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 case LTTNG_DOMAIN_LOG4J
:
109 memcpy(dst
, src
, sizeof(struct lttng_domain
));
112 memset(dst
, 0, sizeof(struct lttng_domain
));
119 * Send lttcomm_session_msg to the session daemon.
121 * On success, returns the number of bytes sent (>=0)
122 * On error, returns -1
124 static int send_session_msg(struct lttcomm_session_msg
*lsm
)
129 ret
= -LTTNG_ERR_NO_SESSIOND
;
133 DBG("LSM cmd type : %d", lsm
->cmd_type
);
135 ret
= lttcomm_send_creds_unix_sock(sessiond_socket
, lsm
,
136 sizeof(struct lttcomm_session_msg
));
138 ret
= -LTTNG_ERR_FATAL
;
146 * Send var len data to the session daemon.
148 * On success, returns the number of bytes sent (>=0)
149 * On error, returns -1
151 static int send_session_varlen(void *data
, size_t len
)
156 ret
= -LTTNG_ERR_NO_SESSIOND
;
165 ret
= lttcomm_send_unix_sock(sessiond_socket
, data
, len
);
167 ret
= -LTTNG_ERR_FATAL
;
175 * Receive data from the sessiond socket.
177 * On success, returns the number of bytes received (>=0)
178 * On error, returns -1 (recvmsg() error) or -ENOTCONN
180 static int recv_data_sessiond(void *buf
, size_t len
)
185 ret
= -LTTNG_ERR_NO_SESSIOND
;
189 ret
= lttcomm_recv_unix_sock(sessiond_socket
, buf
, len
);
191 ret
= -LTTNG_ERR_FATAL
;
199 * Check if we are in the specified group.
201 * If yes return 1, else return -1.
204 int lttng_check_tracing_group(void)
206 struct group
*grp_tracing
; /* no free(). See getgrnam(3) */
208 int grp_list_size
, grp_id
, i
;
210 const char *grp_name
= tracing_group
;
212 /* Get GID of group 'tracing' */
213 grp_tracing
= getgrnam(grp_name
);
215 /* If grp_tracing is NULL, the group does not exist. */
219 /* Get number of supplementary group IDs */
220 grp_list_size
= getgroups(0, NULL
);
221 if (grp_list_size
< 0) {
226 /* Alloc group list of the right size */
227 grp_list
= malloc(grp_list_size
* sizeof(gid_t
));
232 grp_id
= getgroups(grp_list_size
, grp_list
);
238 for (i
= 0; i
< grp_list_size
; i
++) {
239 if (grp_list
[i
] == grp_tracing
->gr_gid
) {
253 * Try connect to session daemon with sock_path.
255 * Return 0 on success, else -1
257 static int try_connect_sessiond(const char *sock_path
)
261 /* If socket exist, we check if the daemon listens for connect. */
262 ret
= access(sock_path
, F_OK
);
268 ret
= lttcomm_connect_unix_sock(sock_path
);
274 ret
= lttcomm_close_unix_sock(ret
);
276 perror("lttcomm_close_unix_sock");
286 * Set sessiond socket path by putting it in the global sessiond_sock_path
289 * Returns 0 on success, negative value on failure (the sessiond socket path
290 * is somehow too long or ENOMEM).
292 static int set_session_daemon_path(void)
294 int in_tgroup
= 0; /* In tracing group */
300 /* Are we in the tracing group ? */
301 in_tgroup
= lttng_check_tracing_group();
304 if ((uid
== 0) || in_tgroup
) {
305 lttng_ctl_copy_string(sessiond_sock_path
,
306 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
, sizeof(sessiond_sock_path
));
314 ret
= try_connect_sessiond(sessiond_sock_path
);
318 /* Global session daemon not available... */
320 /* ...or not in tracing group (and not root), default */
323 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
324 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
326 ret
= snprintf(sessiond_sock_path
, sizeof(sessiond_sock_path
),
327 DEFAULT_HOME_CLIENT_UNIX_SOCK
, utils_get_home_dir());
328 if ((ret
< 0) || (ret
>= sizeof(sessiond_sock_path
))) {
340 * Connect to the LTTng session daemon.
342 * On success, return 0. On error, return -1.
344 static int connect_sessiond(void)
348 /* Don't try to connect if already connected. */
353 ret
= set_session_daemon_path();
358 /* Connect to the sesssion daemon */
359 ret
= lttcomm_connect_unix_sock(sessiond_sock_path
);
364 sessiond_socket
= ret
;
374 * Clean disconnect from the session daemon.
375 * On success, return 0. On error, return -1.
377 static int disconnect_sessiond(void)
382 ret
= lttcomm_close_unix_sock(sessiond_socket
);
391 * Ask the session daemon a specific command and put the data into buf.
392 * Takes extra var. len. data as input to send to the session daemon.
394 * Return size of data (only payload, not header) or a negative error code.
397 int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg
*lsm
,
398 void *vardata
, size_t varlen
, void **buf
)
403 struct lttcomm_lttng_msg llm
;
405 ret
= connect_sessiond();
407 ret
= -LTTNG_ERR_NO_SESSIOND
;
411 /* Send command to session daemon */
412 ret
= send_session_msg(lsm
);
414 /* Ret value is a valid lttng error code. */
417 /* Send var len data */
418 ret
= send_session_varlen(vardata
, varlen
);
420 /* Ret value is a valid lttng error code. */
424 /* Get header from data transmission */
425 ret
= recv_data_sessiond(&llm
, sizeof(llm
));
427 /* Ret value is a valid lttng error code. */
431 /* Check error code if OK */
432 if (llm
.ret_code
!= LTTNG_OK
) {
437 size
= llm
.data_size
;
439 /* If client free with size 0 */
447 data
= (void*) malloc(size
);
449 /* Get payload data */
450 ret
= recv_data_sessiond(data
, size
);
457 * Extra protection not to dereference a NULL pointer. If buf is NULL at
458 * this point, an error is returned and data is freed.
461 ret
= -LTTNG_ERR_INVALID
;
470 disconnect_sessiond();
475 * Create lttng handle and return pointer.
476 * The returned pointer will be NULL in case of malloc() error.
478 struct lttng_handle
*lttng_create_handle(const char *session_name
,
479 struct lttng_domain
*domain
)
481 struct lttng_handle
*handle
= NULL
;
483 if (domain
== NULL
) {
487 handle
= malloc(sizeof(struct lttng_handle
));
488 if (handle
== NULL
) {
489 PERROR("malloc handle");
493 /* Copy session name */
494 lttng_ctl_copy_string(handle
->session_name
, session_name
,
495 sizeof(handle
->session_name
));
497 /* Copy lttng domain */
498 lttng_ctl_copy_lttng_domain(&handle
->domain
, domain
);
505 * Destroy handle by free(3) the pointer.
507 void lttng_destroy_handle(struct lttng_handle
*handle
)
513 * Register an outside consumer.
514 * Returns size of returned session payload data or a negative error code.
516 int lttng_register_consumer(struct lttng_handle
*handle
,
517 const char *socket_path
)
519 struct lttcomm_session_msg lsm
;
521 if (handle
== NULL
|| socket_path
== NULL
) {
522 return -LTTNG_ERR_INVALID
;
525 memset(&lsm
, 0, sizeof(lsm
));
526 lsm
.cmd_type
= LTTNG_REGISTER_CONSUMER
;
527 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
528 sizeof(lsm
.session
.name
));
529 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
531 lttng_ctl_copy_string(lsm
.u
.reg
.path
, socket_path
, sizeof(lsm
.u
.reg
.path
));
533 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
537 * Start tracing for all traces of the session.
538 * Returns size of returned session payload data or a negative error code.
540 int lttng_start_tracing(const char *session_name
)
542 struct lttcomm_session_msg lsm
;
544 if (session_name
== NULL
) {
545 return -LTTNG_ERR_INVALID
;
548 memset(&lsm
, 0, sizeof(lsm
));
549 lsm
.cmd_type
= LTTNG_START_TRACE
;
551 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
552 sizeof(lsm
.session
.name
));
554 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
558 * Stop tracing for all traces of the session.
560 static int _lttng_stop_tracing(const char *session_name
, int wait
)
563 struct lttcomm_session_msg lsm
;
565 if (session_name
== NULL
) {
566 return -LTTNG_ERR_INVALID
;
569 memset(&lsm
, 0, sizeof(lsm
));
570 lsm
.cmd_type
= LTTNG_STOP_TRACE
;
572 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
573 sizeof(lsm
.session
.name
));
575 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
576 if (ret
< 0 && ret
!= -LTTNG_ERR_TRACE_ALREADY_STOPPED
) {
584 /* Check for data availability */
586 data_ret
= lttng_data_pending(session_name
);
588 /* Return the data available call error. */
594 * Data sleep time before retrying (in usec). Don't sleep if the call
595 * returned value indicates availability.
598 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME
);
600 } while (data_ret
!= 0);
608 * Stop tracing and wait for data availability.
610 int lttng_stop_tracing(const char *session_name
)
612 return _lttng_stop_tracing(session_name
, 1);
616 * Stop tracing but _don't_ wait for data availability.
618 int lttng_stop_tracing_no_wait(const char *session_name
)
620 return _lttng_stop_tracing(session_name
, 0);
624 * Add context to a channel.
626 * If the given channel is NULL, add the contexts to all channels.
627 * The event_name param is ignored.
629 * Returns the size of the returned payload data or a negative error code.
631 int lttng_add_context(struct lttng_handle
*handle
,
632 struct lttng_event_context
*ctx
, const char *event_name
,
633 const char *channel_name
)
635 struct lttcomm_session_msg lsm
;
637 /* Safety check. Both are mandatory */
638 if (handle
== NULL
|| ctx
== NULL
) {
639 return -LTTNG_ERR_INVALID
;
642 memset(&lsm
, 0, sizeof(lsm
));
644 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
646 /* If no channel name, send empty string. */
647 if (channel_name
== NULL
) {
648 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, "",
649 sizeof(lsm
.u
.context
.channel_name
));
651 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, channel_name
,
652 sizeof(lsm
.u
.context
.channel_name
));
655 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
657 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
659 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
660 sizeof(lsm
.session
.name
));
662 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
666 * Enable event(s) for a channel.
667 * If no event name is specified, all events are enabled.
668 * If no channel name is specified, the default 'channel0' is used.
669 * Returns size of returned session payload data or a negative error code.
671 int lttng_enable_event(struct lttng_handle
*handle
,
672 struct lttng_event
*ev
, const char *channel_name
)
674 return lttng_enable_event_with_exclusions(handle
, ev
, channel_name
,
679 * Create or enable an event with a filter expression.
681 * Return negative error value on error.
682 * Return size of returned session payload data if OK.
684 int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
685 struct lttng_event
*event
, const char *channel_name
,
686 const char *filter_expression
)
688 return lttng_enable_event_with_exclusions(handle
, event
, channel_name
,
689 filter_expression
, 0, NULL
);
693 * Depending on the event, return a newly allocated JUL filter expression or
694 * NULL if not applicable.
696 * An event with NO loglevel and the name is * will return NULL.
698 static char *set_jul_filter(const char *filter
, struct lttng_event
*ev
)
701 char *jul_filter
= NULL
;
705 /* Don't add filter for the '*' event. */
706 if (ev
->name
[0] != '*') {
708 err
= asprintf(&jul_filter
, "(%s) && (logger_name == \"%s\")", filter
,
711 err
= asprintf(&jul_filter
, "logger_name == \"%s\"", ev
->name
);
719 /* Add loglevel filtering if any for the JUL domain. */
720 if (ev
->loglevel_type
!= LTTNG_EVENT_LOGLEVEL_ALL
) {
723 if (ev
->loglevel_type
== LTTNG_EVENT_LOGLEVEL_RANGE
) {
729 if (filter
|| jul_filter
) {
732 err
= asprintf(&new_filter
, "(%s) && (int_loglevel %s %d)",
733 jul_filter
? jul_filter
: filter
, op
,
738 jul_filter
= new_filter
;
740 err
= asprintf(&jul_filter
, "int_loglevel %s %d", op
,
756 * Generate the filter bytecode from a give filter expression string. Put the
757 * newly allocated parser context in ctxp and populate the lsm object with the
760 * Return 0 on success else a LTTNG_ERR_* code and ctxp is untouched.
762 static int generate_filter(char *filter_expression
,
763 struct lttcomm_session_msg
*lsm
, struct filter_parser_ctx
**ctxp
)
766 struct filter_parser_ctx
*ctx
= NULL
;
769 assert(filter_expression
);
774 * Casting const to non-const, as the underlying function will use it in
777 fmem
= lttng_fmemopen((void *) filter_expression
,
778 strlen(filter_expression
), "r");
780 fprintf(stderr
, "Error opening memory as stream\n");
781 ret
= -LTTNG_ERR_FILTER_NOMEM
;
784 ctx
= filter_parser_ctx_alloc(fmem
);
786 fprintf(stderr
, "Error allocating parser\n");
787 ret
= -LTTNG_ERR_FILTER_NOMEM
;
788 goto filter_alloc_error
;
790 ret
= filter_parser_ctx_append_ast(ctx
);
792 fprintf(stderr
, "Parse error\n");
793 ret
= -LTTNG_ERR_FILTER_INVAL
;
796 ret
= filter_visitor_set_parent(ctx
);
798 fprintf(stderr
, "Set parent error\n");
799 ret
= -LTTNG_ERR_FILTER_INVAL
;
803 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
806 fprintf(stderr
, "XML print error\n");
807 ret
= -LTTNG_ERR_FILTER_INVAL
;
812 dbg_printf("Generating IR... ");
814 ret
= filter_visitor_ir_generate(ctx
);
816 fprintf(stderr
, "Generate IR error\n");
817 ret
= -LTTNG_ERR_FILTER_INVAL
;
820 dbg_printf("done\n");
822 dbg_printf("Validating IR... ");
824 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
826 ret
= -LTTNG_ERR_FILTER_INVAL
;
829 /* Validate strings used as literals in the expression */
830 ret
= filter_visitor_ir_validate_string(ctx
);
832 ret
= -LTTNG_ERR_FILTER_INVAL
;
835 dbg_printf("done\n");
837 dbg_printf("Generating bytecode... ");
839 ret
= filter_visitor_bytecode_generate(ctx
);
841 fprintf(stderr
, "Generate bytecode error\n");
842 ret
= -LTTNG_ERR_FILTER_INVAL
;
845 dbg_printf("done\n");
846 dbg_printf("Size of bytecode generated: %u bytes.\n",
847 bytecode_get_len(&ctx
->bytecode
->b
));
849 lsm
->u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
850 + bytecode_get_len(&ctx
->bytecode
->b
);
851 lsm
->u
.enable
.expression_len
= strlen(filter_expression
) + 1;
853 /* No need to keep the memory stream. */
854 if (fclose(fmem
) != 0) {
863 filter_parser_ctx_free(ctx
);
865 if (fclose(fmem
) != 0) {
873 * Enable event(s) for a channel, possibly with exclusions and a filter.
874 * If no event name is specified, all events are enabled.
875 * If no channel name is specified, the default name is used.
876 * If filter expression is not NULL, the filter is set for the event.
877 * If exclusion count is not zero, the exclusions are set for the event.
878 * Returns size of returned session payload data or a negative error code.
880 int lttng_enable_event_with_exclusions(struct lttng_handle
*handle
,
881 struct lttng_event
*ev
, const char *channel_name
,
882 const char *original_filter_expression
,
883 int exclusion_count
, char **exclusion_list
)
885 struct lttcomm_session_msg lsm
;
888 unsigned int free_filter_expression
= 0;
889 struct filter_parser_ctx
*ctx
= NULL
;
891 * Cast as non-const since we may replace the filter expression
892 * by a dynamically allocated string. Otherwise, the original
893 * string is not modified.
895 char *filter_expression
= (char *) original_filter_expression
;
897 if (handle
== NULL
|| ev
== NULL
) {
898 ret
= -LTTNG_ERR_INVALID
;
902 /* Empty filter string will always be rejected by the parser
903 * anyway, so treat this corner-case early to eliminate
904 * lttng_fmemopen error for 0-byte allocation.
906 if (filter_expression
&& filter_expression
[0] == '\0') {
907 ret
= -LTTNG_ERR_INVALID
;
911 memset(&lsm
, 0, sizeof(lsm
));
913 /* If no channel name, send empty string. */
914 if (channel_name
== NULL
) {
915 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, "",
916 sizeof(lsm
.u
.enable
.channel_name
));
918 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
919 sizeof(lsm
.u
.enable
.channel_name
));
922 if (ev
->name
[0] != '\0') {
923 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
925 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
928 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
929 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
931 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
932 sizeof(lsm
.session
.name
));
933 lsm
.u
.enable
.exclusion_count
= exclusion_count
;
934 lsm
.u
.enable
.bytecode_len
= 0;
937 * For the JUL domain, a filter is enforced except for the enable all
938 * event. This is done to avoid having the event in all sessions thus
939 * filtering by logger name.
941 if (exclusion_count
== 0 && filter_expression
== NULL
&&
942 (handle
->domain
.type
!= LTTNG_DOMAIN_JUL
&&
943 handle
->domain
.type
!= LTTNG_DOMAIN_LOG4J
)) {
948 * We have either a filter or some exclusions, so we need to set up
949 * a variable-length memory block from where to send the data
952 /* Parse filter expression */
953 if (filter_expression
!= NULL
|| handle
->domain
.type
== LTTNG_DOMAIN_JUL
954 || handle
->domain
.type
== LTTNG_DOMAIN_LOG4J
) {
955 if (handle
->domain
.type
== LTTNG_DOMAIN_JUL
||
956 handle
->domain
.type
== LTTNG_DOMAIN_LOG4J
) {
959 /* Setup JUL filter if needed. */
960 jul_filter
= set_jul_filter(filter_expression
, ev
);
962 if (!filter_expression
) {
963 /* No JUL and no filter, just skip everything below. */
968 * With a JUL filter, the original filter has been added to it
969 * thus replace the filter expression.
971 filter_expression
= jul_filter
;
972 free_filter_expression
= 1;
976 ret
= generate_filter(filter_expression
, &lsm
, &ctx
);
982 varlen_data
= zmalloc(lsm
.u
.enable
.bytecode_len
983 + lsm
.u
.enable
.expression_len
984 + LTTNG_SYMBOL_NAME_LEN
* exclusion_count
);
986 ret
= -LTTNG_ERR_EXCLUSION_NOMEM
;
990 /* Put exclusion names first in the data */
991 while (exclusion_count
--) {
992 strncpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* exclusion_count
,
993 *(exclusion_list
+ exclusion_count
), LTTNG_SYMBOL_NAME_LEN
);
995 /* Add filter expression next */
996 if (lsm
.u
.enable
.expression_len
!= 0) {
998 + LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
,
1000 lsm
.u
.enable
.expression_len
);
1002 /* Add filter bytecode next */
1003 if (ctx
&& lsm
.u
.enable
.bytecode_len
!= 0) {
1005 + LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
1006 + lsm
.u
.enable
.expression_len
,
1008 lsm
.u
.enable
.bytecode_len
);
1011 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, varlen_data
,
1012 (LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
) +
1013 lsm
.u
.enable
.bytecode_len
+ lsm
.u
.enable
.expression_len
, NULL
);
1017 if (filter_expression
&& ctx
) {
1018 filter_bytecode_free(ctx
);
1019 filter_ir_free(ctx
);
1020 filter_parser_ctx_free(ctx
);
1023 if (free_filter_expression
) {
1025 * The filter expression has been replaced and must be freed as it is
1026 * not the original filter expression received as a parameter.
1028 free(filter_expression
);
1032 * Return directly to the caller and don't ask the sessiond since something
1033 * went wrong in the parsing of data above.
1038 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1043 * Disable event(s) of a channel and domain.
1044 * If no event name is specified, all events are disabled.
1045 * If no channel name is specified, the default 'channel0' is used.
1046 * Returns size of returned session payload data or a negative error code.
1048 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
1049 const char *channel_name
)
1051 struct lttcomm_session_msg lsm
;
1053 if (handle
== NULL
) {
1054 return -LTTNG_ERR_INVALID
;
1057 memset(&lsm
, 0, sizeof(lsm
));
1059 /* If no channel name, send empty string. */
1060 if (channel_name
== NULL
) {
1061 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, "",
1062 sizeof(lsm
.u
.disable
.channel_name
));
1064 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
1065 sizeof(lsm
.u
.disable
.channel_name
));
1068 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1071 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
1072 sizeof(lsm
.u
.disable
.name
));
1073 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
1075 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
1078 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1079 sizeof(lsm
.session
.name
));
1081 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1085 * Enable channel per domain
1086 * Returns size of returned session payload data or a negative error code.
1088 int lttng_enable_channel(struct lttng_handle
*handle
,
1089 struct lttng_channel
*chan
)
1091 struct lttcomm_session_msg lsm
;
1094 * NULL arguments are forbidden. No default values.
1096 if (handle
== NULL
|| chan
== NULL
) {
1097 return -LTTNG_ERR_INVALID
;
1100 memset(&lsm
, 0, sizeof(lsm
));
1102 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
1104 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
1106 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1108 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1109 sizeof(lsm
.session
.name
));
1111 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1115 * All tracing will be stopped for registered events of the channel.
1116 * Returns size of returned session payload data or a negative error code.
1118 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
1120 struct lttcomm_session_msg lsm
;
1122 /* Safety check. Both are mandatory */
1123 if (handle
== NULL
|| name
== NULL
) {
1124 return -LTTNG_ERR_INVALID
;
1127 memset(&lsm
, 0, sizeof(lsm
));
1129 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
1131 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
1132 sizeof(lsm
.u
.disable
.channel_name
));
1134 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1136 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1137 sizeof(lsm
.session
.name
));
1139 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1143 * Lists all available tracepoints of domain.
1144 * Sets the contents of the events array.
1145 * Returns the number of lttng_event entries in events;
1146 * on error, returns a negative value.
1148 int lttng_list_tracepoints(struct lttng_handle
*handle
,
1149 struct lttng_event
**events
)
1152 struct lttcomm_session_msg lsm
;
1154 if (handle
== NULL
) {
1155 return -LTTNG_ERR_INVALID
;
1158 memset(&lsm
, 0, sizeof(lsm
));
1159 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1160 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1162 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
1167 return ret
/ sizeof(struct lttng_event
);
1171 * Lists all available tracepoint fields of domain.
1172 * Sets the contents of the event field array.
1173 * Returns the number of lttng_event_field entries in events;
1174 * on error, returns a negative value.
1176 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1177 struct lttng_event_field
**fields
)
1180 struct lttcomm_session_msg lsm
;
1182 if (handle
== NULL
) {
1183 return -LTTNG_ERR_INVALID
;
1186 memset(&lsm
, 0, sizeof(lsm
));
1187 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1188 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1190 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
1195 return ret
/ sizeof(struct lttng_event_field
);
1199 * Returns a human readable string describing
1200 * the error code (a negative value).
1202 const char *lttng_strerror(int code
)
1204 return error_get_str(code
);
1208 * Create a brand new session using name and url for destination.
1210 * Returns LTTNG_OK on success or a negative error code.
1212 int lttng_create_session(const char *name
, const char *url
)
1216 struct lttcomm_session_msg lsm
;
1217 struct lttng_uri
*uris
= NULL
;
1220 return -LTTNG_ERR_INVALID
;
1223 memset(&lsm
, 0, sizeof(lsm
));
1225 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1226 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1228 /* There should never be a data URL */
1229 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1231 return -LTTNG_ERR_INVALID
;
1234 lsm
.u
.uri
.size
= size
;
1236 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1237 sizeof(struct lttng_uri
) * size
, NULL
);
1244 * Destroy session using name.
1245 * Returns size of returned session payload data or a negative error code.
1247 int lttng_destroy_session(const char *session_name
)
1249 struct lttcomm_session_msg lsm
;
1251 if (session_name
== NULL
) {
1252 return -LTTNG_ERR_INVALID
;
1255 memset(&lsm
, 0, sizeof(lsm
));
1256 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1258 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1259 sizeof(lsm
.session
.name
));
1261 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1265 * Ask the session daemon for all available sessions.
1266 * Sets the contents of the sessions array.
1267 * Returns the number of lttng_session entries in sessions;
1268 * on error, returns a negative value.
1270 int lttng_list_sessions(struct lttng_session
**sessions
)
1273 struct lttcomm_session_msg lsm
;
1275 memset(&lsm
, 0, sizeof(lsm
));
1276 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1277 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1282 return ret
/ sizeof(struct lttng_session
);
1286 * Ask the session daemon for all available domains of a session.
1287 * Sets the contents of the domains array.
1288 * Returns the number of lttng_domain entries in domains;
1289 * on error, returns a negative value.
1291 int lttng_list_domains(const char *session_name
,
1292 struct lttng_domain
**domains
)
1295 struct lttcomm_session_msg lsm
;
1297 if (session_name
== NULL
) {
1298 return -LTTNG_ERR_INVALID
;
1301 memset(&lsm
, 0, sizeof(lsm
));
1302 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1304 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1305 sizeof(lsm
.session
.name
));
1307 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1312 return ret
/ sizeof(struct lttng_domain
);
1316 * Ask the session daemon for all available channels of a session.
1317 * Sets the contents of the channels array.
1318 * Returns the number of lttng_channel entries in channels;
1319 * on error, returns a negative value.
1321 int lttng_list_channels(struct lttng_handle
*handle
,
1322 struct lttng_channel
**channels
)
1325 struct lttcomm_session_msg lsm
;
1327 if (handle
== NULL
) {
1328 return -LTTNG_ERR_INVALID
;
1331 memset(&lsm
, 0, sizeof(lsm
));
1332 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1333 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1334 sizeof(lsm
.session
.name
));
1336 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1338 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1343 return ret
/ sizeof(struct lttng_channel
);
1347 * Ask the session daemon for all available events of a session channel.
1348 * Sets the contents of the events array.
1349 * Returns the number of lttng_event entries in events;
1350 * on error, returns a negative value.
1352 int lttng_list_events(struct lttng_handle
*handle
,
1353 const char *channel_name
, struct lttng_event
**events
)
1356 struct lttcomm_session_msg lsm
;
1358 /* Safety check. An handle and channel name are mandatory */
1359 if (handle
== NULL
|| channel_name
== NULL
) {
1360 return -LTTNG_ERR_INVALID
;
1363 memset(&lsm
, 0, sizeof(lsm
));
1364 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1365 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1366 sizeof(lsm
.session
.name
));
1367 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1368 sizeof(lsm
.u
.list
.channel_name
));
1370 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1372 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1377 return ret
/ sizeof(struct lttng_event
);
1381 * Sets the tracing_group variable with name.
1382 * This function allocates memory pointed to by tracing_group.
1383 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1385 int lttng_set_tracing_group(const char *name
)
1388 return -LTTNG_ERR_INVALID
;
1391 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1392 return -LTTNG_ERR_FATAL
;
1399 * Returns size of returned session payload data or a negative error code.
1401 int lttng_calibrate(struct lttng_handle
*handle
,
1402 struct lttng_calibrate
*calibrate
)
1404 struct lttcomm_session_msg lsm
;
1406 /* Safety check. NULL pointer are forbidden */
1407 if (handle
== NULL
|| calibrate
== NULL
) {
1408 return -LTTNG_ERR_INVALID
;
1411 memset(&lsm
, 0, sizeof(lsm
));
1412 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1413 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1415 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1417 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1421 * Set default channel attributes.
1422 * If either or both of the arguments are null, attr content is zeroe'd.
1424 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1425 struct lttng_channel_attr
*attr
)
1428 if (attr
== NULL
|| domain
== NULL
) {
1432 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1434 /* Same for all domains. */
1435 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1436 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1437 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1439 switch (domain
->type
) {
1440 case LTTNG_DOMAIN_KERNEL
:
1441 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1442 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1443 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1444 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1445 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1447 case LTTNG_DOMAIN_UST
:
1448 switch (domain
->buf_type
) {
1449 case LTTNG_BUFFER_PER_UID
:
1450 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1451 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1452 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1453 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1454 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1456 case LTTNG_BUFFER_PER_PID
:
1458 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1459 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1460 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1461 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1462 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1466 /* Default behavior: leave set to 0. */
1472 * Check if session daemon is alive.
1474 * Return 1 if alive or 0 if not.
1475 * On error returns a negative value.
1477 int lttng_session_daemon_alive(void)
1481 ret
= set_session_daemon_path();
1487 if (*sessiond_sock_path
== '\0') {
1489 * No socket path set. Weird error which means the constructor was not
1495 ret
= try_connect_sessiond(sessiond_sock_path
);
1506 * Set URL for a consumer for a session and domain.
1508 * Return 0 on success, else a negative value.
1510 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1511 const char *control_url
, const char *data_url
)
1515 struct lttcomm_session_msg lsm
;
1516 struct lttng_uri
*uris
= NULL
;
1518 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1519 return -LTTNG_ERR_INVALID
;
1522 memset(&lsm
, 0, sizeof(lsm
));
1524 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1526 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1527 sizeof(lsm
.session
.name
));
1528 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1530 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1532 return -LTTNG_ERR_INVALID
;
1535 lsm
.u
.uri
.size
= size
;
1537 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1538 sizeof(struct lttng_uri
) * size
, NULL
);
1547 int lttng_enable_consumer(struct lttng_handle
*handle
)
1555 int lttng_disable_consumer(struct lttng_handle
*handle
)
1561 * This is an extension of create session that is ONLY and SHOULD only be used
1562 * by the lttng command line program. It exists to avoid using URI parsing in
1565 * We need the date and time for the trace path subdirectory for the case where
1566 * the user does NOT define one using either -o or -U. Using the normal
1567 * lttng_create_session API call, we have no clue on the session daemon side if
1568 * the URL was generated automatically by the client or define by the user.
1570 * So this function "wrapper" is hidden from the public API, takes the datetime
1571 * string and appends it if necessary to the URI subdirectory before sending it
1572 * to the session daemon.
1574 * With this extra function, the lttng_create_session call behavior is not
1575 * changed and the timestamp is appended to the URI on the session daemon side
1578 int _lttng_create_session_ext(const char *name
, const char *url
,
1579 const char *datetime
)
1583 struct lttcomm_session_msg lsm
;
1584 struct lttng_uri
*uris
= NULL
;
1586 if (name
== NULL
|| datetime
== NULL
) {
1587 return -LTTNG_ERR_INVALID
;
1590 memset(&lsm
, 0, sizeof(lsm
));
1592 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1593 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1595 /* There should never be a data URL */
1596 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1598 ret
= -LTTNG_ERR_INVALID
;
1602 lsm
.u
.uri
.size
= size
;
1604 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1605 /* Don't append datetime if the name was automatically created. */
1606 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1607 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1608 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1611 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1614 PERROR("snprintf uri subdir");
1615 ret
= -LTTNG_ERR_FATAL
;
1620 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1621 sizeof(struct lttng_uri
) * size
, NULL
);
1629 * For a given session name, this call checks if the data is ready to be read
1630 * or is still being extracted by the consumer(s) hence not ready to be used by
1633 int lttng_data_pending(const char *session_name
)
1636 struct lttcomm_session_msg lsm
;
1638 if (session_name
== NULL
) {
1639 return -LTTNG_ERR_INVALID
;
1642 memset(&lsm
, 0, sizeof(lsm
));
1643 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1645 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1646 sizeof(lsm
.session
.name
));
1648 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1651 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1652 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1653 * that the data is available. Yes it is hackish but for now this is the
1664 * Create a session exclusively used for snapshot.
1666 * Returns LTTNG_OK on success or a negative error code.
1668 int lttng_create_session_snapshot(const char *name
, const char *snapshot_url
)
1672 struct lttcomm_session_msg lsm
;
1673 struct lttng_uri
*uris
= NULL
;
1676 return -LTTNG_ERR_INVALID
;
1679 memset(&lsm
, 0, sizeof(lsm
));
1681 lsm
.cmd_type
= LTTNG_CREATE_SESSION_SNAPSHOT
;
1682 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1684 size
= uri_parse_str_urls(snapshot_url
, NULL
, &uris
);
1686 return -LTTNG_ERR_INVALID
;
1689 lsm
.u
.uri
.size
= size
;
1691 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1692 sizeof(struct lttng_uri
) * size
, NULL
);
1699 * Create a session exclusively used for live.
1701 * Returns LTTNG_OK on success or a negative error code.
1703 int lttng_create_session_live(const char *name
, const char *url
,
1704 unsigned int timer_interval
)
1708 struct lttcomm_session_msg lsm
;
1709 struct lttng_uri
*uris
= NULL
;
1712 return -LTTNG_ERR_INVALID
;
1715 memset(&lsm
, 0, sizeof(lsm
));
1717 lsm
.cmd_type
= LTTNG_CREATE_SESSION_LIVE
;
1718 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1721 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1723 ret
= -LTTNG_ERR_INVALID
;
1727 /* file:// is not accepted for live session. */
1728 if (uris
[0].dtype
== LTTNG_DST_PATH
) {
1729 ret
= -LTTNG_ERR_INVALID
;
1736 lsm
.u
.session_live
.nb_uri
= size
;
1737 lsm
.u
.session_live
.timer_interval
= timer_interval
;
1739 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1740 sizeof(struct lttng_uri
) * size
, NULL
);
1750 static void __attribute__((constructor
)) init()
1752 /* Set default session group */
1753 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1759 static void __attribute__((destructor
)) lttng_ctl_exit()
1761 free(tracing_group
);