688 * Return size of returned session payload data if OK.
689 */
690 int lttng_enable_event_with_filter(struct lttng_handle *handle,
691 struct lttng_event *event, const char *channel_name,
692 const char *filter_expression)
693 {
694 return lttng_enable_event_with_exclusions(handle, event, channel_name,
695 filter_expression, 0, NULL);
696 }
697
698 /*
699 * Depending on the event, return a newly allocated agent filter expression or
700 * NULL if not applicable.
701 *
702 * An event with NO loglevel and the name is * will return NULL.
703 */
704 static char *set_agent_filter(const char *filter, struct lttng_event *ev)
705 {
706 int err;
707 char *agent_filter = NULL;
708
709 assert(ev);
710
711 /* Don't add filter for the '*' event. */
712 if (ev->name[0] != '*') {
713 if (filter) {
714 err = asprintf(&agent_filter, "(%s) && (logger_name == \"%s\")", filter,
715 ev->name);
716 } else {
717 err = asprintf(&agent_filter, "logger_name == \"%s\"", ev->name);
718 }
719 if (err < 0) {
720 PERROR("asprintf");
721 goto error;
722 }
723 }
724
725 /* Add loglevel filtering if any for the JUL domain. */
726 if (ev->loglevel_type != LTTNG_EVENT_LOGLEVEL_ALL) {
727 char *op;
728
729 if (ev->loglevel_type == LTTNG_EVENT_LOGLEVEL_RANGE) {
730 op = ">=";
731 } else {
732 op = "==";
733 }
734
735 if (filter || agent_filter) {
736 char *new_filter;
737
738 err = asprintf(&new_filter, "(%s) && (int_loglevel %s %d)",
739 agent_filter ? agent_filter : filter, op,
740 ev->loglevel);
741 if (agent_filter) {
742 free(agent_filter);
743 }
744 agent_filter = new_filter;
745 } else {
746 err = asprintf(&agent_filter, "int_loglevel %s %d", op,
747 ev->loglevel);
748 }
749 if (err < 0) {
750 PERROR("asprintf");
751 goto error;
752 }
753 }
754
755 return agent_filter;
756 error:
757 free(agent_filter);
758 return NULL;
759 }
760
761 /*
762 * Generate the filter bytecode from a give filter expression string. Put the
763 * newly allocated parser context in ctxp and populate the lsm object with the
764 * expression len.
765 *
766 * Return 0 on success else a LTTNG_ERR_* code and ctxp is untouched.
767 */
768 static int generate_filter(char *filter_expression,
769 struct lttcomm_session_msg *lsm, struct filter_parser_ctx **ctxp)
770 {
771 int ret;
772 struct filter_parser_ctx *ctx = NULL;
773 FILE *fmem = NULL;
774
775 assert(filter_expression);
776 assert(lsm);
777 assert(ctxp);
778
779 /*
780 * Casting const to non-const, as the underlying function will use it in
781 * read-only mode.
782 */
783 fmem = lttng_fmemopen((void *) filter_expression,
784 strlen(filter_expression), "r");
785 if (!fmem) {
786 fprintf(stderr, "Error opening memory as stream\n");
787 ret = -LTTNG_ERR_FILTER_NOMEM;
788 goto error;
789 }
790 ctx = filter_parser_ctx_alloc(fmem);
791 if (!ctx) {
792 fprintf(stderr, "Error allocating parser\n");
793 ret = -LTTNG_ERR_FILTER_NOMEM;
794 goto filter_alloc_error;
795 }
796 ret = filter_parser_ctx_append_ast(ctx);
797 if (ret) {
798 fprintf(stderr, "Parse error\n");
799 ret = -LTTNG_ERR_FILTER_INVAL;
800 goto parse_error;
801 }
802 ret = filter_visitor_set_parent(ctx);
803 if (ret) {
804 fprintf(stderr, "Set parent error\n");
805 ret = -LTTNG_ERR_FILTER_INVAL;
806 goto parse_error;
807 }
808 if (print_xml) {
809 ret = filter_visitor_print_xml(ctx, stdout, 0);
810 if (ret) {
811 fflush(stdout);
812 fprintf(stderr, "XML print error\n");
813 ret = -LTTNG_ERR_FILTER_INVAL;
814 goto parse_error;
815 }
816 }
817
818 dbg_printf("Generating IR... ");
819 fflush(stdout);
820 ret = filter_visitor_ir_generate(ctx);
821 if (ret) {
822 fprintf(stderr, "Generate IR error\n");
823 ret = -LTTNG_ERR_FILTER_INVAL;
824 goto parse_error;
825 }
826 dbg_printf("done\n");
827
828 dbg_printf("Validating IR... ");
829 fflush(stdout);
830 ret = filter_visitor_ir_check_binary_op_nesting(ctx);
831 if (ret) {
832 ret = -LTTNG_ERR_FILTER_INVAL;
833 goto parse_error;
834 }
835 /* Validate strings used as literals in the expression */
836 ret = filter_visitor_ir_validate_string(ctx);
837 if (ret) {
838 ret = -LTTNG_ERR_FILTER_INVAL;
839 goto parse_error;
840 }
841 dbg_printf("done\n");
842
843 dbg_printf("Generating bytecode... ");
844 fflush(stdout);
845 ret = filter_visitor_bytecode_generate(ctx);
846 if (ret) {
847 fprintf(stderr, "Generate bytecode error\n");
848 ret = -LTTNG_ERR_FILTER_INVAL;
849 goto parse_error;
850 }
851 dbg_printf("done\n");
852 dbg_printf("Size of bytecode generated: %u bytes.\n",
853 bytecode_get_len(&ctx->bytecode->b));
854
855 lsm->u.enable.bytecode_len = sizeof(ctx->bytecode->b)
856 + bytecode_get_len(&ctx->bytecode->b);
857 lsm->u.enable.expression_len = strlen(filter_expression) + 1;
858
859 /* No need to keep the memory stream. */
860 if (fclose(fmem) != 0) {
861 PERROR("fclose");
862 }
863
864 *ctxp = ctx;
865 return 0;
866
867 parse_error:
868 filter_ir_free(ctx);
869 filter_parser_ctx_free(ctx);
870 filter_alloc_error:
871 if (fclose(fmem) != 0) {
872 PERROR("fclose");
873 }
874 error:
875 return ret;
876 }
877
878 /*
879 * Enable event(s) for a channel, possibly with exclusions and a filter.
880 * If no event name is specified, all events are enabled.
881 * If no channel name is specified, the default name is used.
882 * If filter expression is not NULL, the filter is set for the event.
883 * If exclusion count is not zero, the exclusions are set for the event.
884 * Returns size of returned session payload data or a negative error code.
885 */
886 int lttng_enable_event_with_exclusions(struct lttng_handle *handle,
887 struct lttng_event *ev, const char *channel_name,
888 const char *original_filter_expression,
889 int exclusion_count, char **exclusion_list)
890 {
891 struct lttcomm_session_msg lsm;
892 char *varlen_data;
893 int ret = 0;
894 unsigned int free_filter_expression = 0;
895 struct filter_parser_ctx *ctx = NULL;
896 /*
897 * Cast as non-const since we may replace the filter expression
898 * by a dynamically allocated string. Otherwise, the original
899 * string is not modified.
900 */
901 char *filter_expression = (char *) original_filter_expression;
902
903 if (handle == NULL || ev == NULL) {
904 ret = -LTTNG_ERR_INVALID;
905 goto error;
906 }
907
908 /* Empty filter string will always be rejected by the parser
909 * anyway, so treat this corner-case early to eliminate
910 * lttng_fmemopen error for 0-byte allocation.
911 */
912 if (filter_expression && filter_expression[0] == '\0') {
913 ret = -LTTNG_ERR_INVALID;
914 goto error;
915 }
916
917 memset(&lsm, 0, sizeof(lsm));
918
919 /* If no channel name, send empty string. */
920 if (channel_name == NULL) {
921 lttng_ctl_copy_string(lsm.u.enable.channel_name, "",
922 sizeof(lsm.u.enable.channel_name));
923 } else {
924 lttng_ctl_copy_string(lsm.u.enable.channel_name, channel_name,
925 sizeof(lsm.u.enable.channel_name));
926 }
927
928 lsm.cmd_type = LTTNG_ENABLE_EVENT;
929 if (ev->name[0] == '\0') {
930 /* Enable all events */
931 lttng_ctl_copy_string(ev->name, "*", sizeof(ev->name));
932 }
933
934 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
935 /* FIXME: copying non-packed struct to packed struct. */
936 memcpy(&lsm.u.enable.event, ev, sizeof(lsm.u.enable.event));
937
938 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
939 sizeof(lsm.session.name));
940 lsm.u.enable.exclusion_count = exclusion_count;
941 lsm.u.enable.bytecode_len = 0;
942
943 /*
944 * For the JUL domain, a filter is enforced except for the enable all
945 * event. This is done to avoid having the event in all sessions thus
946 * filtering by logger name.
947 */
948 if (exclusion_count == 0 && filter_expression == NULL &&
949 (handle->domain.type != LTTNG_DOMAIN_JUL &&
950 handle->domain.type != LTTNG_DOMAIN_LOG4J &&
951 handle->domain.type != LTTNG_DOMAIN_PYTHON)) {
952 goto ask_sessiond;
953 }
954
955 /*
956 * We have either a filter or some exclusions, so we need to set up
957 * a variable-length memory block from where to send the data
958 */
959
960 /* Parse filter expression */
961 if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
962 || handle->domain.type == LTTNG_DOMAIN_LOG4J
963 || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
964 if (handle->domain.type == LTTNG_DOMAIN_JUL ||
965 handle->domain.type == LTTNG_DOMAIN_LOG4J ||
966 handle->domain.type == LTTNG_DOMAIN_PYTHON) {
967 char *agent_filter;
968
969 /* Setup JUL filter if needed. */
970 agent_filter = set_agent_filter(filter_expression, ev);
971 if (!agent_filter) {
972 if (!filter_expression) {
973 /* No JUL and no filter, just skip everything below. */
974 goto ask_sessiond;
975 }
976 } else {
977 /*
978 * With an agent filter, the original filter has been added to
979 * it thus replace the filter expression.
980 */
981 filter_expression = agent_filter;
982 free_filter_expression = 1;
983 }
984 }
985
986 ret = generate_filter(filter_expression, &lsm, &ctx);
987 if (ret) {
988 goto filter_error;
989 }
990 }
991
992 varlen_data = zmalloc(lsm.u.enable.bytecode_len
993 + lsm.u.enable.expression_len
994 + LTTNG_SYMBOL_NAME_LEN * exclusion_count);
995 if (!varlen_data) {
996 ret = -LTTNG_ERR_EXCLUSION_NOMEM;
997 goto mem_error;
998 }
999
1000 /* Put exclusion names first in the data */
1001 while (exclusion_count--) {
1002 strncpy(varlen_data + LTTNG_SYMBOL_NAME_LEN * exclusion_count,
1003 *(exclusion_list + exclusion_count), LTTNG_SYMBOL_NAME_LEN);
1004 }
1005 /* Add filter expression next */
1006 if (lsm.u.enable.expression_len != 0) {
1007 memcpy(varlen_data
1008 + LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count,
1009 filter_expression,
1010 lsm.u.enable.expression_len);
1011 }
1012 /* Add filter bytecode next */
1013 if (ctx && lsm.u.enable.bytecode_len != 0) {
1014 memcpy(varlen_data
1015 + LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count
1016 + lsm.u.enable.expression_len,
1017 &ctx->bytecode->b,
1018 lsm.u.enable.bytecode_len);
1019 }
1020
1021 ret = lttng_ctl_ask_sessiond_varlen(&lsm, varlen_data,
1022 (LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count) +
1023 lsm.u.enable.bytecode_len + lsm.u.enable.expression_len, NULL);
1024 free(varlen_data);
1025
1026 mem_error:
1027 if (filter_expression && ctx) {
1028 filter_bytecode_free(ctx);
1029 filter_ir_free(ctx);
1030 filter_parser_ctx_free(ctx);
1031 }
1032 filter_error:
1033 if (free_filter_expression) {
1034 /*
1035 * The filter expression has been replaced and must be freed as it is
1036 * not the original filter expression received as a parameter.
1037 */
1038 free(filter_expression);
1039 }
1040 error:
1041 /*
1042 * Return directly to the caller and don't ask the sessiond since something
1043 * went wrong in the parsing of data above.
1044 */
1045 return ret;
1046
1047 ask_sessiond:
1048 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1049 return ret;
1050 }
1051
1052 int lttng_disable_event_ext(struct lttng_handle *handle,
1053 struct lttng_event *ev, const char *channel_name,
1054 const char *original_filter_expression)
1055 {
1056 struct lttcomm_session_msg lsm;
1057 char *varlen_data;
1058 int ret = 0;
1059 unsigned int free_filter_expression = 0;
1060 struct filter_parser_ctx *ctx = NULL;
1061 /*
1062 * Cast as non-const since we may replace the filter expression
1063 * by a dynamically allocated string. Otherwise, the original
1064 * string is not modified.
1065 */
1066 char *filter_expression = (char *) original_filter_expression;
1067
1068 if (handle == NULL || ev == NULL) {
1069 ret = -LTTNG_ERR_INVALID;
1070 goto error;
1071 }
1072
1073 /* Empty filter string will always be rejected by the parser
1074 * anyway, so treat this corner-case early to eliminate
1075 * lttng_fmemopen error for 0-byte allocation.
1076 */
1077 if (filter_expression && filter_expression[0] == '\0') {
1078 ret = -LTTNG_ERR_INVALID;
1079 goto error;
1080 }
1081
1082 memset(&lsm, 0, sizeof(lsm));
1083
1084 /* If no channel name, send empty string. */
1085 if (channel_name == NULL) {
1086 lttng_ctl_copy_string(lsm.u.disable.channel_name, "",
1087 sizeof(lsm.u.disable.channel_name));
1088 } else {
1089 lttng_ctl_copy_string(lsm.u.disable.channel_name, channel_name,
1090 sizeof(lsm.u.disable.channel_name));
1091 }
1092
1093 lsm.cmd_type = LTTNG_DISABLE_EVENT;
1094 if (ev->name[0] == '\0') {
1095 /* Disable all events */
1096 lttng_ctl_copy_string(ev->name, "*", sizeof(ev->name));
1097 }
1098
1099 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1100 /* FIXME: copying non-packed struct to packed struct. */
1101 memcpy(&lsm.u.disable.event, ev, sizeof(lsm.u.disable.event));
1102
1103 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1104 sizeof(lsm.session.name));
1105 lsm.u.disable.bytecode_len = 0;
1106
1107 /*
1108 * For the JUL domain, a filter is enforced except for the
1109 * disable all event. This is done to avoid having the event in
1110 * all sessions thus filtering by logger name.
1111 */
1112 if (filter_expression == NULL &&
1113 (handle->domain.type != LTTNG_DOMAIN_JUL &&
1114 handle->domain.type != LTTNG_DOMAIN_LOG4J &&
1115 handle->domain.type != LTTNG_DOMAIN_PYTHON)) {
1116 goto ask_sessiond;
1117 }
1118
1119 /*
1120 * We have a filter, so we need to set up a variable-length
1121 * memory block from where to send the data.
1122 */
1123
1124 /* Parse filter expression */
1125 if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL
1126 || handle->domain.type == LTTNG_DOMAIN_LOG4J
1127 || handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1128 if (handle->domain.type == LTTNG_DOMAIN_JUL ||
1129 handle->domain.type == LTTNG_DOMAIN_LOG4J ||
1130 handle->domain.type == LTTNG_DOMAIN_PYTHON) {
1131 char *agent_filter;
1132
1133 /* Setup JUL filter if needed. */
1134 agent_filter = set_agent_filter(filter_expression, ev);
1135 if (!agent_filter) {
1136 if (!filter_expression) {
1137 /* No JUL and no filter, just skip everything below. */
1138 goto ask_sessiond;
1139 }
1140 } else {
1141 /*
1142 * With a JUL filter, the original filter has been added to it
1143 * thus replace the filter expression.
1144 */
1145 filter_expression = agent_filter;
1146 free_filter_expression = 1;
1147 }
1148 }
1149
1150 ret = generate_filter(filter_expression, &lsm, &ctx);
1151 if (ret) {
1152 goto filter_error;
1153 }
1154 }
1155
1156 varlen_data = zmalloc(lsm.u.disable.bytecode_len
1157 + lsm.u.disable.expression_len);
1158 if (!varlen_data) {
1159 ret = -LTTNG_ERR_EXCLUSION_NOMEM;
1160 goto mem_error;
1161 }
1162
1163 /* Add filter expression */
1164 if (lsm.u.disable.expression_len != 0) {
1165 memcpy(varlen_data,
1166 filter_expression,
1167 lsm.u.disable.expression_len);
1168 }
1169 /* Add filter bytecode next */
1170 if (ctx && lsm.u.disable.bytecode_len != 0) {
1171 memcpy(varlen_data
1172 + lsm.u.disable.expression_len,
1173 &ctx->bytecode->b,
1174 lsm.u.disable.bytecode_len);
1175 }
1176
1177 ret = lttng_ctl_ask_sessiond_varlen(&lsm, varlen_data,
1178 lsm.u.disable.bytecode_len + lsm.u.disable.expression_len, NULL);
1179 free(varlen_data);
1180
1181 mem_error:
1182 if (filter_expression && ctx) {
1183 filter_bytecode_free(ctx);
1184 filter_ir_free(ctx);
1185 filter_parser_ctx_free(ctx);
1186 }
1187 filter_error:
1188 if (free_filter_expression) {
1189 /*
1190 * The filter expression has been replaced and must be freed as it is
1191 * not the original filter expression received as a parameter.
1192 */
1193 free(filter_expression);
1194 }
1195 error:
1196 /*
1197 * Return directly to the caller and don't ask the sessiond since something
1198 * went wrong in the parsing of data above.
1199 */
1200 return ret;
1201
1202 ask_sessiond:
1203 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1204 return ret;
1205 }
1206
1207 /*
1208 * Disable event(s) of a channel and domain.
1209 * If no event name is specified, all events are disabled.
1210 * If no channel name is specified, the default 'channel0' is used.
1211 * Returns size of returned session payload data or a negative error code.
1212 */
1213 int lttng_disable_event(struct lttng_handle *handle, const char *name,
1214 const char *channel_name)
1215 {
1216 struct lttng_event ev;
1217
1218 memset(&ev, 0, sizeof(ev));
1219 ev.loglevel = -1;
1220 ev.type = LTTNG_EVENT_ALL;
1221 lttng_ctl_copy_string(ev.name, name, sizeof(ev.name));
1222 return lttng_disable_event_ext(handle, &ev, channel_name, NULL);
1223 }
1224
1225 /*
1226 * Enable channel per domain
1227 * Returns size of returned session payload data or a negative error code.
1228 */
1229 int lttng_enable_channel(struct lttng_handle *handle,
1230 struct lttng_channel *chan)
1231 {
1232 struct lttcomm_session_msg lsm;
1233
1234 /*
1235 * NULL arguments are forbidden. No default values.
1236 */
1237 if (handle == NULL || chan == NULL) {
1238 return -LTTNG_ERR_INVALID;
1239 }
1240
1241 memset(&lsm, 0, sizeof(lsm));
1242
1243 memcpy(&lsm.u.channel.chan, chan, sizeof(lsm.u.channel.chan));
1244
1245 lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
1246
1247 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1248
1249 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1250 sizeof(lsm.session.name));
1251
1252 return lttng_ctl_ask_sessiond(&lsm, NULL);
1253 }
1254
1255 /*
1256 * All tracing will be stopped for registered events of the channel.
1257 * Returns size of returned session payload data or a negative error code.
1258 */
1259 int lttng_disable_channel(struct lttng_handle *handle, const char *name)
1260 {
1261 struct lttcomm_session_msg lsm;
1262
1263 /* Safety check. Both are mandatory */
1264 if (handle == NULL || name == NULL) {
1265 return -LTTNG_ERR_INVALID;
1266 }
1267
1268 memset(&lsm, 0, sizeof(lsm));
1269
1270 lsm.cmd_type = LTTNG_DISABLE_CHANNEL;
1271
1272 lttng_ctl_copy_string(lsm.u.disable.channel_name, name,
1273 sizeof(lsm.u.disable.channel_name));
1274
1275 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1276
1277 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1278 sizeof(lsm.session.name));
1279
1280 return lttng_ctl_ask_sessiond(&lsm, NULL);
1281 }
1282
1283 /*
1284 * Add PID to session tracker.
1285 * Return 0 on success else a negative LTTng error code.
1286 */
1287 int lttng_track_pid(struct lttng_handle *handle, int pid)
1288 {
1289 struct lttcomm_session_msg lsm;
1290
1291 /*
1292 * NULL arguments are forbidden. No default values.
1293 */
1294 if (handle == NULL) {
1295 return -LTTNG_ERR_INVALID;
1296 }
1297
1298 memset(&lsm, 0, sizeof(lsm));
1299
1300 lsm.cmd_type = LTTNG_TRACK_PID;
1301 lsm.u.pid_tracker.pid = pid;
1302
1303 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1304
1305 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1306 sizeof(lsm.session.name));
1307
1308 return lttng_ctl_ask_sessiond(&lsm, NULL);
1309 }
1310
1311 /*
1312 * Remove PID from session tracker.
1313 * Return 0 on success else a negative LTTng error code.
1314 */
1315 int lttng_untrack_pid(struct lttng_handle *handle, int pid)
1316 {
1317 struct lttcomm_session_msg lsm;
1318
1319 /*
1320 * NULL arguments are forbidden. No default values.
1321 */
1322 if (handle == NULL) {
1323 return -LTTNG_ERR_INVALID;
1324 }
1325
1326 memset(&lsm, 0, sizeof(lsm));
1327
1328 lsm.cmd_type = LTTNG_UNTRACK_PID;
1329 lsm.u.pid_tracker.pid = pid;
1330
1331 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1332
1333 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1334 sizeof(lsm.session.name));
1335
1336 return lttng_ctl_ask_sessiond(&lsm, NULL);
1337 }
1338
1339 /*
1340 * Lists all available tracepoints of domain.
1341 * Sets the contents of the events array.
1342 * Returns the number of lttng_event entries in events;
1343 * on error, returns a negative value.
1344 */
1345 int lttng_list_tracepoints(struct lttng_handle *handle,
1346 struct lttng_event **events)
1347 {
1348 int ret;
1349 struct lttcomm_session_msg lsm;
1350
1351 if (handle == NULL) {
1352 return -LTTNG_ERR_INVALID;
1353 }
1354
1355 memset(&lsm, 0, sizeof(lsm));
1356 lsm.cmd_type = LTTNG_LIST_TRACEPOINTS;
1357 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1358
1359 ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
1360 if (ret < 0) {
1361 return ret;
1362 }
1363
1364 return ret / sizeof(struct lttng_event);
1365 }
1366
1367 /*
1368 * Lists all available tracepoint fields of domain.
1369 * Sets the contents of the event field array.
1370 * Returns the number of lttng_event_field entries in events;
1371 * on error, returns a negative value.
1372 */
1373 int lttng_list_tracepoint_fields(struct lttng_handle *handle,
1374 struct lttng_event_field **fields)
1375 {
1376 int ret;
1377 struct lttcomm_session_msg lsm;
1378
1379 if (handle == NULL) {
1380 return -LTTNG_ERR_INVALID;
1381 }
1382
1383 memset(&lsm, 0, sizeof(lsm));
1384 lsm.cmd_type = LTTNG_LIST_TRACEPOINT_FIELDS;
1385 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1386
1387 ret = lttng_ctl_ask_sessiond(&lsm, (void **) fields);
1388 if (ret < 0) {
1389 return ret;
1390 }
1391
1392 return ret / sizeof(struct lttng_event_field);
1393 }
1394
1395 /*
1396 * Lists all available kernel system calls. Allocates and sets the contents of
1397 * the events array.
1398 *
1399 * Returns the number of lttng_event entries in events; on error, returns a
1400 * negative value.
1401 */
1402 int lttng_list_syscalls(struct lttng_event **events)
1403 {
1404 int ret;
1405 struct lttcomm_session_msg lsm;
1406
1407 if (!events) {
1408 return -LTTNG_ERR_INVALID;
1409 }
1410
1411 memset(&lsm, 0, sizeof(lsm));
1412 lsm.cmd_type = LTTNG_LIST_SYSCALLS;
1413 /* Force kernel domain for system calls. */
1414 lsm.domain.type = LTTNG_DOMAIN_KERNEL;
1415
1416 ret = lttng_ctl_ask_sessiond(&lsm, (void **) events);
1417 if (ret < 0) {
1418 return ret;
1419 }
1420
1421 return ret / sizeof(struct lttng_event);
1422 }
1423
1424 /*
1425 * Returns a human readable string describing
1426 * the error code (a negative value).
1427 */
1428 const char *lttng_strerror(int code)
1429 {
1430 return error_get_str(code);
1431 }
1432
1433 /*
1434 * Create a brand new session using name and url for destination.
1435 *
1436 * Returns LTTNG_OK on success or a negative error code.
1437 */
1438 int lttng_create_session(const char *name, const char *url)
1439 {
1440 int ret;
1441 ssize_t size;
1442 struct lttcomm_session_msg lsm;
1443 struct lttng_uri *uris = NULL;
1444
1445 if (name == NULL) {
1446 return -LTTNG_ERR_INVALID;
1447 }
1448
1449 memset(&lsm, 0, sizeof(lsm));
1450
1451 lsm.cmd_type = LTTNG_CREATE_SESSION;
1452 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1453
1454 /* There should never be a data URL */
1455 size = uri_parse_str_urls(url, NULL, &uris);
1456 if (size < 0) {
1457 return -LTTNG_ERR_INVALID;
1458 }
1459
1460 lsm.u.uri.size = size;
1461
1462 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1463 sizeof(struct lttng_uri) * size, NULL);
1464
1465 free(uris);
1466 return ret;
1467 }
1468
1469 /*
1470 * Destroy session using name.
1471 * Returns size of returned session payload data or a negative error code.
1472 */
1473 int lttng_destroy_session(const char *session_name)
1474 {
1475 struct lttcomm_session_msg lsm;
1476
1477 if (session_name == NULL) {
1478 return -LTTNG_ERR_INVALID;
1479 }
1480
1481 memset(&lsm, 0, sizeof(lsm));
1482 lsm.cmd_type = LTTNG_DESTROY_SESSION;
1483
1484 lttng_ctl_copy_string(lsm.session.name, session_name,
1485 sizeof(lsm.session.name));
1486
1487 return lttng_ctl_ask_sessiond(&lsm, NULL);
1488 }
1489
1490 /*
1491 * Ask the session daemon for all available sessions.
1492 * Sets the contents of the sessions array.
1493 * Returns the number of lttng_session entries in sessions;
1494 * on error, returns a negative value.
1495 */
1496 int lttng_list_sessions(struct lttng_session **sessions)
1497 {
1498 int ret;
1499 struct lttcomm_session_msg lsm;
1500
1501 memset(&lsm, 0, sizeof(lsm));
1502 lsm.cmd_type = LTTNG_LIST_SESSIONS;
1503 ret = lttng_ctl_ask_sessiond(&lsm, (void**) sessions);
1504 if (ret < 0) {
1505 return ret;
1506 }
1507
1508 return ret / sizeof(struct lttng_session);
1509 }
1510
1511 int lttng_set_session_shm_path(const char *session_name,
1512 const char *shm_path)
1513 {
1514 struct lttcomm_session_msg lsm;
1515
1516 if (session_name == NULL) {
1517 return -LTTNG_ERR_INVALID;
1518 }
1519
1520 memset(&lsm, 0, sizeof(lsm));
1521 lsm.cmd_type = LTTNG_SET_SESSION_SHM_PATH;
1522
1523 lttng_ctl_copy_string(lsm.session.name, session_name,
1524 sizeof(lsm.session.name));
1525 lttng_ctl_copy_string(lsm.u.set_shm_path.shm_path, shm_path,
1526 sizeof(lsm.u.set_shm_path.shm_path));
1527
1528 return lttng_ctl_ask_sessiond(&lsm, NULL);
1529 }
1530
1531 /*
1532 * Ask the session daemon for all available domains of a session.
1533 * Sets the contents of the domains array.
1534 * Returns the number of lttng_domain entries in domains;
1535 * on error, returns a negative value.
1536 */
1537 int lttng_list_domains(const char *session_name,
1538 struct lttng_domain **domains)
1539 {
1540 int ret;
1541 struct lttcomm_session_msg lsm;
1542
1543 if (session_name == NULL) {
1544 return -LTTNG_ERR_INVALID;
1545 }
1546
1547 memset(&lsm, 0, sizeof(lsm));
1548 lsm.cmd_type = LTTNG_LIST_DOMAINS;
1549
1550 lttng_ctl_copy_string(lsm.session.name, session_name,
1551 sizeof(lsm.session.name));
1552
1553 ret = lttng_ctl_ask_sessiond(&lsm, (void**) domains);
1554 if (ret < 0) {
1555 return ret;
1556 }
1557
1558 return ret / sizeof(struct lttng_domain);
1559 }
1560
1561 /*
1562 * Ask the session daemon for all available channels of a session.
1563 * Sets the contents of the channels array.
1564 * Returns the number of lttng_channel entries in channels;
1565 * on error, returns a negative value.
1566 */
1567 int lttng_list_channels(struct lttng_handle *handle,
1568 struct lttng_channel **channels)
1569 {
1570 int ret;
1571 struct lttcomm_session_msg lsm;
1572
1573 if (handle == NULL) {
1574 return -LTTNG_ERR_INVALID;
1575 }
1576
1577 memset(&lsm, 0, sizeof(lsm));
1578 lsm.cmd_type = LTTNG_LIST_CHANNELS;
1579 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1580 sizeof(lsm.session.name));
1581
1582 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1583
1584 ret = lttng_ctl_ask_sessiond(&lsm, (void**) channels);
1585 if (ret < 0) {
1586 return ret;
1587 }
1588
1589 return ret / sizeof(struct lttng_channel);
1590 }
1591
1592 /*
1593 * Ask the session daemon for all available events of a session channel.
1594 * Sets the contents of the events array.
1595 * Returns the number of lttng_event entries in events;
1596 * on error, returns a negative value.
1597 */
1598 int lttng_list_events(struct lttng_handle *handle,
1599 const char *channel_name, struct lttng_event **events)
1600 {
1601 int ret;
1602 struct lttcomm_session_msg lsm;
1603
1604 /* Safety check. An handle and channel name are mandatory */
1605 if (handle == NULL || channel_name == NULL) {
1606 return -LTTNG_ERR_INVALID;
1607 }
1608
1609 memset(&lsm, 0, sizeof(lsm));
1610 lsm.cmd_type = LTTNG_LIST_EVENTS;
1611 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1612 sizeof(lsm.session.name));
1613 lttng_ctl_copy_string(lsm.u.list.channel_name, channel_name,
1614 sizeof(lsm.u.list.channel_name));
1615
1616 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1617
1618 ret = lttng_ctl_ask_sessiond(&lsm, (void**) events);
1619 if (ret < 0) {
1620 return ret;
1621 }
1622
1623 return ret / sizeof(struct lttng_event);
1624 }
1625
1626 /*
1627 * Sets the tracing_group variable with name.
1628 * This function allocates memory pointed to by tracing_group.
1629 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1630 */
1631 int lttng_set_tracing_group(const char *name)
1632 {
1633 if (name == NULL) {
1634 return -LTTNG_ERR_INVALID;
1635 }
1636
1637 if (asprintf(&tracing_group, "%s", name) < 0) {
1638 return -LTTNG_ERR_FATAL;
1639 }
1640
1641 return 0;
1642 }
1643
1644 /*
1645 * Returns size of returned session payload data or a negative error code.
1646 */
1647 int lttng_calibrate(struct lttng_handle *handle,
1648 struct lttng_calibrate *calibrate)
1649 {
1650 struct lttcomm_session_msg lsm;
1651
1652 /* Safety check. NULL pointer are forbidden */
1653 if (handle == NULL || calibrate == NULL) {
1654 return -LTTNG_ERR_INVALID;
1655 }
1656
1657 memset(&lsm, 0, sizeof(lsm));
1658 lsm.cmd_type = LTTNG_CALIBRATE;
1659 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1660
1661 memcpy(&lsm.u.calibrate, calibrate, sizeof(lsm.u.calibrate));
1662
1663 return lttng_ctl_ask_sessiond(&lsm, NULL);
1664 }
1665
1666 /*
1667 * Set default channel attributes.
1668 * If either or both of the arguments are null, attr content is zeroe'd.
1669 */
1670 void lttng_channel_set_default_attr(struct lttng_domain *domain,
1671 struct lttng_channel_attr *attr)
1672 {
1673 /* Safety check */
1674 if (attr == NULL || domain == NULL) {
1675 return;
1676 }
1677
1678 memset(attr, 0, sizeof(struct lttng_channel_attr));
1679
1680 /* Same for all domains. */
1681 attr->overwrite = DEFAULT_CHANNEL_OVERWRITE;
1682 attr->tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
1683 attr->tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT;
1684
1685 switch (domain->type) {
1686 case LTTNG_DOMAIN_KERNEL:
1687 attr->switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
1688 attr->read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
1689 attr->subbuf_size = default_get_kernel_channel_subbuf_size();
1690 attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM;
1691 attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
1692 break;
1693 case LTTNG_DOMAIN_UST:
1694 switch (domain->buf_type) {
1695 case LTTNG_BUFFER_PER_UID:
1696 attr->subbuf_size = default_get_ust_uid_channel_subbuf_size();
1697 attr->num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM;
1698 attr->output = DEFAULT_UST_UID_CHANNEL_OUTPUT;
1699 attr->switch_timer_interval = DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER;
1700 attr->read_timer_interval = DEFAULT_UST_UID_CHANNEL_READ_TIMER;
1701 break;
1702 case LTTNG_BUFFER_PER_PID:
1703 default:
1704 attr->subbuf_size = default_get_ust_pid_channel_subbuf_size();
1705 attr->num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM;
1706 attr->output = DEFAULT_UST_PID_CHANNEL_OUTPUT;
1707 attr->switch_timer_interval = DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER;
1708 attr->read_timer_interval = DEFAULT_UST_PID_CHANNEL_READ_TIMER;
1709 break;
1710 }
1711 default:
1712 /* Default behavior: leave set to 0. */
1713 break;
1714 }
1715 }
1716
1717 /*
1718 * Check if session daemon is alive.
1719 *
1720 * Return 1 if alive or 0 if not.
1721 * On error returns a negative value.
1722 */
1723 int lttng_session_daemon_alive(void)
1724 {
1725 int ret;
1726
1727 ret = set_session_daemon_path();
1728 if (ret < 0) {
1729 /* Error */
1730 return ret;
1731 }
1732
1733 if (*sessiond_sock_path == '\0') {
1734 /*
1735 * No socket path set. Weird error which means the constructor was not
1736 * called.
1737 */
1738 assert(0);
1739 }
1740
1741 ret = try_connect_sessiond(sessiond_sock_path);
1742 if (ret < 0) {
1743 /* Not alive */
1744 return 0;
1745 }
1746
1747 /* Is alive */
1748 return 1;
1749 }
1750
1751 /*
1752 * Set URL for a consumer for a session and domain.
1753 *
1754 * Return 0 on success, else a negative value.
1755 */
1756 int lttng_set_consumer_url(struct lttng_handle *handle,
1757 const char *control_url, const char *data_url)
1758 {
1759 int ret;
1760 ssize_t size;
1761 struct lttcomm_session_msg lsm;
1762 struct lttng_uri *uris = NULL;
1763
1764 if (handle == NULL || (control_url == NULL && data_url == NULL)) {
1765 return -LTTNG_ERR_INVALID;
1766 }
1767
1768 memset(&lsm, 0, sizeof(lsm));
1769
1770 lsm.cmd_type = LTTNG_SET_CONSUMER_URI;
1771
1772 lttng_ctl_copy_string(lsm.session.name, handle->session_name,
1773 sizeof(lsm.session.name));
1774 lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
1775
1776 size = uri_parse_str_urls(control_url, data_url, &uris);
1777 if (size < 0) {
1778 return -LTTNG_ERR_INVALID;
1779 }
1780
1781 lsm.u.uri.size = size;
1782
1783 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1784 sizeof(struct lttng_uri) * size, NULL);
1785
1786 free(uris);
1787 return ret;
1788 }
1789
1790 /*
1791 * [OBSOLETE]
1792 */
1793 int lttng_enable_consumer(struct lttng_handle *handle)
1794 {
1795 return -ENOSYS;
1796 }
1797
1798 /*
1799 * [OBSOLETE]
1800 */
1801 int lttng_disable_consumer(struct lttng_handle *handle)
1802 {
1803 return -ENOSYS;
1804 }
1805
1806 /*
1807 * This is an extension of create session that is ONLY and SHOULD only be used
1808 * by the lttng command line program. It exists to avoid using URI parsing in
1809 * the lttng client.
1810 *
1811 * We need the date and time for the trace path subdirectory for the case where
1812 * the user does NOT define one using either -o or -U. Using the normal
1813 * lttng_create_session API call, we have no clue on the session daemon side if
1814 * the URL was generated automatically by the client or define by the user.
1815 *
1816 * So this function "wrapper" is hidden from the public API, takes the datetime
1817 * string and appends it if necessary to the URI subdirectory before sending it
1818 * to the session daemon.
1819 *
1820 * With this extra function, the lttng_create_session call behavior is not
1821 * changed and the timestamp is appended to the URI on the session daemon side
1822 * if necessary.
1823 */
1824 int _lttng_create_session_ext(const char *name, const char *url,
1825 const char *datetime)
1826 {
1827 int ret;
1828 ssize_t size;
1829 struct lttcomm_session_msg lsm;
1830 struct lttng_uri *uris = NULL;
1831
1832 if (name == NULL || datetime == NULL) {
1833 return -LTTNG_ERR_INVALID;
1834 }
1835
1836 memset(&lsm, 0, sizeof(lsm));
1837
1838 lsm.cmd_type = LTTNG_CREATE_SESSION;
1839 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1840
1841 /* There should never be a data URL */
1842 size = uri_parse_str_urls(url, NULL, &uris);
1843 if (size < 0) {
1844 ret = -LTTNG_ERR_INVALID;
1845 goto error;
1846 }
1847
1848 lsm.u.uri.size = size;
1849
1850 if (size > 0 && uris[0].dtype != LTTNG_DST_PATH && strlen(uris[0].subdir) == 0) {
1851 /* Don't append datetime if the name was automatically created. */
1852 if (strncmp(name, DEFAULT_SESSION_NAME "-",
1853 strlen(DEFAULT_SESSION_NAME) + 1)) {
1854 ret = snprintf(uris[0].subdir, sizeof(uris[0].subdir), "%s-%s",
1855 name, datetime);
1856 } else {
1857 ret = snprintf(uris[0].subdir, sizeof(uris[0].subdir), "%s", name);
1858 }
1859 if (ret < 0) {
1860 PERROR("snprintf uri subdir");
1861 ret = -LTTNG_ERR_FATAL;
1862 goto error;
1863 }
1864 }
1865
1866 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1867 sizeof(struct lttng_uri) * size, NULL);
1868
1869 error:
1870 free(uris);
1871 return ret;
1872 }
1873
1874 /*
1875 * For a given session name, this call checks if the data is ready to be read
1876 * or is still being extracted by the consumer(s) hence not ready to be used by
1877 * any readers.
1878 */
1879 int lttng_data_pending(const char *session_name)
1880 {
1881 int ret;
1882 struct lttcomm_session_msg lsm;
1883
1884 if (session_name == NULL) {
1885 return -LTTNG_ERR_INVALID;
1886 }
1887
1888 memset(&lsm, 0, sizeof(lsm));
1889 lsm.cmd_type = LTTNG_DATA_PENDING;
1890
1891 lttng_ctl_copy_string(lsm.session.name, session_name,
1892 sizeof(lsm.session.name));
1893
1894 ret = lttng_ctl_ask_sessiond(&lsm, NULL);
1895
1896 /*
1897 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1898 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1899 * that the data is available. Yes it is hackish but for now this is the
1900 * only way.
1901 */
1902 if (ret == -1) {
1903 ret = 1;
1904 }
1905
1906 return ret;
1907 }
1908
1909 /*
1910 * Create a session exclusively used for snapshot.
1911 *
1912 * Returns LTTNG_OK on success or a negative error code.
1913 */
1914 int lttng_create_session_snapshot(const char *name, const char *snapshot_url)
1915 {
1916 int ret;
1917 ssize_t size;
1918 struct lttcomm_session_msg lsm;
1919 struct lttng_uri *uris = NULL;
1920
1921 if (name == NULL) {
1922 return -LTTNG_ERR_INVALID;
1923 }
1924
1925 memset(&lsm, 0, sizeof(lsm));
1926
1927 lsm.cmd_type = LTTNG_CREATE_SESSION_SNAPSHOT;
1928 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1929
1930 size = uri_parse_str_urls(snapshot_url, NULL, &uris);
1931 if (size < 0) {
1932 return -LTTNG_ERR_INVALID;
1933 }
1934
1935 lsm.u.uri.size = size;
1936
1937 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1938 sizeof(struct lttng_uri) * size, NULL);
1939
1940 free(uris);
1941 return ret;
1942 }
1943
1944 /*
1945 * Create a session exclusively used for live.
1946 *
1947 * Returns LTTNG_OK on success or a negative error code.
1948 */
1949 int lttng_create_session_live(const char *name, const char *url,
1950 unsigned int timer_interval)
1951 {
1952 int ret;
1953 ssize_t size;
1954 struct lttcomm_session_msg lsm;
1955 struct lttng_uri *uris = NULL;
1956
1957 if (name == NULL) {
1958 return -LTTNG_ERR_INVALID;
1959 }
1960
1961 memset(&lsm, 0, sizeof(lsm));
1962
1963 lsm.cmd_type = LTTNG_CREATE_SESSION_LIVE;
1964 lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
1965
1966 if (url) {
1967 size = uri_parse_str_urls(url, NULL, &uris);
1968 if (size <= 0) {
1969 ret = -LTTNG_ERR_INVALID;
1970 goto end;
1971 }
1972
1973 /* file:// is not accepted for live session. */
1974 if (uris[0].dtype == LTTNG_DST_PATH) {
1975 ret = -LTTNG_ERR_INVALID;
1976 goto end;
1977 }
1978 } else {
1979 size = 0;
1980 }
1981
1982 lsm.u.session_live.nb_uri = size;
1983 lsm.u.session_live.timer_interval = timer_interval;
1984
1985 ret = lttng_ctl_ask_sessiond_varlen(&lsm, uris,
1986 sizeof(struct lttng_uri) * size, NULL);
1987
1988 end:
1989 free(uris);
1990 return ret;
1991 }
1992
1993 /*
1994 * lib constructor
1995 */
1996 static void __attribute__((constructor)) init()
1997 {
1998 /* Set default session group */
1999 lttng_set_tracing_group(DEFAULT_TRACING_GROUP);
2000 }
2001
2002 /*
2003 * lib destructor
2004 */
2005 static void __attribute__((destructor)) lttng_ctl_exit()
2006 {
2007 free(tracing_group);
2008 }
LTTng 2.0 tools and control repository
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