4 * Linux Trace Toolkit Control Library
6 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
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.
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.
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
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>
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"
46 static const int print_xml
= 1;
47 #define dbg_printf(fmt, args...) \
48 printf("[debug liblttng-ctl] " fmt, ## args)
50 static const int print_xml
= 0;
51 #define dbg_printf(fmt, args...) \
53 /* do nothing but check printf format */ \
55 printf("[debug liblttnctl] " fmt, ## args); \
60 /* Socket to session daemon for communication */
61 static int sessiond_socket
;
62 static char sessiond_sock_path
[PATH_MAX
];
65 static char *tracing_group
;
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.
76 int lttng_opt_verbose
;
80 * Copy string from src to dst and enforce null terminated byte.
83 void lttng_ctl_copy_string(char *dst
, const char *src
, size_t len
)
86 strncpy(dst
, src
, len
);
87 /* Enforce the NULL terminated byte */
95 * Copy domain to lttcomm_session_msg domain.
97 * If domain is unknown, default domain will be the kernel.
100 void lttng_ctl_copy_lttng_domain(struct lttng_domain
*dst
,
101 struct lttng_domain
*src
)
105 case LTTNG_DOMAIN_KERNEL
:
106 case LTTNG_DOMAIN_UST
:
107 case LTTNG_DOMAIN_JUL
:
108 memcpy(dst
, src
, sizeof(struct lttng_domain
));
111 memset(dst
, 0, sizeof(struct lttng_domain
));
118 * Send lttcomm_session_msg to the session daemon.
120 * On success, returns the number of bytes sent (>=0)
121 * On error, returns -1
123 static int send_session_msg(struct lttcomm_session_msg
*lsm
)
128 ret
= -LTTNG_ERR_NO_SESSIOND
;
132 DBG("LSM cmd type : %d", lsm
->cmd_type
);
134 ret
= lttcomm_send_creds_unix_sock(sessiond_socket
, lsm
,
135 sizeof(struct lttcomm_session_msg
));
137 ret
= -LTTNG_ERR_FATAL
;
145 * Send var len data to the session daemon.
147 * On success, returns the number of bytes sent (>=0)
148 * On error, returns -1
150 static int send_session_varlen(void *data
, size_t len
)
155 ret
= -LTTNG_ERR_NO_SESSIOND
;
164 ret
= lttcomm_send_unix_sock(sessiond_socket
, data
, len
);
166 ret
= -LTTNG_ERR_FATAL
;
174 * Receive data from the sessiond socket.
176 * On success, returns the number of bytes received (>=0)
177 * On error, returns -1 (recvmsg() error) or -ENOTCONN
179 static int recv_data_sessiond(void *buf
, size_t len
)
184 ret
= -LTTNG_ERR_NO_SESSIOND
;
188 ret
= lttcomm_recv_unix_sock(sessiond_socket
, buf
, len
);
190 ret
= -LTTNG_ERR_FATAL
;
198 * Check if we are in the specified group.
200 * If yes return 1, else return -1.
203 int lttng_check_tracing_group(void)
205 struct group
*grp_tracing
; /* no free(). See getgrnam(3) */
207 int grp_list_size
, grp_id
, i
;
209 const char *grp_name
= tracing_group
;
211 /* Get GID of group 'tracing' */
212 grp_tracing
= getgrnam(grp_name
);
214 /* If grp_tracing is NULL, the group does not exist. */
218 /* Get number of supplementary group IDs */
219 grp_list_size
= getgroups(0, NULL
);
220 if (grp_list_size
< 0) {
225 /* Alloc group list of the right size */
226 grp_list
= malloc(grp_list_size
* sizeof(gid_t
));
231 grp_id
= getgroups(grp_list_size
, grp_list
);
237 for (i
= 0; i
< grp_list_size
; i
++) {
238 if (grp_list
[i
] == grp_tracing
->gr_gid
) {
252 * Try connect to session daemon with sock_path.
254 * Return 0 on success, else -1
256 static int try_connect_sessiond(const char *sock_path
)
260 /* If socket exist, we check if the daemon listens for connect. */
261 ret
= access(sock_path
, F_OK
);
267 ret
= lttcomm_connect_unix_sock(sock_path
);
273 ret
= lttcomm_close_unix_sock(ret
);
275 perror("lttcomm_close_unix_sock");
285 * Set sessiond socket path by putting it in the global sessiond_sock_path
288 * Returns 0 on success, negative value on failure (the sessiond socket path
289 * is somehow too long or ENOMEM).
291 static int set_session_daemon_path(void)
293 int in_tgroup
= 0; /* In tracing group */
299 /* Are we in the tracing group ? */
300 in_tgroup
= lttng_check_tracing_group();
303 if ((uid
== 0) || in_tgroup
) {
304 lttng_ctl_copy_string(sessiond_sock_path
,
305 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
, sizeof(sessiond_sock_path
));
313 ret
= try_connect_sessiond(sessiond_sock_path
);
317 /* Global session daemon not available... */
319 /* ...or not in tracing group (and not root), default */
322 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
323 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
325 ret
= snprintf(sessiond_sock_path
, sizeof(sessiond_sock_path
),
326 DEFAULT_HOME_CLIENT_UNIX_SOCK
, utils_get_home_dir());
327 if ((ret
< 0) || (ret
>= sizeof(sessiond_sock_path
))) {
339 * Connect to the LTTng session daemon.
341 * On success, return 0. On error, return -1.
343 static int connect_sessiond(void)
347 /* Don't try to connect if already connected. */
352 ret
= set_session_daemon_path();
357 /* Connect to the sesssion daemon */
358 ret
= lttcomm_connect_unix_sock(sessiond_sock_path
);
363 sessiond_socket
= ret
;
373 * Clean disconnect from the session daemon.
374 * On success, return 0. On error, return -1.
376 static int disconnect_sessiond(void)
381 ret
= lttcomm_close_unix_sock(sessiond_socket
);
390 * Ask the session daemon a specific command and put the data into buf.
391 * Takes extra var. len. data as input to send to the session daemon.
393 * Return size of data (only payload, not header) or a negative error code.
396 int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg
*lsm
,
397 void *vardata
, size_t varlen
, void **buf
)
402 struct lttcomm_lttng_msg llm
;
404 ret
= connect_sessiond();
406 ret
= -LTTNG_ERR_NO_SESSIOND
;
410 /* Send command to session daemon */
411 ret
= send_session_msg(lsm
);
413 /* Ret value is a valid lttng error code. */
416 /* Send var len data */
417 ret
= send_session_varlen(vardata
, varlen
);
419 /* Ret value is a valid lttng error code. */
423 /* Get header from data transmission */
424 ret
= recv_data_sessiond(&llm
, sizeof(llm
));
426 /* Ret value is a valid lttng error code. */
430 /* Check error code if OK */
431 if (llm
.ret_code
!= LTTNG_OK
) {
436 size
= llm
.data_size
;
438 /* If client free with size 0 */
446 data
= (void*) malloc(size
);
448 /* Get payload data */
449 ret
= recv_data_sessiond(data
, size
);
456 * Extra protection not to dereference a NULL pointer. If buf is NULL at
457 * this point, an error is returned and data is freed.
460 ret
= -LTTNG_ERR_INVALID
;
469 disconnect_sessiond();
474 * Create lttng handle and return pointer.
475 * The returned pointer will be NULL in case of malloc() error.
477 struct lttng_handle
*lttng_create_handle(const char *session_name
,
478 struct lttng_domain
*domain
)
480 struct lttng_handle
*handle
= NULL
;
482 if (domain
== NULL
) {
486 handle
= malloc(sizeof(struct lttng_handle
));
487 if (handle
== NULL
) {
488 PERROR("malloc handle");
492 /* Copy session name */
493 lttng_ctl_copy_string(handle
->session_name
, session_name
,
494 sizeof(handle
->session_name
));
496 /* Copy lttng domain */
497 lttng_ctl_copy_lttng_domain(&handle
->domain
, domain
);
504 * Destroy handle by free(3) the pointer.
506 void lttng_destroy_handle(struct lttng_handle
*handle
)
512 * Register an outside consumer.
513 * Returns size of returned session payload data or a negative error code.
515 int lttng_register_consumer(struct lttng_handle
*handle
,
516 const char *socket_path
)
518 struct lttcomm_session_msg lsm
;
520 if (handle
== NULL
|| socket_path
== NULL
) {
521 return -LTTNG_ERR_INVALID
;
524 memset(&lsm
, 0, sizeof(lsm
));
525 lsm
.cmd_type
= LTTNG_REGISTER_CONSUMER
;
526 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
527 sizeof(lsm
.session
.name
));
528 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
530 lttng_ctl_copy_string(lsm
.u
.reg
.path
, socket_path
, sizeof(lsm
.u
.reg
.path
));
532 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
536 * Start tracing for all traces of the session.
537 * Returns size of returned session payload data or a negative error code.
539 int lttng_start_tracing(const char *session_name
)
541 struct lttcomm_session_msg lsm
;
543 if (session_name
== NULL
) {
544 return -LTTNG_ERR_INVALID
;
547 memset(&lsm
, 0, sizeof(lsm
));
548 lsm
.cmd_type
= LTTNG_START_TRACE
;
550 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
551 sizeof(lsm
.session
.name
));
553 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
557 * Stop tracing for all traces of the session.
559 static int _lttng_stop_tracing(const char *session_name
, int wait
)
562 struct lttcomm_session_msg lsm
;
564 if (session_name
== NULL
) {
565 return -LTTNG_ERR_INVALID
;
568 memset(&lsm
, 0, sizeof(lsm
));
569 lsm
.cmd_type
= LTTNG_STOP_TRACE
;
571 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
572 sizeof(lsm
.session
.name
));
574 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
575 if (ret
< 0 && ret
!= -LTTNG_ERR_TRACE_ALREADY_STOPPED
) {
583 /* Check for data availability */
585 data_ret
= lttng_data_pending(session_name
);
587 /* Return the data available call error. */
593 * Data sleep time before retrying (in usec). Don't sleep if the call
594 * returned value indicates availability.
597 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME
);
599 } while (data_ret
!= 0);
607 * Stop tracing and wait for data availability.
609 int lttng_stop_tracing(const char *session_name
)
611 return _lttng_stop_tracing(session_name
, 1);
615 * Stop tracing but _don't_ wait for data availability.
617 int lttng_stop_tracing_no_wait(const char *session_name
)
619 return _lttng_stop_tracing(session_name
, 0);
623 * Add context to a channel.
625 * If the given channel is NULL, add the contexts to all channels.
626 * The event_name param is ignored.
628 * Returns the size of the returned payload data or a negative error code.
630 int lttng_add_context(struct lttng_handle
*handle
,
631 struct lttng_event_context
*ctx
, const char *event_name
,
632 const char *channel_name
)
634 struct lttcomm_session_msg lsm
;
636 /* Safety check. Both are mandatory */
637 if (handle
== NULL
|| ctx
== NULL
) {
638 return -LTTNG_ERR_INVALID
;
641 memset(&lsm
, 0, sizeof(lsm
));
643 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
645 /* If no channel name, send empty string. */
646 if (channel_name
== NULL
) {
647 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, "",
648 sizeof(lsm
.u
.context
.channel_name
));
650 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, channel_name
,
651 sizeof(lsm
.u
.context
.channel_name
));
654 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
656 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
658 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
659 sizeof(lsm
.session
.name
));
661 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
665 * Enable event(s) for a channel.
666 * If no event name is specified, all events are enabled.
667 * If no channel name is specified, the default 'channel0' is used.
668 * Returns size of returned session payload data or a negative error code.
670 int lttng_enable_event(struct lttng_handle
*handle
,
671 struct lttng_event
*ev
, const char *channel_name
)
673 return lttng_enable_event_with_exclusions(handle
, ev
, channel_name
,
678 * Create or enable an event with a filter expression.
680 * Return negative error value on error.
681 * Return size of returned session payload data if OK.
683 int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
684 struct lttng_event
*event
, const char *channel_name
,
685 const char *filter_expression
)
687 return lttng_enable_event_with_exclusions(handle
, event
, channel_name
,
688 filter_expression
, 0, NULL
);
692 * Depending on the event, return a newly allocated JUL filter expression or
693 * NULL if not applicable.
695 * An event with NO loglevel and the name is * will return NULL.
697 static char *set_jul_filter(const char *filter
, struct lttng_event
*ev
)
700 char *jul_filter
= NULL
;
704 /* Don't add filter for the '*' event. */
705 if (ev
->name
[0] != '*') {
707 err
= asprintf(&jul_filter
, "%s && logger_name == \"%s\"", filter
,
710 err
= asprintf(&jul_filter
, "logger_name == \"%s\"", ev
->name
);
718 /* Add loglevel filtering if any for the JUL domain. */
719 if (ev
->loglevel_type
!= LTTNG_EVENT_LOGLEVEL_ALL
) {
722 if (ev
->loglevel_type
== LTTNG_EVENT_LOGLEVEL_RANGE
) {
728 if (filter
|| jul_filter
) {
731 err
= asprintf(&new_filter
, "%s && int_loglevel %s %d",
732 jul_filter
? jul_filter
: filter
, op
,
737 jul_filter
= new_filter
;
739 err
= asprintf(&jul_filter
, "int_loglevel %s %d", op
,
755 * Generate the filter bytecode from a give filter expression string. Put the
756 * newly allocated parser context in ctxp and populate the lsm object with the
759 * Return 0 on success else a LTTNG_ERR_* code and ctxp is untouched.
761 static int generate_filter(char *filter_expression
,
762 struct lttcomm_session_msg
*lsm
, struct filter_parser_ctx
**ctxp
)
765 struct filter_parser_ctx
*ctx
= NULL
;
768 assert(filter_expression
);
773 * Casting const to non-const, as the underlying function will use it in
776 fmem
= lttng_fmemopen((void *) filter_expression
,
777 strlen(filter_expression
), "r");
779 fprintf(stderr
, "Error opening memory as stream\n");
780 ret
= -LTTNG_ERR_FILTER_NOMEM
;
783 ctx
= filter_parser_ctx_alloc(fmem
);
785 fprintf(stderr
, "Error allocating parser\n");
786 ret
= -LTTNG_ERR_FILTER_NOMEM
;
787 goto filter_alloc_error
;
789 ret
= filter_parser_ctx_append_ast(ctx
);
791 fprintf(stderr
, "Parse error\n");
792 ret
= -LTTNG_ERR_FILTER_INVAL
;
795 ret
= filter_visitor_set_parent(ctx
);
797 fprintf(stderr
, "Set parent error\n");
798 ret
= -LTTNG_ERR_FILTER_INVAL
;
802 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
805 fprintf(stderr
, "XML print error\n");
806 ret
= -LTTNG_ERR_FILTER_INVAL
;
811 dbg_printf("Generating IR... ");
813 ret
= filter_visitor_ir_generate(ctx
);
815 fprintf(stderr
, "Generate IR error\n");
816 ret
= -LTTNG_ERR_FILTER_INVAL
;
819 dbg_printf("done\n");
821 dbg_printf("Validating IR... ");
823 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
825 ret
= -LTTNG_ERR_FILTER_INVAL
;
828 /* Validate strings used as literals in the expression */
829 ret
= filter_visitor_ir_validate_string(ctx
);
831 ret
= -LTTNG_ERR_FILTER_INVAL
;
834 dbg_printf("done\n");
836 dbg_printf("Generating bytecode... ");
838 ret
= filter_visitor_bytecode_generate(ctx
);
840 fprintf(stderr
, "Generate bytecode error\n");
841 ret
= -LTTNG_ERR_FILTER_INVAL
;
844 dbg_printf("done\n");
845 dbg_printf("Size of bytecode generated: %u bytes.\n",
846 bytecode_get_len(&ctx
->bytecode
->b
));
848 lsm
->u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
849 + bytecode_get_len(&ctx
->bytecode
->b
);
850 lsm
->u
.enable
.expression_len
= strlen(filter_expression
) + 1;
852 /* No need to keep the memory stream. */
853 if (fclose(fmem
) != 0) {
862 filter_parser_ctx_free(ctx
);
864 if (fclose(fmem
) != 0) {
872 * Enable event(s) for a channel, possibly with exclusions and a filter.
873 * If no event name is specified, all events are enabled.
874 * If no channel name is specified, the default name is used.
875 * If filter expression is not NULL, the filter is set for the event.
876 * If exclusion count is not zero, the exclusions are set for the event.
877 * Returns size of returned session payload data or a negative error code.
879 int lttng_enable_event_with_exclusions(struct lttng_handle
*handle
,
880 struct lttng_event
*ev
, const char *channel_name
,
881 const char *original_filter_expression
,
882 int exclusion_count
, char **exclusion_list
)
884 struct lttcomm_session_msg lsm
;
887 unsigned int free_filter_expression
= 0;
888 struct filter_parser_ctx
*ctx
= NULL
;
890 * Cast as non-const since we may replace the filter expression
891 * by a dynamically allocated string. Otherwise, the original
892 * string is not modified.
894 char *filter_expression
= (char *) original_filter_expression
;
896 if (handle
== NULL
|| ev
== NULL
) {
897 ret
= -LTTNG_ERR_INVALID
;
901 /* Empty filter string will always be rejected by the parser
902 * anyway, so treat this corner-case early to eliminate
903 * lttng_fmemopen error for 0-byte allocation.
905 if (filter_expression
&& filter_expression
[0] == '\0') {
906 ret
= -LTTNG_ERR_INVALID
;
910 memset(&lsm
, 0, sizeof(lsm
));
912 /* If no channel name, send empty string. */
913 if (channel_name
== NULL
) {
914 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, "",
915 sizeof(lsm
.u
.enable
.channel_name
));
917 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
918 sizeof(lsm
.u
.enable
.channel_name
));
921 if (ev
->name
[0] != '\0') {
922 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
924 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
927 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
928 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
930 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
931 sizeof(lsm
.session
.name
));
932 lsm
.u
.enable
.exclusion_count
= exclusion_count
;
933 lsm
.u
.enable
.bytecode_len
= 0;
936 * For the JUL domain, a filter is enforced except for the enable all
937 * event. This is done to avoid having the event in all sessions thus
938 * filtering by logger name.
940 if (exclusion_count
== 0 && filter_expression
== NULL
&&
941 handle
->domain
.type
!= LTTNG_DOMAIN_JUL
) {
946 * We have either a filter or some exclusions, so we need to set up
947 * a variable-length memory block from where to send the data
950 /* Parse filter expression */
951 if (filter_expression
!= NULL
|| handle
->domain
.type
== LTTNG_DOMAIN_JUL
) {
952 if (handle
->domain
.type
== LTTNG_DOMAIN_JUL
) {
955 /* Setup JUL filter if needed. */
956 jul_filter
= set_jul_filter(filter_expression
, ev
);
958 if (!filter_expression
) {
959 /* No JUL and no filter, just skip everything below. */
964 * With a JUL filter, the original filter has been added to it
965 * thus replace the filter expression.
967 filter_expression
= jul_filter
;
968 free_filter_expression
= 1;
972 ret
= generate_filter(filter_expression
, &lsm
, &ctx
);
978 varlen_data
= zmalloc(lsm
.u
.enable
.bytecode_len
979 + lsm
.u
.enable
.expression_len
980 + LTTNG_SYMBOL_NAME_LEN
* exclusion_count
);
982 ret
= -LTTNG_ERR_EXCLUSION_NOMEM
;
986 /* Put exclusion names first in the data */
987 while (exclusion_count
--) {
988 strncpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* exclusion_count
,
989 *(exclusion_list
+ exclusion_count
), LTTNG_SYMBOL_NAME_LEN
);
991 /* Add filter expression next */
992 if (lsm
.u
.enable
.expression_len
!= 0) {
994 + LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
,
996 lsm
.u
.enable
.expression_len
);
998 /* Add filter bytecode next */
999 if (ctx
&& lsm
.u
.enable
.bytecode_len
!= 0) {
1001 + LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
1002 + lsm
.u
.enable
.expression_len
,
1004 lsm
.u
.enable
.bytecode_len
);
1007 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, varlen_data
,
1008 (LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
) +
1009 lsm
.u
.enable
.bytecode_len
+ lsm
.u
.enable
.expression_len
, NULL
);
1013 if (filter_expression
&& ctx
) {
1014 filter_bytecode_free(ctx
);
1015 filter_ir_free(ctx
);
1016 filter_parser_ctx_free(ctx
);
1019 if (free_filter_expression
) {
1021 * The filter expression has been replaced and must be freed as it is
1022 * not the original filter expression received as a parameter.
1024 free(filter_expression
);
1028 * Return directly to the caller and don't ask the sessiond since something
1029 * went wrong in the parsing of data above.
1034 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1039 * Disable event(s) of a channel and domain.
1040 * If no event name is specified, all events are disabled.
1041 * If no channel name is specified, the default 'channel0' is used.
1042 * Returns size of returned session payload data or a negative error code.
1044 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
1045 const char *channel_name
)
1047 struct lttcomm_session_msg lsm
;
1049 if (handle
== NULL
) {
1050 return -LTTNG_ERR_INVALID
;
1053 memset(&lsm
, 0, sizeof(lsm
));
1055 /* If no channel name, send empty string. */
1056 if (channel_name
== NULL
) {
1057 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, "",
1058 sizeof(lsm
.u
.disable
.channel_name
));
1060 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
1061 sizeof(lsm
.u
.disable
.channel_name
));
1064 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1067 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
1068 sizeof(lsm
.u
.disable
.name
));
1069 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
1071 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
1074 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1075 sizeof(lsm
.session
.name
));
1077 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1081 * Enable channel per domain
1082 * Returns size of returned session payload data or a negative error code.
1084 int lttng_enable_channel(struct lttng_handle
*handle
,
1085 struct lttng_channel
*chan
)
1087 struct lttcomm_session_msg lsm
;
1090 * NULL arguments are forbidden. No default values.
1092 if (handle
== NULL
|| chan
== NULL
) {
1093 return -LTTNG_ERR_INVALID
;
1096 memset(&lsm
, 0, sizeof(lsm
));
1098 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
1100 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
1102 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1104 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1105 sizeof(lsm
.session
.name
));
1107 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1111 * All tracing will be stopped for registered events of the channel.
1112 * Returns size of returned session payload data or a negative error code.
1114 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
1116 struct lttcomm_session_msg lsm
;
1118 /* Safety check. Both are mandatory */
1119 if (handle
== NULL
|| name
== NULL
) {
1120 return -LTTNG_ERR_INVALID
;
1123 memset(&lsm
, 0, sizeof(lsm
));
1125 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
1127 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
1128 sizeof(lsm
.u
.disable
.channel_name
));
1130 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1132 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1133 sizeof(lsm
.session
.name
));
1135 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1139 * Lists all available tracepoints of domain.
1140 * Sets the contents of the events array.
1141 * Returns the number of lttng_event entries in events;
1142 * on error, returns a negative value.
1144 int lttng_list_tracepoints(struct lttng_handle
*handle
,
1145 struct lttng_event
**events
)
1148 struct lttcomm_session_msg lsm
;
1150 if (handle
== NULL
) {
1151 return -LTTNG_ERR_INVALID
;
1154 memset(&lsm
, 0, sizeof(lsm
));
1155 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1156 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1158 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
1163 return ret
/ sizeof(struct lttng_event
);
1167 * Lists all available tracepoint fields of domain.
1168 * Sets the contents of the event field array.
1169 * Returns the number of lttng_event_field entries in events;
1170 * on error, returns a negative value.
1172 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1173 struct lttng_event_field
**fields
)
1176 struct lttcomm_session_msg lsm
;
1178 if (handle
== NULL
) {
1179 return -LTTNG_ERR_INVALID
;
1182 memset(&lsm
, 0, sizeof(lsm
));
1183 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1184 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1186 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
1191 return ret
/ sizeof(struct lttng_event_field
);
1195 * Returns a human readable string describing
1196 * the error code (a negative value).
1198 const char *lttng_strerror(int code
)
1200 return error_get_str(code
);
1204 * Create a brand new session using name and url for destination.
1206 * Returns LTTNG_OK on success or a negative error code.
1208 int lttng_create_session(const char *name
, const char *url
)
1212 struct lttcomm_session_msg lsm
;
1213 struct lttng_uri
*uris
= NULL
;
1216 return -LTTNG_ERR_INVALID
;
1219 memset(&lsm
, 0, sizeof(lsm
));
1221 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1222 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1224 /* There should never be a data URL */
1225 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1227 return -LTTNG_ERR_INVALID
;
1230 lsm
.u
.uri
.size
= size
;
1232 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1233 sizeof(struct lttng_uri
) * size
, NULL
);
1240 * Destroy session using name.
1241 * Returns size of returned session payload data or a negative error code.
1243 int lttng_destroy_session(const char *session_name
)
1245 struct lttcomm_session_msg lsm
;
1247 if (session_name
== NULL
) {
1248 return -LTTNG_ERR_INVALID
;
1251 memset(&lsm
, 0, sizeof(lsm
));
1252 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1254 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1255 sizeof(lsm
.session
.name
));
1257 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1261 * Ask the session daemon for all available sessions.
1262 * Sets the contents of the sessions array.
1263 * Returns the number of lttng_session entries in sessions;
1264 * on error, returns a negative value.
1266 int lttng_list_sessions(struct lttng_session
**sessions
)
1269 struct lttcomm_session_msg lsm
;
1271 memset(&lsm
, 0, sizeof(lsm
));
1272 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1273 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1278 return ret
/ sizeof(struct lttng_session
);
1282 * Ask the session daemon for all available domains of a session.
1283 * Sets the contents of the domains array.
1284 * Returns the number of lttng_domain entries in domains;
1285 * on error, returns a negative value.
1287 int lttng_list_domains(const char *session_name
,
1288 struct lttng_domain
**domains
)
1291 struct lttcomm_session_msg lsm
;
1293 if (session_name
== NULL
) {
1294 return -LTTNG_ERR_INVALID
;
1297 memset(&lsm
, 0, sizeof(lsm
));
1298 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1300 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1301 sizeof(lsm
.session
.name
));
1303 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1308 return ret
/ sizeof(struct lttng_domain
);
1312 * Ask the session daemon for all available channels of a session.
1313 * Sets the contents of the channels array.
1314 * Returns the number of lttng_channel entries in channels;
1315 * on error, returns a negative value.
1317 int lttng_list_channels(struct lttng_handle
*handle
,
1318 struct lttng_channel
**channels
)
1321 struct lttcomm_session_msg lsm
;
1323 if (handle
== NULL
) {
1324 return -LTTNG_ERR_INVALID
;
1327 memset(&lsm
, 0, sizeof(lsm
));
1328 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1329 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1330 sizeof(lsm
.session
.name
));
1332 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1334 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1339 return ret
/ sizeof(struct lttng_channel
);
1343 * Ask the session daemon for all available events of a session channel.
1344 * Sets the contents of the events array.
1345 * Returns the number of lttng_event entries in events;
1346 * on error, returns a negative value.
1348 int lttng_list_events(struct lttng_handle
*handle
,
1349 const char *channel_name
, struct lttng_event
**events
)
1352 struct lttcomm_session_msg lsm
;
1354 /* Safety check. An handle and channel name are mandatory */
1355 if (handle
== NULL
|| channel_name
== NULL
) {
1356 return -LTTNG_ERR_INVALID
;
1359 memset(&lsm
, 0, sizeof(lsm
));
1360 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1361 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1362 sizeof(lsm
.session
.name
));
1363 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1364 sizeof(lsm
.u
.list
.channel_name
));
1366 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1368 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1373 return ret
/ sizeof(struct lttng_event
);
1377 * Sets the tracing_group variable with name.
1378 * This function allocates memory pointed to by tracing_group.
1379 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1381 int lttng_set_tracing_group(const char *name
)
1384 return -LTTNG_ERR_INVALID
;
1387 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1388 return -LTTNG_ERR_FATAL
;
1395 * Returns size of returned session payload data or a negative error code.
1397 int lttng_calibrate(struct lttng_handle
*handle
,
1398 struct lttng_calibrate
*calibrate
)
1400 struct lttcomm_session_msg lsm
;
1402 /* Safety check. NULL pointer are forbidden */
1403 if (handle
== NULL
|| calibrate
== NULL
) {
1404 return -LTTNG_ERR_INVALID
;
1407 memset(&lsm
, 0, sizeof(lsm
));
1408 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1409 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1411 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1413 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1417 * Set default channel attributes.
1418 * If either or both of the arguments are null, attr content is zeroe'd.
1420 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1421 struct lttng_channel_attr
*attr
)
1424 if (attr
== NULL
|| domain
== NULL
) {
1428 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1430 /* Same for all domains. */
1431 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1432 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1433 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1435 switch (domain
->type
) {
1436 case LTTNG_DOMAIN_KERNEL
:
1437 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1438 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1439 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1440 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1441 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1443 case LTTNG_DOMAIN_UST
:
1444 switch (domain
->buf_type
) {
1445 case LTTNG_BUFFER_PER_UID
:
1446 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1447 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1448 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1449 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1450 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1452 case LTTNG_BUFFER_PER_PID
:
1454 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1455 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1456 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1457 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1458 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1462 /* Default behavior: leave set to 0. */
1468 * Check if session daemon is alive.
1470 * Return 1 if alive or 0 if not.
1471 * On error returns a negative value.
1473 int lttng_session_daemon_alive(void)
1477 ret
= set_session_daemon_path();
1483 if (*sessiond_sock_path
== '\0') {
1485 * No socket path set. Weird error which means the constructor was not
1491 ret
= try_connect_sessiond(sessiond_sock_path
);
1502 * Set URL for a consumer for a session and domain.
1504 * Return 0 on success, else a negative value.
1506 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1507 const char *control_url
, const char *data_url
)
1511 struct lttcomm_session_msg lsm
;
1512 struct lttng_uri
*uris
= NULL
;
1514 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1515 return -LTTNG_ERR_INVALID
;
1518 memset(&lsm
, 0, sizeof(lsm
));
1520 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1522 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1523 sizeof(lsm
.session
.name
));
1524 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1526 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1528 return -LTTNG_ERR_INVALID
;
1531 lsm
.u
.uri
.size
= size
;
1533 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1534 sizeof(struct lttng_uri
) * size
, NULL
);
1543 int lttng_enable_consumer(struct lttng_handle
*handle
)
1551 int lttng_disable_consumer(struct lttng_handle
*handle
)
1557 * This is an extension of create session that is ONLY and SHOULD only be used
1558 * by the lttng command line program. It exists to avoid using URI parsing in
1561 * We need the date and time for the trace path subdirectory for the case where
1562 * the user does NOT define one using either -o or -U. Using the normal
1563 * lttng_create_session API call, we have no clue on the session daemon side if
1564 * the URL was generated automatically by the client or define by the user.
1566 * So this function "wrapper" is hidden from the public API, takes the datetime
1567 * string and appends it if necessary to the URI subdirectory before sending it
1568 * to the session daemon.
1570 * With this extra function, the lttng_create_session call behavior is not
1571 * changed and the timestamp is appended to the URI on the session daemon side
1574 int _lttng_create_session_ext(const char *name
, const char *url
,
1575 const char *datetime
)
1579 struct lttcomm_session_msg lsm
;
1580 struct lttng_uri
*uris
= NULL
;
1582 if (name
== NULL
|| datetime
== NULL
) {
1583 return -LTTNG_ERR_INVALID
;
1586 memset(&lsm
, 0, sizeof(lsm
));
1588 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1589 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1591 /* There should never be a data URL */
1592 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1594 ret
= -LTTNG_ERR_INVALID
;
1598 lsm
.u
.uri
.size
= size
;
1600 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1601 /* Don't append datetime if the name was automatically created. */
1602 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1603 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1604 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1607 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1610 PERROR("snprintf uri subdir");
1611 ret
= -LTTNG_ERR_FATAL
;
1616 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1617 sizeof(struct lttng_uri
) * size
, NULL
);
1625 * For a given session name, this call checks if the data is ready to be read
1626 * or is still being extracted by the consumer(s) hence not ready to be used by
1629 int lttng_data_pending(const char *session_name
)
1632 struct lttcomm_session_msg lsm
;
1634 if (session_name
== NULL
) {
1635 return -LTTNG_ERR_INVALID
;
1638 memset(&lsm
, 0, sizeof(lsm
));
1639 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1641 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1642 sizeof(lsm
.session
.name
));
1644 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1647 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1648 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1649 * that the data is available. Yes it is hackish but for now this is the
1660 * Create a session exclusively used for snapshot.
1662 * Returns LTTNG_OK on success or a negative error code.
1664 int lttng_create_session_snapshot(const char *name
, const char *snapshot_url
)
1668 struct lttcomm_session_msg lsm
;
1669 struct lttng_uri
*uris
= NULL
;
1672 return -LTTNG_ERR_INVALID
;
1675 memset(&lsm
, 0, sizeof(lsm
));
1677 lsm
.cmd_type
= LTTNG_CREATE_SESSION_SNAPSHOT
;
1678 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1680 size
= uri_parse_str_urls(snapshot_url
, NULL
, &uris
);
1682 return -LTTNG_ERR_INVALID
;
1685 lsm
.u
.uri
.size
= size
;
1687 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1688 sizeof(struct lttng_uri
) * size
, NULL
);
1695 * Create a session exclusively used for live.
1697 * Returns LTTNG_OK on success or a negative error code.
1699 int lttng_create_session_live(const char *name
, const char *url
,
1700 unsigned int timer_interval
)
1704 struct lttcomm_session_msg lsm
;
1705 struct lttng_uri
*uris
= NULL
;
1708 return -LTTNG_ERR_INVALID
;
1711 memset(&lsm
, 0, sizeof(lsm
));
1713 lsm
.cmd_type
= LTTNG_CREATE_SESSION_LIVE
;
1714 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1717 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1719 ret
= -LTTNG_ERR_INVALID
;
1723 /* file:// is not accepted for live session. */
1724 if (uris
[0].dtype
== LTTNG_DST_PATH
) {
1725 ret
= -LTTNG_ERR_INVALID
;
1732 lsm
.u
.session_live
.nb_uri
= size
;
1733 lsm
.u
.session_live
.timer_interval
= timer_interval
;
1735 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1736 sizeof(struct lttng_uri
) * size
, NULL
);
1746 static void __attribute__((constructor
)) init()
1748 /* Set default session group */
1749 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1755 static void __attribute__((destructor
)) lttng_ctl_exit()
1757 free(tracing_group
);